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2.
J Acquir Immune Defic Syndr ; 67(4): 357-64, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25202922

RESUMO

BACKGROUND: HIV-1 shedding from the female genital tract is associated with increased sexual and perinatal transmission and has been broadly evaluated in cross-sectional studies. However, few longitudinal studies have evaluated how the immune microenvironment effects shedding. METHODS: Thirty-nine HIV-1-infected women had blood, cervicovaginal lavage, and biopsies of the uterine cervix taken quarterly for up to 5 years. Cytokines/chemokines were quantified by Luminex assay in cervicovaginal lavage, and cellular phenotypes were characterized using immunohistochemistry in cervical biopsies. Comparisons of cytokine/chemokine concentrations and the percent of tissue staining positive for T cells were compared using generalized estimating equations between non-shedding and shedding visits across all women and within a subgroup of women who intermittently shed HIV-1. RESULTS: Genital HIV-1 shedding was more common when plasma HIV-1 was detected. Cytokines associated with cell growth (interleukin-7), Th1 cells/inflammation (interleukin-12p70), and fractalkine were significantly increased at shedding visits compared with non-shedding visits within intermittent shedders and across all subjects. Within intermittent shedders and across all subjects, FOXP3 T cells were significantly decreased at shedding visits. However, there were significant increases in CD8 cells and proportions of CD8FOXP3 T cells associated with HIV-1 shedding. CONCLUSIONS: Within intermittent HIV-1 shedders, decreases in FOXP3 T cells at the shedding visit suggests that local HIV-1 replication leads to CD4 T-cell depletion, with increases in the proportion of CD8FOXP3 cells. HIV-1-infected cell loss may promote a cytokine milieu that maintains cellular homeostasis and increases immune suppressor cells in response to HIV-1 replication in the cervical tissues.


Assuntos
Linfócitos T CD8-Positivos/fisiologia , Quimiocinas/fisiologia , Citocinas/fisiologia , Fatores de Transcrição Forkhead/fisiologia , Genitália Feminina/virologia , Infecções por HIV/virologia , HIV-1/fisiologia , Células Th1/fisiologia , Eliminação de Partículas Virais/fisiologia , Linfócitos T CD8-Positivos/virologia , Quimiocina CX3CL1/fisiologia , Feminino , Homeostase/fisiologia , Humanos , Interleucina-7/fisiologia , Subpopulações de Linfócitos T/fisiologia , Células Th1/virologia , Carga Viral/fisiologia
3.
Pediatr Infect Dis J ; 33(4): 401-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24378937

RESUMO

BACKGROUND: Infants born to HIV-1 infected mothers may have increased risk for tuberculosis (TB), but the prevalence of TB infection in this population is undefined. In contrast to tuberculin skin tests that are confounded by recent bacille Calmette-Guérin (BCG) vaccination, TB interferon gamma release assays (IGRAs) do not cross-react with BCG and enable detection of TB infection in infancy. METHODS: In a nested observational cohort of HIV-1 infected Kenyan mothers and their infants, we conducted T-SPOT.TB assays on cryopreserved peripheral blood mononuclear cells from 6-month-old infants without prior active TB. Maternal and infant correlates of infant TB infection were assessed. RESULTS: One hundred and eight-two infants were tested with T-SPOT.TB. Of 128 infants with determinate T-SPOT.TB results, the prevalence of a positive T-SPOT.TB was 10.9% [95% confidence interval (CI): 6.1-17.7%]. All infants were BCG-vaccinated and 7.0% were HIV-1 infected. Positive infant T-SPOT.TB was associated with maternal active TB (odds ratio: 15.5, 95% CI: 1.3-184; P = 0.04) and prolonged infant fever (>1 month) (odds ratio: 18.8, 95% CI: 1.6-223; P = 0.03). CONCLUSIONS: We observed a high prevalence of TB infection in 6-month-old HIV-1 exposed infants. Improved TB detection and prevention are warranted in HIV-1 exposed infants at high risk for active TB disease.


Assuntos
Infecções por HIV/microbiologia , HIV-1 , Tuberculose/virologia , Adulto , Estudos de Coortes , Feminino , Infecções por HIV/sangue , Infecções por HIV/epidemiologia , Humanos , Lactente , Testes de Liberação de Interferon-gama , Quênia/epidemiologia , Leucócitos Mononucleares/microbiologia , Exposição Materna , Mães/estatística & dados numéricos , Tuberculose/sangue , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Adulto Jovem
4.
PLoS One ; 8(10): e76533, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24098523

