延髓后角脑啡肽超微结构定位和非突触部位释放——脑啡肽突触前抑制痛觉传递的形态学基础

阿片肽在后角镇痛的作用机理,被认为是通过突触前抑制一级传入纤维P物质释放的结果,然而始终未获得形态学的证实。鉴于一级传入纤维存在大量阿片受体的事实,曾提出阿片肽突触前抑制可能是通过非突触的轴-轴作用。为了验证这一设想,本文用免疫组化方法,详细观察了大鼠延髓后角浅层亮氨酸脑啡肽(L-ENK)轴突终末的突触结构和胞吐释放。电镜观察显示,延髓后角ENK终末可分为两类,第一类终末除了含圆形小清亮囊泡外,还有较多的大颗粒小泡(一般7个以上),主要分布于Ⅰ层,很少看到此类终末形成突触;第二类终末,一般含较多圆形清亮小泡和少量大颗粒小泡(一般不超过3个),它们分布于Ⅰ层和Ⅱ层,此类终末主要形成轴-树突触和少量的轴-体突触。只见到一例轴-轴突触,其突触后成分为未标记的R型终末,此外还见到ENK阳性树突成为中央终末的突触后成分。在去传入神经条件下,上述各类终末皆可见到ENK阳性大颗粒小泡的胞吐形成,它们皆位于非突触区,而在突触部位可见到清亮小泡胞吐像,上述结果提示后角ENK非突触部位释放可能是哭触后抑制一级传入纤维P物质释放的形态学基础。     

单侧前庭周围性眩晕的平稳跟踪实验结果分析

目的:对单侧前庭周围性眩晕的眼震图平稳跟踪实验(SPT)结果进行定性、定量分析并探讨其影响因素。方法:应用法国Synapsys视频眼震图仪对185例单侧前庭周围性眩晕患者(实验组)和51例正常人(对照组)行SPT和自发性眼震(SN)检测,以SPT水平眼跟踪波的增益值及SN为评定参数,对SPT眼动波形及增益进行定性、定量分析,并分析SPT眼动增益与SN强度之间的相关性。结果:实验组SPT呈现为Ⅰ、Ⅱ、Ⅲ型波,分别为105例(56.8%)、72例(38.9%)、8例(4.3%),存在SN者58例(31.4%),无Ⅳ型波。对照组仅呈现Ⅰ、Ⅱ型波,分别为38例(74.5%)、13例(25.5%),无Ⅲ、Ⅳ型波及SN。量化分析:对照组、实验组总体及定性划分后各型波的强、弱侧增益之间进行t检验,均差异有统计学意义(P<0.05);2组Ⅰ、Ⅱ型波的弱侧增益值之间均差异有统计学意义,强侧增益值之间均差异无统计学意义。对照组总体及定性划分后Ⅰ、Ⅱ波的左右侧增益值均差异无统计学意义(均P>0.05),强弱侧增益值比较均差异有统计学意义(均P<0.05)。实验组总体和定性划分后的Ⅰ、Ⅱ、Ⅲ型波的强、弱侧增益值比较,均差异有统计学意...     

白细胞介素-1β上调人鼻黏膜上皮细胞黏蛋白MUC2和MUC5B mRNA的表达

目的:探讨白细胞介素-1β(1L-1β)对鼻黏膜上皮细胞黏蛋白MUC2和MUC5B mRNA表达的影响.方法:在培养的第二代人鼻黏膜上皮细胞加入IL-1β(10μg/L)刺激24 h后,采用荧光定量RT-PCR检测人鼻黏膜上皮细胞中MUC2和MUC5B mRNA的定量表达.结果:在培养的鼻黏膜上皮细胞上均检测到MUC2和MUC5B mRNA的表达,IL-1β刺激组MUC2 mRNA定量表达[(39.26±6.10)×104拷贝/μg]高于对照组[(5.70±4.16)×104拷贝/μg],差异有统计学意义(P<0.01);IL-1β刺激组MUC5BmRNA定量表达[(5.72±2.06)×105拷贝/μg]高于对照组[(1.11±0.72)×10.拷贝/μg],差异有统计学意义(P<0.05).结论:在培养的鼻黏膜上皮细胞中IL-1β组的MUC2和MUCSB mRNA表达均高于对照组,提示IL-1β可能具有上调鼻黏膜上皮细胞黏蛋白mRNA的表达作用.     

