Prevalence of CYP1A1 and GST polymorphisms in the population of northeastern India and susceptibility of oral cancer.

Individual cancer susceptibility is the result of several host factors, including differences in lifestyle habits and genetic susceptibility. There is a correlation between CYP1A1 polymorphism (MspI) and oral cancer susceptibility. Individuals carrying the deletions of GSTM1 and GSTT1 are at high risk of developing oral cancers.

Anemia and hemoglobinopathies in tribal population of Eastern and North-eastern India.

It is estimated that out of approximately 31.4 million people living in North-eastern India, about 8.1 million are tribal people of the hills and plains.

Alpha-thalassemia among tribal populations of Eastern India.

Five hundred and thirteen unrelated subjects belonging to various tribes of West Bengal, Arunachal Pradesh and Assam in Eastern India, were screened for the presence of alpha-thalassemia (thal) gene deletion(s) as a possible cause of unexplained anemia (Hb < 11 g/dL and/or MCH <28 pg, MCV < 78 fL). As reported earlier, beta-globin gene mutant alleles were found with a frequency of up to 20% in some tribes. In the present study, alpha-globin gene deletion alleles were found in 18% of subjects from West Bengal, 3.

Induction of micronuclei by zinc in human leukocytes: a study using cytokinesis-block micronucleus assay.

In the present study, we report the results of the capability of zinc chloride for the induction of micronuclei in cultured human leukocytes using cytokinesis-block micronucleus assay. Two concentrations of zinc chloride (1.5 x 10(-4) M and 3.

Spectrum of beta-thalassemia mutations and their association with allelic sequence polymorphisms at the beta-globin gene cluster in an Eastern Indian population.

In this report, the spectrum of beta-thalassemia mutations and genotype-to-phenotype correlations were defined in large number of patients (beta-thalassemia carriers and major) with varying disease severity in an Eastern Indian population mainly from the state of West Bengal. The five most common beta-thalassemia mutations were detected, which included IVS1-5 (G-->C), codon 15 (G-->A), codon 26 (G-->A), codon 30 (G-->C), and codon 41/42 (-TCTT). These accounted for 85% in 80 beta-thalassemic alleles deciphered from 56 patients, including beta-thalassemia major and carriers, and 15% of alleles remained uncharacterized in these patients.

Study of the single nucleotide polymorphism (SNP) at the palindromic sequence of hypersensitive site (HS)4 of the human beta-globin locus control region (LCR) in Indian population.

LCR, a genetic regulatory element, was examined in beta-thalassemia patients who do not show any mutation in the beta-globin genes. We sequenced LCR-HS2, HS3, and HS4 in samples from 16 such patients from the Indian population and found only one SNP A-G in the inverted repeat in HS4. A significant association was observed between the G allele and occurrence of beta-thalassemia by Fisher's exact test.

A review on the origin and spread of deleterious mutants of the beta-globin gene in Indian populations.

Deleterious mutations of the human beta-globin gene are responsible for beta-thalassaemia and other haemoglobinopathies, which are the most common genetic diseases in Indian populations. A highly heterogeneous distribution of those mutations is observed in India and certain mutations are restricted to some extent to particular groups only. The reasons behind the geographical clustering and origin of the mutations in India is a highly debated issue and the evidence is conflicting.

Molecular characterization of hereditary persistence of foetal haemoglobin mutation by restriction fragment length polymorphism mapping.

Characterization of hereditary persistence of foetal haemoglobin (HPFH) mutation in a family from West Bengal, India, was carried out by analysing the structure of the 5'-Ggamma-Agamma-psibeta-delta-beta-3' globin gene region by using the restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) technique. The HPFH in this family was due to a deletion in the beta-globin gene cluster spanning at least from the Hin cII/5' psibeta to the Hin fI/3' beta RFLP site. This work indicates the importance of RFLP-PCR technique in characterization of the HPFH mutation.

Interaction of different hemoglobinopathies in Eastern India with a view to establish genotype-phenotype correlation.

Analysis of the molecular basis of hemoglobinopathies provides an opportunity to define genotype-phenotype variations as well as establish the origin of mutation. The present study deals with a large cohort of 1,661 cases referred to the counseling unit and 889 individuals from random screening of the population of Tripura. Characterization of mutation in 291 cases (582 alleles) was performed by the PCR-ARMS method using genomic DNA.

Comparison of chromosome damage induced by three zinc compounds using human leukocyte culture.

The degree of chromosome damage induced by three compounds of zinc (zinc chloride, zinc sulfate, zinc acetate) was compared in human leucocytes in vitro. Three concentrations of each salt, 3.0 x 10(-5)M, 3.

Chromosome damage induced by selenium salts in human peripheral lymphocytes.

