Search PubMed⌕ Search

Biomedical subjects

M E Valencia

Publications and source records attributed to M E Valencia.

80 records · Page 5Linked to original sources
PubMed1984

[Elaboration, by linear programming, of new products from cereals and legumes].

The differing contents of essential amino acids in cereals and legumes bring about an overall increase in protein quality when these foods are consumed together. This study describes a least cost formulation method for preparing products based on cereals and legumes using linear programming. The mixture was formulated under different constraints; from a nutritional standpoint, a given amino acid pattern, and another one on a technological feasibility constraint, which depends on the type of product to be elaborated. From the formulation based on wheat, chick-pea, sorghum, and soybean flours, three products were developed: bread, tortillas and cookies; from these, bread was selected for further evaluation. The product was chemically evaluated by proximate analysis composition, and amino acids were determined by HPLC. Biological evaluation was performed by the PER and RPV methods, obtaining a PER of 1.69 for the developed bread product, and of 0.68 for the control bread. The RPV for the developed product was 64.31% of lactoalbumin and 23% for the control bread, which represents an increase of 41%. The sensory evaluation results did not indicate significant differences in taste, texture, color or overall acceptability of the developed bread product as compared to the control.

Amino Acids, Essential↗
PubMed1984

[Relation between familial income, expenditure and food consumption in marginal urban zones of Sonora, Mexico].

This research project in urban marginal areas of the City of Hermosillo in Sonora, Mexico, analyzes certain socioeconomic factors taking into consideration the relationship between household income, expense and consumption of food. The study is based on information collected in a 24-hour recall survey carried out for all members of the family, frequency of consumption of foods, and a socioeconomic questionnaire. Expense and consumption of foods was divided into five different income groups and into three classes of foods: basic foods, fresh meat and high-protein foods. The results of the research study show a direct relationship between household income level and expense and consumption of the foods. The income-elasticity of the demand of basic foods was lower than that estimated for high-protein foods, and there was a marked tendency to increase consumption of high-protein foods as family income increased. More than 50% of the calories and proteins were obtained from the basic foods group, even though a large percentage of family food expense was destined for high-protein foods. The study concludes that more research is needed at a macroeconomic level to understand the basic underlying causes of the nutritional problems.

Costs and Cost Analysis↗
PubMed1980

Energy utilization in laying hens. III. Effect of dietary protein level at 21 and 32 C.

White Leghorn pullets housed at either 21 or 32 C were used to investigate the effects of dietary protein level on energy utilization. Protein levels of 12, 14, 16, 18, and 20% were employed in this study with three feeding levels of each (two restricted levels and ad lib.). All diets were isocaloric, and the duration of the study was 21 days. Maintenance metabolizable energy (ME) was estimated as 134 and 121 kcal/kg physiological body weight (BW.75) at 21 and 32 C, respectively. Fasting heat production/BW.75 was 21% higher at the lower temperature (89 vs. 70 kcal). Estimates of energetic efficiencies at 21 C varied from 60.9% for the 12% protein diet to 72.4% for the 18% protein diets. At 32 C, similar diets showed lower energetic efficiencies for ME conversion to net energy (50.6% for the 12% protein diet and 70.6% at 20% protein) due to lower feed intakes. Egg weights were significantly higher at the lower environmental temperature, and at each temperature they were increased with the feeding of the higher protein diets. The average feed efficiency (g egg/g feed) was significantly better at the higher environmental temperature (.46 vs. .53). Calculations of heat increment (HI) plus activity from a parabolic regression developed in relation to protein intakes showed higher (HI plus activity) values with either low or high protein intakes. Thus, the feeding of dietary protein levels which result in intakes commensurate with needs should result in maximum energetic efficiencies and dietary net energy.

Animals↗
PubMed1978

Energy utilization by laying hens. I. Energetic efficiencies of maintenance and production.

The energetic efficiency of metabolizable energy conversion to net energy for maintenance and/or production was determined in laying hens. The techniques employed indicated that maintenance and production had essentially the same efficiencies (.619 and .628, respectively). Fasting heat production was 69.28 kcal/Wkg75 (physiological body weight) and the maintenance requirement was 111.1 kcal/Wkg75. Limiting metabolizable energy intake in laying hens reduced both egg weight and hen-day production. Regression equations predicted a reduction of 1.53 g in egg weight and a reduction of 2.5% in egg production for each 10 kcal metabolizable energy reduction in intake. This paper reports techniques which may be employed for energetic efficiency evaluations of feedstuffs, mixed diets, and energy utilization by laying hens in short term studies.

