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Kumar MJM, Ponvijay KS, Nandhini R, Nagarajan RS, Jose J, Srinivas G, Nagarajan P, Venkatesan R, Kumar K, Singh S. A mouse model for luminal epithelial like ER positive subtype of human breast cancer. BMC Cancer 2007; 7:180. [PMID: 17880731 PMCID: PMC2094712 DOI: 10.1186/1471-2407-7-180] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2007] [Accepted: 09/20/2007] [Indexed: 11/10/2022] Open
Abstract
Background Generation of novel spontaneous ER positive mammary tumor animal model from heterozygous NIH nude mice. Methods Using brother-sister mating with pedigree expansion system, we derived a colony of heterozygous breeding females showing ER-Positive tumors around the age of 6 months. Complete blood picture, differential leukocyte count, and serum levels of Estrogen, Alanine amino transferase (SGPT), Aspartate amino transferase (SGOT), total protein and albumin were estimated. Aspiration biopsies and microbiology were carried out. Gross pathology of the tumors and their metastatic potential were assessed. The tumors were excised and further characterized using histopathology, cytology, electron microscopy (EM), molecular markers and Mouse mammary Tumor Virus – Long Terminal Repeats (MMTV LTR) specific RT-PCR. Results The tumors originated from 2ndor 5thor both the mammary glands and were multi-nodulated with variable central necrosis accompanied with an accumulation of inflammatory exudate. Significant increases in estrogen, SGPT, SGOT and neutrophils levels were noticed. Histopathologically, invasive nodular masses of pleomorphic tubular neoplastic epithelial cells invaded fibro-vascular stroma, adjacent dermis and subcutaneous tissue. Metastatic spread through hematogenous and regional lymph nodes, into liver, lungs, spleen, heart and dermal lymphatics was observed. EM picture revealed no viral particles and MMTV-negativity was confirmed through MMTV LTR-specific RT-PCR. High expression of ER α, moderate to high expression of proliferating cell nuclear antigen (PCNA), moderate expression of vimentin and Cytokeratin 19 (K19) and low expression of p53 were observed in tumor sections, when compared with that of the normal mammary gland. Conclusion Since 75% of human breast cancer were classified ER-positive and as our model mimics (in most of the characteristics, such as histopathology, metastasis, high estrogen levels) the ER-positive luminal epithelial-like human breast cancer, this model will be an attractive tool to understand the biology of estrogen-dependant breast cancer in women. To our knowledge, this is the first report of a spontaneous mammary model displaying regional lymph node involvement with both hematogenous and lymphatic spread to liver, lung, heart, spleen and lymph nodes.
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MESH Headings
- Animals
- BRCA1 Protein/metabolism
- Biomarkers, Tumor/metabolism
- Carcinoma, Ductal, Breast/metabolism
- Carcinoma, Ductal, Breast/pathology
- Carcinoma, Ductal, Breast/secondary
- Disease Models, Animal
- Estrogens/metabolism
- Female
- Heart Neoplasms/metabolism
- Heart Neoplasms/secondary
- Heterozygote
- Humans
- Immunohistochemistry
- Inbreeding
- Keratin-19/metabolism
- Liver Neoplasms/metabolism
- Liver Neoplasms/secondary
- Lung Neoplasms/metabolism
- Lung Neoplasms/secondary
- Lymphatic Metastasis
- Mammary Neoplasms, Experimental/metabolism
- Mammary Neoplasms, Experimental/pathology
- Mice
- Mice, Nude
- Proliferating Cell Nuclear Antigen/metabolism
- Receptors, Estrogen/metabolism
- Splenic Neoplasms/metabolism
- Splenic Neoplasms/secondary
- Tumor Suppressor Protein p53/metabolism
- Vimentin/metabolism
