John A. McGrath
Durham University
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Featured researches published by John A. McGrath.
The Lancet. Public health | 2017
Richard K. Kwok; John A. McGrath; Sarah R. Lowe; Lawrence S. Engel; W. Braxton Jackson; Matthew D. Curry; Julianne Payne; Sandro Galea; Dale P. Sandler
BACKGROUND Adverse mental health effects have been reported following oil spills but few studies have identified specific responsible attributes of the clean-up experience. We aimed to analyse the effects of the 2010 Deepwater Horizon (Gulf of Mexico) disaster on the mental health of individuals involved in oil spill response and clean-up. METHODS We used data from the Gulf Long-term Follow-up Study, a cohort of workers and volunteers involved in oil spill clean-up after the Deepwater Horizon disaster. We included 8968 workers (hired after completing training for oil spill response and clean-up) and 2225 non-workers (completed training but were not hired) who completed a Patient Health Questionnaire-8 and four-item Primary Care PTSD Screen to assess for probable depression and post-traumatic stress disorder (PTSD) indicators. Participants were recruited between March 28, 2011, and March 29, 2013. The mental health indicators were assessed at home visits done between May 12, 2011, and May 15, 2013. We used regression models to analyse the effect of potentially stressful job experiences, job type, and total hydrocarbon exposure on mental health indicators. FINDINGS Oil spill response and clean-up work was associated with increased prevalence of depression (prevalence ratio [PR] 1·22, 95% CI 1·08-1·37) and PTSD (PR 1·35, 95% CI 1·07-1·71). Among workers, individuals who reported smelling oil, dispersants, or cleaning chemicals had an elevated prevalence of depression (1·56, 1·37-1·78) and PTSD (2·25, 1·71-2·96). Stopping work because of the heat was also associated with depression (1·37, 1·23-1·53) and PTSD (1·41, 1·15-1·74), as was working as a commercial fisherman before the spill (1·38, 1·21-1·57; and 2·01, 1·58-2·55, respectively). An increase in exposure to total hydrocarbons appeared to be associated with depression and PTSD, but after taking into account oil spill job experiences, only the association between the highest amount of total hydrocarbons and PTSD remained (1·75, 1·11-2·76). INTERPRETATION Oil spill clean-up workers with high amounts of total hydrocarbon exposure or potentially stressful job experiences had an increased prevalence of depression and PTSD. These findings provide evidence that response and clean-up work is associated with adverse psychological effects and suggest the need for mental health services both before and after the event. FUNDING National Institutes of Health (NIH) Common Fund and the Intramural Research Program of the NIH, National Institute of Environmental Health Sciences.
Journal of Toxicology and Environmental Health | 2017
Lawrence S. Engel; Richard K. Kwok; Aubrey Miller; Aaron Blair; Matthew D. Curry; John A. McGrath; Dale P. Sandler
ABSTRACT The 2010 Deepwater Horizon (DWH) explosion in the Gulf of Mexico led to the largest ever marine oil spill by volume. The GuLF STUDY is investigating possible adverse human health effects associated with oil spill activities. One objective of the study was to utilize biological specimens from study participants to examine spill-related adverse health effects. This study describes the methods for collecting, processing, shipping, and storing specimens during the enrollment phase of the study. GuLF STUDY participants living in Gulf States (Alabama, Florida, Louisiana, Mississippi, and eastern Texas) were eligible to complete a home visit at enrollment, one to three years after the DWH explosion. During this visit, blood, urine, toenail and hair clippings, and house dust samples were collected. Specimens were shipped overnight to a central processing laboratory in containers with cold and ambient temperature compartments. Most blood and urine specimens were then aliquoted and stored in liquid nitrogen vapor or at -80°C, with some samples stored at -20°C. A total of 11,193 participants completed a home visit, and over 99% provided at least one biospecimen. Most participants provided blood (93%), urine (99%), and toenail clippings (89%), and 40% provided hair. Nearly all participants (95%) provided house-dust samples. Most samples were received by the laboratory one (58%) or two (25%) days after collection. These biospecimens enable investigation of a range of biomarkers of spill-related adverse health effects, and possibly some biomarkers of spill-related exposures. The biospecimen collection, handling, and storage protocols were designed to maximize current and future scientific value within logistical and budgetary constraints and might serve as a template for future studies conducted in similar time-critical and geographically dispersed settings.
