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1.
Cell Rep ; 41(12): 111754, 2022 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-36543141

RESUMEN

Anelloviruses represent a major constituent of the commensal human virome; however, little is known about their immunobiology. Here, we present "AnelloScan," a T7 phage library representing the open reading frame 1 (ORF1), ORF2, ORF3, and torque teno virus (TTV)-derived apoptosis-inducing protein (TAIP) sequences of more than 800 human anelloviruses and profile the antibody reactivities of serum samples from a cross-sectional cohort of 156 subjects by using phage-immunoprecipitation sequencing (PhIP-Seq). A majority of anellovirus peptides are not reactive in any of the subjects tested (n = ∼28,000; ∼85% of the library). Antibody-reactive peptides are largely restricted to the C-terminal region of the capsid protein ORF1. Moreover, using a longitudinal cohort of matched blood-transfusion donors and recipients, we find that most transmitted anelloviruses do not elicit a detectable antibody reactivity in the recipient and that the remainder elicit delayed responses appearing ∼100-150 days after transfusion.


Asunto(s)
Anelloviridae , Torque teno virus , Humanos , Formación de Anticuerpos , Estudios Transversales , Torque teno virus/metabolismo , Proteínas de la Cápside/metabolismo
2.
Nature ; 606(7915): 754-760, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35614211

RESUMEN

Microbial communities and their associated bioactive compounds1-3 are often disrupted in conditions such as the inflammatory bowel diseases (IBD)4. However, even in well-characterized environments (for example, the human gastrointestinal tract), more than one-third of microbial proteins are uncharacterized and often expected to be bioactive5-7. Here we systematically identified more than 340,000 protein families as potentially bioactive with respect to gut inflammation during IBD, about half of which have not to our knowledge been functionally characterized previously on the basis of homology or experiment. To validate prioritized microbial proteins, we used a combination of metagenomics, metatranscriptomics and metaproteomics to provide evidence of bioactivity for a subset of proteins that are involved in host and microbial cell-cell communication in the microbiome; for example, proteins associated with adherence or invasion processes, and extracellular von Willebrand-like factors. Predictions from high-throughput data were validated using targeted experiments that revealed the differential immunogenicity of prioritized Enterobacteriaceae pilins and the contribution of homologues of von Willebrand factors to the formation of Bacteroides biofilms in a manner dependent on mucin levels. This methodology, which we term MetaWIBELE (workflow to identify novel bioactive elements in the microbiome), is generalizable to other environmental communities and human phenotypes. The prioritized results provide thousands of candidate microbial proteins that are likely to interact with the host immune system in IBD, thus expanding our understanding of potentially bioactive gene products in chronic disease states and offering a rational compendium of possible therapeutic compounds and targets.


Asunto(s)
Proteínas Bacterianas , Microbioma Gastrointestinal , Genes Microbianos , Enfermedades Inflamatorias del Intestino , Proteínas Bacterianas/análisis , Proteínas Bacterianas/genética , Enfermedad Crónica , Microbioma Gastrointestinal/genética , Humanos , Enfermedades Inflamatorias del Intestino/microbiología , Metagenómica , Proteómica , Reproducibilidad de los Resultados , Transcriptoma
3.
Microbiome ; 10(1): 53, 2022 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-35337386

RESUMEN

BACKGROUND: The understanding of how microbiomes assemble, function, and evolve requires metagenomic tools that can resolve microbiota compositions at the strain level. However, the identification and tracking of microbial strains in fecal metagenomes is challenging and available tools variably classify subspecies lineages, which affects their applicability to infer microbial persistence and transfer. RESULTS: We introduce SameStr, a bioinformatic tool that identifies shared strains in metagenomes by determining single-nucleotide variants (SNV) in species-specific marker genes, which are compared based on a maximum variant profile similarity. We validated SameStr on mock strain populations, available human fecal metagenomes from healthy individuals and newly generated data from recurrent Clostridioides difficile infection (rCDI) patients treated with fecal microbiota transplantation (FMT). SameStr demonstrated enhanced sensitivity to detect shared dominant and subdominant strains in related samples (where strain persistence or transfer would be expected) when compared to other tools, while being robust against false-positive shared strain calls between unrelated samples (where neither strain persistence nor transfer would be expected). We applied SameStr to identify strains that are stably maintained in fecal microbiomes of healthy adults over time (strain persistence) and that successfully engraft in rCDI patients after FMT (strain engraftment). Taxonomy-dependent strain persistence and engraftment frequencies were positively correlated, indicating that a specific core microbiota of intestinal species is adapted to be competitive both in healthy microbiomes and during post-FMT microbiome assembly. We explored other use cases for strain-level microbiota profiling, as a metagenomics quality control measure and to identify individuals based on the persisting core gut microbiota. CONCLUSION: SameStr provides for a robust identification of shared strains in metagenomic sequence data with sufficient specificity and sensitivity to examine strain persistence, transfer, and engraftment in human fecal microbiomes. Our findings identify a persisting healthy adult core gut microbiota, which should be further studied to shed light on microbiota contributions to chronic diseases. Video abstract.


