Transcriptional specificity after mycobacteriophage I3 infection

Transcriptional regulation following mycobacteriophage I3 infection has been investigated. For this purpose, RNA polymerase mutants (rif) of host bacterium, Mycobacterium smegmatis have been isolated and characterised. Phage growth inrifs and rifr cells in presence of rifampicin revealed the involvement of host RNA polymerase in phage genome transcription. This was confirmed by studies onin vivo RNA synthesis as well as by direct RNA polymerase assay after phage infection. Significant stimulation in RNA polymerase activity was seen following phage infection. The maximal levels were attained in about 60 min post infection and maintained throughout the phage development period. The stimulation of polymerase activity was most pronounced when the phage DNA was used as the template. RNA polymerases from uninfected and phage-infected Mycobacterium smegmatis have been purified to homogeniety. The enzyme purification was accomplished by a rapid procedure utilising affinity chromatography on rifampicin-Sepharose columns. Subunit structure analysis of the purified RNA polymerase from uninfected and phage-infected cells showed the presence of α ,β , β ' and σ subunits similar to the other prokaryotic RNA polymerases. In addition, a polypeptide of 79, 000 daltons was associated with the enzyme after phage infection. The enzymes differed in their properties with respect to template specificity. Phage 13 DNA was the preferred template for the modified RNA polymerase isolated from infected cells which may account for the transcriptional switch required for phage development

Requirement for calcium ions in mycobacteriophage I3 DNA injection and propagation

Ca2+ ions are absolutely necessary for the propagation of mycobacteriophage I3 in synthetic medium. These ions are required for successful infection of the host and during the entire span of the intracellular development of the phage. A direct assay of the phage DNA injection using 32[p] labelled phage, shows that Ca2+ ions are necessary for the injection process. The injection itself is a slow process and takes 15 min to complete at 37°. The bacteria infected in presence of Ca2+ tend to abort if the ions are subsequently withdrawn from the growth medium. The effect of calcium withdrawal is maximally felt during the early part of the latent period; however, later supplementation of Ca2+ ions salvage phage production and the mature phage progeny appear after a delayed interval, proportional to the time of addition of Ca2+

Isolation, screening of Aspergillus flavus and its production parameters for á- amylase under solid state fermentation

The amylase producing fungi were isolated from spoiled fruits, vegetables and soil, in and around Bangalore, Karnataka, India. The isolates were identified and five fungal species were screened. The best amylase producer among them, Aspergillus sp was selected for enzyme production by both sub merged fermentation using mineral salt medium (MSM) and solid state fermentations using wheat bran as a solid substrate. The various parameters influencing solid state fermentation were optimized. The most important factors are such as pH, incubation temperature, incubation period, carbon sources, nitrogen sources and moisture content. The maximum amount of enzyme production was obtained when solid state fermentation was carried out with soluble starch as carbon source and beef extract (1% each) as nitrogen source, optimum conditions of pH 7.0, an incubation temperature of 25 (±2) °C, incubation time 96 h and 62% moisture content

A preliminary pharmacognostical study on leaves and flowers of Michelia champaca L. Magnoliaceae

The present investigation was conducted to establish pharmacognostical profile for the leaves and flowers of Michelia champaca L. (Magnoliaceae) in order to establish its complete profile to aid in its identification and avoid confusion in taxonomic level for different species of the same genus. The study included macroscopical, organoleptical, microscopical and preliminary phytochemical analysis of the leaves and flowers. The study of the organoleptical evaluation revealed the presence of colour, odour and texture. The microscopic analysis showed thedifferences in cell structures, arrangement and shape of leaves and flowers. The physical characters of various solvent extracts showed the presence of colour, odour and consistency of the powdered leaves and flowers. Finally, the preliminary phytochemical analysis confirmed for the presence of alkaloids, saponins, tannins, glycosides, carbohydrates, amino acid, flavonoids and sterols in both leaves and flowers. The present findings may be used to establish the authenticity of leaves and flowers of Michelia champaca L. for their proper identification and standardization in order to collect raw plants for the preparation of herbal drugs

New spectrophotometric method for the determination of flutamide in pharmaceutical preparations

