Objective To design and construct a graphene oxide (GO)/silver nitrate (Ag3PO4)/chitosan (CS) composite coating for rapidly killing bacteria and preventing postoperative infection in implant surgery. Methods GO/Ag3PO4 composites were prepared by ion exchange method, and CS and GO/Ag3PO4 composites were deposited on medical titanium (Ti) sheets successively. The morphology, physical image, photothermal and photocatalytic ability, antibacterial ability, and adhesion to the matrix of the materials were characterized. Results The GO/Ag3PO4 composites were successfully prepared by ion exchange method and the heterogeneous structure of GO/Ag3PO4 was proved by morphology phase test. The heterogeneous structure formed by Ag3PO4 and GO reduced the band gap from 1.79 eV to 1.39 eV which could be excited by 808 nm near-infrared light. The photothermal and photocatalytic experiments proved that the GO/Ag3PO4/CS coating had excellent photothermal and photodynamic properties. In vitro antibacterial experiments showed that the antibacterial rate of the GO/Ag3PO4/CS composite coating against Staphylococcus aureus reached 99.81% after 20 minutes irradiation with 808 nm near-infrared light. At the same time, the composite coating had excellent light stability, which could provide stable and sustained antibacterial effect. ConclusionGO/Ag3PO4/CS coating can be excited by 808 nm near infrared light to produce reactive oxygen species, which has excellent antibacterial activity under light.
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.
ObjectiveTo review the research status of anti-infective graft materials and analyze their application prospects, in order to provide inspiration for the development of anti-infective vascular endograft. MethodThe research on endovascular anti-infective grafts at home and abroad was reviewed. ResultsThe anti-infective capability of endovascular graft could be achieved through main approaches like modification of the bulk material, surface modification, or a combination of both. In terms of bulk material modification, this paper delved into the creation of antibacterial composite materials by incorporating other materials into primary materials like metals (such as Mg, Zn), biologically derived materials (such as chitosan, silk fibroin, bacterial cellulose), and synthetic polymers (such as graphene and its derivatives, polyurethane, polylactic acid). Examples included Mg-Nd-Zn-Zr alloy, bacterial cellulose/chitosan nanocrystal composites, and chitosan/silk fibroin composites. For surface modifications, inorganic coatings (such as silver, copper, and nitrides) and organic coatings (such as antibiotics, antimicrobial peptides, and anti-infection polymers) had shown promising antibacterial effects in experiments. ConclusionsThe future research focus is how to synthesize the composite graft material with the mechanical properties of ordinary graft and the cell, blood compatibility and antibacterial properties through nano technology. At the same time, how to synthesize coatings with stable long-term anti-infection and anti-bacterial biofilm performance is also considered to be an important direction of future research.
ObjectiveThe antibacterial properties of porous medical implant materials were reviewed to provide guidance for further improvement of new medical implant materials.MethodsThe literature related to the antibacterial properties of porous medical implant materials in recent years was consulted, and the classification, characteristics and applications, and antibacterial methods of porous medical implant materials were reviewed.ResultsPorous medical implant materials can be classified according to surface pore size, preparation process, degree of degradation in vivo, and material source. It is widely used in the medical field due to its good biocompatibility and biomechanical properties. Nevertheless, the antibacterial properties of porous medical implant materials themselves are not obvious, and their antibacterial properties need to be improved through structural modification, overall modification, and coating modification.ConclusionAt present, coating modification as the mainstream modification method for improving the antibacterial properties of porous medical materials is still a research hotspot. The introduction of new antibacterial substances provides a new perspective for the development of new coated porous medical implant materials, so that the porous medical implant materials have a more reliable antibacterial effect while taking into account biocompatibility.
摘要:目的：評價圍手術期預防性應用抗菌藥物現狀及合理性。方法：采用回顧性調查的方法，隨機抽查2009年度Ⅰ類切口手術圍手術期病案500份，設計外科圍手術期預防性應用抗生素調查表，對預防用藥的適應證、用藥種類、聯合用藥、給藥時機及持續時間進行統計分析。結果：未使用抗生素5例，預防性使用抗生素495例，其中不合理80例（16.00％）。預防性使用抗生素總品規數為540，其中頭孢菌素類453例（83.89%），青霉素類（包括加酶抑制劑）26例（4.81%），喹諾酮類44例（8.15%）。選用頭孢唑啉鈉178例（32.96%）居第一位，頭孢替唑鈉第二，151例（2796%）。結論：Ⅰ類切口手術患者圍手術期預防性使用抗菌藥物較為合理，但仍存在用藥指征把握不嚴，抗菌藥物的選擇、抗菌藥物使用時間較長等問題，有待進一步規范化管理。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.
The poor mechanical property and vulnerability to bacterial infections are the main problems in clinic for dental restoration resins. Based on this problem, the purpose of this study is to synthesize silver-titanium dioxide (Ag-TiO2) nanoparticles with good photocatalytic properties, and add them to the composite resin to improve the mechanical properties and photocatalytic antibacterial capability of the resin. The microstructure and chemical composition of Ag-TiO2 nanoparticles and composite resins were characterized. The results indicated that Ag existed in both metallic and silver oxide state in the Ag-TiO2, and Ag-TiO2 nanoparticles were uniformly dispersed in the resins. The results of mechanical experiments suggested that the mechanical properties of the composite resin were significantly improved due to the incorporation of Ag-TiO2 nanoparticles. The antibacterial results indicated that the Ag-TiO2 nanoparticle-filled composite resins exhibited excellent antibacterial activities under 660 nm light irradiation for 10 min due to the photocatalysis, and the Ag-TiO2 nanoparticle-filled composite resins could also exhibit excellent antibacterial activities after contact with bacteria for 24 h without light irradiation because of the release of Ag ions. In summary, this study provides a new antibacterial idea for the field of dental composite resins.
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: 探討在闌尾切除術中應用抗菌薇喬縫線以減少闌尾切口感染的可能性。 方法 : 將我院2007年4月至2009年3月所有闌尾切除術病例1425例隨機分為抗菌薇喬縫線組和絲線組,比較其切口感染發生率。 結果 : 統計中按闌尾未穿孔、闌尾穿孔以及總計分別計算切口感染率,在抗菌微喬線組感染率分別為017%、072%、028%,絲線組分別為154%、781%、267%,兩組間分別予以X2檢驗,其〖WTBX〗P 值均小于001,具有顯著性差異。 結論 : 縫線是輔助產生切口感染的一個危險因素,在闌尾切除術中使用抗菌薇喬縫線可以顯著降低切口感染率。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.
ObjectiveTo review antibacterial/osteogenesis dual-functional surface modification strategy of titanium-based implants, so as to provide reference for subsequent research. MethodsThe related research literature on antibacterial/osteogenesis dual-functional surface modification strategy of titanium-based implants in recent years was reviewed, and the research progress was summarized based on different kinds of antibacterial substances and osteogenic active substances. ResultsAt present, the antibacterial/osteogenesis dual-functional surface modification strategy of titanium-based implants includes: ① Combined coating strategy of antibiotics and osteogenic active substances. It is characterized in that antibiotics can be directly released around titanium-based implants, which can improve the bioavailability of drugs and reduce systemic toxicity. ② Combined coating strategy of antimicrobial peptides and osteogenic active substances. The antibacterial peptides have a wide antibacterial spectrum, and bacteria are not easy to produce drug resistance to them. ③ Combined coating strategy of inorganic antibacterial agent and osteogenic active substances. Metal ions or metal nanoparticles antibacterial agents have broad-spectrum antibacterial properties and various antibacterial mechanisms, but their high-dose application usually has cytotoxicity, so they are often combined with substances that osteogenic activity to reduce or eliminate cytotoxicity. In addition, inorganic coatings such as silicon nitride, calcium silicate, and graphene also have good antibacterial and osteogenic properties. ④ Combined coating strategy of metal organic frameworks/osteogenic active substances. The high specific surface area and porosity of metal organic frameworks can effectively package and transport antibacterial substances and bioactive molecules. ⑤ Combined coating strategy of organic substances/osteogenic active substancecs. Quaternary ammonium compounds, polyethylene glycol, N-haloamine, and other organic compounds have good antibacterial properties, and are often combined with hydroxyapatite and other substances that osteogenic activity. ConclusionThe factors that affect the antibacterial and osteogenesis properties of titanium-based implants mainly include the structure and types of antibacterial substances, the structure and types of osteogenesis substances, and the coating process. At present, there is a lack of clinical verification of various strategies for antibacterial/osteogenesis dual-functional surface modification of titanium-based implants. The optimal combination, ratio, dose-effect mechanism, and corresponding coating preparation process of antibacterial substances and bone-active substances are needed to be constantly studied and improved.
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.
