Bubble-Induced Color Doppler Feedback Correlates with Histotripsy-Induced Destruction of Structural Components in Liver Tissue

Bubble-induced color Doppler (BCD) is a histotripsy-therapy monitoring technique that uses Doppler ultrasound to track the motion of residual cavitation nuclei that persist after the collapse of the histotripsy bubble cloud. In this study, BCD is used to monitor tissue fractionation during histotripsy tissue therapy, and the BCD signal is correlated with the destruction of structural and non-structural components identified histologically to further understand how BCD monitors the extent of treatment. A 500-kHz, 112-element phased histotripsy array is used to generate approximately 6-?×?6-?×?7-mm lesions within ex vivo bovine liver tissue by scanning more than 219 locations with 30–1000 pulses per location. A 128-element L7-4 imaging probe is used to acquire BCD signals during all treatments. The BCD signal is then quantitatively analyzed using the time-to-peak rebound velocity (t_prv) metric. Using the Pearson correlation coefficient, the t_prv is compared with histologic analytics of lesions generated by various numbers of pulses using a significance level of 0.001. Histologic analytics in this study include viable cell count, reticulin-stained type III collagen area and trichrome-stained type I collagen area. It is found that the t_prv metric has a statistically significant correlation with the change in reticulin-stained type III collagen area with a Pearson correlation coefficient of ?0.94 (p?<0.001), indicating that changes in BCD are more likely because of destruction of the structural components of tissue.     

引导性反馈在内科模拟教学中的应用分析

目的探讨引导性反馈在内科模拟教学中的应用价值。方法此次研究所纳入的内科实习生均自2017年1月—2019年1月份进入本院,抽选量为80例。以随机数字表法完成分组,将应用常规内科模拟教学的40例内科实习生设立为参照组,将联合引导性反馈的40例患者设立为观察组。两组均由同组教师进行授课教学,教学后进行考核。经考核成绩分析和发放教学满意度问卷,比对两组实习生的教学情况。结果观察组的操作技巧、人文关怀、应急能力、理论知识分值更高,与参照组差异有统计学意义(P<0.05)。观察组的教学满意度更高,与参照组差异有统计学意义(P<0.05)。结论在内科模拟教学中开展引导性反馈,可强化学生对学习的反思,使学生教学积极性得到提高,有效提高学生教学成绩,改善教学质量。     

Postural instability in Parkinson’s disease: Review and bottom-up rehabilitative approaches

The aims of this narrative review are to provide scientific support to characterize the postural instability commonly observed in Parkinson’s disease (PD), and to emphasize how bottom-up rehabilitation programs stimulating the sole of the foot can improve postural stability in PD. Postural instability is a typical characteristic of individuals with PD, which increases the frequency of falls and may worsen their consequences. It thus seems relevant to diagnose these alterations as early as possible, in order to develop specific rehabilitative treatment. The association between sensitivity of the sole of the foot and postural instability in individuals with PD is linked to the key role of peripheral alterations of the sensorimotor system in balance and motor symptoms. By enhancing sensory feedback coming from the feet, bottom-up stimulation allows patients to improve their sensorimotor control. In clinical practice, health practitioners can use sensory stimulation to improve postural control. By improving postural stability, a decrease in fall risk can be achieved and the secondary impairments associated with falls prevented.     

内镜柔性器械腱鞘传动模型及实验研究

目的 建立内镜柔性器械腱鞘系统的推力传动模型，研究影响传动效率的关键因素。方法 建立腱鞘系统在器械推送作用下力和位移的传动模型并进行仿真计算；搭建腱鞘系统传动测试的实验平台以验证模型的准确性，研究传动速度、腱鞘直径比、弯曲半径等对传动效率的影响。结果 腱鞘传动过程中存在显著的非线性传递现象，传动模型仿真与实验结果基本符合；传动速度、腱鞘直径比、弯曲半径均对内镜柔性器械的推力传动有较大影响，对位移传动的影响相对小一些。结论 该模型可用于内镜柔性器械中腱鞘系统推力传动的计算，提供给医生器械工作末端的力反馈，以保证器械的安全操作和提高手术效果；在内镜柔性器械的精准控制中需要综合考虑传动速度、腱鞘传动比、弯曲半径等对运动传递的影响。     

Influence of intra‐oral sensory impairment by anaesthesia on food comminution and mixing in dentate subjects

Sensory input from sensory receptors regarding food morsels can affect jaw motor behaviours during mastication. The aim was to clarify the effects of intra‐oral sensory input on the food‐comminuting and food‐mixing capacities of dentate subjects. Eleven dentate subjects without sensory dysfunction in their oro‐facial region participated in this study. Local anaesthesia was achieved on the periodontal structures and on the oral mucosa of the subjects' preferred chewing side by injecting a lidocaine solution with adrenalin. At baseline (control) and after anaesthesia, data on the subjects' food‐comminuting and food‐mixing capacities were gathered. The food‐comminuting capacity was quantified by measuring the degree of pulverisation of peanuts (objective hardness; 45·3 [Newton, N]) after a prescribed 20 chewing strokes. The food‐mixing capacity was measured as the degree of immixture of a two‐coloured paraffin wax cube after 10 chewing strokes. Wax cubes of three different hardness levels were used (soft, medium and hard: 20·3, 32·6 and 75·5 [N], respectively) and were chewed in random order. After anaesthesia, the subjects' food‐comminuting capacity significantly decreased (P < 0·001), as did the food‐mixing capacity for each hardness level of the wax cubes (P < 0·01). A significant correlation was observed between the objective hardness values and the anaesthesia effects for the food‐mixing capacity (P < 0·05), indicating that after anaesthesia, deterioration of the mixing capacity increased as the hardness increased. In conclusion, intra‐oral sensory input can affect both food‐comminuting and food‐mixing capacities.