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2.
Phytopathology ; 106(11): 1393-1403, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27348344

RESUMO

Populations of the potato and tomato late-blight pathogen Phytophthora infestans are well known for emerging as novel clonal lineages. These successions of dominant clones have historically been named US1 through US24, in order of appearance, since their first characterization using molecular markers. Hypothetically, these lineages can emerge through divergence from other U.S. lineages, recombination among lineages, or as novel, independent lineages originating outside the United States. We tested for the presence of phylogenetic relationships among U.S. lineages using a population of 31 whole-genome sequences, including dominant U.S. clonal lineages as well as available samples from global populations. We analyzed ancestry of the whole mitochondrial genome and samples of nuclear loci, including supercontigs 1.1 and 1.5 as well as several previously characterized coding regions. We found support for a shared ancestry among lineages US11 and US18 from the mitochondrial genome as well as from one nuclear haplotype on each supercontig analyzed. The other nuclear haplotype from each sample assorted independently, indicating an independent ancestry. We found no support for emergence of any other of the U.S. lineages from a common ancestor shared with the other U.S. lineages. Each of the U.S. clonal lineages fit a model where populations of new clonal lineages emerge via migration from a source population that is sexual in nature and potentially located in central Mexico or elsewhere. This work provides novel insights into patterns of emergence of clonal lineages in plant pathogen genomes.


Assuntos
Genoma Mitocondrial/genética , Genômica , Phytophthora infestans/genética , Doenças das Plantas/parasitologia , Solanum lycopersicum/parasitologia , Solanum tuberosum/parasitologia , Evolução Biológica , DNA Mitocondrial/química , DNA Mitocondrial/genética , Haplótipos , Sequenciamento de Nucleotídeos em Larga Escala , Fases de Leitura Aberta/genética , Filogenia , Phytophthora infestans/isolamento & purificação , Análise de Sequência de DNA
3.
Analyst ; 140(5): 1376-90, 2015 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-25465076

RESUMO

Ion Mobility Spectrometry (IMS) is a widely used and 'well-known' technique of ion separation in the gaseous phase based on the differences in ion mobilities under an electric field. All IMS instruments operate with an electric field that provides space separation, but some IMS instruments also operate with a drift gas flow that provides also a temporal separation. In this review we will summarize the current IMS instrumentation. IMS techniques have received an increased interest as new instrumentation and have become available to be coupled with mass spectrometry (MS). For each of the eight types of IMS instruments reviewed it is mentioned whether they can be hyphenated with MS and whether they are commercially available. Finally, out of the described devices, the six most-consolidated ones are compared. The current review article is followed by a companion review article which details the IMS hyphenated techniques (mainly gas chromatography and mass spectrometry) and the factors that make the data from an IMS device change as a function of device parameters and sampling conditions. These reviews will provide the reader with an insightful view of the main characteristics and aspects of the IMS technique.


Assuntos
Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Humanos , Íons
4.
Analyst ; 140(5): 1391-410, 2015 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-25465248

RESUMO

Ion Mobility Spectrometry (IMS) is a widely used and 'well-known' technique of ion separation in the gaseous phase based on the differences of ion mobilities under an electric field. This technique has received increased interest over the last several decades as evidenced by the pace and advances of new IMS devices available. In this review we explore the hyphenated techniques that are used with IMS, specifically mass spectrometry as an identification approach and a multi-capillary column as a pre-separation approach. Also, we will pay special attention to the key figures of merit of the ion mobility spectrum and how data sets are treated, and the influences of the experimental parameters on both conventional drift time IMS (DTIMS) and miniaturized IMS also known as high Field Asymmetric IMS (FAIMS) in the planar configuration. The present review article is preceded by a companion review article which details the current instrumentation and contains the sections that configure both conventional DTIMS and FAIMS devices. These reviews will give the reader an insightful view of the main characteristics and aspects of the IMS technique.


