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Bern, Switzerland

The University of Bern is a university in the Swiss capital of Bern and was founded in 1834. It is regulated and financed by the Canton of Bern. It is a comprehensive university offering a broad choice of courses and programmes in eight faculties and some 160 institutes. With around 15,000 students, the University of Bern is a medium-sized Swiss university. Wikipedia.


Fotopoulos A.,University of Turin | Prezas N.,University of Bern
Nuclear Physics B | Year: 2011

We derive pomeron vertex operators for bosonic strings and superstrings in the presence of D-branes. We demonstrate how they can be used in order to compute the Regge behavior of string amplitudes on D-branes and the amplitude of ultrarelativistic D-brane scattering. After a lightning review of the BCFW method, we proceed in a classification of the various BCFW shifts possible in a field/string theory in the presence of defects/D-branes. The BCFW shifts present several novel features, such as the possibility of performing single particle momentum shifts, due to the breaking of momentum conservation in the directions normal to the defect. Using the pomeron vertices we show that superstring amplitudes on the disc involving both open and closed strings should obey BCFW recursion relations. As a particular example, we analyze explicitly the case of 1?1 scattering of level one closed string states off a D-brane. Finally, we investigate whether the eikonal Regge regime conjecture holds in the presence of D-branes. © 2011 Elsevier B.V. Source


Gaggiotti O.E.,CNRS Alpine Ecology Laboratory | Foll M.,University of Bern
Molecular Ecology Resources | Year: 2010

We review a model-based approach to estimate local population FST's that is based on the multinomial-Dirichlet distribution, the so-called F-model. As opposed to the standard method of estimating a single FST value, this approach takes into account the fact that in most if not all realistic situations, local populations differ in their effective sizes and migration rates. Therefore, the use of this approach can help better describe the genetic structure of populations. Despite this obvious advantage, this method has remained largely underutilized by molecular ecologists. Thus, the objective of this review is to foster its use for studying the genetic structure of metapopulations. We present the derivation of the Bayesian formulation for the estimation of population-specific FST's based on the multinomial-Dirichlet distribution. We describe several recent applications of the F-model and present the results of a small simulation study that explains how the F-model can help better describe the genetic structure of populations. © 2010 Blackwell Publishing Ltd. Source


Ptak R.,University of Geneva | Muri R.M.,University of Bern
Frontiers in Human Neuroscience | Year: 2013

The parietal cortex is a critical interface for attention and integration of multiple sensory signals that can be used for the implementation of motor plans. Many neurons in this region exhibit strong attention-, reach-, graspor saccade-related activity. Here, we review human lesion studies supporting the critical role of the parietal cortex in saccade planning. Studies of patients with unilateral parietal damage and spatial neglect reveal characteristic spatially lateralized deficits of saccade programming when multiple stimuli compete for attention. However, these patients also show bilateral impairments of saccade initiation and control that are difficult to explain in the context of their lateralized deficits of visual attention. These findings are reminiscent of the deficits of oculomotor control observed in patients with Bálint's syndrome consecutive to bilateral parietal damage. We propose that some oculomotor deficits following parietal damage are compatible with a decisive role of the parietal cortex in saccade planning under conditions of sensory competition, while other deficits reflect disinhibition of low-level structures of the oculomotor network in the absence of top-down parietal modulation. © 2013 Ptak and Müri. Source


Fotiadis D.,University of Bern
Methods in molecular biology (Clifton, N.J.) | Year: 2013

In this chapter the methodological bases are provided to achieve subnanometer resolution on two-dimensional (2D) membrane protein crystals by atomic force microscopy (AFM). This is outlined in detail with the example of AFM studies of the outer membrane protein F (OmpF) from the bacterium Escherichia coli (E. coli). We describe in detail the high-resolution imaging of 2D OmpF crystals in aqueous solution and under near-physiological conditions. The topographs of OmpF, and stylus effects and artifacts encountered when imaging by AFM are discussed. Source


Leunig M.,Orthopaedic Surg. Schulthess Clinic | Ganz R.,University of Bern
Bone and Joint Journal | Year: 2014

The use of joint-preserving surgery of the hip has been largely abandoned since the introduction of total hip replacement. However, with the modification of such techniques as pelvic osteotomy, and the introduction of intracapsular procedures such as surgical hip dislocation and arthroscopy, previously unexpected options for the surgical treatment of sequelae of childhood conditions, including developmental dysplasia of the hip, slipped upper femoral epiphysis and Perthes' disease, have become available. Moreover, femoroacetabular impingement has been identified as a significant aetiological factor in the development of osteoarthritis in many hips previously considered to suffer from primary osteoarthritis. As mechanical causes of degenerative joint disease are now recognised earlier in the disease process, these techniques may be used to decelerate or even prevent progression to osteoarthritis. We review the recent development of these concepts and the associated surgical techniques. © 2014 The British Editorial Society of Bone & Joint Surgery. Source


Knutti R.,ETH Zurich | Plattner G.-K.,University of Bern
Journal of Climate | Year: 2012

In a recent paper, Schwartz et al. suggest that 1) over the last century the earth haswarmed less than expected, and they discuss several factors that could explain the discrepancy, including climate sensitivity estimates and aerosol forcing. Schwartz et al. then continue to 2) estimate the allowed carbon emissions for stabilization of global temperature, and find that given the uncertainty in the climate sensitivity even the sign of these allowed carbon emissions is unknown, implying that past emissions may already have committed the earth to 2°C warming for a best-estimate value of climate sensitivity of 3 K. Both of these conclusions in the Schwartz et al. study are revisited herein, and it is shown that 1) in contrast to Schwartz et al., current assessments of climate sensitivity, radiative forcing, and thermal disequilibrium do not support the claim of a discrepancy between expected and observed warming; and 2) the allowed emissions estimated by Schwartz et al. are in conflict with results from a hierarchy of climate-carbon cycle models and are strongly underestimated due to erroneous assumptions about the behavior of the carbon cycle and a confusion of the relevant time scales. © 2012 American Meteorological Society. Source


Drugs may stimulate the immune system by forming hapten-carrier complexes or via their pharmacological features, namely by noncovalent binding to proteins such as immune receptors. The latter type of immune stimulation is called the p-i concept, meaning pharmacological interaction with immune receptors, which implies stimulation of the immune system by noncovalent binding of a drug to T-cell receptors for antigens (p-i TCR) or human leukocyte antigens (p-i HLA). The functional consequences of these interactions are heterogeneous: clinically, it can lead to T-cell mediated reactions such as Stevens-Johnson syndrome/toxic epidermal necrolysis, drug rash with eosinophilia and systemic symptoms, acute generalized exanthematous pustulosis, and maculopapular eruptions. If the drug binds to the TCR, it can become stimulatory, and an additional interaction with HLA/peptide complexes is necessary for full stimulation. The T-cell reaction can be oligoclonal or polyclonal. Binding of drugs to an HLA molecule can have two consequences: if the drug can modify the HLA molecule, a distinct repertoire of peptides might be presented: this is the altered peptide model. However, peptide exchange is not necessary to make the peptide-HLA complex immunogenic: if the drug binds to HLA, already the complex of altered HLA and normal peptide is immunogenic and able to stimulate T-cells (altered peptide-HLA model). The immunological and clinical consequences of different forms of the p-i concept are described with typical p-i binding drugs such as abacavir, carbamazepine, flucloxacillin, allopurinol, and sulfamethoxazole. Thereby the role of drug binding to HLA or TCR, the affinity of drug binding, additional TCR binding, and potential oligoclonality are described and compared. © 2013, Taiwanese Dermatological Association. Published by Elsevier Taiwan LLC. All rights reserved. Source


Martinez-Garcia A.,ETH Zurich | Sigman D.M.,Princeton University | Ren H.,Academia Sinica, Taiwan | Anderson R.F.,Lamont Doherty Earth Observatory | And 5 more authors.
Science | Year: 2014

John H. Martin, who discovered widespread iron limitation of ocean productivity, proposed that dust-borne iron fertilization of Southern Ocean phytoplankton caused the ice age reduction in atmospheric carbon dioxide (CO2). In a sediment core from the Subantarctic Atlantic, we measured foraminifera-bound nitrogen isotopes to reconstruct ice age nitrate consumption, burial fluxes of iron, and proxies for productivity. Peak glacial times and millennial cold events are characterized by increases in dust flux, productivity, and the degree of nitrate consumption; this combination is uniquely consistent with Subantarctic iron fertilization. The associated strengthening of the Southern Ocean's biological pump can explain the lowering of CO2 at the transition from mid-climate states to full ice age conditions as well as the millennial-scale CO2 oscillations. Source


Levayer R.,Aix - Marseille University | Levayer R.,University of Bern | Lecuit T.,Aix - Marseille University
Developmental Cell | Year: 2013

Actomyosin flows are involved in a variety of cellular processes, including cytokinesis, cell migration, polarization, and morphogenesis. In epithelia, flow polarization orients cell deformations. It is unclear, however, how flows are polarized and how global patterns of junction remodeling emerge from flow polarization locally. We address this question during intercalation-driving extension of the Drosophila germband. Intercalation is associated with polarized junction remodeling, whereby actomyosin pulses flow anisotropically toward dorsal-ventral junctions and shrink them. Here, we show that planar polarization of flows emerges from polarized fluctuations in the levels of E-cadherin clusters that produce transient and oscillating asymmetries of coupling. These fluctuations are triggered by polarized E-cadherin endocytosis and are amplified by flow itself. This work suggests that fluctuations and mechanical instability are not the consequences of limited control over the systems key parameters, but rather that they define the axis of symmetry breaking. © 2013 Elsevier Inc. Source


Laine M.,University of Bern
European Physical Journal C | Year: 2012

It has been argued by Caron-Huot that infrared contributions to the jet quenching parameter in hot QCD, denoted by q, can be extracted from an analysis of a certain static-potential related observable within the dimensionally reduced effective field theory. Following this philosophy, the order of magnitude of a non-perturbative contribution to q from the colour-magnetic scale, g2T/π, is estimated. The result is small; it is probably below the parametrically perturbative but in practice slowly convergent contributions from the colour-electric scale, whose all-orders resummation therefore remains an important challenge. © 2012 The Author(s). Source


Lithgow T.,Monash University | Schneider A.,University of Bern
Philosophical Transactions of the Royal Society B: Biological Sciences | Year: 2010

All eukaryotes require mitochondria for survival and growth. The origin of mitochondria can be traced down to a single endosymbiotic event between two probably prokaryotic organisms. Subsequent evolution has left mitochondria a collection of heterogeneous organelle variants. Most of these variants have retained their own genome and translation system. In hydrogenosomes and mitosomes, however, the entire genome was lost. All types of mitochondria import most of their proteome from the cytosol, irrespective of whether they have a genome or not. Moreover, in most eukaryotes, a variable number of tRNAs that are required for mitochondrial translation are also imported. Thus, import of macromolecules, both proteins and tRNA, is essential for mitochondrial biogenesis. Here, we review what is known about the evolutionary history of the two processes using a recently revised eukaryotic phylogeny as a framework. We discuss how the processes of protein import and tRNA import relate to each other in an evolutionary context. © 2010 The Royal Society. Source


This article discusses the connection between crystallography and material science. It sheds light on some of the research opportunities that are currently available and it critically reviews the directions taken by the scientific community in the field of crystal engineering. The focus is on materials formed by the assembly of organic and organometallic molecular building blocks. © Schweizerische Chemische Gesellschaft. Source


This article seeks to extend the scope of existing literature on migration in Kyrgyzstan by revealing the material and moral assessment of labour migration and remittances amongst the people of Sopu Korgon, a village in Southern Kyrgyzstan. Remittances perform important social roles in sustaining social relations, making absent migrants present, gaining and/or retaining social status, passing through rites of passage and fostering the emergence of a new wealthy elite. Drawing on ethnographic research, the author examines the ambivalent opinions that surround the issue of migration and explores the idioms through which family absence is justified. The author argues that in addition to the important social functions of remittances, migrants' transfers in Sopu Korgon also help immediate family members to remain in the village and sustain their lives there. This in turn suggests that migrants' money slows up time for other family members, delaying their own need to migrate. © 2011 Copyright Southseries Inc. Source


Bion J.,University of Birmingham | Rothen H.U.,University of Bern
American Journal of Respiratory and Critical Care Medicine | Year: 2014

The diversity of European culture is reflected in its healthcare training programs. In intensive care medicine (ICM), the differences in national training programs were so marked that it was unlikely that they could produce specialists of equivalent skills. The Competency-Based Training in Intensive Care Medicine in Europe (CoBaTrICE) program was established in 2003 as a Europe-based worldwide collaboration of national training organizations to create core competencies for ICM using consensus methodologies to establish common ground. The group's professional and research ethos created a social identity that facilitated change. The program was easily adaptable to different training structures and incorporated the voice of patients and relatives. The CoBaTrICE program has now been adopted by 15 European countries, with another 12 countries planning to adopt the training program, and is currently available in nine languages, including English. ICMis nowrecognized as a primary specialty in Spain, Switzerland, and the UK. There are still wide variations in structures andprocesses of training in ICM across Europe, although there has been agreement on a set of common program standards. The combination of a common "product specification" for an intensivist, combined with persisting variation in the educational context in which competencies are delivered, provides a rich source of research inquiry. Pedagogic research in ICM could usefully focus on the interplay between educational interventions, healthcare systems and delivery, and patient outcomes, such as including whether competency-based program are associated with lower error rates, whether communication skills training is associated with greater patient and family satisfaction, how multisource feedback might best be used to improve reflective learning and teamworking, or whether increasing the proportion of specialists trained in acute care in the hospital at weekends results in better patient outcomes. Copyright © 2014 by the American Thoracic Society. Source


Producing a rich, personalized Web-based consultation tool for plastic surgeons and patients is challenging. (1) To develop a computer tool that allows individual reconstruction and simulation of 3-dimensional (3D) soft tissue from ordinary digital photos of breasts, (2) to implement a Web-based, worldwide-accessible preoperative surgical planning platform for plastic surgeons, and (3) to validate this tool through a quality control analysis by comparing 3D laser scans of the patients with the 3D reconstructions with this tool from original 2-dimensional (2D) pictures of the same patients. The proposed system uses well-established 2D digital photos for reconstruction into a 3D torso, which is then available to the user for interactive planning. The simulation is performed on dedicated servers, accessible via Internet. It allows the surgeon, together with the patient, to previsualize the impact of the proposed breast augmentation directly during the consultation before a surgery is decided upon. We retrospectively conduced a quality control assessment of available anonymized pre- and postoperative 2D digital photographs of patients undergoing breast augmentation procedures. The method presented above was used to reconstruct 3D pictures from 2D digital pictures. We used a laser scanner capable of generating a highly accurate surface model of the patient's anatomy to acquire ground truth data. The quality of the computed 3D reconstructions was compared with the ground truth data used to perform both qualitative and quantitative evaluations. We evaluated the system on 11 clinical cases for surface reconstructions and 4 clinical cases of postoperative simulations, using laser surface scan technologies showing a mean reconstruction error between 2 and 4 mm and a maximum outlier error of 16 mm. Qualitative and quantitative analyses from plastic surgeons demonstrate the potential of these new emerging technologies. We tested our tool for 3D, Web-based, patient-specific consultation in the clinical scenario of breast augmentation. This example shows that the current state of development allows for creation of responsive and effective Web-based, 3D medical tools, even with highly complex and time-consuming computation, by off-loading them to a dedicated high-performance data center. The efficient combination of advanced technologies, based on analysis and understanding of human anatomy and physiology, will allow the development of further Web-based reconstruction and predictive interfaces at different scales of the human body. The consultation tool presented herein exemplifies the potential of combining advancements in the core areas of computer science and biomedical engineering with the evolving areas of Web technologies. We are confident that future developments based on a multidisciplinary approach will further pave the way toward personalized Web-enabled medicine. Source


Delli K.,University of Bern
Quintessence international (Berlin, Germany : 1985) | Year: 2013

To systematically review the current literature on the maxillary midline frenum and associated conditions and complications, as well as the recommended treatment options. A detailed MEDLINE database search was carried out to provide evidence about the epidemiology, associated pathologies, and treatment options regarding the maxillary frenum. Of the 206 initially identified articles, 48 met the inclusion criteria. The maxillary frenum is highly associated with a number of syndromes and developmental abnormalities. A hypertrophic frenum may be involved in the etiology of the midline diastema. There is also a tendency by orthodontists to suggest posttreatment removal of the frenum (frenectomy). Studies on the cause of gingival recession due to the maxillary frenum are inconclusive. An injured frenum in combination with other traumas and doubtful history might point to child abuse. The involvement of hyperplastic frena in the pathogenesis of peri-implant diseases remains uncertain. There seems to be a clinical interest regarding lasers for surgery for treatment of maxillary frena. The superiority of laser treatment in relation to conventional surgical methods has not yet been demonstrated in the literature. A maxillary frenum is a clinical symptom in numerous syndromic conditions and plays a role in the development of the median midline diastema. Nevertheless, the contribution to gingival recession and peri-implant diseases in the region of the maxillary incisors is rather controversial. Laser techniques are reported as the method of choice for the surgical removal of frena; however, this needs to be substantiated by appropriate prospective controlled studies. Source


Simon A.E.,Specialized Early Psychosis Outpatient Service for Adolescents and Young Adults | Simon A.E.,University of Bern | Umbricht D.,Hoffmann-La Roche
Schizophrenia Research | Year: 2010

Objective: To investigate the proportion of patients among subjects initially identified as fulfilling the ultra-high risk (UHR) criteria for psychosis using the Scale of Prodromal Symptoms (SOPS) who fully remitted after one year. Method: Seventy-two patients between 14 and 40 years who were referred to the Bruderholz Early Psychosis Outpatient Service in Switzerland and who met UHR criteria were included in the present study. At 1-year follow-up, data for 52 patients were available. Patients with transition to psychosis and patients with sustained UHR criteria were defined as 'cases', and patients with remission from UHR criteria as 'non-cases'. We compared clinical and socio-demographic characteristics between these two patient groups at baseline. Results: 13.5% of the patients converted to full-blown psychosis within one year, one quarter displayed sustained UHR criteria, and 59.2% of the patients fully remitted from the initial UHR status. Outcome was independent of medication or treatment status. 'Cases' and 'non-cases' did not differ significantly on socio-demographic and clinical variables at baseline. Conclusions: The chance of remission to a non-risk state was over fourfold higher than the chance of conversion to psychosis within a year of establishing UHR status. Our data underline that the commonly used symptoms to identify UHR patients are often transitory and may not capture the stable core of developing psychosis. This highlights the danger of provoking anxiety and stigmatization in mislabeled individuals and missing true at-risk patients who present features of the psychosis core, but who do not yet-or maybe never will-manifest positive symptoms. © 2009 Elsevier B.V. All rights reserved. Source


Stirnimann G.,University of Bern
Swiss medical weekly : official journal of the Swiss Society of Infectious Diseases, the Swiss Society of Internal Medicine, the Swiss Society of Pneumology | Year: 2010

Although severe idiosyncratic drug-induced liver injury (DILI) is a rare event, it has a large impact on the fate of affected patients and the incriminated drug. Hepatic metabolism of drugs, which occurs in the generation of chemically reactive metabolites in critical amounts, seems to underlie most instances of DILI. Genetic polymorphisms in activating and detoxifying enzymes determine, in part, the extent of cellular stress. A cascade of events, where the pathogenetic relevance of single steps is likely to vary from drug to drug, leads to the disturbance of cellular homeostasis, to mitochondrial dysfunction, to the activation of cell death promoting pathways and the release of drug-modified macromolecules and/or danger signals that initiate an innate and/or adaptive immune response. The patient's response to the initial drug-induced cellular dysfunction determines whether adaptation to the drug-induced cellular stress or DILI in one of its many forms of clinical presentation occurs. Although risk factors for developing DILI have been identified and many pathogenetic mechanisms have been elucidated in model systems, idiosyncratic drug reactions remain unpredictable. Source


Nielsen E.,University of Bern
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2013

This study deals with faunal finds from the Swiss Paleolithic, especially from the Late Glacial. Faunal assemblages from archeological sites as well as off-site finds dated by scientific means are included. In the middle of the Oldest Dryas the large glacial species - mammoth, rhinoceros, cave bear, musk ox - become extinct. During the Early Bølling the last arctic species disappear, and are succeeded by animals like red deer and elk, preferring a moderate climate. From the middle of the Allerød, species typical of a denser forest (roe deer and wild boar) are very frequent. © 2012 Elsevier B.V. Source


Schlunegger F.,University of Bern | Norton K.P.,Victoria University of Wellington
Tectonophysics | Year: 2013

Recent studies have identified relationships between landscape form, erosion and climate in regions of landscape rejuvenation, associated with increased denudation. Most of these landscapes are located in non-glaciated mountain ranges and are characterized by transient geomorphic features. The landscapes of the Swiss Alps are likewise in a transient geomorphic state as seen by multiple knickzones. In this mountain belt, the transient state has been related to erosional effects during the Late Glacial Maximum (LGM). Here, we focus on the catchment scale and categorize hillslopes based on erosional mechanisms, landscape form and landcover. We then explore relationships of these variables to precipitation and extent of LGM glaciers to disentangle modern versus palaeo controls on the modern shape of the Alpine landscape. We find that in grasslands, the downslope flux of material mainly involves unconsolidated material through hillslope creep, testifying a transport-limited erosional regime. Alternatively, strength-limited hillslopes, where erosion is driven by bedrock failure, are covered by forests and/or expose bedrock, and they display oversteepened hillslopes and channels. There, hillslope gradients and relief are more closely correlated with LGM ice occurrence than with precipitation or the erodibility of the underlying bedrock. We relate the spatial occurrence of the transport- and strength-limited process domains to the erosive effects of LGM glaciers. In particular, strength-limited, rock dominated basins are situated above the equilibrium line altitude (ELA) of the LGM, reflecting the ability of glaciers to scour the landscape beyond threshold slope conditions. In contrast, transport-limited, soil-mantled landscapes are common below the ELA. Hillslopes covered by forests occupy the elevations around the ELA and are constrained by the tree line. We conclude that the current erosional forces at work in the Central Alps are still responding to LGM glaciation, and that the modern climate has not yet impacted on the modern landscape. © 2013 Elsevier B.V. Source


Allen S.,University of Bern | Huggel C.,University of Zurich
Global and Planetary Change | Year: 2013

A gradual reduction in the stability of steep bedrock slopes is recognized as one potential impact of warming in high mountain regions. Recently, consideration has turned to the potential direct role of extremely warm temperatures in triggering rockfalls. We provide here a first systematic assessment of the timing of 53 recent rockfalls relative to defined seasonal extremes of daily maximum air temperature. Rockfall observations from the Swiss Alps, Mont Blanc Massif, and Southern Alps of New Zealand, are combined with climate analyses based on the nearest available long-term records. At four high elevation climate stations in Switzerland, there has been significant warming across all quantiles of daily maximum temperature during the spring and summer months, with corresponding increases in both the frequency and magnitude of extremely warm days, and generally less warming (even cooling) during winter and autumn. In the same region, an unusually high occurrence of extremely warm days occurring in the week leading up to rockfalls has been observed over recent decades, with 14 out of 24 rockfalls preceded by one or more extremely warm days. At the neighboring Mont Blanc Massif, based on only two years of observations, few rockfalls can be linked to extremely warm temperatures, although an early and extremely warm onset of seasonal thawing in spring 2007 may have contributed to the large number of rockfalls observed that same summer. In the Southern Alps of New Zealand, the available evidence provides no basis to suggest extremely warm temperatures have triggered unusual rockfall activity. © 2013 Elsevier B.V.. Source


Leya I.,University of Bern | Masarik J.,Comenius University
Meteoritics and Planetary Science | Year: 2013

Neutron capture effects in meteorites and lunar surface samples have been successfully used in the past to study exposure histories and shielding conditions. In recent years, however, it turned out that neutron capture effects produce a nuisance for some of the short-lived radionuclide systems. The most prominent example is the 182Hf-182W system in iron meteorites, for which neutron capture effects lower the 182W/184W ratio, thereby producing too old apparent ages. Here, we present a thorough study of neutron capture effects in iron meteorites, ordinary chondrites, and carbonaceous chondrites, whereas the focus is on iron meteorites. We study in detail the effects responsible for neutron production, neutron transport, and neutron slowing down and find that neutron capture in all studied meteorite types is not, as usually expected, exclusively via thermal neutrons. In contrast, most of the neutron capture in iron meteorites is in the epithermal energy range and there is a significant contribution from epithermal neutron capture even in stony meteorites. Using sophisticated particle spectra and evaluated cross section data files for neutron capture reactions we calculate the neutron capture effects for Sm, Gd, Cd, Pd, Pt, and Os isotopes, which all can serve as neutron-dose proxies, either in stony or in iron meteorites. In addition, we model neutron capture effects in W and Ag isotopes. For W isotopes, the GCR-induced shifts perfectly correlate with Os and Pt isotope shifts, which therefore can be used as neutron-dose proxies and permit a reliable correction. We also found that GCR-induced effects for the 107Pd-107Ag system can be significant and need to be corrected, a result that is in contrast to earlier studies. © The Meteoritical Society, 2013. Source


Villa I.M.,University of Bern | Villa I.M.,University of Milan Bicocca | Hanchar J.M.,Memorial University of Newfoundland
Geochimica et Cosmochimica Acta | Year: 2013

The significance of the multi-isotopic record preserved in K-feldspars is assessed on samples from the Aar metagranite, Central Alps, Switzerland having very tight independent geological constraints. Stepwise leaching reveals that two diachronically grown K-feldspar generations coexist: Kfs-1 (≥35Ma old, Ca-poor, Rb-Cl-rich, with low 87Sr/86Sr and high 206Pb/204Pb) and Kfs-2 (≤10Ma old, antithetic isotopic signatures deriving from external fluids). Microtextures imaged by cathodoluminescence, backscattered electrons, and electron probe microanalysis are patchy and chemically heterogeneous, with pronounced enrichments in Ba in the retrogressed regions. This confirms the simultaneous presence of fluid-dominated retrogression and recrystallization and isotopic inheritance. The staircase-shaped 40Ar/39Ar age spectrum correlates with the Ca/K and Cl/K signatures. This reflects a mixture of heterochemical K-feldspar generations, and not an intracrystalline Ar gradient caused by diffusion. The shape of the age spectrum and the in vacuo release kinetics proceed from entirely different physical and geological phenomena.What K-feldspars can be effectively used for is to constrain the timing of the fluids that interacted with them by multi-isotopic analyses, rather than to model a " cooling history" from 39Ar release alone. The identification of multiple mineral generations by imaging combined with multi-isotopic analysis enables the accurate dating of the events of a multistage evolution after the initial crystallization of the rock in which the minerals occur. © 2012 Elsevier Ltd. Source


Sfetsos K.,National and Kapodistrian University of Athens | Siampos K.,University of Bern
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2015

The all-loop anisotropic Thirring model interpolates between the WZW model and the non-Abelian T-dual of the anisotropic principal chiral model. We focus on the SU(2) case and we prove that it is classically integrable by providing its Lax pair formulation. We derive its underlying symmetry current algebra and use it to show that the Poisson brackets of the spatial part of the Lax pair, assume the Maillet form. In this way we procure the corresponding r and s matrices which provide non-trivial solutions to the modified Yang-Baxter equation. © 2015 The Authors. Source


Hollenstein M.,University of Bern
Organic and Biomolecular Chemistry | Year: 2015

Rolling Circle Amplification (RCA) is an isothermal enzymatic method generating single-stranded DNA products consisting of concatemers containing multiple copies of the reverse complement of the circular template precursor. Little is known on the compatibility of modified nucleoside triphosphates (dN∗TPs) with RCA, which would enable the synthesis of long, fully modified ssDNA sequences. Here, dNTPs modified at any position of the scaffold were shown to be compatible with rolling circle amplification, yielding long (>1 kb), and fully modified single-stranded DNA products. This methodology was applied for the generation of long, cytosine-rich synthetic mimics of telomeric DNA. The resulting modified oligonucleotides displayed an improved resistance to fetal bovine serum. © The Royal Society of Chemistry 2015. Source


Rutte C.,University of Bern
Biological Conservation | Year: 2011

Sacred natural sites are considered an additional pillar for biodiversity conservation, next to the protected areas network. However, sacred landscapes are not primarily conservation areas, but exist for cultural and social reasons. To evaluate their strengths and weaknesses as community-based conservation areas, a thorough understanding of the underlying values, institutional arrangements, and outcomes is required. Here, I use institutional economics for a meta-analysis of publications on sacred natural sites to identify potential conflicts in their maintenance, and to analyze institutional arrangements to solve these conflicts. I show that most sacred natural sites resemble common-pool resources and that many design principles that are linked to common-pool resources are also found in traditional institutions managing sacred places. Design principles are no blue-print solution but they may guide future research to identify locally robust institutional arrangements that are linked to the ecological integrity of sacred natural sites. © 2011 Elsevier Ltd. Source


Slatkin M.,University of California at Berkeley | Excoffier L.,University of Bern | Excoffier L.,Swiss Institute of Bioinformatics
Genetics | Year: 2012

Range expansions cause a series of founder events. We show that, in a one-dimensional habitat, these founder events are the spatial analog of genetic drift in a randomly mating population. The spatial series of allele frequencies created by successive founder events is equivalent to the time series of allele frequencies in a population of effective size ke, the effective number of founders. We derive an expression for ke in a discrete-population model that allows for local population growth and migration among established populations. If there is selection, the net effect is determined approximately by the product of the selection coefficients and the number of generations between successive founding events. We use the model of a single population to compute analytically several quantities for an allele present in the source population: (i) the probability that it survives the series of colonization events, (ii) the probability that it reaches a specified threshold frequency in the last population, and (iii) the mean and variance of the frequencies in each population. We show that the analytic theory provides a good approximation to simulation results. A consequence of our approximation is that the average heterozygosity of neutral alleles decreases by a factor of 1 - 1/(2ke) in each new population. Therefore, the population genetic consequences of surfing can be predicted approximately by the effective number of founders and the effective selection coefficients, even in the presence of migration among populations. We also show that our analytic results are applicable to a model of range expansion in a continuously distributed population. © 2012 by the Genetics Society of America. Source


Nunes L.S.,University of Bern
The International journal of periodontics & restorative dentistry | Year: 2013

The purpose of this study was to analyze the width and height of edentulous sites in the posterior maxilla using cone beam computed tomography (CBCT) images from patients referred for implant therapy. A total of 122 CBCT scans were included in the analysis, resulting in a sample size of 252 edentulous sites. The orofacial crest width was measured in coronal slices, perpendicular to the alveolar ridge. The bone height was analyzed in the respective sagittal slices. Additionally, the following secondary outcome parameters were evaluated: the morphology of the sinus floor, the presence of septa in the maxillary sinus, and the thickness of the sinus membrane. The mean crest width for all analyzed sites was 8.28 mm, and the mean bone height was 7.22 mm. The percentage of patients with a crest width of less than 6 mm was 27% in premolar sites and 7.8% in molar sites. The bone height decreased from premolar to molar areas, with a high percentage of first and second molar sites exhibiting a bone height of less than 5 mm (54.12% and 44.64%, respectively). Regarding the morphology of the sinus floor, 53% of the edentulous sites exhibited a flat configuration. A septum was present in 67 edentulous sites (26.59%). Analysis of the sinus membrane revealed 88 sites (34.9%) with increased mucosal thickness (> 2 mm). For the crest width, the location of the edentulous site and the morphology of the sinus floor were both statistically significant variables. For the crest width and mean bone height, the location of the edentulous site and the morphology of the sinus floor were both statistically significant variables. The study confirmed that a high percentage of edentulous sites in the posterior maxilla do require sinus floor elevation to allow the placement of dental implants. Therefore, a detailed three-dimensional radiograph using CBCT is indicated in most patients for proper treatment planning. Source


