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Showing papers by "University of Marburg published in 2004"


Journal ArticleDOI
TL;DR: In this paper, a distinction is made between the learning processes taking place among actors embedded in a community by just being there dubbed buzz and the knowledge attained by investing in building channels of communication called pipelines to selected providers located outside the local milieu.
Abstract: The paper is concerned with spatial clustering of economic activity and its relation to the spatiality of knowledge creation in interactive learning processes. It questions the view that tacit knowledge transfer is confined to local milieus whereas codified knowledge may roam the globe almost frictionlessly. The paper highlights the conditions under which both tacit and codified knowledge can be exchanged locally and globally. A distinction is made between, on the one hand, the learning processes taking place among actors embedded in a community by just being there dubbed buzz and, on the other, the knowledge attained by investing in building channels of communication called pipelines to selected providers located outside the local milieu. It is argued that the co-existence of high levels of buzz and many pipelines may provide firms located in outward-looking and lively clusters with a string of particular advantages not available to outsiders. Finally, some policy implications, stemming from this argumen...

3,942 citations


Journal ArticleDOI
TL;DR: It is therefore of great importance that guidelines and recommendations are presented in formats that are easily interpreted and their implementation programmes must also be well conducted.
Abstract: Guidelines and Expert Consensus documents aim to present all the relevant evidence on a particular issue in order to help physicians to weigh the benefits and risks of a particular diagnostic or therapeutic procedure. They should be helpful in everyday clinical decision-making. A great number of Guidelines and Expert Consensus Documents have been issued in recent years by different organisations, the European Society of Cardiology (ESC) and by other related societies. By means of links to web sites of National Societies several hundred guidelines are available. This profusion can put at stake the authority and validity of guidelines, which can only be guaranteed if they have been developed by an unquestionable decision-making process. This is one of the reasons why the ESC and others have issued recommendations for formulating and issuing Guidelines and Expert Consensus Documents. In spite of the fact that standards for issuing good quality Guidelines and Expert Consensus Documents are well defined, recent surveys of Guidelines and Expert Consensus Documents published in peer-reviewed journals between 1985 and 1998 have shown that methodological standards were not complied within the vast majority of cases. It is therefore of great importance that guidelines and recommendations are presented in formats that are easily interpreted. Subsequently, their implementation programmes must also be well conducted. Attempts have been made to determine whether guidelines improve the quality of clinical practice and the utilisation of health resources. The ESC Committee for Practice Guidelines ( CPG ) supervises and coordinates the preparation of new Guidelines and Expert Consensus Documents produced by Task Forces, expert groups or consensus panels. The Committee is also responsible for the endorsement of these Guidelines and Expert Consensus Documents or statements. The strength of evidence related to a particular diagnostic or treatment option depends on the available data: (1) level of evidence A: multiple …

1,208 citations


Journal ArticleDOI
28 Jul 2004-JAMA
TL;DR: RANKL blockade has prevented bone loss caused by osteoporosis, chronic inflammatory disorders, and malignant tumors in animal models and may emerge as a therapy in humans based on studies in postmenopausal osteop orosis, myeloma bone disease, and osteolytic metastases.
Abstract: Bone resorption by osteoclasts is coupled with bone formation by osteoblasts, and this balanced process continuously remodels and adapts the skeleton. The receptor activator of nuclear factor kappaB ligand (RANKL) has been identified as an essential cytokine for the formation and activation of osteoclasts. The effects of RANKL are physiologically counterbalanced by the decoy receptor osteoprotegerin (OPG). Estrogen deficiency, glucocorticoid exposure, T-cell activation (eg, rheumatoid arthritis), and skeletal malignancies (eg, myeloma, metastases) enhance the ratio of RANKL to OPG and, thus, promote osteoclastogenesis, accelerate bone resorption, and induce bone loss. Moreover, alterations of the OPG/RANKL/RANK system have been implicated in vascular diseases. RANKL blockade (using OPG or RANK fusion proteins or RANKL antibodies) has prevented bone loss caused by osteoporosis, chronic inflammatory disorders, and malignant tumors in animal models and may emerge as a therapy in humans based on studies in postmenopausal osteoporosis, myeloma bone disease, and osteolytic metastases. This review summarizes the clinical implications of the OPG/RANKL/RANK system for bone and vascular diseases.

