Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
2.
JAMA Netw Open ; 3(10): e2024191, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33026453

RESUMO

Importance: In late December 2019, an outbreak of a novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, China. Data on the routes of transmission to Los Angeles, California, the US West Coast epicenter for coronavirus disease 2019 (COVID-19), and subsequent community spread are limited. Objective: To determine the transmission routes of SARS-CoV-2 to Southern California and elucidate local community spread within the Los Angeles metropolitan area. Design, Setting, and Participants: This case series included 192 consecutive patients with reverse transcription-polymerase chain reaction (RT-PCR) test results positive for SARS-CoV-2 who were evaluated at Cedars-Sinai Medical Center in Los Angeles, California, from March 22 to April 15, 2020. Data analysis was performed from April to May 2020. Main Outcomes and Measures: SARS-CoV-2 viral genomes were sequenced. Los Angeles isolates were compared with genomes from global subsampling and from New York, New York; Washington state; and China to determine potential sources of viral dissemination. Demographic data and outcomes were collected. Results: The cohort included 192 patients (median [interquartile range] age, 59.5 [43-75] years; 110 [57.3%] men). The genetic characterization of SARS-CoV-2 isolates in the Los Angeles population pinpointed community transmission of 13 patients within a 3.81 km2 radius. Variation landscapes of this case series also revealed a cluster of 10 patients that contained 5 residents at a skilled nursing facility, 1 resident of a nearby skilled nursing facility, 3 health care workers, and a family member of a resident of one of the skilled nursing facilities. Person-to-person transmission was detected in a cluster of 5 patients who shared the same single-nucleotide variation in their SARS-CoV-2 genomes. High viral genomic diversity was identified: 20 Los Angeles isolates (15.0%) resembled SARS-CoV-2 genomes from Asia, while 109 Los Angeles isolates (82.0%) were similar to isolates originating from Europe. Analysis of other common respiratory viral pathogens did not reveal coinfection in the cohort. Conclusions and Relevance: These findings highlight the precision of detecting person-to-person transmission and accurate contact tracing directly through SARS-CoV-2 genome isolation and sequencing. Development and application of phylogenetic analyses from the Los Angeles population established connections between COVID-19 clusters locally and throughout the US.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/transmissão , Genoma Viral/genética , Pneumonia Viral/transmissão , Adulto , Idoso , Ásia , California/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Europa (Continente) , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Los Angeles/epidemiologia , Masculino , Pessoa de Meia-Idade , Cidade de Nova Iorque , Pandemias , Filogenia , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Análise de Sequência de RNA , Proteínas não Estruturais Virais/genética , Washington
3.
Am J Hum Genet ; 107(4): 622-635, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32946763

RESUMO

Quantifying the functional effects of complex disease risk variants can provide insights into mechanisms underlying disease biology. Genome-wide association studies have identified 39 regions associated with risk of epithelial ovarian cancer (EOC). The vast majority of these variants lie in the non-coding genome, where they likely function through interaction with gene regulatory elements. In this study we first estimated the heritability explained by known common low penetrance risk alleles for EOC. The narrow sense heritability (hg2) of EOC overall and high-grade serous ovarian cancer (HGSOCs) were estimated to be 5%-6%. Partitioned SNP heritability across broad functional categories indicated a significant contribution of regulatory elements to EOC heritability. We collated epigenomic profiling data for 77 cell and tissue types from Roadmap Epigenomics and ENCODE, and from H3K27Ac ChIP-seq data generated in 26 ovarian cancer and precursor-related cell and tissue types. We identified significant enrichment of risk single-nucleotide polymorphisms (SNPs) in active regulatory elements marked by H3K27Ac in HGSOCs. To further investigate how risk SNPs in active regulatory elements influence predisposition to ovarian cancer, we used motifbreakR to predict the disruption of transcription factor binding sites. We identified 469 candidate causal risk variants in H3K27Ac peaks that are predicted to significantly break transcription factor (TF) motifs. The most frequently broken motif was REST (p value = 0.0028), which has been reported as both a tumor suppressor and an oncogene. Overall, these systematic functional annotations with epigenomic data improve interpretation of EOC risk variants and shed light on likely cells of origin.


