三种大环内酯类药物对金葡菌和粪肠球菌的抗生素后效应

 目的：研究测定了红霉素、罗红霉素、阿齐霉素对两种常见致病菌金葡菌和粪肠球菌的抗生素后效应（PAE）。方法：应用分光光度测定法，通过实验组、对照组吸光度的变化来确定PAE。结果：3种大环内酯类抗生素各浓度组均呈现明显的PAE，对金葡菌的PAE要长于粪肠球菌。随着药物浓度的增加，PAE明显延长。特别是罗红霉素、阿齐霉素对金葡菌，红霉素、阿齐霉素对粪肠球菌，其PAE与药物浓度呈显著相关性（相关系数均大于0．92）。在亚MIC时，3种药物也都产生较长的PAE。结论：3种抗菌药物对金葡菌与粪肠球菌可产生显著的PAE效应，为新大环内酯类药物减少临床给药次数，延长给药间隔提供了药效学依据。     

三金胶囊抗菌作用的实验研究

目的：观察三金胶囊的抑菌作用。方法：应用金葡球菌、绿脓杆菌、大肠杆菌、甲型链球菌体内感染小鼠，观察三金胶囊灌胃给药后对染菌小鼠的保护作用，测定对金葡球菌等10种菌株最低抑菌浓度；观察药后大鼠尿液的抑菌作用。结果：三金胶囊对体内感染金葡菌、甲型链球菌等小鼠有保护作用，体外对金葡菌等9种细菌有明显抑菌作用，灌胃后尿液则试具有抑菌作用。结论：三金胶囊是治疗泌尿系炎症的有效药物。     

淋球菌对大环内酯类抗生素耐药探讨

目的：探讨淋病奈瑟菌对大环内酯类抗生素耐药情况。方法：对培养分离出淋病奈瑟菌547株进行红霉素、罗红霉素、交沙霉素、克拉霉素及阿奇霉素等大环内酯类抗生素敏感性检测。结果：547株淋球菌对交沙霉素、红霉素、罗红霉素、克拉霉素及阿奇霉素的耐药率分别为35．14％、22．17％、4．01％、19．47％和3．87％。在对交沙霉素耐药的192株淋球菌株中,有49株对红霉素呈交叉耐药,31株同时对红霉素、罗红霉素呈交叉耐药。结论：淋病奈瑟菌对大环内酯类抗生素耐药情况较严重,有交叉耐药,需医师在治疗淋病据药敏结果选敏感药,提高疗效,减少耐药株产生。     

磷霉素体外抗生素后效应的研究

磷霉素（ｆｏｓｆｏｍｙｃｉｎ，ＦＯＭ）自１９６９年合成以来，以其高效低毒、抗菌谱广、分布广泛和吸收快而逐渐受到临床医生的欢迎。我们采用Ａｖａｎｔａｇｅ微生物分析仪的吸光度法，研究了ＦＯＭ对４种２６株常见致病菌（金葡菌、粪肠球菌、绿脓假单胞菌和大肠埃希...     

大环内酯类抗生素的心脏毒性及防治

大环内酯类(Marcrolides)是由链霉菌产生的一类弱碱性抗生素,主要作用于细菌细胞核糖体50S亚单位,阻碍细菌蛋白质的合成,对军团菌、螺旋体、衣原体、立克次体等微生物有良好效果。对G^ 菌和某些阴性菌有较强的抗菌活性。此类抗生素主要有红霉素、麦迪霉素、螺旋霉素、交沙霉素等,近年来又相继开发了罗红霉素、克拉霉素．阿齐霉素、地红霉素等新的衍生物。它们拓展了红霉素的抗菌谱,增强了胞内杀菌能力和对酸的稳定性,易被肠道吸收。延长了药物半衰期,有良好的抗菌素后效应和免疫调节功能,因而临床应用十分广泛。其不良反应主要有胃肠道反应、肝损害、局部刺激等,近年来陆续报道了红霉素等药物的心脏毒性。由于心脏毒性来势凶险,严重者可致死。为安全、合理、有效用药。本文就大环内酯类抗生素的心脏素性作一简述,以供临床参考。     

