M. Guillermo Herrera

Decreased Weight Gain and Food Intake in Vagotomized Rats

Summary Subdiaphragmatic truncal va-gotomy, alone and with pyloroplasty, was performed in intact rats. In all instances, vagotomized animals ate less and gained less weight than controls during a prolonged period of postoperative observaton. We acknowledge the invaluable assistance of Ms. Lidija Trencis-Buck in performing surgery, Dr. Mo-hamed el Lozy in computation and analysis, and L. La Brecque and T. Poindexter in caring for the animals.

An Electron Microscopic Study of Lipoprotein Production and Release by the Isolated Perfused Rat Liver.

Summary Dense osmiophilic bodies, 300-800 Å in diameter, appear in isolated rat livers perfused with high concentrations of linoleic acid. After 2 minutes of perfusion, these bodies are very numerous in the endoplasmic reticulum and Golgi apparatus. They are first seen in significant numbers in the space of Disse at 5 minutes. Similar granules are present in the final media of livers perfused with fatty acid and the d < 1.006 fraction of human and rat sera. The data suggest that these bodies are very low density lipoprotein and indicate that the isolated perfused liver is an excellent experimental system for morphological study of lipoprotein metabolism.

Stimulation of metabolic activity of adipose tissue from fasted rats by prolonged incubation in vitro: I. requirement for glucose and insulin

Abstract 1. 1. Rat epididymal adipose tissue may be incubated in Eagles tissue-culture medium for periods as long as 36 h without evidence of serious metabolic deterioration. Tissue transfer to new medium was carried out every 4.5 or 6 h. Sterile media were used, although without strictly sterile transfer technique; penicillin and streptomycin were present throughout. 2. 2. Continued viability of the tissue was evidenced by persistent glucose uptake, oxidation of glucose to CO 2 , and fatty acid as well as protein synthesis from glucose, together with intact sensitivity to insulin throughout. However, from 24 h on there was a tendency to increased production of lactate by the tissue, together with a slight decrease in glucose oxidation, suggesting increasing occurrence within the tissue of anaerobic glycolysis. 3. 3. The grossly depressed metabolic activity of adipose tissue obtained from animals fasted 96 h was restored toward normal by preincubation of the tissue for periods ranging from 4.5 to 24 h, provided that the preincubation medium contained glucose and insulin or human serum. Increased lipogenesis, together with increased ability to oxidize glucose to CO 2 and to incorporate glucose carbon into protein, reached a plateau after approx. 9 h of preincubation. 4. 4. Although tissue-culture medium was used in most of these studies, the presence of essential amino acids and co-factors required for tissue cell growth in vitro was not required for the occurrence of the preincubation effect upon lipogenesis and glucose oxidation in adipose tissue. 5. 5. Lipogenesis from pyruvate, and pyruvate oxidation to CO 2 a were not affected by preincubation of epididymal adipose tissue from severely fasted rats. The presence of insulin was without effect upon pyruvate metabolism either before or after pre-incubation with glucose. However, preincubation without glucose in the presence of pyruvate with or without insulin, restored the lipogenetic activity of adipose tissue from glucose in a manner similar to that observed when preincuuation was carried out in the presence of glucose and insulin. 6. 6. Several enzymic activities concerned with glucose and fatty acid synthesis were measured in the homogenate of adipose tissue from severely fasted rats, both immediately after killing the animal and following preincubation with glucose and insulin for 9 h. In no instance was an increase in any of the enzymic activities measured noted; in most instances a very slight decrease, of the order of magnitude of 5%, was seen. 7. 7. The most likely but still hypothetical explanation for the increased lipo-genetic activity of adipose tissue of fasted rats after preincubation is the accumulation (or re-accumulation) within the tissue of metabolic products or metabolites which in themselves stimulate lipogenesis. These metabolites would require the presence of insulin to arise in sufficient quantity from the metabolism of glucose, but would arise from the metabolism of pyruvate in adequate amounts even in the absence of insulin.

Sex related effects of nutritional supplementation during pregnancy on fetal growth.

Nutritional supplementation of low income women during pregnancy increased birth weight significantly only in the male offspring. No differences by sex were apparent in the amount of supplementation, length of gestation or maternal characteristics known to be associated with birth weight. Regression analysis revealed a significant supplementation by sex interaction. The fetal growth curve of the supplemented males was higher and roughly parallel to the curve of females, and showed an effect of supplementation prior to 35 weeks of gestation. These findings and those of other authors support the hypothesis that fetal growth of males towards the end of pregnancy is more rapid and hence more susceptible to adverse environmental influences than that of females. This is reflected in a reduction of the difference in birth weight in favor of males observed in well-nourished populations. It is postulated that male subjects therefore exhibit sensitivity to nutritional supplementation of their mothers during pregnancy.

