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Madurai, India

Senthilkumar K.P.,Shree M And N Virani Science College | Senthilkumar K.P.,Madura College Autonomous | Thirumurugan R.,Bharathidasan University
Molecular Biology Reports | Year: 2014

Tobacco use and environmental air pollution are the established etiological factors in head and neck cancer (HNC) progression. Nevertheless, not all the inhabitants with high usage of tobacco from the same polluted locality are suffering with HNC and this is due to the existence of factors like inter-individual genetic polymorphisms, life time exposure to tobacco and the rate of xenobiotic metabolism enzyme (XME) activity. The present study investigates the polymorphic genotypes of the most important XME, glutathione-S-transferase Mu 1 (GST M1) and Theta 1 (GST T1) as the risk modulator to HNC among tobacco-habituated inhabitants of Saurashtra in Gujarat, a region in western India. A population based case-control study was done in 252 HNC patients and 504 healthy controls. Blood samples were collected from the subjects and investigated for polymorphic genotypes of GST M1 and GST T1. Estimation of the odds of risks was done by logistic regressions. Among the subjects with high usage of tobacco, M1 not null-T1 null genotypes presence was found as risk reducing factor to HNC with 0.334 folds (95 % CI; 0.170-0.659). The presence of M1 null-T1 not null genotypes was found with susceptibility to HNC among the subjects with no habit of tobacco chewing, adjusted odds ratio (AOR) 3.170 (1.128-8.913) and no habit of smoking, AOR of 2.544 (1.094-5.963). The present study reveals the finding of significantly increased risk to HNC by interactions of GST M1 null-GST T1 not null polymorphic genotypes among the subjects with nil or less tobacco usage shed some light for the insights of biomarker application in early detection of HNC. © 2014 Springer Science+Business Media. Source

Malarvizhi M.,Madura College Autonomous | Subramanian G.,PSYE Engg College | Athappan P.R.,Madurai Kamaraj University
Materials Science Forum | Year: 2011

This paper documents the detailed investigation of the relationship between molecular structure and biological activity of few tetraaza macrocyclic metal (II) complexes equipped by the template condensation of o-bromoaniline, ethylenediamine and salbenz in 2:1:1 ratio with metal (II) salts (1mM). All these complexes are found to be stable in air and soluble in CN 3CN or DMSO, and are characterized through spectral (UV-Vis, IR, EPR) and electrochemical methods. A square planar geometry is proposed for Cu(II), Ni(II) and Co(II) complexes, while an octahedral geometry is suggested for Mn(II) and Fe(II). The IR spectra indicate that the NH groups of the amine exist as such even after complexation without deprotonation, and all the complexes show a strong band in 1580-1590 cm -1 region corresponding to .(C=N), due to coordinated azomethine group to the metal. The solution electronic spectra of these complexes show intense LMCT bands around 400 nm. Intense electronic absorption spectra as well as the four line pattern in EPR spectra with broad g. suggests that the copper(II) complexes have distorted square planar geometry. On titration with herring sperm DNA, CuN 4, CoN 4, NiN 4 and MnN 4 complexes exhibit an abrupt amend in their electronic spectrum and cyclic voltammogram. The intense intraligand π-π* transition in the region 350-420 nm is found to show hypochromicity on titration with DNA in all these complexes, due to their electrostatic interaction with DNA. All these complexes show one well-defined quasi-reversible redox couple with values ranging from .Ep 137 to 337 mV. Their spectral and electrochemical outcome designate that the square planar complexes Cu(II), Co(II) and Ni(II) interact much better than the axially coordinated octahedral complexes Mn(II) and Fe(II). The decrease found in the negative absorption peak, characteristic peak due to helicity of DNA, in circular dichroism studies reflects the perversion in the helical nature of B-DNA upon the addition of complex. The binding of plasmid DNA by these complexes has also been investigated by agarose gel electrophoresis, remarkably Ni(II) complex was found to cleave the DNA double helix. © 2012 Trans Tech Publications, Switzerland. Source

Malarvizhi M.,Madura College Autonomous | Athappan P.R.,Madurai Kamaraj University
Materials Science Forum | Year: 2011

A series of copper(II) complexes with positive reduction potential have been synthesized by an in situ fashion by the reaction of a Knoevenagel condensate, salicylidenebenzoylacetone (salbenz) with 4-X-anilines and copper(II) chloride. The electronic spectra of these complexes in acetonitrile show d-d bands around 540 nm with high molar extinction coefficient (e~1600-1800 cm -1) due to lowering of symmetry around metal center, and MLCT band around 400 nm. The EPR spectral features with four g⊥ lines having g⊥ >2.0 >g., and a broadening of g. component suggest a lowered site symmetry around Cu(II) monomer. The cyclic voltammetric studies of Cu(II) complexes in CH 3CN shows a positive reduction potential (Epc = 492-451 mV) with moderately high peak to peak separation (.Ep=126-163mV). All these results are comparable with the results of natural blue copper proteins even in the absence of Scoordination, and suggest that they can mimic the functional properties of blue copper proteins. These complexes on interaction with herring sperm DNA, the intense intraligand (IL) π-π* transition around 300 nm is found to be hypochromic with a slight red shift. The hypochromism and moderate binding constant are indicative of binding of the complexes with DNA with an affinity less than the classical intercalators, due to the possible substitution of the two chlorides with the DNA base pairs and relatively bulky structure of ligand molecule. Additional evidence of DNACu( II) complex interaction was obtained by CD studies. The experimental results reveal that these complexes may serve as a model for blue copper proteins and as a tool for probing the structure of DNA. © 2012 Trans Tech Publications, Switzerland. Source

Rajesh K.,Vellore Institute of Technology | Vijayakumar V.,Vellore Institute of Technology | Narasimhamurthy T.,Indian Institute of Science | Suresh J.,Madura College Autonomous | Tiekink E.R.T.,University of Malaya
Acta Crystallographica Section E: Structure Reports Online | Year: 2010

The 1,4-dihydro-pyridine ring in the title compound, C17H 19NO5, has a flattened-boat conformation, and the benzene ring is almost orthogonal to it [dihedral angle = 82.98 (12)°]. The hydr-oxy group is disordered over two positions in a 0.780 (4):0.220 (4) ratio. In the crystal, hydrogen-bonding inter-actions of the type Na - H⋯Oc and Oh - H⋯Oc (a = amine, c = carbonyl and h = hydr-oxy) link the mol-ecules into a three-dimensional network. Source

Loghambal S.,Madura College Autonomous | Rajendran L.,Madura College Autonomous
Russian Journal of Electrochemistry | Year: 2011

The analytical expression of the concentration of the species, in the electrochemical cell, with tubular electrode and optical fibres inserted into it, from its two ends is derived using the finite Hankel transformation. A series form of an analytical expression for current and absorbance responses of the spectroelec-trochemical cell has been derived. The analytical expressions of current and absorbance in terms of parameters K f, K b, ε A and ε B for chronoamperometry are given. Available numerical results are compared with our analytical results and are found to be in good agreement. © 2011 Pleiades Publishing, Ltd. Source

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