Tobacco use among adults in Cambodia: evidence for a tobacco epidemic among women

Objective

To identify the demographic characteristics of current tobacco users in Cambodia, particularly women, and to explore the reasons for current tobacco use in demographic subgroups of the Cambodian population.

Methods

We used a stratified three-stage cluster sample of 13 988 adults aged 18 years and older from all provinces in 2005–2006. Participants completed an interviewer-administered survey that contained items on all forms of tobacco use and on health and lifestyle variables. Multivariable regression analysis was performed to identify demographic predictors of tobacco use.

Findings

Cigarette smoking occurred among 48.0% of men and 3.6% of women. We estimated that 560 482 women (95% confidence interval, CI: 504 783 to 616 180) currently chewed tobacco (typically as a component of betel quid) and that the prevalence more than doubles with each decade of adulthood up to the point that about half of all older women chew tobacco. Both men and women cited the influence of older relatives as their primary reason for starting to use tobacco. About one out of five rural women who used chewing tobacco started their habit for relief from morning sickness. The highest prevalence of chewing tobacco among women was seen among midwives (67.9%) and traditional healers (47.2%). High rates (66.8%) of cigarette and pipe tobacco use occurred among ethnic minorities who represent hill tribes found throughout south-east Asia.

Conclusion

The tobacco epidemic in Cambodia extends far beyond cigarette smoking in men. Tobacco control that focuses only on cigarettes will not address the health burden from smokeless tobacco use in women that may be an integral part of cultural, familial, and traditional medicine practices.     

Metabolism of the active metabolite of quetiapine, N-desalkylquetiapine in vitro

The antipsychotic drug quetiapine has been approved for the treatment of unipolar and bipolar depression. The antidepressant activity is considered to be mediated by the active metabolite N-desalkylquetiapine, which is mainly formed by CYP3A4. Little is known about the subsequent elimination of this metabolite. Therefore, this study investigated the possible involvement of cytochrome P450 (P450) enzymes in the metabolism of N-desalkylquetiapine. Screening for and interpretation of metabolites were performed by incubating N-desalkylquetiapine in human liver microsomes (HLM) followed by liquid chromatography-tandem mass spectrometry. The possible involvement of P450 enzymes in N-desalkylquetiapine metabolism was evaluated by coincubation of selective P450 inhibitors in HLM and subsequent experiments with recombinant human P450 enzymes. In HLM experiments, three chromatographic peaks were interpreted as possible metabolites of N-desalkylquetiapine, namely, N-desalkylquetiapine sulfoxide, 7-hydroxy-N-desalkylquetiapine, and an unrecognized metabolite (denoted M3). Inhibition of CYP2D6 (by quinidine) reduced formation of 7-hydroxy-N-desalkylquetiapine by 81%, whereas the CYP3A4 inhibitor ketoconazole inhibited formation of N-desalkylquetiapine sulfoxide and M3 by 65 and 34%, respectively. Inhibitors of CYP1A2, CYP2C9, and CYP2C19 showed only limited changes in metabolite formation. In recombinant systems, 7-hydroxy-N-desalkylquetiapine was exclusively formed by CYP2D6, whereas N-desalkylquetiapine sulfoxide and M3 were formed by both CYP3A4 and CYP2D6. Overall, intrinsic clearance of N-desalkylquetiapine was 12-fold higher by recombinant CYP2D6 relative to CYP3A4. In conclusion, N-desalkylquetiapine is metabolized by both CYP2D6 and CYP3A4 in vitro with preference for the former enzyme. The pharmacologically active metabolite, 7-hydroxy-N-desalkylquetiapine, was exclusively formed by CYP2D6, whereas the two other metabolites were mainly formed by CYP3A4.     

