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1.
Anesth Analg ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38530905
2.
J Infect Dis ; 215(9): 1376-1385, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28199679

RESUMO

Background: It is important to identify vaccine-induced immune responses that predict the preventative efficacy of a human immunodeficiency virus (HIV)-1 vaccine. We assessed T-cell response markers as correlates of risk in the HIV Vaccine Trials Network (HVTN) 505 HIV-1 vaccine efficacy trial. Methods: 2504 participants were randomized to DNA/rAd5 vaccine or placebo, administered at weeks 0, 4, 8, and 24. Peripheral blood mononuclear cells were obtained at week 26 from all 25 primary endpoint vaccine cases and 125 matched vaccine controls, and stimulated with vaccine-insert-matched peptides. Primary variables were total HIV-1-specific CD4+ T-cell magnitude and Env-specific CD4+ polyfunctionality. Four secondary variables were also assessed. Immune responses were evaluated as predictors of HIV-1 infection among vaccinees using Cox proportional hazards models. Machine learning analyses identified immune response combinations best predicting HIV-1 infection. Results: We observed an unexpectedly strong inverse correlation between Env-specific CD8+ immune response magnitude and HIV-1 infection risk (hazard ratio [HR] = 0.18 per SD increment; P = .04) and between Env-specific CD8+ polyfunctionality and infection risk (HR = 0.34 per SD increment; P < .01). Conclusions: Further research is needed to determine if these immune responses are predictors of vaccine efficacy or markers of natural resistance to HIV-1 infection.


Assuntos
Vacinas contra a AIDS/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , Vacinas contra a AIDS/administração & dosagem , Adenoviridae/genética , Análise de Variância , Biologia Computacional , Citocinas/imunologia , Vetores Genéticos , Infecções por HIV/prevenção & controle , Humanos , Aprendizado de Máquina , Risco
3.
J Virol ; 83(8): 3719-33, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19176632

RESUMO

Characterization of the immune responses induced in the initial stages of human immunodeficiency virus type 1 (HIV-1) infection is of critical importance for an understanding of early viral pathogenesis and prophylactic vaccine design. Here, we used sequential plasma samples collected during the eclipse and exponential viral expansion phases from subjects acquiring HIV-1 (or, for comparison, hepatitis B virus [HBV]or hepatitis C virus [HCV]) to determine the nature and kinetics of the earliest systemic elevations in cytokine and chemokine levels in each infection. Plasma viremia was quantitated over time, and levels of 30 cytokines and chemokines were measured using Luminex-based multiplex assays and enzyme-linked immunosorbent assays. The increase in plasma viremia in acute HIV-1 infection was found to be associated with elevations in plasma levels of multiple cytokines and chemokines, including rapid and transient elevations in alpha interferon (IFN-alpha) and interleukin-15 (IL-15) levels; a large increase in inducible protein 10 (IP-10) levels; rapid and more-sustained increases in tumor necrosis factor alpha and monocyte chemotactic protein 1 levels; more slowly initiated elevations in levels of additional proinflammatory factors including IL-6, IL-8, IL-18, and IFN-gamma; and a late-peaking increase in levels of the immunoregulatory cytokine IL-10. Notably, there was comparatively little perturbation in plasma cytokine levels during the same phase of HBV infection and a delayed response of more intermediate magnitude in acute HCV infection, indicating that the rapid activation of a striking systemic cytokine cascade is not a prerequisite for viral clearance (which occurs in a majority of HBV-infected individuals). The intense early cytokine storm in acute HIV-1 infection may have immunopathological consequences, promoting immune activation, viral replication, and CD4(+) T-cell loss.