Assuntos
Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Humanos , Íons
5.
Am J Transplant ; 8(2): 355-65, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18093266

RESUMO

Improvements in human immunodeficiency virus (HIV)-associated mortality make it difficult to deny transplantation based upon futility. Outcomes in the current management era are unknown. This is a prospective series of liver or kidney transplant recipients with stable HIV disease. Eleven liver and 18 kidney transplant recipients were followed for a median of 3.4 years (IQR [interquartile range] 2.9-4.9). One- and 3-year liver recipients' survival was 91% and 64%, respectively; kidney recipients' survival was 94%. One- and 3-year liver graft survival was 82% and 64%, respectively; kidney graft survival was 83%. Kidney patient and graft survival were similar to the general transplant population, while liver survival was similar to the older population, based on 1999-2004 transplants in the national database. CD4+ T-cell counts and HIV RNA levels were stable; and there were two opportunistic infections (OI). The 1- and 3-year cumulative incidence (95% confidence intervals [CI]) of rejection episodes for kidney recipients was 52% (28-75%) and 70% (48-92%), respectively. Two-thirds of hepatitis C virus (HCV)-infected patients, but no patient with hepatitis B virus (HBV) infection, recurred. Good transplant and HIV-related outcomes among kidney transplant recipients, and reasonable outcomes among liver recipients suggest that transplantation is an option for selected HIV-infected patients cared for at centers with adequate expertise.


Assuntos
Infecções por HIV/complicações , Transplante de Rim/estatística & dados numéricos , Transplante de Fígado/estatística & dados numéricos , Adulto , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , Cadáver , Feminino , Seguimentos , Rejeição de Enxerto/epidemiologia , Infecções por HIV/tratamento farmacológico , Humanos , Transplante de Rim/imunologia , Transplante de Fígado/imunologia , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Doadores de Tecidos/estatística & dados numéricos , Resultado do Tratamento , Carga Viral
6.
Int J Behav Nutr Phys Act ; 3: 20, 2006 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-16879750

RESUMO

BACKGROUND: Rising obesity and declining physical activity levels are of great concern because of the associated health risks. Many children are left unsupervised after the school day ends, but little is known about the association between unsupervised time and physical activity levels. This paper seeks to determine whether adolescent girls who are without adult supervision after school are more or less active than their peers who have a caregiver at home. METHODS: A random sample of girls from 36 middle schools at 6 field sites across the U.S. was selected during the fall of the 2002-2003 school year to participate in the baseline measurement activities of the Trial of Activity for Adolescent Girls (TAAG). Information was collected using six-day objectively measured physical activity, self-reported physical activity using a three-day recall, and socioeconomic and psychosocial measures. Complete information was available for 1422 out of a total of 1596 respondents.Categorical variables were analyzed using chi square and continuous variables were analyzed by t-tests. The four categories of time alone were compared using a mixed linear model controlling for clustering effects by study center. RESULTS: Girls who spent more time after school (> or = 2 hours per day, > or = 2 days per week) without adult supervision were more active than those with adult supervision (p = 0.01). Girls alone for > or = 2 hours after school, > or = 2 days a week, on average accrue 7.55 minutes more moderate to vigorous physical activity (MVPA) per day than do girls who are supervised (95% confidence interval ([C.I]). These results adjusted for ethnicity, parent's education, participation in the free/reduced lunch program, neighborhood resources, or available transportation. Unsupervised girls (n = 279) did less homework (53.1% vs. 63.3%), spent less time riding in a car or bus (48.0% vs. 56.6%), talked on the phone more (35.5% vs. 21.1%), and watched more television (59.9% vs. 52.6%) than supervised girls (n = 569). However, unsupervised girls also were more likely to be dancing (14.0% vs. 9.3%) and listening to music (20.8% vs. 12.0%) (p < .05). CONCLUSION: Girls in an unsupervised environment engaged in fewer structured activities and did not immediately do their homework, but they were more likely to be physically active than supervised girls. These results may have implications for parents, school, and community agencies as to how to structure activities in order to encourage teenage girls to be more physically active.