The Journal of Clinical Endocrinology and Metabolism | 2018
Bob Z Sun; Tairmae Kangarloo; Judith M. Adams; Patrick M. Sluss; Corrine K. Welt; Donald Walt Chandler; David T Zava; John A. McGrath; David M. Umbach; Janet E. Hall; Natalie D. Shaw
Context Menstrual irregularity after menarche has been attributed to immature estrogen positive feedback activity (E+FB) but data are conflicting. Objective To determine the hypothalamic-pituitary-ovarian contributions to menstrual irregularity in adolescents. Methods Twenty-three healthy girls [aged 12.8 to 17.6 years; 0.4 to 3.5 years postmenarche; body mass index (BMI) percentile, 41.0 to 99.3] underwent serial hormone measurements and pelvic ultrasounds during two consecutive menstrual cycles. Hormones and follicle growth were compared with 65 adult historic controls with ovulatory cycles (OVs). Results Girls had anovulatory cycles (ANOVs; 30%), OVs with a short luteal phase (short OVs; 22%), or OVs with normal luteal phase (normal OVs; 48%) without differences in cycle length, chronologic or gynecologic age, or BMI. Adolescents showed a spectrum of E+FB [midcycle LH adjusted for preovulatory estradiol (E2)]; only normal OV girls were comparable to adults. All OV girls had lower E2, progesterone, and gonadotropins during the luteal phase and luteal-follicular transition compared with adults. Normal OV girls also had lower follicular phase LH and FSH levels, a longer follicular phase, a slower dominant follicle growth rate, and smaller estimated preovulatory follicle size than adults. Follicular phase E2 and inhibin B levels were lower in normal OV girls than in adults even after adjusting for differences in FSH and follicle size. Conclusions Early postmenarchal girls with normal OVs demonstrate mature E+FB but continue to have lower gonadotropin levels, diminished ovarian responsiveness, and decreased corpus luteum sex steroid synthesis compared with adults, indicating that reproductive axis maturity requires coordinated development of all components of the hypothalamic-pituitary-ovarian axis.
Environment International | 2018
Kaitlyn B. Gam; Lawrence S. Engel; Richard K. Kwok; Matthew D. Curry; Patricia A. Stewart; Mark Stenzel; John A. McGrath; W. Braxton Jackson; Maureen Y. Lichtveld; Dale P. Sandler
INTRODUCTION Oil spill response and cleanup (OSRC) workers had potentially stressful experiences during mitigation efforts following the 2010 Deepwater Horizon disaster. Smelling chemicals; skin or clothing contact with oil; heat stress; handling oily plants/wildlife or dead animal recovery; and/or being out of regular work may have posed a risk to worker respiratory health through psychological stress mechanisms. OBJECTIVE To evaluate the association between six potentially stressful oil spill experiences and lung function among OSRC workers 1-3 years following the Deepwater Horizon disaster, while controlling for primary oil spill inhalation hazards and other potential confounders. METHODS Of 6811 GuLF STUDY participants who performed OSRC work and completed a quality spirometry test, 4806 provided information on all exposures and confounders. We carried out complete case analysis and used multiple imputation to assess risk among the larger sample. Potentially stressful work experiences were identified from an earlier study of these workers. The lung function parameters of interest include the forced expiratory volume in 1 s (FEV1, mL), the forced vital capacity (FVC, mL) and the ratio (FEV1/FVC, %). RESULTS On average, participants in the analytic sample completed spirometry tests 1.7 years after the spill. Among workers with at least 2 acceptable FEV1 and FVC curves, workers with jobs that involved oily plants/wildlife or dead animal recovery had lower values for FEV1 (Mean difference: -53 mL, 95% CI: -84, -22), FVC (Mean difference: -45 mL, 95% CI: -81, -9) and FEV1/FVC (Mean difference: -0.44%, 95% CI: -0.80, -0.07) compared to unexposed workers in analyses using multiple imputation. CONCLUSIONS Workers involved in handling oily plants/wildlife or dead animal recovery had lower lung function than unexposed workers after accounting for other OSRC inhalation hazards.
