Johnson Andrew

Western University

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Michael Robinson

Western University

Fischer Lisa

Fowler Kennedy Sport Medicine Clinic

Acikoglu Merve

United States Virgin Islands Department of Health

Sheehan Vivien

Williams L. Keoki

David Tirschwell

University of Washington

D Barfoot Timothy

Agruicultural Research Institute

Weimin Chen

Kunming University

S Martin Kevin

Naveen Kumar Chaundhary

National Forensic Sciences University

Cooperative Institutions

Agruicultural Research Institute

528

United States Virgin Islands Department of Health

Boston University

University of Washington

Framingham Heart Study

The University of Texas Health Science Center at Houston

University of Mississippi Medical Center

Jackson Memorial Hospital

University of California, Davis

Johns Hopkins University

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Whole genome sequence analyses of brain imaging measures in the Framingham Study

Neurology (2017)

Chloé Sarnowski Claudia L. Satizábal Charles DeCarli Achilleas Pitsillides L. Adrienne Cupples

We sought to identify rare variants influencing brain imaging phenotypes in the Framingham Heart Study by performing whole genome sequence association analyses within the Trans-Omics for Precision Medicine Program.We performed association analyses of cerebral and hippocampal volumes and white matter hyperintensity (WMH) in up to 2,180 individuals by testing the association of rank-normalized residuals from mixed-effect linear regression models adjusted for sex, age, and total intracranial volume with individual variants while accounting for familial relatedness. We conducted gene-based tests for rare variants using (1) a sliding-window approach, (2) a selection of functional exonic variants, or (3) all variants.We detected new loci in 1p21 for cerebral volume (minor allele frequency [MAF] 0.005, p = 10-8) and in 16q23 for hippocampal volume (MAF 0.05, p = 2.7 × 10-8). Previously identified associations in 12q24 for hippocampal volume (rs7294919, p = 4.4 × 10-4) and in 17q25 for WMH (rs7214628, p = 2.0 × 10-3) were confirmed. Gene-based tests detected associations (p ≤ 2.3 × 10-6) in new loci for cerebral (5q13, 8p12, 9q31, 13q12-q13, 15q24, 17q12, 19q13) and hippocampal volumes (2p12) and WMH (3q13, 4p15) including Alzheimer disease- (UNC5D) and Parkinson disease-associated genes (GBA). Pathway analyses evidenced enrichment of associated genes in immunity, inflammation, and Alzheimer disease and Parkinson disease pathways.Whole genome sequence-wide search reveals intriguing new loci associated with brain measures. Replication of novel loci is needed to confirm these findings.

Framingham Heart Study

Genome-wide Association Study

10.1212/wnl.0000000000004820

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Citations (39)

Author index

Journal of ISAKOS Joint Disorders & Orthopaedic Sports Medicine (2021)

Aasen Baksaas Aburish Zein Ackermann Jakob Aga Cathrine Gabriel Agar

10.1136/jisakos-2021-congress.authorindex

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6.9 Two symptoms to triage acute concussions: using decision tree modeling to predict prolonged recovery following concussion

Michael Robinson M Heather Johnson Andrew Fischer Lisa

Objective

The objective was to examine the 22 variables from the Sport Concussion Assessment Tool's 5^th Edition (SCAT5) Symptom Evaluation using a decision tree analysis to identify those most likely to predict prolonged recovery following sport-related concussion.

Design

Cross sectional.

Setting

Single site – Primary care.

Participants

273 patients (52% male, mean age 21 ± 7.6 years) initially assessed by either an emergency medicine or sport medicine physician within 14 days of concussion (mean 6 ± 4 days).

Interventions (or Assessment of Risk Factors)

22 symptoms from the Sport Concussion Assessment Tool 5th Edition

Outcome Measures

A decision tree analysis was performed using RStudio and the R package rpart. The decision tree was generated using a complexity parameter of 0.045, post-hoc pruning was conducted with rpart and the package carat was used to assess the final decision tree's accuracy, sensitivity and specificity.

Main Results

Of the 22 variables, only 2 contributed towards the predictive splits: Feeling like 'in a fog', and Sadness. The confusion matrix yielded a statistically significant accuracy of 0.7636 (p-Value [Acc > NIR]: 0.00009678), sensitivity of 0.6429, specificity of 0.8889, positive predictive value of 0.8571 and a negative predictive value of 0.7059.

