病毒性脑炎合并双侧急性视网膜坏死一例报道

病毒性脑炎是神经系统常见疾病,临床表现为意识障碍、癫痫发作、精神症状以及锥体外系症状。早期给予抗病毒及糖皮质激素治疗,大部分患者预后良好。急性视网膜坏死综合征(acute retinal necrosis syndrome,ARN)是最严重的眼内疾病之一,其突出临床表现是进行性视网膜坏死,     

视网膜中央动脉阻塞动物模型的研究进展

视网膜中央动脉阻塞是血管神经眼科急症,表现为急性无痛性单眼视力丧失,是中老年致盲的主要病因之一。目前关于视网膜中央动脉阻塞的具体发病机制和病理生理机制尚不明确,选择合适的动物模型进行视网膜中央动脉阻塞发病机制的研究和治疗药物的筛选尤为重要。本文对视网膜中央动脉阻塞动物模型的造模方法和研究进展加以综述,以期为视网膜中央动脉阻塞的精准诊疗提供依据。     

激素性股骨头缺血性坏死兔模型的构建☆

背景：成人股骨头缺血性坏死可导致股骨头塌陷和髋关节破坏,但其真正的病因和发病机制尚未完全明了。因此建立实验性动物模型是目前研究激素性股骨头缺血性坏死的重要手段之一。目的：建立兔激素性股骨头缺血性坏死模型,探讨其可能的发病机制。方法：将健康成年新西兰白兔以抽签法随机分成4组。对照组,注射生理盐水;激素组,注射甲基泼尼松龙3次;单次内毒素组,静脉注射大肠杆菌内毒素24 h后,立即注射甲基泼尼松龙3次;双次内毒素组,大肠杆菌内毒素注射24 h后重复给药1 次,随后注射甲基泼尼松龙3次。造模前及造模后行X射线片、MRI 检查及组织学检查、透射电镜观察,并计算空骨陷窝率。结果与结论：造模第8周时激素组、单次内毒素组、双次内毒素组空骨陷窝率较对照组明显增高(P < 0.01),并且双次内毒素组空骨陷窝率明显高于激素组和单次内毒素组(P < 0.01)。双次内毒素组较激素组及单次内毒素组股骨头出现坏死的时间更早、坏死的效果更显著,并且随着时间的推移股骨头坏死的效果越来越明显。说明在相同的实验条件下,实施双次内毒素与激素联合诱发股骨头坏死出现最早、坏死效果最明显,且骨陷窝空虚率随时间的延长而增加。关键词：股骨头缺血性坏死;甲基泼尼松龙;激素;内毒素;动物模型;骨陷窝     

改良激素性股骨头坏死动物模型的建立与评价

背景：在股骨头坏死发病机制的研究中,目前仍缺乏有效的动物模型,各种股骨头坏死治疗新方法的发展需要能够模拟人股骨头坏死自然病程动物模型的基础实验。 目的：通过联合应用马血清和低剂量甲基强的松龙建立激素性兔股骨头缺血性坏死动物模型。 方法：20只健康日本大耳白兔随机分成2组。实验组动物注入马血清,间隔2周后,再次注入马血清,第1次注射马血清后24 h肌肉注射甲基强的松龙,每隔1周注射1次,共8周。对照组动物单纯注射同等量的生理盐水。于第1次注射马血清前、注射甲基强的松龙后2,4,8周行血液学检查。并分别于注射甲基强的松龙后4,8周行MRI检查、苏木精-伊红染色和电镜观察股骨头缺血坏死情况。 结果与结论：与对照组比较,2,4,8周实验组三酰甘油、胆固醇均明显上升(P < 0.05);激活部分凝血活酶时间则明显下降(P < 0.05)。4周实验组MRI显示部分动物可见局部信号改变,8周时可见皮质下出血;对照组比较,4,8周实验组骨髓周围有坏死的骨髓细胞碎片存在,空骨陷窝率逐渐增加(P < 0.01);4周时实验组个别骨细胞结构模糊不清,或有大空泡;8周时部分骨细胞核破裂、核溶解,凋亡细胞大量出现,骨胶原结构排列紊乱。结果证实联合运用激素和马血清明显提高股骨头缺血性坏死的发生率,能够较好地建立激素性兔股骨头缺血性坏死动物模型。     

