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1.
Genet Med ; 21(7): 1594-1602, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30523342

RESUMO

PURPOSE: The acquisition of pathogenic variants in the TERT promoter (TERTp) region is a mechanism of tumorigenesis. In nonmalignant diseases, TERTp variants have been reported only in patients with idiopathic pulmonary fibrosis (IPF) due to germline variants in telomere biology genes. METHODS: We screened patients with a broad spectrum of telomeropathies (n = 136), their relatives (n = 52), and controls (n = 195) for TERTp variants using a customized massively parallel amplicon-based sequencing assay. RESULTS: Pathogenic -124 and -146 TERTp variants were identified in nine (7%) unrelated patients diagnosed with IPF (28%) or moderate aplastic anemia (4.6%); five of them also presented cirrhosis. Five (10%) relatives were also found with these variants, all harboring a pathogenic germline variant in telomere biology genes. TERTp clone selection did not associate with peripheral blood counts, telomere length, and response to danazol treatment. However, it was specific for patients with telomeropathies, more frequently co-occurring with TERT germline variants and associated with aging. CONCLUSION: We extend the spectrum of nonmalignant diseases associated with pathogenic TERTp variants to marrow failure and liver disease due to inherited telomerase deficiency. Specificity of pathogenic TERTp variants for telomerase dysfunction may help to assess the pathogenicity of unclear constitutional variants in the telomere diseases.


Assuntos
Regiões Promotoras Genéticas , Telomerase/genética , Telômero/patologia , Adolescente , Adulto , Idoso , Anemia Aplástica/genética , Contagem de Células Sanguíneas , Doenças da Medula Óssea/genética , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Fibrose Pulmonar Idiopática/genética , Hepatopatias/genética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Telomerase/deficiência , Adulto Jovem
2.
Blood ; 130(22): 2363-2372, 2017 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-29046282

RESUMO

Clonal hematopoiesis occurs normally, especially with aging, and in the setting of disease, not only in myeloid cancers but in bone marrow failure as well. In cancer, malignant clones are characterized by recurrent somatic mutations in specific sets of genes, but the direct relationship of such mutations to leukemogenesis, when they occur in cells of an apparently healthy older individual or after recovery from immune aplastic anemia, is uncertain. Here we emphasize a view of clonal evolution that stresses natural selection over deterministic ontogeny, and we stress the selective role of the environment of the marrow and organism. Clonal hematopoieses after chemotherapy, in marrow failure, and with aging serve as models. We caution against the overinterpretation of clinical results of genomic testing in the absence of a better understanding of clonal selection and evolution.


Assuntos
Anemia Aplástica/genética , Medula Óssea/patologia , Evolução Clonal , Hematopoese , Leucemia/genética , Síndromes Mielodisplásicas/genética , Envelhecimento , Anemia Aplástica/patologia , Animais , Medula Óssea/metabolismo , Humanos , Leucemia/patologia , Mutação , Síndromes Mielodisplásicas/patologia
3.
Hepatology ; 61(4): 1127-35, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25614962

RESUMO

UNLABELLED: Treatment options for patients with hepatitis C virus (HCV) genotype 3 infection are limited, with the currently approved all-oral regimens requiring 24-week treatment and the addition of ribavirin (RBV). This phase III study (ALLY-3; ClinicalTrials.gov: NCT02032901) evaluated the 12-week regimen of daclatasvir (DCV; pangenotypic nonstructural protein [NS]5A inhibitor) plus sofosbuvir (SOF; pangenotypic NS5B inhibitor) in patients infected with genotype 3. Patients were either treatment naïve (n = 101) or treatment experienced (n = 51) and received DCV 60 mg plus SOF 400 mg once-daily for 12 weeks. Coprimary endpoints were the proportions of treatment-naïve and treatment-experienced patients achieving a sustained virological response (SVR) at post-treatment week 12 (SVR12). SVR12 rates were 90% (91 of 101) and 86% (44 of 51) in treatment-naïve and treatment-experienced patients, respectively; no virological breakthrough was observed, and ≥99% of patients had a virological response (VR) at the end of treatment. SVR12 rates were higher in patients without cirrhosis (96%; 105 of 109) than in those with cirrhosis (63%; 20 of 32). Five of seven patients who previously failed treatment with an SOF-containing regimen and 2 of 2 who previously failed treatment with an alisporivir-containing regimen achieved SVR12. Baseline characteristics, including gender, age, HCV-RNA levels, and interleukin-28B genotype, did not impact virological outcome. DCV plus SOF was well tolerated; there were no adverse events (AEs) leading to discontinuation and only 1 serious AE on-treatment, which was unrelated to study medications. The few treatment-emergent grade 3/4 laboratory abnormalities that were observed were transient. CONCLUSION: A 12-week regimen of DCV plus SOF achieved SVR12 in 96% of patients with genotype 3 infection without cirrhosis and was well tolerated. Additional evaluation to optimize efficacy in genotype 3-infected patients with cirrhosis is underway.


