154 research outputs found

    The Genetic Architecture of Adaptation to Leaf and Root Bacterial Microbiota in Arabidopsis thaliana

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    Understanding the role of the host genome in modulating microbiota variation is a need to shed light on the holobiont theory and overcome the current limits on the description of host-microbiota interactions at the genomic and molecular levels. However, the host genetic architecture structuring microbiota is only partly described in plants. In addition, most association genetic studies on microbiota are often carried out outside the native habitats where the host evolves and the identification of signatures of local adaptation on the candidate genes has been overlooked. To fill these gaps and dissect the genetic architecture driving adaptive plant-microbiota interactions, we adopted a genome-environment association (GEA) analysis on 141 whole-genome sequenced natural populations of Arabidopsis thaliana characterized in situ for their leaf and root bacterial communities in fall and spring, and a large range of nonmicrobial ecological factors (i.e., climate, soil, and plant communities). A much higher fraction of among-population microbiota variance was explained by the host genetics than by nonmicrobial ecological factors. Importantly, the relative importance of host genetics and nonmicrobial ecological factors in explaining the presence of particular operational taxonomic units (OTUs) differs between bacterial families and genera. In addition, the polygenic architecture of adaptation to bacterial communities was highly flexible between plant compartments and seasons. Relatedly, signatures of local adaptation were stronger on quantitative trait loci (QTLs) of the root microbiota in spring. Finally, plant immunity appears as a major source of adaptive genetic variation structuring bacterial assemblages in A. thaliana

    Phosphate binding by a novel Zn(II) complex featuring a trans-1,2-diaminocyclohexane ligand. Effective anion recognition in water

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    Excellent affinities and selectivities toward triphosphates are achieved through an adaptive ditopic receptor featuring a metal ion and a macrocyclic polyammonium cation binding sites, concertedly bridging phosphate anions

    Signaling through Ras is essential for ret oncogene-induced cell differentiation in PC12 cells.

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    Specific germline mutations of the receptor tyrosine kinase, Ret, predispose to multiple endocrine neoplasia types 2A and 2B and familial medullary thyroid carcinoma. The mechanisms by which different Ret isoforms (Ret-2A and Ret-2B) cause distinct neoplastic diseases remain largely unknown. On the other hand, forced expression of these mutated versions of Ret induces the rat pheochromocytoma cell line, PC12, to differentiate. Here we used an inducible vector encoding a dominant-negative Ras (Ras p21(N17)) to investigate the contributions of the Ras pathway to the phenotype induced in PC12 cells by the expression of either Ret-2A or Ret-2B mutants. We show that the Ret-induced molecular and morphological changes are both mediated by Ras-dependent pathways. However, even though inhibition of Ras activity was sufficient to revert Ret-induced differentiation, the kinetics of morphological reversion of the Ret-2B- was more rapid than the Ret-2A- transfected cells. Further, we show that in Ret-transfected cells the suc1- associated neurotrophic factor-induced tyrosine phosphorylation target, SNT, is chronically phosphorylated in tyrosine residues, and associates with the Sos substrate. These results indicate the activation of the Ras cascade as an essential pathway triggered by the chronic active Ret mutants in PC12 cells. Moreover, our data indicate SNT as a substrate for both Ret mutants, which might mediate the activation of this cascade

    O055. Headache and psychopathological aspects in Gilles de la Tourette Sindrome:a comparison between paediatric and adult patients

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    Only few studies have analyzed the occurrence of headache in patients with Gilles de la Tourette syndrome (GTS) [1–3]. The aim of this study was to compare the prevalence and characteristics of headache in paediatric and adult patients with GTS and the relationship of headache with tic severity, psychiatric comorbidities and quality of life

    Adiponectin, diabetes and ischemic heart failure: a challenging relationship

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    Abstract Background Several peptides, named adipokines, are produced by the adipose tissue. Among those, adiponectin (AD) is the most abundant. AD promotes peripheral insulin sensitivity, inhibits liver gluconeogenesis and displays anti-atherogenic and anti-inflammatory properties. Lower levels of AD are related to a higher risk of myocardial infarction and a worse prognosis in patients with coronary artery disease. However, despite a favorable clinical profile, AD increases in relation to worsening heart failure (HF); in this context, higher adiponectinemia is reliably related to poor prognosis. There is still little knowledge about how certain metabolic conditions, such as diabetes mellitus, modulate the relationship between AD and HF. We evaluated the level of adiponectin in patients with ischemic HF, with and without type 2 diabetes, to elucidate whether the metabolic syndrome was able to influence the relationship between AD and HF. Results We demonstrated that AD rises in patients with advanced HF, but to a lesser extent in diabetics than in non-diabetics. Diabetic patients with reduced systolic performance orchestrated a slower rise of AD which began only in face of overt HF. The different behavior of AD in the presence of diabetes was not entirely explained by differences in body mass index. In addition, NT-proBNP, the second strongest predictor of AD, did not differ significantly between diabetic and non-diabetic patients. These data indicate that some other mechanisms are involved in the regulation of AD in patients with type 2 diabetes and coronary artery disease. Conclusions AD rises across chronic heart failure stages but this phenomenon is less evident in type 2 diabetic patients. In the presence of diabetes, the progressive increase of AD in relation to the severity of LV dysfunction is hampered and becomes evident only in overt HF.</p

