Terbutaline transdermal delivery: preformulation studies and limitations of in-vitro predictive parameters.

A transdermal dosage form of terbutaline may be useful to prevent nocturnal wheezing by providing prolonged duration of action. It will also improve patient compliance and bioavailability. Controlled input of the drug would be an additional advantage as this will reduce the intersubject variability.

HLA phenotype frequencies in pulmonary tuberculosis.

Susceptibility and/or immune response to tuberculosis may or may not be associated with particular histocompatibility leucocyte antigen (HLA) phenotype frequencies. The present study was undertaken to north eastern Indian population to verify any association between HLA phenotypes and immune response to mycobacterial antigen. HLA-typing was done in 60 well Tarasaki trays and T-cell subsets in each group were measured using Ficoll-hypaque nylon wool columns and dynabeads (M-450).

Effect of formulation and processing factors on the characteristics of biodegradable microcapsules of zidovudine.

Biodegradable microcapsules of zidovudine (AZT) were prepared using poly-(lactide/glycolide) by the solvent evaporation technique. The objective of this project was to focus on the effect of several formulation and processing factors on the efficiency of encapsulation, surface morphology, and drug release profiles. When the drug was incorporated as powder or as aqueous suspension containing a high amount of insoluble particles, to the organic phase the surface of the microcapsules was appeared to be wrinkled.

Effect of tablet integrity on the dissolution rate of sustained-release preparations.

The objective of this study was to evaluate the effect of tablet integrity on the dissolution rate. The model drug used for this study was aspirin. A dissolution study was performed with three commercially-available aspirin tablets (ZORprin, Bayer 8-h aspirin and Bayer aspirin), two of which were sustained-release tablets.

Preparation of biodegradable microcapsules containing zidovudine (AZT) using solvent evaporation technique.

Sustained release biodegradable microcapsules of AZT were prepared using different concentrations of copolymer of poly(lactic/glycolic) acid (PLGA 50:50 and PLGA 90:10). Solid microcapsules were collected following the complete evaporation of the solvent. The yield of microcapsules was increased two fold with a two-fold increase of the polymer concentration.

Holliday junction resolvases encoded by homologous rusA genes in Escherichia coli K-12 and phage 82.

The RusA protein of Escherichia coli is an endonuclease that can resolve Holliday intermediates and correct the defects in genetic recombination and DNA repair associated with inactivation of RuvAB or RuvC. The structure of the rusA gene, its organisation in the genome, and its interaction with the Ruv and RecG proteins have been investigated. Recombinant plasmids carrying rusA were identified by their ability to make ruv mutants resistant to UV light.

The disposition kinetics and residues of fenvalerate in tissues following a single dermal application to black Bengal goats.

The disposition kinetics of fenvalerate were studied in goats after dermal application of 100 ml of 0.25% (w/v) solution. The insecticide persisted in the blood for 72 h.

Distribution of HLA antigens in Indian Gurkha population.

Fifty unrelated Indian Gurkha of Nepalese origin were studied to analyse the HLA antigen profile and their relation with other populations. Haplotype B35-Cw4 occurred with highest incidence and significant positive linkage disequilibrium in Gurkhas. Haplotype A10-B8 which occurs with the highest frequency in north Indians was also observed to occur with significant positive linkage in Gurkhas.

Subacute toxicity of fenvalerate in broiler chicks: concentration, cytotoxicity and biochemical profiles.

Subacute toxicity study of fenvalerate was carried out in broiler chicks after oral administration @ 525.6 mg/kg once daily for 28 days. The blood concentration of fenvalerate following 1 day post-administration (pd) was 39.

Resolution of Holliday intermediates in recombination and DNA repair: indirect suppression of ruvA, ruvB, and ruvC mutations.

The ruvA, ruvB, and ruvC genes of Escherichia coli provide activities that catalyze branch migration and resolution of Holliday junction intermediates in recombination. Mutation of any one of these genes interferes with recombination and reduces the ability of the cell to repair damage to DNA. A suppressor of ruv mutations was identified on the basis of its ability to restore resistance to mitomycin and UV light and to allow normal levels of recombination in a recBC sbcBC strain carrying a Tn10 insertion in ruvA.

High-performance liquid chromatographic determination of perphenazine in plasma.

A reversed-phase high-performance liquid chromatographic (HPLC) method for the analysis of perphenazine in rabbit plasma was developed. Amitriptyline HCl was used as the internal standard. The chromatography was performed using a Microsorb-CN column; the mobile phase consisted of 85:15 methanol/0.

Freeze-fracture electron microscopic and osmotic water permeability studies of epidermal lipid liposomes derived from stratum corneum lipids of porcine epidermis.

Freeze-fracture electron microscopic studies revealed that the liposomal membrane morphology was intact before and after osmotic treatment. This finding suggested that water leakage from the liposomes was not due to fusion of two or more lipid vesicles, but rather to the osmotic salt effect. A stop-flow spectrophotometric study revealed that epidermal lipid liposomes derived from stratum corneum lipids of porcine skin underwent increases of the absorbances with decreases of volume of the vesicles.

Pharmacokinetics of oxytetracycline in presence of calcium gluconate in goats.

The concentration of oxytetracycline (OTC) in plasma, after single dose i.v. administration at 10 mg kg-1, was determined during pre and post induced-hypercalcemia in goats.

Electron microscopic study of the polymyxin treated Vibrio cholerae cells.

Polymyxin B produces dose dependent changes in the surface topography of pathogenic Vibrio cholerae cells. The susceptibilities of various vibrio strains to PB are also studied through analytical techniques. Statistical analysis shows significant differences among the four vibrios with regard to their sensitivities to PB, the classical strains being the most sensitive.

Electron microscopic study of the polymyxin treated goat erythrocytes.

Polymyxin B produced dose dependent changes in the surface topography of the goat erythrocyte cells. Transformation from the normal biconcave discs through crenated structures to the final rounded or spherical shape was recorded by scanning electron microscopy. A maximum of three to four crenations per cell was recorded corresponding to a polymyxin dose of 15.

The polymyxin sensitivity and the phosphatidyl ethanolamine content of the Vibrio cholerae membranes.

The phospholipid composition of three different strains of Vibrio cholerae was determined by quantitative two-dimensional thin-layer chromatography. The polymyxin sensitivity of the whole organisms or of the liposomes derived from the total phospholipids of these organisms depended solely on the phosphatidyl ethanolamine content of the system concerned and could be quantitatively related by the equations Y1 = 1.074 X1 - 9.