In vitro antibacterial activity of sucralfate

The effect of sucralfate (12.5 mg/ml) on the growth ofEscherichia coli (ATCC 25922),Enterococcus faecalis (ATCC 29212) and two isolates ofPseudomonas aeruginosa (ATCC 27853 and a multi-resistant clinical isolate) was studied in vitro at pH values of 3.0, 4.5, 6.0 and 7.4. A bacteriostatic effect of sucralfate was demonstrated forPseudomonas aeruginosa at a pH of 6.0 and 7.4 and forEscherichia coli andEnterococcus faecalis at a pH of 6.0. The bacteriostatic effect was most pronounced at high pH values. Sucralfate had no bactericidal effect on the bacteria tested at the concentration used.     

In vitro antibacterial activity of Omani and African honey

The study aims to investigate the antibacterial activity of honey obtained from different parts of Oman and compare it with that of honey obtained from elsewhere in Africa. A total of 24 honey samples (16 from different parts of Oman and eight from elsewhere in Africa) were investigated for their antibacterial activity against Staphylococcus aureus (NCTC 6571), Escherichia coli (NCTC 10418) and Pseudomonas aeruginosa (NCTC 10662) using standard antimicrobial assays. Marked variations in the antibacterial activity of the different honey samples were observed. Fourteen of the 16 Omani samples and five of the eight African samples showed antibacterial activity ranked as either fair, good or excellent to at least one of the three bacterial strains tested. Both Omani and African honeys possess in vitro antibacterial activity against the three bacterial strains tested, with 25% of the samples showing excellent antibacterial activity.     

阳离子卟啉衍生物的体外光动力抗菌活性研究

目的 研究阳离子卟啉衍生物介导的光动力抗菌化学疗法(CPD-PACT)对体外培养的绿脓杆菌的抑制作用,为研究其高效的抗菌作用特点提供依据.方法 采用二倍稀释法考察培养条件对CPD最小抑菌浓度(MIC)的影响,扩散法测定CPD的抑菌圈,活菌计数法测定CPD的体外抗菌后效应,并通过激光扫描共聚焦显微镜(CLSM)观察绿脓杆菌的活力和形态变化.结果 细菌接种量对MIC值存在一定的影响;培养基pH值的升高会使化合物的MIC值相应升高;血清蛋白体积分数的增加会使光反应的MIC值升高,而暗反应的MIC值降低.抑菌圈的大小主要取决于激光能量密度的强弱,而受光敏剂浓度的影响较小.CPD对绿脓杆菌有较强的抑制和杀灭作用,且存在明显的抗菌后效应,但光疗结束后存活的细菌会继续增殖.CLSM观察结果表明,CPD-PACT可破坏细菌外膜完整性,使细菌内容物泄露,活力减弱,最终导致细菌死亡.结论 CPD-PACT对绿脓杆菌具有高效的抗菌活性和明显的抗菌后效应,适合作为新一代抗菌候选药物进行深度开发.     

In vitro antibacterial activity of piperacillin/quinolone combinations

Combinations of piperacillin (PIP) with 3 systemic fluoroquinolones: pefloxacin (PEF), ofloxacin (OFL) and ciprofloxacin (CIP) were evaluated by checkerboard technique (bacteriostatic activity) and by time-killing curve technique (bactericidal activity as a function of time) for 4 bacterial strains with following MICs (micrograms/ml): 1 E. coli (PIP: 1, PEF: 0.12, OFL: 0.06, CIP: 0.016); 1 S. marcescens (0.25, 0.06, 0.06, 0.016); 2 P. aeruginosa (2, 1, 0.5, 0.12 and 4, 2, 2, 0.25). Bacteriostatic activity of the 3 combinations showed only different or additive effects (index FIC: 0.62 to 1.5). If the bactericidal activity was defined as a less than or equal to 3 log 10 decrease in CFU/ml in 3-6 h and less than or equal to 4 log 10 in 6-24 h, PIP was not bactericidal at MIC x 8 for all strains; nevertheless, combinations of PIP 2 + PEF 0.25, OFL 0.12 or CIP 0.016 on E. coli and PIP 1 + PEF 0.25, OFL 0.25 or CIP 0.06 on S. marcescens showed bactericidal activity, superior to each antibiotic singly. For P. aeruginosa a less than or equal to 4 log 10 decrease in 6-24 h was observed only in combination with PIP 16 + PEF 1, OFL 1 or CIP 0.25 and PIP 32 + PEF 4, OFL 4 or CIP 0.5. Combinations of PIP with quinolones showed synergistic effects: bactericidal activity was more rapid and prolonged with such combinations at concentrations near MICs and obtained with usual therapeutic doses.     

