Health disparities among young adult sexual minorities in the U.S.

Background: Emerging research suggests that young adult sexual minorities (identifying as lesbian, gay, or bisexual or engaging in same-sex attractions or behaviors) experience poorer health than their majority counterparts, but many measures of health inequity remain unexamined in population-based research.

Purpose: To describe a wide range of health status and healthcare access characteristics of sexual minorities in comparison with those of the majority population in a national sample of U.S.

Association between arsenic, cadmium, manganese, and lead levels in private wells and birth defects prevalence in North Carolina: a semi-ecologic study.

Background: Toxic metals including arsenic, cadmium, manganese, and lead are known human developmental toxicants that are able to cross the placental barrier from mother to fetus. In this population-based study, we assess the association between metal concentrations in private well water and birth defect prevalence in North Carolina.

Methods: A semi-ecologic study was conducted including 20,151 infants born between 2003 and 2008 with selected birth defects (cases) identified by the North Carolina Birth Defects Monitoring Program, and 668,381 non-malformed infants (controls).

A marginalized zero-inflated Poisson regression model with overall exposure effects.

The zero-inflated Poisson (ZIP) regression model is often employed in public health research to examine the relationships between exposures of interest and a count outcome exhibiting many zeros, in excess of the amount expected under sampling from a Poisson distribution. The regression coefficients of the ZIP model have latent class interpretations, which correspond to a susceptible subpopulation at risk for the condition with counts generated from a Poisson distribution and a non-susceptible subpopulation that provides the extra or excess zeros. The ZIP model parameters, however, are not well suited for inference targeted at marginal means, specifically, in quantifying the effect of an explanatory variable in the overall mixture population.

Correlates of adolescent and young adult sexual initiation patterns.

Context: Identifying adolescent characteristics associated with different patterns of sexual initiation is critical to promoting healthy sexual development.

Methods: Patterns of sexual initiation were examined among 12,378 respondents to Waves 1 (1994-1995) and 4 (2008) of the National Longitudinal Study of Adolescent Health. Multinomial logistic regression explored associations between adolescent characteristics and membership in five latent classes capturing the timing, sequence, pace and variety of sexual initiation patterns.

Acute systemic rapamycin induces neurobehavioral alterations in rats.

Rapamycin is a drug with antiproliferative and immunosuppressive properties, widely used for prevention of acute graft rejection and cancer therapy. It specifically inhibits the activity of the mammalian target of rapamycin (mTOR), a protein kinase known to play an important role in cell growth, proliferation and antibody production. Clinical observations show that patients undergoing therapy with immunosuppressive drugs frequently suffer from affective disorders such as anxiety or depression.

Eighteen year weight trajectories and metabolic markers of diabetes in modernising China.

Aims/hypothesis: Although obesity is a major risk factor for diabetes, little is known about weight gain trajectories across adulthood, and whether they are differentially associated with metabolic markers of diabetes.

Methods: We used fasting blood samples and longitudinal weight data for 5,436 adults (5,734 observations, aged 18-66 years) from the China Health and Nutrition Survey (1991-2009). Using latent class trajectory analysis, we identified different weight gain trajectories in six age and sex strata, and used multivariable general linear mixed effects models to assess elevated metabolic markers of diabetes (fasting glucose, HbA1c, HOMA-IR, insulin) across weight trajectory classes.

Genetic evaluation of aspects of temperament in Nellore-Angus calves.

The objective of this work was to estimate heritability of each of 5 subjectively measured aspects of temperament of cattle and the genetic correlations of pairs of those traits. From 2003 to 2013, Nellore-Angus F2 and F3 calves (n = 1,816) were evaluated for aspects of temperament at an average 259 d of age, which was approximately 2 mo after weaning. Calves were separated from a group and subjectively scored from 1 (calm, good temperament) to 9 (wild, poor temperament) for aggressiveness (willingness to hit an evaluator), nervousness, flightiness, gregariousness (willingness to separate from the group), and a distinct overall score by 4 evaluators.

