Extended foot-ankle musculoskeletal models for application in movement analysis

Multibody simulations of human motion require representative models of the anatomical structures. A model that captures the complexity of the foot is still lacking. In the present work, two detailed 3D multibody foot-ankle models generated based on CT scans using a semi-automatic tool are described. The proposed models consists of five rigid segments (talus, calcaneus, midfoot, forefoot and toes), connected by five joints (ankle, subtalar, midtarsal, tarsometatarsal and metatarsophalangeal), one with 15DOF and the other with 8DOF. The calculated kinematics of both models were evaluated using gait trials and compared against literature, both presenting realistic results. An inverse dynamic analysis was performed for the 8DOF model, again presenting feasible dynamic results.     

口蹄疫病毒外源序列插入位点的研究进展

伴随着对口蹄疫病毒(FMDV)蛋白结构功能的深入研究,发现FMDV能够表达外源基因片段。通过对FMDV的基因进行改造和修饰研究,进而实现了不同应用目的,如提高病毒滴度、引入标记、提高免疫应答、降低致病性等。文中主要从FMDV接受外源基因插入位点角度来介绍现阶段关于FMDV表达外源基因相关进展。     

糖尿病足治疗新进展

糖尿病足溃烂是糖尿病的常见慢性并发症,以高发生率、高致残率、经济负担重,治疗时间长及高死亡率严重影响病人的生活质量甚至威胁生命,我国糖尿病协会于2010年11月14公布我国糖尿病的患病者已达9240万,除此之外糖尿病前期患者已达1.482亿。而在糖尿病患者中糖尿病足的发病率达到1.7%-11.9%;糖尿病患者中有15%的患者一生中有患糖尿病足的倾向,因此对于糖尿病足的治疗显得尤为重要,本文从糖尿病足的病因、机制,微环境变化着手,重点阐述糖尿病足传统的中西医疗法及目前的手术、介入及干细胞治疗方法的近况,旨在探讨各种方法的优点和不足及可开拓的空间,为进一步治疗糖尿病足提供一定的理论依据,为糖尿病足新方法的研究提供一些新的思维方式。     

An in vitro and finite element study of load redistribution in the midfoot

A good knowledge of midfoot biomechanics is important in understanding the biomechanics of the entire foot,but it has never been investigated thoroughly in the literature.This study carried out in vitro experiments and finite element analysis to investigate the midfoot biomechanics.A foot-ankle finite element model simulating the mid-stance phase of the normal gait was developed and the model validated in in vitro experimental tests.Experiments used seven in vitro samples of fresh human cadavers.The simulation found that the first principal stress peaks of all midfoot bones occurred at the navicular bone and that the tensile force of the spring ligament was greater than that of any other ligament.The experiments showed that the longitudinal strain acting on the medial cuneiform bone was-26.2±10.8μ-strain,and the navicular strain was-240.0±169.1μ-strain along the longitudinal direction and 65.1±25.8μ-strain along the transverse direction.The anatomical position and the spring ligament both result in higher shear stress in the navicular bone.The load from the ankle joint to five branches of the forefoot is redistributed among the cuneiforms and cuboid bones.Further studies on the mechanism of loading redistribution will be helpful in understanding the biomechanics of the entire foot.     

Infection with the fungal endophyte Epichloë festucae may alter the allelopathic potential of red fescue

Red fescue (Festuca rubra) is a perennial grass used as both forage and turfgrass. Asymptomatic plants of this species are systemically infected by the fungal endophyte Epichloë festucae, which has a beneficial effect on the infected plants. The aim of this study was to determine the effect of the endophyte Epichloë festucae on the allelopathic potential of F. rubra against four associated pasture species that are also considered as weeds in lawns, Trifolium pratense, Trifolium repens, Lotus corniculatus and Plantago lanceolata. Two experiments were designed to evaluate the allelopathic effect of extracts from the roots and leaves of endophyte‐infected (E+) and non‐infected (E?) plants on the germination and seedling growth of the four target species. Regardless of the endophyte status of the host plant, leaf extracts elicited a stronger reduction in germination and seedling growth than root extracts. Extracts from E+ plants reduced the speed of germination index of Trifolium spp. to a greater extent than those from E? plants. Radicle length of the target species was the parameter most affected by the presence of the endophyte in F. rubra. Root extracts from E+ plants had a greater inhibitory effect on the radicle growth of the target species than did root extracts from E? plants. A greater concentration in total phenolic compounds was found in the roots of E+ plants than of E?; however, this difference was not observed in the leaves. Thus, the allelopathic potential of F. rubra is altered in infected plants.     