In vitro antibacterial activity of antiseptics against vaginal lactobacilli

The results of investigations carried out to evaluate the inhibitory activity in vitro of seven vaginal antiseptic douche solutions against several strains of vaginal lactobacilli isolated from asymptomatic women are reported. Some of the products examined showed marked antibacterial activity even at high dilutions and for short exposure times. The post-antibiotic effect of two of these antiseptics on vaginal lactobacilli was also evaluated. The results of these investigations suggest that uncontrolled use of antiseptic products could cause changes in the normal vaginal flora.     

In vitro antibacterial activity of some plant essential oils

Background:  

To evaluate the antibacterial activity of 21 plant essential oils against six bacterial species.     

注射用头孢拉宗钠的体内外抗菌活性研究

目的评价注射用头孢拉宗钠的体内外抗菌活性。方法选取663株临床分离致病菌为实验菌,以头孢美唑、头孢西丁、头孢替坦、头孢米诺、头孢唑啉、头孢呋辛、头孢哌酮、头孢吡肟为对照药物,分别采用平皿二倍稀释法测定药物最低抑菌浓度（MIC）、最低杀菌浓度（MBC）、绘制杀菌曲线（KCs）并行诱导耐药实验,观察头孢拉宗的体外抗菌作用;建立小鼠腹腔感染模型,评价头孢拉宗皮下给药对金黄色葡萄球菌、大肠埃希菌、肺炎克雷伯杆菌感染小鼠的体内疗效。结果头孢拉宗对多种革兰阴性菌具有较高的抗菌活性,尤以对大肠埃希菌和肺炎克雷伯杆菌的抗菌活性更为突出,其MIC50、MIC90分别为0.5、8μg/ml,对产超广谱β-内酰胺酶大肠埃希菌和肺炎克雷伯杆菌的抗菌活性也较强,其MIC50、MIC90分别为4、8μg/ml;头孢拉宗对革兰阴性菌的抗菌作用大多优于头孢西丁、头孢美唑、头孢唑啉、头孢哌酮、头孢替坦和头孢呋辛,而对革兰阳性菌的抗菌活性较弱,与头孢替坦和头孢米诺相近。MBC和KCs测定结果表明,头孢拉宗对金黄色葡萄球菌、大肠埃希菌、肺炎克雷伯杆菌均具有杀菌作用。以1/4MIC剂量诱导20d后,头孢拉宗对金黄色葡萄球菌、大肠埃希菌和肺炎克雷伯杆菌的抗菌活性无明显改变。头孢拉宗皮下给药对大肠埃希菌ATCC25922、大肠埃希菌1515、肺炎克雷伯杆菌7、肺炎克雷伯杆菌9613感染小鼠的体内疗效明显优于头孢美唑和头孢唑啉（均P〈0.01）;对金黄色葡萄球菌感染小鼠的体内疗效与头孢美唑相近（P〉0.05）,但弱于头孢唑啉（P〈0.01）。结论注射用头孢拉宗钠对多数革兰阴性菌,特别是大肠埃希菌和肺炎克雷伯杆菌具有较强的体外抗菌活性;同时对大肠埃希菌、肺炎克雷伯杆菌、金黄色葡萄球菌腹腔感染小鼠的体内疗效也较好。     

In vitro antibacterial activity of cefmenoxime (SCE 1365)

617 clinical isolates were tested, 592 of which were from hospital source. The minimal inhibitory concentrations of cefmenoxime were determined by a microtiter dilution method, using Mueller-Hinton broth. The results obtained give a 92% agreement with the reference agar-dilution method. Cefmenoxime shows a potent activity against Enterobacteriaceae (n = 420): the modal MIC is less than or equal to 0,03 mg/l, and 90% of them are inhibited by 1 mg/l. Some isolates require a higher concentration, above 32 mg/l: Enterobacter (8%), indole-positive Proteus (13%), Serratia (3%), Citrobacter (3%). Pseudomonas (n = 71) and Acinetobacter (n = 62) appear to be less susceptible than Enterobacteriaceae. The modal MIC is 16 mg/l and the concentration inhibiting 90% of the isolates is above 32 mg/l. The modal MIC of cefmenoxime against Staphylococcus aureus (n = 64) is 1 mg/l, and 90% of the strains belonging to this species are inhibited by 32 mg/l.     

