Publications by authors named "Kevin Thomas"

473 Publications

Development of digital measures for nighttime scratch and sleep using wrist-worn wearable devices.

NPJ Digit Med 2021 Mar 3;4(1):42. Epub 2021 Mar 3.

Pfizer, Inc., Cambridge, MA, USA.

Patients with atopic dermatitis experience increased nocturnal pruritus which leads to scratching and sleep disturbances that significantly contribute to poor quality of life. Objective measurements of nighttime scratching and sleep quantity can help assess the efficacy of an intervention. Wearable sensors can provide novel, objective measures of nighttime scratching and sleep; however, many current approaches were not designed for passive, unsupervised monitoring during daily life. In this work, we present the development and analytical validation of a method that sequentially processes epochs of sample-level accelerometer data from a wrist-worn device to provide continuous digital measures of nighttime scratching and sleep quantity. This approach uses heuristic and machine learning algorithms in a hierarchical paradigm by first determining when the patient intends to sleep, then detecting sleep-wake states along with scratching episodes, and lastly deriving objective measures of both sleep and scratch. Leveraging reference data collected in a sleep laboratory (NCT ID: NCT03490877), results show that sensor-derived measures of total sleep opportunity (TSO; time when patient intends to sleep) and total sleep time (TST) correlate well with reference polysomnography data (TSO: r = 0.72, p < 0.001; TST: r = 0.76, p < 0.001; N = 32). Log transformed sensor derived measures of total scratching duration achieve strong agreement with reference annotated video recordings (r = 0.82, p < 0.001; N = 25). These results support the use of wearable sensors for objective, continuous measurement of nighttime scratching and sleep during daily life.
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http://dx.doi.org/10.1038/s41746-021-00402-xDOI Listing
March 2021

An fMRI investigation of neural activation predicting memory formation in children with fetal alcohol spectrum disorders.

Neuroimage Clin 2020 Dec 11;30:102532. Epub 2020 Dec 11.

Child Development Research Laboratory, University of Cape Town, Faculty of Health Sciences, Department of Human Biology, Cape Town, South Africa; Child Development Research Laboratory, University of Cape Town, Faculty of Health Sciences, Department of Psychiatry and Mental Health, Cape Town, South Africa; Child Development Research Laboratory, Wayne State University School of Medicine, Department of Psychiatry and Behavioral Neurosciences, Detroit, MI, USA. Electronic address:

Prenatal alcohol exposure (PAE) is associated with physical anomalies, growth restriction, and a range of neurobehavioral deficits. Although declarative memory impairment has been documented extensively in individuals with fetal alcohol spectrum disorders (FASD), this cognitive process has been examined in only one functional magnetic resonance imaging (fMRI) study, and mechanisms underlying this impairment are not well understood. We used an event-related fMRI design to examine neural activations during visual scene encoding that predict subsequent scene memory in 51 right-handed children (age range = 10-14 years, M = 11.3, SD = 1.3) whose mothers had been recruited and interviewed prospectively about their alcohol use during pregnancy. Following examination by expert dysmorphologists, children were assigned to one of three FASD diagnostic groups: FAS/PFAS (n = 7; n = 4), nonsyndromal heavily exposed (HE; n = 14), and Controls (n = 26). Subsequent memory was assessed in a post-scan recognition test, and subsequent memory activations were examined by contrasting activations during encoding of scenes that were subsequently remembered (hits) to those for incorrectly judged as 'new' (misses). Recognition accuracy did not differ between groups. Pooled across groups, we observed extensive bilateral subsequent memory effects in regions including the hippocampal formation, posterior parietal cortex, and occipital cortex-a pattern consistent with previous similar studies of typically developing children. Critically, in the group of children with FAS or PFAS, we observed activations in several additional regions compared to HE and Control groups. Given the absence of between-group differences in recognition accuracy, these data suggest that in achieving similar memory compared to children in the HE and Control groups, children with FAS and PFAS recruit more extensive neural resources to achieve successful memory formation.
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http://dx.doi.org/10.1016/j.nicl.2020.102532DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7918676PMC
December 2020

Youth perinatal HIV-associated neurocognitive disorders: association with functional impairment.

AIDS Care 2021 Feb 24:1-5. Epub 2021 Feb 24.

Department of Psychiatry and Mental Health, University of Cape Town (UCT), Cape Town, South Africa.

HIV-associated functional impairment may cause cognitive impairment secondary to the viral infection, hence, associations between cognitive impairment and functional impairment in youth living with HIV are important to assess. We sought to determine whether cognitive impairment is associated with functional impairment and if it carries higher risk for also having functional impairment. We collected parent-rated information regarding youth functional impairment on four different measures and administered a cognitive battery to youth to determine cognitive impairment, 203 HIV-infected youth and 44 HIV-uninfected controls. Degree of cognitive impairment correlated strongly with decreased function: CBCL,  = -.17,  = .01; VABS2,  = -.28,  < .001; repeated-grades,  = .26,  < .001. Presence of cognitive impairment was associated with increased risk of functional impairment: 3.47 (CIS); 1.71 (CBCL); 2.17 (VABS2); 2.97 (repeated-grades). Repeated-grades strongly associated with cognitive impairment and functional impairment. We found strong associations between HIV-infected youth functional impairment on CBCL, VABS2 and repeated-grades with degree of cognitive impairment; and that when cognitive impairment was present youth had higher risk of experiencing functional impairment as well. Asking whether youth have repeated a grade at school could be a helpful screening question for assessing potential functional impairment and provide clinicians with an indication as to whether a further in-depth assessment is required.
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http://dx.doi.org/10.1080/09540121.2021.1891191DOI Listing
February 2021

Plastic particles in soil: state of the knowledge on sources, occurrence and distribution, analytical methods and ecological impacts.

Environ Sci Process Impacts 2021 Mar;23(2):240-274

Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, 20 Cornwall Street, Woolloongabba, QLD 4102, Australia.

