Modular hip exoskeleton improves walking function and reduces sedentary time in community-dwelling older adults

Numerous studies showed that postural balance improves through light touch on a stable surface highlighting the importance of haptic information, seemingly downplaying the mechanical contributions of the support. The present study examined the mechanical effects of canes for assisting balance in healthy individuals challenged by standing on a beam. Sixteen participants supported themselves with two canes, one in each hand, and applied minimal, preferred, or maximum force onto the canes. They positioned the canes in the frontal plane or in a tripod configuration. Statistical analysis used a linear mixed model to evaluate the effects on the center of pressure and the center of mass. The canes significantly reduced the variability of the center of pressure and the center of mass to the same level as when standing on the ground. Increasing the exerted force beyond the preferred level yielded no further benefits, although in the preferred force condition, participants exploited the altered mechanics by resting their arms on the canes. The tripod configuration allowed for larger variability of the center of pressure in the task-irrelevant anterior–posterior dimension. High forces had a destabilizing effect on the canes: the displacement of the hand on the cane handle increased with the force. Given this static instability, these results show that using canes can provide not only mechanical benefits but also challenges. From a control perspective, effort can be reduced by resting the arms on the canes and by channeling noise in the task-irrelevant dimensions. However, larger forces exerted onto the canes can also have destabilizing effects and the instability of the canes needs to be counteracted, possibly by arm and shoulder stiffness. Insights into the variety of mechanical effects is important for the design of canes and the instructions of how to use them.     

基于PERK-eIF2α-CHOP通路调控巨噬细胞胆固醇稳态及冠心康含药血清干预机制研究＊

目的 观察具有益气化痰活血作用的冠心康对人单核/巨噬细胞株THP-1细胞PERK-eIF2α信号通路及相关活化转录因子（ATF）和C/EBP同源转录因子（CHOP）的影响，探究冠心康对胆固醇在巨噬细胞内质网中的代谢稳态调节及作为“脂毒”流出后异常沉积的相关作用。方法 采用100 ng·mL^-1 PMA及80 μg·mL^-1氧化低密度脂蛋白诱导THP-1细胞株，构建巨噬细胞模型，并随机分为模型组、冠心康组、辛伐他汀组、正常组。分别采用10%小牛血清及含药血清干预模型细胞72 h后收集细胞。HE染色观察巨噬细胞病理形态变化，同时进行胆固醇及脂滴含量测定。分别采用Real-time PCR及Western blot法检测各组细胞PERK、eIF2α、ATF、CHOP mRNA及蛋白的表达。结果 HE染色观察到模型组细胞内呈现较多红色脂滴，经胆固醇含量测定，明显高于正常组，脂滴含量测定与前者一致（P<0.01）。模型组细胞ATF、CHOP基因表达水平均显著升高（P<0.01）。与模型组比较，冠心康组和辛伐他汀组细胞ATF、CHOP基因表达水平均显著降低（P<0.01）。PERK磷酸化以及CHOP蛋白表达水平在冠心康和辛伐他汀干预组表现为显著下调，与模型组比较，差异具有统计学意义（P<0.05）。结论 冠心康可能通过调控PERK-eIF2α-CHOP通路相关基因及蛋白，减少泡沫细胞形成，从而减轻内质网应激，维持细胞内胆固醇稳态，减少细胞内胆固醇沉积。     

Correction to: “Living with COVID”—implications for immunosuppressed and immunocompromised

Clinical Rheumatology -     

Calculation of the Biological Efficiency of the Proton Component from 14.8 MeV Neutron Irradiation in Computational Biology with Help of Video Cards

Bulletin of Experimental Biology and Medicine - Fast neutron therapy, which previously has demonstrated effective results, but along with a large number of complications, can again be considered a...     

Quantitative Assessment and Predicting the Effects of Soil Pollutants on Herbaceous Biomass Production in Reserved Forests

Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Heavy metal concentrations in surface soils of Reserved Forests (RFs) have a significant impact on...     

定量分析对常规超声联合超声造影定性误诊甲状腺结节的诊断价值

摘要：目的：探讨超声造影（CEUS）定量分析对常规超声联合CEUS定性诊断误诊为恶性的甲状腺结节与甲状腺乳头状癌的鉴别诊断价值。方法：选取2018年7月至2021年11月在我院超声科行甲状腺常规超声及CEUS检查，术前联合超声诊断为恶性（C-TIRADS≥4b 或 CEUS 表现为低增强和快速消退任一征像）而病理为良性的35位患者共35个结节为研究组；选择同期联合超声诊断与病理一致的甲状腺乳头状癌患者47例做为对照组。分析常规超声及CEUS特征，并将结节整体、中央部、边缘部及邻近正常甲状腺实质作为感兴趣区分别绘制时间-强度曲线（TIC）进行定量分析，比较两组结节各定量参数之间的差异。结果：研究组整体相对上升时间（△RT）以0.45为截断值，诊断恶性结节的敏感度为97.9%，特异度为85.7%，受试者工作（ROC）曲线下面积为0.96；研究组中央区△RT以0.55为截断值，诊断恶性结节的敏感度为95.7%，特异度为82.9%，ROC曲线下面积为0.87；研究组边缘区△RT以0.25为截断值，诊断恶性结节的敏感度为89.4%，特异度为77.1%，ROC曲线下面积为0.89。结论：CEUS定量分析在常规超声联合CEUS定性误诊甲状腺结节的诊断中具有一定的鉴别诊断价值。