β型钛合金材料的生物相容性评价

背景:前期大量研究证实钛及钛合金具有良好的生物相容性和较强的耐腐蚀性,β钛合金以其高机械强度、低弹性模量,使其成为目前最具有吸引力的金属生物医学应用材料。目的:评价两种新型β型钛合金材料TLE(Ti-(3～6)Zr-(2～4)Mo-(24～27)Nb),TLM2(Ti-(1.5～4.5)Zr-(0.5～5.5)Sn-(1.5～4.4)Mo-(23.5～26.5)Nb)的生物相容性。方法:取健康成年新西兰兔30只,随机抽签法分为皮下植入组和肌肉植入组。将2种新型钛合金TLE、TLM2加工成圆柱形实验试件,分别植入家兔大腿皮下和背侧肌肉内。对照材料(Ti-6Al-4V)同法植入同一动物的对侧相同部位。依据GB/T16886.6-1997标准,在1,2,6,12,24周取标本大体观察纤维包膜的形态,光学显微镜下观察皮下和肌肉组试件与周围组织界面反应情况,苏木精-伊红染色进行组织学观察。结果与结论:植入2,6,12,24周后,试件周围均形成了血管化的包膜,随着植入时间的延长包膜逐渐变薄、透明度增高,包膜内毛细血管的数量增加。肌肉植入组包膜厚度在6,12周时比皮下植入组薄,炎细胞主要是中性粒细胞、巨噬细胞、多核巨细胞、淋巴细胞和浆细胞,随着时间的延长,各类炎细胞的数量逐渐减少,12周后中性粒细胞数量明显减少,淋巴细胞和浆细胞随时间延长数量逐渐变少,24周时均未见中性粒细胞。说明TLE,TLM2新型医用钛合金生物相容性好,具有良好的临床应用前景。     

纳米羟基磷灰石膜聚氨酯复合材料的体内组织相容性

背景：纳米羟基磷灰石与聚氨酯复合材料在体外实验中具有良好的相容性。 目的：验证纳米羟基磷灰石膜聚氨酯复合材料在大鼠体内的组织相容性。 方法：将18只SD大鼠随机分为复合材料组、聚氨酯组和对照组,复合材料组和聚氨酯组分别将纳米羟基磷灰石膜聚氨酯复合材料、聚氨酯植入大鼠背部肌肉内,对照组仅作切开缝合,未植入任何材料。 结果与结论：①大体观察：术后12周,各组切口与周围皮肤几乎无界限,聚氨酯组及复合材料组囊壁与材料融合较好,对照组皮肤已恢复正常。②组织学观察：术后4,8,12周,聚氨酯组及复合材料组切口周围组织中淋巴细胞数、中性粒细胞数及毛细血管量均高于对照组(P < 0.05),复合材料组切口周围组织中淋巴细胞数、中性粒细胞数及毛细血管量均少于聚氨酯组(P < 0.05)。证实纳米羟基磷灰石膜聚氨酯复合材料具有较好的组织相容性。     

组织工程化纳米细菌纤维素管体内生物相容性研究

通过肌肉植入试验,初步探讨组织工程化纳米细菌纤维素管的体内生物相容性.利用茶水发酵法培养红茶菌,制备纳米细菌纤维素并使之成管,扫描电镜观察其表面结构.将消毒后的纤维素管植入大鼠大腿肌肉内贴近坐骨神经处,分别于第1、2、6周各随机抽取6只大鼠灌流固定、取材,做大体观察、组织学观察及血液学检查.扫描电镜观察显示,细菌纤维素管壁由细菌纤维素条相互交织,形成不规则的、疏松的网状或絮状多孔结构.材料植入后第1周,可见材料周围有较厚的结缔组织包裹,与周围组织粘连较明显,光镜下有较多的中性粒细胞和少量的单核细胞、淋巴细胞浸润,同时周围肌肉组织炎症细胞浸润明显,以中性粒细胞为主;植入后第2周结缔组织包裹明显缩小,管壁周围的炎性反应明显减轻,以中性粒细胞、淋巴细胞为主,周围肌肉组织的炎性反应亦明显减轻,同时偶可见嗜酸性粒细胞和巨噬细胞;植入后第6周,材料与周围组织分界清楚,仍然有结缔组织包裹,炎细胞数量明显减少,以淋巴细胞为主,周围肌肉组织未见明显炎症细胞浸润,同时材料开始轻度降解.血常规和血生化指标检测显示,各时间点与正常大鼠数据间的差异无统计学意义.组织工程化纳米细菌纤维素管在短期观察中,具有良好的体内生物相容性.     