916 citations


Journal ArticleDOI
TL;DR: In this article, the authors provided ultrastructural evidence showing that highly proliferative precursors in the adult subependymal zone express dopamine receptors and receive dopaminergic afferents.
Abstract: Cerebral dopamine depletion is the hallmark of Parkinson disease. Because dopamine modulates ontogenetic neurogenesis, depletion of dopamine might affect neural precursors in the subependymal zone and subgranular zone of the adult brain. Here we provide ultrastructural evidence showing that highly proliferative precursors in the adult subependymal zone express dopamine receptors and receive dopaminergic afferents. Experimental depletion of dopamine in rodents decreases precursor cell proliferation in both the subependymal zone and the subgranular zone. Proliferation is restored completely by a selective agonist of D2-like (D2L) receptors. Experiments with neural precursors from the adult subependymal zone grown as neurosphere cultures confirm that activation of D2L receptors directly increases the proliferation of these precursors. Consistently, the numbers of proliferating cells in the subependymal zone and neural precursor cells in the subgranular zone and olfactory bulb are reduced in postmortem brains of individuals with Parkinson disease. These observations suggest that the generation of neural precursor cells is impaired in Parkinson disease as a consequence of dopaminergic denervation.

912 citations


Journal ArticleDOI
TL;DR: It is demonstrated that influenza viruses enter the airway epithelium through specific target cells and that there were striking differences in this respect between human and avian viruses.
Abstract: The recent human infections caused by H5N1, H9N2, and H7N7 avian influenza viruses highlighted the continuous threat of new pathogenic influenza viruses emerging from a natural reservoir in birds. It is generally believed that replication of avian influenza viruses in humans is restricted by a poor fit of these viruses to cellular receptors and extracellular inhibitors in the human respiratory tract. However, detailed mechanisms of this restriction remain obscure. Here, using cultures of differentiated human airway epithelial cells, we demonstrated that influenza viruses enter the airway epithelium through specific target cells and that there were striking differences in this respect between human and avian viruses. During the course of a single-cycle infection, human viruses preferentially infected nonciliated cells, whereas avian viruses as well as the egg-adapted human virus variant with an avian virus-like receptor specificity mainly infected ciliated cells. This pattern correlated with the predominant localization of receptors for human viruses (2-6-linked sialic acids) on nonciliated cells and of receptors for avian viruses (2-3-linked sialic acids) on ciliated cells. These findings suggest that although avian influenza viruses can infect human airway epithelium, their replication may be limited by a nonoptimal cellular tropism. Our data throw light on the mechanisms of generation of pandemic viruses from their avian progenitors and open avenues for cell level-oriented studies on the replication and pathogenicity of influenza virus in humans.

746 citations


Journal ArticleDOI
TL;DR: It is demonstrated that viral NA plays a role early in infection, and they provide further rationale for the prophylactic use of NA inhibitors.
Abstract: Influenza virus neuraminidase (NA) plays an essential role in release and spread of progeny virions, following the intracellular viral replication cycle. To test whether NA could also facilitate virus entry into cell, we infected cultures of human airway epithelium with human and avian influenza viruses in the presence of the NA inhibitor oseltamivir carboxylate. Twenty- to 500-fold less cells became infected in drug-treated versus nontreated cultures (P < 0.0001) 7 h after virus application, indicating that the drug suppressed the initiation of infection. These data demonstrate that viral NA plays a role early in infection, and they provide further rationale for the prophylactic use of NA inhibitors.

573 citations


Journal ArticleDOI
TL;DR: The observation that respiratory infections are nevertheless rare is testimony to the presence of an efficient host defence system at the mucosal surface of the lung, and the importance of these peptides as effector molecules of innate immunity by killing microorganisms, but also as regulators of inflammation, immunity and wound repair is indicated.
Abstract: The human lung is exposed to a large number of airborne pathogens as a result of the daily inhalation of 10,000 litres of air. The observation that respiratory infections are nevertheless rare is testimony to the presence of an efficient host defence system at the mucosal surface of the lung. The airway epithelium is strategically positioned at the interface with the environment, and thus plays a key role in this host defence system. Recognition systems employed by airway epithelial cells to respond to microbial exposure include the action of the toll-like receptors. The airway epithelium responds to such exposure by increasing its production of mediators such as cytokines, chemokines and antimicrobial peptides. Recent findings indicate the importance of these peptides as effector molecules of innate immunity by killing microorganisms, but also as regulators of inflammation, immunity and wound repair. Finally, the clinical relevance of the functions of the airway epithelium in innate immunity is discussed.

