The National and Kapodistrian University of Athens , usually referred to simply as the University of Athens, has been in continuous operation since its establishment in 1837. It is the oldest higher education institution in the modern Greek state. Wikipedia.
Vlachantoni I.T.,National and Kapodistrian University of Athens
Sleep medicine reviews | Year: 2013
Obstructive sleep apnea (OSA) is associated with increased arterial stiffness, a cumulative indicator of arterial health. Continuous positive airway pressure (CPAP) is the gold standard treatment for OSA. We conducted a meta-analysis of the available literature investigating the effect of CPAP on arterial stiffness in patients with OSA. Fifteen articles (n = 615 patients) assessing indices of arterial stiffness were identified. Five different meta-analyses were performed assessing: a) all indices of arterial stiffness, b) augmentation index (AIx), c) all pulse wave velocities (PWV), d) brachial-ankle PWV and e) carotid-femoral PWV. Pooled standardized mean differences (SMDs) and weighted mean differences (WMDs) were appropriately calculated through fixed or random effects models after assessing between-study heterogeneity. A significant improvement of all indices of arterial stiffness was observed after CPAP treatment (SMD = -0.74; 95%CI: -1.08 to -0.41). AIx and PWVs were also significantly improved (WMD = -4.86; 95%CI: -7.31 to -2.41 and WMD = -0.87; 95%CI: -0.98 to -0.77, respectively), as well as brachial-ankle PWV and carotid-femoral PWV (WMD = -0.86; 95%CI: -0.97 to -0.75 and WMD = -1.21; 95%CI:-1.92 to -0.50, respectively). Neither the proportion of compliant patients nor the duration of CPAP use altered the effect of arterial stiffness reduction after CPAP treatment. In conclusion, our meta-analyses showed significant improvements in all indices of arterial stiffness after CPAP treatment in patients with OSA. As clinical use of arterial stiffness is growing in popularity, the efficacy of this useful tool in assessing cardiovascular risk reduction among patients with OSA treated with CPAP needs to be further explored. Copyright © 2012 Elsevier Ltd. All rights reserved.
Santamouris M.,National and Kapodistrian University of Athens
Solar Energy | Year: 2014
The temperature of cities continues to increase because of the heat island phenomenon and the undeniable climatic change. The observed high ambient temperatures intensify the energy problem of cities, deteriorates comfort conditions, put in danger the vulnerable population and amplify the pollution problems. To counterbalance the phenomenon, important mitigation technologies have been developed and proposed. Among them, technologies aiming to increase the albedo of cities and the use of vegetative - green roofs appear to be very promising, presenting a relatively high heat island mitigation potential. This paper aims to present the state of the art on both the above technologies, when applied in the city scale. Tenths of published studies have been analysed. Most of the available data are based on simulation studies using mesoscale modeling techniques while important data are available from the existing experimental studies. When a global increase of the city's albedo is considered, the expected mean decrease of the average ambient temperature is close to 0.3. K per 0.1 rise of the albedo, while the corresponding average decrease of the peak ambient temperature is close to 0.9. K. When only cool roofs are considered, the analysis of the existing data shows that the expected depression rate of the average urban ambient temperature varies between 0.1 and 0.33. K per 0.1 increase of the roofs albedo with a mean value close to 0.2. K. As it concerns green roofs, existing simulation studies show that when applied on a city scale, they may reduce the average ambient temperature between 0.3 and 3. K. Detailed analysis of many studies reporting a comparison of the mitigation potential of both technologies has permitted the definition of the limits, the boundaries and the conditions under which the considered technologies reach their better performance, in a synthetic way. © 2012 Elsevier Ltd.
