81 resultados para Extent and limit of quotas
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BACKGROUND Aeromonas salmonicida subsp. salmonicida, the etiologic agent of furunculosis, is a major pathogen of fisheries worldwide. Several virulence factors have been described, but the type-three secretion system (T3SS) is recognized as having a major effect on virulence by injecting effectors directly into fish cells. In this study we used high-throughput proteomics to display the differences between in vitro secretome of A. salmonicida wild-type (wt, hypervirulent, JF2267) and T3SS-deficient (isogenic ΔascV, extremely low-virulent, JF2747) strains in exponential and stationary phases of growth. RESULTS Results confirmed the secretion of effectors AopH, AexT, AopP and AopO via T3SS, and for the first time demonstrated the impact of T3SS in secretion of Ati2, AopN and ExsE that are known as effectors in other pathogens. Translocators, needle subunits, Ati1, and AscX were also secreted in supernatants (SNs) dependent on T3SS. AopH, Ati2, AexT, AopB and AopD were in the top seven most abundant excreted proteins. EF-G, EF-Tu, DnaK, HtpG, PNPase, PepN and MdeA were moderately secreted in wt SNs and predicted to be putative T3 effectors by bioinformatics. Pta and ASA_P5G088 were increased in wt SNs and T3-associated in other bacteria. Ten conserved cytoplasmic proteins were more abundant in wt SNs than in the ΔascV mutant, but without any clear association to a secretion system. T1-secreted proteins were predominantly found in wt SNs: OmpAI, OmpK40, DegQ, insulinase ASA_0716, hypothetical ASA_0852 and ASA_3619. Presence of T3SS components in pellets was clearly decreased by ascV deletion, while no impact was observed on T1- and T2SS. Our results demonstrated that the ΔascV mutant strain excreted well-described (VapA, AerA, AerB, GCAT, Pla1, PlaC, TagA, Ahe2, GbpA and enolase) and yet uncharacterized potential toxins, adhesins and enzymes as much as or even more than the wt strain. Other putative important virulence factors were not detected. CONCLUSIONS We demonstrated the whole in vitro secretome and T3SS repertoire of hypervirulent A. salmonicida. Several toxins, adhesins and enzymes that are not part of the T3SS secretome were secreted to a higher extent in the extremely low-virulent ΔascV mutant. All together, our results show the high importance of an intact T3SS to initiate the furunculosis and offer new information about the pathogenesis.
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Bilingual education programs implicitly assume that the acquired knowledge is represented in a language-independent way. This assumption, however, stands in strong contrast to research findings showing that information may be represented in a way closely tied to the specific language of instruction and learning. The present study aims to examine whether and to which extent cognitive costs appear during arithmetic learning when language of instruction and language of retrieving differ. Thirty-nine high school students participating in a bilingual education program underwent a four-day training on multiplication and subtraction problems in one language (German or French), followed by a test session in which they had to solve trained as well as untrained problems in both languages. We found that cognitive costs related to language switching appeared for both arithmetic operations. Implications of our findings are discussed with respect to bilingual education as well as to cognitive mechanisms underlying different arithmetic operations.
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BACKGROUND Randomized control trials (RCTs) stopped early for benefit (truncated RCTs) are increasingly common and, on average, overestimate the relative magnitude of benefit by approximately 30%. Investigators stop trials early when they consider it is no longer ethical to enroll patients in a control group. The goal of this systematic review is to determine how investigators of ongoing or planned RCTs respond to the publication of a truncated RCT addressing a similar question. METHODS/DESIGN We will conduct systematic reviews to update the searches of 210 truncated RCTs to identify similar trials ongoing at the time of publication, or started subsequently, to the truncated trials ('subsequent RCTs'). Reviewers will determine in duplicate the similarity between the truncated and subsequent trials. We will analyze the epidemiology, distribution, and predictors of subsequent RCTs. We will also contact authors of subsequent trials to determine reasons for beginning, continuing, or prematurely discontinuing their own trials, and the extent to which they rely on the estimates from truncated trials. DISCUSSION To the extent that investigators begin or continue subsequent trials they implicitly disagree with the decision to stop the truncated RCT because of an ethical mandate to administer the experimental treatment. The results of this study will help guide future decisions about when to stop RCTs early for benefit.