RESUMO

INTRODUCTION: Rapid tests for rifampicin resistance may be useful for identifying isolates at high risk of drug resistance, including multidrug-resistant TB (MDR-TB). However, choice of diagnostic test and prevalence of rifampicin resistance may both impact a diagnostic strategy for identifying drug resistant-TB. We performed a systematic review to evaluate the performance of WHO-endorsed rapid tests for rifampicin resistance detection. METHODS: We searched MEDLINE, Embase and the Cochrane Library through January 1, 2012. For each rapid test, we determined pooled sensitivity and specificity estimates using a hierarchical random effects model. Predictive values of the tests were determined at different prevalence rates of rifampicin resistance and MDR-TB. RESULTS: We identified 60 publications involving six different tests (INNO-LiPA Rif. TB assay, Genotype MTBDR assay, Genotype MTBDRplus assay, Colorimetric Redox Indicator (CRI) assay, Nitrate Reductase Assay (NRA) and MODS tests): for all tests, negative predictive values were high when rifampicin resistance prevalence was ≤ 30%. However, positive predictive values were considerably reduced for the INNO-LiPA Rif. TB assay, the MTBDRplus assay and MODS when rifampicin resistance prevalence was < 5%. LIMITATIONS: In many studies, it was unclear whether patient selection or index test performance could have introduced bias. In addition, we were unable to evaluate critical concentration thresholds for the colorimetric tests. DISCUSSION: Rapid tests for rifampicin resistance alone cannot accurately predict rifampicin resistance or MDR-TB in areas with a low prevalence of rifampicin resistance. However, in areas with a high prevalence of rifampicin resistance and MDR-TB, these tests may be a valuable component of an MDR-TB management strategy.


Assuntos
Antituberculosos/uso terapêutico , Farmacorresistência Bacteriana Múltipla , Testes de Sensibilidade Microbiana/estatística & dados numéricos , Mycobacterium tuberculosis/efeitos dos fármacos , Rifampina/uso terapêutico , Viés , Humanos , Mycobacterium tuberculosis/patogenicidade , Mycobacterium tuberculosis/fisiologia , Valor Preditivo dos Testes , Kit de Reagentes para Diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/microbiologia
5.
Clin Infect Dis ; 54(8): 1137-44, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22354919

RESUMO

BACKGROUND: Iron supplementation may increase malaria morbidity and mortality, but the effect of naturally occurring variation in iron status on malaria risk is not well studied. METHODS: A total of 785 Tanzanian children living in an area of intense malaria transmission were enrolled at birth, and intensively monitored for parasitemia and illness including malaria for up to 3 years, with an average of 47 blood smears. We assayed plasma samples collected at routine healthy-child visits, and evaluated the impact of iron deficiency (ID) on future malaria outcomes and mortality. RESULTS: ID at routine, well-child visits significantly decreased the odds of subsequent parasitemia (23% decrease, P < .001) and subsequent severe malaria (38% decrease, P = .04). ID was also associated with 60% lower all-cause mortality (P = .04) and 66% lower malaria-associated mortality (P = .11). When sick visits as well as routine healthy-child visits are included in analyses (average of 3 iron status assays/child), ID reduced the prevalence of parasitemia (6.6-fold), hyperparasitemia (24.0-fold), and severe malaria (4.0-fold) at the time of sample collection (all P < .001). CONCLUSIONS: Malaria risk is influenced by physiologic iron status, and therefore iron supplementation may have adverse effects even among children with ID. Future interventional studies should assess whether treatment for ID coupled with effective malaria control can mitigate the risks of iron supplementation for children in areas of malaria transmission.


Assuntos
Deficiências de Ferro , Malária Falciparum/epidemiologia , Feminino , Humanos , Masculino
6.
Nutr Res ; 30(3): 163-70, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20417876

RESUMO

Population-based studies suggest that repetitive cycling of weight loss and regain may be associated with future weight gain. Therefore, to better define the relationship between weight cycling, energy homeostasis, and future weight gain, we examined associations between frequent intentional weight loss and hormonal profiles in postmenopausal women. This cross-sectional study evaluated the relationship between a history of frequent weight loss and biomarkers, including serum glucose, insulin, leptin, and ghrelin, as well as sex steroid hormones. We hypothesized that frequent intentional weight loss would be associated with changes in normal appetite and body weight regulatory hormones, favoring increased appetite and weight gain. One hundred fifty-nine healthy, weight stable, sedentary, overweight, postmenopausal women who had been recruited for an exercise intervention participated in this study. History of intentional weight loss (frequency and magnitude) was assessed by questionnaire. Hormonal assays were performed by radioimmunoassay (insulin, leptin, ghrelin, estrogens, androgens, and dehydroepiandrosterone), chemiluminescence immunoassay (insulin-like growth factor-1), and immunometric assay (sex hormone binding globulin). Analysis of variance and regression analyses were used to investigate the relationship between weight loss history and metabolic hormones. A higher degree of weight cycling, characterized by the frequency of intentionally losing more than 10 lb, was associated with an appetite-stimulating hormonal profile, including higher concentrations of ghrelin (P trend = .04), lower glucose (P trend = .047), and to some extent, lower insulin (P trend = .08). Frequent weight loss was also associated with lower androgen concentrations, including androstenedione (P trend = .02), testosterone (P trend = .04), and free testosterone (P trend = .01). No independent associations between the concentrations of leptin or estrogens and weight cycling were observed. This study suggests that frequent intentional weight loss may affect hormones involved in energy regulation.


