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31.
Alterations of Inositol Lipid Metabolism of Rat Sciatic Nerve in Streptozotocin-Induced Diabetes 总被引:9,自引:8,他引:1
Abstract: The composition and metabolism of rat sciatic nerve phospholipids were studied 20 weeks after induction of chronic diabetes by intraperitoneal injection of streptozotocin (50 mg/kg). On a wet weight basis the nerves from the diabetic animals showed a 7% decrease in total phospholipid from that of controls and a relative decrease in phosphatidylinositol. Incubations of isolated sciatic nerves of diabetic rats in a medium containing [33 P]orthophosphate gave decreased labeling of phosphatidylinositol and substantial changes in the labeling pattern of phosphatidylinositol phosphate and 4,5-bisphosphate from that of controls. The ratio of label in these polyphosphoinositides decreased from 2.5 for normal nerve to about 1.0 for diabetic nerve within a 2-h incubation period. These metabolic alterations were not observed in acutely diabetic animals 5 days after streptozotocin (100 mg/kg) administration. Because polyphosphoinositides may be involved in the control of membrane permeability during axonal conduction, alterations in their relative amounts or turnover rates could be related to the physiological changes of early diabetic neuropathy. 相似文献
32.
A T Natarajan A A van Zeeland E A Verdegaal-Immerzeel A R Filon 《Mutation research》1980,69(2):307-317
Chicken embryonic fibroblasts, which possess photoreactivating enzyme were used to study the influence of photoreactivating light on the induction of pyrimidine dimers, sister-chromatid exchanges (SCEs) and chromosomal aberrations by 254 nm UV. While photoreactivation (PR) efficiently removed most of the induced dimers (75-95%), the frequencies of SCEs and chromosomal aberrations were reduced only by about 30-65%, in parallel experiments. Since pyrimidine dimers are the only photoreactivable photolesions known, the reduction in the frequencies of SCEs and chromosomal aberrations on PR has been interpreted as due to disappearance of pyrimidine dimers, implying that these lesions are the primary events responsible for the induction of the biological end points studied. The possible reasons for the lack of quantitative relationship between the frequencies of dimers and the frequencies of SCEs and chromosomal aberrations are discussed. 相似文献
33.
Cytogenetic damage induced by a wide range of concentrations of CNU-ethanol in mice was evaluated by determining the frequencies of (a) micronuclei nuclei in polychromatic erythrocytes of the bone marrow, (b) chromatid aberrations in bone marrow, (c) chromatid aberrations in spermatogonia, and (d) reciprocal translocations induced in spermatogonia and scored in spermatocytes.For CNU-ethanol the following order of sensitivity was found between the tests performed: micronuclei > aberrations in bone marrow > aberrations in spermatogonia > translocations in spermatocytes.Correlation coefficients were calculated for the first three parameters. Positive correlations existed (a) between micronuclei in polychromatic erythrocytes and chromatid aberrations in bone marrow on the first day after treatment, and (b) between chromatid aberrations in bone marrow and spermatogonia at the first day after treatment.Three reciprocal translocations were induced in spermatogonia and recorded in primary spermatocytes; all were of a rare type, namely between an X chromosome and an autosome. 相似文献
34.
The thermal behavior of the California sea lion is modeled by a set of seventeen simultaneous partial differential equations. Numerical solution of these equations yields temperature profiles in the sea lion that closely reproduce experimental data obtained with the animals at rest in air. The model predicts that exercise is necessary to maintain body temperature while immersed in very cold water (0°C) but that very efficient heat conservation occurs during diving because of bradycardia, limited circulation, and absence of respiration. 相似文献
35.
Short treatment (up to 1 h) of cytosine arabinoside (araC) increases the frequencies of aberrations induced by X-rays in human lymphocytes, evaluated at the first mitosis following stimulation, or as prematurely condensed chromosomes of G0 nuclei. Parallel biochemical experiments using nucleoid sedimentation technique, demonstrate that araC inhibits rejoining of DNA-strand breaks effectively. These results point out that X-ray-induced short-lived DNA strand breaks lead to chromosomal aberrations in human lymphocytes. 相似文献
36.
