ABSTRACT
In West Bengal, India arsenic in ground water has been found to be above the maximum permissible limit in seven districts covering an area of 37,493km2. In the present study, evaluation of the micronuclei (MN) formation in oral mucosa cells, urothelial cells and peripheral blood lymphocytes was carried out in the symptomatic individuals exposed to arsenic through drinking water. Forty five individuals with cutaneous signs of arsenicism from four affected districts (368.11 microg/l of As in drinking water) were considered as the exposed group and 21 healthy individuals with no symptoms of arsenic poisoning and residing in two unaffected districts (5.49 microg/l of As) were considered as controls. The exposed and control groups had similar age distribution and socioeconomic status. Standardised questionnaires were utilised and medical examination was conducted to ascertain exposure history, sociodemographic characteristics, diet, health, medication, addiction and chief symptoms in the study participants. Arsenic exposure was confirmed by measuring the arsenic content in the drinking water, nails, hair and urine samples from the volunteers. Arsenic contents in the urine, nail and hair in the exposed group were 24.45 microg/l, 12.58 and 6.97 microg/g, respectively which were significantly high in comparison to corresponding control group values of 4.88 microg/l, 0.51 and 0.34 microg/g, respectively. Exposed individuals showed a statistically significant increase in the frequency of MN in oral mucosa, urothelial cells and lymphocytes (5.15, 5.74 and 6.39/1000 cells, respectively) when compared with the controls (0.77, 0.56 and 0.53/1000 cells, respectively). Thus, the above results indicate that the symptomatic individuals exposed to arsenic through drinking water in this region have significant cytogenetic damage.
Subject(s)
Arsenic/adverse effects , Environmental Exposure/adverse effects , Epithelial Cells/pathology , Micronuclei, Chromosome-Defective/pathology , Water Pollutants, Chemical/adverse effects , Adolescent , Adult , Arsenic/metabolism , Arsenic/urine , Cell Nucleus/drug effects , Epithelial Cells/drug effects , Female , Humans , India/epidemiology , Lymphocytes/drug effects , Lymphocytes/metabolism , Male , Micronucleus Tests , Middle Aged , Mouth Mucosa/drug effects , Mouth Mucosa/metabolism , Urinary Bladder/drug effects , Urinary Bladder/metabolism , Water Pollutants, Chemical/analysisABSTRACT
In vitro polymerization of purified goat brain tubulin is stimulated at low Ni2+ concentration, whereas at high nickel concentration (greater than 1 . 10(-4)) polymerization is inhibited. Ni2+, over the concentration range of 1 . 10(-4)-1 . 10(-3) M, enhances the rate of colchicine binding to tubulin, although in its presence the colchicine binding site of tubulin is degraded at a much faster rate at 37 degrees C. Finally, incubation of tubulin with Ni2+ at 37 degrees C gradually alters the native conformation of the protein, as revealed by the quenching of intrinsic tryptophan fluorescence.