Stoffel M.,University of Bern | Huggel C.,University of Geneva
Progress in Physical Geography | Year: 2012

Changes in temperature and precipitation have a range of impacts, including change of glacier extent, extent and duration of snow cover, and distribution and thermal properties of permafrost. Similarly, it is likely that climatic changes affect frequency and magnitude of mass movements, such as shallow landslides, debris flows, rock slope failures, or ice avalanches. However, so far changes in mass-movement activity can hardly be detected in observational records. In this progress report we document the role of climate variability and change on mass-movement processes in mountains through the description and analysis of selected, recent mass movements where effects of global warming and the occurrence of heavy precipitation are thought to have contributed to, or triggered, events. In addition, we assess possible effects of future climatic changes on the incidence of mass-movement processes. The report concentrates on high-mountain systems, including processes such as glacier downwasting and the formation of new ice-marginal lakes, glacier debuttressing and the occurrence of rock slope instability, temperature increase and permafrost degradation, as well as on changing sediment reservoirs and sediment supply, with a clear focus on studies from the European Alps. © The Author(s) 2012. Source


Benarafa C.,University of Bern
Breast Cancer Research | Year: 2015

Neutrophils are essential to combat infectious agents but contribute to collateral inflammatory damage. Likewise, neutrophils can kill cancer cells and have been shown to promote malignant growth and metastasis through immunosuppressive functions. Two articles in a recent issue of Nature reveal new mechanisms by which tumors induce changes in neutrophil phenotype through production of inflammatory cytokines. Although the two studies report different outcomes on the effects of neutrophils on tumor growth and metastasis, they delineate novel molecular pathways influencing neutrophil phenotype that may provide new approaches to harnessing neutrophil functions in the treatment of cancer. © 2015 Benarafa. Source


Aebi M.,University of Bern
European Spine Journal | Year: 2010

A classification of injuries is necessary in order to develop a common language for treatment indications and outcomes. Several classification systems have been proposed, the most frequently used is the Denis classification. The problem of this classification system is that it is based on an assumption, which is anatomically unidentifiable: the so-called middle column. For this reason, few years ago, a group of spine surgeons has developed a new classification system, which is based on the severity of the injury. The severity is defined by the pathomorphological findings, the prognosis in terms of healing and potential of neurological damage. This classification is based on three major groups: A = isolated anterior column injuries by axial compression, B = disruption of the posterior ligament complex by distraction posteriorly, and group C = corresponding to group B but with rotation. There is an increasing severity from A to C, and within each group, the severity usually increases within the subgroups from .1, .2, .3. All these pathomorphologies are supported by a mechanism of injury, which is responsible for the extent of the injury. The type of injury with its groups and subgroups is able to suggest the treatment modality. © Springer-Verlag 2009. Source


Frohlich K.L.,University of Montreal | Abel T.,University of Bern
Sociology of Health and Illness | Year: 2014

While empirical evidence continues to show that people living in low socio-economic status neighbourhoods are less likely to engage in health-enhancing behaviour, our understanding of why this is so remains less than clear. We suggest that two changes could take place to move from description to understanding in this field; (i) a move away from the established concept of individual health behaviour to a contextualised understanding of health practices; and (ii) a switch from focusing on health inequalities in outcomes to health inequities in conditions. We apply Pierre Bourdieu's theory on capital interaction but find it insufficient with regard to the role of agency for structural change. We therefore introduce Amartya Sen's capability approach as a useful link between capital interaction theory and action to reduce social inequities in health-related practices. Sen's capability theory also elucidates the importance of discussing unequal chances in terms of inequity, rather than inequality, in order to underscore the moral nature of inequalities. We draw on the discussion in social geography on environmental injustice, which also underscores the moral nature of the spatial distribution of opportunities. The article ends by applying this approach to the 'Interdisciplinary study of inequalities in smoking' framework. © 2013 Foundation for the Sociology of Health & Illness/John Wiley & Sons Ltd. Source


Adamantidis A.R.,University of Bern | Adamantidis A.R.,McGill University
Current Biology | Year: 2015

Besides the master clock located in the suprachiasmatic nucleus (SCN) of the brain, additional clocks are distributed across the central nervous system and the body. The role of these 'secondary' clocks remains unclear. A new study shows that the lack of an internal clock in histamine neurons profoundly perturbs sleep. © 2015 Elsevier Ltd. All rights reserved. Source


Stoffel M.,University of Bern | Stoffel M.,University of Geneva | Wilford D.J.,British Columbia Ministry of Natural Resource Operations
Earth Surface Processes and Landforms | Year: 2012

Riparian vegetation and hydrogeomorphic processes are intimately connected parts of upland catchment and fan environments. Trees, shrubs and grasses and hydrogeomorphic processes interact and depend on each other in complex ways on the hillslopes, channels and cone-shaped fans of torrential watersheds. While the presence and density of vegetation have a profound influence on hydrogeomorphic processes, the occurrence of the latter will also exert control on the presence, vitality, species, and age distribution of vegetation. This contribution aims at providing a review of foundational and more recent work on the dependencies and interactions between hydrogeomorphic processes and vegetation. In particular, we address the role of vegetation in the initiation of hydrogeomorphic processes and its impact on stream morphology as well as immediate and long-term effects of hydrogeomorphic disturbance on vegetation. © 2011 John Wiley & Sons, Ltd. Source


Calzaferri G.,University of Bern
Langmuir | Year: 2012

Nanochannels have been used as hosts for supramolecular organization for a large variety of guests. The possibilities for building complex structures based on 2D and especially 3D nanochannel hosts are larger than those based on 1D nanochannel hosts. The latter are, however, easier to understand and to control. They still give rise to a rich world of fascinating objects with very distinguished properties. Important changes are observed if the channel diameter becomes smaller than 10 nm. The most advanced guest-nanochannel composites have been synthesized with nanochannels bearing a diameter of about 1 nm. Impressive complexity has been achieved by interfacing these composites with other objects and by assembling them into specific structures. This is explained in detail. Guest-nanochannel composites that absorb all light in the right wavelength range and transfer the electronic excitation energy via FRET to well-positioned acceptors offer a unique potential for developing FRET-sensitized solar cells, luminescent solar concentrators, color-changing media, and devices for sensing in analytical chemistry, biology, and diagnostics. Successful 1D nanochannel hosts for synthesizing guest-host composites have been zeolite-based. Among them the largest variety of guest-zeolite composites with appealing photochemical, photophysical, and optical properties has been prepared by using zeolite L (ZL) as a host. The reasons are the various possibilities for fine tuning the size and morphology of the particles, for inserting neutral molecules and cations, and for preparing rare earth complexes inside by means of the ship-in-a-bottle procedure. An important fact is that the channel entrances of ZL-based composites can be functonalized and completely blocked, if desired, and furthermore that targeted functionalization of the coat is possible. Different degrees of organizational levels and prospects for applications are discussed, with special emphasis on solar energy conversion devices. © 2012 American Chemical Society. Source


Gashti M.P.,University of Bern | Almasian A.,Islamic Azad University at South Tehran
Composites Part B: Engineering | Year: 2012

Silver was loaded on silica/kaolinite by photo-reduction technique. The present study investigated the effects of the UV irradiation on different characteristics of the particles employing X-ray diffraction (XRD), Fourier-transform infrared spectra (FTIR), UV-vis spectrophotometer (UVS), Brunauer-Emmett-Teller specific surface area method (BETM), zeta potential measurement (ZPM), thermal gravimetric analysis (TGA), scanning electron microscope (SEM), electron dispersive X-ray spectrometer (EDX) and electromagnetic transition instrument (ETI). XRD, FTIR as well as UV absorption methods evidenced that synthesizing procedure was successful under UV irradiation. TGA results demonstrated that the Ag nanoparticles (AgNPs) generated on the silica/kaolinite surface can decrease thermal stability of particles due to proton delocalization of hydroxyl groups and Hofmann-Klemen effect. EDX results showed the presence of chemical elements namely Fe, Al, Si, Mg, K, Ti, Ag, Ca and Fe on the surface of tertiary nanocomposite. The synthesized silver/silica/kaolinite particles were found to have a higher electromagnetic absorption activity compared with silica/kaolinite. As a result, they can be used in polymer-based composites for preparing high performance electromagnetic interference shielding materials. © 2011 Elsevier Ltd. All rights reserved. Source


O'Brien D.P.,University of Missouri | Leeb T.,University of Bern
Journal of Veterinary Internal Medicine | Year: 2014

DNA testing is available for a growing number of hereditary diseases in neurology and other specialties. In addition to guiding breeding decisions, DNA tests are important tools in the diagnosis of diseases, particularly in conditions for which clinical signs are relatively nonspecific. DNA testing also can provide valuable insight into the risk of hereditary disease when decisions about treating comorbidities are being made. Advances in technology and bioinformatics will make broad screening for potential disease-causing mutations available soon. As DNA tests come into more common use, it is critical that clinicians understand the proper application and interpretation of these test results. © 2014 by the American College of Veterinary Internal Medicine. Source


Silber S.,Heart Center at the Isar | Windecker S.,University of Bern | Vranckx P.,Hartcentrum Hasselt | Serruys P.W.,Rotterdam University
The Lancet | Year: 2011

In the RESOLUTE All Comers trial, the Resolute zotarolimus-eluting stent was non-inferior to the Xience V everolimus-eluting stent for the primary stent-related endpoint of target lesion failure (cardiac death, target vessel myocardial infarction, and ischaemia-driven target lesion revascularisation) at 1 year. However, data for long-term safety and efficacy from randomised studies of new generation drug-eluting coronary stents in patients treated in routine clinical practice are scarce. We report the prespecified 2-year clinical outcomes from the RESOLUTE All Comers trial. In 2008, patients with at least one coronary lesion 2·25-4·0 mm in diameter, with greater than 50 stenosis, were randomly assigned to a Resolute zotarolimus-eluting stent or a Xience V everolimus-eluting stent at 17 centres in Europe and Israel. Randomisation was by an interactive voice response system stratified by centre. Study investigators were not masked to treatment allocation; but those who did data management and analysis, and patients were masked. There were no restrictions as to the number of vessels or lesions treated, or the number of stents implanted. We assessed prespecified safety and efficacy outcomes at 2 years with specific focus on patient-related composite (all death, all myocardial infarction, all revascularisation) and stent-related composite outcomes. Analyses were by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00617084. 1140 patients were assigned to the zotarolimus-eluting stent and 1152 to the everolimus-eluting stent; 1121 and 1128 patients, respectively, completed 2-year follow-up. The patient-related outcome (231 [20·6] zotarolimus vs 231 [20·5] everolimus; difference 0·1, 95 CI -3·2 to 3·5; p=0·958) and stent-related outcome (126 [11·2] vs 121 [10·7]; difference 0·5, -2·1 to 3·1; p=0·736) did not differ between groups, although rates of the stent-related outcome were substantially lower than were those for the patient-related outcome. Three patients in each group (0·3) had very late (after 1 year) stent thrombosis. Similar safety and efficacy outcomes were sustained between two new generation drug-eluting stents at 2-year follow-up. The greater number of patient-related than stent-related events in patients with complex clinical and lesion characteristics emphasises that during long-term follow-up, the optimisation of secondary prevention is at least as important as the selection of which new generation drug-eluting stent to implant in a specific lesion. Medtronic (USA). © 2011 Elsevier Ltd. Source


Excoffier L.,University of Bern | Lischer H.E.L.,Swiss Institute of Bioinformatics
Molecular Ecology Resources | Year: 2010

We present here a new version of the Arlequin program available under three different forms: a Windows graphical version (W. inarl35), a console version of Arlequin (arlecore), and a specific console version to compute summary statistics (arlsumstat). The command-line versions run under both Linux and Windows. The main innovations of the new version include enhanced outputs in XML format, the possibility to embed graphics displaying computation results directly into output files, and the implementation of a new method to detect loci under selection from genome scans. Command-line versions are designed to handle large series of files, and arlsumstat can be used to generate summary statistics from simulated data sets within an Approximate Bayesian Computation framework. © 2010 Blackwell Publishing Ltd. Source


Erol R.Y.,University of Basel | Orth U.,University of Bern
Developmental psychology | Year: 2014

We examined the effects of self-esteem development on the development of relationship satisfaction in 2 samples of couples. Study 1 used data from both partners of 885 couples assessed 5 times over 12 years, and Study 2 used data from both partners of 6,116 couples assessed 3 times over 15 years. The pattern of results was similar across the 2 studies. First, development of relationship satisfaction could be modeled as a couple-level process. Second, initial level of self-esteem of each partner predicted the initial level of the partners' common relationship satisfaction, and change in self-esteem of each partner predicted change in the partners' common relationship satisfaction. Third, these effects did not differ by gender and held when controlling for participants' age, length of relationship, health, and employment status. Fourth, self-esteem similarity among partners did not influence the development of their relationship satisfaction. The findings suggest that the development of self-esteem in both partners of a couple contributes in a meaningful way to the development of the partners' common satisfaction with their relationship. Source


Patients with peritonitis undergoing emergency laparotomy are at increased risk for postoperative open abdomen and incisional hernia. This study aimed to evaluate the outcome of prophylactic intraperitoneal mesh implantation compared with conventional abdominal wall closure in patients with peritonitis undergoing emergency laparotomy. A matched case-control study was performed. To analyze a high-risk population for incisional hernia formation, only patients with at least two of the following risk factors were included: male sex, body mass index (BMI) >25 kg/m(2), malignant tumor, or previous abdominal incision. In 63 patients with peritonitis, a prophylactic nonabsorbable mesh was implanted intraperitoneally between 2005 and 2010. These patients were compared with 70 patients with the same risk factors and peritonitis undergoing emergency laparotomy over a 1-year period (2008) who underwent conventional abdominal closure without mesh implantation. Demographic parameters, including sex, age, BMI, grade of intraabdominal infection, and operating time were comparable in the two groups. Incidence of surgical site infections (SSIs) was not different between groups (61.9 vs. 60.3 %; p = 0.603). Enterocutaneous fistula occurred in three patients in the mesh group (4.8 %) and in two patients in the control group (2.9 %; p = 0.667). The incidence of incisional hernia was significantly lower in the mesh group (2/63 patients) than in the control group (20/70 patients) (3.2 vs. 28.6 %; p < 0.001). Prophylactic intraperitoneal mesh can be safely implanted in patients with peritonitis. It significantly reduces the incidence of incisional hernia. The incidences of SSI and enterocutaneous fistula formation were similar to those seen with conventional abdominal closure. Source


Nowacki M.,University of Bern | Shetty K.,Princeton University | Landweber L.F.,Princeton University
Annual Review of Genomics and Human Genetics | Year: 2011

RNA, normally thought of as a conduit in gene expression, has a novel mode of action in ciliated protozoa. Maternal RNA templates provide both an organizing guide for DNA rearrangements and a template that can transport somatic mutations to the next generation. This opportunity for RNA-mediated genome rearrangement and DNA repair is profound in the ciliate Oxytricha, which deletes 95% of its germline genome during development in a process that severely fragments its chromosomes and then sorts and reorders the hundreds of thousands of pieces remaining. Oxytricha's somatic nuclear genome is therefore an epigenome formed through RNA templates and signals arising from the previous generation. Furthermore, this mechanism of RNA-mediated epigenetic inheritance can function across multiple generations, and the discovery of maternal template RNA molecules has revealed new biological roles for RNA and has hinted at the power of RNA molecules to sculpt genomic information in cells. © 2011 by Annual Reviews. All rights reserved. Source


Richards C.L.,University of South Florida | Bossdorf O.,University of Bern | Pigliucci M.,City University of New York
BioScience | Year: 2010

To explore the potential evolutionary relevance of heritable epigenetic variation, the National Evolutionary Synthesis Center recently hosted a catalysis meeting that brought together molecular epigeneticists, experimental evolutionary ecologists, and theoretical population and quantitative geneticists working across a wide variety of systems. The group discussed the methods available to investigate epigenetic variation and epigenetic inheritance, and how to evaluate their importance for phenotypic evolution. We found that understanding the relevance of epigenetic effects in phenotypic evolution will require clearly delineating epigenetics within existing terminology and expanding research efforts into ecologically relevant circumstances across model and nonmodel organisms. In addition, a critical component of understanding epigenetics will be the development of new and current statistical approaches and expansion of quantitative and population genetic theory. Although the importance of heritable epigenetic effects on evolution is still under discussion, investigating them in the context of a multidisciplinary approach could transform the field. © 2010 by American Institute of Biological Sciences. All rights reserved. Source


Zuppinger C.,University of Bern
Biochimica et Biophysica Acta - Molecular Cell Research | Year: 2015

This review discusses historical milestones, recent developments and challenges in the area of 3D culture models with cardiovascular cell types. Expectations in this area have been raised in recent years, but more relevant in vitro research, more accurate drug testing results, reliable disease models and insights leading to bioartificial organs are expected from the transition to 3D cell culture. However, the construction of organ-like cardiac 3D models currently remains a difficult challenge. The heart consists of highly differentiated cells in an intricate arrangement. Furthermore, electrical "wiring", a vascular system and multiple cell types act in concert to respond to the rapidly changing demands of the body. Although cardiovascular 3D culture models have been predominantly developed for regenerative medicine in the past, their use in drug screening and for disease models has become more popular recently. Many sophisticated 3D culture models are currently being developed in this dynamic area of life science. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel. © 2015 Elsevier B.V. Source


Merchant P.,University College London | Normand B.,Renmin University of China | Kramer K.W.,University of Bern | Boehm M.,Laue Langevin Institute | And 4 more authors.
Nature Physics | Year: 2014

A quantum critical point (QCP) is a singularity in the phase diagram arising because of quantum mechanical fluctuations. The exotic properties of some of the most enigmatic physical systems, including unconventional metals and superconductors, quantum magnets and ultracold atomic condensates, have been related to the importance of critical quantum and thermal fluctuations near such a point. However, direct and continuous control of these fluctuations has been difficult to realize, and complete thermodynamic and spectroscopic information is required to disentangle the effects of quantum and classical physics around a QCP. Here we achieve this control in a high-pressure, high-resolution neutron scattering experiment on the quantum dimer material TlCuCl 3. By measuring the magnetic excitation spectrum across the entire quantum critical phase diagram, we illustrate the similarities between quantum and thermal melting of magnetic order. We prove the critical nature of the unconventional longitudinal (Higgs) mode of the ordered phase by damping it thermally. We demonstrate the development of two types of criticality, quantum and classical, and use their static and dynamic scaling properties to conclude that quantum and thermal fluctuations can behave largely independently near a QCP. © 2014 Macmillan Publishers Limited. Source


Dooley T.P.,University of Texas at Austin | Schreurs G.,University of Bern
Tectonophysics | Year: 2012

Intraplate strike-slip zones commonly display intricate 3-D geometries, with rapid changes in structural style along strike and with depth. Strike-slip deformation typically results in complex vertical and horizontal sections that can be difficult to interpret coherently. Physical modelling of strike-slip fault systems is a powerful and graphic tool to help in providing a unified picture of the evolution of strike-slip zones with considerable spatial and temporal detail. A large number of experimental studies have investigated different aspects of strike-slip tectonics using materials such as dry sand, wet clay, or silicone. The choice of analogue material and experimental design exerts a strong control on the structures that form in the model.Here we present a review of different experimental setups used to investigate intraplate strike-slip tectonics, from the classical Riedel experiment to more sophisticated setups using brittle and viscous analogue materials. We review our current understanding from models of distributed shear, transtension, transpression, pull-apart basins formed in releasing stepovers, and popups formed in restraining stepovers. In addition, we present the results of two new experimental series that investigated (1) the effect of crustal weak zones on strike-slip fault-zone segmentation and (2) strike-slip and transpressional reactivation of extensional basins. © 2012 Elsevier B.V. Source


Jeger F.B.,University of Bern
Schweizer Monatsschrift für Zahnmedizin = Revue mensuelle suisse d'odonto-stomatologie = Rivista mensile svizzera di odontologia e stomatologia / SSO | Year: 2013

Since the introduction of cone beam computed tomography (CBCT), this 3-dimensional diagnostic imaging technique has been established in a growing number of fields in dental medicine. It has become an important tool for both diagnosis and treatment planning, and is also able to support endodontic treatments. However, the higher effective dose of ionizing radiation compared to conventional 2-dimensional radiographs is not justifiable in every case. CBCT allows for a more precise diagnosis of periapical lesions, root fractures as well as external and internal resorptions. Concerning the utility of CBCT in treatment planning decisions, the gain of information through 3-dimensional imaging for any of these pathologies has to be evaluated carefully on an individual basis. Moreover, radioopaque materials such as root canal filling and posts often create artefacts, which may compromise diagnosis. The aim of this review is to summarize the possibilities and limits of CBCT imaging in endodontology as well as introduce guidelines for daily clinical practice. Furthermore, the article presents possible therapeutic advantages of preexisting CBCT scans for root canal treatments. Source


Dudda M.,University of Bern
Journal of orthopaedic surgery (Hong Kong) | Year: 2010

To evaluate risk factors for early dislocation after primary total hip arthroplasty (THA). Records of 175 cases with dislocation during hospitalisation after THA and 651 controls without dislocation were reviewed. Cases and controls were matched for age, gender, body mass index classification, primary diagnosis, cup design, hospital, and year of intervention. Version and inclination of the acetabular component and version of the femoral component were assessed intra- and post-operatively. Various risk factors were analysed, including surgical approach, cup positioning, combined cup and stem positioning, and femoral head size. The posterior approach was 6 fold more prone to dislocation (odds ratio [OR]=6.3, p<0.018) than the anterolateral or straight lateral approach. With regard to combined cup and stem positioning, the acceptable position was at significantly higher risk of dislocation than the ideal position (OR=2.59, p=0.033). Larger femoral head sizes were associated with significantly lower risk of dislocation (OR=0.84, p=0.02). Surgical approach, combined cup and stem positioning, and femoral head size were significant risk factors for dislocation during hospitalisation. Source


Garzoni C.,University of Bern | Kelley W.L.,University of Geneva
EMBO Molecular Medicine | Year: 2011

Staphylococcus aureus small colony variants (SCVs), which are characterized by slow growth and a range of morphological and metabolic changes including altered antibiotic resistance profiles, have been studied for several decades. This Closeup highlights findings described in this issue of EMBO Molecular Medicine by Tuchscherr et al (2011), who present strong evidence that SCVs can arise in chronic infection models when S. aureus is internalized in non-professional phagocytes and survives intracellularly. As the intracellular residency time increases, the proportion of SCVs grows and the host cell inflammatory response diminishes. The study suggests that this mode of phenotype switching is an essential feature of the S. aureus infection process and can explain an underlying cause of chronic and relapsing infections. See related article in EMBO Mol Med (Tuchscherr et al (2011) EMBO Mol Med 3: 129-141) Copyright © 2011 EMBO Molecular Medicine. Source


Fleming L.,Imperial College London | Tsartsali L.,Royal Brompton Hospital | Wilson N.,Royal Brompton Hospital | Regamey N.,University of Bern | Bush A.,Imperial College London
Thorax | Year: 2012

Background: Two distinct, stable inflammatory phenotypes have been described in adults with asthma: eosinophilic and non-eosinophilic. Treatment strategies based on these phenotypes have been successful. This study evaluated sputum cytology in children with asthma to classify sputum inflammatory phenotypes and to assess their stability over time. Methods Sputum induction was performed in 51 children with severe asthma and 28 with mild to moderate asthma. Samples were classified as eosinophilic (>2.5% eosinophils), neutrophilic (>54% neutrophils); mixed granulocytic (>2.5% eosinophils, >54% neutrophils); or paucigranulocytic (≤2.5% eosinophils, ≤54% neutrophils). Sputum induction was repeated every 3 months in children with severe asthma (n=42) over a 1-year period and twice in mild to moderate asthma (n=17) over 3-6 months. Results: 62 children (78%) had raised levels of inflammatory cells in at least one sputum sample. In the longitudinal analysis 37 of 59 children (63%) demonstrated two or more phenotypes. Variability in sputum inflammatory phenotype was observed in both the severe and the mild to moderate asthma groups. Change in phenotype was not related to change in inhaled corticosteroid (ICS) dose or asthma control, nor was it reflected in a change in exhaled nitric oxide (FE NO). 24 children (41%) fulfilled the criteria for non-eosinophilic asthma on one occasion and eosinophilic on another. There were no differences in severity, asthma control, atopy, ICS dose or forced expiratory volume in 1 s between those who were always non-eosinophilic and those always eosinophilic. Conclusion: Raised levels of inflammatory cells were frequently found in children with asthma of all severities. Sputum inflammatory phenotype was not stable in children with asthma. Source


Barke A.,University of Gottingen | Nyarko S.,Albert Ludwigs University of Freiburg | Klecha D.,University of Bern
Social Psychiatry and Psychiatric Epidemiology | Year: 2011

Purpose Stigma is a frequent accompaniment of mental illness leading to a number of detrimental consequences. Most research into the stigma connected to mental illness was conducted in the developed world. So far, few data exist on countries in sub-Saharan Africa and no data have been published on population attitudes towards mental illness in Ghana. Even less is known about the stigma actually perceived by the mentally ill persons themselves. Method A convenience sample of 403 participants (210 men, mean age 32.4 ± 12.3 years) from urban regions in Accra, Cape Coast and Pantang filled in the Community Attitudes towards the Mentally Ill (CAMI) questionnaire. In addition, 105 patients (75 men, mean age 35.9 ± 11.0 years) of Ghana's three psychiatric hospitals (Accra Psychiatry Hospital, Ankaful Hospital, Pantang Hospital) answered the Perceived Stigma and Discrimination Scale. Results High levels of stigma prevailed in the population as shown by high proportions of assent to items expressing authoritarian and socially restrictive views, coexisting with agreement with more benevolent attitudes. A higher level of education was associated with more positive attitudes on all subscales (Authoritarianism, Social Restrictiveness, Benevolence and Acceptance of Community Based Mental Health Services). The patients reported a high degree of experienced stigma with secrecy concerning the illness as a widespread coping strategy. Perceived stigma was not associated with sex or age. Discussion The extent of stigmatising attitudes within the urban population of Southern Ghana is in line with the scant research in other countries in sub-Saharan Africa and mirrored by the experienced stigma reported by the patients. These results have to be seen in the context of the extreme scarcity of resources within the Ghanaian psychiatric system. Anti-stigma efforts should include interventions for mentally ill persons themselves and not exclusively focus on public attitudes. © The Author(s) 2010. Source


Tutuian R.,University of Bern
Best Practice and Research: Clinical Gastroenterology | Year: 2010

Given the function of the esophagus to transport orally ingested solids and liquids into the stomach there are several medications with adverse effect on esophageal structures and function. Various pharmacologic agents can induce esophageal injury, promote gastroesophageal reflux by decreasing lower esophageal sphincter tone or affect esophageal perception and motility. The risks of bisphosphonates, doxycycline, ferrous sulfate, ascorbic acid, aspirin/NSAIDs and chemotherapeutic agents to induce esophageal lesions have been documented in case reports and short series. In addition to direct mucosal injury, many commonly used medications including nitroglycerins, anticholinergics, β-adrenergic agonists, aminophyllines, and benzodiazepines promote/facilitate gastroesophageal reflux by reducing lower esophageal sphincter pressure. Additional evidence accumulates on the adverse effects of various medications on esophageal motility and perception. The treatment of medication-induced esophageal lesions includes (1) identifying and discontinuing the causative medication, (2) promoting healing of esophageal injury by decreasing esophageal acid exposure or coating already existing esophageal lesions, (3) eventual use of protective compounds. © 2010 Elsevier Ltd. All rights reserved. Source


Shaha M.,University of Bern
Nurse researcher | Year: 2011

Focus groups are increasingly popular in nursing research. However, proper care and attention are critical to their planning and conduct, particularly those involving nursing staff. This article uses data gleaned from prior research to address the complexities present in clinical settings when conducting focus groups with nurses. Applying their combined experiences of conducting studies with nursing staff, the authors present a data-derived approach to thorough preparation and successful implementation of focus group research, offering a unique contribution to the literature regarding this research strategy. Source


Volken E.,Proclim | Bronnimann S.,University of Bern
Meteorologische Zeitschrift | Year: 2011

This is the translated and edited version of the paper "Die Wärmezonen der Erde, nach der Dauer der heissen, gemässigten und kalten Zeit und nach der Wirkung der Wärme auf die organische Welt betrachtet" by W. Köppen, which originally appeared in 1884 in the Meteorologische Zeitschrift. Superscript numbers indicate original footnotes (translated at the bottom of the page), E⋯ numbers indicate editorial endnotes (at the end of the article), square brackets [] indicate editorial comments in the text. © Gebrüder Borntraeger, Berlin, Stuttgart 2011. Source


Gollwitzer E.S.,University of Lausanne | Saglani S.,UK National Heart and Lung Institute | Trompette A.,University of Lausanne | Yadava K.,University of Lausanne | And 5 more authors.
Nature Medicine | Year: 2014

Epidemiological data point toward a critical period in early life during which environmental cues can set an individual on a trajectory toward respiratory health or disease. The neonatal immune system matures during this period, although little is known about the signals that lead to its maturation. Here we report that the formation of the lung microbiota is a key parameter in this process. Immediately following birth, neonatal mice were prone to develop exaggerated airway eosinophilia, release type 2 helper T cell cytokines and exhibit airway hyper-responsiveness following exposure to house dust mite allergens, even though their lungs harbored high numbers of natural CD4 + Foxp3 + CD25 + Helios + regulatory T (T reg) cells. During the first 2 weeks after birth, the bacterial load in the lungs increased, and representation of the bacterial phyla shifts from a predominance of Gammaproteobacteria and Firmicutes towards Bacteroidetes. The changes in the microbiota were associated with decreased aeroallergen responsiveness and the emergence of a Helios a ̂' T reg cell subset that required interaction with programmed death ligand 1 (PD-L1) for development. Absence of microbial colonization 10 or blockade of PD-L1 during the first 2 weeks postpartum maintained exaggerated responsiveness to allergens through to adulthood. Adoptive transfer of T reg cells from adult mice to neonates before aeroallergen exposure ameliorated disease. Thus, formation of the airway microbiota induces regulatory cells early in life, which, when dysregulated, can lead to sustained susceptibility to allergic airway inflammation in adulthood. © 2014 Nature America, Inc. All rights reserved. Source


Solving the riddle of a thrombocytopenic patient is a difficult and fascinating task. The spectrum of possible aetiologies is wide, ranging from an in vitro artefact to severe treatment-resistant thrombocytopenic bleeding conditions, or even life-threatening prothrombotic states. Moreover, thrombocyto - penia by itself does not protect from thrombosis and sometimes a patient with a low platelet count requires concomitant antithrombotic treatment as well. In order to identify and treat the cause and the effects of the thrombocytopenia, you have to put together several pieces of information, solving a unique jig-jaw puzzle. The present work is not a textbook article about thrombocytopenia, rather a collection of differential diagnostic thoughts, treatment concepts, and some basic knowledge, that you can retrieve when facing your next thrombocytopenic patient. Enjoy reading it, but most importantly enjoy taking care of patients with a low platelet count. I bet the present work will assist you in this challenging and rewarding clinical task. © Schattauer 2013. Source


Schlunegger F.,University of Bern | Mosar J.,University of Fribourg
International Journal of Earth Sciences | Year: 2011

