【作者】 吕晓东；

【导师】 蔡谞；

【作者基本信息】 中国人民解放军军医进修学院 ， 外科学， 2010， 硕士

【摘要】 目的：本研究选取1种不含抗生素进口骨水泥,实验用三氯生和硫酸庆大霉素2种粉末性状的抗菌活性物质,3种临床常见感染菌：金黄色葡萄球菌、表皮葡萄球菌、大肠杆菌。分别取不同剂量三氯生和庆大霉素与骨水泥混合搅拌,制成一定规格的抗菌活性骨水泥药片,放入3种临床常见感染菌培养皿中,比较：不同药片放入后①在细菌培养皿中,不同的时间点观察并测量抑菌环的直径大小,创建体外三氯生抗菌活性骨水泥随时问变化的药物释放规律的模型,②按照国际标准制成不同剂量的骨水泥的模件,通过生物力学压力、弯曲强度和弹性模量测试,比较两种抗菌活性骨水泥的生物力学性能。方法：实验于2009-2／2009-10在解放军总医骨科实验室和临床微生物科进行。①抗菌活性骨水泥药片样本的制备：将三氯生、庆大霉素分别称量出0.5g、1.0g、1.5g、2.0g的剂量与40g骨水泥在无菌条件下混合,各加入15mL的骨水泥附带单体,搅拌2min后,加入由高密度聚乙烯制成的模具之中塑形,制成直径6mm、厚度3mm的矮圆柱体,每一剂量各制6个。②测量生物力学性能模型的制备：A：骨水泥压缩强度测定模件：不同剂量的三氯生和硫酸庆大霉素与骨水泥混合后浇注成圆柱体(长度正好为12mm±0.1mm,直径6mm±0.1mm),在23℃环境温度中,保存骨水泥圆柱体。B：骨水泥弯曲强度、弯曲模量测定模件：模具由高密度聚乙烯制成,每只模具有一个模槽,长75mm,宽10mm,深3.3mm,共六只。③抑菌试验指标的测量：把不同剂量(0.5g、1.0g、1.5g、2.0g)混合后的三氯生骨水泥和硫酸庆大霉素骨水泥,分别各制成6个标本,放入三种实验菌中,每一个培养皿中放4个不同剂量的标本,在37℃细菌孵育箱中培养,然后观察抑菌环的大小。每24h更换新培养皿1次。分别观察24h、48h、72h、96h、1周,直至抑菌环直径小于6mm为止。④生物力学测定：A：骨水泥的压缩强度：对每个圆柱体,记录引起破裂的力或2%屈服力或上屈服点负载,哪个先出现就记录哪个,将该力除以圆柱体的原始截面,所得的商即压缩强度,以MPa为单位。计算6个圆柱体的平均压缩强度。B：骨水泥弯曲强度、弯曲模量的测定：三氯生和庆大霉素分别与骨水泥混合后,空白对照组骨水泥分别浇注到实验板条之中塑型,塑型后将所有实验板条,放到四点弯曲实验装置上,记录作为受力函数的板条中心偏离。不断增加力直至试验板条断裂。记录断裂时的力。统计学采用CHISS2004软件进行统计分析,计量资料数据用(x±s)表示,以p<0.05为差异有统计学意义,不同剂量抗菌活性剂的抗菌作用的组问比较应用方差分析。结果：1.时间依赖性的三氯生骨水泥与硫酸庆大霉素骨水泥的抗菌活性作用1.10.5～2.0g的三氯生与硫酸庆大霉素骨水泥对金黄色葡萄球菌、表皮葡萄球菌、大肠杆菌均有抑制作用,随着剂量的增加。骨水泥的抗菌活性显著增加,但在一定的观察时间段内,两种抗菌活性剂的变化不同,在1.0g时比较,三氯生明显强于硫酸庆大霉素。空白对照组(不含任何抗生素)无抗菌活性。1.2在相同剂量下24h内,硫酸庆大霉素骨水泥的抑菌环直径与三氯生骨水泥的抑菌环直径无显著差异。在48h后三氯生骨水泥抑菌环直径大于硫酸庆大霉素骨水泥的抑菌环直径,持续时间与硫酸庆大霉素骨水泥对照,其抗菌活性比硫酸庆大霉素平均长48h(p<0.05)。两种骨水泥对革兰氏阳性菌的黏附均显著降低(p<0.05)。但三氯生骨水泥对大肠杆菌的杀菌作用无论从时间起始到杀菌的整个过程都明显不如硫酸庆大霉素。2.两种抗菌活性骨水泥生物力学实验测定分析根据ISO 5833《外科植入物----丙烯酸类树脂骨水泥》标准中规定的两种骨水泥机械性能的测试方法测定含三氯生的骨水泥的物理和力学性能。其一是压力试验,其二是四点弯曲试验。压力检测表明,适量的三氯生的加入不影响骨水泥的抗压强度,将2.0g三氯生混入40g骨水泥中,抗压强度均大于70MPa,好于ISO 5833标准中规定的抗压强度70MPa,和对照组(无抗生素的骨水泥)相似。而根据ISO5833对四点弯曲测试提出的标准,三氯生骨水泥产品均能达到这一标准,弯曲模量(MPa)>1800MPa,弯曲强度(MPa)>50 MPa。结论：1三氯生骨水泥同目前临床上常用硫酸庆大霉素骨水泥相比,抗菌范围广,尤其是对现今临床常见感染菌(金黄色葡萄球菌)有良好的抑菌作用。2三氯生骨水泥同目前临床上常用硫酸庆大霉素骨水泥相比,抗菌剂的缓释效果好,抑菌时间长,由于三氯生是一种具有抗菌活性的杀菌剂,它不同于临床上常用的抗生素,它是单靶点的杀菌剂,因此不像庆大霉素那样很容易产生耐药性,而三氯生则不会。3压力试验和四点弯曲试验表明,加入实验剂量的三氯生的骨水泥的抗压效果与无抗生素的骨水泥相似。弯曲模量和弯曲强度均达标。本实验从体外实验的视角阐述了具有抗菌活性的三氯生骨水泥,与临床上常用的硫酸庆大霉素骨水泥相比具有更强、更持久的杀菌能力,为未来初次人工关节置换手术及关节翻修术后感染的预防和治疗,提供了基础的实验支持。更多还原

【Abstract】 Objective:This study selected one import bone cement without antibiotic activity, Experiment with the powder characteristics of triclosan and gentamicin sulfate antibiotic substances, Three common bacteria infections, staphylococcus aureus, escherichia coli, staphylococcus epidermidis. Respectively, mixing bone cement for different doses of triclosan and gentamicin. Made of tablet of antibacterial activity bone cement. put into three kinds common infectious bacteria culture dish:①to coMPare the diameter of inhibition zone of different time points, Created the drug release law of antibacterial activity of triclosan cement change over time in vitro.