Jair Aparecido de Oliveira

Níveis de prática de atividade física habitual em adolescentes

A novel add/drop optical filter providing arbitrary channel arrangements between two input WDM signals and two output WDM signals is presented. The device consists of two WGRs connected by a plurality of 2x2 optical switches and 3 db coupling devices in each WGR branch. Through use of the inventive device, the second of the two input WDM signals can be added to the transmission path, while the second of the two output WDM signals is dropped. The added and dropped signals are of the same frequency, but can carry different information. The same circuit can also be used as a 2x2 wavelength-space switch for WDM signals. In both cases N2 channel arrangements between the two outputs are possible when the two input signals each support N channels.

Fatores de risco cardiovasculares em adolescentes: indicadores biológicos e comportamentais

OBJECTIVE To provide descriptive information and investigate to what extent behavioral risk factors for cardiovascular diseases are associated with biological risk factors in the young population. METHODS The sample included 452 adolescents (246 girls and 206 boys) between 15 and 18 years of age selected in a high school in the city of Londrina, Paraná. Risk factors of a behavioral nature were analyzed as regards insufficient physical activity, excessive intake of fat and cholesterol and smoking. As biological risk factor indicators we used overweight, high arterial pressure levels, and adverse concentration of serum lipids and lipoproteins. RESULTS Approximately 20% of the girls and 16% of the boys presented at least one biological risk factor for development of cardiovascular diseases. Overweight was significantly associated with excessive intake of fats, while elevated arterial pressure was related to sedentary lifestyle and smoking. Excessive intake of fat and cholesterol indicated increased risk of undesirable concentrations of serum lipids and lipoproteins. The risk associated with altered blood pressure and serum lipids and lipoprotein was increased two-fold in smokers when compared with nonsmokers. CONCLUSION The results reinforce the need for interventions targeted at the adoption of a healthy lifestyle, including the regular practice of physical exercise, appropriate dietary patterns, and abstention from smoking as of an early age.

Distribuição centrípeta da gordura corporal, sobrepeso e aptidão cardiorrespiratória: associação com sensibilidade insulínica e alterações metabólicas

The purpose of this paper was to investigate associations between the centripetal distribution of the body fat and serum lipid-lipoproteins, blood pressure and the index Homa-IR of insulin resistance, adjusting for indicators of overweight and cardiorespiratory fitness. Eighty-nine voluntaries were analyzed (44 men and 45 women). The centripetal distribution of the body fat was analyzed through waist circumference (CC) and the overweight by the body mass index (BMI). The cardiorespiratory fitness was followed by the estimate VO(2)max by test of walking. After adjusted for BMI values were found significant coefficient of correlation between CC and levels of blood pressure and ApoB in men, and between CC and index Homa-IR and triglycerides in women. After adjusted for VO(2)max values were verified significant correlations between CC and ApoB and index Homa-IR in men, and between CC and index Homa-IR in women. In conclusion, depending on the sex, the quantity and distribution of the body fat can present different actions in the insulin resistance and associated dysfunctions. The cardiorespiratory fitness per se seems not to contribute on the minimization of the association between the centripetal distribution of the body fat and the index Homa-IR; but presents a considerable impact on the association between the centripetal distribution of the body fat and the lipid metabolism and the levels of blood pressure, mainly in men.

Uso de tabaco e perfil lipídico-lipoprotéico plasmático em adolescentes

OBJECTIVE: To analyze the impact of tobacco use on plasma lipid lipoprotein profile in representative sample of adolescents. METHODS: A sample of 452 subjects (246 girls and 206 boys) 15 to 18 years old were included in the study. Each participant completed a structured and self-administered questionnaire concerning tobacco use. Plasma lipid-lipoprotein concentrations were measured by standard procedures. Differences between mean values were evaluated by analysis of covariance, controlling for saturated fat and cholesterol intake. Odds ratio was used to estimate the relative risk of the smokers being classified with an undesirable level of a plasma lipidlipoprotein parameter. RESULTS: The proportion of smokers was 20.9% for boys and 15.4% for girls. The average consumption of cigarettes per day was 9.2 ± 4.7 for boys and 5.6 ± 3.1 for girls. When compared with non-smokers, boy and girl smokers showed a significantly higher serum levels of total cholesterol, LDL-cholesterol, triglycerides and apolipoprotein B100, and significantly lower serum levels of HDL-cholesterol. Adolescent smokers tended to show a two-fold higher risk of altered lipid-lipoprotein levels than non-smokers. CONCLUSION: The present data could imply that intervention promoting a healthy lifestyle, including non smoking, should start at an early age to prevent or delay development of atherosclerotic lesions and ultimately to minimize the appearance of premature coronary heart disease in adults.

