Showing papers by "Badri N. Pandey published in 2009"
TL;DR: The data suggest that Ca-DTPA injection in 232Th-treated animals failed to improve the neurobehaviour of the treated mice, perhaps because Ca- DTPA could not decorporate 232Th or mitigate 232Th -mediated neurochemical changes effectively from/in hippocampus, a brain region implicated in learning and memory response.
Abstract: Purpose: Thorium (232Th), a heavy metal radionuclide that targets the liver and skeleton, has been shown to accumulate in the central nervous system at low levels. The present study was aimed to investigate neurobehavioural and neurochemical changes in mice treated with 232Th at sub-lethal doses.Materials and methods: Swiss albino mice were administered intraperitoneally with thorium nitrate. The chelation-based therapeutic effect of calcium diethylenetriamine pentaacetate (Ca-DTPA) was tested on the 232Th-treated mice. 232Th localisation was determined in brain regions by the Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) method. Achetylcholine esterase (AChE) activity in different brain regions was evaluated to assess the cholinergic function of mice CNS. Oxidative damage was evaluated by assessing the activities of antioxidant enzymes (i.e., superoxide dismutase and catalase) and the level of lipid peroxidation. The neurobehavioural alteration in the treated mice was studied by the s...
24 citations
TL;DR: The results of the study clearly suggested that the apoptosis induced by D7 would involve alteration of MPT, cardiolipin peroxidation, migration of Bax from cytosol to mitochondria, decreased expression of Bcl-2, and release of cytochrome c, indicating oxidative mechanism at the mitochondrial level in the tumor cells.
Abstract: Mitochondria and associated oxidative stress have been shown to play critical roles in apoptotic death induced by various stress agents. Previously, we reported the antitumor property of diospyrin (D1), a plant-derived bisnaphthoquinonoid, and its diethylether derivative (D7), which was found to cause apoptotic death in human cancer cell lines. The present study aims to explore the relevant mechanism of apoptosis involving generation of cellular reactive oxygen species (ROS) by D7 in human breast carcinoma (MCF-7) cells. It was found that while D7 inhibited the proliferation of tumor cells, the associated apoptosis induced by D7 was prevented by treating the cells with N-acetyl-l-cysteine (NAC), an antioxidant, and cyclosporine A (CsA), an inhibitor of mitochondrial permeability transition (MPT). Experiments using suitable inhibitors also demonstrated that D7 could alter the electron flow in mitochondrial electron transport chain by affecting target(s) between complex I and complex III, and indicated the probable site of D7-induced generation of ROS. These results were further supported by confocal microscopic observation on changes in mitochondrial organization and shape in cells treated with D7. Taken together, the results of our study clearly suggested that the apoptosis induced by D7 would involve alteration of MPT, cardiolipin peroxidation, migration of Bax from cytosol to mitochondria, decreased expression of Bcl-2, and release of cytochrome c, indicating oxidative mechanism at the mitochondrial level in the tumor cells.
21 citations
TL;DR: The cytotoxicity of 19 N-aryl-substituted hydroxamic acids has been tested in vitro towards human breast cancer MCF–7 cell lines by MTT assay and 2D-QSAR model reported herein provide interesting insight in understanding hydrophobic, electronic, and structural requirements of antitumor activity among these set of the compounds.
Abstract: The cytotoxicity of 19 N-aryl-substituted hydroxamic acids has been tested in vitro towards human breast cancer MCF–7 cell lines by MTT assay. The IC50 values were found to be in the range from 61.94 to 337.54 μM. A total of 18 out of 19 molecules had higher inhibitory activities than hydroxyurea against MCF–7 cell. Five compounds with IC50 values in micromolar range were 3- to 5-folds more potent than hydroxyurea (IC50=307.15 μM). By partial least squares (PLS) regression, 2D-QSAR model reported herein provide interesting insight in understanding hydrophobic, electronic, and structural requirements of antitumor activity among these set of the compounds. The cross-validated Q2cum values for optimal PLS model of hydroxamic acids is above 0.638 (remarkably higher 0.50), indicating good predictive abilities for log 1/IC50 values of hydroxamic acids (HAs). The k-nearest neighbor molecular field analysis (kNN-MFA) approach was used to generate three-dimensional quantitative structure-activity relationship (3D-QSAR) models for these sets of molecules. Statistically stepwise variable selection k-nearest neighbor molecular field analysis (SW-kNN-MFA) model is comparatively better as compared to the other two (i.e. simulated annealing k-nearest neighbor molecular field analysis, SA-kNN-MFA, and genetic algorithm k-nearest neighbor molecular field analysis, GA-kNN-MFA) with respect to both the internal (q2=0.7461) as well as external (pred_r2=0.6107) model validation and correctly predicts activity of ca. 74.61% and ca. 61.07% for the training and test set, respectively. It uses one steric and one electrostatic fields along with its 3k nearest neighbor (k=3) to evaluate the activity of new molecules. The developed SW-kNN-MFA model field plot indicated that the positive steric and electric potential are favorable for the increase in the activity and hence more bulky substituent at 5-position of phenyl ring connected at amide group and less electronegative substituent at 3-position of phenyl ring connected to carboxyl group are favourable for the increase in the potency of the molecules.
12 citations
Journal Article•
TL;DR: The zooplankton fauna of Kishanganj swamps in relation to certain physico-chemical parameter was studied and rotifers and cladocerans showed negative correlation with pH, sulphate and phosphate while copepods revealed negative correclation with pH and water temperature.
Abstract: The zooplankton fauna of Kishanganj swamps in relation to certain physico-chemical parameter was studied. Out of 28 species recorded, 18 belong to rotifera, 6 to cladocera and 4 to copepoda. The total zooplankton density was more in summer and least in rainy season. The quantitative relationship amongst the group of zooplankton was rotifera > cladocera > copepoda. Zooplankton also comprised of some pollution tolerant species like Brachionus, Keratella and Mesocyclops etc. The rotifers showed negative correlation with pH, sulphate and dissolved oxygen cladocerans showed negative correlation with pH, sulphate and phosphate while copepods revealed negative correclation with pH, sulphate and water temperature.
2 citations
TL;DR: It was interesting to observe that the dose rate determined by chemical dosimetry was well correlated with the number of micro-nucleus formations at different positions of the chamber, suggesting that theNumber of single MN/cells could be better biomarkers for determining the doses.
Abstract: The aim of the present study is to determine the dose distribution in gamma irradiation chambers by chemical dosimetry and to establish its correlation with biological dosimetry. The dose-distribution studies of these two gamma chambers show that compared to the center point of the chambers, the dose rate was 17%-22% higher at the circumference. Moreover, the dose rate was 12%-18% lower at the bottom and top positions compared to the center point. It was interesting to observe that the dose rate determined by chemical dosimetry was well correlated with the number of micro-nucleus (MN) formations at different positions of the chamber. Our results suggest that the formation of the single MN/cell was better correlated with the dose rate than the double MN/cell, suggesting that the number of single MN/cells could be better biomarkers for determining the dose rate. These results provide a correlation between chemical and biological dosimetry, which may have relevance in the development of better bioassay techniques for radiation exposure.
2 citations