564 citations


Posted Content
TL;DR: In this paper, the authors propose that the relationship between identification and turnover will be mediated by job satisfaction as the more specific evaluation of one's task and working conditions, which in turn predicts turnover intentions.
Abstract: The social identity approach is a powerful theoretical framework for the understanding of individuals' behaviour. The main argument is that individuals think and act on behalf of the group they belong to because this group membership adds to their social identity, which partly determines one's self-esteem. In the organizational world, social identity and self-categorization theories state that a strong organizational identification is associated with low turnover intentions. Because identification is the more general perception of shared fate between employee and organization, we propose that the relationship between identification and turnover will be mediated by job satisfaction as the more specific evaluation of one's task and working conditions. In four samples we found organizational identification feeding into job satisfaction, which in turn predicts turnover intentions.

545 citations


Journal ArticleDOI
TL;DR: In this article, the authors propose that the relationship between identification and turnover will be mediated by job satisfaction as the more specific evaluation of ones task and working conditions, which in turn predicts turnover intentions.
Abstract: The social identity approach is a powerful theoretical framework for the understanding of individuals behaviour The main argument is that individuals think and act on behalf of the group they belong to because this group membership adds to their social identity, which partly determines ones self-esteem In the organizational world, social identity and self-categorization theories state that a strong organizational identification is associated with low turnover intentions Because identification is the more general perception of shared fate between employee and organization, we propose that the relationship between identification and turnover will be mediated by job satisfaction as the more specific evaluation of ones task and working conditions In four samples we found organizational identification feeding into job satisfaction, which in turn predicts turnover intentions

501 citations


Journal ArticleDOI
TL;DR: In this article, predictions of social identity and self-categorization theories about the relevance of social identification in organizational contexts are presented, and different foci of identification (eg with own career, team, organization, occupation) as well as different dimensions of organizational identification (cognitive, affective, evaluative, and behavioural) can be separated.
Abstract: Predictions of social identity and self-categorization theories about the relevance of social identification in organizational contexts are presented We propose that different foci of identification (eg with own career, team, organization, occupation) as well as different dimensions of organizational identification (cognitive, affective, evaluative, and behavioural) can be separated Furthermore, these different aspects of organizational identification are assumed to be differentially associated with work-related attitudes and behaviours Predictions are first tested in a questionnaire study of 515 German school teachers Confirmatory factor analyses demonstrated that dimensions and foci can indeed be differentiated In addition, results indicate that different aspects correlate differentially with different criteria The results are cross-validated in two samples of 233 German school teachers and 358 bank accountants, respectively

458 citations


Journal ArticleDOI
10 Sep 2004-Science
TL;DR: Experimental observation of unstable traveling waves in pipe flow is reported, confirming the proposed transition scenario and suggesting that the dynamics associated with these unstable states may indeed capture the nature of fluid turbulence.
Abstract: Transition to turbulence in pipe flow is one of the most fundamental and longest-standing problems in fluid dynamics. Stability theory suggests that the flow remains laminar for all flow rates, but in practice pipe flow becomes turbulent even at moderate speeds. This transition drastically affects the transport efficiency of mass, momentum, and heat. On the basis of the recent discovery of unstable traveling waves in computational studies of the Navier-Stokes equations and ideas from dynamical systems theory, a model for the transition process has been suggested. We report experimental observation of these traveling waves in pipe flow, confirming the proposed transition scenario and suggesting that the dynamics associated with these unstable states may indeed capture the nature of fluid turbulence.

