Objective Platelet-rich plasma (PRP) contains high concentrations of platelets and leucocytes, which play a key role in antimicrobial host defense system. To evaluate the antimicrobial efficacy of autologous PRP in vitro and in vivo and to explore the mechanism of action so as to provide the experimental basis for the prevention and treatment of bone infection. Methods PRP was prepared with the method of two centrifugation from 15 health volunteers. Platelet-leukocytegel (PLG) was obtained after activation of PRP with bovine thrombin. Next, PLG was incubated with Staphylococcus aureus (1 × 106 cfu/mL) in vitro compared with PRP, platelet-poor plasma (PPP) and PBS. Samples were taken out after 2, 4, 6, 8, 12, and 24 hours for bacterial culture and colony count. Thirty-six New Zealand adult rabbits, weighing (2.85 ± 0.11) kg, were divided into 4 groups: PLG (n=10), antibiotic (n=10), infection (n=10), and PBS (n=6) groups. The osteomyel itis models were made by injecting 0.1 mL Staphylococcus aureus suspension (1 × 106 cfu/mL) into the tibial canal in PLG group, antibiotic group, and infection group; equal volumes of PBS was injected in PBS group as a control. Autologous PLG was injected immediately after operation in PLG group. Cefazol in (30 mg/kg) was injected through the auricular vein from 1 hour before operation to 72 hours after operation in antibiotic group, once per 8 hours. No treatment was given in infection and PBS groups. The efficacy of PLG for osteomyel itis prophylaxis was evaluated by microbiological, X-ray and histological observation within 28 days. Results The contents of leucocyte and platelet of PRP were 6.2 times and 5.5 times of whole blood, showing signficant differences ((P lt; 0.05); the contents of leucocyte and platelet of PPP were significantly lower than those of whole blood and PRP ((P lt; 0.05). In vitro test showed that PLG had the most obvious bacteriostasis effect. The bacterial count reached a minimum value at 4 hours after incubation in PLG and at 6 hours after incubation in PRP. PPP had slow and no obvious bacteriostasis effect and PBS had no bacteriostasis effect. At 2, 4, 6, 8, 12, and 24 hours of incubation, the bacterial count reduced significantly when compared PLG with PRP and PPP (P lt; 0.05), when compared PRP with PPP (P lt; 0.05). In PLG group and antibiotic group, 1 rabbit died, respectively; 34 rabbits survived to the end of the experiment. There was no significant difference (P gt; 0.05) in temperature, body weight, erythrocyte sedimentation rate and content of leucocyte between 28 days after operation andbefore operation in 4 groups. After 28 days, the X-ray scores were 2.78 ± 1.39, 1.55 ± 1.48, 4.17 ± 1.25, and 0 in PLG, antibiotic,infection, and PBS groups, respectively, which was significantly higher in infection group than in other 3 groups ((P lt; 0.05). Also, the histological scores were 5.89 ± 3.92, 3.00 ± 2.31, 10.33 ± 4.03, and 0, respectively, which was significantly higher in infection group than in other 3 groups (P lt; 0.05), and was significantly lower in antibiotic group than in PLG group ((P lt; 0.05). The results of bacterial culture showed that the infection rates of PLG group (44.4%) and antibiotic group (20.0%) were significantly lower ((P lt; 0.05) than that of infection group (88.9%). The quantitative analysis of bacteria showed that the number of bacteria was signifcantly lower ((P lt; 0.05) in PLG and antibiotic groups than in infection group. Conclusion PRP forms into PLG after activating, it can inhibit Staphylococcus aureus reproduction in vitro and can effectively prevent bone infection in vivo.
摘要:目的: 探讨在阑尾切除术中应用抗菌薇乔缝线以减少阑尾切口感染的可能性。 方法 : 将我院2007年4月至2009年3月所有阑尾切除术病例1425例随机分为抗菌薇乔缝线组和丝线组,比较其切口感染发生率。 结果 : 统计中按阑尾未穿孔、阑尾穿孔以及总计分别计算切口感染率,在抗菌微乔线组感染率分别为017%、072%、028%,丝线组分别为154%、781%、267%,两组间分别予以X2检验,其〖WTBX〗P 值均小于001,具有显著性差异。 结论 : 缝线是辅助产生切口感染的一个危险因素,在阑尾切除术中使用抗菌薇乔缝线可以显著降低切口感染率。Abstract: Objective: To investigate the application of Coated VICRYL Plus Antibacterial suture in order to reduce the possibility of infection of appendectomy incision. Methods : Hospital from April 2007 to March 2009 appendectomy patients in all 1425 cases were randomly divided into Coated VICRYL Plus Antibacterial suture group and silk group,compared to the incidence of incision infection. Results : The statistics are not in accordance with perforated appendicitis, perforated appendicitis, as well as calculation of the total, respectively, incision infection, the infection rate in the Coated VICRYL Plus Antibacterial suture group were 017%, 072%, 028%, silk group were 154%, 781%, 267% between the two groups separately X2 test, the P value of less than 001, with a significant difference. Conclusion : The suture is to assist the incision produced a risk factor for infection in appendectomy,Coated VICRYL Plus Antibacterial suture can be used in a significant reduction in incision infection rates.
