Publications by authors named "Megan J Leonhard"

Objectives: The aim of this study was to update a cohort of Vermont talc workers to include 37 additional years of follow-up time.

Methods: Standardized mortality ratios (SMR) and 95% confidence intervals (CIs) were calculated for 70+ causes of death. US population mortality rates were used as reference.

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Background: Neurotoxic effects of high-level occupational exposure to manganese (Mn) are well established; however, whether lower-level environmental exposure to Mn in early life causes neurodevelopmental toxicity in children is unclear.

Methods: A systematic literature review was conducted to identify and evaluate epidemiologic studies of specific Mn biomarkers assessed during gestation, childhood, or adolescence in association with neurodevelopmental outcomes, focusing on quantitative exposure-response estimates with specific endpoints that were assessed in multiple independent study populations. Study quality was evaluated using the revised RTI item bank and the Cochrane Risk of Bias tool, and the overall weight of epidemiologic evidence for causality was evaluated according to the Bradford Hill considerations.

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Aims: We assessed the animal and epidemiological data to determine if chloroform exposure causes developmental and/or reproductive toxicity.

Results And Discussion: Initial scoping identified developmental toxicity as the primary area of concern. At levels producing maternal toxicity in rats and mice, chloroform caused decrements in fetal weights and associated delays in ossification.

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Article Synopsis
  • Advanced heart failure can be treated conservatively or with aggressive methods, such as left ventricular assist devices (LVADs) and heart transplants, and this review focuses on analyzing the cost-effectiveness of LVADs.
  • From 2006 to 2017, 12 cost-effectiveness studies on LVADs were identified, mostly exploring their use as destination therapy or as a bridge to transplant, utilizing various models and clinical data sources.
  • Overall, no studies concluded that LVADs were cost-effective for both treatment approaches, although some analyses indicated potential cost-effectiveness under certain conditions, highlighting the need for ongoing evaluation as LVAD technology evolves.
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Background: Air ions are molecules of air that have become ionized-that is, they have either lost or gained an electrical charge. Past speculation has suggested that exposure to positive air ions may be harmful to one's health, while exposure to negative air ions may be associated with beneficial health effects. Air ions arise from natural sources as well as direct-current transmission lines and commercial ionizers.

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Autism spectrum disorder (ASD) and attention deficit (hyperactivity) disorder (ADD/ADHD) are key focuses of current health research due to their increasing prevalence. The objective of this systematic literature search and critical review was to evaluate whether the human epidemiologic data indicate a pattern of association between ASD or ADD/ADHD and developmental exposure to particulate matter (PM), with a focus on exposures encountered before the age of three. A MEDLINE and EMBASE search was conducted; following preliminary and full-text screening, 14 relevant articles were identified for review.

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Background: Traumatic brain injury (TBI) greatly contributes to morbidity and mortality in the pediatric population. We examined potential urban/rural disparities in mortality amongst Oregon pediatric patients with TBI treated in trauma hospitals.

Methods: We conducted a retrospective study of children ages 0-19 using the Oregon Trauma Registry for years 2009-2012.

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