加替沙星对金黄色葡萄球菌的体外抗菌活性

考察加替沙星对金黄色葡萄球菌的体外抗菌活性以及抗MRSA的能力。采用药敏纸片法（K－B法），从129株临床分离的金黄色葡萄球菌筛选对甲氧西林和氟喹诺酮类药物的耐药菌株，用琼脂二倍稀释法对交叉耐药菌进行MIC测试，比较了加替沙星与环丙沙星等第二代氟喹诺酮类药物的耐药菌株，用琼脂二倍稀释法对交叉耐药菌进行MIC测试，比较了加替沙星与环丙沙星等第二代氟喹诺酮类药物的抗菌活性。用苯唑西林筛选三代自发突变株，比较环丙沙星、加替沙星对MRSA的抗菌活性。实验表明，苯唑西林、环丙沙星、氧氟沙星、左氧氟沙星对129株金黄色葡萄球菌的耐药率相似。体外活性表明，加替沙星比环丙沙星等第二代氟喹诺酮类药物的抗菌活性强，抗MRSA菌株的活性较强；敏感金黄色葡萄球菌发生加替沙星耐药的突变频率在所试药物中也是最低的。说明加替沙星比环丙沙星等第二代氟喹诺酮类药物的抗菌活性得到明显提高。     

3种氟喹诺酮类药物的体外抗生素后效应研究

目的研究3种氟喹诺酮类药物对铜绿假单胞菌、金黄色葡萄球菌、大肠埃希氏菌的体外抗生素后效应（PAE）,为临床优化氟喹诺酮类药物给药方案提供参考依据。方法采用微量稀释法测定左氧氟沙星（LVFX）、司帕沙星（SPLX）和环丙沙星（CPLX）等3种氟喹诺酮类药物的最低抑菌浓度（MIC）和体外PAE。结果LVFX对铜绿假单胞菌的PAE最长,对金黄色葡萄球菌的PAE最短;SPLX对大肠埃希氏菌的PAE最长,对铜绿假单胞菌的PAE最短;CPLX对大肠埃希氏菌的PAE最长,对金黄色葡萄球菌的PAE最短;三种氟喹诺酮药物对试验菌株均呈现浓度依赖性。结论临床使用氟喹诺酮类药物时应重视其抗生素后效应。     

莫西沙星与其他12种抗菌药物对呼吸道常见感染致病菌体外抗菌活性研究

目的比较研究莫西沙星与其他12种抗菌药物对临床常见致病菌的体外抗菌活性.方法采用琼脂平板二倍稀释法测定对411株临床分离菌株的最低抑菌浓度.结果金黄色葡萄球菌(包括MRSA)和肺炎链球菌(包括PISP和PRSP)对万古霉素的敏感性最高,敏感率为95.8%～100%,对莫西沙星、加替沙星的敏感性较高,对大环内酯类药物则比较耐药.流感嗜血杆菌、卡他莫拉菌对莫西沙星、加替沙星等4种氟喹诺酮类和5种头孢菌素类及阿齐霉素比较敏感.肺炎克雷伯菌(包括产ESBLs菌株)对莫西沙星等4种氟喹诺酮类和头孢美唑很敏感;非产ESBLs菌株对8种抗菌药物均敏感,但产ES-BLs菌株对第二、三代头孢菌素则显示了较高的耐药率.大肠埃希菌(包括产ESBLs菌株)对氟喹诺酮类敏感率在40%左右,非产ESBLs菌株对5种头孢菌素均较敏感,但产ESBLs菌株除对头孢美唑敏感外,对其他头孢菌素类耐药率较高;结论莫西沙星与其他12种抗菌药物比较,对革兰阳性菌(包括MRSA和PRSP)作用增强,对肺炎克雷伯菌(包括产ESBLs菌株)抗菌活性较强,大肠埃希菌对莫西沙星与其他氟喹诺酮类有一定的交叉耐药性.     