Journal ArticleDOI
17 Nov 2004-Brain
TL;DR: It is shown that RBD patients have a profound impairment of olfactory function, which correlates with the neuropathological staging of Parkinson's disease (stages 1-3) as proposed by Braak.
Abstract: REM sleep behaviour disorder (RBD) and olfactory dysfunction are common and very early features of alpha-synucleinopathies, in particular Parkinson's disease. To investigate the hypothesis that these two clinical features in combination are an indicator of evolving alpha-synucleinopathy, olfactory function was assessed in RBD. We studied 30 patients (18 male, 12 female; mean age 48 +/- 14 years, range 19-78 years) with clinical (idiopathic, n = 6; symptomatic, n = 13, mostly associated with narcolepsy) or subclinical (n = 11, associated with narcolepsy) RBD according to standard criteria and 30 age- and gender-matched healthy control subjects using standardized 'Sniffin' Sticks'. RBD patients had a significantly higher olfactory threshold (P = 0.0001), lower discrimination score (P = 0.003), and lower identification score (P = 0.001). Compared with normative data, 97% of the RBD patients had a pathologically increased olfactory threshold, 63% an impaired odour discrimination score, and 63% a decreased identification score. On neurological examination, signs of parkinsonism were newly found in five patients with clinical RBD (not associated with narcolepsy), who usually had a long history of 'idiopathic' RBD. Four of the five patients fulfilled the UK Brain Bank criteria for the clinical diagnosis of Parkinson's disease. The underlying nigrostriatal degeneration of clinical Parkinson's disease was confirmed by I-123-FP-CIT SPECT in one patient and early nigrostriatal degeneration was identified by SPECT in a further two patients with 'idiopathic' clinical RBD out of 11 RBD patients who agreed to undergo SPECT studies. Our study shows that RBD patients have a profound impairment of olfactory function. Five patients with clinical RBD not associated with narcolepsy had clinical or imaging signs of nigrostriatal degeneration. This new clinical finding correlates with the neuropathological staging of Parkinson's disease (stages 1-3) as proposed by Braak. In stage 1, the anterior olfactory nucleus or the olfactory bulb is affected (along with the dorsal motor nucleus of the glossopharyngeal and vagal nerves). In stage 2, additional lesions consistently remain confined to the medulla oblongata and pontine tegmentum, which are critical areas for RBD. Midbrain lesions are found only in stage 3, in particular degeneration of dopaminergic neurons in the substantia nigra pars compacta. Thus, 'idiopathic' RBD patients with olfactory impairment might present with stage 2 preclinical alpha-synucleinopathy. Since narcoleptic patients are not known to have an increased risk of developing parkinsonism, the pathophysiology and clinical relevance of hyposmia in RBD/narcolepsy patients requires further research.

Journal ArticleDOI
TL;DR: Interestingly, the ability of these nanoparticles to provide improved access to the associated antigen to the immune system was not significantly affected by the CS Mw, and high and long-lasting responses could be obtained using low Mw CS molecules.

Journal ArticleDOI
TL;DR: An unexpected nanomolar affinity is demonstrated of the COX-2 specific arylsulfonamide-type celecoxib and valdecoxib for isoenzymes of the totally unrelated carbonic anhydrase (CA) family, such as CA I, II, IV, and IX, whereas the rofecoxib methyl sulfone-type has no effect.
Abstract: By optimizing binding to a selected target protein, modern drug research strives to develop safe and efficacious agents for the treatment of disease. Selective drug action is intended to minimize undesirable side effects from scatter pharmacology. Celecoxib (Celebrex), valdecoxib (Bextra), and rofecoxib (Vioxx) are nonsteroidal antiinflammatory drugs (NSAIDs) due to selective inhibition of inducible cyclooxygenase COX-2 while sparing inhibition of constitutive COX-1. While rofecoxib contains a methyl sulfone constituent, celecoxib and valdecoxib possess an unsubstituted arylsulfonamide moiety. The latter group is common to many carbonic anhydrase (CA) inhibitors. Using enzyme kinetics and X-ray crystallography, we demonstrate an unexpected nanomolar affinity of the COX-2 specific arylsulfonamide-type celecoxib and valdecoxib for isoenzymes of the totally unrelated carbonic anhydrase (CA) family, such as CA I, II, IV, and IX, whereas the rofecoxib methyl sulfone-type has no effect. When administered orally to glaucomatous rabbits, celecoxib and valdecoxib lowered intraocular pressure, suggesting that these agents may have utility in the treatment of this disorder. The crystal structure of celecoxib in complex with CA II reveals part of this inhibition to be mediated via binding of the sulfonamide group to the catalytic zinc of CA II. To investigate the structural basis for cross-reactivity of these compounds between COX-2 and CA II, we compared the molecular recognition properties of both protein binding pockets in terms of local physicochemical similarities among binding site-exposed amino acids accommodating different portions of the drug molecules. Our approach Cavbase, implemented into Relibase, detects similarities between the sites, suggesting some potential to predict unexpected cross-reactivity of drugs among functionally unrelated target proteins. The observed cross-reactivity with CAs may also contribute to differences in the pharmacological profiles, in particular with respect to glaucoma and anticancer therapy and may suggest new opportunities of these COX-2 selective NSAIDs.

