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目的:通过长期随访27例外科治疗脊柱结核病例,探讨外科方法对于脊柱结核的治疗效果。方法:回顾性分析本单位近10年来收治的采用病灶清除植骨内固定术治疗的27例脊柱结核病例,通过分析平均44个月的随访结果,评价外科手术和药物干预的治疗效果。结果:本组所有患者早期随访结果显示:伤口一期愈合,内固定稳定,脊髓压迫症状缓解或消失。长期随访结果显示:能够贯彻全程化疗方案的病例,植骨完全融合,脊髓症状无反复,结核病灶无复发;未能完成化疗方案的4例患者在切口部位出现窦道,并在植骨床周围形成死骨,感染复发。4例复发患者经全身使用抗结核药物和二次手术翻修,在完成12月术后化疗后治愈。结论:对于脊柱结核必需坚持外科手术与术后全程化疗并重的的治疗方法。 相似文献
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van der Woude AD Sarkar D Bhatt A Sparrius M Raadsen SA Boon L Geurtsen J van der Sar AM Luirink J Houben EN Besra GS Bitter W 《The Journal of biological chemistry》2012,287(24):20417-20429
The mycobacterial cell envelope is characterized by the presence of a highly impermeable second membrane, which is composed of mycolic acids intercalated with different unusual free lipids, such as lipooligosaccharides (LOS). Transport across this cell envelope requires a dedicated secretion system for extracellular proteins, such as PE_PGRS proteins, which are specific mycobacterial proteins with polymorphic GC-rich sequence (PGRS). In this study, we set out to identify novel components involved in the secretion of PE_PGRS proteins by screening Mycobacterium marinum transposon mutants for secretion defects. Interestingly, most mutants were not affected in secretion but in the release of PE_PGRS proteins from the cell surface. These mutants had insertions in a gene cluster associated with LOS biosynthesis. Lipid analysis of these mutants revealed a role at different stages of LOS biosynthesis for 10 novel genes. Furthermore, we show that regulatory protein WhiB4 is involved in LOS biosynthesis. The absence of the most extended LOS molecule, i.e. LOS-IV, and a concomitant accumulation of LOS-III was already sufficient to reduce the release of PE_PGRS proteins from the mycobacterial cell surface. A similar effect was observed for major surface protein EspE. These results show that the attachment of surface proteins is strongly influenced by the glycolipid composition of the mycobacterial cell envelope. Finally, we tested the virulence of a LOS-IV-deficient mutant in our zebrafish embryo infection model. This mutant showed a marked increase in virulence as compared with the wild-type strain, suggesting that LOS-IV plays a role in the modulation of mycobacterial virulence. 相似文献
995.
The members of the antigen 85 protein family (Ag85), consisting of members Ag85A, Ag85B, and Ag85C, are the predominantly secreted proteins of mycobacteria and possess the ability to specifically interact with fibronectin (Fn). Because Fn-binding proteins are likely to be important virulence factors of Mycobacterium spp., Ag85 may contribute to the adherence, invasion, and dissemination of organisms in host tissue. In this study, we reported the Fn binding affinity of Ag85A, Ag85B, and Ag85C from Mycobacterium avium subsp. paratuberculosis (MAP) (K(D) values were determined from 33.6 to 68.4 nm) and mapped the Ag85-binding motifs of Fn. Fn14, a type III module located on the heparin-binding domain II (Hep-2) of Fn, was discovered to interact with Ag85 from MAP. The peptide inhibition assay subsequently demonstrated that a peptide consisting of residues 17-26 from Fn14 ((17)SLLVSWQPPR(26), termed P17-26) could interfere with Ag85B binding to Fn (73.3% reduction). In addition, single alanine substitutions along the sequence of P17-26 revealed that the key residues involved in Ag85-Fn binding likely contribute through hydrophobic and charge interactions. Moreover, binding of Ag85 on Fn siRNA-transfected Caco2 cells was dramatically reduced (44.6%), implying the physiological significance of the Ag85-Fn interaction between mycobacteria and host cells during infection. Our results indicate that Ag85 binds to Fn at a novel motif and plays a critical role in mycobacteria adherence to host cells by initiating infection. Ag85 might serve as an important colonization factor potentially contributing to mycobacterial virulence. 相似文献
996.
Ved Prakash Dwivedi Debapriya Bhattacharya Samit Chatterjee Durbaka Vijay Raghva Prasad Debprasad Chattopadhyay Luc Van Kaer William R. Bishai Gobardhan Das 《The Journal of biological chemistry》2012,287(40):33656-33663
Mycobacterium tuberculosis, the causative agent of tuberculosis (TB), resides and replicates within phagocytes and persists in susceptible hosts by modulating protective innate immune responses. Furthermore, M. tuberculosis promotes T helper 2 (Th2) immune responses by altering the balance of T cell polarizing cytokines in infected cells. However, cytokines that regulate Th2 cell differentiation during TB infection remain unknown. Here we show that IL-1β, produced by phagocytes infected by virulent M. tuberculosis strain H37Rv, directs Th2 cell differentiation. In sharp contrast, the vaccine strain bacille Calmette-Guérin as well as RD-1 and ESAT-6 mutants of H37Rv failed to induce IL-1β and promote Th2 cell differentiation. Furthermore, ESAT-6 induced IL-1β production in dendritic cells (DCs), and CD4+ T cells co-cultured with infected DCs differentiated into Th2 cells. Taken together, our findings indicate that IL-1β induced by RD-1/ESAT-6 plays an important role in the differentiation of Th2 cells, which in turn facilitates progression of TB by inhibiting host protective Th1 responses. 相似文献
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