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1.
Phys Rev Lett ; 128(2): 021601, 2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35089733

RESUMO

We find rotating black hole solutions in the Randall-Sundrum II (RSII) model, by numerically solving a three-dimensional PDE problem using pseudospectral collocation methods. We compute the area and equatorial innermost stable orbits of these solutions. For large black holes compared with the AdS length scale ℓ the black hole exhibits four-dimensional behavior, approaching the Kerr metric on the brane, while for small black holes, the solution tends instead towards a five-dimensional Myers-Perry black hole with a single nonzero rotation parameter aligned with the brane. This departure from exact four-dimensional gravity may lead to different phenomenological predictions for rotating black holes in the RSII model to those in standard four-dimensional general relativity. This Letter provides a stepping stone for studying such modifications.

2.
Proc Natl Acad Sci U S A ; 115(14): 3686-3691, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29555771

RESUMO

Reducing premature mortality associated with age-related chronic diseases, such as cancer and cardiovascular disease, is an urgent priority. We report early results using genomics in combination with advanced imaging and other clinical testing to proactively screen for age-related chronic disease risk among adults. We enrolled active, symptom-free adults in a study of screening for age-related chronic diseases associated with premature mortality. In addition to personal and family medical history and other clinical testing, we obtained whole-genome sequencing (WGS), noncontrast whole-body MRI, dual-energy X-ray absorptiometry (DXA), global metabolomics, a new blood test for prediabetes (Quantose IR), echocardiography (ECHO), ECG, and cardiac rhythm monitoring to identify age-related chronic disease risks. Precision medicine screening using WGS and advanced imaging along with other testing among active, symptom-free adults identified a broad set of complementary age-related chronic disease risks associated with premature mortality and strengthened WGS variant interpretation. This and other similarly designed screening approaches anchored by WGS and advanced imaging may have the potential to extend healthy life among active adults through improved prevention and early detection of age-related chronic diseases (and their risk factors) associated with premature mortality.


Assuntos
Doença/genética , Predisposição Genética para Doença , Processamento de Imagem Assistida por Computador/métodos , Mutação , Medicina de Precisão/métodos , Sequenciamento Completo do Genoma/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/patologia , Doença/classificação , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico por imagem , Neoplasias/genética , Neoplasias/patologia , Doenças do Sistema Nervoso/diagnóstico por imagem , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/patologia , Medição de Risco , Análise de Sequência de RNA , Adulto Jovem
3.
JAMA ; 325(22): 2262-2272, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34077499

RESUMO

Importance: Continuous glucose monitoring (CGM) has been shown to be beneficial for adults with type 2 diabetes using intensive insulin therapy, but its use in type 2 diabetes treated with basal insulin without prandial insulin has not been well studied. Objective: To determine the effectiveness of CGM in adults with type 2 diabetes treated with basal insulin without prandial insulin in primary care practices. Design, Setting, and Participants: This randomized clinical trial was conducted at 15 centers in the US (enrollment from July 30, 2018, to October 30, 2019; follow-up completed July 7, 2020) and included adults with type 2 diabetes receiving their diabetes care from a primary care clinician and treated with 1 or 2 daily injections of long- or intermediate-acting basal insulin without prandial insulin, with or without noninsulin glucose-lowering medications. Interventions: Random assignment 2:1 to CGM (n = 116) or traditional blood glucose meter (BGM) monitoring (n = 59). Main Outcomes and Measures: The primary outcome was hemoglobin A1c (HbA1c) level at 8 months. Key secondary outcomes were CGM-measured time in target glucose range of 70 to 180 mg/dL, time with glucose level at greater than 250 mg/dL, and mean glucose level at 8 months. Results: Among 175 randomized participants (mean [SD] age, 57 [9] years; 88 women [50%]; 92 racial/ethnic minority individuals [53%]; mean [SD] baseline HbA1c level, 9.1% [0.9%]), 165 (94%) completed the trial. Mean HbA1c level decreased from 9.1% at baseline to 8.0% at 8 months in the CGM group and from 9.0% to 8.4% in the BGM group (adjusted difference, -0.4% [95% CI, -0.8% to -0.1%]; P = .02). In the CGM group, compared with the BGM group, the mean percentage of CGM-measured time in the target glucose range of 70 to 180 mg/dL was 59% vs 43% (adjusted difference, 15% [95% CI, 8% to 23%]; P < .001), the mean percentage of time at greater than 250 mg/dL was 11% vs 27% (adjusted difference, -16% [95% CI, -21% to -11%]; P < .001), and the means of the mean glucose values were 179 mg/dL vs 206 mg/dL (adjusted difference, -26 mg/dL [95% CI, -41 to -12]; P < .001). Severe hypoglycemic events occurred in 1 participant (1%) in the CGM group and in 1 (2%) in the BGM group. Conclusions and Relevance: Among adults with poorly controlled type 2 diabetes treated with basal insulin without prandial insulin, continuous glucose monitoring, as compared with blood glucose meter monitoring, resulted in significantly lower HbA1c levels at 8 months. Trial Registration: ClinicalTrials.gov Identifier: NCT03566693.


