显微手术治疗囊性听神经瘤的临床研究

目的:探讨显微外科开颅治疗囊性听神经鞘瘤的肿瘤全切情况及面、听神经的保留情况。方法:回顾性分析2006年8月至2013年9月我院收治的42例经枕下乙状窦后入路开颅囊性听神经鞘瘤手术患者的临床资料,同时对37例患者进行术后随访,并对结果进行统计学分析。结果:囊性听神经鞘瘤(42例)手术全切率simpson(Ⅰ-Ⅱ级)为64.28%(27例),次全切除率(simpsonⅢ级)为26.19%(11例),部分切除率为(simpsonⅣ级)为9.53%(4例),面神经解剖保留率为71.43%(30例),面神经功能保留率为14.29%(6例),听神经解剖保留率为7.1%,听神经功能保留3例,较实质性听神经瘤的手术效果差。结论:囊性听神经瘤的面、听神经解剖与功能保护尚有难度,需要进一步提高。     

Individual aortic baroreceptors are sensitive to different ranges of blood pressures

Many receptors,including thermal receptors and mechanical receptors,are only activated by stimuli within a clearly defined range of intensities.Differences in the receptive ranges enable individual receptors and their sensory centers to precisely detect the intensity of the stimulus and changes in intensity.Baroreceptors are the sensory terminals of the baroreflex.It is well understood that an increasing number of baroreceptors are recruited to produce afferent action potentials as the blood pressure increases,indicating that individual baroreceptors have different pressure thresholds.The present study revealed that individual baroreceptors could stop their afferent signals when the blood pressure exceeds a certain level,indicating that individual baroreceptors are sensitive to a specific range of blood pressure.The receptive ranges of individual baroreceptors differ in terms of the total range,the lower threshold,and the upper threshold.Of 85 baroreceptors examined in this study,the upper thresholds for about half were within the physiological blood pressure range.These results indicate that supraphysiological blood pressure is unlikely to be encoded by the recruitment of more baroreceptors.Instead,supraphysiological blood pressure levels might be signaled by an increase in the frequency of action potentials or by other mechanisms.In conclusion,our results indicate that rabbit baroreceptors are activated by blood pressure levels within specific receptive ranges.These findings should encourage further studies to examine the role of population coding of blood pressure by baroreceptors in the baroreflex.     

Building stable anisotropic tissues using cellular collagen gels

Combining cellular self-alignment within tethered collagen gels with stabilization through subsequent removal of interstitial fluid has yielded a new process for the fabrication of aligned cellular biomaterials. This commentary discusses the generation of engineered neural tissue for peripheral nerve repair using this combination of techniques, providing additional insight into the rationale underpinning the approach. By describing the potential benefits of using cell and matrix interactions to organize 3D hydrogels that can be stabilized to form tissue-like constructs, the article aims to highlight the potential for the approach to be used in the generation of a wider range of functional replacement tissues.     

Discovery and implications of transcellular mitophagy

The mitochondrial quality control system regulating mitochondria biogenesis, dynamics, and degradation has been extensively studied because of its roles in normal cell homeostasis and dysfunction due to aging or disease. Mitochondria degradation is generally thought to occur by autophagy and has therefore been viewed as a cell-autonomous process. In a recent study, we demonstrated that a large fraction of retinal ganglion cell mitochondria undergo lysosomal degradation within the astrocytes of the optic nerve head. It will be important to determine whether other neurons with long axons also use transcellular mitophagy, or transmitophagy, as a primary mitochondrial quality control mechanism either under normal physiological conditions or in disease. The elucidation of the underlying molecular mechanisms is necessary to determine whether defects in transmitophagy are involved in pathogenesis and whether it should become a therapeutic target.     

