喹诺酮杂合体的抗耐甲氧西林金葡菌活性研究进展

耐甲氧西林金葡菌(MRSA)是引起院内和社区感染的重要病原菌,高发病率与致死率使得其位居感染病原菌之首。MRSA是多重耐药致病菌,目前已对包括万古霉素在内的几乎所有抗生素产生了不同程度的耐药性。因此,开发新型抗MRSA药物刻不容缓。喹诺酮尤其是氟喹诺酮是临床上广泛使用的一类广谱抗菌药,对包括某些MRSA在内的多种致病菌引起的感染具有良好的疗效。杂合体具有多个药效团可同时作用于不同的药物靶点,故杂合体策略是克服耐药性的常用策略。喹诺酮与其它抗MRSA药效团相结合所得的杂合体可发挥协同作用,寻找新型抗MRSA药物的潜力分子。近年来,药物化学家设计合成评价了多个系列喹诺酮杂合体的抗MRSA活性,发现了多个具有进一步研究价值的潜在化合物。本文将着重介绍2015—2022年间所发展的具有抗MRSA活性的喹诺酮杂合体的研究进展,并归纳构-效关系,为进一步合理设计此类杂合体提供一定的理论支持。     

耐甲氧西林金葡菌的研究进展

耐甲氧西林金葡菌已成为医院及社区感染的主要病原菌之一.经重组获得的mec复合体是其产生耐药性的结构基础,并通过产生PBP2a表达抗药性,而金葡菌耐药性表达及表达程度还受其内在的固有基因影响.本文就其流行病学、耐药机制及检测方法研究进展作一综述.     

650株耐甲氧西林金葡菌的感染现状及耐药性分析

目的:分析江苏大学附属医院临床耐甲氧西林金黄色葡萄球菌(MRSA)的分布特点及耐药情况。方法:采用回顾性统计与分析方法,对2009年—2011年3年间临床送检的医院住院患者的各类标本中分离出的MRSA的病原菌,对其感染现状及耐药性进行分析。结果:3年间各类送检标本中分离出金黄色葡萄球菌984株,经筛选,其中MRSA为650株,占66.06%;痰与分泌物的标本中分离率为最高,占95.38%(620/650);MRSA的检出率呈上升趋势,并对大多数抗菌药物产生不同程度的耐药,尚未发现对万古霉素、替考拉宁、利奈唑胺的耐药菌株。结论:MRSA的检出率及耐药率逐年升高,且多重耐药性现象严重;应加强行政干预,采取多渠道、多部门联合的综合防控措施以遏制MRSA耐药率的增长。     

耐甲氧西林金葡菌的耐药分子机制研究

自1961年发现第一株耐甲氧西林金葡菌(MRSA)至今,其耐药问题已严重影响临床抗感染治疗的疗效,引起广泛重视。近年来,随着分子生物技术的不断发展,人们对其耐药机制的研究逐步深入。对MRSA耐药机制的研究进展,特别是耐β-内酰胺类抗生素的分子机制,包括其耐药决定性基因mecA基因,以及fem基因等其他辅助基因进行重点介绍。     

耐甲氧西林金葡菌感染的免疫治疗开发

耐甲氧西林金葡菌(MRSA)感染致病率和致死率不断上升,特别是万古霉素耐药金葡菌的出现,对人类健康构成了极大的威胁。尽管新型抗MRSA小分子化学药物的上市,对控制MRSA感染起到了重要的作用,但多个处于不同临床研究阶段的免疫治疗药物展现了独特的抗MRSA感染效果。本文简要综述针对MRSA感染的主动免疫和被动免疫治疗药物开发进展。     

耐甲氧西林金葡菌到万古霉素高度耐药金葡菌的发展及其感染的药物治疗

随着万古霉素用量增加,耐甲氧西林金葡菌(MRSA)对万古霉素敏感性逐渐下降.依据其对万古霉素敏感性的差异可分成异质性万古霉素中度耐药金葡菌(hVISA)、万古霉素中度耐药金葡菌(VISA)和万古霉素高度耐药金葡菌(VRSA)等3类.本文简要综述卜述3类金葡菌的发展、相关耐药机制及其感染的药物治疗现状.     