Assuntos
Glicemia/análise , Diabetes Mellitus Tipo 2/tratamento farmacológico , Controle Glicêmico/métodos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Idoso , Intervalos de Confiança , Diabetes Mellitus Tipo 2/sangue , Feminino , Hemoglobinas Glicadas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Período Pós-Prandial , Tamanho da Amostra , Fatores de Tempo , Resultado do Tratamento
4.
Am J Hum Genet ; 101(5): 700-715, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-29100084

RESUMO

Short tandem repeats (STRs) are hyper-mutable sequences in the human genome. They are often used in forensics and population genetics and are also the underlying cause of many genetic diseases. There are challenges associated with accurately determining the length polymorphism of STR loci in the genome by next-generation sequencing (NGS). In particular, accurate detection of pathological STR expansion is limited by the sequence read length during whole-genome analysis. We developed TREDPARSE, a software package that incorporates various cues from read alignment and paired-end distance distribution, as well as a sequence stutter model, in a probabilistic framework to infer repeat sizes for genetic loci, and we used this software to infer repeat sizes for 30 known disease loci. Using simulated data, we show that TREDPARSE outperforms other available software. We sampled the full genome sequences of 12,632 individuals to an average read depth of approximately 30× to 40× with Illumina HiSeq X. We identified 138 individuals with risk alleles at 15 STR disease loci. We validated a representative subset of the samples (n = 19) by Sanger and by Oxford Nanopore sequencing. Additionally, we validated the STR calls against known allele sizes in a set of GeT-RM reference cell-line materials (n = 6). Several STR loci that are entirely guanine or cytosines (G or C) have insufficient read evidence for inference and therefore could not be assayed precisely by TREDPARSE. TREDPARSE extends the limit of STR size detection beyond the physical sequence read length. This extension is critical because many of the disease risk cutoffs are close to or beyond the short sequence read length of 100 to 150 bases.


Assuntos
Genoma Humano/genética , Repetições de Microssatélites/genética , Adolescente , Adulto , Alelos , Criança , Feminino , Genética Populacional/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético/genética , Análise de Sequência de DNA/métodos , Software
5.
Proc Natl Acad Sci U S A ; 114(30): 8059-8064, 2017 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-28674023

RESUMO

The HLA gene complex on human chromosome 6 is one of the most polymorphic regions in the human genome and contributes in large part to the diversity of the immune system. Accurate typing of HLA genes with short-read sequencing data has historically been difficult due to the sequence similarity between the polymorphic alleles. Here, we introduce an algorithm, xHLA, that iteratively refines the mapping results at the amino acid level to achieve 99-100% four-digit typing accuracy for both class I and II HLA genes, taking only [Formula: see text]3 min to process a 30× whole-genome BAM file on a desktop computer.