颈椎椎旁神经阻滞联合偏振光星状神经节照射治疗颈源性头痛的疗效观察

目的：观察颈椎椎旁神经阻滞联合直线偏振光红外线星状神经节照射治疗颈源性头痛的疗效。方法：120例颈源性头痛患者按照随机数字表法分为三组：颈椎椎旁神经阻滞联合偏振光星状神经节照射40例（A组）、颈椎椎旁神经阻滞40例（B组）、氨酚曲马多联合乙哌立松药物治疗组40例（C组）,三周为一疗程。治疗前后测定患者的疼痛视觉模拟评分（VAS）、颈椎活动度评分（ROM）、评定临床疗效。结果：三组治疗后疼痛视觉模拟评分（VAS）、颈椎活动度评分（ROM）均优于治疗前（P〈0．05）．A、B组治疗后VAS、ROM评分以及治愈率、有效率优于C组（P〈0．5）;A组VAS、ROM评分以及治愈率、有效率优于B组（P〈0．05）。结论：颈椎椎旁神经阻滞联合偏振光星状神经节照射和颈椎椎旁神经阻滞治疗治疗颈源性头痛疗效明显优于氨酚曲马多联合乙哌立松药物治疗组;颈椎椎旁神经阻滞联合偏振光星状神经节照射治疗颈源性头痛疗效优于颈椎椎旁神经阻滞。     

Neuroglobin involvement in visual pathways through the optic nerve

Neuroglobin is a member of the globin superfamily proposed to be only expressed in neurons and involved in neuronal protection from hypoxia or oxidative stress. A significant fraction of the protein localizes within the mitochondria and is directly associated with mitochondrial metabolism and integrity. The retina is the site of the highest concentration for neuroglobin and has been reported to be up to 100-fold higher than in the brain. Since neuroglobin was especially abundant in retinal ganglion cell layer, we investigated its abundance in optic nerves. Remarkably in optic nerves, neuroglobin is observed, as expected, in retinal ganglion cell axon profiles but also astrocyte processes, in physiological conditions, possess high levels of the protein. Neuroglobin mRNA and protein levels are ~ 10-fold higher in optic nerves than in retinas, indicating an important accumulation of neuroglobin in these support cells. Additionally, neuroglobin levels increase in Müller cells during reactive gliosis in response to eye injury. This suggests the pivotal role of neuroglobin in retinal glia involved in neuronal support and/or healing. This article is part of a Special Issue entitled: Oxygen Binding and Sensing Proteins.     

鱼类三叉神经运动核的形态学研究

目的:应用生物胞素法观察罗非鱼三叉神经运动核的形态及细胞分布特征.方法:本实验用罗非鱼,15只(性别不限),体长12～16 cm,动物浸入140 mg/L三卡因间氨苯酸乙脂甲磺酸盐{tricaine methanesulfonate (MS222)}溶液中麻醉,在手术显微镜下暴露神经,通过生物胞素(Biocytin)结晶追踪技术研究定位硬骨鱼类三叉神经运动核的形态及细胞分布.结果:①硬骨鱼类罗非鱼的三叉神经运动核分为腹侧和背侧两组细胞群.②三叉神经根注入列中两组细胞群都能观察到被标记的细胞.下颌神经注入列中被标记的细胞以背侧群为主.上颌神经及眼神经注入列中两群细胞都没有发现被标记细胞,但上颌神经组中能观察到神经终末及突触联系.结论:硬骨鱼类罗非鱼的三叉神经运动核分为两组细胞群.三叉神经运动核发出的纤维走行于下颌神经内.     

An optimisation-based model for full-body upright reaching movements

An optimal simulation 3D model for full-body upright reaching movements was developed using graphic-based modelling tools (SimMechanics) to generate an inverse dynamics model of the skeleton and using parameterisation methods for a sensory motor controller. The adaptive weight coefficient of the cost function based on the final motor task error (i.e. distance between end-effector and target at the end of movement) was used to correct motor task error and physiological measurements (e.g. joint power, centre of mass displacement, etc.). The output of the simulation models using various cost functions were compared to experimental data from 15 healthy participants performing full-body upright reaching movements. The proposed method can reasonably predict full-body voluntary movements in terms of final posture, joint power, and movement of the centre of mass (COM) using simple algebraic calculations of inverse dynamics and forward kinematics instead of the complicated integrals of the forward dynamics. We found that the combination of several control strategies, i.e. minimising end-effector error, total joint power and body COM produced the best fit of the full-body reaching task.