Stefanis L.,National and Kapodistrian University of Athens
Cold Spring Harbor Perspectives in Medicine | Year: 2012
α-Synuclein is a presynaptic neuronal protein that is linked genetically and neuropathologically to Parkinson's disease (PD). α-Synuclein may contribute to PD pathogenesis in a number of ways, but it is generally thought that its aberrant soluble oligomeric conformations, termed protofibrils, are the toxic species that mediate disruption of cellular homeostasis and neuronal death, through effects on various intracellular targets, including synaptic function. Furthermore, secreted α-synuclein may exert deleterious effects on neighboring cells, including seeding of aggregation, thus possibly contributing to disease propagation. Although the extent to which α-synuclein is involved in all cases of PD is not clear, targeting the toxic functions conferred by this protein when it is dysregulated may lead to novel therapeutic strategies not only in PD, but also in other neurodegenerative conditions, termed synucleinopathies. © 2012 Cold Spring Harbor Laboratory Press, all rights reserved.
Kokotos C.G.,National and Kapodistrian University of Athens
Organic Letters | Year: 2013
A cheap and fast construction of both enantiomers of substituted succinimides is reported. α- or β-amino acids, such as β-phenylalanine and α-tert-butyl aspartate, were found to be efficient organocatalysts for the reaction between α,α-disubstituted aldehydes and maleimides. Products containing contiguous quaternary-tertiary stereogenic centers are obtained in high to quantitative yields and excellent selectivities utilizing low catalyst loadings (0.5-3.5%). Finally, a one-pot efficient asymmetric synthesis of lactones is described. © 2013 American Chemical Society.
Santamouris M.,National and Kapodistrian University of Athens
Renewable and Sustainable Energy Reviews | Year: 2013
Heat island phenomenon rises the temperature of cities, increases the energy demand for cooling and deteriorates comfort conditions in the urban environment. To counterbalance the impact of the phenomenon, important mitigation techniques have been proposed and developed. Pavements present a very high fraction of the urban areas and contribute highly to the development of heat island in cities. The use of cool pavements presenting substantially lower surface temperature and reduced sensible heat flux to the atmosphere, appears to be one of the most important proposed mitigation solutions. The present paper investigates and describes the actual state of the art on the field of cool pavements. The main thermal and optical parameters defining the thermal performance of pavements are analyzed. Almost all of the developed technologies, where data and results are available, are considered while emphasis is given on the presentation of reflective and permeable/water retentive pavements. The main technological achievements on both fields are reviewed while existing applications are described and performance data are given when available. The existing results clearly show that the mitigation and cooling potential of cool pavements is very significant and can highly contribute to decrease temperature on the urban environment. © 2013 Elsevier Ltd. All rights reserved.
Dafni U.,National and Kapodistrian University of Athens
Circulation: Cardiovascular Quality and Outcomes | Year: 2011
This statistical primer presents the landmark analysis method, exploring its appropriate use and interpretation while recognizing its limitationsThis observational method is used for comparing time-to-event outcome between groups determined during study follow-upThe goal of the landmark method is to estimate in an unbiased way the time-to-event probabilities in each group conditional on the group membership of patients at a specific time point, the landmark timeThe need that led to its development, the impact of the method, and its pros and cons, along with available alternative approaches, are presentedSimulations explore its performance, using realistic parameters from arecent cardiovascular studyAs long as the limitations of the method are recognized and the interpretation of its results clearly reflect their "conditional" nature, landmark analysis, 25 years from its introduction, can still be of value. © 2011 American Heart Association, Inc.
Kassi E.,National and Kapodistrian University of Athens
BMC medicine | Year: 2011
Metabolic syndrome (MetS) is a complex disorder defined by a cluster of interconnected factors that increase the risk of cardiovascular atherosclerotic diseases and diabetes mellitus type 2. Currently, several different definitions of MetS exist, causing substantial confusion as to whether they identify the same individuals or represent a surrogate of risk factors. Recently, a number of other factors besides those traditionally used to define MetS that are also linked to the syndrome have been identified. In this review, we critically consider existing definitions and evolving information, and conclude that there is still a need to develop uniform criteria to define MetS, so as to enable comparisons between different studies and to better identify patients at risk. As the application of the MetS model has not been fully validated in children and adolescents as yet, and because of its alarmingly increasing prevalence in this population, we suggest that diagnosis, prevention and treatment in this age group should better focus on established risk factors rather than the diagnosis of MetS.