Assuntos
Androgênios/sangue , Glicemia/análise , Grelina/sangue , Pós-Menopausa , Redução de Peso/fisiologia , Idoso , Apetite/fisiologia , Índice de Massa Corporal , Estudos Transversais , Desidroepiandrosterona/sangue , Metabolismo Energético , Estrogênios/sangue , Feminino , Homeostase , Humanos , Insulina/sangue , Leptina/sangue , Pessoa de Meia-Idade , Testosterona/sangue , Aumento de Peso/fisiologia
7.
Hum Genet ; 127(2): 163-82, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19859740

RESUMO

Nitric oxide (NO) mediates host resistance to severe malaria and other infectious diseases. NO production and mononuclear cell expression of the NO producing enzyme-inducible nitric oxide synthase (NOS2) have been associated with protection from severe falciparum malaria. The purpose of this study was to identify single nucleotide polymorphisms (SNPs) and haplotypes in the NOS2 promoter, to identify associations of these haplotypes with malaria severity and to test the effects of these polymorphisms on promoter activity. We identified 34 SNPs in the proximal 7.3 kb region of the NOS2 promoter and inferred NOS2 promoter haplotypes based on genotyping 24 of these SNPs in a population of Tanzanian children with and without cerebral malaria. We identified 71 haplotypes; 24 of these haplotypes comprised 82% of the alleles. We determined whether NOS2 promoter haplotypes were associated with malaria severity in two groups of subjects from Dar es Salaam (N = 185 and N = 250) and in an inception cohort of children from Muheza-Tanga, Tanzania (N = 883). We did not find consistent associations of NOS2 promoter haplotypes with malaria severity or malarial anemia, although interpretation of these results was potentially limited by the sample size of each group. Furthermore, cytokine-induced NOS2 promoter activity determined using luciferase reporter constructs containing the proximal 7.3 kb region of the NOS2 promoter and the G-954C or C-1173T SNPs did not differ from NOS2 promoter constructs that lacked these polymorphisms. Taken together, these studies suggest that the relationship between NOS2 promoter polymorphisms and malaria severity is more complex than previously described.


Assuntos
Haplótipos/genética , Malária/genética , Óxido Nítrico Sintase Tipo II/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas/genética , Alelos , Sequência de Bases , Linhagem Celular Tumoral , Criança , Pré-Escolar , Frequência do Gene , Heterogeneidade Genética , Genótipo , Humanos , Lactente , Quênia , Desequilíbrio de Ligação , Malária/patologia , Dados de Sequência Molecular , Mutação , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Índice de Gravidade de Doença , Tanzânia
8.
Cancer Epidemiol Biomarkers Prev ; 18(5): 1524-30, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19423529

RESUMO

BACKGROUND: Epidemiologic studies suggest a reduced risk of breast cancer among women who regularly use aspirin; a plausible mechanism is through aspirin effect on mammographic breast density, a breast cancer risk factor, possibly mediated through aspirin interference with estrogen synthesis. METHODS: In a 2-arm randomized placebo-controlled clinical trial, we evaluated the effects of 6-month administration of 325 mg/day aspirin on total mammographic breast dense area and percent of the mammographic breast image occupied by dense areas (% density) in 143 postmenopausal women. Eligible women, recruited from 2005 to 2007, were healthy, not taking hormone therapy, with elevated mammographic breast density (American College of Radiology Breast Imaging Reporting and Data System density category 2, 3, or 4) within 6 months before enrollment. RESULTS: Women were a mean (SD) 59.5 (5.5) years. Geometric mean baseline percent density was 17.6% (95% confidence interval, 14.8-20.9) in women randomized to aspirin and 19.2% (95% confidence interval, 16.3-22.7) in women randomized to placebo. Percent density decreased in women randomized to aspirin by an absolute 0.8% versus an absolute decrease of 1.2% in controls (P = 0.84). Total breast area and dense area decreased to a similar degree in women assigned to aspirin and in those assigned to placebo, with no statistically significant differences between trial arms. CONCLUSIONS: A single daily administration of adult-dose aspirin for 6 months had no effect on mammographic density in postmenopausal women. If aspirin affects breast cancer risk in postmenopausal women, it may do so through alternative pathways than mammographic breast density.


Assuntos
Aspirina/farmacologia , Neoplasias da Mama/diagnóstico por imagem , Idoso , Aspirina/administração & dosagem , Método Duplo-Cego , Feminino , Humanos , Modelos Lineares , Mamografia , Pessoa de Meia-Idade , Pós-Menopausa , Fatores de Risco
9.
J Clin Oncol ; 27(21): 3437-44, 2009 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-19470939