We present a synoptic overview of the Miocene-present development of the northern Alpine foreland basin (Molasse Basin), with special attention to the pattern of surface erosion and sediment discharge in the Alps. Erosion of the Molasse Basin started at the same time that the rivers originating in the Central Alps were deflected toward the Bresse Graben, which formed part of the European Cenozoic rift system. This change in the drainage direction decreased the distance to the marine base level by approximately 1,000km, which in turn decreased the average topographic elevation in the Molasse Basin by at least 200m. Isostatic adjustment to erosional unloading required ca. 1,000m of erosion to account for this inferred topographic lowering. A further inference is that the resulting increase in the sediment discharge at the Miocene-Pliocene boundary reflects the recycling of Molasse units. We consider that erosion of the Molasse Basin occurred in response to a shift in the drainage direction rather than because of a change in paleoclimate. Climate left an imprint on the Alpine landscape, but presumably not before the beginning of glaciation at the Pliocene-Pleistocene boundary. Similar to the northern Alpine foreland, we do not see a strong climatic fingerprint on the pattern or rates of exhumation of the External Massifs. In particular, the initiation and acceleration of imbrication and antiformal stacking of the foreland crust can be considered solely as a response to the convergence of Adria and Europe, irrespective of erosion rates. However, the recycling of the Molasse deposits since 5Ma and the associated reduction of the loads in the foreland could have activated basement thrusts beneath the Molasse Basin in order to restore a critical wedge. In conclusion, we see the need for a more careful consideration of both tectonic and climatic forcing on the development of the Alps and the adjacent Molasse Basin. © 2010 Springer-Verlag. Source


Spiliotis M.,University of Bern
PLoS ONE | Year: 2012

Inverse fusion PCR cloning (IFPC) is an easy, PCR based three-step cloning method that allows the seamless and directional insertion of PCR products into virtually all plasmids, this with a free choice of the insertion site. The PCR-derived inserts contain a vector-complementary 5′-end that allows a fusion with the vector by an overlap extension PCR, and the resulting amplified insert-vector fusions are then circularized by ligation prior transformation. A minimal amount of starting material is needed and experimental steps are reduced. Untreated circular plasmid, or alternatively bacteria containing the plasmid, can be used as templates for the insertion, and clean-up of the insert fragment is not urgently required. The whole cloning procedure can be performed within a minimal hands-on time and results in the generation of hundreds to ten-thousands of positive colonies, with a minimal background. © 2012 Markus Spiliotis. Source


Wulischleger C.W.,ETH Zurich | Gertsch J.,University of Bern | Altmann K.-H.,ETH Zurich
Organic Letters | Year: 2010

Chemical Equation Presentation The stereoselective synthesis of the monocyclic peloruside A analogue 4 has been achieved, following a new efficient approach for the introduction of the side chain, involving a late-stage addition of vinyl lithium species 7a to aldehyde 8. Further key steps are a highly diastereoselective allyltitanation reaction and a RCM-based macrocyclization. © 2010 American Chemical Society. Source


Borchard A.,Swiss Patient Safety Foundation | Schwappach D.L.B.,Swiss Patient Safety Foundation | Schwappach D.L.B.,University of Bern | Barbir A.,University of Zurich | Bezzola P.,Swiss Patient Safety Foundation
Annals of Surgery | Year: 2012

OBJECTIVE: A systematic literature review was conducted to assess the effectiveness of, compliance with, and critical factors for the implementation of safety checklists in surgery. BACKGROUND: With the aim of increasing patient safety, checklists have gained growing attention. Information about effectiveness, compliance, and critical factors for implementation is crucial for whether and which of the available instruments to use. DATA SOURCES: Medline including Premedline (OvidSP), Embase, and Cochrane Collaboration Library, hand search, a search of reference lists of key articles, and tables of content. STUDY SELECTION: Electronic databases returned 4997 citations, of which 84 articles were chosen for full-text review. Finally, 22 articles were included in this review. DATA EXTRACTION: Data relating to care setting, study methods and design, sample population, survey response rate, type of checklist, aim, effectiveness, compliance, attitudes, and critical factors were extracted from the studies. A random effects meta-analysis of effectiveness data was conducted if 2 or more studies reported a specified outcome. RESULTS: With the use of checklists, the relative risk for mortality is 0.57 [95% confidence interval (CI): 0.42-0.76] and for any complications 0.63 (95% CI: 0.58-0.67). The overall compliance rate ranged from 12% to 100% (mean: 75%) and for the Time Out from 70% to 100% (mean: 91%). CONCLUSIONS: Checklists are effective and economic tools that decrease mortality and morbidity. Compliance of surgical staff with checklists was good overall. Further research in particular relating to implementation is needed. Copyright © 2012 by Lippincott Williams & Wilkins. Source


Wagner J.T.,University of Bern
Swiss medical weekly | Year: 2011

In Switzerland, approximately 350,000 people aged 70 years or older own a valid driving license. By law, these drivers are medically assessed every other year, most commonly by their general practitioner, to exclude that a medical condition is interfering with their driving skills. A prerequisite for driving is the integration of high-level cognitive functions with perception and motor function. Ageing, per se, does not necessarily impair driving or increase the crash risk. However, medical conditions, such as cognitive impairment and dementia, become more prevalent with advancing age and may contribute to poor driving and an increased crash risk. The extent to which driving skills are impaired depends on the cause of dementia, disease severity, other co-morbidities and individual compensation strategies. Dementia often remains undiagnosed and therefore general practitioners (GPs) can find themselves in the difficult situation to disclose a suspicion about cognitive impairment and queries about medical fitness to drive, at the same time. In addition, the literature suggests that cognitive screening tests, most commonly used by GPs, have a limited role in judging whether an older person remains fit to drive. Further specialist assessment, for example in a memory clinic or on the road testing (ORT), may be helpful when the diagnosis or its implication for driving remain unclear. Here, we review the literature about cognition and driving, for GPs who advise older drivers who wish to continue driving. Source


Vidal R.,Johns Hopkins University | Favaro P.,University of Bern
Pattern Recognition Letters | Year: 2014

We consider the problem of fitting a union of subspaces to a collection of data points drawn from one or more subspaces and corrupted by noise and/or gross errors. We pose this problem as a non-convex optimization problem, where the goal is to decompose the corrupted data matrix as the sum of a clean and self-expressive dictionary plus a matrix of noise and/or gross errors. By self-expressive we mean a dictionary whose atoms can be expressed as linear combinations of themselves with low-rank coefficients. In the case of noisy data, our key contribution is to show that this non-convex matrix decomposition problem can be solved in closed form from the SVD of the noisy data matrix. The solution involves a novel polynomial thresholding operator on the singular values of the data matrix, which requires minimal shrinkage. For one subspace, a particular case of our framework leads to classical PCA, which requires no shrinkage. For multiple subspaces, the low-rank coefficients obtained by our framework can be used to construct a data affinity matrix from which the clustering of the data according to the subspaces can be obtained by spectral clustering. In the case of data corrupted by gross errors, we solve the problem using an alternating minimization approach, which combines our polynomial thresholding operator with the more traditional shrinkage-thresholding operator. Experiments on motion segmentation and face clustering show that our framework performs on par with state-of-the-art techniques at a reduced computational cost. © 2013 Elsevier B.V. All rights reserved. Source


Furholz M.,University of Bern
European journal of applied physiology | Year: 2013

The risk of sudden death is increased in athletes with a male predominance. Regular physical activity increases vagal tone, and may protect against exercise-induced ventricular arrhythmias. We investigated training-related modulations of the autonomic nervous system in female and male endurance athletes. Runners of a 10-mile race were invited. Of 873 applicants, 68 female and 70 male athletes were randomly selected and stratified according to their average weekly training hours in a low (≤4 h) and high (>4 h) volume training group. Analysis of heart rate variability was performed over 24 h. Spectral components (high frequency [HF] and low frequency [LF] power in normalized units) were analyzed for hourly 5 min segments and averaged for day- and nighttime. One hundred and fourteen athletes (50 % female, mean age 42 ± 7 years) were included. No significant gender difference was observed for training volume and 10-mile race time. Over the 24-h period, female athletes exhibited a higher HF and lower LF power for each hourly time-point. Female gender and endurance training hours were independent predictors of a higher HF and lower LF power. In female athletes, higher training hours were associated with a higher HF and lower LF power during nighttime. In male athletes, the same was true during daytime. In conclusion, female and male athletes showed a different circadian pattern of the training-related increase in markers of vagal tone. For a comparable amount of training volume, female athletes maintained their higher markers of vagal tone, possibly indicating a superior protection against exercise-induced ventricular arrhythmias. Source


Taborsky M.,University of Bern
Ethology | Year: 2014

Tinbergen's (1963, Z. Tierpsychol. 20, 410-433) four questions have guided the conceptual thinking of behavioural biologists over five decades. This is partly based on a misunderstanding of the aims and virtue of this article. Tinbergen called attention to the fact that his classification of problems is somehow illogical. Here, an attempt is made to remove some of the inconsistency by reformulating the levels of analysis of biological (including behavioural) traits. Furthermore, important merits of Tinbergen's milestone paper that have remained largely unnoticed are put in perspective. Perhaps the most lasting of several functions of that article has been its pivotal role in establishing a new research discipline, behavioural ecology. © 2014 Blackwell Verlag GmbH. Source


Bassetti C.L.,University of Bern
Handbook of Clinical Neurology | Year: 2014

Syncope describes a sudden and brief transient loss of consciousness (TLOC) with postural failure due to cerebral global hypoperfusion. The term TLOC is used when the cause is either unrelated to cerebral hypoperfusion or is unknown.The most common causes of syncopal TLOC include: (1) cardiogenic syncope (cardiac arrhythmias, structural cardiac diseases, others); (2) orthostatic hypotension (due to drugs, hypovolemia, primary or secondary autonomic failure, others); (3) neurally mediated syncope (cardioinhibitory, vasodepressor, and mixed forms). Rarely neurologic disorders (such as epilepsy, transient ischemic attacks, and the subclavian steal syndrome) can lead to cerebal hypoperfusion and syncope.Nonsyncopal TLOC may be due to neurologic (epilepsy, sleep attacks, and other states with fluctuating vigilance), medical (hypoglycemia, drugs), psychiatric, or post-traumatic disorders.Basic diagnostic workup of TLOC includes a thorough history and physical examination, and a 12-lead electrocardiogram (ECG). Blood testing, electroencephalogram (EEG), magnetic resonance imaging (MRI) of the brain, echocardiography, head-up tilt test, carotid sinus massage, Holter monitoring, and loop recorders should be obtained only in specific contexts. Management strategies involve pharmacologic and nonpharmacologic interventions, and cardiac pacing. © 2014 Elsevier B.V. Source


Groothuis T.G.G.,Groningen Institute for Evolutionary Life science | Taborsky B.,University of Bern
Frontiers in Zoology | Year: 2015

There is increasing attention for integrating mechanistic and functional approaches to the study of (behavioural) development. As environments are mostly unstable, it is now often assumed that genetic parental information is in many cases not sufficient for offspring to become optimally adapted to the environment and that early environmental cues, either indirectly via the parents or from direct experience, are necessary to prepare them for a specific environment later in life. To study whether these early developmental processes are adaptive and through which mechanism, not only the early environmental cues but also how they impinge on the later-life environmental context has therefore to be taken into account when measuring the animal's performance. We first discuss at the conceptual level six ways in which interactions between influences of different time windows during development may act (consolidation, cumulative information gathering and priming, compensation, buffering, matching and mismatching, context dependent trait expression). In addition we discuss how different environmental factors during the same time window may interact in shaping the phenotype during development. Next we discuss the pros and cons of several experimental designs for testing these interaction effects, highlighting the necessity for full, reciprocal designs and the importance of adjusting the nature and time of manipulation to the animal's adaptive capacity. We then review support for the interaction effects from both theoretical models and animal experiments in different taxa. This demonstrates indeed the existence of interactions at multiple levels, including different environmental factors, different time windows and between generations. As a consequence, development is a life-long, environment-dependent process and therefore manipulating only the early environment without taking interaction effects with other and later environmental influences into account may lead to wrong conclusions and may also explain inconsistent results in the literature. © 2015 Groothuis and Taborsky. Source


Ereditato A.,University of Bern
Nuclear Physics B | Year: 2016

Almost 20 years after the first conceptual design of the experiment, five years of running in the Gran Sasso underground laboratory (LNGS), and billions of billions muon-neutrinos sent from CERN along the CNGS beam, in 2015 the OPERA neutrino detector has allowed the long-awaited discovery of the direct transformation (oscillation) of muon-neutrinos into tau-neutrinos. This result unambiguously confirms the interpretation of the so-called atmospheric channel, after the discovery of neutrino oscillations by the Super-Kamiokande Collaboration in 1998. © 2016 The Author. Source


Overview: Regardless of whether a pathogen is viral, bacterial, parasitic, fungal or an emerging unknown, the mainstay of infectious disease control is hygiene, and the cornerstone of good hygiene is effective disinfection. Challenges and current choices: Certain pathogens present a challenge to kill effectively: parvovirus, protozoal oocysts, mycobacteria, bacterial spores and prions resist most disinfectants but can be eliminated through heat, especially steam, which will kill protozoal oocysts. Heat is the safest and most effective disinfectant, but cannot be universally applied. Temperatures in washing machines and dishwashers should be at least 60°C to eliminate pathogenic spores and resistant viruses. Enveloped viruses are susceptible to most disinfectants; of the non-enveloped viruses, parvovirus is recognised as being the most difficult to eradicate. Sodium hypochlorite is recommended for many applications: cleaning of floors, laundry, food preparation surfaces and utensils. Skin scrubs and rubs containing alcohols are more effective than those containing chlorhexidine, and less subject to contamination. Disinfectants to avoid: Deficiency of the enzyme UDP-glucuronosyl transferase renders the cat susceptible to the toxic effects of phenol-based disinfectants (including many essential oils), so these should be avoided in feline environments. Quaternary ammonium compounds (eg, benzalkonium chloride) are also probably best avoided. The future: Veterinary disinfection approaches in the future may include use of ultraviolet radiation and, increasingly, silver. © 2015, © Published by SAGE on behalf of ISFM and AAFP 2015. Source


Kaufmann T.,University of Bern | Strasser A.,Walter and Eliza Hall Institute of Medical Research | Strasser A.,University of Melbourne | Jost P.J.,TU Munich
Cell Death and Differentiation | Year: 2012

Fas (also called CD95 or APO-1), a member of a subgroup of the tumour necrosis factor receptor superfamily that contain an intracellular death domain, can initiate apoptosis signalling and has a critical role in the regulation of the immune system. Fas-induced apoptosis requires recruitment and activation of the initiator caspase, caspase-8 (in humans also caspase-10), within the death-inducing signalling complex. In so-called type 1 cells, proteolytic activation of effector caspases (-3 and-7) by caspase-8 suffices for efficient apoptosis induction. In so-called type 2 cells, however, killing requires amplification of the caspase cascade. This can be achieved through caspase-8-mediated proteolytic activation of the pro-apoptotic Bcl-2 homology domain (BH)3-only protein BH3-interacting domain death agonist (Bid), which then causes mitochondrial outer membrane permeabilisation. This in turn leads to mitochondrial release of apoptogenic proteins, such as cytochrome c and, pertinent for Fas death receptor (DR)-induced apoptosis, Smac/DIABLO (second mitochondria-derived activator of caspase/direct IAP binding protein with low Pi), an antagonist of X-linked inhibitor of apoptosis (XIAP), which imposes a brake on effector caspases. In this review, written in honour of Juerg Tschopp who contributed so much to research on cell death and immunology, we discuss the functions of Bid and XIAP in the control of Fas DR-induced apoptosis signalling, and we speculate on how this knowledge could be exploited to develop novel regimes for treatment of cancer. © 2012 Macmillan Publishers Limited All rights reserved. Source


Bedi A.,University of Michigan | Dolan M.,Hospital for Special Surgery | Leunig M.,University of Bern | Kelly B.T.,Hospital for Special Surgery
Arthroscopy - Journal of Arthroscopic and Related Surgery | Year: 2011

Mechanical hip pain typically has been associated either with dynamic factors resulting in abnormal stress and contact between the femoral head and acetabular rim when the hip is in motion or with static overload stresses related to insufficient congruency between the head and acetabular socket in the axially loaded (standing) position. Compensatory motion may adversely affect the dynamic muscle forces in the pelvic region, leading to further strain and pain. Hip pain related to static overload stresses may also be localized to the anteromedial groin, but compensatory dysfunction of the periarticular musculature may lead to muscular fatigue and associated pain throughout the hip. As our understanding of hip joint mechanics has advanced, it has become increasingly apparent that hip pain in the absence of osteoarthritis may be due to a complex combination of mechanical stresses, both dynamic and static. With an emphasis on findings in the recent literature, this review will describe the dynamic and static factors associated with mechanical hip pain, the combinations of dynamic and static stresses that are commonly identified in hip pain, and common patterns of compensatory injury in patients with femoroacetabular impingement. © 2011 Arthroscopy Association of North America. Source


Heng K.,University of Bern | Malik M.,ETH Zurich
Monthly Notices of the Royal Astronomical Society | Year: 2013

Motivated by the reported dearth of debris discs around M stars, we use survival models to study the occurrence of planetesimal discs around them. These survival models describe a planetesimal disc with a small number of parameters, determine if it may survive a series of dynamical processes and compute the associated infrared excess. For the Wide-field Infrared Survey Explorer (WISE) satellite, we demonstrate that the dearth of debris discs aroundMstars may be attributed to the small semimajor axes generally probed if either: (1) the dust grains behave like blackbodies emitting at a peak wavelength coincident with the observed one; (2) or the grains are hotter than predicted by their blackbody temperatures and emit at peak wavelengths that are shorter than the observed one. At these small distances from the M star, planetesimals are unlikely to survive or persist for time-scales of 300 Myr or longer if the disc is too massive. Conversely, our survival models allow for the existence of a large population of low-mass debris discs that are too faint to be detected with current instruments.We gain further confidence in our interpretation by demonstrating the ability to compute infrared excesses for Sun-like stars that are broadly consistent with reported values in the literature. However, our interpretation becomes less clear and large infrared excesses are allowed if only one of these scenarios holds: (3) the dust grains are hotter than blackbody and predominantly emit at the observed wavelength; (4) or are blackbody in nature and emit at peak wavelengths longer than the observed one. Both scenarios imply that the parent planetesimals reside at larger distances from the star than inferred if the dust grains behaved like blackbodies. In all scenarios, we show that the infrared excesses detected at 22 μm (via WISE) and 70 μm (via Spitzer) from AU Mic are easily reconciled with its young age (12 Myr). Conversely, the existence of the old debris disc (2-8 Gyr) from GJ 581 is due to the large semimajor axes probed by the Herschel PACS instrument.We elucidate the conditions under which stellar wind drag may be neglected when considering dust populations around M stars. The WISE satellite should be capable of detecting debris discs around young M stars with ages ~10 Myr. © 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. Source


Genitsch V.,University of Bern
Prostate Cancer and Prostatic Diseases | Year: 2016

Background:MUC1 is a membrane-bound glycoprotein that belongs to the mucin family. It is involved in cell adhesion and intracellular signaling. Aberrant expression of MUC1 has been observed in different carcinomas, including prostate cancer, where it may serve as a therapeutic target. There are no data on the prognostic value of MUC1 in metastatic prostate cancer.Methods:MUC1 expression was evaluated in tissue microarrays constructed from 119 nodal positive prostate cancer patients treated by radical prostatectomy and extended lymphadenectomy. MUC1 status was correlated with various tumor features and biochemical recurrence-free (bRFS), disease-specific survival (DSS) and overall survival (OS).Results:MUC1 expression was significantly different between primary tumors, lymph node metastases and non-neoplastic glands (scores 53.7 vs 30.1 vs 16.6; P<0.0001). High MUC1 expression in primary tumors was positively correlated with tumor volume (mean 24.4 cm3 vs 14.5 cm3; P=0.005) and T-stage (P=0.009); in lymph node metastases, high expression corresponded with a greater total size of metastases (mean 35.8 mm vs 12.7 mm; P<0.001) and a higher ratio of positive to examined lymph nodes (mean 0.22 vs 0.12; P=0.014). High MUC1 expression in lymph node metastases predicted unfavorable outcomes compared with low MUC1 expression (bRFS P=0.023, DSS and OS P⩽0.001), whereas in primary tumors, the same tendency was non-significant. In multivariate analyses, high MUC1 expression in primary tumors and lymph node metastases independently predicted early biochemical failure (P=0.046) and tumor-related death (P=0.0038), respectively.Conclusions:High MUC1 in either primary tumor or lymph node metastases correlates significantly with unfavorable tumor features and survival. Overexpression of MUC1 in the metastases of a subset of prostate cancer patients may have therapeutic potential.Prostate Cancer and Prostatic Diseases advance online publication, 10 May 2016; doi:10.1038/pcan.2016.11. © 2016 Macmillan Publishers Limited Source


Zwahlen M.,University of Bern
Swiss medical weekly : official journal of the Swiss Society of Infectious Diseases, the Swiss Society of Internal Medicine, the Swiss Society of Pneumology | Year: 2010

Screening people without symptoms of disease is an attractive idea. Screening allows early detection of disease or elevated risk of disease, and has the potential for improved treatment and reduction of mortality. The list of future screening opportunities is set to grow because of the refinement of screening techniques, the increasing frequency of degenerative and chronic diseases, and the steadily growing body of evidence on genetic predispositions for various diseases. But how should we decide on the diseases for which screening should be done and on recommendations for how it should be implemented? We use the examples of prostate cancer and genetic screening to show the importance of considering screening as an ongoing population-based intervention with beneficial and harmful effects, and not simply the use of a test. Assessing whether screening should be recommended and implemented for any named disease is therefore a multi-dimensional task in health technology assessment. There are several countries that already use established processes and criteria to assess the appropriateness of screening. We argue that the Swiss healthcare system needs a nationwide screening commission mandated to conduct appropriate evidence-based evaluation of the impact of proposed screening interventions, to issue evidence-based recommendations, and to monitor the performance of screening programmes introduced. Without explicit processes there is a danger that beneficial screening programmes could be neglected and that ineffective, and potentially harmful, screening procedures could be introduced. Source


Paracetamol (acetaminophen, APAP) is a universally used analgesic and antipyretic agent. Considered safe at therapeutic doses, overdoses cause acute liver damage characterized by centrilobular hepatic necrosis. One of the major clinical problems of paracetamol-induced liver disease is the development of hemorrhagic alterations. Although hepatocytes represent the main target of the cytotoxic effect of paracetamol overdose, perturbations within the endothelium involving morphological changes of liver sinusoidal endothelial cells (LSECs) have also been described in paracetamol-induced liver disease. Recently, we have shown that paracetamol-induced liver damage is synergistically enhanced by the TRAIL signaling pathway. As LSECs are constantly exposed to activated immune cells expressing death ligands, including TRAIL, we investigated the effect of TRAIL on paracetamol-induced LSEC death. We here demonstrate for the first time that TRAIL strongly enhances paracetamol-mediated LSEC death with typical features of apoptosis. Inhibition of caspases using specific inhibitors resulted in a strong reduction of cell death. TRAIL appears to enhance paracetamol-induced LSEC death via the activation of the pro-apoptotic BH3-only proteins Bid and Bim, which initiate the mitochondrial apoptotic pathway. Taken together this study shows that the liver endothelial layer, mainly LSECs, represent a direct target of the cytotoxic effect of paracetamol and that activation of TRAIL receptor synergistically enhances paracetamol-induced LSEC death via the mitochondrial apoptotic pathway. TRAIL-mediated acceleration of paracetamol-induced cell death may thus contribute to the pathogenesis of paracetamol-induced liver damage. Source


Becher T.,University of Bern | Neubert M.,Johannes Gutenberg University Mainz | Wilhelm D.,Johannes Gutenberg University Mainz
Journal of High Energy Physics | Year: 2013

Using methods from effective field theory, we have recently developed a novel, systematic framework for the calculation of the cross sections for electroweak gauge-boson production at small and very small transverse momentum q T, in which large logarithms of the scale ratio m V /q T are resummed to all orders. This formalism is applied to the production of Higgs bosons in gluon fusion at the LHC. The production cross section receives logarithmically enhanced corrections from two sources: the running of the hard matching coefficient and the collinear factorization anomaly. The anomaly leads to the dynamical generation of a non-perturbative scale q* ∼ mH e-const/αs(m H) ≈ 8GeV, which protects the process from receiving large long-distance hadronic contributions. We present numerical predictions for the transverse-momentum spectrum of Higgs bosons produced at the LHC, finding that it is quite insensitive to hadronic effects. © 2013 SISSA, Trieste, Italy. Source


For centuries the science of pharmacognosy has dominated rational drug development until it was gradually substituted by target-based drug discovery in the last fifty years. Pharmacognosy stems from the different systems of traditional herbal medicine and its reverse pharmacology approach has led to the discovery of numerous pharmacologically active molecules and drug leads for humankind. But do botanical drugs also provide effective mixtures? Nature has evolved distinct strategies to modulate biological processes, either by selectively targeting biological macromolecules or by creating molecular promiscuity or polypharmacology (one molecule binds to different targets). Widely claimed to be superior over monosubstances, mixtures of bioactive compounds in botanical drugs allegedly exert synergistic therapeutic effects. Despite evolutionary clues to molecular synergism in nature, sound experimental data are still widely lacking to support this assumption. In this short review, the emerging concept of network pharmacology is highlighted, and the importance of studying ligand-target networks for botanical drugs is emphasized. Furthermore, problems associated with studying mixtures of molecules with distinctly different pharmacodynamic properties are addressed. It is concluded that a better understanding of the polypharmacology and potential network pharmacology of botanical drugs is fundamental in the ongoing rationalization of phytotherapy. © Georg Thieme Verlag KG Stuttgart - New York. Source


Cotton is a leading agricultural non-food commodity associated with soil degradation, water pollution and pesticide poisoning due to high levels of agrochemical inputs. Organic farming is often promoted as a means of addressing the economic, environmental and health risks of conventional cotton production, and it is slowly gaining ground in the global cotton market. Organic and fair trade cotton are widely seen as opportunities for smallholder farmers to improve their livelihoods thanks to higher returns, lower input costs and fewer risks. Despite an increasing number of studies comparing the profitability of organic and non-organic farming systems in developing and industrialized countries, little has been published on organic farming in Central Asia. The aim of this article is to describe the economic performance and perceived social and environmental impacts of organic cotton in southern Kyrgyzstan, drawing on a comparative field study conducted by the author in 2009. In addition to economic and environmental aspects, the study investigated farmers' motivations toward and assessment of conversion to organic farming. Cotton yields on organic farms were found to be 10% lower, while input costs per unit were 42% lower; as a result, organic farmers' cotton revenues were 20% higher. Due to lower input costs as well as organic and fair trade price premiums, the average gross margin from organic cotton was 27% higher. In addition to direct economic benefits, organic farmers enjoy other benefits, such as easy access to credit on favorable terms, provision of uncontaminated cottonseed cooking oil and cottonseed cake as animal feed, and marketing support as well as extension and training services provided by newly established organic service providers. The majority of organic farmers perceive improved soil quality, improved health conditions, and positively assess their initial decision to convert to organic farming. The major disadvantage of organic farming is the high manual labor input required. In the study area, where manual farm work is mainly women's work and male labor migration is widespread, women are most affected by this negative aspect of organic farming. Altogether, the results suggest that, despite the inconvenience of a higher workload, the advantages of organic farming outweigh its disadvantages and that conversion to organic farming improves the livelihoods of small-scale farmers. © Copyright Cambridge University Press 2011. Source


Simon D.,University of Bern | Wardlaw A.,University of Leicester | Rothenberg M.E.,Cincinnati Childrens Hospital Medical Center
Journal of Allergy and Clinical Immunology | Year: 2010

Eosinophils are multifunctional leukocytes that increase in various tissues in patients with a variety of disorders. Locally, they can be involved in the initiation and propagation of diverse inflammatory responses. In this review the clinical association of eosinophils with diseases of the skin, lung, and gastrointestinal tract is summarized. An approach to determining the causal role of eosinophils in these diseases is presented. Recent findings concerning molecular diagnosis, cause, and treatment are discussed. © 2010 American Academy of Allergy, Asthma & Immunology. Source


Marionneau C.,University of Nantes | Abriel H.,University of Bern
Journal of Molecular and Cellular Cardiology | Year: 2015

The cardiac voltage-gated Na+ channel, NaV1.5, is responsible for the upstroke of the action potential in cardiomyocytes and for efficient propagation of the electrical impulse in the myocardium. Even subtle alterations of NaV1.5 function, as caused by mutations in its gene SCN5A, may lead to many different arrhythmic phenotypes in carrier patients. In addition, acquired malfunctions of NaV1.5 that are secondary to cardiac disorders such as heart failure and cardiomyopathies, may also play significant roles in arrhythmogenesis. While it is clear that the regulation of NaV1.5 protein expression and function tightly depends on genetic mechanisms, recent studies have demonstrated that NaV1.5 is the target of various post-translational modifications that are pivotal not only in physiological conditions, but also in disease. In this review, we examine the recent literature demonstrating glycosylation, phosphorylation by Protein Kinases A and C, Ca2+/Calmodulin-dependent protein Kinase II, Phosphatidylinositol 3-Kinase, Serum- and Glucocorticoid-inducible Kinases, Fyn and Adenosine Monophosphate-activated Protein Kinase, methylation, acetylation, redox modifications, and ubiquitylation of NaV1.5. Modern and sensitive mass spectrometry approaches, applied directly to channel proteins that were purified from native cardiac tissues, have enabled the determination of the precise location of post-translational modification sites, thus providing essential information for understanding the mechanistic details of these regulations. The current challenge is first, to understand the roles of these modifications on the expression and the function of NaV1.5, and second, to further identify other chemical modifications. It is postulated that the diversity of phenotypes observed with NaV1.5-dependent disorders may partially arise from the complex post-translational modifications of channel protein components. © 2015 Elsevier Ltd. Source


Childhood stroke is increasingly being recognized as an important burden not only for affected children and families, but also for socioeconomic reasons. A primary problem is delayed diagnosis, due to the many mimics of childhood stroke, and the variety of manifesting symptoms. The most important is hemiparesis (with/without dysphasia or facial palsy), but ataxia, seizures, and many more are also possible. Suspicion of stroke has to be ascertained by neuroimaging, gold standard being (diffusion weighted) magnetic resonance. Risk factors are multiple, but their presence might help to increase the suspicion of stroke. The most important factors are infectious/parainfectious etiologies, frequently possibly manifesting by transient focal cerebral arteriopathy (FCA). Cardiological underlying problems are the second most important. Arteriopathies can be detected in about half of the children, besides FCA and dissection and MoyaMoya disease are the most important. Hereditary coagulopathies increase the risk of stroke. There is still a controversy on best treatment in children: platelet antiaggregation and heparinization are used about equally. Thrombolysis is being discussed increasingly. Severity of symptoms at manifestation and on follow-up are not less significant in children than in young adults. About two-third of the children have significant residual neurological problems and a majority cognitive and behavior problems. Copyright © 2012 by Thieme Medical Publishers, Inc. Source


Djonov V.,University of Bern
Journal of Mammary Gland Biology and Neoplasia | Year: 2010

Concomitant with the extensive growth and differentiation of the mammary epithelium during pregnancy and lactation, and epithelial involution after weaning, the vasculature of the mammary gland undergoes repeated cycles of expansion and regression. Vascular expansion is effected by sprouting angiogenesis, intussusception and conceivably also vasculogenesis. The capacity of the epithelial cells to stimulate vascular growth and differentiation is dependent on the constellation of systemic and local hormones and growth factors as well as the changing demands for oxygenation and nutrient supply. This results in the release of angiogenic factors which stimulate endothelial cell growth and regulate vascular architecture. In contrast to the angiogenic phase of the mammary gland cycle, little is known about the control of vascular regression although this would possibly offer new insights into therapeutic possibilities against breast cancer. In this review we summarize knowledge regarding the mechanisms regulating the vasculature of the mammary gland and delineate the importance of the vasculature in the attainment of organ function. In addition, we discuss the angiogenic mechanisms observed during mammary carcinogenesis and their consequences for breast cancer therapy. © 2010 Springer Science+Business Media, LLC. Source


