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1.
Genome Biol ; 20(1): 106, 2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-31138283

RESUMO

The explosive growth of genomic data provides an opportunity to make increased use of sequence variations for phenotype prediction. We have developed a prediction machine for quantitative phenotypes (WhoGEM) that overcomes some of the bottlenecks limiting the current methods. We demonstrated its performance by predicting quantitative disease resistance and quantitative functional traits in the wild model plant species, Medicago truncatula, using geographical locations as covariates for admixture analysis. The method's prediction reliability equals or outperforms all existing algorithms for quantitative phenotype prediction. WhoGEM analysis produces evidence that variation in genome admixture proportions explains most of the phenotypic variation for quantitative phenotypes.


Assuntos
Genômica/métodos , Aprendizado de Máquina , Medicago/genética , Fenótipo , Característica Quantitativa Herdável , Região do Mediterrâneo , Filogeografia
2.
Genome Announc ; 6(7)2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29449395

RESUMO

Bacillus spp. are ubiquitous Gram-positive microbes with many ecological and symbiotic interactions and can be pathogens. Phage Leo2 was found to infect a Bacillus pumilus strain isolated from soil. The sequence of phage Leo2 revealed 74 genes; 31% of the genes have associated functions, and 67% of coding regions are unidentified open reading frames.

3.
Am Heart J ; 167(3): 335-41, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24576517

RESUMO

Randomized clinical trials have identified a population of acute medically ill patients who remain at risk for venous thromboembolism (VTE) beyond the standard duration of therapy and hospital discharge. The aim of the APEX study is to determine whether extended administration of oral betrixaban (35-42 days) is superior to a standard short course of prophylaxis with subcutaneous enoxaparin (10 ± 4 days followed by placebo) in patients with known risk factors for post-discharge VTE. Patients initially are randomized to receive either betrixaban or enoxaparin (and matching placebo) in a double dummy design. Following a standard duration period of enoxaparin treatment (with placebo tablets) or betrixaban (with placebo injections), patients receive only betrixaban (or alternative matching placebo). Patients are considered for enrollment if they are older than 40 years, have a specified medical illness, and restricted mobility. They must also meet the APEX criteria for increased VTE risk (aged ≥75 years, baseline D-Dimer ≥2× upper the limit of "normal", or 2 additional ancillary risk factors for VTE). The primary efficacy end point is the composite of asymptomatic proximal deep venous thrombosis, symptomatic deep venous thrombosis, non-fatal (pulmonary embolus) pulmonary embolism, or VTE-related death through day 35. The primary safety outcome is the occurrence of major bleeding. We hypothesize that extended duration betrixaban VTE prophylaxis will be safe and more effective than standard short duration enoxaparin in preventing VTE in acute medically ill patients with known risk factors for post hospital discharge VTE.


Assuntos
Anticoagulantes/administração & dosagem , Benzamidas/administração & dosagem , Enoxaparina/administração & dosagem , Inibidores do Fator Xa , Piridinas/administração & dosagem , Tromboembolia Venosa/prevenção & controle , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Humanos , Internacionalidade , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
4.
Mol Biol Cell ; 23(22): 4416-29, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22993212

RESUMO

Clathrin coat accessory proteins play key roles in transport mediated by clathrin-coated vesicles. Yeast Irc6p and the related mammalian p34 are putative clathrin accessory proteins that interact with clathrin adaptor complexes. We present evidence that Irc6p functions in clathrin-mediated traffic between the trans-Golgi network and endosomes, linking clathrin adaptor complex AP-1 and the Rab GTPase Ypt31p. The crystal structure of the Irc6p N-terminal domain revealed a G-protein fold most related to small G proteins of the Rab and Arf families. However, Irc6p lacks G-protein signature motifs and high-affinity GTP binding. Also, mutant Irc6p lacking candidate GTP-binding residues retained function. Mammalian p34 rescued growth defects in irc6 cells, indicating functional conservation, and modeling predicted a similar N-terminal fold in p34. Irc6p and p34 also contain functionally conserved C-terminal regions. Irc6p/p34-related proteins with the same two-part architecture are encoded in genomes of species as diverse as plants and humans. Together these results define Irc6p/p34 as a novel type of conserved clathrin accessory protein and founding members of a new G protein-like family.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/fisiologia , Proteínas Monoméricas de Ligação ao GTP/fisiologia , Proteínas de Saccharomyces cerevisiae/fisiologia , Fator 1 de Ribosilação do ADP/química , Proteínas Adaptadoras de Transporte Vesicular/química , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Sequência de Aminoácidos , Transporte Biológico , Clatrina/metabolismo , Sequência Conservada , Cristalografia por Raios X , Endossomos/metabolismo , Dados de Sequência Molecular , Proteínas Monoméricas de Ligação ao GTP/química , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Mapeamento de Interação de Proteínas , Estrutura Terciária de Proteína , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Alinhamento de Sequência , Proteínas rab de Ligação ao GTP/química , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo , Rede trans-Golgi/metabolismo , Rede trans-Golgi/fisiologia
5.
Am Heart J ; 164(3): 379-386.e1, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22980305

