艾滋病合并新生隐球菌感染的研究进展

新生隐球菌感染是全世界艾滋病患者死亡的主要原因,尤其是在撒哈拉以南非洲地区发病率最高[1]。新生隐球菌除了容易感染HIV个体外,还易感染其他免疫功能低下的个体,如造血系统恶性肿瘤、器官移植后服用免疫抑制剂及免疫缺陷病患者。格特隐球菌主要侵犯免疫功能正常的个体,但也感染免疫功能低下患者如合并艾滋病毒的患者[2]。     

新生隐球菌荚膜研究现状

新生隐球菌是一种专性需氧条件致病菌,它的细胞壁外包绕着一个多糖荚膜,是其主要毒性因子之一。荚膜主要包含两种多糖-葡萄糖醛酸木糖和半乳糖甘露聚糖,此外还有少部分的甘露糖蛋白。这些多糖分子除构成多糖荚膜外,同时也参与新生隐球菌与宿主之间的免疫反应。该文对新生隐球菌荚膜的结构、生物合成、免疫反应及针对荚膜的抗真菌治疗等方面作一综述,旨在为新生隐球菌相关疾病的研究提供新的思路。     

脱氧胆酸钠体外对新生隐球菌胞外磷脂酶的作用

目的比较观察脱氧胆酸钠体外对自然生长条件下的新生隐球菌新生变种(CZYD7)胞外磷脂酶的抑制作用。方法在37℃下,用蛋黄平板法培养并测量菌株产生沉淀圈的大小,用沉淀圈比值(PZ值)比较磷脂酶活力的变化。结果对照组与脱氧胆酸钠不同浓度组(依次为0.1%、0.2%、0.3%和0.4%)的PZ值分别为0.390±0.050,0.782±0.038,0.875±0.074,0.914±0.048,0.885±0.091;脱氧胆酸钠各浓度组与对照组比较均有显著差异(P<0.01)。脱氧胆酸钠不同浓度组间PZ值比较,0.1%和0.2%、0.1%和0.3%、0.1%和0.4%组间有显著差异(P<0.05)。结论脱氧胆酸钠体外对新生隐球菌新生变种CZYD7株胞外磷脂酶具有抑制作用。     

昆仑雪菊提取物对α- 葡萄糖苷酶的抑制作用

目的:探讨昆仑雪菊提取物对α-葡萄糖苷酶的抑制活性。方法:将昆仑雪菊干燥花序粉碎,分别用水提法和乙醇法制备5种提取物。采用α-葡萄糖苷酶体外活性抑制模型,测定昆仑雪菊的5种提取物对α-葡萄糖苷酶的抑制活性。结果:这5种提取物对α-葡萄糖苷酶活性有较强的抑制作用,抑制活性均高于阿卡波糖。其中提取物Ⅰ的抑制活性最强,IC50=28.2 mg/L。结论:昆仑雪菊提取物具有较高的α-葡萄糖苷酶抑制活性,提示昆仑雪菊在抗糖尿病产品开发方面具有很好的应用前景。     

昆仑雪菊提取物对α-葡萄糖苷酶的抑制作用

目的：探讨昆仑雪菊提取物对α-葡萄糖苷酶的抑制活性。方法：将昆仑雪菊干燥花序粉碎,分别用水提法和乙醇法制备5种提取物。采用α-葡萄糖苷酶体外活性抑制模型,测定昆仑雪菊的5种提取物对α-葡萄糖苷酶的抑制活性。结果：这5种提取物对α-葡萄糖苷酶活性有较强的抑制作用,抑制活性均高于阿卡波糖。其中提取物Ⅰ的抑制活性最强,IC50=28.2 mg/L。结论：昆仑雪菊提取物具有较高的α-葡萄糖苷酶抑制活性,提示昆仑雪菊在抗糖尿病产品开发方面具有很好的应用前景。     

新生隐球菌的荚膜多糖合成研究进展

新生隐球菌是一重要的致病真菌,其细胞壁外层的多糖荚膜是第1个被公认的新生隐球菌毒性因子。本文总结了在荚膜生理和生化合成方面的研究进展,介绍了研究新生隐球菌荚膜合成的常用方法以及在新生隐球菌的荚膜代谢途径、生化合成酶、分泌、组装和调节这些广泛的研究领域存在的许多未解决的问题。     