Bioavailability of cobalt and silver nanoparticles to the earthworm Eisenia fetida

Due to difficulties in tracing engineered nanoparticles (ENPs) in complex media, there are few data on the exposure of soil biota to ENPs. This study used neutron activated cobalt (Co NPs) and silver (Ag NPs) nanoparticles, as well as soluble cobalt and silver salts, to assess the uptake, excretion and biodistribution in the earthworm Eisenia fetida. Concentrations of cobalt in worms after four weeks exposure reached 88% and 69% of the Co ions and Co NPs concentrations in food, respectively, while corresponding values for Ag ions and Ag NPs were 2.3% and 0.4%. Both Ag ions and Ag NPs in earthworms were excreted rapidly, while only 32% of the cobalt accumulated from Co ions and Co NPs were excreted within four months. High accumulation of cobalt was found in blood and in the digestive tract. Metal characterization in the exposure medium was assessed by sequential extraction and ultrafiltration. The Co NPs showed significant dissolution and release of ions, while Ag ions and particularly Ag NPs were more inert.     

Teenagers’ Explanations of Bullying

The aim of the present study was to explore how teenagers explain why bullying takes place at school, and whether there were any differences in explaining bullying due to gender and prior bullying experiences. One hundred and seventy-six Swedish students in Grade 9 responded to a questionnaire. Mixed methods (qualitative and quantitative methods) were used to analyze data. The grounded theory analysis generated five main categories and 26 sub categories regarding accounts of bullying causes. Results indicated that youth tended to explain bullying in terms of individualistic reasons (bully attributing and victim attributing) than in terms of peer group, school setting, or human nature/society reasons. Girls were more likely to attribute bullying causes to the bully and much less to the victim, compared to boys. Moreover, youth classified as bullies were more likely to attribute the reason for bullying to the victim and much less to the bully, compared to victims, bystanders, and victims/bullies.     

The association between fatal coronary heart disease and ambient particulate air pollution: Are females at greater risk?

The purpose of this study was to assess the effect of long-term ambient particulate matter (PM) on risk of fatal coronary heart disease (CHD). A cohort of 3,239 nonsmoking, non-Hispanic white adults was followed for 22 years. Monthly concentrations of ambient air pollutants were obtained from monitoring stations [PM < 10 microm in aerodynamic diameter (PM10), ozone, sulfur dioxide, nitrogen dioxide] or airport visibility data [PM < 2.5 microm in aerodynamic diameter (PM2.5)] and interpolated to ZIP code centroids of work and residence locations. All participants had completed a detailed lifestyle questionnaire at baseline (1976), and follow-up information on environmental tobacco smoke and other personal sources of air pollution were available from four subsequent questionnaires from 1977 through 2000. Persons with prevalent CHD, stroke, or diabetes at baseline (1976) were excluded, and analyses were controlled for a number of potential confounders, including lifestyle. In females, the relative risk (RR) for fatal CHD with each 10-microg/m3 increase in PM2.5 was 1.42 [95% confidence interval (CI), 1.06-1.90] in the single-pollutant model and 2.00 (95% CI, 1.51-2.64) in the two-pollutant model with O3. Corresponding RRs for a 10-microg/m3 increase in PM(10-2.5) and PM10 were 1.62 and 1.45, respectively, in all females and 1.85 and 1.52 in postmenopausal females. No associations were found in males. A positive association with fatal CHD was found with all three PM fractions in females but not in males. The risk estimates were strengthened when adjusting for gaseous pollutants, especially O3, and were highest for PM2.5. These findings could have great implications for policy regulations.     

Early sexual maturation,central adiposity and subsequent overweight in late adolescence. A four-year follow-up of 1605 adolescent Norwegian boys and girls: the Young HUNT study

Background  

Early sexual maturation has been associated with overweight that may persist after the completion of biological growth and development. We have prospectively examined the influence of early sexual maturation on subsequent overweight in late adolescence and assessed if this association was modified by central adiposity in early adolescence.     

Changes in BMI-distribution from 1966–69 to 1995–97 in adolescents. The Young-HUNT study,Norway

Background  

The aim of this study was to explore changes in the BMI-distribution over time among Norwegian adolescents.