RESUMO

PURPOSE Chronic inflammation is believed to contribute to the development and progression of breast cancer. Systemic C-reactive protein (CRP) and serum amyloid A (SAA) are measures of low-grade chronic inflammation and potential predictors of cancer survival. PATIENTS AND METHODS We evaluated the relationship between circulating markers of inflammation and breast cancer survival using data from the Health, Eating, Activity, and Lifestyle (HEAL) Study (a multiethnic prospective cohort study of women diagnosed with stage 0 to IIIA breast cancer). Circulating concentrations of CRP and SAA were measured approximately 31 months after diagnosis and tested for associations with disease-free survival (approximately 4.1 years of follow-up) and overall survival (approximately 6.9 years of follow-up) in 734 disease-free breast cancer survivors. Cox proportional hazards models were used with adjustment for potential confounding factors to generate hazard ratios (HRs) and 95% CIs. Results Elevated SAA and CRP were associated with reduced overall survival, regardless of adjustment for age, tumor stage, race, and body mass index (SAA P trend < .0001; CRP P trend = .002). The HRs for SAA and CRP tertiles suggested a threshold effect on survival, rather than a dose-response relationship (highest v lowest tertile: SAA HR = 3.15; 95% CI, 1.73 to 5.65; CRP HR = 2.27; 95% CI, 1.27 to 4.08). Associations were similar and still significant after adjusting for self-reported history of cardiovascular events and censoring cardiovascular disease deaths. Elevated CRP and SAA were also associated with reduced disease-free survival, although these associations were of borderline significance (SAA P trend = .04; CRP P trend = .07). CONCLUSION Circulating SAA and CRP may be important prognostic markers for long-term survival in breast cancer patients, independent of race, tumor stage, and body mass index.


Assuntos
Biomarcadores/sangue , Neoplasias da Mama/mortalidade , Proteína C-Reativa/metabolismo , Prognóstico , Proteína Amiloide A Sérica/metabolismo , Adulto , Neoplasias da Mama/sangue , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Feminino , Humanos , Inflamação/sangue , Inflamação/etiologia , Inflamação/mortalidade , Pessoa de Meia-Idade , Medição de Risco , Resultado do Tratamento , Adulto Jovem
10.
Breast Cancer Res Treat ; 114(1): 155-67, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18401703

RESUMO

INTRODUCTION: Inflammatory status may be an important prognostic factor for breast cancer. Correlates of markers of inflammation in breast cancer survivors have not been thoroughly evaluated. METHODS: Using data from, the Health, Eating, Activity, and Lifestyle (HEAL) Study (a population-based, multiethnic prospective cohort study of female breast cancer patients) we evaluated the associations between circulating markers of inflammation (C-reactive protein [CRP] and serum amyloid A [SAA], measured approximately 31 months after diagnosis) and several demographic, lifestyle, and clinical characteristics in 741 disease-free breast cancer survivors. Analysis of variance and regression methods were used for statistical analyses of log-transformed values of CRP and SAA. RESULTS: After adjusting for age, BMI, ethnicity, and study site, higher concentrations of CRP were associated with increasing concentration of SAA (P-trend < 0.0001), increasing age (P-trend < 0.0001), increasing BMI (P-trend < 0.0001), increasing waist circumference (P-trend < 0.0001), positive history of heart failure (P = 0.0007), decreasing physical activity (P-trend = 0.005), Hispanic ethnicity (P = 0.05 vs. non-Hispanic white), and current smoking (P = 0.03 vs. never smoking). Vitamin E supplementation (P = 0.0005), tamoxifen use (P = 0.008), and radiation treatment (compared to no chemotherapy or radiation; P = 0.04) were associated with reduced CRP. Associations of CRP with clinical characteristics were not significant in the adjusted models. In a multivariate analysis, CRP showed significant associations with waist circumference, BMI, age, history of heart failure, tamoxifen use, and vitamin E supplementation (R (2) = 0.35). Similar, yet fewer, associations were observed for SAA (R (2) = 0.19). CONCLUSIONS: This study highlights important correlates of inflammatory status in breast cancer patients. Our results are consistent with those from similar studies of healthy women.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Mama/sangue , Neoplasias da Mama/epidemiologia , Proteína C-Reativa/análise , Proteína Amiloide A Sérica/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/etnologia , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Estilo de Vida , Pessoa de Meia-Idade , Sobreviventes
11.
J Endocrinol ; 199(1): 51-60, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18614715

RESUMO

Experimental studies and case reports suggest a multifunctional role of leptin in immune function. However, clinical studies of leptin in healthy individuals with a comprehensive assessment of immunity are lacking. This study investigated associations between serum leptin concentrations and multiple biomarkers of cellular immunity and inflammation among 114 healthy postmenopausal, overweight, or obese women. Leptin was measured by RIA. C-reactive protein (CRP) and serum amyloid A (SAA) were measured by nephelometry. Flow cytometry was used to measure natural killer (NK) cell cytotoxicity and to enumerate and phenotype lymphocyte subsets. T-lymphocyte proliferation was assessed in response to phytohemagluttinin, as well as to anti-CD3 antibodies by the flow cytometric cell division tracking method. Multiple linear regression analysis with adjustment for confounding factors and log transformation, where appropriate, was used. Serum leptin concentrations were positively associated with serum CRP, SAA, and interleukin 6 (IL6) (P<0.0001, P=0.01, and P=0.04 respectively), more strongly among women with a body mass index (BMI) <30 kg/m(2). The associations were attenuated after adjustment for measured body composition, yet remained significant for CRP and SAA. No statistically significant associations were observed between leptin and NK cytotoxicity, lymphocyte subpopulations, or T-lymphocyte proliferation. This study fills an important gap in knowledge about the relationship between leptin concentrations and immune function in healthy individuals. Findings support an association between serum leptin and the inflammatory proteins CRP and SAA, which appears to be mediated only partly by adipose tissue. Our study does not support a link between leptin and other immune parameters among overweight or obese, but otherwise healthy postmenopausal women, perhaps because such effects are only present at low or deficient leptin concentrations.


