Human nutrition. Clinical nutrition最新文献

To study the interaction between diarrhoea and malnutrition, an average of 300 children aged 5-24 months were followed from January 1981 to January 1983 in Teknaf, Bangladesh. Diarrhoea episodes, differentiated according to stool appearance, were recorded weekly while weight and height measurements were taken every 6 months. Results showed no relationship between the nutritional indicators and diarrhoea incidence recorded within 60 d after anthropometric assessment. However, the duration of dysentery was significantly longer in the severely malnourished children who were stunted but not for those wasted. Although many children with watery diarrhoea had episodes of long duration, these were not associated with any nutritional indicator. We conclude that the key factors in this interaction are the invasive type of pathogen and chronic malnutrition.

The resting metabolic rates (RMRs) of 10 adult males of body mass index around 19 were estimated between 6-36 (mean 18.2 +/- 2.3) months of an earlier recording. There were no significant differences in the body weights, RMRs and respiratory quotients (RQ). The coefficients of variation (CV) of intra-individual differences in body weight and RMR were both 2.5 per cent. In those subjects who showed a change in body weight ie, greater than +/- 1 kg over a period of 22.0 +/- 3.0 months, the CV (4.3 per cent) of weight change was greater than the CV (1.9 per cent) of intra-individual differences in RMR.

Twenty-two children with Down syndrome (DS), 8 boys and 14 girls, in the age range 5 to 15 years were investigated and compared with a control group of 22 healthy children, 9 boys and 13 girls of the same age group, 9 of them being siblings of patients with DS. Concentrations of iron, copper and zinc in serum were determined by atomic absorption spectrophotometry and serum proteins were quantitated by the radial immunodiffusion technique. The subjects with DS had significantly lower mean serum iron (P less than 0.01) and zinc (P less than 0.001) than the healthy controls. Four DS children had serum iron values that fell below the normal range. In more than 60 per cent of the DS patients the zinc concentration fell below the normal range. The children with DS had significantly higher mean serum copper (P less than 0.05) but lower serum iron (P less than 0.05) and zinc (P less than 0.05) levels than their healthy siblings living in the same family at the time of examination. The DS patients as a group had higher levels of caeruloplasmin (P less than 0.01), haptoglobin (P less than 0.001), orosomucoid (P less than 0.001) and alpha 2-macroglobulin (P less than 0.001) than the healthy controls and compared with their siblings. Except for prealbumin and retinol-binding protein (RBP), no age-related variation in the serum concentrations of the studied proteins was found in the DS patients. Albumin, prealbumin, RBP and transferrin levels were similar in the two study groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Forty-three apparently healthy young adult male volunteers underwent an evaluation of their nutritional status, blood chemistry and faecal excretion of enteropathogens, which did not reveal current malnutrition or illnesses. Ten of them were further studied for small intestinal histology, culture of aerobic and anaerobic bacteria in the duodenal juice, disaccharidase activities, glucose absorption and faecal excretion of fat and nitrogen. The study revealed mild morphological changes associated with the appearance of anaerobic bacteria in the upper intestine, decreased glucose transport and increased faecal losses of nitrogen. Although all these changes were rather mild, they may be significant for people whose diet is of borderline nutritional quality.

Studies were carried out in eight normal adults to simplify the continuous infusion-end product method for measuring whole-body protein turnover using 15N-glycine. When a priming dose of label suitable for the urea pool was followed by intermittent oral doses of label, plateau enrichment was maintained in urinary urea and ammonia from 9 to 18 h, giving values for nitrogen flux (18 h) of 0.69 +/- 0.05 g N/kg/d with urea and 0.46 +/- 0.01 g N/kg/d with ammonia. With a priming dose appropriate for the ammonia pool, plateau was reached in urinary ammonia in less than 120 min and maintained for up to 6 h. Nitrogen flux (3 h) with oral 15N-glycine was 0.96 +/- 0.12 g N/kg/d, and with intravenous label was 0.61 +/- 0.13 g N/kg/d. There was a significant linear relationship between flux measured with oral and intravenous isotope. It is suggested that different components of protein turnover are measured with the different approaches, and that the short method in particular measures rapidly turning over proteins associated with the gastrointestinal tract.

Anthropometric parameters (height and weight) were used to assess the nutritional status of 1407 black children in a Soweto lower primary school. Cross-sectional profiles were obtained in 1981 and 1983 as well as a longitudinal study of 362 pre-adolescent children who remained in the school over the 2-year period. The major proportion of the distribution of percentage weight-for-age and percentage height-for-age was less than 100 per cent of NCHS reference median. There was a small but significant increase in mean percentage weight-for-height between 1981 and 1983. Children who were stunted and those whose growth rate over a 2-year period was known to be reduced failed more frequently. Apart from these the general range of anthropometric findings did not clearly correlate with classroom achievement as assessed by end-of-year marks. The age ranges of children in the different grades exceeded 5 years. The highest failure rate occurred in the school entry grade (Substandard A). Only in this grade were the older boys found to be less adequately nourished than their age peers in higher standards. Untested adverse social, family and environmental effects may mask the real consequences of suboptimal growth. Without anthropometry the latter would frequently not be apparent because of the generally proportional reductions in weight and height for age.

The intrasubject precision of the doubly labelled water method was investigated as a function of increasing length of the metabolic period and decreasing initial isotope enrichment. This analysis was performed in seven subjects following a single dose of isotope and three subjects who received multiple doses of isotope. The intrasubject precision was 5-6 per cent for periods of up to 14 d. This is only slightly larger than that predicted from our previously published model in which we assumed that analytical error was limiting precision. Intrasubject precision worsened with increasing length of the metabolic period and with decreasing initial isotope enrichment, but the loss of precision was two to ten times greater than that predicted by the model. The use of the intercept method to determine the isotope dilution spaces did not improve precision. We speculate that one cause of the failure of the model is that it does not consider unmeasured changes in natural isotopic abundances associated with dietary intake. Results demonstrate the importance of choosing a dose that provides an initial isotope enrichment that is 500-600 times the analytical error, and a metabolic period that is between one and three biological half-lives of the isotopic tracers.

Evaporative and sensible heat losses were measured during sleep in 38 male and 21 female subjects in a direct whole-body calorimeter (24 m3). The subjects were all apparently healthy, had a mean body weight of 66 kg and had spent the preceding day in the calorimeter performing different fixed physical activity programmes. Heat losses were measured continuously between 11.30 p.m. and 6.30 a.m. The average (+/- s.e.m.) rate of total heat loss during the 7h of sleep was 90.6 +/- 1.21 and 74.4 +/- 1.22 watts for men and women respectively. The total heat loss during basal resting conditions immediately following sleep was 83.8 +/- 1.5 and 69.2 +/- 1.6 watts, respectively. Heat production during basal resting conditions, as measured by indirect calorimetry about 1 h after awakening on the morning of the preceding day, was found to be 85.6 +/- 1.3 and 71.2 +/- 1.1 watts, respectively. The increase in heat loss during sleep above that of basal resting conditions could largely be attributed to an increase in the evaporative heat loss. The heat loss fell during the night by about 14 per cent in women and about 30 per cent in men, approaching basal resting values in the last hour of sleep. Heat production during sleep was calculated for the male subjects by correcting the heat loss data for the published decreases in rectal temperature during the night and was found to be on average 9 per cent lower than the heat loss. The present data, as well as previously reported data, suggest that the energy expenditure of sleep is 0.95 X BMR rather than 1.0 X BMR as reported in the recent FAO/WHO/UNU Expert consultation (1985).