Acute and long-term humoral immunity following active immunization of rabbits with inacctivated spores of various Encephalitozoon species

Microsporidia of the genus Encephalitozoon are increasingly being reported as a cause of severe, often disseminated infections, mainly in patients with acquired immunodeficiency syndrome (AIDS). Immunological identification of each of the three recognized species (E. cuniculi, E. hellem, and E. intestinalis) requires the availability of specific immune sera. All sera available thus far have been generated by direct inoculation of rabbits with virulent microsporidian spores. This study demonstrates for the first time that subcutaneous immunization with inactivated spores of E. cuniculi, E. hellem, or E. intestinalis is capable of generating highly active rabbit hyperimmune sera to the homologous antigens, with maximal titers being 1:5,120, 1:1,280, and 1:2,560, respectively, as determined by the indirect immunofluorescence technique (IIF). Broad cross-reactivity of the rabbit antisera with all heterologous Encephalitozoon antigens was determined by IIF and immunogold electron microscopy; however, only the E. hellem immune serum strongly cross-reacted with spores of Enterocytozoon bieneusi. During the 35-month follow-up period the antibody titers to the homologous antigens declined to 1:640, 1:160, and 1:320, respectively. The observed decay curves for antibody titers against E. cuniculi, E. hellem, and E. intestinalis were fitted using mathematical modeling, resulting in a predicted duration for specific immune responses of about 7 years on average. Knowledge of the magnitude and duration of specific immune responses is a prerequisite for further evaluation of the concept of using inactivated microsporidian spores in the quest for vaccines against microsporidian infections. Received: 10 April 2000 / Accepted: 18 July 2000     

CD3+木瓜提取物对ApoE基因缺陷小鼠血脂及炎性相关因素的影响

目的观察木瓜提取物对ApoE基因缺陷小鼠血脂水平、主动脉窦斑块中巨噬细胞活化及肿瘤坏死因子(TNF-α)水平的影响。方法30只雄性ApoE基因缺陷小鼠随机分为3组:对照组、低剂量组和高剂量组,低剂量组和高剂量组分别在基础饲料上添加5%和10%的木瓜提取物喷雾干燥颗粒,饲养16周后经小鼠眼眶静脉取血后处死动物,酶法测定血脂水平、采用免疫组化分析主动脉窦斑块中TNF-α的表达水平和采用免疫荧光反映斑块CD68阳性表达水平与巨噬细胞阳性表达率。结果低剂量组和高剂量组的血清TC和LDL-C显著低于对照组(P<0.05),木瓜提取物能显著下调斑块中TNF-α的表达水平以及减少巨噬细胞的阳性率。结论木瓜提取物降低了血清脂蛋白胆固醇水平(TC和LDL-C),减少了炎性因子TNF-α表达以及减弱巨噬细胞参与程度,预示其可能具有减缓动脉斑块发生发展的抗动脉粥样硬化作用。     

含氮二膦酸盐/IL-2诱导肿瘤患者外周血γδT细胞增殖的作用

目的探讨药物（含氮二膦酸盐联合IL-2，N-BP／IL-2）诱导实体肿瘤患者外周血γδT细胞增殖作用。方法采用流式细胞仪测定103例肿瘤患者和43例健康人外周血总T细胞绝对值、御细胞绝对值和相对值，测定患者外周血经药物体外刺激后御细胞增殖指数和用药前后患者外周血总T细胞、γδT细胞绝对值和相对值。结果肿瘤患者和健康人外周血总T细胞绝对值、御细胞绝对值和御细胞相对值的中位数，分别为1306细胞/μl和1522细胞/μlP=0．003），64细胞/μl和162细胞/μl（P〈0．001），5％和11％（P〈0．001）。24例经药物体外扩增试验阳性的肿瘤患者治疗前后体内外周血总T细胞绝对值、γδT细胞绝对值和御细胞相对值的中位数，分别为1283细胞/μl和1552细胞/μl（P=0．001），54细胞/μl和107细胞/μl（P〈0．001），6％和8％（P=0．008）。全部肿瘤患者中外周血γδT细胞对药物体外诱导增殖反应阳性患者的百分率为68．9％。结论肿瘤患者外周血γδT细胞计数显著低于健康人。不同肿瘤患者外周血γδT细胞对药物刺激增殖的反应性不同。N-PB／IL-2在体内有显著增加御细胞数量的药理作用。体外增殖试验可作为N-PB／IL-2治疗患者的参考。     

