Tumor Necrosis Factor-α Up-Regulates the Expression of β1,4-Galactosyltransferase-I in Human Fibroblast-like Synoviocytes

β1,4-Galactosyltransferase-I (β1,4-GalT-I), which transfers galactose to the terminal N-acetylglucosamine of N- and O-linked glycans in a β1,4-linkage, is considered to be the major galactosyltransferase among the seven members of the subfamily responsible for β4 galactosylation. We previously reported, for the first time, that β1,4-GalT-I may play an important role in the inflammatory processes in synovial tissue of patients with rheumatoid arthritis (RA). In this study, we analyzed whether β1,4-GalT-I expression correlates with the expression of tumor necrosis factor-α (TNF-α) in RA. We show firstly the overexpression and co-localization of β1,4-GalT-I and TNF-α in synovial tissue of RA patients. Then, lipopolysaccharide (LPS) induces β1,4-GalT-I mRNA up-regulation in fibroblast-like synoviocytes (FLSs) through endogenous TNF-α overexpression. In addition, we observed that not only endogenous TNF-α but also exogenous TNF-α induced β1,4-GalT-I mRNA production in FLSs, and TNF-α-knockdown reverses the up-regulation of β1,4-GalT-I in FLSs induced by LPS or TNF-α. These results suggest that TNF-α contributes to the up-regulation of β1,4-GalT-I mRNA in human FLSs.     

抑癌基因p53结合蛋白1基因突变与前列腺腺癌的关系

目的 检测抑癌基因p53结合蛋白1(53BP1)基因突变在前列腺腺癌和良性前列腺增生组织中的发生率,分析53BP1基因突变与前列腺腺癌的相关性.方法 采用基因组DNA抽提、聚合酶链反应(PCR)扩增及基因测序的方法 检测50例前列腺腺癌与10例良性前列腺增生组织中53BP1基因的突变情况.结果 50例前列腺腺癌组织中共检测到15种不同类型的53BP1基因异常,其中4种为正常组织中也检测到的单核苷酸多态性,11种不同类型的突变发生在12例前列腺腺癌组织中,总突变率达24.0%(12/50).11种53BP1基因突变中,7种为错义突变,但均未发生在重要结构域上,另外4种为同义突变,其中c.4760G>T突变位于53BP1 Tudor结构域.53BP1基因突变与前列腺腺癌患者多种临床病理参数均无明显相关性(P>0.05).结论 对前列腺腺癌患者的53BP1基因全长外显子进行突变检测发现有一定比例的基因突变,推测53BP1基因突变与前列腺腺癌的发生有关.

Abstract：

Objective To study the incidence of 53BP1 gene mutations in prostatic adenocarcinoma and benign prostatic hypertrophy, and to analyze the relationship between 53BP1 mutations and prostatic adenocarcinoma. Methods Genomic DNA extraction, PCR amplification and gene sequencing were used to detect the occurrence of 53BP1 gene mutations in 50 cases of prostatic adenocarcinoma. Ten cases of benign prostatic hypertrophy were included as controls. Results Amongst the 50 cases of prostatic adenocarcinoma studied, 15 showed genetic alterations of 53BP1, including 4 cases with single nucleotide polymorphism. The mutation rate was 24.0%(12/50). Seven of the 53BP1 mutations detected represented missense mutations and none of them were situated in functionally important domains. The other 4 were synonymous mutations, in which c.4760G>T was situated in Tudor domain. There was no obvious correlation between 53BP1 gene mutations and the various clinicopathologic parameters of prostate adenocarcinoma(P>0.05).ConclusionCertain percentage of prostatic adenocarcinoma harbors 53BP1 mutations which may be involved in the carcinogenesis.     

p53在蛛网膜下腔出血小鼠脑皮质的表达及其与PI3K/Akt信号通路的关系

目的 探讨p53蛋白在实验性蛛网膜下腔出血小鼠脑皮质的表达及其与PI3K/Akt信号通路的关系.方法 将72只小鼠随机平均分为3组,即假手术组(Sham组),蛛网膜下腔出血组(SAH组),抑制剂LY294002组(LY组).采用线栓法制备小鼠蛛网膜下腔出血模型,术后观测6个时相点:0h、3h、6h、9h、12h、24h...     