In vitro antibacterial activity of enoxacin (CI-919)

Antibacterial activity of enoxacin was evaluated against more than 3,700 clinical isolates using the agar-dilution method and an inoculum of 10(4)-10(5) cells per site. For comparison other antibiotics appropriate for each species were also included. For most enterobacteria and for Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa, the MIC90 of enoxacin was below 2 mg/l. Serratia marcescens was more resistant; the MIC90 being 4 mg/ml. Enoxacin also showed high activity against Campylobacter jejuni and Neisseria gonorrhoeae. Streptococci were comparatively resistant, 32 mg/l to 64 mg/l of the compound being required to inhibit 90% of strains.     

金黄色葡萄球菌重组蛋白AtlM的体外抗菌效应初步探讨

目的通过基因工程技术获取金黄色葡萄球菌（ ATCC25923）自溶素片段AtlM重组蛋白（ rAtlM）,初步探讨其体外抗菌效应。方法根据GenBank 中金黄色葡萄球菌atlM基因序列（ AC：D17366）设计合成特异引物,采用PCR技术扩增相应的序列并构建重组表达质粒pET-32а（＋）/atlM,经由IPTG诱导后通过等电点洗脱技术获取纯化的rAtlM;采用微量肉汤稀释法测定rAtlM对ATCC25923及其苯唑西林诱导耐药株的最低抑菌浓度（ minimal inhibitory concentration ,MIC）;体外试验测定rAtlM对ATCC25923菌株及其耐药株的抗菌活性。结果成功构建了原核表达载体pET-32а（＋）/atlM,表达的重组蛋白AtlM对ATCC25923标准株和耐药株的MIC分别为8μg/ml和64μg/ml。体外抑菌试验显示rAtlM作用于ATCC25923标准株和耐药株1 h后即对细菌生长具有抑制作用（ P值分别为0．004和0．026）,对标准株作用持续到5 h测定点（P＝0．012）,对苯唑西林耐药株作用持续到3 h测定点（P＝0．001）,5 h后与未加药物的对照组相比差异无统计学意义（P＝0．102）。结论50μg/ml的rAtlM对金黄色葡萄球菌（ ATCC25923）及苯唑西林耐药株初步显示出一定的抑菌作用,具有作为抗菌药物的可能性。     

青霉源抗菌肽类霉肽素的体外抑菌活性研究

目的 研究抗菌肽类霉肽素(AF)的体外抑菌活性.方法 通过抑菌圈法和二倍稀释法检测AF的抗菌谱和对金黄色葡萄球菌的MIC;通过检测在AF中传代菌的敏感性确定细菌是否容易对AF产生抗药菌;将AF和细菌在不同温度和pH环境作用后检测抑菌活性,明确AF发挥活性的最适温度和pH值.结果 AF对大部分供试细菌和抗药菌有效,对金黄色葡萄球菌的MIC为0.8 mg/ml,金黄色葡萄球菌在AF中传代200代后敏感性不变.在14℃到30℃之间AF的抑菌活性随温度升高而降低,在pH 3到pH 10之间AF的活性随pH值升高而降低.结论 AF是一种对抗性菌有效的广谱抗菌肽,而且不容易诱导细菌产生抗药性.     

青霉源抗菌肽类霉肽素的体外抑菌活性研究

目的研究抗菌肽类霉肽素（AF）的体外抑菌活性。方法通过抑菌圈法和二倍稀释法检测AF的抗菌谱和对金黄色葡萄球菌的MIC;通过检测在AF中传代菌的敏感性确定细菌是否容易对AF产生抗药菌;将AF和细菌在不同温度和pH环境作用后检测抑菌活性,明确AF发挥活性的最适温度和pH值。结果AF对大部分供试细菌和抗药菌有效,对金黄色葡萄球菌的MIC为0．8mg／ml,金黄色葡萄球菌在AF中传代200代后敏感性不变。在14℃到30℃之间AF的抑菌活性随温度升高而降低,在pH3到pH10之间AF的活性随pH值升高而降低。结论AF是一种对抗性菌有效的广谱抗菌肽,而且不容易诱导细菌产生抗药性。     

