http://nopr.niscair.res.in/handle/123456789/3476 Search the Channel search http://nopr.niscair.res.in/simple-search http://nopr.niscair.res.in/handle/123456789/3636 Title: Biological monitoring of lead and cadmium in human hair and nail and their correlations with biopsy materials, age and exposure <br/> <br/>Authors: Mehra, Rita; Juneja, Meenu <br/> <br/>Abstract: Hair and fingernails of exposed and unexposed subjects were analyzed for their lead (Pb) and cadmium (Cd) contents by atomic absorption spectrophotometer with graphite furnace and air-acetylene flame. Hair and nail Pb concentrations in occupationally exposed subjects ranged between 1.020-409.726 and 8.130-765.306 µg/g and in environmentally unexposed subjects 0.123-25.160 and 1.076-65.613 µg/g, respectively. Similarly, hair and nail Cd concentrations in occupationally exposed subjects ranged between 0.014-22.086 and 0.214-35.714 µg/g and in environmentally unexposed subjects 0.113-1.627 and 0.028-8.108 µg/g, respectively. A significant correlation was observed between Pb hair and nail concentrations in exposed subjects at P<0.05, as compared to unexposed subjects and Cd hair and nail in exposed, as well as unexposed subjects. With respect to exposure, levels of Pb in hair and nails were found to be significant in exposed subjects, compared to unexposed ones and levels of Cd were significant only in nails of exposed ones. With respect to age, no significant correlation was found between hair and nail Pb and Cd concentrations in both exposed and unexposed subjects. <br/> <br/>Page(s): 53-56 http://nopr.niscair.res.in/handle/123456789/3635 Title: Evidence for the presence of a critical histidine residue at the active site in glyceraldehyde-3-phosphate dehydrogenase of Ehrlich ascites carcinoma cells <br/> <br/>Authors: Ghosh, Swapna; Ray, Manju; Ray, Subhankar <br/> <br/>Abstract: Ehrlich ascites carcinoma (EAC) cell glyceraldehyde-3-phosphate dehydrogenase (GA3PD) (EC. 1.2.1.12) was completely inactivated by diethyl pyrocarbonate (DEPC), a fairly specific reagent for histidine residues in the pH range of 6.0-7.5. The rate of inactivation was dependent on pH and followed pseudo-first order reaction kinetics. The difference spectrum of the inactivated and native enzymes showed an increase in the absorption maximum at 242 nm, indicating the modification of histidine residues. Statistical analysis of the residual enzyme activity and the extent of modification indicated modification of one essential histidine residue to be responsible for loss of the catalytic activity of EAC cell GA3PD. DEPC inactivation was protected by substrates, D-glyceraldehyde-3-phosphate and NAD, indicating the presence of essential histidine residue at the substrate-binding region of the active site. Double inhibition studies also provide evidence for the presence of histidine residue at the active site. <br/> <br/>Page(s): 7-13 http://nopr.niscair.res.in/handle/123456789/3634 Title: Transport studies through liquid membranes of ciprofloxacin and norfloxacin <br/> <br/>Authors: Nagappa, A N; Kole, P L; Pandi, P V; Patil, R T <br/> <br/>Abstract: Ciprofloxacin and norfloxacin, the widely used drugs have been shown to generate liquid membranes in series with a supporting membrane (Sartorius celluose acetate microfiltration membrane). Transport of dextrose and ions, such as NH₄⁺, Mg²⁺, Ca²⁺, K⁺ and PO₄³⁻ has been studied in the presence of liquid membranes generated by these drugs. The data obtained on the modification in the permeability of dextrose and ions in the presence of liquid membrane indicate the significance of liquid membranes in passive transport. <br/> <br/>Page(s): 48-52 http://nopr.niscair.res.in/handle/123456789/3633 Title: Evidence of free radical participation in N-glycolylneuraminic acid generation in liver of chicken treated with gallotannic acid <br/> <br/>Authors: Mwangi, Danny W; Bansal, Devi D <br/> <br/>Abstract: The occurrence of N-glycolylneuraminic acid (Neu5Gc) in cancerous tissue and inflammatory diseases, conditions associated with increased oxidative stress suggests the participation of reactive oxygen radicals in Neu5Gc generation, where an oxygen atom is transferred. To study this possibility, we treated two groups of domesticated birds and rabbits with different dosages of gallotannic acid (GTA), a compound known to cause generation of reactive oxygen species (ROS). The antioxidant status and leukocyte capacity, as well as amount and form of sialic acids were assessed in plasma and liver. Results showed that while lipid peroxides were increased, white blood cell (WBC) count was decreased significantly in all treated groups. The increased sialic acids and low protein contents were observed in plasma, possibly as a result of decreased sialic acid cycling crucial for formation of new glycoconjugates in tissues, caused by decreased protein synthesis due to microsomal degranulation. The activities of antioxidant enzymes were also decreased in treated groups, implying increased oxidative stress. The presence of Neu5Gc and apparent absence of Neu5Ac hydroxylase activity in liver of chicken treated with GTA indicate that free radicals might be involved in the non-enzymatic hydroxylation of N-acetylneuraminic acid (Neu5Ac) to Neu5Gc in liver, which normally does not express this sialic acid. <br/> <br/>Page(s): 20-28