Faculty Bibliography

Particulate matter (PM) varies in chemical composition and mass concentration based on location, source, and particle size. This study sought to evaluate the in vitro and in vivo toxicity of coarse (PM10-2.5) and fine (PM25) PM samples collected at 5 diverse sites within California. Coarse and fine PM samples were collected simultaneously at 2 rural and 3 urban sites within California during the summer. A human pulmonary microvascular endothelial cell line (HPMEC-ST1.6R) was exposed to PM suspensions (50 mug/mL) and analyzed for reactive oxygen species (ROS) after 5 hours of treatment. In addition, FVB/N mice were exposed by oropharyngeal aspiration to 50 mug PM, and lavage fluid was collected 24 hrs post-exposure and analyzed for total protein and %PMNs. Correlations between trace metal concentrations, endotoxin, and biological endpoints were calculated, and the effect of particle size range, locale (urban vs. rural), and location was determined. Absolute principal factor analysis was used to identify pollution sources of PM from elemental tracers of those sources. Ambient PM elicited an ROS and pro-inflammatory-related response in the cell and mouse models, respectively. These responses were dependent on particle size, locale, and location. Trace elements associated with soil and traffic markers were most strongly linked to the adverse effects in vitro and in vivo. Particle size, location, source, and composition of PM collected at 5 locations in California affected the ROS response in human pulmonary endothelial cells and the inflammatory response in mice.

BACKGROUND: The Affordable Care Act has added millions of new Medicaid enrollees to the health care system. These patients account for a large proportion of emergency department (ED) utilization. OBJECTIVE: Our aim was to characterize this population and their ED use at a national level. METHODS: We used the 2010 National Hospital Ambulatory Medical Care Survey (NHAMCS) to describe demographics and clinical characteristics of nonelderly adults (>/=18 years old and /=4 ED visits/year and business hours as 8 am to 5 pm. We used descriptive statistics to describe the epidemiology of Medicaid-covered ED visits. RESULTS: NHAMCS included 21,800 ED visits by nonelderly adults in 2010, of which 5,659 (24.09%) were covered by Medicaid insurance. Most ED visits covered by Medicaid were made by patients who are young (25 and 44 years old) and female (67.95%; 95% confidence interval [CI] 66.00-69.89). A large proportion of the ED visits covered by Medicaid were revisits within 72 h (14.66%; 95% CI 9.13-20.19) and from frequent ED users (32.32%; 95% CI 24.29-40.35). Almost half of all ED visits covered by Medicaid occurred during business hours (45.44%; 95% CI 43.45-47.43). CONCLUSIONS: The vast majority of Medicaid enrollees who used the ED were young females, with a large proportion of visits occurring during business hours. Almost one-third of all visits were from frequent ED users.

Genetic polymorphisms in vitamin D metabolism and signaling genes have been inconsistently associated with risk of breast cancer, though few studies have examined SNPs in vitamin D-related genes other than the vitamin D receptor (VDR) gene and particularly have not examined the association with the retinoid X receptor alpha (RXRA) gene which may be a key vitamin D pathway gene. We conducted a nested case-control study of 734 cases and 1435 individually matched controls from a population-based prospective cohort study, the Northern Sweden Mammary Screening Cohort. Tag and functional SNPs were genotyped for the VDR, cytochrome p450 24A1 (CYP24A1), and RXRA genes. We also genotyped specific SNPs in four other genes related to vitamin D metabolism and signaling (GC/VDBP, CYP2R1, DHCR7, and CYP27B1). SNPs in the CYP2R1, DHCR7, and VDBP gene regions that were associated with circulating 25(OH)D concentration in GWAS were also associated with plasma 25(OH)D in our study (p-trend <0.005). After taking into account the false discovery rate, these SNPs were not significantly associated with breast cancer risk, nor were any of the other SNPs or haplotypes in VDR, RXRA, and CYP24A1. We observed no statistically significant associations between polymorphisms or haplotypes in key vitamin D-related genes and risk of breast cancer. These results, combined with the observation in this cohort and most other prospective studies of no association of circulating 25(OH)D with breast cancer risk, do not support an association between vitamin D and breast cancer risk.

