Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 61
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Ann Intern Med ; 168(8): 550-557, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29532054

RESUMO

Background: Screening for colorectal cancer (CRC) reduces mortality, yet more than one third of age-eligible Americans are unscreened. Objective: To examine the effect of a digital health intervention, Mobile Patient Technology for Health-CRC (mPATH-CRC), on rates of CRC screening. Design: Randomized clinical trial. (ClinicalTrials.gov: NCT02088333). Setting: 6 community-based primary care practices. Participants: 450 patients (223 in the mPATH-CRC group and 227 in usual care) scheduled for a primary care visit and due for routine CRC screening. Intervention: An iPad application that displays a CRC screening decision aid, lets patients order their own screening tests, and sends automated follow-up electronic messages to support patients. Measurements: The primary outcome was chart-verified completion of CRC screening within 24 weeks. Secondary outcomes were ability to state a screening preference, intention to receive screening, screening discussions, and orders for screening tests. All outcome assessors were blinded to randomization. Results: Baseline characteristics were similar between groups; 37% of participants had limited health literacy, and 53% had annual incomes less than $20 000. Screening was completed by 30% of mPATH-CRC participants and 15% of those receiving usual care (logistic regression odds ratio, 2.5 [95% CI, 1.6 to 4.0]). Compared with usual care, more mPATH-CRC participants could state a screening preference, planned to be screened within 6 months, discussed screening with their provider, and had a screening test ordered. Half of mPATH-CRC participants (53%; 118 of 223) "self-ordered" a test via the program. Limitation: Participants were English speakers in a single health care system. Conclusion: A digital health intervention that allows patients to self-order tests can increase CRC screening. Future research should identify methods for implementing similar interventions in clinical care. Primary Funding Source: National Cancer Institute.


Assuntos
Neoplasias Colorretais/diagnóstico , Detecção Precoce de Câncer/métodos , Programas de Rastreamento/métodos , Aplicativos Móveis , Populações Vulneráveis , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atenção Primária à Saúde , Estados Unidos
2.
J Anim Ecol ; 86(6): 1469-1482, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28884827

RESUMO

Heterogeneity within pathogen species can have important consequences for how pathogens transmit across landscapes; however, discerning different transmission routes is challenging. Here, we apply both phylodynamic and phylogenetic community ecology techniques to examine the consequences of pathogen heterogeneity on transmission by assessing subtype-specific transmission pathways in a social carnivore. We use comprehensive social and spatial network data to examine transmission pathways for three subtypes of feline immunodeficiency virus (FIVPle ) in African lions (Panthera leo) at multiple scales in the Serengeti National Park, Tanzania. We used FIVPle molecular data to examine the role of social organization and lion density in shaping transmission pathways and tested to what extent vertical (i.e., father- and/or mother-offspring relationships) or horizontal (between unrelated individuals) transmission underpinned these patterns for each subtype. Using the same data, we constructed subtype-specific FIVPle co-occurrence networks and assessed what combination of social networks, spatial networks or co-infection best structured the FIVPle network. While social organization (i.e., pride) was an important component of FIVPle transmission pathways at all scales, we find that FIVPle subtypes exhibited different transmission pathways at within- and between-pride scales. A combination of social and spatial networks, coupled with consideration of subtype co-infection, was likely to be important for FIVPle transmission for the two major subtypes, but the relative contribution of each factor was strongly subtype-specific. Our study provides evidence that pathogen heterogeneity is important in understanding pathogen transmission, which could have consequences for how endemic pathogens are managed. Furthermore, we demonstrate that community phylogenetic ecology coupled with phylodynamic techniques can reveal insights into the differential evolutionary pressures acting on virus subtypes, which can manifest into landscape-level effects.


Assuntos
Coinfecção/veterinária , Vírus da Imunodeficiência Felina/fisiologia , Infecções por Lentivirus/veterinária , Leões , Animais , Coinfecção/transmissão , Coinfecção/virologia , Vírus da Imunodeficiência Felina/classificação , Infecções por Lentivirus/transmissão , Infecções por Lentivirus/virologia , Leões/fisiologia , Filogenia , Comportamento Social , Tanzânia
3.
J Health Polit Policy Law ; 41(2): 157-79, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26732315

RESUMO

The pharmaceutical industry has been criticized for developing and aggressively marketing drugs that do not provide significant health benefits relative to existing drugs but retain the benefits of patent protection. Critics argue that drug marketing increases health care expenditures and provides a disincentive for pioneering drug innovation. However, evidence that marketing expenditures have any relationship to new drug approvals has been anecdotal. We hypothesized that, at publicly traded pharmaceutical firms, increased marketing expenditures will result in a reduced volume of pioneering new drugs in comparison to less innovative new drugs. We also hypothesized that additional research and development spending will result in an increased volume of pioneering new drugs in comparison to less innovative drugs. Results confirm our hypotheses. Specific policy recommendations for altering firms' incentives for the development of pioneering drugs are provided.