水飞蓟宾及其同分异构体的抑菌谱及其与抗生素联合抑菌效应探讨

目的探讨水飞蓟宾及同分异构体的体外抗菌谱及水飞蓟宾与临床常用抗生素的联合抑菌效应。方法用微量肉汤稀释法测定水飞蓟宾及同分异构体对临床感染常见细菌的6种标准菌株和6种临床分离菌株(74株)的最低抑菌浓度(MIC)。用平板菌落计数法测定不同质量浓度水飞蓟宾对6种标准菌株的生长抑制曲线。用棋盘微量肉汤稀释法进行水飞蓟宾与临床常用抗生素的联合药敏试验,计算联合抑菌指数(FIC),判定水飞蓟宾与抗生素的联合抑菌效应。结果水飞蓟宾对表皮葡萄球菌、金黄色葡萄球菌、粪肠球菌和屎肠球菌标准菌株的MIC为50~400μg/m L,对大肠埃希菌和铜绿假单胞菌标准菌株的MIC均400μg/m L;对表皮葡萄葡萄球菌临床分离菌株的MIC分别为100、200、400、400μg/m L,对金黄色葡萄球菌、粪肠球菌和屎肠球菌临床分离菌株的MIC分别为400、400μg/m L;对大肠埃希菌和铜绿假单胞菌临床分离菌株的MIC均400μg/m L。水飞蓟宾其他同分异构体对6种标准菌株的MIC为≥400μg/m L。水飞蓟宾对表皮葡萄球菌、金黄色葡萄球菌、粪肠球菌和屎肠球菌标准菌株的生长曲线都有明显抑制作用,抑制效果随药物质量浓度增加而增加,对大肠埃希菌和铜绿假单胞菌标准菌株的生长曲线无影响。水飞蓟宾与青霉素/红霉素联用对革兰阳性试验菌的FIC以0.5FIC≤1和1FIC≤2为主,水飞蓟宾与环丙沙星或庆大霉素联用对革兰阴性试验菌的FIC以FIC2或1FIC≤2为主。结论水飞蓟宾对革兰阳性菌有较好的抑菌活性,其中对表皮葡萄球菌抑菌活性最强。水飞蓟宾的抑菌活性明显高于其他同分异构体。水飞蓟宾与青霉素/红霉素联用主要为相加和无关作用,与环丙沙星或庆大霉素联用主要为拮抗或无关作用。     

肠球菌感染的分离鉴定及耐药分析

目的：了解肠球菌引起医院感染的特点、临床分布及临床常用抗菌药物的耐药性。为临床治疗肠球菌感染提供指导。方法：应用MicroseanW／A-40细菌鉴定及药物分析系统对从医院感染者标本中分离的306株肠球菌进行鉴定及药敏测定。结果：306株肠球菌属中粪肠球菌205株,屎肠球菌87株,其他肠球菌14株,肠球菌属在各类感染性标本中的分离率以尿液、痰液、伤口分泌物最多,分别占43．2％、23．5％、18．3％。药敏结果显示：肠球菌对红霉素、庆大霉素、环丙沙星的耐药率分别是46．9％、78．6％、58．6％,对万古霉素的耐药率最小,为4．9％。结论：肠球菌属是主要造成医院感染的主要病原菌之一,以粪肠球菌多见。肠球菌属存在严重的耐药性,目前,万古霉素对肠球菌属具有较高的抗菌活性,其次为氨苄西林。     

国产罗红霉素体外抗菌作用的研究

 目的:研究国产罗红霉素体外杭菌作用，并同大环内醋类其它杭生素进行比较。方法:未用二倍平皿稀释法测定最低抑菌浓度(MIC)和影响因素的作用，采用试管二倍稀释法测定最低杀菌浓度(MBC)，未用平皿菌落计数法绘制杀菌曲线。结果:国产罗红霉素与红霉素具有交叉耐药性，红霉素的MIC多等于国产罗红霉素MIC的1/2或1/4。国产罗红霉素对于所采用实验菌株的MBC要大于MIC的4 --16倍。10⁶ CFU · ml ^-1以下的细菌接种量几乎不影响国产罗红霉素的MIC。随着pH的增高，细菌对国产罗红霉素的敏感性增大。人血清可使国产罗红霉素MIC升高。结论:国产罗红霉素的杭菌谱与红霉素相同，体外杭菌活性略弱于红霉素或相近，但优于交沙霉素、麦迪霉素和柱晶白霉素，为一抑菌药。     