7.
J Pak Med Assoc ; 56(6): 267-72, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16827250

RESUMO

OBJECTIVES: To describe the distribution of over weight and body mass index, waist circumference and waist/ hip ratio, correlate obesity measures to coronary heart disease risk factors in comparison to Pakistan National Survey (PNS). METHODS: The Metroville Health Study (MHS) was an urban risk factor reduction intervention study in Metroville Karachi. Base line data was used which was not a random sample. Demographic data including serum cholesterol, glucose, haemoglobin, and blood pressure were collected. RESULTS: In MHS high cholesterol was 16% and 24% in men and women respectively, and 25% had hypertension. Self-reported diabetes was 8%, over-weight/obesity 34% and 49% for men and women, compared to 16% and 25% for PNS, while high risk waist-hip ratio (WHR) was present in 41% and 72% of men and women respectively. Under-weight in Metroville men was 12% and 9% in women, compared to 26% and 27% in PNS. The anthropometry variables were significantly correlated with each other while weight was significantly correlated with TC and waist circumference (WC). CONCLUSION: Obesity was alarmingly prevalent in urban Metroville in comparison to PNS. Cardio Vascular Disease (CVD) risk factors were prevalent in Metroville and TC and WC were significantly correlated with obesity measures. For prevention of increasing CVD in urban communities, targeted programs of intervention are required.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , National Institutes of Health (U.S.) , Adolescente , Adulto , Fatores Etários , Antropometria , Índice de Massa Corporal , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Relações Comunidade-Instituição , Diabetes Mellitus Tipo 2/etiologia , Feminino , Humanos , Hiperlipidemias/epidemiologia , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/epidemiologia , Paquistão/epidemiologia , Prevalência , Fatores de Risco , Estados Unidos , Saúde da População Urbana
8.
J Pak Med Assoc ; 55(8): 333-8, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16164160

RESUMO

OBJECTIVE: To determine the awareness level, blood pressure profile and its correlates in Metroville Health Study and to compare the results with those of Pakistan National Health Survey and National Health and Nutrition Examination Survey of USA. METHODS: Sample consisted of 400 households of Metroville, included after informed consent. Demographic data was collected and Blood pressure, Cholesterol, Blood Glucose, Height and weight were measured. Obesity was calculated as BMI. The results were compared with those of the Pakistan National Health Survey and National Health and Nutrition Examination Survey of USA. RESULTS: For both sexes and all age groups, hypertension was more prevalent in MHS than Pakistan National Health Survey (PNHS) and U.S. MHS hypertensives were more likely to be aware of and treated for their condition than hypertensives of PNHS, but less likely than U.S. hypertensives. Systolic and diastolic blood pressure (DBP) rose with increased age in all three populations. Blood pressure also rose with increased body mass index (BMI) in MHS as well as PNHS and NHANES, with little differences in the degree of rise among them. A one-kg/Height (in m approximately) increment in BMI was associated with a 0.40-0.67 mmHg increment in systolic pressure in men and a 0.56-0.74 mmHg increment in women. The main difference between USA and two Pakistani surveys was the level of DBP, which was significantly higher in Pakistani Surveys than NHANES, for both men and women. CONCLUSIONS: The prevalence of Hypertension in Metroville was high. It showed a quantitative relationship to increasing age and BMI. Hypertension and obesity were the major public health problems in the lower middle class community of Metroville. It is recommended that awareness should be increased and preventive measures implemented.


Assuntos
Pressão Sanguínea , Hipertensão/epidemiologia , Classe Social , Saúde da População Urbana/estatística & dados numéricos , Adolescente , Adulto , Idoso , Feminino , Humanos , Hipertensão/economia , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Prevalência , Fatores Socioeconômicos , Estados Unidos/epidemiologia
9.
Asia Pac J Public Health ; 15(1): 30-6, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14620495