耐甲氧西林金葡菌对抗菌药物的耐药表型和基因型分析

目的 了解来自汕头和北京地区的67株耐甲氧西林金葡菌(MRSA)的耐药情况及耐药机制,并分析耐药表型与基因型的一致情况.方法 以琼脂稀释法测定24种抗菌药物对MRSA的体外抗菌活性,PCR扩增MRSA的耐药基因,nitrocefin测定细菌产β-内酰胺酶的情况.结果 67株MRSA除了对氯霉素和多西环素的耐药率较低,分别为3%和7.5%,对万古霉素、米诺环素和利凡诺100%敏感外,对利福平的耐药率为52.2%,对四环素的耐药率为77.6%,而对于其它包括青霉素、第1～4代头孢菌素、单环β-内酰胺类、碳青霉烯类、氨基糖苷类和磺胺类的耐药率均在80%～90%以上,氨苄西林加酶抑制剂以后则耐药程度有所降低.qacA/B、mecA、tetM、NorA、gyrA、aac(6')/aph(2")、aph(3')Ⅲ和β-内酰胺酶检出率分别为11.9%、95.5%、70.1%、4.5%、10.4%、82.1%、73.1%和92.5%,未检出qacC、ant(6)-I、ant(2")-I、VanA和VanB耐药基因.67株MRSA均携带有多种耐药基因:同时携带2种耐药基因的有7株,3种的有10K,4种的有11株,5种的29株,6种的10株.结论 67株MRSA耐药情况严重,并同时携带多种耐药基因.     

新型抗耐甲氧西林金葡菌抗生素研究进展

随着临床耐药病例日益增多,耐甲氧西林金葡菌(MRSA)己成为医院和社区获得性感染的主要元凶.MRSA蔓延趋势不断恶化,新型抗MRSA抗生素研究成为热点.本文综述新型抗MRSA抗生素特拉万星、头抱毗普与头抱洛林等新药的研究进展.     

Two new 2-(2-phenylethyl)chromones from Chinese eaglewood

Two new 2-(2-phenylethyl)chromones, (5S ^*,6R ^*,7S ^*)-5,6,7-trihydroxy-2-(3-hydroxy-4-methoxyphenethyl)-5,6,7,8-tetrahydro-4H-chromen-4-one (1) and (5S ^*,6R ^*,7R ^*)-5,6,7-trihydroxy-2-(3-hydroxy-4-methoxyphenethyl)-5,6,7,8-tetrahydro-4H-chromen-4-one (2), were isolated from the Chinese eaglewood of Aquilaria sinensis (Lour.) Gilg. Their structures were established by detailed MS and NMR spectroscopic analysis, as well as comparison with the literature data.     

Two new sesquiterpene derivatives from Chinese eaglewood

Two new sesquiterpene derivatives, (+)-8β-hydroxy-longicamphenylone (1) and 11β-hydroxy-13-isopropyl-dihydrodehydrocostus lactone (2), were isolated from Chinese eaglewood. Their structures were elucidated on the basis of spectroscopic analyses including HR-ESI-MS, ¹H and ¹³C NMR, DEPT, ¹H–¹H COSY, HSQC, HMBC, and NOE. The two compounds exhibited potent anti-depressant activity in vitro by inhibiting [³H]-5-HT reuptake in rat brain synaptosomes by 54.8% and 51.9%, respectively, at 10 μM.     

沉香中精油的超临界CO2萃取及其GC-MS分析

目的 用超临界CO2流体萃取沉香中的精油.方法 采用正交试验优化超临界CO2流体萃取沉香精油的工艺,并用GC-MS分析其化学成分.结果与结论 最佳工艺条件为:萃取压力18 Mpa、萃取温度40℃、萃取时间2 h、沉香药材粉末过40目筛,萃取率达0.62%;共分离出39个组分,鉴定了其中的34个成分.首次分离出γ-芹子烯、α-可巴烯-8-醇、广藿香醇(3种倍半萜化合物)、5-羟基-7-甲氧基-2-戊色酮、8-甲氧基-2-(2-苯乙基)色烯-4-酮、7-苄氧基-甲酰色烯-4酮(3种色酮化合物).     

藏药独一味地上和地下部分挥发油成分的GC—MS分析

目的：研究藏药独一味地上和地下部分挥发油的化学成分。方法：用水蒸气蒸馏法提取藏药独一味地上和地下部分挥发油并通过气相色谱-质谱技术对其进行分析。结果：从藏药独一味地上部分挥发油中分离鉴定了16个组分，占总峰面积含量的92．9％．地下部分挥发油中分离鉴定了13个组分，占总峰面积含量的95．47％。结论：藏药独一味地上和地下部分挥发油主要是由长链脂肪酸成分构成，其中含量最多的是棕榈酸。     

GC-MS分析白鲜皮的挥发油成分

目的研究白鲜皮挥发油的化学成分。方法用水蒸气蒸馏法提取白鲜皮挥发油并用气相色谱-质谱技术分析。结果从白鲜皮挥发油中分离鉴定了31个组分,占总峰面积含量的86.17%。结论白鲜皮挥发油主要由倍半萜类化合物和长链脂肪酸成分构成,而倍半萜类化合物是其主要活性成分。     

HPLC和GC-MS检测两种提取法所得当归挥发油的化学成分

目的 比较两种提取方法所得挥发油的化学成分.方法 当归药材用水蒸气蒸馏和石油醚提取,用HPLC和GC-MS两种方法比较提取物.结果 HPLC和GC-MS分析当归两种提取方法所得两种挥发油,分别占100%、50%和34%、43%.石油醚法所得苯酞类化合物的种类比水蒸气蒸馏法的多.后者提取的为小分子易挥发的烯萜类成分,与文献报道相同.石油醚法收率是水蒸气蒸馏提取的2.5倍.结论 两种提取法所得挥发油化学成分有差异,石油醚提取当归挥发油较好.     

Volatile composition and antimicrobial activity of the essential oil of Artemisia absinthium growing in Western Ghats region of North West Karnataka,India

Abstract

Context: Artemisia absinthium L. (Asteraceae) is an aromatic, herbaceous, perennial plant commonly known as wormwood. Artemisia absinthium is traditionally used as an anthelmintic, antiseptic, antispasmodic and for bacillary dysentery, cancers and neurodegenerative diseases.

Objective: The essential oil composition of the leaves of A. absinthium growing in the Western Ghats region of North West Karnataka, India, is investigated for the first time in this region and the oil was screened for antimicrobial properties.

Materials and methods: The chemical composition of the hydro-distilled essential oil obtained from the leaves of A. absinthium was analyzed by GC-FID and GC/MS. The oil was tested against five Gram positive and, eight Gram negative bacteria and three fungi by the tube-dilution method at a concentration range of 5000–9?µg/mL.

Results: Results demonstrated that the leave oil was found to be rich in oxygenated monoterpenes (39.7% and 41.1%). The major compounds were borneol (18.7% and16.7%), methyl hinokiate (11.9% and 12.9%), isobornyl acetate (4.0% and 4.7%), β-gurjunene (3.8% and 4.4%) and caryophyllene oxide (3.7% and 4.3%), among 64 identified compounds, comprising 91.7% and 90.1% of the total oil. The organism Micrococcus luteus was found more susceptible to the oil with an MIC value of 25?±?4?µg/mL, followed by Micrococcus flavus, Bacillus subtilis, Penicillium chrysogenum and Aspergillus fumigatus with MIC values of 58?±?8, 65?±?8, 84?±?15 and 91?±?13?µg/mL, respectively.

Discussion and conclusion: The oil showing antimicrobial activity against bacteria and fungi validate the traditional use of the plant as an antiseptic.     