Localization of Chlamydia trachomatis hypothetical protein CT311 in host cell cytoplasm

The chlamydia-specific hypothetical protein CT311 was detected both inside and outside of the chlamydial inclusions in Chlamydia trachomatis-infected cells. The extra-inclusion CT311 molecules were distributed in the host cell cytoplasm with a pattern similar to that of CPAF, a known Chlamydia-secreted protease. The detection of CT311 was specific since the anti-CT311 antibody labeling was only removed by absorption with CT311 but not CPAF fusion proteins. In addition, both anti-CT311 and anti-CPAF antibodies only detected their corresponding endogenous proteins without cross-reacting with each other or any other antigens in the whole cell lysates of C. trachomatis-infected cells. Although both CT311 and CPAF proteins were first detected 12 h after infection, localization of CT311 into host cell cytosol was delayed until 24 h while CPAF secretion into host cell cytosol was already obvious by 18 h after infection. The host cell cytosolic localization of CT311 was further confirmed in human primary cells. CT311 was predicted to contain an N-terminal secretion signal sequence and the CT311 signal sequence directed secretion of PhoA into bacterial periplasmic region in a heterologous assay system, suggesting that a sec-dependent pathway may play a role in the secretion of CT311 into host cell cytosol. This hypothesis is further supported by the observation that secretion of CT311 in Chlamydia-infected cells was blocked by a C16 compound known to inhibit signal peptidase I. These findings have provided important molecular information for further understanding the C. trachomatis pathogenic mechanisms.     

人肺组织体外感染模型的建立及 NTHi 诱导炎症反应的机制研究

目的: 研究不可分型流感嗜血杆菌(NTHi)诱导肺组织炎症反应的关键信号通路。方法: 肺组织与NTHi(10¹⁰ CFU/L)共孵育4 h和24 h。Western blotting检测肺组织的磷酸化p38丝裂原活化蛋白激酶(p38 MAPK),电泳迁移率法检测核因子κB(NF-κB)核转位,实时定量RT-PCR检测Toll样受体(TLR)2 mRNA, 酶联免疫吸附试验检测上清的白细胞介素(IL)-8水平。另外,肺组织预先与抗TLR2单抗(anti-TLR2: 5 mg/L)、p38 MAPK抑制剂(SB203580: 20 μmol/L)或NF-κB抑制剂(PDTC: 25 μmol/L)孵育2 h,再加入NTHi(10¹⁰ CFU/L)刺激24 h,收集组织上清,测定IL-8。结果: 肺组织感染NTHi 4 h后,肺组织TLR2-p38 MAPK-NF-κB信号通路迅速被激活。感染24 h后,肺组织IL-8表达较未感染组显著增加 (P<0.05)。抗TLR2单抗、特异性p38 MAPK和NF-κB分子阻断剂可以明显抑制NTHi诱导的IL-8表达。结论: NTHi通过TLR2-p38 MAPK-NF-κB信号通路诱导肺组织分泌炎症因子。人体外肺组织感染模型为研究病原体和宿主相互作用提供了新的平台。     

Generation and characterization of a large panel of murine monoclonal antibodies against vaccinia virus

Vaccinia virus (VACV), the vaccine for smallpox, induces an antibody response that is largely responsible for conferring protection. Here, we studied the antibody response to VACV by generating and characterizing B cell hybridomas from a mouse immunized with VACV. Antibodies from 66 hybridomas were found to recognize 11 VACV antigens (D8, A14, WR148, D13, H3, A56, A33, C3, B5, A10 and F13), 10 of which were previously recognized as major antigens in smallpox vaccine by a microarray of VACV proteins produced with a prokaryotic expression system. VACV C3 protein, which was not detected as a target of antibody response by the proteome array, was recognized by two hybridomas, suggesting that selection of hybridomas based on immune recognition of infected cells has the advantage of detecting additional antibody response to native VACV antigens. In addition, these monoclonal antibodies are valuable reagents for studying poxvirus biology and protective mechanism of smallpox vaccine.     