Assuntos
Carcinoma Epitelial do Ovário/genética , Proteínas Correpressoras/genética , Cistadenocarcinoma Seroso/genética , Elementos Facilitadores Genéticos , Histonas/genética , Proteínas do Tecido Nervoso/genética , Neoplasias Ovarianas/genética , Alelos , Sítios de Ligação , Carcinoma Epitelial do Ovário/diagnóstico , Carcinoma Epitelial do Ovário/patologia , Mapeamento Cromossômico , Proteínas Correpressoras/metabolismo , Cistadenocarcinoma Seroso/diagnóstico , Cistadenocarcinoma Seroso/patologia , Feminino , Predisposição Genética para Doença , Genoma Humano , Estudo de Associação Genômica Ampla , Histonas/metabolismo , Humanos , Padrões de Herança , Proteínas do Tecido Nervoso/metabolismo , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/patologia , Penetrância , Polimorfismo de Nucleotídeo Único , Risco
4.
Cell Rep Med ; 1(4): 100052, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32835305

RESUMO

Coronavirus disease 2019 (COVID-19) is a pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 is defined by respiratory symptoms, but cardiac complications including viral myocarditis are also prevalent. Although ischemic and inflammatory responses caused by COVID-19 can detrimentally affect cardiac function, the direct impact of SARS-CoV-2 infection on human cardiomyocytes is not well understood. Here, we utilize human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) as a model to examine the mechanisms of cardiomyocyte-specific infection by SARS-CoV-2. Microscopy and RNA sequencing demonstrate that SARS-CoV-2 can enter hiPSC-CMs via ACE2. Viral replication and cytopathic effect induce hiPSC-CM apoptosis and cessation of beating after 72 h of infection. SARS-CoV-2 infection activates innate immune response and antiviral clearance gene pathways, while inhibiting metabolic pathways and suppressing ACE2 expression. These studies show that SARS-CoV-2 can infect hiPSC-CMs in vitro, establishing a model for elucidating infection mechanisms and potentially a cardiac-specific antiviral drug screening platform.

5.
Cancer Res ; 80(13): 2722-2736, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32332020

RESUMO

Gastrointestinal adenocarcinomas (GIAC) of the tubular gastrointestinal (GI) tract including esophagus, stomach, colon, and rectum comprise most GI cancers and share a spectrum of genomic features. However, the unified epigenomic changes specific to GIAC are poorly characterized. Using 907 GIAC samples from The Cancer Genome Atlas, we applied mathematical algorithms to large-scale DNA methylome and transcriptome profiles to reconstruct transcription factor (TF) networks and identify a list of functionally hyperactive master regulator (MR) TF shared across different GIAC. The top candidate HNF4A exhibited prominent genomic and epigenomic activation in a GIAC-specific manner. A complex interplay between the HNF4A promoter and three distal enhancer elements was coordinated by GIAC-specific MRTF including ELF3, GATA4, GATA6, and KLF5. HNF4A also self-regulated its own promoter and enhancers. Functionally, HNF4A promoted cancer proliferation and survival by transcriptional activation of many downstream targets, including HNF1A and factors of interleukin signaling, in a lineage-specific manner. Overall, our study provides new insights into the GIAC-specific gene regulatory networks and identifies potential therapeutic strategies against these common cancers. SIGNIFICANCE: These findings show that GIAC-specific master regulatory transcription factors control HNF4A via three distal enhancers to promote GIAC cell proliferation and survival. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/13/2722/F1.large.jpg.


Assuntos
Adenocarcinoma/patologia , Biomarcadores Tumorais/metabolismo , Epigenômica , Neoplasias Gastrointestinais/patologia , Regulação Neoplásica da Expressão Gênica , Fator 4 Nuclear de Hepatócito/metabolismo , Fatores de Transcrição/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Proliferação de Células , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/metabolismo , Redes Reguladoras de Genes , Genômica , Fator 4 Nuclear de Hepatócito/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Prognóstico , Regiões Promotoras Genéticas , Taxa de Sobrevida , Fatores de Transcrição/genética , Transcriptoma , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
6.
BMC Genomics ; 20(1): 745, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619158

RESUMO

BACKGROUND: The development of next generation sequencing (NGS) methods led to a rapid rise in the generation of large genomic datasets, but the development of user-friendly tools to analyze and visualize these datasets has not developed at the same pace. This presents a two-fold challenge to biologists; the expertise to select an appropriate data analysis pipeline, and the need for bioinformatics or programming skills to apply this pipeline. The development of graphical user interface (GUI) applications hosted on web-based servers such as Shiny can make complex workflows accessible across operating systems and internet browsers to those without programming knowledge. RESULTS: We have developed GENAVi (Gene Expression Normalization Analysis and Visualization) to provide a user-friendly interface for normalization and differential expression analysis (DEA) of human or mouse feature count level RNA-Seq data. GENAVi is a GUI based tool that combines Bioconductor packages in a format for scientists without bioinformatics expertise. We provide a panel of 20 cell lines commonly used for the study of breast and ovarian cancer within GENAVi as a foundation for users to bring their own data to the application. Users can visualize expression across samples, cluster samples based on gene expression or correlation, calculate and plot the results of principal components analysis, perform DEA and gene set enrichment and produce plots for each of these analyses. To allow scalability for large datasets we have provided local install via three methods. We improve on available tools by offering a range of normalization methods and a simple to use interface that provides clear and complete session reporting and for reproducible analysis. CONCLUSION: The development of tools using a GUI makes them practical and accessible to scientists without bioinformatics expertise, or access to a data analyst with relevant skills. While several GUI based tools are currently available for RNA-Seq analysis we improve on these existing tools. This user-friendly application provides a convenient platform for the normalization, analysis and visualization of gene expression data for scientists without bioinformatics expertise.