    Prevalence and trends of markers of hepatitis B virus, hepatitis C virus and human Immunodeficiency virus in Argentine blood donors

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    BACKGROUND: Transfusion-transmitted infections are a major problem associated with blood transfusion. The aim of this study was to determine prevalence and trends of HBV, HCV and HIV in blood donors in Argentina. METHODS: A retrospective study was carried out in blood donors of 27 transfusion centers covering the whole country over a period of eight years (2004-2011). Serologic screening assays for HBsAg, anti-HBc, anti-HCV, and anti-HIV were performed in all centers and nucleic acid amplification testing (NAT) was performed in 2 out of the 27 centers. RESULTS: The 2,595,852 samples tested nationwide from 2004 to 2011 showed that the prevalence of HBsAg decreased from 0.336% to 0.198% (p < 0.0001), that of anti-HBc from 2.391% to 2.007% (p < 0.0001), that of anti-HCV from 0.721% to 0.460%, (p < 0.0001) and that of anti-HIV from 0.208% to 0.200 (p = 0.075). The prevalence of HBV, HCV and HIV was unevenly distributed among the different regions of the country. Two out of 74,838 screening- negative samples were positive in NAT assays (1 HIV-RNA and 1 HCV-RNA); moreover, HBV-DNA, HCV-RNA and HIV-RNA were detected in 60.29, 24.54 and 66.67% of screening-positive samples of the corresponding assays. As regards donors age, positive HBV-DNA and HCV-RNA donors were significantly older than healthy donors (46.6, 50.5 and 39.5 y respectively, p < 0.001). CONCLUSIONS: Argentina has a low prevalence of HBsAg, anti-HCV and anti-HIV in blood donors, with a decreasing trend for HBsAg, anti-HBc and anti-HCV but not for anti-HIV over the last 8 years. The uneven distribution of transfusion-transmitted infections prevalence among the different regions of the country highlights the need to implement regional awareness campaigns and prevention. The discrepancy between samples testing positive for screening assays and negative for NAT assays highlights the problem of blood donors who test repeatedly reactive in screening assays but are not confirmed as positive upon further testing. The uneven distribution of age between healthy donors and NAT-positive donors could be related to changes in risks of these pathogens in the general population and might be attributed to a longer exposure to transmission risk factors in elderly people.Fil: Flichman, Diego Martin. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cåtedra de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Blejer, Jorgelina L.. Fundación Hemocentro; ArgentinaFil: Livellara, Beatriz I.. Hospital Italiano; ArgentinaFil: Ré, Viviana Elizabeth. Universidad Nacional de Cordoba. Facultad de Medicina. Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bartoli, Sonia. Centro regional de Hemoterapia Jujuy; ArgentinaFil: Bustos, Juan A.. Banco de sangre San Jorge; ArgentinaFil: Ansola, Claudia P.. Provincia de Mendoza. Servicio de Hemoterapia; ArgentinaFil: Hidalgo, Susana. Hospital Dr. Enrique Vera Barros; ArgentinaFil: Cerda, Martín E.. Hospital Dr. Lucio Molas; ArgentinaFil: Levin, Alicia E.. Provincia de Mendoza. Servicio de Hemoterapia; ArgentinaFil: Huenul, Adriana. Hospital Artémides Zatti; ArgentinaFil: Riboldi, Victoria. Hospital Regional Río Gallegos; ArgentinaFil: Treviño, Elena M. C.. Universidad Nacional de Córdoba; ArgentinaFil: Salamone, Horacio J.. Fundación Favaloro; ArgentinaFil: Nuñez, Felix A.. Hospital Italiano; ArgentinaFil: Fernåndez, Robert J.. Fundación Hemocentro; ArgentinaFil: Reybaud, Juan F.. Fundación Favaloro; ArgentinaFil: Campos, Rodolfo Hector. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cåtedra de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Epicardial adipose tissue and insulin resistance in patients with coronary artery disease with or without left ventricular dysfunction

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    Background. Epicardial adipose tissue (EAT) is a visceral fat that fulfills two important functions: lipid-storage and secretion of adipokines with pro-inflammatory and pro-atherogenic properties. It has been suggested that EAT may affect the pathogenesis of atherosclerosis and the clinical course of coronary artery disease (CAD). In patients with obesity, diabetes and metabolic syndrome, the epicardial adipose tissue is enlarged. Little is known about the role of EAT in left ventricular dysfunction. Aim of this study was to evaluate the ability of insulin resistance to predict EAT thickness in patients with significant CAD and systolic dysfunction. Methods. We enrolled 114 subjects diagnosed with CAD by angiography. The majority underwent revascularization after an acute coronary syndrome. Patients were considered affected by significant left ventricular dysfunction when EF wa
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