INTRODUCTION: Smoking prevalence is higher among sexual minorities compared to their heterosexual peers. However, very little is known about potential racial differences in smoking among sexual minority populations. We examined differences by race in smoking status among a robust sample of sexual minorities. METHODS: We used data from the 2010 Social Justice Sexuality project, a large national convenience sample of sexual minority adults that oversampled individuals from racial minority groups. Log-Poisson multivariable regression models were employed to determine the risk of current smoking among sexual minority individuals by race after controlling for socio-demographic characteristics. RESULTS: Among smokers, 22.35% identified as White, 26.98% identified as Black, 19.38% identified as Latino/Hispanic, 5.58% identified as Asian American, and 25.67% were other/multiracial. In fully adjusted gender stratified models, Black men (adjusted risk ratio [aRR] = 0.61, 95% confidence interval [CI] = 0.50, 0.75) and Asian American men (aRR = 0.61, 95% CI = 0.50, 0.75) were at lower risk of smoking compared to White men. Black women were the only to remain statistically significant for decreased risk of smoking in fully adjusted gender stratified models (aRR = 0.78, 95 % CI = 0.65, 0.95). CONCLUSIONS: Among sexual minorities, Black and Asian American individuals consistently were at decreased risk of current smoking compared to their White peers. Future research should seek to understand the mechanisms that contribute to decreased smoking status among racial sexual minorities.

BACKGROUND: Vietnam has a smoking prevalence that is the second highest among Southeast Asian countries (SEACs). According to the World Health Organization (WHO), most reductions in mortality from tobacco use in the near future will be achieved through helping current users quit. Yet, largely due to a lack of research on strategies for implementing WHO-endorsed treatment guidelines in primary care settings, services to treat tobacco dependence are not readily available to smokers in low middle-income countries (LMICs) like Vietnam. The objective of this study is to conduct a cluster randomized controlled trial that compares the effectiveness of two system-level strategies for implementing evidence-based guidelines for the treatment of tobacco use in 26 public community health centers (CHCs) in Vietnam. METHODS/DESIGN: The current study will use a cluster-randomized design and multiple data sources (patient exit interviews, provider and village health worker (VHW) surveys, and semi-structured provider/VHW interviews) to study the process of adapting and implementing clinical practice guidelines in Vietnam and theory-driven mechanisms hypothesized to explain the comparative effectiveness of the two strategies for implementation. CHCs will be randomly assigned to either of the following: (1) training plus clinical reminder system (TC) or (2) TC + referral to a VHW (TCR) for three in person counseling sessions. The primary outcome is provider adherence to tobacco use treatment guidelines. The secondary outcome is 6-month biochemically verified smoking abstinence. DISCUSSION: The proposed implementation strategies draw on evidence-based approaches and a growing literature that supports the effectiveness of integrating community health workers as members of the health care team to improve access to preventive services. We hypothesize that the value of these implementation strategies is additive and that incorporating a referral resource that allows providers to delegate the task of offering counseling (TCR) will be superior to TC alone in improving delivery of cessation assistance to smokers. The findings of this research have potential to guide large-scale adoption of promising strategies for implementing and disseminating tobacco use treatment guidelines throughout the public health system in Vietnam and will serve as a model for similar action in other LMICs. TRIAL REGISTRATION: NCT01967654.

