Racial/Ethnic Differences in Associations of Non-cigarette Tobacco Product Use With Subsequent Initiation of Cigarettes in US Youths.

INTRODUCTION: Understanding which non-cigarette tobacco products precede smoking in youth across different racial/ethnic groups can inform policies that consider tobacco-related health disparities. METHODS: We used nationally representative, longitudinal data from the Population Assessment of Tobacco and Health Study waves 1-4. The sample was a dynamic cohort of cigarette-naïve youth aged 12-17 years. Mixed-effects models were used to assess non-cigarette product (e-cigarette, cigar product, or other product) use with cigarette use over 1-year intervals. RESULTS: Of the 28 788 observations pooled across waves 1-4, respondents were 48.7% non-Hispanic white, 13.9% non-Hispanic black, and 23.1% Hispanic. Odds of cigarette initiation over 1-year follow-up were higher among youth with prior use of e-cigarettes (odds ratio [OR], 2.76; 95% confidence interval [CI], 2.21-3.45), cigars (OR, 2.00; 95% CI, 1.42-2.80), or other products (OR, 1.66; 95% CI, 1.28-2.14) compared to never users. At the population level, 20.6% of cigarette initiation was attributable to e-cigarette use among white youth and 21.6% among Hispanic youth, while only 3.5% of cigarette initiation was attributable to e-cigarette use among black youth. In contrast, 9.1% of cigarette initiation for black youth was attributable to cigar use compared to only 3.9% for both white and Hispanic youth. CONCLUSIONS: Prior use of e-cigarettes, cigars, and other non-cigarette products were all associated with subsequent cigarette initiation. However, white and Hispanic youth were more likely to initiate cigarettes through e-cigarette use (vs. cigar or other product use), while black youth were more likely to initiate cigarettes through cigar use (vs. e-cigarette or other product use). IMPLICATIONS: Our findings suggest that previous studies on effects of non-cigarette tobacco products may overlook the critical role of cigar products as a pathway into cigarette smoking among US youth, particularly black youth. While our data support the importance of e-cigarette use as a pathway into smoking, regulatory actions aimed at addressing youth e-cigarette use alone may contribute to disparities in black versus white tobacco use and further exacerbate inequities in tobacco-related disease. Thus, contemporary policy development and discourse about the effects of non-cigarette tobacco products on cigarette initiation should consider cigar and other non-cigarette products as well as e-cigarettes.

Gene expression profiling in porcine maternal infanticide: a model for puerperal psychosis.

The etiology of mental disorders remains largely unclear. Complex interactions between genetic and environmental factors are key to the development of such disorders. Puerperal psychosis is the most extreme form of postnatal mood disorder in women. Similarly, parturition in the pig can trigger extreme behavioral disturbances, including maternal infanticide. In this study, we have used a targeted cDNA microarray approach using the pig as a model to understand the genes and genetic pathways that are involved in these processes. Two subtracted cDNA libraries from porcine hypothalamus were constructed, which were enriched for genes that were over-expressed and under-expressed in the aberrant behavioral phenotype, compared to the matched control. In addition to this, a normalized library was constructed from hypothalamus and pituitary samples taken from pigs in a variety of reproductive states. The libraries were partially sequenced and combined represented approximately 5,159 different genes. Microarray analysis determined differences in gene expression between hypothalamus samples from nine matched pairs of infanticidal versus control animals, using a common reference design. Microarray analysis of variance (MAANOVA) identified 52 clones as being differentially expressed (P

Porcine maternal infanticide as a model for puerperal psychosis.

Childbirth is a period of substantial rapid biological and psychological change and a wide range of psychotic disorders can occur ranging from mild 'baby blues' to severe episodes of psychotic illnesses. Puerperal psychosis is the most extreme form of postnatal psychosis, occurring in 1 in 1,000 births. In this study, we have used the pig as an animal model for human postnatal psychiatric illness. Our aim was to identify quantitative trait loci (QTL) associated with maternal (infanticide) sow aggression. This is defined by sows attacking and killing their own newborn offspring, within 24 hr of birth. An affected sib pair whole genome linkage analysis was carried out with 80 microsatellite markers covering the 18 porcine autosomes and the X chromosome, with the aim of identifying chromosomal regions responsible for this abnormal behavior. Analysis was carried out using the non-parametric linkage test of Whittemore and Halpern, as implemented in the Merlin software. The results identified 4 QTL mapping on Sus scrofa chromosomes 2 (SSC2), 10 (SSC10), and X (SSCX). The peak regions of these QTL are syntenic to HSA 5q14.3-15, 1q32, Xpter-Xp2.1, and Xq2.4-Xqter, respectively. Several potential candidate genes lie in these regions in addition to relevant abnormal behavioral QTL, found in humans and rodents.