Total parenteral nutrition in the newborn: amino acids-energy interrelationships

As part of an ongoing study on the influence of intravenous glucose and fat on nitrogen metabolism we evaluated the relationship between the source of infused energy and plasma amino acid levels. Thirty-two studies were performed in 16 appropriate-for-gestational-age newborn infants (birth weight, 2150 +/- 115 g; means +/- SEM). In a crossover design each patient received two 6-d periods of isocaloric and isonitrogenous infusions, differing only by the source of calories (high or low fat intakes). For an energy intake of 80 kcal.kg-1.d-1 (335 kJ.kg-1.d-1) there was a significant hypoaminoacidemia (2338 +/- 185 vs 2937 +/- 196 mumol/L, high fat vs low fat) under the high-glucose intake. These data suggest that above an energy intake of 60 kcal.kg-1.d-1 (251 kJ.kg-1.d-1) there is a threshold at which changes in plasma amino acid levels are triggered by variations in the source of infused energy. Careful examination of all variables, including energy sources, is essential when aminograms are compared.     

Age-related changes in oxidative capacity differ between locomotory muscles and are associated with physical activity behavior

There is discrepancy in the literature regarding the degree to which old age affects muscle bioenergetics. These discrepancies are likely influenced by several factors, including variations in physical activity (PA) and differences in the muscle group investigated. To test the hypothesis that age may affect muscles differently, we quantified oxidative capacity of tibialis anterior (TA) and vastus lateralis (VL) muscles in healthy, relatively sedentary younger (8 YW, 8 YM; 21-35 years) and older (8 OW, 8 OM; 65-80 years) adults. To investigate the effect of physical activity on muscle oxidative capacity in older adults, we compared older sedentary women to older women with mild-to-moderate mobility impairment and lower physical activity (OIW, n = 7), and older sedentary men with older active male runners (OAM, n = 6). Oxidative capacity was measured in vivo as the rate constant, k(PCr), of postcontraction phosphocreatine recovery, obtained by (31)P magnetic resonance spectroscopy following maximal isometric contractions. While k(PCr) was higher in TA of older than activity-matched younger adults (28%; p = 0.03), older adults had lower k(PCr) in VL (23%; p = 0.04). In OIW compared with OW, k(PCr) was lower in VL (～45%; p = 0.01), but not different in TA. In contrast, OAM had higher k(PCr) than OM (p = 0.03) in both TA (41%) and VL (54%). In older adults, moderate-to-vigorous PA was positively associated with k(PCr) in VL (r = 0.65, p < 0.001) and TA (r = 0.41, p = 0.03). Collectively, these results indicate that age-related changes in oxidative capacity vary markedly between locomotory muscles, and that altered PA behavior may play a role in these changes.     

Diet, smoking and exercise: interrelationships between adolescent health behaviours

A questionnaire measuring smoking status, exercise and dietary behaviour was administered to 932 high school pupils during regular classroom periods. Pupils were taken from three year groups which included 327 year 8 (12–13 years), 313 year 9 (13–14 years) and 292 year 10 (14–15 years). Pupils also indicated whether they could recall classroom teaching on 15 food- and health-related issues. Scores were derived representing self-reported frequency of eating foods that were high in fat, and fresh fruits and vegetables. Smoking was found to be associated with lower levels of exercise, consumption of less fresh foods and greater consumption of fatty foods. In addition, consumption of fresh foods was found to be positively correlated with exercise. These findings have implications for the organization of school-based health education efforts and suggest that health education programmes need to adopt an integrated approach rather than treat health behaviours in isolation from each other.     

Acculturation and interrelationships between problem and health-promoting behaviors among Latino adolescents.

PURPOSE: To examine: (a) the effects of acculturation on a healthy lifestyle including problem behaviors (substance use and sex acts) and health-promoting behaviors (e.g., seat belt use, vitamin intake, hours of sleep per night) and (b) the interrelationships among problem and health-promoting behaviors among Latino adolescents. METHODS: Face-to-face interviews were conducted with Latino adolescents (n = 609) with questions covering the following areas: acculturation, sociodemographics, problem behaviors, and health-promoting behaviors. The participants ranged in age from 11 to 19 (mean = 15) years. Bivariate correlations and factor analyses were used to examine the relationship between problem and health-promoting behaviors. A combination of one-way analyses of variance (ANOVAs), Chi-square tests, and Student's t-tests were used to analyze the effects of acculturation on problem and health-promoting behaviors. RESULTS: Higher levels of acculturation were associated with an increased likelihood of exhibiting problem behaviors and a decreased likelihood of exhibiting certain health-promoting behaviors. Foreign-born Latinos were significantly less likely to engage in problem behaviors. Problem behaviors were likely to co-occur; however, the co-occurrence of health-promoting behaviors was not evident. The results also revealed the co-occurrence of problem behaviors with selected health-promoting behaviors. CONCLUSIONS: Among Latino adolescents, there seems to be evidence that problem behaviors and certain health-promoting behaviors do co-occur. To the extent that "healthy lifestyles" are conceptualized as the presence of health-promoting behaviors and the absence of problem behaviors, less acculturated Latino adolescents seem to fare better than those that are more acculturated. Interventions to promote "healthy lifestyles" among Latino adolescents should be tailored to take into consideration the effect of acculturation.     

Relationship between taste thresholds and hunger under debate

We determined taste recognition thresholds for six compounds (sucrose, fructose, sodium chloride, quinine sulphate, PROP and liquorice) in fasting students and, in the same subjects, after a meal. The testing procedure was the staircase-method in blind conditions. Although taste sensitivity may vary with hormonal status, our results did not show any significant difference in taste recognition thresholds between hunger and satiety. Our Bayesian analysis did not corroborate the hypothesis of increased sensitivity to nutrition-related tastants in the fasting state that was recently supported by data obtained with the two-alternative forced-choice method.     