Danil V Makarov speaks to Gemma Westcott, Commissioning Editor: Danil V Makarov is an Assistant Professor and Director of Surgical Research in the Department of Urology at NYU Langone Medical Center (NY, USA). In addition, he is an Assistant Professor in the Department of Population Health. His clinical areas of expertise include prostate cancer, benign prostatic hyperplasia, erectile dysfunction, kidney cancer, urinary tract infections, genitourinary neoplasm, elevated prostate-specific antigen and testicular cancer. In addition, his research interests are in the areas of prostate cancer, health policy and quality of care. An alumnus of the Johns Hopkins University School of Medicine (MD, USA), he completed his residency in urology at Johns Hopkins Hospital and a research fellowship at Yale University School of Medicine (CT, USA).

Concussion may lead to subtle changes in brain function, and tests involving the visual system probe higher cortical functioning and increase our sensitivity in detecting these changes. Concussions are acutely and sometimes more persistently associated with abnormalities in balance, cognition, and vision. The visual system involves roughly half of the brain's circuits, including many regions susceptible to head impacts. After a concussion, the neuro-ophthalmologic exam commonly detects abnormalities in convergence, accommodation, the vestibulo-ocular reflex, ocular muscle balance, saccades, and pursuit. The King-Devick (K-D) test is a visual performance measure that may increase the sensitivity of detecting concussions on the sideline when used in combination with tests of cognition and balance that are part of the Sports Concussion Assessment Tool (3rd ed.; SCAT3). Portable eye movement trackers and pupillometry may in the future improve our neuro-ophthalmic assessment after concussions. Combining visual tasks with neuroimaging and neurophysiology has allowed subtle changes to be detected, may refine our ability to make appropriate return-to-play decisions, and could potentially determine susceptibility to long-term sequelae of concussion.

Optical coherence tomography (OCT) is a relatively new technology that is now routinely and very widely used by ophthalmologists for structural documentation of the optic nerve and retina. In neuro-ophthalmology and neurology, the value of OCT is ever expanding; its role in an increasing number of conditions is being reported in parallel with the advances of the technology. Currently, as a clinical tool, OCT is particularly useful for the structural measurement of peripapillary retinal nerve fiber layer thickness, optic nerve head volumetric analysis, and macular anatomy. Optic neuropathies of varied etiology (particularly from multiple sclerosis) may be the most common clinical indications for neurologists to obtain OCT imaging. Documentation and follow-up of disc edema of varied etiology (papilledema and idiopathic intracranial hypertension), discriminating true disc swelling from pseudopapilledema, and differentiating optic neuropathy from maculopathy are some other examples from clinical practice.

OBJECTIVE: Pediatricians report many barriers to caring for children with mental health (MH) problems. The American Academy of Pediatrics (AAP) has focused attention on MH problems, but the impact on perceived barriers is unknown. We examined whether perceived barriers and their correlates changed from 2004 to 2013. METHODS: In 2004, 832 (52%) of 1600 and in 2013, 594 (36.7%) of 1617 of randomly selected AAP members surveyed responded to periodic surveys, answering questions about sociodemographics, practice characteristics, and 7 barriers to identifying, treating/managing, and referring child/adolescent MH problems. To reduce nonresponse bias, weighted descriptive and logistic regression analyses were conducted. RESULTS: Lack of training in treatment of child MH problems ( approximately 66%) and lack of confidence treating children with counseling ( approximately 60%) did not differ across surveys. Five barriers (lack of training in identifying MH problems, lack of confidence diagnosing, lack of confidence treating with medications, inadequate reimbursement, and lack of time) were less frequently endorsed in 2013 (all P < .01), although lack of time was still endorsed by 70% in 2013. In 2004, 34% of pediatricians endorsed 6 or 7 barriers compared to 26% in 2013 (P < .005). Practicing general pediatrics exclusively was associated with endorsing 6 or 7 barriers in both years (P < .001). CONCLUSIONS: Although fewer barriers were endorsed in 2013, most pediatricians believe that they have inadequate training in treating child MH problems, a lack of confidence to counsel children, and limited time for these problems. These findings suggest significant barriers still exist, highlighting the need for improved developmental and behavioral pediatrics training.