Two inorganic salts of selenium, sodium selenite (Na(2)SeO(3)) and sodium selenate (Na(2)SeO(4)), were screened for damage to chromosome and cell division following exposure to human lymphocyte cultures. In vitro exposure of human peripheral blood lymphocytes to high concentration of two inorganic salts of selenium-sodium selenite (2.9 x 10(-5) M) and sodium selenate (2.

Dietary protection by iron against clastogenic effects of short-term exposure to arsenic in mice in vivo.

Iron, as freshly prepared aqueous solution of ferrous sulfate, was administered by gavage to laboratory bred Swiss albino mice. The concentration used was 152 mg/kg body weight (1/10 of the LD(50)). While screening for protection against arsenic, in one set of experiment exposure to iron was followed after 2 hr by gavaging with 2.

Clastogenic effects of zinc chloride on human peripheral blood leucocytes in vitro.

The clastogenic effects of three different concentrations of zinc chloride on human peripheral blood leucocytes were studied in vitro. The highest concentration (1.5 x 10(-3) M) was lethal after 48 and 72 h of culture and no blast cells were formed.

Comparison of clastogenic effects of inorganic selenium salts in mice in vivo as related to concentrations and duration of exposure.

Inorganic selenium compounds in the diet have been known to protect against cancer in laboratory animals, but were harmful in high concentrations. In the present work, the relative effects of two salts, sodium selenite and sodium selenate, administered to mice in vivo, in different concentrations and durations of exposure, were compared. Aqueous solutions of each salt (7, 14, 21 and 28 mg Kg-1 bw) were fed by gavaging to mice matched in age and sex.

Complex voltage-dependent behavior of single unliganded calcium-sensitive potassium channels.

study and characterization of unliganded openings is of central significance for the elucidation of gating mechanisms for allosteric ligand-gated ion channels. Unliganded openings have been reported for many channel types, but their low open probability can make it difficult to study their kinetics in detail. Because the large conductance calcium-activated potassium channel mSlo is sensitive to both intracellular calcium and to membrane potential, we have been able to obtain stable unliganded single-channel recordings of mSlo with relatively high opening probability.

Protection against cytotoxic effects of arsenic by dietary supplementation with crude extract of Emblica officinalis fruit.

Dietary administration of a crude aqueous extract of Emblica officinalis Gaertn. fruit reduced significantly the cytotoxic effects of sodium arsenite administered orally. The crude extract (685 mg/kg bw) was given daily by gavaging to age and sex matched laboratory bread Swiss albino mice for 7 and 14 days, followed by a single dose of sodium arsenite (2.

Prevention of cytotoxic effects of arsenic by short-term dietary supplementation with selenium in mice in vivo.

Interaction between selenium and arsenic has been used to protect against the genotoxic effects of sodium arsenite through dietary intervention by an equivalent amount (1/10 LD50) of sodium selenite. The two salts were administered by gavaging to laboratory bred Swiss albino mice sequentially and in combination. Cytogenetic endpoints, including chromosomal aberrations (CA) and damaged cells (DC) were recorded 24 h after exposure from chromosome spreads in bone marrow cells.

Inhibition of clastogenic effects of arsenic through continued oral administration of garlic extract in mice in vivo.

Crude aqueous extract of garlic bulbs (Allium sativum L. single clove variety) was administered by gavage to mice of both sexes daily for up to 30 and 60 days, in doses corresponding to 6 g for a 60 kg human body. Sodium arsenite (at 1/50 of LD50 dose) was injected subcutaneously to mice on every 7th day of the experiment.

The occurrence of beta-thalassemia mutation and its interaction with hemoglobin E in the eastern India.

The distribution of variant hemoglobin in India has been related to various ethnic groups among other factors. beta-Thalassemia is the most frequent monogenic disorder in the country. Analysis of hemoglobin of 435 cases from Eastern India was performed by electrophoresis and by other quantitative methods.

Selenium salts and chromosome damage.

Sodium selenite and sodium selenate, fed by gavaging to age-matched male Swiss albino mice and observed after 24 h following a colchicine-fixative-air drying-Giemsa schedule, were found to induce chromosome breaks and spindle disturbances in bone marrow cells. The four concentrations used were fractions of LD50 and the effects were directly proportionate to the concentration of the chemical. Sodium selenite induced a slightly higher frequency of chromosomal aberrations than sodium selenate.

Dietary chemoprevention of clastogenic effects of 3,4-benzo(a)pyrene by Emblica officinalis Gaertn. fruit extract.

Dietary supplementation with extract of fruit of Emblica officinalis Gaertn. (a rich source of vitamin C) to mice in vivo significantly reduced the cytotoxic effects of a known carcinogen, 3,4-benzo(a)pyrene. Age-matched Swiss albino mice were fed by gavaging the fruit extract daily for 28 days.