7,125 research outputs found
Deciphering effector function in the Magnaporthe oryzae rice interaction
Effectors are central to virulence in all pathogenic organisms and to their adaptation to specific hosts. However, the role and molecular function of fungal effector proteins is largely unknown. A better understanding of fungal effectors is necessary for a deeper understanding of fungal pathogenicity and for new perspectives in the development of durably resistant crops. Therefore, we perform systematic and targeted analysis of effectors of the causal agent of blast disease, the ascomycete fungus Magnaporthe oryzae, which is the most important rice pathogen and a model for the investigation of the molecular basis of fungal pathogenicity. Genome wide expression analysis allowed us the identification of ~100 effector candidates, secreted specifically during infection. Results from the functional analysis of promising candidates will be presented. Investigation of their localization during infection by life cell imaging studies and in vitro translocation assays indicate their translocation into host cells by unknown mechanisms. In addition, two hybrid screens and over expression studies in rice are beginning to shed light on targeted host proteins and host processes. (Texte intégral
Mean first passage time analysis reveals rate-limiting steps, parallel pathways and dead ends in a simple model of protein folding
We have analyzed dynamics on the complex free energy landscape of protein
folding in the FOLD-X model, by calculating for each state of the system the
mean first passage time to the folded state. The resulting kinetic map of the
folding process shows that it proceeds in jumps between well-defined, local
free energy minima. Closer analysis of the different local minima allows us to
reveal secondary, parallel pathways as well as dead ends.Comment: 7 page
Frailty Index and incident mortality, hospitalization and institutionalization in Alzheimer's disease: data from the ICTUS study.
BACKGROUND:
The identification of an objective evaluation of frailty capable of predicting adverse outcomes in Alzheimer's disease is increasingly discussed. The purpose of this study was to investigate whether the Frailty Index (FI) predicts hospitalization, institutionalization, and mortality in Alzheimer's disease patients.
METHODS:
A prospective multicenter cohort study (follow-up = 2 years) that included 1,191 participants with Alzheimer's disease was carried out. The outcomes of interest were incident hospitalization, institutionalization, and mortality. The FI was calculated as the ratio of actual to thirty potential deficits, that is, deficits presented by the participant divided by 30. Severity of dementia was assessed using the Clinical Dementia Rating score. Cox proportional hazard models were performed.
RESULTS:
Mean age of the study sample was 76.2 (SD = 7.6) years. A quadratic relationship of the FI with age was reported at baseline (R 2 = .045, p < .001). The FI showed a statistically significant association with mortality (age- and gender-adjusted hazard ratio [HR] = 1.019, 95% confidence interval [CI] = 1.002-1.037, p = .031) and hospitalization (age- and gender-adjusted HR = 1.017, 95% CI = 1.006-1.029, p = .004) and a borderline significance with institutionalization. When the Clinical Dementia Rating score was simultaneously included in the age- and gender-adjusted models, the FI confirmed its predictive capacity for hospitalization (HR = 1.019, 95% CI = 1.006-1.032, p = .004), whereas the Clinical Dementia Rating score was the strongest predictor for mortality (HR = 1.922, 95% CI = 1.256-2.941, p = .003) and institutionalization (HR = 1.955, 95%CI = 1.427-2.679, p < .001).
CONCLUSIONS:
The FI is a robust predictor of adverse outcomes even after the stage of the underlying dementia is considered. Future work should evaluate the clinical implementation of the FI in the assessment of demented individuals in order to improve the personalization of care
Optimal control strategies for tuberculosis treatment: a case study in Angola
We apply optimal control theory to a tuberculosis model given by a system of
ordinary differential equations. Optimal control strategies are proposed to
minimize the cost of interventions. Numerical simulations are given using data
from Angola.Comment: This is a preprint of a paper whose final and definite form will
appear in the international journal Numerical Algebra, Control and
Optimization (NACO). Paper accepted for publication 15-March-201
Modesty, liberty, equality: Negotiations of gendered principles of piety among Muslim women who cover
This article draws on a qualitative research study with Muslim women who cover to investigate how they represent the Islamic virtue of modesty. The article details findings that Muslim women elaborate modesty as an autonomous labour of ethical self-regulation and a relational virtue that is concerned with devotion to family and the de-sexualisation of day-to-day social interactions. It argues from analysis of representational content and dynamics that these accounts of modesty involve processes of affirming as well as resisting the liberal norms of equality, sexuality and agency that define Muslim veiling in the eyes of others
Sarcopenia and cognitive impairment in elderly women: results from the EPIDOS cohort
BACKGROUND: common pathophysiological pathways are shared between age-related body composition changes and cognitive impairment.
OBJECTIVE: evaluate whether current operative sarcopenia definitions are associated with cognition in community-dwelling older women.
DESIGN: cross-sectional analyses.
SUBJECTS: a total of 3,025 women aged 75 years and older.
MEASUREMENTS: body composition (assessed by dual energy X-ray absorptiometry) and cognition (measured by short portable mental status questionnaire) were obtained in all participants. Multivariate logistic regression models assessed the association of six operative definitions of sarcopenia with cognitive impairment. Gait speed (GS, measured over a 6-meter track at usual pace) and handgrip strength (HG, measured by a hand-held dynamometer) were considered additional factors of interest.
RESULTS: a total of 492 (16.3%) women were cognitively impaired. The prevalence of sarcopenia ranged from 3.3 to 18.8%. No sarcopenia definition was associated with cognitive impairment after controlling for potential confounders. To proof consistency, the analyses were performed using GS and HG, two well-established predictors of cognitive impairment. Low GS [odds ratio (OR) 2.42, 95% confidence interval (CI) 1.72-3.40] and low HG (OR: 1.81, 95% CI: 1.33-2.46) were associated with cognitive impairment.
CONCLUSION: no significant association was evidenced between different operative sarcopenia definitions and cognitive impairment. The study suggests that the association between physical performance and cognitive impairment in not mediated by sarcopenia
Measurements of the reaction of antiproton annihilation at rest at three hydrogen target densities
The proton-antiproton annihilation at rest into the final state
was measured for three different target densities: liquid hydrogen, gaseous
hydrogen at NTP and at a low pressure of 5 mbar. The yield of this reaction in
the liquid hydrogen target is smaller than in the low-pressure gas target. The
branching ratios of the channel were calculated on the basis of
simultaneous analysis of the three data samples. The branching ratio for
annihilation into from the protonium state turns out to be
about ten times smaller as compared to the one from the state.Comment: 10 pages, 3 Postscript figures. Accepted by Physics Letters
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