Age-related changes in lungs' vital capacity in Ryazan schoolchildren

The vital capacity in the 11- and 14-year old boys and 11- and 13-year old girls examined in 1996 to 1999 significantly reduced as compared in the children of the same age. The significant increase in the vital capacity in 15-16-old girls examined in 1996-1999 is due to that in their height, as compared with these indices in those examined in 1976 (by 4.64 and 4.87, respectively).     

Age-related changes in the psychophysiological parameters in male teenagers

The time course of changes in the time of a simple visuaI motor reaction, force and lability of the nervous system, stability of attention and memory was studied in 2104 urban and rural males aged 18-27 years to develop standard phychophysiological status rating tables. It was shown that the score of the central nervous system should be used to detect some functional impairments of the central nervous system. Positive changes in higher nervous performance were noted, which were more pronounced in young rural males. Rating scales were developed to diagnose the individual characteristics of the central nervous system in young men of call-up age.     

A taste of nutrition--a nutrition resource for leaders working with mentally handicapped adults

The trend towards deinstitutionalization for mentally handicapped adults has precipitated a need to provide these individuals with nutrition education and food preparation skills. Food, nutrition, and eating are important components of training programs for life skills, which lead to greater independence for the mentally handicapped. The types of nutrition information and learning activities needed for the mentally handicapped were determined through a literature review and a series of interviews with those working with this target group. The nutritional concerns of mentally handicapped adults include food selection to meet their nutritional needs, menu planning, food preparation, weight control, and nutrient-drug interactions. A Nutrition Resource Kit for Leaders Working with Mentally Handicapped Adults has been developed in The Regional Municipality of York in response to local demand for nutrition education programs and resources for mentally handicapped adults. The kit provides those working with mentally handicapped adults with background nutrition information, learning activities, resource materials, and references to additional resources. The topic areas covered include basic nutrition, nutritional concerns of mentally handicapped adults, nutrient-drug interactions, menu planning, shopping strategies, and food preparation. Dietitian-nutritionists can assist leaders who work with mentally handicapped adults by providing them with up-to-date nutrition information and motivating the to use available nutrition education resources.     

Age-related changes in total and high-density-lipoprotein cholesterol in elderly Dutch men.

OBJECTIVES: This study investigated changes in total and high-density-lipoprotein cholesterol (HDL) concentrations with age and time in elderly men. METHODS: A cohort of men born between 1900 and 1920 from the Dutch town of Zutphen was examined in 1977 and 1978 (n = 571), 1985 (n = 885), 1990 (n = 555), and 1993 (n = 345). Linear regression analysis and random-effects models were used to assess cross-sectional and longitudinal age- and time-related changes in cholesterol concentrations. RESULTS: In both cross-sectional and longitudinal analyses, total cholesterol decreased by 0.04 mmol/L a year with age. The longitudinal change was observed in the entire population as well as in men who participated in all four examinations (n = 135) and in a subgroup of men who were free of common chronic diseases, were not on cholesterol-lowering medication or a prescribed diet, and rated themselves as being "healthy" (n = 64). HDL cholesterol did not change significantly with age neither on a cross-sectional nor on a longitudinal basis. CONCLUSIONS: Among elderly men, total cholesterol diminishes with age both on a cross-sectional and on a longitudinal basis; HDL cholesterol does not vary with age in any way.     

Age-related changes in social and psychological models predicting dental care in children

Social and psychological factors associated with dental care were examined in two groups of children ages 6-8 and 9-11 years. Level of surface plaque, measures of dental health status (that is, total number of primary teeth decayed, missing, and filled [dmft] and total number of permanent teeth decayed, missing, and filled [DMFT] ), and frequency of dental visits were used as indicators of preventive behavior. The importance of social and psychological factors associated with these indicators was shown to vary with age group and with the specific preventive behavior indicator. Perceived level of dental anxiety and dental vulnerability were significantly associated with dental care, with dental anxiety being an important factor only in the lower group. Accessibility to a free school dental service was an important predictor of dental health status (DMFT) in the older age group, however, the data indicate that only when this service was offered within an organized structure of referral and transport was there an optimal effect on subsequent dental health.     

Age-related changes of the somatosensory evoked potentials in healthy children

AIM: The aim of the study was to investigate the configuration and latency of the somatosensory evoked potentials (SEPs) in healthy children for the time from the neonatal period to adolescence. MATERIAL AND METHODS: SEPs were recorded in 67 healthy children--37 boys and 30 girls from 0 to 16 years of age by means of median nerve stimulation. The active electrode was placed above the contralateral parietal cortex on places C3' and C4' and the reference electrode--on Fpz. The filters were 10-1000 Hz and the frequency of the electric stimulus--3 Hz. RESULTS: The depression of the potential in the neonatal period is accounted for by the wide base and low amplitude of SEPs. The configuration of SEPs is identical with that of adult individuals after 3 years of age. The latencies of the waves P15, N20 and P25 decrease progressively with age and lengthen in the period from 9 to 16 years of age, with the increase of height. The interpeak latencies P15 - N20, N20 - P25 and P15 - P25 decrease with age, while the amplitude N20/P25 increase with age. We found significant variability in the amplitude of the potential, most pronounced in the neonatal period. It gradually decreases by 10-14 months of age and after that remains unchanged. We did not find any differences at stimulation between the left and the right hand. CONCLUSION: The age-related changes in SEPs reflect the trends of the development and the maturation of the neural pathways and their better myelinization.