Increased production and use of plastics has resulted in growth in the amount of plastic debris accumulating in the environment, potentially fragmenting into smaller pieces. Fragments <5 mm are typically defined as microplastics, while fragments <0.1 μm are defined as nanoplastics. Over the past decade, an increasing number of studies have reported the occurrence and potential hazards of plastic particles in the aquatic environment. However, less is understood about plastic particles in the terrestrial environment and specifically how much plastic accumulates in soils, the possible sources, potential ecological impacts, interaction of plastic particles with the soil environment, and appropriate extraction and analytical techniques for assessing the above. In this review, a comprehensive overview and a critical perspective on the current state of knowledge on plastic pollution in the soil environment is provided: detailing known sources, occurrence and distribution, analytical techniques used for identification and quantification and the ecological impacts of particles on soil. In addition, knowledge gaps are identified along with suggestions for future research.
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http://dx.doi.org/10.1039/d0em00312cDOI Listing
March 2021

Evaluation of Wearable Technology in Dementia: A Systematic Review and Meta-Analysis.

Front Med (Lausanne) 2020 11;7:501104. Epub 2021 Jan 11.

Department of Anatomy and Neurobiology, Boston University Medical Center, Boston, MA, United States.

The objective of this analysis was to systematically review studies employing wearable technology in patients with dementia by quantifying differences in digitally captured physiological endpoints. This systematic review and meta-analysis was based on web searches of Cochrane Database, PsycInfo, Pubmed, Embase, and IEEE between October 25-31st, 2017. Observational studies providing physiological data measured by wearable technology on participants with dementia with a mean age ≥50. Data were extracted according to PRISMA guidelines and methodological quality assessed independently using Downs and Black criteria. Standardized mean differences between cases and controls were estimated using random-effects models. Forty-eight studies from 18,456 screened abstracts (Dementia: = 2,516, Control: = 1,224) met inclusion criteria for the systematic review. Nineteen of these studies were included in one or multiple meta-analyses (Dementia: = 617, Control: = 406). Participants with dementia demonstrated lower levels of daily activity (standardized mean difference (SMD), -1.60; 95% CI, -2.66 to -0.55), decreased sleep efficiency (SMD, -0.52; 95% CI, -0.89 to -0.16), and greater intradaily circadian variability (SMD, 0.46; 95% CI, 0.27 to 0.65) than controls, among other measures. Statistical between-study heterogeneity was observed, possibly due to variation in testing duration, device type or patient setting. Digitally captured data using wearable devices revealed that adults with dementia were less active, demonstrated increased fragmentation of their sleep-wake cycle and a loss of typical diurnal variation in circadian rhythm as compared to controls.
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http://dx.doi.org/10.3389/fmed.2020.501104DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7829192PMC
January 2021

Understanding the Patient Experience: Analysis of 2-Word Assessment and Its Relationship to Likelihood to Recommend in Outpatient Hand Surgery.

Hand (N Y) 2021 Jan 21:1558944720988078. Epub 2021 Jan 21.

Stanford University, Redwood City, CA, USA.

Background: Actionable feedback from patients after a clinic visit can help inform ways to better deliver patient-centered care. A 2-word assessment may serve as a proxy for lengthy post-visit questionnaires. We tested the use of a 2-word assessment in an outpatient hand clinic.

Methods: New patients were asked to provide a 2-word assessment of the following: (1) their physician; (2) their overall experience; and (3) recommendations for improvement and their likelihood to recommend (LTR) after their clinic visit. Sentiment analysis was used to categorize results into positive, neutral, or negative sentiment. Recommendations for improvement were classified into physician issue, system issue, or neither. We evaluated the relationship between LTR status, sentiment, actionable improvement opportunities, and classification (physician issue, system issue, or neither). Recommendations for improvement were classified into themes based on prior literature.

Results: Sixty-seven (97.1%) patients noted positive sentiment toward their physician; 67 (97.1%) noted positive sentiment toward their overall experience. About 31% of improvement recommendations were system-based, 5.9% were physician-based, and 62.7% were neither. Patients not LTR were more likely to leave actionable opportunities for improvement than those LTR ( = .01). Recommendations for improvement were classified into predetermined themes relating to: (1) physician interaction; (2) check-in process; (3) facilities; (4) unnecessary visit; and (5) appointment delays.

Conclusion: Patients not likely to recommend provided actionable opportunities for improvement using a simple 2-word assessment. Implementation of a 2-word assessment in a hand clinic can be used to obtain actionable, real-time patient feedback that can inform operational change and improve the patient experience.
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http://dx.doi.org/10.1177/1558944720988078DOI Listing
January 2021

African American-Caucasian American differences in aortic valve replacement in patients with severe aortic stenosis.

Am Heart J 2021 Jan 13;234:111-121. Epub 2021 Jan 13.

Duke University School of Medicine, Durham, NC; Duke Clinical Research Institute, Durham, NC. Electronic address:

Background: Among patients with severe aortic stenosis (AS), there are limited data on aortic valve replacement (AVR), reasons for nonreceipt and mortality by race.

Methods: Utilizing the Duke Echocardiography Laboratory Database, we analyzed data from 110,711 patients who underwent echocardiography at Duke University Medical Center between 1999 and 2013. We identified 1,111 patients with severe AS who met ≥1 of 3 criteria for AVR: ejection fraction ≤50%, diagnosis of heart failure, or need for coronary artery bypass surgery. Logistic regression models were used to assess the association between race, AVR and 1-year mortality. χ2 testing was used to assess potential racial differences in reasons for AVR nonreceipt.

Results: Among the 1,111 patients (143 AA and 968 CA) eligible for AVR, AA were more often women, had more diabetes, renal insufficiency, aortic regurgitation and left ventricular hypertrophy. CA were more often smokers, had more ischemic heart disease, hyperlipidemia and higher median income levels. There were no racial differences in surgical risk utilizing logistic euroSCORES. Relative to CA, AA had lower rates of AVR (adjusted odds ratio 0.46, 95% CI 0.3-0.71, P < .001) yet similar 1-year mortality (aHR 0.81, 95% CI 0.57-1.17, P = .262). There were no significant differences in reasons for AVR nonreceipt.

