White ascospore mutants in Ascobolus immersus: lack of the secondary spore wall, and allelism-testing

Ascospore pigmentation mutants have been very important in studies of gene conversion and crossing-over in such fungi as Neurospora, Sordaria and Ascobolus. Most such mutants are autonomous, with each haploid ascospore\u27s genotype controlling its phenotype. In the Pasadena strains of Ascobolus immersus, where wild-type (+) ascospores are red/brown, we have autonomous white (w) mutants at several different loci. The white spores are completely unpigmented in + x w crosses, even though the apothecia and hyphae are a mixture of + and w genotypes. The developing w ascospores are surrounded by the same ascal sap as the + spores, yet do not develop pigment even if in contact with a + spore. Possible explanations for the non-pigmentation of white ascospores are: (i) they are structurally the same as red/brown + spores but cannot make the pigment even if some precursors are present in the ascus; (ii) the mutant ascospores could make the pigment but lack some suitable structure for it to form on - a parallel would be white-eyed Drosophila of w,w;Cn,Cn;Bn,Bn genotype, which have no eye pigment because they lack the pigment-attachment protein from W, although they can make pterins and ommochrome pigments from Cn,Bn. In case (ii), the lack of a structural feature in white ascospores might change other properties, such as optimum germination conditions

Biobased polyester from soybean oil: Synthesis, characterization and degradation studies

Industrially used polymers derived from fossil fuels have a negative environmental impact when being disposed of. They could be efficiently replaced by natural polymers, which are potentially degradable and which can match or even surpass them in mechanical performance. In this work, a rigid thermosetting polymer is obtained by copolymerization of maleinated acrylated epoxidized soybean oil (MAESO) with styrene (St). MAESO is synthetized by epoxidation, acrylation and maleinization from industrial soybean oil (SO). Resin characterization is performed using FT-IR,1H NMR and SEC, while copolymer characterization includes a mechanical test, degradation test and SEM. The aim of this work is the replacement of unsaturated polyester (UP) and the optimization of the SO modification reaction in MAESO. The replacement of UP by 25, 50 and 100% of MAESO enables improvements in the mechanical properties. Additionally, it is assessed whether the replacement of UP by MAESO is enough to improve the degradation properties, and the effect of degradation on the mechanical properties is analyzed. MAESO-St copolymers improve the degradation process in relation to UP, and 240 days of in vitro degradation in the presence of Aspergillus niger and Alternaria alternata fungi causes cracks, surface damage and changes in the mechanical properties of the degraded copolymer.Fil: Bernard, Mariana Del Valle. Universidad Tecnológica Nacional. Facultad Regional San Francisco. Departamento de Ingeniería Electromecánica; ArgentinaFil: Nicolau, Veronica Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Strumia, Miriam Cristina. Universidad Tecnológica Nacional. Facultad Regional San Francisco. Departamento de Ingeniería Electromecánica; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Química Orgánica; Argentina. Universidad Nacional de Córdoba. Instituto de Investigación y Desarrollo en Ingeniería de Procesos y Química Aplicada. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación y Desarrollo en Ingeniería de Procesos y Química Aplicada; Argentin

Acteurs et agents, points de vue géographiques au sein des sciences sociales

En guise d’avant-propos introductif Dans son texte de présentation, Jean-Pierre Gaudin brasse de façon succincte mais très efficace la problématique de l’acteur. S’interroger sur ce que c’est qu’un acteur revient à ouvrir un éventail de questions qui sont au cœur de toute problématique scientifique dans les sciences sociales, et notamment à mettre le doigt sur l’arbitraire de toute une série d’oppositions qui jouissent néanmoins encore d’une fortune incontestée : individu contre société, subj..

Architecture of the AP2:clathrin coat on the membranes of clathrin-coated vesicles

AbstractClathrin-mediated endocytosis (CME) is crucial for modulating the protein composition of a cell’s plasma membrane. Clathrin forms a cage-like, polyhedral outer scaffold around a vesicle, to which cargo-selecting clathrin adaptors are attached. AP2 is the key adaptor in CME. Crystallography has shown AP2 to adopt a range of conformations. Here we used cryo-electron microscopy, tomography and subtomogram averaging to determine structures, interactions and arrangements of clathrin and AP2 at the key steps of coat assembly, from AP2 in solution to membrane-assembled clathrin-coated vesicles (CCVs). AP2 binds cargo and PtdIns(4,5)P2-containing membranes via multiple interfaces, undergoing conformational rearrangement from its cytosolic state. The binding mode of AP2 β2-appendage into the clathrin lattice in CCVs and buds implies how the adaptor structurally modulates coat curvature and coat disassembly.</jats:p

Lessons from end-of-life care among schizophrenia patients with cancer: a population- based cohort study from the French national hospital database Running title: End-of-life care among patients with schizophrenia and cancer