Assuntos
Difusão de Inovações , Aprovação de Drogas/estatística & dados numéricos , Indústria Farmacêutica/economia , Marketing/economia , Humanos , Estados Unidos , United States Food and Drug Administration
4.
J Virol ; 88(14): 7727-37, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24741092

RESUMO

Mountain lions (Puma concolor) throughout North and South America are infected with puma lentivirus clade B (PLVB). A second, highly divergent lentiviral clade, PLVA, infects mountain lions in southern California and Florida. Bobcats (Lynx rufus) in these two geographic regions are also infected with PLVA, and to date, this is the only strain of lentivirus identified in bobcats. We sequenced full-length PLV genomes in order to characterize the molecular evolution of PLV in bobcats and mountain lions. Low sequence homology (88% average pairwise identity) and frequent recombination (1 recombination breakpoint per 3 isolates analyzed) were observed in both clades. Viral proteins have markedly different patterns of evolution; sequence homology and negative selection were highest in Gag and Pol and lowest in Vif and Env. A total of 1.7% of sites across the PLV genome evolve under positive selection, indicating that host-imposed selection pressure is an important force shaping PLV evolution. PLVA strains are highly spatially structured, reflecting the population dynamics of their primary host, the bobcat. In contrast, the phylogeography of PLVB reflects the highly mobile mountain lion, with diverse PLVB isolates cocirculating in some areas and genetically related viruses being present in populations separated by thousands of kilometers. We conclude that PLVA and PLVB are two different viral species with distinct feline hosts and evolutionary histories. Importance: An understanding of viral evolution in natural host populations is a fundamental goal of virology, molecular biology, and disease ecology. Here we provide a detailed analysis of puma lentivirus (PLV) evolution in two natural carnivore hosts, the bobcat and mountain lion. Our results illustrate that PLV evolution is a dynamic process that results from high rates of viral mutation/recombination and host-imposed selection pressure.


Assuntos
Genoma Viral , Vírus da Imunodeficiência Felina/isolamento & purificação , Lynx/virologia , Puma/virologia , RNA Viral/genética , Análise de Sequência de DNA , Animais , Análise por Conglomerados , Evolução Molecular , Variação Genética , Vírus da Imunodeficiência Felina/classificação , Vírus da Imunodeficiência Felina/genética , Dados de Sequência Molecular , América do Norte , Filogeografia , Recombinação Genética , Seleção Genética , Proteínas Virais/genética
5.
PLoS Genet ; 8(11): e1003103, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23209447

RESUMO

Nasopharyngeal carcinoma (NPC) is an epithelial malignancy facilitated by Epstein-Barr Virus infection. Here we resolve the major genetic influences for NPC incidence using a genome-wide association study (GWAS), independent cohort replication, and high-resolution molecular HLA class I gene typing including 4,055 study participants from the Guangxi Zhuang Autonomous Region and Guangdong province of southern China. We detect and replicate strong association signals involving SNPs, HLA alleles, and amino acid (aa) variants across the major histocompatibility complex-HLA-A, HLA -B, and HLA -C class I genes (P(HLA-A-aa-site-62) = 7.4 × 10(-29); P (HLA-B-aa-site-116) = 6.5 × 10(-19); P (HLA-C-aa-site-156) = 6.8 × 10(-8) respectively). Over 250 NPC-HLA associated variants within HLA were analyzed in concert to resolve separate and largely independent HLA-A, -B, and -C gene influences. Multivariate logistical regression analysis collapsed significant associations in adjacent genes spanning 500 kb (OR2H1, GABBR1, HLA-F, and HCG9) as proxies for peptide binding motifs carried by HLA- A*11:01. A similar analysis resolved an independent association signal driven by HLA-B*13:01, B*38:02, and B*55:02 alleles together. NPC resistance alleles carrying the strongly associated amino acid variants implicate specific class I peptide recognition motifs in HLA-A and -B peptide binding groove as conferring strong genetic influence on the development of NPC in China.