Assuntos
Teste de Histocompatibilidade/métodos , Algoritmos , Benchmarking , Humanos
6.
PLoS Pathog ; 13(3): e1006292, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28328962

RESUMO

The characterization of the blood virome is important for the safety of blood-derived transfusion products, and for the identification of emerging pathogens. We explored non-human sequence data from whole-genome sequencing of blood from 8,240 individuals, none of whom were ascertained for any infectious disease. Viral sequences were extracted from the pool of sequence reads that did not map to the human reference genome. Analyses sifted through close to 1 Petabyte of sequence data and performed 0.5 trillion similarity searches. With a lower bound for identification of 2 viral genomes/100,000 cells, we mapped sequences to 94 different viruses, including sequences from 19 human DNA viruses, proviruses and RNA viruses (herpesviruses, anelloviruses, papillomaviruses, three polyomaviruses, adenovirus, HIV, HTLV, hepatitis B, hepatitis C, parvovirus B19, and influenza virus) in 42% of the study participants. Of possible relevance to transfusion medicine, we identified Merkel cell polyomavirus in 49 individuals, papillomavirus in blood of 13 individuals, parvovirus B19 in 6 individuals, and the presence of herpesvirus 8 in 3 individuals. The presence of DNA sequences from two RNA viruses was unexpected: Hepatitis C virus is revealing of an integration event, while the influenza virus sequence resulted from immunization with a DNA vaccine. Age, sex and ancestry contributed significantly to the prevalence of infection. The remaining 75 viruses mostly reflect extensive contamination of commercial reagents and from the environment. These technical problems represent a major challenge for the identification of novel human pathogens. Increasing availability of human whole-genome sequences will contribute substantial amounts of data on the composition of the normal and pathogenic human blood virome. Distinguishing contaminants from real human viruses is challenging.


Assuntos
Sangue/virologia , Viroses/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , DNA Viral/sangue , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
7.
Proc Natl Acad Sci U S A ; 113(42): 11901-11906, 2016 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-27702888

RESUMO

We report on the sequencing of 10,545 human genomes at 30×-40× coverage with an emphasis on quality metrics and novel variant and sequence discovery. We find that 84% of an individual human genome can be sequenced confidently. This high-confidence region includes 91.5% of exon sequence and 95.2% of known pathogenic variant positions. We present the distribution of over 150 million single-nucleotide variants in the coding and noncoding genome. Each newly sequenced genome contributes an average of 8,579 novel variants. In addition, each genome carries on average 0.7 Mb of sequence that is not found in the main build of the hg38 reference genome. The density of this catalog of variation allowed us to construct high-resolution profiles that define genomic sites that are highly intolerant of genetic variation. These results indicate that the data generated by deep genome sequencing is of the quality necessary for clinical use.


Assuntos
Genoma Humano , Genômica , Sequenciamento Completo do Genoma , Mapeamento Cromossômico , Biologia Computacional/métodos , Bases de Dados de Ácidos Nucleicos , Predisposição Genética para Doença , Variação Genética , Genômica/métodos , Humanos , Fases de Leitura Aberta , Polimorfismo de Nucleotídeo Único , Reprodutibilidade dos Testes , Regiões não Traduzidas
8.
Clin Diabetes ; 37(3): 269-275, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31371858

RESUMO

IN BRIEF Therapeutic inertia and suboptimal treatment adherence remain the key drivers of chronic poor diabetes control. Advances in mHealth technologies have spurred the development of a new generation of blood glucose monitoring systems that enable individuals with diabetes to automatically transfer glucose data and other information from their smartphones to their health care providers for analysis and interpretation via diabetes data-management software. This report discusses key lessons learned from two investigations that assessed the effects of interventions using the Accu-Chek Connect diabetes-management system (Roche Diabetes Care, Indianapolis, Ind.) within diverse diabetes populations.