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Kumaraguru Vasagam K, Balasubramanian T, Venkatesan R. Apparent digestibility of differently processed grain legumes, cow pea and mung bean in black tiger shrimp, Penaeus monodon Fabricius and associated histological anomalies in hepatopancreas and midgut. Anim Feed Sci Technol 2007. [DOI: 10.1016/j.anifeedsci.2006.03.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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78
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Rupesh KR, Deepalatha S, Krishnaveni M, Venkatesan R, Jayachandran S. Synthesis, characterization and in vitro biological activity studies of Cu–M (M=Cu2+, Co2+, Ni2+, Mn2+, Zn2+) bimetallic complexes. Eur J Med Chem 2006; 41:1494-503. [PMID: 17011670 DOI: 10.1016/j.ejmech.2005.11.016] [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: 06/30/2005] [Revised: 10/25/2005] [Accepted: 11/14/2005] [Indexed: 10/24/2022]
Abstract
Six new bimetallic complexes of the type CuCu, CuCo, CuNi, CuZn and CuMn were prepared. The structures of these complexes and the ligand have been proposed on the basis of FAB mass, elemental analysis, UV-vis, IR, EPR and CV studies. All the complexes completely cleave pBS (SK-) DNA at a concentration of 10 microM; however, even at lower concentrations of 2 microM and 0.1 microM, the complexes (I and Ia) showed partial cleavage. The results of the fluorescence binding studies of the metal complexes with CT-DNA showed that the presence of aliphatic ligands added additional binding effects including electrostatic, hydrogen binding and vander Waals interactions. Complexes (I, Ia) showed 50% inhibition of COX-1 and COX-2 activities at as low a concentration as 12.5 microM, 13.5 microM, 14 microM and 14.5 microM. Inhibition assay of top I and top II by different complexes in mutant yeast strains (JN394, JN394 t(-1) and JN394 t(2-5)) with all the complexes showed significant inhibition of topoisomerase at 5 microM concentration. Complexes I and Ia exhibited good anti-microbial activities against all human pathogens tested except Klebsiella pneumoniae. The following studies showed that among the synthesized bimetallic complexes, complexes I and Ia seem to be promising candidates possessing DNA cleavage activities besides anti-microbial and anti-inflammatory properties to serve as chemical nucleases and chemotherapeutic agents.
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79
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Mahesh Kumar J, Reddy PL, Aparna V, Srinivas G, Nagarajan P, Venkatesan R, Sreekumar C, Sesikaran B. Strobilocercus fasciolaris infection with hepatic sarcoma and gastroenteropathy in a Wistar colony. Vet Parasitol 2006; 141:362-7. [PMID: 16842924 DOI: 10.1016/j.vetpar.2006.05.029] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2006] [Revised: 05/06/2006] [Accepted: 05/29/2006] [Indexed: 11/26/2022]
Abstract
Tapeworm cysts were identified in liver of Wistar rats and it induced fibrosarcoma in liver and gastroenteropathy in stomach and intestine. The tapeworm larva was confirmed as Strobilocercus fasciolaris by PCR linked mitochondrial DNA sequencing. Light microscopy, special staining (masson trichrome) and immunoflouresence supported the diagnosis of fibrosarcoma. Infiltration of plasma cells, macrophages and eosinophils were observed in the liver section. Gastric mucosal hyperplasia, dilation of gastric glands with secretion, intestinal mucosal cell hyperplasia, proliferation of duodenal submucosal glands were confirmed by light microscopy and supported by PAS, AB staining. The concomitant development of hepatic sarcoma and gastroenteropathy by larvae of Taenia taeniaeformis (S. fasciolaris) infection is very rare and is the first reported case in Wistar rats to our knowledge.
