Epitopes of human brain acetylcholinesterase

The main purpose of the present work was to identify B-cell epitopes on human brain acetylcholinesterase (AChE) by the synthetic peptide approach. Five hundred and seventy-four decapeptides comprising amino acids No. n to n+9 (where n denotes the residue number of the 583 amino acids in the primary structure of human brain AChE and is an integer in the range 1-574) were synthesized, using the multipin combinatorial chemical synthesis technique, and biotinylated. Epitopes of human brain AChE were detected by enzyme-linked immunosorbent assay (ELISA) and compared with the predicted epitopes of human AChE by 'Goldkey' software. Among 574 synthetic decapeptides, 47 decapeptides at 11 antigenic regions showed immunoreactivity with mouse anti-human brain AChE polyclonal antibodies. The minimum sequence of epitope was defined at every antigenic region explored. The locations and sequences of the former ten continuous epitopes at the 11 antigenic regions of the human brain AChE had been identified as follows: TPVLVWIY (112-119), RTVLVSMNY (143-151), LLDQRLALQW (173-182), RRATQLAH (246-253), VFRFSFVPV (294 approximately 302), KDEGSYFLVY (332-341), RVYA (424-427), LMRY (476-479), KAPQWPPY (496-503), GLRAQACAFW (523-532). The rate of hits of the predicted epitopes from the software came out at 33%. In our work, the epitopes of human AChE have been mapped by purified polyclonal antibody at eleven distinct sites in the primary structure.     

CoQ10 fails to protect brain against focal and global ischemia in rats

OBJECTIVE: Release of oxygen free radicals occurs following cerebral ischemia. Studies show that oxygen free radicals mediate ischemic brain injury. CoQ10 is a potent free radical scavenger and may offset brain injury associated with reperfusion. We tested exogeneous CoQ10 as a neuroprotectant in rats following both global and focal ischemic insults. METHODS: Rats were subjected to either 4-vessel occlusion ischemia (4-VO, 10 min occlusion, 7-day survival) or middle cerebral artery occlusion (MCAO, 120 min-occlusion, 22.5 h survival). Regional cerebral blood flows (rCBF) and physiological variables such as blood pressure, pO2, pCO2, plasma glucose and hematocrit were monitored and measured in focal ischemia. The animals were randomized to receive treatments of either phosphate buffered saline (PBS) vehicle or CoQ10 following global or focal ischemia. Injection times were at the end of ischemia and 3 h later for both models of ischemia. Histological outcomes are expressed as a percentage of hippocampal CA(1) cell injury in global ischemia or percentage of cortical infarct over that of non-ischemic hemisphere in focal ischemia. RESULTS: In global ischemia, animals treated with PBS vehicle and CoQ10 had 86+/-5% (n=8) and 83+/-10% (n=8), respectively, of hippocampal CA(1) cell injury (P>0.05). The percentage of infarct volumes in animals following focal ischemia were 23+/-9% (control, n=10) and 25+/-9% (CoQ10, n=10). There were no temperature or physiological differences between the two treatment groups. CONCLUSION: Acute treatment with CoQ10 via intraperitoneal injection does not prevent neuronal injuries following global and focal ischemia.     

The influence of human intervertebral disc tissue on the metabolism of osteoblast-like cells

Extensive studies have been performed to evaluate different factors that may affect on spinal interbody fusion, but the role of intervertebral disc tissue in the fusion process remains unclear. To study the influence of intervertebral disc tissue on osteoblast metabolism, we harvested disc tissue from patients who had undergone spinal surgery. The nucleus pulposus and annulus fibrosus were separately co-cultured with osteoblast-like cells SaOS-2 by means of culture inserts or organ culture. We assayed alkaline phosphoatase activity, 3H-thymidine incorporation into the DNA, and production of collagen type I, IL-1beta, IL-6, IL-10, and TNF-alpha. Exposure of the nucleus pulposus (NP) to osteoblast-like cells revealed stimulation of alkaline phosphatase production, 3H-thymidine incorporation and collagen type I production. Exposure of the annulus fibrosus (AF) stimulated 3H-thymidine incorporation and collagen type I production, but did not affect ALP activity. IL-6 was detected after application of NP and AF. Interleukin IL-10, IL-1beta and TNF-alpha were all below detection levels after application of disc tissue. Our findings show that frozen disc tissue stimulates the metabolism of osteoblast-like cells in vitro.     

共轭亚油酸对肥胖大鼠PPARγ基因表达及血清瘦素水平的影响

目的　研究不同剂量共轭亚油酸 (CLA)对饮食诱导肥胖大鼠PPARγ基因、瘦素、血糖、血脂的影响。方法　选用雄性Wistar大鼠 ,随机分为对照组、高脂组、高脂 +CLA组 (每 10 0g饲料含CLA分别为 0 75g、1 5 0g、3 0 0g) ,于第 12周末处死动物 ,计算脂 体比 ,测定大鼠血糖、血脂及瘦素水平 ,并应用RT PCR的方法检测大鼠白色脂肪组织过氧化物酶体增殖物激活受体γ(PPARγ)的表达水平。结果　CLA可降低肥胖大鼠血糖、甘油三酯 (TG)、总胆固醇 (TC)及瘦素水平 ,增加脂肪组织PPARγmRNA的表达水平。结论　CLA可降低肥胖大鼠血糖、血脂 ,并可通过激活PPARγ下调瘦素水平 ,有改善肥胖大鼠的瘦素抵抗作用。     

应用飞行时间质谱仪快速鉴定细菌的初步研究

目的　研究基质辅助激光解析电离飞行时间质谱对细菌快速鉴定的影响因素。方法　应用 8种细菌 ,比较了不同培养基 (哥伦比亚血琼脂、伊红美兰琼脂、普通营养琼脂 )及培养时间对细菌质谱图的影响。结果　不同的培养基及培养时间会对细菌质谱图产生影响。结论　选择合适的培养基及培养时间可以提高细菌检测的准确率     

所有权与经营权分离是城市公立医院改革和发展的途径

传统卫生管理体制承袭了计划经济的所有特征,价格扭曲的宏观政策环境、资源的集中计划配置体制与公立医院在微观上的缺乏经营自主权三者并存.这种制度安排越来越不适应市场经济条件下卫生改革和发展的需要,而卫生经济体制改革始自微观经营机制,核心是两权分离和放权让利,这是自然的,同时也是正确的改革方向.     