Asunto(s)
Infecciones por Clostridium , Microbioma Gastrointestinal , Adulto , Infecciones por Clostridium/terapia , Trasplante de Microbiota Fecal , Heces , Microbioma Gastrointestinal/genética , Humanos , Metagenoma , Metagenómica , Resultado del Tratamiento
4.
Cell Host Microbe ; 29(8): 1305-1315.e6, 2021 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-34320399

RESUMEN

Anelloviruses are a ubiquitous component of healthy human viromes and remain highly prevalent after being acquired early in life. The full extent of "anellome" diversity and its evolutionary dynamics remain unexplored. We employed in-depth sequencing of blood-transfusion donor(s)-recipient pairs coupled with public genomic resources for a large-scale assembly of anellovirus genomes and used the data to characterize global and personal anellovirus diversity through time. The breadth of the anellome is much greater than previously appreciated, and individuals harbor unique anellomes and transmit lineages that can persist for several months within a diverse milieu of endemic host lineages. Anellovirus sequence diversity is shaped by extensive recombination at all levels of divergence, hindering traditional phylogenetic analyses. Our findings illuminate the transmission dynamics and vast diversity of anelloviruses and set the foundation for future studies to characterize their biology.


Asunto(s)
Anelloviridae/clasificación , Anelloviridae/genética , Infecciones por Virus ADN/virología , Filogenia , Viroma , Transfusión Sanguínea , Coinfección , Genoma Viral , Genómica , Humanos
5.
Sci Rep ; 10(1): 13828, 2020 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-32796896

RESUMEN

Wine is a globally produced, marketed and consumed alcoholic beverage, which is valued for its aromatic and qualitative complexity and variation. These properties are partially attributable to the bacterial involvement in the fermentation process. However, the organizational principles and dynamic changes of the bacterial wine microbiota remain poorly understood, especially in the context of red and white wine variations and environmental stress factors. Here, we determined relative and absolute bacterial microbiota compositions from six distinct cultivars during the first week of fermentation by quantitative and qualitative 16S rRNA gene amplification and amplicon sequencing. All wines harboured complex and variable bacterial communities, with Tatumella as the most abundant genus across all batches, but red wines were characterized by higher bacterial diversity and increased relative and absolute abundance of lactic and acetic acid bacteria (LAB/AAB) and bacterial taxa of predicted environmental origin. Microbial diversity was positively correlated with plant-derived DNA concentrations in the wine and Botrytis cinerea infection before harvest. Our findings suggest that exogenous factors, such as procedural differences between red and white wine production and environmental stress on grape integrity, can increase bacterial diversity and specific bacterial taxa in wine, with potential consequences for wine quality and aroma.


Asunto(s)
Botrytis , Color , Productos Agrícolas/microbiología , ADN de Plantas , Gammaproteobacteria , Vitis/microbiología , Vino/microbiología , Calidad de los Alimentos
6.
Gastroenterology ; 158(5): 1313-1325, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31972239

