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News Article | November 30, 2016
Site: phys.org

Przewalski's horse, a species of wild horse that has been successfully reintroduced to the Gobi Desert, shares its pasture grounds with wild asses and free-roaming domestic horses. A scarce supply of food could lead to food competition among the different species, especially if they make the same dietary choices. A team led by researchers from Vetmeduni Vienna therefore chemically analysed the tail hairs of the animals to determine the seasonal dietary habits of the three species. While the wild ass switches from being a grazer in the summer to also browse in the winter, the wild and domestic horses eat exclusively grass all year round. In the lean winter months, this leads to increased food competition between wild and domestic horses. This realisation could help improve wildlife management measures for the Przewalski's horse in the future. The study was published in the Journal of Applied Ecology. Przewalski's horses went extinct in the wild in 1968. Successful breeding programmes at zoos around the world helped to reintroduce the animals in the Great Gobi B protected area in southwestern Mongolia since 1992. The wild horses share the extreme habitat of the Gobi Desert with two other equid species: the Asiatic wild ass, also called khulan, and the free-ranging domestic horses of local nomads. For the preservation of the wild Przewalski's horse, it is important to understand if and how the three related species compete for food in the protected area. Competition between Przewalski's horses and domestic horses in the winter Martina Burnik Šturm and Petra Kaczensky from the Research Institute of Wildlife Ecology at Vetmeduni Vienna, in cooperation with the Leibnitz Institute for Zoo and Wildlife Research in Berlin, used a special method based on the chemical analysis of tail hairs to investigate the dietary habits of the animals. The analysis allowed them to determine the composition of the diet of each of the three species, which led to the discovery of increased dietary competition in the winter months. The chemical analysis of the tail hairs revealed that Przewalski's horses and domestic horses are year-round grazers. Khulan, on the other hand, switch from grazing in the summer to a high proportion of foliage in the winter. "When food becomes scarce in the long winter months, competition can be expected especially between the two species of horse," explains Martina Burnik Šturm. Competition considerably less in the summer In the summer, the food supply is relatively high. At the same time, the local nomads leave the Gobi and take their horses to the high pastures of the surrounding mountains. "In the hot season, Przewalski's horses mainly graze near sources of water. Khulan, on the other hand, also graze on pastures far from water sources as they are better able to conserve water. The potential for pasture competition in the summer is therefore relatively low among the three species in the Great Gobi B protected area," adds Petra Kaczensky. Chemical composition of the hairs holds information about dietary choices The chemical analysis used by Burnik Šturm and Kaczensky measures so-called stable isotopes in the tail hairs. "Stable isotopes are atoms of of the same chemical element with the same number of protons but different number of neutrons and thus with different masses. The isotope values in the body tissue of living organisms are the result of the isotope values in the environment and of the animal's metabolism," explains Burnik Šturm. Grasses and shrubs in the Gobi Desert exhibit different values of carbon isotopes, which make it possible to differentiate between grazers and browsers. Because the tail hairs of horses grow at a regular rate, they act as an archive storing the isotope values at each growth stage. The longer the hair, the farther back into the past the researchers can look. "If you know how fast the hairs grow, you can date specific hair segments and clearly assign them to a certain season. Consecutive hair segments therefore provide valuable information about the diet and water balance of an individual animal," explains Burnik Šturm. Protected area in the Gobi Desert to secure the survival of Przewalski's horse International research teams, under the direction of Vetmeduni Vienna and in close cooperation with the Great Gobi B protected area, have for years been committed to the reintroduction programme in the Gobi Desert. The long-term goal is to establish a self-sustaining and viable population of Przewalski's horses, but also to protect other key species such as the khulan. An exact understanding of the dietary behaviour of the Przewalski's horse and the khulan are important for improving the conditions in the protected area. The high potential for pasture competition between domestic and wild horses highlights the need for stricter regulation and a restriction on the grazing of domestic horses. The establishment of artificial water sources should be well considered to avoid infringing on the khulan's areas of retreat. Explore further: Tail hair as an indicator of behaviour and ecology in horses More information: Martina Burnik Šturm et al. Sequential stable isotope analysis reveals differences in dietary history of three sympatric equid species in the Mongolian Gobi, Journal of Applied Ecology (2016). DOI: 10.1111/1365-2664.12825

Schettler G.,Helmholtz Center Potsdam | Oberhansli H.,Helmholtz Center Potsdam | Oberhansli H.,Leibnitz Institute | Stulina G.,Scientific Information Center Interstate Coordination Water Commission | Djumanov J.H.,REPUBLIC RESOURCES
Journal of Hydrology | Year: 2013

