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2.
J Hum Hypertens ; 31(7): 462-473, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28205551

RESUMO

Measurement error in assessment of sodium and potassium intake obscures associations with health outcomes. The level of this error in a diverse US Hispanic/Latino population is unknown. We investigated the measurement error in self-reported dietary intake of sodium and potassium and examined differences by background (Central American, Cuban, Dominican, Mexican, Puerto Rican and South American). In 2010-2012, we studied 447 participants aged 18-74 years from four communities (Miami, Bronx, Chicago and San Diego), obtaining objective 24-h urinary sodium and potassium excretion measures. Self-report was captured from two interviewer-administered 24-h dietary recalls. Twenty percent of the sample repeated the study. We examined bias in self-reported sodium and potassium from diet and the association of mismeasurement with participant characteristics. Linear regression relating self-report with objective measures was used to develop calibration equations. Self-report underestimated sodium intake by 19.8% and 20.8% and potassium intake by 1.3% and 4.6% in men and women, respectively. Sodium intake underestimation varied by Hispanic/Latino background (P<0.05) and was associated with higher body mass index (BMI). Potassium intake underestimation was associated with higher BMI, lower restaurant score (indicating lower consumption of foods prepared away from home and/or eaten outside the home) and supplement use. The R2 was 19.7% and 25.0% for the sodium and potassium calibration models, respectively, increasing to 59.5 and 61.7% after adjusting for within-person variability in each biomarker. These calibration equations, corrected for subject-specific reporting error, have the potential to reduce bias in diet-disease associations within this largest cohort of Hispanics in the United States.


Assuntos
Potássio na Dieta/urina , Autorrelato , Sódio na Dieta/urina , Adulto , Idoso , Biomarcadores/urina , Calibragem , Estudos de Coortes , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
3.
Public Health Nutr ; 19(18): 3256-3264, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27339078

RESUMO

OBJECTIVE: Measurement error in self-reported total sugars intake may obscure associations between sugars consumption and health outcomes, and the sum of 24 h urinary sucrose and fructose may serve as a predictive biomarker of total sugars intake. DESIGN: The Study of Latinos: Nutrition & Physical Activity Assessment Study (SOLNAS) was an ancillary study to the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) cohort. Doubly labelled water and 24 h urinary sucrose and fructose were used as biomarkers of energy and sugars intake, respectively. Participants' diets were assessed by up to three 24 h recalls (88 % had two or more recalls). Procedures were repeated approximately 6 months after the initial visit among a subset of ninety-six participants. SETTING: Four centres (Bronx, NY; Chicago, IL; Miami, FL; San Diego, CA) across the USA. SUBJECTS: Men and women (n 477) aged 18-74 years. RESULTS: The geometric mean of total sugars was 167·5 (95 % CI 154·4, 181·7) g/d for the biomarker-predicted and 90·6 (95 % CI 87·6, 93·6) g/d for the self-reported total sugars intake. Self-reported total sugars intake was not correlated with biomarker-predicted sugars intake (r=-0·06, P=0·20, n 450). Among the reliability sample (n 90), the reproducibility coefficient was 0·59 for biomarker-predicted and 0·20 for self-reported total sugars intake. CONCLUSIONS: Possible explanations for the lack of association between biomarker-predicted and self-reported sugars intake include measurement error in self-reported diet, high intra-individual variability in sugars intake, and/or urinary sucrose and fructose may not be a suitable proxy for total sugars intake in this study population.


Assuntos
Inquéritos sobre Dietas , Sacarose Alimentar/administração & dosagem , Hispânico ou Latino , Açúcares/administração & dosagem , Adolescente , Adulto , Idoso , Biomarcadores/urina , Sacarose Alimentar/urina , Ingestão de Energia , Feminino , Frutose/urina , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Autorrelato , Estados Unidos , Adulto Jovem
4.
Eur J Clin Nutr ; 70(1): 47-53, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26014267

