Publications by authors named "Tracy Nelson"

Early B cell factor 1 (EBF1) is a transcription factor expressed by multiple lineages of stromal cells within the bone marrow. While cultures of Ebf1-deficient cells have been demonstrated to have impaired differentiation into either the osteoblast or adipogenic lineage in vitro by several groups, in vivo there has been a nominal consequence of the loss of EBF1 on skeletal development. In this study we used Prx-cre driven deletion of Ebf1 to eliminate EBF1 from the entire mesenchymal lineage of the skeleton and resolve this discrepancy.

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Background: The purpose of this study was to evaluate the effectiveness of the physical domain (PD) to improve performance in all the POTFF domains (physical, psychological, social/family, and spiritual) among Special Forces (SF) Operators.

Methods: This was a cross-sectional study of active SF Operators assigned to the United States Army Special Operations Command (USASOC). Recruitment began in October 2016.

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Despite overwhelming adoption of wearable fitness trackers (WFT), it is unclear if they affect physical activity (PA) engagement or PA motivation. We hypothesized that combining a WFT with an effective intervention, motivational interviewing (MI), would positively influence both motivation and PA. A 12-week randomized controlled trial was conducted in 40 adults who did not meet PA recommendations.

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Childhood obesity is an ongoing concern in the United States. Higher weight status in early childhood is associated with higher weight status at older ages. The Maternal Obesity Matters (MOMs) Study investigated associations between maternal risk of cardiovascular disease (CVD) and child BMI z-scores (BMIz) among preschool-aged children.

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Household air pollution from solid fuel combustion was estimated to cause 2.31 million deaths worldwide in 2019; cardiovascular disease is a substantial contributor to the global burden. We evaluated the cross-sectional association between household air pollution (24-h gravimetric kitchen and personal particulate matter (PM) and black carbon (BC)) and C-reactive protein (CRP) measured in dried blood spots among 107 women in rural Honduras using wood-burning traditional or Justa (an engineered combustion chamber) stoves.

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Comparing twins from same- and opposite-sex pairs can provide information on potential sex differences in a variety of outcomes, including socioeconomic-related outcomes such as educational attainment. It has been suggested that this design can be applied to examine the putative role of intrauterine exposure to testosterone for educational attainment, but the evidence is still disputed. Thus, we established an international database of twin data from 11 countries with 88,290 individual dizygotic twins born over 100 years and tested for differences between twins from same- and opposite-sex dizygotic pairs in educational attainment.

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Importance: Detailed analysis of infection rates paired with behavioral and employee-reported risk factors is vital to understanding how transmission of SARS-CoV-2 infection may be exacerbated or mitigated in the workplace. Institutions of higher education are heterogeneous work units that supported continued in-person employment during the COVID-19 pandemic, providing a test site for occupational health evaluation.

Objective: To evaluate the association between self-reported protective behaviors and prevalence of SARS-CoV-2 infection among essential in-person employees during the first 6 months of the COVID-19 pandemic in the US.

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We examined the associations of autonomous motivation, controlled motivation, and physical activity (PA) planning with PA participation over six years across the adolescent-to-adult transition. Participants from the NEXT Generation Health Study, a nationally representative cohort study of U.S.

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Inactivating mutations in human ecto-nucleotide pyrophosphatase/phosphodiesterase-1 (ENPP1) may result in early-onset osteoporosis (EOOP) in haploinsufficiency and autosomal recessive hypophosphatemic rickets (ARHR2) in homozygous deficiency. ARHR2 patients are frequently treated with phosphate supplementation to ameliorate the rachitic phenotype, but elevating plasma phosphorus concentrations in ARHR2 patients may increase the risk of ectopic calcification without increasing bone mass. To assess the risks and efficacy of conventional ARHR2 therapy, we performed comprehensive evaluations of ARHR2 patients at two academic medical centers and compared their skeletal and renal phenotypes with ENPP1-deficient Enpp1 mice on an acceleration diet containing high phosphate treated with recombinant murine Enpp1-Fc.

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Background: Regular physical activity (PA) promotes health and can prevent and treat diseases among both humans and dogs. Unfortunately, most U.S.

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Objectives: Individuals with type 2 diabetes are at risk for deficits in instrumental activities of daily living (IADL: e.g., managing medication, preparing healthy meals).

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Objective: Characterize firefighters' acute stress and tiredness by duty status (ie, "off night/day," "on night/day").

Methods: Thirty nine career firefighters completed three, eight-day smartphone-based ecological momentary assessment periods with seven surveys per day assessing stress and tiredness. Mixed-effects location scale models examined duty status effects on stress and tiredness.

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We investigated the heritability of educational attainment and how it differed between birth cohorts and cultural-geographic regions. A classical twin design was applied to pooled data from 28 cohorts representing 16 countries and including 193,518 twins with information on educational attainment at 25 years of age or older. Genetic factors explained the major part of individual differences in educational attainment (heritability: a = 0.

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Objective: To systematically review the impacts of Wearable Fitness Trackers (WFTs), Motivational Interviewing (MI), and Self Determination Theory (SDT)-based interventions on physical activity (PA) and motivation for PA.