三种方法处理金银花对根管粪肠球菌抑菌效果比较

目的：评价三种常用方法处理金银花后对根管粪肠球菌抑制效果的差异。方法：采用平板打洞法、试管倍比稀释法分别测定了三种方法处理的金银花药液的药物敏感性和最小抑菌浓度（MIC）。结果：三种方法处理的金银花药液对根管粪肠球菌均有抑制作用,相同浓度下,醇提液抑菌环最大,MIC浓度最小;其次为浸提液,水煎液抑菌效果最弱。结论：醇提法能够更好的提取金银花中抑菌成份。     

体外抑菌实验微量定量检测方法的建立与探索

 目的：介绍微量定性定量法（MQQA）,为抗菌药物的筛选和药敏试验提供一种新的方法。方法：以大肠杆菌、绿脓杆菌和金葡球菌为实验对象,以硫酸丁胺卡那霉素、庆大霉素2个已知药为工具药,用MQQA测出2个已知药对上述3个菌株的最小抑菌浓度（MIC）,并与平皿法和试管法进行比较。结果：MQQA的MIC值对细菌活性的影响,通过酶标仪测试其吸光度值,求出ED₅₀。结论：MQQA具有重要的应用价值,有利于抗菌药物的筛选和药敏实验的测试。     

Antibacterial steroid alkaloids from the stem bark of Holarrhena pubescens

Holarrhena pubescens (syn. H. antidysenterica) (L.) WALL. stem bark was tested for antibacterial efficacy against Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus faecalis, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa using the microdilution broth method as well as the disc diffusion method. The crude methanolic extract was active against all tested bacteria. Further chemical fractionation indicated that the antibacterial activity was mainly associated with the alkaloids. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined for the crude extract, the total alkaloids and the neutral fraction using microdilution broth method. The results were compared with reference antibiotics. The total alkaloids showed remarkable activity against S. aureus (MIC = 95 microg/ml).     

氟罗沙星体内外抗菌活性及抗生素后效应研究

 目的：对比研究氟罗沙星(FLRX)与其它氟喹诺酮类药物对临床分离致病菌的体内外抗菌活性及抗生素后效应(PAE)。方法：应用琼脂平板稀释法测定最低抑菌浓度(MIC)，微量稀释法测定血清杀菌效价(SBA)，吸光度法测定PAE。结果：FlRX对金葡菌、大肠埃希菌、肺炎克雷伯菌、绿脓假单胞菌均具很强的体内外抗菌活性，与氧氟沙星(OFLX)相似，而强于洛美沙星(LFLX)；FLRX对上述受试菌的峰时SBA与OFLX和LFLX相似，但谷时SBA多在1:1以上，高于OFLX和LFLX。FLRX无论对革兰阳性或阴性菌均具较长的PAE，呈显著的浓度依赖性，除金葡菌外，对其它受试菌的PAE均长于OFLX。结论：FLRX抗菌谱广，体内外抗菌活性强，具有较长时间的PAE，临床可采取每日1次给药方案治疗各类细菌感染。     

Total synthesis and biological evaluation of (5Z,9Z)-5,9-hexadecadienoic acid,an inhibitor of human topoisomerase I

The naturally occurring (5Z,9Z)-5,9-hexadecadienoic acid was synthesized stereochemically pure in six steps starting with commercially available 1,5-hexadiyne. The title compound was antimicrobial against the Gram-positive bacteria Staphylococcus aureus (MIC 80 microM) and Streptococcus faecalis (MIC 200 microM), but inactive against Gram-negative bacteria such as Pseudomonas aeruginosa. In addition, the (5Z,9Z)-5,9-hexadecadienoic acid completely inhibits human topoisomerase I at a concentration of 800 microM, while 5,9-hexadecadiynoic acid and hexadecanoic acid do not inhibit topoisomerase I (>1000 microM). This comparison reveals that the cis double bond geometry in the title compound is required for topoisomerase I inhibition. Moreover, these results suggest that the antimicrobial activity of (5Z,9Z)-5,9-hexadecadienoic acid against either S. aureus or S. faecalis could be a result, at least in part, of the inhibitory activity of the acid against topoisomerases.     