Journal ArticleDOI
TL;DR: In this paper, the wetting of porous templates with polymer melts and solutions or polymer-containing mixtures is a simple and versatile method for the preparation of tubular structures with diameters ranging from a few tens of nanometers to micrometers.
Abstract: The wetting of porous templates with polymer melts and solutions or polymer-containing mixtures is a simple and versatile method for the preparation of tubular structures with diameters ranging from a few tens of nanometers to micrometers. The tube walls can be made of a multitude of materials, some of which have thus far been altogether impossible to use or very limited in their ability to be incorporated into nanostuctures. Template wetting also makes it possible to modify the nanotubes in a variety of ways, for example through the controlled generation of pores or the embedding of nanoparticles into the walls. This method offers a promising approach to functionalized nanotube-template hybrid systems and free-standing nanotubes.

Journal ArticleDOI
TL;DR: Various strategies used for the preparation of in situ forming parenteral drug depots and their potential benefits/draw-backs are reviewed, especially with regard to the delivery of protein drug candidates.

Journal ArticleDOI
29 Oct 2004-Science
TL;DR: Comparative analysis indicates that both types of photoreceptors, with distinct opsins, coexisted in Urbilateria, the last common ancestor of insects and vertebrates, and sheds new light on vertebrate eye evolution.
Abstract: For vision, insect and vertebrate eyes use rhabdomeric and ciliary photoreceptor cells, respectively. These cells show distinct architecture and transduce the light signal by different phototransductory cascades. In the marine rag-worm Platynereis, we find both cell types: rhabdomeric photoreceptor cells in the eyes and ciliary photoreceptor cells in the brain. The latter use a photopigment closely related to vertebrate rod and cone opsins. Comparative analysis indicates that both types of photoreceptors, with distinct opsins, coexisted in Urbilateria, the last common ancestor of insects and vertebrates, and sheds new light on vertebrate eye evolution.

Journal ArticleDOI
TL;DR: In this article, an accurate determination of surface-state linewidth by scanning tunneling spectroscopy, photoemission and directly in the time domain by two-photon photo-emission is presented.

Journal ArticleDOI
03 Dec 2004-Science
TL;DR: The crystal structure of a DNA photolyase bound to duplex DNA that is bent by 50° and comprises a synthetic CPD lesion that apparently mimics a structural substate during light-driven DNA repair in which back-flipping of the thymines into duplexDNA has not yet taken place is reported.
Abstract: DNA photolyases use light energy to repair DNA that comprises ultraviolet-induced lesions such as the cis-syn cyclobutane pyrimidine dimers (CPDs). Here we report the crystal structure of a DNA photolyase bound to duplex DNA that is bent by 50 degrees and comprises a synthetic CPD lesion. This CPD lesion is flipped into the active site and split there into two thymines by synchrotron radiation at 100 K. Although photolyases catalyze blue light-driven CPD cleavage only above 200 K, this structure apparently mimics a structural substate during light-driven DNA repair in which back-flipping of the thymines into duplex DNA has not yet taken place.