比较6种氟喹诺酮类药物对金黄色葡萄球菌的防耐药变异浓度

目的比较6种氟喹诺酮类药物对临床分离金黄色葡萄球菌耐药突变体的选择能力。方法用呼吸道标本,选择对苯唑西林、环丙沙星敏感的金黄色葡萄球菌36株,采用标准琼脂二倍稀释法、标准琼脂平板稀释法,测定6种氟喹诺酮类药物对金黄色葡萄球菌的MIC、MPC。结果 MPC值比较,莫西沙星最低;而环丙沙星最高。选择指数(MPC90/MIC90)较低有如下4种:莫西沙星、卡屈沙星、加替沙星和帕珠沙星,均为2。6种药物MPC90值与其体内药动学参数比较,莫西沙星和卡屈沙星小于其Cmax。结论莫西沙星、卡屈沙星和加替沙星对金葡菌的MPC值较低,突变选择窗范围相对较窄。     

革兰阴性杆菌对四种氟喹诺酮药物体外耐药监测

目的了解革兰阴性杆菌(G-)对环丙沙星,左氧氟沙星,氧氟沙星,罗美沙星体外抗菌活性,为临床用药提供依据。方法采用K-B纸片法,对分离出的256株菌株进行耐药性监测,并用标准菌株进行监控,以NCCLS标准进行结果判读。结果大肠埃希菌对4种氟喹诺酮类药物有55%以上的耐药率。除铜绿假单胞菌外革兰阴性杆菌对左氧氟沙星的耐药率均低于其他3种药物,克雷伯菌、铜绿假单胞菌、不动杆菌对环丙沙星耐药率在30.76%～33.33%。结论G-杆菌对氟喹诺酮类药物有交叉耐药现象,医生应不断参考本地区细菌耐药变化,最大限度发挥氟喹诺酮药物的作用。     

6种氟喹诺酮类药物对凝固酶阴性葡萄球菌的防耐药变异浓度分析

目的 比较6种氟喹诺酮类药物对临床分离凝固酶阴性葡萄球菌耐药突变体的选择能力.方法 选择呼吸道标本,对苯唑西林、环丙沙星敏感的凝固酶阴性葡萄球菌34株,采用标准琼脂二倍稀释法、标准琼脂平板稀释法,测定6种氟喹诺酮类药物对凝固酶阴性葡萄球菌的最低抑菌浓度(MIC)、防耐药变异浓度(MPC).结果 MPC值比较,莫西沙星最低(MPC90为1 mg/L),左氧氟沙星和环丙沙星最高(MPC90均为32 mg/L).莫西沙星、卡屈沙星和加替沙星的MPC90/MIC90较低,均为2.结论 莫西沙星、卡屈沙星和加替沙星对凝固酶阴性葡萄球菌的MPC值较低,突变选择窗范围相对较窄.     

甲磺酸帕珠沙星治疗急性盆腔感染的疗效观察

甲磺酸帕珠沙星(Pazufloxacin mesilate)是日本富山化学工业株式会社研究开发的新一代氟喹诺酮类抗菌药,于2002年4月在日本首次上市,该药在化学结构上做了重要的改变,将C10上传统的C-N键改变成C-C键,具有抗菌谱广,抗菌活性高,不仅对肠杆菌属、克雷伯菌、变形杆菌属、嗜血杆菌属、沙门菌属、志贺菌属、不动杆菌属及假单胞菌属等革兰阴性菌具有良好的体外抗菌活性,对葡萄球菌属、溶血性链球菌、肠球菌等革兰阳性菌的抗菌活性较其他喹诺酮类药物明显增强,尤其是对厌氧菌、支原体有较强的抗菌活性[1,2],且抗生素后效应时间长。我们用甲磺酸帕…     