首发未治精神分裂症与单纯疱疹病毒感染的相关性研究

目的在首发未治的精神分裂症患者和健康对照组测定单纯疱疹病毒Ⅰ、Ⅱ型（HSV-Ⅰ、Ⅱ）抗体,探讨单纯疱疹病毒感染与精神分裂症发病之间的关系;单纯疱疹病毒感染与精神分裂症患病严重程度之间的关系。方法健康对照组共70例,均为北京安定医院的健康职工。患者组共67例,符合DSM-Ⅳ精神分裂症诊断标准。于抗精神病药物治疗前采血并评定PANSS及CGI量表,定性检测血清中HSV-Ⅰ、Ⅱ型的特异性IgG抗体。结果精神分裂症患者与健康对照组之间的HSV-Ⅰ、Ⅱ感染率的差异无统计学意义（P〉0．05）;HSV-Ⅰ、Ⅱ感染与患者发病时的疾病严重程度、HSV-Ⅰ、Ⅱ合并感染对其发病及疾病严重程度差异无统计学意义（P〉0．05）。结论在本研究样本量条件下,未发现精神分裂症患者的发病、疾病的严重程度与单纯疱疹病毒感染之间存在明确的相关性。     

构建酒精性股骨头坏死动物模型的理论依据及造模方法*

背景：酒精性股骨头坏死晚期股骨头易塌陷、致残率高,且目前缺乏有效的防治方法,故备受国内外学者的关注,因此,建立酒精性股骨头坏死动物模型,是进一步探讨其发病机制及临床防治的重要研究方向。 目的：总结国内外对酒精性股骨头坏死动物模型建立的研究进展。 方法：应用计算机分别在PubMed数据库和中国期刊全文数据库(CNKI)中检索1990-01/2010-01有关酒精性股骨头坏死的临床和基础实验研究的文章,检索词分别为“alcohol intoxication; avascular necrosis; animal model; research progress”和“酒精中毒;股骨头坏死;动物模型;研究进展”,纳入所述内容与酒精性股骨头坏死的动物模型相关的文献,排除发表时间较早或重复性研究。 结果与结论：收集到151篇相关文献,排除121篇不符合标准的文献,共纳入30篇符合标准的文献。经分析得出以下结论：通过对鼠、兔等动物过度饮酒或股骨头局部酒精介入,可导致股骨头髓内脂肪细胞增多、增大,小血管数量减少或阻塞,造成微循环障碍导致其缺血、缺氧而最终发生坏死,其发生机制接近于人类股骨头缺血性坏死的早期病理改变。结合国内外对酒精性股骨头坏死动物模型的研究现状,采用灌胃法,给予中国白兔烈性中国白酒(含体积分数55%乙醇)8 mL/(kg•d)4~8周处理,此种造模方法更适合目前实验研究。     

兔膝骨关节炎合并骨质疏松症动物模型的建立

背景：临床发现同时患有骨质疏松症和骨关节炎患者占相当大的比例,而且目前对骨质疏松与骨关节炎相互关系的认识不一致。目的：建立骨关节炎合并骨质疏松症的动物模型。方法：将14只新西兰大白兔随机等分为模型组和正常组。模型组新西兰大白兔行双侧卵巢切除,正常组新西兰大白兔不作任何处理。结果与结论：去除卵巢10周后,模型组大白兔关节软骨出现明显的退变,血清雌二醇、股骨骨密度水平较正常组显著下降(P < 0.01),而关节软骨Mankin评分比正常组显著增高(P < 0.01);且软骨Mankin评分与骨密度和血清雌二醇呈负相关,而骨密度与血清雌二醇水平呈正相关,表明实验成功建立了兔膝骨关节炎合并骨质疏松症动物模型。     

脊髓全横断大鼠模型的构建☆

背景：脊髓全横断模型在造模时常难以保证神经纤维的完全离断。 目的：构建大鼠脊髓全横断损伤模型。 方法：将大鼠随机分为模型组和假手术组。模型组构建脊髓T10节段全横断模型;假手术组动物仅打开椎管与硬脊膜而后缝合,但不损伤脊髓。建模后1,3,5,7 d分别进行BBB评分以评估后肢运动功能,检测其体感诱发电位和运动诱发电位来评估神经传导通路的完整性,并行形态学观察来评估脊髓肉眼观病理形态。 结果与结论：与假手术组相比,模型组大鼠在建模后1,3,5,7 d时,其BBB评分降低(P < 0.01),未检测出体感和运动诱发电位。形态学观察结果显示模型组大鼠脊髓完全横断,而假手术组脊髓形态完整。结果提示实验成功构建了大鼠脊髓全横断模型。     