Richter M.,University of Bern | Moor I.,Bielefeld University | van Lenthe F.J.,Erasmus University Rotterdam
Journal of Epidemiology and Community Health | Year: 2012

Background Efforts to explain social inequalities in health have mainly focused on adults. Few studies have systematically analysed different explanatory pathways in adolescence. This study is among the first to examine the contribution of material, psychosocial and behavioural factors in the explanation of inequalities in adolescent health. Methods Data were obtained from the German part of the cross-sectional 'Health Behaviour in School-aged Children' Survey in 2006, with a total of 6997 respondents aged 11-15 years (response rate 86%). Socioeconomic position was measured using the Family Affluence Scale. Multistage logistic regression models were used to assess the relative importance of explanatory factors. Results Compared with adolescents from high affluent backgrounds, the ORs of fair/poor self-rated health increased to 1.53 (95% CI 1.11 to 2.12) in low affluent boys and to 2.08 (95% CI 1.62 to 2.67) in low affluent girls. In the separate analyses, material, psychosocial and behavioural factors attenuated the OR by 30-50%. Together, the three explanatory factors reduced the OR by about 80% in low affluent boys and girls. The combined analyses illustrated that material factors contributed most to the differences in self-rated health because of their direct and indirect effect (through psychosocial and behavioural factors). Conclusions The findings show that the main explanatory approaches for adults also apply to adolescents. The direct and indirect contribution of material factors for inequalities in self-rated health was stronger than that of behavioural and psychosocial factors. Strategies for reducing health inequalities should primarily focus on improving material circumstances in lower affluent groups. Source


Fleming L.,Imperial College London | Wilson N.,Royal Brompton Hospital | Regamey N.,University of Bern | Bush A.,Imperial College London
Thorax | Year: 2012

Background: Previous studies in adults with asthma incorporating the control of sputum eosinophils into management strategies have shown significant reductions in exacerbations. A study was undertaken to investigate whether this strategy would be successful in children with severe asthma. Methods: 55 children (7-17 years) with severe asthma were randomised to either a conventional symptom-based management strategy or to an inflammation-based strategy (principally sputum eosinophils). Children were seen 3-monthly over a 1-year period. Results The annual rate of total and major exacerbations (courses of oral corticosteroids) was non-significantly lower in the inflammatory management group compared with the symptom management group (3.6 vs 4.8, incident rate ratio (IRR) 0.75, 95% CI 0.54 to 1.04, p=0.082; and 1.9 vs 2.7 IRR 0.73, 95% CI 0.42 to 1.28, p=0.274 for total and major exacerbations, respectively). Significantly fewer subjects in the inflammatory management group experienced an exacerbation within 28 days of a study visit. There were small non-significant differences in measures of asthma control (symptom-free days and short-acting β agonist use) favouring the inflammatory management group. There was no significant difference in the inhaled corticosteroid dose prescribed over the course of the study. Conclusion: Incorporating the control of sputum eosinophils into the management algorithm did not significantly reduce overall exacerbations or improve asthma control. Exacerbations were reduced in the short term, suggesting that more frequent measurements would be needed for a clinically useful effect and that controlling inflammation may have a role to play in subgroups of children with severe asthma. Source


Hering J.G.,Eawag - Swiss Federal Institute of Aquatic Science and Technology | Hering J.G.,ETH Zurich | Hering J.G.,Ecole Polytechnique Federale de Lausanne | Ingold K.M.,Eawag - Swiss Federal Institute of Aquatic Science and Technology | Ingold K.M.,University of Bern
Science | Year: 2012

Appropriately bounded integration can be a basis for sustainable management of water resources. Source


Zust T.,Cornell University | Agrawal A.A.,University of Bern
Nature Plants | Year: 2016

Aphids are important herbivores of both wild and cultivated plants. Plants rely on unique mechanisms of recognition, signalling and defence to cope with the specialized mode of phloem feeding by aphids. Aspects of the molecular mechanisms underlying aphid-plant interactions are beginning to be understood. Recent advances include the identification of aphid salivary proteins involved in host plant manipulation, and plant receptors involved in aphid recognition. However, a complete picture of aphid-plant interactions requires consideration of the ecological outcome of these mechanisms in nature, and the evolutionary processes that shaped them. Here we identify general patterns of resistance, with a special focus on recognition, phytohormonal signalling, secondary metabolites and induction of plant resistance. We discuss how host specialization can enable aphids to co-opt both the phytohormonal responses and defensive compounds of plants for their own benefit at a local scale. In response, systemically induced resistance in plants is common and often involves targeted responses to specific aphid species or even genotypes. As co-evolutionary adaptation between plants and aphids is ongoing, the stealthy nature of aphid feeding makes both the mechanisms and outcomes of these interactions highly distinct from those of other herbivore-plant interactions. © 2016 Macmillan Publishers Limited. Source


Laurent-Lucchetti J.,University of Bern | Santugini M.,HEC Montreal
Journal of Environmental Economics and Management | Year: 2012

It has long been recognized that the quality of property rights greatly impacts the economic development of a country and the use of its natural resources. Since Long [13], the conventional wisdom has been that ownership risk induces a firm to overuse the stock of a resource. However, the empirical evidence is mixed. In particular, Bohn and Deacon [1] find that weak property rights have an ambiguous effect on present extraction. We provide a theoretical model supporting these mixed observations in a common-pool resource environment. We show that if ownership risk includes a risk of expropriation in which the identities of the excluded firms are unknown ex ante, then the present extraction of all firms may decrease along with a higher risk of expropriation. The elasticity of demand for the resource is key in explaining the effect of ownership risk on present extraction. © 2011 Elsevier Inc. Source


Barentsz J.O.,Radboud UMC | Thoeny H.C.,University of Bern
Nature Reviews Urology | Year: 2015

Most metastatic lymph nodes in patients with prostate cancer go undetected by current imaging techniques and limited pelvic lymph node dissection (PLND), as they are small and located in difficult-to-reach areas. As the only current alternative is an extended PLND, the search for more accurate imaging techniques continues. © 2015 Macmillan Publishers Limited. All rights reserved. Source


Lopez-Terrada D.,Baylor College of Medicine | Zimmermann A.,University of Bern
Pediatric Blood and Cancer | Year: 2012

Systematic histopathologic examination of hepatoblastoma specimens from patients enrolled in therapeutic protocols has allowed the identification of clinically relevant histologic subtypes that are being incorporated into risk stratification systems. Genetic and molecular studies have documented recurrent chromosomal abnormalities and aberrant activation of developmental, and oncogenic signaling pathways in hepatoblastoma. Molecular profiling has also identified molecular subclasses and gene signatures that could be used to stratify hepatoblastoma patients. Future international collaboration is needed to develop consensus pathology classifications, and to progressively incorporate genetic and molecular biomarkers into therapeutic pediatric liver tumors protocols. © 2012 Wiley Periodicals, Inc. Source


Fuster D.G.,University of Bern | Alexander R.T.,University of Alberta
Pflugers Archiv European Journal of Physiology | Year: 2014

The SLC9 gene family encodes Na+/H+ exchangers (NHEs). These transmembrane proteins transport ions across lipid bilayers in a diverse array of species from prokaryotes to eukaryotes, including plants, fungi, and animals. They utilize the electrochemical gradient of one ion to transport another ion against its electrochemical gradient. Currently, 13 evolutionarily conserved NHE isoforms are known in mammals [22, 46, 128]. The SLC9 gene family (solute carrier classification of transporters: www.bioparadigms.org) is divided into three subgroups [46]. The SLC9A subgroup encompasses plasmalemmal isoforms NHE1-5 (SLC9A1-5) and the predominantly intracellular isoforms NHE6-9 (SLC9A6-9). The SLC9B subgroup consists of two recently cloned isoforms, NHA1 and NHA2 (SLC9B1 and SLC9B2, respectively). The SLC9C subgroup consist of a sperm specific plasmalemmal NHE (SLC9C1) and a putative NHE, SLC9C2, for which there is currently no functional data [46]. NHEs participate in the regulation of cytosolic and organellar pH as well as cell volume. In the intestine and kidney, NHEs are critical for transepithelial movement of Na+ and HCO3 - and thus for whole body volume and acid-base homeostasis [46]. Mutations in the NHE6 or NHE9 genes cause neurological disease in humans and are currently the only NHEs directly linked to human disease. However, it is becoming increasingly apparent that members of this gene family contribute to the pathophysiology of multiple human diseases. © 2013 Springer-Verlag Berlin Heidelberg. Source


Insitu observation of anion adsorption on industrial high-surface-area catalysts is used for the first time under oxygen reduction reaction (ORR) conditions with a defined mass transport. For this purpose, a specially fabricated electrode is used for which the catalyst layer is spray-coated on top of a structured Au contact layer and applied to our recently developed insitu attenuated total reflectance FTIR wall-jet electrode. The designed interface allows us to track anion adsorption and measure the reaction rate simultaneously under mass controlled conditions. The observed absorption bands are caused by anion interaction with the active phase and also the carbon support. If we analyze the absorption band intensity of adsorbed anions as a function of the oxygen reduction reaction rate, the band intensity decreases with the onset of the ORR. This shows that ORR inhibition is a complex interplay between site blocking caused by anion adsorption and oxide formation. Seeing is believing: Insitu FTIR spectroscopy observation of anion adsorption on industrial high-surface-area catalysts is used for the first time under oxygen reduction reaction conditions with a defined mass transport. © 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim. Source


Seiler C.,University of Bern
European Journal of Clinical Investigation | Year: 2010

Background Coronary collaterals are an alternative source of blood supply to myocardium jeopardized by ischaemia. Well-developed coronary collateral arteries in patients with coronary artery disease (CAD) mitigate myocardial infarcts and improve survival. Methods and results Collateral arteries preventing myocardial ischaemia during brief vascular occlusion are present in 1/3 of patients with CAD. Among individuals without relevant coronary stenoses, there are preformed collateral arteries preventing myocardial ischaemia in 20-25%. Collateral flow sufficient to prevent myocardial ischaemia during coronary occlusion amounts to ‡25% of the normal flow through the open vessel. Myocardial infarct size, the most important prognostic determinant after such an event, is the product of coronary artery occlusion time, area at risk for infarction and the inverse of collateral supply. Coronary collateral flow can be assessed only during vascular occlusion of the collateral-receiving artery. The gold standard for coronary collateral assessment is the measurement of intracoronary occlusive pressure- or velocity-derived collateral flow index expressing collateral as a fraction of flow during vessel patency. Approximately one of five patients with CAD cannot be revascularized by percutaneous coronary intervention or coronary artery bypass grafting. Therapeutic promotion of collateral growth is a valuable treatment strategy in those patients. Conclusions Promotion of collateral growth should aim at inducing the development of large conductive collateral arteries (i.e. arteriogenesis) and not so much the sprouting of capillary like vessels (i.e. angiogenesis). Large conductive collateral arteries appear to be effectively promoted via the activation of monocytes/macrophages by means of granulocyte-colony stimulating factor or of augmenting coronary flow velocity. © 2010 Stichting European Society for Clinical Investigation Journal Foundation. Source


Muhlemann O.,University of Bern | Lykke-Andersen J.,University of California at San Diego
RNA Biology | Year: 2010

The nonsense-mediated mRNA decay (NMD) pathway is responsible for the rapid degradation of eukaryotic mRNAs on which ribosomes fail to terminate translation properly. NMD thereby contributes to the elimination of aberrant mRNAs, improving the fidelity of gene expression, but also serves to regulate gene expression at the posttranscriptional level. Here we discuss recent evidence as to how and where mRNAs targeted to NMD are degraded in human cells. We discuss accumulating evidence that the decay step of human NMD can be initiated by two different mechanisms: either by SMG6-mediated endonucleolytic cleavage near the aberrant stop codon, or by deadenylation and decapping. While there is evidence that mRNAs targeted for NMD have the capacity to accumulate with other translationally repressed mRNAs in P-bodies, there is currently no evidence that this is required for the degradation of the NMD substrate. It therefore remains an open question whether NMD in human cells is restricted to a particular cellular location or whether it can be initiated wherever translation of the NMD substrate takes place. © 2010 Landes Bioscience. Source


Engelhardt B.,University of Bern
Journal of Cerebral Blood Flow and Metabolism | Year: 2011

Brain microvascular endothelium forms an active permeability barrier, the blood-brain barrier (BBB). In neurologic disorders, barrier properties of the BBB are often lost indicating their dependance on molecular cues of the brain microenvironment. In this issue, Osada et al demonstrate that the endothelial extracellular matrix (ECM) provides one of these cues. Their study shows that Β1-integrin-mediated adhesion of brain endothelial cells to the surrounding ECM is critical for stabilizing claudin-5 in BBB tight junctions (TJs) and BBB integrity. These observations point to a novel intracellular signaling pathway from Β1-integrin/ECM endothelial adhesions to BBB TJs contributing to BBB integrity. © 2011 ISCBFM All rights reserved. Source


Thamrin C.,University of Bern
Paediatric respiratory reviews | Year: 2010

There is increasing interest in the study of fractals in medicine. In this review, we provide an overview of fractals, of techniques available to describe fractals in physiological data, and we propose some reasons why a physician might benefit from an understanding of fractals and fractal analysis, with an emphasis on paediatric respiratory medicine where possible. Among these reasons are the ubiquity of fractal organisation in nature and in the body, and how changes in this organisation over the lifespan provide insight into development and senescence. Fractal properties have also been shown to be altered in disease and even to predict the risk of worsening of disease. Finally, implications of a fractal organisation include robustness to errors during development, ability to adapt to surroundings, and the restoration of such organisation as targets for intervention and treatment. Copyright 2010 Elsevier Ltd. All rights reserved. Source


Hajicek P.,University of Bern
Foundations of Physics | Year: 2011

A modified Beltrametti-Cassinelli-Lahti model of the measurement apparatus that satisfies both the probability reproducibility condition and the objectification requirement is constructed. Only measurements on microsystems are considered. The cluster separability forms a basis for the first working hypothesis: the current version of quantum mechanics leaves open what happens to systems when they change their separation status. New rules that close this gap can therefore be added without disturbing the logic of quantum mechanics. The second working hypothesis is that registration apparatuses for microsystems must contain detectors and that their readings are signals from detectors. This implies that the separation status of a microsystem changes during both preparation and registration. A new rule that specifies what happens when these changes occur and that guarantees the objectification is formulated and discussed. A part of our result has certain similarities with 'collapse of the wave function'. © 2010 Springer Science+Business Media, LLC. Source


Zurwerra D.,ETH Zurich | Gertsch J.,University of Bern | Altmann K.-H.,ETH Zurich
Organic Letters | Year: 2010

An efficient new synthesis has been elaborated for non-natural (-)-dactylolide ((-)-2) and its 13-desmethylene analogue 4, employing a HWE-based macrocyclization approach with β-keto-phosphonate/aldehyde 19 and the respective 13-desmethylene derivative as the key intermediates. Both (-)-2 and 4 as well as the corresponding C20 alcohols inhibit human cancer cell proliferation with IC 50 values in the sub-micromolar range and induce the polymerization of tubulin in vitro. © 2010 American Chemical Society. Source


Ghiglieri J.,University of Bern
Nuclear and Particle Physics Proceedings | Year: 2016

We report on a recent next-to-leading order perturbative determination of the dilepton rate from a hot QCD plasma for frequency and momentum of the order of the temperature and for much smaller invariant mass M~. gT. We briefly review the calculation, which generalizes the previous one for the photon case (M= 0). We then analyze the consequences of the new calculation for the extraction of the photon rate from the small mass dilepton measurements. We then review a recent NLO determination at large M and we show how to match and merge its results with the low-mass ones, resulting in a single rate which is NLO-accurate over the phenomenologically relevant region. © 2016 Elsevier B.V. Source


Garweg J.G.,University of Bern | Stanford M.R.,Medical Eye Unit
Ocular Immunology and Inflammation | Year: 2013

Background: Treatment of ocular toxoplasmosis is aimed at stabilizing visual function and reducing recurrence rates. Methods: Small controlled studies indicate that available treatments do not affect visual outcome and recurrence rates, and no antibiotic in current use will kill bradyzoites. Results: Antiparasitic treatment is justified in center-involving lesions and in large aggressive lesions namely in South American patients. Antibiotic treatment is needed for disease in the immunosuppressed, and this needs to be systemic. There exists strong agreement that a monotherapy, using steroids, is contraindicated. Prophylactic antibiotics may reduce recurrence rates in endemic areas and immunosuppressed patients. Conclusion: An ideal therapeutic strategy includes the strain of parasite, localization of the lesion, and severity of the inflammatory response as a basis for therapeutic decision making. New treatments targeting aspects of the parasite s physiology are very promising. On a global scale, public health measures to prevent transmission from animals and to access potable water are required. © Informa Healthcare USA, Inc. Source


Styp-Rekowska B.,University of Bern
Acta physiologica (Oxford, England) | Year: 2011

Adaptation of vascular networks to functional demands needs vessel growth, vessel regression and vascular remodelling. Biomechanical forces resulting from blood flow play a key role in these processes. It is well-known that metabolic stimuli, mechanical forces and flow patterns can affect gene expression and remodelling of vascular networks in different ways. For instance, in the sprouting type of angiogenesis related to hypoxia, there is no blood flow in the rising capillary sprout. In contrast, it has been shown that an increase of wall shear stress initiates the splitting type of angiogenesis in skeletal muscle. Otherwise, during development, both sprouting and intussusception act in parallel in building the vascular network, although with differences in spatiotemporal distribution. Thereby, in addition to regulatory molecules, flow dynamics support the patterning and remodelling of the rising vascular tree. Herewith, we present an overview of angiogenic processes with respect to intussusceptive angiogenesis as related to local haemodynamics. © 2011 The Authors. Acta Physiologica © 2011 Scandinavian Physiological Society. Source


Several intervals have been proposed to quantify the agreement of two methods intended to measure the same quantity in the situation where only one measurement per method and subject is available. The limits of agreement are probably the most well-known among these intervals, which are all based on the differences between the two measurement methods. The different meanings of the intervals are not always properly recognized in applications. However, at least for small-to-moderate sample sizes, the differences will be substantial. This is illustrated both using the width of the intervals and on probabilistic scales related to the definitions of the intervals. In particular, for small-to-moderate sample sizes, it is shown that limits of agreement and prediction intervals should not be used to make statements about the distribution of the differences between the two measurement methods or about a plausible range for all future differences. Care should therefore be taken to ensure the correct choice of the interval for the intended interpretation. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Background: It was found that age and female gender are predisposing factors for hyponatremia in patients taking thiazides. Objective: To investigate whether a relationship exists between age and gender and serum sodium and potassium as well as the prevalence rates in a large population of patients presenting to the emergency department of a university hospital. Methods: In this retrospective analysis we gathered data on age, gender and current diuretic medication of all patients admitted to the emergency department of a large university hospital with measurement of serum sodium and potassium between January 1, 2009 and December 31, 2010. Prevalence rates of and risk factors for electrolyte disorders were calculated on the basis of these data. Results: A total of 20,667 patients were included in the analysis. Serum sodium levels declined significantly with increasing age while serum potassium rose, independent of diuretic medication at presentation. The prevalence rates of hyponatremia and hyperkalemia increased from 2.3% for hyponatremia in patients aged 16-21 years to 16.9% in patients aged >80 years and from 0.8% for hyperkalemia to 10.4%. In the regression analysis, age >60 years was a predictor for the presence of hyponatremia and hyperkalemia as was current use of diuretic medication. Male gender was associated with a decreased prevalence of hyponatremia and hypokalemia, while it was a predictor of hyperkalemia. Conclusions: Sodium levels were lower with increasing age, independent of diuretic intake, while potassium levels were higher. We found dramatically increasing prevalences of hyponatremia and hyperkalemia with increasing age, while no such effect could be found for hypernatremia and hypokalemia. © 2014 S. Karger AG, Basel. Source


Larocque-Tobler I.,University of Bern | Larocque-Tobler I.,INRS - Institute National de la Recherche Scientifique
Journal of Paleolimnology | Year: 2010

The temperature reconstruction obtained from chironomids preserved in the sediment of Egelsee, Switzerland, was partially flawed by the low percentages of fossil taxa represented in the Swiss calibration set (Larocque-Tobler et al. 2009a). Transfer functions (TFs) from other regions, which allow a good representation of the fossil taxa (>80%), could be applied to the fossil assemblages of Egelsee. First, the validity of using two (a Swedish and a North American (NA)) TFs was tested by comparing the chironomid-inferred temperatures with instrumental data. Since good relationships (rPearson = 0. 71 and 0. 61, p = 0. 001 for the NA and Swedish TFs, respectively) were obtained, these two models were used to reconstruct the Late Glacial and early Holocene periods at Egelsee. Reconstructions using both models showed clear cold periods during the Younger Dryas and the so-called 8,200 calibrated years BP event. However, the amplitude of changes during these periods was higher when the NA transfer function was used, probably due to the fact that 37% of the taxa in the core had temperature optima colder in the NA than in the Swedish and Swiss models. The results indicate that TFs from other regions can be applied when they are based on samples with good modern analogues, however, caution should be taken when the amplitude of temperature changes is considered. © 2009 Springer Science+Business Media B.V. Source


Ruhrmann S.,University of Cologne | Schultze-Lutter F.,University of Bern | Klosterkotter J.,University of Cologne
Schizophrenia Research | Year: 2010

Current criteria for an increased risk of developing first-episode psychosis are associated with conversion rates many times higher than the general incidence of psychosis. Yet, non-conversions still outnumber conversions, and conversion rates across and within centres vary considerably, fueling the ongoing debate about clinical and ethical justification of indicated prevention. This debate, however, almost exclusively focuses on the predictive validity of at-risk criteria, thereby widely disregarding the main general finding: persons meeting at-risk criteria already suffer from multiple mental and functional disturbances for those they seek help. Moreover, they exhibit various psychological and cognitive deficits along with morphological and functional cerebral changes. Thereby, the majority of help-seeking at-risk persons fulfils DSM-IV's general criteria for mental disorders (defined as a clinically significant behavioural or psychological syndrome associated with disability and/or severe distress) and clearly have to be considered as 'ill', i.e., as 'patients' with a need and right for treatment.Hence, the clinical picture defined by current at-risk criteria should be more adequately perceived as not only a still insufficient attempt to define the psychotic prodrome but a psychosis spectrum disorder in its own right - akin to ICD-10's schizotypal disorder - with conversion to psychosis just being one of several outcomes. Such a disorder, whose criteria are proposed and discussed, should initially be part of DSM-V research criteria. Following from this shift in the perception of current at-risk criteria, access to standard medical care would have to be granted, and diagnosis- or symptom- rather than conversion-related interventions would have to be developed. © 2010 Elsevier B.V. Source


Yang Z.,University of Bern
Swiss medical weekly : official journal of the Swiss Society of Infectious Diseases, the Swiss Society of Internal Medicine, the Swiss Society of Pneumology | Year: 2010

The plasticity and self-regenerative properties of stem cells have opened new avenues in regenerative medicine. Greater understanding of the biology of stem cells is followed by growing expectations of a rapid translation into alternative therapeutic options. Recent preclinical studies and clinical trials employing stem and progenitor cells from different sources have shown encouraging results. However, their underlying mechanisms are still poorly understood, the potential adverse effects and the discrepancy in efficacy remain to be further investigated. Their essential role in vessel regeneration has made endothelial progenitor cells (EPC) a suitable candidate for therapeutic applications aiming at tissue revascularisation. Recent evidence suggests that EPC contribute to neovascularisation not only by direct participation in tissue homeostasis but mainly via paracrine mechanisms. In future, novel therapeutic strategies could be based on EPC paracrine factors or synthetic factors, and replace cell transplantation. Source


Leya I.,University of Bern
Geochimica et Cosmochimica Acta | Year: 2011

This study focuses on cosmogenic effects on lithium, boron, and tungsten isotopes in CAIs from carbonaceous chondrites. The results for lithium isotopes have been used to properly correct experimental data obtained by Chaussidon et al. (2006a) for Allende CAI 3529-41 for cosmogenic contributions. After proper correction, the new inferred ratios slightly but systematically differ from the original ones, indicating that the original study slightly overestimated the cosmogenic corrections. A statistical interpretation of the data indicates that there is a non-linear correlation between 7Li/6Li and 9Be/6Li that might be interpreted as a disturbed isochron. For boron isotopes, the data obtained here confirm that cosmogenic corrections on the 10Be-10B dating system are indeed very minor and can in most cases be neglected. However, a statistical interpretation of the data demonstrates that the type of the fitting procedure used can significantly change the results. It is demonstrated that a fitting procedure using the uncertainties as weights gives a slope about 50% shallower compared to the slope obtained using a non-weighted fitting procedure (for the same data). Such a difference can be wrongly interpreted as an age difference of about one half-life. The modeled results for tungsten isotopes clearly demonstrate that cosmic-ray effects might be of importance for samples having high Ta/W ratios due to thermal neutron capture on 181Ta to form 182W. This effect does not increase the scatter of the data around the isochron but increases the slope of the isochron and therefore gives too old formation ages for the studied CAIs. Consequently, a proper handling of cosmic-ray induced shifts is necessary for high precision 182Hf-182W dating studies. © 2011 Elsevier Ltd. Source


Stickel F.,University of Bern | Hampe J.,University of Kiel
Gut | Year: 2012

Alcoholic liver disease (ALD) accounts for the majority of chronic liver disease in Western countries. The spectrum of ALD includes steatosis with or without fibrosis in virtually all individuals with an alcohol consumption of >80 g/day, alcoholic steatohepatitis of variable severity in 10-35% and liver cirrhosis in approximately 15% of patients. Once cirrhosis is established, there is an annual risk for hepatocellular carcinoma of 1-2%. Environmental factors such as drinking patterns, coexisting liver disease, obesity, diet composition and comedication may modify the natural course of ALD. Twin studies have revealed a substantial contribution of genetic factors to the evolution of ALD, as demonstrated by a threefold higher disease concordance between monozygotic twins and dizygotic twins. With genotyping becoming widely available, a large number of genetic case-control studies evaluating candidate gene variants coding for proteins involved in the degradation of alcohol, mediating antioxidant defence, the evolution and counteraction of necroinflammation and formation and degradation of extracellular matrix have been published with largely unconfirmed, impeached or even disproved associations. Recently, whole genome analyses of large numbers of genetic variants in several chronic liver diseases including gallstone disease, primary sclerosing cholangitis and non-alcoholic fatty liver disease (NAFLD) have identified novel yet unconsidered candidate genes. Regarding the latter, a sequence variation within the gene coding for patatin-like phospholipase encoding 3 (PNPLA3, rs738409) was found to modulate steatosis, necroinflammation and fibrosis in NAFLD. Subsequently, the same variant was repeatedly confirmed as the first robust genetic risk factor for progressive ALD. Source


Rothkopf A.,Bielefeld University | Rothkopf A.,University of Bern
Journal of Computational Physics | Year: 2013

The standard implementation of the Maximum Entropy Method (MEM) follows Bryan [1] and deploys a Singular Value Decomposition (SVD) to limit the dimensionality of the underlying solution space apriori. Here we present arguments based on the shape of the SVD basis functions and numerical evidence from a mock data analysis, which show that the correct Bayesian solution is not in general recovered with this approach. As a remedy we propose to extend the search basis systematically, which will eventually recover the full solution space and the correct solution. In order to adequately approach problems where an exponentially damped kernel is used, we provide an open-source implementation, using the C/C++ language that utilizes high precision arithmetic adjustable at run-time [2]. The LBFGS algorithm is included in the code in order to attack problems without the need to resort to a particular search space restriction. © 2012 Elsevier Inc. Source


Janner M.,University of Bern
Swiss medical weekly : official journal of the Swiss Society of Infectious Diseases, the Swiss Society of Internal Medicine, the Swiss Society of Pneumology | Year: 2010

Vitamin D is important for bone health. An inadequate supply of vitamin D to the body is associated with a higher fracture risk in the elderly. Young adults with type 1 diabetes are reported to have a lower peak bone mass than healthy individuals, which could possibly lead to an increased fracture risk in the future. The prevalence of vitamin D deficiency in healthy young people is high. Thus, optimal supply of vitamin D may be of particular importance for bone health in children with type 1 diabetes. In this prospective cross-sectional study we measured serum 25-hydroxy-vitamin D, iPTH, total and ionised calcium, phosphate, and alkaline phosphatase in 129 Swiss children and adolescents with type 1 diabetes. Of the 129 subjects 78 (60.5%) were vitamin D deficient, defined as a 25-hydroxy-vitamin-D level below 50 nmol/L. During the winter this number rose to 84.1%. 25-hydroxy-vitamin-D levels showed marked seasonal fluctuations, whereas there was no correlation with diabetes control. Despite the high prevalence of vitamin D deficiency, we found a low prevalence of secondary hyperparathyroidism in vitamin D deficient diabetic children and adolescents. Prevalence of vitamin D deficiency in diabetic children and adolescents is high. Therefore, screening for vitamin D deficiency and supplementation in children with low vitamin D levels may be considered. Source


Llovet J.M.,Mount Sinai School of Medicine | Villanueva A.,Mount Sinai School of Medicine | Lachenmayer A.,University of Bern | Finn R.S.,University of California at Los Angeles
Nature Reviews Clinical Oncology | Year: 2015

Mortality owing to liver cancer has increased in the past 20 years, and the latest estimates indicate that the global health burden of this disease will continue to grow. Most patients with hepatocellular carcinoma (HCC) are still diagnosed at intermediate or advanced disease stages, where curative approaches are often not feasible. Among the treatment options available, the molecular targeted agent sorafenib is able to significantly increase overall survival in these patients. Thereafter, up to seven large, randomized phase III clinical trials investigating other molecular therapies in the first-line and second-line settings have failed to improve on the results observed with this agent. Potential reasons for this include intertumour heterogeneity, issues with trial design and a lack of predictive biomarkers of response. During the past 5 years, substantial advances in our knowledge of the human genome have provided a comprehensive picture of commonly mutated genes in patients with HCC. This knowledge has not yet influenced clinical decision-making or current clinical practice guidelines. In this Review the authors summarize the molecular concepts of progression, discuss the potential reasons for clinical trial failure and propose new concepts of drug development, which might lead to clinical implementation of emerging targeted agents. © 2015 Macmillan Publishers Limited. Source


Alaoui A.,University of Bern | Lipiec J.,Polish Academy of Sciences | Gerke H.H.,Leibniz Center for Agricultural Landscape Research
Soil and Tillage Research | Year: 2011

Compaction and shearing, as well as the rearrangement of soil aggregates and clods due to shrinkage, among other processes, can strongly affect the pore geometry of agricultural soils. These soil structural changes directly affect soil water movement by altering the hydraulic properties that are commonly described by the soil water retention curve (WRC) and the unsaturated hydraulic conductivity function (HCF). This review focuses on recent advances in the understanding and evaluation of changes in hydraulic functions in relation to compacted soil. The development of hydromechanical models due to recent advances with more sophisticated methods enables quantification of the effects of compaction on the hydraulic conductivity functions at the pore scale of aggregated soil. However, it remains unclear how to up-scale the dynamic, in terms of inter-aggregate pore models, into the continuum-scale dual-porosity models in the form of effective parameters, particularly regarding effective hydraulic properties for the preferential flow domain. While hydromechanical models fail to describe water flow and hydraulic conductivity at the relevant scales and water saturation ranges, the continuum-based flow models rely on effective parameters that are mainly empirical or are based on fitting model results to data. Input data usually do not address temporal changes in the arrangement of aggregates induced by soil compaction and shrinkage. This review presents a concept that summarizes the changes in structural and textural porosity upon compaction. It suggests focusing on the extension of existing hydraulic and hydromechanical models to include the pore structural changes that account for the movement and rearrangement of soil aggregates and the resulting changes in the soil hydraulic properties which basically manifest the effects of shearing and compaction on water flow. © 2011 Elsevier B.V. Source