Diuretic exposure in premature infants from 1997 to 2011.

Objective: Diuretics are often prescribed off-label to premature infants, particularly to prevent or treat bronchopulmonary dysplasia. We examined their use and safety in this group.

Study Design: Retrospective cohort study of infants < 32 weeks gestation and < 1,500 g birth weight exposed to diuretics in 333 neonatal intensive care units from 1997 to 2011.

Peri-implantation intercourse lowers fecundability.

Objective: To determine the impact of sexual intercourse around the time of implantation on the probability of achieving a pregnancy.

Design: Time-to-pregnancy cohort using day-specific probability of pregnancy modeling to account for intercourse during the fertile window.

Setting: Community cohort.

Maternal exposure to criteria air pollutants and congenital heart defects in offspring: results from the national birth defects prevention study.

Background: Epidemiologic literature suggests that exposure to air pollutants is associated with fetal development.

Objectives: We investigated maternal exposures to air pollutants during weeks 2-8 of pregnancy and their associations with congenital heart defects.

Methods: Mothers from the National Birth Defects Prevention Study, a nine-state case-control study, were assigned 1-week and 7-week averages of daily maximum concentrations of carbon monoxide, nitrogen dioxide, ozone, and sulfur dioxide and 24-hr measurements of fine and coarse particulate matter using the closest air monitor within 50 km to their residence during early pregnancy.

A multiple imputation method for sensitivity analyses of time-to-event data with possibly informative censoring.

This article presents a multiple imputation method for sensitivity analyses of time-to-event data with possibly informative censoring. The imputed time for censored values is drawn from the failure time distribution conditional on the time of follow-up discontinuation. A variety of specifications regarding the post-discontinuation tendency of having events can be incorporated in the imputation through a hazard ratio parameter for discontinuation versus continuation of follow-up.

The July Effect: is emergency department length of stay greater at the beginning of the hospital academic year?

Introduction: There has been concern of increased emergency department (ED) length of stay (LOS) during the months when new residents are orienting to their roles. This so-called "July Effect" has long been thought to increase LOS, and potentially contribute to hospital overcrowding and increased waiting time for patients. The objective of this study is to determine if the average ED LOS at the beginning of the hospital academic year differs for teaching hospitals with residents in the ED, when compared to other months of the year, and as compared to non-teaching hospitals without residents.

Association of physical activity in the past year and immediately after in vitro fertilization on pregnancy.

Objective: To estimate the association of physical activity on in vitro fertilization (IVF).

Design: Prospective cohort study.

Setting: Academic infertility clinic.

Single nucleotide polymorphisms in nucleotide excision repair genes, cancer treatment, and head and neck cancer survival.

Purpose: Head and neck cancers (HNC) are commonly treated with radiation and platinum-based chemotherapy, which produce bulky DNA adducts to eradicate cancerous cells. Because nucleotide excision repair (NER) enzymes remove adducts, variants in NER genes may be associated with survival among HNC cases both independently and jointly with treatment.

Methods: Cox proportional hazards models were used to estimate race-stratified (White, African American) hazard ratios (HRs) and 95 % confidence intervals for overall (OS) and disease-specific (DS) survival based on treatment (combinations of surgery, radiation, and chemotherapy) and 84 single nucleotide polymorphisms (SNPs) in 15 NER genes among 1,227 HNC cases from the Carolina Head and Neck Cancer Epidemiology Study.

Trends in caffeine use and association between clinical outcomes and timing of therapy in very low birth weight infants.

Objective: To examine the effect of early initiation of caffeine therapy on neonatal outcomes and characterize the use of caffeine therapy in very low birth weight (VLBW) infants.

Study Design: We analyzed a cohort of 62 056 VLBW infants discharged between 1997 and 2010 who received caffeine therapy. We compared outcomes in infants receiving early caffeine therapy (initial dose before 3 days of life) and those receiving late caffeine therapy (initial dose at or after 3 days of life) through propensity scoring using baseline and early clinical variables.

