Metal mixtures are associated with increased anxiety during pregnancy.

Background: Exposure to low-dose toxic metals in the environment is ubiquitous. Several murine studies have shown metals induce anxiety-like behaviors, and mechanistic research supports that metals disrupt neurotransmitter signaling systems implicated in the pathophysiology of anxiety. In this study, we extend prior research by examining joint exposure to six metals in relation to maternal anxiety symptoms during pregnancy.

Maternal blood arsenic levels and associations with birth weight-for-gestational age.

Background: Among highly exposed populations, arsenic exposure in utero may be associated with decreased birth weight, however less is known about potential effects of arsenic exposure in urban communities without contaminated sources such as drinking water.

Objective: Investigate the association of blood arsenic levels with birth weight-for-gestational age categories within a prospective birth cohort study.

Design/methods: We analyzed 730 mother-infant dyads within the Programming Research in Obesity, GRowth, Environment and Social Stressors (PROGRESS) cohort in Mexico City.

Dentine biomarkers of prenatal and early childhood exposure to manganese, zinc and lead and childhood behavior.

Background: Metal exposure alters neurodevelopmental outcomes; little is known about critical windows of susceptibility when exposure exerts the strongest effect.

Objective: To examine associations between dentine biomarkers of manganese (Mn), zinc (Zn) and lead (Pb) and later childhood behaviors.

Methods: Subjects enrolled in a longitudinal birth cohort study in Mexico City provided naturally shed deciduous teeth.

Prenatal nitrate air pollution exposure and reduced child lung function: Timing and fetal sex effects.

Background: Prenatal particulate air pollution exposure may alter lung growth and development in utero in a time-sensitive and sex-specific manner, resulting in reduced lung function in childhood. Such relationships have not been examined for nitrate (NO).

Methods: We implemented Bayesian distributed lag interaction models (BDLIMs) to identify sensitive prenatal windows for the influence of NO on lung function at age 7 years, assessing effect modification by fetal sex.

Prenatal fine particulate exposure and early childhood asthma: Effect of maternal stress and fetal sex.

Background: The impact of prenatal ambient air pollution on child asthma may be modified by maternal stress, child sex, and exposure dose and timing.

Objective: We prospectively examined associations between coexposure to prenatal particulate matter with an aerodynamic diameter of less than 2.5 microns (PM) and maternal stress and childhood asthma (n = 736).

Phototherapy in psoriasis: a review of mechanisms of action.

Background: Phototherapy is one of the most efficacious treatment options for psoriasis. New, emerging studies are beginning to define the biologic mechanisms by which phototherapy improves psoriasis.

Methods: To provide an overview of the mechanisms thought to be responsible for the therapeutic effects of phototherapy, a review was performed on all relevant published studies in the Medline database from January 1, 1985, to August 15, 2011.

Noninvasive measurement of cardiac performance in recovery from exercise in heart failure patients.

Objective: To examine the association between cardiac performance during recovery and the severity of heart failure, as determined by clinical and cardiopulmonary exercise test responses.

Methods: As part of a retrospective cohort study, 46 heart failure patients and 13 normal subjects underwent cardiopulmonary exercise testing while cardiac output was measured using a noninvasive device. Cardiac output in recovery was expressed as the slope of a single exponential relationship between cardiac output and time; the recovery-time constant was assessed in relation to indices of cardiac function, along with clinical, functional, and cardiopulmonary exercise responses.

The lowest VE/VCO2 ratio during exercise as a predictor of outcomes in patients with heart failure.

Background: The lowest minute ventilation (VE) and carbon dioxide production (VCO(2)) ratio during exercise has been suggested to be the most stable and reproducible marker of ventilatory efficiency in patients with heart failure (HF). However, the prognostic power of this index is unknown.

Methods And Results: A total of 847 HF patients underwent cardiopulmonary exercise testing (CPX) and were followed for 3 years.

Quantification of the impaired cardiac output response to exercise in heart failure: application of a non-invasive device.

An impaired cardiac output (CO) response to exercise is a hallmark of chronic heart failure (CHF), and the degree to which CO is impaired is related to the severity of CHF and prognosis. However, practical methods for obtaining cardiac output during exercise are lacking, and what constitutes and impaired response is unclear. Forty six CHF patients and 13 normal subjects underwent cardiopulmonary exercise testing (CPX) while CO and other hemodynamic measurements at rest and during exercise were obtained using a novel, non-invasive, bioreactance device based on assessment of relative phase shifts of electric currents injected across the thorax, heart rate and ventricular ejection time.

End-tidal CO2 pressure and cardiac performance during exercise in heart failure.

Introduction: In patients with heart failure (HF), end-tidal CO2 pressure (PetCO2) is related to ventricular function at rest and has been shown to predict prognosis. However, little is known about the association between ventricular performance and PetCO2 responses to exercise.

Methods: Forty-eight patients with HF and 13 normal subjects underwent cardiopulmonary exercise testing (CPX), while cardiac output and other hemodynamic measurements at rest and during exercise were obtained using a novel, noninvasive, bioreactance device based on assessment of relative phase shifts of electric currents injected across the thorax, heart rate, and ventricular ejection time.

A cardiopulmonary exercise testing score for predicting outcomes in patients with heart failure.

Objective: The aim of this study is to evaluate the predictive accuracy of a cardiopulmonary exercise test (CPX) score.

Background: Cardiopulmonary exercise test responses, including peak VO(2), markers of ventilatory inefficiency (eg, the VE/VCO(2) slope and oxygen uptake efficiency slope [OUES]), and hemodynamic responses, such as heart rate recovery (HRR) and chronotropic incompetence (CRI) are strong predictors of outcomes in patients with heart failure (HF). However, there is a need for simplified approaches that integrate the additive prognostic information from CPX.

The minute ventilation/carbon dioxide production slope is prognostically superior to the oxygen uptake efficiency slope.

Background: Ventilatory efficiency, commonly assessed by the minute ventilation (VE)-carbon dioxide production (VCO2) slope, has proven to be a strong prognostic marker in the heart failure (HF) population. Recently, the oxygen uptake efficiency slope (OUES) has demonstrated prognostic value, but additional comparisons to established cardiopulmonary exercise test (CPET) variables are required.

Methods And Results: A total of 341 subjects were diagnosed with HF participated in this analysis.

Effects of exercise training on heart rate recovery in patients with chronic heart failure.

Background: Heart rate recovery (HRR) is a marker of vagal tone that is associated with survival, but little is known about the effects of exercise training on HRR in patients with heart failure (HF).

Methods: Twenty-four patients with HF were randomized to a 2-month residential rehabilitation program or to usual care. Symptom-limited exercise testing was performed at baseline and at discharge from the program.