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Banudevi S, Elumalai P, Arunkumar R, Senthilkumar K, Gunadharini DN, Sharmila G, Arunakaran J. Chemopreventive effects of zinc on prostate carcinogenesis induced by N-methyl-N-nitrosourea and testosterone in adult male Sprague-Dawley rats. J Cancer Res Clin Oncol 2010; 137:677-86. [DOI: 10.1007/s00432-010-0926-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2010] [Accepted: 05/26/2010] [Indexed: 11/29/2022]
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Senthilkumar K, Chidanand M, Nijalingappa P, Shivhare M. Design, Development, and Validation of a Vehicle-mounted Hydraulically-leveled Platform. DEFENCE SCI J 2010. [DOI: 10.14429/dsj.60.336] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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78
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Senthilkumar K, Tokunaga M, Okamoto H, Senthilkumar O, Lin J, Urban B, Neogi A, Fujita Y. Multiphonon scattering and non-radiative decay in ZnO nanoparticles. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/pssc.200983203] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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79
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Santhanamoorthi N, Senthilkumar K, Kolandaivel P. Absorption and emission properties of phenylene ethynylene oligomers: effect of substitution and π-conjugation length. Mol Phys 2009. [DOI: 10.1080/00268970902997858] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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80
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Santhanamoorthi N, Kolandaivel P, Senthilkumar K. Effect of conformational degrees of freedom on the charge transfer in model tripeptide. J Mol Graph Model 2009; 27:784-91. [DOI: 10.1016/j.jmgm.2008.11.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2008] [Revised: 11/18/2008] [Accepted: 11/21/2008] [Indexed: 10/21/2022]
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81
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Palanivelu C, Rangarajan M, Parthasarathi R, Madankumar MV, Senthilkumar K. Laparoscopic repair of suprapubic incisional hernias: suturing and intraperitoneal composite mesh onlay. A retrospective study. Hernia 2008; 12:251-6. [PMID: 18253807 DOI: 10.1007/s10029-008-0337-5] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2007] [Accepted: 01/09/2008] [Indexed: 11/26/2022]
Abstract
BACKGROUND Suprapubic hernias are those defects located 4 cm from the pubic symphysis. Our aim is to highlight the laparoscopic repair of suprapubic incisional hernias. PATIENTS AND METHODS We retrospectively reviewed 17 patients with suprapubic incisional hernias from 1999 to 2007. A modified technique of laparoscopic intraperitoneal composite mesh onlay was performed for these patients. RESULTS There were 12 females and 5 males with a mean age of 55.9 years and a mean BMI of 30 kg/m(2). The mean hernia size was 87.5 cm(2), with an average mesh size of 234 cm(2). Mean follow-up was 9 months. Complications were seen in five patients, with an overall recurrence rate of 5.8%. DISCUSSION Suprapubic hernias are difficult to manage because of the complexity of dissection and their anatomic proximity to bony, vascular and nerve structures. The lower end of the mesh should be fixed to the Cooper's ligament and the pubic bone. Laparoscopic repair of these uncommon hernias is safe, effective and provides all the benefits of minimally invasive surgery.