Terpos E.,National and Kapodistrian University of Athens
Journal of clinical oncology : official journal of the American Society of Clinical Oncology | Year: 2013
The aim of the International Myeloma Working Group was to develop practice recommendations for the management of multiple myeloma (MM) -related bone disease. An interdisciplinary panel of clinical experts on MM and myeloma bone disease developed recommendations based on published data through August 2012. Expert consensus was used to propose additional recommendations in situations where there were insufficient published data. Levels of evidence and grades of recommendations were assigned and approved by panel members. Bisphosphonates (BPs) should be considered in all patients with MM receiving first-line antimyeloma therapy, regardless of presence of osteolytic bone lesions on conventional radiography. However, it is unknown if BPs offer any advantage in patients with no bone disease assessed by magnetic resonance imaging or positron emission tomography/computed tomography. Intravenous (IV) zoledronic acid (ZOL) or pamidronate (PAM) is recommended for preventing skeletal-related events in patients with MM. ZOL is preferred over oral clodronate in newly diagnosed patients with MM because of its potential antimyeloma effects and survival benefits. BPs should be administered every 3 to 4 weeks IV during initial therapy. ZOL or PAM should be continued in patients with active disease and should be resumed after disease relapse, if discontinued in patients achieving complete or very good partial response. BPs are well tolerated, but preventive strategies must be instituted to avoid renal toxicity or osteonecrosis of the jaw. Kyphoplasty should be considered for symptomatic vertebral compression fractures. Low-dose radiation therapy can be used for palliation of uncontrolled pain, impending pathologic fracture, or spinal cord compression. Orthopedic consultation should be sought for long-bone fractures, spinal cord compression, and vertebral column instability.
Protopapas A.,National and Kapodistrian University of Athens
Philosophical Transactions of the Royal Society B: Biological Sciences | Year: 2014
The 'rapid temporal processing' and the 'temporal sampling framework' hypotheses have been proposed to account for the deficits in language and literacy development seen in specific language impairment and dyslexia. This paper reviews these hypotheses and concludes that the proposed causal chains between the presumed auditory processing deficits and the observed behavioural manifestation of the disorders are vague and not well established empirically. Several problems and limitations are identified. Most data concern correlations between distantly related tasks, and there is considerable heterogeneity and variability in performance as well as concerns about reliability and validity. Little attention is paid to the distinction between ostensibly perceptual and metalinguistic tasks or between implicit and explicit modes of performance, yet measures are assumed to be pure indicators of underlying processes or representations. The possibility that diagnostic categories do not refer to causally and behaviourally homogeneous groups needs to be taken seriously, taking into account genetic and neurodevelopmental studies to construct multiple-risk models. To make progress in the field, cognitive models of each task must be specified, including performance domains that are predicted to be deficient versus intact, testing multiple indicators of latent constructs and demonstrating construct reliability and validity. © 2013 The Author(s) Published by the Royal Society. All rights reserved.
Mavragani C.P.,National and Kapodistrian University of Athens |
Moutsopoulos H.M.,National and Kapodistrian University of Athens
Annual Review of Pathology: Mechanisms of Disease | Year: 2014
Sjögren's syndrome (SS) is a chronic autoimmune disorder that typically affects exocrine glands-mainly labial and lacrimal-leading to complaints of dry mouth and eyes. Given that periepithelial mononuclear cell infiltrates, both in exocrine glands and in other parenchymal organs (kidney, lung, and liver), are the histopathological disease hallmark, the term autoimmune epithelitis has been proposed. B cell hyperactivity is another cardinal SS feature manifested by the presence of autoantibodies and hypergammaglobulinemia, as well as clinical/serological phenotypes mediated by immune complexes, such as peripheral neuropathy, vasculitic lesions, and hypocomplementemia. These have been designated adverse predictors for lymphoma development in approximately 5% to 10% of patients. Activation of the type I interferon/B cell-Activating factor axis in SS has recently attracted particular attention. Inappropriate overexpression of endogenous nucleic acids in a genetically susceptible individual might provide a plausible scenario for the immune activation observed in SS. © 2014 by Annual Reviews. All rights reserved.