Assuntos
Estudo de Associação Genômica Ampla , Antígenos HLA-A , Antígenos HLA-B , Neoplasias Nasofaríngeas , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Povo Asiático , Carcinoma , China , Feminino , Predisposição Genética para Doença , Antígenos HLA-A/genética , Antígenos HLA-A/imunologia , Antígenos HLA-B/genética , Antígenos HLA-B/imunologia , Antígenos HLA-C/genética , Antígenos HLA-C/imunologia , Haplótipos , Herpesvirus Humano 4 , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/imunologia , Polimorfismo de Nucleotídeo Único
6.
PLoS Genet ; 7(10): e1002328, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22046140

RESUMO

Chromosome 3p21-22 harbors two clusters of chemokine receptor genes, several of which serve as major or minor coreceptors of HIV-1. Although the genetic association of CCR5 and CCR2 variants with HIV-1 pathogenesis is well known, the role of variation in other nearby chemokine receptor genes remain unresolved. We genotyped exonic single nucleotide polymorphisms (SNPs) in chemokine receptor genes: CCR3, CCRL2, and CXCR6 (at 3p21) and CCR8 and CX3CR1 (at 3p22), the majority of which were non-synonymous. The individual SNPs were tested for their effects on disease progression and outcomes in five treatment-naïve HIV-1/AIDS natural history cohorts. In addition to the known CCR5 and CCR2 associations, significant associations were identified for CCR3, CCR8, and CCRL2 on progression to AIDS. A multivariate survival analysis pointed to a previously undetected association of a non-conservative amino acid change F167Y in CCRL2 with AIDS progression: 167F is associated with accelerated progression to AIDS (RH = 1.90, P = 0.002, corrected). Further analysis indicated that CCRL2-167F was specifically associated with more rapid development of pneumocystis pneumonia (PCP) (RH = 2.84, 95% CI 1.28-6.31) among four major AIDS-defining conditions. Considering the newly defined role of CCRL2 in lung dendritic cell trafficking, this atypical chemokine receptor may affect PCP through immune regulation and inducing inflammation.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , HIV-1 , Pneumonia por Pneumocystis/genética , Receptores CCR/química , Receptores CCR/genética , Cromossomos Humanos Par 3/genética , Estudos de Coortes , Progressão da Doença , Éxons , Estudos de Associação Genética , Células HEK293 , Humanos , Desequilíbrio de Ligação , Pneumonia por Pneumocystis/etiologia , Polimorfismo de Nucleotídeo Único , Receptores CCR3/genética , Receptores CCR8/genética , Receptores CXCR6 , Receptores de Quimiocinas/genética , Receptores Virais/genética , Análise de Sobrevida , Resultado do Tratamento
7.
Health Care Manage Rev ; 39(4): 340-51, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24153027

RESUMO

BACKGROUND: Older adults are at greatest risk of medication errors during the transition period of the first 7 days after admission and readmission to a skilled nursing facility (SNF). PURPOSE: The aim of this study was to evaluate structure- and process-related factors that contribute to medication errors and harm during transition periods at a SNF. METHODOLOGY/APPROACH: Data for medication errors and potential medication errors during the 7-day transition period for residents entering North Carolina SNFs were from the Medication Error Quality Initiative-Individual Error database from October 2006 to September 2007. The impact of SNF structure and process measures on the number of reported medication errors and harm from errors were examined using bivariate and multivariate model methods. FINDINGS: A total of 138 SNFs reported 581 transition period medication errors; 73 (12.6%) caused harm. Chain affiliation was associated with a reduction in the volume of errors during the transition period. One third of all reported transition errors occurred during the medication administration phase of the medication use process, where dose omissions were the most common type of error; however, dose omissions caused harm less often than wrong-dose errors did. Prescribing errors were much less common than administration errors but were much more likely to cause harm. PRACTICE IMPLICATIONS: Both structure and process measures of quality were related to the volume of medication errors.However, process quality measures may play a more important role in predicting harm from errors during the transition of a resident into an SNF. Medication errors during transition could be reduced by improving both prescribing processes and transcription and documentation of orders.


Assuntos
Erros de Medicação/estatística & dados numéricos , Casas de Saúde/estatística & dados numéricos , Recursos Humanos de Enfermagem/organização & administração , Admissão do Paciente , Idoso , Humanos , Erros de Medicação/efeitos adversos , Casas de Saúde/organização & administração , Casas de Saúde/normas , Recursos Humanos de Enfermagem/estatística & dados numéricos , Admissão do Paciente/normas
8.
Nat Genet ; 56(5): 752-757, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38684898

RESUMO

Health equity is the state in which everyone has fair and just opportunities to attain their highest level of health. The field of human genomics has fallen short in increasing health equity, largely because the diversity of the human population has been inadequately reflected among participants of genomics research. This lack of diversity leads to disparities that can have scientific and clinical consequences. Achieving health equity related to genomics will require greater effort in addressing inequities within the field. As part of the commitment of the National Human Genome Research Institute (NHGRI) to advancing health equity, it convened experts in genomics and health equity research to make recommendations and performed a review of current literature to identify the landscape of gaps and opportunities at the interface between human genomics and health equity research. This Perspective describes these findings and examines health equity within the context of human genomics and genomic medicine.