内耳拟老化大鼠模型对噪声损伤易感性研究

目的:应用本研究小组建立的内耳拟老化模型,研究其对噪声损伤的敏感性,并探讨线粒体DNA缺失(mtDNA)在大鼠对噪声损伤易感的可能作用.方法:2月龄Wistar大鼠32只随机分为4组,A组每日皮下注射D-半乳糖150 mg/kg体重,持续8周;继而暴露于声强为110 dB SPL的噪声环境中,每日连续刺激4 h,持续2 d.B组每日皮下注射0.9%生理盐水150 mg/kg体重,持续8周,然后给予噪声暴露,噪声条件同A组.C组用药方法同A组,D组用药方法同B组,C组和D组均不予噪声暴露.造模后2周测试ABR反应阈改变,并测试各组大鼠膜迷路总超氧化物歧化酶活力(T-SOD)、丙二醛(MDA)水平,同时应用巢式PCR(nest PCR)方法检测大鼠膜迷路mtDNA 4834缺失突变,并对PCR 产物进行测序.结果:A组大鼠ABR反应阈改变[(66.250±6.409)dB SPL]较B组[(35.625±4.955)dB SPL]明显提高,差异有统计学意义(P<0.01).A组T-SOD显著下降,MDA水平明显提高,与B组差异有统计学意义(P<0.01).大鼠内耳组织mtDNA4834缺失突变率分别为:A组87.5%(7/8),B组12.5%(1/8),C组75.0%(6/8),D组0(0/8).结论:内耳拟老化模型大鼠对噪声性聋易感,大鼠内耳组织mtDNA缺失突变可增加模型大鼠对噪声性听力损伤的易感性.     

鼻咽通气管单夜治疗阻塞性睡眠呼吸暂停低通气综合征初步观察

目的 探讨用鼻咽通气管实验治疗阻塞性睡眠呼吸暂停低通气综合征(OSAHS)的疗效及可行性.方法 符合OSAHS诊断标准的32例患者,采用Somte多道睡眠仪行第一夜即治疗前多道睡眠图(PSG)检查,第二夜整夜佩戴硅胶的鼻咽通气管实验治疗,同时行PSG监测.比较两夜的PSG监测指标,数据符合正态分布以x-±s表示,差异比较采用配对t检验.结果 佩戴鼻咽通气管单夜的耐受率为90.6%(29/32).29例采用鼻咽通气管实验治疗时的呼吸暂停低通气指数(AHI)由(44.7±16.0)次/h降至(14.6 4±10.0)次/h;最长呼吸暂停时间由(44.3 4±11.5)s降至(30.1±13.2)s;最低动脉血氧饱和度由(0.722±0.080)提高到(0.861±0.070);动脉血氧饱和度低于0.90时间在睡眠总时间中的构成比由(19.2±18.O)%降至(1.5±4.0)%,7项指标均较治疗前有明显改善(配对t检验,P值均<0.001).29例治疗当夜和次日,OSAHS主观症状明显改善,以AHI<20次/h且降低幅度≥50%作为成功的标准,鼻咽通气管单夜治疗成功率为65.5%(19/29).6例无效的患者,可能与舌后区阻塞所占比例较大有关.结论 单夜初步实验显示,鼻咽通气管对改善OSAHS腭后区阻塞有较好效果,为探索OSAHS新治疗技术提供参考.此外,鼻咽通气管实验治疗效果在判断阻塞平面方面也可能有应用前景,有待深入研究.     

Assessment of T Cell Activation in a Mouse Model of Traumatic Facial Nerve Injury

Objective To investigate T cell activation following facial nerve axotomization and latent neuroimmunologic mechanisms in traumatic facial paralysis. Methods A murine model of facial nerve transaction was used. Lymphocytes from cervical and mesenteric lymph nodes in BABL/c mice at specific times were collected and expression rates of CD69 on T cells were assessed by flow cytometry. Results Infiltrating T cells were detected around the facial neurons in the facial nerve nucleus in mice whose facial nerve was transected. Immunofluorescent staining showed recruitment of activated T cells. Three days post-facial nerve transection, the expression rate of CD69 on T cells from cervical draining lymphoid nodes (CDLNs) was significantly different from that on T cells from mesenteric lymph nodes (MLNs)(P=0.0457), whereas the latter was similar to that in animals undergoing sham surgeries and that in blank control animals (p=0.2817 and 0.2724, respectively). Two weeks post-nerve transection, the T cell CD69 expression rate from CDLNs remained at a higher level and than that in the sham-operation animals (p=0.0007). At two weeks, CD69 expression rate on T cells from MLNs was also up-regulated and different compared with the sham-operation animals and with itself at three days post-operation (p=0.0082 and 0.0133, respectively). Conclusion T cells appear to be activated and up-regulated in CDLNs following facial nerve transection. There is even evidence of T cell activation in MLNs at 2 weeks post-nerve transection. This suggestes an alteration of immune response from local to general immunity in the acute stage of facial nerve trauma, which may help coordinating and controlling the scales and orientation of the neuroimmune response during the pathogenesis and progression of facial nerve trauma.     

