Mostrando recursos 1 - 20 de 342.975

  1. 1Universidade Federal do Rio Grande do Sul (UFRGS), Faculdade de Medicina,

    Programa Pós-graduação; Ciências Médicas; Rua Ramiro Barcelos; Ricardo De Souza Kuchenbecker; Afonso Luis Barth
    Evaluation of respiratory syncytial virus group A and B genotypes among nosocomial and community-acquired pediatric infections in southern Brazil Fernanda de-Paris1,3*, Caroline Beck2, Luciana de Souza Nunes1, Alice Beatriz Mombach Pinheiro Machado3, study showed that the BA4 genotype remains in circulation. Deciphering worldwide RSV genetic variability will aid vaccine design and development. de-Paris et al. Virology Journal 2014, 11:36

  2. Patterns of gene flow define species of thermophilic Archaea. PLoS Biol

    Hinsby Cadillo-quiroz; Xavier Didelot; Nicole L. Held; Alfa Herrera; Aaron Darling; Michael L. Reno; David J. Krause; Rachel J. Whitaker
    Despite a growing appreciation of their vast diversity in nature, mechanisms of speciation are poorly understood in Bacteria and Archaea. Here we use high-throughput genome sequencing to identify ongoing speciation in the thermoacidophilic Archaeon Sulfolobus islandicus. Patterns of homologous gene flow among genomes of 12 strains from a single hot spring in Kamchatka, Russia, demonstrate higher levels of gene flow within than between two persistent, coexisting groups, demonstrating that these microorganisms fit the biological species concept. Furthermore, rates of gene flow between two species are decreasing over time in a manner consistent with incipient speciation. Unlike other microorganisms investigated, we...

  3. Jost’s D.

    Robert Harniman; Thomas J. S. Merritt; Lauren J. Chapman; Mery L. Martinez; Mery L. Martinez
    Population level response to hypoxia has become an issue of global significance because of increased frequency and intensity of hypoxic events worldwide, and the potential for global warming to exacerbate hypoxic stress. In this study, we sequenced two nuclear intronic regions and a single mitochondrial region across seven populations of the African cyprinid, Barbus neumayeri from two river drainages in Uganda: the Rwembaita Swamp-Njuguta River System and the Dura River. We then examined two indices of population structure, GST and Jost’s D, to detect links between oxygen availability and genetic variation and to determine if population genetic structure was associated...

  4. RESEARCH ARTICLE Cuticular Hydrocarbons of Orchid Bees Males: Interspecific and Chemotaxonomy

    Aline Borba Dos Santos; Fábio Santos Do Nascimento
    Recent studies have investigated the composition of compounds that cover the cuticle in social insects, but few studies have focused on solitary bees. Cuticular hydrocarbons may provide a tool for chemotaxonomy, and perhaps they can be used as a complement to mor-phology and genetic characters in phylogenetic studies. Orchid bees (Tribe Euglossini) are a highly diverse group of Neotropical bees with more than 200 species. Here, the cuticular hydrocarbons of 17 species were identified and statistical analysis revealed 108 com-pounds, which allowed for the taxonomic classification according to the genera. The most significant compounds discriminating the four genera were (Z)-9-pentacosene,...

  5. Review Article Possible Role of Human Herpesvirus 6 as a Trigger of Autoimmune Disease

    Francesco Broccolo; Lisa Fusetti; Luca Ceccherini-nelli
    Copyright © 2013 Francesco Broccolo et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Human herpesvirus 6 (HHV-6) infection is common and has a worldwide distribution. Recently, HHV-6A and HHV-6B have been reclassified into two distinct species based on different biological features (genetic, antigenic, and cell tropism) and disease associations. A role for HHV-6A/B has been proposed in several autoimmune disorders (AD), including multiple sclerosis (MS), autoimmune connective tissue diseases, and Hashimoto’s thyroiditis. The focus of this...

