Citations

Abstract Background This study simulates how assay-specific bias influences the diagnostic performance of 0/1-h accelerated diagnostic protocols (ADPs) for 3 different high-sensitivity cardiac troponin (hs-cTn) assays. Methods We included 1493 patients presenting with chest pain. hs-cTnT (Roche Diagnostics), hs-cTnI from Abbott Diagnostics (hs-cTnI-A), and Siemens Healthineers (hs-cTnI-S) were measured at admission. The absolute total error observed in a state-of-the-art EQA study were added to the admission concentrations, producing 6 new variables being adjusted for maximum possible bias (if analytical variation is 0) (+biasmean, +biasmax95%CI, +biasmin95%CI, −biasmean, −biasmax95%CI, −biasmin95%CI). The influence of this “worst-case scenario” bias was compared after calculating sensitivity, specificity, negative and positive predictive values, and rule-out proportion for 30-day myocardial infarction or death for the observed and bias-adjusted hs-cTn concentrations. Results For 0-h rule-out, hs-cTnI-S and hs-cTnT had a sensitivity of >99.0%, compared to 97.7% for hs-cTnI-A. After adding the bias, sensitivity was unchanged for hs-cTnI-S (99.5%), but lower for hs-cTnT (95.5%), and hs-cTnI-A (96.2%). For the 0-/1-h algorithm, adding bias reduced sensitivity to 95.5% for hs-cTnT, while both hs-cTnI algorithms were unchanged (100.0%). Rule-out proportions for 0 h ranged from 0% to 60.0% for hs-cTnT, 28.2%–62.7% for hs-cTnI-A, and 3.5%–35.5% for hs-cTnI-S. For the 0-/1-h algorithm, ranges were 57.7%–75.8% (hs-cTnT), 52.8%–67.5% (hs-cTnI-A), and 45.7%–61.2% (hs-cTnI-S), Conclusion Analytical bias of hs-cTn assays affects the clinical rule-out rate of the 0/1-h ADPs more than the diagnostic sensitivity. Bias may have a greater influence on the proportion of patients requiring hospital admission and may contribute to the heterogeneity of the reported rule-out rates of current ADPs. ClinicalTrials.gov Registration Number: NCT02620202

Abstract Background: Black or African Americans (AA) with Parkinson’s disease (PD) are underrepresented in both care and research and experience significant health disparities. The existing literature provides limited guidance on how to enhance the engagement of AA individuals in PD care and research, particularly from the perspectives of AA patients, care partners, and healthcare providers. This project aimed to (1) describe the use of Community Engagement (CE) Studios as a community-engaged research approach to inform culturally appropriate and inclusive research and (2) examine factors influencing AA engagement in PD-related activities. Methods: We conducted three CE Studios: one with AA with PD and care partners (N = 6), one with healthcare providers of AA with PD (N = 8), and one with AA with PD, care partners, and healthcare providers (N = 4). Results: The CE Studios informed the design (e.g., cultural appropriateness) and conduct (e.g., accessibility) of the planned PD project, as well as identifying stakeholders to engage with, improving alignment between research and the AA community. We highlighted the importance of multifaceted factors, including environmental (e.g., segregation), biological (e.g., symptoms), sociocultural (e.g., not being invited), and behavioral (e.g., empowerment) domains, which influence AA engagement. Conclusions: The CE Studios method is a feasible and useful approach for understanding the perspectives of AA in PD. It is possible to conduct an in-depth exploration of community perspectives by synthesizing comprehensive analyses and leveraging additional frameworks. These efforts include identifying barriers to engagement, recognizing locally relevant individuals, and refining PD-related care to enhance cultural appropriateness.

This study presents the first in vivo intraoperative measurement of the kinetic properties of spastic human muscle. Despite slower relaxation in spastic biceps, the force-frequency relationship was similar to that of the healthy gracilis muscle. This suggests that spasticity does not substantially alter frequency-dependent force summation, possibly due to similar fiber-type compositions and limited changes in calcium handling or myosin isoforms in human spastic muscle.

Cervical arthrography was performed on 13 patients with putative cervical facet symptoms. Under fluoroscopic control, injection of radiopaque dye, local anesthetic, and depot steroid into the affected joint capsule was performed without complication. Eleven of the 13 patients had partial to complete pain relief during the 2-week to 6-month followup period.

