In vitro antibacterial efficacy of MONOCRYL plus antibacterial suture (Poliglecaprone 25 with triclosan)

BACKGROUND: This study evaluated the in vitro efficacy of poliglecaprone 25 suture with triclosan against gram-positive and gram-negative bacteria. METHODS: Poliglecaprone 25 sutures with and without triclosan were tested for in vitro efficacy against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis, methicillin-resistant Staphylococcus epidermidis (MRSE), Klebsiella pneumoniae, and Escherichia coli by a zone of inhibition assay. The suture also was tested against Escherichia coli in a colonization assay in a dynamic model simulating in vivo conditions. An in vitro triclosan diffusion assay and a sustained efficacy assay were performed by concurrent high-performance liquid chromatography and zone of inhibition assay. To assess stability, antibacterial efficacy testing was performed on samples held more than five months at elevated temperature. RESULTS: Poliglecaprone 25 suture with triclosan demonstrated significant in vitro efficacy against a range of bacteria. The suture sustained in vitro efficacy for 11 days, corresponding to the in vitro triclosan diffusion profile. CONCLUSION: Triclosan reduced in vitro colonization of poliglecaprone 25 suture by several strains of bacteria compared with untreated control sutures.     

In vivo antibacterial efficacy of MONOCRYL plus antibacterial suture (Poliglecaprone 25 with triclosan)

BACKGROUND: This study evaluated the ability of poliglecaprone 25 suture with triclosan to inhibit bacterial colonization by Escherichia coli and Staphylococcus aureus in mouse and guinea pig models. METHODS: Test and control sutures (3-4 cm) were implanted subcutaneously in the dorsal-lateral regions (control on the left side, test on the right side, approximately 3-5 cm apart) in 10 female Hartley guinea pigs (300-400 g) and 10 Swiss Webster mice (20-35 g) via a 20-gauge catheter. The test material was poliglecaprone 25 suture with triclosan (2-0, undyed), and the control material was poliglecaprone 25 suture (2-0, undyed). In the guinea pig model, each implantation site was challenged directly with 4x10(5) colony-forming units (cfu) of S. aureus, whereas in the mouse model, each implantation site was challenged directly with 1.3x10(7) cfu of E. coli through an indwelling catheter. At 48 h post-implantation, the control and test sutures were explanted, and bacterial enumeration was performed. RESULTS: There was a significant difference (p < 0.05) in the number of bacteria recovered in the study groups 48 h post-implantation. Poliglecaprone 25 suture with triclosan produced a 3.4-log reduction in S. aureus and a 2-log reduction in E. coli compared with standard poliglecaprone 25 suture without triclosan under the same challenge conditions. The difference between the study groups in the number of bacteria recovered was significant (p < 0.05). CONCLUSION: Poliglecaprone 25 suture with triclosan inhibited bacterial colonization of the suture compared with untreated suture after direct in vivo challenge with S. aureus and E. coli in animal models.     

去甲万古霉素载药涤纶血管材料体外抗菌活性测定

目的：评价去甲万古霉素（NV）载药涤纶血管材料体外抗菌活性。方法：血管材料剪成直径6mm圆形。分别制成空白涤纶材料和载药（NV）涤纶材料，分别于0，7，14，28d取样观察体外缓释性能。选用耐甲氧西林表皮葡萄球菌（MRSE）和耐甲氧西林金黄色葡萄球菌（MRSA）作为试验菌，分别观察空白和载药涤纶血管材料0．7，14，28d和快慢相的抗菌效果。结果：两种细菌0，7，14，28d载药涤纶材料-细菌混合培养液的菌落数显著少于空白涤纶材料-细菌混合培养液（P均〈0．001）。结论：体外试验证实载NV涤纶材料MRSE和MRSA具有抗菌作用，且可持续维持28d。提示该载药材料具有持久抗菌活性，可用于制备抗感染血管移植物。     

Bacterial adherence to surgical sutures: can antibacterial-coated sutures reduce the risk of microbial contamination?