兔腰椎间盘退行性病变模型的建立及影像学改变☆

背景：建立最佳的椎间盘退行性病变动物模型对了解椎间盘退行性病变的发生机制、预防与治疗均具有重要意义。 目的：以针刺损伤制备兔椎间盘退行性病变模型，通过X射线及MRI分析针刺损伤对椎间盘高度及退行性病变的影响。 设计：随机对照观察。 单位：解放军第二军医大学长海医院骨科。 材料：实验于2005-06/2006-04在解放军第二军医大学长海医院动物中心完成，选用6只健康新西兰大白兔，雌雄不拘，平均6月龄，体质量平均为2.5 kg，均来自解放军第二军医大学长海医院动物中心，许可证号码为SCXK (hu) 2002-0006。实验过程中对动物的处置符合动物伦理学标准。 方法：①采用腹膜后入路对实验兔腰椎进行手术，以L3~4椎间盘为正常对照, 不做处置；L4~5椎间盘作为假手术，只进行暴露；L5~6椎间盘暴露后用24 G针头从椎间盘的前外侧针刺3次。②分别于术前及术后4周采用Simens公司CR机拍摄腰椎正侧位X射线片，测量L3~4，L4~5及L5~6椎间隙高度，计算与术前椎间隙高度比值；采用Simens Avanto 1.5 T 医用超导型磁共振扫描仪检测各节段腰椎间盘T2加权信号，根据信号强度记分，4分为正常椎间盘，髓核内信号均匀、明亮；3分为轻微退行性病变椎间盘，T2加权信号部分降低；2分为中度椎间盘退行性病变，T2加权信号明显降低；1分为重度椎间盘退行性病变，其T2加权信号明显降低，而且伴有椎间隙狭窄。 主要观察指标：①腰椎X射线侧位片椎间盘高度变化。②椎间盘退行性病变程度。 结果：纳入实验兔6只，均进入结果分析，无脱落。①椎间盘高度变化：L3~4及L4~5术后与术前椎间盘高度比分别为0.982 5±0.017 08，0.972 5±0.017 08，均高于L5~6椎间盘高度比（0.550 0±0.025 82），差异有统计学意义（P < 0.01）。②腰椎MRI的T2加权像上观察椎间盘退行性病变程度：L3~4及L4~5椎间盘T2加权像信号得分分别为（4.00±0.0），（3.75±0.5）分，均高于L5~6椎间盘，差异有统计学意义（P < 0.01）。 结论：针刺损伤实验兔椎间盘4周后可造成椎间盘高度降低，并使椎间盘出现明显退行性病变。     

骨质疏松动物模型的研究现状☆

背景：骨质疏松的发病机制十分复杂,但又不能直接在人体上进行实验,需要复制类似人类骨质疏松的动物模型进行研究。 目的：全面分析各种骨质疏松动物模型的造模方法及优缺点,为今后研究骨质疏松症,在模型选择上提供参考。 方法：电子检索中国知识资源总库(CNKI)系列数据库和ESBCO Medline数据库1990-01/2010-07收录的骨质疏松模型的相关综述和论文报告。中文检索词为“骨质疏松,动物模型”;英文检索词为“osteoporosis,animal models”。共检索到469篇相关文献,对文章进行初审,纳入文献主题内容与此文联系紧密;原创、论点论据可靠的试验文章;观点明确,分析全面的文章。排除内容陈旧或重复文献及试验设计中不是采用随机对照试验的文章。 结果与结论：共纳入符合标准的38篇文献。目前用于骨质疏松症研究的动物模型主要有诱发性动物模型和转基因动物模型。各种骨质疏松动物模型可能只侧重于表现该疾病的某种病因、某一阶段、某些主要症状及某些病理生理变化,必须根据研究目的,选择合适的造模方法和实验动物。     

兔皮质引流静脉急性闭塞模型的建立

目的通过双极电凝闭塞皮质引流静脉,建立兔脑皮质引流静脉急性闭塞模型。方法青紫蓝兔35只,随机分为3组,其中A组15只,电凝顶叶皮质引流静脉1支;B组15只,电凝顶叶、枕叶皮质引流静脉各1支;C组(假手术组)5只,仅行开颅加切开硬脑膜处理,3组在造模后8h、24h、48h分别进行DSA检查,脑含水量、脑梗死率和静脉血栓形成率统计,大体标本、光镜对照研究。结果电凝法闭塞兔皮质引流静脉的成功率为100%,造模后经DSA证实所有电凝闭塞的皮质引流静脉已完全闭塞。A、B两组脑组织含水量与C组比较,均有升高(均P0.01),B组造模后8h、24h、48h较A组对应时段脑组织含水量均明显增高(均P0.01)。B组相邻2支皮质引流静脉电凝闭塞后的脑梗死率和静脉血栓形成率较A组均明显增加(均P0.05),假手术组均未见上述异常表现。结论电凝法制作的皮质引流静脉闭塞模型成功率高,稳定性和重复性好,是研究皮质静脉闭塞的理想模型。     