Conclusions: We identified 143 African Americans (AA) and 968 Caucasian Americans(CA) with severe AS who met prespecified criteria for AVR.. AA relative to CA were more often women, had more diabetes, renal insufficiency, and left ventricular hypertrophy, however had less tobacco use, ischemic heart disease, hyperlipidemia and lower median income levels. Among patients with severe AS, AA relative to CA had lower rates of AVR (adjusted odds ratio 0.46, 95% CI 0.3-0.71, P < .001) without significant differences in reasons for AVR nonreceipt and similar 1-year mortality.
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http://dx.doi.org/10.1016/j.ahj.2021.01.005DOI Listing
January 2021

Racial Differences in AKI Incidence Following Percutaneous Coronary Intervention.

J Am Soc Nephrol 2021 Mar 18;32(3):654-662. Epub 2020 Dec 18.

Division of General Internal Medicine, Department of Medicine, Duke University School of Medicine, Durham, North Carolina.

Background: Undergoing percutaneous coronary intervention (PCI) is a risk factor for AKI development, but few studies have quantified racial differences in AKI incidence after this procedure.

Methods: We examined the association of self-reported race (Black, White, or other) and baseline eGFR with AKI incidence among patients who underwent PCI at Duke University Medical Center between January 1, 2003, and December 31, 2013. We defined AKI as a 0.3 mg/dl absolute increase in serum creatinine within 48 hours, or ≥1.5-fold relative elevation within 7 days post-PCI from the reference value ascertained within 30 days before PCI.

Results: Of 9422 patients in the analytic cohort (median age 63 years; 33% female; 75% White, 20% Black, 5% other race), 9% developed AKI overall (14% of Black, 8% of White, 10% of others). After adjustment for demographics, socioeconomic status, comorbidities, predisposing medications, PCI indication, periprocedural AKI prophylaxis, and PCI procedural characteristics, Black race was associated with increased odds for incident AKI compared with White race (odds ratio [OR], 1.79; 95% confidence interval [95% CI], 1.48 to 2.15). Compared with Whites, odds for incident AKI were not significantly higher in other patients (OR, 1.30; 95% CI, 0.93 to 1.83). Low baseline eGFR was associated with graded, higher odds of AKI incidence ( value for trend <0.001); however, there was no interaction between race and baseline eGFR on odds for incident AKI ( value for interaction = 0.75).

Conclusions: Black patients had greater odds of developing AKI after PCI compared with White patients. Future investigations should identify factors, including multiple domains of social determinants, that predispose Black individuals to disparate AKI risk after PCI.
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http://dx.doi.org/10.1681/ASN.2020040502DOI Listing
March 2021

Perceived Versus Actual Risks of 30-Day Readmission in Patients With Cardiovascular Disease.

Circ Cardiovasc Qual Outcomes 2021 Jan 12;14(1):e006586. Epub 2021 Jan 12.

Center for the Study of Aging and Human Development (H.X., M.E.D.), Duke University, Durham, NC.

Background: Cardiovascular disease (CVD) is the leading cause of hospitalization in the United States, and patients with CVD are at a high risk of readmission after discharge. We examined whether patients' perceived risk of readmission at discharge was associated with actual 30-day readmissions in patients hospitalized with CVD.

Methods: We recruited 730 patients from the Duke Heart Center who were admitted for treatment of CVD between January 1, 2015, and August 31, 2017. A standardized survey was linked with electronic health records to ascertain patients' perceived risk of readmission, and other sociodemographic, psychosocial, behavioral, and clinical data before discharge. All-cause readmission within 30 days after discharge was examined.

Results: Nearly 1-in-3 patients perceived a high risk of readmission at index admission and those who perceived a high risk had significantly more readmissions within 30 days than patients who perceived low risks of readmission (23.6% versus 15.8%, =0.016). Among those who perceived a high risk of readmission, non-White patients (odds ratio [OR], 2.07 [95% CI, 1.28-3.36]), those with poor self-rated health (OR, 2.30 [95% CI, 1.38-3.85]), difficulty accessing care (OR, 2.72 [95% CI, 1.24-6.00]), and prior hospitalizations in the past year (OR, 2.13 [95% CI, 1.21-3.74]) were more likely to be readmitted. Among those who perceived a low risk of readmission, patients who were widowed (OR, 2.69 [95% CI, 1.60-4.51]) and reported difficulty accessing care (OR, 1.89 [95% CI, 1.07-3.33]) were more likely to be readmitted.

Conclusions: Patients who perceived a high risk of readmission had a higher rate of 30-day readmission than patients who perceived a low risk. These findings have important implications for identifying CVD patients at a high risk of 30-day readmission and targeting the factors associated with perceived and actual risks of readmission.
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http://dx.doi.org/10.1161/CIRCOUTCOMES.120.006586DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7855013PMC
January 2021

Evaluation of Women and Underrepresented Racial and Ethnic Group Representation in a General Cardiology Fellowship After a Systematic Recruitment Initiative.

JAMA Netw Open 2021 Jan 4;4(1):e2030832. Epub 2021 Jan 4.

Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, North Carolina.

Importance: The proportion of women and underrepresented racial and ethnic groups (UREGs) matriculating into general cardiology fellowships remains low.

Objective: To assess a systematic recruitment initiative aimed at ensuring adequate matriculation of women and UREGs in a general cardiology fellowship.

Design, Setting, And Participants: This quality improvement study took place at a large, tertiary academic medical center and associated Accreditation Council for Graduate Medical Education Cardiovascular Disease fellowship. Participants included cardiology fellowship and divisional leadership and general cardiology fellow applicants to the Duke Cardiovascular Disease Fellowship Program from 2017 to 2019. Data analysis was performed from December 2019 to May 2020.

Exposure: Multipronged initiative that created an environment committed to ensuring equity of opportunity. This included the creation of a fellowship diversity and inclusivity task force that drafted recommendations, which included reorganization of the fellowship recruitment committee, and changes to the applicant screening process, the interview day, applicant ranking process, and postmatch interventions.

Main Outcomes And Measures: The percentage of matriculating and overall women and UREGs before and after the interventions were recorded.