Assuntos
Antivirais/administração & dosagem , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Imidazóis/administração & dosagem , Uridina Monofosfato/análogos & derivados , Administração Oral , Adulto , Idoso , Carbamatos , Quimioterapia Combinada , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Pirrolidinas , Sofosbuvir , Fatores de Tempo , Uridina Monofosfato/administração & dosagem , Valina/análogos & derivados , Adulto Jovem
4.
JAMA ; 304(12): 1358-64, 2010 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-20858879

RESUMO

CONTEXT: Critically short telomeres produce apoptosis, cell senescence, and chromosomal instability in tissue culture and animal models. Variations in telomere length have been reported in severe aplastic anemia but their clinical significance is unknown. OBJECTIVE: To investigate the relationship between telomere length and clinical outcomes in severe aplastic anemia. DESIGN, SETTING, AND PATIENTS: Single institution analysis of 183 patients with severe aplastic anemia who were treated in sequential prospective protocols at the National Institutes of Health from 2000 to 2008. The pretreatment leukocyte age-adjusted telomere length of patients with severe aplastic anemia consecutively enrolled in immunosuppression protocols with antithymocyte globulin plus cyclosporine for correlation with clinical outcomes were analyzed. MAIN OUTCOME MEASURES: Hematologic response, relapse, clonal evolution, and survival. RESULTS: There was no relationship between hematologic response and telomere length with response rates of 56.5% of 46 patients in the first, 54.3% of 46 in the second, 60% of 45 in the third, and 56.5% of 46 in the fourth quartiles. Multivariate analysis demonstrated that telomere length was associated with relapse, clonal evolution, and mortality. Evaluated as a continuous variable, telomere length inversely correlated with the probability of hematologic relapse (hazard ratio [HR], 0.16; 95% confidence interval [CI], 0.03-0.69; P = .01). The probability of clonal evolution was higher in patients in the first quartile (24.5%; 95% CI, 8.7%-37.5%) than in quartiles 2 through 4 (8.4%; 95% CI, 3.2%-13.3%; P = .009), and evolution to monosomy 7 or complex cytogenetics was more common in the first quartile (18.8%; 95% CI, 3.5%-31.6%) [corrected] than in quartiles 2 through 4 (4.5%; 95% CI, 0.5%-8.2%; P = .002) [corrected]. Survival between these 2 groups differed, with 66% (95% CI, 52.9%-82.5%) surviving 6 years in the first quartile compared with 83.8% (95% CI, 77.3%-90.9%) in quartiles 2 through 4 (P = .008). CONCLUSION: In a cohort of patients with severe aplastic anemia receiving immunosuppressive therapy, telomere length was unrelated to response but was associated with risk of relapse, clonal evolution, and overall survival.


Assuntos
Anemia Aplástica/genética , Transformação Celular Neoplásica , Instabilidade Cromossômica , Telômero/ultraestrutura , Adulto , Anemia Aplástica/sangue , Anemia Aplástica/tratamento farmacológico , Anemia Aplástica/patologia , Estudos de Coortes , Feminino , Humanos , Imunossupressores/uso terapêutico , Leucócitos/ultraestrutura , Masculino , Prognóstico , Recidiva , Análise de Sobrevida , Resultado do Tratamento
5.
Cell ; 134(5): 782-92, 2008 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-18775311

