神经源性声带运动障碍与喉神经电生理

声带运动障碍的病因和临床表现复杂多变，涉及多学科，从病因上分为神经源性和非神经源性。对于神经源性声带运动障碍的诊治，首先通过喉镜等检查明确有无声带运动障碍及严重程度，值得注意的是声带纵向张力变化障碍也属于运动障碍的范畴；然后采用喉肌电图（LEMG）检查进行定性分析，在确诊神经源性损伤后，进一步对神经损伤部位进行定位诊断并查找导致神经损伤的病因；同时根据喉部神经电生理评估结果，判断预后。最后综合上述的评估结果制定相应的治疗策略。     

Nerve ultrasound reference data in children from two to seven years

ObjectiveWe examined selected peripheral and spinal nerves of children aged between two and seven years.MethodHigh resolution ultrasound was performed in 116 children (2–7 years of age) at 19 predefined landmarks of median, ulnar, tibial, fibular, sural and radial nerves, the vagus as well as cervical spinal nerve 5 and 6. Further, side-to-side measuring and grey-scale analysis was done at selected nerve sites.ResultsNerves of children were on average smaller than those of adults. Nerve growth correlates significantly with age in all nerves, the mean values were similar in the age of two to four years and five to seven years. Body mass index (BMI) and gender showed moderate effect at some nerve sites, however not uniformly in all. A side-to-side difference of up to 30% in median, and up to 20% in tibial nerve can occur in healthy individuals. Grey-scale analysis for echointensity has been performed in median, ulnar and tibial nerves.ConclusionNerve size increases with age, BMI and gender have moderate effect. A side-to-side-difference of up to 30% can exist.SignificanceReference values of nerve cross-sectional area, side-to-side-difference and echo intensity are necessary to detect nerve pathology in children as well as in adults.     

Non-viral transfer of BDNF and uPA stimulates peripheral nerve regeneration

Peripheral nerves connect brain and spinal cord with the extremities and inner organs, and nerves injury can lead the disability and social exclusion. Growth factors and other natural stimulators of regeneration processes look very promising as future medicines. In our study, we tested the influence of genetic constructions that contain genes of brain-derived neurotrophic factor and urokinase plasminogen activator on nerve's structure and function after traumatic and ischemic injuries. Injection of pVax1-hBDNF and pVax1-muPA after traumatic injury led to better restoration of nerve's structure and function compared to similar parameters of control group mice. In ischemic injury model pVax1-hBDNF and pVax1-muPA slowed and reduced the damage progression and stimulated nerve regeneration as well. However, the treatment with pVax1-muPA was less effective after the traumatic injury. As we chose a non-viral method of gene delivery during our study the optimal conditions of plasmid intramuscular delivery were also determined.     

Ex Vivo Radiation Leads to Opposing Neurite Growth in Whole Ganglia vs Dissociated Cultured Pelvic Neurons

BackgroundProstatic radiation therapy (RT) often causes erectile dysfunction (ED) and the mechanisms governing RT-induced ED are unclear with a lack of therapeutic strategies.AimTo determine the effects of ex vivo RT on major pelvic ganglion (MPG) neuron survival, and neurite growth in whole vs dissociated culture.MethodsMPGs were removed and irradiated (0 or 8 Gy) from male Sprague Dawley rats. For dissociated culture, MPG neurons were digested in collagenase/dispase and cultured on coverslips. Immunofluorescent staining for beta-tubulin III (TUBB3; neuron marker), neuronal nitric oxide synthase (nNOS; nitrergic marker), tyrosine hydroxylase (TH; sympathetic marker), and terminal deoxynucleotidyl transferase dUTP nick end labeling assessed neurite length, branching, autonomic neuron density, and apoptosis. For whole organ culture, MPGs were grown in Matrigel. Gene expression of apoptotic markers (caspase 1, 3), TUBB3, nNOS, TH, and Schwann cells (Sox10, Krox20, glial fibrillary acid protein) was measured in whole organ cultured MPGs by quantitative polymerase chain reaction.OutcomesAfter 72 hours, neurite length, branching, autonomic neuron density, and apoptosis were assessed, and gene expression was measured.ResultsRT increased apoptosis in dissociated neurons measured by terminal deoxynucleotidyl transferase dUTP nick end labeling (P < .001) and whole MPG culture via upregulation of caspase 3 gene expression (P < .05). Nitrergic neurons were markedly decreased in irradiated dissociated culture (P < .05), while nNOS gene expression was upregulated in irradiated whole organ culture (P < .05). The proportion of dissociated sympathetic neurons and whole organ TH gene expression remained unchanged after RT. Interestingly, RT dissociated neurites were 22% shorter than controls, while RT whole organ neurites were 15% longer than controls (P < .01). MPG Schwann cells markers (Sox10, Krox20) were elevated after RT in whole organ culture.Clinical TranslationProstatic RT leads to increased neuronal cell death and less erectogenic nitrergic neurons contributing to ED.Strengths & LimitationsThe advantages of dissociated neuron culture include distinct neurites which are easily measured for apoptosis, length/branching, and specific neuron types. In contrast, whole MPG culture is advantageous as it contains all the supporting cells present in vivo.ConclusionThe 2 different culture methods demonstrated opposing neurite growth after RT indicating the importance of supporting cell network to promote pelvic neuron neuritogenesis and survival following RT.Randolph JT, Pak ES, Koontz BF, et al. Ex Vivo Radiation Leads to Opposing Neurite Growth in Whole Ganglia vs Dissociated Cultured Pelvic Neurons. J Sex Med 2020;17:1423–1433.     

