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41.
Aim:  To determine if IgA is required for protection against Chlamydia infection in the male reproductive tract (MRT).
Materials and Methods:  Male polyimmunoglobulin receptor knockout mice (PIgR-/-) and wild-type C57BL/6 (WT) mice were immunised intranasally with chlamydial major outer membrane protein (MOMP) and cholera toxin (CT). MOMP-specific IgG and IgA in serum and prostatic fluids were measured by ELISA. Serum and PF were also assayed for inhibition of in vitro chlamydial infection. Immunized WT and PIgR-/- mice were challenged by direct inoculation of C. muridarum into the meatus urethra. Four weeks post challenge Chlamydia levels in the penile urethra, epididymis and testis were determined by PCR.
Results:  Equivalent levels of IgG were found in the serum of both WT and PIgR-/- mice however IgA in serum of PIgR-/- mice was 19- to 20-fold higher than in WT animals consistent with the lack of the PIgR IgA transport molecule. IgA levels were significantly lower in PIgR-/- PF compared to WT PF after both immunization and infection. Only PF from WT but not PIgR-/- animals was able to inhibit in vitro chlamydial infection. Following challenge significantly higher levels of Chlamydia were recovered from the MRT of PIgR-/- mice compared to WT animals.
Conclusions:  Male mice lacking a functional PIgR were unable to clear a genital tract Chlamydia infection despite high levels of serum IgA. These data show that mucosal IgA plays a major role in preventing chlamydial infection of the male genital tract and suggest that immunization strategies to protect males should target a strong mucosal IgA response.  相似文献   
42.
目的:目前有关骨髓间充质干细胞向内皮细胞诱导分化的研究较少。本实验分离和培养人骨髓间充质干细胞,用带有VEGF165的质粒转染人骨髓间充质干细胞,探讨血管内皮生长因子对其体外诱导分化的作用。 方法:实验于2005—04/2006—04在吉林大学人兽共患病教育部重点实验室完成。取成人的已排除血液系统肿瘤疾病的新鲜骨髓(自愿提供),采用Percoll梯度分离培养骨髓间充质干细胞,于倒置显微镜下观察细胞形态变化和生长情况。原代细胞培养至增殖接近融合状态时,单克隆培养法分离传代培养,扩增骨髓间充质干细胞。采用流式细胞术检测细胞免疫学表型。在原核细胞大肠杆菌DH5α中复制扩增和提取,纯化、克隆pcDNA3.0-VEGF165质粒。用脂质体转染法转染骨髓间充质干细胞:应用流式细胞术检测诱导后骨髓间充质干细胞免疫学表型变化j并采用免疫荧光染色鉴定转染情况,并设质粒空载和未转染的骨髓间充质干细胞为对照。 结果:人骨髓间充质干细胞原代培养1周后,造血细胞消失,贴壁细胞体积增大,呈现梭形外观,有粗大的细胞突起伸出。2周后细胞融合成单层,梭形突起变长,排列有明显的方向性,细胞排列成旋涡状、网状、辐射状。流式细胞术显示,人骨髓间充质干细胞免疫学表型CD44、CD29阳性,CD34、CD31、CD45阴性。VEGF165诱导骨髓间充质千细胞后CD44表达明显降低,CD31明显升高。免疫荧光染色显示,用FITC标记后的VEGF抗体使细胞显现绿色荧光,用cy3标记的CD31抗体使细胞显现了红色荧光。 结论:转染后的骨髓间充质干细胞细胞表型发生明显转变,CD31表达率明显增高,呈现典型的内皮细胞的表型特征,这说明骨髓间充质干细胞具有向内皮细胞分化的潜能。  相似文献   
43.
Aspirin in acute gastroenteritis: a clinical and microbiological study   总被引:2,自引:0,他引:2  
Soluble aspirin given by mouth in divided dosage decreased intestinal fluid loss in infants and young children with acute gastroenteritis. The treated group had significantly less diarrhea, which ceased earlier and needed less intravenous therapy, than a randomly selected control group given an indistinguishable placebo. This effect of aspirin occurred with diarrhea caused by Salmonella, Aeromonas, Escherichia coli producing heat-labile toxin, and rotavirus, but not with diarrhea associated with strains of E. coli producing heat-stable toxin.  相似文献   
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The reactivation of mycobacterium infection inrenal transplant recipients in developingcountries is a common therapeutic dilemma,especially in those patients receivingcyclosporin immunosuppression. The inclusion ofrifampicin in the antituberculosis protocolincreases the risk of precipitating acuteallograft rejection due to its interaction withcyclosporin and also increases the financialburden. We successfully treated 16 patients whodeveloped mycobacterial infection post renaltransplant with a rifampicin sparingantituberculosis drug regimen. Pyrexia ofunknown origin was the most common manifestationobserved and a therapeutic trial withantituberculosis drugs is justified. De novodiabetes mellitus appears to be an added riskfactor and increases the susceptibility tomycobacterial infection.  相似文献   
46.
Suprasellar dermoid cysts are uncommon intracranial lesions. CT and MRI findings in a rare case of asymptomatic rupture of suprasellar dermoid cyst with subarachnoid dissemination is described.  相似文献   
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OBJECTIVES: Provide reference for surgeon and pathologist regarding expected yield from selective neck dissections. Quantify lymph nodes obtained from cadaver dissection based on current nodal classification and compare with clinical series. STUDY DESIGN: 1. Quantification of lymph nodes at levels I-V harvested from human cadavers and correlation with nodal grouping for supraomohyoid (I-III) and lateral (II-IV) neck dissections. 2. Retrospective review of operative specimens from clinical neck dissections for lymph node quantity. METHODS: 1. Twenty radical neck dissection specimens, harvested from 10 fresh human cadavers without evidence of head and neck cancer, were separated by nodal level for gross and microscopic examination by a pathologist. The quantity of nodes obtained per level for each specimen was tabulated. 2. Charts of patients treated with neck dissection for squamous cell carcinoma were reviewed and tabulated for type of dissection and number of lymph nodes reported. RESULTS: In the 20 cadaver neck dissections, the average number of lymph nodes removed for levels I-V was 24, with 13 for levels I-III and 19 for levels II-IV. In the clinical review, 98 total neck dissections were included. In the six supraomohyoid dissections, an average of 20 lymph nodes (range, 14-26) were found, with an average of 30 (range, 15-43) in the 11 lateral compartment specimens. In 81 radical or modified radical dissections, an average of 31 nodes (range, 19-63) was reported. CONCLUSIONS: The number of lymph nodes removed in selective neck dissection should be comparable to that of the corresponding levels in radical neck dissection, provided that strict adherence to surgical boundaries is maintained. Dissection of normal cadavers provides a reference for the surgeon and the pathologist but may under-represent lymph node quantity in the diseased state.  相似文献   
50.
Research has shown that anticonvulsants are teratogens and pose a risk for fetal malformations. Though Fetal Hydantoin Syndrome (FHS) was first reported by Langhman and others, wide phenotypic variability of this syndrome has lead many clinicians to question its very existence. We report a twelve year old girl with FHS with rheumatic valvular heart disease.  相似文献   
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