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41.
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
42.
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
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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
45.
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
46.
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
47.
Mahalakshmi Vijayaraghavan Sengupta Prattusha Sumantran V. N. Suganya Natarajan Chatterjee Suvro 《Cell and Tissue Biology》2020,14(6):448-457
Cell and Tissue Biology - Besides disease condition, very few stress stimulants were determined to provoke red blood cell (RBC) adhesion to endothelial cells (EC). However, the possible role of... 相似文献
48.
Baruah Indrani Baruah Geetanjali Sahu Jagajjit Singha Dhanawantari L. Dekaboruah Hariprasanna Velmurugan Natarajan Chikkaputtaiah Channakeshavaiah 《Plant Molecular Biology Reporter》2021,39(2):471-471
Plant Molecular Biology Reporter - The affiliation 2 in the published article was Academy of Scientific and Innovative Research (AcSIR), CSIR-NEIST Campus, Jorhat, Assam 785,006, India. 相似文献
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Natarajan Suganthy Shanmugiahthevar Karutha Pandian 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):702-707
Alzheimer's disease is a progressive neurodegenerative illness accounting for approximately 50% of all types of dementia in elderly people. The only symptomatic treatment proven effective to date is the use of cholinesterase inhibitors to augment surviving cholinergic activity. The purpose of this study is to investigate cholinesterase inhibitory activity of mangroves as an alternative medicine for the treatment of Alzheimer's disease. About nine mangrove plants, which were used as folk medicine in tropical countries, were collected from Parangipettai, Vellar estuary, Tamilnadu, India. Nile Tilapia muscle homogenate was used as source of enzyme. Inhibitory effect of methanolic leaf extract was assessed under in vitro condition by incubating various concentration of the extract with total cholinesterase and butyryl cholinesterase and assessing their residual activities by Ellman's colorimetric method. The results showed that of the nine plants screened Rhizophora lamarckii, Suaeda monica, Avicennia officinalis and Sesuvium portulacastrum showed 50% inhibitory activity to both TChE and BChE at concentrations less than 2 mg/mL when compared to other plant extracts, which was comparable to the standard drug Donepezil. Phytochemical analysis showed the presence of alkaloids in high concentration which might be correlated to its cholinesterase inhibitory activity. 相似文献