摘要:目的：评价围手术期预防性应用抗菌药物现状及合理性。方法：采用回顾性调查的方法，随机抽查2009年度Ⅰ类切口手术围手术期病案500份，设计外科围手术期预防性应用抗生素调查表，对预防用药的适应证、用药种类、联合用药、给药时机及持续时间进行统计分析。结果：未使用抗生素5例，预防性使用抗生素495例，其中不合理80例（16.00％）。预防性使用抗生素总品规数为540，其中头孢菌素类453例（83.89%），青霉素类（包括加酶抑制剂）26例（4.81%），喹诺酮类44例（8.15%）。选用头孢唑啉钠178例（32.96%）居第一位，头孢替唑钠第二，151例（2796%）。结论：Ⅰ类切口手术患者围手术期预防性使用抗菌药物较为合理，但仍存在用药指征把握不严，抗菌药物的选择、抗菌药物使用时间较长等问题，有待进一步规范化管理。Abstract: Objective: To understand the current application of perioperative preventive antibiotics, and their rationality. Methods: Five hundred perioperative records of patients with incision Ⅰ were randomly chosen and surveyed in 2009. A questionnaire for prophylactic use of antimicrobial was designed. The indication of antimicrobial use, the species, combination, timing and drug duration were analyzed. Results: Our of 500, 495 used antimicrobial and 80 were unreasonable; 540 kinds of antimicrobial were used, included cephalosporin 453 cases (83.89%), penicillin class (including plus enzyme inhibitors) in 26 cases (4.81%), quinolone 44 cases (8.15%). Cefazolin sodium (178 patients, 32.96%) ranked first, second was cefazolin sodium (151, 27.96%). Conclusion: Perioperative use of antimicrobial prophylaxis in patients with incision Ⅰ is reasonable, but standardization management should be strengthened in the indication, species, and duration.
Currently, all the conventional antibiotics have developed corresponding drug-resistant pathogenic strains, which have increasingly become a serious threat to people's health. Development of completely new types of antibiotics is one of effective ways to solve the drug resistance issue. Antimicrobial peptides with broad-spectrum antibacterial and antimicrobial activity and wild variety become the ideal alternative to traditional antibiotics. Antimicrobial peptides are derived from wide range of sources, such as plants, animals, and microorganisms. Mechanism of function of the antimicrobial peptides and the investigation approaches of different antimicrobial peptides also vary dramatically. In this paper, we give an overview of preparation, antibacterial mechanisms, and research methodology of antimicrobial peptides.
In order to solve the problem of high cytotoxicity in vitro of nano-silver antibacterial gel, and the problem of large nano-silver particle size and size distribution, this study prepared nano-silver antibacterial gel with better biocompatibility and good antibacterial effect by using physical cross-linking method and using poloxamer as dispersant when prepared nano-silver. In this study, nano-silver was prepared by photo-initiator method and by adding poloxamer as a dispersant, and then UV-visible absorption spectrum test and scanning electron microscopy (SEM) test were carried out using prepared nano-silver mixture and particles after drying respectively. The gel was prepared through adjusting its pH value by using sodium bicarbonate, and then pH value test, SEM test for cross-section of gel, swelling ratio test, viscosity test, inhibition zone test and in vitro cytotoxicity test were carried out. The test results showed that the maximum absorption wavelength of prepared nano-silver, using poloxamer as dispersant and ultra-pure water as solvent, was 414 nm, and the average nano-silver size was about 60 nm. The prepared nano-silver using poloxamer as dispersant had smaller particle diameter and narrower particle size distribution than those using PVP as dispersant. Similarly, the prepared nano-silver using ultra-pure water as solvent also had smaller particle diameter and narrower particle size distribution than those using distilled water as solvent. The pH value of the prepared gel was between 5.8~6.1. The dried gel section had many holes. The water absorption of gel was fine and the viscosity of gel was fit to coat on the gauze. In addition, the prepared gel with nano-silver had greater ability to inhibit Escherichia coli and Staphyloccocus aureus at the concentrations of 24, 18 and 12 μg/mL. And the biocompatibility of the prepared gel with nano-silver was good when the concentration below 24 μg/mL. Based on the above features, the nano-silver antibacterial gel could be used in the treatment of burn or other wounds.