RESUMEN

BACKGROUND & AIMS: Sulfur-metabolizing microbes, which convert dietary sources of sulfur into genotoxic hydrogen sulfide (H2S), have been associated with development of colorectal cancer (CRC). We identified a dietary pattern associated with sulfur-metabolizing bacteria in stool and then investigated its association with risk of incident CRC using data from a large prospective study of men. METHODS: We collected data from 51,529 men enrolled in the Health Professionals Follow-up Study since 1986 to determine the association between sulfur-metabolizing bacteria in stool and risk of CRC over 26 years of follow-up. First, in a subcohort of 307 healthy men, we profiled serial stool metagenomes and metatranscriptomes and assessed diet using semiquantitative food frequency questionnaires to identify food groups associated with 43 bacterial species involved in sulfur metabolism. We used these data to develop a sulfur microbial dietary score. We then used Cox proportional hazards modeling to evaluate adherence to this pattern among eligible individuals (n = 48,246) from 1986 through 2012 with risk for incident CRC. RESULTS: Foods associated with higher sulfur microbial diet scores included increased consumption of processed meats and low-calorie drinks and lower consumption of vegetables and legumes. Increased sulfur microbial diet scores were associated with risk of distal colon and rectal cancers, after adjusting for other risk factors (multivariable relative risk, highest vs lowest quartile, 1.43; 95% confidence interval 1.14-1.81; P-trend = .002). In contrast, sulfur microbial diet scores were not associated with risk of proximal colon cancer (multivariable relative risk 0.86; 95% CI 0.65-1.14; P-trend = .31). CONCLUSIONS: In an analysis of participants in the Health Professionals Follow-up Study, we found that long-term adherence to a dietary pattern associated with sulfur-metabolizing bacteria in stool was associated with an increased risk of distal CRC. Further studies are needed to determine how sulfur-metabolizing bacteria might contribute to CRC pathogenesis.


Asunto(s)
Bacterias/metabolismo , Neoplasias Colorrectales/epidemiología , Heces/microbiología , Conducta Alimentaria/fisiología , Microbioma Gastrointestinal/fisiología , Anciano , Bacterias/aislamiento & purificación , Neoplasias Colorrectales/microbiología , Neoplasias Colorrectales/prevención & control , Encuestas sobre Dietas/estadística & datos numéricos , Estudios de Seguimiento , Personal de Salud/estadística & datos numéricos , Humanos , Incidencia , Masculino , Massachusetts/epidemiología , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Azufre/metabolismo
7.
Nature ; 569(7758): 655-662, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31142855

RESUMEN

Inflammatory bowel diseases, which include Crohn's disease and ulcerative colitis, affect several million individuals worldwide. Crohn's disease and ulcerative colitis are complex diseases that are heterogeneous at the clinical, immunological, molecular, genetic, and microbial levels. Individual contributing factors have been the focus of extensive research. As part of the Integrative Human Microbiome Project (HMP2 or iHMP), we followed 132 subjects for one year each to generate integrated longitudinal molecular profiles of host and microbial activity during disease (up to 24 time points each; in total 2,965 stool, biopsy, and blood specimens). Here we present the results, which provide a comprehensive view of functional dysbiosis in the gut microbiome during inflammatory bowel disease activity. We demonstrate a characteristic increase in facultative anaerobes at the expense of obligate anaerobes, as well as molecular disruptions in microbial transcription (for example, among clostridia), metabolite pools (acylcarnitines, bile acids, and short-chain fatty acids), and levels of antibodies in host serum. Periods of disease activity were also marked by increases in temporal variability, with characteristic taxonomic, functional, and biochemical shifts. Finally, integrative analysis identified microbial, biochemical, and host factors central to this dysregulation. The study's infrastructure resources, results, and data, which are available through the Inflammatory Bowel Disease Multi'omics Database ( http://ibdmdb.org ), provide the most comprehensive description to date of host and microbial activities in inflammatory bowel diseases.


