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571.
A modified spectrophotometric assay of superoxide dismutase 总被引:18,自引:0,他引:18
572.
Abstract Rapid growth of the urban population, particularly in developing countries, places an enormous pressure on water. Sewage farming is common in all urban areas in India. This study is an attempt to evaluate the effect of diluted sewage wastewater irrigation on cultivation of Eleusine coracana and Zea mays from selected semi-urban and rural areas of Coimbatore, Tamil Nadu. For this, parameters analyzed were water/soil quality, crop quality, and mineral analysis including heavy metal composition and in vitro antioxidant potential. From the results, the physicochemical parameters of both rural and semi-urban wastewater samples are within the permissible limits according to the WHO. In mineral analysis, the heavy metals such as Pb, Fe, and Zn are high in all samples and Ni, Cr, and Cu are within the permissible limits in rural samples but slightly high in semi-urban samples. The proximate composition provides general overview of the nutritional value of a food. E. coracana and Z. mays samples collected from rural area show adequate mineral profile required for growth and nutrition. Both the samples show significant antioxidant values significant at p < 0.05. The results demonstrated that the diluted sewage wastewater has physicochemical properties for safe irrigation. Micronutrient and heavy metal contents in the plant samples were not extremely high and were within the range of FAO/WHO standards. 相似文献
573.
J Singh M U Beg P N Viswanathan S H Zaidi 《Environmental physiology & biochemistry》1975,5(4):267-272
The changes in the activities of some mitochondrial and soluble enzymes in the lungs of guinea pig, caused by three varieties of asbestos dust 120 days after intratracheal injection, were studied. Marked increase was observed in mitochondrial cytochrome oxidase, diaphorase and malic dehydrogenase. Among the soluble enzymes, lactic dehydrogenase showed the maximum variation. 相似文献
574.
Valproate (VPA) was administered to four rhesus monkeys by constant-rate intravenous infusion for two weeks under controlled conditions. Plasma and CSF samples were collected for a period of 27 hours at 3-hour intervals during steady-state and post-infusion periods. The mean correlation coefficient between total plasma and CSF VPA concentrations was found to be 0.78 +/- 0.09. The CSF VPA levels reflected the changes in free VPA in plasma but the two were not equivalent. Diurnal fluctuations in CSF VPA concentration were similar to those found in plasma but the inter-animal variation was greater in CSF than in plasma. 相似文献
575.
Gomathy Baskar Thirunavukkarasu Palaniyandi Sandhiya Viswanathan Mugip Rahaman Abdul Wahab Hemapreethi Surendran Maddaly Ravi Asha Sivaji Barani Kumar Rajendran Sudhakar Natarajan Gopu Govindasamy 《Biotechnology and bioengineering》2023,120(11):3105-3115
Oral cancer is a common and deadly kind of tissue invasion, has a high death rate, and may induce metastasis that mostly affects adults over the age of 40. Most in vitro traditional methods for studying cancer have included the use of monolayer cell cultures and several animal models. There is a worldwide effort underway to reduce the excessive use of laboratory animals since, although being physiologically adequate, animal models rarely succeed in exactly mimicking human models. 3D culture models have gained great attention in the area of biomedicine because of their capacity to replicate parent tissue. There are many benefits to using a drug delivery approach based on nanoparticles in cancer treatment. Because of this, in vitro test methodologies are crucial for evaluating the efficacy of prospective novel nanoparticle drug delivery systems. This review discusses current advances in the utility of 3D cell culture models including multicellular spheroids, patient-derived explant cultures, organoids, xenografts, 3D bioprinting, and organoid-on-a-chip models. Aspects of nanoparticle-based drug discovery that have utilized 2D and 3D cultures for a better understanding of genes implicated in oral cancers are also included in this review. 相似文献
576.
Ngozi P. Paul Thiruselvam Viswanathan Jian Chen Masafumi Yoshinaga Barry P. Rosen 《Molecular microbiology》2023,119(4):505-514
The pentavalent organoarsenical arsinothricin (AST) is a natural product synthesized by the rhizosphere bacterium Burkholderia gladioli GSRB05. AST is a broad-spectrum antibiotic effective against human pathogens such as carbapenem-resistant Enterobacter cloacae. It is a non-proteogenic amino acid and glutamate mimetic that inhibits bacterial glutamine synthetase. The AST biosynthetic pathway is composed of a three-gene cluster, arsQML. ArsL catalyzes synthesis of reduced trivalent hydroxyarsinothricin (R-AST-OH), which is methylated by ArsM to the reduced trivalent form of AST (R-AST). In the culture medium of B. gladioli, both trivalent species appear as the corresponding pentavalent arsenicals, likely due to oxidation in air. ArsQ is an efflux permease that is proposed to transport AST or related species out of the cells, but the chemical nature of the actual transport substrate is unclear. In this study, B. gladioli arsQ was expressed in Escherichia coli and shown to confer resistance to AST and its derivatives. Cells of E. coli accumulate R-AST, and exponentially growing cells expressing arsQ take up less R-AST. The cells exhibit little transport of their pentavalent forms. Transport was independent of cellular energy and appears to be equilibrative. A homology model of ArsQ suggests that Ser320 is in the substrate binding site. A S320A mutant exhibits reduced R-AST-OH transport, suggesting that it plays a role in ArsQ function. The ArsQ permease is proposed to be an energy-independent uniporter responsible for downhill transport of the trivalent form of AST out of cells, which is oxidized extracellularly to the active form of the antibiotic. 相似文献
577.
Kumar Rajeev Harikrishna Barman Dipankar Ghimire Om P. Gurumurthy S. Singh Pradeep K. Chinnusamy Viswanathan Padaria Jasdeep C. Arora Ajay 《Plant Growth Regulation》2022,96(1):67-78
Plant Growth Regulation - The present study was conducted to evaluate the effect of a stay-green trait to stabilize the yield responses under combined heat and drought stress on wheat. Ten... 相似文献
578.
Manape Tushar Kashinath Satheesh Viswanathan Singh Shweta Singh Major Anandhan Sivalingam 《Plant Cell, Tissue and Organ Culture》2022,148(1):61-72
Plant Cell, Tissue and Organ Culture (PCTOC) - A high-auxin medium, usually used for callus induction, was not effective for Indian short-day onion cv. Bhima super. In this study, we found that the... 相似文献
579.
580.
V P Chandrasekaran R Viswanathan T A Venkitasubramanian 《Environmental physiology & biochemistry》1975,5(6):373-377
The effect of hypobaric hypoxia on the activities of glutamine synthetase, glutaminase and cyclic 3'5' AMP phosphodiesterase in rat brain was studied after exposure to 25,000' for 6 h. Glutamine synthetase activity was increased in all the regions of brain studied, and addition of gamma amino butyric acid, serotonin and cortisol in vitro produced a differential response. Glutaminase activity decreased in the whole brain. Cyclic 3'5' AMP phosphodiesterase activity decreased in cerebellum, medulla, hypothalamus and pituitary showing an accumulation of cyclic 3'5' AMP in these regions. The results suggest that glutamine synthesis and degradation are regulated in the central nervous system by cyclic AMP and cortisol: Gamma aminoburyric acid and other compounds can modulate the activity of glutamine synthetase and glutaminase. 相似文献