应用微弧氧化-水热处理法在纯钛表面制备生物梯度陶瓷涂层

目的 应用微弧氧化和水热处理技术在纯钛表面制备TiO2/HA梯度涂层,并对该涂层成分、形貌等理化性能进行评价.方法 纯钛试件分为三组,分别进行微弧氧化处理(M组)、微弧氧华-水热处理(M H组)和纯钛对照(C组).采用扫描电镜观察表面形貌并用X线衍射对其进行成分分析,通过划痕实验检测膜基结合力.结果 做弧氧化处理后试件表面呈现多孔状,主要为锐钛矿型TiO2;经过后续水热处理,从扫描电镜(SEM)照片可以看到试件表面析出一层白色柱形结晶体,同时X射线衍时仪(XRD)潜线出现了羟基磷灰石的衍射峰.结论 微弧氧化及水热处理能够增强纯钛种植体的生物相容性.     

纯镁微弧氧化-NaOH-Zn膜层的抗菌性研究

目的:研究纯镁微弧氧化-NaOH-Zn膜层的抗菌性.方法:超声微弧氧化组(MAO)设为A组,化学镀锌10min的MAO纯镁(MAO-Zn)设为B组,碱处理后化学镀锌10min的MAO纯镁(MAO-NaOH-Zn)设为C组.进行抗菌试验,对比实验结果.结果:C组24h黄色葡萄球菌和大肠杆菌菌落数明显低于B组、A组,C组抗...     

钛表面载银抗菌功能膜的抑菌性研究

目的 通过对钛片进行表面处理制备出载银抗菌功能膜,研究处理前后钛片对种植体周围炎易感细菌的抑菌性能.方法 利用微弧氧化法在钛表面制备陶瓷层,运用光催化沉积将银离子沉积于陶瓷层表面,制得含银离子的杭菌功能膜;采用扫描电镜观察钛片处理前后表面形貌及抗细菌黏附性能;通过计算抑菌率研究处理前后钛片对牙龈卟啉单胞菌及金黄色葡萄球...     

承载抗生素类药物植入剂的抑菌活性研究

目的 观察载有左氧氟沙星和利福平的聚乳酸植入剂对金黄色葡萄球菌和大肠杆菌的体外抑菌活性.方法 通过将载药植入剂(实验组)和空白植入体(对照组)置于分别含金黄色葡萄球菌和大肠杆菌的固体培养基平皿中,观察1、13、40d抑菌圈变化,每隔72小时测量1次抑菌圈直径,分析其变化.结果 实验组载药植入剂对两种菌的抑菌活性均可持续到40d以上,但随着时间的增加,抑菌活性逐渐减弱.载药植入剂对大肠杆菌的抑菌作用出现双峰现象而对金黄色葡萄球菌无此现象.结论 承载组合抗生素药物的植入剂在体外抑菌活性显著,抑菌时间长,具有潜在的临床应用价值.     

一种基于GO-金属离子复合物抑菌性的PLGA多功能超声造影剂

基于氧化石墨烯(GO)与金属离子(Ag⁺、Zn²⁺、Cu²⁺、Co²⁺)的抑菌性,制备了一种兼具抗炎与超声显影作用的GO-金属离子复合物聚乳酸-羟基乙酸共聚物(PLGA)多功能超声造影微泡。GO与4种金属盐(硝酸银、氯化锌、五水合硫酸铜、六水合氯化钴)中的金属离子,通过静电自组装形成GO-金属离子复合物(GO-Ag⁺、GO-Zn²⁺、GO-Cu²⁺,GO-Co²⁺),采用复乳化-溶剂挥发法分别制备负载上述复合物的PLGA微泡,所得的PLGA微泡的粒径为508.7~633.0nm,ζ电位为(-32.7±10.0)-(-44.4±10.0)mV。复合物微泡对正常的小鼠成纤维细胞(3T3)没有明显毒性,对大肠埃希菌与金黄色葡萄球菌均有显著抑菌性能,且对家兔膀胱有较好的显影效果。     

头孢拉定无菌检查消除抑菌性的研究

目的:通过一系列试验,建立头孢拉定检查法。方法:用不同试验菌,同时采用青霉素酶进行试验。结果:头孢拉定无菌检查时,对金黄色葡萄球菌有较强的抑活性。结论:头孢拉定无菌检查需加青霉素酶来消除抑菌性,以保证无菌检查的准确性。     

无患子皂苷的提取及抑菌性研究

目的 优化无患子皂苷的提取工艺,并测定提取物的抑菌活性.方法 本研究起止时间为2018年3月至2019年3月.以乙醇为提取剂,采用超声波辅助法,通过正交试验对无患子皂苷的提取工艺进行研究;采用滤纸片扩散法测定提取物对细菌和真菌的抑制效果.结果 无患子皂苷的最佳提取工艺是以70％的乙醇为提取溶剂,料液比为1:5,超声提取...     

镁合金涂覆不同浓度硅-羟基磷酸钙后的体外生物相容性评价

目的利用大鼠成骨细胞在体外评价使用硅-羟基磷酸钙涂覆的镁合金的毒性反应。方法利用大鼠颅骨培养第三代成骨细胞,之后与二种覆有不同硅-羟基磷酸钙涂层的镁合金进行共培养,之后通过细胞活力检测、碱性磷酸酶检测、扫描电镜观察评估细胞生长情况。结果细胞活力检测和碱性磷酸酶检测表明,第一种硅(12%)-羟基磷酸钙涂覆的镁合金利于成骨细胞的生长;扫描电镜下可见成骨细胞在第一种硅(12%)-羟基磷酸钙涂层表面的镁合金生长均匀,增殖明显。结论硅含量在12%的硅-羟基磷酸钙涂层利于成骨细胞的体外黏附和生长。     

枇杷叶多糖的提取及抑菌活性研究

目的:优化枇杷叶中多糖提取的工艺条件,并考察其抑菌活性。方法:以干燥的枇杷叶粉末为原料,采用水提法对枇杷叶中的多糖进行提取,通过正交实验筛选出最佳工艺参数;考察枇杷叶多糖对金黄色葡萄球菌,枯草芽孢杆菌和大肠杆菌的抑菌效果。结果:通过实验表明,枇杷叶多糖最佳提取温度为70℃,提取时间为2h,料液比为1∶40,此时,枇杷叶多糖提取量为16.224mg/g。枇杷叶多糖的抑菌实验结果显示,枇杷叶多糖对大肠杆菌抑制作用最强,对金黄色葡萄球菌和枯草芽孢杆菌抑制作用较弱。结论:枇杷叶中多糖成分丰富,有一定抑菌作用,该研究为枇杷叶活性成分筛选及进一步的扩展应用提供了理论依据。     

镁及镁合金植入体在骨科临床中的应用分析

目的：探讨并分析镁及镁合金植入体在骨科临床中的应用。方法回顾性分析关于镁及镁合金在医学领域及骨科临床中的应用情况,并对结果进行参考和总结。结果镁合金具有良好的生物相容性及可降解性和生物安全性等优点,并且其资源丰富,可在生理电解质环境中通过腐蚀而发生降解的特性,展示了其在骨科领域巨大的潜在应用前景,在骨科临床中的应用效果显著。结论镁及镁合金是未来生物医用植入材料重要的发展方向之一,值得临床推广应用。     

Antibacterial property and clinical effect of gatifloxacin,a novel quinolone antibacterial agent

Gatifloxacin, a novel 8-methoxyquinolone, was approved in April 2002 and launched in June 2002. Gatifloxacin shows a broad spectrum of antibacterial activity against Gram-negative, Gram-positive, anaerobic, and atypical pathogens. The activity is higher than those of other quinolones against RTI pathogens of S. pneumoniae including the penicillin-resistant strains, H. influenzae, Mycoplasma, and Chlamydia. This drug strongly inhibits the type II topoisomerase, DNA gyrase, and topoisomerase IV of S. pneumoniae and S. aureus to nearly the same extent, leading to the potent activity and low resistance. After an oral administration in humans, gatifloxacin is well absorbed and distributed, and the majority is excreted in the urine as the unchanged form. Its serum half-life is 7-8 h. The clinical effectiveness was observed for various infectious diseases including RTI and UTI. The bacterial eradication rate is 94.1% for Gram-positives, 90.7% for Gram-negatives, and 97.7% for anaerobes. In particular, gatifloxacin showed a high eradication rate of 98.7% for S. pneumoniae. The total cure rate and eradication rate of gatifloxacin in clinical studies are 91.1% and 93.3%, respectively, indicating that the potent activity and good PK profile account for its clinical efficacy.     

Improved antibacterial and antibiofilm activity of magnesium fluoride nanoparticles obtained by water-based ultrasound chemistry

Antibiotic resistance has prompted the search for new agents that can inhibit bacterial growth. We recently reported on the antimicrobial and antibiofilm activities of nanosized magnesium fluoride (MgF₂) nanoparticles (NPs) synthesized in ionic liquid using microwave chemistry. In this article, we describe a novel water-based synthesis of MgF₂ NPs using sonochemistry. The sonochemical irradiation of an aqueous solution of [Mg(OAc)₂?(H₂O)₄] containing acidic HF as the fluorine ion source afforded crystalline well-shaped spherical MgF₂ NPs that showed much improved antibacterial properties against two common bacterial pathogens (Escherichia coli and Staphylococcus aureus). We were also able to demonstrate that the antimicrobial activity was dependent on the size of the NPs. In addition, using the described sonochemical process, we coated glass surfaces and demonstrated inhibition of bacterial colonization for 7 days. Finally, the antimicrobial activity of MgF₂ NPs against established biofilms was also examined. Taken together our results highlight the potential to further develop the concept of utilizing these metal fluoride NPs as novel antimicrobial and antibiofilm agents.From the Clinical EditorIn this article, the authors describe a novel aqueous synthesis of magnesium fluoride NPs using sonochemistry. These nanoparticles have improved antibacterial and antibiofilm activity compared to their counterparts with traditional synthesis methods.     

Chitosan derivative nanocarrier: Safety evaluation,antibacterial property and ascorbyl palmitate encapsulation

A chitosan derivative, methyl ether-terminated poly(ethylene oxide)-4-methoxycinnamolyphthaloylchitosan (PCPLC) was prepared, characterized and self-assembled into nanoparticles. Encapsulation of ascorbyl palmitate (AP) into PCPLC gave 689 ± 0.98 nm particles with encapsulation efficiency of 84% at 56% drug loading. The encapsulated AP showed significant improved stability as examined by ¹H NMR spectroscopy. The obtained particles displayed no short-term cytotoxicity against the human skin melanoma A-375 cell line using the MTT assay and no short-term skin irritation on human volunteers using a single topical application as patch and photopatch tests. In addition, aqueous suspension of PCPLC nanoparticles successfully inhibited the growth of Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923.     

可降解镁基合金骨折固定及骨修复材料的研究进展

可降解镁基合金材料具有良好的力学性能、突出的生物相容性和成骨诱导性。其作为有临床应用前景的骨折固定及骨修复替代材料近年来备受关注。本文就可降解医用镁合金材料在骨折固定及骨修复领域的研究进行总结,分别从镁合金骨折固定及骨修复材料的优势、发展历史、研究及应用现状、存在的问题与挑战等几个方面进行了综述。     