Assuntos
Genômica , Equidade em Saúde , Humanos , Genômica/métodos , Estados Unidos , Genoma Humano , National Human Genome Research Institute (U.S.)
9.
J Infect Dis ; 205(7): 1155-62, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22362864

RESUMO

BACKGROUND: To date, only mutations in CCR5 have been shown to confer resistance to human immunodeficiency virus type 1 (HIV-1) infection, and these explain only a small fraction of the observed variability in HIV susceptibility. METHODS: We performed a meta-analysis between 2 independent European genomewide association studies, each comparing HIV-1 seropositive cases with normal population controls known to be HIV uninfected, to identify single-nucleotide polymorphisms (SNPs) associated with the HIV-1 acquisition phenotype. SNPs exhibiting P < 10(-5) in this first stage underwent second-stage analysis in 2 independent US cohorts of European descent. RESULTS: After the first stage, a single highly significant association was revealed for the chromosome 8 rs6996198 with HIV-1 acquisition and was replicated in both second-stage cohorts. Across the 4 groups, the rs6996198-T allele was consistently associated with a significant reduced risk of HIV-1 infection, and the global meta-analysis reached genomewide significance: P(combined) = 7.76 × 10(-8). CONCLUSIONS: We provide strong evidence of association for a common variant with HIV-1 acquisition in populations of European ancestry. This protective signal against HIV-1 infection is the first identified outside the CCR5 nexus. First clues point to a potential functional role for a nearby candidate gene, CYP7B1, but this locus warrants further investigation.


Assuntos
Resistência à Doença , Infecções por HIV/genética , Infecções por HIV/imunologia , HIV-1/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Família 7 do Citocromo P450 , Europa (Continente) , Feminino , Frequência do Gene , Estudos de Associação Genética , Loci Gênicos , Infecções por HIV/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Esteroide Hidroxilases/genética , Estados Unidos
10.
Mol Ecol ; 21(7): 1617-31, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22335296

RESUMO

Urbanization can result in the fragmentation of once contiguous natural landscapes into a patchy habitat interspersed within a growing urban matrix. Animals living in fragmented landscapes often have reduced movement among habitat patches because of avoidance of intervening human development, which potentially leads to both reduced gene flow and pathogen transmission between patches. Mammalian carnivores with large home ranges, such as bobcats (Lynx rufus), may be particularly sensitive to habitat fragmentation. We performed genetic analyses on bobcats and their directly transmitted viral pathogen, feline immunodeficiency virus (FIV), to investigate the effects of urbanization on bobcat movement. We predicted that urban development, including major freeways, would limit bobcat movement and result in genetically structured host and pathogen populations. We analysed molecular markers from 106 bobcats and 19 FIV isolates from seropositive animals in urban southern California. Our findings indicate that reduced gene flow between two primary habitat patches has resulted in genetically distinct bobcat subpopulations separated by urban development including a major highway. However, the distribution of genetic diversity among FIV isolates determined through phylogenetic analyses indicates that pathogen genotypes are less spatially structured-exhibiting a more even distribution between habitat fragments. We conclude that the types of movement and contact sufficient for disease transmission occur with enough frequency to preclude structuring among the viral population, but that the bobcat population is structured owing to low levels of effective bobcat migration resulting in gene flow. We illustrate the utility in using multiple molecular markers that differentially detect movement and gene flow between subpopulations when assessing connectivity.


Assuntos
Ecossistema , Síndrome de Imunodeficiência Adquirida Felina/transmissão , Fluxo Gênico , Lynx/genética , Lynx/virologia , Alelos , Animais , Teorema de Bayes , California , Gatos , Análise por Conglomerados , Variação Genética , Genética Populacional/métodos , Técnicas de Genotipagem , Vírus da Imunodeficiência Felina/genética , Funções Verossimilhança , Repetições de Microssatélites , Filogenia , Urbanização
11.
J Infect Dis ; 203(10): 1491-502, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21502085