足踝骨肿瘤切除后采用腓肠神经营养血管皮瓣术的修复效果及对运动功能的影响

摘要 目的：探讨足踝骨肿瘤切除后采用腓肠神经营养血管皮瓣术的修复效果及对运动功能的影响。方法：选取我院2013~2019年收治的足踝骨肿瘤切除患者83例,应用随机分组法将其分为研究组41例和对照组42例。对照组患者应用以往清创换药的保守修复方法,研究组患者应用腓肠神经营养血管皮瓣术修复方法,对比两组患者的治疗总有效率与致残率、住院费用、住院时间以及治疗前后运动功能的变化。结果：治疗后,研究组的总有效率为90.24%,显著高于对照组(64.29%,P＜0.05);两组患者住院花费比较差异无统计学意义(P＞0.05);研究组患者的住院天数上明显短于对照组(P＜0.05);研究组患者的致残率为2.44%,明显低于对照组(16.67%,P＜0.05);研究组患者修复后的Fugl-Meyer下肢运动功能评定(Fugl-Meyer assessment,FMA)和Berg平衡量表(Berg Balance Scale,BBS)评分均明显高于对照组(P＜0.05)。结论：腓肠神经营养血管皮瓣术修复术较清创换药的保守修复方法可以更有效修复足踝骨肿瘤广泛切除术后患者足踝部的创伤面,改善患者运动功能,且手术方法相对简单,安全性更高。     

利巴韦林喷雾剂联合小儿豉翘清热颗粒对手足口病患儿外周血T淋巴细胞亚群、血清免疫球蛋白指标和炎性因子的影响

摘要 目的：探讨利巴韦林喷雾剂联合小儿豉翘清热颗粒对手足口病（HFMD）患儿外周血T淋巴细胞亚群、血清免疫球蛋白指标和炎性因子的影响。方法：选择2019年8月至2022年6月期间我院收治的HFMD患儿90例作为考察对象。按照双色球法将患儿分为对照组和研究组,各为45例。在常规治疗的基础上,对照组接受利巴韦林喷雾剂治疗,研究组接受利巴韦林喷雾剂联合小儿豉翘清热颗粒治疗。观察两组疗效、临床症状、血清免疫球蛋白指标、外周血T淋巴细胞亚群指标和炎性因子的变化,比较两组不良反应发生率。结果：与对照组的临床总有效率相比,研究组的明显更高（P<0.05）。研究组的退热时间、皮疹消失时间、口腔溃疡消退时间均短于对照组（P<0.05）。治疗后,两组CD3⁺、CD4⁺、CD4⁺/CD8⁺升高,CD8⁺下降（P<0.05）。治疗后,研究组CD3⁺、CD4⁺、CD4⁺/CD8⁺高于对照组,CD8⁺低于对照组（P<0.05）。治疗后,两组血清免疫球蛋白（Ig）指标：IgA、IgM、IgG升高（P<0.05）。治疗后,研究组IgA、IgM、IgG高于对照组（P<0.05）。治疗后,两组白介素-6（IL-6）、肿瘤坏死因子-α（TNF-α）、白介素-1β（IL-1β）下降（P<0.05）。治疗后,研究组TNF-α、IL-6、IL-1β低于对照组（P<0.05）。两组不良反应发生率组间对比差异不显著（P>0.05）。结论：利巴韦林喷雾剂联合小儿豉翘清热颗粒治疗HFMD患儿,可有效调节炎性因子水平和免疫功能,促进临床症状改善。     

基质金属蛋白酶9对糖尿病足溃疡愈合影响的研究进展

在糖尿病足患者溃疡创面分泌物中,基质金属蛋白酶9 (matrix metalloproteinase-9,MMP-9)过高是预测糖尿病足的发生及足溃疡难愈的主要指标,其可能的机制包括:高水平MMP-9降低VEGF的表达、抑制成纤维细胞的生物学行为影响糖尿病足溃疡愈合;失衡的MMP-9/TIMP-1比值影响糖尿病足溃疡愈合。选择性MMP-9抑制剂(包括小分子抑制剂、高级伤口辅料抑制剂、基于干扰基因水平表达的RNA抑制剂)可以作为促进糖尿病足溃疡愈合的手段,但仍需大样本、多中心随机对照试验以及长期随访进一步验证其疗效及安全性。现查阅近年来涉及MMP-9和糖尿病足溃疡相关的文献,综述MMP-9对糖尿病足溃疡愈合的影响及其机制研究进展。