Assuntos
Leptina/sangue , Obesidade/sangue , Obesidade/imunologia , Sobrepeso/sangue , Sobrepeso/imunologia , Pós-Menopausa/sangue , Pós-Menopausa/imunologia , Idoso , Índice de Massa Corporal , Proteína C-Reativa/metabolismo , Proliferação de Células/efeitos dos fármacos , Feminino , Citometria de Fluxo , Humanos , Interleucina-6/sangue , Células Matadoras Naturais/fisiologia , Modelos Lineares , Pessoa de Meia-Idade , Mitógenos/farmacologia , Nefelometria e Turbidimetria , Obesidade/metabolismo , Sobrepeso/metabolismo , Fito-Hemaglutininas/farmacologia , Pós-Menopausa/metabolismo , Radioimunoensaio , Proteína Amiloide A Sérica/metabolismo , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos
12.
Am J Clin Nutr ; 88(1): 133-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18614733

RESUMO

BACKGROUND: Little is known about vitamin D status in breast cancer survivors. This issue is important because vitamin D influences pathways related to carcinogenesis. OBJECTIVE: The objective of this report was to describe and understand vitamin D status in a breast cancer survivor cohort. DESIGN: Data are from the Health, Eating, Activity, and Lifestyle study. With the use of a cross-sectional design, we examined serum concentrations of 25-hydroxyvitamin D [25(OH)D] in 790 breast cancer survivors from western Washington state, New Mexico, and Los Angeles County. Cancer treatment data were obtained from Surveillance, Epidemiology, and End Results registries and medical records. Fasting blood, anthropometry, and lifestyle habits were collected after diagnosis and treatment. We examined distributions of 25(OH)D by race-ethnicity, season, geography, and clinical characteristics. Multivariate regression tested associations between 25(OH)D and stage of disease. RESULTS: Five hundred ninety-seven (75.6%) of the women had low serum 25(OH)D, suggesting vitamin D insufficiency or frank deficiency. The overall mean (+/-SD) was 24.8 +/- 10.4 ng/mL, but it was lower for African Americans (18.1 +/- 8.7 ng/mL) and Hispanics (22.1 +/- 9.2 ng/mL). Women with localized (n = 424) or regional (n = 182) breast cancer had lower serum 25(OH)D than did women with in situ disease (n = 184) (P = 0.05 and P = 0.03, respectively). Multivariate regression models controlled for age, body mass index (in kg/m(2)), race-ethnicity, geography, season, physical activity, diet, and cancer treatments showed that stage of disease independently predicted serum 25(OH)D (P = 0.02). CONCLUSIONS: In these breast cancer survivors, the prevalence of vitamin D insufficiency was high. Clinicians might consider monitoring vitamin D status in breast cancer patients, together with appropriate treatments, if necessary.


Assuntos
Neoplasias da Mama/sangue , Estado Nutricional , Deficiência de Vitamina D/epidemiologia , Vitamina D/sangue , Negro ou Afro-Americano , Índice de Massa Corporal , Estudos de Coortes , Estudos Transversais , Etnicidade , Feminino , Hispânico ou Latino , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Prevalência , Estudos Prospectivos , Fatores de Risco , Vitamina D/análogos & derivados , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/etnologia , População Branca
13.
J Appl Physiol (1985) ; 104(6): 1648-55, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18403448

RESUMO

Cross-sectional studies suggest that moderate physical activity is associated with enhanced resting immune function; however, few randomized controlled trials have investigated this link. We investigated the effect of 12-mo aerobic exercise, relative to stretching control, on in vitro immune function in a randomized, controlled trial of 115 postmenopausal, overweight, or obese sedentary women, aged 50-75 yr. The exercise goal was > or =45 min/day, 5 days/wk. Control women participated in 1 day/wk stretching classes. Immune markers (natural killer cell cytotoxicity, T-lymphocyte proliferation, immune cell counts and phenotypes, and serum immunoglobulins) were assessed at baseline, 3 mo, and 12 mo under strict blood-draw criteria. General estimation equations evaluated intervention effects at 3 and 12 mo, controlling for baseline. Of the 115 women who began the trial, blood samples were available from 109 at 3 mo (95%) and 108 at 12 mo (94%). From baseline to 12 mo, the exercise group participated in 87% of the prescribed physical activity minutes per week and increased maximal O(2) uptake by 13.8%; controls experienced no change in fitness. The main outcomes, natural killer cell cytotoxicity and T-lymphocyte proliferation, did not differ between groups at 3 and 12 mo. Secondary outcome and subgroup (e.g., stratification by baseline categories of body mass index, immune status, C-reactive protein, and age) analyses did not show any clear patterns of association. This 12-mo randomized, controlled trial showed no effect of aerobic exercise on in vitro immune function, despite excellent retention, high adherence, and demonstrable efficacy of the exercise intervention.