RESUMO

BACKGROUND: Host genetic variation influences human immunodeficiency virus (HIV) infection and progression to AIDS. Here we used clinically well-characterized subjects from 5 pretreatment HIV/AIDS cohorts for a genome-wide association study to identify gene associations with rate of AIDS progression. METHODS: European American HIV seroconverters (n = 755) were interrogated for single-nucleotide polymorphisms (SNPs) (n = 700,022) associated with progression to AIDS 1987 (Cox proportional hazards regression analysis, co-dominant model). RESULTS: Association with slower progression was observed for SNPs in the gene PARD3B. One of these, rs11884476, reached genome-wide significance (relative hazard = 0.3; P =3. 370 × 10(-9)) after statistical correction for 700,022 SNPs and contributes 4.52% of the overall variance in AIDS progression in this study. Nine of the top-ranked SNPs define a PARD3B haplotype that also displays significant association with progression to AIDS (hazard ratio, 0.3; P = 3.220 × 10(-8)). One of these SNPs, rs10185378, is a predicted exonic splicing enhancer; significant alteration in the expression profile of PARD3B splicing transcripts was observed in B cell lines with alternate rs10185378 genotypes. This SNP was typed in European cohorts of rapid progressors and was found to be protective for AIDS 1993 definition (odds ratio, 0.43, P = .025). CONCLUSIONS: These observations suggest a potential unsuspected pathway of host genetic influence on the dynamics of AIDS progression.


Assuntos
Síndrome da Imunodeficiência Adquirida/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Regulação da Expressão Gênica/imunologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Polimorfismo de Nucleotídeo Único , Síndrome da Imunodeficiência Adquirida/patologia , Mapeamento Cromossômico , Progressão da Doença , Genoma Humano , Humanos
12.
J Mol Evol ; 72(2): 222-31, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21188366

RESUMO

The highly polymorphic CYP2D6 protein metabolizes about 25% of commonly used drugs and underlies a broad spectrum of drug responses among individuals. In contrast to extensive knowledge on the human CYP2D6 gene, little is known about the gene in non-human mammals. CYP2D6 mRNA from 23 cats (Felidae) spanning seven species were compared to available CYPD6 sequences in ten additional mammals and multiple allelic variants in humans. A relatively high mean dN/dS ratio (0.565) was observed, especially within Felidae. Pairwise dN/dS ratios were non-monotonically distributed with respect to evolutionary distance suggesting either positive selection or retention of slightly deleterious mutations. Positive selection on specific codons, most notably in regions involved in substrate recognition and membrane anchoring is supported and the possible influence of diet on specific amino acid changes in substrate binding sites is discussed.


Assuntos
Citocromo P-450 CYP2D6/genética , Felidae/genética , Sequência de Aminoácidos , Aminoácidos/química , Animais , Teorema de Bayes , Gatos , Evolução Molecular , Variação Genética , Humanos , Mutação INDEL , Funções Verossimilhança , Modelos Genéticos , Mutação de Sentido Incorreto , NADH Desidrogenase/genética , Proteínas Nucleares/genética , Mutação Puntual , Estrutura Secundária de Proteína , Análise de Sequência de DNA
13.
Crit Care Med ; 39(6): 1306-12, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21336115

RESUMO

OBJECTIVES: Guidelines recommend that sepsis be treated with an early resuscitation protocol such as early goal-directed therapy. Our objective was to assess the cost-effectiveness of implementing early goal-directed therapy as a routine protocol. DESIGN: Prospective before and after study. SETTING: Large urban hospital emergency department with >110,000 visits/yr. PATIENTS: The target population was patients with consensus criteria for septic shock. We excluded those with age <18 yrs, no aggressive care desired, or need for immediate surgery. INTERVENTIONS: Clinical and cost data were prospectively collected on two groups: 1) patients from 1 yr before; and 2) 2 yrs after implementing early goal-directed therapy as standard of care. Before phase patients received nonprotocolized care at attending discretion. The primary outcomes were 1-yr mortality, discounted life expectancy, and quality-adjusted life-years. Using costs and quality-adjusted life-years, we constructed an incremental cost-effectiveness ratio and performed a net monetary benefit analysis, producing the probability that the intervention was cost-effective given different values for the willingness to pay for a quality-adjusted life-year. RESULTS: Two hundred eighty-five subjects, 79 in the before and 206 in the after phases, were enrolled. Treatment with early goal-directed therapy was associated with an increased hospital cost of $7,028 and an increase in both discounted sepsis-adjusted life expectancy and quality-adjusted life years of 1.5 and 1.3 yrs, respectively. Early goal-directed therapy use was associated with a cost of $5,397 per quality-adjusted life-years gained and the net monetary benefit analysis indicates a 98% probability (p = .038) that early goal-directed therapy is cost-effective at a willingness to pay of $50,000 per quality-adjusted life-years. CONCLUSION: Implementation of early goal-directed therapy in the emergency department care of patients with severe sepsis is cost-effective.