RESUMO

BACKGROUND: Edifoligide, an E2F transcription factor decoy, does not prevent vein graft failure or adverse clinical outcomes at 1 year in patients undergoing coronary artery bypass grafting (CABG). We compared the 5-year clinical outcomes of patients in PREVENT IV treated with edifoligide and placebo to identify predictors of long-term clinical outcomes. METHODS: A total of 3,014 patients undergoing CABG with at least 2 planned vein grafts were enrolled. Kaplan-Meier curves were generated to compare the long-term effects of edifoligide and placebo. A Cox proportional hazards model was constructed to identify factors associated with 5-year post-CABG outcomes. The main outcome measures were death, myocardial infarction (MI), repeat revascularization, and rehospitalization through 5 years. RESULTS: Five-year follow-up was complete in 2,865 patients (95.1%). At 5 years, patients randomized to edifoligide and placebo had similar rates of death (11.7% and 10.7%, respectively), MI (2.3% and 3.2%), revascularization (14.1% and 13.9%), and rehospitalization (61.6% and 62.5%). The composite outcome of death, MI, or revascularization occurred at similar frequency in patients assigned to edifoligide and placebo (26.3% and 25.5%, respectively; hazard ratio 1.03 [95% CI 0.89-1.18], P = .721). Factors associated with death, MI, or revascularization at 5 years included peripheral and/or cerebrovascular disease, time on cardiopulmonary bypass, lung disease, diabetes mellitus, and congestive heart failure. CONCLUSIONS: Up to a quarter of patients undergoing CABG will have a major cardiac event or repeat revascularization procedure within 5 years of surgery. Edifoligide does not affect outcomes after CABG; however, common identifiable baseline and procedural risk factors are associated with long-term outcomes after CABG.


Assuntos
Ponte de Artéria Coronária , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/cirurgia , Oligonucleotídeos/uso terapêutico , Complicações Pós-Operatórias , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Doença da Artéria Coronariana/mortalidade , Método Duplo-Cego , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Revascularização Miocárdica/estatística & dados numéricos , Readmissão do Paciente/estatística & dados numéricos , Modelos de Riscos Proporcionais , Resultado do Tratamento , Adulto Jovem
6.
J Vis Exp ; (63): e3998, 2012 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-22664923

RESUMO

In the biological sciences there have been technological advances that catapult the discipline into golden ages of discovery. For example, the field of microbiology was transformed with the advent of Anton van Leeuwenhoek's microscope, which allowed scientists to visualize prokaryotes for the first time. The development of the polymerase chain reaction (PCR) is one of those innovations that changed the course of molecular science with its impact spanning countless subdisciplines in biology. The theoretical process was outlined by Keppe and coworkers in 1971; however, it was another 14 years until the complete PCR procedure was described and experimentally applied by Kary Mullis while at Cetus Corporation in 1985. Automation and refinement of this technique progressed with the introduction of a thermal stable DNA polymerase from the bacterium Thermus aquaticus, consequently the name Taq DNA polymerase. PCR is a powerful amplification technique that can generate an ample supply of a specific segment of DNA (i.e., an amplicon) from only a small amount of starting material (i.e., DNA template or target sequence). While straightforward and generally trouble-free, there are pitfalls that complicate the reaction producing spurious results. When PCR fails it can lead to many non-specific DNA products of varying sizes that appear as a ladder or smear of bands on agarose gels. Sometimes no products form at all. Another potential problem occurs when mutations are unintentionally introduced in the amplicons, resulting in a heterogeneous population of PCR products. PCR failures can become frustrating unless patience and careful troubleshooting are employed to sort out and solve the problem(s). This protocol outlines the basic principles of PCR, provides a methodology that will result in amplification of most target sequences, and presents strategies for optimizing a reaction. By following this PCR guide, students should be able to: • Set up reactions and thermal cycling conditions for a conventional PCR experiment • Understand the function of various reaction components and their overall effect on a PCR experiment • Design and optimize a PCR experiment for any DNA template • Troubleshoot failed PCR experiments.