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Sridevi N, Venkataraman P, Senthilkumar K, Krishnamoorthy G, Arunakaran J. Oxidative stress modulates membrane bound ATPases in brain regions of PCB (Aroclor 1254) exposed rats: Protective role of α-tocopherol. Biomed Pharmacother 2007; 61:435-40. [PMID: 17459649 DOI: 10.1016/j.biopha.2007.03.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2007] [Accepted: 03/08/2007] [Indexed: 01/10/2023] Open
Abstract
Polychlorinated biphenyls (PCBs) are a class of widely dispersed and environmentally persistent organic compounds. PCBs exhibit a wide range of toxicological effects including neurotoxicity. Vitamin E (alpha-tocopherol) is an important lipid soluble antioxidant placed in a special region of membranes. Large amounts of energy are required to maintain the signaling activities of the cells in the central nervous system (CNS). Membrane proteins that control ion gradients across organellar and plasma membranes appear to be particularly susceptible to oxidation-induced changes. The aim of this study was to determine the protective role of vitamin E on Aroclor 1254 induced modulation in membrane bound ATPases in brain regions of rats. One group of rats received corn oil as vehicle for 30days as control. The other group of rats were administered Aroclor 1254 at a dose of 2mgkg(-1) bwday(-1) intraperitoneally for 30days. One group of rats received vitamin E (50mgkg(-1) bwday(-1)) orally simultaneously with Aroclor 1254 for 30days. After 30days, the animals were euthanized and the brain was dissected to hypothalamus and hippocampus to determine the following parameters. Hydrogen peroxide (H2O2), Lipid peroxidation (LPO) and the activities of Na+K+-ATPase, Ca2+-ATPase and Mg2+-ATPase were determined. Reduced glutathione (GSH) level was also determined. Activities of all the enzymes were decreased while an increase in H2O2 and LPO were observed in selected brain regions of PCB treated animals. Simultaneous vitamin E treatment in PCB exposed animals restored all the parameters significantly. These results suggest that oxidative stress is involved in the inhibitory effect of PCB (Aroclor 1254) on membrane bound ATPases in selected brain regions. alpha-tocopherol acts against PCB induced neurotoxicity by decreasing oxidative stress.
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Palanivelu C, Rangarajan M, John SJ, Madankumar MV, Senthilkumar K. Laparoscopic transperitoneal repair of lumbar incisional hernias: a combined suture and 'double-mesh' technique. Hernia 2007; 12:27-31. [PMID: 17668145 DOI: 10.1007/s10029-007-0270-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2006] [Accepted: 07/10/2007] [Indexed: 10/23/2022]
Abstract
BACKGROUND Lumbar hernias that occur after surgery are called lumbar incisional hernias. Recently, laparoscopic repair of these hernias has been reported with excellent outcomes. This is a retrospective study of our series of patients with lumbar incisional hernias. PATIENTS AND METHODS We managed 11 patients with lumbar incisional hernias from 1996-2006. All the patients had undergone either nephrectomy or pyeloplasty in the past. Laparoscopic suturing of the defect and reinforcement with mesh were successfully performed for all the patients. RESULTS There were more males than females, the age range was 42-65 years, and mean operating time was 120 min; discharge was at 1-2 postoperative days. There was no recurrence or mortality. Three cases had seroma, out of which two required aspiration after 60 days. DISCUSSION Laparoscopic repair provides all the benefits of minimally invasive surgery, and the principles involved in repair of ventral hernias are applied in lumbar incisional hernias as well. Our technique involved suturing of the defect before placing a mesh over the defect. We theorize that approximating the ends of the muscles restores normal anatomy and results in functional improvement. For the larger hernias, we used two meshes to cover the defect--polypropylene and Parietex, sizes being 15 x 15 cm. CONCLUSION Laparoscopic repair with prosthetic reinforcement is feasible and effective in the treatment of lumbar incisional hernias. Also, suturing of the defect may provide additional benefits.