干细胞移植改善股骨头坏死缺血状态的实验及临床效应：20只模型兔及188例患者资料分析

BACKGROUND: Ischemic femoral head necrosis is caused by local vascular injury and blood-supply insufficiency. There exists no optimal treatment for the ischemic femoral head necrosis. Thus, the improvement of the blood supply to the femoral head seems to be a key point for the treatment. OBJECTIVE: To verify the curative effects of autologous bone marrow mesenchymal stem cell transplantation induced vascular regeneration on the improvement of ischemic femoral head necrosis via animal experiments and clinical observations. DESIGN: Contrast animal experiment and self-controlled clinical observation. SETTING: Cell Therapy Center, the 463 Hospital of Chinese PLA. MATERIALS AND PARTICIPANTS: ① Animals: Twenty Japanese white rabbits in either gender and weighing 3.0-4.0 kg were purchased from Animal Experimental Center, General Hospital of Shenyang Military Area Command of Chinese PLA. The animal experiments were coincident with the ethical standards. ② Participants: 188 patients with ischemic femoral head necrosis (335 hips) having whole following-up data were selected from Cell Therapy Center, the 463 Hospital of Chinese PLA from July 2004 to July 2007. There were 113 males and 75 females, and their ages ranged from 18 to 72 years. Diagnosis was done by using X-ray photographs, nuclide scanning, MRI and CT examinations. All patients provided the informed consent, and the study was approved by the local research ethics committee. METHODS: ① Animal experiments: The experiment was carried out at the Animal Experiment Center, General Hospital of Shenyang Military Area Command of Chinese PLA from January to June 2004. Ischemic femoral head necrosis models were established at both hindlimbs by using liquid-nitrogen refrigeration. The right side was regarded as transplantation group and the left one as control group. Mononuclear cells extracted from bone marrow were poured in the right femoral artery, while saline was poured in the left femoral artery. ②Clinical observations: Mononuclear cells were separated from autologous bone marrow of patients with ischemic femoral head necrosis after density gradient centrifugation. MAIN OUTCOME MEASURES: ①Four weeks later, angiogenesis at both femoral arteries was observed by arteriography by using digital subtraction anglography (DSA). Moreover, bilateral femoral head samples underwent pathological sections to observe bone regeneration and repair of femoral head 4 and 12 weeks later. ②Items including hip pain, walking distance and gait, abduction and internal rotation function changes of hip joint were observed in 3, 6, 12 and 24 months after stem cell transplantation in media femoral circum flex artery, lateral femoral circum flex artery and obturator artery. In 6 months after stem cell transplantation, angiogenesis and blood supply of femoral head were observed by using arteriography. In 6, 12 and 24 months after stem cell transplantation, morphological and ischemic changes of femoral head were observed by using CT, X-ray and MRI examinations. Harris scores were used to evaluate function of hip joint before and in 3, 6, 12 and 24 months after stem cell transplantation. RESULTS: Animal experiment: Twenty rabbits were involved in the final analysis. ① DSA-arteriography results: In 4 weeks after transplantation, blood-supply arteries in femoral head of right hindlimb in the transplantation group were more than those in the control group. ② Pathological results: In 12 weeks after transplantation, cartilage, lamellar bone and bone trabecula in the left femoral head were repaired remarkably, but left femoral head necrosis was not improved. Clinical observations: 188 patients were involved in the final analysis. ① Improvement of symptoms: Among 188 patients, 164 (87.3%) had remission of hip pain, 147 (78.4%) had function improvement, and 150 (80.0%) had elongation of walking distance. ② Imaging changes: At 6 months after transplantation, DSA-arteriography in 12 patients demonstrated that blood-supply arteries in femoral head were increased and thickened remarkably as compared with those before transplantation, and the blood flow was rapid. At 12-24 months after transplantation, lesion of bone matrix in 24 patients was improved under the X-ray, CT and MRI examinations. ③ Harris scores of hip joint: The scores at 6, 12 and 24 months after transplantation were significantly higher than those before transplantation (t= -3.423, -6.714, -9.039, P < 0.01). CONCLUSION: Autologous bone marrow mesenchymal stem cell transplantation can effectively improve and treat ischemic femoral head necrosis.     