Assuntos
Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/tendências
8.
Am Heart J ; 157(2): 271-7, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19185633

RESUMO

BACKGROUND: Acute decompensated heart failure (ADHF) is a major public health burden with significant mortality and morbidity. Nesiritide is a recombinantly produced intravenous formulation of human B-type natriuretic peptide that promotes vasodilation and increases salt and water excretion, which results in reduced cardiac filling pressures. Prior studies have shown that dyspnea is improved in patients with ADHF 3 hours after nesiritide infusion with significant dose-related reductions in cardiac filling pressures and systemic vascular resistance without significant arrhythmias. However, the effect of nesiritide on dyspnea at 6 or 24 hours is unknown, and no clinical outcome trials have been done to provide a reliable estimate of the effect of nesiritide on morbidity and mortality. METHODS: The Acute Study of Clinical Effectiveness of Nesiritide in Decompensated Heart Failure trial (ASCEND-HF) is a phase III study evaluating the efficacy and safety of nesiritide in patients with ADHF. Patients hospitalized for hear failure will be randomly assigned to receive either intravenous nesiritide or matching placebo for 24 hours to 7 days. The 2 coprimary end points are (1) assessment of acute dyspnea at 6 or 24 hours and (2) death or rehospitalization for hear failure within 30 days. A total of 7,000 patients will be enrolled worldwide between 2007 and 2010. CONCLUSIONS: The data from the ASCEND-HF trial will establish whether nesiritide safely improves acute dyspnea as well as morbidity and mortality at 30 days.


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Natriuréticos/uso terapêutico , Peptídeo Natriurético Encefálico/uso terapêutico , Dispneia/tratamento farmacológico , Dispneia/etiologia , Insuficiência Cardíaca/epidemiologia , Hospitalização , Humanos , Morbidade , Projetos de Pesquisa , Análise de Sobrevida , Resultado do Tratamento
9.
Mol Biol Cell ; 20(5): 1592-604, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19116312

RESUMO

The evolutionarily conserved adaptor protein-3 (AP-3) complex mediates cargo-selective transport to lysosomes and lysosome-related organelles. To identify proteins that function in AP-3-mediated transport, we performed a genome-wide screen in Saccharomyces cerevisiae for defects in the vacuolar maturation of alkaline phosphatase (ALP), a cargo of the AP-3 pathway. Forty-nine gene deletion strains were identified that accumulated precursor ALP, many with established defects in vacuolar protein transport. Maturation of a vacuolar membrane protein delivered via a separate, clathrin-dependent pathway, was affected in all strains except those with deletions of YCK3, encoding a vacuolar type I casein kinase; SVP26, encoding an endoplasmic reticulum (ER) export receptor for ALP; and AP-3 subunit genes. Subcellular fractionation and fluorescence microscopy revealed ALP transport defects in yck3Delta cells. Characterization of svp26Delta cells revealed a role for Svp26p in ER export of only a subset of type II membrane proteins. Finally, ALP maturation kinetics in vac8Delta and vac17Delta cells suggests that vacuole inheritance is important for rapid generation of proteolytically active vacuolar compartments in daughter cells. We propose that the cargo-selective nature of the AP-3 pathway in yeast is achieved by AP-3 and Yck3p functioning in concert with machinery shared by other vacuolar transport pathways.


Assuntos
Complexo 3 de Proteínas Adaptadoras/fisiologia , Fosfatase Alcalina/metabolismo , Proteínas de Saccharomyces cerevisiae/fisiologia , Saccharomyces cerevisiae/metabolismo , Vacúolos/metabolismo , Complexo 3 de Proteínas Adaptadoras/genética , Fosfatase Alcalina/análise , Caseína Quinase I/genética , Caseína Quinase I/metabolismo , Caseína Quinase I/fisiologia , Deleção de Genes , Genoma Fúngico , Proteínas de Fluorescência Verde/análise , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Membrana/fisiologia , Subunidades Proteicas/genética , Transporte Proteico/genética , Transporte Proteico/fisiologia , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Transporte Vesicular
10.
Methods Mol Biol ; 457: 13-27, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19066016

RESUMO

A variety of Saccharomyces cerevisiae strain libraries allow for systematic analysis of strains bearing gene deletions, repressible genes, overexpressed genes, or modified genes on a genome-wide scale. Here we introduce a method for culturing yeast strains in 96-well format to achieve log-phase growth and a high-throughput technique for generating whole-cell protein extracts from these cultures using sodium dodecyl sulfate and heat lysis. We subsequently describe a procedure to analyze these whole-cell extracts by immunoblotting for alkaline phosphatase and carboxypeptidase yscS to identify strains with defects in protein transport pathways or protein glycosylation. These methods should be readily adaptable to many different areas of interest.