9.
Proc Natl Acad Sci U S A ; 112(45): 14024-9, 2015 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-26512100

RESUMO

Observations from human microbiome studies are often conflicting or inconclusive. Many factors likely contribute to these issues including small cohort sizes, sample collection, and handling and processing differences. The field of microbiome research is moving from 16S rDNA gene sequencing to a more comprehensive genomic and functional representation through whole-genome sequencing (WGS) of complete communities. Here we performed quantitative and qualitative analyses comparing WGS metagenomic data from human stool specimens using the Illumina Nextera XT and Illumina TruSeq DNA PCR-free kits, and the KAPA Biosystems Hyper Prep PCR and PCR-free systems. Significant differences in taxonomy are observed among the four different next-generation sequencing library preparations using a DNA mock community and a cell control of known concentration. We also revealed biases in error profiles, duplication rates, and loss of reads representing organisms that have a high %G+C content that can significantly impact results. As with all methods, the use of benchmarking controls has revealed critical differences among methods that impact sequencing results and later would impact study interpretation. We recommend that the community adopt PCR-free-based approaches to reduce PCR bias that affects calculations of abundance and to improve assemblies for accurate taxonomic assignment. Furthermore, the inclusion of a known-input cell spike-in control provides accurate quantitation of organisms in clinical samples.


Assuntos
Biblioteca Gênica , Genoma Bacteriano/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Metagenômica/métodos , Microbiota/genética , Análise de Variância , Composição de Bases , Sequência de Bases , Fezes/química , Humanos , Metagenômica/tendências , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Especificidade da Espécie
10.
J Reprod Med ; 60(7-8): 287-93, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26380486

RESUMO

OBJECTIVE: To develop an assay for vaginal CA125 and determine if vaginal levels correlate with the phase of the menstrual cycle. STUDY DESIGN: Fifteen women through a total of 20 ovulatory cycles obtained daily vaginal swabs for assay. Sampling began within the first 3 days after menses in and continued into the luteal phase. The subjects eluted the cotton swab tips in vials containing a standard volume of water. At the completion of each cycle the vial concentrations of CA125 were measured with the Siemens IMMULITE 2000. These "Qvaginal" levels of CA125 were indexed to the first day of positive urine luteinizing hormone signal, day 0. RESULTS: Qvaginal CA125 levels ranged from background (< 1 U/mL) to 5,740 U/mL and followed a periodic pattern: low during the early preovulatory phase, a maximum generally during day -4 to day +1, and low during the luteal phase. Qvaginal CA125 levels during the interval of presumptive fertility, day -4 to day +1, were statistically higher than levels during the preovulatory interval ending at day -5 and the postovulatory interval starting at day +2 (p value < 0.02). CONCLUSIONS: The vaginal swab assay for CA125 can potentially track the phase of the ovulatory cycle and therefore may have applications for fertility awareness and diagnosis of reproductive disorders.


Assuntos
Biomarcadores/análise , Antígeno Ca-125/análise , Ciclo Menstrual/fisiologia , Adulto , Muco do Colo Uterino/química , Feminino , Humanos , Projetos Piloto , Adulto Jovem
11.
Nat Genet ; 32(2): 245-53, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12219087

RESUMO

Type 2 diabetes results from impaired action and secretion of insulin. It is not known whether the two defects share a common pathogenesis. We show that haploinsufficiency of the Foxo1 gene, encoding a forkhead transcription factor (forkhead box transcription factor O1), restores insulin sensitivity and rescues the diabetic phenotype in insulin-resistant mice by reducing hepatic expression of glucogenetic genes and increasing adipocyte expression of insulin-sensitizing genes. Conversely, a gain-of-function Foxo1 mutation targeted to liver and pancreatic beta-cells results in diabetes arising from a combination of increased hepatic glucose production and impaired beta-cell compensation due to decreased Pdx1 expression. These data indicate that Foxo1 is a negative regulator of insulin sensitivity in liver, adipocytes and pancreatic beta-cells. Impaired insulin signaling to Foxo1 provides a unifying mechanism for the common metabolic abnormalities of type 2 diabetes.NOTE: In the AOP version of this article, the name of the fourth author was misspelled as W K Cavanee rather than the correct spelling: W K Cavenee. This has been corrected in the full-text online version of the article. The name will appear correctly in the print version.