Conclusions

Decision tree analysis yielded a statistically significant decision tree model which can be used clinically to identify patients at initial presentation who are at a higher risk of having prolonged symptoms lasting 28 days or more post-concussion.

Triage

10.1136/bjsports-2023-concussion.85

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北極繁殖海鳥の繁殖形質の季節的減少により明らかにされた生活史トレードオフ【Powered by NICT】

Journal of Avian Biology (2018)

L Weiser Emily C Brown Stephen B Lanctot Richard Gates H. River F Abraham Kenneth

Source

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Citations (1)

Author Index

Acikoglu Merve Hussein Alghazo Oleg Alienin Paul Anand Ana Rita

10.1109/isdfs55398.2022.9800825

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3.15 Measurement properties of the adult version of the sport concussion assessment tool 5th edition symptom evaluation using Rasch analysis

Michael Robinson Fischer Lisa Johnson Andrew

Objective

To evaluate the psychometric and measurement properties of the 5^th edition of the Sport Concussion Assessment Tool (SCAT5) Symptom Evaluation using Rasch analysis.

Design

Cross sectional study using Rasch analysis.

Setting

Single Site – Primary Care Setting.

Participants

A total of 284 participants who were still experiencing concussion symptoms were included (130 males, 154 females, mean age 20.8 ±10.4). Participants were 13 years of age or older, with a diagnosis of concussion from a primary care physician.

Interventions

The SCAT5 symptom evaluation was administered to patients as a component of their routine clinical encounter and the presence and severity of each of the 22 symptoms was included in the analysis.

Outcome Measures

Rasch analysis was performed using RUMM 2030 to assess the SCAT5 symptom evaluation for overall fit, response scaling, individual item fit, differential item functioning, local dependency, unidimensionality and reliability.

Main Results

The SCAT5 symptom evaluation demonstrated an acceptable fit to the Rasch model, exhibited high reliability and was able to differentiate between at least 4 levels of patients. Nonetheless, serious psychometric issues were identified. Response dependencies were identified between 15 pairs of items. Further, 11 items were found to have sex-linked response biases, and the overall scale was found to be multidimensional (suggesting that the scale is measuring multiple constructs).

Conclusions

The Rasch model appears unsuitable for psychometric evaluation of the SCAT5 symptom checklist. Methods for addressing these issues will be discussed in the context of leveraging this analysis to create a more reliable and valid tool.

Differential item functioning

10.1136/bjsports-2023-concussion.55

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Regulation of blastocyst formation

Frontiers in bioscience (2001)

Johnson Andrew

Preimplantation or pre-attachment development encompasses the "free"-living period of mammalian embryogenesis, which directs development of the zygote through to the blastocyst stage. Blastocyst formation is essential for implantation, establishment of pregnancy and is a principal determinant of embryo quality prior to embryo transfer. Cavitation (blastocyst formation) is driven by the expression of specific sets of gene products that direct the acquisition of cell polarity within the trophectoderm, which is both the first epithelium of development and the outer cell layer encircling the inner cell mass of the blastocyst. Critical gene families controlling these events include: the E-cadherin-catenin cell adhesion family, the tight junction gene family, the Na/K-ATPase gene family and perhaps the aquaporin gene family. This review will update the roles of each of these gene families in trophectoderm differentiation and blastocyst formation. The current principal hypothesis under investigation is that blastocyst formation is mediated by a trans-trophectoderm ion gradient(s) established, in part, by Na/K-ATPase, which drives the movement of water through aquaporins (AQPs) across the epithelium into the extracellular space of the blastocyst to form the fluid-filled blastocoel. The trophectoderm tight junctional permeability seal regulates the leakage of blastocoel fluid, and also assists in the maintenance of a polarized Na/K-ATPase distribution to the basolateral plasma membrane domain of the mural trophectoderm. The cell-to-cell adhesion provided by the E-cadherin-catenin gene families is required for the establishment of the tight junction seal and the maintenance of the polarized Na/K-ATPase distribution. Blastocyst formation is therefore directly linked with trophectoderm cell differentiation, which arises through fundamental cell biological processes that are associated with the establishment of cell polarity.

Blastocoel

Inner cell mass

Cell polarity

Adherens junction

10.2741/watson

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Citations (200)