Evaluation of the antimicrobial potential of medicinal plants from the Ivory Coast

A total of 148 crude ethanol extracts from 115 plant species were tested in vitro against Gram-negative strains (Escherichia coli, Pseudomonas aeruginosa) and the Gram-positive Staphylococcus aureus and Enterococcus faecalis. Moreover, they were submitted to antifungal assays against Candida albicans and Cladosporium cucumerinum, a human and a plant pathogenic microorganism, respectively, known to be good indicators of antifungal activity. No activity was detected against the Gram-negative bacteria, while 14.8% and 10.8% of the extracts showed Gram-positive bactericidal or bacteriostatic effects on S. aureus and E. faecalis, respectively. An antifungal activity was observed with 15 extracts (10.1%). Two species were particularly active against the fungi: Dioscorea minutiflora and Erythrina vogelii. The young tubers of D. minutiflora contain metabolites with a specific effect on fungi and were not active against the bacteria. On the other hand, E. vogelii was highly effective against the Gram-positive bacteria and the fungi.     

牛至油及其主要成分的体外抑菌实验

目的：比较牛至油、香芹酚、百里香酚和对伞花烃对6株标准菌的抑菌效果。方法：采用滤纸片法以及试管二倍稀释法,以头孢曲松钠和氟康唑作为阳性对照,分别采用牛至油、香芹酚、百里香素、对伞花烃对金黄色葡萄球菌、肺炎克雷伯菌、粪肠球菌、大肠埃希菌、铜绿假单胞菌、葡萄牙念珠菌进行体外抑菌实验,测定抑菌圈的大小,最小抑菌浓度（MIC）以及最小杀菌浓度（MBC）。评价各试药的抑菌效果。结果：牛至油、香芹酚、百里香酚对不同标准菌株均有明显抑菌效果;滤纸片法显示牛至油、香芹酚、百里香酚对选定的6株菌株皆高度敏感,对伞花烃对其菌株耐药。试管二倍稀释法结果表明,牛至油、香芹酚抑菌效果稍强于百里香酚,但这3种植物挥发油对铜绿假单胞菌的抑菌效果与其他菌株相比较弱。结论：牛至油、香芹酚和百里香酚对金黄色葡萄球菌、肺炎克雷伯菌、粪肠球菌、大肠埃希菌、铜绿假单胞菌、葡萄牙念珠菌具有显著体外抑菌作用。     

Antimicrobial evaluation of certain plants used in Mexican traditional medicine for the treatment of respiratory diseases

Eighteen crude extracts, including six hexanic, six chloroformic and six methanolic from six different plant species used in Mexican traditional medicine for the treatment of respiratory infections, were evaluated for potential antimicrobial activity against Staphylococcus aureus, Enterococcus faecalis, Streptococcus pneumoniae, Streptococcus pyogenes, Escherichia coli, and Candida albicans. The minimal inhibitory concentration was determined for each extract using a two-fold dilution assay. The results showed that 16 crude extracts (89%) exhibited antimicrobial activity against at least one of the microorganisms tested at concentrations of 5 mg/ml or below. The extracts from Gnaphalium oxyphyllum, Gnaphalium americanum, and Crescentia alata possessed strong antimicrobial activity against the pathogens tested.     

