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991.
The DNA:histone ratios have been determined by quantitative cytochemical analyses of individual cells in populations of human lymphocytic cells derived in continuous culture from the peripheral blood buffy coats of patients with acute leukemia or infectious mononucleosis. These populations of lymphocytic cells were quite similar with respect to the Feulgen-DNA and protein content per cell. The close association between DNA and histone was reflected in their similar patterns of distribution in fixed and stained cells; and further evidenced by similarities in the DNA: histone ratios characteristic of these different populations of lymphocytic cells. — Chemical acetylation and methylation of nuclear proteins of these cell populations exhibited some quantitative differences. The chemically acetylated histone content was less, and chemically methylated histone content was greater in cells derived from acute leukemia or infectious mononucleosis than in normal human lymphocytes. These quantitative differences in chemical acetylation and methylation may contribute to specific structural alterations in these histones which modify their functional capacity with respect to interactions with DNA. Such alterations may relate to differences in gene expression as reflected, for example, by the biological and biochemical differences among these human lymphocytic cells.These studies were supported in part by research grants C-6516 from the National Cancer Institute and FR-05526 from the Division of Research Facilities and Resources, National Institutes of Health.Holds Research Career Award K6-CA-22,150 from the National Cancer Institute, National Institutes of Health. 相似文献
992.
993.
Vanita Noronha Kumar Prabhash Abhishek Thavamani Anuradha Chougule Nilendu Purandare Amit Joshi Rashmi Sharma Saral Desai Nirmala Jambekar Amit Dutt Rita Mulherkar 《PloS one》2013,8(4)
Screening for EGFR mutation is a key molecular test for management of lung cancer patients. Outcome of patients with mutation receiving EGFR tyrosine kinase inhibitor is known to be better across different ethnic populations. However, frequency of EGFR mutations and the clinical response in most other ethnic populations, including India, remains to be explored. We conducted a retrospective analysis of Indian lung cancer patients who were managed with oral tyrosine kinase inhibitors. Majority of the patients in the study had adenocarcinoma and were non-smokers. 39/111 patients tested positive for EGFR kinase domain mutations determined by Taqman based real time PCR. The overall response to oral TKI therapy was 30%. Patients with an activating mutation of EGFR had a response rate of 74%, while the response rate in patients with wild type EGFR was 5%, which was a statistically significant difference. Progression free survival of patients with EGFR mutations was 10 months compared to 2 months for EGFR mutation negative patients. Overall survival was 19 months for EGFR mutation patients and 13 months for mutation negative patients. This study emphasizes EGFR mutation as an important predictive marker for response to oral tyrosine kinase inhibitors in the Indian population. 相似文献
994.
A R Dhage B B Desai R M Naik S V Munjal M S Naik 《Indian journal of biochemistry & biophysics》1992,29(5):425-427
The redox state of cytochrome alpha 3 during in situ respiration of leaves of 20-day-old rice seedlings was assessed by in vivo aerobic assay of nitrate reductase, after 1 min exposure to carbon monoxide. Different stress treatments like water and salt stresses, disintegration of leaf tissues and darkness modified the redox state of cytochrome c oxidase. The dark treatment altered the redox state of cytochrome oxidase from reduced to the oxidized state, as judged by its reaction with CO in CO-sensitive rice cultivar. The water and salt stresses as well as the disintegration of leaf tissue on the contrary altered cytochrome oxidase from the oxidized to its reduced state in CO-insensitive cultivars; probably by changing the cellular integrity, turgidity and structure of mitochondrial membrane, and also due to decreased mitochondrial energization. 相似文献
995.
The total lipids of axenically cultivated cells of Porphyridium cruentum were extracted with aqueous methanol-chloroform mixture and fractionated into neutral and polar lipids by silicic acid column chromatography. Thin-layer and reversed-phase paper chromatographic analyses of the neutral lipid fractions revealed the occurrence of plastoquinones (PQ) A and C, vitamin K1 (K), ubiquinone-10 (Q10), α-tocopherol (α-T), and α-tocopherolquinone (α-TQ) in the photoautotrophically cultured alga, and the same quinones but no tocopherol in the alga grown photoheterotrophically on glycerol. The plastoquinone A and vitamin K1 were isolated, identified, and estimated by spectroscopic methods. The results indicated the following decreasing order of concentrations: autotrophic culture, PQ A > K > Q10 > PQ C, α-TQ, α-T; heterotrophic culture, PQ A > Q10 > K > PQ C, α-TQ. Except for the absence of plastoquinone B, the overall quinonoid composition was in general agreement with those previously reported for multicellular members of Rhodophyta, but the concentration level in total lipid was markedly lower. 相似文献
996.
997.
N. H. Wadia M. M. Desai E. V. Quadros D. K. Dastur 《BMJ (Clinical research ed.)》1972,3(5821):264-267
Only 20 patients with optic neuritis of unknown aetiology could be collected in Bombay over a period of two and a half years. Only six of them were smokers and only three (one a non-smoker) had bilateral centrocaecal scotomata similar to those found in tobacco amblyopia. In 11 untreated patients the serum vitamin B12 and plasma thiocyanate levels were estimated and found to show no significant differences from those in normal control subjects. Treatment with hydroxocobalamin in the majority of cases and with cyanocobalamin, corticotrophin, or prednisolone in the rest showed equally good results; spontaneous improvement was seen in one case.No significant role could be assigned to smoking (cyanide) or to vegetarianism in the production of optic neuritis in these patients; nor was there any evidence of depletion of total (cyanide-extracted) B12 or of an increase in the proportion of non-cyanide-extracted B12 in the serum. 相似文献
998.
999.
Neutrophil oxidants, in particular hypochlorous acid (HOCl), can cause injury to healthy tissues at sites of inflammation. Some of this injury may be caused by oxidant-induced mobilization of metals. We examined the ability of HOCl to mobilize Zn2+ in target tissues. Arterial endothelial cell cultures and heart tissue sections were incubated for 90 s in buffered saline, pH 7.3, containing a suspension of N-(6-methoxy-8-quinolyl)-p-toluenesulfonamide (100 nmol/mL), a Zn(2+)-specific fluorescent chelator, and were subsequently exposed to 200 microM HOCl for 5 min. The cellular fluorescence was analyzed histologically and showed a marked increase in intensity after HOCl treatment, which was indicative of an increase in cellular free Zn2+ concentration. Incubation of HOCl-treated tissues with dithiothreitol, a membrane-permeable metal chelator, caused a sharp decline in cellular fluorescence. This study shows for the first time that HOCl can mobilize cellular Zn2+. In view of the multiple cellular roles played by Zn2+, its mobilization by oxidants at sites of inflammation may contribute to the observed injury. The ability of dithiothreitol to chelate the mobilized Zn2+ suggests that it may be able to reverse Zn(2+)-mediated injury. 相似文献
1000.