Assuntos
Insulina/fisiologia , Ilhotas Pancreáticas/fisiologia , Fatores de Transcrição/genética , Animais , Northern Blotting , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Proteína Forkhead Box O1 , Fatores de Transcrição Forkhead , Imuno-Histoquímica , Resistência à Insulina/genética , Fígado/metabolismo , Camundongos , Camundongos Transgênicos , Mutação , Especificidade de Órgãos , Receptor de Insulina/genética , Fatores de Transcrição/fisiologia
12.
Methods ; 50(4): S6-9, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20215018

RESUMO

microRNAs are small regulatory RNAs that are currently emerging as new biomarkers for cancer and other diseases. In order for biomarkers to be useful in clinical settings, they should be accurately and reliably detected in clinical samples such as formalin fixed paraffin embedded (FFPE) sections and blood serum or plasma. These types of samples represent a challenge in terms of microRNA quantification. A newly developed method for microRNA qPCR using Locked Nucleic Acid (LNA)-enhanced primers enables accurate and reproducible quantification of microRNAs in scarce clinical samples. Here we show that LNA-based microRNA qPCR enables biomarker screening using very low amounts of total RNA from FFPE samples and the results are compared to microarray analysis data. We also present evidence that the addition of a small carrier RNA prior to total RNA extraction, improves microRNA quantification in blood plasma and laser capture microdissected (LCM) sections of FFPE samples.


Assuntos
MicroRNAs/análise , Reação em Cadeia da Polimerase/métodos , Fixadores , Formaldeído , Humanos , Lasers , MicroRNAs/sangue , MicroRNAs/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Inclusão em Parafina
13.
Diabetes Care ; 44(12): 2729-2737, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34588210

RESUMO

OBJECTIVE: To explore the effect of discontinuing continuous glucose monitoring (CGM) after 8 months of CGM use in adults with type 2 diabetes treated with basal without bolus insulin. RESEARCH DESIGN AND METHODS: This multicenter trial had an initial randomization to either real-time CGM or blood glucose monitoring (BGM) for 8 months followed by 6 months in which the BGM group continued to use BGM (n = 57) and the CGM group was randomly reassigned either to continue CGM (n = 53) or discontinue CGM with resumption of BGM for glucose monitoring (n = 53). RESULTS: In the group that discontinued CGM, mean time in range (TIR) 70-180 mg/dL, which improved from 38% before initiating CGM to 62% after 8 months of CGM, decreased after discontinuing CGM to 50% at 14 months (mean change from 8 to 14 months -12% [95% CI -21% to -3%], P = 0.01). In the group that continued CGM use, little change was found in TIR from 8 to 14 months (baseline 44%, 8 months 56%, 14 months 57%, mean change from 8 to 14 months 1% [95% CI -11% to 12%], P = 0.89). Comparing the two groups at 14 months, the adjusted treatment group difference in mean TIR was -6% (95% CI -16% to 4%, P = 0.20). CONCLUSIONS: In adults with type 2 diabetes treated with basal insulin who had been using real-time CGM for 8 months, discontinuing CGM resulted in a loss of about one-half of the initial gain in TIR that had been achieved during CGM use.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Adulto , Glicemia , Automonitorização da Glicemia/métodos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas/análise , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico
14.
Dev Cell ; 4(1): 119-29, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12530968