BACKGROUND: Surgical site infections are associated with severe morbidity and mortality. The role of surgical sutures in the etiology of surgical site infection has been the objective of discussion for decades. This study used a standardized in vitro microbiologic model to assess bacterial adherence and the antibacterial activity of a triclosan-coated polyglactin 910 (braided) suture against selected Gram-positive and Gram-negative clinical isolates that may infect surgical wounds. STUDY DESIGN: Standardized cultures (2.0 log(10) colony forming units/mL and 5.0 log(10) colony forming units/mL of three clinical strains, Staphyllococcus aureus (methicillin-resistant S aureus [MRSA]), S epidermidis (biofilm-positive) and Escherichia coli (extended-spectrum beta-lactamase [ESBL]-producer) were inoculated to triclosan-coated and noncoated polyglactin 910 sutures to evaluate comparative adherence of bacterial isolates to the antibacterial coated and noncoated surgical sutures; to assess the impact of serum proteins (bovine serum albumin) on antibacterial activity of triclosan-coated suture; and to document the duration of antibacterial activity of the triclosan-coated material. Selected suture samples were prepared for scanning electron microscopy to demonstrate bacterial adherence. RESULTS: Substantial (p < 0.01) reductions in both Gram-positive and Gram-negative bacterial adherence were observed on triclosan-coated sutures compared with noncoated material. Pretreatment of surgical sutures with 20% BSA did not diminish antibacterial activity of the triclosan-coated braided device compared with noncoated suture (p < 0.01), and antibacterial activity was documented to persist for at least 96 hours compared with controls (p < 0.01). CONCLUSIONS: The in vitro model demonstrated a considerable reduction (p < 0.01) in Gram-positive and Gram-negative bacterial adherence to a triclosan-coated braided suture, which was associated with decreased microbial viability (p < 0.001). Because bacterial contamination of suture material within a surgical wound may increase the virulence of a surgical site infection, treating the suture with triclosan provides an effective strategy for reducing perioperative surgical morbidity.     

Experimental efficacy study of coated VICRYL plus antibacterial suture in guinea pigs challenged with Staphylococcus aureus

BACKGROUND: This study evaluated the ability of coated polyglactin 910 suture with triclosan (Coated VICRYL Plus Antibacterial) suture to inhibit the colonization of bacteria on the suture after direct in vivo inoculation challenge with Staphylococcus aureus utilizing a guinea pig model. METHODS: One control suture (4-5 cm) and one test suture (4-5 cm) were implanted subcutaneously in the dorsal-lateral regions (control on the left side, test on the right side, approximately 5 cm apart) in 16 female Hartley guinea pigs (300-400 g) via a 20-gauge catheter. Each implantation site was challenged directly with 2.1 x 10(4) colony forming units (cfu) of Staphylococcus aureus through the indwelling catheter. The test material was coated polyglactin 910 suture with triclosan (2-0, dyed), and the control material was coated polyglactin 910 suture (2-0, undyed). At 48 h, suture articles were explanted and a bacterial enumeration assay was performed. RESULTS: There was a significant difference (p < 0.05) in the number of bacteria recovered between the study groups at 48 h post-implantation. The mean recovery for test sutures was 559 cfu, and the mean recovery for control sutures was 16,831 cfu. Coated polyglactin 910 suture with triclosan provided a 30.5-fold (96.7%) reduction in the number of recovered bacteria compared to standard coated polyglactin 910 suture. CONCLUSIONS: This study demonstrates that coated polyglactin 910 suture with triclosan inhibits bacterial colonization of suture after direct in vivo challenge with S. aureus in a guinea pig model.     