Assuntos
Serviço Hospitalar de Emergência/economia , Ressuscitação/economia , Sepse/terapia , Padrão de Cuidado/economia , Adulto , Idoso , Protocolos Clínicos , Estudos de Coortes , Análise Custo-Benefício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anos de Vida Ajustados por Qualidade de Vida , Estudos Retrospectivos , Sepse/diagnóstico , Sepse/mortalidade , Taxa de Sobrevida , Resultado do Tratamento
14.
PLoS Genet ; 4(11): e1000251, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18989457

RESUMO

The lion Panthera leo is one of the world's most charismatic carnivores and is one of Africa's key predators. Here, we used a large dataset from 357 lions comprehending 1.13 megabases of sequence data and genotypes from 22 microsatellite loci to characterize its recent evolutionary history. Patterns of molecular genetic variation in multiple maternal (mtDNA), paternal (Y-chromosome), and biparental nuclear (nDNA) genetic markers were compared with patterns of sequence and subtype variation of the lion feline immunodeficiency virus (FIV(Ple)), a lentivirus analogous to human immunodeficiency virus (HIV). In spite of the ability of lions to disperse long distances, patterns of lion genetic diversity suggest substantial population subdivision (mtDNA Phi(ST) = 0.92; nDNA F(ST) = 0.18), and reduced gene flow, which, along with large differences in sero-prevalence of six distinct FIV(Ple) subtypes among lion populations, refute the hypothesis that African lions consist of a single panmictic population. Our results suggest that extant lion populations derive from several Pleistocene refugia in East and Southern Africa ( approximately 324,000-169,000 years ago), which expanded during the Late Pleistocene ( approximately 100,000 years ago) into Central and North Africa and into Asia. During the Pleistocene/Holocene transition ( approximately 14,000-7,000 years), another expansion occurred from southern refugia northwards towards East Africa, causing population interbreeding. In particular, lion and FIV(Ple) variation affirms that the large, well-studied lion population occupying the greater Serengeti Ecosystem is derived from three distinct populations that admixed recently.


Assuntos
Evolução Molecular , Genômica , Vírus da Imunodeficiência Felina/genética , Leões/genética , Leões/virologia , África , Migração Animal , Animais , Ásia , DNA Mitocondrial/genética , DNA Viral/genética , Variação Genética , Interações Hospedeiro-Patógeno , Vírus da Imunodeficiência Felina/classificação , Leões/classificação , Repetições de Microssatélites , Dados de Sequência Molecular , Filogenia , População/genética
15.
J Infect Dis ; 202(4): 606-13, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20617924

RESUMO

BACKGROUND: Cytomegalovirus (CMV) retinitis is a common opportunistic infection among patients with AIDS and still causes visual morbidity despite the wide spread usage of highly active antiretroviral therapy (HAART). The ubiquitous CMV pathogen contains a human interleukin-10 (IL-10) homolog in its genome and utilizes it to evade host immune reactions through an IL-10 receptor mediated immune-suppression pathway. METHODS: Effects of IL-10R1, IL-10 and previously described AIDS restriction gene variants are investigated on the development of CMV retinitis in the Longitudinal Study of the Ocular Complications of AIDS (LSOCA) cohort (N = 1284). RESULTS: In European Americans (n = 750), a haplotype carrying an amino acid changing variation in the cytoplasmic domain (S420L) of IL-10R1 can be protective (OR, 0.14; 95% CI, 0.02-0.94; P = .04) against, whereas another haplotype carrying an amino acid changing variation in the extracellular domain (I224V) of IL-10R1 can be more susceptible (OR, 6.21; 95% CI, 1.22- 31.54; P = .03) to CMV retinitis. In African Americans (n = 534), potential effects of IL-10 variants are observed. CONCLUSION: Host genetics may have a role in the occurrence of CMV retinitis in patients infected with HIV.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/genética , Infecções Oportunistas Relacionadas com a AIDS/imunologia , Síndrome da Imunodeficiência Adquirida/complicações , Retinite por Citomegalovirus/genética , Predisposição Genética para Doença , Imunidade Inata , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Adulto , Negro ou Afro-Americano , Retinite por Citomegalovirus/epidemiologia , Feminino , Frequência do Gene , Humanos , Interleucina-10/genética , Subunidade alfa de Receptor de Interleucina-10/genética , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Estados Unidos , População Branca
16.
J Infect Dis ; 202(12): 1836-45, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21083371

RESUMO

BACKGROUND: High-throughput genome-wide techniques have facilitated the identification of previously unknown host proteins involved in cellular human immunodeficiency virus (HIV) infection. Recently, 3 independent studies have used small interfering RNA technology to silence each gene in the human genome to determine the importance of each in HIV infection. Genes conferring a significant effect were termed HIV-dependency factors (HDFs). METHODS: We assembled high-density panels of 6380 single-nucleotide polymorphisms (SNPs) in 278 HDF genes and tested for genotype associations with HIV infection and AIDS progression in 1633 individuals from clinical AIDS cohorts. RESULTS: After statistical correction for multiple tests, significant associations with HIV acquisition were found for SNPs in 2 genes, NCOR2 and IDH1. Weaker associations with AIDS progression were revealed for SNPs within the TM9SF2 and EGFR genes. CONCLUSIONS: This study independently verifies the influence of NCOR2 and IDH1 on HIV transmission, and its findings suggest that variation in these genes affects susceptibility to HIV infection in exposed individuals.