Assuntos
Exercício Físico , Imunoglobulinas/sangue , Células Matadoras Naturais/imunologia , Obesidade/imunologia , Sobrepeso/imunologia , Pós-Menopausa/imunologia , Linfócitos T/imunologia , Idoso , Proliferação de Células , Células Cultivadas , Citotoxicidade Imunológica , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Células K562 , Ativação Linfocitária , Contagem de Linfócitos , Pessoa de Meia-Idade , Fenótipo , Fatores de Tempo
14.
Med Sci Sports Exerc ; 40(2): 223-33, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18202581

RESUMO

PURPOSE: The effect of exercise on androgens in middle-aged to older men is poorly understood, and it could have implications for several aspects of health. This analysis was conducted to examine the effects of long-term aerobic exercise on serum sex hormones in middle-aged to older men. METHODS: One hundred two sedentary men, ages 40-75 yr, were randomly assigned to a 12-month exercise intervention or a control group (no change in activity). The combined facility- and home-based exercise program consisted of moderate/vigorous-intensity aerobic activity for 60 min.d(-1), 6 d.wk(-1). Serum concentrations of testosterone, free testosterone, dihydrotestosterone (DHT), 3alpha-androstanediol glucuronide (3alpha-Diol-G), estradiol, free estradiol, and sex hormone-binding globulin (SHBG) were measured at baseline, 3, and 12 months. RESULTS: Exercisers trained a mean of 370 min.wk(-1) (102% of goal), with only two dropouts. Cardiopulmonary fitness (.VO(2max)) increased 10.8% in exercisers and decreased by 1.8% in controls (P < 0.001). DHT increased 14.5% in exercisers versus 1.7% in controls at 3 months (P = 0.04); at 12 months, it remained 8.6% above baseline in exercisers versus a 3.1% decrease in controls (P = 0.03). SHBG increased 14.3% in exercisers versus 5.7% in controls at 3 months (P = 0.04); at 12 months, it remained 8.9% above baseline in exercisers versus 4.0% in controls (P = 0.13). There were significant trends toward increasing DHT and SHBG, with greater increases in .VO(2max) at 3 and 12 months in exercisers. No statistically significant differences were observed for testosterone, free testosterone, 3alpha-Diol-G, estradiol, or free estradiol in exercisers versus controls. CONCLUSIONS: A year-long, moderate-intensity aerobic exercise program increased DHT and SHBG, but it had no effect on other androgens in middle-aged to older men.


Assuntos
Androgênios/análise , Exercício Físico/fisiologia , Adiposidade/fisiologia , Adulto , Idoso , Androgênios/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Washington
15.
J Am Diet Assoc ; 108(1): 125-30, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18155998

RESUMO

Previous studies have shown that sociodemographic characteristics can be determinants of healthful eating. However, health characteristics such as smoking status have not been well studied. The objective of this research, therefore, was to determine predictors of diet quality in postmenopausal women. We included 164 overweight or obese postmenopausal women aged 50 to 75 years living in and around Seattle, WA, and intake, measured by food frequency questionnaire, was used to calculate scores for the Diet Quality Index and Healthy Eating Index. Information on sociodemographic factors and health behaviors was collected by self-administered questionnaire. Body mass index was computed using duplicate measures of height and weight. Percent body fat was measured by dual-energy x-ray absorptiometry. Following data collection, one-way analysis of variance, chi(2), and Pearson correlations were used to compare means of diet quality scores across participant characteristics. We found that predictors of better diet quality in this study population were higher education and former smoking history (compared to never-smokers); there was no evidence for a relationship with income level. Individuals with higher-quality diets were more likely to have lower body mass index or percent body fat. Based on the results of this study, education level and smoking history are predictors of diet quality among overweight and obese postmenopausal women. These findings add to the increasing evidence for targeting public health interventions to individuals with lower education because this group stands to benefit from improved dietary intake. In addition, these results suggest that the timing of smoking cessation is a possible teachable moment for food and nutrition professionals.


