Search PubMed⌕ Search

Biomedical subjects

R B Gupta

Publications and source records attributed to R B Gupta.

30 records · Page 2Linked to original sources
PubMedDate not supplied

Formulation, characterization, and in vitro release of glyburide from proliposomal beads.

The objective of our study was to formulate and evaluate proliposomes in the form of enteric-coated beads using glyburide as a model drug. The beads were enteric coated with Eudragit L-100 by a fluidized bed coating process using triethyl citrate as plasticizer. Content uniformity of glyburide was estimated using HPLC analysis of beads dissolved in methanol. These proliposomal beads formed liposomes on disintegration in phosphate buffered saline (pH 7.4), which was confirmed by transmission electron microscopy. The dissolution study of enteric-coated beads exhibited enhanced dissolution compared with pure drug and a marketed product. Liposomes can be successfully prepared for oral administration in the form of enteric-coated beads that may offer a stable system to produce liposomes for oral administration.

Chemistry, Pharmaceutical↗
PubMedDate not supplied

Repeat open intracardiac operation--analysis of 55 patients.

Of the 4170 open intracardiac operations performed at our hospital in the last 6 years, 55 (1.3%) were reoperations. Of these failed valve repairs or valve substitutes formed the major group (58%) and the interval between first and second operation ranged from 6 months to 8 years. There were 4 deaths on table and another 6 patients died during their hospital stay giving an early mortality rate of 18 per cent. There was one late death during a follow-up period of 1 month to 3 years. There was no death due to perioperative bleeding complications. We conclude that it should now be possible to perform reoperations with an acceptable mortality and good late functional results.

Adolescent↗
PubMedDate not supplied

A study of pituitary-thyroid function during exercise in man.

Exercise induced modulations in circulatory T4, T3 and TSH were monitored in 14 healthy euthyroid male volunteers undergoing exercise on a bicycle ergometer at 750 KPM for 20 minutes. TSH response to 100 micrograms TRH was also studied in 4 exercising and 4 resting subjects. Serial blood samples were obtained before, during and after the exercise. Serum T4 exhibited a significant decrease (P less than 0.05) from 9.6 +/- 0.49 microgram/dl (mean +/- SE) to 8.3 +/- 0.47 microgram/dl at 20 min after the termination of the exercise, whereas a significant decrease (P less than 0.01) in T3 levels from 158 +/- 9 ng/dl to 144 +/- 8.2 ng/dl was recorded at 40 min after the termination of the exercise. The basal TSH levels as well as the sensitivity of the pituitary thyroid axis, monitored as overall TSH response, reflected by the sum of TSH values at different time intervals and the maximum rise over the basal levels (delta TSH) remained unaltered after exercise. These observations suggest that hormone secretion by the thyroid and its responsiveness to endogenous TSH are maintained after exercise. The decrease in circulatory T4 and T3 could be due to an increase in degradation of the hormones or may reflect a generalized adaptation phenomenon. The exact mechanism and significance of these alterations remains to be elucidated.

Adult↗
PubMedDate not supplied

Plasma insulin, growth hormone, and blood sugar during exercise in man.

Alterations in plasma immunoreactive insulin (IRI), human growth hormone (hGH) and blood glucose were studied in five male volunteers undergoing exercise for 20 min on a bicycle ergometer at 750 kpm/min. Plasma IRI and hGH levels before exercise were 4.42 +/- 1.35 micro U/ml (mean +/- SE) and 1.94 +/- 0.88 ng/ml respectively. A significant decrease (p less than 0.01) in plasma IRI was observed at 20 min postexercise and remained at lower levels upto 80 min of observations. hGH levels showed significant increase (p less than 0.05) to a mean value of 7.46 +/- 0.71 ng/ml at 20 min of exercise with a peak value of 16.0 +/- 5.04 ng/ml at 20 min postexercise. Sixty min after termination of exercise, hGH levels returned to pre-exercise values. Blood glucose rose progressively with the increase in the duration of exercise and peak levels were recorded at 20 min of exercise. Sixty min after termination of exercise, blood glucose levels returned to pre-exercise values. These observations suggest that exercise stress can lead to a physiological situation in which circulating insulin and glucose are not exclusively dependent on each other.

Adult↗
PubMedDate not supplied

Cholinesterase activity in the great blood vessels of the heart of Pteropus giganteus.

The great thoracic blood vessels associated with the heart of the Indian flying fox -- Pteropus giganteus were studied histochemically. Acetylcholinesterase was used as a histochemical tool for studying the pattern of distribution of ganglia, nerve plexuses, nerve fibres and nerve endings innervating the various layers of the blood vessels. Their role in the regulation of vasodilation and vasoconstriction is discussed.

Acetylcholinesterase↗