A case of sudden cardiac death due to mitochondrial disease

A 25-year-old, emaciated man without medical treatment was found to have died suddenly at home by his mother. At autopsy, there were no injuries to his body, but significant circulatory insufficiency was observed. Electron microscopy revealed abnormal mitochondria in cells of the cardiac conduction system. The conduction system was filled with mitochondrial size abnormalities and mitochondrial cristae abnormalities. No notable abnormal findings were observed in other organs. Genetic examination of the blood revealed the mitochondrial pathogenetic variant m.3243A>G. Epileptic seizures, diabetic ketoacidosis, and hyperosmolar hyperglycemic state were unlikely to be the cause of sudden death. The cause of death was diagnosed as arrhythmia possibly induced by the failure of the cardiac conduction system due to mitochondrial disease. This is a rare case of sudden death caused by an accumulation of abnormal mitochondria in the cardiac conduction system.     

携带同源重组修复相关基因突变的消化道肿瘤的临床特点

目的:探讨消化道肿瘤中同源重组修复相关基因(homologous recombination repair related gene，HRR)突变的发生情况及临床意义。方法:共92例消化道肿瘤患者，79例患者进行了血液标本HRR检测，53例患者进行了组织标本HRR检测，40例患者同时行血液和组织的HRR基因检测，收集患者基因检测结果及临床相关资料。结果:在79例患者血液标本检测中发现10例（12.6%）有临床意义HRR突变，在53例患者组织标本检测中发现9例（17.0%）有临床意义HRR突变。40例同时行血液和组织的HRR基因检测患者中常见的有临床意义HRR突变为CDK12突变4例（10.0%）、ATM突变3例（7.5%）、BRCA1突变2例（5.0%）。13例有临床意义HRR突变患者中常见共存突变为TP53突变10例（76.9%）、APC突变5例（38.5%）、PIK3CA突变4例（30.8%）。40例患者中13例患者血液和/或组织中有临床意义HRR突变，27例患者血液和组织中均无任何临床意义HRR突变且两组相比，有临床意义HRR突变组肿瘤突变负荷（tumor mutational burden，TMB）为6.17(2.24～11.52)，而未携带HRR突变组TMB为0.4(0～3.75)，差异有统计学意义（P＜0.05）。40例患者组织检测中7例HRR有临床意义的突变，33例无HRR突变，血液检测中10例HRR有临床意义的突变，30例无HRR突变，一致性检验的Kappa值为0.333（P=0.031）。结论:携带有临床意义HRR突变的消化道肿瘤患者TMB更高，血液和组织检测HRR突变有较好的一致性。     

Effect of gender on the reliability of COVID-19 rapid antigen test among elderly

Defining con-founders that affect the reliability of diagnostic tests for coronavirus disease 2019 is vital to breaking the chain of infection. The elderly population is a higher risk group for the emerging virus. However, gender seems to exert a critical role in modifying the infection risk among women owing to hormonal changes. The menopause transition is an exceptional period for older women where the protective and immunomodulatory effects of the estrogen hormone are lost. Accordingly, attention should be given to postmenopausal women since they will have an increased risk compared to their pre-menopausal peers.     

Understanding congenital vertical talus

Congenital vertical talus (CVT) is a rare foot deformity that presents with a rigid flat foot at birth. CVT can present as an isolated abnormality in the newborn, however in at least 50% of cases in association with other conditions. Full neuro-axial imaging is essential to detect any associated neurologic problems. Radiographs of the foot, including forced plantar and dorsiflexion laterals, are diagnostic. Gold standard modern treatment uses the Dobbs method of serial manipulation and casting with minimally-invasive stabilization of the talonavicular joint and Achilles tendon tenotomy.     

Evaluation of unsupervised 30-second chair stand test performance assessed by wearable sensors to predict fall status in multiple sclerosis

BackgroundOne in two people with multiple sclerosis (PwMS) will fall in a three-month period. Predicting which patients will fall remains a challenge for clinicians. Standardized functional assessments provide insight into balance deficits and fall risk but their use has been limited to supervised visits.Research questionThe study aim was to characterize unsupervised 30-second chair stand test (30CST) performance using accelerometer-derived metrics and assess its ability to classify fall status in PwMS compared to supervised 30CST.MethodsThirty-seven PwMS (21 fallers) performed instrumented supervised and unsupervised 30CSTs with a single wearable sensor on the thigh. In unsupervised conditions, participants performed bi-hourly 30CSTs and rated their balance confidence and fatigue over 48-hours. ROC analysis was used to classify fall status for 30CST performance.ResultsNon-fallers (p = 0.02) but not fallers (p = 0.23) differed in their average unsupervised 30CST performance (repetitions) compared to their supervised performance. The unsupervised maximum number of 30CST repetitions performed optimized ROC classification AUC (0.79), accuracy (78.4%) and specificity (90.0%) for fall status with an optimal cutoff of 17 repetitions.SignificanceBrief durations of instrumented unsupervised monitoring as an adjunct to routine clinical assessments could improve the ability for predicting fall risk and fluctuations in functional mobility in PwMS.