掺锶硫酸钙复合骨修复材料体内组织相容性研究

目的初步验证掺锶硫酸钙复合骨修复材料的体内组织相容性旨在为后续的进一步研究提供基础。方法取含锶量为0．5％的掺锶硫酸钙材料,采用新西兰兔背脊肌内植入模型。分别于手术后1周,2周,4周,8周四个时间点各处死3只兔子取材。HE染色,光镜观察细胞和肌肉组织的形态学变化。植入材料周围组织冰冻切片（厚度约51am）。选择细胞色素氧化酶（CCO）和乳酸脱氢酶（LDH）两种2种主要细胞器的标志酶进行酶组织化学染色。镜下观察得出计数资料,整理成等级资料。染色强度分为4个等级：阴性（O）,阳性（1）,强阳性（2）,和极强阳性（3）。结果所有实验动物术后1～3小时恢复活动,1天后进食正常。实验动物伤口均一期愈合。组织学结果显示掺锶硫酸钙材料植入1w后,植入体周围组织内有较多中性粒细胞浸润,由成纤维细胞组成厚薄不均、结构疏松的纤维囊壁。随着植入时间的延长,材料周围组织的炎症反应逐渐消失,炎细胞浸润越来越少,包膜先变厚再变薄,纤维包囊较薄。术后8w,植入体周围组织内未见炎性细胞浸润,纤维囊腔壁进一步变薄,主要成分为胶原纤维和成纤维细胞。其组织学改变与对照材料α-半水硫酸钙相比无明显区别。酶组织化学染色结果显示掺锶硫酸钙组植入材料周边肌细胞在1w时CCO和LDH活性均减弱（P〈0．05）,2w时CCO和LDH活性均恢复正常（P〉0．05）,其后活性无明显变化（P〉0．05）。掺锶硫酸钙组与a．CSH组和单纯创口组之间两两比较无明显差异（P〉0．05）。结论掺锶硫酸钙复合骨修复材料对体内组织细胞无毒性作用,具有与α-CSH相似的良好体内组织相容性。     

LH750血细胞分析仪检测妊娠期白细胞参数

目的探讨LH750血细胞分析仪检测妊娠期白细胞参数。方法采用LH750血细胞分析仪,检测100例健康妊娠期妇女和37例健康育龄妇女的白细胞总数（WBC）、中性粒细胞（NE）,淋巴细胞（LY）,单核细胞（MO）,嗜酸性粒细胞（EO）及嗜碱性粒细胞（BA）的百分比及绝对值等相关21项白细胞参数。结果妊娠组与正常对照组比较：NEC、NES、LYV、LYC、MOV和MOC与对照组均无明显差异,P〉0.05,无统计学意义。其余各白细胞参数与对照组有差异,P〈0.05,有统计学意义。结论妊娠者中性粒细胞（NE）增加并伴随VCS参数发生较大改变,应考虑其合并感染的可能性。     

医用级高温硫化甲基乙烯基硅橡胶长期植入的病理学观察(摘要)

硅橡胶是应用最广、效果最为显著的一种医用高分子材料。笔者对国产医用级热硫化甲基乙烯基硅橡胶作了长期家免肌肉与子宫内植入的病理学研究,实验结果如下: 被检家兔肌肉包埋15天后,材料与组织接触部位见有少量嗜中性粒细胞和淋巴细胞浸润,并偶尔可见零星的异物巨细胞反应及嗜酸性粒细胞,同时在材料周围还可见新生毛细血管与纤维母细胞增生,开始形成疏松囊腔结构     