Limitations in the use of rifampicin-gelatin grafts against virulent organisms

OBJECTIVE: Efficacy and duration of antibacterial activity of rifampicin-gelatin grafts against virulent organisms were evaluated in an animal model.Materials And Methods: Rifampicin-gelatin grafts were prepared with impregnation of Gelseal (Vascutek Ltd, Scotland) graft in 1 mg/mL rifampicin solution. Rifampicin-gelatin grafts (6 cm long; n = 24) and plain Gelseal grafts as controls (n = 4) were implanted into the canine abdominal aorta with inoculation of Staphylococcus epidermidis, Escherichia coli, or methicillin-resistant Staphylococcus aureus (MRSA), and the rifampicin-gelatin grafts were retrieved after 1 to 4 weeks. Disks cut from the retrieved rifampicin-gelatin grafts were placed on agar plates streaked with one of the organisms, and the graft antibacterial activity was assessed with the width of the inhibition zone. RESULTS: In in vitro tests, initial inhibition zones (inhibition zone of 24 hours after incubation) of rifampicin-gelatin grafts against S epidermidis, MRSA, and E coli were 40.0 +/- 0.3 mm, 36.0 +/- 0.2 mm, and 11.8 +/- 0.1 mm, respectively. In the implantation, S epidermidis -inoculated rifampicin-gelatin grafts had no findings of graft infection, and no colony growth was recognized on the plates streaked with the perigraft fluids. Initial inhibition zones of S epidermidis -inoculated rifampicin-gelatin grafts retrieved at 1 or 2 weeks were 20.1 +/- 1.1 mm and 7.6 +/- 1.0 mm, respectively. In E coli -inoculated and MRSA-inoculated rifampicin-gelatin grafts, all of the eight animals had perigraft abscess, and blood culture test results probed septicemia in five animals with patent grafts at death. Inhibition zones against E coli or MRSA were not formed on the plates streaked with the same organism, whereas initial inhibition zones of E coli -inoculated and MRSA-inoculated rifampicin-gelatin grafts on S epidermidis -streaked plates were 8.0 +/- 0.2 mm and 18.5 +/- 0.5 mm, respectively. In the MRSA group, however, recolonization of high minimal inhibitory concentration strains developed within the inhibition zones as early as 24 hours. Histologically, neither organisms nor inflammatory cells were found in S epidermidis -inoculated rifampicin-gelatin grafts and tissue ingrowth was recognized at 2 to 4 weeks, whereas E coli -inoculated and MRSA-inoculated rifampicin-gelatin grafts had aggressive neutrophil infiltration into the graft interstices, revealing establishment of uncontrollable graft infection. CONCLUSION: These results suggested that rifampicin-gelatin grafts are clearly valid for S epidermidis infection, whereas no efficacy was recognized against either MRSA or E coli graft infection because of early development of high minimal inhibitory concentration MRSA strains or poor susceptibility.     

含与不含乙二酸四乙酸二钠丙泊酚体外抑菌作用研究

目的比较含和不含乙二酸四乙酸二钠(EDTA)的丙泊酚对医院内感染常见细菌的生长抑制作用。方法实验分为四组:A组使用含0.005%EDTA丙泊酚注射液,B组使用不含EDTA丙泊酚注射液,C组使用不含EDTA丙泊酚中/长链脂肪乳注射液,D组使用无菌生理盐水。将甲氧西林敏感、耐药金黄色葡萄球菌、表皮葡萄球菌;万古霉素敏感、耐药屎肠球菌;产与不产超广谱β-内酰胺酶大肠埃希菌、肺炎克雷伯菌以及亚胺培南敏感、耐药铜绿假单胞菌、鲍曼不动杆菌等16株细菌分别与上述液体混合孵育,比较6、12、24和48h孵育后菌落数与起始菌落数的差值。采用菌落计数法绘制细菌生长曲线,统计分析采用协方差分析模型。结果所测16株细菌接种量在101～102CFU/ml和105～106CFU/ml时,室温(22.5℃)孵育情况下,A组对所测菌株均有很好抑菌作用,经48h孵育,活菌数量较起始时普遍减少,且基本没有增加。特别对于大肠埃希菌,活菌数量可下降2个log值以上。A组在各时点均明显优于B、C、D三组(P<0.0001)。结论含EDTA丙泊酚体外可有效抑制医院内感染常见细菌的生长,提示含EDTA丙泊酚比不含EDTA的丙泊酚可能更有效减少麻醉相关的感染。     