Journal ArticleDOI
TL;DR: Evidence is provided for a more detailed investigation of IVIgG for the treatment of AD as evidence for active or passive immunisation can mitigate plaque pathology in murine models of Alzheimer's disease.
Abstract: Objective: Active or passive immunisation can mitigate plaque pathology in murine models of Alzheimer’s disease (AD). Recently, it has been shown that antibodies against b-amyloid (Ab) are present in human immunoglobulin preparations (IVIgG), which specifically recognise and inhibit the neurotoxic effects of Ab. This study reports the results from a pilot study using IVIgG in patients with AD. Methods: Five patients with AD were enrolled and received monthly IVIgG over a 6 month period. Efficacy assessment included total Ab/Ab1–42 measured in the CSF/serum as well as effects on cognition (ADAS-cog; CERAD) at baseline and at 6 months following IVIgG. Results: Following IVIgG, total Ab levels in the CSF decreased by 30.1% (17.3–43.5%) compared to baseline (p,0.05). Total Ab increased in the serum by 233% (p,0.05). No significant change was found in Ab1–42 levels in the CSF/serum. Using ADAS-cog, an improvement of 3.7i2.9 points was detected. Scores in the MMSE were essentially unchanged (improved in four patients, stable in one patient) following IVIgG compared to baseline. Conclusion: Although the sample size of this pilot study is too small to draw a clear conclusion, the results of this pilot study provide evidence for a more detailed investigation of IVIgG for the treatment of AD.

Journal ArticleDOI
TL;DR: Investigation of factors affecting the oxidative depolymerization of chitosan and physicochemical properties of the resulting polymer fractions including their cytotoxicity found low molecular weight fractions of ch itosan may potentially useful for the design of drug delivery systems due to the improved solubility properties.

Journal ArticleDOI
TL;DR: DC-SIGN and DC-SIGNR enhance infection mediated by the glycoprotein of Marburg virus and the S protein of severe acute respiratory syndrome coronavirus and might promote viral dissemination.
Abstract: The lectins DC-SIGN and DC-SIGNR can augment viral infection; however, the range of pathogens interacting with these attachment factors is incompletely defined. Here we show that DC-SIGN and DC-SIGNR enhance infection mediated by the glycoprotein (GP) of Marburg virus (MARV) and the S protein of severe acute respiratory syndrome coronavirus and might promote viral dissemination. SIGNR1, a murine DC-SIGN homologue, also enhanced infection driven by MARV and Ebola virus GP and could be targeted to assess the role of attachment factors in filovirus infection in vivo.

Journal ArticleDOI
TL;DR: A critical role of childhood vision is suggested in modulating the perception of touch that may arise from the emergence of specific crossmodal links during development as well as the first empirical evidence for superior temporal order judgments for tactile stimuli in the congenitally blind.

Journal ArticleDOI
TL;DR: The naturally occurring S141L TRPM 6 missense mutation abrogated the oligomeric assembly of TRPM6, thus providing a cell biological explanation for the human disease.
Abstract: Impaired magnesium reabsorption in patients with TRPM6 gene mutations stresses an important role of TRPM6 (melastatin-related TRP cation channel) in epithelial magnesium transport. While attempting to isolate full-length TRPM6, we found that the human TRPM6 gene encodes multiple mRNA isoforms. Full-length TRPM6 variants failed to form functional channel complexes because they were retained intracellularly on heterologous expression in HEK 293 cells and Xenopus oocytes. However, TRPM6 specifically interacted with its closest homolog, the Mg2+-permeable cation channel TRPM7, resulting in the assembly of functional TRPM6/TRPM7 complexes at the cell surface. The naturally occurring S141L TRPM6 missense mutation abrogated the oligomeric assembly of TRPM6, thus providing a cell biological explanation for the human disease. Together, our data suggest an important contribution of TRPM6/TRPM7 heterooligomerization for the biological role of TRPM6 in epithelial magnesium absorption.