Threshold suprachoroidal-transretinal stimulation current resulting in retinal damage in rabbits

The purpose of this study is to determine the threshold suprachoroidal-transretinal stimulation (STS) current that results in retinal damage in rabbits. Biphasic STS pulses (anodic first, frequency 20 Hz) were used to stimulate the retina of pigmented rabbits (n = 18) continuously for 1 h using a 100 microm diameter platinum wire electrode. The STS current that induced retinal damage after 1 h was determined by ophthalmoscopy or by fluorescein angiography (FA) independently. The effect of the pulse duration on the threshold current was investigated. Histological studies were performed after electrical stimulation experiments. The threshold for a safe current to the retina was 0.6 mA for a duration of 0.5 ms. The threshold for a safe charge increased approximately linearly with an increase of stimulus duration but the threshold for a safe current decreased logarithmically with an increase of duration. The threshold for a safe electrical energy remained almost constant for all durations. Histological examination showed severe retinal damage when the current exceeded the threshold, with more damage in the inner layers compared with the outer layers of the retina. The threshold for the safe current was higher than that reported for direct stimulation of neural tissues, suggesting that the STS method was safe and able to be used with a retinal prosthesis. Because the threshold for the safe charge was lower with shorter pulse durations, care should be taken using pulses of short durations.     

Alpha B-crystallin improved survival of retinal ganglion cells in a rat model of acute ocular hypertension

Increased endogenous αB-crystallin protein levels have been shown to reduce cell apoptosis,although the effects of exogenous αB-crystallin protein remain poorly understood.The present study established an acute ocular hypertension model in the right eye of Sprague-Dawley rats.Fluorogold retrograde tracing and immunofluorescence methods showed that the number of retinal ganglion cells decreased in the right eyes and caspase-3 expression increased following acute ocular hypertension.Intravitreal injection of αB-crystallin in the right eye increased the number of retinal ganglion cells and reduced caspase-3 expression.Results demonstrated that exogenous αB-crystallin protein inhibited caspase-3 expression and improved retinal ganglion cell survival following acute ocular hypertension.     

Presence of calpain-induced proteolysis in retinal degeneration and dysfunction in a rat model of acute ocular hypertension

The purpose of this study was to determine if calpain-induced proteolysis was associated with retinal degeneration or dysfunction in the rat acute ocular hypertensive model. Acute glaucoma was produced by elevation of IOP to 120 mm Hg for 1 hr. Retinal degeneration was evaluated by H&E staining and apoptosis was determined by TUNEL staining in histologic sections of retina. Electroretinogram (ERG) was carried out to evaluate changes in functionality. Activation of calpains was determined by casein zymography and immunoblotting. Total calcium in retina was measured by atomic absorption spectrophotometry. Proteolysis of alpha-spectrin, tau, cdk5, and p35 (a regulator of cdk5) were evaluated by immunoblotting. The thickness of inner plexiform layer (IPL) and inner nuclear layer (INL), and the number of cells in the ganglion cell layer (GCL) decreased after ocular hypertension. Numerous cells in the INL stained positive for TUNEL and some cells in the outer nuclear layer (ONL) showed TUNEL staining. The a-wave in ERG was temporarily decreased after ocular hypertension and then recovered to normal. In contrast, the b-wave was completely lost. Calpains were activated after ocular hypertension. Activation of calpains was associated with increased calcium in retina. Calpain-dependent proteolysis of alpha-spectrin, tau, and p35 were observed in retina after ocular hypertension. The results suggested that increased calcium and subsequent proteolysis by activated calpains was associated with the death of inner retinal cells due to acute ocular hypertension in the rat model. Calpain inhibitors may be candidate drugs for treatment of retinal degeneration and dysfunction resulting from glaucoma.     

Spreading of uncrossed retinal projection in superior colliculus of neonatally enucleated rabbits

Dutch-belted rabbits were enucleated shortly after birth and allowed to survive 14–26 weeks. In some animals, the second eye was then removed and the distribution of retinal axons studied. It was found that while there was no evidence of axonal sprouting in the lateral geniculate body, uncrossed retinofugal axons had spread throughout the lateral half of the superior colliculus, in areas normally innervated only by the contralateral eye. Other animals were prepared for electrophysiological recording, to see if neurons in the area of new axonal growth could be activated by light or electric shock to the optic nerve. Only four of 70 neurons tested could be driven by light, and only two of 26 tested could be driven by shock. All responsive neurons were judged to be located within the limits of the normal ipsilateral projection. It is concluded that while anatomical evidence of spreading of the uncrossed retinal input has been shown, the functional significance of this new growth is yet to be demonstrated.