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1.
Mol Cell ; 59(6): 956-69, 2015 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-26365382

RESUMO

Endosomal protein recycling is a fundamental cellular process important for cellular homeostasis, signaling, and fate determination that is implicated in several diseases. WASH is an actin-nucleating protein essential for this process, and its activity is controlled through K63-linked ubiquitination by the MAGE-L2-TRIM27 ubiquitin ligase. Here, we show that the USP7 deubiquitinating enzyme is an integral component of the MAGE-L2-TRIM27 ligase and is essential for WASH-mediated endosomal actin assembly and protein recycling. Mechanistically, USP7 acts as a molecular rheostat to precisely fine-tune endosomal F-actin levels by counteracting TRIM27 auto-ubiquitination/degradation and preventing overactivation of WASH through directly deubiquitinating it. Importantly, we identify de novo heterozygous loss-of-function mutations of USP7 in individuals with a neurodevelopmental disorder, featuring intellectual disability and autism spectrum disorder. These results provide unanticipated insights into endosomal trafficking, illuminate the cooperativity between an ubiquitin ligase and a deubiquitinating enzyme, and establish a role for USP7 in human neurodevelopmental disease.


Assuntos
Transtorno do Espectro Autista/enzimologia , Endossomos/metabolismo , Deficiência Intelectual/enzimologia , Proteínas dos Microfilamentos/metabolismo , Ubiquitina Tiolesterase/fisiologia , Adolescente , Transtorno do Espectro Autista/genética , Criança , Pré-Escolar , Proteínas de Ligação a DNA/metabolismo , Retroalimentação Fisiológica , Feminino , Células HCT116 , Haploinsuficiência , Humanos , Hipotálamo/metabolismo , Deficiência Intelectual/genética , Masculino , Neurônios/enzimologia , Proteínas Nucleares/metabolismo , Transporte Proteico , Proteólise , Deleção de Sequência , Peptidase 7 Específica de Ubiquitina , Ubiquitinação
2.
Dev Dyn ; 251(3): 424-443, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34350653

RESUMO

The ductus arteriosus (DA) is a unique fetal vascular shunt, which allows blood to bypass the developing lungs in utero. After birth, changes in complex signaling pathways lead to constriction and permanent closure of the DA. The persistent patency of the DA (PDA) is a common disorder in preterm infants, yet the underlying causes of PDA are not fully defined. Although limits on the availability of human DA tissues prevent comprehensive studies on the mechanisms of DA function, mouse models have been developed that reveal critical pathways in DA regulation. Over 20 different transgenic models of PDA in mice have been described, with implications for human DA biology. Similarly, we enumerate 224 human single-gene syndromes that are associated with PDA, including a small subset that consistently feature PDA as a prominent phenotype. Comparison and functional analyses of these genes provide insight into DA development and identify key regulatory pathways that may serve as potential therapeutic targets for the management of PDA.


Assuntos
Permeabilidade do Canal Arterial , Canal Arterial , Animais , Modelos Animais de Doenças , Canal Arterial/metabolismo , Permeabilidade do Canal Arterial/tratamento farmacológico , Permeabilidade do Canal Arterial/etiologia , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Camundongos
3.
Liver Transpl ; 27(12): 1799-1810, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34058057

RESUMO

Liver transplantation (LT) for children with urea cycle disorders (UCDs) is capable of correcting the enzymatic defect and preventing progressive neurologic injury. We describe the characteristics and outcomes of pediatric LT recipients with UCDs. We identified all pediatric (<18 years) LT candidates with UCDs in the United Network for Organ Sharing (UNOS) database (February 2002 to September 2020). Multivariable Cox and logistic regression were used to determine risk factors for graft loss and cognitive delay, respectively. Of 424 patients, 1.9% (8/424) experienced waitlist mortality and 95.0% underwent LT (403/424). The most frequently encountered UCDs in our cohort were ornithine transcarbamylase deficiency (46.2%), citrullinemia (20.3%), and argininosuccinic aciduria (ASA; 12.9%). The 1-, 3-, and 5-year graft survival rates were 90.4%, 86.3%, and 85.2%, respectively. Multivariable analysis showed a decreased risk of graft loss with increasing weight at LT (adjusted hazard ratio [aHR], 0.96; 95% confidence interval [CI], 0.94-0.99; P = 0.02), male sex (aHR, 0.49; 95% CI, 0.28-0.85; P = 0.01), and ASA diagnosis (aHR, 0.29; 95% CI, 0.09-0.98; P = 0.047), when adjusting for location (intensive care/hospital/home) and graft type (both P ≥ 0.65). In multivariable logistic regression, waitlist time (adjusted odds ratio [aOR], 1.10; 95% CI, 1.02-1.17; P = 0.009) and male sex (aOR, 1.71; 95% CI, 1.02-2.88; P = 0.04) were associated with increased odds of long-term cognitive delay. Waitlist duration is associated with a long-term risk of cognitive delay. Given excellent long-term outcomes, early LT evaluation should be considered in all children with UCDs to prevent progressive neurologic injury and optimize cognitive outcomes.


