Inhibition of experimental autoimmune encephalomyelitis in Lewis rats by nasal administration of encephalitogenic MBP peptides: synergistic effects of MBP 68-86 and 87-99

Induction of mucosal tolerance by inhalation of soluble peptides with defined T cell epitopes is receiving much attention as a means of specifically down-regulating pathogenic T cell reactivities in autoimmune and allergic disorders. Experimental autoimmune encephalomyelitis (EAE) induced in the Lewis rat by immunization with myelin basic protein (MBP) and Freund's adjuvant (CFA) is mediated by CD4+ T cells specific for the MBP amino acid sequences 68-86 and 87-99. To further define the principles of nasal tolerance induction, we generated three different MBP peptides (MBP 68-86, 87-99 and the non- encephalitogenic peptide 110-128), and evaluated whether their nasal administration on day -11, -10, -9, -8 and -7 prior to immunization with guinea pig MBP (gp-MBP) + CFA confers protection to Lewis rat EAE. Protection was achieved with the encephalitogenic peptides MBP 68-86 and 87-99, MBP 68-86 being more potent, but not with MBP 110-128. Neither MBP 68-86 nor 87-99 at doses used conferred complete protection to gp-MBP-induced EAE. In contrast, nasal administration of a mixture of MBP 68-86 and 87-99 completely blocked gp-MBP-induced EAE even at lower dosage compared to that being used for individual peptides. Rats tolerized with MBP 68-86 + 87-99 nasally showed decreased T cell responses to MBP reflected by lymphocyte proliferation and IFN-gamma ELISPOT assays. Rats tolerized with MBP 68-86 + 87-99 also had abrogated MBP-reactive IFN-gamma and tumor necrosis factor-alpha mRNA expression in lymph node cells compared to rats receiving MBP 110-128 nasally, while similar low levels of MBP-reactive transforming growth factor-beta and IL-4 mRNA expressing cells were observed in the two groups. Nasal administration of MBP 68-86 + 87-99 only slightly inhibited guinea pig spinal cord homogenate-induced EAE, and passive transfer of spleen mononuclear cells from MBP 68-86 + 87-99-tolerized rats did not protect naive rats from EAE. Finally, we show that nasal administration of MBP 68-86 + 87-99 can reverse ongoing EAE induced with gp-MBP, although higher doses are required compared to the dosage needed for prevention. In conclusion, nasal administration of encephalitogenic MBP peptides can induce antigen-specific T cell tolerance and confer incomplete protection to gp-MBP-induced EAE, and MBP 68-86 and 87-99 have synergistic effects. Non-regulatory mechanisms are proposed to be responsible for tolerance development after nasal peptide administration.      

Apoptotic cell death in mouse models of GM2 gangliosidosis and observations on human Tay-Sachs and Sandhoff diseases

Tay-Sachs and Sandhoff diseases are autosomal recessive neurodegenerative diseases resulting from the inability to catabolize GM2 ganglioside by beta-hexosaminidase A (Hex A) due to mutations of the alpha subunit (Tay-Sachs disease) or beta subunit (Sandhoff disease) of Hex A. Hex B (beta beta homodimer) is also defective in Sandhoff disease. We previously developed mouse models of both diseases and showed that Hexa-/- (Tay-Sachs) mice remain asymptomatic to at least 1 year of age while Hexb-/- (Sandhoff) mice succumb to a profound neurodegenerative disease by 4-6 months of age. Here we find that neuron death in Hexb-/- mice is associated with apoptosis occurring throughout the CNS, while Hexa-/- mice were minimally involved at the same age. Studies of autopsy samples of brain and spinal cord from human Tay-Sachs and Sandhoff diseases revealed apoptosis in both instances, in keeping with the severe expression of both diseases. We suggest that neuron death is caused by unscheduled apoptosis, implicating accumulated GM2 ganglioside or a derivative in triggering of the apoptotic cascade.      