Data Source: Manuscripts published between 2008 and 2018 in PubMed, Web of Science, CABAbstracts, and SPORTDiscus database were reviewed.

Study Inclusion And Exclusion Criteria: Inclusion criteria were original pilot studies, randomized controlled trials (RCT), cross-sectional studies, qualitative assessments, prospective cohort studies, longitudinal observational studies, and pretest posttest designs published in peer-reviewed journals.

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Genetic factors explain a major proportion of human height variation, but differences in mean stature have also been found between socio-economic categories suggesting a possible effect of environment. By utilizing a classical twin design which allows decomposing the variation of height into genetic and environmental components, we tested the hypothesis that environmental variation in height is greater in offspring of lower educated parents. Twin data from 29 cohorts including 65,978 complete twin pairs with information on height at ages 1 to 69 years and on parental education were pooled allowing the analyses at different ages and in three geographic-cultural regions (Europe, North America and Australia, and East Asia).

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FGF-23 has arisen as an early biomarker of renal dysfunction, but at the onset of chronic kidney disease (CKD), data suggest that FGF-23 may be produced independently of the parathyroid hormone (PTH), 1,25(OH) -vitamin D signaling axis. Iron status is inversely correlated to the level of circulating FGF-23, and improvement in iron bioavailability within patients correlates with a decrease in FGF-23. Alternately, recent evidence also supports a regulatory role of inflammatory cytokines in the modulation of FGF-23 expression.

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The combination of poor diet and exposure to secondhand smoke may increase hemoglobin A1c (HbA1c) levels, but few studies have explored this interaction. We explored an interaction among 574 never-smoking adults from the Singapore Chinese Health Study. At baseline (age 59 ± 8 years), intakes of omega-3 polyunsaturated fatty acids, vitamin C, vitamin E and fiber were estimated using a modified food frequency questionnaire.

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One in four deaths in the US is caused by cardiovascular disease (CVD), and early detection may be a key aspect of prevention. We assessed the probability of a first hard atherosclerotic cardiovascular disease (ASCVD) event within 10 years in US Non-Hispanic White and African American population aged 40-79 years. With data from 16 years of the National Health and Nutrition Examination Survey (NHANES), we utilized the 2013 Pooled Cohort Equations developed by the American College of Cardiology and the American Heart Association to calculate risk scores for a representative sample.

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Household air pollution (HAP) is estimated to be an important risk factor for cardiovascular disease, but little clinical evidence exists and collecting biomarkers of disease risk is difficult in low-resource settings. Among 54 Nicaraguan women with woodburning cookstoves, we evaluated cross-sectional associations between 48-hour measures of HAP (eg, fine particulate matter, PM ) and C-reactive protein (CRP) via dried blood spots; secondary analyses included seven additional biomarkers of systemic injury and inflammation. We conducted sub-studies to calculate the intraclass correlation coefficient (ICC) in biomarkers collected over four consecutive days in Nicaragua and to assess the validity of measuring biomarkers in dried blood by calculating the correlation with paired venous-drawn samples in Colorado.

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Acute otitis media (AOM) is the most common diagnosis in childhood acute sick visits. By three years of age, 50% to 85% of children will have at least one episode of AOM. Symptoms may include ear pain (rubbing, tugging, or holding the ear may be a sign of pain), fever, irritability, otorrhea, anorexia, and sometimes vomiting or lethargy.

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Background: We recently showed the transcription factor Early B cell factor 1 (EBF1) is essential for the last stages of metanephric development, and that mice globally deficient in EBF1 display impaired maturation of peripheral glomeruli. EBF1 is present within multiple glomerular cell types, including the glomerular mesangium and podocytes.

Methods: To identify which cell type is driving the glomerular developmental defects in the global EBF1 knockout mice, we deleted EBF1 from the mesangium/pericytes (Foxd1-cre) or podocytes (Podocin-cre) in mice.

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Background: Growing evidence links household air pollution exposure from biomass-burning cookstoves to cardiometabolic disease risk. Few randomized controlled interventions of cookstoves (biomass or otherwise) have quantitatively characterized changes in exposure and indicators of cardiometabolic health, a growing and understudied burden in low- and middle-income countries (LMICs). Ideally, the solution is to transition households to clean cooking, such as with electric or liquefied petroleum gas stoves; however, those unable to afford or to access these options will continue to burn biomass for the foreseeable future.

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Objective: The objective of this study was to analyze how parental education modifies the genetic and environmental variances of BMI from infancy to old age in three geographic-cultural regions.

Methods: A pooled sample of 29 cohorts including 143,499 twin individuals with information on parental education and BMI from age 1 to 79 years (299,201 BMI measures) was analyzed by genetic twin modeling.

Results: Until 4 years of age, parental education was not consistently associated with BMI.

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Household air pollution from combustion of solid fuels is an important risk factor for morbidity and mortality, causing an estimated 2.6 million premature deaths globally in 2016. Self-reported health symptoms are a meaningful measure of quality of life, however, few studies have evaluated symptoms and quantitative measures of exposure to household air pollution.

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