树突细胞与新生隐球菌

新生隐球菌( Cn) 是临床上重要的病原真菌, 树突细胞( DC) 则是最重要的抗原呈递细胞。作为宿主固有免疫和适应性免疫的联系枢纽,DC 对于识别病原、呈递抗原、诱导宿主免疫应答十分重要。许多研究证明,DC 可通过细胞表面的多种受体有效识别新生隐球菌抗原( CnAg) , 诱导宿主产生有效的细胞免疫应答。DC 本身也有一定的杀菌能力, 但DC 的不同亚群以及成熟状态对宿主的免疫防御功能有重要影响。另外, 隐球菌除具有甘露糖蛋白等主要免疫显性抗原外, 还有多种抑制机体保护性免疫应答的毒性因子。本文就近年来国内、外对两者之间复杂机制的研究进行概述。     

对两种新生隐球菌选择性培养基的比较研究

比较鸟籽琼脂（GASA,Guizotia abyssinica seed agar）和咖啡酸玉米琼脂（CACA,Caffeic acidcommeal agar）对新生变种和格特变种的培养效果。再同时用两种培养基分离命粪和澳洲赤桉标本中的新生隐球菌。结果表明,CACA对新生隐球菌的培养和选择性分离效果与GASA相同,能够用于新生隐球菌的选择性分离。     

一株尿素酶阴性的新生隐球菌

本文报告从鸽粪标本中分离出的一株尿素酶试验阴性、咖啡酸玉米吐温琼脂培养呈棕色菌落的酵母样真菌。根据该菌袜的生理、生化特性及致病力,认为是尿素酶阴性的新生隐球菌。此外,应注意这种菌在自然界中的存在和对人类造成感染的可能。这是关于从自然环境中分离出尿素酶阴性新生隐球菌的首次发现和报告。     

Chemical composition and antimicrobial activity of Satureja hortensis L. essential oil

Essential oil of Satureja hortensis L. was analyzed by GC and GC/MS and tested by a broth micro-well dilution method for activity against multiresistant clinical isolates of pathogenic bacteria from 10 different genera: Klebsiella, Escherichia, Proteus, Staphylococcus, Streptococcus, Pseudomonas, Enterococcus, Enterobacter, Citrobacter and Acinetobacter. The main compounds in the oil were carvacrol (67%), γ-terpinene (15.3%) and p-cymene (6.73%). The oil showed activity against all tested strains. MIC/MBC values were in the range of 0.78-25 μl/ml, with the exception of the strain P. aeruginosa. Microbicidal concentration for this particular strain (50 μl/ml) was the highest tested concentration. The oil showed inhibitory and bactericidal effect at the same concentration (MIC=MBC) for all but three strains.     

Anti‐Lipid Peroxidation, α‐Glucosidase and α‐Amylase Inhibitory Effects of the Extract of Capitula of Coreopsis tinctoria Nutt. and Protection Effects on High‐Fat/High‐Sugar and Streptozotocin‐Induced Type 2 Diabetes in Mice

Coreopsis tinctoria capitula (CTC) of the Compositae family has been used traditionally to treat various diseases in China, particularly type 2 diabetes mellitus (T2DM). This study evaluated the anti‐lipid peroxidation, α‐glucosidase and α‐amylase inhibitory effects of CTC extracts, and analyzed its chemical composition by HPLC. Moreover, the antioxidant activity and protection effects of CTC extracts were investigated on high‐fat/high‐sugar and streptozotocin‐induced T2DM mice. In vitro study, the ethyl acetate extract (EAE) and butanol extract (BE) of CTC exhibited anti‐lipid peroxidation (IC₅₀: BHA>BE or EAE>ascorbic acid, p<0.05) and α‐glucosidase inhibitory activity (IC₅₀: BE>EAE, p<0.05). In vivo, the BE at the dose of 600 mg/kg was intragastrically given to T2DM mice, which exhibited a certain extent of repair and improvement of the levels of CAT, GSH, GSH‐P_X, SOD, as well as plasma biomarkers, compared with those in the model group (p<0.05). These results demonstrated that CTC extracts have a positive effect to treat T2DM and it can be used for the treatment of T2DM in the future.     