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80
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Venkatesan R, . KKV, . TB. Culture of Marine Microalgae in Shrimp Farm Discharge Water: A Sustainable Approach to Reduce the Cost Production and Recovery of Nutrients. ACTA ACUST UNITED AC 2006. [DOI: 10.3923/jfas.2006.262.269] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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81
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Deepalatha S, Sambasiva Rao P, Venkatesan R. Spectroscopic and electrochemical studies of hetero-bimetallic copper complexes with Schiff's base ligand. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2006; 64:823-9. [PMID: 16563852 DOI: 10.1016/j.saa.2005.08.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2005] [Revised: 08/09/2005] [Accepted: 08/16/2005] [Indexed: 05/08/2023]
Abstract
Using Schiff's base ligand, several Cu(II) based bimetallic complexes such as Cu-Cu, Cu-Co, Cu-Ni, Cu-Zn, Cu-Mn have been prepared in a stepwise procedure. The structures of these complexes and the ligand have been proposed on the basis of FAB mass, elemental analysis, UV-vis, IR, electron paramagnetic resonance (EPR) and CV studies. EPR parameters, obtained through complete simulation, suggest that the formation of bimetallic complexes forces the Cu(II) centre to increase the flexibility in comparison with the monometallic Cu(II) complex. However, the nature of the second metal ion in the bimetallic complex effects the distortion around the first metal ion. The reduction of the complexes from Cu(II) to Cu(I) involves a large geometrical change and is found to be irreversible. A large positive shift is seen in the cathodic process, which can be ascribed to increased distortion due to bimetallic coordination. These complexes have potential usage in DNA studies.
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Deepalatha S, Rao PS, Venkatesan R. Synthesis, physico-chemical and DNA interaction studies of homo- and hetero-trinuclear complexes. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2006; 64:178-87. [PMID: 16384732 DOI: 10.1016/j.saa.2005.07.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2005] [Revised: 06/30/2005] [Accepted: 07/01/2005] [Indexed: 05/05/2023]
Abstract
Synthesis and characterization of three new trinuclear metal complexes of type Cu3, Cu2Zn and Cu2Ni have been achieved by assembling simple mononuclear complexes, namely 2,2'-bipyridyl 3,4-dihydroxo benzaldehyde copper(II) complex and diethylenetriamine complexes of copper(II), nickel(II) and zinc(II) ions, through the reaction of coordinated ligands. The FAB mass spectra for the complexes show fragmentation pattern in accordance with the molecular formula. The frozen electron paramagnetic resonance (EPR) spectrum of tricopper complex shows two sets of parallel lines with approximately 2:1 ratio. The simulation has been carried out by considering dipolar interaction between the two types of copper ions present in the complex. The trimetallic complexes, Cu3, Cu2Ni and Cu2Zn show strong intercalation type of interaction with Calf thymus DNA in 0.02 mol L(-1) of phosphate buffer containing 60 mmol sodium chloride at pH 7.0 at room temperature. The binding constant is found to be in the order Cu3<Cu2Zn<Cu2Ni. The enhanced binding capability of Cu2Ni complex is attributed to the increased symmetry in the overall structure of the complex and the pronounced binding character of positively charged Ni(II) ions with the purines.
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Velavan K, Venkatesan R, Sambasiva Rao P. EPR of vanadyl impurity in zinc ammonium trihydrogen bis(orthophosphate) monohydrate single crystal. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2005; 62:153-6. [PMID: 16257707 DOI: 10.1016/j.saa.2004.12.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2004] [Accepted: 12/10/2004] [Indexed: 05/05/2023]
Abstract
The electron paramagnetic resonance spectroscopic investigation of VO(II)-doped zinc ammonium trihydrogen bis(orthophosphate) monohydrate single crystal has been carried out at 300K. The single crystal, rotated along the three orthogonally crystallographic axes, have yielded spin Hamiltonian parameters g and A as: g(xx)=1.978, g(yy)=1.974, g(zz)=1.925 and A(xx)=7.4, A(yy)=7.8, A(zz)=19.4 mT. These spin Hamiltonian parameters reflect a slight deviation from axially symmetry to rhombic, which is elucidated by the interstitial occupation of the vanadyl ion. The isofrequency plots and EPR spectra at few orientations have been simulated using the calculated spin Hamiltonian parameters. The Fermi contact parameter (kappa) and dipolar interaction parameter (P) have been calculated as 0.857 and -128 x 10(-4)cm(-1), respectively. The percentage of metaloxygen bond has been identified as 20%.