Gantenbein-Ritter B.,University of Bern
Methods in molecular biology (Clifton, N.J.) | Year: 2011

In tissue engineering, a variety of methods are commonly used to evaluate survival of cells inside tissues or three-dimensional (3D) carriers. Among these methods confocal laser scanning microscopy opened accessibility of 3D tissue using live cell imaging into the tissue or 3D scaffolds. However, although this technique is ideally applied to 3D tissue or scaffolds with thickness up to several millimetres, this application is surprisingly rare and scans are often done on slices with thickness <20 μm. Here, we present novel protocols for the staining of 3D tissue (e.g. intervertebral disc tissue) and scaffolds, such as fibrin gels or alginate beads. Source


Donze J.,Brigham and Womens Hospital | Donze J.,Harvard University | Aujesky D.,University of Bern | Williams D.,Brigham and Womens Hospital | And 2 more authors.
JAMA Internal Medicine | Year: 2013

Importance: Because effective interventions to reduce hospital readmissions are often expensive to implement, a score to predict potentially avoidable readmissions may help target the patients most likely to benefit. Objective: To derive and internally validate a prediction model for potentially avoidable 30-day hospital readmissions in medical patients using administrative and clinical data readily available prior to discharge. Design: Retrospective cohort study. Setting:Academicmedicalcenter inBoston,Massachusetts. Participants: All patient discharges from any medical services between July 1, 2009, and June 30, 2010. Main Outcome Measures: Potentially avoidable 30- day readmissions to 3 hospitals of the Partners Health- Care network were identified using a validated computerized algorithm based on administrative data (SQLape). A simple score was developed using multivariable logistic regression, with two-thirds of the sample randomly selected as the derivation cohort and one-third as the validation cohort. Results: Among 10 731 eligible discharges, 2398 discharges (22.3%) were followed by a 30-day readmission, of which 879 (8.5% of all discharges) were identified as potentially avoidable. The prediction score identified 7 independent factors, referred to as the HOSPITAL score: hemoglobin at discharge, discharge from an oncology service, sodium level at discharge, procedure during the index admission, index type of admission, number of admissions during the last 12 months, and length of stay. In the validation set, 26.7% of the patients were classified as high risk, with an estimated potentially avoidable readmission risk of 18.0% (observed, 18.2%). The HOSPITAL score had fair discriminatory power (C statistic, 0.71) and had good calibration. Conclusions and Relevance: This simple prediction model identifies before discharge the risk of potentially avoidable 30-day readmission in medical patients. This score has potential to easily identify patients who may need more intensive transitional care interventions. © 2013 American Medical Association. Source


Zimmerli B.,University of Bern
Schweizer Monatsschrift für Zahnmedizin = Revue mensuelle suisse d'odonto-stomatologie = Rivista mensile svizzera di odontologia e stomatologia / SSO | Year: 2010

Various composite materials are available today for direct restorative techniques. The most well-known materials are the hybrid composites. This technology, based on methacrylates and different types of filler coupled with silanes, has been continuously improved. Disadvantages such as polymerisation shrinkage, bacterial adhesion and side effects due to monomer release still remain. The aim of material development is to eliminate or at least reduce these negative factors by adapting the individual components of the material. With ormocers, the methacrylate has been partially replaced by an inorganic network. According to recent studies, the biocompatibility was not improved in all cases. The development of compomer was an attempt to combine the positive properties of glassionomers with composite technology. This has only partially succeeded, because the fluoride release is low. In an in-situ study, a caries protective effect could be shown at least in the first days following filling placement with concurrent extra-oral demineralisation. By replacing the chain-monomers in the composite matrix by ring-shaped molecules, a new approach to reduce polymerisation shrinkage was investigated. A new group of materials, the siloranes, has been developed. Siloranes are hydrophobic and need to be bonded to the dental hard tissue using a special adhesive system. Long-term clinical studies are still needed to prove the superiority of this new group of materials over modern hybrid composites. Source


The goals of any treatment of cervical spine injuries are: return to maximum functional ability, minimum of residual pain, decrease of any neurological deficit, minimum of residual deformity and prevention of further disability. The advantages of surgical treatment are the ability to reach optimal reduction, immediate stability, direct decompression of the cord and the exiting roots, the need for only minimum external fixation, the possibility for early mobilisation and clearly decreased nursing problems. There are some reasons why those goals can be reached better by anterior surgery. Usually the bony compression of the cord and roots comes from the front therefore anterior decompression is usually the procedure of choice. Also, the anterior stabilisation with a plate is usually simpler than a posterior instrumentation. It needs to be stressed that closed reduction by traction can align the fractured spine and indirectly decompress the neural structures in about 70%. The necessary weight is 2.5 kg per level of injury. In the upper cervical spine, the odontoid fracture type 2 is an indication for anterior surgery by direct screw fixation. Joint C1/C2 dislocations or fractures or certain odontoid fractures can be treated with a fusion of the C1/C2 joint by anterior transarticular screw fixation. In the lower and middle cervical spine, anterior plating combined with iliac crest or fibular strut graft is the procedure of choice, however, a solid graft can also be replaced by filled solid or expandable vertebral cages. The complication of this surgery is low, when properly executed and anterior surgery may only be contra-indicated in case of a significant lesion or locked joints. © Springer-Verlag 2009. Source


Reichenbach S.,University of Bern
Cochrane database of systematic reviews (Online) | Year: 2010

BACKGROUND: Osteoarthritis is the most common form of joint disorder and a leading cause of pain and physical disability. Observational studies suggested a benefit for joint lavage, but recent, sham-controlled trials yielded conflicting results, suggesting joint lavage not to be effective. OBJECTIVES: To compare joint lavage with sham intervention, placebo or non-intervention control in terms of effects on pain, function and safety outcomes in patients with knee osteoarthritis. SEARCH STRATEGY: We searched CENTRAL, MEDLINE, EMBASE, and CINAHL up to 3 August 2009, checked conference proceedings, reference lists, and contacted authors. SELECTION CRITERIA: We included studies if they were randomised or quasi-randomised trials that compared arthroscopic and non-arthroscopic joint lavage with a control intervention in patients with osteoarthritis of the knee. We did not apply any language restrictions. DATA COLLECTION AND ANALYSIS: Two independent review authors extracted data using standardised forms. We contacted investigators to obtain missing outcome information. We calculated standardised mean differences (SMDs) for pain and function, and risk ratios for safety outcomes. We combined trials using inverse-variance random-effects meta-analysis. MAIN RESULTS: We included seven trials with 567 patients. Three trials examined arthroscopic joint lavage, two non-arthroscopic joint lavage and two tidal irrigation. The methodological quality and the quality of reporting was poor and we identified a moderate to large degree of heterogeneity among the trials (I(2) = 65%). We found little evidence for a benefit of joint lavage in terms of pain relief at three months (SMD -0.11, 95% CI -0.42 to 0.21), corresponding to a difference in pain scores between joint lavage and control of 0.3 cm on a 10-cm visual analogue scale (VAS). Results for improvement in function at three months were similar (SMD -0.10, 95% CI -0.30 to 0.11), corresponding to a difference in function scores between joint lavage and control of 0.2 cm on a WOMAC disability sub-scale from 0 to 10. For pain, estimates of effect sizes varied to some degree depending on the type of lavage, but this variation was likely to be explained by differences in the credibility of control interventions: trials using sham interventions to closely mimic the process of joint lavage showed a null-effect. Reporting on adverse events and drop out rates was unsatisfactory, and we were unable to draw conclusions for these secondary outcomes. AUTHORS' CONCLUSIONS: Joint lavage does not result in a relevant benefit for patients with knee osteoarthritis in terms of pain relief or improvement of function. Source


Joppke C.,University of Bern
British Journal of Sociology | Year: 2013

It seems to be impossible for the liberal state to embrace a Christian identity, because 'liberalism' is exactly a device for separating state and religion. Discussing the implications of a recent decision of the European Court of Human Rights, Lautsi v. Italy (2011), I argue that this is not necessarily so. If paired with a liberal commitment to pluralism, a Christian identity might even be more inclusive of minority religions than a narrowly 'liberal' state identity, which has been the dominant response in Western Europe to the challenge of immigrant diversity, especially that of Muslim origins. © London School of Economics and Political Science 2013. Source


Praz F.,University of Bern
EuroIntervention : journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology | Year: 2013

Transcatheter aortic valve implantation is a widely performed procedure for treatment of symptomatic severe aortic stenosis. According to the current literature, major stroke has been reported as occurring in 3-6% of patients during the first 30 days following valve implantation. Several pathological mechanisms may be involved in the development of periprocedural ischaemic stroke with the majority being due to thromboembolism and atheroembolism. One approach to reduce the incidence of procedural cerebral thromboembolic events is the use of cerebral protection devices, either deflecting (Embrella, TriGuard) or capturing (Claret, Embol-X) embolic material. We decided to review the current evidence on this important issue focusing on the four cerebral protection devices currently available. Source


Zimmerli B.,University of Bern
Schweizer Monatsschrift für Zahnmedizin = Revue mensuelle suisse d'odonto-stomatologie = Rivista mensile svizzera di odontologia e stomatologia / SSO | Year: 2010

Today, the bleaching of nonvital, discolored teeth is a low-risk routine treatment for improving esthetics. This review article focuses on the etiology of tooth discolorations, different treatment techniques, and risks of bleaching procedures. Some tooth discolorations in endodontically treated teeth are caused by dental treatments. The three most popular techniques for nonvital tooth bleaching are the walking bleach technique, inside/outside bleaching, and in-office bleaching. The walking bleach technique is a relatively reliable, fairly simple technique for dentists and patients. Inside/outside bleaching can be used additionally when internal and external bleaching must be combined. In-office bleaching seems to be a short-term solution, the effects of which can largely be attributed to dehydration of the teeth. There are still some open questions concerning the bleaching agents. Improved safety seems desirable with regard to adding thiourea as a scavenger of radicals or newer materials such as sodium percarbonate. The thermocatalytic technique, insufficient cervical sealing, and high concentrations of bleaching agents should be avoided, as this can increase the risk of cervical root resorptions. Patients should be informed about the low predictability of bleaching success and the risk of recurrent discoloration. The risk of cervical root resorption should be discussed with the patient. There is a strong correlation between root resorption and dental trauma. Source


Mullis P.-E.,University of Bern
Best Practice and Research: Clinical Endocrinology and Metabolism | Year: 2011

When a child is not following the normal, predicted growth curve, an evaluation for underlying illnesses and central nervous system abnormalities is required and, appropriate consideration should be given to genetic defects causing GH deficiency (GHD). Because Insulin-like-Growth Factor-I (IGF-I) plays a pivotal role, GHD could also be considered as a form of IGF-I deficiency (IGFD). Although IGFD can develop at any level of the GHRH-GH-IGF axis, a differentiation should be made between GHD (absent to low GH in circulation) and IGFD (normal to high GH in circulation). The main focus of this review is on the GH-gene, the various gene alterations and their possible impact on the pituitary gland. However, although transcription factors regulating the pituitary gland development may cause multiple pituitary hormone deficiency they may present initially as GHD. These defects are discussed in various different chapters within this book, whereas, the impact of alterations of the GHRH-, GHRH-receptor - as well as the GH-receptor (GHR) gene will be discussed here. © 2010 Elsevier Ltd. All rights reserved. Source


Chang H.-M.,University of California at San Diego | Procura M.,University of Bern | Thaler J.,Massachusetts Institute of Technology | Waalewijn W.J.,University of California at San Diego
Physical Review Letters | Year: 2013

By using observables that only depend on charged particles (tracks), one can efficiently suppress pileup contamination at the LHC. Such measurements are not infrared safe in perturbation theory, so any calculation of track-based observables must account for hadronization effects. We develop a formalism to perform these calculations in QCD, by matching partonic cross sections onto new nonperturbative objects called track functions which absorb infrared divergences. The track function Ti(x) describes the energy fraction x of a hard parton i which is converted into charged hadrons. We give a field-theoretic definition of the track function and derive its renormalization group evolution, which is in excellent agreement with the pythia parton shower. We then perform a next-to-leading order calculation of the total energy fraction of charged particles in e+e-→ hadrons. To demonstrate the implications of our framework for the LHC, we match the pythia parton shower onto a set of track functions to describe the track mass distribution in Higgs plus one jet events. We also show how to reduce smearing due to hadronization fluctuations by measuring dimensionless track-based ratios. © 2013 American Physical Society. Source


Messerli B.,University of Bern
Mountain Research and Development | Year: 2012

The history of mountain research is most fascinating. Three names for 3 centuries may give an idea of the growing knowledge about the world's mountains: Horace Bndict de Saussure, who climbed and studied the Mont Blanc in 1787; Alexander von Humboldt, ever investigating the environment during his attempt to ascend the Chimborazo in 1802; and Carl Troll, who founded the International Geographical Union's Commission on High-altitude Geoecology in 1968. Awareness of the growing impact of human activities on the environment led to scientific and political initiatives at the global level, beginning in the 1970s. The Perth conference in 2010 has offered an opportunity to both look back on these developments and explore the future of the world's mountains in a time of rapidly growing "global change" problems and processes. © 2012 by the authors. Source


Alibert Y.,University of Bern
Astronomy and Astrophysics | Year: 2014

Context. The conditions that a planet must fulfill to be habitable are not precisely known. However, it is comparatively easier to define conditions under which a planet is very likely not habitable. Finding such conditions is important as it can help select, in an ensemble of potentially observable planets, which ones should be observed in greater detail for characterization studies. Aims. Assuming, as in the Earth, that the presence of a C-cycle is a necessary condition for long-term habitability, we derive, as a function of the planetary mass, a radius above which a planet is likely not habitable. We compute the maximum radius a planet can have to fulfill two constraints: surface conditions compatible with the existence of liquid water, and no ice layer at the bottom of a putative global ocean. We demonstrate that, above a given radius, these two constraints cannot be met. Methods. We compute internal structure models of planets, using a five-layer model (core, inner mantle, outer mantle, ocean, and atmosphere), for different masses and composition of the planets (in particular, the Fe/Si ratio of the planet). Results. Our results show that for planets in the super-Earth mass range (1-12 M ⊕), the maximum that a planet, with a composition similar to that of the Earth, can have varies between 1.7 and 2.2 R ⊕. This radius is reduced when considering planets with higher Fe/Si ratios and taking radiation into account when computing the gas envelope structure. Conclusions. These results can be used to infer, from radius and mass determinations using high-precision transit observations like those that will soon be performed by the CHaracterizing ExOPlanet Satellite (CHEOPS), which planets are very likely not habitable, and therefore which ones should be considered as best targets for further habitability studies. © 2013 ESO. Source


Asatrian H.M.,Yerevan Physics Institute | Greub C.,University of Bern
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

We evaluate the most important tree-level contributions connected with the b→uūdγ transition to the inclusive radiative decay B̄→Xdγ using fragmentation functions. In this framework the singularities arising from collinear photon emission from the light quarks (u, ū, and d) can be absorbed into the (bare) quark-to-photon fragmentation function. We use as input the fragmentation function extracted by the ALEPH group from the two-jet cross section measured at the large electron positron (LEP) collider, where one of the jets is required to contain a photon. To get the quark-to-photon fragmentation function at the fragmentation scale μF∼mb, we use the evolution equation, which we solve numerically. We then calculate the (integrated) photon energy spectrum for b→uūdγ related to the operators P1,2u. For comparison, we also give the corresponding results when using nonzero (constituent) masses for the light quarks. © 2013 American Physical Society. Source


Simon H.-U.,University of Bern | Klion A.,National Institute of Allergy and Infectious Diseases
Seminars in Hematology | Year: 2012

Hypereosinophilic syndromes (HES) are a heterogeneous group of disorders that range from asymptomatic eosinophilia >1,500/mL to aggressive disease complicated by life-threatening end organ involvement, including endomyocardial fibrosis and thromboembolism. To complicate matters further, similar clinical manifestations can occur in the setting of marked eosinophilia due to helminth infection, drug hypersensitivity, and other causes. In the past, therapy was guided only by the exclusion of these secondary causes of eosinophilia and the severity of the clinical manifestations. More recently, the availability of novel targeted therapies and a better understanding of the etiologies of some subtypes of HES have necessitated a more structured approach. © 2012. Source


Fang W.,Princeton University | Wang X.,Princeton University | Bracht J.R.,Princeton University | Nowacki M.,University of Bern | Landweber L.F.,Princeton University
Cell | Year: 2012

Genome duality in ciliated protozoa offers a unique system to showcase their epigenome as a model of inheritance. In Oxytricha, the somatic genome is responsible for vegetative growth, whereas the germline contributes DNA to the next sexual generation. Somatic nuclear development removes all transposons and other so-called "junk" DNA, which comprise ∼95% of the germline. We demonstrate that Piwi-interacting small RNAs (piRNAs) from the maternal nucleus can specify genomic regions for retention in this process. Oxytricha piRNAs map primarily to the somatic genome, representing the ∼5% of the germline that is retained. Furthermore, injection of synthetic piRNAs corresponding to normally deleted regions leads to their retention in later generations. Our findings highlight small RNAs as powerful transgenerational carriers of epigenetic information for genome programming. © 2012 Elsevier Inc. Source


Chang W.,University of California at San Diego | Zwicker M.,University of Bern
ACM Transactions on Graphics | Year: 2011

We present the articulated global registration algorithm to reconstruct articulated 3D models from dynamic range scan sequences. This new algorithm aligns multiple range scans simultaneously to reconstruct a full 3D model from the geometry of these scans. Unlike other methods, we express the surface motion in terms of a reduced deformable model and solve for joints and skinning weights. This allows a user to interactively manipulate the reconstructed 3D model to create new animations. We express the global registration as an optimization of both the alignment of the range scans and the articulated structure of the model. We employ a graph-based representation for the skinning weights that successfully handles difficult topological cases well. Joints between parts are estimated automatically and are used in the optimization to preserve the connectivity between parts. The algorithm also robustly handles difficult cases where parts suddenly disappear or reappear in the range scans. The global registration produces a more accurate registration compared to a sequential registration approach, because it estimates the articulated structure based on the motion observed in all input frames. We show that we can automatically reconstruct a variety of articulated models without the use of markers, user-placed correspondences, segmentation, or template model. © 2011 ACM 0730-0301/2011/05-ART26. Source


Guarino A.,University of Bern
Journal of High Energy Physics | Year: 2014

We revise the SU(3)-invariant sector of N = 8 supergravity with dyonic SO(8) gaugings. By using the embedding tensor formalism, analytic expressions for the scalar potential, superpotential(s) and fermion mass terms are obtained as a function of the electromagnetic phase ω and the scalars in the theory. Equipped with these results, we explore non-supersymmetric AdS critical points at ω ≠ 0 for which perturbative stability could not be analysed before. The ω-dependent superpotential is then used to derive first-order flow equations and obtain new BPS domain-wall solutions at ω ≠ 0. We numerically look at steepest-descent paths motivated by the (conjectured) RG flows. Source


Rothkopf A.,University of Bern
Journal of High Energy Physics | Year: 2014

We investigate the phenomenon of Bottomonium melting in a thermal quark-gluon plasma using three-dimensional stochastic simulations based on the concept of open-quantum systems. In this non-relativistic framework, introduced in [1], which makes close contact to the potentials derived in effective field theory, the bb system evolves unitarily under the incessant kicks by the constituents of the surrounding heat bath. In particular thermal fluctuations and the presence of a complex potential in the EFT are naturally related. An intricate interplay between state mixing and thermal excitations emerges as we show how non-thermal initial conditions of Bottomonium states evolve over time. We emphasize that the dynamics of these states gives us access to information beyond what is encoded in the thermal Bottomonium spectral functions. Assumptions underlying our approach and their limitations, as well as the refinements necessary to connect to experimental measurements under more realistic conditions are discussed. © 2014 The Author(s). Source


Armas J.,University of Bern
Journal of High Energy Physics | Year: 2014

Abstract: We construct the theory of dissipative hydrodynamics of uncharged fluids living on embedded space-time surfaces to first order in a derivative expansion in the case of codimension-1 surfaces (including fluid membranes) and the theory of non-dissipative hydrodynamics to second order in a derivative expansion in the case of codimension higher than one under the assumption of no angular momenta in transverse directions to the surface. This construction includes the elastic degrees of freedom, and hence the corresponding transport coefficients, that take into account transverse fluctuations of the geometry where the fluid lives. Requiring the second law of thermodynamics to be satisfied leads us to conclude that in the case of codimension-1 surfaces the stress-energy tensor is characterized by 2 hydrodynamic and 1 elastic independent transport coefficient to first order in the expansion while for codimension higher than one, and for non-dissipative flows, the stress-energy tensor is characterized by 7 hydrodynamic and 3 elastic independent transport coefficients to second order in the expansion. Furthermore, the constraints imposed between the stress-energy tensor, the bending moment and the entropy current of the fluid by these extra non-dissipative contributions are fully captured by equilibrium partition functions. This analysis constrains the Young modulus which can be measured from gravity by elastically perturbing black branes. © 2014, The Author(s). Source


Becher T.,University of Bern | Bell G.,University of Oxford
Physical Review Letters | Year: 2014

We show that nonperturbative effects are logarithmically enhanced for transverse-momentum-dependent observables such as qT spectra of electroweak bosons in hadronic collisions and jet broadening at e+e- colliders. This enhancement arises from the collinear anomaly, a mechanism characteristic for transverse observables, which induces logarithmic dependence on the hard scale in the product of the soft and collinear matrix elements. Our analysis is based on an operator product expansion and provides, for the first time, a systematic, model-independent way to study nonperturbative effects for this class of observables. For the case of jet broadening, we relate the leading correction to the nonperturbative shift of the thrust distribution. © 2014 American Physical Society. Source


Armas J.,University of Bern | Harmark T.,Copenhagen University
Journal of High Energy Physics | Year: 2014

We develop further the effective fluid theory of stationary branes. This formalism applies to stationary blackfolds as well as to other equilibrium brane systems at finite temperature. The effective theory is described by a Lagrangian containing the information about the elastic dynamics of the brane embedding as well as the hydrodynamics of the effective fluid living on the brane. The Lagrangian is corrected order-by-order in a derivative expansion, where we take into account the dipole moment of the brane which encompasses finite-thickness corrections, including transverse spin. We describe how to extract the thermodynamics from the Lagrangian and we obtain constraints on the higherderivative terms with one and two derivatives. These constraints follow by comparing the brane thermodynamics with the conserved currents associated with background Killing vector fields. In particular, we fix uniquely the one- and two-derivative terms describing the coupling of the transverse spin to the background space-time. Finally, we apply our formalism to two blackfold examples, the black tori and charged black rings and compare the latter to a numerically generated solution. © The Authors. Source


Frick A.,University of Bern | Mohring W.,Temple University | Newcombe N.S.,Temple University
Trends in Cognitive Sciences | Year: 2014

Mental representation and transformation of spatial information is often examined with mental rotation (MR) tasks, which require deciding whether a rotated image is the same as or the mirror version of an upright image. Recent research with infants shows early discrimination of objects from mirror-image versions. However, even at the age of 4 years, many children perform at near chance level on more standard measures. Similar age discrepancies can be observed in other domains, including perspective taking, theory of mind, and intuitive physics. These paradoxical results raise the questions of how performance relates to competence and how to conceptualize developmental change. There may be a common underlying mechanism: the development of the ability to imagine things and mentally transform them in a prospective fashion. © 2014 Elsevier Ltd. Source


Eick S.,University of Bern
Quintessence international (Berlin, Germany : 1985) | Year: 2011

To determine in vitro the action of chlorhexidine digluconate and different commercially available mouthrinses on oral microorganisms. Minimal inhibitory concentrations and possible induction of resistance by chlorhexidine digluconate, an essential oil-containing mouthwash and an amine fluoride/stannous fluoride solution, were determined against microorganisms normally found in the oral cavity (10 streptococci, 2 enterobacteria, 1 Candida albicans, 8 Porphyromonas gingivalis, 6 Aggregatibacter actinomycetemcomitans, and 1 Fusobacterium nucleatum). Further, the effect of a 1-minute exposure on cell and bacterial viability was studied. The susceptibility of the oral microorganisms to chlorhexidine digluconate ranged from 0.01% to 0.50%. Passages on agar plates containing subinhibitory concentrations of chlorhexidine digluconate resulted in a transitory moderate increase in the tolerance to chlorhexidine digluconate in five of the 24 isolates. After 1 minute of exposure, chlorhexidine digluconate solutions as well as the essential oil and the amine/stannous fluoride-containing solutions showed a high activity against the tested microorganisms. Commercially available chlorhexidine digluconate formulations (ie, those with antidiscoloration systems) were partly less efficient than the corresponding manually prepared chlorhexidine digluconate preparation. The determination of MTT resulted in a strong cytotoxicity of all tested preparations to gingival fibroblasts. The results indicate that most of the chlorhexidine digluconate formulations as well as essential oil and the amine fluoride/stannous fluoride solutions are active against oral microbes. Long-term use of these agents would not result in emergent antimicrobial resistance. Source


Whiting P.F.,University of Bristol | Rutjes A.W.S.,University of Bern | Westwood M.E.,Kleijnen Systematic Reviews | Mallett S.,Wolfson College Annexe | And 5 more authors.
Annals of Internal Medicine | Year: 2011

In 2003, the QUADAS tool for systematic reviews of diagnostic accuracy studies was developed. Experience, anecdotal reports, and feedback suggested areas for improvement; therefore, QUADAS-2 was developed. This tool comprises 4 domains: patient selection, index test, reference standard, and flow and timing. Each domain is assessed in terms of risk of bias, and the first 3 domains are also assessed in terms of concerns regarding applicability. Signalling questions are included to help judge risk of bias. © 2011 American College of Physicians. Source


Pfister J.,University of Bern
Journal of Pragmatics | Year: 2010

In this article two arguments are given in support of a maxim of politeness. The first argument is that assuming a maxim is part of the best explanation of polite behaviour, considering the problems, which Brown and Levinson's theory and Fraser and Nolen's conversational contract theory have, and which a maxim-based theory does not have. The second argument is that the maxim of politeness is part of rational conversation among potentially aggressive parties. This leads to a new Gricean theory of politeness: the maxim of politeness is seen as an additional conversational maxim under the Cooperative Principle in rational conversations among potentially aggressive parties. The content of the maxim is then determined face-theoretically, incorporating some of Brown and Levinson's ideas into the Gricean theory. © 2009 Elsevier B.V. All rights reserved. Source


Jutzi M.,University of Bern
Planetary and Space Science | Year: 2015

We present recent improvements of the modeling of the disruption of strength dominated bodies using the Smooth Particle Hydrodynamics (SPH) technique. The improvements include an updated strength model and a friction model, which are successfully tested by a comparison with laboratory experiments. In the modeling of catastrophic disruptions of asteroids, a comparison between old and new strength models shows no significant deviation in the case of targets which are initially non-porous, fully intact and have a homogeneous structure (such as the targets used in the study by Benz and Asphaug, 1999). However, for many cases (e.g. initially partly or fully damaged targets and rubble-pile structures) we find that it is crucial that friction is taken into account and the material has a pressure dependent shear strength. Our investigations of the catastrophic disruption threshold Q∗D as a function of target properties and target sizes up to a few 100 km show that a fully damaged target modeled without friction has a Q∗D which is significantly (5-10 times) smaller than in the case where friction is included. When the effect of the energy dissipation due to compaction (pore crushing) is taken into account as well, the targets become even stronger (Q∗D is increased by a factor of 2-3). On the other hand, cohesion is found to have an negligible effect at large scales and is only important at scales ≲1 km. Our results show the relative effects of strength, friction and porosity on the outcome of collisions among small (≲1000 km) bodies. These results will be used in a future study to improve existing scaling laws for the outcome of collisions (e.g. Leinhardt and Stewart, 2012). © 2014 Published by Elsevier Ltd. Source


Crivellin A.,University of Bern | Najjari S.,University of Warsaw | Rosiek J.,University of Warsaw
Journal of High Energy Physics | Year: 2014

We study lepton flavor observables in the Standard Model (SM) extended with all dimension-6 operators which are invariant under the SM gauge group. We calculate the complete one-loop predictions to the radiative lepton decays μ → eγ, φ → μγ and φ → eγ as well as to the closely related anomalous magnetic moments and electric dipole moments of charged leptons, taking into account all dimension-6 operators which can generate lepton flavor violation. Also the 3-body flavor violating charged lepton decays φ± → μ±μ+μ,φ± → e±e+e, φ± → e±μ+μ, φ± → μ±e+e, φ± → eμ±μ±, φ± → μe±e± and μ± → e±e+e and the Z0 decays Z0 → +i j are considered, taking into account all tree-level contributions. © The Authors. Source


Zywicki M.,Innsbruck Medical University | Zywicki M.,Adam Mickiewicz University | Bakowska-Zywicka K.,Innsbruck Medical University | Polacek N.,University of Bern
Nucleic Acids Research | Year: 2012

The exploration of the non-protein-coding RNA (ncRNA) transcriptome is currently focused on profiling of microRNA expression and detection of novel ncRNA transcription units. However, recent studies suggest that RNA processing can be a multi-layer process leading to the generation of ncRNAs of diverse functions from a single primary transcript. Up to date no methodology has been presented to distinguish stable functional RNA species from rapidly degraded side products of nucleases. Thus the correct assessment of widespread RNA processing events is one of the major obstacles in transcriptome research. Here, we present a novel automated computational pipeline, named APART, providing a complete workflow for the reliable detection of RNA processing products from next-generation-sequencing data. The major features include efficient handling of non-unique reads, detection of novel stable ncRNA transcripts and processing products and annotation of known transcripts based on multiple sources of information. To disclose the potential of APART, we have analyzed a cDNA library derived from small ribosome-associated RNAs in Saccharomyces cerevisiae. By employing the APART pipeline, we were able to detect and confirm by independent experimental methods multiple novel stable RNA molecules differentially processed from well known ncRNAs, like rRNAs, tRNAs or snoRNAs, in a stress-dependent manner. © 2012 The Author(s). Source


Aebi C.,University of Bern
Advances in Experimental Medicine and Biology | Year: 2011

Moraxella catarrhalis is an exclusively human commensal and mucosal pathogen. Its role as a disease-causing organism has long been questioned. Today, it is recognized as one of the major causes of acute otitis media in children, and its relative frequency of isolation from both the nasopharynx and the middle ear cavity has increased since the introduction of the heptavalent pneumococcal conjugate vaccine, which is associated with a shift in the composition of the nasopharyngeal flora in infants and young children. Although otitis media caused by M. catarrhalis is generally believed to be mild in comparison with pneumococcal disease, numerous putative virulence factors have now been identified and it has been shown that several surface components of M. catarrhalis induce mucosal inflammation. In adults with chronic obstructive pulmonary disease (COPD), M. catarrhalis is now a well-established trigger of approximately 10% of acute inflammatory exacerbations. Although the so-called cold shock response is a well-described bacterial stress response in species such as Escherichia coli, Bacillus subtilis or - more recently - Staphylococcus aureus, M. catarrhalis is the only typical nasopharyngeal pathogen in which this response has been investigated. Indeed, a 3-h 26°C cold shock, which may occur physiologically, when humans inspire cold air for prolonged periods of time, increases epithelial cell adherence and enhances proinflammatory host responses and may thus contribute to the symptoms referred to as common cold, which typically are attributed to viral infections. © 2011 Springer Science+Business Media, LLC. Source


Hasler G.,University of Bern | Northoff G.,Ottawa Health Research Institute
Molecular Psychiatry | Year: 2011

