活性屏等离子表面改性技术制备纳米银涂层不锈钢的体外抗菌性能

背景:既往利用活性屏等离子技术制备的银涂层大都不涉及纳米领域,形成的银涂层为“薄膜样”,被覆基质表层且表面银颗粒分布不均,其长效抗菌能力受到挑战。目的:采用活性屏等离子体表面改性(ASPSM)技术制备可“埋入”不锈钢(SS)基质内部的纳米银涂层,观察其抗菌能力。方法:以不锈钢为基体,采用ASPSM技术制备纳米银涂层,其中通过调整轰击时间(1,2,4 h)制备3组涂层样品,分别记为1 h-Ag-ASPSM@SS、2 h-Ag-ASPSM@SS和4 h-Ag-ASPSM@SS,通过抑菌环实验、革兰染色分析3组涂层的抗菌能力。以不锈钢为基体,制备庆大霉素联合万古霉素抗生素涂层样品,记为ACNs。将不锈钢、2 h-Ag-ASPSM@SS、ACNs分别插入金黄色葡萄球菌或铜绿假单胞菌悬液中,采用涂布平板法分析样品长效(84 d)抗菌能力。将骨髓间充质干细胞分别与不锈钢、2 h-Ag-ASPSM@SS、ACNs共培养,进行CCK-8、活死染色与细胞上清乳酸脱氢酶活性检测。取连续暴露于金黄色葡萄球菌悬液12周后的不锈钢、2 h-Ag-ASPSM@SS、ACNs,采用滚平板法评估材料表面残留活菌量,采用万古霉素药敏纸片法评估材料表面残留活菌耐药性。结果与结论:①随着轰击时间的延长,样品表面纳米银的直径与含量逐渐增加,其中2 h-Ag-ASPSM@SS在形成了均匀球形纳米颗粒的情况下表面银含量较高。②抑菌环实验、革兰染色显示,相较于1 h-Ag-ASPSM@SS、4 h-Ag-ASPSM@SS,2 h-Ag-ASPSM@SS对金黄色葡萄球菌与铜绿假单胞菌有更好的抑制效果。与两种细菌共培养42,84 d后,2 h-Ag-ASPSM@SS组洗脱液涂布平板上的活菌数量显著少于不锈钢组、ACNs组;与金黄色葡萄球菌共培养84 d后、与铜绿假单胞菌共培养42 d后,ACNs组洗脱液涂布平板上的活菌数量多于不锈钢组。③CCK-8、活死染色与细胞上清乳酸脱氢酶活性检测显示,2 h-Ag-ASPSM@SS无明显的细胞毒性,ACNs具有明显的细胞毒性。④与金黄色葡萄球菌共培养12周后,2 h-Ag-ASPSM@SS组表面残留活菌量少于不锈钢组,ACNs组表面残留活菌量多于不锈钢组;与不锈钢组比较,ACNs组表面残留活菌株对万古霉素的敏感性显著下降(P<0.001),2 h-Ag-ASPSM@SS组表面残留活菌株对万古霉素的敏感性无明显变化(P>0.05)。⑤结果表明,ASPSM技术制备的纳米银涂层提高了不锈钢表面纳米银含量的沉积效率,并且具有持久的抗菌特性、良好的细胞相容性。     

慢性乙型肝炎患者血清铁调素和铁代谢指标及体外HBV转染Huh7细胞铁调素水平变化*

目的 探讨慢性乙型肝炎(CHB)患者血清铁调素(Hepc)和铁代谢指标的变化,并在体外观察HBV转染肿瘤细胞Hepc表达的变化。方法 在71例CHB患者和24例健康体检者,采用ELISA法检测血清Hepc水平,使用全自动蛋白分析仪检测血清铁(SI)、铁蛋白(Ferr)和转铁蛋白(Tf)水平。使用电化学发光全自动免疫分析仪检测血清IL-6水平。构建HBV感染Huh7细胞模型,分别采用RT-qPCR和Western blot法检测细胞Hepc表达情况。结果 与健康人比较,CHB组血清SI、Ferr、IL-6、丙氨酸氨基转移酶 (ALT)、天门冬氨酸氨基转移酶(AST)、血清总胆红素 (TBIL)水平均显著升高,Hepc、Tf和可溶性转铁蛋白受体(sTfR)、白蛋白(ALB)显著降低(P<0.05);转染细胞24 h,Hepc mRNA相对水平为(5.21±0.43),空白对照细胞的(0.73±0.14)显著升高(P<0.05),在转染48 h,细胞Hepc mRNA水平为(8.45±0.61),较空白对照的(1.16±0.17)显著升高(P<0.05);在质粒转染48 h后,细胞Hepc蛋白相对表达量为(0.78±0.08),较空白对照的(0.41±0.02)显著升高(P<0.05)。结论 检测铁调素及其铁代谢相关指标有助于评估慢性乙型肝炎病情进展,适当予以铁调素或者其相应内源性激活剂针对性地治疗铁超载CHB患者,是否可应用于临床,值得期待。     