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Santhanamoorthi N, Kolandaivel P, Senthilkumar K. Theoretical investigation on intramolecular electron transfer in polypeptides. Chem Phys Lett 2007. [DOI: 10.1016/j.cplett.2007.04.050] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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85
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Kanagaraj P, Vijayababu MR, Ilangovan R, Senthilkumar K, Venkataraman P, Aruldhas MM, Arunakaran J. Effect of 17beta-estradiol on apoptosis, IGF system components and gelatinases A and B in prostate cancer cells (PC-3). Clin Chim Acta 2006; 377:70-8. [PMID: 17083925 DOI: 10.1016/j.cca.2006.07.030] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2005] [Revised: 07/26/2006] [Accepted: 07/29/2006] [Indexed: 11/16/2022]
Abstract
BACKGROUND Previous studies have indicated that estrogen administration in the advanced stage of prostate cancer provide some benefits to the patients. Estrogen action was thought to be mediated via the blockade of the pituitary-testicular axis that effectively lowered the circulating levels of androgen and, thus, results in tumor regression; however, the effect of estrogens on prostate epithelial cells is still unclear. We investigated the effects of estradiol on insulin-like growth factor type I receptor (IGF-IR), IGF-binding protein 3 (IGFBP-3), IGFBP-4, and matrix metalloproteinase 2 (MMP-2) and MMP-9 in androgen-independent prostate cancer cells (PC-3). METHODS The cells were treated with different concentrations of estradiol (1, 10 and 100 nmol/l) for different time periods (24, 48, 72 and 96 h). Cell proliferation was assessed using MTT assay, and IGFBP-3 and IGFBP-4 were assessed using immunoradiometric and enzyme immunoassays, respectively. MMP-2, MMP-9 and IGF-IR expression levels were analyzed using western-blot analysis, and MMP-2 and MMP-9 activities were analyzed using gelatin zymography. Apoptosis was confirmed by Annexin V-FITC and acridine orange and ethidium bromide staining methods. DNA fragmentation studies were also performed. RESULTS Cell proliferation assay revealed that 10 and 100 nmol/l estradiol concentrations inhibit the proliferation of PC-3 cells when incubated for 48-96 h. The secretory levels of IGFBP-3 and IGFBP-4 were increased significantly. The western-blot results showed that estradiol is capable of decreasing the expression of MMP-2 and MMP-9 significantly. Gelatin zymography showed that activities of MMP-2 and MMP-9 are decreased in estradiol-treated cells. Estradiol-induced apoptosis was studied using annexin V-binding and propidium iodide influx. Estradiol also induced nuclear fragmentation in higher doses (100 nmol/l) in PC-3 cells. CONCLUSION Inhibition of MMPs in cancer cells and increased levels of IGFBP-3 and IGFBP-4 associated with apoptosis may be one of the targets for anticancer function of estradiol. Estradiol inhibits the proliferation of prostate cancer cells by inducing apoptosis.
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Santhanamoorthi N, Kolandaivel P, Senthilkumar K. Charge Transfer in Polypeptides: Effect of Secondary Structures on Charge-Transfer Integral and Site Energies. J Phys Chem A 2006; 110:11551-6. [PMID: 17020269 DOI: 10.1021/jp063069n] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have theoretically studied the charge transfer in glycine polypeptide using quantum mechanical models based on a tight-binding Hamiltonian approach. The charge-transfer integrals and site energies involved in the transport of positive charge through the peptide bond in glycine polypeptide have been calculated. The charge-transfer integrals and site energies have been calculated directly from the matrix elements of the Kohn-Sham Hamiltonian defined in terms of the molecular orbitals of the individual fragments of the glycine polypeptide. In addition to this, we have calculated the rate of charge transfer between a neighboring amino acid subgroup through the Marcus rate equation. These calculations have been performed for the different secondary structures of the glycine model peptide such as linear, alpha-helix, 3(10)-helix, and antiparallel beta-sheet by varying the dihedral angles omega, varphi, and psi along the Calpha-carbon of amino acid subgroup. Present theoretical results confirm that the charge transfer through the peptide bond is strongly affected by the conformations of the oligopeptide.