Asunto(s)
Microbioma Gastrointestinal/genética , Enfermedades Inflamatorias del Intestino/microbiología , Animales , Hongos/patogenicidad , Microbioma Gastrointestinal/inmunología , Salud , Humanos , Enfermedades Inflamatorias del Intestino/inmunología , Enfermedades Inflamatorias del Intestino/terapia , Enfermedades Inflamatorias del Intestino/virología , Filogenia , Especificidad de la Especie , Transcriptoma , Virus/patogenicidad
9.
BMC Genomics ; 18(1): 332, 2017 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-28449639

RESUMEN

BACKGROUND: The benefit of increasing genomic sequence data to the scientific community depends on easy-to-use, scalable bioinformatics support. CloVR-Comparative combines commonly used bioinformatics tools into an intuitive, automated, and cloud-enabled analysis pipeline for comparative microbial genomics. RESULTS: CloVR-Comparative runs on annotated complete or draft genome sequences that are uploaded by the user or selected via a taxonomic tree-based user interface and downloaded from NCBI. CloVR-Comparative runs reference-free multiple whole-genome alignments to determine unique, shared and core coding sequences (CDSs) and single nucleotide polymorphisms (SNPs). Output includes short summary reports and detailed text-based results files, graphical visualizations (phylogenetic trees, circular figures), and a database file linked to the Sybil comparative genome browser. Data up- and download, pipeline configuration and monitoring, and access to Sybil are managed through CloVR-Comparative web interface. CloVR-Comparative and Sybil are distributed as part of the CloVR virtual appliance, which runs on local computers or the Amazon EC2 cloud. Representative datasets (e.g. 40 draft and complete Escherichia coli genomes) are processed in <36 h on a local desktop or at a cost of <$20 on EC2. CONCLUSIONS: CloVR-Comparative allows anybody with Internet access to run comparative genomics projects, while eliminating the need for on-site computational resources and expertise.


Asunto(s)
Nube Computacional , Genómica/métodos , Programas Informáticos , Automatización , Genoma Microbiano/genética , Alineación de Secuencia , Análisis de Secuencia
10.
Nat Commun ; 6: 8754, 2015 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-26515720

RESUMEN

Understanding the molecular parameters that regulate cross-species transmission and host adaptation of potential pathogens is crucial to control emerging infectious disease. Although microbial pathotype diversity is conventionally associated with gene gain or loss, the role of pathoadaptive nonsynonymous single-nucleotide polymorphisms (nsSNPs) has not been systematically evaluated. Here, our genome-wide analysis of core genes within Salmonella enterica serovar Typhimurium genomes reveals a high degree of allelic variation in surface-exposed molecules, including adhesins that promote host colonization. Subsequent multinomial logistic regression, MultiPhen and Random Forest analyses of known/suspected adhesins from 580 independent Typhimurium isolates identifies distinct host-specific nsSNP signatures. Moreover, population and functional analyses of host-associated nsSNPs for FimH, the type 1 fimbrial adhesin, highlights the role of key allelic residues in host-specific adherence in vitro. Together, our data provide the first concrete evidence that functional differences between allelic variants of bacterial proteins likely contribute to pathoadaption to diverse hosts.


Asunto(s)
Adhesinas Bacterianas/genética , Proteínas Bacterianas/genética , Variación Genética , Especificidad del Huésped , Salmonelosis Animal/microbiología , Infecciones por Salmonella/microbiología , Salmonella typhimurium/genética , Adhesinas Bacterianas/química , Adhesinas Bacterianas/metabolismo , Alelos , Secuencia de Aminoácidos , Animales , Adhesión Bacteriana , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Fimbrias Bacterianas/química , Fimbrias Bacterianas/genética , Fimbrias Bacterianas/metabolismo , Microbiología de Alimentos , Humanos , Datos de Secuencia Molecular , Filogenia , Polimorfismo de Nucleótido Simple , Salmonella typhimurium/clasificación , Salmonella typhimurium/aislamiento & purificación , Salmonella typhimurium/fisiología
11.
Mol Biol Evol ; 32(5): 1354-64, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25589738