Antimicrobial activity and chemical composition of essential oil from Helichrysum microphyllum Cambess. subsp. tyrrhenicum Bacch., Brullo & Giusso collected in South-West Sardinia

The aim of this study was to evaluate the chemical composition and the antimicrobial activity of essential oils of Helichrysum microphyllum subsp. tyrrhenicum collected in four different stations in South-Western Sardinia.The composition of the essential oils was determined by gas chromatography and gas chromatography/mass spectrometry. The oil samples showed different chromatographic profiles. The oil of the station 4 revealed the presence of significant amount of neryl acetate (33.6%); in oils from stations 1 and 2 we found γ-curcumene (28%) and in station 3 γ-curcumene (12%) and linalool (11%), while there was no trace of neryl acetate. Standard microbiological assays demonstrated that essential oils obtained by plants collected in station 1 and 2, very rich in curcumene, showed an interesting anticandidal activity, dose- and time-dependent, which is enhanced by sub-inhibitory concentrations of chitosan.Our results suggest that the essential oil of Helichrysum microphyllum subsp. tyrrhenicum, associated with chitosan in innovative formulations, could be considered as a therapeutic alternative in the treatment of Candida opportunistic infections. The results of this study shows that the chemotypization of the species examined could lead to their targeted clinical use, in a concept of a rational scientific aromatherapy.     

几种典型植物精油的化学成分与其抗菌活性

【目的】植物精油萃取自天然植物, 因具有抗菌活性, 近年来受到广泛关注。论文的目的是分析植物精油的化学成分, 测试其抗菌活性, 并研究其化学成分与抗菌活性之间的联系。【方法】实验选取了肉桂、山苍子、丁香、香茅、迷迭香和大蒜精油等6种典型植物精油, 通过气质联用分析方法研究了其化学组分, 并通过污染食物技术研究了其对黑曲霉和绳状青霉的抗真菌活性, 以及对大肠杆菌和金黄色葡萄球菌的抗细菌活性。【结果】气质联用分析结果表明, 肉桂、山苍子、香茅和迷迭香等4种植物精油的化学成分主要是醛类和醇类, 丁香精油的主要化学成分是丁香油酚, 大蒜精油化学成分基本上都是含硫的醚类, 其中二烯丙基三硫醚(大蒜素)含量最高。抗菌活性结果显示, 不同植物精油的抗菌活性不同, 6种植物精油的抗真菌活性由强到弱依次为: 肉桂>大蒜>丁香>山苍子=香茅>迷迭香, 抗细菌活性由强到弱依次为: 肉桂>山苍子>丁香>香茅=迷迭香>大蒜。【结论】植物精油的抗真菌、细菌活性与其化学组分密切相关, 肉桂、山苍子、香茅和迷迭香等4种精油的抗菌活性可能主要与其化学成分中的醛类和醇类有关, 丁香精油较高的抗菌活性可能主要源于丁香油酚; 大蒜精油具有高效的抗真菌活性主要源于其化学成分中的含硫醚。不同植物精油化学成分不同, 抗真菌、细菌活性也不同, 表明其可能有不同的抗真菌与抗细菌机制。     

Essential oil composition of five Artemisia (Compositae) species in regards to chemophenetics

In this work we analysed the essential oils (EO) obtained by hydrodistillation from the aerial parts of five Artemisia species (A. arborescens L., A. campestris L., A. lobelii All., A. annua L. and A. absinthium L.) originated from Serbia, Montenegro, and Libya, by gas chromatography coupled with mass spectrometry. In total, 126 compounds were detected, and 120 were identified. Even though a high number of compounds were detected, each individual sample had only 25 to 50, attesting to a great diversity of compounds between taxa. Depending on the species and the locality (geographical origin), EO was dominated by either monoterpenes or sesquiterpenes, with β-pinene, chamazulene, germacrene D, camphor, pinocarvone and thuja-2,4(10)-diene being the dominant compounds. The chemophenetic value of the EO compositions was discussed in relation to the results of the multivariate statistical test, including the detailed survey of the available literature data.     

