Black tea extract: a supplementary antioxidant in radiation-induced damage to DNA and normal lymphocytes.

Myriad research has contributed significantly toward the understanding and identification of health benefits stemming from tea polyphenols and many other naturally occurring flavonoids present in fruits and vegetables. These flavonoids are known to mitigate reactive oxygen species-induced damage by scavenging them. In this study, hot-water black tea extract rich in flavonoids is evaluated as a supplementary antioxidant. The antioxidant efficacy of black tea extract was investigated by evaluating radioprotection conferred to pBR322 DNA, calf thymus DNA, and normal lymphocytes during gamma irradiation. The protection was measured by gel electrophoresis, fluorimetric study, cell viability assay, cytokinesis-blocked micronuclei assay, and comet assay. The 2,2-diphenyl-1-picrylhydrazyl scavenging ability of the tea extract used increased in a dose-dependent manner (IC50: 182.45 µg/mL). Positive correlation of radioprotection with antioxidant activity of black tea extract was observed in all systems. Maximum protection against radiation-induced damage was observed in pBR322 DNA and calf thymus DNA at ≥200 µg/mL of black tea extract. At a dose of black tea extract as low as 5 µg/mL, efficient radioprotection was observed in normal lymphocytes, which is encouraging and can be tested in the future as a natural antioxidant supplement during radiotherapy.

Predictors of buprenorphine-naloxone dosing in a 12-week treatment trial for opioid-dependent youth: secondary analyses from a NIDA Clinical Trials Network study.

INTRODUCTION: The present investigation examines baseline patient characteristics to predict dosing of buprenorphine-naloxone, a promising treatment for opioid addiction in youths. METHODS: This study of 69 opioid-dependent youths is a secondary analysis of data collected during a National Institute on Drug Abuse (NIDA) Clinical Trials Network study. Outpatients aged 15-21 were randomized to a 12-week buprenorphine-naloxone dosing condition (including 4 weeks of taper). Predictors of dosing included sociodemographic characteristics (gender, race, age, and education), substance use (alcohol, cannabis, cocaine, and nicotine use), and clinical characteristics (pain and withdrawal severity). RESULTS: Most (75.4%) reported having either "some" (n=40, 58.0%) or "extreme" (n=12, 17.4%) pain on enrollment. Maximum daily dose of buprenorphine-naloxone (19.7 mg) received by patients reporting "extreme" pain at baseline was significantly higher than the dose received by patients reporting "some" pain (15.0mg) and those without pain (12.8 mg). In the adjusted analysis, only severity of pain and withdrawal significantly predicted dose. During the dosing period, there were no significant differences in opioid use, as measured by urinalysis, by level of pain. CONCLUSION: These data suggest that the presence of pain predicts buprenorphine-naloxone dose levels in opioid-dependent youth, and that patients with pain have comparable opioid use outcomes to those without pain, but require higher buprenorphine-naloxone doses.

Effect of alpha-tocopherol supplementation on renal oxidative stress and Na+/K+ -adenosine triphosphatase in ethanol treated Wistar rats.

Ethanol intoxication resulted in high extent of lipid peroxidation, and reduction in antioxidant defenses (decreased GSH, GSH/GSSG ratio, and catalase, SOD and GPx activities) and (Na+/K+)-ATPase activity in kidney. Alpha-tocopherol treatment effectively protected kidney from ethanol induced oxidative challenge and improved renal (Na+/K+)-ATPase activity. Ethanol induced oxidative stress in the kidney and decreased (Na+/K+)-ATPase activity could be reversed by treatment with ascorbic acid.

Prescription of fixed dose combination drugs for diarrhoea.

Fixed-dose combinations (FDCs) of an antiprotozoal and an antibacterial, for treatment of diarrhoea, have been available in the Indian pharmaceutical market for about a decade. There is little evidence to substantiate this combination therapy. We evaluated 2,163 physician prescriptions for diarrhoea and found that 59 per cent of prescriptions were for FDCs. This is unethical because prescribing such combinations exposes a patient to higher risks of adverse drug reactions and also increases the chances of drug resistance. Physicians' prescribing practices in India are influenced by socioeconomic factors and the pharmaceutical industry's marketing techniques that include giving incentives to physicians to prescribe certain drugs.