Assuntos
Bioquímica/métodos , Immunoblotting/métodos , Proteínas de Saccharomyces cerevisiae/isolamento & purificação , Saccharomyces cerevisiae/metabolismo , Fosfatase Alcalina/metabolismo , Carboxipeptidases/metabolismo , Eletroforese em Gel de Poliacrilamida , Fermentação , Genes Fúngicos , Glicosilação , Transporte Proteico , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento
11.
J Biol Chem ; 281(46): 35520-30, 2006 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-16973627

RESUMO

The AGCVIIIa kinases of Arabidopsis are members of the eukaryotic PKA, PKG, and PKC group of regulatory kinases. One AGCVIIIa kinase, PINOID (PID), plays a fundamental role in the asymmetrical localization of membrane proteins during polar auxin transport. The remaining 16 AGCVIIIa genes have not been associated with single mutant phenotypes, suggesting that the corresponding kinases function redundantly. Consistent with this idea, we find that the genes encoding the Arabidopsis AGCVIIIa kinases have spatially distinct, but overlapping, expression domains. Here we show that the majority of Arabidopsis AGCVIIIa kinases are substrates for the 3-phosphoinositide-dependent kinase 1 (PDK1) and that trans-phosphorylation by PDK1 correlates with activation of substrate AGCVIIIa kinases. Mutational analysis of two conserved regulatory domains was used to demonstrate that sequences located outside of the C-terminal PDK1 interaction (PIF) domain and the activation loop are required for functional interactions between PDK1 and its substrates. A subset of GFP-tagged AGCVIIIa kinases expressed in Saccharomyces cerevisiae and tobacco BY-2 cells were preferentially localized to the cytoplasm (AGC1-7), nucleus (WAG1 and KIPK), and the cell periphery (PID). We present evidence that PID insertion domain sequences are sufficient to direct the observed peripheral localization. We find that PID specifically but non-selectively binds to phosphoinositides and phosphatidic acid, suggesting that PID might directly interact with the plasma membrane through protein-lipid interactions. The initial characterization of the AGCVIIIa kinases presented here provides a framework for elucidating the physiological roles of these kinases in planta.


Assuntos
Arabidopsis/enzimologia , Proteínas Quinases/metabolismo , Proteínas Quinases Dependentes de 3-Fosfoinositídeo , Sequência de Aminoácidos , Ativação Enzimática , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Proteínas Quinases/genética , Processamento de Proteína Pós-Traducional , Proteínas Serina-Treonina Quinases/metabolismo , Transporte Proteico
12.
Cell ; 126(3): 611-25, 2006 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-16901791

RESUMO

Discovering target and off-target effects of specific compounds is critical to drug discovery and development. We generated a compendium of "chemical-genetic interaction" profiles by testing the collection of viable yeast haploid deletion mutants for hypersensitivity to 82 compounds and natural product extracts. To cluster compounds with a similar mode-of-action and to reveal insights into the cellular pathways and proteins affected, we applied both a hierarchical clustering and a factorgram method, which allows a gene or compound to be associated with more than one group. In particular, tamoxifen, a breast cancer therapeutic, was found to disrupt calcium homeostasis and phosphatidylserine (PS) was recognized as a target for papuamide B, a cytotoxic lipopeptide with anti-HIV activity. Further, the profile of crude extracts resembled that of its constituent purified natural product, enabling detailed classification of extract activity prior to purification. This compendium should serve as a valuable key for interpreting cellular effects of novel compounds with similar activities.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Resistência a Medicamentos/genética , Perfilação da Expressão Gênica/métodos , Preparações Farmacêuticas/metabolismo , Leveduras/efeitos dos fármacos , Leveduras/genética , Antineoplásicos Hormonais/farmacologia , Antivirais/farmacologia , Análise por Conglomerados , Depsipeptídeos/farmacologia , Proteínas Fúngicas/efeitos dos fármacos , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Estrutura Molecular , Mutação/efeitos dos fármacos , Mutação/genética , Preparações Farmacêuticas/química , Preparações Farmacêuticas/classificação , Fosfatidilserinas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Tamoxifeno/farmacologia , Leveduras/metabolismo
13.
J Vasc Surg ; 43(4): 742-751; discussion 751, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16616230