RESUMO

An outstanding question in adipocyte biology is how hormonal cues are relayed to the nucleus to activate the transcriptional program that promotes adipogenesis. The forkhead transcription factor Foxo1 is regulated by insulin via Akt-dependent phosphorylation and nuclear exclusion. We show that Foxo1 is induced in the early stages of adipocyte differentiation but that its activation is delayed until the end of the clonal expansion phase. Constitutively active Foxo1 prevents the differentiation of preadipocytes, while dominant-negative Foxo1 restores adipocyte differentiation of fibroblasts from insulin receptor-deficient mice. Further, Foxo1 haploinsufficiency protects from diet-induced diabetes in mice. We propose that Foxo1 plays an important role in the integration of hormone-activated signaling pathways with the complex transcriptional cascade that promotes adipocyte differentiation.


Assuntos
Adipócitos/citologia , Adipócitos/metabolismo , Diferenciação Celular , Fatores de Transcrição/metabolismo , Células 3T3 , Tecido Adiposo/crescimento & desenvolvimento , Tecido Adiposo/metabolismo , Animais , Tamanho Celular , Diabetes Mellitus/induzido quimicamente , Diabetes Mellitus/metabolismo , Gorduras na Dieta/administração & dosagem , Gorduras na Dieta/farmacologia , Fibroblastos , Proteína Forkhead Box O1 , Fatores de Transcrição Forkhead , Regulação da Expressão Gênica , Resistência à Insulina , Camundongos , Mutação/genética , Fosforilação , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Transporte Proteico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Fatores de Transcrição/genética
15.
Nat Microbiol ; 4(11): 1790-1797, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31308524

RESUMO

Diatoms are among the most globally distributed and ecologically successful organisms in the modern ocean, contributing upwards of 40% of total marine primary productivity1,2. By converting dissolved silicon into biogenic silica, and photosynthetically fixing carbon dioxide into particulate organic carbon, diatoms effectively couple the silicon (Si) and carbon cycles and ballast substantial vertical flux of carbon out of the euphotic zone into the mesopelagic and deep ocean3-5. Viruses are key players in ocean biogeochemical cycles6,7, yet little is known about how viral infection specifically impacts diatom populations. Here, we show that Si limitation facilitates virus infection and mortality in diatoms in the highly productive coastal waters of the California Current Ecosystem. Using metatranscriptomic analysis of cell-associated diatom viruses and targeted quantification of extracellular viruses, we found a link between Si stress and the early, active and lytic stages of viral infection. This relationship was also observed in cultures of the bloom-forming diatom Chaetoceros tenuissimus, where Si stress accelerated virus-induced mortality. Together, these findings contextualize viruses within the ecophysiological framework of Si availability and diatom-mediated biogeochemical cycling.


Assuntos
Diatomáceas/crescimento & desenvolvimento , Perfilação da Expressão Gênica/métodos , Silício/metabolismo , Vírus/patogenicidade , Biodegradação Ambiental , California , Carbono/metabolismo , Dióxido de Carbono , Diatomáceas/metabolismo , Diatomáceas/virologia , Metagenômica , Análise de Sequência de RNA , Vírus/classificação , Vírus/genética
16.
J Am Chem Soc ; 130(51): 17568-74, 2008 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-19053485

RESUMO

The upstream protein kinases responsible for thousands of phosphorylation events in the phosphoproteome remain to be discovered. We developed a three-component chemical reaction which converts the transient noncovalent substrate-kinase complex into a covalently cross-linked product by utilizing a dialdehyde-based cross-linker, 1. Unfortunately, the reaction of 1 with a lysine in the kinase active site and an engineered cysteine on the substrate to form an isoindole cross-linked product could not be performed in the presence of competing cellular proteins due to nonspecific side reactions. In order to more selectively target the cross-linker to protein kinases in cell lysates, we replaced the weak, kinase-binding adenosine moiety of 1 with a potent protein kinase inhibitor scaffold. In addition, we replaced the o-phthaldialdehyde moiety in 1 with a less-reactive thiophene-2,3-dicarboxaldehyde moiety. The combination of these two structural modifications provides for cross-linking of a cysteine-containing substrate to its corresponding kinase in the presence of competing cellular proteins.