肉桂挥发油化学成分的GC/MS分析

对肉桂采用水蒸气回流法提取挥发油。用毛细管气相色谱 -质谱联用程序升温方法对肉桂挥发油化学成分进行分析,共鉴定了 35个化学成分,占挥发油相对含量的 96 %以上。     

Antimicrobial activity and chemical composition of the essential oil of Hofmeisteria schaffneri

Objectives The aims of this study were to establish the antimicrobial potential of Hofmeisteria schaffneri essential oil and its chemical composition. Methods The essential oils of Hofmeisteria schaffneri harvested at flowering (batches I and IV) and non‐flowering (batches II and III) seasons were prepared by hydrodistillation and analysed by GC and GC‐MS. The aqueous and organic (CH₂Cl₂‐MeOH 1 : 1) extracts were prepared by using infusion and maceration techniques, respectively. The in‐vitro antimicrobial activity of the preparations and compounds against Candida albicans and some bacteria (Gram‐negative and Gram‐positive) was assessed using the broth dilution method in 96‐microplate wells. Key findings Forty‐four compounds, representing ～90% of the total constituents, were identified in the essential oil of Hofmeisteria schaffneri collected in flowering (batches I and IV) and non‐flowering (batches II and III) seasons. In all cases, several thymol analogues were the major components of the oils (～65%); some small differences in the relative proportions of these constituents were observed. The infusion exhibited an antibacterial activity against Staphylococcus aureus and Bacillus subtilis, with a MIC value of 64 µg/ml in each case. The essential oil batches were active against Staphylococcus aureus, with MIC ranging from 48 to 192 µg/ml. They were, however, inactive against Gram‐negative bacteria, including Pseudomonas aeruginosa, Escherichia coli and Salmonella typhi (MIC > 1024 µg/ml). On the other hand, the infusion of the plant as well as the oil from batch I displayed anti‐Candida albicans activity, with MIC of 128 and 192 µg/ml, respectively. Finally, the organic extract did not displayed significant activity against the tested microorganisms (MIC ≥ 1024 µg/ml). Some of the compounds isolated from the plant were also tested. Compounds 8 and 38, which were present in the essential oils, displayed the best antibacterial effect against Gram‐positive bacteria (MIC ranging between 32 and 64 µg/ml). Compounds 6 (present in the infusion) and 10 (present in all preparations) showed higher activity against the yeast (MIC = 128 µg/ml) than the remaining compounds, with MIC values ranging from 256 to 512 µg/ml. Conclusions The composition and antimicrobial activity of the oils changed slightly from flowering to non‐flowering seasons. The results of the present investigation provide in‐vitro scientific support for the use of the plant against skin infections in Mexican folk medicine.     

Chemical composition and acetylcholinesterase inhibitory activity of Artemisia maderaspatana essential oil

Abstract

Context: To date, there are no reports to validate the Indian traditional and folklore claims of Artemisia maderaspatana L. (syn. Grangea maderaspatana L.) (Asteraceae) for the treatment of Alzheimer’s disease.

Objective: The present study characterizes the volatile components (non-polar compounds) of A. maderaspatana and evaluates its acetylcholinesterase inhibition potential.

Materials and methods: The essential oils (yield 0.06% v/w) were obtained from fresh aerial part of A. maderaspatana. The characterization of volatile components (non-polar compounds) was performed by GC–MS data and with those of reference compounds compiled in the spectral library of in-house database. The in vitro acetylcholinesterase (AChE) inhibition of the volatile organic constituents (VOC’s) of A. maderaspatana aerial part was evaluated in varying concentration ranges (0.70–44.75?µg/mL) with Ellman’s method.

Results: The major components were α-humulene (46.3%), β-caryophyllene (9.3%), α-copaene (8.2%), β-myrcene (4.3%), Z(E)-α-farnesene (3.7%), and calarene (3.5%). Chemical variability among other Artemisia spp. from different climatic regions of India and countries namely Iran and France was observed. The experimental results showed that diverse volatile organic constituents of A. maderaspatana have significant acetylcholinesterase inhibitory activity (an IC₅₀ value of 31.33?±?1.03?µg/mL). This is the first report on the inhibition of acetylcholinesterase properties of essential oil of A. maderaspatana obtained from fresh aerial part.

Conclusions: The present results indicate that essential oil of A. maderaspatana isolated from the northern region of India could inhibit AChE moderately. Therefore, the possibility of novel AChE inhibitors might exist in VOCs of this plant.