  6. Gamma-Tubulin Is Required for Bipolar Spindle Assembly and for Proper Kinetochore Microtubule Attachments during Prometaphase I in Drosophila

    Stacie E. Hughes; J. Scott Beeler; Angela Seat; Brian D. Slaughter; Jay R. Unruh; Heinrich J. G. Matthies; R. Scott Hawley
    In many animal species the meiosis I spindle in oocytes is anastral and lacks centrosomes. Previous studies of Drosophila oocytes failed to detect the native form of the germline-specific c-tubulin (cTub37C) in meiosis I spindles, and genetic studies have yielded conflicting data regarding the role of cTub37C in the formation of bipolar spindles at meiosis I. Our examination of living and fixed oocytes carrying either a null allele or strong missense mutation in the ctub37C gene demonstrates a role for cTub37C in the positioning of the oocyte nucleus during late prophase, as well as in the formation and maintenance of...

  7. High Diversity of Cryptosporidium Subgenotypes Identified in Malaysian HIV/AIDS Individuals Targeting

    Gp Gene; Asma Iqbal; Yvonne A. L. Lim; Johari Surin; Benedict L. H. Sim
    Background: Currently, there is a lack of vital information in the genetic makeup of Cryptosporidium especially in developing countries. The present study aimed at determining the genotypes and subgenotypes of Cryptosporidium in hospitalized Malaysian human immunodeficiency virus (HIV) positive patients. Methodology/Principal Findings: In this study, 346 faecal samples collected from Malaysian HIV positive patients were genetically analysed via PCR targeting the 60 kDa glycoprotein (gp60) gene. Eighteen (5.2 % of 346) isolates were determined as Cryptosporidium positive with 72.2 % (of 18) identified as Cryptosporidium parvum whilst 27.7 % as Cryptosporidium hominis. Further gp60 analysis revealed C. parvum belonging to...

  8. Case Report Dysphagia and Neck Swelling in a Case of Undiagnosed Lhermitte-Duclos Disease and Cowden Syndrome

    Zishuo Ian Hu; Lev Bangiyev; Roberta J. Seidman; Jules A. Cohen
    which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. We report a case of a 37-year-old woman presenting with dysphagia and thyroid masses who was subsequently diagnosed with Lhermitte-Duclos disease (LDD) based onMRI scan and histopathology. Additional imaging subsequently revealed the presence of thyroid nodules and bilateral breast cancers. Genetic testing later confirmed the diagnosis of Cowden syndrome.This case illustrates the importance of the overlap between LDD, Cowden syndrome, thyroid disease, and breast cancer. 1.

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    Groupe Hospitalier Pitié; Uf Cardiogénétique Et; Service De Biochimie; Bozorgmehr B. Md
    Objective Ullrich congenital muscular dystrophy (UCMD) corresponds to the severe end of the clinical spectrum of neuromuscular disorders caused by mutations in the genes encoding collagen VI (COL VI). We studied four unrelated families with six affected children that had typical UCMD with dominant and recessive inheritance. Materials & Methods Four unrelated Iranian families with six affected children with typical UCMD were analyzed for COLVI secretion in skin fibroblast culture and the secretion of COLVI in skin fibroblast culture using quantitative RT–PCR (Q-RT-PCR), and mutation identification was performed by sequencing of complementary DNA. Results COL VI secretion was altered in...

  10. Evolution in a Changing Environment

    Andrea Baronchelli; Nick Chater; Morten H. Christiansen; Romualdo Pastor-satorras
    We propose a simple model for genetic adaptation to a changing environment, describing a fitness landscape characterized by two maxima. One is associated with ‘‘specialist’ ’ individuals that are adapted to the environment; this maximum moves over time as the environment changes. The other maximum is static, and represents ‘‘generalist’ ’ individuals not affected by environmental changes. The rest of the landscape is occupied by ‘‘maladapted’ ’ individuals. Our analysis considers the evolution of these three subpopulations. Our main result is that, in presence of a sufficiently stable environmental feature, as in the case of an unchanging aspect of a...

