Biomedical subjects

J Rivera

Publications and source records attributed to J Rivera.

292 records · Page 17Linked to original sources

PubMedDate not supplied

A comparative study of two third-generation anti-hepatitis C virus ELISAs.

The sensitivity and specificity of two third-generation screening tests for the detection of antibody to hepatitis C virus (anti-HCV) was evaluated in a side-by-side study (Abbott HCV EIA 3.0/Ortho HCV ELISA 3.0). Specimens that were reactive in either ELISA were then retested by the other ELISA, and confirmed by RIBA-3. The screening of 15,540 serum samples from healthy blood donors showed a significantly lower number of reactive cases tested by Ortho (21 out of 8,805, 0.24%), than tested by Abbott (35 out of 6,735, 0.52%). In the side-by-side comparison, we found that significantly (p = 0.005) more Ortho-positive samples were also reactive in Abbott (14/21, 66.6%), than in Abbott followed by Ortho (7/35, 20%). Moreover, the RIBA analysis revealed a significantly (p = 0.014) higher number of RIBA-positive specimens among those reactive in Ortho 10/21 (47.6%), than among those reactive in Abbott 6/35 (17.2%), thus the former provides a greater positive predictive value. However, we did not observed differences in the sensitivity between Abbott and Ortho, because all RIBA-positive samples demonstrated reactivity in both ELISAs.

Blood Donors↗

PubMedDate not supplied

[Length and weight at birth: the role of maternal nutrition].

OBJECTIVE: To identify determinants of weight (BW) and length at birth (BL). MATERIAL AND METHODS: We studied 481 mother-newborn pairs in three Mexico City hospitals. Multiple regression models were developed to identify statistically significant predictors of BW and BL with respect to a predetermined biological model. Independent variables included were: maternal anthropometry, age, smoking habits, and civil status, parental education, obstetric history, hypertension, and neonatal characteristics. RESULTS: In the group with calf circumference (CC), height and head circumference below the median BW was 133, 92 and 96 g lower (+/- 35 standard error -SE-, p < 0.01) than the group above the median, adjusting for socioeconomic, obstetric history, and neonatal characteristics (NC). In the group below the median CC or height, BL was 5.8 or 6.2 mm (+/- 1.9 mm SE, p < 0.01) respectively, adjusting for obstetric history and NC. CONCLUSIONS: Results suggest that maternal anthropometry is the most important predictor of birth size and that predictors for BW and BL differ.

Adult↗

PubMedDate not supplied

[Capacity of weight-for-age and length-for-age to predict stunting at 3 years of age].

OBJECTIVE: To compare the capacity of two cut-off points of weight-for-age and length-for-age (-1 and -2 standard deviations) at different ages in the interval between birth and 30 months to predict stunting in three year old children. MATERIAL AND METHODS: Data from a longitudinal study in Guatemala were used to evaluate the hypothesis that the capacity of cut-off values of weight-for-age and length-for-age to predict stunting at three years of age varies according to age. RESULTS: Length-for-age at -1 standard deviation (SD) of the WHO/NCHS mean reference values is a satisfactory prognostic indicator of stunting at three years of age during the first semester of life, while the same index at -2 SD is adequate after 9 months of age. Weight-for-age at -1 SD is a suitable indicator only at 9 months and at -2 SD the indicator is satisfactory between 15 and 24 months of age. CONCLUSION: The capacity to predict stunting at three years of age, for weight-for-age and length-for-age cut-off values varies according to age.

Age Factors↗

PubMedDate not supplied

[Energy and nutrient consumption in Mexican women in reproductive age].

OBJECTIVE: To analyze energy and nutrient consumption in Mexican women from 12 to 49 years of age. MATERIAL AND METHODS: Dietetic information was gathered by a 24 h recall from 9,101 women who participated in the National Nutrition Survey conducted in 1988. These data were compared with sociodemographic and physiologic characteristics. Nutrient consumption was compared with the Recommended Daily Allowances (RDA). Variance analysis and t-test were used to evaluate group differences. RESULTS: Mean energy consumption was 1,721 kcal per day. The diet consisted of 15% protein, 60% carbohydrates and 25% fat. The proportion of women with dietary intakes lower than 50% of the RDA was 70% for vitamin A, 75% for vitamin B6, 56% for vitamin C, 33% for vitamin B12, 69% for folate, 33% for calcium and 22% for iron. CONCLUSION: Results show important deficiencies in the diet, predominantly in pregnant and lactating women, in women from low socioeconomic levels and in rural and indigenous women of south of the Mexican republic.

Adolescent↗