182 research outputs found

    Bacillus amyloliquefaciens GA1 as a source of potent antibiotics and other secondary metabolites for biocontrol of plant pathogens

    Get PDF
    Phytopathogenic fungi affecting crop and post-harvested vegetables are a amajor threat to food production and food storage. To face these drawbacks, producers have become increasingly dependent on agrochemicals. However, intensive use of these compounds has led to the emergence of pathogen resistance and severe negative environmental impacts. There are also a number of plant diseases for which chemical solutions are ineffective or non-existent as well as an increasing demand by consumers for pesticide-free food. Thus, biological control through the use of natural antagonistic microorganisms has emerged as a promising alternative to chemical pesticides for more rational and safe crop management. RESULTS: The genome of the plant-associated B. amyloliquefaciens GA1 was sample sequenced. Several gene clusters involved in the synthesis of biocontrol agents were detected. Four gene clusters were shown to direct the synthesis of the cyclic lipopeptides surfactin, iturin A and fengycin as well as the iron-siderophore bacillibactin. Beside these non-ribosomaly synthetised peptides, three additional gene clusters directing the synthesis of the antibacterial polyketides macrolactin, bacillaene and difficidin were identified. Mass spectrometry analysis of culture supernatants led to the identification of these secondary metabolites, hence demonstrating that the corresponding biosynthetic gene clusters are functional in strain GA1. In addition, genes encoding enzymes involved in synthesis and export of the dipeptide antibiotic bacilysin were highlighted. However, only its chlorinated derivative, chlorotetaine, could be detected in culture supernatants. On the contrary, genes involved in ribosome-dependent synthesis of bacteriocin and other antibiotic peptides were not detected as compared to the reference strain B. amyloliquefaciens FZB42. CONCLUSION: The production of all of these antibiotic compounds highlights B. amyloliquefaciens GA1 as a good candidate for the development of biocontrol agents

    Association between neighborhood physical characteristics and mental health among older adults in Spain

    Full text link
    The aim was to assess the impact of neighborhood physical environment on mental health among non-institutionalized older adults. A cross-sectional analysis was conducted over a representative sample of 5,071 people 65 years from the Spanish National Health Survey. The survey included nine items addressing the self-perceived degree of discomfort due to neighborhood physical problems. Participants were categorized into groups with “no problems”, “some problems” (somewhat discomfort on 1 4 items) and “many problems” (somewhat discomfort on 5 items or very much discomfort on 1 item). Mental health status was assessed using the General Health Questionnaire, consisting of 12 items assessing the severity of a psychological distress over the past few weeks. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated using logistic regressions. A dose-response association (p-trend<0.001) was found between living in neighborhoods with some (OR: 1.41; 95% CI: 1.14 1.75) or many problems (OR: 1.93; 95% CI: 1.55 2.42) affecting the physical environment with poor mental health of community dwelling older adults. Integrating and articulating health considerations into public policymaking regarding housing and the residential environment can have broad implications for healthy agin

    Cyclic lipopeptide‐producing Pseudomonas koreensis group strains dominate the cocoyam rhizosphere of a Pythium root rot suppressive soil contrasting with P. putida prominence in conducive soils

    Get PDF
    Pseudomonas isolates from tropical environments have been underexplored and may form an untapped reservoir of interesting secondary metabolites. In this study, we compared Pseudomonas and cyclic lipopeptide (CLP) diversity in the rhizosphere of a cocoyam root rot disease (CRRD) suppressive soil in Boteva, Cameroon with those from four conducive soils in Cameroon and Nigeria. Compared with other soils, Boteva andosols were characterized by high silt, organic matter, nitrogen and calcium. Besides, the cocoyam rhizosphere at Boteva was characterized by strains belonging mainly to the P . koreensis and P . putida (sub)groups, with representations in the P . fluorescens , P . chlororaphis , P . jessenii and P . asplenii (sub)groups. In contrast, P . putida isolates were prominent in conducive soils. Regarding CLP diversity, Boteva was characterized by strains producing 11 different CLP types with cocoyamide A producers, belonging to the P . koreensis group, being the most abundant. However, putisolvin III‐V producers were the most dominant in the rhizosphere of conducive soils in both Cameroon and Nigeria. Furthermore, we elucidated the chemical structure of putisolvin derivatives—putisolvin III‐V, and described its biosynthetic gene cluster. We show that high Pseudomonas and metabolic diversity may be driven by microbial competition, which likely contributes to soil suppressiveness to CRRD