RESUMO

Binding of the HIV envelope to the chemokine coreceptors triggers membrane fusion and signal transduction. The fusion process has been well characterized, yet the role of coreceptor signaling remains elusive. Here, we describe a critical function of the chemokine coreceptor signaling in facilitating HIV infection of resting CD4 T cells. We find that static cortical actin in resting T cells represents a restriction and that HIV utilizes the Galphai-dependent signaling from the chemokine coreceptor CXCR4 to activate a cellular actin-depolymerizing factor, cofilin, to overcome this restriction. HIV envelope-mediated cofilin activation and actin dynamics are important for a postentry process that leads to viral nuclear localization. Inhibition of HIV-mediated actin rearrangement markedly diminishes viral latent infection of resting T cells. Conversely, induction of active cofilin greatly facilitates it. These findings shed light on viral exploitation of cellular machinery in resting T cells, where chemokine receptor signaling becomes obligatory.


Assuntos
Actinas/metabolismo , Linfócitos T CD4-Positivos/virologia , Cofilina 1/metabolismo , Proteína gp120 do Envelope de HIV/metabolismo , Receptores CXCR4/metabolismo , Sequência de Aminoácidos , Antígenos CD4 , Células Cultivadas , Cofilina 1/química , HIV , Infecções por HIV , Humanos , Dados de Sequência Molecular , Transdução de Sinais
6.
J Am Coll Nutr ; 26(2): 141-8, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17536125

RESUMO

OBJECTIVE: Clinical and epidemiological studies have reported the beneficial effects of tree nuts and peanuts on serum lipid levels. We studied the effects of consuming 15% of the daily caloric intake in the form of pistachio nuts on the lipid profiles of free-living human subjects with primary, moderate hypercholesterolemia (serum cholesterol greater than 210 mg/dL). METHODS: design: Randomized crossover trial. setting: Outpatient dietary counseling and blood analysis. subjects: 15 subjects with moderate hypercholesterolemia. intervention: Fours weeks of dietary modification with 15% caloric intake from pistachio nuts. MEASURES OF OUTCOME: Endpoints were serum lipid levels of total cholesterol, HDL-C, LDL-C, VLDL-C, triglycerides and apolipoproteins A-1 and B-100. BMI, blood pressure, and nutrient intake (total energy, fat, protein, and fiber) were also measured at baseline, during, and after dietary intervention. RESULTS: No statistically significant differences were observed for total energy or percent of energy from protein, carbohydrate or fat. On the pistachio nut diet, a statistically significant decrease was seen for percent energy from saturated fat (mean difference, -2.7%; 95% CI, -5.4% to -0.08%; p = 0.04). On the pistachio nut diet, statistically significant increases were seen for percent energy from polyunsaturated fat (mean difference, 6.5%; 95% CI, 4.2% to 8.9%; p<.0001) and fiber intake (mean difference, 15 g; 95% CI, 8.4 g to 22 g; p = 0.0003). On the pistachio diet, statistically significant reductions were seen in TC/HDL-C (mean difference, -0.38; 95% CI, -0.57 to -0.19; p = 0.001), LDL-C/HDL-C (mean difference, -0.40; 95% CI, -0.66 to -0.15; p = 0.004), B-100/A-1 (mean difference, -0.11; 95% CI, -0.19 to -0.03; p = 0.009) and a statistically significant increase was seen in HDL-C (mean difference, 2.3; 95% CI, 0.48 to 4.0; p = 0.02). No statistically significant differences were seen for total cholesterol, triglycerides, LDL-C, VLDL-C, apolipoprotein A-1 or apolipoprotein B-100. No changes were observed in BMI or blood pressure. CONCLUSION: A diet consisting of 15% of calories as pistachio nuts (about 2-3 ounces per day) over a four week period can favorably improve some lipid profiles in subjects with moderate hypercholesterolemia and may reduce risk of coronary disease.