Chemical composition and antimicrobial,antioxidant, and anti-inflammatory activities of Lepidium sativum seed oil

Lepidium sativum (garden cress) seed oil was examined for its antimicrobial, antioxidant, and anti-inflammatory activities. The oil was obtained by hydrodistillation, where gas chromatography coupled with mass spectrometry that utilized to study its chemical composition. Microdilution method was used to test the antimicrobial effect of oil against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica, Klebsiella pneumoniae, and Candida albicans. The antioxidant activity was assessed by radical scavenging activity assay using 2,2-diphenyl-1-picrylhydrazyl radical. The major constituents found in the oil were 7,10-hexadecadienoic acid, 11-octadecenoic acid, 7,10,13-hexadecatrienoic acid, and behenic acid. The minimum inhibitory concentration (MIC) against all pathogens was 47.5 mg/ml, except for Salmonella enterica, which showed MIC of 90 mg/ml. The oil demonstrated antioxidant activity in a dose dependent pattern, with a half maximal inhibitory concentration (IC₅₀) value of 40 mg/ml, and exerted anti-inflammatory activity, wherein 21% protection was shown at a concentration of 300 μg/ml. Thus, L. sativum seed oil shows antimicrobial, antioxidant, and anti-inflammatory properties.     

Evaluation of chemical composition and anti-inflammatory,antioxidant, antibacterial activity of essential oil of Sardinian Santolina corsica Jord. & Fourr.

Santolina corsica Jord. & Fourr. Corsican-Sardinian is an endemism almost present all around Corsica; in Sardinia, it can only be found in Monte Albo (calcareous substratum and poor in nutrients). The aim of our study is to investigate the chemical composition of S. corsica essential oils from plants growing in three different stations located at different altitudes and evaluate the biological activity using anti-inflammatory, antioxidant and antimicrobial test. The composition of the essential oils was determined by gas chromatography and gas chromatography/mass spectrometry. The essential oils of the Sardinian-Corsican endemism S. corsica, growing in Monte Albo, showed a great variability, probably due to genetic characters different from the Corsican type. We found three different chemotypes: artemisia ketone-β-fellendrene; myrcene and β-fellandrene-myrcene. Standard microbiological assays demonstrated that the essential oils collected in the selected stations, compared with oil and compound with demonstrated antibacterial activity, don’t have any antibacterial activity. DPPH test carried out on the tree samples, compared with chatechin, demonstrated that the oils don’t have antioxidant activity.Regarding anti-inflammatory activity the study demonstrated that the essential oils have a good anti-inflammatory activity on the bronchial tract.The addition of essential oil make easy the exocytose and the histiocytes can expel the anthracotic pigment into the culture medium, purifying its cytoplasm and restoring its ability to phagocytize more material. With a higher concentration of granulocytes in the sample, the incubation of cells shows a non-specific inflammatory pattern in which the addition of the essential oils has a positive impact on the decrease of granulocytes.More experiments are requested to confirm the data, but on the basis of these first results S. corsica essential oil showed potential activity against respiratory infections.     

Screening of chemical composition, antimicrobial and antioxidant activities of Artemisia essential oils