Dispêndio energético diário e níveis de lipídeos-lipoproteínas plasmáticos em adolescentes

O objetivo do estudo foi analisar o impacto da pratica habitual de atividade fisica, mediante estimativas do dispendio energetico diario (DEdiario), no perfil lipidico-lipoproteico plasmatico em amostra representativa de adolescentes. A amostra foi constituida por 452 sujeitos (246 mocas e 206 rapazes) com idade entre 15 e 18 anos. As concentracoes de lipideos-lipoproteinas plasmaticas foram estabelecidas por procedimentos laboratoriais. As informacoes acerca da pratica habitual de atividade fisica foram obtidas por intermedio de instrumento retrospectivo de auto-recordacao. Estabeleceram-se estimativas quanto ao DEDiario com base no custo calorico associado ao tipo e a duracao das atividades registradas pelos adolescentes. A amostra foi estratificada em tres grupos de pratica habitual de atividade fisica: os menos ativos, 75o percentil do DEdiario, e tambem pontos de corte para um perfil lipidico-lipoproteico de risco aterogenico. Os resultados da analise de co-variância, controlando a participacao do indice de massa corporal, mostraram que as concentracoes de HDL-C foram significativamente diferentes de acordo com os grupos crescentes de DEdiario em mocas (p = 0,009) e em rapazes (p = 0,010), porem, o comportamento de variacao dos valores observados foi diferente nos dois sexos. A analise de regressao logistica indicou que o risco relativo para menores valores de HDL-C foi duas vezes maior entre os adolescentes menos ativos em comparacao com os mais ativos. Em ambos os sexos, as concentracoes de colesterol total, LDL-C e triglicerideos nao apresentaram diferencas significativas entre os grupos de DEdiario. Em conclusao, a pratica habitual de atividade fisica mais intensa e o maior DEdiario estao associados com mais elevadas concentracoes de HDL-C em adolescentes de ambos os sexos, independentemente das variacoes do peso corporal. As associacoes entre DEdiario e os outros componentes plasmaticos de lipideos-lipoproteinas tratados no presente estudo foram fracas e inconsistentes.

Prevalence of dyslipidemia in adolescents: Comparison between definitions

INTRODUCTION The indiscriminate use of different diagnostic criteria for the definition of dyslipidemia may result in inaccurate interpretations, which could compromise diagnosis and therefore the therapeutic and prophylactic actions to be taken. OBJECTIVE To analyze possible differences in prevalence rates of dyslipidemia in adolescents based on three diagnostic definitions. METHODS A cross-sectional study was conducted of a representative sample of Brazilian adolescents between 11 and 16 years of age. Blood samples were collected from 1000 students (423 boys and 577 girls) to determine fasting total cholesterol (TC), HDL and LDL cholesterol, and triglycerides (TG). The prevalence of dyslipidemia was established according to three definitions: those of the National Cholesterol Education Program (NCEP), the Brazilian Society of Cardiology (BSC), and the National Health and Nutrition Examination Survey (NHANES). RESULTS Significant differences (p<0.01) were found between the diagnostic criteria for TC (BSC 38.3%; NCEP 11.2%; NHANES 4.8%), HDL cholesterol (BSC 30.0%; NCEP 15.8% NHANES 18.4%), LDL cholesterol (BSC and NCEP 10.8% and NHANES 5.9%), and TG (BSC and NCEP 4.7% and NHANES 1.3%). The overall prevalence of dyslipidemia was 61% (BSC), 28.6% (NCEP) and 24.2% (NHANES). Agreement rates varied significantly (kappa 0.15-0.90). CONCLUSIONS Although a high prevalence of dyslipidemia was observed in this study regardless of the diagnostic criteria used, the wide variation in rates highlights the need to establish a single definition with appropriate discriminatory power for adolescents.