We studied 40 artesian wells (AWs) in the Amu Darya Delta. These wells include high-salinity (~52g/l) and saline (5-24g/l) waters but are mostly low-salinity waters (1.3-2.9g/l). The low-salinity AWs cluster into three types, reflecting the variable mixing of different end member solutes: (residual) brines and solutes deriving from silicate alteration, dissolution of limestone and dissolution of gypsum. The solutes are all undersaturated in calcite and gypsum, contain a substantial cation excess against dissolved inorganic carbon and are characterised by low Ca/SO4 ratios. On the basis of the hydrochemical mass budgets of model cases, we demonstrate that Na-rich Cl-brines (45-48%) and a Na2SO4-brine (30-47%) are the dominant solute components. The solutes derived from aluminium silicate alteration are minor components (7.3-19.4%). Even less important are solutes from limestone or gypsum dissolution (0.05-3.7%). These waters are unlikely to have originated from sediments hosting gypsum. The low-salinity AWs must have acquired their dominant hydrochemical signatures under non-equilibrium conditions between their remote (unknown) seepage areas and their discharge locations. This acquisition may have begun during the early hydrochemical groundwater evolution when meteoric or surface water passed the critical zone under an arid climate regime. Warmer saline AWs (~40°C) hosted in deeper Cretaceous formations contain a high portion of NaCl-rich brine (85%) and some are saturated in gypsum. These waters were derived from fluids rising along faults from pre-Cretaceous strata. The high-salinity and relatively cold AWs discharge close to the retreating Aral Sea south of its western basin. These AWs are suboxic, and Si concentrations are very low. The AW hydrochemical signatures reflect the dissolution of halite and gypsum. We observed positive correlations between temperature, Br, B and Si. The temperature correlation with bromide likely documents the transformation of organically bound Br. The silica concentrations in low-salinity AWs southeast of the Aral Sea (eastern basin) are close to quartz saturation and define a chemical Si-geothermometer. © 2013 Elsevier B.V.

Schettler G.,Helmholtz Center Potsdam | Oberhansli H.,Helmholtz Center Potsdam | Oberhansli H.,Leibnitz Institute | Stulina G.,Scientific Information Center Interstate Coordination Water Commission | And 2 more authors.
Journal of Hydrology | Year: 2013

The Aral Sea, which has been affected by lake level lowering of approximately 25m and a salinity increase from 10 to >100g/l since 1963, represents, along with the Amu Dary Delta a dynamic hydrological system under an arid climate regime. The system receives river water inflow at high seasonal and inter-annual variability from remote alpine source areas. In the Amu Darya Delta, there is a distinct salinity contrast between the low-salinity river water (~1g/l) and the salinity of the unconfined GW (GWunconf: 10-95g/l). The GWunconf levels are predominantly controlled by the seepage of the river water inflow and GW discharge into the shrinking Aral Sea.In June 2009 and August 2009, we sampled water from various sources including surface waters, GWunconf, lake water and soil leachates for chemical analyses. Evaporative enrichment, precipitation/dissolution of gypsum and precipitation of calcite drive the GWunconf to an NaCl(SO4) water type presenting a positive correlation between Na and SO4.We model the hydrochemical evolution of the GWunconf in a box model which considers the capillary rise of near-surface GW, the precipitation of minerals in the unsaturated horizon and the seasonal re-flushing of adhesive residual brines and soluble salts. The model documents a rapid increase in salinity over a few annual cycles. Furthermore, the model simulations demonstrate the importance of the aeolian redistribution of soluble salts on the hydrochemical GW evolution. In a lab experiment, halite, hexahydrite and starkeyite are precipitated during the late stages of evaporative enrichment from a representative local brine.Processes specific to different water compartments plausibly explain the variations of selected element ratios. For example, the precipitation of low-Sr calcite in irrigation canals and natural river branches of the delta lowers Ca/Sr. The dissolution of gypsum in soils (Ca/Sr mole ratio~150) and the possible precipitation of SrSO4 associated with Sr-depletion in adhesive residual brines increases Ca/Sr in seepage and re-increases Ca/Sr in the unconfined GW. Aral Sea water, which receives high-Ca/Sr surface and groundwater inflow, developed due to continued precipitation of high-Ca/Sr calcite the almost lowest Ca/Sr ratio (~25) over time. We observed spatial variations in the GWunconf composition: (i) ammonium levels increase strongly due to interaction with lake sediments rich in organic matter and (ii) distinct increases in levels of nitrate, U, Mo and Se locally reflect oxygenation when GW levels decrease. The Amu Darya Delta acts as a sink for boron (uptake via terrestrial vegetation) and a source for bromide (release by degradation of organically-bound Br). Our results concerning the hydrochemical evolution of the GWunconf and additional data from the Aral Sea constrain the parameter 'GW discharge' in water budget models of the lake and improve the basis for palaeoclimatic interpretations of sediment records from the Aral Sea. © 2013 Elsevier B.V.