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Takasuga T, Senthilkumar K, Tsuji H, Nagayama J. Impact of fermented brown rice with Aspergillus oryzae intake and concentrations of organochlorine pesticides in blood of humans from Japan. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2006; 76:752-9. [PMID: 16786444 DOI: 10.1007/s00128-006-0984-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2005] [Accepted: 03/09/2006] [Indexed: 05/10/2023]
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Senthilkumar K, Raman MS, Kolandaivel P. Effect of substitution of electron-donating and -withdrawing groups on the stability of flavin–diaminepyridine complexes—a density functional theory study. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.theochem.2005.10.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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89
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Senthilkumar K, Arunkumar A, Sridevi N, Vijayababu MR, Kanagaraj P, Venkataraman P, Aruldhas MM, Srinivasan N, Arunakaran J. Chemoprevention of MNU and Testosterone induced prostate carcinogenesis by Calcitriol (vitamin D3) in adult male albino Wistar rats. ACTA ACUST UNITED AC 2006. [DOI: 10.4993/acrt.14.12] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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90
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Senthilkumar K, Thirumurugan R, Khan PN. Chemical immobilization of Grant's Zebra Equus burchelli boehmi for examination and treatment of lameness. ACTA ACUST UNITED AC 2005. [DOI: 10.11609/jott.zpj.1330a.1914] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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91
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Koh CH, Khim JS, Kannan K, Villeneuve DL, Senthilkumar K, Giesy JP. Polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) and 2,3,7,8-TCDD equivalents (TEQs) in sediment from the Hyeongsan River, Korea. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2004; 132:489-501. [PMID: 15325465 DOI: 10.1016/j.envpol.2004.05.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2003] [Accepted: 05/03/2004] [Indexed: 05/22/2023]
Abstract
Sediment, pore water and water samples from the Hyeongsan River, Korea were analyzed for several classes of halogenated aromatic hydrocarbons (HAHs) and their dioxin-like activities were evaluated using the in vitro H4IIE-luc bioassay. Polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) were detected in sediments from all six sampling locations with mean concentrations of 2.8 x 10(2) pg/g, 190 pg/g, and 61.4 ng/g, dw, respectively. Polycyclic aromatic hydrocarbons (PAHs) were predominated by 4-6 ring compounds with concentrations in the range of 5.30-7680 ng/g, dw. Chemical profiles of target analytes in sediment and water samples revealed that there was a gradient of concentrations along the river from upstream to downstream, which suggested that the primary source was a wastewater reservoir adjacent to a sewage treatment plant (STP). TEQs derived by summing the product of concentrations of individual congeners by their respective relative potencies (REPs or TEFs) ranged from 4.3 x 10(-1) to 1.1 x 10(3) pg/g, dw. Raw Soxhlet extracts from all six sampling locations induced significant dioxin-like responses in the H4IIE-luc bioassay. TCDD-EQs derived from H4IIE bioassay ranged from 7 x 10(-3) to 1.5 x 10(3) pg/g, dw, which were significantly correlated with TEQs (r2 = 0.994, p < 0.05). Among the three Florisil fractions tested, PCDD/Fs in fraction (F2) induced the greatest magnitude of response (range: 24-83%-TCDD-max.) in the H4IIE-luc assay. Comparison of the TEQ and TCDD-EQ suggested little non-additive interaction between fractions and AhR-active and inactive compounds. Concentrations of individual congeners as well as TEQs and TCDD-EQs suggest inputs from the industrial center waste stream in the Hyeongsan River.
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Senthilkumar K, Grozema FC, Guerra CF, Bickelhaupt FM, Siebbeles LDA. Mapping the sites for selective oxidation of guanines in DNA. J Am Chem Soc 2004; 125:13658-9. [PMID: 14599193 DOI: 10.1021/ja037027d] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The effective energy of a positive charge when it is localized at a specific guanine nucleobase in DNA was calculated using density functional theory. The results demonstrate that the efficiency of a guanine to act as a hole-trap in DNA strongly depends on the nature of the flanking nucleobases. The presence of a pyrimidine base at the 3' position adjacent to a guanine significantly increases the localization energy of the positive charge. The calculated distributions of a positive charge in sequences of two or three adjacent guanines, flanked by other nucleobases, provide an explanation for experimental literature data on the site-selective oxidation of DNA.