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Scholars have increasingly theorized, and debated, the decision by states to create and delegate authority to international courts, as well as the subsequent autonomy and behavior of those courts, with principal–agent and trusteeship models disagreeing on the nature and extent of states’ influence on international judges. This article formulates and tests a set of principal–agent hypotheses about the ways in which, and the conditions under which, member states are able use their powers of judicial nomination and appointment to influence the endogenous preferences of international judges. The empirical analysis surveys the record of all judicial appointments to the Appellate Body (AB) of the World Trade Organization over a 15-year period. We present a view of an AB appointment process that, far from representing a pure search for expertise, is deeply politicized and offers member-state principals opportunities to influence AB members ex ante and possibly ex post. We further demonstrate that the AB nomination process has become progressively more politicized over time as member states, responding to earlier and controversial AB decisions, became far more concerned about judicial activism and more interested in the substantive opinions of AB candidates, systematically championing candidates whose views on key issues most closely approached their own, and opposing candidates perceived to be activist or biased against their substantive preferences. Although specific to the WTO, our theory and findings have implications for the judicial politics of a large variety of global and regional international courts and tribunals.
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Resting endothelial cells express the small proteoglycan biglycan, whereas sprouting endothelial cells also synthesize decorin, a related proteoglycan. Here we show that decorin is expressed in endothelial cells in human granulomatous tissue. For in vitro investigations, the human endothelium-derived cell line, EA.hy 926, was cultured for 6 or more days in the presence of 1% fetal calf serum on top of or within floating collagen lattices which were also populated by a small number of rat fibroblasts. Endothelial cells aligned in cord-like structures and developed cavities that were surrounded by human decorin. About 14% and 20% of endothelial cells became apoptotic after 6 and 12 days of co-culture, respectively. In the absence of fibroblasts, however, the extent of apoptosis was about 60% after 12 days, and cord-like structures were not formed nor could decorin production be induced. This was also the case when lattices populated by EA.hy 926 cells were maintained under one of the following conditions: 1) 10% fetal calf serum; 2) fibroblast-conditioned media; 3) exogenous decorin; or 4) treatment with individual growth factors known to be involved in angiogenesis. The mechanism(s) by which fibroblasts induce an angiogenic phenotype in EA.hy 926 cells is (are) not known, but a causal relationship between decorin expression and endothelial cell phenotype was suggested by transducing human decorin cDNA into EA.hy 926 cells using a replication-deficient adenovirus. When the transduced cells were cultured in collagen lattices, there was no requirement of fibroblasts for the formation of capillary-like structures and apoptosis was reduced. Thus, decorin expression seems to be of special importance for the survival of EA.hy 926 cells as well as for cord and tube formation in this angiogenesis model.
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In the genus Petunia, distinct pollination syndromes may have evolved in association with bee-visitation (P. integrifolia spp.) or hawk moth-visitation (P. axillaris spp). We investigated the extent of congruence between floral fragrance and olfactory perception of the hawk moth Manduca sexta. Hawk moth pollinated P. axillaris releases high levels of several compounds compared to the bee-pollinated P. integrifolia that releases benzaldehyde almost exclusively. The three dominating compounds in P. axillaris were benzaldehyde, benzyl alcohol and methyl benzoate. In P. axillaris, benzenoids showed a circadian rhythm with an emission peak at night, which was absent from P. integrifolia. These characters were highly conserved among different P. axillaris subspecies and P. axillaris accessions, with some differences in fragrance composition. Electroantennogram (EAG) recordings using flower-blends of different wild Petunia species on female M. sexta antennae showed that P. axillaris odours elicited stronger responses than P. integrifolia odours. EAG responses were highest to the three dominating compounds in the P. axillaris flower odours. Further, EAG responses to odour-samples collected from P. axillaris flowers confirmed that odours collected at night evoked stronger responses from M. sexta than odours collected during the day. These results show that timing of odour emissions by P. axillaris is in tune with nocturnal hawk moth activity and that flower-volatile composition is adapted to the antennal perception of these pollinators.