In vitro antibacterial activity of ceftizoxime on Pasteurella and EF4

The in vitro activity of ceftizoxime, a new third-generation cephalosporin, was tested by determining minimal inhibitory concentrations (MIC) by agar dilution method, for 150 strains of genus Pasteurella and group EF4 bacteria from various sources. All the strains were susceptible to ceftizoxime and inhibited by 0.03 micrograms/ml concentration. No significant difference appeared between the 7 species and human and animal strains. Group EF4 bacteria, frequently isolated from animal bite wounds in humans, had higher MIC (O.25-1 micrograms/ml). Results were compared to those obtained with cefotaxime, cephalothin, penicillin G and ampicillin.     

In vitro antibacterial activity of norfloxacin compared with eight other antimicrobial agents

The antibacterial activity of norfloxacin, an organic acid structurally related to nalidixic acid, was compared with that of the oral cephalosporins cefaclor and cephalexin, and with that of nalidixic acid, cinoxacin, amikacin, ampicillin, trimethoprim alone and the combination of trimethoprim and sulfamethoxazole. Agar dilution studies were performed with a total of 398 clinical isolates of gram-negative bacteria, Norfloxacin was found to be the most active drug studied against each of the different groups of organisms tested. MIC₉₀ values for norfloxacin were as follows:Citrobacter spp., 2μg/ml;Enterobacter spp., 0.13μg/ml;Escherichia coli, 0.06μg/ml;Klebsiella spp., 0.13μg/ml;Proteus spp., 0.06μg/ml;Salmonella spp., 1μg/ml;Serratia spp., 0.13μg/ml; andPseudomonas spp., 2μg/ml. MIC₉₀ values for the other drugs were 4μg/ml or greater and many organisms were totally resistant to one or more of the other drugs (MIC > 128μg/ml). Cross resistance between norfloxacin and the related drugs nalidixic acid and cinoxacin was not observed.     

含镁多孔支架材料的体外抗菌活性和生物相容性

文题释义：快速成型：是一种材料加工方法,它是在现代CAD/CAM技术、激光技术、计算机数控技术、精密伺服驱动技术及新材料技术的基础上集成发展起来的。不同种类的快速成型系统因所用成形材料不同,成形原理和系统特点也各有不同,但基本原理都是“分层制造,逐层叠加”。 聚乳酸：是以乳酸为主要原料聚合得到的聚合物,具有良好的生物降解性、生物相容性以及延展性,但其机械强度不足,且降解后会产生酸性代谢产物,限制了其应用范围,常与其他一种或多种生物材料复合使用,以增强骨生物活性或生物力学强度。 背景：将多聚物材料与生物陶瓷材料复合制成有机/无机复合三维支架材料,可赋予支架骨传导所必需的理化特性,同时强化材料的力学性能,但大多数骨替代材料无法预防缺损部位的感染。研究发现由于镁的降解可产生局部碱性环境,使镁具有一定的抗菌活性。 目的：探讨含镁多孔支架材料的体外抗菌活性和细胞相容性。 方法：应用低温快速成型技术制备聚乳酸/β-磷酸三钙/镁多孔支架材料,其中β-磷酸三钙与镁的质量比分别为2∶1和1∶2,分别设为PTM(2∶1)组、PTM(1∶2)组;同时应用低温快速成型技术制备聚乳酸与聚乳酸/β-磷酸三钙多孔支架材料,分别设为P组、PT组。检测4组支架的表面形貌、孔径、孔隙率及压缩模量。将金黄色葡萄球菌(ATCC 35923)接种于4组支架表面24 h,通过涂板计数法和激光共聚焦显微镜观察材料的抗菌活性。将小鼠前成骨细胞MC3T3-E1分别与4组支架材料共培养,通过CCK-8法分析材料对细胞黏附和增殖的影响。 结果与结论：①4组支架材料表面都形成相对均匀的多孔结构,4组支架间孔径大小和孔隙率比较差异均无显著性意义(P > 0.05);②PTM(2∶1)组和PTM(1∶2)组压缩模量明显高于P组、PT组(P < 0.05),PTM(1∶2)组明显高于PTM(2∶1)组(P < 0.05);③涂板计数实验显示,PTM(2∶1)组、PTM(1∶2)组菌落形成单位明显低于P组、PT组(P < 0.05),其余组间比较差异无显著性意义(P > 0.05);④培养6 h,PT组、PTM(2∶1)组、PTM(1∶2)组黏附细胞数量多于P组(P < 0.05),PTM(2∶1)组和PTM(1∶2)组比较差异均无显著性意义(P > 0.05);⑤培养1 d时,仅PT组细胞增殖优于P组(P < 0.05);培养4,7 d时,PT组、PTM(2∶1)组、PTM(1∶2)组细胞增殖均优于P组(P < 0.05),PTM(2∶1)组和PTM(1∶2)组比较差异均无显著性意义(P > 0.05);⑥结果表明,聚乳酸/β-磷酸三钙/镁多孔支架材料不但具有良好的抗菌活性,而且具有优良的细胞相容性和一定的抗压能力。 ORCID: 0000-0002-3367-674X(马瑞) 中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