Assuntos
Citocinas/biossíntese , HIV-1/imunologia , Hepacivirus/imunologia , Vírus da Hepatite B/imunologia , Viremia , Infecções por HIV/imunologia , Infecções por HIV/virologia , Hepatite B/imunologia , Hepatite B/virologia , Hepatite C/imunologia , Hepatite C/virologia , Humanos , Estudos Longitudinais , Plasma/química , Plasma/virologia
4.
JMIR Res Protoc ; 7(10): e175, 2018 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-30282622

RESUMO

BACKGROUND: Accurate safety monitoring in HIV vaccine trials is vital to eventual licensure and consequent uptake of products. Current practice in preventive vaccine trials, under the HIV Vaccine Trials Network (HVTN), is to capture related side effects in a hardcopy tool. The reconciliation of this tool, 2 weeks after vaccination at the safety visit, is time consuming, laborious, and fraught with error. Unstructured Supplementary Service Data (USSD), commonly used to purchase airtime, has been suggested for collection of safety data in vaccine trials. With saturated access to mobile phones in South Africa, this cheap, accessible tool may improve accuracy and completeness of collected data and prove feasible and acceptable over the hardcopy tool. OBJECTIVE: The objective of our study is to develop and implement a USSD tool for real-time safety data collection that is feasible and acceptable to participants and staff, allowing for a comparison with the hardcopy tool in terms of completeness and accuracy. METHODS: This feasibility study is being conducted at a single study site, the Centre for the AIDS Programme of Research in South Africa eThekwini Clinical Research site, in South Africa. The feasibility study is nested within a parent phase 1/2a preventive HIV vaccine trial (HVTN 108) as an open-label, randomized controlled trial, open to all consenting parent trial participants. Participants are randomly assigned in a 1:1 ratio to the hardcopy or USSD tool, with data collection targeted to the third and fourth injection time points in the parent trial. Online feasibility and acceptability surveys will be completed by staff and participants at the safety visit. We will itemize and compare error rates between the hardcopy tool and the USSD printout and associated source documentation. We hypothesize that the USSD tool will be shown to be feasible and acceptable to staff and participants and to have superior quality and completion rates to the hardcopy tool. RESULTS: The study has received regulatory approval. We have designed and developed the USSD tool to include all the data fields required for reactogenicity reporting. Online feasibility and accessibility surveys in both English and isiZulu have been successfully installed on a tablet. Data collection is complete, but analysis is pending. CONCLUSIONS: Several HIV preventive vaccine trials are active in Southern Africa, making tools to improve efficiencies and minimize error necessary. Our results will help to determine whether the USSD tool can be used in future vaccine studies and can eventually be rolled out. TRIAL REGISTRATION: ClincalTrials.gov NCT02915016; https://clinicaltrials.gov/ct2/show/NCT02915016 (Archived by WebCite at http://www.webcitation.org/71h0cztDM). REGISTERED REPORT IDENTIFIER: RR1-10.2196/9396.

5.
Cancer Res ; 64(23): 8541-9, 2004 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-15574760

RESUMO

In this study, we performed high-resolution array comparative genomic hybridization with an array of 4153 bacterial artificial chromosome clones to assess copy number changes in 44 archival breast cancers. The tumors were flow sorted to exclude non-tumor DNA and increase our ability to detect gene copy number changes. In these tumors, losses were more frequent than gains, and gains in 1q and loss in 16q were the most frequent alterations. We compared gene copy number changes in the tumors based on histologic subtype and estrogen receptor (ER) status, i.e., ER-negative infiltrating ductal carcinoma, ER-positive infiltrating ductal carcinoma, and ER-positive infiltrating lobular carcinoma. We observed a consistent association between loss in regions of 5q and ER-negative infiltrating ductal carcinoma, as well as more frequent loss in 4p16, 8p23, 8p21, 10q25, and 17p11.2 in ER-negative infiltrating ductal carcinoma compared with ER-positive infiltrating ductal carcinoma (adjusted P values < or = 0.05). We also observed high-level amplifications in ER-negative infiltrating ductal carcinoma in regions of 8q24 and 17q12 encompassing the c-myc and c-erbB-2 genes and apparent homozygous deletions in 3p21, 5q33, 8p23, 8p21, 9q34, 16q24, and 19q13. ER-positive infiltrating ductal carcinoma showed a higher frequency of gain in 16p13 and loss in 16q21 than ER-negative infiltrating ductal carcinoma. Correlation analysis highlighted regions of change commonly seen together in ER-negative infiltrating ductal carcinoma. ER-positive infiltrating lobular carcinoma differed from ER-positive infiltrating ductal carcinoma in the frequency of gain in 1q and loss in 11q and showed high-level amplifications in 1q32, 8p23, 11q13, and 11q14. These results indicate that array comparative genomic hybridization can identify significant differences in the genomic alterations between subtypes of breast cancer.