氟喹诺酮类药物体外诱导大肠埃希菌交叉耐药性研究

目的探讨大肠埃希菌在体外对氟喹诺酮类药物的交叉耐药性。方法：采用多步诱导法,对大肠埃希菌临床分离株分别进行环丙沙星、左氧氟沙星、加替沙星的诱导耐药试验;用琼脂稀释法测定药物敏感性。结果：大肠埃希菌经环丙沙星诱导后其MIC90由0．0548μg／ml升到252．5108μg／ml：对左氧氟沙星和加替沙星产生交叉耐药,MIC90由3．3873μg／ml和3．2494μg／ml升到50．2169μg／ml和25．1102μg／ml。经左氧氟沙星诱导后其MIC90由3．3873μg／ml升到390．7599μg／ml;对环丙沙星和加替沙星产生交叉耐药,MIC90分别由0．0548μg／ml和3．2494μg／ml升到390．7599μg／ml和59．7173μg／ml。经加替沙星诱导后其MIC90由3．2494μg／ml升到362．0762μg／ml;对环丙沙星和左氧氟沙星产生交叉耐药,MIC90分别由0．0548μg／ml和3．3873μg／ml升到415．8149μg／ml和362．0762μg／ml。3种氟喹诺酮类药物诱导前后大肠埃希菌ESBLs阳性率无变化。临床分离大肠埃希菌ESBLs阳性菌株对3种氟喹诺酮类药物的耐药率分别为82．8％、72．4％、51．7％均大于ESBLs阴性菌株的60．7％、28．6％、17．9％。     

莫西沙星与其他12种抗菌药物对呼吸道常见感染致病菌体外抗菌活性研究

目的:比较研究莫西沙星与其他12种抗菌药物对临床常见致病菌的体外抗菌活性.方法:采用琼脂平板二倍稀释法测定对411株临床分离菌株的最低抑菌浓度.结果:金黄色葡萄球菌(包括MRSA)和肺炎链球菌(包括PISP和PRSP)对万古霉素的敏感性最高,敏感率为95.8%～100%,对莫西沙星、加替沙星的敏感性较高,对大环内酯类药物则比较耐药.流感嗜血杆菌、卡他莫拉菌对莫西沙星、加替沙星等4种氟喹诺酮类和5种头孢菌素类及阿齐霉素比较敏感.肺炎克雷伯菌(包括产ESBLs菌株)对莫西沙星等4种氟喹诺酮类和头孢美唑很敏感;非产ESBLs菌株对8种抗菌药物均敏感,但产ES-BLs菌株对第二、三代头孢菌素则显示了较高的耐药率.大肠埃希菌(包括产ESBLs菌株)对氟喹诺酮类敏感率在40%左右,非产ESBLs菌株对5种头孢菌素均较敏感,但产ESBLs菌株除对头孢美唑敏感外,对其他头孢菌素类耐药率较高;结论:莫西沙星与其他12种抗菌药物比较,对革兰阳性菌(包括MRSA和PRSP)作用增强,对肺炎克雷伯菌(包括产ESBLs菌株)抗菌活性较强,大肠埃希菌对莫西沙星与其他氟喹诺酮类有一定的交叉耐药性.     

安妥沙星纸片扩散法外抗菌活性测定折点初步研究

目的：确定安妥沙星对葡萄球菌属、肠杆菌科、非发酵菌及嗜血杆菌属的纸片扩散法体外抗菌活性测定折点。方法：采用标准琼脂二倍稀释法与纸片扩散法（5μg和10μg）测定安妥沙星对临床常见致病菌的敏感性,并与临床常用的氟喹诺酮类药物相比较分析,结合人体药代动力学参数,利用MIC与抑菌圈直径散点图,初步确定安妥沙星纸片扩散法对常见细菌的折点。结果：安妥沙星的体外抗菌作用与左氧氟沙星接近且相关性最好,根据安妥沙星琼脂稀释法体外抗菌活性测定的临界浓度（嗜血杆菌敏感临界浓度为≤1mg／L,其他细菌敏感、中介与耐药临界浓度分别为≤2、4、≥8mg／L）,利用MIC与抑菌圈直径散点图初步确定安妥沙星（10扯g）纸片对嗜血杆菌抑菌圈直径≥21mm为敏感,其它菌种耐药、中介与敏感的抑菌圈直径分别为≤14mm、15～17mm和≥18mm。标准菌株质控范围分别为大肠埃希菌ATCC2592224～31mm,铜绿假单胞菌ATCC2785322～26mm,金黄色葡萄球菌ATCC2592322～28mm。结论：通过体外抗菌活性比较,利用MIC与抑菌圈直径散点图,初步确定了安妥沙星纸片扩散法体外抗菌活性测定对常见细菌的折点,供临床应用参考与验证。     

