Biomedical subjects
Publications and source records attributed to D Molnar.
Coarse grained Langevin-type effective field equations may provide some guidance for the analysis of mesoscopic or microscopic molecular systems exhibiting fluctuations, or for systems of hundreds to thousands of atomic or subatomic particles produced in atomic or high-energy nuclear collisions. Suggestions for consistent realization of random fluctuations in discretized fluid dynamics will be presented.
Energy metabolism was measured in children receiving long-term treatment with valproic acid. In 8 of 10 randomly selected subjects, the resting respiratory quotient was higher than in age- and sex-matched control subjects (0.91 +/- 0.01 vs 0.87 +/- 0.01; p < 0.05). A shift was observed in fuel consumption, and a significant reduction was found in the amount of fats oxidized (0.68 +/- 0.23 vs 1.18 +/- 0.18 gm.kg-1.day-1), which was accompanied by increased utilization of carbohydrates (5.31 +/- 0.79 vs 3.81 +/- 0.39 gm.kg-1.day-1) in comparison with the control subjects. The resting total energy expenditure was not affected by the treatment. The children with an altered energy consumption pattern (n = 8) received carnitine supplementation for a month; the respiratory quotient then decreased (0.87 +/- 0.02), the oxidation of fats increased (1.42 +/- 0.25), and the consumption of carbohydrates decreased (3.87 +/- 0.79), but no changes in resting energy expenditure were observed. We conclude that carnitine depletion, a known adverse effect of valproic acid administration, may result in inhibited fatty acid oxidation, leading to a shift of substrates utilized from fats to carbohydrates.
Simple, incentive based behaviour modification, with or without a modest programme of psychotherapy involving outpatient visits every four to six weeks, seems to be associated with a useful cure rate in children with lower bowel function disorders. Appreciable social disadvantage seems to be the most important factor mitigating against a successful outcome, associated with non-compliance with treatment. Failure to respond to treatment was associated with important psychological problems. These were more common in the socially disadvantaged groups. Children from satisfactory social backgrounds who have lower bowl disturbances can be effectively treated by fairly simple programmes. More elaborate and expensive strategies should be reserved for those whose psychosocial circumstances make it possible to predict a less satisfactory outcome.
Anorectal manometry and suction biopsy were carried out on 47 children with constipation or soiling, or both. Patients were divided into two groups. Group 1 (37 patients): functional faecal retention, group 2 (10 patients): functional faecal soiling without retention. Ganglion cells or normal acetylcholinesterase staining, or both, was demonstrated in all cases. Normal inhibition of internal sphincter could be achieved by rectal distension in all except 2 children with severe constipation. Resting sphincteric pressures, pressure responses, and conscious rectal sensitivity thresholds were similar in groups 1 and 2, but were increased compared with controls. In group 1 alone, the critical volume increased parallel with conscious rectal sensitivity threshold. Since the complete relaxation of internal sphincter occurs before conscious rectal sensation arises in children with soiling without retention, this may be an important factor, at least in some of the soilers.
The metabolic and hormonal effect of Escherichia coli endotoxin injected intraperitoneally was studied in fed and starved rabbits aged 6-9 days. Fed rabbits responded to endotoxin with fever, starved animals became hypothermic. Endotoxin caused a transient rise in blood glucose in both groups which was associated with a rise in plasma insulin concentration. Blood glycerol levels fell only in starved rabbits, and hydroxybutyrate concentration in both groups following endotoxin treatment. No change in blood pyruvate, lactate, alanine, or acetoacetate level was observed in either group.