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Das DK 《Antioxidants & redox signaling》2004,6(2):405-412
Thioredoxins are a class of small redox-regulating proteins that appear to play a crucial role in many oxidative stress-inducible degenerative diseases. A recent study demonstrated a reduction of thioredoxin-1 (Trx1) protein in the ischemic reperfused myocardium. When the same heart was adapted to ischemic stress by preconditioning with repeated cyclic episodes of small duration of ischemia and reperfusion, there was an increased induction of Trx1 expression. Inhibition of Trx1 expression resulted in reduced postischemic ventricular recovery and increased myocardial infarct size in the preconditioned heart. Corroborating these findings, transgenic mouse hearts overexpressing Trx1 were resistant to ischemic reperfusion injury as compared with the hearts from wild-type mice. Thus, it appears that thioredoxin plays a crucial role in cardioprotection induced by preconditioning. 相似文献
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The cytologic appearance of epithelioid sarcoma in fine-needle aspiration biopsy cytology (FNABC) smears has not been extensively described. We report a case of epithelioid sarcoma in a 55-year-old male who presented with nodular swellings in the abdominal wall and scrotum. The scrotal swelling was subsequently demonstrated to arise from the vas deferens. We highlight the cytomorphologic, immunocytochemical, and histopathologic features of this rare lesion in an unusual site, with particular emphasis on the dilemma encountered in the cytodiagnosis of this lesion. 相似文献
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We have previously isolated a drug-resistant, [PC3(R)], variant of human prostate PC3 cell line, which showed significant resistance (>10-fold) to adriamycin. No known mechanisms of drug resistance were found; however, resistant cells expressed more bcl2, c-myc, and ms oncogenes compared to the sensitive cells. In this study, we found that buthionine sulfoximine (BSO), an inhibitor of gamma-glutamyl-cysteine synthetase, decreased glutathione levels by 80-90% in both cell lines. BSO treatment down-modulated Ras protein only in PC3(R) cells and caused a 4-fold sensitization of PC3(R) cells to adriamycin without affecting PC3(W) cells. Farnesol treatment also inhibited expression of Ras protein and concomitantly reversed adriamycin resistance in PC3(R) cells, indicating that altered levels of ras expression plays an important role in drug resistance in PC3(R) cells. 相似文献
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The Caribbean Food and Nutrition Institute conducted a survey of anemia status of pregnant and/or lactating women in Jamaica (1982), Montserrat (1981), and St. Vincent and the Grenadines (1985). After various interventions designed to reduce the prevalence of anemia in pregnant women, follow-up surveys were conducted in the same countries five years after the initial surveys to determine whether or not the prevalence of anemia in pregnant women did indeed fall after these interventions. As of July 1984, the Jamaica Flour Mills began fortifying all baking flour and counter flour with iron (44 mg/kg) (a 70% increase in the amount of iron added), thiamine (6.3 mg/kg), riboflavin (3.9 mg/kg), and niacin (52.8 mg/kg). During the five year period following the initial survey in Montserrat, health workers had changed the type of iron administered to pregnant women, a constant supply of iron tablets was established, and the economy had improved. The changes in St. Vincent and the Grenadines were that the government provided a constant supply of iron folate (ferrous folate) tablets and there was a 1988 workshop on a manual on the control of anemia where nurses were trained in better clinic management of anemia. The prevalence of anemia (Hb 11 g/dl) in pregnant women fell from 61.6% to 53% (p 0.09) in Jamaica. It fell from 82.3% to 22.1% in Montserrat (p 0.0001). The prevalence of anemia (Hb 10 g/dl) in pregnant women fell from 25% to 14.5% (p 0.001) in St. Vincent and the Grenadines. These findings show that different interventions may have contributed to the reduction in the prevalence of anemia in pregnant women in Jamaica, Montserrat, and St. Vincent and the Grenadines. 相似文献