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Selvi P, Ramasami M, Samuel MHP, Sripriya R, Senthilkumar K, Adaikkalam P, Srinivasan GN. Gallium recovery from Bayer's liquor using hydroxamic acid resin. J Appl Polym Sci 2004. [DOI: 10.1002/app.20047] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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94
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Senthilkumar K, Grozema FC, Bickelhaupt FM, Siebbeles LDA. Charge transport in columnar stacked triphenylenes: Effects of conformational fluctuations on charge transfer integrals and site energies. J Chem Phys 2003. [DOI: 10.1063/1.1615476] [Citation(s) in RCA: 358] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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95
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Senthilkumar K, Kolandaivel P. Structure, conformation and NMR studies on 1,2-dioxane and halogen substituted 1,2-dioxane molecules. Comput Biol Chem 2003; 27:173-83. [PMID: 12927094 DOI: 10.1016/s0097-8485(02)00019-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Molecular structure and conformational stability of chair and twist conformers of 1,2-dioxane and halogen substituted compounds of the 1,2-dioxane have been studied using ab initio and density functional theory (DFT) methods. The molecular geometries of 1,2-dioxane, 3,6-difluoro, 3,6-dichloro, 3,3,6,6-tetrafluoro and 3,3,6,6-tetrachloro 1,2-dioxane compounds were optimized at HF, MP2, B3LYP and B3PW91 levels of theory by implementing 6-31G* basis set. To study the effect of polar medium, self-consistent reaction field theory is used to optimize the conformers at B3LYP/6-31G* level of theory. The geometrical parameters of chair and twist conformers have been discussed in the light of interaction between lone pair electrons present in the oxygen and substituted halogen atoms. The relative stability of the conformers have been studied using relative energy, maximum hardness principle and thermodynamical quantities. The 13C-NMR chemical shift study for carbon atoms in the title compounds are calculated and the results have been discussed.
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96
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Senthilkumar K, Kolandaivel P. Quantum chemical studies on tautomerism of barbituric acid in gas phase and in solution. J Comput Aided Mol Des 2002; 16:263-72. [PMID: 12400856 DOI: 10.1023/a:1020273219651] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Ab inito and density functional theory (DFT) methods were used to study the tautomers of barbituric acid in the gas phase and in a polar medium. In the gas phase, the tautomers were optimized at the HF/6-31G*, MP2/6-31G* and B3LYP/6-31G*, B3PW91/6-31G* levels of theory. The self-consistent reaction field theory (SCRF) at the HF/6-31G* level of theory has been used to optimize the tautomers in a polar medium. The relative stability of the tautomers was compared in the gaseous and polar mediums. The ability of maximum hardness principle to predict the stable tautomer has been studied. The 13C-NMR chemical shift for carbon atoms in the tautomers was calculated and the results are discussed.
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Senthilkumar K, Kolandaivel P. Post Hartree-Fock and density functional theory studies on structure and conformational stability of nitrosoethylene and substituted compounds of nitrosoethylene. COMPUTERS & CHEMISTRY 2002; 26:207-21. [PMID: 11868910 DOI: 10.1016/s0097-8485(01)00109-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Post Hartree-Fock and density functional theory (DFT) methods were used to study the different conformers of nitrosoethylene H-CH=CH-NO, and substituted compounds of the nitrosoethylene R-CH=CH-NO (R = Cl, NH2, N(CH3)2, OH, OCH3). The molecules were optimized at MP2/6-31G* level of theory of ab initio and B3LYP/6-31G* and B3PW91/6-31G* levels of theory of DFT. Special emphasis has been given to the effect of substitution of pi-electron donor groups NH2, N(CH3)2, OH, and OCH3, which play a major role in modifying the geometrical parameters of -N=O group by the electronic transmission effects through the central group -CH=CH-. The ability of DFT methods to predict the bond length adjacent to the atoms having lone pair electrons has been discussed. The conformational stabilities have been studied using the relative energies and DFT parameters such as chemical hardness and chemical potential. The role of intra-molecular hydrogen bond on the equilibrium structure has been discussed. The vibrational spectra for the different conformers of the nitrosoethylene and substituted compounds have been generated using the MP2/6-31G* level of theory.