Journal ArticleDOI
01 Jun 2004-Oikos
TL;DR: It is concluded that the extinction of populations was at least partly due to stochastic processes, supported by the fact that in allspecies a considerable proportion of small populations survived and developed intolarge populations.
Abstract: 488.Due to habitat fragmentation many plant species today occur mainly in small andisolated populations. Modeling studies predict that small populations will bethreatened more strongly by stochastic processes than large populations, but there islittle empirical evidence to support this prediction for plants. We studied therelationship between size of local populations (number of flowering plants) andsurvival over ten years for 359 populations of eight short-lived, threatened plants innorthern Germany (Lepidium campestre, Thlaspi perfoliatum, Rhinanthus minor, R.serotinus, Melampyrum arvense, M. nemorosum, Gentianella ciliata and G.germanica). Overall, 27% of the populations became extinct during the study period.Probability of survival of a local population increased significantly with its size in allbut one species (R. minor). However, estimated population sizes required for 90%probability of survival over 10 years varied widely among species. Survival probabilityincreased with decreasing distance to the nearest conspecific population in R. serotinus,but not in the other species. The mean annual growth rate of surviving populationsdiffered greatly between species, but was only for G. germanica significantly lower than1, suggesting that there was no general deterministic decline in the number of plantsdue to deteriorating habitat conditions. We conclude that the extinction of populationswas at least partly due to stochastic processes. This is supported by the fact that in allspecies a considerable proportion of small populations survived and developed intolarge populations.D. Matthies, Plant Ecology, Dept of Biology, Univ. of Marburg, DE-35032 Marburg,Germany (matthies@staff.uni-marburg.de).

Journal ArticleDOI
TL;DR: A systematic review of psychological and psychosocial predictors of weight loss and mental health after bariatric surgery found psychiatric comorbidity seems to be of more predictive value for mental and physical well-being as two essential aspects of quality of life than for weight loss postsurgery.
Abstract: HERPERTZ, S., R. KIELMANN, A.M. WOLF, J. HEBEBRAND, AND W. SENF. Do psychosocial variables predict weight loss or mental health after obesity surgery? A systematic review. Obes Res. 2004;12:1554–1569. Objective: The objective of this study was to present a systematic review of psychological and psychosocial predictors of weight loss and mental health after bariatric surgery. This systematic review included all controlled and noncontrolled trials of the last 2 decades with either a retrospective or prospective design and a follow-up period of at least 1 year. Research Methods and Procedures: The relevant literature was identified by a search of computerized databases. All articles published in English and German between 1980 and 2002 were reviewed. Results: Using the above inclusion/exclusion criteria, 29 articles were identified focusing on psychosocial predictors of weight loss and mental health after obesity surgery. Discussion: Personality traits have no predictive value for the postoperative course of weight or mental state. Apart from serious psychiatric disorders including personality disorders, psychiatric comorbidity seems to be of more predictive value for mental and physical well-being as two essential aspects of quality of life than for weight loss postsurgery. However, depressive and anxiety symptoms as correlates of psychological stress with regard to obesity seem to be positive predictors of weight loss postsurgery. The severity of the symptoms or the disorder is more relevant for the outcome of obesity surgery than the specificity of the symptoms. It is also not solely the consumption of distinct “forbidden” foods, such as sweets or soft drinks, but rather a general hypercaloric eating behavior, either as an expression of the patient’s inadequate compliance or a dysregulation in energy balance, which is associated with a poor weight loss postsurgery.

Journal ArticleDOI
TL;DR: The data suggest that the recombinant VSV can be used to study the role of the viral glycoproteins in virus replication, immune response, and pathogenesis and none of the rVSVs displayed pathogenic potential in animals.
Abstract: Replication-competent recombinant vesicular stomatitis viruses (rVSVs) expressing the type I transmembrane glycoproteins and selected soluble glycoproteins of several viral hemorrhagic fever agents (Marburg virus, Ebola virus, and Lassa virus) were generated and characterized. All recombinant viruses exhibited rhabdovirus morphology and replicated cytolytically in tissue culture. Unlike the rVSVs with an additional transcription unit expressing the soluble glycoproteins, the viruses carrying the foreign transmembrane glycoproteins in replacement of the VSV glycoprotein were slightly attenuated in growth. Biosynthesis and processing of the foreign glycoproteins were authentic, and the cell tropism was defined by the transmembrane glycoprotein. None of the rVSVs displayed pathogenic potential in animals. The rVSV expressing the Zaire Ebola virus transmembrane glycoprotein mediated protection in mice against a lethal Zaire Ebola virus challenge. Our data suggest that the recombinant VSV can be used to study the role of the viral glycoproteins in virus replication, immune response, and pathogenesis.

