Trends in age of smoking initiation among the Chinese population born between 1950 and 1997.

OBJECTIVES: Smoking prevalence has significantly increased among Chinese adolescences in the past decades. The aim of our study is to investigate the trends and changing patterns in age of smoking initiation among the Chinese population. STUDY DESIGN: Pooled data from the 2006-2015 China Health and Nutrition Survey was used for analysis. A total of 10,032 adults aged ≥18 years who were born between 1950 and 1997 were separated into five birth cohorts (1950-1959, 1960-1969, 1970-1979, 1980-1989 and 1990-1997). METHODS: Age-specific (10-24 years) smoking initiation rates were calculated by gender, educational level and urbanisation. The multiple logistic models were used for estimates of changes in smoking initiation age. RESULTS: The mean age of smoking initiation decreased substantially from 22.0 years (95% confidence interval [CI]: 21.2-22.7) to 17.5 years (95% CI: 16.2-19.1) over five generations. A large decrease was seen in the initiation age group of 15-24 years in the 1980s cohort (15-19 years: odds ratio [OR] = 0.57; 95% CI: 0.19-0.97; 20-24 years: OR = 0.45; 95% CI: 0.18-0.82); a significant decrease was also found in the 1990s cohort (15-19 years: OR = 0.47; 95% CI: 0.11-0.94; 20-24 years old: OR = 0.34; 95% CI: 0.14-0.85). The peak age of smoking initiation changed from 20 years old to 18 years old over the five generations. CONCLUSIONS: The age of smoking initiation has decreased rapidly in the Chinese population in the past decades. Chinese adolescents are becoming the main target group for the tobacco marketing industry, and national legislations are urgently required.

Arctigenin Attenuates Ischemia/Reperfusion Induced Ventricular Arrhythmias by Decreasing Oxidative Stress in Rats.

BACKGROUND/AIMS: Arctigenin (ATG) has been shown to possess anti-inflammatory, immunemodulatory, anti-viral, anti-microbial, anti-carcinogenic, vasodilatory and anti-platelet aggregation properties. However, the protective role of ATG in prevention of arrhythmias induced by myocardial ischemia/reperfusion is unknown. The aim of this study was to investigate the anti-arrhythmia effect of ATG in an ischemia/reperfusion injured rat heart model and explore the related mechanisms. METHODS: Rats were randomly exposed to sham operation, myocardial ischemia/ reperfusion (MI/R) alone, ATG+ MI/R, pretreated with ATG in low (12.5 mg/kg/day), medium (50 mg/kg/day) and high dose (200 mg/kg/day), respectively. Ventricular arrhythmias were assessed. The activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and the level of malondialdehyde (MDA) in myocardial tissue were determined by chemical analysis. RESULTS: Compared to MI/R, rats pretreated with ATG in doses of 50 mg/kg/day and 200 mg/kg/day showed significantly reduced incidence and duration of ventricular fibrillation, ventricular tachycardia and ventricular ectopic beat (VEB), and decreased the arrhythmia score during the 30-min ischemia. Incidence and duration of ventricular tachycardia, infarction size and arrhythmia scores in these groups were significantly decreased during the 120-min reperfusion. No ventricular fibrillation occurred during the period of reperfusion. Rats pretreated with ATG in doses of 50 mg/kg/day and 200 mg/kg/ day markedly enhanced the activities of antioxidant enzymes SOD and GSH-Px, reduced the level of MDA. No differences were observed between the group pretreated with a low dose of ATG and the sham group. Administration of ATG significantly increased the expression of antioxidant stress protein Nrf2, Trx1 and Nox1. CONCLUSION: Our data suggested that ATG plays anti-arrhythmia role in ischemia/reperfusion injury, which is probably associated with attenuating oxidative stress by Nrf2 signaling pathway.

mRNA expression of IGF-1 and IGF-1R in patients with colorectal adenocarcinoma and type 2 diabetes.

BACKGROUND AND AIMS: Increasing studies show that messenger RNA (mRNA) levels of local IGF-system are overexpressed in cancer tissue of patients with colorectal cancer (CRC). However, the influence of type 2 diabetes (T2DM) on the expression of insulin-like growth factor-1 (IGF-1) and IGF-1 receptor (IGF-1R) mRNA in colorectal cancer tissue and adjacent non-cancerous tissue (ANCT) is unknown. The aim of this study was to assess mRNA expression of IGF-1 and IGF-1R in paired samples of cancer tissue and ANCT between colorectal adenocarcinoma (CA) patients with and without T2DM. METHODS: To quantify the levels of IGF-1 and IGF-1R mRNA in CA, we analyzed the expression of IGF-1 and IGF-1R mRNA levels in paired samples of cancer tissue and ANCT in CA patients with and without T2DM using real-time reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: mRNA levels of IGF-1 and IGF-1R were significantly higher in cancer tissue compared with its ANCT in CA patients with and without T2DM. Compared with the CA group, significantly higher levels of IGF-1 and IGF-1R mRNA were observed in cancer tissue in CA with T2DM group. No significant differences were observed in the role of cancer locations, Dukes stages and diabetes duration on mRNA expression of IGF-1. After adjusting for age, gender and Dukes stages, multivariate analysis indicated IGF-1 mRNA level was a risk factor for prognosis (p <0.05). CONCLUSIONS: Our results support the hypothesis that IGF system plays an important role in CRC. Further larger studies are needed.

[Relationship between colorectal adenocarcinoma with invasive micropapillary carcinoma component and lymph node metastasis].

OBJECTIVE: To investigate the relationship between colorectal adenocarcinoma with invasive micropapillary carcinoma (IMPC) component, lymphovascular invasion, and lymph node metastasis. METHODS: One hundred and thirty one cases of colorectal adenocarcinoma with invasive micropapillary carcinoma component were evaluated by H&E and immunohistochemical staining. The main pathological features, percentage of IMPC component, lymphovascular invasion, and lymph node metastasis were assessed and compared to 296 cases of conventional colorectal adenocarcinoma. RESULTS: The maximum diameter of the tumors of the IMPC group was significantly lower than the conventional group. The degree of differentiation, the lymph node metastatic rate, the average number of metastatic lymph nodes, the number of cases with lymphovascular tumor emboli were significantly higher in the IMPC group (P = 0.000). The rate of distant metastasis at operation was higher in the IMPC group (14.5%) compared to the conventional group (10.8%) even though statistical significance was not achieved (P = 0.278) . In IMPC group, as the IMPC component increased, the rate of lymph node metastasis also showed an increasing trend. The rate of lymph node metastasis were 53.0% (157/296) , 67.7% (42/62) and 85.5% (59/69) " respectively" for conventional adenocarcinoma, adenocarcinoma with ≤ 10% IMPC component and adenocarcinoma with > 10% IMPC component; the difference was statistically significant (P = 0.000). CONCLUSIONS: Compared to conventional colorectal adenocarcinomas, the colorectal carcinomas with IMPC component show a significantly higher rate of lymphovascular invasion, lymph node metastasis and distant metastasis. The percentage of IMPC component in colorectal adenocarcinoma is significantly correlated to the rate of lymph node metastasis. Therefore, presence of IMPC component and degree of tumor differentiation are predicting factors of lymph node metastasis.