RESUMO

The Metroville Health Study aimed to reduce consumption of total cooking fats by 33%, salt by 25% and replace ghee with vegetable oil in a lower middle class urban community in Pakistan. Households (n=403) were randomly assigned to Intervention and Control groups. A baseline screening collected data on CVD risk factors, knowledge and attitudes and household consumption of cooking fats and salt. Intervention households received information about CVD and regular visits by social workers who measured cooking fats and salt and counselled cooks on the goals of intervention. Two years later, 291 households were re-screened. Intervention households reduced consumption of fats and salt compared to differences were total fat, 48% (p<0.0001); ghee, 37% (p=0.005); vegetable oil, 33% (p=0.0001); and salt, 41% (p=0.011). Household visits by trained social workers were effective in achieving reductions in consumption of cooking fat and salt in a lower class urban community.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Comportamento de Redução do Risco , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/etiologia , Culinária/métodos , Gorduras na Dieta/administração & dosagem , Gorduras na Dieta/efeitos adversos , Comportamento Alimentar , Feminino , Promoção da Saúde/métodos , Humanos , Masculino , Paquistão , Fatores de Risco
10.
Schizophr Bull ; 29(1): 73-80, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12908662

RESUMO

The design of the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) schizophrenia and Alzheimer's disease studies pose several statistical challenges, including issues related to performing multiple comparisons, defining effectiveness outcomes, and collecting and analyzing data from a design with multiple outcome-driven re-randomizations. We discuss the CATIE strategy for addressing many hypotheses within the context of one clinical trial while controlling the overall type I error rate. We provide motivation for the use of two effectiveness outcomes: time to all-cause discontinuation and composite endpoints that combine outcomes from multiple domains, such as efficacy, safety, cost-effectiveness, and quality of life. Methods for statistical analysis of an outcome-driven re-randomization trial are compared and evaluated. We describe analysis within each phase, analysis based on the first randomization or treatment algorithms, and repeated measures modeling. Finally, strategies are described for designing an electronic data collection system for trials with repeated outcome-driven re-randomizations.


Assuntos
Antipsicóticos/uso terapêutico , Processamento Eletrônico de Dados/estatística & dados numéricos , Avaliação de Processos e Resultados em Cuidados de Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto , Esquizofrenia/tratamento farmacológico , Algoritmos , Antipsicóticos/economia , Análise Custo-Benefício , Humanos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto/economia , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Esquizofrenia/economia
11.
Nutr Metab Cardiovasc Dis ; 12(3): 118-26, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12325468

RESUMO

BACKGROUND AND AIM: Increasing cardiovascular disease (CVD) mortality in the People's Republic of China (PRC) led to the 1981 establishment of the PRC-USA Study of Cardiovascular and Cardiopulmonary Epidemiology which, among other objectives, is concerned with the correlates of CVD morbidity and mortality in Chinese populations among other objectives. This report describes changes in total cholesterol (TC) levels in four PRC populations from 1983 to 1993 and identifies factors related to the changes. METHODS AND RESULTS: Population screenings carried out in 1983-1984, 1987-1988 and 1993-1994 involved the collection of demographic data, specimens (including blood), medical history and physical examination data. The data from cohort and independent samples were used to assess TC changes in urban and rural men and women over the decade, with and without adjustment for age and body mass index (BMI) changes. For Guangzhou men and women, the cohort analyses (aged 35-54 at baseline) showed increases in TC of 10-20 mg/dL after adjustment for age and changes in BMI; the independent sample analyses (aged 35-44) also showed higher average TC levels in 1993-1994 than in 1983-1984. For the Beijing cohorts, the results showed decreases in TC during the decade in men, an increase in TC in urban women and no change in rural women; the independent sample analyses indicated declines in TC for Beijing men and women. Possible reasons for the Guangzhou TC increases are economic growth, and dietary and BMI changes. The mean age-adjusted BMI significantly increased (5-10%) over the 10-year period in all of the studied groups. CONCLUSIONS: TC increased 10-20 mg/dL in Guangzhou men and women, probably as a result of socioeconomic development during the decade. The inconsistent patterns of TC changes in Beijing require further study.


Assuntos
Doenças Cardiovasculares/epidemiologia , Colesterol/sangue , Lipídeos/sangue , Fenômenos Fisiológicos da Nutrição , Adulto , Distribuição por Idade , Índice de Massa Corporal , Doenças Cardiovasculares/etiologia , China/epidemiologia , Colesterol/análise , Intervalos de Confiança , Estudos Transversais , Feminino , Humanos , Incidência , Lipídeos/análise , Masculino , Pessoa de Meia-Idade , Valores de Referência , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , População Rural , Estudos de Amostragem , Distribuição por Sexo , População Urbana
12.
Br J Ophthalmol ; 86(9): 1002-6, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12185127

RESUMO

BACKGROUND/AIM: Although routine ophthalmoscopy is recommended in the evaluation of people with hypertension, the prognostic significance of retinopathy is unknown. The purpose of this study is to determine if hypertensive retinopathy predicts coronary heart disease (CHD). METHODS: A prospective cohort study involving 560 hypertensive, hyperlipidaemic, middle aged men enrolled in the Lipid Research Clinic's Coronary Primary Prevention Trial. Signs of hypertensive retinopathy (generalised and focal arteriolar narrowing, arteriovenous nicking, widened arteriolar light reflex, retinal haemorrhage and exudates, microaneurysms, and disc swelling) were evaluated by direct funduscopy during a baseline examination by study physicians. Incident CHD events were ascertained from hospital records, necropsy reports, and death certificates, and reviewed by a masked panel of cardiologists. RESULTS: There were 51 definite CHD events (definite CHD deaths or myocardial infarctions) during a median follow up of 7.8 years. After adjusting for age, blood pressure, electrocardiographic manifestations of left ventricular hypertrophy, cholesterol levels and treatment, glucose and creatinine levels, and smoking status in proportional hazards analysis, the presence of hypertensive retinopathy predicted a doubling of the risk of definite CHD events (relative risk 2.1; 95% confidence interval (CI) 1.0 to 4.2 ). The presence of either generalised or focal arteriolar narrowing predicted almost a tripling of the risk (relative risk 2.9; 95% CI 1.3 to 6.2). Associations were similar for stage 1 hypertension (systolic and diastolic blood pressures of 140-159 and 90-99 mm Hg, respectively) and for other CHD end points. CONCLUSION: Hypertensive retinopathy predicts CHD in high risk men, independent of blood pressure and CHD risk factors. The data support the concept that retinal microvascular changes are markers of blood pressure damage and may be useful in risk stratification and in the tailoring of hypertension treatment decisions.


Assuntos
Doença das Coronárias/complicações , Hipertensão/complicações , Doenças Retinianas/complicações , Doença das Coronárias/fisiopatologia , Humanos , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/fisiopatologia , Doenças Retinianas/fisiopatologia , Fatores de Risco
13.
J Food Prot ; 64(8): 1199-205, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11510660

RESUMO

The U.S. Department of Agriculture and the Food and Drug Administration have issued temperature requirements to help consumers cook beef patty products that are free of pathogens. Verification of end-point temperature (EPT) is needed in cooked meat products due to concerns over outbreaks of Escherichia coli O157:H7. Acid phosphatase (ACP) activity was studied as a potential method for determination of EPT in ground beef patties cooked nonfrozen, patties frozen 7 days and thawed at room temperature 4 h in a refrigerator or by microwave, and patties made from ground beef frozen in store packages, then thawed in a refrigerator overnight. Pressed-out meat juices were analyzed from patties (n = 314) cooked to 57.2 degrees C (135 degrees F). 65.6 degrees C (150 degrees F), 71.1 degrees C (160 degrees F), and 79.4 degrees C (175 degrees F) target EPTs. Expressed meat juice and internal meat patty color decreased in redness as EPT increased. Freezing whole packs with slow refrigerator or room temperature thawing caused significantly greater loss of redness in expressed cooked meat juice than did other handling methods. Log10 ACP had a significant linear (R2 = 0.99) response to EPT. Results show that the 3- to 5-min ACP test could be used to verify EPT in griddle-cooked hamburger patties.


