Associations among genetic susceptibility, DNA damage, and pregnancy outcomes of expectant mothers exposed to environmental tobacco smoke.

This study determined the effects of environmental tobacco smoke (ETS) on fetal growth by measuring neonatal birth outcomes and the extent of maternal DNA damage, and investigating the relationships among gene polymorphisms, genotoxicity, and pregnancy outcomes of expectant mothers who had exposed to tobacco smoke. This prospective study enrolled 685 pregnant women who completed an initial questionnaire at three central Taiwan hospitals between 2003 and 2004. Genotype analyses of CYP1A1, GSTT1, GSTM1, and NAT2 were performed from 421 women. A total of 398 women completed the follow-up analysis and successfully delivered a live single baby (n=384). Comet assay was performed for 18 smokers, 143 ETS-exposed subjects and 130 non-smokers to measure DNA damage. Analytical findings indicated that the levels of DNA damage among smokers and ETS-exposed subjects were significantly higher than that of non-smokers. DNA damage score in the ETS-exposed group was 84.3+/-44.3 and 63.5+/35.0 [corrected] for the nonsmoking group (p<0.001). Risk of DNA damage (DNA strand breakage, sister chromatid exchange, cell transformation and escalation of cytotoxicity) for subjects exposed to ETS was 7.49 times (adjusted odds ratio; 95% CI, 1.27-44.20) [corrected] greater than that of non-exposed to tobacco smoke at home. Average birth weight of neonates born to subjects with extremely serious DNA damage (within the 90th percentile, DNA damage score >or =129.5) was 141 g lighter than that of those with DNA damage score <129.5 (p=0.068) [corrected] The degree of DNA lesion was not related to metabolic polymorphic genes. The results of this study suggest that comet assay are reliable biomarkers for monitoring pregnant women exposed to tobacco smoke and indicate fetal growth effects from environmental exposure to tobacco smoke.

The role of community mental health nurses caring for people with schizophrenia in Taiwan: a substantive grounded theory.

AIM AND OBJECTIVES: The aim was to develop a practice theory that can be used to guide the direction of community nursing practice to help clients with schizophrenia and those who care for them. DESIGN: Substantive grounded theory was developed through use of grounded theory method of Strauss and Corbin. METHODS: Two groups of participants in Taiwan were selected using theoretical sampling: one group consisted of community mental health nurses and the other group was clients with schizophrenia and those who cared for them. The number of participants in each group was determined by theoretical saturation. Semi-structured one-to-one in-depth interviews and unstructured non-participant observation were utilized for data collection. Data analysis involved three stages: open, axial and selective coding. During the process of coding and analysis, both inductive and deductive thinking were utilized and the constant comparative analysis process continued until data saturation occurred. To establish trustworthiness, the four criteria of credibility, transferability, dependability and confirmability were followed along with field trial, audit trial, member check and peer debriefing for reliability and validity. RESULTS: A substantive grounded theory, the role of community mental health nurses caring for people with schizophrenia in Taiwan, was developed through utilization of grounded theory method of Strauss and Corbin. CONCLUSION: In this paper, results and discussion focus on causal conditions, context, intervening conditions, consequences and phenomenon. RELEVANCE TO CLINICAL PRACTICE: The theory is the first to contribute knowledge about the field of mental health home visiting services in Taiwan to provide guidance for the delivery of quality care to assist people in the community with schizophrenia and their carers.

Prenatal smoking exposure and neonatal DNA damage in relation to birth outcomes.

This study investigated whether mothers with prenatal environmental tobacco smoke (ETS) exposure increased the newborn genetic damage and adverse birth outcomes. Study participants were women receiving prenatal care at three hospitals in Central Taiwan and their newborns. Participants were divided into two groups (nonsmokers and ETS-exposed non-smokers) based on maternal ETS-exposed status. Comet assay were performed for cord blood samples. Infants born to mothers with prenatal ETS exposure had the highest mean cord blood DNA damage score (69.7 +/- 42.3) and poorer birth outcomes. No negative fetal growth effects appeared among newborns with low DNA damage levels. Among newborns with high DNA damage levels (comet scores >50), those born to prenatal ETS exposure had an average reduction of 252.7 g in birth weight, 1.10 cm shorter in length and a 0.92-cm decrease in head circumference, compared to newborns with no smoking exposure. This study shows that the DNA damage scores can be used as an effect-modifier on the relationships between ETS exposure and adverse birth outcome. The association appears more apparent for the ETS exposure in relation with more severe DNA damage.