Assuntos
Dieta/normas , Escolaridade , Comportamentos Relacionados com a Saúde , Obesidade/psicologia , Sobrepeso/psicologia , Pós-Menopausa , Absorciometria de Fóton , Idoso , Análise de Variância , Composição Corporal/fisiologia , Índice de Massa Corporal , Distribuição de Qui-Quadrado , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Obesidade/etiologia , Sobrepeso/etiologia , Valor Preditivo dos Testes , Saúde Pública , Fumar , Inquéritos e Questionários
16.
Cancer Epidemiol Biomarkers Prev ; 16(11): 2351-6, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18006923

RESUMO

BACKGROUND: Epidemiologic studies provide evidence that exercise is associated with reduced risk of colon cancer. Exercise may exert protective effects on the colon by influencing prostaglandin production. We hypothesized that an exercise intervention would decrease prostaglandin E(2) concentrations and increase prostaglandin F(2alpha) in colon biopsies compared with controls. METHODS: A 12-month randomized controlled trial testing the effects of exercise on colon mucosal prostaglandin concentrations was conducted in men (n=95) and women (n=89). The exercise intervention included moderate-to-vigorous aerobic activity, 60 min/d, 6 days/wk versus controls. Prostaglandin E(2) and F(2alpha) concentrations were measured in colon biopsies using an enzyme-linked immunoassay at baseline and at 12 months to assess changes in mean concentration for each group. RESULTS: Baseline colon prostaglandin E(2) and F(2alpha) concentrations were not correlated with age, race, education, family history of colon cancer, previous polyps, body size, diet, smoking, nonsteroidal antiinflammatory drug use, metabolic factors, or sex hormone levels. For both men and women, the exercise and control groups showed no change in mean prostaglandin E(2) or F(2alpha) between the baseline and 12-month biopsies. There was no difference in mean prostaglandin concentrations between exercisers and controls when exercisers were grouped by level of intervention adherence. Results were not modified by baseline age, body mass index, percentage of body fat, nonsteroidal antiinflammatory drug use, history of adenomatous polyps, or family history of colon cancer. CONCLUSION: A 12-month moderate-to-vigorous intensity aerobic exercise intervention did not result in significant changes in colon mucosal prostaglandin concentrations.


Assuntos
Colo Sigmoide/metabolismo , Dinoprosta/metabolismo , Dinoprostona/metabolismo , Exercício Físico/fisiologia , Mucosa Intestinal/metabolismo , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Am J Clin Nutr ; 86(5): 1445-55, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17991658

RESUMO

BACKGROUND: The link between poor nutritional status and impaired immune function is well established; however, most studies have focused on individual nutrients instead of overall dietary patterns. OBJECTIVE: Our objective was to investigate associations between 3 indexes of overall diet quality [the Diet Quality Index (DQI), the DQI including supplementary calcium (DQI-Ca), and the Healthy Eating Index (HEI)] and biomarkers of inflammation and immunity. DESIGN: This cross-sectional study included 110 overweight or obese postmenopausal women. Dietary intake measured by food-frequency questionnaire was used to calculate diet quality scores. C-reactive protein (CRP) and serum amyloid A (SAA) were measured by latex-enhanced nephelometry. Flow cytometry was used to measure natural killer (NK) cell cytotoxicity and to enumerate and phenotype lymphocyte subsets. T lymphocyte proliferation was assessed by (3)H-thymidine incorporation as well as by the carboxyfluorescein-succinimidyl ester method of cell division tracking. Multivariable-adjusted linear regression analysis was used to investigate associations between diet quality scores and markers of inflammation and immune function. RESULTS: Higher diet quality was associated with increased proportions of cytotoxic and decreased proportions of helper T lymphocytes. CRP and SAA concentrations were higher among women with a lower-quality diet; these associations became nonsignificant after adjustment for body mass index or percentage body fat. We observed limited evidence for an association between healthy eating patterns and greater lymphocyte proliferation and no evidence for an association with NK cell cytotoxicity. CONCLUSION: Our results provide limited evidence that healthy eating patterns contribute to enhanced immune function and reduced inflammation in overweight and obese postmenopausal women.


Assuntos
Dieta , Imunidade , Inflamação/prevenção & controle , Obesidade/imunologia , Sobrepeso/imunologia , Pós-Menopausa/imunologia , Idoso , Proteína C-Reativa/análise , Estudos Transversais , Feminino , Humanos , Células Matadoras Naturais/imunologia , Ativação Linfocitária , Contagem de Linfócitos , Pessoa de Meia-Idade , Proteína Amiloide A Sérica/análise
18.
Cancer Epidemiol Biomarkers Prev ; 16(9): 1767-74, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17855695

RESUMO

BACKGROUND: Cellular proliferation and apoptosis (cell death) are highly regulated in the colon as insufficient apoptosis may lead to polyps and cancer. Physical activity decreases risk of colon cancer in observational studies, but the biological basis is not well defined. The objective of this study is to examine the effects of a 12-month aerobic exercise program on expression of proteins that promote (Bax) or inhibit (Bcl-2) apoptosis in colon crypts. METHODS: Two hundred two sedentary participants, 40 to 75 years, were randomly assigned to moderate-to-vigorous intensity exercise for 60 min per day, 6 days per week for 12 months, or usual lifestyle. Colon crypt samples were obtained at baseline and 12 months. Bcl-2 and Bax expression was measured by immunohistochemistry. RESULTS: Bax density at the bottom of crypts increased in male exercisers versus controls (+0.87 versus -0.18; P = 0.05), whereas the ratio of Bcl-2 to Bax at the bottom and middle of crypts decreased as aerobic fitness (VO(2)max) increased (P trend = 0.02 and 0.05, respectively). In female exercisers, Bax density in the middle of crypts decreased (-0.36 versus +0.69; P = 0.03) and Bcl-2 to Bax ratio at the top of crypts increased versus controls (+0.46 versus -0.85; P = 0.03). Bax density in the middle of crypts also decreased as minutes per week of exercise increased (P trend = 0.03). CONCLUSIONS: A 12-month exercise intervention resulted in greater expression of proteins that promote apoptosis at the bottom of colon crypts in men and decreased expression of proteins that promote apoptosis at the middle and top of colon crypts in women. The difference in effect by gender and location of observed changes warrants further study.