Assuntos
Suscetibilidade a Doenças , Infecções por HIV/genética , Infecções por HIV/transmissão , HIV-1/patogenicidade , Interações Hospedeiro-Patógeno , Isocitrato Desidrogenase/genética , Correpressor 2 de Receptor Nuclear/genética , Progressão da Doença , Receptores ErbB/genética , Frequência do Gene , Humanos , Masculino , Proteínas de Membrana/genética , Polimorfismo de Nucleotídeo Único
17.
J Infect Dis ; 201(4): 618-26, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20064070

RESUMO

BACKGROUND: A mean of 9-10 years of human immunodeficiency virus type 1 (HIV-1) infection elapse before clinical AIDS develops in untreated persons, but this rate of disease progression varies substantially among individuals. To investigate host genetic determinants of the rate of progression to clinical AIDS, we performed a multistage genomewide association study. METHODS: The discovery stage comprised 156 individuals from the Multicenter AIDS Cohort Study, enriched with rapid and long-term nonprogressors to increase statistical power. This was followed by replication tests of putatively associated genotypes in an independent population of 590 HIV-1-infected seroconverters. RESULTS: Significant associations with delayed AIDS progression were observed in a haplotype located at 1q41, 36 kb upstream of PROX1 on chromosome 1 (relative hazard ratio, 0.69; Fisher's combined P = 6.23 X 10(-7)). This association was replicated further in an analysis stratified by transmission mode, with the effect consistent in sexual or mucosal and parenteral transmission (relative hazard ratios, 0.72 and 0.63, respectively; combined P = 1.63 X 10(-6)). CONCLUSIONS: This study identified and replicated a locus upstream of PROX1 that is associated with delayed progression to clinical AIDS. PROX1 is a negative regulator of interferon-gamma expression in T cells and also mitigates the advancement of vascular neoplasms, such as Kaposi sarcoma, a common AIDS-defining malignancy. This study adds to the cumulative polygenic host component that effectively regulates the progression to clinical AIDS among HIV-1-infected individuals, raising prospects for potential new avenues for therapy and improvements in AIDS prognosis.


Assuntos
Síndrome da Imunodeficiência Adquirida/genética , Cromossomos Humanos Par 1 , Estudo de Associação Genômica Ampla/métodos , Infecções por HIV/genética , HIV-1 , Proteínas de Homeodomínio/genética , Proteínas Supressoras de Tumor/genética , Síndrome da Imunodeficiência Adquirida/patologia , Adulto , Estudos de Coortes , Progressão da Doença , Loci Gênicos , Predisposição Genética para Doença , Infecções por HIV/patologia , Humanos , Desequilíbrio de Ligação , Modelos Logísticos , Masculino , Polimorfismo de Nucleotídeo Único , Modelos de Riscos Proporcionais , Carga Viral
18.
Tenn Med ; 104(10): 35-8, 45, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22165470

RESUMO

BACKGROUND: Potentially avoidable hospitalizations are inpatient admissions for certain conditions, called Ambulatory Care Sensitive Conditions (ACSCs), which can potentially be prevented by effective outpatient treatment of individuals who actively participate in their own care and engage in responsible personal behavior. Changes in the rates of ACSC hospitalizations over time may signal an improvement or deterioration in the quality and effectiveness of ambulatory care. These long-term trends may also suggest changes in the underlying factors such as lifestyle choices and dietary practices of individuals and families. OBJECTIVE: This study presents data from the Tennessee Hospital Discharge Datasets on changes in ACSC hospitalizations as a percent of all hospitalizations for 1998-2006. METHODS: Retrospective analysis of administrative data based on the UB-92 claims forms submitted by all short-term acute-care hospitals in Tennessee. RESULTS: Total ACSC hospitalizations in Tennessee increased by 4.2 percent between 1998 and 2006, while the total costs for ACSC hospitalizations decreased by 1.8 percent in constant 2006 dollars. In comparison, total admissions for all conditions increased by 15 percent during 1998-2006 while total hospital costs for all conditions increased by 21 percent. The rate of increase in ACSC hospitalization varied according to patient's race, insurance type, and whether the patient's health plan is managed care or fee-for-service. ACSC patients admitted through an emergency department outnumbered their counterparts who were not admitted through an emergency department by a factor of more than two throughout 1998-2006. CONCLUSIONS: Our analysis of long-term trends of ACSC hospitalizations in Tennessee reveals a mixed bag of good news and bad news. In 1998-2006, ACSC hospitalizations rose at a much lower rate than overall hospitalizations for all conditions. Meanwhile, the costs of ACSC hospitalization in 2006 constant dollars decreased while the costs of overall hospitalizations increased. Minority groups such as blacks and patients insured under TennCare did not experience much decline in ACSC hospitalizations, especially in the rates of chronic ambulatory-care sensitive conditions, when compared with their white and commercially-insured counterparts. Patients whose care was managed experienced smaller declines in ACSC hospitalizations than those not under managed care. Finally, the number of ACSC hospitalizations admitted through an ED outnumbered those admitted through the regular hospital admission department during the study period, and the gap between the two sources of admissions grew larger over time.