Comparative activities of six different fluoroquinolones against 9,682 clinical bacterial isolates from 20 European university hospitals participating in the European SENTRY surveillance programme

The in-vitro activities of gatifloxacin, trovafloxacin, levofloxacin, sparfloxacin, ofloxacin, and ciprofloxacin were tested against 9,682 clinical bacterial isolates from 20 European university hospitals participating in the European SENTRY surveillance programme. Gatifloxacin and trovafloxacin exhibited the highest activities against Gram-positive cocci, while levofloxacin, ofloxacin, ciprofloxacin, and gatifloxacin were the most active against Enterobacteriaceae. Ciprofloxacin and levofloxacin showed the highest antimicrobial activities against Pseudomonas spp., while gatifloxacin and trovafloxacin were the most active against Acinetobacter spp. and Stenotrophomonas maltophilia. All Haemophilus spp. and Moraxella catarrhalis isolates were fully susceptible to all quinolones tested. Overall, the new quinolones, showed improved activity against Gram-positive cocci and Gram-negative non-fermenters while retaining their broad-spectrum activity against Gram-negative bacilli.     

国产甲磺酸左氧氟沙星体外抗菌活性研究

测定国产甲磺酸左氧氟沙星体外抗菌活性,并与进口左氧氟沙星作比较,以临床常用的氧氟沙星和环丙沙星为对照。结果表明,国产甲磺酸左氧氟沙星与进口左氧氟沙星体外抗菌活性无差异。甲磺酸左氧氟沙星抗菌谱广抗菌活性强,对革兰氏阴性肠道杆菌、肺炎克雷伯氏菌、肠杆菌属细菌、变形杆菌及嗜血杆菌和不动杆菌ＭＩＣ５０值是氧氟沙星的１／２,与环丙沙星一致,分别为＜０．０３、＜０．０３、＜０．０３、０．１２５和０．０３ｍｇ／Ｌ;它对大肠埃希氏菌、金葡球菌、肺炎链球菌、肠球菌、厌氧菌的ＭＩＣ５０值是氧氟沙星和环丙沙星的１／２～１／４;对铜绿假单胞菌ＭＩＣ５０为１ｍｇ／Ｌ,是氧氟沙星的１／２,但稍高于环丙沙星。该产品体外抗菌活性受细菌接种量、血清含量和ｐＨ值影响不明显。研究还表明该产品为一杀菌剂,对临床常见致病菌如大肠埃希氏菌、肺炎克雷伯氏菌、变形杆菌、铜绿假单胞菌、不动杆菌、葡萄球菌、肠球菌、肺炎链球菌、厌氧菌均有良好的杀菌作用。     

In vitro susceptibilities of Bartonella and Rickettsia spp. to fluoroquinolone antibiotics as determined by immunofluorescent antibody analysis of infected Vero cell monolayers.

The in vitro susceptibilities of Bartonella and Rickettsia spp. to different concentrations of ciprofloxacin, levofloxacin, ofloxacin and sparfloxacin in Vero cell cultures, were determined by enumeration of immunofluorescent-stained bacilli. After incubation in a CO(2)-enriched atmosphere, inocula were replaced and tested with media containing 12 different concentrations of each antibiotic in replicate for each species and the monolayers were re-incubated. Growth status was determined by evaluation of immunofluorescent staining bacilli. Effective inhibitory antibiotic dilution endpoints were determined by counting Bartonella- and Rickettsia-specific fluorescent foci across a range of antibiotic dilutions with an epi-fluorescent microscope, and were compared with an antibiotic-negative control. Based upon the use of C(max):MIC and AUC:MIC data, levofloxacin exhibited activity against Bartonella elizabethae and B. quintana.     