Assuntos
Fosfatase Ácida/metabolismo , Culinária/métodos , Escherichia coli O157/patogenicidade , Manipulação de Alimentos/métodos , Produtos da Carne/normas , Animais , Bovinos , Cor , Qualidade de Produtos para o Consumidor , Surtos de Doenças/prevenção & controle , Manipulação de Alimentos/normas , Temperatura Alta , Humanos , Produtos da Carne/microbiologia , Controle de Qualidade
14.
Biophys J ; 81(2): 1163-70, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11463657

RESUMO

Previous measurements of transmembrane potential using the electrochromic probe di-8-ANEPPS have used the excitation spectral shift response by alternating excitation between two wavelengths centered at voltage-sensitive portions of the excitation spectrum and recording at a single wavelength near the peak of the emission spectrum. Recently, the emission spectral shift associated with the change in transmembrane potential has been used for continuous membrane potential monitoring. To characterize this form of the electrochromic response from di-8-ANEPPS, we have obtained fluorescence signals from single cells in response to step changes in transmembrane potentials set with a patch electrode, using single wavelength excitation near the peak of the dye absorption spectrum. Fluorescence changes at two wavelengths near voltage-sensitive portions of the emission spectrum and shifts in the complete emission spectrum were determined for emission from plasma membrane and internal membrane. We found that the fluorescence ratio from either dual-wavelength recordings, or from opposite sides of the emission spectrum, varied linearly with the amplitude of the transmembrane potential step between -80 and +60 mV. Voltage dependence of difference spectra exhibit a crossover point near the peak of the emission spectra with approximately equal gain and loss of fluorescence intensity on each side of the spectrum and equal response amplitude for depolarization and hyperpolarization. These results are consistent with an electrochromic mechanism of action and demonstrate how the emission spectral shift response can be used to measure the transmembrane potential in single cells.


Assuntos
Membrana Celular/química , Membrana Celular/metabolismo , Potenciais da Membrana , Linhagem Celular , Corantes Fluorescentes/metabolismo , Humanos , Técnicas de Patch-Clamp , Compostos de Piridínio/metabolismo , Espectrometria de Fluorescência
15.
Int J Epidemiol ; 30(2): 371-9, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11369745

RESUMO

BACKGROUND: The association between coronary heart disease (CHD) and social status has differed among societies in strength and direction. As years of schooling is a major determinant of socioeconomic status and dyslipidaemia a major CHD determinant, the purpose of this investigation is to estimate the association of years of schooling with plasma lipids and lipoproteins among samples from five countries representing different cultures, socio-political systems and stages of economic development. METHODS: Men and women from Chinese, Polish, Russian, Israeli and US samples were studied. Years of schooling were analysed both as a multi-category ordinal variable and divided into two strata: less than the equivalent of high school and greater than or equal to high school equivalence. Fasting plasma cholesterol, low density lipoprotein (LDL) cholesterol, high density lipoprotein (HDL) cholesterol and triglycerides were compared across years of schooling strata within each country. Lipid levels were computed unadjusted and then adjusted for age and lipid risk factor variables. RESULTS: Total cholesterol, LDL cholesterol, and triglycerides varied directly with years of schooling in Chinese, Polish and Russian men, and in contrast varied inversely with years of schooling among US white men. The HDL cholesterol varied inversely with years of schooling for Chinese, Polish, and Russian men, but varied directly with years of schooling among US white men. The lipid differences between men of high versus low years of schooling were not explained by age, body mass index, smoking, alcohol consumption or blood pressure medication use. Findings were less consistent for women and for Israelis and US blacks of both genders. CONCLUSIONS: Lipid and lipoprotein levels consistent with atherogenicity varied directly with years of schooling in Chinese, Polish, and Russian samples. Opposite trends were present in US whites. These findings are consistent with a hypothesized influence of social status on CHD risk differing among populations in relation to stages in societal economic development.