  11. genetic

    Roberto Pacelli; Manuel Conson; Laura Cella; Raffaele Liuzzi; Giancarlo Troncone; Vincenzo Iorio; Raffaele Solla; Antonio Farella; Stefania Scala; Clorindo Pagliarulo; Marco Salvatore
    Radiation therapy following surgery for localized breast cancer: outcome

  12. ACUTE LYMPHOCYTIC LEUKEMIA (F RAVANDI, SECTION EDITOR) Cytogenetic and Molecular Predictors of Outcome in Acute Lymphocytic Leukemia: Recent Developments

    Ilaria Iacobucci; Cristina Papayannidis; Annalisa Lonetti; Anna Ferrari; Michele Baccarani; Giovanni Martinelli
    # The Author(s) 2012. This article is published with open access at Abstract During the last decade a tremendous technologic progress based on genome-wide profiling of genetic aberra-tions, structural DNA alterations, and sequence variations has allowed a better understanding of the molecular basis of pediatric and adult B/T- acute lymphoblastic leukemia (ALL), contributing to a better recognition of the biological heterogeneity of ALL and to a more precise definition of risk factors. Importantly, these advances identified novel potential targets for therapeutic intervention. This review will be focused on the cytogenetic/molecular advances in pediatric and adult ALL based on recently...

  13. Finding Evidence for Local Transmission of Contagious Disease in Molecular Epidemiological Datasets

    Rolf J. F. Ypma; Tjibbe Donker; W. Marijn Van Ballegooijen; Jacco Wallinga
    Surveillance systems of contagious diseases record information on cases to monitor incidence of disease and to evaluate effectiveness of interventions. These systems focus on a well-defined population; a key question is whether observed cases are infected through local transmission within the population or whether cases are the result of importation of infection into the population. Local spread of infection calls for different intervention measures than importation of infection. Besides standardized information on time of symptom onset and location of cases, pathogen genotyping or sequencing offers essential information to address this question. Here we introduce a method that takes full advantage...

  14. Original article RADB: a database of rheumatoid arthritis-related polymorphisms

    Ruijie Zhang; Meiwei Luan; Zhenwei Shang; Lian Duan; Guoping Tang; Miao Shi; Wenhua Lv; Hongjie Zhu; Jin Li; Hongchao Lv; Mingming Zhang; Guiyou Liu; He Chen; Yongshuai Jiang
    Rheumatoid arthritis (RA) is an autoimmune disease that has a complex genetic basis. Therefore, it is important to explore the genetic background of RA. The extensive recent application of polymorphic genetic markers, especially single nucleotide polymorph-isms, has presented us with a large quantity of genetic data. In this study, we developed the Database of Rheumatoid Arthritis-related Polymorphisms (RADB), to integrate all the RA-related genetic polymorphisms and provide a useful resource for researchers. We manually extracted the RA-related polymorphisms from 686 published reports, including RA susceptibility loci, polymorphisms associated with particular clinical features of RA, polymorphisms associated with drug response in...

  15. Molecular Comparisons of Full Length Metapneumovirus (MPV) Genomes, Including Newly Determined French AMPV-C and –D Isolates, Further Supports Possible Subclassification within the MPV Genus

    Paul A. Brown; Evelyne Lemaitre; Olivier Guionie; Didier Toquin; Nicolas Eterradossi
    Four avian metapneumovirus (AMPV) subgroups (A–D) have been reported previously based on genetic and antigenic differences. However, until now full length sequences of the only known isolates of European subgroup C and subgroup D viruses (duck and turkey origin, respectively) have been unavailable. These full length sequences were determined and compared with other full length AMPV and human metapneumoviruses (HMPV) sequences reported previously, using phylogenetics, comparisons of nucleic and amino acid sequences and study of codon usage bias. Results confirmed that subgroup C viruses were more closely related to HMPV than they were to the other AMPV subgroups in the...