Psychiatry research lacks an in-depth understanding of mood disorders phenotypes, leading to limited success of genetics studies of major depressive disorder (MDD). The dramatic progress in safe and affordable magnetic resonance-based imaging methods has the potential to identify subtle abnormalities of neural structures, connectivity and function in mood disordered subjects. This review paper presents strategies to improve the phenotypic definition of MDD by proposing imaging endophenotypes derived from magnetic resonance spectroscopy measures, such as cortical gamma-amino butyric acid (GABA) and glutamate/glutamine concentrations, and from measures of resting-state activity and functional connectivity. The proposed endophenotypes are discussed regarding specificity, mood state-independence, heritability, familiarity, clinical relevance and possible associations with candidate genes. By improving phenotypic definitions, the discovery of new imaging endophenotypes will increase the power of candidate gene and genome-wide associations studies. It will also help to develop and evaluate novel therapeutic treatments and enable clinicians to apply individually tailored therapeutic approaches. Finally, improvements of the phenotypic definition of MDD based on neuroimaging measures will contribute to a new classification system of mood disorders based on etiology and pathophysiology. © 2011 Macmillan Publishers Limited All rights reserved. Source


Albrecht M.,University of Bern
Angewandte Chemie - International Edition | Year: 2015

, Wiley-VCH, Weinheim 2014. 568 pp., € 149.00.-ISBN 978-3527334902 © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Vial F.,University of Bern | Reist M.,Federal Food Safety and Veterinary Office
BMC Veterinary Research | Year: 2014

Background: We evaluated Swiss slaughterhouse data for integration in a national syndromic surveillance system for the early detection of emerging diseases in production animals. We analysed meat inspection data for cattle, pigs and small ruminants slaughtered between 2007 and 2012 (including emergency slaughters of sick/injured animals); investigating patterns in the number of animals slaughtered and condemned; the reasons invoked for whole carcass condemnations; reporting biases and regional effects.Results: Whole carcass condemnation rates were fairly uniform (1-2‰) over time and between the different types of production animals. Condemnation rates were much higher and less uniform following emergency slaughters. The number of condemnations peaked in December for both cattle and pigs, a time when individuals of lower quality are sent to slaughter when hay and food are limited and when certain diseases are more prevalent. Each type of production animal was associated with a different profile of condemnation reasons. The most commonly reported one was " severe lesions" for cattle, " abscesses" for pigs and " pronounced weight loss" for small ruminants. These reasons could constitute valuable syndromic indicators as they are unspecific clinical manifestations of a large range of animal diseases (as well as potential indicators of animal welfare). Differences were detected in the rate of carcass condemnation between cantons and between large and small slaughterhouses. A large percentage (>60% for all three animal categories) of slaughterhouses operating never reported a condemnation between 2007 and 2012, a potential indicator of widespread non-reporting bias in our database.Conclusions: The current system offers simultaneous coverage of cattle, pigs and small ruminants for the whole of Switzerland; and traceability of each condemnation to its farm of origin. The number of condemnations was significantly linked to the number of slaughters, meaning that the former should be always be offset by the later in analyses. Because this denominator is only communicated at the end of the month, condemnations may currently only be monitored on a monthly basis. Coupled with the lack of timeliness (30-60 days delay between condemnation and notification), this limits the use of the data for early-detection. © 2014 Vial and Reist; licensee BioMed Central Ltd. Source


Background. Current guidelines suggest that primary prophylaxis for Pneumocystis jiroveci pneumonia (PcP) can be safely stopped in human immunodeficiency virus (HIV)-infected patients who are receiving combined antiretroviral therapy (cART) and who have a CD4 cell count >200 cells/μL. There are few data regarding the incidence of PcP or safety of stopping prophylaxis in virologically suppressed patients with CD4 cell counts of 101-200 cells/μL. Methods. The Opportunistic Infections Project Team of the Collaboration of Observational HIV Epidemiological Research in Europe (COHERE) included data from 23,412 patients from 12 European cohorts who started taking cART after 1997. Poisson regression was used to model incidence rate ratios (IRRs) of primary PcP. Results. There were 253 PcP cases during 107,016 person-years of follow-up (PYFU). Prophylaxis significantly reduced the incidence of PcP among patients with current CD4 cell counts ≤100 cells/mL (adjusted IRR, 0.41; 95% confidence interval [CI], 0.27-0.60) but not significantly among those with current CD4 cell counts of 101- 200 cells/μL (adjusted IRR, 0.63; 95% CI, 0.34-1.17). The incidence of PcP among patients who had a current CD4 cell count of 100-200 cells/μL, who had a viral load <400 copies/mL, and who were receiving prophylaxis was 2.1 cases per 1000 PYFU (95% CI, 0.8-4.3 cases per 1000 PYFU; 7 events occurred during 3363 PYFU), whereas 1.2 cases per 1000 PYFU (95% CI, 0.2-4.5 cases per 1000 PYFU; 2 events occurred during 1614 PYFU) occurred among persons who were not receiving prophylaxis (adjusted IRR, 1.65; 95% CI, 0.33-8.15). Among patients who discontinued PcP prophylaxis after starting cART, the incidence of primary PcP was 0 cases per 1000 PYFU (95% CI, 0.0-2.7 cases per 1000 PYFU; 0 events occurred during 1363 PYFU) for patients who had a current CD4 cell count of 101-200 cells/μL and who were receiving cART. Conclusions. The incidence of primary PcP among patients who had virologically suppressed HIV infection, were receiving cART, and who had CD4 cell counts >100 cells/μL was low irrespective of prophylaxis use. Discontinuation of prophylaxis may be safe in patients with CD4 counts of 101-200 cells/μL and suppressed viral load. © 2010 by the Infectious Diseases Society of America. Source


Haralambus R.M.,University of Bern
Veterinary surgery : VS : the official journal of the American College of Veterinary Surgeons | Year: 2010

To report use of a pinless external fixator (PEF) for unilateral mandibular fractures in 9 equids. Case series. Equids (n=9) with unilateral mandibular fractures. All fractures were stabilized with the AO/ASIF PEF using a minimum of 4 clamps, under general anesthesia. Fracture configuration, complications, outcome, and owner satisfaction were evaluated. All fractures were stabilized; 2 equids were euthanatized; 1 because of an inability to stand after surgery and 1 because of owner decision after PEF dislodgement. Seven repairs healed with good outcome and owner satisfaction. Complications included dislodgement of the PEF (3), bone sequestration (3), and weight loss (1). Drainage associated with repair resolved after removal of sequestra and clamps. Stabilization of unilateral mandibular fractures with the PEF in horses was minimally invasive with minimal risk of tooth root interference; however, after care is time consuming. PEF is an alternative technique for stabilizing unilateral mandibular fractures in equids. Source


Brindley M.A.,Georgia State University | Plattet P.,University of Bern | Plemper R.K.,Georgia State University
Proceedings of the National Academy of Sciences of the United States of America | Year: 2014

Enveloped viruses such as HIV and members of the paramyxovirus family use metastable, proteinaceous fusion machineries to merge the viral envelope with cellular membranes for infection. A hallmark of the fusogenic glycoproteins of these pathogens is refolding into a thermodynamically highly stable fusion core structure composed of six antiparallel α-helices, and this structure is considered instrumental for pore opening and/or enlargement. Using a paramyxovirus fusion (F) protein, we tested this paradigm by engineering covalently restricted F proteins that are predicted to be unable to close the six-helix bundle core structure fully. Several candidate bonds formed efficiently, resulting in F trimers and higher-order complexes containing covalently linked dimers. The engineered F complexes were incorporated into recombinant virions efficiently and were capable of refolding into a postfusion conformation without temporary or permanent disruption of the disulfide bonds. They efficiently formed fusion pores based on virus replication and quantitative cell-to-cell and virus-to-cell fusion assays. Complementation of these F mutants with a monomeric, fusion-inactive F variant enriched the F oligomers for heterotrimers containing a single disulfide bond, without affecting fusion complementation profiles compared with standard F protein. Our demonstration that complete closure of the fusion core does not drive paramyxovirus entry may aid the design of strategies for inhibiting virus entry. Source


Roman S.,University of Lyon | Tutuian R.,University of Bern
Neurogastroenterology and Motility | Year: 2012

Background Esophageal motility abnormalities include a series of manometric findings that differ to a significant degree from findings in normal, asymptomatic volunteers. Methods Current review summarizes conventional and high-resolution esophageal manometry criteria used to define and characterize esophageal hypertensive motility abnormalities. Key Results In the conventional esophageal manometry classification scheme hypertensive esophageal motility abnormalities include nutcracker esophagus (average distal contraction amplitude >180mmHg), hypertensive lower esophageal sphincter (average resting LES pressure >45mmHg) and poorly relaxing lower esophageal sphincter (average LES residual pressure >8mmHg). The new, high resolution esophageal manometry scheme includes in the group of hypertensive peristaltic disorders hypertensive peristalsis ("nutcracker esophagus": mean DCI >5000 mmHg*sec*cm) and hypercontractile esophagus ("jackhammer esophagus": at least one contraction with DCI > 8,000 mmHg*sec*cm) and defines a separate group for disorders with impaired esophageal-gastric junction relaxation (mean integrated residual (LES) pressure >15mmHg). Conclusions & Inferences Hypertensive motility disorders represent a heterogeneous condition subdivided into hypercontractile esophagus and hypertensive peristalsis. Further studies are required to determine the clinical relevance of this new classification. © 2012 Blackwell Publishing Ltd. Source


Aymard T.,University of Bern
European journal of cardio-thoracic surgery : official journal of the European Association for Cardio-thoracic Surgery | Year: 2013

The treatment of massive pulmonary embolism (PE) is a matter of debate. We present our institutional experience of patients suffering from massive PE with the aim of comparing the early results, the outcome and quality of life (QoL) between patients primarily assigned to either pulmonary surgical embolectomy (SE) or thrombolytic therapy (TL). A subgroup of patients (TS) with failed responses to TL requiring SE was separately analysed. All consecutive patients (January 2001-December 2007) with computed tomography (CT)-scan-confirmed massive bilateral central or paracentral PE were reviewed. All clinical data were retrieved from our patients' registry and completed by the evaluation of the CT-scan-derived right ventricle/left ventricle ratio (RV/LV ratio). Follow-up focused on clinical outcome and QoL was obtained. Eighty patients were analysed including 28 SE (35%) and 52 TL (65%), of whom 11 (21%) required TS. Demographics and preoperative characteristics were similar between SE and TL. Analysis of the RV/LV ratio revealed a ratio of 1.66 for SE and 1.44 for TL. The early mortality rate was not significantly different between the two groups (SE: 3.6% versus TL: 13.5%), whereas early mortality was 27% in those patients treated initially with thrombolysis and subsequently requiring SE (TS-group). Severe bleeding complications were lower in the SE-group (3.6% versus 26.5% P = 0.013). Intracerebral bleeding rates and neurological events were not statistically different. After a mean follow-up of 63 ± 21 months, the mortality rate was 17.9% in the SE-group and 23.1% in the TL-group. SE is an excellent treatment option in massive PE with comparable early mortality rates and significantly less bleeding complications than TL. Patients having surgery after inefficient thrombolysis have the worst early outcome. The RV/LV CT-scan ratio might serve as a predictor to differentiate patients, who could profit from direct surgical intervention than thrombolytic treatment attempts. Further studies are required to confirm these results. Source


Stortecky S.,University of Bern
EuroIntervention : journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology | Year: 2012

Transcatheter aortic valve implantation (TAVI) is an evidence-based treatment alternative for selected high-risk patients with symptomatic severe aortic stenosis as acknowledged in the most recent edition of the ESC Guidelines on Valvular Heart Disease 2012. However, periprocedural complications and in particular cerebrovascular accidents remain a matter of concern. While transcatheter heart valve technology continuously improves and the development of novel and even less invasive implantation techniques is on-going, cerebrovascular events complicating TAVI may abrogate the usual improvement in terms of prognosis and quality of life. This article describes the incidence of cerebrovascular events after cardiovascular procedures, provides an overview of the pathophysiological mechanisms as well as the impact on outcomes and provides some insights into preventive strategies as well as the acute management of these events. Source


Kucher N.,University of Bern
New England Journal of Medicine | Year: 2011

A 58-year-old woman presents with a 3-day history of pain, heaviness, and functional impairment in her left arm. She has received chemotherapy for ovarian cancer through an implanted port and catheter (Port-a-Cath) on the left side. Physical examination reveals a swollen and erythematous left arm and visible venous collaterals at the neck, shoulder, and chest. Compression ultrasonography reveals a patent left distal subclavian vein, but there is an abnormal Doppler-flow pattern suggestive of a more proximal thrombosis. How should this case be further evaluated and managed? Copyright © 2011 Massachusetts Medical Society. Source


The regulation of genetically engineered crops, in Europe and within the legislation of the Cartagena biosafety protocol is built on false premises: The claim was (and unfortunately still is) that there is a basic difference between conventional and transgenic crops, this despite the fact that this has been rejected on scientifically solid grounds since many years. This contribution collects some major arguments for a fresh look at regulation of transgenic crops, they are in their molecular processes of creation not basically different from conventional crops, which are based in their breeding methods on natural, sometimes enhanced mutation. But the fascination and euphoria of the discoveries in molecular biology and the new perspectives in plant breeding in the sixties and seventies led to the wrong focus on transgenic plants alone. In a collective framing process the initial biosafety debates focused on the novelty of the process of transgenesis. When early debates on the risk assessment merged into legislative decisions, this wrong focus on transgenesis alone seemed uncontested. The process-focused view was also fostered by a conglomerate of concerned scientists and biotechnology companies, both with a vested interest to at least tolerate the rise of the safety threshold to secure research money and to discourage competitors of all kinds. Policy minded people and opponent activists without deeper insight in the molecular science agreed to those efforts without much resistance. It is interesting to realize, that the focus on processes was uncontested by a majority of regulators, this despite of serious early warnings from important authorities in science, mainly of US origin. It is time to change the regulation of genetically modified (GM) crops toward a more science based process agnostic legislation. Although this article concentrates on the critique of the process-oriented regulation, including some details about the history behind, there should be no misunderstanding that there are other important factors responsible for the failure of this kind of process-oriented regulation, most importantly: the predominance of politics in the decision making processes combined with the lack of serious scientific debates on regulatory matters within the European Union and also in the Cartagena system, the obscure and much too complex decision making structures within the EU, and the active, professional, negative and intimidating role of fundamental opposition against GM crops on all levels dealing with flawed science, often declared as better parallel science published by 'independent' scientists. © 2013 Elsevier B.V. Source


Euzen R.,Ecole Polytechnique Federale de Lausanne | Reymond J.-L.,University of Bern
Molecular BioSystems | Year: 2011

Glycodendrimers, such as glycoclusters and glycopolymers, are known to be very useful molecules to probe carbohydrate-lectin interactions. Herein, new second generation glycopeptide dendrimers (G2a-f) presenting a l-lysine-based (Lys) tetraantennary scaffold, four external thiomannosyl residues and, in the case of compounds G2b-f, four copies of a variable amino acid (X 1) were synthesized and used as Concanavalin A (Con A) inhibitors. An increased-sensitivity Enzyme-Linked Lectin Assay (ELLA) was also developed to evaluate precisely the relative strength of the glycodendrimer-lectin interactions. Glycopeptide dendrimer G2e, for which l-tyrosine (Tyr) was used as a variable amino acid, led to optimal inhibition properties (IC 50 = 52 μM). Additionally, glycopeptide dendrimers G2g-k built on a scaffold displaying four external Tyr and more internally, four copies of a variable amino acid (X 2) were synthesized and involved in the mentioned ELLA. Even if no strong improvement was observed, such structural modulations could also modify the inhibition properties of glycopeptide dendrimers. Finally, mono-, di- and octavalent analogs of G2e, noticed, respectively, G0, G1 and G3, were produced and assayed. Multivalency then appeared as a key feature since inhibition properties of these glycoconjuguates increased with the number of carbohydrate moieties and a relatively strong cluster effect was obtained for the octavalent derivative G3 (IC 50 = 2.9 μM). © The Royal Society of Chemistry. Source


Lombardo U.,University of Bern
Earth Surface Dynamics | Year: 2014

The paper examines the role of neotectonic activity in the evolution of the landscape in southern Amazonia during the Holocene. It uses both new and published data based on the analysis of remote sensing imagery and extensive field work in the Llanos de Moxos, Bolivian Amazon. The study of the region's modern and palaeorivers, ria lakes, palaeosols and topography provides a strong case in favour of the thesis that the northern part of the Llanos de Moxos constitutes the southern margin of the Fitzcarrald Arch and that it has experienced uplift during the Holocene. The paper assesses the extent and timing of the neotectonic activity in light of the new data and reconstructs the evolution of the landscape since the late Pleistocene. The evidence suggests that at least two uplift events took place: a first uplift in the late Pleistocene, which caused the formation of Lake Oceano, and a second uplift during the mid-Holocene, which formed Lake Rogaguado. These two uplifts appear to be linked to the knickpoints observed close to the towns of Guayaramerín and Puerto Siles respectively. The backwater effect due to these uplifts transformed the region's major rivers in seasonal ria lakes, causing the deposition of thick organic clay layers along the Beni, Mamoré and Madre de Dios river banks. I argue that neotectonic episodes could have dramatically changed the drainage of the Llanos de Moxos, determining its flooding regime, soil properties and forest-savannah ecotone. These results stress the need for geomorphologists, palaeo-ecologists and archaeologists to take into account neotectonics when reconstructing the region's past. © 2014 Author(s). Source


BACKGROUND:: Gastrointestinal (GI) complications often delay recovery after radical cystectomy with urinary diversion. The authors investigated if perioperative administration of a potassium-enriched, chloride-depleted 5% glucose solution (G5K) accelerates recovery of GI function. METHODS:: This randomized, parallel-group, single-center double-blind trial included 44 consecutive patients undergoing radical cystectomy and pelvic lymph node dissection with urinary diversion. Patients were randomized to receive either a G5K (G5K group) solution or a Ringer’s maleate solution (control group). Fluid management aimed for a zero fluid balance. Primary endpoint was time to first defecation. Secondary endpoints were time to normal GI function, need for electrolyte substitution, and renal dysfunction. RESULTS:: Time to first defecation was not significantly different between groups (G5K group, 93 h [19 to 168 h] and control group, 120 h [43 to 241 h]); estimator of the group difference, −16 (95% CI, −38 to 6); P = 0.173. Return of normal GI function occurred faster in the G5K group than in the control group (median, 138 h [range, 54 to 262 h] vs. 169 h [108 to 318 h]); estimator of the group difference, −38 (95% CI, −74 to −12); P = 0.004. Potassium and magnesium were less frequently substituted in the G5K group (13.6 vs. 54.5% [P = 0.010] and 18.2 vs. 77.3% [P < 0.001]), respectively. The incidence of renal dysfunction (Risk, Injury, Failure, Loss and End-stage kidney disease stage “risk”) at discharge was 9.1% in the G5K group and 4.5% in the control group; P = 1.000. CONCLUSIONS:: Perioperative administration of a G5K did not enhance first defecation, but may accelerate recovery of normal GI function, and reduces potassium and magnesium substitution after radical cystectomy and urinary diversion. Copyright © by 2016, the American Society of Anesthesiologists, Inc. Wolters Kluwer Health, Inc. All Rights Reserved. Source


Jakob S.M.,University of Bern
Current Opinion in Critical Care | Year: 2010

Purpose of review: Mechanical ventilation is a cornerstone of ICU treatment. Because of its interaction with blood flow and intra-abdominal pressure, mechanical ventilation has the potential to alter hepato-splanchnic perfusion, abdominal organ function and thereby outcome of the most critically ill patients. Recent findings: Mechanical ventilation can alter hepato-splanchnic perfusion, but the effects are minimal (with moderate inspiratory pressures, tidal volumes, and positive end-expiratory pressure levels) or variable (with high ones). Routine nursing procedures may cause repeated episodes of inadequate hepato-splanchnic perfusion in critically ill patients, but an association between perfusion and multiple organ dysfunction cannot yet be determined. Clinical research continues to be challenging as a result of difficulties in measuring hepato-splanchnic blood flow at the bedside. Summary: Mechanical ventilation and attempts to improve oxygenation such as intratracheal suctioning and recruitment maneuvers, may have harmful consequences in patients with already limited cardiovascular reserves or deteriorated intestinal perfusion. Due to difficulties in assessing hepato-splanchnic perfusion, such effects are often not detected. © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins. Source


Margalida A.,University of Bern | Colomer M.A.,University of Lleida
Scientific Reports | Year: 2012

Biodiversity losses are increasing as a consequence of negative anthropogenic effects on ecosystem dynamics. However, the magnitude and complexity of these effects may still be greatly underestimated. Most Old World vultures have experienced rapid population declines in recent years. In Europe, their immediate conservation depends on changes in health regulations affecting the availability of food provided by domestic carcasses. Information is lacking on the effects of a hypothetical food shortage on the population dynamics of vultures, and is necessary to assess the potential impacts of policy decisions on future changes in biodiversity and ecosystem services. A novel computational model (P-systems) was used to model these effects, forecasting a rapid decline in the Eurasian griffon vulture (Gyps fulvus). By contrast, vulture species with greater plasticity in their dietary range appeared less sensitive to declining food availability. This study extends our understanding of vulture ecosystem services, which have social and economic implications. Source


Schneider H.,University of Bern | Miller R.K.,University of Rochester
International Journal of Developmental Biology | Year: 2010

The human placenta is required to be the anchor, the conduit and the controller during pregnancy. The survival of the baby and its associated placenta is dependent upon the placenta shielding the embryo/fetus from harm, e.g., autoimmune disease - thrombophilia, antiphospholipid syndrome or infections, while simultaneously providing for the passage of critical nutrients (e.g., amino acids, vitamins) and beneficial immunoglobulins. In a number of instances, the movements of macromolecules into and through the placenta can result in the passage of the intact molecules into the fetal circulation or in the case of proteins - catabolism to amino acids which are utilized by the placenta and the fetus for continued growth and development. The transfer of two such macromolecules, immunoglobulin G (IgG) and vitamin B12 (cyanocobalamin or B12), are examined as to the unique receptor-mediated transfer capability of the human placenta, its transfer specificity as related to specific receptors and the role of endogeneous placental proteins (trancobalamins) in facilitating the recognition and transport of specifically B12. Brief comparisons will be made to other animal species and the differences in specific organ transfer capabilities. © 2009 UBC Press. Source


Tutuian R.,University of Bern
Current Opinion in Gastroenterology | Year: 2014

PURPOSE OF REVIEW: Obesity and gastroesophageal reflux disease (GERD) are two prevalent conditions with important impact on health resource utilization around the world. Obesity is a known risk factor in the pathogenesis of GERD. When conservative measures fail, bariatric surgery remains the only option to lose weight and correct obesity-related comorbidities. The influence of bariatric surgery on GERD depends on which bariatric intervention is used. RECENT FINDINGS: Recent studies indicate that laparoscopic gastric banding and laparoscopic sleeve gastrectomy have little influence on preexisting GERD symptoms and findings, but some patients may develop GERD after laparoscopic sleeve gastrectomy. A number of studies have documented that laparoscopic Roux-en-Y gastric bypass improves GERD symptoms and findings, making it the preferred procedure for morbid obese patients with concomitant GERD. SUMMARY: Current findings provide good arguments for searching for and treating GERD in patients scheduled to undergo bariatric surgery. The presence of GERD might represent a relative contraindication for sleeve gastrectomy or gastric banding or both. Gastric bypass might be the procedure of choice in morbid obese patients with GERD symptoms or findings or both. © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins. Source


Valent P.,Medical University of Vienna | Dahinden C.A.,University of Bern
Current Opinion in Hematology | Year: 2010

Purpose of review: It is well appreciated that differentiation, growth, and function of basophils are regulated by a network of cytokines, and that these cells express a unique composition of surface receptors including interleukin-binding sites. In the current article, most recent discoveries around cytokine regulation of basophils are discussed and compared with previous data. Recent findings: Confirming previous studies, the most potent growth factor for basophils remains interleukin (IL)-3, followed by granulocyte-macrophage colony-stimulating factor and IL-5. These cytokines also act on mature basophils through specific receptors, thereby mediating adhesion, migration, and releasability. Other molecules regulating basophil function are chemokines such as IL-8 or eotaxin and IL-33. Especially IL-33 has been described as a novel basophil regulator. All cytokines act on basophils via specific receptors and signal transduction pathways. The present article provides a summary of our knowledge on cytokine regulation of basophils and receptor expression, with emphasis on most recent developments in the field. Summary: Basophil regulation by cytokines in health and disease may be a more complex process than has been considered previously. Some of the affected cytokine cascades, receptors, and signal transduction molecules may serve as targets of therapy in 'basophil activation disorders' in the future. © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins. Source


The phosphoinositide 3-kinase (PI3K) pathway plays a crucial role in cell proliferation and survival and is frequently activated by genetic and epigenetic alterations in human cancer. An arsenal of pharmacological inhibitors of key signaling enzymes in this pathway, including class IA PI3K isoforms, has been developed in the past decade and several compounds have entered clinical testing in cancer patients. The PIK3CA/ p110a isoform is the most studied enzyme of the family and a validated cancer target. The induction of autophagy by PI3K pathway inhibitors has been documented in various cancers, although a clear picture about the significance of this phenomenon is still missing, especially in the in vivo situation. A better understanding of the contribution of autophagy to the action of PI3K inhibitors on tumors cells is important, since it may limit or enhance the action of these compounds, depending on the cellular context. © 2013 Landes Bioscience. Source


Gnann H.,Albert Ludwigs University of Freiburg | Weinmann W.,University of Bern | Thierauf A.,Albert Ludwigs University of Freiburg
Alcoholism: Clinical and Experimental Research | Year: 2012

Background: For almost 30 years, phosphatidylethanol (PEth) has been known as a direct marker of alcohol consumption. This marker stands for consumption in high amounts and for a longer time period, but it has been also detected after 1 high single intake of ethanol (EtOH). The aim of this study was to obtain further information about the formation and elimination of PEth 16:0/18:1 by simulating extensive drinking. Methods: After 3 weeks of alcohol abstinence, 11 test persons drank an amount of EtOH leading to an estimated blood ethanol concentration of 1 g/kg on each of 5 successive days. After the drinking episode, they stayed abstinent for 16 days with regular blood sampling. PEth 16:0/18:1 analysis was performed using liquid chromatography-tandem mass spectrometry (high-performance liquid chromatography 1100 system and QTrap 2000 triple quadrupole linear ion trap mass spectrometer. Values of blood alcohol were obtained using a standardized method with headspace gas chromatography flame ionization detector. Results: Maximum measured concentrations of EtOH were 0.99 to 1.83 g/kg (mean 1.32 g/kg). These values were reached 1 to 3 hours after the start of drinking (mean 1.9 hours). For comparison, 10 of 11 volunteers had detectable PEth 16:0/18:1 values 1 hour after the start of drinking, ranging from 45 to 138 ng/ml PEth 16:0/18:1. Over the following days, concentrations of PEth 16:0/18:1 increased continuously and reached the maximum concentrations of 74 to 237 ng/ml between days 3 and 6. Conclusions: This drinking experiment led to measurable PEth concentrations. However, PEth 16:0/18:1 concentrations stayed rather low compared with those of alcohol abusers from previous studies. © 2012 by the Research Society on Alcoholism. Source


Willenberg T.,University of Bern
Reviews in Vascular Medicine | Year: 2014

Main current treatment options for varicose veins will be commented. Minimal invasive modalities have been established recently, conventional surgery is not the standard treatment anymore. The armamentarium to treat varicose veins has enriched enormously, different treatment options should be tailored for the individual patient. Representative cases will be discussed. © 2014 Elsevier GmbH. Source


Steinlin M.,University of Bern
Handbook of Clinical Neurology | Year: 2013

Cerebrovascular problems in childhood include diverse problems of vascular supply to the brain and occur with an overall frequency of from 5 to 8/100. 000 children/year. Signs and symptoms at manifestation are manifold. They depend not only on localization of the infarction but also on age at injury and specific risk factors. Acute arterial ischemic insult in neonates is oligosymptomatic (short-lasting seizures); hemiparesis is the most common symptom in children. Risk factors are multiple for both neonates and children, with more thromboembolic events in neonates and (infection-related) vasculopathies or cardiac problems in children. MRI (diffusion weighted) is the golden standard for diagnosis. In the absence of evidence for treatment in both groups, guidelines suggest use of platelet aggregation. There are some special indications for anticoagulation. Thrombolysis should be evaluated. Two-thirds of children and neonates face lifelong neurological and neuropsychological problems. Spinal artery ischemia presents with acute spinal symptoms, mostly paraplegia. Risk factors and prognosis are similar to cerebral insults. Sinus venous thromboses are significantly less common. Provoking factors in newborns are mainly neonatal problems, and in children infections, especially in the ENT region. For diagnosis the delta sign in CT is less sensitive than MR/MR venography. In the absence of any evidence, LMWH or heparinization for 3-6 months are recommended. Prognosis is better in children than in neonates. Deep vein thrombosis and/or young age worsen the outcome. © 2013 Elsevier B.V. Source


Accurate estimation of aboveground biomass and carbon stock has gained importance in the context of the United Nations Framework Convention on Climate Change (UNFCCC) and the Kyoto Protocol. In order to develop improved forest stratum-specific aboveground biomass and carbon estimation models for humid rainforest in northeast Madagascar, this study analyzed texture measures derived from WorldView-2 satellite data. A forest inventory was conducted to develop stratum-specific allometric equations for dry biomass. On this basis, carbon was calculated by applying a conversion factor. After satellite data preprocessing, vegetation indices, principal components, and texture measures were calculated. The strength of their relationships with the stratum-specific plot data was analyzed using Pearson's correlation. Biomass and carbon estimation models were developed by performing stepwise multiple linear regression. Pearson's correlation coefficients revealed that (a) texture measures correlated more with biomass and carbon than spectral parameters, and (b) correlations were stronger for degraded forest than for non-degraded forest. For degraded forest, the texture measures of Correlation, Angular Second Moment, and Contrast, derived from the red band, contributed to the best estimation model, which explained 84% of the variability in the field data (relative RMSE = 6.8%). For non-degraded forest, the vegetation index EVI and the texture measures of Variance, Mean, and Correlation, derived from the newly introduced coastal blue band, both NIR bands, and the red band, contributed to the best model, which explained 81% of the variability in the field data (relative RMSE = 11.8%). These results indicate that estimation of tropical rainforest biomass/carbon, based on very high resolution satellite data, can be improved by (a) developing and applying forest stratum-specific models, and (b) including textural information in addition to spectral information. © 2012 by the authors. Source


The bacterial phosphoenolpyruvate (PEP): sugar phosphotransferase system (PTS) mediates the uptake and phosphorylation of carbohydrates, and is involved in signal transduction. It comprises two general phosphotransferase proteins (EI and HPr) and a - species dependent - variable number of sugar-specific enzyme II complexes (IIA, IIB, IIC). EI and HPr transfer phosphoryl groups from PEP to the IIA units. IIA and IIB sequentially transfer phosphates to the sugar, which is translocated by the IIC unit. The ratio of phosphorylated to non-phosphorylated IIA and IIB varies with transport activity, and the phosphorylation state of some of the IIA and IIB serves as signal input for regulation of catabolite repression, intermediate metabolism, gene expression and chemotaxis in response to the availability of carbohydrates and PEP (glycolytic activity). PTS occur in about one-third of all eubacteria and in a few archaebacteria but not in animals and plants. Uniqueness and pleiotropic function make the PTS a potential target for anti-infectives. The PTS transporter for mannose is utilized as a gate for the penetration of bacteriophage lambda DNA across, and insertion of certain bacteriocins (small antimicrobial peptides) into the inner membrane. The PTS of Escherichia coli is in the focus of this review, but occasionally comparisons with other species are made. The topics are: History; Modular design of the E. coli PTS; Structure function and catalytic mechanism of the protein modules; Regulation of and by the PTS; The PTS in pathogenicity and virulence; Computational models; Metabolic engineering. © 2012 Iranian Chemical Society. Source