皮肤瘙痒神经传导介质的研究进展

瘙痒是皮肤科的一种常见症状,是多因素相互作用的结果,其发生受到中枢和外周机制的双重调控,但具体发生机制尚不十分清楚。近年来随着研究的不断深入,多种物质如组胺、乙酰胆碱、5-羟色胺、蛋白酶和蛋白酶相关受体、细胞因子、阿片样肽等介质在瘙痒产生过程中起重要作用,这些介质通过刺激C类神经纤维或直接与皮肤感觉神经纤维受体相结合来介导瘙痒。本文就将皮肤瘙痒的神经传导及传导介质作一综述。     

环化酶激活剂对大鼠感觉神经元保护作用的实验研究

目的探讨环化酶激活剂（前列腺素E1、腺苷及Zn^2＋离子）对周围神经损伤后感觉神经元的保护作用.方法在大鼠坐骨神经夹毁模型术后21 d,取背根节用图像分析法观测前列腺素E1（PGE1）、腺苷（Ade）和高Zn^2＋饲料（Zn^2＋）对背根节细胞数、核偏心率及核等圆径的影响,并与人胎盘神经生长因子（hNGF）的作用相比较.结果NGF及环化酶激活剂组与夹毁对照组相比都能增进背根节细胞的存活和减轻核偏移（P＜0.05）;NGF组和高Zn^2＋饲料组在背根节细胞存活数、核偏心率及核等圆径方面与假手术组无差别（P＞0.05）.结论PEG1、Ade及Zn^2＋离子等环化酶激活剂对DRG神经元均有保护作用,其中Zn^2＋离子的保护效应与NGF无差别.     

Distribution patterns of transforaminal injections in the cervical spine evaluated by multi-slice computed tomography

Transforaminal injections are sometimes used for the diagnosis and treatment of painful conditions in the lumbar and to a lesser degree in the cervical spine. The technique is most often used when investigating/treating radiculopathy caused by degenerative disease. But how selective are the nerve root blocks? What possible structures other than the intended nerve root are affected from such injections? This study was undertaken in order to try to answer these questions, as no study focusing on the possible spread from the transforaminal selective nerve root blocks in the cervical spine has been performed earlier. In three groups of patients, each group including three patients, we injected three different volumes (0.6, 1.1 and 1.7 ml) with a transforaminal technique in the cervical spine. In all the injections, a small amount of contrast media was added. The spread of the injections were then investigated using multi-slice computed tomography with reconstructions. The imaging revealed a possible effect on other nerve roots than the intended ones when a larger volume was used for the root blocks. The spread was related to the injected volume as well as to local anatomy (size of foraminal area). In this study, only 0.6-ml injections could be accepted for being selective enough for diagnostic investigations.     

Sciatic Neuropathy: Case Report and Discussion of the Literature on Postoperative Sciatic Neuropathy and Sciatic Nerve Tumors

Sciatic nerve injury and dysfunction is not an uncommon cause of lower extremity symptoms in a musculoskeletal practice. We present the case of a man who presented with lower extremity weakness, pain, and cramps, and was initially diagnosed at an outside institution with bilateral S1 radiculopathies and recommended for spine surgery. He came to us for a second opinion. Electrodiagnostic testing revealed an isolated sciatic neuropathy and the patient was referred for imaging, which showed a sciatic nerve sheath tumor. Review of the literature on sciatic neuropathies shows that there can be many possible etiologies of sciatic nerve dysfunction, but that hip arthroplasty continues to be the leading risk factor. Sciatic nerve tumors are not commonly described in the literature and their definitive management remains unclear.     

The effect of MS-818, a pyrimidine compound,on the regeneration of peripheral nerve fibers of mice after a crush injury

One of the pyrimidine compounds, 2-piperadino-6-methyl-5-oxo-5,6-dihydro(7H)pyrrolo[3,4-d]pyrimidine (MS-818), has neurotropic effects in vitro. Therefore, we studied the effect of MS-818 on the regeneration of the peroneal nerve in C57BL/6J mice after a crush injury. Two test groups, which received a daily intraperitoneal injection of 5 mg/kg or 10 mg/kg MS-818, respectively, were compared with controls, which received daily intraperitoneal injections of physiological saline, over a 14-day period. The maximum foot-width ratio (crushed side/uncrushed side) was obtained on days 1, 8 and 14 after the crush injury, and the various morphometric parameters were evaluated at both 5 and 10 mm distal to the proximal portion of the crush site. The significant effects of MS-818 included a larger maximum foot width (P<0.04) and a greater number of unmyelinated axons per nerve at both levels (P<0.003) in both test groups than in controls. MS-818 had no significant effects on body weight, the increase of total transverse fascicular area after the crush injury, the total number of myelinated fibers with their size distributions, or the number of nuclei of Schwann cells and macrophages. Therefore, we conclude that MS-818 promotes axonal sprouting and elongation after a crush injury in mice.