Assuntos
Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Carcinoma Lobular/genética , Adulto , Idoso , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/metabolismo , Carcinoma Lobular/patologia , DNA de Neoplasias/análise , DNA de Neoplasias/genética , Feminino , Citometria de Fluxo , Dosagem de Genes , Humanos , Pessoa de Meia-Idade , Hibridização de Ácido Nucleico , Receptores de Estrogênio/biossíntese , Reprodutibilidade dos Testes
6.
Int J Biostat ; 7(1): 4, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22848187

RESUMO

The problem of covariate measurement error with heteroscedastic measurement error variance is considered. Standard regression calibration assumes that the measurement error has a homoscedastic measurement error variance. An estimator is proposed to correct regression coefficients for covariate measurement error with heteroscedastic variance. Point and interval estimates are derived. Validation data containing the gold standard must be available. This estimator is a closed-form correction of the uncorrected primary regression coefficients, which may be of logistic or Cox proportional hazards model form, and is closely related to the version of regression calibration developed by Rosner et al. (1990). The primary regression model can include multiple covariates measured without error. The use of these estimators is illustrated in two data sets, one taken from occupational epidemiology (the ACE study) and one taken from nutritional epidemiology (the Nurses' Health Study). In both cases, although there was evidence of moderate heteroscedasticity, there was little difference in estimation or inference using this new procedure compared to standard regression calibration. It is shown theoretically that unless the relative risk is large or measurement error severe, standard regression calibration approximations will typically be adequate, even with moderate heteroscedasticity in the measurement error model variance. In a detailed simulation study, standard regression calibration performed either as well as or better than the new estimator. When the disease is rare and the errors normally distributed, or when measurement error is moderate, standard regression calibration remains the method of choice.


Assuntos
Modelos Teóricos , Análise de Regressão , Consumo de Bebidas Alcoólicas/efeitos adversos , Antineoplásicos/efeitos adversos , Neoplasias da Mama/etiologia , Simulação por Computador , Feminino , Humanos , Modelos Biológicos , Exposição Ocupacional/efeitos adversos
7.
Stat Commun Infect Dis ; 3(1)2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23181167

RESUMO

Five preventative HIV vaccine efficacy trials have been conducted over the last 12 years, all of which evaluated vaccine efficacy (VE) to prevent HIV infection for a single vaccine regimen versus placebo. Now that one of these trials has supported partial VE of a prime-boost vaccine regimen, there is interest in conducting efficacy trials that simultaneously evaluate multiple prime-boost vaccine regimens against a shared placebo group in the same geographic region, for accelerating the pace of vaccine development. This article proposes such a design, which has main objectives (1) to evaluate VE of each regimen versus placebo against HIV exposures occurring near the time of the immunizations; (2) to evaluate durability of VE for each vaccine regimen showing reliable evidence for positive VE; (3) to expeditiously evaluate the immune correlates of protection if any vaccine regimen shows reliable evidence for positive VE; and (4) to compare VE among the vaccine regimens. The design uses sequential monitoring for the events of vaccine harm, non-efficacy, and high efficacy, selected to weed out poor vaccines as rapidly as possible while guarding against prematurely weeding out a vaccine that does not confer efficacy until most of the immunizations are received. The evaluation of the design shows that testing multiple vaccine regimens is important for providing a well-powered assessment of the correlation of vaccine-induced immune responses with HIV infection, and is critically important for providing a reasonably powered assessment of the value of identified correlates as surrogate endpoints for HIV infection.