RESUMO

BACKGROUND/OBJECTIVES: The relationship between obesity and circulating levels of antioxidants is poorly understood. Most studies that have examined the association of adiposity with blood or tissue concentrations of antioxidant micronutrients have been cross-sectional, and few have compared the associations for indices of overall obesity and central obesity. Our aim was to prospectively examine the longitudinal association of body mass index (BMI), waist circumference (WC), waist circumference-height ratio (WCHtR) and waist-hip ratio (WHR) with major serum antioxidants in a population of postmenopausal women. SUBJECTS/METHODS: We used a subsample of participants in the Women's Health Initiative aged 50-79 years at entry with available fasting blood samples and anthropometric measurements obtained at multiple time points over 12.8 years of follow-up (N=2672). Blood samples were used to measure α-carotene, ß-carotene, ß-cryptoxanthin, lutein+zeaxanthin, α-tocopherol, γ-tocopherol and retinol at baseline, and at years 1, 3 and 6. We used mixed-effects linear regression analyses to examine associations between anthropometric measures and serum antioxidants at baseline and over time, controlling for covariates. RESULTS: In longitudinal analyses, carotenoids, and particularly ß-carotene, were strongly and inversely associated with BMI, WC and WCHtR and less so with WHR. α-Tocopherol showed a strong positive association with WHR but not with other anthropometric measures, whereas γ-tocopherol was positively and strongly associated with BMI, WC, WCHtR and less so with WHR. Retinol was positively associated with WHR. The inverse association of several carotenoids with anthropometric measures was stronger in never and former smokers compared with current smokers and in women without the metabolic syndrome. The inverse association of carotenoids with obesity measures may reflect reduced micronutrient concentrations owing to inflammation associated with obesity. CONCLUSIONS: In the present study, the strongest observed associations between anthropometric variables and micronutrients were an inverse association of WC with serum ß-carotene and a positive association of WC with γ-tocopherol.


Assuntos
Adiposidade , Antioxidantes/metabolismo , Obesidade Abdominal/sangue , Obesidade/sangue , Circunferência da Cintura , beta Caroteno/sangue , gama-Tocoferol/sangue , Tecido Adiposo , Idoso , Índice de Massa Corporal , Feminino , Humanos , Estudos Longitudinais , Síndrome Metabólica/sangue , Pessoa de Meia-Idade , Estado Nutricional , Obesidade/etiologia , Obesidade Abdominal/etiologia , Pós-Menopausa , Estudos Prospectivos , Fatores de Risco , Fumar/sangue , Vitamina A/sangue , Relação Cintura-Quadril
5.
Artigo em Inglês | MEDLINE | ID: mdl-24580224

RESUMO

We use an analog of nanoindentation on a colloidal glass to elucidate the incipient plastic deformation of glasses. By tracking the motion of the individual particles in three dimensions, we visualize the strain field and glass structure during the emerging deformation. At the onset of flow, we observe a power-law distribution of strain indicating strongly correlated deformation, and reflecting a critical state of the glass. At later stages, the strain acquires a Gaussian distribution, indicating that plastic events become uncorrelated. Investigation of the glass structure using both static and dynamic measures shows a weak correlation between the structure and the emerging strain distribution. These results indicate that the onset of plasticity is governed by strong power-law correlations of strain, weakly biased by the heterogeneous glass structure.


Assuntos
Coloides/química , Vidro/química , Testes de Dureza/métodos , Microscopia/métodos , Refratometria/métodos , Módulo de Elasticidade , Dureza , Teste de Materiais/métodos , Estresse Mecânico , Resistência à Tração
6.
Sci Rep ; 3: 1064, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23323208

RESUMO

Glasses are lucrative engineering materials owing to their superior mechanical properties such as high strength and large elastic strain. A central question concerns incipient plasticity - the onset of permanent deformation - that is central to their relaxation, aging, yield and fracture. Here, we use an analogue of nano-indentation performed on a colloidal glass to obtain direct images of the incipient plasticity, allowing us to elucidate the onset of permanent deformation. We visualize the microscopic strain by following distorted nearest neighbor configurations, and observe a surprising hierarchical structure of deformation: at the onset of irreversible deformation, the strain acquires a robust fractal structure, and we measure its fractal dimension. These results give direct evidence that the onset of permanent deformation has the hallmarks of a critical point, in agreement with recent theoretical works.

7.
Phys Rev Lett ; 104(7): 074301, 2010 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-20366888

RESUMO

Under appropriate conditions, a column of viscous liquid falling onto a rigid surface undergoes a buckling instability. Here we show experimentally and theoretically that liquid buckling exhibits a hitherto unsuspected complexity involving three different modes-viscous, gravitational, and inertial-depending on how the viscous forces that resist bending of the column are balanced. We also find that the nonlinear evolution of the buckling exhibits a surprising multistability with three distinct states: steady stagnation flow, "liquid rope coiling," and a new state in which the column simultaneously folds periodically and rotates about a vertical axis. The transitions among these states are subcritical, leading to a complex phase diagram in which different combinations of states coexist in different regions of the parameter space.

8.
East Mediterr Health J ; 15(6): 1449-54, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20218137

RESUMO

This study determined the percentiles of systolic and diastolic blood pressure and theABSTRACT This study determined the percentiles of systolic and diastolic blood pressure and the prevalence of hypertension among 789 primary-school children aged 7-12 years in the city of Eghbalieh, Islamic Republic of Iran. Mean systolic and diastolic blood pressure increased with increasing age in both sexes. There was no significant difference between mean systolic pressure in boys and girls overall, but a significant difference was found between boys and girls in 3 age groups. The prevalence of systolic and diastolic hypertension overall was 6.5% and 12.8% respectively. The mean systolic and diastolic blood pressure of boys and girls in all age groups were significantly lower than the Second Task Force on Blood Pressure Control in Children scale.