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84
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Velavan K, Venkatesan R, Sambasiva Rao P. Identification of static JT in copper(II) doped hexaimidazole M(II) lattices: M=Co and Ni: an EPR study. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2005; 62:494-9. [PMID: 16257752 DOI: 10.1016/j.saa.2005.02.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2004] [Revised: 02/07/2005] [Accepted: 02/07/2005] [Indexed: 05/05/2023]
Abstract
Single crystal EPR studies on Cu(II) doped paramagnetic host lattices, hexaimidazole M(II) dichloride tetrahydrate (M=Co and Ni), isomorphous with M=Zn, have been carried out from room temperature to 77K to understand the nature of Jahn-Teller (JT) distortion in these paramagnetic host systems. The paramagnetic impurity, doped in the present two paramagnetic host lattices, shows anisotropic EPR spectra with superhyperfine from ligands, even at room temperature. An interesting observation noticed in the EPR spectra at room temperature is that there are more resonances corresponding to the second site in the paramagnetic hosts than in the diamagnetic host at 4.2K. This difference in behavior between the diamagnetic and paramagnetic host lattices indicates a change in the depth of the JT valleys. The spin Hamiltonian parameters are evaluated for Cu(II) ion in both the host lattices and the relaxation times have been calculated for the ion in cobalt host lattice only.
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85
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Nagarajan P, Venkatesan R, Kumar MJM, Seshadri SJ, Majumdar SS. Multiple lipomas in a bonnet monkey (Macaca radiata). Vet Res Commun 2005; 29:415-20. [PMID: 16195936 DOI: 10.1007/s11259-005-9476-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/28/2004] [Indexed: 11/27/2022]
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86
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Deepa S, Velavan K, Sougandi I, Venkatesan R, Sambasiva Rao P. Single crystal EPR study of VO(II) in magnesium potassium phosphate hexahydrate: a case of two substitutional vanadyl ions. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2005; 61:2482-7. [PMID: 16043041 DOI: 10.1016/j.saa.2004.09.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2004] [Revised: 09/15/2004] [Accepted: 09/16/2004] [Indexed: 05/03/2023]
Abstract
Single crystal EPR study of VO(II)-doped magnesium potassium phosphate hexahydrate has been carried out at room temperature. Single crystal rotations in the three orthogonal planes indicate that the paramagnetic impurity has entered the lattice in place of magnesium ions by replacing the equatorial and axial coordinated water molecules. The spin Hamiltonian parameters obtained for the two substitutional sites are: site 1: g1=1.9800, g2=1.9774, g3=1.9296, A1=7.25 mT, A2=8.09 mT, A3=18.69 mT and site 2: g1=1.9802, g2=1.9765, g3=1.9296, A1=6.82 mT, A2=8.48 mT, A3=18.75 mT, respectively. Superhyperfine, from protons of ligand water molecules, has been observed at certain orientations. It has been concluded that VO bond directions of the two substitutional ions are orthogonal to each other.