组织工程骨-假体界面微观结构与元素分析的意义

目的研究假体-组织工程骨界面的微观结构和钙磷元素及构成比动态变化及意义。方法取新西兰大白兔15只,将兔骨髓间充质干细胞培养、扩增及诱导后,与珊瑚羟基磷灰石复合构建组织工程骨;双侧股骨髁分别制作一0.5cm×1.2cm骨缺损,骨缺损中央植入0.2cmx1.0cm钛合金植入体,左侧植入体周围植入组织工程骨,右侧仅植入珊瑚羟基磷灰石为对照,于术后4周、8周和l2周分别行X线检查、扫描电镜及能谱分析观察植入体表面微观结构和钙磷元素百分含量及比值的变化。结果 X线检查示,实验组术后8-12周可见大量模糊的高密度骨痂影,缺损区与周围骨质间分界变模糊。对照组各时间点无明显变化;扫描电镜示,实验组术后8、12周植入体表面孔隙内有大量无定形物质,而对照组未见有无定形物质。能谱分析示,不同时间点实验组较对照组内钙、磷元素百分含量高,有显著性差异（〈0.05）,随着时间的变化实验组和对照组Ca、P百分含量都呈增高的趋势,但12周和8周相比无显著性差异（〉0.05）。实验组内钙磷比值随时间变化有逐渐增大趋势,8周时达峰值,8周后缓慢下降。结论假体-组织工程骨界面钙、磷元素及构成比的动态变化表明骨整合的形成,并随着时间的延长骨改建逐步增加。     

母鼠孕前营养过剩对子代小鼠生长发育影响

目的构建孕前营养过剩及超重小鼠模型,探讨孕前营养过剩对子代小鼠生长发育影响。方法 20只昆明种雌鼠随机分为对照组和实验组,分别给予标准饲料和高脂高糖饲料;两组单纯饲养4周后与雄鼠合笼,孕期继续上述饮食;产后均母乳喂养,产后3w断乳,哺乳期间母鼠仍按各自组别进食;监测单纯饲养期、孕期和哺乳期母鼠体重、血糖变化。两组子鼠断乳后一律以标准饲料喂养,监测子鼠出生至生后5w体重、身长和尾长发育。结果 1.母鼠体重和血糖变化：单纯饲养1周后开始实验组母鼠体重持续显著高于对照组（P〈0.05）;饲养1w和4w时,实验组母鼠血糖显著高于对照组（P〈0.05）。孕中、晚期实验组母鼠体重与对照组无显著差异（P〉0.05）。哺乳期两组母鼠体重、血糖均无显著差异（P〉0.05）。2.母乳喂养期子鼠发育：出生3天和7天,实验组子鼠体重显著高于对照组（P〈0.05）;整个母乳喂养期,实验组子鼠尾长显著长于对照组（P〈0.05）,两组子鼠身长无显著差异（P〉0.05）。3.自由采食期子鼠发育：整个自由采食期,实验组雌性子鼠体重显著高于对照组（P〈0.05）;出生35天,实验组雄性子鼠体重也显著高于对照组（P〈0.05）;整个自由采食期,实验组子鼠尾长均显著长于对照组（P〈0.05）,两组子鼠身长无显著差异（P〉0.05）。结论通过高脂高糖饲料可以建立孕前营养过剩及超重小鼠模型,母鼠孕前营养过剩导致子代小鼠出生体重增加以及成年早期肥胖,其对机体的深入影响及机制值得进一步研究。     

大鼠羊水栓塞后类胰蛋白酶、TNF-α水平变化的研究

目的探讨类胰蛋白酶、TNF-α在羊水栓塞中的变化及病理生理作用。方法精选雌性鼠30只于妊娠20天制作羊水栓塞模型。根据注入液体性质不同随机分为对照组（10只）、羊水组（10只）、胎粪液组（10只）。对照组除注入生理盐水外,皆同其余组。实验后取鼠左肺行H.E染色光镜下观察,采用专性底物对模型鼠的血清类胰蛋白酶酶活力进行测定。免疫法检测血中肿瘤坏死因子（TNF-α）含量。结果 1.实验组肺组织可见大量炎性细胞浸润,包括白细胞（主要为中性粒细胞）、巨噬细胞及少量淋巴细胞。2.生理盐水组注入前后类胰蛋白酶水平无明显差异（P〉0.05）;鼠原羊水组和胎粪液组注入后类胰蛋白酶水平明显升高,差异显著（P〈0.01）。3、实验组中TNF-α含量较对照组高,差异显著（P〈0.01）。结论肥大细胞脱颗粒释放类胰蛋白酶可能是羊水栓塞的重要原因,在此基础上引起中性粒细胞、巨噬细胞浸润及一系列病理变化,由此引起肺损伤及临床症状。该酶学方法灵敏、有效,在羊水栓塞临床早期诊断中有一定的应用价值。     

防暑汤对士兵高温训练前后外周血中HSP72表达及血液生化的影响

目的研究防暑汤对高温训练前后士兵外周血中淋巴细胞热休克蛋白72（HSP72）的表达和血液生化的影响,为防暑药物增强士兵热耐力、预防中暑提供实验依据。方法选取某部普通士兵120人,随机分为两组,每组60人。未饮用防暑汤者为对照组,饮用防暑汤者为实验组。进行高温训练任务的1周内,实验组士兵每日饮用防暑汤300 mL,饮用前及1周后抽取各组外周静脉血,分别进行淋巴细胞HSP72含量、血液常规及生化指标测定。结果饮用前后两组血液常规及生化检测值均在成年男子的正常值范围之内。饮用前,实验组HSP72的表达与对照组比较无显著差异（P〉0.05）;饮用后,实验组HSP72表达显著高于训练前及对照组（P〈0.05）;HSP72表达的增长值,实验组显著高于对照组（P〈0.05）;部分血液常规及生化指标存在显著差异。结论防暑汤能提高士兵受热刺激后表达HSP72的能力,从而起到增强士兵热耐力、预防中暑的作用。     

(Electron) microscopic observations on tissue integration of collagen-immobilized polyurethane

The foreign body reactions to collagen-immobilized polyurethane (PU-CI) films during subcutaneous implantation in rats were characterized. The underlying concept is that collagen-immobilization will improve the tissue integration. Since the method of collagen-immobilization involves the covalent coupling of collagen to an acrylic acid (AA) based surface graft, both non-modified PU and PU-AA were used as controls. Bare PU has a flat surface, whereas both PU-AA and PU-CI displayed a slightly roughened surface. Implantation showed that PU-CI induced early after implantation a far more intense foreign body reaction than PU and PU-AA. This reaction consisted of increased presence of fibrin, granulocytes and macrophages. Roughening of the surface as with PU-AA induced only a small increase in fibrin formation and cellular migration. At day 5 the reaction to PU-CI had slowed down; giant cell formation now slowly started but was decreased compared to PU and PU-AA. At day 10 capsules around each type of material looked similar, but in contrast to PU. PU-CI films could no longer be dissected from their capsules. Only at week 3 this also occurred with PU, at which time point again similar capsules with the three materials were observed. At week 6, of the three materials PU-CI showed the thinnest capsule with most immediate adherence of connective tissue. These results show that collagen-immobilization of PU increased the early tissue reaction and therefore the tissue integration. The thin capsule observed at 6 weeks may be beneficial in e.g. infectious circumstances, when easy access for immune reactions is needed. This, and the long-term performance of PU-CI will be a matter of future investigations.     

pH-stabilization of predegraded PDLLA by an admixture of water-soluble sodiumhydrogenphosphate--results of an in vitro- and in vivo-study

Aim of the study was to examine if the addition of buffering sodiumhydrogenphosphate to poly(D,L)lactide(PDLLA) would stabilize the pH-value in the in vivo environment of implanted material and whether this improves its biocompatibility. The material was predegraded just to the point of viscous disintegration to test the PDLLA in the moment of its most aggressive effect on the surrounding tissue. Racemic amorphous PDLLA was injection-molded with or without the admixture of 1 mol NaP per 100 mol lactate, the degradation product of PDLLA (=1 mol%) to form 20mm x 3 mm x 2mm rods. Predegradation was performed by storing the rods at 55 degrees C for 14 days, just to the point of beginning dissolution. Predegraded PDLLA or PDLLA + NaP samples were used for in vitro incubation tests, as well as for the in vivo study, where the rods were implanted into the spinal muscles of 30 male Wistar rats. Repeatedly, measurements of the pH-value were made in the incubation solutions in vitro. The surrounding tissue of the implanted samples as well as the normal contralateral muscle tissue was checked for its pH-value in a group of 3 rats, respectively, anaesthesized at various time intervals after implantation. After these measurements the implants and their surrounding tissues were excised for histological examination. In Ringer's solution pH-values dropped immediately within the first week of incubation of both predegraded materials reaching -4 pH units after 4 weeks in the PDLLA containing medium, after 6 weeks in the PDLLA + NaP containing medium. Soerensen buffer slowed the pH decrease with significant differences between the material groups up to the 28th week. In vivo, the pH of the surrounding tissue was influenced by the implanted PDLLA material up to the 4th week, while the admixture of NaP resulted in a significant pH stabilization. A higher quantity of macrophages and giant cells were seen between the 2nd and 6th week after the implantation in the environment of pure PDLLA compared with PDLLA + NaP. Complete resorption of predegraded pure PDLLA or PDLLA + NaP from the extracellular space was reached 28 weeks postimplantation in vivo. Thus, sodiumhydrogenphosphate improves the biocompatibility of degrading PDLLA at the point of viscous disintegration by stabilizing the pH-value in the environment of the implants for several weeks and reducing adverse tissue reactions.     

