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M Ruz

Publications and source records attributed to M Ruz.

29 records · Page 2Linked to original sources
PubMed1989

[Index of nutritional quality per volume: a new indicator to evaluate the nutritional quality of food preparations and diets].

The purpose of this study was to propose a new dietary index to evaluate the nutritional quality of common dishes and diets: the index of nutritional quality per volume (INQV). In its expression, this index takes into account the nutrient density (amount of nutrient/1,000 g of diet) and the nutrient density per reference volume. The last one is the ratio between the recommended allowances of the nutrient and the volume that it is possible to consume during the day, when the diet is offered freely. Zinc was used as example in the analysis. A total of 14 dishes of habitual consumption in Chile were studied in relation to its consumption by 30 preschool children. The volume that children were able to consume was determined by differential weighing between the amount offered and the amount left on the dish, during a period of 180 days. The percentage of water and energy value were established by means of chemical analysis performed according to the AOAC, and the zinc concentration by atomic absorption spectrophotometry. The results of the INQV were then compared with those of the index of nutritional quality (INQ), which considers zinc density/1,000 kcal, and zinc and energy requirements. This comparison demonstrated that the INQV values were lower than those of the INQ in dishes with energy densities lower than 1.0 kcal/g. The opposite tendency was observed in the case of those dishes with energy densities higher than 1.0 kcal/g. The analysis herein presented demonstrates the usefulness of the INQV in diets which are voluminous and with low energy densities, commonly consumed by the low socioeconomic strata of developing countries.

Child, Preschool↗
PubMed1986

[Energy metabolism during placental development in rats--effect of chronic maternal malnutrition].

The effect of maternal malnutrition on the energy metabolism of the developing rat placenta, related to fetal growth, was studied. Female virgin rats of the Wistar strain were fed restricted amounts of 25% casein diet, from puberty and throughout pregnancy. According to results, a significant decrease occurred in the activity of adenylate kinase, as well as a significant increase in the energy charge of the adenylate system (ATP, ADP), per gram of DNA of placental tissue near term, in the malnourished group. The data suggest that the significant increase of energy charge (ATP + 1/2 ADP:/ATP + ADP + AMP) of the placenta in the malnourished group, is the consequence of an inhibition of the reactions controlling ATP-consuming process, such as macromolecular synthesis pathways and active transport of substrates near term. This coincides with the simultaneous and significant decrease in fetal growth in this group.

Adenylate Kinase↗
PubMed1983

[Cellular growth of uterus, placenta and fetus during chronic maternal caloric restriction in rats].

Wistar strain female rats were maintained with restricted amounts of 25% casein diet before and during pregnancy. Uteri, placentas and fetuses were removed from the rats beginning the 14th day of conception and continuing it up to the 20th day. Tissues were analyzed in regard to weight, nucleic acids and protein content. A 25% food restriction decreased dramatically the uterine, placental and fetal size as well as DNA content. RNA and protein content were also found diminished, but it must be emphasized that these findings were less important than the DNA content reduction observed. This is the reason why RNA/DNA and protein/DNA ratios were markedly elevated in regard to control values. Cellular changes observed in the reproductive organs and their relationships with fetal growth failure, induced by maternal dietary modification, are discussed.

Animals↗
PubMed1982

[Chemical composition of human milk. Influence of the nutritional status of the nursing mother].

The chemical composition of human milk obtained from 16 underweight women and 25 controls collected at four, eight and 12 weeks of lactation, was determined in order to assess the effect of maternal nutrition upon milk quality. No meaningful differences were observed for protein, lactose, energy, calcium, iron and copper contents. The values obtained are comparable to those reported in the literature from developed countries. As to Zn content, both groups exhibited decreased values with time, with significant higher values for the controls at the 12th week of observation. Magnesium showed exactly the opposite behavior. On the basis of the present study, it is concluded that maternal nutrition does not condition important changes in the chemical composition of human milk. The authors propose the application of comparable methodologic and analytical criteria, in order to achieve a more complete understanding of the relationships between maternal nutrition and lactation.

Calcium↗
PubMed1981

[Influence of the preconception maternal nutritional status on fetal growth and development in rats].

A study was carried out in Wistar female rats to determine the influence of maternal preconceptional undernutrition on fetal growth and maternal-fetal exchange of energy and nitrogen retained by pregnant rats, with and without supplementary feeding, in comparison to a control group. Experimental malnourished female rats and controls of similar weight, were mated for a single period of 24 hours. From the first day of gestation one group of malnourished and one group of the control rats were fed for 20 days a casein diet with NDpCal% 12, and the other group of malnourished and control pregnant rats were fed NDpCal% 4 during 20 days. At the end of the trials rats were sacrificed: nitrogen, fat and energy values of samples of extracted fat and portions of dried fat-free in the maternal carcass and uterine contents were determined. Both malnourished groups fed during pregnancy with NDpCal% 12 or 4, utilized nitrogen and energy more efficiently, but failed to reach the body weight of the pregnant control rats fed with NDpCAl% 12 or 4, respectively. Food supplementation of the malnourished group during gestation allowed the maternal carcass to catch up growth. The litter size, however, remained diminished, fetal growth improved poorly and the uterine content weight attained only 45% of the maximum of the controls fed on NDpCal% 12. These results showed that when supplementation was imposed only during pregnancy, the recovery of maternal tissue was prioritary, while nutrition of the fetus was secondary.

Animals↗
PubMed1979

[Activity of delta-aminolevulinic synthetase, cytochrome oxidase and levels of the mixed function oxidase system during experimental protein malnutrition. Response to re-alimentation].

Activities of delta amino levulinic synthetase (DALS), cytochrome oxidase (E. C. 1.9.3.1.), NADH cytochrome b5 reductase (NADH red.), NADPH cytochrome P450 reductase (NADPH red.), contents of cytochrome P450 (cyt. P450) and cytochrome b5 (cyt. b5), and levels of hemoglobin and hematocrit were studied in three groups of rats: a) malnourished, b) during recovery from malnutrition, and c) controls. During severe protein malnutrition blood levels of hemoglobin and hematocrit were found to be decreased as well as DALS's activity in homogenized bone marrow and liver. The activity of NADH red, and contents of cyt. P.450 and cyt. b5 in hepatic microsomes were also found significantly depressed. The microsomal activity of NADPH red. as well as mitochondrial cytochrome oxidase did not present significant changes, since values obtained in malnourished rats were similar to those found for the control group. While recovering from malnutrition, when rats were fed a casein based diet (10 NDpCalo/o) supplemented with Fe and Cu, the hepatic enzymatic activities, the cytochrome contents of P450 and b5, and hematocrit experienced a spectacular increase, reaching towards the end of the refeeding period values which could be compared to those found in the control group. Nevertheless, DALS' activity in homogenized bone marrow and hemoglobin levels remained low. Results are discussed in relation to depressed activities and contents of enzymes, coenzymes, metabolites and subtrates involved in the hemoglobin synthesis in the rat bone marrow, during recovery from malnutrition.

5-Aminolevulinate Synthetase↗