Journal ArticleDOI
TL;DR: The data suggest that PV can be predicted with an acceptable accuracy using a four-item simplified risk score, and a simple score to predict PV in children (POVOC-score) is developed and validated.
Abstract: Risk scores to predict the occurrence of postoperative vomiting (PV) or nausea and vomiting that were developed for adult patients do not fit for children, because several risk factors are difficult to assess or are usually not applicable in pediatric patients (e.g., smoking status). Thus, in the present study, we sought to develop and to validate a simple score to predict PV in children (POVOC-score). Development and validation of the new score was based on data from 4 independent institutions of 1257 children (aged 0-14 yr) undergoing various types of surgery under general anesthesia without antiemetic prophylaxis. Preoperatively, several potential risk factors were recorded. Postoperatively, the occurrence of PV was observed for up to 24 h. The dataset was randomly split into an evaluation set (n = 657) that was analyzed using a forward logistic regression technique and a validation set (n = 600) that was used to confirm the accuracy of prediction by means of the area under a receiver operating characteristic curve. Four independent risk factors for PV were identified in the final analysis: duration of surgery >/=30 min, age >/=3 yr, strabismus surgery, and a positive history of PV in the children or PV/postoperative nausea and vomiting in relatives (mother, father, or siblings). The incidence of PV was 9%, 10%, 30%, 55%, and 70% for 0, 1, 2, 3, and 4 risk factors observed. Using these incidences as cut-off values in the validation dataset, the area under the receiver operating characteristic curve was 0.72 (95% confidence interval: 0.68-0.77). Our data suggest that PV can be predicted with an acceptable accuracy using a four-item simplified risk score.

Journal ArticleDOI
TL;DR: This work investigates the expressiveness and complexity of the automata and their connection to the logics, as well as standard decision problems of Kaminski and Francez on register automata.
Abstract: Motivated by formal models recently proposed in the context of XML, we study automata and logics on strings over infinite alphabets. These are conservative extensions of classical automata and logics defining the regular languages on finite alphabets. Specifically, we consider register and pebble automata, and extensions of first-order logic and monadic second-order logic. For each type of automaton we consider one-way and two-way variants, as well as deterministic, nondeterministic, and alternating control. We investigate the expressiveness and complexity of the automata and their connection to the logics, as well as standard decision problems. Some of our results answer open questions of Kaminski and Francez on register automata.

Journal ArticleDOI
TL;DR: The proteome of growing cells of Bacillus subtilis was analyzed and a reasonable correlation was found for the majority of protein spots, and the vegetative proteome containing 876 proteins in total is now ready for physiological applications.
Abstract: The proteome of growing cells of Bacillus subtilis was analyzed in order to provide the basis for its application in microbial physiology. DNA arrays were used to calculate the number of genes transcribed in growing cells. From the 4100 B. subtilis genes, 2515 were actively transcribed in cells grown under standard conditions. From these genes 1544 proteins should be covered by our standard gel system pI 4-7. Using this standard gel system and supplementary zoom gels (pI 5.5-6.7, 5-6, 4.5-5.5, and 4-5) 693 proteins which are expressed in growing cells were detected that cover more than 40% of the vegetative proteome predicted for this region. Particularly broad coverage and thus comprehensive monitoring will be possible for central carbohydrate metabolism (glycolysis, pentose phosphate shunt, and citric acid cycle), amino acid synthesis pathways, purine and pyrimidine metabolism, fatty acid metabolism, and main cellular functions like replication, transcription, translation, and cell wall synthesis. Comparing the theoretical pI and Mr values with those experimentally determined a reasonable correlation was found for the majority of protein spots. By a color code outliers with dramatic deviations in charge or mass were visualized that may indicate post-translational modifications. In addition to the cytosolic neutral and alkaline proteins, 130 membrane proteins were found relying on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) separation in combination with electrospray ionization-tandem mass spectrometry (ESI-MS/MS) techniques. The vegetative proteome containing 876 proteins in total is now ready for physiological applications. Two main proteome fractions (pI 4-7 and zoom gel pI 4.5-5.5) should be sufficient for such high-throughput physiological proteomics.