Results: The fellowship received a mean (SD) of 462 (55) applications annually before the interventions (2006-2016) and 611 (27) applications annually after the interventions (2017-2019). Between the 10-year period before the interventions and the 3-year period during the interventions, there was a significant increase in the annual mean (SD) percentage of women (22.4% [2.9%] vs 26.4% [0.07%]; P < .001) and UREG applicants (10.5% [1.1%] vs 12.5% [1.9%]; P = .01) to the program. Among applicants interviewed, the percentage of women increased from 20.0% to 33.5% (P = .01) and that of and UREGs increased from 14.0% to 20.0% (P = .01). Before the interventions, a mean (SD) of 23.2% (16.2%) women and 9.7% (7.8%) UREGs matriculated as first-year fellows, whereas after the interventions, a mean (SD) of 54.2% (7.2%) women and 33.3% (19.0%) UREGs matriculated as first-year fellows. The proportion of the entire fellowship who were women increased from a 5-year mean (SD) of 27.0% (8.8%) to 54.2% (7.2%) after 3 years of interventions, and that of UREGs increased from 5.6% (4.6%) to 33.3% (19.0%). Overall, the proportion of applicants in the entire population who were either women or from UREGs increased from 27.8% to 66.7%.

Conclusions And Relevance: After implementing interventions to promote equity of opportunity in the cardiovascular disease fellowship, the percentage of women and UREGs significantly increased in the fellowship over a 3-year time period. These interventions may be applicable to other cardiovascular disease fellowships seeking to diversify training programs.
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http://dx.doi.org/10.1001/jamanetworkopen.2020.30832DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7801933PMC
January 2021

Augmenting E Protein Activity Impairs cDC2 Differentiation at the Pre-cDC Stage.

Front Immunol 2020 18;11:577718. Epub 2020 Dec 18.

Program in Arthritis and Clinical Immunology, Oklahoma Medical Research Foundation, Oklahoma City, OK, United States.

Dendritic cell (DC) specification and differentiation are controlled by a circuit of transcription factors, which regulate the expression of DC effector genes as well as the transcription factors themselves. E proteins are a widely expressed basic helix-loop-helix family of transcription factors whose activity is suppressed by their inhibitors, ID proteins. Loss-of-function studies have demonstrated the essential role of both E and ID proteins in different aspects of DC development. In this study, we employed a gain-of-function approach to illustrate the importance of the temporal control of E protein function in maintaining balanced differentiation of conventional DC (cDC) subsets, cDC1 and cDC2. We expressed an E protein mutant, ET2, which dimerizes with endogenous E proteins to overcome inhibition by ID proteins and activate the transcription of E protein targets. Induction of ET2 expression at the hematopoietic progenitor stage led to a dramatic reduction in cDC2 precursors (pre-cDC2s) with little impact on pre-cDC1s. Consequently, we observed decreased numbers of cDC2s in the spleen and lung, as well as in FLT3L-driven bone marrow-derived DC cultures. Furthermore, in mice bearing ET2, we detected increased expression of the IRF8 transcription factor in cDC2s, in which IRF8 is normally down-regulated and IRF4 up-regulated. This aberrant expression of IRF8 induced by ET2 may contribute to the impairment of cDC2 differentiation. In addition, analyses of the transcriptomes of splenic cDC1s and cDC2s revealed that ET2 expression led to a shift, at least in part, of the transcriptional profile characteristic of cDC2s to that of cDC1. Together, these results suggest that a precise control of E protein activity is crucial for balanced DC differentiation.
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http://dx.doi.org/10.3389/fimmu.2020.577718DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7775562PMC
December 2020

SARS-CoV-2 RNA monitoring in wastewater as a potential early warning system for COVID-19 transmission in the community: A temporal case study.

Sci Total Environ 2021 Mar 5;761:144216. Epub 2020 Dec 5.

Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, 20 Cornwall Street, Woolloongabba, QLD 4103, Australia.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus which causes coronavirus disease (COVID-19), has spread rapidly across the globe infecting millions of people and causing significant health and economic impacts. Authorities are exploring complimentary approaches to monitor this infectious disease at the community level. Wastewater-based epidemiology (WBE) approaches to detect SARS-CoV-2 RNA in municipal wastewater are being implemented worldwide as an environmental surveillance approach to inform health authority decision-making. Owing to the extended excretion of SARS-CoV-2 RNA in stool, WBE can surveil large populated areas with a longer detection window providing unique information on the presence of pre-symptomatic and asymptomatic cases that are unlikely to be screened by clinical testing. Herein, we analysed SARS-CoV-2 RNA in 24-h composite wastewater samples (n = 63) from three wastewater treatment plants (WWTPs) in Brisbane, Queensland, Australia from 24th of February to 1st of May 2020. A total of 21 samples were positive for SARS-CoV-2, ranging from 135 to 11,992 gene copies (GC)/100 mL of wastewater. Detections were made in a Southern Brisbane WWTP in late February 2020, up to three weeks before the first clininal case was reported there. Wastewater samples were generally positive during the period with highest caseload data. The positive SARS-CoV-2 RNA detection in wastewater while there were limited clinical reported cases demonstrates the potential of WBE as an early warning system to identify hotspots and target localised public health responses, such as increased individual testing and the provision of health warnings.
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http://dx.doi.org/10.1016/j.scitotenv.2020.144216DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7718102PMC
March 2021

Relationship between industry royalty and licensing payments and patent authorship among orthopedic spine surgeons.

Spine J 2020 Dec 23. Epub 2020 Dec 23.

Department of Orthopaedic Surgery, Stanford University, 430 Broadway Street, MC: 6342, Pavilion C, 4th Floor, Redwood City, CA 94063-6342.

Background Context: The Physician Payments Sunshine Act requires manufacturers of drugs, medical devices, medical supplies, and biologics to record all financial relationships with physicians in the Open Payments database with the goal of increasing transparency for patients and the general public. The majority of total money going to orthopedic surgeons has been found to go to a small number of surgeons in the form of royalties and licensing payments. This category of payment is intended to compensate physicians for use of their intellectual property. However, little research has been done to investigate the degree to which these physicians own intellectual property.

Purpose: To the authors' knowledge, the association between patents and industry payments to orthopedic surgeons has not been explored. We quantify the association between the patents and academic productivity of orthopedic spine surgeons and the amount of royalty and licensing fees they receive. We then compared this with the associations observed for other categories of payments.

Study Design: Cross-sectional study METHODS: Top royalty and licensing earners, defined as those who collectively earned 50% of all royalty and licensing payments over the period August 2013-December 2018, were identified. The h-index, publication count, and patent count of this group were compared with top earners of other payment categories using the Mann-Whitney U test. The association between (1) earnings and patent counts, (2) earnings and manuscript counts, and (3) earnings and h-index among the top royalty and licensing earners was assessed using Spearman correlation.

Results: Top royalty and licensing earners had significantly more patents than every comparison group except the top earners of money derived from ownership in a biomedical company. For this one exception, there was a trend toward the top eight royalty and licensing earners having more patents (p=.054). The top royalty and licensing earners had significantly more manuscripts than three of the five comparison groups and significantly higher h-indices than four of the five comparison groups. Among the top royalty and licensing earners, receiving more royalty and licensing payments was associated with holding more patents, but not with publishing more papers or having higher h-indices.

Conclusions: There is a strong association between the number of patents authored by individual orthopedic spine surgeons and the amount of royalty and licensing fees they receive from industry. This supports the hypothesis that these payments serve as compensation to inventor-surgeons for their intellectual property.

Clinical Significance: Our findings provide new, important context for the largest category of industry payments to orthopedic spine surgeons and suggests that physicians' patents should be considered when evaluating financial transactions between industry and physicians.
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http://dx.doi.org/10.1016/j.spinee.2020.12.003DOI Listing
December 2020

Antimicrobial resistance in United States retail ground beef with and without label claims regarding antibiotic use.

J Food Prot 2020 Dec 10. Epub 2020 Dec 10.

USDA-ARS Roman L Hruska US Meat Animal Research Center.

Antibiotics used during food-animal production account for approximately 77% of U.S. antimicrobial consumption by mass. Ground beef products labeled as raised without antibiotics (RWA) are perceived to harbor lower antimicrobial resistance (AMR) levels than conventional (CONV) products with no label claims regarding antimicrobial use. Retail ground beef samples were obtained from 6 U. S. cities. Samples with a RWA or USDA Organic claim ( N = 299) were assigned to the RWA production system. Samples lacking these claims ( N = 300) were assigned to the CONV production system. Each sample was cultured for the detection of five antimicrobial resistant bacteria. Genomic DNA was isolated from each sample and qPCR was used to determine the abundance of ten antimicrobial resistance genes (ARGs). Tetracycline-resistant Escherichia coli (CONV = 46.3%; RWA = 34.4%, P < 0.01) and erythromycin-resistant Enterococcus (CONV = 48.0%; RWA = 37.5%, P = 0.01) were more frequently detected in CONV. Salmonella were detected in 1.2% of samples. The ARG bla CTX-M (CONV = 4.1 log 10 normalized abundance, RWA = 3.8 log 10 normalized abundance, P < 0.01) was more abundant in CONV ground beef. The ARGs mecA (CONV = 4.4 log 10 normalized abundance, RWA = 4.9 log 10 normalized abundance, P = 0.05), tet (A) (CONV = 3.9 log 10 normalized abundance, RWA = 4.5 log 10 normalized abundance, P < 0.01), tet (B) (CONV = 3.9 log 10 normalized abundance, RWA = 4.5 log 10 normalized abundance, P < 0.01), and tet (M) (CONV = 5.4 log 10 normalized abundance, RWA = 5.8 log 10 normalized abundance, P < 0.01) were more abundant in RWA ground beef. Although these results suggest that antimicrobial use during U. S. cattle production does not increase human exposure to AMR via ground beef quantitative microbiological risk assessments are required for authoritative assessments regarding the human health impacts of antimicrobial uses during beef production.
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http://dx.doi.org/10.4315/JFP-20-376DOI Listing
December 2020

Greater decrements in neuromuscular function following interval compared to continuous eccentric cycling.

Eur J Sport Sci 2021 Jan 11:1-9. Epub 2021 Jan 11.

Faculty of Health and Life Sciences, Northumbria University, Newcastle-upon-Tyne, UK.

Our aim was to determine the demands and consequences of a single session of continuous (CONT) or interval (INT) eccentric cycling. Fourteen healthy males performed 'work-matched' CONT and INT eccentric cycling in a cross over design. Measures of maximal voluntary contraction (MVC), resting twitch force, voluntary activation (VA), muscle soreness and creatine kinase (CK) were taken at baseline, immediately post, and 24, 48 and 72 h post the first exercise bout. The second bout was used to characterise within session demands. Decreases in MVC (INT 19%, CONT 13%), twitch force (INT 31%, CONT 18%), and VA (INT 10%, CONT 6%) were observed immediately post session ( < 0.05). Reductions in twitch force were greater after INT ( < 0.05) and lasted 48 h. Muscle soreness was greater following INT, versus CONT ( < 0.05), although no differences in CK were observed. Metabolic demands (% of V̇O and [BLa]) were greater during INT vs. CONT (32 ± 6% 28 ± 6%;  < 0.001), [BLa] (1.0 ± 0.4 vs. 0.8 ± 0.2 mmol·L < 0.001) and RPE (12 ± 1 vs. 11 ± 1;  < 0.001), respectively. Total time under tension was 48% greater in CONT compared to INT ( < 0.001), whereas average torque (during exercise) was 40% greater during INT compared to CONT ( < 0.001). Interval eccentric cycling exacerbates muscle soreness, decrements in muscle function and lengthens recovery compared to a work matched continuous bout, which is attributable to increased force rather than time under tension.
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http://dx.doi.org/10.1080/17461391.2020.1858174DOI Listing
January 2021

Trends in artificial sweetener consumption: A 7-year wastewater-based epidemiology study in Queensland, Australia.

Sci Total Environ 2021 Feb 21;754:142438. Epub 2020 Sep 21.

Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, 20 Cornwall Street, Woolloongabba, 4102, Queensland, Australia. Electronic address:

A 7-year temporal trend study of artificial sweetener consumption was performed by determining per capital mass loads in 293 influent wastewater samples collected from a wastewater treatment plant in Australia between 2012 and 2018. Population-weighted per capita mass loads of the four detected artificial sweeteners ranged from 2.4 ± 0.8 mg d p for saccharin to 7.8 ± 2.0 mg d p for acesulfame over the study period. Negligible intra-week fluctuations were observed, however the consumption of acesulfame was seen to be significantly influenced by season with the highest consumption in summer. The consumption of sucralose and saccharin significantly increased with an annual increase rate of 10% and 6.0%. Cyclamate consumption declined over the same period with average annual decrease rate of 11%, which agrees with data from market surveys. Sucrose equivalence of total artificial sweeteners consumption showed an increase between 2012 and 2016, then decreased in 2018. This is the first long-term trend study of artificial sweetener consumption by wastewater analysis and highlights the feasibility to quantitatively measure artificial sweeter consumption over time.
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http://dx.doi.org/10.1016/j.scitotenv.2020.142438DOI Listing
February 2021

Intraday variability of indicator and pathogenic viruses in 1-h and 24-h composite wastewater samples: Implications for wastewater-based epidemiology.

Environ Res 2021 Feb 26;193:110531. Epub 2020 Nov 26.

United States Environmental Protection Agency, Office of Research and Development, 26W Martin Luther King Jr. Drive, Cincinnati, OH, 45268, USA.

We monitored the concentration of indicator viruses crAssphage and pepper mild mottle virus (PMMoV) and human pathogen adenovirus (HAdV) in influent from a wastewater treatment plant in Brisbane, Australia in 1-h and 24-h composite samples. Over three days of sampling, the mean concentration of crAssphage gene copies (GC)/mL in 24-h composite samples did not differ significantly (p = 0.72-0.92), while for PMMoV GC/mL (p value range: 0.0002-0.0321) and HAdV GC/mL (p value range: 0.0028-0.0068) significant differences in concentrations were observed on one day of sampling compared to the other two. For all three viruses, the variation observed in 1-h composite samples was greater than the variation observed in 24-h composite samples. For crAssphage, in 54.1% of 1-h composite samples, the concentration was less than that observed in 24-h composite samples; whereas for PMMoV and HAdV the concentration was less in 79.2 and 70.9% of 1-h composite samples, respectively, compared to the relevant 24-h composite samples. Similarly, the concentration of crAssphage in 1-h compared to 24-h composite samples did not differ (p = 0.1082) while the concentrations of PMMoV (p < 0.0001) and HAdV (p < 0.0001) in 1-h composite samples were significantly different from 24-h composite samples. These results suggest that 24-h composite samples offer increased analytical sensitivity and decreased variability compared to 1-h composite samples when monitoring wastewater, especially for pathogenic viruses with low infection rates within a community. Thus, for wastewater-based epidemiology applications, 24-h composite samples are less likely to produce false negative results and erroneous public health information.
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http://dx.doi.org/10.1016/j.envres.2020.110531DOI Listing
February 2021

Metagenomic Characterization of the Microbiome and Resistome of Retail Ground Beef Products.

Front Microbiol 2020 6;11:541972. Epub 2020 Nov 6.

Texas A&M University, VERO Program, Canyon, TX, United States.

Ground beef can be a reservoir for a variety of bacteria, including spoilage organisms, and pathogenic foodborne bacteria. These bacteria can exhibit antimicrobial resistance (AMR) which is a public health concern if resistance in pathogens leads to treatment failure in humans. Culture-dependent techniques are commonly used to study individual bacterial species, but these techniques are unable to describe the whole community of microbial species (microbiome) and the profile of AMR genes they carry (resistome), which is critical for getting a holistic perspective of AMR. The objective of this study was to characterize the microbiome and resistome of retail ground beef products labeled as coming from conventional or raised without antibiotics (RWA) production systems. Sixteen ground beef products were purchased from 6 retail grocery outlets in Fort Collins, CO, half of which were labeled as produced from cattle raised conventionally and half of products were from RWA production. Total DNA was extracted and isolated from each sample and subjected to 16S rRNA amplicon sequencing for microbiome characterization and target-enriched shotgun sequencing to characterize the resistome. Differences in the microbiome and resistome of RWA and conventional ground beef were analyzed using the R programming software. Our results suggest that the resistome and microbiome of retail ground beef products with RWA packaging labels do not differ from products that do not carry claims regarding antimicrobial drug exposures during cattle production. The resistome predominantly consisted of tetracycline resistance making up more than 90% of reads mapped to resistance gene accessions in our samples. Firmicutes and Proteobacteria predominated in the microbiome of all samples (69.6% and 29.0%, respectively), but Proteobacteria composed a higher proportion in ground beef from conventionally raised cattle. In addition, our results suggest that product management, such as packaging type, could exert a stronger influence on the microbiome than the resistome in consumer-ready products. Metagenomic analyses of ground beef is a promising tool to investigate community-wide shifts in retail ground beef. Importantly, however, results from metagenomic sequencing must be carefully considered in parallel with traditional methods to better characterize the risk of AMR in retail products.
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http://dx.doi.org/10.3389/fmicb.2020.541972DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7677504PMC
November 2020

Taking the Test: A Qualitative Analysis of Cultural and Contextual Factors Impacting Neuropsychological Assessment of Xhosa-Speaking South Africans.

Arch Clin Neuropsychol 2020 Nov 25. Epub 2020 Nov 25.

HIV Center for Clinical and Behavioral Studies, Columbia University and New York State Psychiatric Institute, New York City, NY, USA.

Objective: There is an urgent need to make neuropsychological (NP) testing more acceptable, accessible, and culturally salient, particularly for culturally, educationally, and linguistically diverse individuals from countries who may have little-to-no experience with NP testing. In settings with limited resources such as South Africa, unique cultural and contextual factors (e.g., structural inequality, poverty) may impact the experience of NP evaluation. Research in this area is limited and requires further exploration. This qualitative study explores the role of cultural and contextual factors that may impact the experience of NP evaluation in a sample of Xhosa-speaking South African adults. Participant interviews explored the context from which individuals arrived at the NP assessment (e.g., quality of education, understanding of cognitive disorders), and their experience of completing NP tests.