Animal Feed↗
PubMedDate not supplied

Response to liposomal doxorubicin and clinical outcome of HIV-1-infected patients with Kaposi's sarcoma receiving highly active antiretroviral therapy.

PURPOSE: HIV-associated Kaposi's sarcoma (KS) may not resolve despite highly active antiretroviral therapy (HAART). Moreover, the therapeutic goal has shifted from palliative care to long-term durable complete remission. The objective of the study was to assess the impact of liposomal doxorubicin in the treatment of HIV-associated KS in the HAART era. METHOD: In this prospective, noncomparative, multicenter study, patients with more than 10 cutaneous lesions or visceral disease were treated with 20 mg/m(2) of liposomal doxorubicin (Caelyx) every 3 weeks in addition to their antiretroviral therapy. In addition to tumor measurements and laboratory tests, human herpes virus 8 (HHV-8) polymerase chain reaction (PCR) in peripheral blood mononuclear cells (PBMC) was performed. RESULTS: Out of 79 participants enrolled in the study, 47 (59%) had stage T(1), 41 (52%) I(1), and 32 (40%) S(1). Nine individuals were not evaluable for response, 32 (40%) had complete response, 30 (38%) partial response, 5 (6%) stable disease, and 3 (4%) progression. Regression analysis did not find any statistically significant factor predicting response. HHV-8 PCR was positive in 37/53 (70%) patients with available PBMC samples, and HHV-8 viremia cleared in 14/27 (52%) without correlation with clinical response. Eleven (14%) participants experienced a relapse of KS, while at the last update of data, 49 (62%) remained stable. The only risk factor for recurrence identified was the follow-up time (odds ratio [OR] 1.21, 95% CI 1.07-1.36; p =.002). CONCLUSION: The response rate of AIDS-associated KS to liposomal doxorubicin administered with HAART was high, and most often the response was durable. HHV-8 viremia did not correlate well with clinical outcome.

AIDS-Related Opportunistic Infections↗
PubMedDate not supplied

[Anthropometry and body composition in persons over 60. The importance of physical activity].

OBJECTIVE: To measure anthropometric indicators of body composition by electric bioimpedence, as well as physical activity, blood glucose and arterial pressure in rural people over 60 years of age. MATERIAL AND METHODS: A total of 54 subjects over 60 years old were selected by intentional non-probabilistic sampling. They were subjected to a standardized protocol to measure anthropometric indicators, body composition by electric bioimpedance (EBI), and physical activity was determined by an activity questionnaire. Arterial pressure and glucose tolerance levels were also measured. Analysis included Student's t test to detect differences by sex and the association of physical activity, body composition and other variables by simple linear regression and Pearson's correlation coefficient. RESULTS: Physical activity correlated negatively with percent fat (r = -0.36; p = 0.007) and diastolic (r = -0.36; p = 0.006) and systolic blood pressure (r = -0.32; p = 0.018), and body mass index with post dose glucose (r = 0.31; p = 0.024). CONCLUSIONS: Physical activity in this age group may have a favorable impact with respect to the mentioned health indicators.

Aged↗
PubMedDate not supplied

[Effect of supplementation with a massive dose of vitamin A in children 6 to 36 months of age].

OBJECTIVE: To evaluate the impact of a single massive dose of vitamin A on the vitamin and iron status in children of margined urban areas in Hermosillo, Sonora, Mexico. MATERIAL AND METHODS: A total of 60 children received one dose of 100,000 IU (children from 6 to 12 months) and of 200,000 IU (children from 12 to 36 months) of retinol palmitate distributed by the Health Ministry in June, 1994. Serum levels of retinol, carotenoids, iron, transferrin and ferritin were measured at three periods: basal, after two weeks and after three months. RESULTS: The mean for retinol basal values was 0.7 mumol/l, after two weeks it was 0.97 mumol/l (p < 0.001) and after three months it was 0.83 mumol/l (p > 0.05). When basal values were measured, 6.3% of the children showed severe vitamin A deficiency, which disappeared in the periods following the supplement; additionally, 42% showed moderate deficiency which had decreased to less than 7% after three months. No differences were found for serum iron and transferrin levels (p > 0.05), however, ferritin levels increased (p < 0.001) after three months indicating an improvement in iron reserves. CONCLUSIONS: Massive dose distribution may have an important impact on vitamin A and iron status in children.

Biomarkers↗