American Journal of Physiology-gastrointestinal and Liver Physiology | 2018
Teminioluwa Ajayi; Cynthia L. Innes; Sara A. Grimm; Prashant Rai; Ryan Finethy; Jörn Coers; Xuting Wang; Douglas A. Bell; John A. McGrath; Shepherd H. Schurman; Michael B. Fessler
Crohns disease (CD) is a chronic inflammatory gastrointestinal disorder. Genetic association studies have implicated dysregulated autophagy in CD. Among risk loci identified are a promoter single nucleotide polymorphism (SNP)( rs13361189 ) and two intragenic SNPs ( rs9637876 , rs10065172 ) in immunity-related GTPase family M ( IRGM) a gene that encodes a protein of the autophagy initiation complex. All three SNPs have been proposed to modify IRGM expression, but reports have been divergent and largely derived from cell lines. Here, analyzing RNA-Sequencing data of human tissues from the Genotype-Tissue Expression Project, we found that rs13361189 minor allele carriers had reduced IRGM expression in whole blood and terminal ileum, and upregulation in ileum of ZNF300P1, a locus adjacent to IRGM on chromosome 5q33.1 that encodes a long noncoding RNA. Whole blood and ileum from minor allele carriers had altered expression of multiple additional genes that have previously been linked to colitis and/or autophagy. Notable among these was an increase in ileum of LTF (lactoferrin), an established fecal inflammatory biomarker of CD, and in whole blood of TNF, a key cytokine in CD pathogenesis. Last, we confirmed that risk alleles at all three loci associated with increased risk for CD but not ulcerative colitis in a case-control study. Taken together, our findings suggest that genetically encoded IRGM deficiency may predispose to CD through dysregulation of inflammatory gene networks. Gene expression profiling of disease target tissues in genetically susceptible populations is a promising strategy for revealing new leads for the study of molecular pathogenesis and, potentially, for precision medicine. NEW & NOTEWORTHY Single nucleotide polymorphisms in immunity-related GTPase family M ( IRGM), a gene that encodes an autophagy initiation protein, have been linked epidemiologically to increased risk for Crohns disease (CD). Here, we show for the first time that subjects with risk alleles at two such loci, rs13361189 and rs10065172 , have reduced IRGM expression in whole blood and terminal ileum, as well as dysregulated expression of a wide array of additional genes that regulate inflammation and autophagy.
Journal of Occupational and Environmental Medicine | 2018
Kaitlyn B. Gam; Richard K. Kwok; Lawrence S. Engel; Matthew D. Curry; Patricia A. Stewart; Mark Stenzel; John A. McGrath; W. Braxton Jackson; Robert L. Jensen; Maureen Y. Lichtveld; Aubrey Miller; Dale P. Sandler
Epidemiology | 2018
Kaitlyn B. Gam; Richard K. Kwok; Lawrence S. Engel; Matthew D. Curry; Patricia A. Stewart; Mark Stenzel; John A. McGrath; W. Braxton Jackson; Robert L. Jensen; Alexander P. Keil; Maureen Y. Lichtveld; Aubrey Miller; Dale P. Sandler
Scientific Reports | 2018
Shepherd H. Schurman; Mercedes A. Bravo; Cynthia L. Innes; W. Braxton Jackson; John A. McGrath; Marie Lynn Miranda; Stavros Garantziotis
Annals of Epidemiology | 2017
Lydia Feinstein; Kaitlyn B. Gam; Matthew D. Curry; W. Braxton Jackson; John A. McGrath; Richard K. Kwok; Lawrence S. Engel; Dale P. Sandler
Annals of Epidemiology | 2017
Anna J. Ciesielski Jones; John A. McGrath; Lydia Feinstein; Rui Liu; Christie Barker-Cummings; Juliana W. Meadows; James S. Kesner; Michele Marcus; Dale P. Sandler