Method: This qualitative study used data from semistructured interviews to conduct a thematic analysis exploring contextual factors and the experience of completing NP tests for the first time among Xhosa-speaking South African adults (N = 22). Results: Although no participants had prior experience with NP testing, most found testing procedures acceptable. Most participants, however, reported a limited understanding of the purpose of NP testing and cognitive problems. Additionally, some participants reported perceptions and attitudes that could affect test performance, such as misinterpreting standard testing procedures (e.g., no feedback from the examiner, being stopped mid-task) as indicative of poor performance.

Conclusions: This study provided much needed exploration into unique cultural factors that may impact the experience of NP assessment in South Africa, which could bias test performance and interpretation, and may aid the field of cross-cultural NP in better serving culturally and linguistically diverse populations. In these countries, neuropsychologists may need to actively evaluate participants' understanding of NP testing to help foster optimal assessment conditions. They may also need to educate participants on possible causes of cognitive disorders.
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http://dx.doi.org/10.1093/arclin/acaa115DOI Listing
November 2020

Wastewater-based prevalence trends of gout in an Australian community over a period of 8 years.

Sci Total Environ 2021 Mar 9;759:143460. Epub 2020 Nov 9.

Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, Woolloongabba, Brisbane, QLD 4102, Australia.

Gout is a rheumatic arthritis disease which poses a health burden. Monitoring the prevalence of gout is key to reduce the community burden of gout disease and associated health costs. Allopurinol has been used as a first line gout preventive medication in Australia which is metabolised into oxypurinol and excreted in urine. Wastewater-based epidemiology (WBE) was applied to estimate temporal trends of gout prevalence in an Australian community over eight-years via the quantification of oxypurinol in wastewater. A total of 180 wastewater samples collected between 2012 and 2019 were analysed for oxypurinol to estimate allopurinol consumption in a community in South East Queensland, Australia. Annual gout prevalence was estimated by daily defined doses (DDD) consumed and ranged from 24 to 32 DDD/day/1000, an equivalent gout prevalence of 2.3 to 3.2% over the eight-year period. A statistically significant increase in allopurinol consumption was observed over the period (Slope = 0.094, p = 0.0001), equating to year-on-year increases in gout prevalence of 3.6% per year. To the best of our knowledge, this is the first long-term gout prevalence study using wastewater, adding epidemiological and public health insights in the gout research field.
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http://dx.doi.org/10.1016/j.scitotenv.2020.143460DOI Listing
March 2021

Release of Plastics to Australian Land from Biosolids End-Use.

Environ Sci Technol 2020 12 17;54(23):15132-15141. Epub 2020 Nov 17.

Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland 4102, Australia.

Plastics are contaminants of emerging concern that can enter the environment from multiple sources, including via land application of treated sewage sludge (biosolids). Biosolids samples collected from 82 wastewater treatment plants (WWTPs) across Australia and covering 34% of the population during census week in 2016 were quantitatively analyzed to estimate the release of seven common plastics. Quantitative analysis was performed by pressurized liquid extraction followed by double-shot microfurnace pyrolysis coupled to gas chromatography mass spectrometry. Ninety nine percent of the samples contained plastics (Σplastics) at concentrations of between 0.4 and 23.5 mg/g dry weight (median; 10.4 mg/g dry weight), while polycarbonate was not detected in any sample. Per-capita mass loads of plastics (Σplastics) released were between 8 and 877 g/person/year across all investigated WWTPs. Polyethylene was the predominant plastic detected, contributing to 69% of Σplastics. Based on the concentrations measured, it was projected that around 4700 metric tons (Mt) of plastics are released into the Australian environment through biosolids end-use each year, equating to approximately 200 g/person/year, which represents 0.13% of total plastics use in Australia. Of this, 3700 Mt of plastics are released to agricultural lands and 140 Mt to landscape topsoil. Our results provide a first quantitative per-capita mass loads and emission estimate of plastic types through biosolids end-use.
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http://dx.doi.org/10.1021/acs.est.0c05867DOI Listing
December 2020

Response to Comment on "Quantitative Analysis of Selected Plastics in High-Commercial-Value Australian Seafood by Pyrolysis Gas Chromatography Mass Spectrometry".

Environ Sci Technol 2020 12 15;54(23):15556-15557. Epub 2020 Nov 15.

Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland 4102, Australia.

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http://dx.doi.org/10.1021/acs.est.0c07097DOI Listing
December 2020

In vitro biotransformation and evaluation of potential transformation products of chlorinated paraffins by high resolution accurate mass spectrometry.

J Hazard Mater 2021 Mar 10;405:124245. Epub 2020 Oct 10.

Queensland Alliance for Environmental Health Science (QAEHS), The University of Queensland, 4102 Brisbane, Australia.

Chlorinated paraffins (CPs) are high production chemicals, which leads to their ubiquitous presence in the environment. To date, few studies have measured CPs in humans and typically at relatively low concentrations, despite indications that exposure may be high compared to various persistent organic pollutants. The aim of this study is to investigate the in vitro biotransformation of CPs by human liver fractions. We determined the changes of the CP concentrations after the enzymatic transformation with human liver microsomes using a two-tiered in vitro approach. CP concentrations decreased with human liver microsomes, with the decreases of 33-94% after incubating with different groups of enzymes for 2 h. The profiles of CP rapidly shifted after the incubation with human liver microsomes. In addition, the concentrations of CPs and the biotransformation products were tentatively measured using high-resolution mass spectrometric analysis, including very short CP (carbon chain length <10), alcohols, ketones, and carboxylic acids. C‒C bond cleavage is a potential transformation pathway for CPs, and ketones are potential products of CP biotransformation, especially for long-chain CPs (C). The ketone products may be investigated as CP exposure biomarker in biomonitoring studies.
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http://dx.doi.org/10.1016/j.jhazmat.2020.124245DOI Listing
March 2021

Surveillance of SARS-CoV-2 RNA in wastewater: Methods optimisation and quality control are crucial for generating reliable public health information.

Curr Opin Environ Sci Health 2020 Sep 30. Epub 2020 Sep 30.

