Publications

OBJECTIVE

To explore and understand key cultural contexts of tobacco use among South Asian communities in the USA.

DESIGN

Focus groups, with homogeneous compositions of gender, generational status and length of time in the USA, were conducted in two distinct South Asian ethnic enclaves. Focus group findings were triangulated with observational data regarding the availability of culturally specific tobacco from commercial ethnic outlets and cultural events.

SUBJECTS

Respondents included 88 men and women of South Asian descent, aged 18-65 years, immigrant and native born, representing diversity of religion, socioeconomic status and region of origin, with the use of at least one culturally specific tobacco product in previous 24 months.

RESULTS

A large number of culturally specific products were commonly used by community members. Knowledge of product-specific health risks was lacking or inaccurate. Many culturally specific tobacco products were considered to have beneficial properties. South Asian tobacco items were used to preserve cultural traditions and express ethnic identity in a new dominant culture. The social and cultural values ascribed to use helped distinguish community members from mainstream society and from other minority populations.

CONCLUSIONS

Many cultural factors govern tobacco use among diverse global populations. Especially for migrants with a common regional origin, the role of ethnic identity may strongly influence culturally specific tobacco patterns. Qualitative inquiry helps elucidate such culturally framed behaviour in culturally diverse populations. These cultural contexts should be integrated into research and practice. Understanding multidimensional factors influencing non-traditional tobacco use is essential to ensure that comprehensive tobacco control strategies address tobacco-related disparities.

HIV-infected individuals are at increased risk for cardiovascular disease (CVD) and lipodystrophy, but the relationship between regional adipose tissue (AT) depots and CVD risk is not well described. We determined regional AT volumes and CVD risk in an analysis of 586 HIV-infected and 280 control FRAM study subjects using whole-body magnetic resonance imaging (MRI) and the Framingham Risk Score (FRS). Median FRS and FRS >10% were higher in HIV than control men (4.7% vs. 3.7%, p=0.0002; 16% vs. 4%, p<0.0001). HIV and control women had similarly low FRS (1.1% vs. 1.2%, p=0.91). In controls, total AT and all regional AT depots showed strong positive correlations with FRS (p<0.001) in men and weaker positive correlations in women. Greater visceral AT (VAT) and lower leg subcutaneous AT (SAT) volumes were associated with elevated FRS in HIV subjects with a trend for upper trunk SAT. Controls in the lowest quartile of leg SAT had the lowest FRS (1.5%), whereas HIV with similarly low leg SAT had the highest FRS (4.0%, p<0.001 vs. controls). Increased VAT is associated with CVD risk, but the risk is higher in HIV-infected individuals relative to controls at every level of VAT. Peripheral lipoatrophy (as measured by leg SAT) is associated with striking increased CVD risk in HIV-infected patients even after controlling for VAT, whereas low leg SAT is associated with low CVD risk in controls.

Laminins and their integrin receptors are implicated in epithelial cell differentiation and progenitor cell maintenance. We report here that a previously unrecognized subpopulation of mouse alveolar epithelial cells (AECs) expressing the laminin receptor α6β4, but little or no pro-surfactant C (pro-SPC), is endowed with regenerative potential. Ex vivo, this subpopulation expanded clonally as progenitors but also differentiated toward mature cell types. Integrin β4 itself was not required for AEC proliferation or differentiation. An in vivo embryonic lung organoid assay, which we believe to be novel, was used to show that purified β4+ adult AECs admixed with E14.5 lung single-cell suspensions and implanted under kidney capsules self-organized into distinct Clara cell 10-kDa secretory protein (CC10+) airway-like and SPC+ saccular structures within 6 days. Using a bleomycin model of lung injury and an SPC-driven inducible cre to fate-map AECs, we found the majority of type II AECs in fibrotic areas were not derived from preexisting type II AECs, demonstrating that SPC- progenitor cells replenished type II AECs during repair. Our findings support the idea that there is a stable AEC progenitor population in the adult lung, provide in vivo evidence of AEC progenitor cell differentiation after parenchymal injury, and identify a strong candidate progenitor cell for maintenance of type II AECs during lung repair.

RATIONALE

Gastroesophageal reflux (GER) is highly prevalent in patients with idiopathic pulmonary fibrosis (IPF). Chronic microaspiration secondary to GER may play a role in the pathogenesis and natural history of IPF.

OBJECTIVES

To investigate the relationship between GER-related variables and survival time in patients with IPF.

METHODS

Regression analysis was used to investigate the relationship between GER-related variables and survival time in a retrospectively identified cohort of patients with well-characterized IPF from two academic medical centers.

MEASUREMENTS AND MAIN RESULTS

Two hundred four patients were identified for inclusion. GER-related variables were common in this cohort: reported symptoms of GER (34%), a history of GER disease (45%), reported use of GER medications (47%), and Nissen fundoplication (5%). These GER-related variables were significantly associated with longer survival time on unadjusted analysis. After adjustment, the use of GER medications was an independent predictor of longer survival time. In addition, the use of gastroesophageal reflux medications was associated with a lower radiologic fibrosis score. These findings were present regardless of center.

CONCLUSIONS

The reported use of GER medications is associated with decreased radiologic fibrosis and is an independent predictor of longer survival time in patients with IPF. These findings further support the hypothesis that GER and chronic microaspiration may play important roles in the pathobiology of IPF.