Interaction of biodegradable β-whitlockite ceramics with bone tissue: An in vivo study

The biodegradation of different porous β-whitlockite materials are studied by in vivo experiments, radiographie follow-ups and light microscopy observations. The materials were implanted in rabbit tibiae for 16 mnth. Micropores play an important role in the biodegradation rate. The resorbing materials evoke an inflammation with plasma cells. The resorption starts in the medulla, and the phagocytosed particles are removed to the lymph nodes. Normal bone function can be restored after all the implant material is resulted.     

细胞内外膜跨膜电位频率响应模型及滤波器特性的研究

提出球形单细胞内外膜跨膜电位频率响应模型和仿真计算方法。通过对频率响应的仿真分析，发现内外膜跨膜电位分别表现出一阶带通和低通滤波器特性，并在内膜频率响应中心频率到上限截止频率的范围内，内膜跨膜电位大于外膜同时能保持在较高水平，这将有利于诱导细胞内电处理效应。计算结果与动物实验吻合得很好，为纳秒脉冲电场治疗肿瘤的窗口参数合理选择提供了理论依据。     

纳秒级陡脉冲电场诱导癌细胞凋亡的实验及作用机理研究

观察纳秒级陡脉冲电场诱导人浆液囊腺性卵巢癌SKOV3癌细胞凋亡效应,及其对细胞内钙离子浓度即[Ca2＋]i的影响并探讨其作用机理。采用场强为10kV/cm、脉宽为100ns、重复频率为1Hz的纳秒级陡脉冲电场作用于SKOV3癌细胞悬液5min。4h后采用Annexin V-FITC/PI双标记并结合流式细胞仪分析SKOV3癌细胞的凋亡率,采用扫描和透射电子显微镜观察癌细胞凋亡的超微结构变化;以Fluo-3/AM为细胞内钙离子的荧光指示剂,用激光扫描共聚焦显微镜检测纳秒级陡脉冲电场对SKOV3癌细胞[Ca2＋]i的影响,及[Ca2＋]i变化时的Ca2＋来源。结果显示,流式细胞术检测到癌细胞的早期凋亡率为（22.21&#177;2.71）%,明显高于对照组的（3.04&#177;0.44）%（P〈0.01）,扫描和透射电子显微镜均观察到典型的凋亡细胞形态,证实纳秒级陡脉冲电场能够有效诱导SKOV3癌细胞发生凋亡;同时纳秒级陡脉冲电场可明显升高细胞[Ca2＋]i（P〈0.01）,而与细胞外钙离子浓度无关（P〉0.05）。由于纳秒级陡脉冲电场的等值频率很高,容易穿透细胞膜,其诱导凋亡的机制之一可能是通过激活细胞内钙库（内质网、线粒体）,引起细胞内钙离子升高,从而介导凋亡信号通路。     

Callus characteristics following intramedullary nailing with stainless steel or epoxy-carbon nails

Summary Biological mechanical improvements of osteosynthesis make intramedullary nailing an attractive alternative to bone plate fixation. However, little is known about stress shielding induced by intramedullary implantation of a nail. To evaluate the effect of the nail rigidity on bone healing, mid-metatarsal osteotomies were performed in sheep and fixed with either stainless steel or epoxy-carbon composite V-shaped nails. Mechanical and histomorphometric features of the callus were evaluated 4 months postoperatively. No statistical difference between the two groups were demonstrated for either mechanical or microstructural characteristics. The presence of a fibrous membrane filling the bone/nail interface and allowing sliding micromotions of the implants and the much smaller effect of nail rigidity, as compared to bone plate after implantation, were assumed to be the main reason for this uniformity. At this stage of healing, bone characteristics were more related to a non-specific (vascular) bone remodeling phenomenon than to a stress-shielding effect.