Ramya Krishnan Rahul Ravikumar Menon Naoto Tanaka Hans-Jürgen Busse Srinivasan Krishnamurthi Natarajan Rameshkumar 《PloS one》2016,11(3)
A novel yellow colony-forming bacterium, strain P3B162T was isolated from the pokkali rice rhizosphere from Kerala, India, as part of a project study aimed at isolating plant growth beneficial rhizobacteria from saline tolerant pokkali rice and functionally evaluate their abilities to promote plant growth under saline conditions. The novel strain P3B162T possesses plant growth beneficial traits such as positive growth on 1-aminocyclopropane-1-carboxylic acid (ACC), production of indole acetic acid (IAA) and siderophore. In addition, it also showed important phenotypic characters such as ability to form biofilm and utilization of various components of plant root exudates (sugars, amino acids and organic acids), clearly indicating its lifestyle as a plant rhizosphere associated bacterium. Taxonomically, the novel strain P3B162T was affiliated to the genus Arthrobacter based on the collective results of phenotypic, genotypic and chemotaxonomic analyses. Moreover, molecular analysis using 16S rRNA gene showed Arthrobacter globiformis NBRC 12137T, Arthrobacter pascens DSM 20545T and Arthrobacter liuii DSXY973T as the closely related phylogenetic neighbours, showing more than 98% 16S rRNA similarity values, whereas the recA gene analysis displayed Arthrobacter liuii JCM 19864T as the nearest neighbour with 94.7% sequence similarity and only 91.7% to Arthrobacter globiformis LMG 3813T and 88.7% to Arthrobacter pascens LMG 16255T. However, the DNA-DNA hybridization values between strain P3B162T, Arthrobacter globiformis LMG 3813T, Arthrobacter pascens LMG 16255T and Arthrobacter liuii JCM 19864T was below 50%. In addition, the novel strain P3B162T can be distinguished from its closely related type strains by several phenotypic characters such as colony pigment, tolerance to NaCl, motility, reduction of nitrate, hydrolysis of DNA, acid from sucrose, cell wall sugars and cell wall peptidoglycan structure. In conclusion, the combined results of this study support the classification of strain P3B162T as a novel Arthrobacter species and we propose Arthrobacter pokkalii sp.nov.as its name. The type strain is P3B162T (= KCTC 29498T = MTCC 12358T). 相似文献
37.
38.
Different levels of replacement of thymidine by 5-bromodeoxyuridine in mammalian DNA have been used to analyze restriction endonuclease-dependent induction of sister-chromatid exchanges and chromosomal aberrations. Data regarding enzyme action in whole cells and in isolated nuclei are presented and discussed. The results indicate a lack of correlation between enzyme effectiveness and the degree of 5-bromodeoxyuridine substitution in the target sequences, specific to the tested restriction endonucleases. 相似文献
39.
Arjun H. Ananth Natarajan Manikandan Ravi Kumar Rajan Ramakrishnan Elancheran Kunasekaran Lakshmithendral Muthiah Ramanathan Atanu Bhattacharjee Senthamaraikannan Kabilan 《化学与生物多样性》2020,17(2)
Breast Cancer (BCa) is the most often diagnosed cancer among women who were in the late 1940’s. Breast cancer growth is largely dependent on the expression of estrogen and progesterone receptor. Breast cancer cells may have one, both, or none of these receptors. The treatment for breast cancer may involve surgery, hormonal therapy (Tamoxifen, an aromatase inhibitor, etc.) and oral chemotherapeutic drugs. The molecular docking technique reported the findings on the potential binding modes of the 2‐(2‐bromo‐3‐nitrophenyl)‐5‐phenyl‐1,3,4‐oxadiazole derivatives with the estrogen receptor (PDB ID: 3ERT). The 1,3,4‐oxadiazole derivatives 4a – 4j have been synthesized and described by spectroscopic method. 2‐(2‐Bromo‐6‐nitrophenyl)‐5‐(4‐bromophenyl)‐1,3,4‐oxadiazole ( 4c ) was reconfirmed by single‐crystal XRD. All the compounds have been tested in combination with generic Imatinib pharmaceutical drug against breast cancer cell lines isolated from Caucasian woman MCF‐7, MDA‐MB‐453 and MCF‐10A non‐cancer cell lines. The compounds with the methoxy (in 4c ) and methyl (in 4j ) substitution were shown to have significant cytotoxicity, with 4c showing dose‐dependent activation and decreased cell viability. The mechanism of action was reported by induced apoptosis and tested by a DNA enzyme inhibitor experiment (ELISA) for Methyl Transferase. Molecular dynamics simulations were made for hit molecule 4c to study the stability and interaction of the protein?ligand complex. The toxicity properties of ADME were calculated for all the compounds. All these results provide essential information for further clinical trials. 相似文献
40.
Saikia Banashree Singh Sanjay Debbarma Johni Velmurugan Natarajan Dekaboruah Hariprasanna Arunkumar Kallare P. Chikkaputtaiah Channakeshavaiah 《Physiology and Molecular Biology of Plants》2020,26(5):857-869
Physiology and Molecular Biology of Plants - The recent global climate change has directly impacted major biotic and abiotic stress factors affecting crop productivity worldwide. Therefore, the... 相似文献