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OBJECTIVE The aim of the study was to describe the (a) symptom experience of women with vulvar intraepithelial neoplasia and vulvar cancer (vulvar neoplasia) during the first week after hospital discharge, and (b) associations between age, type of disease, stage of disease, the extent of surgical treatment and symptom experience. METHODS This cross-sectional study was conducted in eight hospitals in Germany and Switzerland (Clinical Trial ID: NCT01300663). Symptom experience after surgical treatment in women with vulvar neoplasia was measured with our newly developed WOMAN-PRO instrument. Outpatients (n=65) rated 31 items. We used descriptive statistics and regression analysis. RESULTS The average number of symptoms reported per patient was 20.2 (SD 5.77) with a range of 5 to 31 symptoms. The three most prevalent wound-related symptoms were 'swelling' (n=56), 'drainage' (n=54) and 'pain' (n=52). The three most prevalent difficulties in daily life were 'sitting' (n=63), 'wearing clothes' (n=56) and 'carrying out my daily activities' (n=51). 'Tiredness' (n=62), 'insecurity' (n=54) and 'feeling that my body has changed' (n=50) were the three most prevalent psychosocial symptoms/issues. The most distressing symptoms were 'sitting' (Mean 2.03, SD 0.88), 'open spot (e.g. opening of skin or suture)' (Mean 1.91, SD 0.93), and 'carrying out my daily activities' (Mean 1.86, SD 0.87), which were on average reported as 'quite a bit' distressing. Negative associations were found between psychosocial symptom experience and age. CONCLUSIONS WOMAN-PRO data showed a high symptom prevalence and distress, call for a comprehensive symptom assessment, and may allow identification of relevant areas in symptom management.
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THE INFLUENCE of combat sport practice on behaviour, attitude, personality and other factors was, and still remains, a research topic of great interest as well as conflicting points of view. Findings are as yet inconclusive since a direct or causal effect is difficult to establish and other factors external to the individual, such as the instructor’s coaching style, also need to be taken into consideration. Furthermore, the wide range of disciplines pertaining to the category combat sports differ from each other on a number of characteristics, such as the extent of physical contact or competition rules, and in fact, attempts have been made to distinguish between various sub-types (e.g. Trulson, 1986). A common distinction made is that between the traditional martial arts, which place emphasis on the art’s philosophy, its traditions and hierarchy (e.g. traditional karate, aikido) and the modern (or Western) combat sports (e.g. boxing, Mixed Martial Arts). An ongoing debate exists about the potential positive and/or negative influence of combat sport practice in comparison to other sport disciplines that do not include this element of fighting and direct aggression. On the one hand, combat sports have been presented by some researchers and sport practitioners as a means of promoting positive social and individual behavior, such as in Theeboom, De Knop and Wylleman’s (2008) evaluation of a martial arts Programme for socially disadvantaged youths in Belgium. Results revealed a positive effect of this project; however, it also highlighted the crucial role played by the instructors or leaders of such programmes. In another intervention using martial arts, Trulson (1986) reported a positive effect of a six month traditional martial art (Korean Tae Kwon Do) intervention with male juvenile delinquents including a reduction in aggressiveness and anxiety, thus confirming the positive influence of such an activity. Nevertheless, this effect was not observed in the other group participating in a modern Adaptation of this martial art led by the same instructor, where the philosophical aspect of this discipline was not emphasised. Moreover, an opposite effect was ascertained in this case where an increased tendency towards delinquency was reported. These results support the distinction between the various types of combat sports together with the way this sport is presented and taught by the instructor.