International audienceBackgroundPatients with schizophrenia represent a vulnerable, underserved, and undertreated population who have been neglected in health disparities work. Understanding of end-of-life care in patients with schizophrenia and cancer is poor. We aimed to establish whether end-of-life care delivered to patients with schizophrenia and cancer differed from that delivered to patients with cancer who do not have diagnosed mental illness.MethodsWe did a population-based cohort study of all patients older than 15 years who had a diagnosis of advanced cancer and who died in hospital in France between Jan 1, 2013, and Dec 31, 2016. We divided this population into cases (ie, patients with schizophrenia) and controls (ie, patients without a diagnosis of mental illness) and compared access to palliative care and indicators of high-intensity end-of-life care between groups. In addition to unmatched analyses, we also did matched analyses (matched in terms of age at death, sex, and site of primary cancer) between patients with schizophrenia and matched controls (1:4). Multivariable generalised linear models were done with adjustment for social deprivation, year of death, time from cancer diagnosis to death, metastases, comorbidity, and hospital type (ie, specialist cancer centre vs non-specialist centre).FindingsThe main analysis included 2481 patients with schizophrenia and 222 477 controls. The matched analyses included 2477 patients with schizophrenia and 9896 controls. Patients with schizophrenia were more likely to receive palliative care in the last 31 days of life (adjusted odds ratio 1·61 [95% CI 1·45–1·80]; p<0·0001) and less likely to receive high-intensity end-of-life care—such as chemotherapy and surgery—than were matched controls without a diagnosis of mental illness. Patients with schizophrenia were also more likely to die younger, had a shorter duration between cancer diagnosis and death, and were more likely to have thoracic cancers and comorbidities than were controls.InterpretationOur findings suggest the existence of disparities in health and health care between patients with schizophrenia and patients without a diagnosis of mental illness. These findings underscore the need for better understanding of health inequalities so that effective interventions can be developed for this vulnerable population

Efficacy and safety data based on historical or pre-existing conditions at baseline for patients with active rheumatoid arthritis who were treated with baricitinib

This study was funded by Eli Lilly and Company and Incyte Corporatio

Cassava yield loss in farmer fields was mainly caused by low soil fertility and suboptimal management practices in two provinces of the Democratic Republic of Congo

Article purchasedA better understanding of the factors that contribute to low cassava yields in farmers’ fields is required to guide the formulation of cassava intensification programs. Using a boundary line approach, we analysed the contribution of soil fertility, pest and disease infestation and farmers’ cultivation practices to the cassava yield gap in Kongo Central (KC) and Tshopo (TSH) provinces of the Democratic Republic of Congo. Data were obtained by monitoring 42 and 37 farmer-managed cassava fields during two cropping cycles in KC and one cropping cycle in TSH, respectively. Each field was visited three times over the cassava growing period for the observations. Logistic model was fitted against the observed maximum cassava root yields and used to calculate the achievable yield per field and for individual factor. At field level, the factor that led to the lowest achievable yield (Yup(i)1) was considered as the dominant yield constraint. Cassava yield loss per field was expressed as the increase in the maximal root yield observed per province (Yatt- attainable yield) compared to Yup(i)1. Yatt was 21 and 24 t ha−1 in TSH and KC, respectively. With the cassava varieties that farmers are growing in the study areas, pests and diseases played a sparse role in the yield losses. Cassava mosaic was the only visible disease we observed and it was the dominant yield constraint in 3% and 12% of the fields in KC and TSH, respectively. The frequent yield constraints were suboptimal field management and low soil fertility. Cultivation practices and soil parameters led to Yup(i)1 in 47% and 50% of the fields in KC, and in 47% and 41% of those in TSH, respectively. Individual soil parameters were the yield constraint in few fields, suggesting that large-scale programs in terms of lime application or recommendation of the blanket fertilisers would result in sparse efficacy. In KC, yield losses caused by low soil fertility averaged 6.2 t ha−1 and were higher than those caused by suboptimal field management (5.5 t ha−1); almost nil for cassava mosaic disease (CMD). In TSH, yield losses caused by low soil fertility (4.5 t ha−1) were lower than those caused by suboptimal field management (6.5 t ha−1) and CMD (6.1 t ha−1). Irrespective of the constraint type, yield loss per field was up to 48% and 64% of the Yatt in KC and TSH, respectively. Scenario analysis indicated that the yield losses would remain at about two third of these levels while the dominant constraint was only overcome. We concluded that integrated and site-specific management practices are needed to close the cassava yield gap and maximize the efficacy of cassava intensification programs

A motif within the N-terminal domain of TSP-1 specifically promotes the proangiogenic activity of endothelial colony-forming cells