RESUMEN

Species in the genus Plasmodium cause malaria in humans and infect a variety of mammals and other vertebrates. Currently, estimated ages for several mammalian Plasmodium parasites differ by as much as one order of magnitude, an inaccuracy that frustrates reliable estimation of evolutionary rates of disease-related traits. We developed a novel statistical approach to dating the relative age of evolutionary lineages, based on Total Least Squares regression. We validated this lineage dating approach by applying it to the genus Drosophila. Using data from the Drosophila 12 Genomes project, our approach accurately reconstructs the age of well-established Drosophila clades, including the speciation event that led to the subgenera Drosophila and Sophophora, and age of the melanogaster species subgroup. We applied this approach to hundreds of loci from seven mammalian Plasmodium species. We demonstrate the existence of a molecular clock specific to individual Plasmodium proteins, and estimate the relative age of mammalian-infecting Plasmodium. These analyses indicate that: 1) the split between the human parasite Plasmodium vivax and P. knowlesi, from Old World monkeys, occurred 6.1 times earlier than that between P. falciparum and P. reichenowi, parasites of humans and chimpanzees, respectively; and 2) mammalian Plasmodium parasites originated 22 times earlier than the split between P. falciparum and P. reichenowi. Calibrating the absolute divergence times for Plasmodium with eukaryotic substitution rates, we show that the split between P. falciparum and P. reichenowi occurred 3.0-5.5 Ma, and that mammalian Plasmodium parasites originated over 64 Ma. Our results indicate that mammalian-infecting Plasmodium evolved contemporaneously with their hosts, with little evidence for parasite host-switching on an evolutionary scale, and provide a solid timeframe within which to place the evolution of new Plasmodium species.


Asunto(s)
Evolución Molecular , Interacciones Huésped-Parásitos/genética , Malaria Falciparum/genética , Plasmodium falciparum/genética , Animales , Humanos , Malaria Falciparum/parasitología , Pan troglodytes/genética , Filogenia , Plasmodium falciparum/patogenicidad , Plasmodium vivax/genética , Plasmodium vivax/patogenicidad , Alineación de Secuencia
12.
J Infect Dis ; 211(5): 670-9, 2015 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-25180241

RESUMEN

BACKGROUND: The emergence of artemisinin-resistant Plasmodium falciparum in Southeast Asia threatens malaria treatment efficacy. Mutations in a kelch protein encoded on P. falciparum chromosome 13 (K13) have been associated with resistance in vitro and in field samples from Cambodia. METHODS: P. falciparum infections from artesunate efficacy trials in Bangladesh, Cambodia, Laos, Myanmar, and Vietnam were genotyped at 33 716 genome-wide single-nucleotide polymorphisms (SNPs). Linear mixed models were used to test associations between parasite genotypes and parasite clearance half-lives following artesunate treatment. K13 mutations were tested for association with artemisinin resistance, and extended haplotypes on chromosome 13 were examined to determine whether mutations arose focally and spread or whether they emerged independently. RESULTS: The presence of nonreference K13 alleles was associated with prolonged parasite clearance half-life (P = 1.97 × 10(-12)). Parasites with a mutation in any of the K13 kelch domains displayed longer parasite clearance half-lives than parasites with wild-type alleles. Haplotype analysis revealed both population-specific emergence of mutations and independent emergence of the same mutation in different geographic areas. CONCLUSIONS: K13 appears to be a major determinant of artemisinin resistance throughout Southeast Asia. While we found some evidence of spreading resistance, there was no evidence of resistance moving westward from Cambodia into Myanmar.


Asunto(s)
Antimaláricos/farmacología , Artemisininas/farmacología , Resistencia a Medicamentos , Malaria Falciparum/parasitología , Mutación , Plasmodium falciparum/efectos de los fármacos , Asia Sudoriental , Genotipo , Humanos , Plasmodium falciparum/genética , Plasmodium falciparum/aislamiento & purificación , Polimorfismo de Nucleótido Simple , Proteínas Protozoarias/genética
13.
Nucleic Acids Res ; 43(Database issue): D1071-8, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25348409

RESUMEN

The current version of the Human Disease Ontology (DO) (http://www.disease-ontology.org) database expands the utility of the ontology for the examination and comparison of genetic variation, phenotype, protein, drug and epitope data through the lens of human disease. DO is a biomedical resource of standardized common and rare disease concepts with stable identifiers organized by disease etiology. The content of DO has had 192 revisions since 2012, including the addition of 760 terms. Thirty-two percent of all terms now include definitions. DO has expanded the number and diversity of research communities and community members by 50+ during the past two years. These community members actively submit term requests, coordinate biomedical resource disease representation and provide expert curation guidance. Since the DO 2012 NAR paper, there have been hundreds of term requests and a steady increase in the number of DO listserv members, twitter followers and DO website usage. DO is moving to a multi-editor model utilizing Protégé to curate DO in web ontology language. This will enable closer collaboration with the Human Phenotype Ontology, EBI's Ontology Working Group, Mouse Genome Informatics and the Monarch Initiative among others, and enhance DO's current asserted view and multiple inferred views through reasoning.