兔源益生菌Tu-569菌株鉴定与其胞外产抑菌物性质分析

目的对兔源益生菌Tu-569菌株进行菌落形态和菌体形态观察、生理生化特性测定及16S rDNA序列系统发育分析以确定其种属。方法以大肠埃希菌为指示菌,通过琼脂打孔扩散法分析Tu-569菌株胞外产抑菌物性质,初步评价该抗菌物活性。结果 Tu-569菌株为Bacillus velezensis;Tu-569菌株胞外产抑菌物为分子量3.5～8.0kD的多肽,可被饱和度60%的硫酸铵盐析;该抗菌肽热稳定性较好,但可被蛋白酶降解;采用正丁醇萃取该抗菌肽不会降低其活性;其活性可被Mn2+离子增强,但在强酸(pH 3)强碱(pH11)环境中会大幅度降低;当存在表面活性剂和β-巯基乙醇时,抗菌肽抑菌活性完全丧失。每1mg粗蛋白中含有的抗菌肽抑制大肠埃希菌的能力相当于2μg硫酸庆大霉素、10μg硫酸链霉素或50μg土霉素。结论该抗菌肽性质稳定,具有较高的抗菌活性,在畜牧业、养殖业、食品等领域中有一定的应用价值。     

重组人骨形成蛋白-2胶原珊瑚复合人工骨异位诱导成骨的实验研究

目的 本研究采用珊瑚作为载体,胶原作为缓释系统,制备出重组入骨形成蛋白2(rhBMP2)/胶原/珊瑚复合人工骨,并评价其骨诱导活性。方法 rhBMP2、胶原和珊瑚以一定的方式复合后,植入小鼠股部肌袋内,以单纯珊瑚植入作对照,术后不同时间取材,通过组织学方法检测骨诱导活性。结果 复合人工骨植入小鼠肌袋,1周诱导软骨形成,2周形成编织骨,4周形成含骨髓的板层骨,同时珊瑚被部分降解吸收。结论 胶原、珊瑚是rhBMP2较理想的载体,有缓释BMP的作用,该复合骨具有良好的异位诱骨活性,是一种比较理想的新型生物性植骨材料。     

2,4-二氯-6-硝基酚铵诱发小鼠肺肿瘤研究

用２,４－二氯－６－硝基酚铵（ＤＣＮＰＡ）进行小鼠肺肿瘤诱发试验。分别作ＤＣＮＰＡ１次腹腔注射染毒,ＤＣＮＰＡ１次染毒＋ＢＨＴ促进,和ＤＣＮＰＡ１次染毒＋ＢＨＴ促进＋ＤＣＮＰＡ演进３个试验。结果提示ＤＣＮＰＡ为完全致癌物,因为ＤＣＮＰＡ不需ＢＨＴ促进即能诱发肺腺瘤,试验结果也提示ＤＣＮＰＡ有一定的演进作用。     

Preparation,characterisation and in vitro antibacterial property of ciprofloxacin-loaded nanostructured lipid carrier for treatment of Bacillus subtilis infection

Context: In this study, controlled ciprofloxacin (CIPRO) nanostrustructured lipid carriers of Precirol^® ATO 5/Transcutol^® HP (batch A) and tallow fat/Transcutol^® HP (batch B) was carreid out. Objective: The aim was to improve solubility and bioavailability of CIPRO.

Objective: Study of controlled ciprofloxacin (CIPRO) nanostructured lipid carriers of Precirol^® ATO 5/Transcutol^® HP (batch A) and tallow fat/Transcutol^® HP (batch B).

Methods: CIPRO concentrations C_1–5 (0.0, 0.2, 0.5, 0.8, and 1.0% w/w) as AC_1–5 and BC_1–5 were prepared by hot homogenisation and characterised by zetasizer, differential scanning calorimetry, Fourier transform infra-red spectroscopy, in vitro drug release and growth inhibitory zone diameter (IZD) on agar-seeded Bacillus subtilis.

Results: AC₅ achieved polydispersed particles of ～605?nm, 92% encapsulation efficiency (EE) and –28?mV similar to BC₅ (～789?nm, 91% EE, and –31?mV). Crystallinity indices (AC₅ and BC₅) were low at 3 and 5%, respectively. CIPRO release in AC₅ was ～98% in SGF (pH 1.2) and BC₅ similarly ～98% in SIF (pH 6.8).

Conclusions: AC₅ had superior growth inhibition of B. subtilis at lower concentration (1.2 µg/mL) than BC₅ and CIPRO controls; hence could serve as possible sustained delivery system of CIPRO.