Search PubMed⌕ Search

Biomedical subjects

G De Ponte

Publications and source records attributed to G De Ponte.

7 recordsLinked to original sources

Effect of swimming on protein degradation: 3-methylhistidine and creatinine excretion.

The effect of 5-km noncompetitive swimming (moderate exercise) and 2-km competitive speed swimming (intensive exercise) on protein breakdown was studied in a group of young male volunteers (16-20 years old) who followed a 3-MH-free diet throughout the study. Urinary 3-MH and creatinine were determined over a period of 24 and 48 hr as an index of protein degradation. Basal 3-MH levels in the two groups of swimmers were 2.85 and 3.07 mumole X kg-1 X day-1. Mean rates of 3-MH excretion were, respectively, 1.54 and 1.94 mumole X kg-1 X day-1 for the 48 hr after moderate exercise and the 24 hr after intensive exercise. The decrease in 3-MH urinary excretion was still evident when calculated as the urinary 3-MH-to-creatinine ratio.

Adolescent↗

Increased myofibrillar protein catabolism in duchenne muscular dystrophy measured by 3-methylhistidine excretion in the urine.

Myofibrillar protein catabolic rate was calculated in 50 young patients with Duchenne muscular dystrophy from the amount of 3-methylhistidine excreted in the urine, and was found to be about seven times that of a control series, expressed as the percentage of myofibrillar protein catabolized per day. This wastage of myofibrillar protein is a consequence of Duchenne muscular dystrophy and inhibition of protein degradation appears to be one possible approach in the treatment of this disease.

Child↗

Decrease in N-acetyl-L-aspartic acid in brain of myodystrophic mice.

Brain tissue from myodystrophic mice (male 129/ReJ-dy and female 129 B6F1/J-dy) was examined to determine whether CNS abnormalities accompany the known muscular defects. Brain N-acetyl-L-aspartate, aspartate, and glutamate were significantly lower than in brain from control mice. These amino acids are only slightly reduced in brains of female dystrophic mice.

Animals↗

Content of methylhistidines in normal and pathological human skeletal muscles.

The content of 3-methylhistidine (3-MH) and 1-methylhistidine (1-MH) was measured in muscle biopsy specimens from 13 normal controls, 19 patients with Duchenne muscular dystrophy, 8 limb-girdle disease patients, and 23 disease controls with different forms of muscular pathology. 3-MH and 1-MH concentrations in normal human muscle did not appear to be influenced by sex, body weight, and age, at least for subjects in the 10--60 year age group examined. Skeletal muscle 1-MH levels did not significantly differ from mean control values in any of the pathologies investigated. In the patient population examined, the mean 3-MH level per unit of noncollagen protein (NCP) was significantly lower than normal in Duchenne dystrophy only, the reduction being related to disease severity. The significantly lower concentrations of 3-MH in muscle of Duchenne patients indicate the importance of measuring 3-MH in diseased muscle to obtain reliable estimates of the myofibrillar protein catabolic rate.

Adolescent↗