8.
Cancer Res ; 69(19): 7793-802, 2009 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19773449

RESUMO

Androgen deprivation is the mainstay of therapy for progressive prostate cancer. Despite initial and dramatic tumor inhibition, most men eventually fail therapy and die of metastatic castration-resistant (CR) disease. Here, we characterize the profound degree of genomic alteration found in CR tumors using array comparative genomic hybridization (array CGH), gene expression arrays, and fluorescence in situ hybridization (FISH). Bycluster analysis, we show that the similarity of the genomic profiles from primary and metastatic tumors is driven by the patient. Using data adjusted for this similarity, we identify numerous high-frequency alterations in the CR tumors, such as 8p loss and chromosome 7 and 8q gain. By integrating array CGH and expression array data, we reveal genes whose correlated values suggest they are relevant to prostate cancer biology. We find alterations that are significantly associated with the metastases of specific organ sites, and others with CR tumors versus the tumors of patients with localized prostate cancer not treated with androgen deprivation. Within the high-frequency sites of loss in CR metastases, we find an overrepresentation of genes involved in cellular lipid metabolism, including PTEN. Finally, using FISH, we verify the presence of a gene fusion between TMPRSS2 and ERG suggested by chromosome 21 deletions detected by array CGH. We find the fusion in 54% of our CR tumors, and 81% of the fusion-positive tumors contain cells with multiple copies of the fusion. Our investigation lays the foundation for a better understanding of and possible therapeutic targets for CR disease, the poorly responsive and final stage of prostate cancer.


Assuntos
Aberrações Cromossômicas , Neoplasias da Próstata/genética , Neoplasias de Tecidos Moles/genética , Neoplasias de Tecidos Moles/secundário , Idoso , Idoso de 80 Anos ou mais , Análise por Conglomerados , Hibridização Genômica Comparativa , Dosagem de Genes , Perfilação da Expressão Gênica , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Proteínas de Fusão Oncogênica/genética , Orquiectomia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia
9.
Cancer Res ; 68(14): 5599-608, 2008 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-18632612

RESUMO

Disseminated epithelial cells can be isolated from the bone marrow of a far greater fraction of prostate-cancer patients than the fraction of patients who progress to metastatic disease. To provide a better understanding of these cells, we have characterized their genomic alterations. We first present an array comparative genomic hybridization method capable of detecting genomic changes in the small number of disseminated cells (10-20) that can typically be obtained from bone marrow aspirates of prostate-cancer patients. We show multiple regions of copy-number change, including alterations common in prostate cancer, such as 8p loss, 8q gain, and gain encompassing the androgen-receptor gene on Xq, in the disseminated cell pools from 11 metastatic patients. We found fewer and less striking genomic alterations in the 48 pools of disseminated cells from patients with organ-confined disease. However, we identify changes shared by these samples with their corresponding primary tumors and prostate-cancer alterations reported in the literature, evidence that these cells, like those in advanced disease, are disseminated tumor cells (DTC). We also show that DTCs from patients with advanced and localized disease share several abnormalities, including losses containing cell-adhesion genes and alterations reported to associate with progressive disease. These shared alterations might confer the capability to disseminate or establish secondary disease. Overall, the spectrum of genomic deviations is evidence for metastatic capacity in advanced-disease DTCs and for variation in that capacity in DTCs from localized disease. Our analysis lays the foundation for elucidation of the relationship between DTC genomic alterations and progressive prostate cancer.


