Serum activity of mitochondrial aspartate aminotransferase and extrahepatic cholestasis

Serum mitochondrial aspartate aminotransferase (mAST) level and the mitochondrial aspartate aminotransferase/total aspartate aminotransferase ratio (mAST/AST) have been proposed as sensitive markers of chronic alcoholism. Their specificity, however, remains poorly defined. The purpose of this study was to compare these markers in three groups of hospitalized patients: group I, 80 patients with chronic alcoholic liver disease; group II, 51 patients with chronic liver disease without alcoholism; group III, 44 patients with extrahepatic cholestasis (due to choledocholithiasis in 21 and malignant in 23). mAST was measured after immuno-precipitation of cytoplasmic aspartate aminotransferase. The normal values of mAST (less than or equal to 2 mu/l) and mAST/AST (less than or equal to 6 p. 100) were defined in a group of 59 non alcoholic subjects without liver disease (controls). mAST was increased as compared with controls in 91 p. 100 of the patients of group I, 20 p. 100 of group II, 61 p. 100 of group III. mAST was comparable in groups I (mean +/- SD: 10 +/- 10.8) and III (10.3 +/- 12.9), and higher than in group II (1.8 +/- 2.4). m/AST was increased in 59 p. 100 of the patients of group I, 6 p. 100 of group II and 36 p. 100 of group III. It was higher in group I (8 +/- 4 p. 100) than in group III (6 +/- 4 p. 100, p less than 0.02), and particularly higher in both these groups than in group II (2 +/- 1 p. 100, p less than 0.00001). mAST was correlated to AST in each of these three groups.(ABSTRACT TRUNCATED AT 250 WORDS)     

Biomarkers of folate and vitamin B12 and breast cancer risk: report from the EPIC cohort

Epidemiological studies have reported inconsistent findings for the association between B vitamins and breast cancer (BC) risk. We investigated the relationship between biomarkers of folate and vitamin B12 and the risk of BC in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Plasma concentrations of folate and vitamin B12 were determined in 2,491 BC cases individually matched to 2,521 controls among women who provided baseline blood samples. Multivariable logistic regression models were used to estimate odds ratios by quartiles of either plasma B vitamin. Subgroup analyses by menopausal status, hormone receptor status of breast tumors (estrogen receptor [ER], progesterone receptor [PR] and human epidermal growth factor receptor 2 [HER2]), alcohol intake and MTHFR polymorphisms (677C > T and 1298A > C) were also performed. Plasma levels of folate and vitamin B12 were not significantly associated with the overall risk of BC or by hormone receptor status. A marginally positive association was found between vitamin B12 status and BC risk in women consuming above the median level of alcohol (OR_Q4‐Q1 = 1.26; 95% CI 1.00–1.58; P_trend = 0.05). Vitamin B12 status was also positively associated with BC risk in women with plasma folate levels below the median value (OR_Q4‐Q1 = 1.29; 95% CI 1.02–1.62; P_trend = 0.03). Overall, folate and vitamin B12 status was not clearly associated with BC risk in this prospective cohort study. However, potential interactions between vitamin B12 and alcohol or folate on the risk of BC deserve further investigation.     

Serum carotenoid,tocopherol and retinol concentrations and breast cancer risk in the E3N‐EPIC study

Evidence of a protective effect of fruit and vegetable intake on breast cancer risk is inconsistent. Epidemiologic cohort studies based on blood carotenoid intakes as biomarkers of consumption of fruits and vegetable in individuals are still scare and findings are discrepant. The study population included women in the E3N Study, the large French component of the European Prospective Investigation into Cancer and Nutrition (EPIC). During an average of 7 years follow‐up, 366 cases of incident invasive breast cancer (84 premenopausal women and 282 postmenopausal women) among 19,934 women who completed a dietary questionnaire and had available blood samples at baseline (1995–1998) were included in the study. Controls were randomly matched on age, menopausal status at blood collection, fasting status at blood collection, date and collection center. Serum carotenoids, tocopherols and retinol concentrations were assessed by high pressure liquid chromatography. Odds ratios for breast cancer risk adjusted for established breast cancer risk factors were calculated by quintile of serum micronutrient concentrations. No significant associations between breast cancer risk and serum carotenoids (highest versus lowest quintile, odds ratio (OR) = 0.74, 95% confidence interval (CI) = 0.47–1.16, p for trend 0.38), tocopherols (OR = 0.68, 95% CI = 0.41–1.10, p for trend 0.26) and retinol (OR = 0.85, 95% CI = 0.53–1.35, p for trend 0.34) were found. Our findings did not support the hypothesis that lipophilic antioxidant micronutrients found in fruits and vegetables protect against breast cancer, at least in postmenopausal women.     

报告非药物随机对照临床试验的CONSORT扩展声明：说明与详述（一）

正确报告随机对照临床试验（randomized controlled trial,RCT）是严格评价试验结果真实性与有效性的必要前提。含22项条目清单和流程图的CONSORT（Consolidated Standards of Reporting Trials）声明旨在通过改进RCT的报告来解决这一问题。然而,《CONSORT声明》中没有专门论及那些适用于非药物治疗（如手术、技术干预、仪器设备、康复理疗、心理治疗和行为干预等）临床试验的具体问题。此外,相当多的证据表明非药物临床试验的报告仍然需要改进,因此CONSORT小组针对评估非药物治疗的临床INFORMATION FOR AUTHORS试验制定了《CONSORT扩展声明》。为制定《CONSORT扩展声明》以规范非药物临床试验的报告,33名专家于2006年2月在法国巴黎组织召开了讨论会议,并就此达成了共识。与会者扩充了原有《CONSORT声明》中的11项条目,新增了1项条目,修改并重新制定了报告流程图。 为便于充分理解和执行《CONSORT扩展声明》,CONSORT小组通过对文献的回顾编制了这一说明与详述文本,旨在为正确报告非药物临床试验提供范例。本扩展声明,连同《CONSORT声明》以及《CONSORT声明》的其他扩展本,将有助于改进非药物治疗领域RCT的报告。