Assuntos
Transplante de Fígado , Distúrbios Congênitos do Ciclo da Ureia , Criança , Sobrevivência de Enxerto , Humanos , Transplante de Fígado/efeitos adversos , Masculino , Fatores de Risco , Distúrbios Congênitos do Ciclo da Ureia/complicações , Distúrbios Congênitos do Ciclo da Ureia/diagnóstico , Distúrbios Congênitos do Ciclo da Ureia/epidemiologia , Listas de Espera
4.
Am J Hum Genet ; 100(5): 737-750, 2017 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-28457472

RESUMO

Keratolytic winter erythema (KWE) is a rare autosomal-dominant skin disorder characterized by recurrent episodes of palmoplantar erythema and epidermal peeling. KWE was previously mapped to 8p23.1-p22 (KWE critical region) in South African families. Using targeted resequencing of the KWE critical region in five South African families and SNP array and whole-genome sequencing in two Norwegian families, we identified two overlapping tandem duplications of 7.67 kb (South Africans) and 15.93 kb (Norwegians). The duplications segregated with the disease and were located upstream of CTSB, a gene encoding cathepsin B, a cysteine protease involved in keratinocyte homeostasis. Included in the 2.62 kb overlapping region of these duplications is an enhancer element that is active in epidermal keratinocytes. The activity of this enhancer correlated with CTSB expression in normal differentiating keratinocytes and other cell lines, but not with FDFT1 or NEIL2 expression. Gene expression (qPCR) analysis and immunohistochemistry of the palmar epidermis demonstrated significantly increased expression of CTSB, as well as stronger staining of cathepsin B in the stratum granulosum of affected individuals than in that of control individuals. Analysis of higher-order chromatin structure data and RNA polymerase II ChIA-PET data from MCF-7 cells did not suggest remote effects of the enhancer. In conclusion, KWE in South African and Norwegian families is caused by tandem duplications in a non-coding genomic region containing an active enhancer element for CTSB, resulting in upregulation of this gene in affected individuals.


Assuntos
Catepsina B/metabolismo , Elementos Facilitadores Genéticos , Eritema/genética , Duplicação Gênica , Regulação da Expressão Gênica , Ceratose/genética , Dermatopatias Genéticas/genética , Estudos de Casos e Controles , Catepsina B/genética , Mapeamento Cromossômico , Cromossomos Humanos Par 8/genética , Variações do Número de Cópias de DNA , DNA Glicosilases/genética , DNA Glicosilases/metabolismo , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Epiderme/metabolismo , Epigenômica , Eritema/epidemiologia , Feminino , Marcadores Genéticos , Humanos , Queratinócitos/metabolismo , Ceratose/epidemiologia , Células MCF-7 , Masculino , Noruega/epidemiologia , Linhagem , Dermatopatias Genéticas/epidemiologia , África do Sul/epidemiologia
5.
Genet Med ; 21(8): 1797-1807, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30679821

RESUMO

PURPOSE: Haploinsufficiency of USP7, located at chromosome 16p13.2, has recently been reported in seven individuals with neurodevelopmental phenotypes, including developmental delay/intellectual disability (DD/ID), autism spectrum disorder (ASD), seizures, and hypogonadism. Further, USP7 was identified to critically incorporate into the MAGEL2-USP7-TRIM27 (MUST), such that pathogenic variants in USP7 lead to altered endosomal F-actin polymerization and dysregulated protein recycling. METHODS: We report 16 newly identified individuals with heterozygous USP7 variants, identified by genome or exome sequencing or by chromosome microarray analysis. Clinical features were evaluated by review of medical records. Additional clinical information was obtained on the seven previously reported individuals to fully elucidate the phenotypic expression associated with USP7 haploinsufficiency. RESULTS: The clinical manifestations of these 23 individuals suggest a syndrome characterized by DD/ID, hypotonia, eye anomalies,feeding difficulties, GERD, behavioral anomalies, and ASD, and more specific phenotypes of speech delays including a nonverbal phenotype and abnormal brain magnetic resonance image findings including white matter changes based on neuroradiologic examination. CONCLUSION: The consistency of clinical features among all individuals presented regardless of de novo USP7 variant type supports haploinsufficiency as a mechanism for pathogenesis and refines the clinical impact faced by affected individuals and caregivers.