RESUMO

OBJECTIVE: The PREVENT III study was a prospective, randomized, double-blinded, multicenter phase III trial of a novel molecular therapy (edifoligide; E2F decoy) for the prevention of vein graft failure in patients undergoing infrainguinal revascularization for critical limb ischemia (CLI). METHODS: From November 2001 through October 2003, 1404 patients with CLI were randomized to a single intraoperative ex vivo vein graft treatment with edifoligide or placebo. After surgery, patients underwent graft surveillance by duplex ultrasonography and were followed up for index graft and limb end points to 1 year. A blinded Clinical Events Classification committee reviewed all index graft end points. The primary study end point was the time to nontechnical index graft reintervention or major amputation due to index graft failure. Secondary end points included all-cause graft failure, clinically significant graft stenosis (>70% by angiography or severe stenosis by ultrasonography), amputation/reintervention-free survival, and nontechnical primary graft patency. Event rates were based on Kaplan-Meier estimates. Time-to-event end points were compared by using the log-rank test. RESULTS: Demographics, comorbidities, and procedural details reflected a population with CLI and diffuse atherosclerosis. Tissue loss was the presenting symptom in 75% of patients. High-risk conduits were used in 24% of cases, including an alternative vein in 20% (15% spliced vein and 5% non-great saphenous vein) and 6% less than 3 mm in diameter; 14% of the cases were reoperative bypass grafts. Most (65%) grafts were placed to infrapopliteal targets. Perioperative (30-day) mortality occurred in 2.7% of patients. Major morbidity included myocardial infarction in 4.7% and early graft occlusion in 5.2% of patients. Ex vivo treatment with edifoligide was well tolerated. There was no significant difference between the treatment groups in the primary or secondary trial end points, primary graft patency, or limb salvage. A statistically significant improvement was observed in secondary graft patency (estimated Kaplan-Meier rates were 83% edifoligide and 78% placebo; P = .016) within 1 year. The reduction in secondary patency events was manifest within 30 days of surgery (the relative risk for a 30-day event for edifoligide was 0.45; 95% confidence interval, 0.27-0.76; P = .005). For the overall cohort at 1 year, the estimated Kaplan-Meier rate for survival was 84%, that for primary patency was 61%, that for primary assisted patency was 77%, that for secondary patency was 80%, and that for limb salvage was 88%. CONCLUSIONS: In this prospective, randomized, placebo-controlled clinical trial, ex vivo treatment of lower extremity vein grafts with edifoligide did not confer protection from reintervention for graft failure.


Assuntos
Fatores de Transcrição E2F/uso terapêutico , Oclusão de Enxerto Vascular/tratamento farmacológico , Oclusão de Enxerto Vascular/prevenção & controle , Doenças Vasculares Periféricas/cirurgia , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Seguimentos , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Humanos , Extremidade Inferior/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Doenças Vasculares Periféricas/diagnóstico por imagem , Complicações Pós-Operatórias/prevenção & controle , Estudos Prospectivos , Valores de Referência , Medição de Risco , Índice de Gravidade de Doença , Resultado do Tratamento , Ultrassonografia Doppler , Grau de Desobstrução Vascular/efeitos dos fármacos , Procedimentos Cirúrgicos Vasculares/métodos
14.
JAMA ; 294(19): 2446-54, 2005 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-16287955

RESUMO

CONTEXT: Coronary artery bypass graft (CABG) surgery with autologous vein grafting is commonly performed. Progressive neointimal hyperplasia, however, contributes to considerable vein graft failure. Edifoligide is an oligonucleotide decoy that binds to and inhibits E2F transcription factors and thus may prevent neointimal hyperplasia and vein graft failure. OBJECTIVE: To assess the efficacy and safety of pretreating vein grafts with edifoligide for patients undergoing CABG surgery. DESIGN, SETTING, AND PARTICIPANTS: A phase 3 randomized, double-blind, placebo-controlled trial of 3014 patients undergoing primary CABG surgery with at least 2 planned saphenous vein grafts and without concomitant valve surgery, who were enrolled between August 2002 and October 2003 at 107 US sites. INTERVENTION: Vein grafts were treated ex vivo with either edifoligide or placebo in a pressure-mediated delivery system. The first 2400 patients enrolled were scheduled for 12- to 18-month follow-up angiography. MAIN OUTCOME MEASURES: The primary efficacy end point was angiographic vein graft failure (> or =75% vein graft stenosis) occurring 12 to 18 months after CABG surgery. Other end points included other angiographic variables, adverse events through 30 days, and major adverse cardiac events. RESULTS: A total of 1920 patients (80%) either died (n = 91) or underwent follow-up angiography (n = 1829). Edifoligide had no effect on the primary end point of per patient vein graft failure (436 [45.2%] of 965 patients in the edifoligide group vs 442 [46.3%] of 955 patients in the placebo group; odds ratio, 0.96 [95% confidence interval {CI}, 0.80-1.14]; P = .66), on any secondary angiographic end point, or on the incidence of major adverse cardiac events at 1 year (101 [6.7%] of 1508 patients in the edifoligide group vs 121 [8.1%] of 1506 patients in the placebo group; hazard ratio, 0.83 [95% CI, 0.64-1.08]; P = .16). CONCLUSIONS: Failure of at least 1 vein graft is quite common within 12 to 18 months after CABG surgery. Edifoligide is no more effective than placebo in preventing these events. Longer-term follow-up and additional research are needed to determine whether edifoligide has delayed beneficial effects, to understand the mechanisms and clinical consequences of vein graft failure, and to improve the durability of CABG surgery. Clinical Trial Registration ClinicalTrials.gov Identifier: NCT00042081.


