中草药提取物的体外抑菌活性研究

目的探讨10种中草药提取物的体外抗菌活性。方法制备10种中草药提取物,采用试管连续稀释法对金黄色葡萄球菌、大肠埃希菌、铜绿假单胞菌和白色念珠菌进行体外抑菌试验。结果10种中草药的提取物对金黄色葡萄球菌、大肠埃希菌、铜绿假单胞菌和白色念珠菌有不同程度的抑制活性;其中尤以赤芍、石榴皮、五味子和黄连的提取物抗耐药菌活性最高,赤芍提取物对上述4种菌的抑制活性均较高,其最低抑菌浓度(MIC)分别为7.80、1.95、1.957、.80 mg/ml。结论赤芍、石榴皮、五味子和黄连提取物呈现广谱抗菌特性,且具有抗耐药菌作用。     

214例鲍氏不动杆菌的感染分布及耐药性

目的了解鲍氏不动杆菌感染的临床分布及其耐药特点.方法收集2003年1月～2004年12月从临床感染标本的214株鲍氏不动杆菌,了解其临床分布并做药敏试验,比较其耐药率.结果214株鲍氏不动杆菌临床分布以ICU最多（61株,28.5%）,且多见于老年患者（97株,45.3%）;对三代头孢及环丙沙星的耐药率均＞50.0%;对美罗培南,亚胺培南/西司他丁,头孢哌酮/舒巴坦的耐药性较低,分别为4.2%、7.9%、8.9%;发现131株（61.2%）多重耐药菌株.结论碳青酶烯类及头孢哌酮/舒巴坦对鲍氏不动杆菌感染仍有较强的活性,但不能忽视对这两类药物耐药的多重耐药菌株的出现,要减少多重耐药菌株的产生,应注意合理使用抗菌药物.     

金钗石斛的研究进展

金钗石斛是常用中药,为兰科(Orchidaceae)石斛属(Dendrobium Sw.)植物金钗石斛(D.nobile Lindl.)的新鲜或干燥茎,其化学成分类型主要有生物碱类、酚类、多糖类等,其中生物碱类为主要成分;药理作用主要有抗肿瘤、抗衰老、增强机体免疫力、抗白内障和抗菌等作用.对其化学成分、药理作用及临床应用情况进行分类总结,为金钗石斛的进一步研究开发提供依据.     

Structural and biological characterization of three novel mastoparan peptides from the venom of the neotropical social wasp Protopolybia exigua (Saussure).

The venom of the Neotropical social wasp Protopolybia exigua(Saussure) was fractionated by RP-HPLC resulting in the elution of 20 fractions. The homogeneity of the preparations were checked out by using ESI-MS analysis and the fractions 15, 17 and 19 (eluted at the most hydrophobic conditions) were enough pure to be sequenced by Edman degradation chemistry, resulting in the following sequences: Protopolybia MPI I-N-W-L-K-L-G-K-K-V-S-A-I-L-NH2 Protopolybia-MP II I-N-W-K-A-I-I-E-A-A-K-Q-A-L-NH2 Protopolybia-MP III I-N-W-L-K-L-G-K-A-V-I-D-A-L-NH2 All the peptides were manually synthesized on-solid phase and functionally characterized. Protopolybia-MP I is a hemolytic mastoparan, probably acting on mast cells by assembling in plasma membrane, resulting in pore formation; meanwhile, the peptides Protopolybia-MP II and -MP III were characterized as a non-hemolytic mast cell degranulator toxins, which apparently act by virtue of their binding to G-protein receptor, activating the mast cell degranulation.     

Antimicrobial activity of myotoxic phospholipases A2 from crotalid snake venoms and synthetic peptide variants derived from their C-terminal region.

A short peptide derived from the C-terminal region of Bothrops asper myotoxin II, a Lys49 phospholipase A(2) (PLA(2)), was previously found to reproduce the bactericidal activity of its parent molecule. In this study, a panel of eight PLA(2) myotoxins purified from crotalid snake venoms, including both Lys49 and Asp49-type isoforms, were all found to express bactericidal activity, indicating that this may be a common action of the group IIA PLA(2) protein family. A series of 10 synthetic peptide variants, based on the original C-terminal sequence 115-129 of myotoxin II and its triple Tyr-->Trp substituted peptide p115-W3, were characterized. In vitro assays for bactericidal, cytolytic and anti-endotoxic activities of these peptides suggest a general correlation between the number of tryptophan substitutions introduced and microbicidal potency, both against Gram-negative (Salmonella typhimurium) and Gram-positive (Staphylococcus aureus) bacteria. Peptide variants with high bactericidal activity also tended to be more cytolytic towards skeletal muscle C2C12 myoblasts, thus limiting their potential in vivo use. However, the peptide variant pEM-2 (KKWRWWLKALAKK) showed reduced toxicity towards muscle cells, while retaining high bactericidal potency. This peptide also showed the highest endotoxin-neutralizing activity in vitro, and was shown to functionally interact with lipopolysaccharide (LPS) using a chimeric bacteria model. The bactericidal and anti-endotoxic properties of pEM-2, combined with its relatively low toxicity towards eukaryotic cells, highlight it as a promising candidate for further evaluation of its antimicrobial potential in vivo.     