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Nagarajan P, Venkatesan R, Kumar MJM, Majumdar SS. Granulosa theca cell tumor with luteoma in the ovary of a bonnet monkey (Macaca radiata). J Med Primatol 2005; 34:219-23. [PMID: 16053501 DOI: 10.1111/j.1600-0684.2005.00108.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A mass was identified on the left caudal region of the abdomen in a 13-year-old bonnet monkey (Macaca radiata). The mass was excised and diagnosed as granulosa theca cell tumor accompanied with luteoma based on the microscopic findings. Morphologically it appeared pink, round, firm multilobulated measured approximately 5 x 3 x 2.5 cm in dimension. Histologically the luteoma composed of polyhedral cells with pale strained vacuolated cytoplasm, centrally located nuclei with distinct cytoplasmic borders. Granulosa theca cell tumor appeared as densely packed spindle shaped fusiform cells arranged in interlacing bundles and whorled pattern with neoplastic cells appearing irregular shaped solid sheets. The concomitant development of granulosa theca cell tumor with luteoma in a single ovary is very rare and is the first reported case in a bonnet macaque to our knowledge.
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Latha G, Senthilvadivu S, Venkatesan R, Rajendran V. Sound of shallow and deep water lobsters: measurements, analysis, and characterization. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2005; 117:2720-3. [PMID: 15957741 DOI: 10.1121/1.1893525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
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89
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Anandalakshmi H, Sougandi I, Velavan K, Venkatesan R, Rao PS. Single crystal EPR studies of paramagnetic ions doped zinc potassium phosphate hexahydrate; Part III: Mn(II)-a case of rhombic distortion. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2004; 60:2661-2666. [PMID: 15294257 DOI: 10.1016/j.saa.2004.01.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2003] [Accepted: 01/07/2004] [Indexed: 05/24/2023]
Abstract
Single crystal electron paramagnetic resonance (EPR) studies of Mn(II) doped zinc potassium phosphate hexahydrate have been carried out at room temperature. Single crystal rotations along the three orthogonal axes indicate orthorhombic symmetry with spin-Hamiltonian parameters as: g(xx) = 1.9997; g(yy) = 1.9538; g(zz) = 1.9524, D(xx) = 15.49 mT; D(yy) = 0.22 mT; D(zz) = -15.71 mT, A(xx) = 11.70 mT; A(yy) = 10.53 mT; A(zz) = 10.42 mT and a = 0.8 x 10(-4) cm(-1). A large E term indicates considerable distortion from axial symmetry. The impurity is found to enter the lattice substitutionally. The distortion axis for the impurity has been identified along one of the Zn-O bond directions in the crystal.
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90
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Sougandi I, Venkatesan R, Rao PS. Single crystal EPR study of Cu(2+) in cobalt ammonium phosphate hexahydrate: a case of low hyperfine coupling constant and measurement of spin-lattice relaxation times. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2004; 60:2653-2660. [PMID: 15294256 DOI: 10.1016/j.saa.2004.01.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2003] [Accepted: 01/07/2004] [Indexed: 05/24/2023]
Abstract
Single crystal electron paramagnetic resonance (EPR) studies of Cu(II) doped cobalt ammonium phosphate hexahydrate have been carried out from 300 to 77 K, with single crystal rotation in all the three planes at 153 K, since the spectra are well resolved at this temperature. The angular variation studies indicate only one site in substitutional position with spin-Hamiltonian parameters as g: 2.404, 2.155, 2.063 and A: 11.58, 3.49, 2.07 mT. The reduction in one of the principal A value has been explained by considering considerable admixture of d(x(2)-y(2)) ground state with d(zeta(2)) excited state. The admixture coefficients of ground state wave function are: a = 0.2500; b = 0.9663; c = 0.0520; d = 0.0210; e = -0.0210, where a and b correspond to admixture coefficients for d(zeta(2)) and d(x(2)-y(2)) , respectively. Parameters kappa = 0.5140; P = 113 X 10(-4) cm(-1); alpha(2) = 0.7897; alpha = 0.8887; and alpha' = 0.5262 have also been calculated, indicating considerable covalency. The powder spectrum at room temperature is unresolved, whereas it is better resolved at 77 K, with spin-Hamiltonian parameters matching well with the single crystal values of 153 K. Powder spectrum at 77 K has been simulated, which agrees with the experimental one. The spin-lattice relation times are measured from the line width of the resonance lines recorded at different temperature.
