It's not all about price: factors associated with roll-your-own tobacco use among young people - a qualitative study.

BACKGROUND: Smoking prevalence in Ireland is falling in all age groups, but the prevalence of roll-your-own (RYO) tobacco use is rising among young people. This qualitative study aims to explore and understand the factors associated with young people's use of RYO products. METHODS: Semi-structured individual and focus group interviews were conducted with young people aged 16-22 years. Participants were recruited from a higher education institution and youth organisations working with early school leavers across Dublin. In total, there were 62 participants in the study, consisting of 22 individual interviews and eight focus group interviews with 40 participants. Categoric and thematic data analysis was used to generate the findings. RESULTS: We identified two broad themes, incentivising and disincentivising factors. The lower cost of RYO products compared to pre-manufactured cigarettes was the most important incentive for users. However, other product characteristics, such as the artisanal factors associated with RYO products were also found. Social and environmental influences were apparent, in which certain groups and environments facilitated and normalised RYO practices. Amenities and facilities often provided smokers with normalised spaces which could be dedicated to the enactment of rolling practices and to the creation and maintenance of social bonds with other users. Disincentives included negative features related to the product itself, adverse health effects, and the effects of tobacco denormalisation. CONCLUSIONS: While the lower cost of RYO products is very important for young smokers, other product characteristics and influences also incentivise and disincentivise use. A more comprehensive understanding of the multi-dimensional appeal of these products will assist policymakers to target strategies to reduce the attractiveness to young smokers of these products.

CellVue Claret, a new far-red dye, facilitates polychromatic assessment of immune cell proliferation.

Flow cytometric analyses of immune cell proliferation, differentiation, and function are limited by the number of different fluorochromes that can be resolved simultaneously. Additional colors to expand functional analytic capability will facilitate higher dimensional analyses of heterogeneous cell populations by basic and clinical scientists. Our aim in these studies was to evaluate CellVue Claret, a fluorescent, far-red emitting, membrane intercalating dye (excitation maximum: 655 nm, emission maximum 677 nm), as an alternative and/or complementary probe to PKH26 and CFSE(1) for polychromatic studies of immune cell proliferation and function. Using a BD FACSCalibur and human peripheral blood mononuclear cells (PBMCs) from 8 different donors (2 donors studied twice), we compared CellVue Claret with the two most commonly used visible-emitting proliferation dyes, PKH26 and CFSE, in terms of: (1) compatibility with 7-Amino-actinomycin D (7-AAD) as a viability marker; (2) effect of dye labeling on lymphocyte viability; and (3) the proliferative response of CD3+ T lymphocytes from 0-96 hours as assessed by dilution of each of the 3 cell tracking dyes in cultures stimulated with anti-CD3 plus IL-2. Post-labeling recoveries and viabilities were similar for all 3 dyes, with modestly higher initial staining intensities and coefficients of variation for CellVue Claret than for CFSE or PKH26. Lymphocyte viabilities in stimulated or unstimulated cultures were also unaffected by choice of dye. Proliferative responses of viable CD3+ lymphocytes were comparable for all three dyes, whether results were reported as Proliferative Fraction (percent of cells that had divided one or more times) or as Precursor Frequency (percent of parent population that had gone on to proliferate in response to anti-CD3 plus IL-2). In summary, T cell proliferation analysis using CellVue Claret gives results equivalent to those obtained with PKH26 or CFSE, expanding the choice of proliferation dyes suitable for use in high dimensional polychromatic studies on flow cytometers with far red (633 nm-658 nm) excitation capabilities.