Phenamine sterotypy as a drug-induced model of psychopathology

Stereotype movements in cats following the administration of bid dosages of phenamine is accompanied by crude disorders of conditioned avoidance with an increase of intrasignal reactions, a weakening of differentiated inhibition and an inhibition of avoidance responses due to low frequency irritation of the caudate nucleus. Caffeine even in large dosages does not possess such properties. Phenamine as in caudectomia decreases the amount of monomodel neurons in the neocortex, as well as group postdischarges in the caudate response of neurons. It is assumed that many indices of phenamine stereotypicity, as a possible model of psychopathology, may be explained by disturbances of the filtering and retention functions of the caudate nucleaus.     

Expression of functionally active hyman cytochrome P-450c21 (CYPXXIA2) in Escherichia coli and single-stage purification of it using metal-affinity chromatography

Active human cytochrome P-450c21 was expressed in Escherichia coli and purified to homogeneity. To increase expression, cDNA encoding for the N-terminal fragment of cytochrome P-450c21 was modified. Four histidine codons were added to cDNA encoding for the C-terminus of the protein; thus, recombinant protein could have been rapidly and effectively purified by metal-affinity chromatography. Modified human cytochrome P-450c21 was expressed (40-50 nmoles/l of culture according to spectrophotometry) which was able to bind to bacterial membrane. Modifications of N- and C-terminal regions of cytochrome P-450c21 did not change Km and Vmax for hydroxylation of progesterone and 17 alpha-hydroxyprogesterone in reconstituted system. Recombinant cytochrome P-450c21 was purified to apparent homogeneity from Escherichia coli membrane extract by metal-affinity chromatography. Purified cytochrome P-450c21 migrates as a single 54 kD band on polyacrylamide gel and exhibits type I spectral changes during interaction with progesterone and 17 alpha-hydroxyprogesterone. Activity of purified cytochrome P-450c21 was reconstituted with mouse liver microsomal NADPH-cytochrome P-450-reductase and NADPH-regenerating system. Purified enzyme had Km 12.2 and 3.21 microM and Vmax 192.9 and 198 nmoles/min/nmole of P-450c21 for 17 alpha-hydroxyprogesterone and progesterone, respectively. According to titration spectra, dissociation constants for progesterone and 17 alpha-hydroxy-progesterone were 14.7 and 31.1 microM, respectively.     

Protective effect of a tetracycline-sensitive strain of Escherichia coli on the growth of a tetracyclic-resistant strain in the presence of tetracycline in a coculture

The addition of tetracycline to a culture of a tetracycline-sensitive strain of Escherichia coli leads to the appearance in the medium of a chemical compound (or compounds) that in part relieve the inhibition of growth of a tetracycline-resistant strain by a high concentration of the antibiotic. An increase in the growth rate can be as high as 50%.     

The evaluation of the total toxicity of heavy metals based on the luminescence bacterial test

Antibacterial properties of bacteria of genera Escherichia, Enterococcus, Bacillus, Lactobacillus, Bifidobacterium isolated from different parts of gastro-intestinal tract of the healthy milk-fed and weanling calves were studied against test-bacteria, microorganisms of the Escherichia genus with and without pathogenic factors as well as the genera Klebsiella, Enterobacter, Proteus, Salmonella, Staphylococcus representatives that had been isolated from healthy and sick calves. Certain tolerance was determined between the groups of bacteria under study and only some strains of lactobacteria and bifidobacteria showed selective antibacterial action on pathogenic and conditionally pathogenic microorganisms, thus stabilizing intestinal microbiota in the gastro-enteric tract of calves.     

Experimental and clinical study of antibiotics administered intravitreally in endophthalmitis

The concentrations of gentamicin and cefotaxime (claforan) in the humor of the anterior chamber and vitreous body of the eye were estimated in the study on the pharmacokinetics of the antibiotics in rabbits. The antibiotics were administered intravitreally in single doses. It was shown that the residence time of the antibiotics in the therapeutic concentrations in the eye cavity was 48 hours. Cefotaxime proved to be the most efficient agent in the prevention and treatment of postoperative endophthalmitis.     

The complex forensic medical study of the bony remains from a burial long ago]

A cross-sectional study was conducted in a randomly selected village of Rangpur district from June '94 to May '95. Serum from 1000 human subjects irrespective of age and sex were screened for hepatitis B surface antigen (HBsAg). Among the respondents 661 were male and 339 female. The overall seroprevalence of HBsAg was 6.4%. It was 6.66% in male and 5.89% in female. Age, sex, religion, income, occupation, education and marital status did not show any relationship with HBsAg status. Among 64 sero-positive cases, 16 (25%) had no history of exposure to known risk factors and 48 (75%) had one or more exposure to known risk factors (p < 0.05). This study did not depict the national scenario. Well designed studies with more sensitive serological methods are recommended to get the epidemiological information of hepatitis B virus (HBV) infection in our community.