The chemical composition of essential oils isolated from aerial parts of seven wild sages from Western Canada – Artemisia absinthium L., Artemisia biennis Willd., Artemisia cana Pursh, Artemisia dracunculus L., Artemisia frigida Willd., Artemisia longifolia Nutt. and Artemisia ludoviciana Nutt., was investigated by GC–MS. A total of 110 components were identified accounting for 71.0–98.8% of the oil composition. High contents of 1,8-cineole (21.5–27.6%) and camphor (15.9–37.3%) were found in Artemisia cana, A. frigida, A. longifolia and A. ludoviciana oils. The oil of A. ludoviciana was also characterized by a high content of oxygenated sesquiterpenes with a 5-ethenyltetrahydro-5-methyl-2-furanyl moiety, of which davanone (11.5%) was the main component identified. A. absinthium oil was characterized by high amounts of myrcene (10.8%), trans-thujone (10.1%) and trans-sabinyl acetate (26.4%). A. biennis yielded an oil rich in (Z)-beta-ocimene (34.7%), (E)-beta-farnesene (40.0%) and the acetylenes (11.0%) (Z)- and (E)-en-yn-dicycloethers. A. dracunculus oil contained predominantly phenylpropanoids such as methyl chavicol (16.2%) and methyl eugenol (35.8%). Artemisia oils had inhibitory effects on the growth of bacteria (Escherichia coli, Staphylococcus aureus, and Staphylococcus epidermidis), yeasts (Candida albicans, Cryptococcus neoformans), dermatophytes (Trichophyton rubrum, Microsporum canis, and Microsporum gypseum), Fonsecaea pedrosoi and Aspergillus niger. A. biennis oil was the most active against dermatophytes, Cryptococcus neoformans, Fonsecaea pedrosoi and Aspergillus niger, and A. absinthium oil the most active against Staphylococcus strains. In addition, antioxidant (beta-carotene/linoleate model) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities were determined, and weak activities were found for these oils.     

Development of an LC/MS/MS Method for Simultaneous Detection of 11 Polyphenols in Rat Plasma and Its Pharmacokinetic Application after Oral Administration of Coreopsis tinctoria Extract

Eleven polyphenols, classified as flavonoid glycosides, flavonoid aglycones, and phenolic acids, are important bioactive components in the capitula of Coreopsis tinctoria (CCT). Nevertheless, their full pharmacokinetic profiles have not been demonstrated simultaneously. Therefore, a liquid chromatography – tandem mass spectrometry (LC/MS/MS) method was developed in the present work and used it to study the pharmacokinetics of these 11 compounds. We performed LC/MS/MS with a gradient mobile phase composed of water containing 0.1 % formic acid and acetonitrile containing 0.1 % formic acid on a Proshell 120 SB C18 column (2.1 mm×100 mm, 2.7 μm). We achieved a good chromatographic peak shape, resolution, and mass signal response, and multiple reaction monitoring facilitated the simultaneous detection of 11 analytes. In addition, we validated the selectivity, correlation coefficient, precision, extraction recovery, matrix effects, and stability of the LC/MS/MS method to be acceptable for 11 analytes in rat plasma. Subsequently, rats were orally administered with 50 % ethanol eluent of CCT (ECCT). Nine of 11 polyphenols were absorbed quickly (except for QCD and TCA), and their plasma levels peaked within 40 min. The exposure and C_max values of flavonoid glycosides and phenolic acids were lower than those of flavonoid aglycones. This is the first report to demonstrate the pharmacokinetics of 11 polyphenols in ECCT, which may play an important role in future studies of the bioactive components of ECCT and their bioactive mechanisms.     

Salvia verbenaca L. essential oil: Variation of yield and composition according to collection site and phenophase

The effect of the collection sites and phenophase on yield and chemical composition of Salvia verbenaca essential oils was evaluated. The essential oil constituents were assessed by gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS). The highest essential oil yields were observed for samples of the higher semi-arid bioclimate and at the flowering period. Eighty-five volatile constituents were identified and their percentages varied significantly (p < 0.05) depending on the collection site and the phenological stage. According to the plants origin, essential oils were dominated by monoterpene hydrocarbons, oxygenated monoterpenes and sesquiterpene hydrocarbons. The monoterpene hydrocarbons (31.9%) predominate at the flowering stage whereas oxygenated sesquiterpenes (27.5%) at the early fruiting stage. The sesquiterpene hydrocarbons (28.2%) was the most represented chemical class at late fruiting. On the basis of GC-MS data, the major identified volatile constituents were viridiflorol (3.4–17.7%), α-pinene (0.7–15.9%), β-caryophyllene (1.0–15.3%) and p-cymene (1.3–14.2%). S. verbenaca contains a diversity of bioactive constituents which shows large variations as affected by the collection sites and phenophase.