Minden K.,Leibnitz Institute | Minden K.,Charité - Medical University of Berlin | Niewerth M.,Leibnitz Institute | Zink A.,Leibnitz Institute | And 5 more authors.
Rheumatology (United Kingdom) | Year: 2012

Objective. To assess the outcome of adult patients with JIA who received etanercept (ETA) during childhood.Methods. JuMBO (Juvenile arthritis MTX/Biologics long-term Observation) is an ongoing prospective cohort study. It follows adult JIA patients who were formerly included in the national JIA biologic register. In JuMBO, clinical status, therapy and the occurrence of adverse events are documented every 6 months by physicians; additionally, patient-derived data are included [e.g. functional capacity and health-related quality of life (HRQoL)]. Here, data from the last available visit of patients were analysed.Results. Until December 2010, 346 patients with a median age of 21 years were included in JuMBO. The majority of them had polyarthritis. Seventy-eight per cent of them were still on DMARDs, 45% on ETA. The disease was inactive in about one in five patients. A restricted functional capacity was reported by 51% of participants and fatigue by 76%. The patients judged their HRQoL to be lower than a reference group from the general population, but only with regard to physical health. HRQoL correlated with the patient's perceived fatigue. Most frequently observed comorbidities in the young adults with JIA were disease related and included uveitis, IBDs and psoriasis. During the observation period, 2.1 severe infections and 1.5 new-onset autoimmune events per 100 patient-years were reported in patients on ETA, respectively.Conclusion. The first data from the JuMBO register indicate an improved long-term outcome of patients with severe JIA treated in the biologic era and an acceptable safety profile of ETA. © The Author 2012. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved.

Gloster A.T.,TU Dresden | Gloster A.T.,University of Basel | Klotsche J.,Leibnitz Institute | Gerlach A.L.,University of Cologne | And 7 more authors.
Journal of Consulting and Clinical Psychology | Year: 2014

Objective: The mechanisms of action underlying treatment are inadequately understood. This study examined 5 variables implicated in the treatment of panic disorder with agoraphobia (PD/AG): catastrophic agoraphobic cognitions, anxiety about bodily sensations, agoraphobic avoidance, anxiety sensitivity, and psychological flexibility. The relative importance of these process variables was examined across treatment phases: (a) psychoeducation/interoceptive exposure, (b) in situ exposure, and (c) generalization/follow-up. Method: Data came from a randomized controlled trial of cognitive behavioral therapy for PD/AG (n = 301). Outcomes were the Panic and Agoraphobia Scale (Bandelow, 1995) and functioning as measured in the Clinical Global Impression scale (Guy, 1976). The effect of process variables on subsequent change in outcome variables was calculated using bivariate latent difference score modeling. Results: Change in panic symptomatology was preceded by catastrophic appraisal and agoraphobic avoidance across all phases of treatment, by anxiety sensitivity during generalization/follow-up, and by psychological flexibility during exposure in situ. Change in functioning was preceded by agoraphobic avoidance and psychological flexibility across all phases of treatment, by fear of bodily symptoms during generalization/follow-up, and by anxiety sensitivity during exposure. Conclusions: The effects of process variables on outcomes differ across treatment phases and outcomes (i.e., symptomatology vs. functioning). Agoraphobic avoidance and psychological flexibility should be investigated and therapeutically targeted in addition to cognitive variables. (PsycINFO Database Record (c) 2014 APA, all rights reserved). © 2013 American Psychological Association.

PubMed | Charité - Medical University of Berlin, University of Bern, Leibnitz Institute and University of Duisburg - Essen
Type: Journal Article | Journal: Clinical and experimental rheumatology | Year: 2015

To analyse the nationwide prevalence of uveitis in JIA and its complications over a whole decade.We conducted a prospective, observational and cross-sectional study including all JIA patients from a National Paediatric Rheumatological Database (NPRD) with a uveitis add-on module in Germany (2002-2013). Temporal changes in uveitis prevalence, related secondary complications and anti-inflammatory medication were evaluated.A total of 60 centres including 18,555 JIA patients (mean 3,863 patients/year, SD=837) were documented in the NPRD between 2002 and 2013. The mean age of the patients was 11.4 4.6 years, their mean disease duration 4.4 3.7 years. Among them, 66.9% were female and 51.7% ANA positive. Patients mean age at arthritis onset was 6.9 4.5 years. Treatment rates with synthetic and biological DMARDs increased during the observation period (sDMARD: 39.8% to 47.2%, bDMARD: 3.3% to 21.8%). Uveitis prevalence decreased significantly from 2002 to 2013 (13.0% to 11.6%, OR = 0.98, p=0.015). The prevalence of secondary uveitis complications also decreased significantly between 2002 and 2013 (33.6% to 23.9%, OR=0.94, p<0.001). Among the complications, the most common ones were posterior synechiae, cataract and band keratopathy. A significant increase in achieving uveitis inactivity was observed at 30.6% in 2002 and 65.3% in 2013 (OR=1.15, p<0.001).Uveitis prevalence and complications significantly decreased between 2002 and 2013. This may be associated with a more frequent use of DMARDs.