Assuntos
Deficiência Intelectual/genética , Transtornos do Desenvolvimento da Linguagem/genética , Transtornos do Neurodesenvolvimento/genética , Comportamento Problema , Adolescente , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/fisiopatologia , Criança , Pré-Escolar , Deleção Cromossômica , Proteínas de Ligação a DNA/genética , Genoma Humano/genética , Haploinsuficiência/genética , Humanos , Lactente , Recém-Nascido , Deficiência Intelectual/fisiopatologia , Transtornos do Desenvolvimento da Linguagem/fisiopatologia , Transtornos do Neurodesenvolvimento/fisiopatologia , Proteínas Nucleares/genética , Fenótipo , Proteínas/genética , Sequenciamento do Exoma
6.
Am J Hum Genet ; 93(2): 197-210, 2013 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-23810381

RESUMO

White matter hyperintensities (WMHs) of the brain are important markers of aging and small-vessel disease. WMHs are rare in healthy children and, when observed, often occur with comorbid neuroinflammatory or vasculitic processes. Here, we describe a complex 4 kb deletion in 2q36.3 that segregates with early childhood communication disorders and WMH in 15 unrelated families predominantly from Southeast Asia. The premature brain aging phenotype with punctate and multifocal WMHs was observed in ~70% of young carrier parents who underwent brain MRI. The complex deletion removes the penultimate exon 3 of TM4SF20, a gene encoding a transmembrane protein of unknown function. Minigene analysis showed that the resultant net loss of an exon introduces a premature stop codon, which, in turn, leads to the generation of a stable protein that fails to target to the plasma membrane and accumulates in the cytoplasm. Finally, we report this deletion to be enriched in individuals of Vietnamese Kinh descent, with an allele frequency of about 1%, embedded in an ancestral haplotype. Our data point to a constellation of early language delay and WMH phenotypes, driven by a likely toxic mechanism of TM4SF20 truncation, and highlight the importance of understanding and managing population-specific low-frequency pathogenic alleles.


Assuntos
Senilidade Prematura/genética , Sequência de Bases , Predisposição Genética para Doença , Transtornos do Desenvolvimento da Linguagem/genética , Leucoencefalopatias/genética , Deleção de Sequência , Tetraspaninas/genética , Idade de Início , Senilidade Prematura/complicações , Senilidade Prematura/etnologia , Senilidade Prematura/patologia , Povo Asiático , Encéfalo/metabolismo , Encéfalo/patologia , Criança , Pré-Escolar , Cromossomos Humanos Par 2 , Éxons , Feminino , Humanos , Transtornos do Desenvolvimento da Linguagem/complicações , Transtornos do Desenvolvimento da Linguagem/etnologia , Transtornos do Desenvolvimento da Linguagem/patologia , Leucoencefalopatias/complicações , Leucoencefalopatias/etnologia , Leucoencefalopatias/patologia , Imageamento por Ressonância Magnética , Masculino , Dados de Sequência Molecular , Linhagem , Análise de Sequência de DNA
7.
J Med Genet ; 52(2): 85-94, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25480986

