Role of disturbance of ependymal ciliary movement in development of hydrocephalus in rats

We have developed a new in vitro method of quantitatively analyzing ciliary movement in the ependymal wall of the aqueduct in rats. An axial slice of the midbrain containing ependymal wall was placed in a culture dish filled with a culture medium containing latex beads 1 m in diameter at a concentration of 10⁷ beads/ml. The movement of the beads caused by flow of culture medium generated by the to-and-fro ciliary movement was recorded by a high speed video system attached to an inverted phase-contrast microscope. Ciliary movement was expressed by the speed of the latex beads (m/s). Aqueductal ciliary movement in congenitally hydrocephalic HTX rats, congenitally hydrocephalic WIC-Hyd rats, and other normal rats was evaluated. The results suggest that in congenitally hydrocephalic WIC-Hyd rats the degree of hydrocephalus related strongly to the degree of ciliary dyskinesia, but in congenitally hydrocephalic HTX rats it did not. Considering this discrepancy, we attempted to see whether or not hydrocephalus was caused by artificial disturbance of ependymal ciliary movement in vivo. We found that continuous infusion of metavana date, an inhibitor of ciliary movement, into the III ventricle of normal Sprague-Dawley rats for 7 days induced dilatation of the ventricular system. Although the question whether or not disturbance of aqueductal ependymal ciliary movement is related to the development of human congenital hydrocephalus is debatable, the results of the present in vitro and in vivo experimental investigations appear to suggest that the disturbance of ciliary movement in the aqueduct could at least be one of the factors contributing to the inducement of hydrocephalus in experimental conditions.     

Use of a Calibration Balloon Tube to Size the Pouch and Channel in Gastroplasty Procedures

Gastroplasty is currently one of the most common surgical procedures performed on the morbidly obese for weight loss. An adequate result can be assured only if the pouch that is created is less than 30 ml and the channel that connects that pouch to the distal stomach is approximately 1 cm in diameter. The current method to size the pouch is to occlude the esophagus and the outlet of the pouch and to measure with a manometer through a naso-gastric tube. We contend this method is both time consuming and adds to the potential of complications. Through the use of a calibration balloon tube the size of the pouch can be quickly and safely estimated. It can also be used to size the channel between the pouch and the distal stomach and check for leaks. The technique of how this tube has been used over the past 6 years is described. By the use of a calibration balloon tube, three problem areas in gastric stapling surgery for morbid obesity are avoided, namely: inappropriate pouch size, inappropriate channel size and postoperative leaks.     

变温实验中冷和热刺激反应强度的差异

目的　了解变温实验检查中冷和热刺激对患者反应强度变化有无影响。方法　应用眼震电图仪和冷热刺激仪对 12 0例有眩晕症状的患者进行冷热实验检查 ,观察他们在不同温度刺激下眼震的最大慢相角速度。结果　单热刺激以及先冷后热刺激中的热刺激引起的患者眼震的最大慢相角速度较冷刺激组明显大 (P <0 .0 1)。结论　变温实验中患者对热刺激的反应强度要较冷刺激强     

The relationship between transverse plane leg rotation and transverse plane motion at the knee and hip during normal walking

The purpose of this study was to test the clinical hypothesis that the magnitude and temporal characteristics of rearfoot complex motion are closely correlated with those of the transverse plane motion at the knee and hip. Twenty subjects underwent kinematic assessment during walking at 108 steps/minute. The transverse plane rotation of the leg relative to the foot was used to indicate rearfoot complex pronation and supination. Taking into account errors inherent in kinematic assessment involving skin mounted markers, it is unlikely that a correlation exists between the range of internal leg rotation during the contact phase and the total range of transverse plane leg rotation during gait and the corresponding values for the transverse plane motion at the knee and hip. Correlation tests were performed to assess the temporal characteristics of the motions at the joints that showed that there was no correlation between the transverse plane motion in the rearfoot complex, knee and hip. Thus the hypothesis that the magnitude and temporal characteristics of rearfoot complex motion are closely correlated with the transverse plane motion at the knee and hip was rejected.     