Assuntos
Pressão Sanguínea , Hipertensão/epidemiologia , Distribuição por Idade , Determinação da Pressão Arterial , Criança , Diástole , Feminino , Humanos , Hipertensão/diagnóstico , Irã (Geográfico)/epidemiologia , Masculino , Programas de Rastreamento , Vigilância da População , Prevalência , Valores de Referência , Distribuição por Sexo , Estudantes/estatística & dados numéricos , Sístole , Saúde da População Urbana/estatística & dados numéricos
9.
(East. Mediterr. health j).
em Inglês | WHO IRIS | ID: who-117784

RESUMO

This study determined the percentiles of systolic and diastolic blood pressure and the prevalence of hypertension among 789 primary-school children aged 7-12 years in the city of Eghbalieh, Islamic Republic of Iran. Mean systolic and diastolic blood pressure increased with increasing age in both sexes. There was no significant difference between mean systolic pressure in boys and girls overall, but a significant difference was found between boys and girls in 3 age groups. The prevalence of systolic and diastolic hypertension overall was 6.5% and 12.8% respectively. The mean systolic and diastolic blood pressure of boys and girls in all age groups were significantly lower than the Second Task Force on Blood Pressure Control in Children scale


Assuntos
Hipertensão , Prevalência , Valores de Referência , Estudantes , Instituições Acadêmicas , Pressão Sanguínea
10.
J Am Diet Assoc ; 96(3): 252-6, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8613659

RESUMO

OBJECTIVE: This study was designed to identify determinants of body size perceptions and their relationship to dietary behavior in a multiethnic group of women. DESIGN: A single interview consisting of the Massara and Stunkard body image cards (1979) and questionnaires on sociocultural background, anthropometry, and dieting history were administered to volunteers from the staff of a hospital. SUBJECTS: The sample was a convenience sample of 186 women representing a range of staff positions recruited from Methodist Hospital in Brooklyn, NY; 174 completed the study. Data on 150 women are presented in this article. RESULTS: Height and weight-for-height were stronger predictors of accuracy of perceived body size than ethnicity. Tall, slight women were more likely to overestimate and short, heavy women were more likely to underestimate actual body size. Ethnicity had an interactive effect with height as taller European Americans were more likely to perceive their body size as larger than actual compared with Afro-Caribbeans and African Americans. Women with a history of dieting were more likely to overestimate their size and to view it as different from what is perceived as attractive to others. APPLICATIONS/CONCLUSIONS: Based on the results, we conclude that body size is a stronger predictor of accuracy of perceived body size than ethnicity; and dieters overestimate their body size and believe it to be heavier than their social group would prefer.


Assuntos
Constituição Corporal , Imagem Corporal , Dieta , Etnicidade , Recursos Humanos em Hospital , Negro ou Afro-Americano , População Negra , Região do Caribe/etnologia , Dieta Redutora , Europa (Continente)/etnologia , Feminino , Humanos , Itália/etnologia , Porto Rico/etnologia , Autoimagem , Estados Unidos
11.
Int J Biol Macromol ; 15(2): 125-9, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8485104

RESUMO

Ring opened analogues of adenine nucleosides substituted at the ninth adenine positions, with and without esterification (compounds I and II), have been studied kinetically and thermodynamically at various temperatures in order to determine the sites of ring opened analogues. These are deemed to be important for binding to the adenosine deaminase. Adenosine deaminase is found to bind more strongly to compound I than to compound II, therefore compound I is a stronger inhibitor than II, because the position of (5') OH on the ribose moiety decreases the inhibitory strength on the ring opened analogue.


Assuntos
Inibidores de Adenosina Desaminase , Adenosina/análogos & derivados , Adenosina/farmacologia , Adenosina/química , Animais , Ligação Competitiva , Bovinos , Técnicas In Vitro , Cinética , Relação Estrutura-Atividade , Termodinâmica
12.
J Reprod Med ; 30(4): 366-7, 1985 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-4009556

RESUMO

A perforated angular pregnancy, unsuspected and asymptomatic, was diagnosed in a 35-year-old woman during elective pregnancy termination in the first trimester. The pregnancy, along with free blood in the abdomen, was found when laparoscopy and then laparotomy were performed for suspected uterine perforation during suction and curettage. Cornual resection and salpingectomy were performed.


Assuntos
Aborto Induzido/efeitos adversos , Gravidez Ectópica , Ruptura Uterina/etiologia , Adulto , Feminino , Humanos , Complicações Intraoperatórias/etiologia , Gravidez
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