Assuntos
Ponte de Artéria Coronária , DNA/uso terapêutico , Terapia Genética , Oclusão de Enxerto Vascular/prevenção & controle , Oligonucleotídeos/uso terapêutico , Veia Safena/efeitos dos fármacos , Veia Safena/transplante , Transplantes , Grau de Desobstrução Vascular/efeitos dos fármacos , Idoso , Angiografia , Método Duplo-Cego , Fatores de Transcrição E2F , Feminino , Terapia Genética/métodos , Humanos , Hiperplasia , Masculino , Pessoa de Meia-Idade , Veia Safena/diagnóstico por imagem , Veia Safena/patologia , Análise de Sobrevida , Coleta de Tecidos e Órgãos , Transfecção , Transplante Autólogo
15.
Am J Cardiol ; 96(9): 1254-9, 2005 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16253593

RESUMO

Up to 20% of saphenous vein grafts (SVGs) fail within 2 years of coronary artery bypass grafting (CABG). The long-term effects of early SVG failure on major clinical events remain undefined in contemporary patient populations. We sought to examine the relation between early SVG failure and long-term outcomes after CABG. Using the Duke Cardiovascular Databank, we examined baseline clinical and angiographic characteristics and clinical outcomes among patients who underwent catheterization 1 to 18 months after their first CABG from 1986 to 2004. Patients were classified on the basis of their worst SVG stenosis as having no (<25%), noncritical (25% to 74%), critical (75% to 99%), or occlusive (100%) SVG disease. Our primary outcome measure was the composite of death, myocardial infarction, or repeat revascularization after catheterization. Of 1,243 patients included in the analysis, 27.9% had no, 11.9% had noncritical, 20.8% had critical, and 39.3% had occlusive SVG disease. At 10 years, the corresponding adjusted composite event rates were 41.2%, 56.2%, 81.2%, and 67.1%, respectively (p <0.0001). Most events occurred immediately after catheterization in patients with critical and occlusive SVG disease and were primarily repeat revascularization. On multivariate analysis, critical, nonocclusive SVG disease was the strongest predictor of the composite outcome (hazard ratio 2.36, 95% confidence interval 2.00 to 2.79, p <0.0001). In conclusion, in contemporary clinical practice, early SVG failure is associated with worse long-term outcomes after CABG.


Assuntos
Ponte de Artéria Coronária/métodos , Estenose Coronária/cirurgia , Oclusão de Enxerto Vascular , Veia Safena/transplante , Idoso , Angiografia Coronária , Estenose Coronária/diagnóstico por imagem , Feminino , Seguimentos , Oclusão de Enxerto Vascular/complicações , Oclusão de Enxerto Vascular/mortalidade , Oclusão de Enxerto Vascular/terapia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/terapia , Revascularização Miocárdica/estatística & dados numéricos , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
16.
Am Heart J ; 150(4): 643-9, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16209958

RESUMO

BACKGROUND: Coronary artery bypass graft (CABG) surgery with autologous vein graft (VG) conduit is one of the most frequently performed operations in the United States. Unfortunately, many VGs become occluded during long-term follow-up largely because of neointimal hyperplasia. A novel approach to preventing neointimal hyperplasia is with the double-stranded oligonucleotide edifoligide (Corgentech Inc, South San Francisco, Calif). Edifoligide inhibits E2F, a transcription factor that activates cell-cycle genes responsible for neointimal hyperplasia. METHODS: PREVENT IV is a phase-III, multicenter, randomized double-blind placebo-controlled trial of ex vivo treatment of autologous VGs with edifoligide in patients undergoing initial CABG surgery. The primary end point is VG failure, defined as death or > or =75% stenosis in a treated VG at 12- to 18-month angiographic follow-up. Secondary end points include major adverse cardiac events through at least 5 years and adverse events through 30 days. RESULTS: Enrollment of 3014 patients from 107 sites was completed on October 22, 2003. The baseline and procedural characteristics of the PREVENT IV population are generally well matched to a contemporary population of patients undergoing initial CABG from the Society of Thoracic Surgeons National Database. Angiographic follow-up is ongoing and scheduled to be completed in March 2005. CONCLUSIONS: The PREVENT IV data will establish whether VG pretreatment with an E2F transcription factor decoy, edifoligide, can improve graft patency and reduce the long-term morbidity and mortality of patients undergoing CABG surgery.