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Mahesh Kumar MJ, Nagarajan P, Venkatesan R, Sakthivelan SM, Majumdar SS. Sebaceous gland adenoma in a rhesus monkey (Macaca mulatta). J Med Primatol 2004; 33:214-8. [PMID: 15271070 DOI: 10.1111/j.1600-0684.2004.00072.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A tumor mass was identified below the shoulder region of a 5-year-old male rhesus monkey (Macaca mulatta). The mass was excised and diagnosed as sebaceous gland adenoma based on the microscopic findings. Morphologically it appeared as an elevated, dome-shaped, circumscribed mass of 3.6 x 2.8 x 3.2 cm in dimension with tan speckled color. Histologically, the tumor was composed of mature, sebaceous cells (sebocytes), basal cells arranged in a mass of irregular shapes and sizes, with a characteristic appearance of poly or multilobular structure. Sebocytes were well differentiated with foamy cytoplasm in the center of the lobules and poorly or undifferentiated densely staining basal cells in the periphery of the lobules. Cellular changes in the adjacent lymph node included hyperplasia of plasma cells, macrophages and lymphoid elements with typical mitosis.
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Velavan K, Ravikumar RVSSN, Venkatesan R, Sambasiva Rao P. Identification of crystal symmetry in Kramers and non-Kramers ions by optical absorption: Divalent copper and nickel ions in diamagnetic lattices. CRYSTAL RESEARCH AND TECHNOLOGY 2004. [DOI: 10.1002/crat.200310209] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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93
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Srinivasan R, Sougandi I, Velavan K, Venkatesan R, Verghese B, Sambasiva Rao P. Synthesis and characterization of [Cu2(L)2(OCOCH3)(OCH3)]ClO4 {L=2-[(4-methyl-pyridin-2-ylimino)-methyl]-phenol}: EPR and X-ray studies. Polyhedron 2004. [DOI: 10.1016/j.poly.2004.01.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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94
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Anandalakshmi H, Venkatesan R, Sambasiva Rao P. Effect of lattice defects in divalent lattices by incorporating trivalent ions in biominerals: An EPR study of Cr(III) in zinc(II) potassium phosphate hexahydrate. CRYSTAL RESEARCH AND TECHNOLOGY 2004. [DOI: 10.1002/crat.200310152] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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95
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Deivanayagam CN, Rajasekaran S, Venkatesan R, Mahilmaran A, Ahmed PRK, Annadurai S, Kumar S, Chandrasekar C, Ravichandran N, Pencillaiah R. Prevalence of acquired MDR-TB and HIV co-infection. THE INDIAN JOURNAL OF CHEST DISEASES & ALLIED SCIENCES 2002; 44:237-42. [PMID: 12437236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
BACKGROUND Mounting prevalence of primary and acquired multidrug-resistant tuberculosis in India is a sorry reminder of all round failure in our fight against tuberculosis and also of the necessity for new effective strategies. OBJECTIVES (1) To assess the prevalence and pattern of drug resistant pulmonary tuberculosis among treated patients or on those on treatment without adequate response and (2) to evaluate HIV seropositivity among MDR-TB patients. METHODS Pulmonary TB patients, who had at least six months of unsuccessful anti-tuberculous treatment were selected for the study. Their sputum specimens were examined for M. tuberculosis culture and drug sensitivity pattern and serological examinations for HIV infection were carried out. RESULTS Sputum specimens of 618 patients' (61.8%) of a total of 1000 examined had shown culturable M. tuberculosis. Four hundred ninty-five patients (49.5%) were found to expectorate tubercle bacilli resistant to one or more anti TB drugs. MDR-TB was detected in 339 patients (33.9%). HIV seropositivity among MDR-TB was 4.42%. Significantly, 245 patients (24.5%) had tubercle bacilli resistant to one or more reserve drugs too (ethionamide, kanamycin and/or ofloxacin). CONCLUSIONS Prevalence of MDR-TB was high in the study population. It is essentially an acquired condition. Its association with HIV disease was at present on the lower side, an observation contrary to published western literature. Higher rates of resistance for reserve drugs (ethionamide, kanamycin and/or ofloxacin) in patients who never had these drugs in their earlier treatment schedules suggest the possibility of emerging spontaneous drug resistant mutants.