Otosclerosis: Incidence of positive findings on temporal bone computed tomography (TBCT) and audiometric correlation in Korean patients

Objective

To assess the incidence of otosclerotic foci identified by temporal bone computed tomography (TBCT) in Korean and to determine the correlation between the extent of otosclerotic foci and audiometric findings.

Methods

Thirty-one patients (37 ears) who were surgically confirmed otosclerosis and underwent preoperative TBCT scan were included. Patients underwent pre- and postoperative audiometric evaluation and TBCT. The mean air conduction (AC) thresholds and bone conduction (BC) thresholds, air–bone gap (ABG), and the difference between pre- and postoperative ABGs were determined. Otosclerotic foci were identified by the presence of hypodense lesions near the fissula ante fenestram and the otic capsule in the TBCT. The areas with hypodense lesions and the density ratio of the otosclerotic foci were compared by pre- and postoperative audiometric parameters.

Results

Hypodense lesions were identified by the TBCT in 27 out of 37 cases (73%). Fenestral types were found in 23 cases and combined fenestral and cochlear types in 4 cases. There was a significant correlation between the density ratio of the otospongiotic foci and the postoperative mean ABG (P = 0.03). However, there was no correlation between the size of the hypodense area and any of the audiometric parameters tested (P > 0.05).

Conclusion

The rate of positive TBCT findings for otosclerosis in our series was 73%. The extent of the hypodense lesion did not correlate with the preoperative hearing levels. However, the density ratio of the hypodense lesion influenced the surgical outcomes.     

经舌骨入路口咽前壁癌的综合治疗

目的 探讨对口咽前壁癌患者施行以经舌骨入路切除为主的综合治疗效果.方法 回顾性分析2005年5月至2010年10月24例口咽前壁即舌根会厌区癌患者的临床资料.24例患者中T27例,T3 2例,T4 15例;N0 7例,N1 4例,N2 12例,N3 1例.均经舌骨入路,行全舌根和(或)半舌切除+喉部分切除9例,舌部分切除+喉全切除7例,舌全切除+喉部分切除7例,舌部分切除(全舌根+半舌)1例.胸大肌岛状肌皮瓣修复全舌(7例)或部分舌(9例)及咽侧壁缺损(16例),修复颈部皮肤缺损1例;游离前臂皮瓣+胸骨舌骨肌瓣修复半舌、咽侧及部分咽后缺损1例;胸骨舌骨肌瓣修复舌根2例;直接拉拢缝合4例.20例行双侧颈清扫术,4例行单侧颈清扫术.术前放疗5例,术后放疗16例.结果 24例患者原发灶切缘均阴性,17例(70.8％)患者淋巴转移阳性.术后咽瘘3例,其中2例舌部分切除+喉全切除胸大肌皮瓣一期修复术后4d出现咽瘘者,经清创换药后拉拢缝合;1例舌根全切除+喉部分切除术后放疗后咽瘘者以胸大肌皮瓣修复.17例保留喉功能患者中16例于术后1～6个月内拔管,恢复正常饮食,构音尚可,另1例发音、吞咽尚好,但堵管后通气不足,未能拔管.随访3年以上21例,Kaplan-Meier法计算3年总生存率72.6％.结论 经舌骨入路口咽前壁癌切除是较为理想的术式之一,手术缺损较大,多需一期修复,综合治疗尚能取得较满意结果.     

听觉剥夺后大鼠听皮层神经元的形态学变化和SHP-2基因的表达

目的研究双侧耳蜗毁损后大鼠听皮层神经元细胞的形态学变化和蛋白酪氨酸磷酸酶2型（src-homology domain containing protein tygosine phosphatase type 2,SHP -2）基因的表达。方法选取SD大鼠48只,随机分为4个实验组（2周组、4周组、6周组、8周组）和4个相应的对照组,每组6只。实验组动物行双侧耳蜗损毁术,通过HE染色和Nissl染色观察听皮层神经元细胞的形态学变化,用RT -PCR技术检测各组听皮层神经元细胞的SHP-2基因的表达,行相对定量分析。结果 HE染色和Nissl染色可见各实验组大鼠听皮层神经元细胞的凋亡形态随时间延长而加重,呈多样化表现;各对照组大鼠听皮层细胞形态正常。实验2、4、6、8周组SHP-2基因的RT -PCR相对表达量分别为1．1±0．28、1．5±0．04、2．5±0．08、11．0±0．06,随时间延长呈上升趋势,各实验组之间差异均有统计学意义（P＜0．05）。结论听觉剥夺可导致听皮层神经元细胞凋亡,凋亡的程度随时间延长逐渐加重;SHP-2基因可促进听皮层神经元细胞的增生,增生的程度也随时间延长而加重;在这两个相互拮抗的因素中,凋亡是最终的结果。