  16. Genetic Determinants for Body Iron Store and Type 2 Diabetes Risk in US Men and Women

    Meian He; Tsegaselassie Workalemahu; Joann E. Manson; Frank B. Hu; Lu Qi
    Background: High body iron store has been associated with an increased risk of type 2 diabetes (T2D); it remains unknown whether the genetic variants related to body iron status affect T2D risk. We aimed at comprehensively investigating the associations between the genetic variants related to body iron status and the T2D risk. Methodology/Principal Findings: Six common SNPs related to body iron status from recent genome-wide association (GWA) studies were determined in the Nurses ’ Health Study (NHS; 1,467 diabetic cases and 1,754 controls) and the Health Professionals Follow-up Study (HPFS; 1,124, diabetic cases and 1,298 controls). Plasma levels of ferritin,...

  17. Managing Potato Biodiversity to Cope with Frost Risk in the High Andes: A Modeling Perspective

    Bruno Condori; Robert J. Hijmans; Jean Francois Ledent; Roberto Quiroz
    Austral summer frosts in the Andean highlands are ubiquitous throughout the crop cycle, causing yield losses. In spite of the existing warming trend, climate change models forecast high variability, including freezing temperatures. As the potato center of origin, the region has a rich biodiversity which includes a set of frost resistant genotypes. Four contrasting potato genotypes –representing genetic variability- were considered in the present study: two species of frost resistant native potatoes (the bitter Solanum juzepczukii, var. Luki, and the non-bitter Solanum ajanhuiri, var. Ajanhuiri) and two commercial frost susceptible genotypes (Solanum tuberosum ssp. tuberosum var. Alpha and Solanum tuberosum...

  18. STUDY PROTOCOL Rationale, design and obje n

    Autosomal recessive polycystic kidney disease (ARPKD) is a rare, but severe form of polycystic kidney disease with unexplained phenotypic variability and a consider-able impact on affected patients and families as well as attending physicians. The disease is caused by mutations in a single gene, Polycystic Kidney and Hepatic Disease 1 (PKHD1) encoding a huge transmembrane protein of poorly understood function called fibrocystin (4074 amino acids) [1]. Fibrocystin localizes to primary cilia of cells, classifying ARPKD as ciliopathy [2]. Within the last years basic science approaches have brought tremendous progress in the understanding of the genetic basis and pathomechanisms of ciliopathies...

  19. High-throughput ethomics in large groups of Drosophila. Nature Methods. 2009; 6:451–457. [PubMed: 19412169

    Kristin Branson; Alice Robie; John Bender; Pietro Perona; Michael Dickinson
    We present a camera-based method for automatically quantifying the individual and social behaviors of fruit flies, Drosophila melanogaster, interacting within a planar arena. Our system includes machine vision algorithms that accurately track many individuals without swapping identities and classification algorithms that detect behaviors. The data may be represented as an ethogram that plots the time course of behaviors exhibited by each fly, or as a vector that concisely captures the statistical properties of all behaviors displayed within a given period. We found that behavioral differences between individuals are consistent over time and are sufficient to accurately predict gender and genotype....

  20. PD-1 modulates steady-state and infection-induced IL-10 production in vivo

    Cortez Mcberry; Ra Dias; Nathaniel Shryock; Kristin Lampe; Fredy R. S. Gutierrez; Louis Boon; De’broski R. Herbert; Julio Aliberti
    Programmed death-1 (PD-1) plays an important role in mediating immune tolerance throughmechanisms that remain unclear. Herein, we investigatedwhether PD-1 prevents excessive host tissue damage during infection with the protozoan parasite, Toxoplasma gondii. Surprisingly, our results demonstrate that PD-1-deficient mice have increased susceptibility to T. gondii, with increased parasite cyst counts along with reduced type-1 cytokine responses (IL-12 and IFN-γ). PD-1−/ − DCs showed no cell intrinsic defect in IL-12 production in vitro. Instead, PD-1 neutralization via genetic or pharmacological approaches resulted in a striking increase in IL-10 release, which impaired type-1-inflammation during infection. Our results indicate that the absence of...

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