Allen M.R.,University of Oxford | Stocker T.F.,University of Bern | Stocker T.F.,Oeschger Center for Climate Change Research
Nature Climate Change | Year: 2014

Recent downward revisions in the climate response to rising CO2 levels, and opportunities for reducing non-CO2 climate warming, have both been cited as evidence that the case for reducing CO2 emissions is less urgent than previously thought. Evaluating the impact of delay is complicated by the fact that CO2 emissions accumulate over time, so what happens after they peak is as relevant for long-term warming as the size and timing of the peak itself. Previous discussions have focused on how the rate of reduction required to meet any given temperature target rises asymptotically the later the emissions peak. Here we focus on a complementary question: how fast is peak CO2 -induced warming increasing while mitigation is delayed, assuming no increase in rates of reduction after the emissions peak? We show that this peak-committed warming is increasing at the same rate as cumulative CO2 emissions, about 2% per year, much faster than observed warming, independent of the climate response. © 2014 Macmillan Publishers Limited. All rights reserved. Source


Asphaug E.,Arizona State University | Asphaug E.,University of California at Santa Cruz | Reufer A.,University of Bern
Icarus | Year: 2013

Saturn is orbited by a half dozen ice rich middle-sized moons (MSMs) of diverse geology and composition. These comprise ∼4.4% of Saturn's satellite mass; the rest is Titan, more massive per planet than Jupiter's satellites combined. Jupiter has no MSMs. Disk-based models to explain these differences exist, but have various challenges and assumptions. We introduce the hypothesis that Saturn originally had a 'galilean' system of moons comparable to Jupiter's, that collided and merged, ultimately forming Titan. Mergers liberate ice-rich spiral arms in our simulations, that self-gravitate into escaping clumps resembling Saturn's MSMs in size and compositional diversity. We reason that MSMs were spawned in a few such collisional mergers around Saturn, while Jupiter's original satellites stayed locked in resonance. © 2012 Elsevier Inc. Source


Gaar D.,University of Bern | Preusser F.,University of Stockholm
Quaternary Geochronology | Year: 2012

Remains of at least two individuals of woolly mammoths (Mammuthus primigenius) were discovered after blastings in a limestone quarry located on the southern slope of the Jura Mountains, northern Switzerland. During the subsequent excavation two blocks were taken for luminescence dating from the sediment surrounding the remains; the deposits are interpreted to represent the filling of a karst hole. Luminescence dates on the polymineral and purified quartz fine grain fraction are compared to those obtained for single grains of quartz and small aliquots of quartz as well as feldspar coarse grains. All approaches give ages consistent within the dating uncertainties and are interpreted to prove the robustness of the dating results. The age of the sediment of ca. 63 ka indicates deposition during Marine Isotope Stage (MIS) 4, thus, during a time when Switzerland experienced rather cold climatic conditions. These are some of the oldest numerically dated woolly mammoth remains of Europe. © 2012 Elsevier B.V. Source


Stocker T.F.,University of Bern
Science | Year: 2015

The most recent comprehensive assessment carried out by the Intergovernmental Panel on Climate Change has concluded that "Human influence on the climate system is clear," a headline statement that was approved by all governments in consensus. This influence will have long-lasting consequences for ecosystems, and the resulting impacts will continue to be felt millennia from now. Although the terrestrial impacts of climate change are readily apparent now and have received widespread public attention, the effects of climate change on the oceans have been relatively invisible. However, the world ocean provides a number of crucial services that are of global significance, all of which come with an increasing price caused by human activities. This needs to be taken into account when considering adaptation to and mitigation of anthropogenic climate change. Source


Heverhagen J.T.,University of Bern | Krombach G.A.,Justus Liebig University | Gizewski E.,Innsbruck Medical University
RoFo Fortschritte auf dem Gebiet der Rontgenstrahlen und der Bildgebenden Verfahren | Year: 2014

Nephrogenic systemic fibrosis (NSF) is a serious, sometimes fatal disease. Findings in recent years have shown that a causal association between gadolinium containing contrast media and NSF is most likely. Therefore, the regulatory authorities have issued guidelines on the use of gadolinium-containing contrast media which have reduced the number of new cases of NSF to almost zero. However, it is for precisely this reason that the greatest care must still be taken to ensure that these guidelines are complied with. The most important factors are renal function, the quantity of gadolinium administered and coexisting diseases such as inflammation. All of these factors crucially influence the quantity of gadolinium released from the chelat in the body. This free gadolinium is thought to be the trigger for NSF. Other important factors are the stability of the gadolinium complex and furthermore the route of its elimination from the body. Partial elimination via the liver might be an additional protective mechanism. In conclusion, despite the NSF risk, contrast-enhanced MRI is a safe diagnostic procedure which can be used reliably and safely even in patients with severe renal failure, and does not necessarily have to be replaced by other methods. Key Points: • Despite the inherent risk of NSF, a MR investigation must not be denied to a patient provided there are sufficient indications and the possible benefits outweigh the risk. • The risk of NSF can be minimized by adhering to the federal guidelines and using the minimal necessary Gd dose. • It is recommended to measure the eGFR in all patients prior to the administration of a Gd-chelate. However, it is mandatory only when using agents of the high risk group. • Gd-chelates should classified into two risk classes. No differences should be made between low and medium risk agents. • Partial elimination of the agent by the liver may have a protective effect against NSF. Citation Format: • Heverhagen JT, Krombach GA, Gizewski E. Application of Extrcellular Gadolinium-based MRI Contrast Agents and the Risk of Nephrogenic Systemic Fibrosis. Fortschr Röntgenstr 2014; 186: 661 669 © 2014 Georg Thieme Verlag KG Stuttgart New York. Source


Zehnder P.,University of Bern | Gill I.S.,University of Southern California
Current Opinion in Urology | Year: 2011

PURPOSE OF REVIEW: To provide insight into the recently published cost comparisons in the context of open, laparoscopic, and robotic-assisted laparoscopic radical cystectomy and to demonstrate the complexity of such economic analyses. RECENT FINDINGS: Most economic evaluations are from a hospital perspective and summarize short-term perioperative therapeutic costs. However, the contributing factors (e.g. study design, included variables, robotic amortization plan, supply contract, surgical volume, surgeons' experience, etc.) vary substantially between the institutions. In addition, a real cost-effective analysis considering cost per quality-adjusted life-year gained is not feasible because of the lack of long-term oncologic and functional outcome data with the robotic procedure. On the basis of a modeled cost analysis using results from published series, robotic-assisted cystectomy was - with few exceptions - found to be more expensive when compared with the open approach. Immediate costs are affected most by operative time, followed by length of hospital stay, robotic supply, case volume, robotic cost, and transfusion rate. Any complication substantially impacts overall costs. SUMMARY: Economic cost evaluations are complex analyses influenced by numerous factors that hardly allow an interinstitutional comparison. Robotic-assisted cystectomy is constantly refined with many institutions being somewhere on their learning curve. Transparent reports of oncologic and functional outcome data from centers of expertise applying standardized methods will help to properly analyze the real long-term benefits of robotic surgery and successor technologies and prevent us from becoming slaves of successful marketing strategies. © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins. Source


Skin tumours, in particular squamous-cell carcinomas (SCC), are the most common malignant conditions developing in transplant recipients. The aim of this study is to investigate the frequency and type of skin cancer in patients receiving immunosuppressive therapy after organ transplantation. Multivariate logistic regression analysis was performed on data of 243 renal transplant patients who attended the dermatology outpatient clinic for the first time after transplantation in the period January 2002-October 2005. We found an increased risk of actinic keratosis (AK) and SCC in renal transplant recipients with a basal cell carcinoma (BCC) / SCC ratio of 1:7. Older patients had AK more frequently (odds ratio [OR] 1.11, 95% confidence interval [CI] 1.06-1.15; p <0.0001) and SCC (OR 1.14, CI 1.07-1.22; p <0.0001) than younger patients. Men had AK (OR 0.19, CI 0.08-0.45; p = 0.0002) and SCC (OR 0.25, CI 0.07-0.89; p = 0.0332) more frequently than women. The duration of immunosuppressive therapy correlated significantly with the numbers of AKs (OR 1.15, CI 1.08-1.24; p <0.0001) and SCCs (OR 1.16, CI 1.05-1.28; p = 0.0025), and patients with fair skin had more AKs (OR 0.31, CI 0.14-1.24; p <0.0001) and SCCs (OR 0.11, CI 0.02-0.52; p = 0.0054) than darker skinned patients. We could not identify any specific immunosuppressive drug as a distinct risk factor for AK or non-melanoma skin cancer (NMSC). Skin cancers are increased in the renal transplant population. Main risk factors for skin cancers are fair skin type and long duration of immunosuppressive therapy. A follow-up programme is necessary for early detection of skin cancer and precancerous conditions. Preventive strategies should include specialist dermatological monitoring and self-examination. Source


Jenkins T.,Imperial College London | Jenkins T.,University of Bern | Owens I.P.F.,Imperial College London
Molecular Ecology | Year: 2011

Relationships between hosts and parasites represent complex co-evolving systems that can vary both temporally and spatially. This variation may result in different phylogeographic outcomes, ranging from highly geographically structured parasite populations comprised of specialist lineages that are locally abundant but have restricted global occupancy to geographically unstructured parasite populations consisting of widespread parasites. Here, we present results from a large biogeographic study of the Leucocytozoon blood parasites of two nonmigrant bird species, conducted at nine sites across Europe. The aim was to determine whether the parasite lineages of the two hosts were phylogeographically structured across Europe. Employing molecular methods, we found a large diversity of parasites, and although overall prevalence varied greatly, the parasites were not genetically structured. Several measures of local parasite abundance were associated with the number of sites that the lineage occurred in, which is consistent with the macroecological phenomenon of the abundance-occupancy relationship. Taken together, our results show that parasite dispersal is somewhat uncoupled to that of the host in this system: we suggest that broad host and/or vector preference may play an important role in determining the distribution of these parasites and in affecting host-parasite coevolution in this system. © 2011 Blackwell Publishing Ltd. Source


Heng K.,University of Bern | Demory B.-O.,Massachusetts Institute of Technology
Astrophysical Journal | Year: 2013

Unlike previously explored relationships between the properties of hot Jovian atmospheres, the geometric albedo and the incident stellar flux do not exhibit a clear correlation, as revealed by our re-analysis of Q0-Q14 Kepler data. If the albedo is primarily associated with the presence of clouds in these irradiated atmospheres, a holistic modeling approach needs to relate the following properties: the strength of stellar irradiation (and hence the strength and depth of atmospheric circulation), the geometric albedo (which controls both the fraction of starlight absorbed and the pressure level at which it is predominantly absorbed), and the properties of the embedded cloud particles (which determine the albedo). The anticipated diversity in cloud properties renders any correlation between the geometric albedo and the stellar flux weak and characterized by considerable scatter. In the limit of vertically uniform populations of scatterers and absorbers, we use an analytical model and scaling relations to relate the temperature-pressure profile of an irradiated atmosphere and the photon deposition layer and to estimate whether a cloud particle will be lofted by atmospheric circulation. We derive an analytical formula for computing the albedo spectrum in terms of the cloud properties, which we compare to the measured albedo spectrum of HD 189733b by Evans et al. Furthermore, we show that whether an optical phase curve is flat or sinusoidal depends on whether the particles are small or large as defined by the Knudsen number. This may be an explanation for why Kepler-7b exhibits evidence for the longitudinal variation in abundance of condensates, while Kepler-12b shows no evidence for the presence of condensates despite the incident stellar flux being similar for both exoplanets. We include an "observer's cookbook" for deciphering various scenarios associated with the optical phase curve, the peak offset of the infrared phase curve, and the geometric albedo. © 2013. The American Astronomical Society. All rights reserved.. Source


Khattab A.A.,University of Bern
Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions | Year: 2012

The authors report on the use of 5 French diagnostic catheters to deliver a stent-on-a-wire system during a double vessel coronary intervention. Copyright © 2011 Wiley Periodicals, Inc. Source


Zembic A.,Academic Center for Dentistry Amsterdam | Zembic A.,University of Bern | Wismeijer D.,Academic Center for Dentistry Amsterdam
Clinical Oral Implants Research | Year: 2014

Objective: The aim of the present prospective clinical study was to compare patient-reported outcomes for maxillary conventional dentures and maxillary implant-supported dentures. Material and methods: Twenty-one patients (6 women and 15 men) being edentulous in the maxilla and encountering problems with their existing dentures were included. Twelve patients (4 women and 8 men) received a new set of conventional dentures, due to insufficient dentures. In nine patients (2 women and 7 men), the existing dentures were adjusted by means of relining or rebasing. All patients received implant-supported dentures on two retentive anchors. In total, 42 implants were inserted in the anterior maxilla. The participants rated their satisfaction on their existing conventional dentures, 2 months after insertion of new conventional dentures and 2 months after insertion of implant-supported dentures. Thereby, patients responded to questionnaires capturing the oral health impact profile (OHIP) using visual analog scales. Seven domains (functional limitation, physical pain, psychological discomfort, physical, psychological and social disability and handicap) were assessed. Higher scores implied poorer patient satisfaction. In addition, the questionnaire involved the evaluation of cleaning ability, general satisfaction, speech, comfort, esthetics, stability, and chewing ability. Higher scores implied higher patient satisfaction. Results: Patient satisfaction significantly increased for implant-supported dentures compared with old dentures in all seven OHIP subgroups, as well as for cleaning ability, general satisfaction, ability to speak, comfort, esthetics, and stability (P < 0.05). The comparison of new conventional dentures and implant-supported dentures revealed a statistically significantly increased satisfaction for functional limitation (difference of 33.2 mm), psychological discomfort (difference of 36.7 mm), physical disability (difference of 36.3 mm), and social disability (difference of 23.5 mm), (P < 0.05). Additionally, general satisfaction, chewing ability, speech, and stability significantly improved in implant-supported dentures (P < 0.05). Conclusions: Within the limits of this study, maxillary dentures retained by two implants provided some significant short-term improvements over conventional dentures in oral- and health-related quality of life. © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd. Source


da Costa B.R.,University of Bern
Cochrane database of systematic reviews (Online) | Year: 2012

Osteoarthritis is a chronic joint disease that involves degeneration of articular cartilage. Pre-clinical data suggest that doxycycline might act as a disease-modifying agent for the treatment of osteoarthritis, with the potential to slow cartilage degeneration. This is an update of a Cochrane review first published in 2009. To examine the effects of doxycycline compared with placebo or no intervention on pain and function in people with osteoarthritis of the hip or knee. We searched CENTRAL (The Cochrane Library 2008, issue 3), MEDLINE, EMBASE and CINAHL up to 28 July 2008, with an update performed at 16 March 2012. In addition, we checked conference proceedings, reference lists, and contacted authors. We included studies if they were randomised or quasi-randomised controlled trials that compared doxycycline at any dosage and any formulation with placebo or no intervention in people with osteoarthritis of the knee or hip. We extracted data in duplicate. We contacted investigators to obtain missing outcome information. We calculated differences in means at follow-up between experimental and control groups for continuous outcomes and risk ratios (RR) for binary outcomes. We identified one additional trial (232 participants) and included two trials (663 participants) in this update. The methodological quality and the quality of reporting were considered moderate. At end of treatment, clinical outcomes were similar between the two treatment groups, with an effect size of -0.05 (95% confidence interval (CI) -0.22 to 0.13), corresponding to a difference in pain scores between doxycycline and control of -0.1 cm (95% CI -0.6 to 0.3 cm) on a 10-cm visual analogue scale, or 32% versus 29% improvement from baseline (difference 3%; 95% CI -5% to 10%). The effect size for function was -0.07 (95% CI -0.25 to 0.10), corresponding to a difference between doxycycline and control of -0.2 (95% CI -0.5 to 0.2) on the Western Ontario and McMaster Universities Arthritis Index (WOMAC) disability subscale with a range of 0 to 10, or 24% versus 21% improvement (difference 3%; 95% CI -3% to 10%). The difference in changes in minimum joint space narrowing assessed in one trial was in favour of doxycycline (-0.15 mm; 95% CI -0.28 to -0.02 mm), which corresponds to a small effect size of -0.23 standard deviation units (95% CI -0.44 to -0.02). More participants withdrew from the doxycycline group compared with placebo due to adverse events (RR 2.28; 95% CI 1.06 to 4.90). There was no evidence that participants in the doxycycline group experienced more serious adverse events than those in the placebo group, but the estimate was imprecise (RR 1.07; 95% CI 0.68 to 1.68). In this update, the strength of evidence for effectiveness outcomes was improved from low to moderate and we confirmed that the symptomatic benefit of doxycycline is minimal to non-existent, while the small benefit in terms of joint space narrowing is of questionable clinical relevance and outweighed by safety problems. The CIs of the summary estimates now exclude any clinically relevant difference in improvement of symptoms and the small benefit in terms of joint space narrowing does not outweigh the harms. Source


Does intrauterine application of diluted seminal plasma (SP) at the time of ovum pick-up improve the pregnancy rate by ≥14% in IVF treatment? Intrauterine instillation of diluted SP at the time of ovum pick-up is unlikely to increase the pregnancy rate by ≥14% in IVF. SP modulates endometrial function, and sexual intercourse around the time of embryo transfer has been suggested to increase the likelihood of pregnancy. A previous randomized double-blind pilot study demonstrated a strong trend towards increased pregnancy rates following the intracervical application of undiluted SP. As this study was not conclusive and as the finding could have been confounded by sexual intercourse, the intrauterine application of diluted SP was investigated in the present trial. A single-centre, prospective, double-blind, placebo-controlled, randomized, superiority trial on women undergoing IVF was conducted from April 2007 until February 2012 at the University Department of Gynaecological Endocrinology and Reproductive Medicine, Heidelberg, Germany. The study was powered to detect an 14% increase in the clinical pregnancy rate and two sequential tests were planned using the Pocock spending function. At the first interim analysis, 279 women had been randomly assigned to intrauterine diluted SP (20% SP in saline from the patients' partner) (n = 138) or placebo (n = 141) at the time of ovum pick-up. The clinical pregnancy rate per randomized patient was 37/138 (26.8%) in the SP group and 41/141 (29.1%) in the placebo group (difference: -2.3%, 95% confidence interval of the difference: -12.7 to +8.2%; P = 0.69). The live birth rate per randomized patient was 28/138 (20.3%) in the SP group and 33/141 (23.4%) in the placebo group (difference: -3.1%, 95% confidence interval of the difference: -12.7 to +6.6%; P = 0.56). It was decided to terminate the trial due to futility at the first interim analysis, at a conditional power of 62%. The confidence interval of the difference remains wide, thus clinically relevant differences cannot reliably be excluded based on this single study. The results of this study cast doubt on the validity of the concept that SP increases endometrial receptivity and thus implantation in humans. Funding was provided by the department's own research facilities. DRKS00004615. Source


Nicolussi K.,University of Innsbruck | Schluchter C.,University of Bern
Geology | Year: 2012

Evidence for an 8.2 ka event-related advance for an Alpine glacier was missing for a long time. In the light of dendrochronological analyses for tree remains found in front of the Mont Miné Glacier, Swiss Alps, we present evidence for such an advance related to the 8.2 ka event. Calendar dates established for dozens of tree remains place this glacier advance ∼8175 yr before A.D. 2000. Therefore, this 8.2 ka advance response of the Mont Miné Glacier terminated a nearly millennial-long retreat period with a glacier always shorter than today. © 2012 Geological Society of America. Source


Tonia T.,University of Bern
Cochrane database of systematic reviews (Online) | Year: 2012

Anaemia associated with cancer and cancer therapy is an important clinical factor in the treatment of malignant diseases. Therapeutic alternatives are recombinant human erythropoiesis stimulating agents (ESAs) and red blood cell transfusions. To assess the effects of ESAs to either prevent or treat anaemia in cancer patients. This is an update of a Cochrane review first published in 2004. We searched the Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE and other databases. Searches were done for the periods 01/1985 to 12/2001 for the first review, 1/2002 to 04/2005 for the first update and to November 2011 for the current update. We also contacted experts in the field and pharmaceutical companies. Randomised controlled trials on managing anaemia in cancer patients receiving or not receiving anti-cancer therapy that compared the use of ESAs (plus transfusion if needed). Several review authors assessed trial quality and extracted data. One review author assessed quality assessment and extracted data, a second review author checked for correctness. This update of the systematic review includes a total of 91 trials with 20,102 participants. Use of ESAs significantly reduced the relative risk of red blood cell transfusions (risk ratio (RR) 0.65; 95% confidence interval (CI) 0.62 to 0.68, 70 trials, N = 16,093). On average, participants in the ESAs group received one unit of blood less than the control group (mean difference (MD) -0.98; 95% CI -1.17 to -0.78, 19 trials, N = 4,715). Haematological response was observed more often in participants receiving ESAs (RR 3.93; 95% CI 3.10 to 3.71, 31 trials, N = 6,413). There was suggestive evidence that ESAs may improve Quality of Life (QoL). There was strong evidence that ESAs increase mortality during active study period (hazard ratio (HR) 1.17; 95% CI 1.06 to 1.29, 70 trials, N = 15,935) and some evidence that ESAs decrease overall survival (HR 1.05; 95% CI 1.00 to 1.11, 78 trials, N = 19,003). The risk ratio for thromboembolic complications was increased in patients receiving ESAs compared to controls (RR 1.52, 95% CI 1.34 to 1.74; 57 trials, N = 15,498). ESAs may also increase the risk for hypertension (fixed-effect model: RR 1.30; 95% CI 1.08 to 1.56; random-effects model: RR 1.12; 95% CI 0.94 to 1.33, 31 trials, N = 7,228) and thrombocytopenia/haemorrhage (RR 1.21; 95% CI 1.04 to 1.42; 21 trials, N = 4,507). There was insufficient evidence to support an effect of ESA on tumour response (fixed-effect RR 1.02; 95% CI 0.98 to 1.06, 15 trials, N = 5,012). ESAs reduce the need for red blood cell transfusions but increase the risk for thromboembolic events and deaths. There is suggestive evidence that ESAs may improve QoL. Whether and how ESAs affects tumour control remains uncertain. The increased risk of death and thromboembolic events should be balanced against the potential benefits of ESA treatment taking into account each patient's clinical circumstances and preferences. More data are needed for the effect of these drugs on quality of life and tumour progression. Further research is needed to clarify cellular and molecular mechanisms and pathways of the effects of ESAs on thrombogenesis and their potential effects on tumour growth. Source


Neukom R.,University of Bern | Neukom R.,University of Melbourne | Gergis J.,University of Melbourne
Holocene | Year: 2012

This study presents a comprehensive assessment of high-resolution Southern Hemisphere (SH) paleoarchives covering the last 2000 years. We identified 174 monthly to annually resolved climate proxy (tree ring, coral, ice core, documentary, speleothem and sedimentary) records from the Hemisphere. We assess the interannual and decadal sensitivity of each proxy record to large-scale circulation indices from the Pacific, Indian and Southern Ocean regions over the twentieth century. We then analyse the potential of this newly expanded palaeoclimate network to collectively represent predictands (sea surface temperature, sea level pressure, surface air temperature and precipitation) commonly used in climate reconstructions. The key dynamical centres-of-action of the equatorial Indo-Pacific are well captured by the palaeoclimate network, indicating that there is considerable reconstruction potential in this region, particularly in the post AD 1600 period when a number of long coral records are available. Current spatiotemporal gaps in data coverage and regions where significant potential for future proxy collection exists are discussed. We then highlight the need for new and extended records from key dynamical regions of the Southern Hemisphere. Although large-scale climate field reconstructions for the SH are in their infancy, we report that excellent progress in the development of regional proxies now makes plausible estimates of continental- to hemispheric-scale climate variations possible. © The Author(s) 2011. Source


The established class of intravenous contrast media for magnetic resonance imaging is the gadolinium chelates, more generally referred to as the gadolinium-based contrast agents (GBCAs). These can be differentiated on the basis of stability in vivo, with safety and tolerability of the GBCAs dependent upon chemical and biologic inertness. This review discusses first the background in terms of development of these agents and safety discussions therein, and second their relative stability based both on in vitro studies and clinical observations before and including the advent of nephrogenic systemic fibrosis. This sets the stage for the subsequent focus of the review, the current knowledge regarding accumulation of gadolinium in the brain and specifically the dentate nucleus after intravenous administration of the GBCAs and differentiation among agents on this basis. The information available to date, from the initial conception of these agents in 1981 to the latest reports concerning safety, demonstrates a significant difference between the macrocyclic and linear chelates. The review concludes with a discussion of the predictable future, which includes, importantly, a reassessment of the use of the linear GBCAs or a subset thereof. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved. Source


Pasch A.,University of Bern
Current Opinion in Nephrology and Hypertension | Year: 2016

Purpose of review Blood is a biological fluid, which controls the precipitation of calcium and phosphate and transports mineral debris. This review presents and discusses the current concepts and novel assessment methods of systemic calcification propensity in blood. Recent findings Calcium and phosphate combine with calcification-inhibiting proteins, mainly fetuin-A, to form amorphous calcium phosphate-containing primary calciprotein particles (CPPs). These nanosized mineral-protein clusters undergo spontaneous transformation to secondary CPP, which contain crystalline calcium phosphate. Two recently developed methods assess complementary aspects of the calcification propensity of serum. The CPP-fetuin-A method determines the amount of sedimentable fetuin-A, whereas the T 50-Test determines the transformation time point T 50 from amorphous to crystalline CPPs in artificially supersaturated serum. Clinical studies in renal patients have already demonstrated close associations of the CPP-fetuin-A method with all-cause mortality, severity of coronary calcification and aortic stiffness, and of the T 50-Test with cardiovascular and all-cause mortality, renal graft failure and aortic stiffening. Summary Systemic calcification propensity can be assessed by two novel methods providing complementary information about the status and performance of the humoral calcification-regulating system in serum. These tests may help guide better patient care in the future with the use of more individualized therapies. © 2016 Wolters Kluwer Health, Inc. Source


Sitenko Y.A.,NASU Bogolyubov Institute for Theoretical Physics | Sitenko Y.A.,University of Bern
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

We study the influence of a background uniform magnetic field and boundary conditions on the vacuum of a quantized charged spinor matter field confined between two parallel neutral plates; the magnetic field is directed orthogonally to the plates. The admissible set of boundary conditions at the plates is determined by the requirement that the Dirac Hamiltonian operator be self-adjoint. It is shown that, in the case of a sufficiently strong magnetic field and a sufficiently large separation of the plates, the generalized Casimir force is repulsive, being independent of the choice of a boundary condition, as well as of the distance between the plates. The detection of this effect seems to be feasible in the foreseeable future. © 2015 American Physical Society. Source


Bechera T.,University of Bern | Schwartz M.D.,Harvard University
Journal of High Energy Physics | Year: 2010

The production of hard photons in hadronic collisions is studied using Soft- Collinear Effective Theory (SCET). This is the first application of SCET to a physical observable cross section involving energetic partons in more than two directions. A factorization formula is derived which involves a non-trivial interplay of the angular dependence in the hard and soft functions both quark and gluon jet functions and multiple partonic channels. The relevant hard jet and soft functions are computed to one loop and their anomalous dimensions are determined to three loops. The final resummed inclusive direct photon distribution is valid to next-to-next-to-leading logarithmic order (NNLL) one order beyond previous work. The result is improved by including non-logarithmic terms and photon isolation cuts through matching and compared to Tevatron data and to fixed order results at the Tevatron and the LHC. The resummed cross section has a significantly smaller theoretical uncertainty than the next-to-leading fixed-order result particularly at high transverse momentum. ©2010 SISSA. Source


Frick A.,University of California at Santa Cruz | Frick A.,University of Bern | Wang S.-H.,University of California at Santa Cruz
Child Development | Year: 2014

Infants' ability to mentally track the orientation of an object during a hidden rotation was investigated (N = 28 in each experiment). A toy on a turntable was fully covered and then rotated 90°. When revealed, the toy had turned with the turntable (probable event), remained at its starting orientation (improbable event in Experiment 1), or turned to the opposite side (improbable event in Experiment 2). Results demonstrated a developmental progression between 14 and 16 months of age in infants' sensitivity to spatial object relations and their ability to track the orientation of an object during hidden rotation. Experiment 3 showed that 14-month-olds' performance improved with hands-on training, highlighting the role of action experience in cognitive development. © 2013 Society for Research in Child Development, Inc. Source


Goeber V.,University of Bern
European journal of cardio-thoracic surgery : official journal of the European Association for Cardio-thoracic Surgery | Year: 2013

Adult-type Pompe's disease (glycogen storage disease type II) has rarely been shown to present with dilatative arteriopathy, suggesting potential smooth muscle involvement in addition to lysosomal glycogen deposits usually restricted to skeletal muscle tissue. We report the case of a middle-aged man under enzyme replacement therapy presenting with an exceedingly large thoracic aortic aneurysm. Surprisingly, the histological work-up of resected aortic tissue revealed changes mimicking those observed in patients with classic connective tissue diseases. Enzyme replacement therapy, in addition to musculoskeletal and pulmonary treatment for patients with Pompe's disease, may prolong survival and lead to patients presenting with vascular alterations that may pose surgical and potential diagnostic challenges in the future. Source


Villiger P.M.,University of Bern | Guillevin L.,University of Paris Descartes
Autoimmunity Reviews | Year: 2010

Microscopic polyangiitis (MPA) is a member of the family of ANCA-associated vasculitides. Its characteristic histology shows a necrotizing small vessel vasculitis with little or absent immune deposits (pauci-immune vasculitis). In Western countries MPA shows a lower prevalence than Wegener's disease, it affects more men than women and commences at the age of ≥ 50 years. The two organs most typically involved and often defining prognosis are the kidneys and the lungs. MPA may concomitantly or sequentially involve other organs such as the nervous system, the skin, the musculoskeletal system, but also the heart, the eye and the intestines. Treatment decisions should be based on severity and pattern of organ involvement and respect the five factor score (FFS). Life- or organ- threatening disease is treated with glucocorticoids and (pulse) cyclophosphamide. Plasmapheresis and i.v.immunoglobulins have been shown to be beneficial as additional measure in severe cases. If renal function is preserved, Methotrexate may be considered to induce remission, and if the FFS equals 0, remission may be induced with glucocorticoid monotherapy. Maintenance therapy is recommended with Azathioprin, mycophenolate mofetil may be used as a second line drug. Biologic agents such as monoclonal antibodies to tumor necrosis factor a and B cell depleting rituximab have been shown to bear remission-inducing quality. © 2010 Elsevier B.V. Source


