Biomedical subjects

S Leslie

Publications and source records attributed to S Leslie.

3 recordsLinked to original sources

PubMed1989

Cathepsin B, D and H activities in muscles of chicks of fast and slow growing strains: effect of age and diet.

1. Activities of cathepsins B, D and H were measured in leg and breast muscles of fast growing (broiler) and slow growing (layer) chicks at eight time intervals between 1 and 29 days of age. 2. These enzyme activities were also measured in muscles from fast and slow growing chicks given a low protein (125 g/kg crude protein) diet between the ages of 17 and 24 days. 3. Activities of none of these cathepsins differed greatly between muscle type or strain of chick. However in both strains of chick cathepsin D and H in muscles significantly decreased with increasing age (muscle size) of the chick. Cathepsin D activity also increased when muscle proteolytic rates were increased by feeding a low protein diet. This latter effect was significant only in the muscles of fast growing chicks. 4. The results suggest that lysosomal proteases are not responsible for the differences in muscle protein degradation and growth between fast and slow growing strains of chicks, or between muscle types in the chick.

Aging↗

PubMed1988

Muscle growth and protein degradation during early development in chicks of fast and slow growing strains.

1. Growth of breast and leg muscles and excretion of N tau methyl histidine in layer (slow growing) and broiler (fast growing) chicks were measured at five time intervals between 2 and 33 days of age. 2. The results indicate that muscles of the broiler chick grow faster than in layer chicks and that breast muscles of both strains grow faster than leg muscles in the first 2 weeks after hatching. 3. N tau methyl histidine excretion by layer chicks is higher than that by broilers relative to body weight, musculature and relative maturity at all ages examined. 4. The results suggest that faster growth of muscles is accompanied by a lower rate of protein degradation although at ages of less than 2 weeks differences in protein synthesis rates may also contribute to muscle growth.

Aging↗

PubMed1986

The Contin delivery system: dosing considerations.

The combination of hydrated cellulose with higher aliphatic alcohol forms the basis of the Contin delivery system, used in the development of tablet forms of sustained-release aminophylline, theophylline, morphine, and other drugs. Extensive clinical and pharmacokinetic evaluation of Uniphyl (anhydrous theophylline) tablets, 400 mg, shows that once-daily morning dosing is at least equivalent to twice-daily administration of theophylline. Ingestion of the once-daily product with a high-calorie-high-fat meal in volunteers increased the absorption of theophylline without accompanying "dose-dumping." Extensive pharmacokinetic evaluation in patients with food intake not controlled has yielded bioavailability comparable to that of twice-daily theophylline. Ongoing research suggests that evening administration of Uniphyl tablets may represent a rational dosing schedule for patients with asthma who often exhibit increased bronchoconstriction in the morning. In these studies patients demonstrate improved pulmonary function in the morning compared with use of twice-daily theophylline when once-daily Uniphyl is administered in the evening. Thus, evening administration of once-daily theophylline may block the morning dip in lung function commonly seen.

Asthma↗