Assuntos
Assistência Ambulatorial/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Prevenção de Acidentes , Doença Aguda , Adulto , Assistência Ambulatorial/legislação & jurisprudência , Assistência Ambulatorial/normas , Doença Crônica , Hospitalização/economia , Hospitalização/legislação & jurisprudência , Humanos , Estilo de Vida , Indicadores de Qualidade em Assistência à Saúde , Tennessee
19.
BMC Genomics ; 11: 724, 2010 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-21176216

RESUMO

BACKGROUND: As we enter an era when testing millions of SNPs in a single gene association study will become the standard, consideration of multiple comparisons is an essential part of determining statistical significance. Bonferroni adjustments can be made but are conservative due to the preponderance of linkage disequilibrium (LD) between genetic markers, and permutation testing is not always a viable option. Three major classes of corrections have been proposed to correct the dependent nature of genetic data in Bonferroni adjustments: permutation testing and related alternatives, principal components analysis (PCA), and analysis of blocks of LD across the genome. We consider seven implementations of these commonly used methods using data from 1514 European American participants genotyped for 700,078 SNPs in a GWAS for AIDS. RESULTS: A Bonferroni correction using the number of LD blocks found by the three algorithms implemented by Haploview resulted in an insufficiently conservative threshold, corresponding to a genome-wide significance level of α = 0.15 - 0.20. We observed a moderate increase in power when using PRESTO, SLIDE, and simpleℳ when compared with traditional Bonferroni methods for population data genotyped on the Affymetrix 6.0 platform in European Americans (α = 0.05 thresholds between 1 × 10(-7) and 7 × 10(-8)). CONCLUSIONS: Correcting for the number of LD blocks resulted in an anti-conservative Bonferroni adjustment. SLIDE and simpleℳ are particularly useful when using a statistical test not handled in optimized permutation testing packages, and genome-wide corrected p-values using SLIDE, are much easier to interpret for consumers of GWAS studies.


Assuntos
Estudo de Associação Genômica Ampla/métodos , Estudos de Casos e Controles , Bases de Dados Genéticas , Haplótipos/genética , Humanos , Desequilíbrio de Ligação/genética , Análise de Componente Principal , Fatores de Tempo
20.
J Hum Genet ; 55(9): 613-20, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20574427

RESUMO

We attempted to refine the understanding of an association of Y-chromosomal haplogroup I (hg-I) with enhanced AIDS progression that had been previously reported. First, we compared the progression phenotype between hg-I and its phylogenetically closest haplogroup J. Then, we took a candidate gene approach resequencing DDX3Y, a crucial autoimmunity gene, in hg-I and other common European Y-chromosome haplogroups looking for functional variants. We extended the genetic analyses to CD24L4 and compared and contrasted the roles of disease-based selection, demographic history and population structure shaping the contemporary genetic landscape of hg-I chromosomes. Our results confirmed and refined the AIDS progression signal to hg-I, though no gene variant was identified that can explain the disease association. Molecular evolutionary and genetic analyses of the examined loci suggested a unique evolutionary history in hg-I, probably shaped by complex interactions of selection, demographic history and high geographical differentiation leading to the formation of distinct hg-I subhaplogroups that today are associated with HIV/AIDS onset. Clearly, further studies on Y-chromosome candidate loci sequencing to discover functional variants and discern the roles of evolutionary factors are warranted.


Assuntos
Síndrome da Imunodeficiência Adquirida/genética , Cromossomos Humanos Y , RNA Helicases DEAD-box/genética , Haplótipos , Polimorfismo de Nucleotídeo Único , Alelos , Antígeno CD24/genética , Progressão da Doença , Variação Genética , Genética Populacional , Humanos , Masculino , Antígenos de Histocompatibilidade Menor , Filogenia , População Branca/genética
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa