NiTi根管器械表面耐磨镀层的制备和性能研究

目的：研究镍钛合金表面耐磨镀层的制备工艺和性能,提高镍钛根管器械的表面硬度和耐磨性。方法：采用直流电镀法在NiTi合金表面制备了Ni—W合金镀层,通过能谱分析和X射线衍射技术（XRD）研究电镀工艺对Ni—W耐磨镀层成分和结构的影响。采用销一盘式摩擦试验机对耐磨Ni—W合金镀层的耐磨性进行测试,通过磨损失重和磨痕形貌观察评价和分析了Ni—W合金镀层的耐磨性和耐磨机理。结果：在NiTi合金表面所制备的Ni—W合金耐磨镀层的W含量在15．2．20．2wt％范围内,且镀层致密,无微观裂纹。Ni—W合金镀层的结构是W在Ni中的固溶体。与Ni—Ti合金基体相比,镀有Ni—W合金镀层的Ni—B合金试样的磨损失重大幅度降低,耐磨性显著提高;Ni—W合金镀层的硬度和耐磨性随镀层中W含量的增加而增大。结论：直流电镀技术对镍钛合金根管器械进行表面改性可显著提高其耐磨忡．     

Favorable outcome in a renal transplant recipient with donor-derived infection due to multidrug-resistant Pseudomonas aeruginosa

Most cases of donor-derived infection due to Pseudomonas aeruginosa reported in the literature are associated with vascular dehiscence, all of which resulted either in death or graft failure requiring graft removal. We report the successful treatment of donor-derived infection due to multidrug-resistant P. aeruginosa in a 64-year-old male who presented with bacteremia and peritransplant renal fluid collection after undergoing deceased-donor renal transplantation. As a result of the report of positive donor cultures by the host Organ Procurement Organization, the infection was promptly identified by blood cultures drawn before appearance of symptoms. Surveillance blood cultures in recipients are not usually recommended. However, they should be done if donor cultures turn positive. Therefore, it is crucial to perform cultures in donors and to closely follow them up for early identification and prompt treatment of donor-transmitted infections due to organisms like P. aeruginosa that can be graft and/or life threatening.     

齿科种植体钛的耐磨损性质探讨

目的：探讨齿科种植体材料钛的耐磨损性及其对种植体牙周维护的远期影响。方法：应用Martens划痕实验与超声洁牙机磨损实验对钛板进行耐磨损性检测。结果：Martens划痕实验与超声洁牙机磨损实验结果显示其在不同的荷重下均会对钛板造成不同程度的划痕及磨损。讨论：采用常规牙周维护方法可能会对钛种植体造成磨损,可能加重种植体表面上牙石及菌斑的沉积与结合,对钛种植体的远期预后产生不良影响。     

Breast cancer resistance protein (Bcrp) and the testis—an unexpected turn of events

Breast cancer resistance protein (Bcrp) is an ATP-dependent efflux drug transporter. It has a diverse spectrum of hydrophilic and hydrophobic substrates ranging from anticancer, antiviral and antihypertensive drugs, to organic anions, antibiotics, phytoestrogens (e.g., genistein, daidzein, coumestrol), xenoestrogens and steroids (e.g., dehydroepiandrosterone sulfate). Bcrp is an integral membrane protein in cancer and normal cells within multiple organs (e.g., brain, placenta, intestine and testis) that maintains cellular homeostasis by extruding drugs and harmful substances from the inside of cells. In the brain, Bcrp is a major component of the blood–brain barrier located on endothelial cells near tight junctions (TJs). However, Bcrp is absent at the Sertoli cell blood–testis barrier (BTB); instead, it is localized almost exclusively to the endothelial TJ in microvessels in the interstitium and the peritubular myoid cells in the tunica propria. Recent studies have shown that Bcrp is also expressed stage specifically and spatiotemporally by Sertoli and germ cells in the seminiferous epithelium of rat testes, limited only to a testis-specific cell adhesion ultrastructure known as the apical ectoplasmic specialisation (ES) in stage VI–early VIII tubules. These findings suggest that Bcrp is equipped by late spermatids and Sertoli cells to protect late-stage spermatids completing spermiogenesis. Furthermore, Bcrp was found to be associated with F (filamentous)-actin and several actin regulatory proteins at the apical ES and might be involved in the organisation of actin filaments at the apical ES in stage VII–VIII tubules. These findings will be carefully evaluated in this brief review.     

Silver oxide‐containing hydroxyapatite coating has in vivo antibacterial activity in the rat tibia

Bacterial infection is a serious postoperative complication of joint replacement. To prevent infections related to implantation, we have developed a novel antibacterial coating with Ag‐containing hydroxyapatite (Ag‐HA). In the present study, we examined the antibacterial activity of Ag‐HA implant coatings in the medullary cavity of rat tibiae. Forty 10‐week‐old rats received implantation of Ag‐HA‐ or HA‐coated titanium rods, then were inoculated with ～1.0 × 10² colony‐forming units of methicillin‐resistant Staphylococcus aureus. Bacterial counts were calculated for rats euthanized at 24, 48, and 72 h postoperatively. Serum levels of Ag (in the Ag‐HA group only) were calculated for rats euthanized at 24, 48, 72 h and 4 weeks. Radiographic evaluations of bone infection were also performed at 4 weeks. Tibiae from both groups showing infection were evaluated histologically. Significant differences in bacterial counts were seen at 24, 48, and 72 h. Mean concentrations of Ag in serum peaked about 48 h after implantation, then gradually decreased. Mean radiographic scores for infection were significantly lower with Ag‐HA implants than with HA implants. Histological examination showed better results for abscesses, bone resorption, and destruction of cortical bone around Ag‐HA‐coated implants. These results indicate that Ag‐HA coatings may help prevent surgical‐site infections associated with joint replacement. © 2013 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 31:1195–1200, 2013     

Thalidomide for Treatment of Bleeding Angiodysplasias during Hemodialysis

Renal transplant patients are more prone to tuberculosis infection due to the underlying intense immunosuppression, with an incidence 20–74 times higher than that in the general population. It is associated with graft dysfunction and increased mortality rates. It can be frequently pulmonary but extra-pulmonary involvement is not rare, and in the latter case, it may be misinterpreted as genital malignancies. In this case report, we discuss a renal transplant patient with pelvic pain and fever, who was later diagnosed as having abdominopelvic tuberculosis.