Inhibitory and bactericidal activities of gemifloxacin and other antimicrobials against Mycoplasma pneumoniae

The MIC of gemifloxacin was compared with that of sparfloxacin, levofloxacin, moxifloxacin, gatifloxacin, ciprofloxacin, doxycycline, erythromycin, azithromycin and clarithromycin using 97 clinical isolates of Mycoplasma pneumoniae. MBCs of fluoroquinolones were determined for a subgroup of 12 isolates. Macrolides were the most potent agents with MIC₉₀s for all drugs 0.001 mg/l. The doxycycline MIC₉₀ was 0.5 mg/l. Gemifloxacin MICs ranged from 0.001 to 0.25 mg/l. The gemifloxacin MIC₉₀ (0.125 mg/l) was equivalent to moxifloxacin and gatifloxacin, was 2-fold lower than sparfloxacin, 8-fold lower than levofloxacin and 32-fold lower than ciprofloxacin. MBCs for gemifloxacin were predominantly within 2–4 times the corresponding MIC values, indicating a bactericidal effect.     

司帕沙星与其他5种抗菌药体外抗菌活性比较研究

测定了司帕沙星对临床分离的１９９ 株致病菌的体外抗菌活性并与氧氟沙星、环丙沙星、头孢唑啉、头孢噻肟、阿米卡星的抗菌活性进行比较。司帕沙星对革兰阳性菌的ＭＩＣ９０为０．１２５～０．５ｍ ｇ／Ｌ,对金葡球菌、化脓链球菌的抑菌率均为１００％ ,强于氧氟沙星、环丙沙星;对革兰阴性菌也具有良好的体外抗菌活性,与氧氟沙星、环丙沙星相似。不同细菌接种量和不同浓度血清对其抗菌活性无明显影响,仅在ｐＨ５．０ 时抗菌活性略有下降     

六种氟喹诺酮对肠球菌的体外抗菌活性及利血平的影响

目的：研究氟喹诺酮类抗菌药物对临床分离肠球菌的体外抗菌活性,以及多重耐药泵抑制剂利血平对抗菌活性的影响.方法：收集临床分离的101株肠球菌（66株粪肠球菌和35株屎肠球菌）,用琼脂稀释法测定应用利血平前后6种氟喹诺酮对菌株的最低抑菌浓度（MIC）.结果：诺氟沙星、环丙沙星、氧氟沙星、左氧氟沙星、加替沙星、莫西沙星对66株粪肠球菌的MIC90依次为256、64、64、16、16、8 mg/L,对35株屎肠球菌的MIC90依次为＞512、512、128、128、32、32 mg/L.应用利血平之后,上述6种药物对粪肠球菌抗菌活性提高（MIC下降2倍或2倍以上）的株数依次为66（100%）、54（81.8%）、4（6.1%）、4（6.1%）、32（48.5%）和3（4.5%）株,对屎肠球菌抗菌活性提高的株数依次为35（100%）、29（82.9%）、1（2.9%）、0（0%）、6（20.7%）和2（5.7%）株.结论：新氟喹诺酮加替沙星、莫西沙星增强了对肠球菌的抗菌活性,利血平能够提高全部或部分被检测肠球菌对诺氟沙星、环丙沙星和加替沙星的敏感性,但仅使少数被检测肠球菌对氧氟沙星、左氧氟沙星和莫西沙星的敏感性提高.     

A critical review of the fluoroquinolones: focus on respiratory infections.