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Senthilkumar K, Iseki N, Hayama S, Nakanishi J, Masunaga S. Polychlorinated dibenzo-p-dioxins, dibenzofurans, and dioxin-like polychlorinated biphenyls in livers of birds from Japan. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2002; 42:244-255. [PMID: 11815817 DOI: 10.1007/s00244-001-0030-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2001] [Accepted: 08/05/2001] [Indexed: 05/23/2023]
Abstract
Concentrations of 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and non- and mono-ortho-chlorine-substituted polychlorinated biphenyls (dioxin-like PCBs) were measured in livers of 17 species of birds collected from Japan. Birds were grouped according to their feeding habits as granivores, piscivores, omnivores, and predators for discussions. Livers of granivores contained relatively low concentrations of PCDD/DFs (80-660 pg/g) followed in increasing order by omnivores (2,300-8,000 pg/g), piscivores (61-12,000 pg/g) and predators (480-490,000 pg/g on a fat weight basis). Especially, one species of predatory bird (mountain hawk eagle) contained elevated concentrations of PCDDs, PCDFs, and dioxin-like PCBs, and the measured concentration is one of the highest reported to date. Homolog and congener patterns of PCDDs and PCDFs varied among species; hence, the results suggested that feeding habits, specific elimination, and metabolism influence contamination pattern. Concentrations of dioxin-like PCBs were in the order of granivores (32-83 ng/g) < predators [excluding mountain hawk eagle] (32-2,500 ng/g) < piscivore (61-12,000 ng/g) < omnivores (1,800-67,000 ng/g on a fat weight basis). Mountain hawk eagle contained the highest concentration of dioxin-like PCBs (55,000 ng/g fat weight). 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) toxic equivalents (TEQs) ranged from 53-450,000 pg/g fat weight. 23478-PeCDF, 2378-TCDD/TCDF, and PCB congeners IUPAC 126 and 77 were major contributors to TEQs in birds. To our knowledge, this is the first study of PCDD/DFs and dioxin-like PCBs in livers of several species of Japanese birds.
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Senthilkumar K, Kannan K, Subramanian A, Tanabe S. Accumulation of organochlorine pesticides and polychlorinated biphenyls in sediments, aquatic organisms, birds, bird eggs and bat collected from south India. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2001; 8:35-47. [PMID: 11360792 DOI: 10.1007/bf02987293] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
Concentrations of polychlorinated biphenyls (PCBs), DDT and its metabolites (DDTs), HCH isomers (HCHs), chlordane compounds (CHLs) and hexachlorobenzene (HCB) were determined in sediment, soil, whole body homogenates of resident and migratory birds and their prey items (including fish, green mussel, snail, earthworm, crabs, prawn, lizard and frogs), bird eggs and bats collected from southern India during 1995 and 1998. Accumulation pattern of organochlorines (OCs) in biota was, in general, in the order, HCHs > DDTs > PCBs > CHLs = HCB. Magnitude of OC concentrations increased in the order of sediments < green mussel < earthworm < from < lizard < fish < bird egg < bats < birds tissues. Biomagnification features of OCs were examined in resident and migrant birds to evaluate the exposure levels of these chemicals in wintering grounds of migrant birds. Accumulation of DDTs in migratory birds during wintering in India may be of concern due to the great biomagnification potential of DDTs. Eggs of some resident species contained noticeable concentrations of OCs. Concentrations of OCs in three species of bats analyzed in this study were lower than that found in passerine birds. In addition to OCs, butyltin compounds were also detected at low concentrations in bats.
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Kolandaivel P, Senthilkumar K. Ab initio and DFT studies on structure and stability of aliphatic aldoxime molecules. ACTA ACUST UNITED AC 2001. [DOI: 10.1016/s0166-1280(00)00571-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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