RESUMO

BACKGROUND: Oliver-McFarlane syndrome is characterised by trichomegaly, congenital hypopituitarism and retinal degeneration with choroidal atrophy. Laurence-Moon syndrome presents similarly, though with progressive spinocerebellar ataxia and spastic paraplegia and without trichomegaly. Both recessively inherited disorders have no known genetic cause. METHODS: Whole-exome sequencing was performed to identify the genetic causes of these disorders. Mutations were functionally validated in zebrafish pnpla6 morphants. Embryonic expression was evaluated via in situ hybridisation in human embryonic sections. Human neurohistopathology was performed to characterise cerebellar degeneration. Enzymatic activities were measured in patient-derived fibroblast cell lines. RESULTS: Eight mutations in six families with Oliver-McFarlane or Laurence-Moon syndrome were identified in the PNPLA6 gene, which encodes neuropathy target esterase (NTE). PNPLA6 expression was found in the developing human eye, pituitary and brain. In zebrafish, the pnpla6 curly-tailed morphant phenotype was fully rescued by wild-type human PNPLA6 mRNA and not by mutation-harbouring mRNAs. NTE enzymatic activity was significantly reduced in fibroblast cells derived from individuals with Oliver-McFarlane syndrome. Intriguingly, adult brain histology from a patient with highly overlapping features of Oliver-McFarlane and Laurence-Moon syndromes revealed extensive cerebellar degeneration and atrophy. CONCLUSIONS: Previously, PNPLA6 mutations have been associated with spastic paraplegia type 39, Gordon-Holmes syndrome and Boucher-Neuhäuser syndromes. Discovery of these additional PNPLA6-opathies further elucidates a spectrum of neurodevelopmental and neurodegenerative disorders associated with NTE impairment and suggests a unifying mechanism with diagnostic and prognostic importance.


Assuntos
Blefaroptose/enzimologia , Blefaroptose/genética , Hidrolases de Éster Carboxílico/genética , Nanismo/enzimologia , Nanismo/genética , Predisposição Genética para Doença , Hipertricose/enzimologia , Hipertricose/genética , Deficiência Intelectual/enzimologia , Deficiência Intelectual/genética , Síndrome de Laurence-Moon/enzimologia , Síndrome de Laurence-Moon/genética , Retinose Pigmentar/enzimologia , Retinose Pigmentar/genética , Alelos , Sequência de Aminoácidos , Animais , Hidrolases de Éster Carboxílico/química , Sistema Nervoso Central/patologia , Deficiências do Desenvolvimento/enzimologia , Deficiências do Desenvolvimento/genética , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Dados de Sequência Molecular , Mutação/genética , Fenótipo , Fosfolipases/química , Fosfolipases/genética , Estrutura Terciária de Proteína , Retina/patologia , Peixe-Zebra/embriologia
8.
N Engl J Med ; 362(20): 1901-8, 2010 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-20445167

RESUMO

Tourette's syndrome is a common developmental neuropsychiatric disorder characterized by chronic motor and vocal tics. Despite a strong genetic contribution, inheritance is complex, and risk alleles have proven difficult to identify. Here, we describe an analysis of linkage in a two-generation pedigree leading to the identification of a rare functional mutation in the HDC gene encoding L-histidine decarboxylase, the rate-limiting enzyme in histamine biosynthesis. Our findings, together with previously published data from model systems, point to a role for histaminergic neurotransmission in the mechanism and modulation of Tourette's syndrome and tics.


Assuntos
Códon sem Sentido , Histidina Descarboxilase/genética , Síndrome de Tourette/genética , Mapeamento Cromossômico , Feminino , Genes Dominantes , Ligação Genética , Predisposição Genética para Doença , Haplótipos , Histidina Descarboxilase/metabolismo , Humanos , Masculino , Repetições de Microssatélites , Linhagem , Reação em Cadeia da Polimerase
9.
Pediatr Cardiol ; 33(7): 1175-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22434508

RESUMO

Sinus tachycardia is common in cases of Duchenne muscular dystrophy (DMD). The authors hypothesized that an elevated heart rate would herald cardiomyopathy onset. A retrospective case-control study was performed with 55 DMD boys and 150 age-matched control boys. The variables were age, heart rate, shortening fraction, and left ventricular end-diastolic dimension. Cardiomyopathy was defined as a shortening fraction less than 28%. The DMD boys had a higher initial heart rate with no baseline echocardiographic evidence of cardiomyopathy. The control subjects showed a statistically significant age-related decline in heart rate (p = 0.001) but not the DMD boys. Cardiomyopathy developed in 17 of the 55 DMD boys over a period of 4.6 ± 1.6 years. The DMD upper and lower heart rate groups were similar in age, follow-up time, and initial shortening fraction, yet cardiomyopathy developed in 14 (42%) of 33 upper quartile boys but only 3 (14%) of 22 lower quartile DMD boys (odds ratio, 6.5 (95% confidence interval, 1.15-18.92; p < 0.05). Compared with the control subjects, the DMD boys had a higher resting heart rate and a lack of age-related heart rate decline. The DMD boys in the upper heart rate quartile were more likely to progress to cardiomyopathy than those in the lower quartiles. This study establishes heart rate elevation as a statistically significant risk factor for cardiomyopathy. Further studies may define heart rate cutoffs for early pharmacologic intervention for incipient cardiomyopathy.