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BACKGROUND & Aims: Standardized instruments are needed to assess the activity of eosinophilic esophagitis (EoE), to provide endpoints for clinical trials and observational studies. We aimed to develop and validate a patient-reported outcome (PRO) instrument and score, based on items that could account for variations in patients' assessments of disease severity. We also evaluated relationships between patients' assessment of disease severity and EoE-associated endoscopic, histologic, and laboratory findings. METHODS We collected information from 186 patients with EoE in Switzerland and the US (69.4% male; median age, 43 years) via surveys (n = 135), focus groups (n = 27), and semi-structured interviews (n = 24). Items were generated for the instruments to assess biologic activity based on physician input. Linear regression was used to quantify the extent to which variations in patient-reported disease characteristics could account for variations in patients' assessment of EoE severity. The PRO instrument was prospectively used in 153 adult patients with EoE (72.5% male; median age, 38 years), and validated in an independent group of 120 patients with EoE (60.8% male; median age, 40.5 years). RESULTS Seven PRO factors that are used to assess characteristics of dysphagia, behavioral adaptations to living with dysphagia, and pain while swallowing accounted for 67% of the variation in patients' assessment of disease severity. Based on statistical consideration and patient input, a 7-day recall period was selected. Highly active EoE, based on endoscopic and histologic findings, was associated with an increase in patient-assessed disease severity. In the validation study, the mean difference between patient assessment of EoE severity and PRO score was 0.13 (on a scale from 0 to 10). CONCLUSIONS We developed and validated an EoE scoring system based on 7 PRO items that assesses symptoms over a 7-day recall period. Clinicaltrials.gov number: NCT00939263.
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Leptospirosis is a global zoonotic disease. Pathogenic Leptospira species, the causative agent of leptospirosis, colonize the renal tubules of chronically infected maintenance hosts such as dogs, rats and cattle. Maintenance hosts typically remain clinically asymptomatic and shed leptospires into the environment via urine. In contrast, accidental hosts such as humans can suffer severe acute forms of the disease. Infection results from direct contact with infected urine or indirectly, through contaminated water sources. In this study, a quantitative real-time PCR specific for lipL32 was designed to detect the urinary shedding of leptospires from dogs. The sensitivity and specificity of the assay was evaluated using both a panel of pathogenic Leptospira species and clinical microbial isolates, and samples of urine collected from experimentally infected rats and non-infected controls. The lower limit of detection was approximately 3 genome equivalents per reaction. The assay was applied to canine urine samples collected from local dog sanctuaries and the University Veterinary Hospital (UVH) at University College Dublin. Of 525 canine urine samples assayed, 37 were positive, indicating a prevalence of urinary shedding of leptospires of 7.05%. These results highlight the need to provide effective canine vaccination strategies and raise public health awareness.
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Simulating the spatio-temporal dynamics of inundation is key to understanding the role of wetlands under past and future climate change. Earlier modelling studies have mostly relied on fixed prescribed peatland maps and inundation time series of limited temporal coverage. Here, we describe and assess the the Dynamical Peatland Model Based on TOPMODEL (DYPTOP), which predicts the extent of inundation based on a computationally efficient TOPMODEL implementation. This approach rests on an empirical, grid-cell-specific relationship between the mean soil water balance and the flooded area. DYPTOP combines the simulated inundation extent and its temporal persistency with criteria for the ecosystem water balance and the modelled peatland-specific soil carbon balance to predict the global distribution of peatlands. We apply DYPTOP in combination with the LPX-Bern DGVM and benchmark the global-scale distribution, extent, and seasonality of inundation against satellite data. DYPTOP successfully predicts the spatial distribution and extent of wetlands and major boreal and tropical peatland complexes and reveals the governing limitations to peatland occurrence across the globe. Peatlands covering large boreal lowlands are reproduced only when accounting for a positive feedback induced by the enhanced mean soil water holding capacity in peatland-dominated regions. DYPTOP is designed to minimize input data requirements, optimizes computational efficiency and allows for a modular adoption in Earth system models.