Enghard P.,Charité - Medical University of Berlin | Rieder C.,Charité - Medical University of Berlin | Kopetschke K.,Charité - Medical University of Berlin | Klocke J.R.,Charité - Medical University of Berlin | And 13 more authors.
Annals of the Rheumatic Diseases | Year: 2014

Objectives Proliferative lupus nephritis (LN) is one of the major concerns in the treatment of systemic lupus erythematosus (SLE). Here we evaluate urinary CD4 T cells as a biomarker of active LN and indicator of treatment response. Methods Urinary CD3CD4 T cells were quantified using flow cytometry in 186 urine samples from 147 patients with SLE. Fourteen patients were monitored as follow-up. Thirty-one patients with other nephropathies and 20 healthy volunteers were included as controls. Results In SLE, urinary CD4 T cell counts ≥800/100 ml were observed exclusively in patients with active LN. Receiver operator characteristic analysis documented clear separation of SLE patients with active and non-active LN (area under the curve 0.9969). All patients with up-todate kidney biopsy results showing proliferative LN had high urinary CD4 T cell numbers. In patients monitored under therapy, normalisation of urinary CD4 T cell counts indicated lower disease activity and better renal function. In contrast, patients with persistence of, or increase in, urinary T cells displayed worse outcomes. Conclusions Urinary CD4 T cells are a highly sensitive and specific marker for detecting proliferative LN in patients with SLE. Furthermore, monitoring urinary CD4 T cells may help to identify treatment responders and treatment failure and enable patient-tailored therapy in the future.

Assmus B.,Goethe University Frankfurt | Walter D.H.,Goethe University Frankfurt | Seeger F.H.,Goethe University Frankfurt | Leistner D.M.,Goethe University Frankfurt | And 9 more authors.
JAMA - Journal of the American Medical Association | Year: 2013

Importance: The modest effects of clinical studies using intracoronary administration of autologous bone marrow-derived mononuclear cells (BMCs) in patients with chronic postinfarction heart failure may be attributed to impaired homing of BMCs to the target area. Extracorporeal shock wave treatment has been experimentally shown to increase homing factors in the target tissue, resulting in enhanced retention of applied BMCs. Objective: To test the hypothesis that targeted cardiac shock wave pretreatment with subsequent application of BMCs improves recovery of left ventricular ejection fraction (LVEF) in patients with chronic heart failure. Design, Setting, and Participants: The CELLWAVE double-blind, randomized, placebo-controlled trial conducted among patients with chronic heart failure treated at Goethe University Frankfurt, Germany, between 2006 and 2011. Interventions: Single-blind low-dose (n=42), high-dose (n=40), or placebo (n=21) shock wave pretreatment targeted to the left ventricular anterior wall. Twenty-four hours later, patients receiving shock wave pretreatment were randomized to receive double-blind intracoronary infusion of BMCs or placebo, and patients receiving placebo shock wave received intracoronary infusion of BMCs. Main Outcomes and Measures: Primary end point was change in LVEF from baseline to 4 months in the pooled groups shock wave + placebo infusion vs shock wave + BMCs; secondary end points included regional left ventricular function assessed by magnetic resonance imaging and clinical events. Results: The primary end point was significantly improved in the shock wave + BMCs group (absolute change in LVEF, 3.2% [95% CI, 2.0% to 4.4%]), compared with the shock wave + placebo infusion group (1.0% [95% CI, -0.3% to 2.2%]) (P =.02). Regional wall thickening improved significantly in the shock wave + BMCs group (3.6% [95% CI, 2.0% to 5.2%]) but not in the shock wave + placebo infusion group (0.5% [95% CI, -1.2% to 2.1%]) (P =.01). Overall occurrence of major adverse cardiac events was significantly less frequent in the shock wave + BMCs group (n=32 events) compared with the placebo shock wave + BMCs (n=18) and shock wave + placebo infusion (n=61) groups (hazard ratio, 0.58 [95% CI, 0.40-0.85]; P =.02). Conclusions and Relevance: Among patients with postinfarction chronic heart failure, shock wave-facilitated intracoronary administration of BMCs vs shock wave treatment alone resulted in a significant, albeit modest, improvement in LVEF at 4 months. Determining whether the increase in contractile function will translate into improved clinical outcomes requires confirmation in larger clinical end point trials. Trial Registration: clinicaltrials.gov Identifier: NCT00326989 ©2013 American Medical Association. All rights reserved.

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