Assuntos
Regulação Neoplásica da Expressão Gênica , Genoma , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Adesão Celular , Linhagem Celular Tumoral , Mapeamento Cromossômico , Progressão da Doença , Perfilação da Expressão Gênica , Humanos , Hibridização in Situ Fluorescente , Masculino , Modelos Biológicos , Metástase Neoplásica , Hibridização de Ácido Nucleico
10.
Biostatistics ; 6(2): 211-26, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15772101

RESUMO

Array-based comparative genomic hybridization (array-CGH) provides a high-throughput, high-resolution method to measure relative changes in DNA copy number simultaneously at thousands of genomic loci. Typically, these measurements are reported and displayed linearly on chromosome maps, and gains and losses are detected as deviations from normal diploid cells. We propose that one may consider denoising the data to uncover the true copy number changes before drawing inferences on the patterns of aberrations in the samples. Nonparametric techniques are particularly suitable for data denoising as they do not impose a parametric model in finding structures in the data. In this paper, we employ wavelets to denoise the data as wavelets have sound theoretical properties and a fast computational algorithm, and are particularly well suited for handling the abrupt changes seen in array-CGH data. A simulation study shows that denoising data prior to testing can achieve greater power in detecting the aberrant spot than using the raw data without denoising. Finally, we illustrate the method on two array-CGH data sets.


Assuntos
Interpretação Estatística de Dados , Dosagem de Genes , Hibridização de Ácido Nucleico/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Neoplasias da Mama/genética , Aberrações Cromossômicas , Cromossomos Artificiais Bacterianos/genética , Simulação por Computador , DNA de Neoplasias/genética , Feminino , Fibroblastos , Humanos
11.
Birth Defects Res A Clin Mol Teratol ; 67(9): 643-6, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14703787

RESUMO

BACKGROUND: Oralfacial clefting (OFC) disorders require expedient evaluation and treatment to obtain optimal outcome. In Florida, there is a statewide program targeted to the care of infants with OFC. We therefore sought to determine statewide referral and treatment patterns of children born with OFC identified through the Florida Birth Defects Registry. METHODS: Using data for 1996 and 1997 and ICD-9 CM codes 749.00 - 749.25, we identified 539 OFC cases. All cases were matched with the evaluation and treatment records of the statewide Children's Medical Services' (CMS) craniofacial centers (CFC) and cleft palate clinics (CPC). The likelihood of CMS contact was examined with respect to demographic and other descriptive data characterizing the OFC cases. RESULTS: 42% (227/539) of OFC cases were evaluated at or known to the CFC or CPC. Children with cleft lip and palate were more likely to have had contact than were those with cleft lip or cleft palate alone. The CFC and CPC programs were most likely to provide evaluation between age 2 months and 3 years. Of 12 counties with occurrences of more than 15 OFC cases, 2 had significantly lower contact rates, suggesting possible problems in accessibility or reporting of services. CONCLUSIONS: Statewide Birth Defect Registry data can be used in collaboration with statewide treatment programs to gain insight into referral patterns and provision of services. Factors influencing access to services and quality of care, though not addressed by this study, could be prospectively incorporated into such a project.


Assuntos
Anormalidades Múltiplas/epidemiologia , Anormalidades Múltiplas/cirurgia , Fenda Labial/epidemiologia , Fenda Labial/cirurgia , Fissura Palatina/epidemiologia , Fissura Palatina/cirurgia , Hospitais Estaduais , Anormalidades Múltiplas/classificação , Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/etnologia , Anormalidades Múltiplas/etiologia , Povo Asiático , População Negra , Pré-Escolar , Aberrações Cromossômicas/induzido quimicamente , Fenda Labial/classificação , Fenda Labial/diagnóstico , Fenda Labial/etnologia , Fenda Labial/etiologia , Fissura Palatina/classificação , Fissura Palatina/diagnóstico , Fissura Palatina/etnologia , Fissura Palatina/etiologia , Feminino , Florida/epidemiologia , Controle de Formulários e Registros/estatística & dados numéricos , Hispânico ou Latino , Humanos , Lactente , Masculino , Idade Materna , Prontuários Médicos/estatística & dados numéricos , Ilhas do Pacífico/etnologia , Gravidez , Resultado da Gravidez , Prevalência , Encaminhamento e Consulta , Sistema de Registros/estatística & dados numéricos , Estudos Retrospectivos , Razão de Masculinidade , Teratogênicos/toxicidade , População Branca
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