Comparison of the effect of autologous and homologous injections of vitreous body with Hyalgan into the knee joint of the rabbit as an animal model

The histopathological properties of vitreous body have not yet been well clarified. This study compares the histopathological effects of autologous and homologous injections of vitreous body with Hyalgan into the knee joint of a rabbit. Thirty-six white New Zealand rabbits were divided into three equal groups. Under anesthesia and sterile conditions, rabbit vitreous body was obtained through the clear corneal incision with a trephine after lens delivery. In the first group, 0.5?ml of vitreous body was autologously injected into the rabbit's knee. In the second group, homologous vitreous body from one rabbit was injected into the left knee of another rabbit. In the third group, 0.5?ml of sodium hyaluronate (Hyalgan) was similarly injected into the rabbit's knee. Twelve rabbits were considered as control group and received just normal saline. Each group was subdivided into two groups, A and B. The rabbits' articular cartilages and synovial membranes were histologically investigated for any inflammation after 1?week for group A and after 12?weeks for group B. After 1?week, no significant difference was found between the autologous and homologous vitreous body and Hyalgan injection groups. In comparison with the control group, no significant histological differences were noted. After 3?months, in both homologous and autologous vitreous-treated groups, no signs of chronic inflammation were noticed. However, in the Hyalgan group, there were signs of mild synovial hyperplasia, moderate infiltration of lymphocytes, and mild increased vascularity without any signs of fibrosis. It seems that vitreous body can be a safe and proper substitute for Hyalgan to be injected into the joint space.     

The influence of training-detraining upon the heart, muscle and adipose tissue of female rats.

The purpose of this study was to measure the effects of a 10 week training, 3 week detraining cycle upon heart, muscle and adipose tissue of the rat. Specific pathogen-free female Wistar rats, 175 g at the onset of the experiments, were separated into three treatment groups; Sedentary Control (SC), Trained (T) and Detrained (DT). Animals from the T group were killed at 2, 4, 6, 8 and 10 weeks and animals from the DT group were killed at 7, 14 and 21 days after the last day of training. Unweighted swimming--6 h/day, 5 day/week, was the form of training employed. The animals, after being sacrificed, were anesthetized with nembutal (45 mg/kg body wt.) and muscle samples and heart removed. These tissues were frozen and analyzed at a later date for succinate dehydrogenase (SDH) activity (muscles), total protein (TP), total hydroxylprotein (TH) and wet and dry weight (heart). Adipose tissue was removed last, digested in collagenase (5 mg/ml) and the isolated cells used to measured 2-[3H]deoxyglucose uptake (DOG) and the conversion of D-[1-14C]glucose (C-1) and D-[6-14C]glucose (C-6) to CO2. The results of this study show that 10 weeks of endurance training induced myocardial hypertrophy (P less than 0.05) which involved increases in both TP and TH, the heart of the trained animals having 20.8% more protein and a 28.5% more hydroxlprotein than the sedentary controls. With detraining hypertrophy was lost within 21 days. Training maintained fat cell size at its pre-trained diameter, while inactivity allowed growth in the adipocytes of the control animals. The uptake of DOG and the conversion of glucose C-1 and glucose C-6 to CO2, were significantly (P less than 0.05) higher in the adipocytes of trained animals indicating that they were more responsive to insulin than the sedentary controls, which corresponded to increases in the respiratory enzyme levels of the muscles. During the first 7 days of detraining DOG uptake and both C-1 and C-6 glucose oxidation remained elevated. In conclusion the results of this study clearly demonstrate that there is a direct relationship between adiposity and training that can be related to the insulin responsiveness of the adipose tissue.     

