Preparation and evaluation of calcium silicate based floating microspheres of amoxicillin.

The aim of the present study was to prepare and evaluate floating microspheres consisting of (i) calcium silicate (CS) as porous carrier; (ii) famotidine and (iii) hydroxypropyl methylcellulose (HPMC) and ethylcellulose (EC) as polymers. The floating microspheres were evaluated for particle size, micromeritic properties, percent drug content, in vitro floating behavior, and in vitro drug release. The percentage yield of floating microspheres of formulations (AM1 to AM9) was found to be in the range of 78.21 ± 1.09 to 93.56 ± 2.79 %. Percentage drug content of formulations (AM1 to AM9) were found in the range of 79.89 ± 2.19 % to 87.74 ± 1.24 %. In Vitro Buoyancy percentage of the microspheres was found to be 98.75±3.62 At pH 1.2, drug release from floating microsphere containing amoxicillin formulation AM4 was found to be 98.87 ± 0.67 % at the end of 12 hr. While at pH 7.4, Formulation AM4 released 99.23 ± 0.94 % of drug at 12 hr respectively. The SEM photographs of formulation AM4 showed that the fabricated microspheres were spherical with a smooth surface and exhibited a range of sizes within each batch. The results suggested that Calcium Silicate is a useful carrier for the development of floating and sustained release preparations.

Interaction of muscle relaxant effect of gallamine with ethanol: in vivo mammalian model.

Ethanol produces alterations in muscular contraction and neuromuscular function both in vitro and in vivo in mammalian and amphibian tissues in dose dependent manner. It is not very well known whether gallamine, a commonly used muscle relaxant produces any interaction with ethanol. Hence in the present study, interactions of ethanol with gallamine are undertaken using rabbit head drop method. The latency time to produce head drop by gallamine in the absence and presence of ethanol (dose which produce ataxia) was insignificantly different (P > 0.05). It may be due to fact that ataxic dose may not be affecting neuromuscular transmission a significant manner. It, therefore, does not warrant to adjust the dose of gallamine in alcoholic persons.

Interrelationship between tumour virus receptors, A and C, coded by host cell genes in fowl.

Bryan Standard strain of Rous Sarcoma Virus (BS-RSV) of subgroup A and pseudotype of Bryan high titre RSV(RAV-49) of subgroup C and an equal mixture of subgroup A and subgroup C virus were inoculated to 11-day old embryos of white leghorn (WL), Australorp (AL) and f1 and f2 generations of crosses between WL and AL breeds of fowl to detect and estimate the interrelationship between tumour virus receptor coding host cell genes of tva and tvc loci. Linkage values estimated on a pooled sex basis were 0.08 +/- 0.03 and 0.10 +/- 0.03 for WL and AL breeds respectively and 0.09 on pooled breed basis. This clearly indicates that the tva and tvc loci are indeed closely linked in WL and AL breeds of fowl and supports the concept of using subgroup C virus to raise stocks resistant to subgroup A virus infection.

Expression of tumour phenotypes, hatchability and liver tumour mortality in two routes of inoculation in fowl.

A total of 350 and 200 eleven-day-olc embryos (pooled breeds) of twelve hatch replicates were inoculated with pseudotype of Bryan high titre, RSV(RAV-49) of subgroup C viz CAM (chorioallantoic membrane) and YS (yolk sac) route, respectively. An increase in hatchability (about 16%) and decrease in the incidence of CAM(+) [71%] and LT(+) [47%] phenotypes was noticed when inoculation was done via YS route as compared to the inoculation via CAM routes. A delay in LT(+) mortality was also recorded in YS route of infection. Chi-square analysis within a route basis indicated highly significant contingency (P < 0.01) in association of CAM infection phenotypes and LT incidence phenotypes for CAM route of infection in contrast to the YS route of infection.

On mechanism of action of ethanol-induced contraction of frog rectus abdominis.