Asunto(s)
Ontologías Biológicas , Bases de Datos Factuales , Enfermedad , Enfermedades Genéticas Congénitas , Humanos , Internet , Enfermedades Raras/genética
14.
Am J Trop Med Hyg ; 91(4): 833-843, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25048375

RESUMEN

Adequate clinical and parasitologic cure by artemisinin combination therapies relies on the artemisinin component and the partner drug. Polymorphisms in the Plasmodium falciparum chloroquine resistance transporter (pfcrt) and P. falciparum multidrug resistance 1 (pfmdr1) genes are associated with decreased sensitivity to amodiaquine and lumefantrine, but effects of these polymorphisms on therapeutic responses to artesunate-amodiaquine (ASAQ) and artemether-lumefantrine (AL) have not been clearly defined. Individual patient data from 31 clinical trials were harmonized and pooled by using standardized methods from the WorldWide Antimalarial Resistance Network. Data for more than 7,000 patients were analyzed to assess relationships between parasite polymorphisms in pfcrt and pfmdr1 and clinically relevant outcomes after treatment with AL or ASAQ. Presence of the pfmdr1 gene N86 (adjusted hazards ratio = 4.74, 95% confidence interval = 2.29 - 9.78, P < 0.001) and increased pfmdr1 copy number (adjusted hazards ratio = 6.52, 95% confidence interval = 2.36-17.97, P < 0.001 : were significant independent risk factors for recrudescence in patients treated with AL. AL and ASAQ exerted opposing selective effects on single-nucleotide polymorphisms in pfcrt and pfmdr1. Monitoring selection and responding to emerging signs of drug resistance are critical tools for preserving efficacy of artemisinin combination therapies; determination of the prevalence of at least pfcrt K76T and pfmdr1 N86Y should now be routine.


Asunto(s)
Antimaláricos/uso terapéutico , Malaria Falciparum/parasitología , Proteínas de Transporte de Membrana/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Plasmodium falciparum/genética , Polimorfismo Genético , Proteínas Protozoarias/genética , Sustitución de Aminoácidos , Amodiaquina/uso terapéutico , Antimaláricos/farmacología , Arteméter , Artemisininas/uso terapéutico , Niño , Preescolar , Cloroquina/farmacología , Conjuntos de Datos como Asunto , Combinación de Medicamentos , Resistencia a Medicamentos/genética , Quimioterapia Combinada , Etanolaminas/uso terapéutico , Fluorenos/uso terapéutico , Marcadores Genéticos/genética , Genotipo , Humanos , Lactante , Estimación de Kaplan-Meier , Lumefantrina , Malaria Falciparum/tratamiento farmacológico , Plasmodium falciparum/efectos de los fármacos , Factores de Riesgo
15.
Proc Natl Acad Sci U S A ; 110(1): 240-5, 2013 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-23248304

RESUMEN

The recent emergence of artemisinin-resistant Plasmodium falciparum malaria in western Cambodia could threaten prospects for malaria elimination. Identification of the genetic basis of resistance would provide tools for molecular surveillance, aiding efforts to contain resistance. Clinical trials of artesunate efficacy were conducted in Bangladesh, in northwestern Thailand near the Myanmar border, and at two sites in western Cambodia. Parasites collected from trial participants were genotyped at 8,079 single nucleotide polymorphisms (SNPs) using a P. falciparum-specific SNP array. Parasite genotypes were examined for signatures of recent positive selection and association with parasite clearance phenotypes to identify regions of the genome associated with artemisinin resistance. Four SNPs on chromosomes 10 (one), 13 (two), and 14 (one) were significantly associated with delayed parasite clearance. The two SNPs on chromosome 13 are in a region of the genome that appears to be under strong recent positive selection in Cambodia. The SNPs on chromosomes 10 and 13 lie in or near genes involved in postreplication repair, a DNA damage-tolerance pathway. Replication and validation studies are needed to refine the location of loci responsible for artemisinin resistance and to understand the mechanism behind it; however, two SNPs on chromosomes 10 and 13 may be useful markers of delayed parasite clearance in surveillance for artemisinin resistance in Southeast Asia.