Thrombospondin-1 (TSP-1) gives rise to fragments that have both pro- and anti-angiogenic effects in vitro and in vivo. the TSP-HepI peptide (2.3 kDa), located in the N-terminal domain of TSP-1, has proangiogenic effects on endothelial cells. We have previously shown that TSP-1 itself exhibits a dual effect on endothelial colony-forming cells (ECFC) by enhancing their adhesion through its TSP-HepI fragment while reducing their proliferation and differentiation into vascular tubes (tubulogenesis) in vitro. This effect is likely mediated through CD47 binding to the TSP-1 C-terminal domain. Here we investigated the effect of TSP-HepI peptide on the angiogenic properties of ECFC in vitro and in vivo. TSP-HepI peptide potentiated FGF-2-induced neovascularisation by enhancing ECFC chemotaxis and tubulogenesis in a Matrigel plug assay. ECFC exposure to 20 mu g/mL of TSP-HepI peptide for 18 h enhanced cell migration (p < 0.001 versus VEGF exposure), upregulated alpha 6-integrin expression, and enhanced their cell adhesion to activated endothelium under physiological shear stress conditions at levels comparable to those of SDF-1 alpha. the adhesion enhancement appeared to be mediated by the heparan sulfate proteoglycan (HSPG) syndecan-4, as ECFC adhesion was significantly reduced by a syndecan-4-neutralising antibody. ECFC migration and tubulogenesis were stimulated neither by a TSP-HepI peptide with a modified heparin-binding site (S/TSP-HepI) nor when the glycosaminoglycans (GAGS) moieties were removed from the ECFC surface by enzymatic treatment. Ex vivo TSP-HepI priming could potentially serve to enhance the effectiveness of therapeutic neovascularisation with ECFC. (C) 2012 Elsevier Inc. All rights reserved.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Groupe d'Etude et de Recherches sur l'Hemostase (GEHT)Region Ile-de-France (CORDDIM)Leducq TransAtlantic Network of ExcellenceUniv Estado Rio de Janeiro, Dept Biol Celular, Lab Biol Celula Endotelial & Angiogenese LabAngio, Inst Biol Roberto Alcantara Gomes, BR-20550011 Rio de Janeiro, RJ, BrazilINSERM, U765, Paris, FranceUniv Paris 05, Paris, FranceUniversidade Federal de São Paulo, Escola Paulista Med, Dept Biofis, São Paulo, BrazilUniv Fed Rio de Janeiro, Inst Ciencias Biomed, Rio de Janeiro, RJ, BrazilHop Europeen Georges Pompidou, AP HP, Dept Haematol, Paris, FranceINSERM, Paris Cardiovasc Res Ctr, U970, Paris, FranceUniversidade Federal de São Paulo, Escola Paulista Med, Dept Biofis, São Paulo, BrazilLeducq TransAtlantic Network of Excellence: 04CVD01-LENALeducq TransAtlantic Network of Excellence: 04CVD02 -LINATCNPq: E-26/110.780/2010CAPES: 629/09Web of Scienc

Clinical outcome of pneumococcal meningitis during the emergence of pencillin-resistant Streptococcus pneumoniae: an observational study

<p>Abstract</p> <p>Background</p> <p>Prior to the availability of generic third-generation cephalosporins, penicillins were widely used for treatment of pneumococcal meningitis in developing countries despite concerns about rising levels of penicillin resistance among pneumococcal isolates. We examined the impact of penicillin resistance on outcomes of pneumococcal meningitis over a ten year period in an infectious diseases hospital in Brazil.</p> <p>Methods</p> <p>Clinical presentation, antimicrobial therapy and outcomes were reviewed for 548 patients with culture-confirmed pneumococcal meningitis from December, 1995, to November, 2005. Pneumococcal isolates from meningitis patients were defined as penicillin-resistant if Minimum Inhibitory Concentrations for penicillin were greater than 0.06 μg/ml. Proportional hazards regression was used to identify risk factors for fatal outcomes.</p> <p>Results</p> <p>During the ten-year period, ceftriaxone replaced ampicillin as first-line therapy for suspected bacterial meningitis. In hospital case-fatality for pneumococcal meningitis was 37%. Of 548 pneumococcal isolates from meningitis cases, 92 (17%) were resistant to penicillin. After controlling for age and severity of disease at admission, penicillin resistance was associated with higher case-fatality (Hazard Ratio [HR], 1.62; 95% Confidence Interval [CI], 1.08-2.43). Penicillin-resistance remained associated with higher case-fatality when initial therapy included ceftriaxone (HR, 1.68; 95% CI 1.02-2.76).</p> <p>Conclusions</p> <p>Findings support the use of third generation cephalosporin antibiotics for treatment of suspected pneumococcal meningitis even at low prevalence of pneumococcal resistance to penicillins.</p