Insights into the transport of aqueous quaternary ammonium cations: a combined experimental and computational study.

This study focuses on understanding the relative effects of ammonium substituent groups (we primarily consider tetramethylammonium, benzyltrimethylammonium, and tetraethylammonium cations) and anion species (OH(-), HCO3(-), CO3(2-), Cl(-), and F(-)) on ion transport by combining experimental and computational approaches. We characterize transport experimentally using ionic conductivity and self-diffusion coefficients measured from NMR. These experimental results are interpreted using simulation methods to describe the transport of these cations and anions considering the effects of the counterion.

ED placement of perineural catheters for femoral fracture pain management.

Regional nerve blocks provide superior analgesia over opioid-based pain management regimens for traumatic injuries such as femur fractures. An ultrasound-guided regional nerve block is placed either as a single-shot injection or via a perineural catheter that is left in place. Although perineural catheters are commonplace in the perioperative setting, their use by emergency physicians (EPs) for emergency pain management in adults has not been previously described.

Replication of breast cancer susceptibility loci in whites and African Americans using a Bayesian approach.

Genome-wide association studies (GWAS) and candidate gene analyses have led to the discovery of several dozen genetic polymorphisms associated with breast cancer susceptibility, many of which are considered well-established risk factors for the disease. Despite attempts to replicate these same variant-disease associations in African Americans, the evaluable populations are often too small to produce precise or consistent results. We estimated the associations between 83 previously identified single nucleotide polymorphisms (SNPs) and breast cancer among Carolina Breast Cancer Study (1993-2001) participants using maximum likelihood, Bayesian, and hierarchical methods.

Breast cancer subtypes and previously established genetic risk factors: a bayesian approach.

Background: Gene expression analyses indicate that breast cancer is a heterogeneous disease with at least five immunohistologic subtypes. Despite growing evidence that these subtypes are etiologically and prognostically distinct, few studies have investigated whether they have divergent genetic risk factors. To help fill in this gap in our understanding, we examined associations between breast cancer subtypes and previously established susceptibility loci among white and African-American women in the Carolina Breast Cancer Study.

An evaluation of metrics for assessing maternal exposure to agricultural pesticides.

We evaluate the use of three different exposure metrics to estimate maternal agricultural pesticide exposure during pregnancy. Using a geographic information system-based method of pesticide exposure estimation, we combine data on crop density and specific pesticide application amounts/dates to create the three exposure metrics. For illustration purposes, we create each metric for a North Carolina cohort of pregnant women, 2003-2005, and analyze the risk of congenital anomaly development with a focus on metric comparisons.

Longitudinal trajectories of BMI and cardiovascular disease risk: the national longitudinal study of adolescent health.

Objective: In adulthood, excess BMI is associated with cardiovascular disease (CVD); it is unknown whether risk differs by BMI trajectories from adolescence to adulthood.

Design And Methods: The National Longitudinal Study of Adolescent Health, a nationally representative, longitudinal adolescent cohort (mean age: 16.9 years) followed into adulthood (mean age: 28.

Ultrasound-guided Intraarticular Hip Injection for Osteoarthritis Pain in the Emergency Department.

Ultrasound-guided intraarticular hip corticosteroid injections may be useful for emergency care providers treating patients with painful exacerbations of osteoarthritis of the hip. Corticosteroid injection is widely recommended as a first-line treatment for painful osteoarthritis of the hip. Bedside ultrasound is readily available in most emergency departments; however, using ultrasound to guide therapeutic hip injections has not yet been described in emergency practice.

High-intensity emergency department visits increased in California, 2002-09.

Increasing use of the emergency department (ED) is well documented, but little is known about the type and severity of ED visits or their distribution across safety-net and non-safety-net hospitals. We examined the rates of high-intensity ED visits--characterized by their use of advanced imaging, consultations with specialists, the evaluation of multiple systems, and highly complex medical decision making--by patients with a severe, potentially life-threatening illness in California from 2002 through 2009. Total annual ED visits increased by 25 percent, from 9.