多孔型丝素蛋白/羟基磷灰石复合骨髓间充质干细胞修复兔半月板无血运区软骨损伤

背景：随着组织工程的兴起,半月板无血运区损伤的修复可能性显著地提高,但单一的支架材料均不能符合理想支架的要求,有一定的局限性。 目的：观察丝素蛋白/羟基磷灰石复合骨髓间充质干细胞修复兔半月板无血运区软骨损伤的效果。 方法：体外分离培养兔骨髓间充质干细胞,并定向诱导成纤维软骨细胞,与丝素蛋白/羟基磷灰石复合培养。42只构建半月板无血运区软骨损伤模型成功的大白兔随机抽签法均分为3组,复合材料组植入骨髓间充质干细胞-丝素蛋白/羟基磷灰石复合物;单纯材料组植入丝素蛋白/羟基磷灰石;对照组不行任何干预。 结果与结论：复合材料组大体观察损伤被修复组织填充,8~12周效果逐渐改善,与正常半月板组织相似,优于其他两组;组织学检查显示8周时出现软骨囊和排列紊乱的胶原纤维,12周时完全修复了半月板损伤区,表现为纤维软骨样组织愈合;单纯材料组部分修复了半月板损伤区,呈瘢痕愈合,对照组未见软骨修复。MRI检查显示复合材料组修复效果较好;说明丝素蛋白/羟基磷灰石复合骨髓间充质干细胞可有效地修复半月板无血运区缺损。丝素蛋白/羟基磷灰石材料作为半月板软骨组织工程支架材料的良好生物相容性。     

聚碳酸亚丙酯/壳聚糖纳米纤维三维多孔支架复合骨髓间充质干细胞修复兔骨缺损

背景：骨组织工程细胞移植技术是近年来的研究热点,支架材料是其重要组成部分,同时也是三大要素中最有望取得突破性进展的环节,随着组织工程材料工艺的革新,有望为更好地修复骨缺损带来新的希望。 目的：评价聚碳酸亚丙酯/壳聚糖纳米纤维(propylene carbonate/chitosan nanofibers,PPC/CSNF)三维多孔支架复合骨髓间充质干细胞(bone marrow mesenchymal stem cell,BMSCs)修复兔股骨髁部骨缺损的能力。 方法：二次相分离法制作PPC/CSNF复合三维多孔支架,将第3代的BMSCs 种植到复合材料上。36只新西兰大白兔右侧股骨髁制作直径6 mm深10 mm骨缺损,于缺损处实验组植入复合BMSCs的PPC/CSNF多孔支架,对照组植入单纯PPC/CSNF多孔支架,标准组于兔髂后上棘取自体松质骨移植于缺损部位,空白组不做处理。术后第4,8,12周取材,通过大体观察、放射学检查和组织学检查等方法评价其修复缺损情况。 结果与结论：实验组放射学评价与标准组无显著差异,两组结果均优于对照组(P< 0.05);实验组大体标本与标准组基本一致;实验组组织学检查新骨生成速度、生成量优于对照组(P < 0.05);空白组不能自行修复骨缺损,最后缺损由纤维组织充填。结果显示PPC/CSNF多孔支架具有较好的细胞和组织相容性,复合兔BMSCs能加速新骨形成,可用于修复兔股骨髁部骨缺损。     

A three-phase, fully resorbable, polyester/calcium phosphate scaffold for bone tissue engineering: Evolution of scaffold design

Bone tissue engineering strategies are fundamentally based upon porous scaffold materials that serve as a support for ingrowth of host cells and/or provide a substrate for exogenously delivered cells. Here we report the application of a surface calcium phosphate (CaP) mineral layer to a macroporous polymeric/CaP composite biomaterial, with a macroporous interconnectivity, and its subsequent in vivo evaluation in a rodent femoral defect. The application of the mineral layer eliminates the fibrous tissue encapsulation and foreign body giant cell response commonly seen at the interface of polymeric materials, yet retains the unique characteristics of the parent material as being macroporous, completely biodegradable and possessing a high degree of interconnectivity. This represents the third generation of this scaffold material, incorporating iterative changes to the scaffold design in response to both materials and biological design criteria to produce a material with enhanced in vitro and in vivo performance.     