Assuntos
Fosfotransferases/química , Adenosina/química , Reagentes de Ligações Cruzadas/química , Cisteína/química , Corantes Fluorescentes/química , Células HeLa , Humanos , Lisina/química , Modelos Químicos , Conformação Molecular , Peptídeos/química , Fosforilação , Fosfotransferases/metabolismo , Estrutura Terciária de Proteína , Proteínas/química , Tiofenos/química
17.
Nat Biotechnol ; 23(3): 329-36, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15711537

RESUMO

Kinase inhibitors show great promise as a new class of therapeutics. Here we describe an efficient way to determine kinase inhibitor specificity by measuring binding of small molecules to the ATP site of kinases. We have profiled 20 kinase inhibitors, including 16 that are approved drugs or in clinical development, against a panel of 119 protein kinases. We find that specificity varies widely and is not strongly correlated with chemical structure or the identity of the intended target. Many novel interactions were identified, including tight binding of the p38 inhibitor BIRB-796 to an imatinib-resistant variant of the ABL kinase, and binding of imatinib to the SRC-family kinase LCK. We also show that mutations in the epidermal growth factor receptor (EGFR) found in gefitinib-responsive patients do not affect the binding affinity of gefitinib or erlotinib. Our results represent a systematic small molecule-protein interaction map for clinical compounds across a large number of related proteins.


Assuntos
Desenho de Fármacos , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Preparações Farmacêuticas/metabolismo , Piperazinas/metabolismo , Mapeamento de Interação de Proteínas/métodos , Inibidores de Proteínas Quinases/metabolismo , Pirimidinas/metabolismo , Benzamidas , Mesilato de Imatinib , Microquímica/métodos , Ligação Proteica
18.
Cancer Res ; 66(2): 1007-14, 2006 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-16424036

RESUMO

We present a high-resolution (2.0 A) crystal structure of the catalytic domain of a mutant form of the Abl tyrosine kinase (H396P; Abl-1a numbering) that is resistant to the Abl inhibitor imatinib. The structure is determined in complex with the small-molecule inhibitor VX-680 (Vertex Pharmaceuticals, Cambridge, MA), which blocks the activity of various imatinib-resistant mutant forms of Abl, including one (T315I) that is resistant to both imatinib and BMS-354825 (dasatinib), a dual Src/Abl inhibitor that seems to be clinically effective against all other imatinib-resistant forms of BCR-Abl. VX-680 is shown to have significant inhibitory activity against BCR-Abl bearing the T315I mutation in patient-derived samples. The Abl kinase domain bound to VX-680 is not phosphorylated on the activation loop in the crystal structure but is nevertheless in an active conformation, previously unobserved for Abl and inconsistent with the binding of imatinib. The adoption of an active conformation is most likely the result of synergy between the His(396)Pro mutation, which destabilizes the inactive conformation required for imatinib binding, and the binding of VX-680, which favors the active conformation through hydrogen bonding and steric effects. VX-680 is bound to Abl in a mode that accommodates the substitution of isoleucine for threonine at residue 315 (the "gatekeeper" position). The avoidance of the innermost cavity of the Abl kinase domain by VX-680 and the specific recognition of the active conformation explain the effectiveness of this compound against mutant forms of BCR-Abl, including those with mutations at the gatekeeper position.


Assuntos
Proteínas de Fusão bcr-abl/genética , Genes abl , Piperazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-abl/química , Pirimidinas/farmacologia , Aurora Quinases , Benzamidas , Domínio Catalítico , Cristalografia , Dasatinibe , Resistencia a Medicamentos Antineoplásicos , Escherichia coli/genética , Humanos , Ligação de Hidrogênio , Mesilato de Imatinib , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Fosforilação , Conformação Proteica , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-abl/metabolismo , Tiazóis/farmacologia
19.
Sci Rep ; 8(1): 4333, 2018 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-29531289

RESUMO

Urine culture and microscopy techniques are used to profile the bacterial species present in urinary tract infections. To gain insight into the urinary flora, we analyzed clinical laboratory features and the microbial metagenome of 121 clean-catch urine samples. 16S rDNA gene signatures were successfully obtained for 116 participants, while metagenome sequencing data was successfully generated for samples from 49 participants. Although 16S rDNA sequencing was more sensitive, metagenome sequencing allowed for a more comprehensive and unbiased representation of the microbial flora, including eukarya and viral pathogens, and of bacterial virulence factors. Urine samples positive by metagenome sequencing contained a plethora of bacterial (median 41 genera/sample), eukarya (median 2 species/sample) and viral sequences (median 3 viruses/sample). Genomic analyses suggested cases of infection with potential pathogens that are often missed during routine urine culture due to species specific growth requirements. While conventional microbiological methods are inadequate to identify a large diversity of microbial species that are present in urine, genomic approaches appear to more comprehensively and quantitatively describe the urinary microbiome.


Assuntos
Bactérias/classificação , Eucariotos/classificação , Metagenoma , Infecções Urinárias/microbiologia , Infecções Urinárias/virologia , Vírus/classificação , Bactérias/genética , Bactérias/isolamento & purificação , DNA Ribossômico/genética , Eucariotos/genética , Eucariotos/isolamento & purificação , Feminino , Humanos , Masculino , Filogenia , Análise de Sequência de DNA , Infecções Urinárias/parasitologia , Infecções Urinárias/urina , Vírus/genética , Vírus/isolamento & purificação
20.
Blood Adv ; 2(19): 2419-2429, 2018 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-30262602

RESUMO

Allogeneic hematopoietic stem cell transplantation (allo-HCT) is a curative option for blood cancers, but the coupled effects of graft-versus-tumor and graft-versus-host disease (GVHD) limit its broader application. Outcomes improve with matching at HLAs, but other factors are required to explain residual risk of GVHD. In an effort to identify genetic associations outside the major histocompatibility complex, we conducted a genome-wide clinical outcomes study on 205 acute myeloid leukemia patients and their fully HLA-A-, HLA-B-, HLA-C-, HLA-DRB1-, and HLA-DQB1-matched (10/10) unrelated donors. HLA-DPB1 T-cell epitope permissibility mismatches were observed in less than half (45%) of acute GVHD cases, motivating a broader search for genetic factors affecting clinical outcomes. A novel bioinformatics workflow adapted from neoantigen discovery found no associations between acute GVHD and known, HLA-restricted minor histocompatibility antigens (MiHAs). These results were confirmed with microarray data from an additional 988 samples. On the other hand, Y-chromosome-encoded single-nucleotide polymorphisms in 4 genes (PCDH11Y, USP9Y, UTY, and NLGN4Y) did associate with acute GVHD in male patients with female donors. Males in this category with acute GVHD had more Y-encoded variant peptides per patient with higher predicted HLA-binding affinity than males without GVHD who matched X-paralogous alleles in their female donors. Methods and results described here have an immediate impact for allo-HCT, warranting further development and larger genomic studies where MiHAs are clinically relevant, including cancer immunotherapy, solid organ transplant, and pregnancy.


Assuntos
Antígenos/genética , Genes Ligados ao Cromossomo Y , Estudos de Associação Genética , Predisposição Genética para Doença , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Doença Aguda , Alelos , Sequência de Aminoácidos , Antígenos/imunologia , Mapeamento Cromossômico , Feminino , Antígenos HLA/química , Antígenos HLA/genética , Antígenos HLA/imunologia , Teste de Histocompatibilidade , Humanos , Masculino , Antígenos de Histocompatibilidade Menor/química , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/imunologia , Condicionamento Pré-Transplante/métodos , Transplante Homólogo
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