Assuntos
Colesterol/sangue , Hipercolesterolemia/dietoterapia , Lipídeos/sangue , Pistacia , Apolipoproteína A-I/sangue , Apolipoproteína B-100/sangue , Pressão Sanguínea , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Doença das Coronárias/sangue , Doença das Coronárias/etiologia , Estudos Cross-Over , Ingestão de Energia , Feminino , Humanos , Hipercolesterolemia/sangue , Hipercolesterolemia/complicações , Masculino , Pessoa de Meia-Idade
8.
Dig Dis Sci ; 49(5): 850-3, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15259508

RESUMO

Recent research suggests an increase in the incidence of hepatocellular carcinoma (HCC) in the United States, which may be related to an upsurge in the sequelae of chronic liver disease from hepatitis C virus. In addition to factors related to the underlying etiology of liver disease, a number of host factors such as age, gender, and ethnic background may be associated with this increased risk. The aim of this study was to evaluate a number of potential risk factors for HCC in patients with cirrhosis. Patients with biopsy proven HCC were identified from our pathology and cancer registry databases. All those without histologic or clinical cirrhosis and non-HCC hepatic malignancies were excluded. Cirrhotic patients without HCC were also selected from the Cleveland Clinic unified transplant database and were designated controls. Extensive clinicodemographic data were obtained from the databases and chart reviews. When available, paraffin-embedded liver biopsy blocks were obtained for HFE gene analysis. Univariate comparisons were made with chi-square and Fisher's exact test and multivariate analysis was carried out with logistic regression. A total of 760 patients were included in this study, 244 documented cases of HCC and 516 cirrhotic controls without HCC. Patients' age (RR = 3.1 [2.6-3.8]; P < 0.0001), male gender (RR = 3.4 [2.3-5.1]; P < 0.0001), African-American ethnicity (RR = 3.1 [1.6-5.8]; P = 0.0005), and other non-Caucasian ethnicity (RR = 6.9 [3.2-14.4]; P < 0.0001) were independently associated with HCC. Restricting the analysis to HCV-related cirrhosis, the same risk factors remained independently associated with HCC: age (decade; RR = 2.3 [1.6-3.4]; P < 0.0001), male gender (RR = 2.9 [1.2-7.0]; P = 0.02), African-American ethnicity (RR = 3.1 [1.3-7.4]; P = 0.009), and other non-Caucasian ethnicity (RR = 15.8 [1.9-134]; P = 0.01). Iron studies did not reveal an increased risk for iron overload or HFE mutation. Male gender, advancing age, and non-Caucasian ethnic background are independently associated with HCC.


Assuntos
Carcinoma Hepatocelular/epidemiologia , Cirrose Hepática/etiologia , Neoplasias Hepáticas/epidemiologia , Adulto , Idoso , Carcinoma Hepatocelular/etiologia , Feminino , Hepatite C/complicações , Humanos , Sobrecarga de Ferro/complicações , Neoplasias Hepáticas/etiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estados Unidos/epidemiologia
9.
Gastroenterology ; 123(3): 745-50, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12198701

RESUMO

BACKGROUND & AIMS: This prospective study evaluates the role of radiological modalities in establishing the diagnosis of nonalcoholic steatohepatitis (NASH). METHODS: Consecutive patients with biopsy-proven nonalcoholic fatty liver disease (NAFLD) were enrolled (2000-2001). Patients with other liver diseases and significant alcohol consumption (>20 g/day) were excluded. Clinicodemographic data were gathered at the time of liver biopsy. Each biopsy specimen was assessed by a hepatopathologist. Each patient underwent a limited abdominal ultrasonography (US), computerized tomography (CT), and magnetic resonance imaging (MRI). Films were interpreted by a radiologist who used a predetermined radiological protocol. Each radiological study was reread by the same radiologist and a second radiologist. RESULTS: Patients with NASH had greater aspartate aminotransferase levels (P = 0.03), greater ferritin levels (P = 0.05), more hepatocyte ballooning (P < 0.0001), and more fibrosis (P = 0.002). None of the radiological features distinguished between NASH and other types of NAFLD. No radiological modality detected the presence of hepatocyte ballooning, Mallory's hyaline, or fibrosis, which are important features in the diagnosis of NASH. The presence of >33% fat on liver biopsy was optimal for detecting steatosis on radiological imaging. CONCLUSIONS: Differences between NASH and nonprogressive NAFLD were not apparent with any radiological modality. Of the pathologic features important for establishing the diagnosis of NASH, only the severity of steatosis was reflected in these radiological modalities. Good intraobserver agreement was evident for each modality (US, CT, and MRI) that was superior to interobserver agreement.


Assuntos
Fígado Gorduroso/diagnóstico , Imageamento por Ressonância Magnética/normas , Tomografia Computadorizada por Raios X/normas , Ultrassonografia/normas , Adulto , Fígado Gorduroso/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Prospectivos
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