微创双切口解剖重建喙锁韧带手术治疗老年肩锁关节完全脱位

目的探讨微创双切口双Endobutton钢板解剖重建喙锁韧带治疗老年肩锁关节完全脱位的临床疗效。方法回顾性分析自2009-12—2016-12采用微创双切口双Endobutton钢板解剖重建喙锁韧带治疗21例老年RockwoodⅢ、Ⅴ型肩锁关节脱位。结果 21例均获得随访,随访时间平均50(12~79)个月。术后所有患者肩关节上举及负重运动时无明显疼痛,其中19例肩关节外展活动度良好,可上举过头顶且与健侧无明显差异。末次随访时UCLA评分平均26.4(17~30)分,疼痛VAS评分平均1.6(0~4)分,肩关节功能Constant评分平均92.5(64~100)分;术后1年按Karlsson标准评定疗效:优18例,良3例。结论采用微创双切口双Endobutton钢板解剖重建喙锁韧带治疗老年RockwoodⅢ、Ⅴ型肩锁关节脱位可取得良好的疗效,手术操作简单、软组织损伤小、术后患者康复时间明显缩短,无需二次手术取出内固定。     

治疗耐药金黄色葡萄球菌感染的新策略——噬菌体裂解酶

金黄色葡萄球菌是一种重要的人畜共患病原菌,可引起人和动物的多种感染性疾病。耐药菌的出现大大增加了临床治疗难度。裂解酶是噬菌体侵染细菌后期合成的细菌细胞壁肽聚糖水解酶,不仅具有高效的裂菌活性且不易诱导细菌产生对抗生素的耐受。这些特性使其成为近年来研发新型抗菌制剂的热点。本文将重点阐述裂解酶的作用机制和抗菌活性的最新研究进展,旨在为防控耐药金黄色葡萄球菌感染提供新思路。     

姜黄素抑制大鼠创伤性骨关节炎模型中软骨细胞核因子κB P65核转位的实验研究

BACKGROUND: Mechanical, inflammatory, and biochemical factors, particularly matrix metalloproteinases and reactive oxygen lead to chondrocyte degeneration in osteoarthritis. Curcumin has been shown to be a potent antioxidant; however, its protective effects against chondrocyte degeneration in osteoarthritis remain unclear. OBJECTIVE: To investigate the potential molecular mechanisms underlying the protective effects of curcumin on articular cartilage of osteoarthritis in rats. METHODS: A total of 30 Sprague-Dawley rats were used and randomly divided into model group (positive control, n=15) and normal group (negative control, n=15). Rat models of traumatic osteoarthritis were established, and then cartilage cells were isolated from articular cartilage and cultured in vitro. Chondrocytes were treated with curcumin (curcumin group) or PDTC (an inhibitor of nuclear factor-kappa B) for 24 hours. The expression level of nuclear factor-kappa B P65 in nucleus and cytoplasm in chondrocytes were determined by western blot assay and immunofluorescence. Moreover, mRNA expressions of type II collagen, matrix metalloproteinase-1 and -13 were analyzed using RT-qPCR. RESULTS AND CONCLUSION: Nuclear factor-kappa B P65 protein was mainly expressed in nucleus, but few in cytoplasm in positive control group; the reversed results were found in the curcumin group. Nuclear translocation of nuclear factor-kappa B P65 was observed mainly in nucleus in the positive control group; however, that was observed mainly in cytoplasm in the negative control, curcumin, and PDTC groups. Matrix metalloproteinase-1 and -13 mRNA expressions were significantly decreased, while type II collagen mRNA expression was significantly increased in the curcumin group compared with the positive control group. These findings indicated that curcumin protect chondrocytes against degeneration through inhibiting the activation of nuclear factor-kappa B signaling pathway, suppressing nuclear translocation of nuclear factor-kappa B P65 and inhibiting the expressions of matrix metalloproteinase-1 and -13, which are responsible for upregulation of type II collagen expression. 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程