    Integrating the STOP-BANG Score and Clinical Data to Predict Cardiovascular Events After Infarction A Machine Learning Study

    Get PDF
    BACKGROUND: OSA conveys worse clinical outcomes in patients with coronary artery disease. The STOP-BANG score is a simple tool that evaluates the risk of OSA and can be added to the large number of clinical variables and scores that are obtained during the management of patients with myocardial infarction (MI). Currently, machine learning (ML) is able to select and integrate numerous variables to optimize prediction tasks. RESEARCH QUESTION: Can the integration of STOP-BANG score with clinical data and scores through ML better identify patients who experienced an in-hospital cardiovascular event after acute MI? STUDY DESIGN AND METHOD: This is a prospective observational cohort study of 124 patients with acute MI of whom the STOP-BANG score classified 34 as low (27.4%), 30 as intermediate (24.2%), and 60 as high (48.4%) OSA-risk patients who were followed during hospitalization. ML implemented feature selection and integration across 47 variables (including STOP-BANG score, Killip class, GRACE score, and left ventricular ejection fraction) to identify those patients who experienced an in-hospital cardiovascular event (ie, death, ventricular arrhythmias, atrial fibrillation, recurrent angina, reinfarction, stroke, worsening heart failure, or cardiogenic shock) after definitive MI treatment. Receiver operating characteristic curves were used to compare ML performance against STOP-BANG score, Killip class, GRACE score, and left ventricular ejection fraction, independently. RESULTS: There were an increasing proportion of cardiovascular events across the low, intermediate, and high OSA risk groups (P = .005). ML selected 7 accessible variables (ie, Killip class, leukocytes, GRACE score, c reactive protein, oxygen saturation, STOP-BANG score, and N-terminal prohormone of B-type natriuretic peptide); their integration outperformed all comparators (area under the curve, 0.83 [95% CI, 0.74-0.90]; P <.01). INTERPRETATION: The integration of the STOP-BANG score into clinical evaluation (considering Killip class, GRACE score, and simple laboratory values) of subjects who were admitted for an acute MI because of ML can significantly optimize the identification of patients who will experience an in-hospital cardiovascular event

    Evolution after Anti-TNF Discontinuation in Patients with Inflammatory Bowel Disease: A Multicenter Long-Term Follow-Up Study

    Get PDF
    OBJECTIVES:The aims of this study were to assess the risk of relapse after discontinuation of anti-tumor necrosis factor (anti-TNF) drugs in patients with inflammatory bowel disease (IBD), to identify the factors associated with relapse, and to evaluate the overcome after retreatment with the same anti-TNF in those who relapsed.METHODS:This was a retrospective, observational, multicenter study. IBD patients who had been treated with anti-TNFs and in whom these drugs were discontinued after clinical remission was achieved were included.RESULTS:A total of 1, 055 patients were included. The incidence rate of relapse was 19% and 17% per patient-year in Crohn''s disease and ulcerative colitis patients, respectively. In both Crohn''s disease and ulcerative colitis patients in deep remission, the incidence rate of relapse was 19% per patient-year. The treatment with adalimumab vs. infliximab (hazard ratio (HR)=1.29; 95% confidence interval (CI)=1.01-1.66), elective discontinuation of anti-TNFs (HR=1.90; 95% CI=1.07-3.37) or discontinuation because of adverse events (HR=2.33; 95% CI=1.27-2.02) vs. a top-down strategy, colonic localization (HR=1.51; 95% CI=1.13-2.02) vs. ileal, and stricturing behavior (HR=1.5; 95% CI=1.09-2.05) vs. inflammatory were associated with a higher risk of relapse in Crohn''s disease patients, whereas treatment with immunomodulators after discontinuation (HR=0.67; 95% CI=0.51-0.87) and age (HR=0.98; 95% CI=0.97-0.99) were protective factors. None of the factors were predictive in ulcerative colitis patients. Retreatment of relapse with the same anti-TNF was effective (80% responded) and safe.CONCLUSIONS:The incidence rate of inflammatory bowel disease relapse after anti-TNF discontinuation is relevant. Some predictive factors of relapse after anti-TNF withdrawal have been identified. Retreatment with the same anti-TNF drug was effective and safe

    Monoclonal Antibody and Fusion Protein Biosimilars Across Therapeutic Areas: A Systematic Review of Published Evidence

    Get PDF

    Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1.

    Get PDF
    In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field

    Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)

    Get PDF
    • 

    corecore