Assuntos
Cardiomiopatias/fisiopatologia , Frequência Cardíaca/fisiologia , Distrofia Muscular de Duchenne/fisiopatologia , Adolescente , Estudos de Casos e Controles , Criança , Humanos , Masculino , Análise de Regressão , Estudos Retrospectivos
10.
Am J Hum Genet ; 82(1): 165-73, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18179895

RESUMO

Autism spectrum disorders (ASD) are a group of related neurodevelopmental syndromes with complex genetic etiology. We identified a de novo chromosome 7q inversion disrupting Autism susceptibility candidate 2 (AUTS2) and Contactin Associated Protein-Like 2 (CNTNAP2) in a child with cognitive and social delay. We focused our initial analysis on CNTNAP2 based on our demonstration of disruption of Contactin 4 (CNTN4) in a patient with ASD; the recent finding of rare homozygous mutations in CNTNAP2 leading to intractable seizures and autism; and in situ and biochemical analyses reported herein that confirm expression in relevant brain regions and demonstrate the presence of CNTNAP2 in the synaptic plasma membrane fraction of rat forebrain lysates. We comprehensively resequenced CNTNAP2 in 635 patients and 942 controls. Among patients, we identified a total of 27 nonsynonymous changes; 13 were rare and unique to patients and 8 of these were predicted to be deleterious by bioinformatic approaches and/or altered residues conserved across all species. One variant at a highly conserved position, I869T, was inherited by four affected children in three unrelated families, but was not found in 4010 control chromosomes (p = 0.014). Overall, this resequencing data demonstrated a modest nonsignificant increase in the burden of rare variants in cases versus controls. Nonetheless, when viewed in light of two independent studies published in this issue of AJHG showing a relationship between ASD and common CNTNAP2 alleles, the cytogenetic and mutation screening data suggest that rare variants may also contribute to the pathophysiology of ASD, but place limits on the magnitude of this contribution.


Assuntos
Transtorno Autístico/genética , Predisposição Genética para Doença , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Animais , Criança , Feminino , Humanos , Masculino , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , RNA Mensageiro , Ratos , Lobo Temporal/metabolismo
11.
BMC Med Genet ; 12: 92, 2011 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-21740577

RESUMO

BACKGROUND: Although adolescent idiopathic scoliosis affects approximately 3% of adolescents, the genetic contributions have proven difficult to identify. Work in model organisms, including zebrafish, chickens, and mice, has implicated the lysyl oxidase family of enzymes in the development of scoliosis. We hypothesized that common polymorphisms in the five human lysyl oxidase genes (LOX, LOXL1, LOXL2, LOXL3, and LOXL4) may be associated with the phenotype of adolescent idiopathic scoliosis. METHODS: This was a case-control genetic association study. A total of 112 coding and tag SNPs in LOX, LOXL1, LOXL2, LOXL3, and LOXL4 were genotyped in a discovery cohort of 138 cases and 411 controls. Genotypes were tested for association with adolescent idiopathic scoliosis by logistic regression with a two degree of freedom genotypic model and gender as a covariate. Fourteen SNPs with p < 0.1 in the discovery phase were genotyped in an independent replication cohort of 400 cases and 506 controls. RESULTS: No evidence for significant association was found between coding or tag SNPs in LOX, LOXL1, LOXL2, LOXL3, and LOXL4 and the phenotype of adolescent idiopathic scoliosis. CONCLUSIONS: Despite suggestive evidence in model organisms, common variants and known coding SNPs in the five human lysyl oxidase genes do not confer increased genotypic risk for adolescent idiopathic scoliosis. The above methodology does not address rare variants or individually private mutations in these genes, and future research may focus on this area.