稳态强噪声暴露后听神经动作电位及神经丝蛋白表达的观察

目的 观察豚鼠暴露于稳态强噪声后听神经复合动作电位(CAP)及神经丝蛋白(NFP)的变化。方法 选用20只(40耳)Preyer反射正常的健康豚鼠，分为4组，噪声暴露后存活7天组(N-7d)、14天组(N-14d)和2个月组(N-2m)各5只，空白对照组(C)5只。噪声强度130dB(A)SPL，连续暴露5小时，于暴露前、暴露后3、7、14天、暴露后2个月分别测试CAP—N1波反应阈。免疫组化反应分别检测对照组、暴露后7、14天组、暴露后2个月组动物耳蜗内NFP的表达。结果稳态强噪声暴露后CAP—N1波反应阈明显增高，于暴露后7天基本稳定。暴露后7、14天NFP表达无明显变化，暴露后2月NFP表达显著减弱。结论 130dB(A)SPL稳态强噪声暴露5小时可以导致豚鼠CAP中重度永久性阈移，噪声损伤的早期NFP改变不明显，耳蜗NFP染色反应随着存活时间延长逐渐减弱，反映了损伤后神经纤维中骨架蛋白存在变性过程。     

α-受体阻滞剂对老化大鼠耳石保护作用的扫描电镜观察

目的　应用扫描电镜观察老化大鼠及α 受体阻滞剂 (络斯宝 )处理后耳石的变化。方法　Wistar雄性大鼠 15只分为正常对照组 (n =5 )、老化组 (n =5 )、老化 +洛斯宝组 (n =5 )。老化造模完成后 ,分别进行扫描电镜观察。结果　正常大鼠的耳石形态正常 ;老化大鼠耳内可见线团样耳石融合、变平 ,有巨大耳石出现 ,可见球形和异形耳石 ,在移行细胞区 ,可见较多的耳石吞噬现象 ,球囊斑见小片状纤毛缺失 ;洛斯宝处理组可见球形耳石 ,有粘结现象 ,但一般均为光滑形态或绒线团外观 ,未见巨型耳石 ,移行区耳石数量较老化组少。结论　老化大鼠耳石出现明显异常 ,α 受体阻滞剂 (洛斯宝 )对耳石器有一定的保护作用     

慢性鼻-鼻窦炎鼻息肉内镜鼻窦术后上颌窦口黏膜恢复过程观察

目的 试图通过对内镜鼻窦手术(endoscopic sinus surgery，ESS)后患者鼻腔鼻窦黏膜的内镜、光镜、透射电镜和扫描电镜下连续动态观察，揭示病变黏膜转归的过程。方法 选取2001年1～12月行ESS的慢性鼻一鼻窦炎伴鼻息肉患者31例(53侧)作为研究对象，其中Ⅱ型2期11例(20侧)、3期12例(20侧)，Ⅲ型8例(13侧)。分别于ESS术前、术后2～3周、8～11周、13～16周钳取上颌窦口后囟相同部位的黏膜组织进行观察。结果 术前均可见上皮剥蚀、鳞状上皮化生、腺体及纤维组织增生(53侧)；微管结构异常、线粒体减少(53侧)。术后2～3周，形态学观察与术前比较没有明显的改变。术后8～11周，纤毛柱状细胞增多，并可见许多带有微绒毛的柱状细胞和大量短纤毛，所有病例均可见病理性腺体及纤维组织增生。术后13～16周，Ⅱ型2、3期和Ⅲ型患者术腔光滑干净，上皮化较好(50侧)，窦口通畅(53侧)。纤毛覆盖面积增加，方向一致(50侧)。微管结构清晰，线粒体狭长致密(49侧)。3侧无纤毛柱状细胞排列整齐，形成病理性修复。结论 ESS术后，黏膜形态的基本恢复一般需要3个月左右；有些病理改变是不可逆的；病变程度与黏膜修复情况有关；术中尽可能多地保留黏膜组织、术后局部及时清理换药，有利于黏膜纤毛的形态和功能的恢复。     

Expression and significance of nuclear factor kappaB in laryngeal carcinoma]

OBJECTIVE: To explore the expression and significance of NF-kappaB in laryngeal carcinoma. METHOD: The protein expression of NF-kappaB p65 in laryngeal carcinoma tissue and normal laryngeal tissue was examined by Western blot; NF-kappaB DNA binding activity was examined by electrophoretic motility shift assay (EMSA) in 20 laryngeal carcinoma tissue and 12 normal laryngeal tissue. RESULT: The levels of NF-kappaB p65 protein and NF-kappaB DNA binding activity in the laryngeal carcinoma tissue were higher than those in normal laryngeal tissue. CONCLUSION: NF-kappaB may be an important oncoprotein and involves in the occurrence and development of laryngeal carcinoma.