Effects of low birth weight in 8- to 13-year-old children: implications in endothelial function and uric acid levels.

Low birth weight has been associated with an increased incidence of adult cardiovascular disease. Endothelial dysfunction and high levels of serum uric acid are associated with hypertension. In this study, we have determined whether uric acid is related to blood pressure and vascular function in children with low birth weight. We evaluated vascular function using high-resolution ultrasound, blood pressure, and uric acid levels in 78 children (35 girls, 43 boys, aged 8 to 13 years). Increasing levels of uric acid and systolic blood pressure were observed in children with low birth weight. Birth weight was inversely associated with both systolic blood pressure and uric acid; on the other hand, uric acid levels were directly correlated with systolic blood pressure in children of the entire cohort. Low birth weight was associated with reduced flow-mediated dilation (r=0.427, P<0.001). Because the children with low birth weight had elevated uric acid as well as higher systolic blood pressure levels, we evaluated the correlation between these variables. In the low birth weight group, multiple regression analysis revealed that uric acid (beta=-2.886; SE=1.393; P=0.040) had a graded inverse relationship with flow-mediated dilation, which was not affected in a model adjusting for race and gender. We conclude that children with a history of low birth weight show impaired endothelial function and increased blood pressure and uric acid levels. These findings may be early expressions of vascular compromise, contributing to susceptibility to disease in adult life.

[Endothelial function of normotensive adolescents with no risk factors for arterial hypertension]. / Função endotelial de adolescentes normotensos sem fatores de risco para hipertensão arterial.

OBJECTIVE: To define standards for normal endothelial function in adolescents by high-resolution ultrasound measurement of endothelium-dependent vascular dilatation. METHODS: This was a cross-sectional, descriptive, observational study and part of the thematic project "Clinical Study of Growth, Behavior, Arterial Hypertension, Obesity and Oral Health" (ECCCHOS) that was developed by the Discipline of Nutrition at the Universidade Federal de São Paulo. Thirty-one adolescents, eight male and twenty-three female, with no risk factors for systemic arterial hypertension were selected from 1,420 secondary school students. The students were daytime pupils at a school in the southeastern district of the city of São Paulo, the capital of São Paulo state, located in the Southeast region of Brazil. All results are presented in the form of means with standard deviations and percentiles. RESULTS: For male students, endothelium-dependant dilation 90 seconds after the cuff was released was 20.9+/-6.7% [mean +/-1 standard deviation] with a 10th percentile of 12.5 and for females these figures were 18.8+/-12.9% with a 10th percentile of 6.6%. Values for the whole group of subjects were 19.3+/-11.7% and 6.7%, respectively. CONCLUSION: Endothelium-dependant vascular dilation of 6.7%, after 90 seconds, which corresponds to the 10th percentile, can be considered the lower limit of normality for this age group. Knowledge of this limit is important for the diagnosis of endothelium dysfunction that appears before cardiovascular disease.

Função endotelial de adolescentes normotensos sem fatores de risco para hipertensão arterial / Endothelial function of normotensive adolescents with no risk factors for arterial hypertension

OBJETIVO: Definir padrões de normalidade da função endotelial de adolescentes através de avaliação ultra-sonográfica da dilatação vascular dependente do endotélio. MÉTODOS: Estudo descritivo observacional de corte transversal, parte do projeto temático "Estudos Clínicos de Crescimento, Comportamento, Hipertensão Arterial, Obesidade e Saúde Bucal", de sigla ECCCHOS, desenvolvido na Disciplina de Nutrologia da Universidade Federal de São Paulo - Escola Paulista de Medicina. Foram selecionados 31 adolescentes, sendo oito do sexo masculino e 23 do feminino, sem fatores de risco conhecidos para hipertensão arterial sistêmica, entre 1.420 alunos de uma escola de ensino médio da cidade de São Paulo, capital do estado de São Paulo, situado no Sudeste do Brasil. Para apresentação de todos os resultados, utilizaram-se as médias, desvios padrão e percentis. RESULTADOS: A dilatação vascular dependente do endotélio 90 segundos pós-liberação do manguito foi de 20,9±6,7 por cento [média mais ou menos 1 desvio padrão (DP)] e o 10° percentil ficou em 12,5 por cento no sexo masculino e de 18,8±12,9 por cento DP e o 10° percentil em 6,6 por cento no sexo feminino. Os valores no grupo todo foram de 19,3±11,7 por cento e 6,7 por cento, respectivamente. CONCLUSÃO: O 10° percentil (6,7 por cento) da curva de distribuição dos valores de dilatação vascular dependente do endotélio, em adolescentes do presente estudo, pode ser considerado como limite inferior da normalidade. O conhecimento desse limite é importante para o diagnóstico de disfunções endoteliais que aparecem antes das doenças cardiovasculares.

Diagnostic value of attenuation measurements of the kidney on unenhanced helical CT of obstructive ureterolithiasis.

OBJECTIVE: The objective of this study was to assess the diagnostic value of attenuation measurements of the kidney on unenhanced helical CT in patients with obstructive ureterolithiasis. MATERIALS AND METHODS: Consecutive unenhanced helical CT scans of patients referred for acute unilateral renal colic were retrospectively reviewed. Patients with CT evidence of other urinary system diseases were excluded. Included scans (n = 145) were assessed for ureteral stone and secondary signs of obstruction such as unilateral collecting system or ureteral dilatation, perinephric stranding, and periureteral edema. Renal attenuation in Hounsfield units was measured in the upper, middle, and lower portions of the parenchyma, and a mean value was determined for each kidney. RESULTS: Ureteral stones were present in 76 patients. Renal attenuation on the side with lithiasis was lower than on the opposite kidney: 27.2 +/- 3.9 H vs 32.6 +/- 3.4 H (p < 0.001). Attenuation differences between kidneys were higher for patients with ureterolithiasis: 5.4 +/- 3.2 H (range, -3.3 to 13.0 H) versus 1.2 +/- 1.0 H (range, 0-4.7 H) (p < 0.001). An attenuation difference between kidneys greater than or equal to 5.0 H had 61% sensitivity, 100% specificity, 100% positive predictive value, 69% negative predictive value, and 79% accuracy for diagnosis of ureteral lithiasis. CONCLUSION: Attenuation difference between kidneys greater than or equal to 5.0 H was a valuable sign and had diagnostic performance similar to other secondary signs of obstructive ureterolithiasis. Furthermore, attenuation difference had the advantage of being an objective, measurement-based indicator.

Is the number of microembolic signals related to neurologic outcome in coronary bypass surgery?

Coronary artery bypass surgery (CABG) without cardiopulmonary bypass (CPB) may potentially reduce the number of microembolic signals (MES) associated with aortic manipulation or generated by the pump circuit, resulting in a better neurologic outcome after surgery. Our aim was to compare the frequency of MES and neurologic complications in CABG with and without CPB. Twenty patients eligible to routine CABG without CPB were randomized to surgery with CPB and without CPB and continuously monitored by transcranial Doppler. Neurologic examination was performed in all patients before and after surgery. The two groups were similar with respect to demographics, risk factors, grade of aortic atheromatous disease and number of grafts. The frequency of MES in the nonCPB group was considerably lower than in CPB patients, however, we did not observe any change in the neurologic examination during the early postoperative period. Neurologic complications after CABG may be related to the size and composition of MES rather than to their absolute numbers. A large prospective multicentric randomized trial may help to elucidate this complex issue