Assuntos
Ponte de Artéria Coronária/métodos , DNA/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Idoso , Ponte de Artéria Coronária/efeitos adversos , Desenho de Equipamento , Feminino , Seguimentos , Humanos , Hiperplasia/prevenção & controle , Injeções Intravenosas/instrumentação , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Oligonucleotídeos , Complicações Pós-Operatórias/prevenção & controle , Projetos de Pesquisa , Túnica Íntima/patologia
17.
Vasc Endovascular Surg ; 39(1): 15-23, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15696244

RESUMO

Surgical bypass of peripheral arterial occlusive disease with autologous vein grafts provides an effective means of restoring blood flow to the lower extremity, and has been a standard therapy for patients with disabling claudication or critical limb ischemia (CLI). However, failure rates may run as high as 50% within 5 years. These graft failures occur as a result of neointimal hyperplasia, a ubiquitous biologic response of blood vessel walls to injury, which is characterized by the migration and proliferation of smooth muscle cells (SMC). The E2F family of transcription factors regulates the expression of genes controlling SMC proliferation. Edifoligide (E2F Decoy) is a novel therapy that inhibits E2F function, thus attenuating neointimal hyperplasia. Its use in conjunction with a patented drug delivery pressurization chamber is under investigation. Using this system, edifoligide is administered to vein grafts in a single, ex vivo treatment following vein harvest and before implantation, resulting in minimal systemic drug exposure and excellent patient compliance. This Phase 3, randomized, double-blind, multicenter clinical trial is designed to evaluate the safety and efficacy of edifoligide in a population of approximately 1400 patients with CLI undergoing infrainguinal bypass for peripheral arterial disease (PAD). The primary outcome measure will be the time to occurrence of non-technical graft failure resulting in either graft revision or major amputation at 12 months after enrollment. A governing Clinical Events Classification committee (CEC) will adjudicate each graft failure to determine its etiology. The PREVENT III trial is the largest multicenter trial ever performed in patients receiving autologous vein bypass grafts for CLI. This landmark study will determine if edifoligide is safe and effective at preventing vein graft failure in patients undergoing lower extremity bypass, but it also provides a unique opportunity to observe current treatment practices in vascular surgery.


Assuntos
Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ligação a DNA/antagonistas & inibidores , Oclusão de Enxerto Vascular/prevenção & controle , Músculo Liso Vascular/efeitos dos fármacos , Oligonucleotídeos/uso terapêutico , Fatores de Transcrição/antagonistas & inibidores , Arteriopatias Oclusivas/cirurgia , Prótese Vascular , Implante de Prótese Vascular , Ensaios Clínicos Fase III como Assunto , Fatores de Transcrição E2F , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Veias/efeitos dos fármacos
18.
J Interv Cardiol ; 16(2): 97-105, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12768912

RESUMO

Rarely is it straightforward to specify the design and parameters of a clinical trial investigating an alternative therapy where effective therapies already exist. If existing therapeutic interventions are highly efficacious, safe, inexpensive, and firmly entrenched, an active-control design becomes the logical first choice. Short of this absolute condition, however, the merits and realities of the scientific, clinical, corporate, and regulatory environments need to be weighed before determining the appropriate approach. A state of clinical equipoise with regard to the use of glycoprotein (GP) IIb/IIIa therapy in percutaneous coronary intervention (PCI) provided the unique opportunity to address the complexities in selecting a placebo-controlled design for the Enhanced Suppression of the Platelet IIb/IIIa Receptor with Integrilin Trial (ESPRIT). ESPRIT investigators assessed whether a high dose of eptifibatide would improve the outcomes of patients undergoing coronary stenting. By using the example of the ESPRIT trial, we examine factors warranting the need for this trial and evaluate the process whereby the United States Food and Drug Administration (FDA) gave approval for a placebo-controlled design. Although the focus of this trial is GP IIb/IIIa inhibition therapy, the issues pertaining to the trial and how they were resolved are general enough to be applied to the design and conduct of clinical trials across a broad spectrum of illnesses and therapeutic modalities.