Initial evaluation of absorbable polydioxanone suture for peripheral vascular surgery

The long-term integrity of an autogenous vascular anastomosis is primarily dependent on the strength of tissue healing; therefore permanent mechanical support of an autogenous anastomosis with sutures is unnecessary. In this study we evaluated monofilament absorbable polydioxanone as an alternative to polypropylene for suturing autogenous vascular tissue during adult peripheral vascular operations. We used polydioxanone suture for 21 vascular procedures in 20 patients. We evaluated suture handling characteristics during operation and then followed patients with clinical assessments and serial duplex scans to monitor for pseudoaneurysms, anastomotic narrowing, and vessel patency. Indications for surgery included limb salvage (67%), dialysis access (23%), traumatic arteriovenous fistula and claudication (5% each). The operative procedures included infrainguinal bypass (57%), arteriovenous fistula formation (24%), thromboembolectomy (14%), and arteriovenous fistula repair (5%). Polydioxanone sutures were placed in 39 separate test sites (35 arterial, 4 venous). No deaths occurred during operation. Polydioxanone suture was found to have handling characteristics similar to polypropylene. During mean patient follow-up of 7.2 +/- 0.6 months, we found no cases of anastomotic narrowing or pseudoaneurysms. Actuarial test site patency at 1, 3, and 6 months was 97%, 97%, and 86%, respectively. Polydioxanone suture has handling properties that are acceptable for use in vascular applications, and it provides adequate mechanical support for sutured vessels to heal. A randomized trial comparing polydioxanone with polypropylene suture will be necessary to determine whether the lack of permanent foreign material in vascular anastomoses can improve long-term patency.     

Bactericidal activity of preservative-free bupivacaine on microorganisms in the human skin flora

Background: The rate at which the bactericidal activity of preservative-free bupivacaine develops at body temperature and at room temperature is not known. We studied the bactericidal activity of preservative-free bupivacaine on two strains of methicillin-resistant Staphylococcus aureus (MRSA), two strains of methicillin-susceptible S. aureus (MSSA), and each of Staphylococcus epidermidis and Escherichia coli .
Methods: The pathogen was exposed to 0.5% bupivacaine for 1, 3, 6, 12, and 24 h at 37°C and room temperature. In addition, each strain of MRSA, MSSA, and S. epidermidis was exposed to distilled water, and 0.125%, 0.25%, 0.5%, and 0.75% bupivacaine at 37°C. The inocula from the suspensions were cultured for 48 h at 37°C.
Results: The 1- through 24-h exposures of 4 strains of S. aureus to 0.5% bupivacaine at room temperature reduced the colony count by 21.7%, 34.7%, 51.1%, 65.6%, and 81.1%, respectively, and the exposure at 37°C reduced the count by 34.1%, 50.8%, 66.3%, 94.5%, and 96.0%, respectively. The differences were significant at all exposure times ( P <0.001, respectively). No organisms grew in the strain of E. coli after 24-h exposure and in the strain of S. epidermidis after 12- and 24-h exposures at 37°C. The percent change from controls in the strains of E. coli and S. epidermidis was significantly higher than that in the strains of S. aureus at all exposure times at room temperature and 37°C ( P <0.0001, respectively). Higher concentrations of bupivacaine were associated with lower colony count.
Conclusion: Our results show that preservative-free bupivacaine possesses a temperature- and concentration-dependent bactericidal activity, and S. aureus is more resistant to the bactericidal activity of bupivacaine than are S. epidermidis and E. coli .     

Development of an infection-resistant LVAD driveline: a novel approach to the prevention of device-related infections.

BACKGROUND: Infection remains the single most important challenge to extended left ventricular assist device (LVAD) use and often arises from the percutaneous driveline exit site. We evaluated the ability of an LVAD driveline prototype impregnated with chlorhexidine, triclosan, and silver sulfadiazine to resist bacterial and fungal colonization. METHODS: The spectrum and duration of antimicrobial activity were evaluated in vitro by daily transfer of driveline segments embedded on agar plates inoculated with 10(8) colony-forming units (CFU) of Staphylococcus aureus (S. aureus), Staphlococcus epidermidis, Enterobacter aerogenes, Psuedomonas aeruginosa, and Candida albicans, and then measuring zones of inhibition around the sample subsequent to 24 hours of incubation at 37 degrees C. Antimicrobial activity was demonstrated against all organisms for greater than 14 days, and for over 21 days for gram-positive bacteria. To demonstrate in vivo efficacy of the treated driveline, 3-cm segments of driveline were implanted in the dorsal and ventral surface of rats. The exit site was inoculated with 10(6) CFU of S. aureus. After 7 days, driveline segments were aseptically explanted and assayed for bacterial colonization and retention of antimicrobial activity. One hundred percent of control segments were colonized (10(5) CFU S. aureus/cm) as against 13% of the test explants (< or = 330 CFU/cm; p < 0.0001). RESULTS: Subcultures of the insertion site and driveline pocket tissue resulted in 10(3) to 10(5) CFU per swab culture for control rats and 0 to 10(2) CFU/swab for test animals. Test drivelines retained 80% of anti-S. aureus activity. Gross and histological examination of the driveline and surrounding pocket revealed minimal tissue reactivity with positive signs of tissue ingrowth. CONCLUSION: An antimicrobial driveline may prevent early infections and facilitate ingrowth of tissue to provide long-term stability and protection against late infection.     

Polydioxanone in digestive surgery. An experimental study

An experimental study was carried out to analyze the reaction of polydioxanone suture. Two hundred ten single layer colonic anastomoses were performed in rats and histopathologically studied at nine different times between the 2nd and 180th postoperative days. Eighteen of 105 abdominal wound closures were studied in the same way between the 7th and 90th days. Polydioxanone was resorbed slowly in approximately 6 months with minimum inflammation. We believe that polydioxanone is actually the suture material of choice for all biliary and biliodigestive sutures.     

Bacterial adhesion to suture material in a contaminated wound model: Comparison of monofilament,braided, and barbed sutures

Contaminated suture material plays an important role in the physiopathology of surgical site infections. Recently, suture material has been developed characterized by barbs projecting from a monofilament base. Claimed advantages for barbed sutures are a shortened wound closure time and reduced maximum wound tension. It has also been suggested that these sutures would be advantageous microbiologically. The aim of this study was to test the microbiological characteristics of the barbed Quill in comparison to the monofilament Ethilon II and the braided sutures Vicryl and triclosan‐coated Vicryl Plus. In our study, sutures were cultivated on color‐change agar with Staphylococcus aureus , Staphylococcus epidermidis , Enterococcus faecium , Escherichia coli , and Pseudomonas aeruginosa and the halo size was measured. In a second study arm with longer cultivation bacterial growth was followed by antibiotic treatment. Ethilon II and Quill showed good comparable results, whereas large halos were found around Vicryl. Vicryl Plus results depended on triclosan sensitivity. After longer bacterial cultivation and antibiotic treatment, halos were up to 3.6 times smaller on Quill than on Vicryl (p < 0.001), but 1.4 times larger than on Ethilon II (p < 0.001) regarding S. aureus . Confocal microscopy analysis showed bacterial colonization between the braided filaments on Vicryl and beneath the barbs on Quill. From a microbiological perspective, barbed sutures can be recommended in aseptic surgery, but should only be used carefully in septic surgery. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:925–933, 2017.