奥曲肽治疗肝硬变食管静脉曲张破裂出血

0　引言　我院 1996 - 0 6 / 1998- 0 7用奥曲肽治疗肝硬变食管静脉曲张破裂出血 19例 ,并与垂体后叶素作了对照 .1　对象和方法1.1　对象　经内镜证实食管静脉曲张破裂出血 37例 ;男 32例 ,女 5例 ;年龄 42～ 6 9岁 .肝炎后肝硬变 32例 ,乙醇性肝硬变 3例 ,血吸虫性肝硬变 2例 .按就诊顺序随机分为治疗组19例 ,对照 18例 .估计出血量 :治疗组 (146 3.6± 375 .8) m L;对照组 (144 9.5± 36 8.4) m L .出血至治疗间隔时间 :治疗组(11.6± 3.5 ) h;对照组 (11.2± 3.6 ) h.两组的年龄、性别、肝功 Child分级、食管静脉曲张程度、出血量、出…     

五灵胶囊治疗慢性肝炎的临床随访观察

0　引言　五灵丸治疗慢性病毒性肝炎取得了较好的疗效 [1 ] ,但五灵丸为大蜜丸 ,不易被患者所接受 ,且其消化道副作用较明显 .为此 ,我们改进剂型 ,研制成五灵胶囊 ,为明确其能否保持远期疗效 ,我们对用该药治疗的患者进行随访观察 ,同时与五灵丸的疗效进行比较 .1　对象和方法1.1　病例选择　按慢性肝炎的诊断标准选择住院患者 10 0例 ,随机分为两组 .治疗组为五灵胶囊组 ,对照组为五灵丸组 .每组各 5 0例 .治疗组轻度 19例 ,中度 2 0例 ,重度 11例 .对照组轻度 2 0例 ,中度 18例 ,重度 12例 .两组均选择 18～5 8岁 ,病程 1～ 2 0 a.平均 4…     

激光生物效应及医学应用研究

激光作用于生物体会产生物理、化学或生物学的效应,激光正是通过这些效应达到医学基础研究、诊断和治疗疾病的目的.本文简介了激光与生物组织相互作用所产生的生物效应,概述了激光生物效应在生物学和医学研究中的应用.     

N-(6,6-二甲基-2-庚烯-4-炔基)-N-甲基-α-取代-1-(4-取代)萘甲胺类的合成及抗真菌活性

根据氮唑类和烯丙胺类抗真菌化合物的构效关系、作用机理。设计合成了30个N-(6,6-二甲基-2-庚烯-4-炔基)-N-甲基-α-取代-1-(4-取代)萘甲胺类化合物。初步体外抑菌试验结果表明,大多数目标化合物对八种试验菌株都有不同程度的抗真菌活性。化合物Ⅰ_1a的真菌活性大致与克霉唑相当,对白念珠菌的活性明显高于naftifine和terbinafine,但对其它七种菌株的活性均不及naftifine和terbinafine;化合物Ⅲ_1a对八种试验菌株的活性均与terbinafine相当。     

4-{[2-(1H-咪唑基)-1-(4-取代苯基)乙氧基]甲基}苯甲酸类化合物的合成及其抑制血小板聚集的作用

根据咪唑类和吡啶类TXA₂合成酶抑制剂的构效关系和作用机制,设计合成了20个4-{[2-(1H-咪唑基)-1-(4-取代苯基)乙氧基]甲基}苯甲酸类化合物。初步体外药理试验结果表明,所有化合物都有不同程度的抑制TXA₂合成酶能力,从而抑制花生四烯酸(AA)诱导的血小板聚集。化合物15的抑酶活性最强,以IC₅₀值相比,其活性为Dazoxiben的55.6%。并初步探讨了这类化合物的构效关系。     

血管加压素对哮喘大鼠下丘脑-腺垂体-肾上腺皮质功能的影响

目的:观察在哮喘急性发作过程中,大鼠血浆中血管加压素、促肾上腺皮质激素和皮质醇以及下丘脑中血管加压素、促肾上腺皮质激素释放因子水平的变化,进而探讨急性哮喘发作对机体应激水平的影响以及血管加压素在此过程中的作用。方法:实验于2005-12/2006-07在南京医科大学生理学系实验室进行。①实验一:取32只大鼠单纯随机分为对照组、哮喘激发组、假激发组和生理盐水吸入组4组,每组8只。对照组腹腔注射生理盐水,其余大鼠腹腔注射卵蛋白致敏;实验开始第15天,对照组和哮喘激发组大鼠超声雾化吸入10g/L卵蛋白溶液20min,1次/d,连续3d,生理盐水吸入组雾化吸入10g/L生理盐水,假激发组不吸入任何蒸汽。②实验二:40只大鼠单纯随机分成对照组、假手术组、生理盐水组、侧脑室给药组和静脉给药组5组,每组8只;对照组腹腔注射生理盐水,其余大鼠腹腔注射卵蛋白致敏后第15天给药。侧脑室给药组侧脑室注射血管加压素受体阻断剂d(CH2)5Tyr(Me)AVP0.3μg;生理盐水组侧脑室注射1μL生理盐水;假手术组进行侧脑室操作,但不注射;静脉给药组按1mg/kg剂量静脉给与d(CH2)5Tyr(Me)AVP。给药1h后,雾化吸入10g/L卵蛋白溶液20min。如是处理,连续3d后。③实验完成后处死动物,放射免疫法分别测定下丘脑中促肾上腺皮质激素释放因子和血管加压素水平,以及血浆中血管加压素、促肾上腺皮质激素和皮质醇质量的浓度。结果:72只大鼠进入结果分析。①实验一结果:哮喘激发组血浆中血管加压素、促肾上腺皮质激素和皮质醇水平高于对照组[(7.92±0.97),(4.32±0.93)ng/L;(805.8±162.1),(279.7±88.5)ng/L;(12.02±1.25),(5.24±1.12)ng/L,P<0.05],生理盐水吸入组和假激发组高于对照组,但低于哮喘激发组(P<0.05)。哮喘激发组下丘脑中血管加压素和促肾上腺皮质激素释放因子水平高于生理盐水吸入组和假激发组[(17±1),(10±1),(11±2)pg;(7937±198),(6210±198),(6165±203)pg;P<0.05],以上3组均高于对照组(P<0.05)。②实验二结果:侧脑室给药组血浆中促肾上腺皮质激素和皮质醇水平为(480.4±101.7),(9.75±1.97)ng/L,低于假手术组、生理盐水组和静脉给药组,后3组间差异不显著。结论:①致敏过程使机体应激水平升高,同时下丘脑-腺垂体-肾上腺皮质轴的功能增强,可能是哮喘急性发作的重要原因之一。②降低下丘脑血管加压素的释放可以改善哮喘激发时的下丘脑-腺垂体-肾上腺皮质轴的功能亢进。     

Amplatzer封堵器的生物学性能及经导管介入治疗房间隔缺损

目的:评价经导管置入Amplatzer封堵器治疗继发孔房间隔缺损的治疗效果。方法:①选择2002-08/2006-04在兰州市第一人民医院心外科住院的继发孔型房间隔缺损65例,男26例,女39例;平均年龄(18±8)岁;平均房间隔缺损直径(19.3±7.2)mm。纳入患者对手术方案知情同意。②手术所用封堵器为美国公司的Amplatzer房间隔缺损封堵器,是一种新型的适于关闭二孔型房间隔缺损的装置,它由具有自膨胀性的双盘及连接双盘的腰部三部分组成。双盘状结构恢复记忆形状后可以稳定封堵房间隔缺损的边缘部分,降低残余分流的发生率。③根据选择封堵器大小的方式(即球囊测量或经胸超声心动图直接观察)将患者分为球囊测量组38例和经胸超声心动图测量组27例。均在透视及经胸超声心动图监视下经导管置入Amplatzer封堵器封堵房间隔缺损。同时测量患者缺损扩张直径、封堵器大小,记录X射线透视时间和手术时间。④术后即刻、24h、3个月及1年分别行经胸超声心动图、心电图及X射线检查评价治疗效果。⑤超声心动图显示完全无分流为无分流;残余分流血流宽度≤1mm为微量分流;血流宽度1.0～2.0mm为少量残余分流;血流宽度2～4mm为中量残余分流;血流宽度>4mm为大量残余分流。⑥组间计量资料差异比较采用两个独立样本t检验,组间手术效果比较采用两个独立样本的等级资料秩和检验。结果:①技术成功率:65例房间隔缺损患者,64例封堵器置入成功,技术成功率为98%。②选择封堵器直径:球囊测量组缺损扩张直径为(20.4±6.1)mm,选择的封堵器直径为(21.6±5.7)mm,与经胸超声心动图测量组相近[(22.5±4.3),(25.1±4.9)mm,P>0.05]。③术后残余分流情况:术后即刻经胸超声心动图显示,球囊测量组35例完全无分流,经胸超声心动图组有23例,差异不明显(P>0.05);术后24h,球囊测量组36例完全无分流,经胸超声心动图组有24例,差异不明显(P>0.05);术后3个月,球囊测量组37例完全无分流,经胸超声心动图组有25例,差异不明显(P>0.05);术后1年完成随访的52例患者均未见封堵器移位及房间隔缺损再通。④X射线平片检查:全部显示肺血减少,右心房、室缩小。结论:封堵器直径比球囊测量的房间隔缺损扩张直径大1.0～2.0mm,比超声心动图测量的大2～6mm封堵效果好,成功率高。