Queensland Alliance for Environmental Health Sciences, The University of Queensland, Woolloongabba, QLD, 4102.

Monitoring for SARS-CoV-2 RNA in wastewater through the process of wastewater-based epidemiology (WBE) provides an additional surveillance tool, contributing to community-based screening and prevention efforts as these measurements have preceded disease cases in some instances. Numerous detections of SARS-CoV-2 RNA have been reported globally using various methods, demonstrating the technical feasibility of routine monitoring. However, in order to reliably interpret data produced from these efforts for informing public health interventions, additional quality control information and standardization in sampling design, sample processing, and data interpretation and reporting is needed. This review summarizes published studies of SARS-CoV-2 RNA detection in wastewater as well as available information regarding concentration, extraction, and detection methods. The review highlights areas for potential standardization including considerations related to sampling timing and frequency relative to peak fecal loading times; inclusion of appropriate information on sample volume collected; sample collection points; transport and storage conditions; sample concentration and processing; RNA extraction process and performance; effective volumes; PCR inhibition; process controls throughout sample collection and processing; PCR standard curve performance; and recovery efficiency testing. Researchers are recommended to follow the Minimum Information for Publication of Quantitative Real-Time PCR (MIQE) guidelines. Adhering to these recommendations will enable robust interpretation of wastewater monitoring results and improved inferences regarding the relationship between monitoring results and disease cases.
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http://dx.doi.org/10.1016/j.coesh.2020.09.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7544017PMC
September 2020

Physiological sex differences affect the integrative response to exercise: acute and chronic implications.

Exp Physiol 2020 12 17;105(12):2007-2021. Epub 2020 Oct 17.

Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK.

New Findings: What is the topic of this review? We review sex differences within physiological systems implicated in exercise performance; specifically, how they integrate to determine metabolic thresholds and fatigability. Thereafter, we discuss the implications that these sex differences might have for long-term adaptation to exercise. What advances does it highlight? The review collates evidence from recent physiological studies that have investigated sex as a biological variable, demonstrating that the physiological response to equivalent 'dosages' of exercise is not the same in males and females; thus, highlighting the need to research diversity in physiological responses to interventions.

Abstract: The anatomical and physiological differences between males and females are thought to determine differences in the limits of human performance. The notion of studying sex as a biological variable has recently been emphasized in the biosciences as a vital step in enhancing human health. In this review, we contend that the effects of biological sex on acute and chronic responses must be studied and accounted for when prescribing aerobic exercise, much like any intervention targeting the optimization of physiological function. Emerging evidence suggests that the response of physiological systems to exercise differs between males and females, potentially mediating the beneficial effects in healthy and clinical populations. We highlight evidence that integrative metabolic thresholds during exercise are influenced by phenotypical sex differences throughout many physiological systems. Furthermore, we discuss evidence that female skeletal muscle is more resistant to fatigue elicited by equivalent dosages of high-intensity exercise. How the different acute responses affect the long-term trainability of males and females is considered, with discussion about tailoring exercise to the characteristics of the individual presented within the context of biological sex. Finally, we highlight the influence of endogenous and exogenous sex hormones on physiological responses to exercise in females. Sex is one of many mediating influences on the outcomes of exercise, and with careful experimental designs, physiologists can advance the collective understanding of diversity in physiology and optimize outcomes for both sexes.
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http://dx.doi.org/10.1113/EP088548DOI Listing
December 2020

Sex differences in fatigability following exercise normalised to the power-duration relationship.

J Physiol 2020 12 26;598(24):5717-5737. Epub 2020 Sep 26.

Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK.

Key Points: Knee-extensors demonstrate greater fatigue resistance in females compared to males during single-limb and whole-body exercise. For single-limb exercise, the intensity-duration relationship is different between sexes, with females sustaining a greater relative intensity of exercise. This study established the power-duration relationship during cycling, then assessed fatigability during critical power-matched exercise within the heavy and severe intensity domains. When critical power and the curvature constant were expressed relative to maximal ramp test power, no sex difference was observed. No sex difference in time to task failure was observed in either trial. During heavy and severe intensity cycling, females experienced lesser muscle de-oxygenation. Following both trials, females experienced lesser reductions in knee-extensor contractile function, and following heavy intensity exercise, females experienced less reduction in voluntary activation. These data demonstrate that whilst the relative power-duration relationship is not different between males and females, the mechanisms of fatigability during critical power-matched exercise are mediated by sex.

Abstract: Due to morphological differences, females demonstrate greater fatigue resistance of locomotor muscle during single-limb and whole-body exercise modalities. Whilst females sustain a greater relative intensity of single-limb, isometric exercise than males, limited investigation has been performed during whole-body exercise. Accordingly, this study established the power-duration relationship during cycling in 18 trained participants (eight females). Subsequently, constant-load exercise was performed at critical power (CP)-matched intensities within the heavy and severe domains, with the mechanisms of fatigability assessed via non-invasive neurostimulation, near-infrared spectroscopy and pulmonary gas exchange during and following exercise. Relative CP (72 ± 5 vs. 74 ± 2% P , P = 0.210) and curvature constant (51 ± 11 vs. 52 ± 10 J P , P = 0.733) of the power-duration relationship were similar between males and females. Subsequent heavy (P = 0.758) and severe intensity (P = 0.645) exercise time to task failures were not different between sexes. However, females experienced lesser reductions in contractile function at task failure (P ≤ 0.020), and greater vastus lateralis oxygenation (P ≤ 0.039) during both trials. Reductions in voluntary activation occurred following both trials (P < 0.001), but were less in females following the heavy trial (P = 0.036). Furthermore, during the heavy intensity trial only, corticospinal excitability was reduced at the cortical (P = 0.020) and spinal (P = 0.036) levels, but these reductions were not sex-dependent. Other than a lower respiratory exchange ratio in the heavy trial for females (P = 0.039), no gas exchange variables differed between sexes (P ≥ 0.052). Collectively, these data demonstrate that whilst the relative power-duration relationship is not different between males and females, the mechanisms of fatigability during CP-matched exercise above and below CP are mediated by sex.
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http://dx.doi.org/10.1113/JP280031DOI Listing
December 2020