Reduced visual resolution acuity and cerebral white matter damage in very-low-birthweight infants

Neonatal cerebral white matter echolucencies predict visual resolution acuity deficits in very-low-birthweight (VLBW) infants. We examined maternal sociodemographic, lifestyle, intrapartum, infant birth/perinatal, and ocular motor/refractive characteristics to determine whether they accounted for this association in infants who were tested once between postnatal age 25 and 56 weeks (corrected for gestational age at birth). Cranial ultrasound scans were read by consensus to identify echolucency in a population of VLBW infants with no known ocular abnormalities. Visual resolution acuity was measured with the Acuity Card Procedure (ACP) in 14 infants with echolucency and compared with that of 81 VLBW infants born in the same hospitals with normal ultrasound scans. In time-oriented logistic regression models, echolucency remained a consistent predictor of abnormal visual resolution acuity after adjustment for covariates in three developmental periods (pre-, peri-, and postnatal). Odds ratios ranged from 19.3 (95% confidence interval, 4.5 to 82.2; p=0.001) to 10.4 (95% confidence interval, 1.3 to 81.9; p=0.03). Reduced visual resolution acuity in VLBW infants appears to be due to cerebral white matter damage.

Food supplementation of pregnant women at risk of malnutrition and their newborns' responsiveness to stimulation.

Pregnant women at risk of malnutrition were enrolled in a health care programme in Colombia, South America, and were randomly assigned to a group receiving supplementary food or to a control group at the beginning of the third trimester of pregnancy. There were no differences between the groups in social or nutritional variables.

Growth Data Analysis in FTT Treatment and Research

Assessment of growth status in the FTT child is central to both diagnosis and treatment of this complex syndrome. In clinical practice and in research, growth data analysis are used to assess the impact of organic and nonorganic risk factors and to evaluate the effectiveness of treatment. In the FTT child, growthis the indicator of overall progress. The short and long term effectiveness of medical, nutritional, behavioral, and mental health interventions is measured by the physical growth outcome. Likewise, nutritional rehabilitation contributes to positive psychosocial outcomes, such as improved developmental quotients and enhanced mother-child interactions.

The impact of supplementary feeding and home education on physical growth of disadvantaged children

Abstract Urban Colombia families with malnourished children were randomly assigned to treatment groups receiving either or both of a diet supplement and a home education program. The effectiveness of these interventions, both separately and interactively, in augmenting the physical growth of children during the first 36 months of life was assessed longitudinally. Children receiving the supplement were significantly taller and heavier than nonsupplemented controls after three months. Proportional weight for height over age was similar in all groups, while the supplement ameliorated the trend toward stunting. Home education moderately enhanced the supplementation effect, but alone did not improve growth. It is concluded that stunting without concomitant wasting may result from long-term deficiencies in calorie and protein intake and/or frequent disease episodes. Under such circumstances, measures of wasting (weight for height) would not be sensitive to the impact of long-term programs. Height for age would be a preferable outcome variable.

Similar and opposite effects of dibutyryl cyclic AMP and insulin on glucose metabolism in adipose tissue

Abstract The effects of N6-2′-O-dibutyryl cyclic AMP on glucose metabolism and lipolysis in fragments of rat epididymal adipose tissue were studied. Measurements were made of glucose uptake, conversion of glucose carbon to CO2 and tissue fatty acids and glyceride-glycerol, lactate production, and glycerol release. Low concentrations of dibutyryl cyclic AMP (0.1–0.5 mM) increased all parameters of glucose metabolism and inhibited glycerol release in tissue from both normally fed and fasted rats. Higher concentrations of dibutyryl cyclic AMP (3–5 mM) diminished glucose utilization and greatly accelerated lipolysis. Insulin, 50 μunits/ml, accelerated glucose metabolism in the presence of either low or high concentrations of dibutyryl cyclic AMP though the effect of insulin was greatly reduced by 3 mM dibutyryl cyclic AMP. Tissue exposed to concentrations of dibutyryl cyclic AMP which inhibited glucose metabolism (5 mM), then rinsed and reincubated without dibutyryl cyclic AMP, displayed increased glucose utilization. The results of these experiments emphasize the need for caution in interpretation of the effects of dibutyryl cyclic AMP on adipose tissue metabolism and the need for further research to elucidate the role of cyclic AMP in the regulation of glucose metabolism.

Problems in sibling matching designs: A case report†

A pilot project was carried out in order to study the effects of malnutrition upon cognitive development utilizing a design of sibling matching to control social and health variables. The results of this study showed that matching is only partially effective as a means for controlling non‐nutritional factors. Three major problems impeding further control were encountered: inaccessability of nutritional, social and health history in older siblings; age inhomogeneity within younger and older groups; and differences between experimental and control groups in the relationship of social covariates to the dependent variable. Failing to adequately control non‐nutritional variables would tend to falsely augment the effect of malnutrition upon intellectual functioning.