②made in accordance with international standards of different doses of bone cement module. By biomechanical stress and elastic modulus tests, Antibacterial activity were coMPared the biomechanical properties of bone cement.Methods:The experiment was conducted in the Orthopaedic Laboratory and Clinical Microbiology Division of People’s Liberation Army General Hospital between 2009-2/2009-10.①Preparation of antibacterial tablets:To triclosan, gentamicin were weighing out 0.5g, 1.0g,1.5g,2.0g and 40g doses of bone cement mixed in sterile conditions, Adding 15mL of sterile liquid ampoule,2min after mixing, adding among the shaping mold, Diameter made of 6mm, the thickness of 3mm of the short cylinder,6 for each dose. Mold is made from high density polyethylene.②preparation of the model of measurement of biomechanical properties:A: determination of compressive strength of bone cement modules:gentamicin sulfate and Triclosan of different doses mixed with cement poured into the cylinder (the length 12mm±0.1mm, diameter 6mm±0.1mm), At 23℃ambient temperature, the preservation of bone cement cylinder. B:Determination of flexural strength of bone cement modules:Mold is made from high density polyethylene, Each mold has a mold trough, about 75mm, width 10mm, depth 3.3mm, a total of six.③inhibition experiments with measured:triclosan and gentamicin sulfate of the different doses (0.5g, 1.0g,1.5g,2.0g) mixed with bone cement, respectively, each made of six specimens, put into three experimental strains, each culture dish placed four different doses of samples,bacteria were incubated at 37℃in 24h.then observe the size of inhibition zone.24h replacement every dish. the inhibition zone were observed at 24h, 48h,72h,96h,1 week, up until diameter the inhibition zone less than 6mm.④biomechanical test:A:The compressive strength of bone cement:for each cylinder, record the force caused by rupture or 2% of the yield strength or the yield point load, That first appeared on the record that, the force divided by the original section of the cylinder,MPa as units of compression strength,Calculate the average 6 cylinder compressive strength. B:Determination of bending strength bone cement: triclosan,gentamicin and bone cement were mixed respectively, Control group, the bone cement were pouring into the mold, after shaping, strip of all the experiments will poured into the four-point bending test device, record deviation from the strip center. increasing force until the test slab fracture. Record the force at fracture.CHISS2004 software was used for statistical analysis, and measurement data were expressed in the form of mean value±standard deviation((?)