     

Inflammatory synovial fluid and absorbable suture strength

The effect of inflammatory synovial fluid upon several absorbable sutures commonly used for meniscus repair was studied by implanting lengths of these sutures into unstable, arthritic rabbit knees and, after varying lengths of time (1-6 weeks), testing their breaking strength. Both polyglactin-910 (Vicryl) and polyglycolic-acid (Dexon) sutures retained only minimal breaking strength 3 weeks after implantation. Chromic gut sutures demonstrated a steady reduction in breaking strength until they retained only 6% of their original strength at 5 weeks and none at 6 weeks. Polydioxanone (PDS) sutures began to lose breaking strength at 2 weeks and retained only 40% of their original strength 5 weeks after implantation. The rate of loss in polydioxanone breaking strength was faster in inflammatory synovial fluid than previously reported in the normal synovial joint. Braided polyester sutures (Mersiline) showed no loss of breaking strength over the duration of this test. While the choice of suture is only one variable influencing the outcome of a meniscus repair, this study demonstrates that only polydioxanone and green braided polyester sutures retain any strength 6 weeks after implantation (the time of immobilization commonly recommended for meniscal repairs). Complete meniscal healing can require several months. In the absence of compelling evidence to the contrary, the use of nonabsorbable suture materials for meniscal repair seems the most appropriate choice.     

Resistance and new antibiotic strategies. New antistaphylococcal antibiotics

INJECTABLE SPECTROGRAMIN: Combination regimens using quinupristin/dafopristin with either gentamicin or vancomycin have powerful bactericidal activities (even against quinupristin-resistant strains) against methicillin-resistant Staphylococcus aureus (MRSA) in a model of experimental endocarditis in the rabbit. In clinical trials, quinupristin/dalfopristin is becoming a therapeutic alternative to consider after failure of conventional antistaphylococcal treatments. NEW GENERATION CEPHALOSPORINS: These new cephalosporins, particularly C-3 pyridinium-thiomethyl-cephalosporins, new (3-dithiocarbamoyl) cephalosporins, and a series of new compounds with high affinity for MRSA PLP2a, are particularly active against MRSA and are unaffected by beta-lactamases. A NEW CARBAPENEM: This new antibiotic has a wide bactericidal effect against Gram-positive organisms and is active against MRSA as well as penicillin-resistant S. pneumoniae. NEW FLUOROQUINOLONE DERIVATIVES: In vitro, these new derivatives have been found to be active against MRSA, pneumococci non-sensitive to ciprofloxacin, and Bacteroides fragilis, Mycobacterium tuberculosis, Chlamydia pneumoniae.     

Strength retention of chromic gut and monofilament synthetic absorbable suture materials in joint tissues

The rate at which absorbable sutures lose their mechanical strength in vivo is particularly important in orthopedic applications where high physical loads, often increased by early mobilization, severely test the strength of sutures. The failure load and maximum tensile strength of chromic catgut and two monofilament absorbable synthetic suture materials (polydioxanone and polytrimethylene carbonate) were measured up to six weeks after implantation in sheep as: (1) a suture securing a synovial incision and (2) coils located either within the synovial cavity of the knee or intramuscularly. Although all synovial wounds healed satisfactorily, the performances of the different materials varied. The strength of chromic gut was largely lost within a week and fragmentation occurred at Week 4. The synthetic materials lost their strength relatively slowly. Polytrimethylene carbonate degraded in a linear manner, remaining intact but with little strength by Week 6. Polydioxanone, though losing strength at a slower rate, tended to fragment early, which may be of clinical importance in situations of delayed wound healing.     

Linezolid alone and in combination with rifampicin prevents experimental vascular graft infection due to methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis

BACKGROUND: In this report we describe the in vivo antibacterial activity of linezolid in an experimental graft infection model in rats and compare it with teicoplanin. The objective of this study was also to determine the effects of the interaction of linezolid when it was combined with rifampicin and test this effect against strains of methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis. MATERIALS AND METHODS: Graft infections were established in the subcutaneous tissue of 130 Wistar rats by implantation of Dacron grafts followed by a topical inoculation with 2 x 10(7) CFU of clinical isolates of MRSA and MRSE. The study included a control group and six groups for each of the staphylococcal strains: an inoculated group that did not receive any antibiotic prophylaxis, two inoculated groups that received intraperitoneal prophylaxis with teicoplanin or linezolid alone, an inoculated group that received rifampicin-soaked grafts, and two inoculated groups that received a combination prophylaxis consisting of intraperitoneal teicoplanin or linezolid and rifampicin-soaked grafts. RESULTS: There was a reduction in the quantitative bacterial graft cultures in all prophylaxis groups when compared with inoculated control groups. There was not a statistically significant difference between linezolid and teicoplanin prophylaxis groups. The best results were obtained by a combination of rifampicin-soaked grafts with linezolid or teicoplanin. CONCLUSIONS: We found no evidence to suggest that linezolid differs from teicoplanin regarding effectiveness in the prevention of prosthetic vascular graft infection. Linezolid plus rifampicin and teicoplanin plus rifampicin are demonstrated to be valuable prophylactic regimens.     

248株血液标本检出细菌临床特征及耐药性分析

目的了解血液感染常见细菌分布及耐药特点,为临床血液感染治疗提供实验依据。 方法回顾性分析2010年3月至2013年10月临床阳性血培养资料。 结果共检出细菌248株,分离率排前3位的依次是大肠埃希菌（40.73%）、表皮葡萄球菌（19.76%）和肺炎克雷伯菌（9.27%）。产超广谱β-内酰胺酶（ESBLs）的大肠埃希菌及肺炎克雷伯菌检出率分别为44.55%和20.69%,产酶菌株耐药性严重,检出亚胺培南耐药和美罗培南耐药的大肠埃希菌。甲氧西林耐药金黄色葡萄球菌（MRSA）和甲氧西林耐药表皮葡萄球菌（MRSE）检出率分别为46.67%和69.39%,未发现万古霉素、替考拉宁耐药菌株,葡萄球菌耐药率较低的药物还有利奈唑胺和奎奴普丁-达福普丁。 结论血液感染细菌以肠杆菌科细菌为主,敏感药物为碳青霉烯类。应加强血液感染监测,及时了解其病原菌分布与耐药特点,制定有效的抗菌治疗方案,提高治愈率。     

The EmulSiv™ filter removes microbial contamination from propofol but is not a substitute for aseptic technique

PURPOSE: To evaluate the ability of the EmulSiv filter (EF) to remove extrinsic microbial contaminants from propofol. METHODS: Aliquots of Staphylococcus aureus (S. aureus), Candida albicans (C. albicans), Klebsiella pneumoniae (K. pneumoniae), Moraxella osloensis (M. osloensis), Enterobacter agglomerans (E. agglomerans), Escherichia coli (E. coli), Serratia marcescens (S. marcescens), Moraxella catarrhalis (M. catarrhalis), Haemophilus influenzae (H. influenzae) and Campylobacter jejuni (C. jejuni) were inoculated into vials containing 20 mL of sterile propofol. The unfiltered inoculated propofol solutions served as controls. Ten millilitres and 20 mL samples of the inoculated propofol were filtered through the EF. All solutions were then subplated onto three culture plates using a precision 1 micro L calibrated platinum loop and incubated. The number of colony forming units (CFU) were counted. Data were analyzed using a one-sample t test, and a P value of less than 0.05 was selected as the level of statistical significance. RESULTS: The EF was able to completely remove CFU of S. aureus, C. albicans, K. pneumoniae, M. osloensis, E. agglomerans, E. coli, S. marcescens, and M. catarrhalis (P < 0.05). A small number of H. influenzae CFU were able to evade filtration in both the 10 mL and 20 mL samples. C. jejuni CFU were able to evade filtration in only the 10 mL sample. CONCLUSIONS: The EF removes the majority of microbial contaminates from propofol with the exception of H. influenzae and C. jejuni. Although the EF is capable of removing most of the microbial contamination produced by H. influenzae and C. jejuni, a few CFU are capable of evading filtration. Consequently, even the use of a filter capable of removing microbial contaminants is not a substitute for meticulous aseptic technique and prompt administration when propofol is used.     

Antibacterial activity of positive and negative polarity low-voltage pulsed current (LVPC) on six typical Gram-positive and Gram-negative bacterial pathogens of chronic wounds

The positive effect of electrical stimulation (ES) on wound healing has been shown in vitro and in vivo. On the basis of increased blood flow, protein denaturation, and stimulation of cellular defense, an antibacterial effect of ES is to be expected. Although the antibacterial effect of ES already has been demonstrated in vitro, little attention has been paid to the direct antibacterial effect of changing polarity of the applied current. The aim of this study was to investigate the antibacterial effect of positive and negative monophasic low-voltage pulsed current on typical Gram-positive and Gram-negative pathogens of chronic wounds. Using the Dermapulse-System, three Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae) and three Gram-positive (Staphylococcus aureus, Staphylococcus epidermidis, Escherichia faecium) organisms were tested against positive and negative polarity low voltage pulsed current. All tested organisms were significantly reduced by ES. The reduction differed significantly between positive polarity and control and negative polarity and control, with the highest log10 reduction factor (RF) achieved with positive polarity. Using positive polarity, the maximum RF was measured for E. coli (median log10 RF 0.83; 25th percentile 0.59, 75th percentile 0.98) and the lowest for S. epidermidis (median log10 RF 0.20; 25th percentile 0.17, 75th percentile 0.24). Yet, there was no significant difference with positive ES against Gram-positive or Gram-negative organisms.     

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??Surveillance of bacterial distribution and durg resistance in bloodstream infections inpatients of surgical depatement of Peking University People's Hospitel during 2008-2011 JIANG Ke-wei*, LV You,GUO Peng, et al. *Department of Gastrointestinal Surgery??Surgical Oncology Laboratory??Peking University People’s Hospital, Bejing 100044??China
Corresponding author??WANG Shan, E-mail??Dr.wangshan@sohu.com
Abstract Objective To investigate the pathogens distribution and drug resistance in patients with bloodstream infections during 2008-2011 in Peking University people's hospital and provide the basis for clinical appropriate antimicrobial therapy. Methods Bacterial identification and antibiotic susceptibility testing were initially performed using BacT/ALERT 3D automatic culture system??VITEK-2 system for blood samples of surgical department??and Statistical analysis was performed using the software WHONET 5.6 and SPSS 16.0. Results A total 358 strains isolated from 4074 blood samples, including 166 Gram-negative strains(46.4%), 137 Gram-positive strains(38.3%) and 32 fungal strains(8.9%). Escherichia coli(19.8%),Klebsiella pneumoniae (11.2%),Staphylococcus epidermidis(10.1%), Staphylococcus hominis(6.7%)??Staphylococcus aureus(5.9%) and Enterococcus faecium(5.9%) were the most common isolates??The rate of Extended-spectrum beta-lactamase (ESBLs) produced by Escherichia coli and Klebsiella pneumoniae were 54.5% and 42.9??,respectively. The isolation rates of the Methicillin resistant Staphylococcus aureus (MRSA) and Methicillin resistant Staphylococcus epidermidis(MRSE) were 39.2% and 79.4%,respectively. The resistant rates of Enterobacter to carbapenem antibacterial activity were very low, and the resistant of Acinetobacter baumannii was very serious. Vancomycin, Teicoplanin are the most effective antimicrobial agents against Gram-positive cocci, No vancomycin-resistant Staphylococcus aureus were found. Conclusion It should adopt a more positive effectively infection control measures to reduce the occurrence and spread of antibiotic resistant bacteria, appropriate initial antimicrobial therapy is of great significance to improve outcomes in patients with bloodstream infection.