Wang D.,MOE Key Laboratory of Environment and Health |
Hu X.,MOE Key Laboratory of Environment and Health |
Hou Y.,Yunnan University |
Zhong Y.,MOE Key Laboratory of Environment and Health |
And 3 more authors.
Journal of Agricultural and Food Chemistry | Year: 2010
Pu-erh teas are believed to be beneficial beverages for health since they possess several pharmacological properties such as antioxidation, hypocholesterolemia, and antiobesity properties, but their potential toxicities when administered at a high dose as concentrated extracts have not been completely investigated. In this study, the chemical components in Pu-erh green tea and Pu-erh black tea were analyzed and compared, and the safety of tea extracts was evaluated in Wistar rats. The polysaccharide, tea pigment, and flavonoid levels were substantially increased in the Pu-erh black tea, while the polyphenol and free amino acid levels were higher in unfermented green tea. Low toxicities of Pu-erh green tea extract (GTE) were observed at doses of 2500 and 5000 mg/kg/day with a 28-day subacute study. Serum biochemical data including alanine aminotransferase increased to 5000 mg/kg/day GTE males, and creatinine (Cr) increased in all 5000 mg/kg/day GTE groups and 2500 mg/kg/day GTE males. Slight bile duct hyperplasia in the liver was also observed. The target organs of GTE were considered to be the liver and kidney. Comparatively, no adverse effects were observed in Pu-erh black tea extract (BTE)-treated rats. In conclusion, a dose of 1250 mg/kg/day for GTE and 5000 mg/kg/day for BTE following oral administration could be considered safe under the conditions of this study. © 2009 American Chemical Society.
Tang J.,Guangzhou University |
Yang W.,MOE Key Laboratory of Environment and Health |
Ahmed N.I.,Huazhong University of Science and Technology |
Ma Y.,Guangzhou Women and Children Medical Center |
And 5 more authors.
Medicine (United States) | Year: 2016
Stressful life events have been implicated in the etiology of kinds of psychopathology related to nonsuicidal self-injury (NSSI); however, few studies have examined the association between NSSI and stressful life events directly in Chinese school adolescents. In this study, we aim to estimate the prevalence rate of NSSI and examine its association with stressful life events in Southern Chinese adolescents. A total sample of 4405 students with age ranged from 10 to 22 years was randomly selected from 12 schools in 3 cities of Guangdong Province, China. NSSI, stressful life events, self-esteem, emotional management, and coping methods were measured by structured questionnaires. Multinomial logistic regression was used to examine the association of NSSI with stressful life events. Results showed the 1 year self-reported NSSI was 29.2%, with 22.6% engaged in "minor" NSSI (including hitting self, pulling hair, biting self, inserting objects under nails or skin, picking at a wound) and 6.6% in "moderate/sever" NSSI (including cutting/carving, burning, self-tattooing, scraping, and erasing skin). Self-hitting (15.9%), pulling hair out (10.9%), and self-inserting objects under nails or skin picking areas to dram blood (18.3%) were the most frequent types of NSSI among adolescents. Results also showed that "Minor NSSI" was associated with stressful life events on interpersonal, loss and health adaption, and "moderate/severe NSSI" was associated with life events on interpersonal, health adaption in Southern Chinese adolescents, even after adjusted for sex, age, residence, selfesteem, coping style, and emotional management. Results further suggested stressful life events were significantly associated with less risk of NSSI in those who had good emotional management ability. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved.