Designing prospective cohort studies for assessing reproductive and developmental toxicity during sensitive windows of human reproduction and development--the LIFE Study.

The relationship between the environment and human fecundity and fertility remains virtually unstudied from a couple-based perspective in which longitudinal exposure data and biospecimens are captured across sensitive windows. In response, we completed the LIFE Study with methodology that intended to empirically evaluate a priori purported methodological challenges: implementation of population-based sampling frameworks suitable for recruiting couples planning pregnancy; obtaining environmental data across sensitive windows of reproduction and development; home-based biospecimen collection; and development of a data management system for hierarchical exposome data. We used two sampling frameworks (i.

Concentrations of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) and their associations with human semen quality measurements.

A total of 256 men were studied to evaluate whether serum concentrations of perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) impacted semen quality or reproductive hormones. Blood and semen were collected and analyzed for perfluorochemicals and reproductive and thyroid hormones. Semen quality was assessed using standard clinical methods.

Mass commuting and influenza vaccination prevalence in new york city: protection in a mixing environment.

Objective: Assess influenza vaccination among commuters using mass transit in New York City (NYC).

Methods: We used the 2006 NYC Community Health Survey (CHS) to analyze the prevalence of influenza immunization by commuting behaviors and to understand what socioeconomic and geographic factors may explain any differences found.

Results: Vaccination prevalence is significantly lower for New Yorkers who commute on public transportation compared to other New Yorkers.

Association of endodontic involvement with tooth loss in the Veterans Affairs Dental Longitudinal Study.

Introduction: The effect of endodontic involvement on tooth loss has not been quantified, so the present study aimed to assess this relationship after controlling for other relevant risk factors for tooth loss.

Methods: We analyzed data from 791 participants (18,798 teeth) in the Veterans Affairs Dental Longitudinal Study. Potential tooth-level and person-level covariates were fitted into marginal proportional hazards models, including both apical radiolucencies (AR) and root canal therapy (RCT) status as time-dependent variables.

Extension and density of root fillings and postoperative apical radiolucencies in the Veterans Affairs Dental Longitudinal Study.

We evaluated the association between radiographically assessed extension and density of root canal fillings and postoperative apical radiolucencies (ARs) by using data from 288 participants in the Veterans Affairs Dental Longitudinal Study. Study subjects were not Veterans Affairs patients; all received their medical and dental care in the private sector. Generalized estimating equations were used to account for multiple teeth within subjects and to control for covariates of interest.