Assuntos
Proteína-Lisina 6-Oxidase/genética , Escoliose/genética , Adolescente , Aminoácido Oxirredutases/genética , Estudos de Casos e Controles , Estudos de Coortes , Cobre/metabolismo , Estudos de Associação Genética , Genótipo , Humanos , Modelos Logísticos , Razão de Chances , Fenótipo , Polimorfismo de Nucleotídeo Único
12.
BMC Med Genet ; 12: 127, 2011 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-21957892

RESUMO

BACKGROUND: Genome-wide association studies (GWAS) have identified new candidate genes for the occurrence of acute coronary syndrome (ACS), but possible effects of such genes on survival following ACS have yet to be investigated. METHODS: We examined 95 polymorphisms in 69 distinct gene regions identified in a GWAS for premature myocardial infarction for their association with post-ACS mortality among 811 whites recruited from university-affiliated hospitals in Kansas City, Missouri. We then sought replication of a positive genetic association in a large, racially diverse cohort of myocardial infarction patients (N = 2284) using Kaplan-Meier survival analyses and Cox regression to adjust for relevant covariates. Finally, we investigated the apparent association further in 6086 additional coronary artery disease patients. RESULTS: After Cox adjustment for other ACS risk factors, of 95 SNPs tested in 811 whites only the association with the rs6922269 in MTHFD1L was statistically significant, with a 2.6-fold mortality hazard (P = 0.007). The recessive A/A genotype was of borderline significance in an age- and race-adjusted analysis of the entire combined cohort (N = 3095; P = 0.052), but this finding was not confirmed in independent cohorts (N = 6086). CONCLUSIONS: We found no support for the hypothesis that the GWAS-identified variants in this study substantially alter the probability of post-ACS survival. Large-scale, collaborative, genome-wide studies may be required in order to detect genetic variants that are robustly associated with survival in patients with coronary artery disease.


Assuntos
Síndrome Coronariana Aguda/genética , Variação Genética , Estudo de Associação Genômica Ampla/estatística & dados numéricos , Síndrome Coronariana Aguda/mortalidade , Idoso , Idoso de 80 Anos ou mais , Aminoidrolases/genética , Estudos de Coortes , Feminino , Formiato-Tetra-Hidrofolato Ligase/genética , Genótipo , Humanos , Estimativa de Kaplan-Meier , Masculino , Metilenotetra-Hidrofolato Desidrogenase (NADP)/genética , Pessoa de Meia-Idade , Complexos Multienzimáticos/genética , Infarto do Miocárdio/genética , Infarto do Miocárdio/mortalidade , Polimorfismo de Nucleotídeo Único , Modelos de Riscos Proporcionais , Fatores de Risco , População Branca/genética
13.
Ann Intern Med ; 151(12): 872-7, 2009 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19884615

RESUMO

National Institutes of Health consensus and state-of-the science statements are prepared by independent panels of health professionals and public representatives on the basis of 1) the results of a systematic literature review prepared under contract with the Agency for Healthcare Research and Quality (AHRQ); 2) presentations by investigators working in areas relevant to the conference questions during a 2-day public session; 3) questions and statements from conference attendees during open discussion periods that are part of the public session; and 4) closed deliberations by the panel during the remainder of the second day and morning of the third. This statement is an independent report of the panel and is not a policy statement of the National Institutes of Health or the U.S. government. The statement reflects the panel's assessment of medical knowledge available at the time the statement was written. Thus, it provides a "snapshot in time" of the state of knowledge on the conference topic. When reading the statement, keep in mind that new knowledge is inevitably accumulating through medical research.


Assuntos
Saúde da Família , Nível de Saúde , Anamnese , Atenção Primária à Saúde/métodos , Previsões , Humanos , Anamnese/normas , Avaliação de Resultados em Cuidados de Saúde , Atenção Primária à Saúde/normas , Atenção Primária à Saúde/tendências , Medição de Risco
14.
BMC Med Genet ; 9: 66, 2008 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-18620593

RESUMO

BACKGROUND: Many candidate genes have been reported to be risk factors for acute coronary syndrome (ACS), but their impact on clinical prognosis following ACS is unknown. METHODS: We examined the association of putative genetic risk factors with 3-year post-ACS mortality in 811 ACS survivors at university-affiliated hospitals in Kansas City, Missouri. Through a systematic literature search, we first identified genetic variants reported as susceptibility factors for atherosclerosis or ACS. Restricting our analysis to whites, so as to avoid confounding from racial admixture, we genotyped ACS cases for 89 genetic variants in 72 genes, and performed individual Kaplan-Meier survival analyses. We then performed Cox regression to create multivariate risk prediction models that further minimized potential confounding. RESULTS: Of 89 variants tested, 16 were potentially associated with mortality (P < 0.1 for all), of which 6 were significantly associated (P < 0.05) with mortality following ACS. While these findings are not more than what would be expected by chance (P = 0.28), even after Bonferroni correction and adjustment for traditional cardiac risk factors, the IRS1 972Arg variant association (P = 0.001) retained borderline statistical significance (P < 0.1). CONCLUSION: With the possible exception of IRS1, we conclude that multiple candidate genes were not associated with post-ACS mortality in our patient cohort. Because of power limitations, the 16 gene variants with P values < 0.1 may warrant further study. Our data do not support the hypothesis that the remaining 73 genes have substantial, clinically significant association with mortality after an ACS.