A Chlamydia trachomatis OmcB C-terminal fragment is released into the host cell cytoplasm and is immunogenic in humans

The Chlamydia trachomatis outer membrane complex protein B (OmcB) is an antigen with diagnostic and vaccine relevance. To further characterize OmcB, we generated antibodies against OmcB C-terminal (OmcBc) and N-terminal (OmcBn) fragments. Surprisingly, the anti-OmcBc antibody detected dominant signals in the host cell cytosol, while the anti-OmcBn antibody exclusively labeled intrainclusion signals in C. trachomatis-infected cells permeabilized with saponin. Western blot analyses revealed that OmcB was partially processed into OmcBc and OmcBn fragments. The processed OmcBc was released into host cell cytosol, while the OmcBn and remaining full-length OmcB were retained within the chlamydial inclusions. The organism-associated OmcB epitopes became detectable only after the C. trachomatis-infected cells were permeabilized with strong detergents such as SDS. However, the harsh permeabilization conditions also led to the leakage of the already secreted OmcBc and chlamydia-secreted protease (CPAF) out of the host cells. The OmcBc processing and release occurred in all biovars of C. trachomatis. Moreover, the released OmcBc but not the retained OmcBn was highly immunogenic in C. trachomatis-infected women, which is consistent with the concept that exposure of chlamydial proteins to host cell cytosol is accompanied by increased immunogenicity. These observations have provided important information for further exploring/optimizing OmcB as a target for the development of diagnosis methods and vaccines.     

Tumor necrosis factor alpha production from CD8+ T cells mediates oviduct pathological sequelae following primary genital Chlamydia muridarum infection

The immunopathogenesis of Chlamydia trachomatis-induced oviduct pathological sequelae is not well understood. Mice genetically deficient in perforin (perforin(-/-) mice) or tumor necrosis factor alpha (TNF-α) production (TNF-α(-/-) mice) displayed comparable vaginal chlamydial clearance rates but significantly reduced oviduct pathology (hydrosalpinx) compared to that of wild-type mice. Since both perforin and TNF-α are effector mechanisms of CD8(+) T cells, we evaluated the role of CD8(+) T cells during genital Chlamydia muridarum infection and oviduct sequelae. Following vaginal chlamydial challenge, (i) mice deficient in TAP I (and therefore the major histocompatibility complex [MHC] I pathway and CD8(+) T cells), (ii) wild-type mice depleted of CD8(+) T cells, and (iii) mice genetically deficient in CD8 (CD8(-/-) mice) all displayed similar levels of vaginal chlamydial clearance but significantly reduced hydrosalpinx, compared to those of wild-type C57BL/6 mice, suggesting a role for CD8(+) T cells in chlamydial pathogenesis. Repletion of CD8(-/-) mice with wild-type or perforin(-/-), but not TNF-α(-/-), CD8(+) T cells at the time of challenge restored hydrosalpinx to levels observed in wild-type C57BL/6 mice, suggesting that TNF-α production from CD8(+) T cells is important for pathogenesis. Additionally, repletion of TNF-α(-/-) mice with TNF-α(+/+) CD8(+) T cells significantly enhanced the incidence of hydrosalpinx and oviduct dilatation compared to those of TNF-α(-/-) mice but not to the levels found in wild-type mice, suggesting that TNF-α production from CD8(+) T cells and non-CD8(+) cells cooperates to induce optimal oviduct pathology following genital chlamydial infection. These results provide compelling new evidence supporting the contribution of CD8(+) T cells and TNF-α production to Chlamydia-induced reproductive tract sequelae.     

First description of neurogenic sinus bradycardia in idiopathic hemifacial spasm

BACKGROUND: Idiopathic HFS accompanied by NSB is a rare clinical phenomenon and has not been reported before. Here we describe this phenomenon and discuss its mechanism and treatment. METHODS: Eighteen patients with idiopathic HFS with NSB (HR < or =55 BPM) received MVD operations. Their sinus bradycardia was proved to be neurogenic by a series of examinations. During MVD, all 18 patients were found to have their REZ of facial and vagus nerves or VMO compressed by intracranial arteries. Decompression at REZ of facial and vagus nerves and/or VMO was enforced in MVD operations. Preoperative and postoperative HR and the therapeutic efficacy of MVD for HFS with NSB were recorded. RESULTS: Fourteen cases (77.78%) were right-sided HFS. The symptom of facial spasm disappeared in 16 cases and was relieved in 1 case a year after MVD. The mean HR before MVD was 52 +/- 2.81 BPM. The mean HRs 1 week and 1 year after MVD were 63.39 +/- 5.26 and 63.17 +/- 6.46 BPM, respectively, both of which were significantly higher (P < .01) than the preoperative HR. CONCLUSIONS: Most NSBs occurred in right-sided HFS. Decompression at REZ of facial and vagus nerves and/or VMO simultaneously was an effective treatment of HFS and NSB in HFS accompanied by NSB. Severe artery compression at vagus or VMO might be the cause of NSB in HFS.