Stimulation of hemopoietic colony formation from mouse marrow cells in vitro using human dialyzable leukocyte extracts-immodin-sevac

The influence of dialyzable extract from human leukocytes (DLE) on the in vitro growth of the granulocyte-macrophage colony-forming cell (GM-CFC) colonies from progenitors of mouse bone marrow cells was studied. DLE alone did not induce the colony growth but it modulated the number of colonies if administered together with a colony-stimulating factor (CSF).The costimulatory effect prevailed in a broad range of DLE dilution and the index of increase was enhanced with the lowering of the CSF concentration. The costimulatory augmentation of clonal proliferation of GM-CFC with DLE was further strengthened by addition of indomethacin, thus indicating an intervening role of prostaglandins in the modulatory influence of DLE.     

Effects of long-term treatment of mice with anti-I-J monoclonal antibody and dialyzable leukocyte extract on immune function and lifespan

In 1969 Walford hypothesized that age-related dysfunctions of the immune system may be involved in the pathogenesis of the lesions and disease of aging. Studies were initiated to test whether immunologic interventions intended to maintain the integrity of the immune system would delay the onset of diseases of aging and prolong lifespan. Adult BC3F1 mice were treated with anti-I-J monoclonal antibody, with human dialyzable leukocyte extract, or with saline once a week for one year. Spleen cells from the mice were then assayed for suppressor, T-helper and B-cell activity. Treatment with dialyzable leukocyte extract decreased the elevated nonspecific suppressor activity. Mice treated with anti-I-J antibody had elevated T-helper cell activity. In another experiment, mice were treated weekly with anti-I-J antibody, dialyzable leukocyte extract, or saline from 18 months of age until natural death. The mice were immunized with avian gammaglobulin at 27 and again at 29 months of age. Both types of immunologic intervention resulted in a greater secondary antibody response than that of the saline-treated control mice. Mice treated with anti-I-J antibody survived longer than did mice of the other two groups. There was a correlation between the magnitude of the secondary response of individual mice and their lifespan. The results provide support for the immunologic theory of aging.     

In vitro antibacterial activity and beta-lactamase stability of the new carbapenem SM-7338

The in vitro activity of the new carbapenem SM-7338 was tested in comparison with imipenem, ceftazidime, cefotaxime, flomoxef, cefuzonam and cefmetazole against 2850 clinical bacterial isolates. SM-7338 showed good activity against a broad spectrum of grampositive and gram-negative bacteria. SM-7338 was very active against gram-negative bacteria, inhibiting allEnterobacteriaceae, except 25 % ofSerratia marcescens isolates, at a concentration of 0.78 mg/l. SM-7338 inhibited the majority ofPseudomonas spp. at concentrations of 3.13 mg/l, its activity being twofold higher than that of imipenem. However, the activity of SM-7338 against gram-positive cocci was about one-fourth that of imipenem. Against anaerobes, SM-7338 also had the best activity of the -lactams tested. The compound was inactive against methicillin-resistant staphylococci,Enterococcus faecium, Xanthomonas maltophilia andFlavobacterium spp., as were the other -lactams. SM-7338 was quite stable in the presence of various types of -lactamase, but was hydrolyzed byXanthomonas maltophilia -lactamase, as was imipenem. This high degree of stability was responsible for the potent activity of SM-7388 against -lactamase-producing species such asEnterobacter cloacae, Citrobacter freundii andProteus vulgaris. SM-7338 also showed bactericidal activity against clinical isolates at the MIC or at concentrations slightly above the MIC.