The traditional Chinese medicines (TCMs) are essential components of alternative medicines. Many TCMs are known to alter the expression of hepatic drug-metabolizing enzymes and transporters. The molecular mechanism by which TCMs and/or their constituents regulate enzyme and transporter expression, however, has remained largely unknown. In this report, we show that two TCMs, Wu Wei Zi (Schisandra chinensis Baill) and Gan Cao (Glycyrrhiza uralensis Fisch), and their selected constituents activate the xenobiotic orphan nuclear receptor pregnane X receptor (PXR). Treatment with TCM extracts and the Schisandrol and Schisandrin constituents of Wu Wei Zi induced the expression of drug-metabolizing enzymes and transporters in reporter gene assays and in primary hepatocyte cultures. The affected enzymes and transporters include CYP3A and 2C isozymes and the multidrug resistance-associated protein 2. In transient transfection and reporter gene assays, the Schisandrin constituents of Wu Wei Zi had an estimated EC 50 of 2 and 1.25 M on hPXR and mPXR, respectively. Interestingly, mutations that were intended to alter the pore of the ligand-binding cavity of PXR had species-specific effects on the activities of the individual Schisandrols and Schisandrins. In rats, the administration of Wu Wei Zi and Gan Cao increased the metabolism of the coadministered warfarin, reinforcing concerns involving the safe use of herbal medicines and other nutraceuticals to avoid PXR-mediated drug-drug interactions. Meanwhile, the activation of PXR and induction of detoxifying enzymes provide a molecular mechanism for the hepatoprotective effects of certain TCMs.

Important behavioral sources of risk for cancer have been identified and programs to reduce this risk have been initiated. The most heavily studied behavioral risk is tobacco use, but considerable attention has also gone to prevention of skin cancer by modifying sun exposure. Research has shown a strong link between sun exposure and skin cancer, and opportunities to prevent this cancer by changing behavior should be effective. Unlike unmodifiable sources of risk, sun exposure should be modifiable through behavioral intervention. This review considers research in this expanding area, concentrating on predictors of sun protective behaviors, modification of sun exposure, and surveillance for early signs of cancer. The elements of behavior change programs that contribute to successful intervention as well as barriers to successful behavior change and future directions for this effort are considered.

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This study examined the relationship between pre-migration trauma and HIV-risk behavior in refugees from sub-Saharan Africa. The sample comprised 122 persons who had emigrated from sub-Saharan Africa and were currently residing in Sweden. Qualitative methods including individual interviews, focus groups, and interviews with key informants addressed questions regarding trauma experience and HIV-risk behavior. A history of pre-migration trauma was found to be associated with HIV-risk behavior. According to the participants, symptoms associated with post-traumatic stress disorder, depression, adjustment disorder, and substance use mediated the relationship between pre-migration trauma and sexual risk behavior. In contrast, a minority of the participants who reported pre-migration trauma but not psychological sequelae, or experienced post-traumatic growth, reported safer sexual practices. It appears that for some individuals, pre-migration trauma resulted in psychiatric sequelae, which may increase an individual's risk to be infected with HIV. Interventions targeted at individuals at increased risk (i.e. pre-migration trauma with unresolved psychiatric symptomatology) may facilitate the prevention of HIV and other sexually transmitted diseases in this population. Integration of multiple psychosocial and health issues is recommended for comprehensive treatment and prevention programs.

This study examined the relationship between pre-migration trauma and HIV-risk behavior in refugees from sub-Saharan Africa. The sample comprised 122 persons who had emigrated from sub-Saharan Africa and were currently residing in Sweden. Qualitative methods including individual interviews, focus groups, and interviews with key informants addressed questions regarding trauma experience and HIV-risk behavior. A history of pre-migration trauma was found to be associated with HIV-risk behavior. According to the participants, symptoms associated with posttraumatic stress disorder, depression, adjustment disorder, and substance use mediated the relationship between pre-migration trauma and sexual risk behavior. In contrast, a minority of the participants who reported