The new fluoroquinolones (clinafloxacin, gatifloxacin, gemifloxacin, grepafloxacin, levofloxacin, moxifloxacin, sitafloxacin, sparfloxacin and trovafloxacin) offer excellent activity against Gram-negative bacilli and improved Gram-positive activity (e.g. against Streptococcus pneumoniae and Staphylococcus aureus) over ciprofloxacin. Ciprofloxacin still maintains the best in vitro activity against Pseudomonas aeruginosa. Clinafloxacin, gatifloxacin, moxifloxacin, sitafloxacin, sparfloxacin and trovafloxacin display improved activity against anaerobes (e.g. Bacteroides fragilis) versus ciprofloxacin. All of the new fluoroquinolones display excellent bioavailability and have longer serum half-lives than ciprofloxacin allowing for once daily dose administration. Clinical trials comparing the new fluoroquinolones to each other or to standard therapy have demonstrated good efficacy in a variety of community-acquired respiratory infections (e.g. pneumonia, acute exacerbations of chronic bronchitis and acute sinusitis). Limited data suggest that the new fluoroquinolones as a class may lead to better outcomes in community-acquired pneumonia and acute exacerbations of chronic bronchitis versus comparators. Several of these agents have either been withdrawn from the market, had their use severely restricted because of adverse effects (clinafloxacin because of phototoxicity and hypoglycaemia; grepafloxacin because of prolongation of the QTc and resultant torsades de pointes; sparfloxacin because of phototoxicity; and trovafloxacin because of hepatotoxicity), or were discontinued during developmental phases. The remaining fluoroquinolones such as gatifloxacin, gemifloxacin, levofloxacin and moxifloxacin have adverse effect profiles similar to ciprofloxacin. Extensive post-marketing safety surveillance data (as are available with ciprofloxacin and levofloxacin) are required for all new fluoroquinolones before safety can be definitively established. Drug interactions are limited; however, all fluoroquinolones interact with metal ion containing drugs (eg. antacids). The new fluoroquinolones (gatifloxacin, gemifloxacin, levofloxacin and moxifloxacin) offer several advantages over ciprofloxacin and are emerging as important therapeutic agents in the treatment of community-acquired respiratory infections. Their broad spectrum of activity which includes respiratory pathogens such as penicillin and macrolide resistant S. pneumoniae, favourable pharmacokinetic parameters, good bacteriological and clinical efficacy will lead to growing use of these agents in the treatment of community-acquired pneumonia, acute exacerbations of chronic bronchitis and acute sinusitis. These agents may result in cost savings especially in situations where, because of their potent broad-spectrum activity and excellent bioavailability, they may be used orally in place of intravenous antibacterials. Prudent use of the new fluoroquinolones will be required to minimise the development of resistance to these agents.     

The bactericidal activity of levofloxacin against ampicillin-resistant and ampicillin-susceptible Haemophilus influenzae in comparison with ofloxacin, ciprofloxacin and sparfloxacin

The bactericidal activity of levofloxacin against four Haemophilus influenzae clinical isolates (two ampicillin-resistant and two susceptible) was compared with that of ofloxacin, ciprofloxacin and sparfloxacin at concentrations simulating the peak serum concentrations obtained with the recommended oral doses. Bactericidal activity was assessed using time-kill curves and minimum kill-time values. Both concentrations of levofloxacin rapidly killed all the study strains, with mean kill times of 4 h and no viable bacteria remaining after 18-h exposure. The bactericidal activities of levofloxacin, ofloxacin and sparfloxacin were similar. The minimum kill-times for both concentrations of ciprofloxacin were 28-35% longer than those of levofloxacin. These results support the use of levofloxacin for H. influenzae infections, including ampicillin-resistant strains.     

In vitro susceptibility of 4903 bacterial isolates to gemifloxacin--an advanced fluoroquinolone

The in vitro activity of gemifloxacin against over 4900 bacterial isolates was determined by microbroth dilution with interpretation in accordance with NCCLS guidelines. Susceptibility results were compared with those for ciprofloxacin, gatifloxacin, levofloxacin and moxifloxacin. Gemifloxacin and the other fluoroquinolones were not affected by either beta-lactamase production or penicillin-resistance in Streptococcus pneumoniae. The MIC90 values for gemifloxacin were: S. pneumoniae 0.063 mg/l; Haemophilus influenzae 0.016 mg/l; Moraxella catarrhalis 0.008 mg/l, methicillin-susceptible Staphylococcus aureus 0.063 mg/l; methicillin-susceptible Streptococcus pyogenes 0.031 mg/l; Enterobacteriaceae 0.031-0.16 mg/l; Pseudomonas aeruginosa 4 mg/l; Neisseria meningitidis 0.008 mg/l. The MIC90 for gemifloxacin was lower than those for the other quinolones tested against S. pneumoniae (ciprofloxacin 2-4 mg/l, gatifloxacin 0.5 mg/l, levofloxacin 1-2 mg/l, moxifloxacin 0.25 mg/l). This study confirms the enhanced potent activity of gemifloxacin against Gram-positive pathogens, its broad-spectrum, Gram-negative activity and indicates that gemifloxacin is likely to have an important role in treating patients with Gram-positive and/or Gram-negative infections.