Assuntos
Síndrome Coronariana Aguda/genética , Síndrome Coronariana Aguda/mortalidade , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Missouri/epidemiologia , Fatores de Risco , Análise de Sobrevida , População Branca/genética
16.
JAMA ; 297(14): 1551-61, 2007 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-17426274

RESUMO

CONTEXT: Given the numerous, yet inconsistent, reports of genetic variants being associated with acute coronary syndromes (ACS), there is a need for comprehensive validation of ACS susceptibility genotypes. OBJECTIVE: To perform an extensive validation of putative genetic risk factors for ACS. DESIGN, SETTING, AND PARTICIPANTS: Through a systematic literature search of articles published before March 10, 2005, we identified genetic variants previously reported as significant susceptibility factors for atherosclerosis or ACS. Restricting our analysis to white patients to reduce confounding from racial admixture, we identified 811 patients who presented from March 2001 through June 2003 with ACS at 2 Kansas City, Mo, university-affiliated hospitals. During 2005-2006, we genotyped the 811 patients along with 650 age- and sex-matched controls for 85 variants in 70 genes and attempted to replicate previously reported associations. We further explored possible associations without prior assumption of specific risk models and used the Sign test to search for weak associations. MAIN OUTCOME MEASURES: Compare each prespecified gene variant associated with ACS risk among cases and controls. A surplus of associations would imply that some are associated with ACS. RESULTS: Of 85 variants tested, only 1 putative risk genotype (-455 promoter variant in beta-fibrinogen) was nominally statistically significant (P = .03). Only 4 additional genes were positive in model-free analysis. Neither number of associations was more frequent than expected by chance, given the number of comparisons. Finally, only 41 of 84 predefined risk variants were even marginally more frequent in cases than in controls (with 1 tie), representing a 48.8% "win rate" (95% confidence interval, 38.1%-59.5%) for the collective risk genotypes (P = .91, Sign test). CONCLUSIONS: Our null results provide no support for the hypothesis that any of the 85 genetic variants tested is a susceptibility factor for ACS. These results emphasize the need for robust replication of putative genetic risk factors before their introduction into clinical care.


Assuntos
Angina Instável/genética , Infarto do Miocárdio/genética , Angina Instável/epidemiologia , Aterosclerose/epidemiologia , Aterosclerose/genética , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Método de Monte Carlo , Infarto do Miocárdio/epidemiologia , Reprodutibilidade dos Testes , Fatores de Risco , População Branca
17.
Eur J Hum Genet ; 23(2): 165-72, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24781755

RESUMO

The combination of family-based linkage analysis with high-throughput sequencing is a powerful approach to identifying rare genetic variants that contribute to genetically heterogeneous syndromes. Using parametric multipoint linkage analysis and whole exome sequencing, we have identified a gene responsible for microcephaly (MCP), severe visual impairment, intellectual disability, and short stature through the mapping of a homozygous nonsense alteration in a multiply-affected consanguineous family. This gene, DIAPH1, encodes the mammalian Diaphanous-related formin (mDia1), a member of the diaphanous-related formin family of Rho effector proteins. Upon the activation of GTP-bound Rho, mDia1 generates linear actin filaments in the maintenance of polarity during adhesion, migration, and division in immune cells and neuroepithelial cells, and in driving tangential migration of cortical interneurons in the rodent. Here, we show that patients with a homozygous nonsense DIAPH1 alteration (p.Gln778*) have MCP as well as reduced height and weight. diap1 (mDia1 knockout (KO))-deficient mice have grossly normal body and brain size. However, our histological analysis of diap1 KO mouse coronal brain sections at early and postnatal stages shows unilateral ventricular enlargement, indicating that this mutant mouse shows both important similarities as well as differences with human pathology. We also found that mDia1 protein is expressed in human neuronal precursor cells during mitotic cell division and has a major impact in the regulation of spindle formation and cell division.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas de Transporte/genética , Códon sem Sentido , Homozigoto , Microcefalia/genética , Adolescente , Adulto , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Encéfalo/patologia , Proteínas de Transporte/metabolismo , Linhagem Celular , Criança , Pré-Escolar , Feminino , Forminas , Humanos , Lactente , Masculino , Camundongos , Microcefalia/diagnóstico , Linhagem
18.
Metabolism ; 53(5): 578-82, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15131760