Assuntos
Ensaios Clínicos Controlados como Assunto/ética , Ensaios Clínicos Controlados como Assunto/métodos , Doença das Coronárias/terapia , Ética em Pesquisa , Placebos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Angioplastia Coronária com Balão , Doença das Coronárias/tratamento farmacológico , Determinação de Ponto Final , Eptifibatida , Humanos , Avaliação de Resultados em Cuidados de Saúde , Peptídeos/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Projetos de Pesquisa , Stents , Estados Unidos , United States Food and Drug Administration
19.
J Am Coll Cardiol ; 40(6): 1085-91, 2002 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-12354432

RESUMO

OBJECTIVE: The study was done to determine whether eptifibatide, a platelet glycoprotein (GP) IIb/IIIa antagonist, prevents ischemic complications following percutaneous coronary interventions (PCIs) in women as well as in men. BACKGROUND: Eptifibatide reduces ischemic complications after nonurgent coronary stent interventions. METHODS: We compared outcomes in women (n = 562) and men (n = 1,502) enrolled in the Enhanced Suppression of the Platelet GP IIb/IIIa Receptor with Integrilin Therapy (ESPRIT) trial of double-bolus eptifibatide during PCI. RESULTS: Women in the ESPRIT trial were older, and more frequently had hypertension, diabetes mellitus, or acute coronary syndromes, but were less likely to have prior PCI or coronary artery bypass graft surgery. The primary end point, a composite at 48 h of death, myocardial infarction (MI), urgent target vessel revascularization (TVR), and unplanned GP IIb/IIIa use, occurred in 10.5% of women and 7.9% of men (p = 0.082). The composite of death, MI, or TVR after one year occurred in 24.5% of women compared with 18% of men (p = 0.0008). At 48 h, eptifibatide reduced the composite of death, MI, and TVR from 14.5% to 6.0% in women versus 9.0% to 6.8% in men. At one year, these differences persisted: 28.9% versus 20.0% for women and 19.5% versus 16.6% for men. No statistical interaction existed between treatment and gender at either 48 h (p = 0.063) or one year (p = 0.2). Bleeding occurred more commonly in women (5.5% vs. 2.6%, p = 0.002), and was more common in eptifibatide-treated women. After adjustment for age, weight, and hypertension, no interaction between treatment and gender was present. CONCLUSION: Eptifibatide is effective to prevent ischemic complications of PCI in women and may eliminate gender-related differences in PCI outcomes.


Assuntos
Angioplastia Coronária com Balão/efeitos adversos , Isquemia Miocárdica/etiologia , Isquemia Miocárdica/prevenção & controle , Peptídeos/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/uso terapêutico , Complicações Pós-Operatórias , Idoso , Eptifibatida , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Estudos Retrospectivos , Fatores Sexuais
20.
Am Heart J ; 143(1): 106-10, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11773919

RESUMO

BACKGROUND: The etiology of creatine kinase-myocardial band (CK-MB) release after percutaneous coronary intervention (PCI) remains unclear. The goal of this study was to evaluate the relationship of both epicardial and tissue level perfusion at the completion of stent placement to CK-MB release after the procedure. Given the high rates of Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow after PCI, we hypothesized that abnormalities in tissue level perfusion would instead explain CK-MB release. METHODS: Data were drawn from the angiographic substudy of the Enhanced Suppression of the Platelet IIb/IIIa Receptor With Integrilin Therapy (ESPRIT) trial of eptifibatide versus placebo in patients undergoing planned coronary stent implantation. In the substudy, cinefilms of 65 patients were analyzed by an angiographic core laboratory blinded to enzymatic and clinical outcomes. RESULTS: The release of CK-MB was not associated with TIMI grade 3 flow or the corrected TIMI frame count; 100% of patients had TIMI grade 3 flow at the completion of PCI. In contrast, tissue level perfusion using the TIMI myocardial perfusion grade (TMPG) was related to postintervention CK-MB release: patients with a closed myocardium (TMPG 0/1) or delayed myocardial perfusion (TMPG 2) had an average CK-MB release 2.2 +/- 2.7 times the upper limit of normal (n = 34), whereas those patients with normal myocardial perfusion (TMPG 3, n = 24) had CK-MB 0.8 +/- 0.6 times the upper limit of normal (P =.01). Although no patients with TMPG 3 sustained death/myocardial infarction/urgent target vessel revascularization or thrombotic bailout, 17.7% of patients with TMPG 0/1/2 did by 48 hours (P =.037). CONCLUSIONS: Impaired tissue level perfusion as assessed by the TMPG and not epicardial coronary blood flow is associated with CK-MB elevation after PCI. These data provide a pathophysiologic link between impaired tissue level perfusion, post-PCI infarction, and adverse clinical outcomes.


Assuntos
Angioplastia Coronária com Balão , Circulação Coronária , Creatina Quinase/metabolismo , Isoenzimas/metabolismo , Infarto do Miocárdio/enzimologia , Reperfusão Miocárdica , Stents , Biomarcadores/sangue , Creatina Quinase/sangue , Creatina Quinase Forma MB , Método Duplo-Cego , Eptifibatida , Feminino , Humanos , Isoenzimas/sangue , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/terapia , Peptídeos/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores
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