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Zusammenfassung Biologische und mechanische Fortschritte auf dem Gebiet der Osteosynthese lassen die Marknagelung zu einer attraktiven Alternative zur Plattenosteosynthese wurden. Es ist jedoch wenig bekannt über die Abschirmung des Knochens gegenüber der mechanischen Beanspruchung durch die Implantation eines Marknagels. Um den Einfluß der Steifigkeit des Nagels auf die Knochenheilung zu überprüfen, wurden beim Schaf Metatarsalosteotomien in Schaftmitte durchgeführt und entweder mit einem rostfreien Stahlnagel oder mit einem Epoxy-Kohlenstoff-Nagel mit V-Profil stabilisiert. Mechanische und histomorphometrische Eigenschaften des Knochens wurden 4 Monate postoperativ ermittelt. Für beide Gruppen wurden bei den mechanischen und mikrostrukturellen Befunden keine statistisch signifikanten Unterschiede gefunden. Für these Überein-stimmung wurde eine fibröse Membran in der Kontaktfläche zwischen dem Marknagel und dem umgebenden Knochengewebe, die feine Bewegungen des Implantates erlaubt, verantwortlich gemacht. Ein wesentlich geringerer Effekt wurde der Steifigkeit des Nagels im Vergleich zu einer Plattenosteosynthese beigemessen. In diesem Heilungsstadium waren die Befunde am Knochen mehr mit einer unspezifischen (vaskulären) Umbaureaktion als mit einer Abschirmung gegenüber mechanischer Beanspruchung in Zusammenhang zu bringen.

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Abbreviations M bending moment - D bone outside diameter - y distance nail edge-global center of inertia - I _xxB bone moment of inertia - I _xxN nail moment of inertia - _B maximal bending stress in bone - _N maximal bending stress in the nail Supported in part by grant no. 79-0162 from DGRST     

胺碘酮合用小剂量β受体阻滞剂治疗老年阵发房颤临床观察

目的 比较胺碘酮与小剂量β受体阻滞剂合用对老年阵发性房颤的疗效。方法 回顾分析30名老年阵发房颤患者,根据房颤复律后维持用药的不同,分为3组：单用胺碘酮组（n=11);单用β阻滞剂组（n=9);胺碘酮与小剂量β阻滞剂合用组（n=10)。比较3组患者用药后12个月中房颤控制情况及心室率、心脏传导情况。结果 单用胺碘酮组显效率54．5％,有效率45．5％,无效率0％;单用β受体阻滞剂组显效率22．2％,有效率44．5％,无效率33．3％;胺碘酮与小剂量β受体阻滞剂合用治疗房颤,显效率90％,有效率10％,其疗效明显优于单用胺碘酮（P＜0．05）或单用β阻滞剂（P＜0．01）组,且未见明显副作用：3组间心室率未见显著差别。结论 胺碘酮与小剂β受体阻滞剂合用可有效地控制老年阵发性心房纤颤的发作。     

喉癌中EGFR基因扩增、表达及临床意义

目的研究喉癌中表皮生长因子受体(EGFR)基因的扩增、表达,探讨其在喉癌发生、发展中的作用及临床意义。方法采用差异PCR(differential PCR)方法检测40例喉鳞状细胞癌及配对癌旁正常组织中EGFR基因的扩增(即基因拷贝数增加);应用RT-PCR方法检测EGFR mRNA水平;应用SPSS13.0软件对数据进行统计学分析。结果喉癌组织中有13例(占32.5%)EGFR基因拷贝数增加,癌旁对照组中则未检测到(χ2=15.537,P<0.005);喉癌组织中EGFR mRNA平均积分光密度为872.356±62.340,癌旁对照组为346.425±57.380(t=5.959,P<0.001);喉癌组织分化程度越低,病理分期越晚,EGFR基因扩增和mRNA表达水平越高(P<0.05)。结论喉癌中EGFR基因在DNA水平上的扩增是EGFR mRNA过表达的原因之一,EGFR的扩增和过表达在喉癌的发生、进展中发挥一定作用。