Jung S.,University of Bern
Brain : a journal of neurology | Year: 2013

The goal of acute stroke treatment with intravenous thrombolysis or endovascular recanalization techniques is to rescue the penumbral tissue. Therefore, knowing the factors that influence the loss of penumbral tissue is of major interest. In this study we aimed to identify factors that determine the evolution of the penumbra in patients with proximal (M1 or M2) middle cerebral artery occlusion. Among these factors collaterals as seen on angiography were of special interest. Forty-four patients were included in this analysis. They had all received endovascular therapy and at least minimal reperfusion was achieved. Their penumbra was assessed with perfusion- and diffusion-weighted imaging. Perfusion-weighted imaging volumes were defined by circular singular value decomposition deconvolution maps (Tmax > 6 s) and results were compared with volumes obtained with non-deconvolved maps (time to peak > 4 s). Loss of penumbral volume was defined as difference of post- minus pretreatment diffusion-weighted imaging volumes and calculated in per cent of pretreatment penumbral volume. Correlations between baseline characteristics, reperfusion, collaterals, time to reperfusion and penumbral volume loss were assessed using analysis of covariance. Collaterals (P = 0.021), reperfusion (P = 0.003) and their interaction (P = 0.031) independently influenced penumbral tissue loss, but not time from magnetic resonance (P = 0.254) or from symptom onset (P = 0.360) to reperfusion. Good collaterals markedly slowed down and reduced the penumbra loss: in patients with thrombolysis in cerebral infarction 2 b-3 reperfusion and without any haemorrhage, 27% of the penumbra was lost with 8.9 ml/h with grade 0 collaterals, whereas 11% with 3.4 ml/h were lost with grade 1 collaterals. With grade 2 collaterals the penumbral volume change was -2% with -1.5 ml/h, indicating an overall diffusion-weighted imaging lesion reversal. We conclude that collaterals and reperfusion are the main factors determining loss of penumbral tissue in patients with middle cerebral artery occlusions. Collaterals markedly reduce and slow down penumbra loss. In patients with good collaterals, time to successful reperfusion accounts only for a minor fraction of penumbra loss. These results support the hypothesis that good collaterals extend the time window for acute stroke treatment. Source


Thoeny H.C.,University of Bern | Ross B.D.,University of Michigan
Journal of Magnetic Resonance Imaging | Year: 2010

An imaging biomarker that would provide for an early quantitative metric of clinical treatment response in cancer patients would provide for a paradigm shift in cancer care. Currently, nonimage based clinical outcome metrics include morphology, clinical, and laboratory parameters, however, these are obtained relatively late following treatment. Diffusion-weighted MRI (DW-MRI) holds promise for use as a cancer treatment response biomarker as it is sensitive to macromolecular and microstructural changes which can occur at the cellular level earlier than anatomical changes during therapy. Studies have shown that successful treatment of many tumor types can be detected using DW-MRI as an early increase in the apparent diffusion coefficient (ADC) values. Additionally, low pretreatment ADC values of various tumors are often predictive of better outcome. These capabilities, once validated, could provide for an important opportunity to individualize therapy thereby minimizing unnecessary systemic toxicity associated with ineffective therapies with the additional advantage of improving overall patient health care and associated costs. In this report, we provide a brief technical overview of DW-MRI acquisition protocols, quantitative image analysis approaches and review studies which have implemented DW-MRI for the purpose of early prediction of cancer treatment response. © 2010 Wiley-Liss, Inc. Source


Low N.,University of Bern
Cochrane database of systematic reviews (Online) | Year: 2012

There are two main strategies for the prevention of post-abortal upper genital tract infection: antibiotics given around the time of surgery for all women; and 'screen-and-treat', in which all women presenting for abortion are screened for genital infections and those with positive results are treated. To determine:1. the effectiveness of antibiotic prophylaxis in preventing post-abortal upper genital tract infection; 2. the most effective antibiotic regimen; 3. the most effective strategy. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, EMBASE, POPLINE and LILACS. The search was last updated in May 2011. Randomised controlled trials (RCTs) in any language including women undergoing induced first trimester surgical or medical abortion, comparing: 1) any antibiotic regimen to placebo, nothing, or another antibiotic; 2) screen-and-treat versus antibiotics. The primary outcome was the proportion of women diagnosed with post-abortal upper genital tract infection. Two reviewers independently selected references and extracted data. We calculated risk ratios (RR) with 95% confidence intervals (CI). We used meta-analysis where appropriate and examined between trial heterogeneity using the I(2) statistic. In the presence of between trial heterogeneity we also estimated the 95% prediction interval (PI). A total of 703 unique items was identified. We included 19 RCTs. There was evidence of small study biases (Egger test, P = 0.002). In 15 placebo-controlled RCTs there was an effect of antibiotic prophylaxis (pooled RR 0.59, 95% CI 0.46 to 0.75, 95% PI 0.30 to 1.14, I(2) = 39%). There were insufficient data (three trials) to determine whether one regimen was superior to another. In one trial, the incidence of post-abortal upper genital tract infection was higher in women allocated to the screen-and-treat strategy (RR 1.53, 95% CI 0.99 to 2.36). Antibiotic prophylaxis at the time of first trimester surgical abortion is effective in preventing post-abortal upper genital tract infection. Evidence of between trial heterogeneity suggests that the effect might not apply to all settings, population groups or interventions.This review did not determine the most effective antibiotic prophylaxis regimen. Antibiotic choice should take into account the local epidemiology of genital tract infections, including sexually transmitted infections.Further RCTs comparing different antibiotics or combinations of antibiotics with each other would be useful. Such trials could be done in low and middle income countries and where the prevalence of genital tract infections in women presenting for abortion is high. Source


Huber A.,University of Bern
Swiss medical weekly | Year: 2014

Computed tomography (CT) is inferior to the fibroscan and laboratory testing in the noninvasive diagnosis of liver fibrosis. On the other hand, CT is a frequently used diagnostic tool in modern medicine. The auxiliary finding of clinically occult liver fibrosis in CT scans could result in an earlier diagnosis. The aim of this study was to analyse quantifiable direct signs of liver remodelling in CT scans to depict liver fibrosis in a precirrhotic stage. Retrospective review of 148 abdominal CT scans (80 liver cirrhosis, 35 precirrhotic fibrosis and 33 control patients). Fibrosis and cirrhosis were histologically proven. The diameters of the three main hepatic veins were measured 1-2 cm before their aperture into the inferior caval vein. The width of the caudate and the right hepatic lobe were divided, and measured horizontally at the level of the first bifurcation of the right portal vein in axial planes (caudate-right-lobe ratio). A combination of both (sum of liver vein diameters divided by the caudate-right lobe ratio) was defined as the ld/crl ratio. These metrics were analysed for the detection of liver fibrosis and cirrhosis. An ld/crl-r <24 showed a sensitivity of 83% and a specificity of 76% for precirrhotic liver fibrosis. Liver cirrhosis could be detected with a sensitivity of 88% and a specificity of 82% if ld/crl-r <20. An ld/crl-r <24 justifies laboratory testing and a fibroscan. This could bring forward the diagnosis and patients would profit from early treatment in a potentially reversible stage of disease. Source


De Marchi S.F.,University of Bern
Current Cardiology Reviews | Year: 2014

The human coronary collateral circulation is prognostically relevant. The understanding of collateral formation and its determinants may guide future therapeutic strategies aiming at promoting collateral growth and functionality, and hence reducing the global burden of coronary artery disease (CAD). © 2014 Bentham Science Publishers. Source


Taborsky M.,University of Bern
Current Biology | Year: 2013

The theory of cooperation predicts that altruism can be established by reciprocity, yet empirical evidence from nature is contentious. Increasingly though, experimental results from social vertebrates challenge the nearly exclusive explanatory power of relatedness for the evolution of cooperation. © 2013 Elsevier Ltd. Source


Skaria A.M.,University of Bern
Dermatology | Year: 2011

Background: Skin cancer of the lip is frequent, and reconstruction after Mohs surgery might be challenging mostly when the postsurgical defect has a size of more than 1 cm 2 and is situated adjacent to the philtrum. Objective: We present a combination of a transposition and advancement flap for the reconstruction of postsurgical defects of the upper lip. Methods: Demonstration of the technique and practical application for this kind of reconstruction. Results: The transposition advancement flap (TAF) presents excellent results for medium defects of the upper lip medially adjacent to the philtrum. Conclusion: The TAF can be used in the reconstruction of the major part of postsurgical lip defects in the medial two fifths of the upper lip without any risk of lip distortion. As this flap is easy to perform, it is an important tool in the armamentarium of the dermatologic surgeon. Copyright © 2011 S. Karger AG, Basel. Source


Sowislo J.F.,University of Basel | Orth U.,University of Bern | Meier L.L.,University of Fribourg
Journal of Abnormal Psychology | Year: 2014

A growing body of longitudinal studies suggests that low self-esteem is a risk factor for depression. However, it is unclear whether other characteristics of self-esteem, besides its level, explain incremental or even greater variance in subsequent depression. We examined the prospective effects of self-esteem level, instability (i.e., the degree of variability in self-esteem across short periods), and contingency (i.e., the degree to which self-esteem fluctuates in response to self-relevant events) on depressive symptoms in 1 overarching model, using data from 2 longitudinal studies. In Study 1, 372 adults were assessed at 2 waves over 6 months, including 40 daily diary assessments at Wave 1. In Study 2, 235 young adults were assessed at 2 waves over 6 weeks, including about 6 daily diary assessments at each wave. Self-esteem contingency was measured by self-report and by a statistical index based on the diary data (capturing event-related fluctuations in self-esteem). In both studies self-esteem level, but not self-esteem contingency, predicted subsequent depressive symptoms. Self-esteem instability predicted subsequent depressive symptoms in Study 2 only, with a smaller effect size than self-esteem level. Also, level, instability, and contingency of self-esteem did not interact in the prediction of depressive symptoms. Moreover, the effect of self-esteem level held when controlling for neuroticism and for all other Big Five personality traits. Thus, the findings provide converging evidence for a vulnerability effect of self-esteem level, tentative evidence for a smaller vulnerability effect of self-esteem instability, and no evidence for a vulnerability effect of self-esteem contingency. © 2014 American Psychological Association. Source


Zheng G.,University of Bern
Computerized Medical Imaging and Graphics | Year: 2010

This paper addresses the problem of estimating the 3D rigid poses of a CT volume of an object from its 2D X-ray projection(s). We use maximization of mutual information, an accurate similarity measure for multi-modal and mono-modal image registration tasks. However, it is known that the standard mutual information measures only take intensity values into account without considering spatial information and their robustness is questionable. In this paper, instead of directly maximizing mutual information, we propose to use a variational approximation derived from the Kullback-Leibler bound. Spatial information is then incorporated into this variational approximation using a Markov random field model. The newly derived similarity measure has a least-squares form and can be effectively minimized by a multi-resolution Levenberg-Marquardt optimizer. Experiments were conducted on datasets from two applications: (a) intra-operative patient pose estimation from a limited number (e.g. 2) of calibrated fluoroscopic images, and (b) post-operative cup orientation estimation from a single standard X-ray radiograph with/without gonadal shielding. The experiment on intra-operative patient pose estimation showed a mean target registration accuracy of 0.8. mm and a capture range of 11.5. mm, while the experiment on estimating the post-operative cup orientation from a single X-ray radiograph showed a mean accuracy below 2° for both anteversion and inclination. More importantly, results from both experiments demonstrated that the newly derived similarity measures were robust to occlusions in the X-ray image(s). © 2010 Elsevier Ltd. Source


Ueda T.,University of Bern
The International journal of oral & maxillofacial implants | Year: 2011

The present study summarizes the long-term clinical observations of edentulous patients treated with mandibular implant-supported overdentures. From 1984 to 1997, edentulous patients were consecutively admitted to treatment with mandibular implant overdentures. The treatment plan was to connect the dentures to only two implants by means of single ball anchors or bars; in patients with special oral conditions, three implants would be placed. Regular maintenance care was provided at least one time per year. The cumulative implant survival rate was calculated. Implant failures were described according to clinical signs at the time of removal and related to the patient's specific history. Crestal bone measurements were performed using computer software. In all, 147 patients with 314 implants were evaluated for 10 to 24 years. Of these, 101 patients were still available; of the 46 patients who were not evaluated, 26 had died or were not ambulatory. Thirteen implants failed during the observation period, resulting in a cumulative survival rate of 85.9% after 24 years. The reasons for removal of implants were peri-implantitis (two implants) and mobility (11 implants). Mean crestal bone loss was 0.54 ± 0.7 mm per implant site after an average observation time of 16.5 ± 3.9 years. The duration of loading had a statistically significant effect on bone loss. The present data exhibit a satisfactory survival rate of implants. An individual analysis of implants with late failures did not reveal a typical failure pattern, but loss of implants without signs of infection was more frequent than loss of implants with signs of peri-implantitis. Source


Finsterer J.,Krankenanstalt Rudolfstiftung | Burgunder J.-M.,University of Bern
European Journal of Medical Genetics | Year: 2014

Background: Genetic background and pathogenesis of motor neuron diseases (MNDs) have been increasingly elucidated over recent years. Aims: To give an overview about publications during the last year concerning the genetic background and phenotypic manifestations of MNDs, such as familial or sporadic amyotrophic lateral sclerosis (fALS, sALS), spinal muscular atrophies (SMA), bulbospinal muscular atrophy (BSMA), and unclassified MNDs. Methods: Pubmed search for literature about ALS, SMA, and BSMA for the period 10/2012 to 9/2013. Results: An increasing number of mutated genes is recognised in fALS but also sALS patients. Genes mutated in sALS include C9orf72, SOD1, TARDBP, FUS, UBQL2, SQSTM1, DCTN1, and UNC13A. Juvenile (onset <20. y) and adult ALS (early onset 20-60. y, late onset >60. y) are differentiated. Juvenile fALS is most frequently caused by mutations in ALS2, SETX, spatacsin, or Sigmar1 and adult fALS by mutations in C9orf72, SOD1, TARDBP, and FUS. Onset, phenotype, progression, and outcome of ALS are variable between different mutations, different genes, and different countries. Differentiation between sALS and fALS cases becomes artificial. Conclusions: Further progress has been made over the last year in the clarification and understanding of the aetiology and pathogenesis of MNDs. However, further effort is needed to answer the many remaining questions. © 2014 Elsevier Masson SAS. Source


Aortic valve replacement using a tissue valve is controversial for patients younger than 60 years old. The long-term survival in this age group, the expected event rates during long-term follow-up, and valve-related complications are not clearly determined. From January 2000 to December 2009, overall survival, valve-related events, and echocardiographic outcomes were analyzed in all patients younger than 60 years of age, who underwent biologic aortic valve replacement. Patients who received a Perimount Carpentier-Edwards pericardial tissue valve (n = 103) were selected and compared with a propensity matched group of 103 patients who received aortic valve replacement using a mechanical bileaflet valve. The mean follow-up was 33 ± 24 months (range, 2-120), and the mean age at implantation was 50.6 ± 8.8 years (bioprosthesis, 55 ± 8.9 years; mechanical valve, 50 ± 8.6 years; P = .03). Survival was significantly reduced in patients after biologic aortic valve replacement (90.3% vs 98%; P = .038). Freedom from all valve-related complications (bioprosthesis, 54.5%; mechanical valve, 51.6%; P = NS) and freedom from reoperation (bioprostheses, 100%; mechanical valve, 98%; P = NS) were comparable in both groups. The average transvalvular mean (11.2 ± 4.2 mm Hg vs 10.5 ± 6.0 mm Hg, P = .05) and peak (19.9 ± 6.7 mm Hg vs 16.7 ± 8.0 mm Hg, P = .03) gradients were greater after biologic aortic valve replacement. Regression of the left ventricular mass index was more pronounced after mechanical valve replacement (118.5 ± 24.9 g/m(2) vs 126.5 ± 38.5 g/m(2); P = NS). The echocardiographic patient-prosthesis mismatch was greater at follow-up after biological aortic valve replacement (0.876 ± 0.2 cm(2)/m(2) vs 1.11 ± 0.4 cm(2)/m(2); P = .01). Oral anticoagulation was a protective factor for survival among the bioprosthetic valve patients (P = .024). In the present limited cohort of patients younger than 60 years old, biologic aortic valve replacement was associated with reduced mid-term survival compared with survival after mechanical aortic valve replacement. Despite similar valve-related event rates in both groups, the better hemodynamic performance of the mechanical valves and/or protective effect of oral anticoagulation seemed to improve the outcome. The transcatheter valve-in-valve intervention as potential treatment of tissue valve degeneration should not be considered the sole bailout strategy for younger patients because no evidence is available that this would improve the outcome. Copyright © 2012 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved. Source


Akinfiev N.N.,RAS Institute of Geology and Mineralogy | Diamond L.W.,University of Bern
Fluid Phase Equilibria | Year: 2010

Experimental measurements of the solubility of CO2 in aqueous NaCl solutions have been assembled from 21 literature studies and tested for consistency using analytical and thermodynamic criteria. Of the 508 data compiled, 170 data (33%) were discarded and 36 were reserved to test the high-pressure dependency of the model. Possible reasons for the observed discrepancies between datasets are discussed. The 302 measurements that satisfy the acceptance criteria have been used to fit Pitzer parameters. These have been incorporated into a semi-empirical, γ-∅ type thermodynamic model that builds upon published equations of state for the unary and binary subsystems. The accepted experimental solubilities are reproduced by the model with a precision of better than 1.6% (one standard deviation) over the entire P-T-x range considered. The new model provides a thermodynamically consistent description of numerous properties of the aqueous liquid in the ternary CO2-H2O-NaCl system, including: the activity coefficients, activities and partial molar volumes of CO2(aq) and Na+Cl-(aq); the activity coefficient and osmotic coefficient of the solvent H2O; the Setchenow coefficient; saturation indices of all four solid phases in the system (CO2-clathrate-hydrate, ice, hydrohalite and halite); and the molar volume, excess molar volume and density of the bulk liquid. These properties can be calculated for any CO2 concentration up to saturation, and for any NaCl concentration (whether stable or metastable). The model is available as a computer code at . © 2010 Elsevier B.V. All rights reserved. Source


Engelhardt B.,University of Bern | Liebner S.,University Hospital Frankfurt
Cell and Tissue Research | Year: 2014

The blood-brain barrier (BBB) is essential for maintaining homeostasis within the central nervous system (CNS) and is a prerequisite for proper neuronal function. The BBB is localized to microvascular endothelial cells that strictly control the passage of metabolites into and out of the CNS. Complex and continuous tight junctions and lack of fenestrae combined with low pinocytotic activity make the BBB endothelium a tight barrier for water soluble moleucles. In combination with its expression of specific enzymes and transport molecules, the BBB endothelium is unique and distinguishable from all other endothelial cells in the body. During embryonic development, the CNS is vascularized by angiogenic sprouting from vascular networks originating outside of the CNS in a precise spatio-temporal manner. The particular barrier characteristics of BBB endothelial cells are induced during CNS angiogenesis by cross-talk with cellular and acellular elements within the developing CNS. In this review, we summarize the currently known cellular and molecular mechanisms mediating brain angiogenesis and introduce more recently discovered CNS-specific pathways (Wnt/β-catenin, Norrin/Frizzled4 and hedgehog) and molecules (GPR124) that are crucial in BBB differentiation and maturation. Finally, based on observations that BBB dysfunction is associated with many human diseases such as multiple sclerosis, stroke and brain tumors, we discuss recent insights into the molecular mechanisms involved in maintaining barrier characteristics in the mature BBB endothelium. © 2014 The Author(s). Source


Allosteric receptor modulation is an attractive concept in drug targeting because it offers important potential advantages over conventional orthosteric agonism or antagonism. Allosteric ligands modulate receptor function by binding to a site distinct from the recognition site for the endogenous agonist. They often have no effect on their own and therefore act only in conjunction with physiological receptor activation. This article reviews the current status of allosteric modulation at family C G-protein coupled receptors in the light of their specific structural features on the one hand and current concepts in receptor theory on the other hand. Family C G-protein-coupled receptors are characterized by a large extracellular domain containing the orthosteric agonist binding site known as the "venus flytrap module" because of its bilobal structure and the dynamics of its activation mechanism. Mutational analysis and chimeric constructs have revealed that allosteric modulators of the calcium-sensing, metabotropic glutamate and GABAB receptors bind to the seven transmembrane domain, through which they modify signal transduction after receptor activation. This is in contrast to taste-enhancing molecules, which bind to different parts of sweet andumamireceptors. The complexity of interactions between orthosteric and allosteric ligands is revealed by a number of adequate biochemical and electrophysiological assay systems. Many allosteric family C GPCR modulators show in vivo efficacy in behavioral models for a variety of clinical indications. The positive allosteric calcium sensing receptor modulator cinacalcet is the first drug of this type to enter the market and therefore provides proof of principle in humans. Copyright © 2011 by The American Society for Pharmacology and Experimental Therapeutics. Source


Gertsch J.,University of Bern | Pertwee R.G.,University of Aberdeen | Di Marzo V.,National Research Council Italy
British Journal of Pharmacology | Year: 2010

It is intriguing that during human cultural evolution man has detected plant natural products that appear to target key protein receptors of important physiological systems rather selectively. Plants containing such secondary metabolites usually belong to unique chemotaxa, induce potent pharmacological effects and have typically been used for recreational and medicinal purposes or as poisons. Cannabis sativa L. has a long history as a medicinal plant and was fundamental in the discovery of the endocannabinoid system. The major psychoactive Cannabis constituent Δ9-tetrahydrocannabinol (Δ9-THC) potently activates the G-protein-coupled cannabinoid receptor CB1 and also modulates the cannabinoid receptor CB 2. In the last few years, several other non-cannabinoid plant constituents have been reported to bind to and functionally interact with CB receptors. Moreover, certain plant natural products, from both Cannabis and other plants, also target other proteins of the endocannabinoid system, such as hydrolytic enzymes that control endocannabinoid levels. In this commentary we summarize and critically discuss recent findings. © 2010 The British Pharmacological Society All rights reserved. Source


Over recent years, it has repeatedly been demonstrated that a longer final fixation (the so-called quiet eye) is beneficial for motor performance. Although this phenomenon has been broadly studied, a satisfying explanation is still lacking. Discussing explanations for the quiet eye benefit, it becomes apparent that contributions from both, cognitive and ecological frameworks, still exhibit conceptual and methodological problems. Therefore, (for a start, for precision tasks) an inhibition mechanism is proposed with the central assumption that the quiet eye shields the processing of performance-relevant cues from interferences. The proposed mechanism proves to be compatible with the current state of research and allows for the deduction of novel predictions. © 2013 Springer-Verlag Berlin Heidelberg. Source


During a mammary immune response, the integrity of the blood-milk barrier is negatively affected and becomes leaky. The aim of the present study was to demonstrate the blood origin, and to investigate changes in the concentration, of various constituents including immunoglobulins in blood and milk during the early phase of lipopolysaccharide (LPS)-induced mastitis. Five lactating dairy cows received continuous β-hydroxybutyrate (BHBA) clamp infusions to maintain elevated BHBA blood concentrations (1.5 to 2.0 mmol/L) from 48 h before and 8h after LPS administration. One udder quarter was infused with 200 μg of Escherichia coli LPS. A second quarter served as control. Milk and blood samples were taken hourly for 8h postchallenge (PC). The somatic cell count in LPS-challenged quarters was increased from 4h PC to the end of the experiment compared with control quarters. In LPS-challenged quarters, l-lactate, BHBA, lactate dehydrogenase (LDH), IgG(1), and IgG(2) were increased at 3h PC and remained elevated until the end of experiment (8h PC) compared with control quarters. In addition, the optical density values in milk in a nonquantitative ELISA for antibodies directed against bluetongue virus (used as a measure of nonspecific antibody transfer; all animals were vaccinated) increased and, thus, indicates an increase in these antibodies in response to LPS treatment. l-Lactate concentration also increased in blood 2h PC and in the milk of control quarters during the experiment from 3h PC. A second experiment was conducted in vitro to investigate a possible contribution from destructed milk cells to l-lactate concentration and activity of LDH in milk. Aliquots of milk samples (n=8) were frozen (-20°C) or disrupted with ultrasound, respectively. Freeze thawing and ultrasound treatment increased LDH in milk samples, but had no effect on l-lactate concentrations. Results suggest that intramammary infusion of LPS induces a systemic response, as evidenced by an elevation of blood l-lactate concentration. The concomitant changes of all investigated components suggest that they were blood derived. However, the increase in blood components in the milk is not necessarily supportive of the mammary immune system, and likely a side effect of reduced blood-milk barrier integrity. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved. Source


Wit J.M.,Leiden University | Kiess W.,University of Leipzig | Mullis P.,University of Bern
Best Practice and Research: Clinical Endocrinology and Metabolism | Year: 2011

After a proper medical history, growth analysis and physical examination of a short child, followed by radiological and laboratory screening, the clinician may decide to perform genetic testing. We propose several clinical algorithms that can be used to establish the diagnosis. GH1 and GHRHR should be tested in children with severe isolated growth hormone deficiency and a positive family history. A multiple pituitary dysfunction can be caused by defects in several genes, of which PROP1 and POU1F1 are most common. GH resistance can be caused by genetic defects in GHR, STAT5B, IGF1, IGFALS, which all have their specific clinical and biochemical characteristics. IGF-I resistance is seen in heterozygous defects of the IGF1R. If besides short stature additional abnormalities are present, these should be matched with known dysmorphic syndromes. If no obvious candidate gene can be determined, a whole genome approach can be taken to check for deletions, duplications and/or uniparental disomies. © 2010 Elsevier Ltd. All rights reserved. Source


Monticelli L.A.,Cornell University | Osborne L.C.,Cornell University | Noti M.,University of Bern | Tran S.V.,Cornell University | And 2 more authors.
Proceedings of the National Academy of Sciences of the United States of America | Year: 2015

The barrier surfaces of the skin, lung, and intestine are constantly exposed to environmental stimuli that can result in inflammation and tissue damage. Interleukin (IL)-33-dependent group 2 innate lymphoid cells (ILC2s) are enriched at barrier surfaces and have been implicated in promoting inflammation; however, the mechanisms underlying the tissue-protective roles of IL-33 or ILC2s at surfaces such as the intestine remain poorly defined. Here we demonstrate that, following activation with IL-33, expression of the growth factor amphiregulin (AREG) is a dominant functional signature of gut-associated ILC2s. In the context of a murine model of intestinal damage and inflammation, the frequency and number of AREG-expressing ILC2s increases following intestinal injury and genetic disruption of the endogenous AREG-epidermal growth factor receptor (EGFR) pathway exacerbated disease. Administration of exogenous AREG limited intestinal inflammation and decreased disease severity in both lymphocyte-sufficient and lymphocyte-deficient mice, revealing a previously unrecognized innate immune mechanism of intestinal tissue protection. Furthermore, treatment with IL-33 or transfer of ILC2s ameliorated intestinal disease severity in an AREG-dependent manner. Collectively, these data reveal a critical feedback loop in which cytokine cues from damaged epithelia activate innate immune cells to express growth factors essential for ILC-dependent restoration of epithelial barrier function and maintenance of tissue homeostasis. Source


Wolf M.,University of Groningen | Wolf M.,Max Planck Institute for Human Development | Van Doorn G.S.,University of Bern | Weissing F.J.,University of Groningen
Proceedings of the Royal Society B: Biological Sciences | Year: 2011

Recent research focuses on animal personalities, that is individual differences in behaviour that are consistent across contexts and over time. From an adaptive perspective, such limited behavioural plasticity is surprising, since a more flexible structure of behaviour should provide a selective advantage. Here, we argue that consistency can be advantageous because it makes individuals predictable. Predictability, however, can only be advantageous if at least some individuals in the population respond to individual differences. Consequently, the evolution of consistency and responsiveness are mutually dependent. We present a general analysis of this coevolutionary feedback for scenarios that can be represented as matrix games with two pure strategies (e.g. hawk-dove game, snowdrift game). We first show that responsive strategies are favoured whenever some individual differences are present in the population (e.g. due to mutation and drift). We then show that the presence of responsive individuals can trigger a coevolutionary process between responsiveness and consistency that gives rise to populations in which responsive individuals coexist with unresponsive individuals who show high levels of adaptive consistency in their behaviour. Next to providing an adaptive explanation for consistency, our results also link two key features associated with personalities, individual differences in responsiveness and behavioural consistency. © 2010 The Royal Society. Source


We present a dimensionless index that quantifies the degree of cloudiness of the atmosphere of a transiting exoplanet. Our cloudiness index is based on measuring the transit radii associated with the line center and wing of the sodium or potassium line. In deriving this index, we revisited the algebraic formulae for inferring the isothermal pressure scale height from transit measurements. We demonstrate that the formulae of Lecavelier et al. and Benneke & Seager are identical: the former is inferring the temperature while assuming a value for the mean molecular mass and the latter is inferring the mean molecular mass while assuming a value for the temperature. More importantly, these formulae cannot be used to distinguish between cloudy and cloud-free atmospheres. We derive values of our cloudiness index for a small sample of seven hot Saturns/Jupiters taken from Sing et al. We show that WASP-17b, WASP-31b, and HAT-P-1b are nearly cloud-free at visible wavelengths. We find the tentative trend that more irradiated atmospheres tend to have fewer clouds consisting of sub-micron-sized particles. We also derive absolute sodium and/or potassium abundances ∼102 cm-3 for WASP-17b, WASP-31b, and HAT-P-1b (and upper limits for the other objects). Higher-resolution measurements of both the sodium and potassium lines, for a larger sample of exoplanetary atmospheres, are needed to confirm or refute this trend. © 2016. The American Astronomical Society. All rights reserved. Source


Gallati S.,University of Bern
Application of Clinical Genetics | Year: 2014

The mechanisms responsible for the determination of phenotypes are still not well understood; however, it has become apparent that modifier genes must play a considerable role in the phenotypic heterogeneity of Mendelian disorders. Significant advances in genetic technologies and molecular medicine allow huge amounts of information to be generated from individual samples within a reasonable time frame. This review focuses on the role of modifier genes using the example of cystic fibrosis, the most common lethal autosomal recessive disorder in the white population, and discusses the advantages and limitations of candidate gene approaches versus genome-wide association studies. Moreover, the implications of modifier gene research for other monogenic disorders, as well as its significance for diagnostic, prognostic, and therapeutic approaches are summarized. Increasing insight into modifying mechanisms opens up new perspectives, dispelling the idea of genetic disorders being caused by one single gene. © 2014 Gallati. This work is published by Dove Medical Press Limited. Source


Windecker S.,University of Bern | Bax J.J.,Leiden University | Myat A.,Kings College London | Stone G.W.,Columbia University Medical Center | Marber M.S.,Kings College London
The Lancet | Year: 2013

Over the past five decades, management of acute ST-segment elevation myocardial infarction (STEMI) has evolved substantially. Current treatment encompasses a systematic chain of network activation, antithrombotic drugs, and rapid instigation of mechanical reperfusion, although pharmacoinvasive strategies remain relevant. Secondary prevention with drugs and lifestyle modifications completes the contemporary management package. Despite a tangible improvement in outcomes, STEMI remains a frequent cause of morbidity and mortality, justifying the quest to find new therapeutic avenues. Ways to reduce delays in doing coronary angioplasty after STEMI onset include early recognition of symptoms by patients and prehospital diagnosis by paramedics so that the emergency room can be bypassed in favour of direct admission to the catheterisation laboratory. Mechanical reperfusion can be optimised by improvements to stent design, whereas visualisation of infarct size has been improved by developments in cardiac MRI. Novel treatments to modulate the inflammatory component of atherosclerosis and the vulnerable plaque include use of bioresorbable vascular scaffolds and anti-proliferative drugs. Translational efforts to improve patients' outcomes after STEMI in relation to cardioprotection, cardiac remodelling, and regeneration are also being realised. Source


Alvarez-Garcia G.,Complutense University of Madrid | Frey C.F.,Complutense University of Madrid | Frey C.F.,University of Bern | Mora L.M.O.,Complutense University of Madrid | Schares G.,Friedrich Loeffler Institute
Trends in Parasitology | Year: 2013

Bovine besnoitiosis, which is caused by the cyst-forming apicomplexan parasite Besnoitia besnoiti, is a chronic and debilitating vector-borne disease characterized by both cutaneous and systemic manifestations. In Europe, this parasitic disease appeared in a few restricted areas in France and Portugal since the first recorded cases in the beginning of the 20th century. However, at present, the disease is considered to be re-emerging by the European Food Safety Authority due to an increased number of cases and the geographic expansion of besnoitiosis into cattle herds in several European countries. In this review, we will provide an update of the epidemiology and impact of B. besnoiti infection. Strategies to control this parasitic disease will also be discussed. © 2013 Elsevier Ltd. Source