神经妥乐平治疗周围神经病变的疗效观察

目的：观察神经妥乐平治疗周围神经病变的临床效果。方法：静脉滴注神经妥乐平，比较用药前后患者神经系统症状及神经传导速度的变化。结果：治疗后患者视觉模拟评分下降，患侧肢体神经传导速度改善。治疗前后比较，有显著性差异。结论：对多种疾病导致的周围神经病患者，使用神经妥乐平治疗可获得较好疗效。     

Spatial encoding properties of subnucleus reticularis dorsalis neurons in the rat medulla

Denervation of the synergists of the medial gastrocnemius (MG) muscle in the cat hind leg results in a progressive increase in the magnitude of burst activity in the MG muscle during walking. The increase in burst magnitude is associated with an increase in the slope of the relationship between the magnitude of individual MG bursts and the amplitude of ankle flexion during stance. This finding is consistent with the hypothesis that the increase in MG burst magnitude is due to an increase in gain of reflex pathways reinforcing the activation of MG. The increase in slope is use-dependent since it was not observed when the leg was released from a cast that immobilized the leg for 6 days.     

Measurements of preferred walking speed in subjects with central and peripheral vision loss

BACKGROUND: Previous mobility studies have used Preferred Walking Speed (PWS) in order to determine the walking efficiency in terms of the Percent Preferred Walking Speed (PPWS) of visually impaired adults. PWS has been measured in previous studies using the sighted guide (SG) and non-sighted guide (NSG) techniques. This study compared the NSG, SG and string (ST) (subjects walked by holding on lightly to a cardboard tube attached to a piece of string) techniques of measuring PWS in visually impaired subjects. METHODS: Forty visually impaired subjects with central and peripheral vision loss were recruited. PWS was measured using the NSG, SG and ST techniques. For each technique, PWS was determined by recording the time taken for a subject to walk an unobstructed, straight 20-m corridor. RESULTS: There were no significant differences in PWS using the SG, NSG and ST techniques. CONCLUSION: For assessing walking efficiency, either the SG, NSG or ST technique could be employed when measuring PWS in visually impaired subjects.     

用市电干扰校准心电图机走纸速度

校准心电图走纸速度的方法,在实际操作中,钟表检查法不宜掌握、浪费记录纸、误差较大;正弦波检查法因条件所限,无正弦波发生器或频率不准,不易实现。经过多年实践,总结出用市电50Hz交流干扰法校准心电图走纸速度,其方法简单实用、容易掌握、不用任何设备、准确度高、适用于维修人员和临床医务人员,减少误诊,提高临床诊断率。     

Exoskeleton plantarflexion assistance for elderly

Elderly are confronted with reduced physical capabilities and increased metabolic energy cost of walking. Exoskeletons that assist walking have the potential to restore walking capacity by reducing the metabolic cost of walking. However, it is unclear if current exoskeletons can reduce energy cost in elderly. Our goal was to study the effect of an exoskeleton that assists plantarflexion during push-off on the metabolic energy cost of walking in physically active and healthy elderly. Seven elderly (age 69.3 ± 3.5 y) walked on treadmill (1.11 m s²) with normal shoes and with the exoskeleton both powered (with assistance) and powered-off (without assistance). After 20 min of habituation on a prior day and 5 min on the test day, subjects were able to walk with the exoskeleton and assistance of the exoskeleton resulted in a reduction in metabolic cost of 12% versus walking with the exoskeleton powered-off. Walking with the exoskeleton was perceived less fatiguing for the muscles compared to normal walking. Assistance resulted in a statistically nonsignificant reduction in metabolic cost of 4% versus walking with normal shoes, likely due to the penalty of wearing the exoskeleton powered-off. Also, exoskeleton mechanical power was relatively low compared to previously identified optimal assistance magnitude in young adults. Future exoskeleton research should focus on further optimizing exoskeleton assistance for specific populations and on considerate integration of exoskeletons in rehabilitation or in daily life. As such, exoskeletons should allow people to walk longer or faster than without assistance and could result in an increase in physical activity and resulting health benefits.     

Analysis and Comparison of Friction Stir Welding and Laser Assisted Friction Stir Welding of Aluminum Alloy

Friction Stir Welding (FSW) is a solid-state joining process; i.e., no melting occurs. The welding process is promoted by the rotation and translation of an axis-symmetric non-consumable tool along the weld centerline. Thus, the FSW process is performed at much lower temperatures than conventional fusion welding, nevertheless it has some disadvantages. Laser Assisted Friction Stir Welding (LAFSW) is a combination in which the FSW is the dominant welding process and the laser pre-heats the weld. In this work FSW and LAFSW tests were conducted on 6 mm thick 5754H111 aluminum alloy plates in butt joint configuration. LAFSW is studied firstly to demonstrate the weldability of aluminum alloy using that technique. Secondly, process parameters, such as laser power and temperature gradient are investigated in order to evaluate changes in microstructure, micro-hardness, residual stress, and tensile properties. Once the possibility to achieve sound weld using LAFSW is demonstrated, it will be possible to explore the benefits for tool wear, higher welding speeds, and lower clamping force.