Ethanol in low doses (0.5 to 4 M) causes contraction of isolated frog rectus abdominis muscle. Higher concentration did not produce any further increase in maximum response. Pretreatment with dantrolene produced partial but equal inhibition of acetylcholine (Ach) induced as well as ethanol-induced contraction in equieffective doses. Pretreatment with pancuronium produced right and downward shift of ethanol induced contraction. Pretreatment with succinylcholine produced persistent contraction of tissue and this response remained unaffected on subsequent treatment with Ach as well as ethanol. Pretreatment with hemicholinium abolished ethanol induced contraction, although tissue remained viable as confirmed on addition of Ach. The contraction induced by ethanol decreased on pretreatment with dantrolene as well as in Ca2+ free ringer. The results indicate that ethanol induced contraction may be due to release of Ach or Ach like neurotransmitter at neuromuscular junction and calcium acts as mediator to produce these effects.

On the contribution of height to predict lung volumes, capacities and diffusion in healthy school children of 10-17 years.

Lung volumes, capacities, diffusion and alveolar volumes with physical characteristics (age, height and weight) were recorded for 186 healthy school children (96 boys and 90 girls) of 10-17 years age group. The objective was to study the relative importance of physical characteristics as regressor variables in regression models to estimate lung functions. We observed that height is best correlated with all the lung functions. Inclusion of all physical characteristics in the models have little gain compared to the ones having just height as regressor variable. We also find that exponential models were not only statistically valid but fared better compared to the linear ones. We conclude that lung functions covary with height and other physical characteristics but do not depend upon them. The rate of increase in the functions depend upon initial lung functions. Further, we propose models and provide ready reckoners to give estimates of lung functions with 95 per cent confidence limits based on heights from 125 to 170 cm for the age group of 10 to 17 years.

Organ weights in autopsy cases from an urban apex hospital.

The available limited anatomical and physiological data have been compiled for Indian adult as a part of ongoing efforts in the country to formulate an Indian Reference Man for radiation protection purposes. The parameters included weight, height, body surface area, weight of various organs (brain, heart, kidney, lung, liver etc.), total body water, extra-cellular water, blood volume, specific gravity, total lung capacity, vital capacity etc. The data have been drawn from post-mortem studies (566 males and 185 females) and other data from published work on 433 healthy male and 137 female volunteers. Data gaps have been filled by the method of pooling wherever necessary. This paper presents the intercomparison of the present data with the data available from other sources. The data from various Indian sources indicate a similar trend. However, a significant difference (P less than 0.01) was observed in organ weights and total body weights, in comparison to the Bhabha Atomic Research Centre (BARC) values. The present data are not comprehensive enough to suggest definitive norms of the Indian Reference Man.

Effect of alcohols and their potentiating responses on acetylcholine induced contractures on frog rectus abdominis.

Ethanol, propanol and butanol cause contraction and potentiate the responses of acetylcholine (Ach) on frog's rectus muscle. These actions are minimum with ethanol and maximum with butanol. Various drugs acting at different levels of neuromuscular transmission inhibited the responses of alcohol itself and also its potentiating responses of Ach. The results show that these effects are partly due to enhanced release of Ach at neuromuscular junction and partly due to release of sarcoplasmic calcium suggesting that more than one mechanism may be responsible for these actions.

Triceps skinfold thickness in adolescents.

The triceps skinfold thickness (TSF) was measured in 1000 healthy adolescents aged 11 to 18 yr. Measurements were made with the Standard Harpenden skinfold caliper. Females at all ages studied had thicker skinfolds than their male counterparts. Significant differences in skinfold fat were observed between the high and low socio-economic groups, in both sexes. TSF thickness among girls showed a steady gain throughout adolescence. In boys however, there was a dip in TSF followed by a slow rise, the final thickness being somewhat lower than the prepubertal value. TSF was found to have no correlation with height but good positive correlation with weight and wt/ht2 (body mass index). Hence it may be regarded as a reliable indicator of obesity in this age group, where variable pubertal growth makes nutritional assessment difficult.

Some pharmacological actions of the essential oil of Blumea membranacea.

The essential oil obtained from the plant Blumea membranacea produced a marked and long lasting fall in blood pressure in anaesthetized dogs. The oil exerted a direct depressant action on frog heart and spasmolytic effect on rabbit ileum. It also depressed the conditioned avoidance response, adversely affected rotarod performance and potentiated the pentobarbitone induced hypnosis in rats.