ABSTRACTAimTo report a novel case of biopsy‐proven, mass spectrometry‐confirmed, wild‐type transthyretin amyloidosis (ATTRwt) in nerve.MethodsThe patient was identified and evaluated in the peripheral nerve clinic. Our nerve laboratory's pathology database and the literature were searched for prior evidence of pathologically confirmed cases of ATTRwt.ResultsA 94‐year‐old man with a history of lumbar spinal stenosis presented to the neurology clinic with subacute‐on‐chronic progressive, upper limb predominant weakness along with numbness and tingling paresthesia. Electromyography (EMG) revealed multiple mononeuropathies involving the right median nerve at the wrist, right ulnar nerve, and right distal radial nerve superimposed upon an axonal predominant peripheral neuropathy along with multilevel lumbosacral radiculopathies. Extensive serology for causes of neuropathy and multiple mononeuropathies returned unremarkable. A diagnostic right superficial radial nerve biopsy was performed and showed congophilic material within a small epineurial vessel wall in the nerve tissue. Amyloid typing by mass spectrometry was performed and revealed ATTRwt. TTR gene sequencing returned normal. The patient was diagnosed with ATTRwt neuropathy and started on diflunisal therapy for neuropathy treatment.ConclusionThis case confirms the presence of ATTRwt deposition directly in nerve tissue as the likely cause of the patient's large fiber and multiple mononeuropathies, expanding our current understanding of ATTRwt‐associated disease. Proving the direct association of ATTRwt and neuropathy may open up amyloid‐specific treatments for this disease.

ABSTRACT Aims X‐linked McLeod neuroacanthocytosis syndrome (MLS) is a rare neurodegenerative disorder characterised by the presence of red blood cell acanthocytosis and a chorea syndrome. Analogous to Huntington's disease (HD), MLS displays cognitive and behavioural symptoms besides the progressive movement disorder. This study aimed to describe the neuropathology of MLS in the largest case series to date. Methods Clinical data were collected, and neuropathological assessments were performed on eight male MLS patients originating from Finland, New Zealand, Switzerland, Scotland and the United States. Results Macroscopic data were available from six patients, with five showing atrophy of the basal ganglia, which was more pronounced in the caudate nucleus and to a lesser extent in the putamen and pallidum. Histology revealed neuronal loss and accompanying gliosis in the basal ganglia of all patients. The extent of these alterations varied widely, with a decreasing gradient of severity from the caudate nucleus to the putamen and the pallidum, mirroring the macroscopic findings. In addition, we detected intraneuronal vacuoles in the striatum in half of the patients. Conclusions MLS neuropathology is characterised macroscopically by atrophy and microscopically by neuronal loss and gliosis of the basal ganglia, with a decreasing gradient of severity from the caudate nucleus, the putamen to the pallidum. Analogous to the grading system for HD, we propose a neuropathological grading system for MLS based on the current observations in the largest MLS cohort examined to date. Standardised criteria are crucial for neuropathological assessment of this extremely rare disease.

Abstract Background Physical activity (PA) is an established protective factor for colorectal cancer (CRC), but it is unclear if genetic variants modify this effect. To investigate this possibility, we conducted a genome-wide gene–PA interaction analysis. Methods Using logistic regression and two-step and joint tests, we analyzed interactions between common genetic variants across the genome and PA in relation to CRC risk. Self-reported PA levels were categorized as active (≥ 8.75 MET-h/wk) vs. inactive (< 8.75 MET-h/wk) and as study- and sex-specific quartiles of activity. Results PA had an overall protective effect on CRC (OR [active vs. inactive] = 0.85; 95%CI = 0.81–0.90). The two-step GxE method identified an interaction between rs4779584, an intergenic variant near the GREM1 and SCG5 genes, and PA for CRC risk (p-interaction = 2.6×10 − 8 ). Stratification by genotype at this locus showed a significant reduction in CRC risk by 20% in active vs. inactive participants with the CC genotype (OR = 0.80; 95%CI = 0.75–0.85), but no significant PA–CRC association among CT or TT carriers. When PA was modeled as quartiles, the 1-d.f. GxE test identified that rs56906466, an intergenic variant near the KCNG1 gene, modified the association between PA and CRC (p-interaction = 3.5×10 − 8 ). Stratification at this locus showed that increase in PA (highest vs. lowest quartile) was associated with a lower CRC risk solely among TT carriers (OR = 0.77; 95%CI = 0.72–0.82). Conclusions In summary, we identified two genetic variants that modified the association between PA and CRC risk. One of them, related to GREM1 and SCG5 , suggests that the bone morphogenetic protein (BMP)-related, inflammatory, and/or insulin signaling pathways may be associated with the protective influence of PA on colorectal carcinogenesis.