Assuntos
Biologia Computacional/métodos , Perfilação da Expressão Gênica/métodos , Análise de Sequência de RNA/métodos , Software , Interpretação Estatística de Dados , Visualização de Dados , Internet , Reprodutibilidade dos Testes , Interface Usuário-Computador
7.
Front Psychiatry ; 7: 142, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27597832

RESUMO

Most psychiatric disorders are considered neurodevelopmental, and the associated genes often are expressed in tissues outside of the brain. This suggests a biological relatedness with medical co-occurrences that could have broad clinical implications for diagnosis and patient management over a lifetime. A qualitative integration of public data from genetic consortia of psychiatric disorders and medical comorbidities explores the question of whether genetically associated psychiatric illnesses present with co-occurring disturbances can be used to define specific mental-physical health relations. Novel patterns of gene-disorder relations appear with approximately one-third of conservatively defined, consortia-generated candidate risk genes with multiple psychiatric diagnoses. Moreover, nearly as many genes overlap with non-psychiatric phenotypes, including cardiovascular, renal, respiratory, and metabolic disturbances. While the landscape of genetic risk will change as study populations are expanded and biological confirmations accrue, the current relationships suggest that a mostly siloed perspective of gene relatedness to one categorical psychiatric diagnosis is not clinically useful. The future holds the promise that once candidates are fully validated, genome screening and mutation identification will bring more precision for predicting the risk for complex health conditions. Our view is that as genetic data are refined, continuing to decipher a shared pattern of genetic risk for brain and peripheral organ pathophysiology is not simply an academic exercise. Rather, determining relatedness will impact predictions of multifaceted health risks, patient treatment, and management.

8.
J Neurodev Disord ; 5(1): 15, 2013 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-23759142

RESUMO

BACKGROUND: Several proteins involved in epigenetic regulation cause syndromic neurodevelopmental disorders when human genes are mutated. More general involvement of epigenetic mechanisms in neurodevelopmental phenotypes is unclear. METHODS: In an attempt to determine whether DNA methylation differentiates clinical subgroups, profiling was performed on bisulfite converted DNA from lymphoblastoid cell lines (LCLs) in discovery (n = 20) and replication (n = 40) cohorts of females with Rett syndrome (RTT; n = 18), autism (AUT; n = 17), seizure disorder (SEZ; n = 6), and controls (CTL; n = 19) using Illumina HumanMethylation27 arrays. TAC1 CpGs were validated using a Sequenom EpiTYPER assay and expression was measured in LCLs and postmortem brain. Chromatin immunoprecipitation was performed in HEK cells. Cells were treated with valproic acid and MeCP2 binding was assessed. RESULTS: Two female-only cohorts were analyzed. DNA methylation profiling in a discovery cohort identified 40 CpGs that exhibited statistically significant differential methylation (≥15%) between clinical groups (P <0.01). Hierarchical clustering and principal components analysis suggested neurodevelopmental groups were distinct from CTL, but not from each other. In a larger and more heterogeneous replication cohort, these 40 CpG sites suggested no clear difference between clinical groups. Pooled analysis of DNA methylation across all 60 samples suggested only four differentially methylated CpG sites (P <0.0005), including TAC1. TAC1 promoter CpG hypermethylation was validated in AUT and SEZ (P <0.005). Analyzed for the first time in postmortem brain, TAC1 expression was reduced in cingulate cortex in RTT and AUT+SEZ (P = 0.003). However, no significant difference in TAC1 promoter CpG methylation was detected in RTT and AUT+SEZ brains. Additional molecular analyses revealed that MeCP2 binds directly to the TAC1 promoter and is sensitive to antiepileptic drug treatment. CONCLUSION: These data suggest that DNA methylation is not widely altered in RTT, consistent with subtle changes in gene expression previously observed. However, TAC1 may be an important target for further functional analyses in RTT. Studies of larger sample cohorts using primary cells that also consider shared clinical features and drug treatments may be required to address apparent subtle disruptions of DNA methylation in neurodevelopmental disorders.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...