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Sougandi I, Rajendiran TM, Venkatesan R, Rao PS. Single crystal EPR study of VO(II)-doped cadmium potassium phosphate hexahydrate: A substitutional incorporation. J CHEM SCI 2002. [DOI: 10.1007/bf02704190] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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97
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Govindasamy L, Rajakannan V, Velmurugan D, Shanmuga Sundara Raj S, Rajendran TM, Venkatesan R, Srinivasan R, Fun HK. Crystal Structure of Dimeric Cu(II) Complex {μ,μ'-acetato O,O bis [N-salicylidene-2-amino-pyridine-methanolato N,N,O]} : perchlorate. CRYSTAL RESEARCH AND TECHNOLOGY 2002. [DOI: 10.1002/1521-4079(200209)37:9<1018::aid-crat1018>3.0.co;2-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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98
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Shiyamala C, Rajendiran TM, Venkatesan R, Sambasiva Rao P. Host Lattice Effect on Paramagnetic Impurity: Single Crystal EPR Study of VO(II)-Doped Biomineral Cadmium Ammonium Phosphate Hexahydrate. CRYSTAL RESEARCH AND TECHNOLOGY 2002. [DOI: 10.1002/1521-4079(200208)37:8<841::aid-crat841>3.0.co;2-i] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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99
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Ravikumar RV, Madhu N, Chandrasekhar AV, Reddy BJ, Reddy YP, Sambasiva Rao P, Rajendiran TM, Venkatesan R. Single crystal EPR and optical studies of paramagnetic ions doped zinc potassium phosphate hexahydrate--part II: VO(II)--a case of substitutional site. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2001; 57:2789-2794. [PMID: 11789880 DOI: 10.1016/s1386-1425(01)00471-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Single crystal electron paramagnetic resonance (EPR) studies were carried at room temperature for VO(II) doped zinc potassium phosphate hexahydrate. The results indicate that the paramagnetic impurity has entered the lattice only substitutionally, as confirmed by the single crystal rotations. The spin Hamiltonian parameters calculated from the spectra are g parallel = 1.9356, g perpendicular = 1.9764, A parallel = 200.9 G and A perpendicular = 76.5 G. The optical absorption spectrum exhibits three bands (800, 670 and 340 nm) suggesting the C4v symmetry and the optical parameters evaluated are Dq = 1492, Ds = -3854 and Dt = 186 cm(-1).
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Sambasiva Rao P, Rajendiran TM, Venkatesan R, Madhu N, Chandrasekhar AV, Reddy BJ, Reddy YP, Ravikumar RV. Single crystal EPR and optical studies of paramagnetic ions doped zinc potassium phosphate hexahydrate--part I: Cu(II)--a case of orthorhombic symmetry. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2001; 57:2781-2787. [PMID: 11789879 DOI: 10.1016/s1386-1425(01)00465-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Single crystal electron paramagnetic resonance (EPR) studies on Cu(II) doped zinc potassium phosphate hexahydrate (ZPPH) were carried out at room temperature. The angular variation spectra in the three orthogonal planes indicate that the paramagnetic impurity has entered the lattice substitutionally in place of Zn(II) and the spin Hamiltonian parameters calculated from these spectra are g(xx) = 2.188, g(yy) = 2.032, g(zz) = 2.373, Axx = 50 G, Ayy = 65.0 G and Azz = 80 G. The g and A tensors were coincident and these values matched fairly well with the values obtained from powder spectrum. The bonding parameters have also been calculated.
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