肺炎克雷伯杆菌感染引起大鼠小气道炎症的免疫学特征

本文观察了肺炎克雷伯杆菌气道感染引起大鼠小气道炎症细胞和肺组织中TNF α含量动态变化。结果显示 ,肺炎克雷伯杆菌感染第 1天至第 1周 ,小气道壁中炎症细胞以中性粒细胞增多为主。感染第 2周至第 16周 ,小气道壁T淋巴细胞较对照组明显增多 (P <0 0 1) ,其阳性细胞百分率范围在 39%～ 67%。感染第 8周和第 16周 ,小气道壁CD4/CD8比值下降 ,分别为 0 5 7和 0 41,同时间对照组为 0 75和 0 78。树突状细胞 (S 10 0阳性细胞 )分布在小气道上皮 ,固有膜和粘膜下层。感染第 1周至第 8周 ,肺组织中TNF α含量明显升高 (P <0 0 1)。因此 ,在克雷伯杆菌感染引起的小气道炎症中 ,小气道壁T淋巴细胞 ,尤其CD8T细胞浸润值得重视。同时 ,肺组织中TNF α含量增高可能是T淋巴细胞在肺内积聚和数量增多机制之一。     

BMP2活性多肽/PLGA复合物植入异位成骨的实验研究

目的用动物实验的方法评价自行研制合成的BMP2活性多肽生物因子与可降解PLGA复合物的异位诱导成骨能力。方法实验分3组。A组：BMP2活性多肽／PLGA复合物组；B组：单纯PLGA组；C组：明胶海绵组。分别于Wistar大鼠背部两侧骶棘肌下包埋植入。术后1、4、8和12周取材。经组织学观察和CT三维成像比较成骨情况，western blot检测Ⅰ型胶原及骨桥蛋白的蛋白表达，了解异位成骨的情况。结果植入块周围初期均表现为急性炎症反应，后期均为淋巴细胞、巨噬细胞浸润为主的非特异性炎症反应。A组植入4周时植入区有软骨生成，8周时有活跃的成骨细胞出现，并有非编织骨结构。12周可见大量新骨形成，有典型的骨小梁新生血管结构。B组和C组12周时仅见纤维组织形成，未见成骨。结论人工合成的BMP2活性多肽体内能启动软骨化骨过程，具有较强的异位诱导成骨能力。有与天然BMP2类似的骨诱导活性，具有广阔的应用前景。     

Hepatic changes in congenital Schistosoma japonicum infections in pigs

The inflammatory response in liver tissue from piglets congenitally infected with Schistosoma japonicum was examined at two different timepoints after infection. The piglets, which were the offspring of three sows infected with 9000 S. japonicum cercariae in the 10th week of gestation, were allocated into two groups (n=9 and 17) killed 5 or 11 weeks after birth, respectively. All piglets developed a low level infection,with no significant difference between the groups. Inflammatory lesions in the liver consisted mainly of granulomas in portal areas, often obliterating the portal veins, and frequently with central eggs or egg remnants. The granulomatous reaction consisted of epithelioid cells and occasional giant cells surrounded by layers of lymphocytes, eosinophils, plasma cells, and various amounts of collagen and fibroblasts. Mild to moderate infiltration of portal and septal connective tissue with eosinophils and lymphocytes was common, but the connective tissue was generally not increased. At the two timepoints, slight differences were observed in the numbers of eosinophils and lymphocytes in the granulomas and in the size of the granulomatous reaction. The same pattern of immunohistochemical labelling was seen in both groups. CD79alpha(+) B cells were scarce except in granuloma-associated lymphoid follicles;the majority of lymphocytes in granulomas and at other sites were CD3epsilon(+) T cells. The granulomatous reaction in the livers of piglets to schistosoma eggs from prenatal S. japonicum infection was similar to that seen in postnatal infection. Signs of immunomodulation of granulomas between the two timepoints of infection were not demonstrable.