Asunto(s)
Artemisininas/farmacología , Resistencia a Medicamentos/genética , Sitios Genéticos/genética , Plasmodium falciparum/genética , Selección Genética , Asia Sudoriental , Marcadores Genéticos/genética , Genotipo , Funciones de Verosimilitud , Oportunidad Relativa , Análisis de Secuencia por Matrices de Oligonucleótidos , Polimorfismo de Nucleótido Simple/genética , Análisis de Componente Principal , Análisis de Regresión
16.
Nucleic Acids Res ; 40(Database issue): D940-6, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22080554

RESUMEN

The Disease Ontology (DO) database (http://disease-ontology.org) represents a comprehensive knowledge base of 8043 inherited, developmental and acquired human diseases (DO version 3, revision 2510). The DO web browser has been designed for speed, efficiency and robustness through the use of a graph database. Full-text contextual searching functionality using Lucene allows the querying of name, synonym, definition, DOID and cross-reference (xrefs) with complex Boolean search strings. The DO semantically integrates disease and medical vocabularies through extensive cross mapping and integration of MeSH, ICD, NCI's thesaurus, SNOMED CT and OMIM disease-specific terms and identifiers. The DO is utilized for disease annotation by major biomedical databases (e.g. Array Express, NIF, IEDB), as a standard representation of human disease in biomedical ontologies (e.g. IDO, Cell line ontology, NIFSTD ontology, Experimental Factor Ontology, Influenza Ontology), and as an ontological cross mappings resource between DO, MeSH and OMIM (e.g. GeneWiki). The DO project (http://diseaseontology.sf.net) has been incorporated into open source tools (e.g. Gene Answers, FunDO) to connect gene and disease biomedical data through the lens of human disease. The next iteration of the DO web browser will integrate DO's extended relations and logical definition representation along with these biomedical resource cross-mappings.


Asunto(s)
Bases de Datos Factuales , Enfermedad/clasificación , Gráficos por Computador , Enfermedad/etiología , Humanos , Semántica , Programas Informáticos , Terminología como Asunto , Interfaz Usuario-Computador , Vocabulario Controlado
17.
BMC Bioinformatics ; 12: 356, 2011 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-21878105

RESUMEN

BACKGROUND: Next-generation sequencing technologies have decentralized sequence acquisition, increasing the demand for new bioinformatics tools that are easy to use, portable across multiple platforms, and scalable for high-throughput applications. Cloud computing platforms provide on-demand access to computing infrastructure over the Internet and can be used in combination with custom built virtual machines to distribute pre-packaged with pre-configured software. RESULTS: We describe the Cloud Virtual Resource, CloVR, a new desktop application for push-button automated sequence analysis that can utilize cloud computing resources. CloVR is implemented as a single portable virtual machine (VM) that provides several automated analysis pipelines for microbial genomics, including 16S, whole genome and metagenome sequence analysis. The CloVR VM runs on a personal computer, utilizes local computer resources and requires minimal installation, addressing key challenges in deploying bioinformatics workflows. In addition CloVR supports use of remote cloud computing resources to improve performance for large-scale sequence processing. In a case study, we demonstrate the use of CloVR to automatically process next-generation sequencing data on multiple cloud computing platforms. CONCLUSION: The CloVR VM and associated architecture lowers the barrier of entry for utilizing complex analysis protocols on both local single- and multi-core computers and cloud systems for high throughput data processing.


Asunto(s)
Computadores , Internet , Análisis de Secuencia de ADN , Programas Informáticos , Biología Computacional , Genómica , Secuenciación de Nucleótidos de Alto Rendimiento
18.
Nucleic Acids Res ; 38(Database issue): D754-64, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19850722