Assuntos
Apoptose , Colo/metabolismo , Exercício Físico , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteína X Associada a bcl-2/biossíntese , Adulto , Idoso , Colo/patologia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Neoplasias do Colo/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Fatores de Tempo
19.
Obesity (Silver Spring) ; 15(6): 1496-512, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17557987

RESUMO

OBJECTIVES: The effect of national exercise recommendations on adiposity is unknown and may differ by sex. We examined long-term effects of aerobic exercise on adiposity in women and men. RESEARCH METHODS AND PROCEDURES: This was a 12-month randomized, controlled clinical trial testing exercise effect on weight and body composition in men (N = 102) and women (N = 100). Sedentary/unfit persons, 40 to 75 years old, were recruited through physician practices and media. The intervention was facility- and home-based moderate-to-vigorous intensity aerobic activity, 60 min/d, 6 days/wk vs. controls (no intervention). RESULTS: Exercisers exercised a mean 370 min/wk (men) and 295 min/wk (women), and seven dropped the intervention. Exercisers lost weight (women, -1.4 vs. +0.7 kg in controls, p = 0.008; men, -1.8 vs. -0.1 kg in controls, p = 0.03), BMI (women, -0.6 vs. +0.3 kg/m(2) in controls, p = 0.006; men, -0.5 kg/m(2) vs. no change in controls, p = 0.03), waist circumference (women, -1.4 vs. +2.2 cm in controls, p < 0.001; men, -3.3 vs. -0.4 cm in controls, p = 0.003), and total fat mass (women, -1.9 vs. +0.2 kg in controls, p = 0.001; men, -3.0 vs. +0.2 kg in controls, p < 0.001). Exercisers with greater increases in pedometer-measured steps per day had greater decreases in weight, BMI, body fat, and intra-abdominal fat (all p trend < 0.05 in both men and women). Similar trends were observed for increased minutes per day of exercise and for increases in maximal oxygen consumption. DISCUSSION: These data support the U.S. Department of Agriculture and Institute of Medicine guidelines of 60 min/d of moderate-to-vigorous physical activity.


Assuntos
Tecido Adiposo , Peso Corporal , Exercício Físico/fisiologia , Adulto , Fatores Etários , Idoso , Algoritmos , Composição Corporal , Distribuição da Gordura Corporal , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Caracteres Sexuais , Método Simples-Cego
20.
Cancer Epidemiol Biomarkers Prev ; 16(5): 895-9, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17507612

RESUMO

Prolactin is associated with an increased risk of postmenopausal breast cancer; however, few modifiable factors are known to reduce prolactin concentrations. Therefore, we examined the effect of a 12-month moderate-intensity exercise intervention on serum prolactin concentrations as a secondary end point (primary end points were estrogens and androgens). We randomly assigned 173 postmenopausal women who were sedentary, overweight (body mass index >24 kg/m(2), body fat >33%), ages 50 to 75 years, and not using hormone therapy to an exercise intervention or stretching control group. The intervention was facility- and home-based (45 min, 5 days/wk moderate-intensity sports/recreational exercise). One hundred and seventy (98%) women completed the study. Prolactin concentrations were similar at baseline (P = 0.25, geometric mean exercisers = 6.9 and controls = 7.5 ng/mL). Overall, the intervention was not associated with changes in prolactin concentrations between exercisers and controls at 3 months (P = 0.46) or 12 months (P = 0.29). The intervention effect did not vary by baseline age, body mass index, parity, or change in percent body fat during the intervention. Among exercisers, there was a significant difference in prolactin concentrations by change in fitness (VO(2)max) between baseline and 12 months. Exercisers whose VO(2)max changed by <5% had a 5% increase in prolactin concentrations, whereas those who increased their VO(2)max by 5% to 15% and >15% had a 11% (P = 0.03) and 7% (P = 0.01) decrease in prolactin concentrations, respectively. Although the exercise intervention had little effect on prolactin concentrations overall, increasing physical fitness was associated with reduced prolactin concentrations among postmenopausal women.


Assuntos
Neoplasias da Mama/prevenção & controle , Exercício Físico/fisiologia , Pós-Menopausa/fisiologia , Prolactina/sangue , Idoso , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sobrepeso , Pós-Menopausa/sangue
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