±s). antibacterial activity of different doses applied analysis of variance between the two groups.Results:1. the role of antibacterial activity of time-dependent bone cement loading with triclosan and gentamicin bone cement.1.1 With the dose increased, bone cement of 0.5～2.0g of triclosan and gentamicin sulfate on Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli was inhibited. The antibacterial activity of bone cement increased significantly, However, in certain period of observation, two different antibacterial agents change, the antibacterial activity of triclosan was stronger than that of gentamicin sulfate in 1.0g. Control group (without any antibiotic bone cement) without antibacterial activity.1.2 The bone cement at the same dose within24h, of gentamicin sulfate and triclosan was no significant difference. After 48h, diameter of inhibition zone of triclosan was larger than the zone diameters of gentamicin sulfate, control duration of the bone cement, the antibacterial activity of triclosan was longer than gentamicin,the average length 48h(p<0.05). Both bone cements against Gram-positive bacteria were significantly decreased adhesion (p<0.05). However, gentamicin sulfate to E. coli bacteria was significantly better than triclosan.2. Biomechanical analysis of two kinds of antibacterial bone cement. according to ISO 5833 "surgical implants-acrylic resin cement" standard, determination of bio-mechanical properties of bone cement loading with triclosan. one is the pressure test, and the second is a four-point bending test. the pressure test showed that adding the right amount of triclosan did not affect the compressive strength of bone cement, 40g to 2.0g triclosan mixing bone cement, the compressive strength were greater than 70MPa, better than the ISO 5833 standard (strength 70MPa), and similar to bone cement without antibiotics. according to ISO 5833 to the four-point bending test, triclosan bone cement product can meet this standard, the bending modulus (MPa)>1800MPa, bending strength>>50 MPa.Conclusion:1 Triclosan bone cement coMPared with Gentamicin bone cement at present study,have a wide range of bacteria, especially in today’s clinical infections bacteria (Staphylococcus aureus) has a good antimicrobial effect.2 Bone cement loading with triclosan Triclosan coMPared with bone cement loading with Gentamicin at present study, effective antimicrobial agent release, antibacterial longer. because triclosan is an antibacterial fungicide, which is different from commonly used clinical antibiotics, It is a single target of the fungicide,therefore, resistance to gentamicin, and triclosan does not.3 Pressure test and four-point bending test showed that the compressive effect of experimental dose similar to bone cement without antibiotics.flexural modulus and flexural strength are up to standard.Our experiment in vivo shows that antibacterial activity of bone cement loading with triclosan offer better than bone cement loading with Gentamicin. bone cement loading with triclosan have a stronger, more durable antibacterial activity. It offers elementary experiment support for prevention of postoperative infection of the first artificial joint replacement and joint revision surgery in the further.更多还原