Assuntos
Colesterol/sangue , Educação , Triglicerídeos/sangue , Ásia , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Comparação Transcultural , Europa Oriental , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Risco , Estados Unidos
16.
Brain Res Cogn Brain Res ; 11(2): 213-26, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11275483

RESUMO

We identified human brain regions involved in the perception of sad, frightened, happy, angry, and neutral facial expressions using functional magnetic resonance imaging (fMRI). Twenty-one healthy right-handed adult volunteers (11 men, 10 women; aged 18-45; mean age 21.6 years) participated in four separate runs, one for each of the four emotions. Participants viewed blocks of emotionally expressive faces alternating with blocks of neutral faces and scrambled images. In comparison with scrambled images, neutral faces activated the fusiform gyri, the right lateral occipital gyrus, the right superior temporal sulcus, the inferior frontal gyri, and the amygdala/entorhinal cortex. In comparisons of emotional and neutral faces, we found that (1) emotional faces elicit increased activation in a subset of cortical regions involved in neutral face processing and in areas not activated by neutral faces; (2) differences in activation as a function of emotion category were most evident in the frontal lobes; (3) men showed a differential neural response depending upon the emotion expressed but women did not.


Assuntos
Encéfalo/fisiologia , Emoções/fisiologia , Expressão Facial , Imageamento por Ressonância Magnética , Adulto , Comportamento , Mapeamento Encefálico , Feminino , Humanos , Masculino , Estimulação Luminosa
17.
Stat Med ; 20(2): 305-16, 2001 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-11169604

RESUMO

Pathways is a multi-centre school-based trial sponsored by the National Heart, Lung, and Blood Institute testing the efficacy of an obesity prevention intervention in American Indian children. During the study's protocol development, we prepared an analysis plan that accounted for missing data. In this paper, we present a case study of the process we used to decide upon the final analysis plan. The primary endpoint of the Pathways study is a comparison of per cent body fat between treatment and usual care groups at the end of a three-year intervention. Other studies on children and Native Americans have had moderate to large amounts of missing data. As a result we were concerned that missing data in Pathways would affect the type I error rate and power of the test of our primary endpoint. We present results from our evaluation of three alternative procedures in this paper. The first is a multiple imputation procedure in which we replace missing values with resampled values from the observed data. The second is based on the Wilcoxon rank sum test; missing data in the intervention group receive the worst ranks. In the third, we use a multiple imputation procedure and replace missing values with predicted values from a regression equation with the coefficients estimated from observed follow-up data and baseline values. We found that the multiple imputation procedure that replaces missing values with predicted values had the best properties of the procedures we considered. The results from our simulation study showed that, for missing data patterns that are relevant to the Pathways study, this procedure has high power and maintains the type I error rate. Published in 2001 by John Wiley & Sons, Ltd.


Assuntos
Simulação por Computador , Interpretação Estatística de Dados , Estudos Multicêntricos como Assunto/métodos , Obesidade/prevenção & controle , Análise de Variância , Estatura , Peso Corporal , Criança , Impedância Elétrica , Determinação de Ponto Final , Humanos , Indígenas Norte-Americanos , Método de Monte Carlo , Instituições Acadêmicas , Dobras Cutâneas
18.
Org Lett ; 2(17): 2717-9, 2000 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-10990436

RESUMO

[reaction: see text]The structure and relative stereochemistry of the novel silphiperfolane-type sesquiterpene cameroonan-7alpha-ol (1) were confirmed by a total synthesis of (+/-)-1 from 3,3,5-trimethylbicyclo[3.3.0]oct-1(8)-en-2-one (6) by means of a Sakurai reaction with (Z)-crotylsilane, free radical hydrobromination, base-induced cyclization, and LiAlH4 reduction.