A sensitive and simple spectrophotometric method for the determinations of reduction product of flutamide (FLA) is described. The method is based on the interaction of diazotized flutamide reduction product with N-(1-naphthyl) ethylenediamine dihydrochloride (NEDA) in neutral or resorcinol (RSL) in alkaline medium. Absorbance of the resulting chromophores is measured at 525 or 480 nm, respectively, and is stable for at least 7 days. The two coupling reagents are applied successfully for the determination of FLA in tablets. The common excipients used as additives in pharmaceutical preparations do not interfere with the determination. Results from the analysis of pure FLA and its commercial tablets by the proposed methods agree well with the reported method. (C) 2000 Elsevier Science B.V. All rights reserved

Antimicrobial effect of Lagenaria siceraria (Mol.) Standley, against certain bacteria and fungal strains

This study was performed to evaluate the antibacterial and antifungal potency of Lagenaria siceraria (Mol.) Standley, commonly known as bottle gourd belonging to the family Cucurbitaceae. Petroleum Ether, Chloroform, Methanol, Absolute alcohol and Water showed a majority of the compound including Steroids, Alkaloids, Tannins, Flavonoids, Lactones and Carbohydrates. All the five extracts were prepared by using soxhlet apparatus and the extracts showed moderate to potent antimicrobial activity against the bacterial strains: Escherichia coli, Enterococcus faecalis, Klebsiella pneumonia, Salmonella typhi, Staphylococcus aureus and antifungal strains: such as Aspergillus flavus, Aspergillus oryzae and Trichoderma harzianum

Study on self-medication among 2nd year medical students

Background: Self-medication is use of medicines by individuals to treat self-recognized symptoms and illness. Self-medication is a common type of self-care behavior in the general public, but medical students differ in such practice, as they have knowledge about drugs and diseases.Methods: The present study involved 100 2nd year final term medical students in “Shivamogga Institute of Medical Sciences,” Shivamogga, Karnataka. Study was questionnaire based, and the results were analyzed by descriptive statistical methods.Results: In our study, 57% were female, and 43% were male. About 60% had knowledge about over the counter (OTC) drugs and considered Ayurveda drugs also OTC drugs. 25% considered self-medication entirely safe, whereas 61% considered self-medication have advantages. Self-medication was preferred by 72% as they felt that there is no need to consult health care professionals for a simple ailment. Self-medication was practiced by 62% students, among which 86% were appropriate, and 48% among them utilized knowledge from previous consultation. In 28% fever was the most common condition and paracetamol was the most commonly used drug.Conclusions: Self-medication was widely practiced among the students. They had good knowledge of OTC drugs. The practice of self-medication was almost appropriate. In general self-medication must be accompanied by appropriate information. Educating benefits and risks of self-medication is very much needed for medical students and the public now a day

Biology of squids

This section is. based on the data collected in the squid jigging survey made by two vessels, M.F.V. Matsya Sugandhi and M.V. Blue Fin on the southwest coast of India during the 9-month period from June 19&& to February 19&9. The data were collected onboard by the scientists of CMFRI who partici;>ated in the survey. Three species of squids were jigged during the survey, and to understand some aspects of the biology of each of these species a general idea about their distribution and Telative abundance in space and time is necessary. For this' purpose, a one-degree square where jigging was done during the period is taken as a unit area

Influence of Environmental Factors on Growth Rate of Crassostrea madrasensis (Preston) in Suspended Culture

Growth response of Crassostrea madrasensis to varying environmental factors in the Mulki estuary of Karnataka was investigated from April 2004 to March 2005. Temperature, salinity, pH, particulate organic matter (POM), particulate inorganic matter (PIM), total particulate matter (TPM) and chlorophyll a (Chl a) levels were correlated with growth in shell length. Marked seasonal patterns in growth rate were observed in relation to changes in environmental factors. Growth curve indicated a rapid phase (16.21±1.2 mm month-1) initially (May-June) followed by a slow phase (0.8±0.52 mm month-1) coinciding with the drop in salinity (August-September). Considering the temporal variations of environmental factors, their influence on growth rate was analysed seasonally. The growth rate was significantly correlated with Chl a concentrations in all the seasons. A pronounced seasonal cycle was noticed in Chl a levels resulting from blooms in pre-monsoon (April-May) and post-monsoon (October) seasons