Objective To extend its application in the field of bone repair by adding oxygen-carboxymethylated chitosan (O-CMC) and gentamicin for modification of the calcium sulfate cement (CSC). Methods The O-CMC/CSC was prepared by adding O-CMC with different concentrations (0.1wt%, 0.3wt%, 0.5wt%, 0.7wt%, and 1.0wt%) in the CSC liquid phase. The effect of O-CMC on the CSC was evaluated by testing the injectability, compressive strength, degradation rate, pH value, cytotoxicity and osteogenesis. After the optimal concentration of O-CMC was determined, gentamicin with different concentrations (0.5wt%, 1.5wt%, and 2.5wt%) was added in the O-CMC/CSC, and then the compressive strength and antibacterial properties were investigated. Results After adding O-CMC in the CSC liquid phase, the injection time of O-CMC/CSC was increased to more than 5 minutes; it significantly prolonged with increased concentration of O-CMC (P<0.05). The compressive strength of the modified bone cement was in the range of 11-18 MPa and it was the highest when the concentration of O-CMC was 0.5wt% (P<0.05). The degradation rate of O-CMC/CSC was not influenced obviously by O-CMC (P>0.05). The pH value was in the range of 7.2-7.4 and Ca2+ concentration was in the range of 6-8 mmol/L.In vitro mineralization experiment indicated that the induced mineralization ability of O-CMC/CSC was much higher than that of pure CSC. The 0.5wt% O-CMC/CSC had the best performance; the compressive strength of the composite bone cement was above 5 MPa after gentamicin was added, which had antibacterial effect. Conclusion O-CMC is able to effectively improve the injection, compressive strength, and osteogenic activity of CSC; in addition, antibacterial properties is obtained in the CSC after adding gentamicin.
The objective of the study is to analyze the biological characteristics and stability of the linear derivative Bac2a from bactenecin, compared with the control peptide melittin. The secondary structure, antibacterial activity, hemolytic activity, cell toxicity and stability of the Bac2a were determined by circular dichroism spectroscopy, broth micro-dilution method and MTT assay. The results showed that Bac2a was a nonregular curl in aqueous solution, however, it was an α-helix structure in the hydrophobic environment. The minimal inhibitory concentration (MIC) of Bac2a ranged from 2 to 32 μmol/L, so the bacteriostatic activity of Bac2a was strong. The hemolytic rate was only 14.81% when the concentration of Bac2a was 64 μmol/L, which showed that the hemolytic rate of Bac2a was low. The therapy index of Bac2a was 3.26, and the cytotoxicity was relatively low, thus the cell selectivity was relatively high. In addition, with the heating treatment of 100℃ for 1 h, Bac2a still possessed rather a high antibacterial activity and showed a good heating stability. In a word, Bac2a has good application prospects in food, medicine and other fields, and is expected as a substitute for traditional antibiotics.
Objective To investigate the research progress of drug-loaded antibacterial coating of orthopedic metal implants in recent years. Methods The recent literature on the drug-loaded antibacterial coating of orthopedic metal implants were reviewed. The research status, classification, and development trend of drug-loaded antibacterial coating were summarized. Results The drug-loaded antibacterial coating of orthopedic metal implants can be divided into passive release type and active release type according to the mode of drug release. Passive drug release coating can release the drug continuously regardless of whether the presence of bacteria around the implants. Active drug release coating do not release the drug unless the presence of bacteria around the implants. Conclusion The sustained and stable release of drugs is a key problem to be solved in various antibacterial coatings research. The intelligent antibacterial coating which release antibiotics only in the presence of bacteria is the future direction of development.
Objective To systematically review the efficacy of long-acting antibacterial material in the prevention of secondary urinary infection. Methods PubMed, The Cochrane Library, CNKI, CBM, WanFang Data and VIP databases were electronically searched to collect randomized controlled trials (RCTs) on the efficacy of long-acting antibacterial material in the prevention of secondary urinary infection from inception to November, 2016. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies, then, meta-analysis was performed by using RevMan 5.3 software. Results A total of 16 RCTs were included. The results of meta-analysis showed that: the long-acting antibacterial material group was superior to the general intervention group in morbidity of secondary urinary infection (Peto OR=0.17, 95%CI 0.13 to 0.23, P<0.000 01), and bacterial positive rate of secondary urinary infection (Peto OR=0.15, 95%CI 0.08 to 0.27,P<0.000 01). Conclusion Current evidence shows that long-acting antibacterial material can effectively reduce the infection rates of secondary urinary infection. Due to limited quality and quantity of the included studies, more high quality studies are needed to verify the above conclusion.
5–20 wt% trimethoxysilylpropyl octadecyldimethyl ammonium chloride (QAS) was used to modify Poly (ε-caprolactone) (PCL)-gelatin hybrid to fabricate non-leaching antibacterial nanofiber membranes (PG-Q) by electrospinning. The results from scanning electron microscopy (SEM) and transmission electron microscopy (TEM) indicated that the QAS leaded to phase separation between the QAS and PCL. Hydrophilic test demonstrated that the PG-Q nanofiber membranes had hydrophobic surface, which was help for peeling off the dressing from the wound. Additionally, the physical and chemical cross-linking between the QAS/PCL and QAS/gelatin were confirmed by Fourier transform infrared (FTIR), which were good for long lasting antibacterial effect. The PG-Q membranes also showed excellent cell-biocompatibility. Furthermore, compared with pure PCL nanofiber membrane, the PG-Q nanofiber membranes, especially PG-Q15 (QAS: 15 wt%) and PG-Q20 (QAS: 20 wt%), showed a considerable increase in the bacteriostatic rate of S. aureus and P. aeruginosa (more than 99% after 12 h). Therefore, electrospinning non-leaching antibacterial nanofiber membranes could be an optimal choice for antibacterial wound dressing.