Assuntos
Sesquiterpenos/síntese química , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Plantas Medicinais/química , Estereoisomerismo
19.
Int J Obes Relat Metab Disord ; 24(8): 982-8, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10951536

RESUMO

OBJECTIVE: Obesity, as measured by body mass index, is highly prevalent in Native American children, yet there are no valid equations to estimate total body fatness for this population. This study was designed to develop equations to estimate percentage body fat from anthropometry and bioelectrical impedance as a critical part of Pathways, a multi-site study of primary prevention of obesity in Native American children. DESIGN: Percentage fat was estimated from deuterium oxide dilution in 98 Native American children (Pima/Maricopa, Tohono O'odham and White Mountain Apache tribes) between 8 and 11 y of age. The mean fat content (38.4%+/-8. 1%) was calculated assuming the water content of the fat-free body was 76%. Initial independent variables were height, weight, waist circumference, six skinfolds and whole-body resistance and reactance from bioelectrical impedance (BIA). RESULTS: Using all-possible-subsets regressions with the Mallows C (p) criterion, and with age and sex included in each regression model, waist circumference, calf and biceps skinfolds contributed least to the multiple regression analysis. The combination of weight, two skinfolds (any two out of the four best: triceps, suprailiac, subscapular and abdomen) and bioelectrical impedance variables provided excellent predictability. Equations without BIA variables yielded r2 almost as high as those with BIA variables. The recommended equation predicts percentage fat with a root mean square error=3.2% fat and an adjusted r2=0.840. CONCLUSION: The combination of anthropometry and BIA variables can be used to estimate total body fat in field studies of Native American children. The derived equation yields considerably higher percentage fat values than other skinfold equations in children.


Assuntos
Tecido Adiposo/anatomia & histologia , Composição Corporal , Indígenas Norte-Americanos/estatística & dados numéricos , Obesidade/epidemiologia , Obesidade/prevenção & controle , Antropometria , Arizona/epidemiologia , Criança , Proteção da Criança/estatística & dados numéricos , Óxido de Deutério/análise , Impedância Elétrica , Feminino , Humanos , Masculino , Obesidade/etnologia , Valores de Referência , Análise de Regressão , Saliva/química
20.
J Hypertens ; 18(8): 999-1006, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10953989

RESUMO

OBJECTIVE: The purpose of this research is to assess short-term blood pressure change and hypertension incidence, and identify correlates of incident hypertension in the USA and Poland. DESIGN AND METHODS: Population-based samples aged 45-64 years at enrollment from the Atherosclerosis Risk in Communities (ARIC) and the Pol-MONICA studies: including 3777 whites from Minneapolis, Minnesota, USA suburbs (urban), 3635 whites from Washington County, Maryland, USA (semi-rural) and 3109 blacks from Jackson, Mississippi, USA surveyed in 1987-1989 and 1990-1992; and 389 persons from Warsaw, Poland (urban) and 322 from Tarnobrzeg Province, Poland (semi-rural) surveyed in 1987-1988 and 1992-1993. RESULTS: Age-standardized systolic and diastolic blood pressures at both screens were 9-20 and 5-9 mmHg higher in the Polish samples than in US blacks, who had higher levels than US whites. Age-adjusted annual hypertension incidence in both Polish male cohorts (6-8%) was higher than that in US white men (4%) and approaching that of US black men (7%); rates were also higher in Polish female cohorts (8-9%) than in US black women (8%), but nearly twice those in US white women (4%). Factors independently related to hypertension incidence included age, family history, smoking, baseline blood pressures and body mass index, and increase in body mass index and alcohol consumption between screenings. After adjustment for these factors, annualized hypertension incidence was similar in US white and Polish men (2.3 and 2.7%) compared with US black men (3.4%), and in US white and Polish women (1.5 and 1.3%) compared with US black women (3.9%). CONCLUSIONS: Despite substantial differences in blood pressure levels and age-standardized hypertension incidence rates, the differences in incidence between Polish and US white men appear to be explained largely by differences in risk factors for hypertension.


Assuntos
Arteriosclerose/epidemiologia , Doenças Cardiovasculares/epidemiologia , Hipertensão/epidemiologia , Adulto , Envelhecimento/fisiologia , Anti-Hipertensivos/uso terapêutico , Determinação da Pressão Arterial , Coleta de Dados , Feminino , Humanos , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Razão de Chances , Polônia/epidemiologia , Risco , Estados Unidos/epidemiologia
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