q-RASTR modelling for prediction of diverse toxic chemicals towards T. pyriformis.

A series of diverse organic compounds impose serious detrimental effects on the health of living organisms and the environment. Determination of the structural aspects of compounds that impart toxicity and evaluation of the same is crucial before public usage. The present study aims to determine the structural characteristics of compounds for Tetrahymena pyriformis toxicity using the q-RASTR (Quantitative Read Across Structure-Toxicity Relationship) model. It was developed using RASTR and 2-D descriptors for a dataset of 1792 compounds with defined endpoint (pIGC50) against a model organism, T. pyriformis. For the current study, the whole dataset was divided based on activity/property into the training and test sets, and the q-RASTR model was developed employing six descriptors (three latent variables) having r2, Q2F1 and Q2 values of 0.739, 0.767, and 0.735, respectively. The generated model was thoroughly validated using internationally recognized internal and external validation criteria to assess the model's dependability and predictability. It was highlighted that high molecular weight, aromatic hydroxyls, nitrogen, double bonds, and hydrophobicity increase the toxicity of organic compounds. The current study demonstrates the applicability of the RASTR algorithm in QSTR model development for the prediction of toxic chemicals (pIGC50) towards T. pyriformis.

Impact of atmospheric dry deposition of nutrients on phytoplankton pigment composition and primary production in the coastal Bay of Bengal.

Atmospheric deposition of pollutants decreases pH and increases the nutrient concentration in the surface water. To examine its impact on coastal phytoplankton composition and primary production, monthly atmospheric aerosol samples were mixed with coastal waters in the microcosm experiments. These experiments suggested that the biomass of Bacillariophyceae, Dinophyceae and Chlorophyceae were increased and primary production of the coastal waters increased by 3 to 19% due to the addition of aeolian nutrients. The increase in primary production displayed significant relation with a concentration of sulphate and nitrate in the atmospheric aerosols suggesting that both decreases in pH and fertilization enhanced primary production. The impact of acidification on primary production was found to be 22%, whereas 78% was contributed by the nutrient increase. The atmospheric pollution is increasing rapidly over the northern Indian Ocean since past two decades due to rapid industrialization. Hence, it is suggested that the impact of atmospheric pollution on the coastal ecosystem must be included in the numerical models to predict possible changes in the coastal ecosystem due to climate change.

Renal tuberculosis in infancy.

We report a case of congenital renal tuberculosis in a 34-day-old child presenting as severe hematuria. Adequate antitubercular treatment may provide protection to fetus in subsequent pregnancies.

Development and validation of a method for densitometric analysis of berberine in herbal extract and polyherbal formulation.

OBJECTIVE: To develop a new high-performance thin-layer chromatography (HPTLC) method for the quantification of berberine in herbal extract and pharmaceutical dosage form. MATERIALS AND METHODS: The HPTLC was performed on aluminium foil plates coated with 200 µm silica gel 60F(254). Linear ascending development with toluene:ethyl acetate:formic acid:methanol 9:9:3:1 (v/v/v/v) was performed at room temperature (25 ± 2°C) in a twin-trough glass chamber saturated with mobile-phase vapour. Compact bands (R(F) 0.58 ± 0.02) were obtained for berberine. Spectrodensitometric scanning was performed in fluorescence mode at 350 nm. The method was validated for precision, recovery, robustness, specificity, and detection and quantification limits, in accordance with International Conference on Harmonization guidelines. RESULTS: Linear regression analysis of the calibration plots showed a good linear relationship (r(2) = 0.9996 ± 0.0001) between peak area and concentration in the range 10-100 ng/band, respectively. The limits of detection and quantification were 2.8 and 9.3 ng/band. The recovery of the method was 98.5-100.6%. CONCLUSION: The above method was a rapid and cost-effective quality-control tool for routine analysis of berberine in herbal extracts and in pharmaceutical dosage form.

High-q-resolution neutron scattering technique using triple-axis spectrometers.

A new technique is presented that gives a substantial increase in the wavevector q resolution of triple-axis spectrometers by matching the measurement wavevector q to the reflection taua of a perfect-crystal analyzer. A relative Bragg width of deltaq/Q approximately 10(-4) can be achieved with reasonable collimation settings. This technique is very useful in measuring small structural changes and line broadenings that cannot be accurately measured with conventional set-ups, while keeping all the strengths of a triple-axis spectrometer.

Fat, moisture, and ethanol migration through chocolates and confectionary coatings.

The migration of fat, moisture, and ethanol is a common problem with chocolate-coated confectionery products. Migration of one of these components into the coating leads to visual and sensory defects such as sugar or fat bloom, making the product unacceptable to the consumer. The migration rate depends on the structure and composition of the coating. The migration of each of these species can be slowed to a certain extent by proper tempering of the coating, because proper tempering will give a structure that resists migration. In the continuous lipid phase, these chemical species migrate mainly through the liquid portion. Thus, the migration rate depends on the amount of liquid oil present in the product. Migration can be delayed either by reducing the liquid fat content or by immobilizing the liquid phase. The actual mechanisms for the migration processes are speculative, and a more thorough understanding is necessary to better abate quality deterioration. Armed with this understanding, a manufacturer would know a priori the effect of changing the ingredient or process. A few methods for control have been suggested, but have found limited application. Mathematical models have been proposed to predict the migration behavior, but their application is hindered because of the simplified assumptions employed. There is a need for developing better models that combine mass transfer with the phase behavior to be able to accurately predict the migration process. This review discusses the current understanding of fat, moisture, and ethanol migration through chocolate coatings and also includes a brief description of the theoretical aspects governing migration.

Intergeneric protoplast fusion between xylanase producing Bacillus subtilis LYT and Corynebacterium acetoacidophilum ATCC 21476.

Hybrids between a strain of Bacillus subtilis isolated in our laboratory and having the ability to degrade xylan and other complex polysaccharides and Corynebacterium acetoacidophilum, a lysine producer, were prepared by protoplast fusion. Based on distinctive parental biochemical characteristics the fusants were grouped into 9 categories, viz. BC1 through BC9. Three of the hybrids, BC5, BC7a and BC7b, were tested for their ability to produce xylanase and lysine. Both BC7a and BC7b produced xylanase but BC5 did not, however all of them produced lysine albeit to different degrees. These results demonstrate that intergeneric gene transfer takes place through protoplast fusion between these 2 important genera of bacteria and some of the fusants inherit the useful traits of both the parents.