RESUMO

Cigarette smoking impairs glucose tolerance and alters serum levels of hormones involved in glucose metabolism, but the role of nicotine in such hormonal alterations is not well understood. In order to isolate the effects of transdermal nicotine on serum glucose, insulin, growth hormone, and cortisol in smokers, we conducted a randomized double-blind placebo-controlled cross-over study involving 34 healthy volunteer smokers between 18 and 55 years of age. Administration of a 14-mg transdermal nicotine patch resulted in nonsignificantly lowered fasting quantitative insulin-sensitivity index (P =.11) and a nonsignificant 9.3-mg/dL mean increase in serum glucose levels during a 75-g oral glucose tolerance test (OGTT) at time 60 minutes (P =.12). There were no substantial differences between groups in the areas under the curve (AUCs) for glucose (P =.33) or insulin (P =.79) during the OGTT. Levels of insulin and cortisol also were not significantly altered by nicotine. A secondary finding observed in the overall study group (primarily in females) was that nicotine caused a 29% median decrease in serum growth hormone (P =.02). We conclude that nicotine patches may lead to mild hyperglycemia and lowered insulin sensitivity. Further research is needed to determine the clinical implications of the unexpected finding that nicotine decreased growth hormone levels in female smokers.


Assuntos
Glicemia/metabolismo , Hormônio do Crescimento Humano/sangue , Hidrocortisona/sangue , Insulina/sangue , Nicotina/farmacologia , Fumar/sangue , Administração Cutânea , Adolescente , Adulto , Estudos Cross-Over , Método Duplo-Cego , Feminino , Teste de Tolerância a Glucose , Humanos , Masculino , Pessoa de Meia-Idade , Nicotina/administração & dosagem , Nicotina/efeitos adversos , Abandono do Hábito de Fumar
19.
J Natl Med Assoc ; 95(7): 603-14, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12911258

RESUMO

James McCune Smith (1813-1865)--first black American to obtain a medical degree, prominent abolitionist and suffragist, compassionate physician, prolific writer, and public intellectual--has been relatively neglected by historians of medicine. No biography of Smith exists to this day, though he has been the subject of several essays. Born, in his own words, "the son of a self-emancipated bond-woman," and denied admission to colleges in the United States, his native land, Smith earned medical, master's, and baccalaureate degrees at Glasgow University in Scotland. On his return to New York City in 1837, Smith became the first black physician to publish articles in US medical journals. Smith was broadly involved in the anti-slavery and suffrage movements, contributing to and editing abolitionist newspapers and serving as an officer of many organizations for the improvement of social conditions in the black community. In his scientific writings Smith debunked the racial theories in Thomas Jefferson's Notes on the State of Virginia, refuted phrenology and homeopathy, and responded with a forceful statistical critique to the racially biased US Census of 1840. Frederick Douglass, Gerrit Smith, and John Brown personally collaborated with James McCune Smith in the fight for black freedom. As the learned physician-scholar of the abolition movement, Smith was instrumental in making the overthrow of slavery credible and successful.


Assuntos
Negro ou Afro-Americano/história , Direitos Humanos/história , História do Século XX , Humanos , Médicos/história , Problemas Sociais/história , Estados Unidos
20.
Clin Perinatol ; 41(3): 619-32, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25155731

RESUMO

In utero exposure to certain drugs early in pregnancy may adversely affect nephrogenesis. Exposure to drugs later in pregnancy may affect the renin-angiotensin system, which could have an impact on fetal or neonatal renal function. Reduction in nephron number and renal function could have adverse consequences for the child several years later. Data are limited on the information needed to guide decisions for patients and providers regarding the use of certain drugs in pregnancy. The study of drug nephroteratogenicity has not been systematized, a large, standardized, global approach is needed to evaluate the renal risks of in utero drug exposures.


Assuntos
Feto/efeitos dos fármacos , Nefropatias/congênito , Rim/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Teratogênicos , Adolescente , Feminino , Humanos , Recém-Nascido , Rim/embriologia , Gravidez
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