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BACKGROUND Although the possibility of bleeding during anticoagulant treatment may limit patients from taking part in physical activity, the association between physical activity and anticoagulation-related bleeding is uncertain. OBJECTIVES To determine whether physical activity is associated with bleeding in elderly patients taking anticoagulants. PATIENTS/METHODS In a prospective multicenter cohort study of 988 patients aged ≥65 years receiving anticoagulants for venous thromboembolism, we assessed patients' self-reported physical activity level. The primary outcome was the time to a first major bleeding, defined as fatal bleeding, symptomatic bleeding in a critical site, or bleeding causing a fall in hemoglobin or leading to transfusions. The secondary outcome was the time to a first clinically-relevant non-major bleeding. We examined the association between physical activity level and time to a first bleeding using competing risk regression, accounting for death as a competing event. We adjusted for known bleeding risk factors and anticoagulation as a time-varying covariate. RESULTS During a mean follow-up of 22 months, patients with a low, moderate, and high physical activity level had an incidence of major bleeding of 11.6, 6.3, and 3.1 events per 100 patient-years, and an incidence of clinically relevant non-major bleeding of 14.0, 10.3, and 7.7 events per 100 patient-years, respectively. A high physical activity level was significantly associated with a lower risk of major bleeding (adjusted sub-hazard ratio 0.40, 95%-CI 0.22-0.72). There was no association between physical activity and non-major bleeding. CONCLUSIONS A high level of physical activity is associated with a decreased risk of major bleeding in elderly patients receiving anticoagulant therapy. This article is protected by copyright. All rights reserved.
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Antegrade nailing of proximal humeral fractures using a straight nail can damage the bony insertion of the supraspinatus tendon and may lead to varus failure of the construct. In order to establish the ideal anatomical landmarks for insertion of the nail and their clinical relevance we analysed CT scans of bilateral proximal humeri in 200 patients (mean age 45.1 years (sd 19.6; 18 to 97) without humeral fractures. The entry point of the nail was defined by the point of intersection of the anteroposterior and lateral vertical axes with the cortex of the humeral head. The critical point was defined as the intersection of the sagittal axis with the medial limit of the insertion of the supraspinatus tendon on the greater tuberosity. The region of interest, i.e. the biggest entry hole that would not encroach on the insertion of the supraspinatus tendon, was calculated setting a 3 mm minimal distance from the critical point. This identified that 38.5% of the humeral heads were categorised as 'critical types', due to morphology in which the predicted offset of the entry point would encroach on the insertion of the supraspinatus tendon that may damage the tendon and reduce the stability of fixation. We therefore emphasise the need for 'fastidious' pre-operative planning to minimise this risk.
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Recent studies have demonstrated that the improved prognosis derived from resection of gliomas largely depends on the extent and quality of the resection, making maximum but safe resection the ultimate goal. Simultaneously, technical innovations and refined neurosurgical methods have rapidly improved efficacy and safety. Because gliomas derive from intrinsic brain cells, they often cannot be visually distinguished from the surrounding brain tissue during surgery. In order to appreciate the full extent of their solid compartment, various technologies have recently been introduced. However, radical resection of infiltrative glioma puts neurological function at risk, with potential detrimental consequences for patients' survival and quality of life. The allocation of various neurological functions within the brain varies in each patient and may undergo additional changes in the presence of a tumour (brain plasticity), making intra-operative localisation of eloquent areas mandatory for preservation of essential brain functions. Combining methods that visually distinguish tumour tissue and detect tissues responsible for critical functions now enables resection of tumours in brain regions that were previously considered off-limits, and benefits patients by enabling a more radical resection, while simultaneously lowering the risk of neurological deficits. Here we review recent and expected developments in microsurgery for glioma and their respective benefits.
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BACKGROUND Flavobacterium psychrophilum is the agent of Bacterial Cold Water Disease and Rainbow Trout Fry Syndrome, two diseases leading to high mortality. Pathogen detection is mainly carried out using cultures and more rapid and sensitive methods are needed. RESULTS We describe a qPCR technique based on the single copy gene β' DNA-dependent RNA polymerase (rpoC). Its detection limit was 20 gene copies and the quantification limit 103 gene copies per reaction. Tests on spiked spleens with known concentrations of F. psychrophilum (106 to 101 cells per reaction) showed no cross-reactions between the spleen tissue and the primers and probe. Screening of water samples and spleens from symptomless and infected fishes indicated that the pathogen was already present before the outbreaks, but F. psychrophilum was only quantifiable in spleens from diseased fishes. CONCLUSIONS This qPCR can be used as a highly sensitive and specific method to detect F. psychrophilum in different sample types without the need for culturing. qPCR allows a reliable detection and quantification of F. psychrophilum in samples with low pathogen densities. Quantitative data on F. psychrophilum abundance could be useful to investigate risk factors linked to infections and also as early warning system prior to potential devastating outbreak.