RESUMEN

The Gemina system (http://gemina.igs.umaryland.edu) identifies, standardizes and integrates the outbreak metadata for the breadth of NIAID category A-C viral and bacterial pathogens, thereby providing an investigative and surveillance tool describing the Who [Host], What [Disease, Symptom], When [Date], Where [Location] and How [Pathogen, Environmental Source, Reservoir, Transmission Method] for each pathogen. The Gemina database will provide a greater understanding of the interactions of viral and bacterial pathogens with their hosts and infectious diseases through in-depth literature text-mining, integrated outbreak metadata, outbreak surveillance tools, extensive ontology development, metadata curation and representative genomic sequence identification and standards development. The Gemina web interface provides metadata selection and retrieval of a pathogen's; Infection Systems (Pathogen, Host, Disease, Transmission Method and Anatomy) and Incidents (Location and Date) along with a hosts Age and Gender. The Gemina system provides an integrated investigative and geospatial surveillance system connecting pathogens, pathogen products and disease anchored on the taxonomic ID of the pathogen and host to identify the breadth of hosts and diseases known for these pathogens, to identify the extent of outbreak locations, and to identify unique genomic regions with the DNA Signature Insignia Detection Tool.


Asunto(s)
Enfermedades Transmisibles/microbiología , Biología Computacional/métodos , Bases de Datos Genéticas , Bases de Datos de Ácidos Nucleicos , Genes Bacterianos , Genes Virales , Animales , Infecciones Bacterianas/microbiología , Enfermedades Transmisibles/virología , Biología Computacional/tendencias , Bases de Datos Factuales , Humanos , Almacenamiento y Recuperación de la Información/métodos , Internet , Programas Informáticos , Interfaz Usuario-Computador , Virosis/virología
19.
Cochabamba; s.n; 200103. 58 p. ^empastado.
Tesis en Español | LIBOCS, LIBOSP | ID: biblio-1307976

RESUMEN

El conocimiento de la farmacología y la farmacoterapia bien fundamentada, es una parte esencial de la formación médica, pero es importante que el enfoque de estos conocimientos no este centrado exclusivamente en los fármacos y diagnósticos, si no también en la terapeútica, para fortalecer las capacidades prescriptivas con un pensamiento crítico que permita a los estudiantes un análisis de sus tratamientos. Si los estudiantes o los médicos egresados carecen de los fundamentos de la farmacología y de la terapeútica, las probabilidades de prescripciones irracionales son mayores, con las consecuencias de tratamientos inefectivos e inseguros, con exacerbaciones o alargamientos de la enfermedad, incremento de los costos y tensión y daño para los pacientes. Todos los medicamentos tienen efectos físicos en el paciente como ser los efectos colaterales, efectos psicológicos ya que se considera que sin medicación ninguna patología pueda ser tratada y uno de los grandes retos del medio es la de que el paciente salga sin receta de un consultorio, considerando que no todos los procesos morbosos se solucionaran con trataminto medicamentosos y el ultimo problema es el social debido a que los costos no son accesibles a la mayor parte de la población, lo que determina que existe inequidad en los tratamientos.


Asunto(s)
Educación , Farmacología , Estudiantes
20.
Cochabamba; s.n; 200103. 58 p. ^empastado.
Tesis en Español | LIBOCS, LIBOSP | ID: biblio-1307977

RESUMEN

El conocimiento de la farmacología y la farmacoterapia bien fundamentada, es una parte esencial de la formación médica, pero es importante que el enfoque de estos conocimientos no este centrado exclusivamente en los fármacos y diagnósticos, si no también en la terapeútica, para fortalecer las capacidades prescriptivas con un pensamiento crítico que permita a los estudiantes un análisis de sus tratamientos. Si los estudiantes o los médicos egresados carecen de los fundamentos de la farmacología y de la terapeútica, las probabilidades de prescripciones irracionales son mayores, con las consecuencias de tratamientos inefectivos e inseguros, con exacerbaciones o alargamientos de la enfermedad, incremento de los costos y tensión y daño para los pacientes. Todos los medicamentos tienen efectos físicos en el paciente como ser los efectos colaterales, efectos psicológicos ya que se considera que sin medicación ninguna patología pueda ser tratada y uno de los grandes retos del medio es la de que el paciente salga sin receta de un consultorio, considerando que no todos los procesos morbosos se solucionaran con trataminto medicamentosos y el ultimo problema es el social debido a que los costos no son accesibles a la mayor parte de la población, lo que determina que existe inequidad en los tratamientos.


Asunto(s)
Educación , Farmacología , Estudiantes
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