斜叶檀和杠香不同提取物的体外抗菌活性初探

目的探究传统民族药斜叶檀(又称为斜叶黄檀,Dalbergia pinnata(Lour.)Prain)和杠香(又称为滇黔黄檀,Dalbergia yunnanensis Franch)不同提取物的体外抗菌活性。方法采用纸片扩散法探究斜叶檀及杠香的水蒸气蒸馏挥发油、超临界二氧化碳萃取挥发油、水提物及醇提物对金黄色葡萄球菌(Staphylococcus aureus S.aureus)、耐甲氧西林金黄色葡萄球菌(Methicillin Resistant Staphylococcus aureus,MRSA)、粪肠球菌(Enterococcus faecalis)、大肠埃希菌(Escherichia coli)、铜绿假单胞菌(Pseudomonas aeruginosa)及白念珠菌(Candida albicans,C.albicaus)的抑菌效果,并探究提取物浓度对敏感菌株抑菌活性的影响,同时进行最低抑菌浓度(Minimum Inhibitory Concentration,MIC)及最低杀菌浓度(Minimal Bactericidal Concentration,MBC及Minimal Fungicidal Concentration,MFC)的测定。结果两种药物不同的提取物均表现出不同程度的抑菌活性,且活性强弱与提取物浓度成正相关。二者水提物对两种葡萄球菌抑制效果明显,对粪肠球菌抑制效果稍逊;斜叶檀水蒸馏挥发油对白念珠菌抑制效果极强,抑菌圈直径大于30 mm。斜叶檀水蒸馏挥发油对白念珠菌的MIC和MFC均为220μg·mL-1;水提物对两种葡萄球菌的MIC及MBC均为625μg·mL-1。杠香水提物对两种葡萄球菌的抑菌作用均优于其水蒸馏挥发油。结论斜叶檀、杠香的水蒸馏挥发油及水提物有较好的抗菌活性,拥有进一步开发的潜力。     

Antimicrobial properties of Phrygilanthus acutifolius

Ethanol extract of flowers of Phrygilanthus acutifolius (Ruiz & Pav.) Eichler (Loranthaceae) inhibited the growth of both Gram (+) bacteria (Staphylococcus aureus, Staphylococcus saprophyticus and Enterococcus faecalis) and Gram (-) bacteria (Serratia marcescens, Acinetobacter sp. and Pseudomonas aeruginosa). This extract was bactericidal against Staphylococcus aureus and bacteriostatic against Pseudomonas aeruginosa. Morphological evidence suggests that the extract causes the swelling of the bacterial body of Staphylococcus aureus, the disintegration of the cell surface and the cell death. Bactericidal activity was optimal at pH 7.5 and was not affected by different ionic strengths. The presence of Mg2+ in the culture medium of Phrygilanthus acutifolius diminished the sensitivity of Pseudomonas aeruginosa strain against the extract. Test results would tend to corroborate the folk belief that the flowers of this plant are efficacious against respiratory infections and would justify its further investigation.     

Ursolic, oleanolic and betulinic acids: antibacterial spectra and selectivity indexes

ETHNOPHARMACOLOGICAL RELEVANCE: Ursolic acid (UA), oleanolic acid (OA) and betulinic acid (BA), three hydroxyl pentacyclic triterpenoic acids (HPTAs) naturally found in a large variety of vegetarian foods, medicinal herbs and plants have been investigated for antibacterial activity. AIM OF THE STUDY: To determine the antibacterial activity of UA, OA and BA, as well as the toxic impact on eukaryotic cells. MATERIALS AND METHODS: Minimum inhibitory concentrations were determined against five reference strains (Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923 & ATCC 29213, Enterococcus faecalis ATCC 29212 and Pseudomonas aeruginosa ATCC 27853), as well as five antibiotic-resistant clinical isolates. Toxicity was evaluated against MRC-5 and HaCaT cell lines. RESULTS: No antibacterial activity was observed for BA; while OA and more particularly UA, did show a moderate to good antibacterial activity, but limited to Gram-positive bacteria. Nevertheless, OA and UA were devoid of antibacterial activities against clinical isolates. Moreover, viability and cytotoxic assays demonstrated that the three compounds induced a significant cytotoxicity. CONCLUSIONS: Despite of a relative similar chemical structure; UA, OA and BA harboured different antibacterial activities, with more significant ones for UA. However, considering both viability and toxicity values, these compounds seem to have a significant impact on eukaryotic cell viability.