Purification and characterization of a novel peptide with antifungal activity from Bothrops jararaca venom.

Different peptides have been isolated from a wide range of animal species. It is has become increasingly clear that due to the development of antibiotic-resistant microbes, antibacterial and antifungal peptides have attracted the attention in recent years, in order to find new therapeutic agents. In this work, a novel peptide with high inhibitory activity against fungi growth have been isolated from the venom of the Brazilian snake Bothrops jararaca. A Sephacryl S-100 gel filtration column was employed for further separation of proteins. The FV fraction with high antifungal activity was named Pep5Bj, pooled and submitted to reverse-phase chromatography in HPLC. The fraction containing the isolated peptide inhibited the growth of different phytopathogenic fungi (Fusarium oxysporum and Colletotrichum lindemuthianum) and yeast (Candida albicans and Saccharomyces cerevisiae). The peptide minimal inhibitory concentration is comparable to other known antifungal peptides, like insect defensins and cecropins, found in the last years in a large diversity of animals. We investigate F. oxysporum cells membrane permeabilization using SYTOX Green uptake, an organic compound that fluoresces upon interaction with nucleic acids after penetration in cell with compromised plasma membranes. When viewed under fluorescence optical microscopy, F. oxysporum cells exposed to Pep5Bj display strong SYTOX Green fluorescence in the cytosol, especially in the nuclei. The SYTOX Green data suggested that this effect is related to membrane permeabilization. The molecular masses of this peptide was obtained by MALDI-TOF spectrometry and corresponded to 1370Da.     

16种中成药微生物限度检查法方法验证

目的:建立16种中成药的微生物限度检查方法.方法:采用5种阳性对照菌回收率试验测定其是否含抑菌成分.结果:根据回收率试验结果,感冒清片、干柏鼻炎片、清开灵口服液、清热解毒口服液、感冒清热颗粒和板兰根颗粒6种供试品试验菌的回收率试验均高于70%,证明无抑菌现象;热炎宁颗粒、黄连上清丸、牛黄上清丸、三七伤药片和双黄连口服液有一定程度的抑菌作用,但可通过稀释法消除抑菌作用;霍香正气滴丸、三黄片、清喉利咽颗粒、复方丹参片和牛黄解毒片的抑菌作用强,必须采用离心集菌加薄膜过滤法才能彻底消除其抑菌作用.结论:感冒清片、干柏鼻炎片、清开灵口服液、清热解毒口服液、感冒清热颗粒和板兰根颗粒按常规方法进行微生物限度检查;热炎宁颗粒、黄连上清丸、牛黄上清丸、三七伤药片和双黄连口服液按培养基稀释法进行微生物限度检查;藿香正气滴丸、三黄片、清喉利咽颗粒、复方丹参片、牛黄解毒片按离心集菌加薄膜过滤法进行微生物限度检查.     

氧代固醇衍生物的合成及其抗癌活性研究

目的合成新型氧代固醇衍生物并对其抗癌活性进行研究.方法以胆甾烷-3β,5α,6β-三醇为原料合成氧代固醇琥珀酸单酯的一乙醇胺盐系列化合物;以各种含羟基固醇化合物为原料,分别与正丁酰氯等反应合成氧代固醇的正丁酸酯系列化合物.并对这两类化合物进行了体外抗癌活性试验.结果与结论共合成13个未见文献报道的氧代固醇类化合物,结构经IR、1H-NMR以及元素分析得到确证,初步体外药理试验表明:化合物4具有很好的抗癌活性.     

清洁手术的围手术期抗菌药物预防使用分析

目的:观察术前 术后未使用抗菌药,仅术前使用抗菌药和术前 术后均使用抗菌药三组病人清洁手术的切口愈合情况.方法:将三组病人术后情况进行统计分析.结果:三组病人切口愈合情况无显著性差异.结论:清洁手术术后一般不需要应用抗菌药物预防切口感染.     

FRu（phen）2（3，8—2R—phen）-]^2＋（R=OH，H，F）电子结构与抗癌活性研究

用密度泛函(DFT)法，对配合物[Ru(phen)2(3，8-2R—phen)^2 (R=OH，H，F)进行了理论计算研究。探讨了配合物的电子结构与其抗癌活性的关系：主配体上3，8位上F原子的取代有利于配合物与DNA的作用，增加配合物的抗癌活性。计算结果能较好地预测配合物与DNA的作用强度、抗癌活性及指导具有较高抗癌活性配合物的合成。