荆皮癣湿酊诱导红色毛癣菌凋亡的机制研究北大核心

【目的】本研究旨在探讨复方中药荆皮癣湿酊(Jingpixian tincture,JPXT)对红色毛癣菌(Trichophyton rubrum)的凋亡诱导作用,以阐明其可能的抗真菌作用机制。【方法】采用细胞计数试剂盒-8(cell counting kit-8,CCK-8)评价荆皮癣湿酊对红色毛癣菌生长活力的影响;流式细胞仪检测红色毛癣菌细胞内活性氧(reactive oxygen species,ROS)水平和线粒体膜电位(mitochondrial membrane potential,MMP)变化;Annexin V-FITC/PI染色荧光显微镜观察红色毛癣菌细胞磷脂酰丝氨酸(phosphatidylserine,PS)外翻情况;流式细胞术检测红色毛癣菌细胞凋亡率;FITC-VAD-FMK染色观察红色毛癣菌偏半胱天冬酶(metacaspase)活性;紫外分光光度计测定红色毛癣菌细胞色素C氧化酶的活性。【结果】荆皮癣湿酊处理后的红色毛癣菌细胞活力与MMP水平均有所降低,ROS水平显著升高,PS外翻与凋亡率明显增加,偏半胱天冬酶活性显著升高,细胞色素C氧化酶活性降低。【结论】荆皮癣湿酊可通过诱导菌体凋亡的方式发挥对红色毛癣菌的抗菌作用。     

皮肤癣菌体外蛋白水解酶活性测定

目的观察皮肤癣菌的体外蛋白水解酶活性;比较分离自不同感染部位的红色毛癣菌的体外蛋白水解酶活性。方法实验菌株包括来自不同感染部位的红色毛癣菌22株、须癣毛癣菌3株、犬小孢子菌5株,进行体外培养,并利用9-羟基乙酚噻唑标识的酪蛋白和酶标仪检测真菌细胞外蛋白水解酶的活性。结果须癣毛癣菌的体外蛋白水解酶活性高于红色毛癣菌和犬小孢子菌（P〈0.05）,而红色毛癣菌和犬小孢子菌之间无差异（P〉0.05）。红色毛癣菌的细胞外蛋白水解酶活性在分离自浅部感染部位的菌株之间无差异（P〉0.05）,但高于引起毛癣菌肉芽肿的菌株（P〈0.05）。结论不同的皮肤癣菌体外蛋白水解酶活性可能不同;分离自不同感染部位的同一菌种的体外蛋白水解酶活性也有可能不同。     

内生枯草芽孢杆菌SWB8 菌株β-1，3-1，4-葡聚糖酶的抗菌作用及细胞毒性

【目的】本文研究从药用植物黄姜中分离的内生枯草芽孢杆菌菌株SWB8分泌的β-1,3-1,4-葡聚糖酶的抗菌活性和细胞毒性。【方法】利用液体发酵、凝胶渗透色谱(GPC)、十二烷基-聚丙烯酰胺凝胶电泳(SDS-PAGE)和液相层析串联质谱(LC-MS/MS)等方法纯化和鉴定枯草芽孢杆菌株SWB8合成的β-1,3-1,4-葡聚糖酶;利用纸片扩散法,检测葡聚糖酶抑制临床致病性细菌和真菌生长的活性;应用MTT法和流式细胞术(FCM)评估此葡聚糖酶对人肺腺癌细胞(A549)和骨髓间质干细胞(MSCs)的细胞毒性。【结果】细菌性β-1,3-1,4-葡聚糖酶显示了广谱的抗菌活性;抗肿瘤活性主要以细胞凋亡的方式选择性的抑制人肺腺癌细胞系A549细胞的增殖,而对人骨髓间质干细胞系MSC细胞无明显影响。【结论】首次报道β-1,3-1,4-葡聚糖酶的抗菌和抗肿瘤细胞的活性。内生枯草芽孢杆菌SWB8菌株有可能成为抗菌和高效低毒的抗肿瘤药物的潜在来源。     

氧化应激在长脉宽1064nm Nd: YAG激光治疗甲真菌病中的作用

目的探讨长脉宽1064nm Nd:YAG激光对引起甲真菌病的最常见致病菌-红色毛癣菌(Trichophyton rubrum)的体外抑制/杀灭作用及活性氧簇(ROS)介导的氧化应激反应在其中发挥的作用。方法改变长脉宽1064nm Nd:YAG激光脉冲数(7次脉冲、9次脉冲、11次、13次脉冲),固定其他参数照射红色毛癣菌菌落,绘制生长曲线,确定有抑制作用的最小脉冲数。在此脉冲数条件下干预红色毛癣菌菌落及孢子悬液,比较菌落形态学改变,检测孢子悬液相对活力的改变,同时检测ROS在不同处理后的表达水平变化。结果激光对红色毛癣菌的抑制/杀灭作用随能量的增加而增强,相对活力随时间的增加而下降,呈能量和时间依赖性;激光干预后,菌丝失去正常形态结构,孢子悬液的荧光强度及ROS含量较未照射的高,P=0.0157。结论长脉宽1064nm Nd:YAG激光体外对红色毛癣菌有抑制/杀灭作用,ROS介导的氧化应激反应可能在该激光治疗红色毛癣菌甲真菌病中发挥了一定的作用。     

弗氏柠檬酸菌1,3-丙二醇合成的代谢工程研究

【目的】研究弗氏柠檬酸菌(Citrobacter freundii) 1,3-丙二醇合成的代谢过程。【方法】构建甘油脱氢酶基因GSR-lacZ、1,3-丙二醇氧化还原酶基因PDO-lacZ和甘油脱水酶基因GL-lacZ等报告基因。在此基础上,构建3个相应的转座子突变文库。【结果】筛选到6株突变子,其相应关键酶表达水平提高1?11倍,1,3-丙二醇产量提高幅度为3%?50%。对转座子插入位点分析显示,5株突变子插入位点均为β-内酰胺酶(CKO_02592)编码基因,1株突变子插入位点为二氢硫辛酰胺基转移酶(CKO_02433)编码基因。进一步分析发现,β-内酰胺酶基因突变显著提高甘油脱水酶和甘油脱氢酶的表达水平,而1,3-丙二醇氧化还原酶表达水平没有变化;二氢硫辛酰胺基转移酶基因突变显著提高1,3-丙二醇氧化还原酶表达水平,其他两种关键酶基因表达水平不变。【结论】β-内酰胺酶和二氢硫辛酰胺基转移酶基因能够分别影响1,3-丙二醇合成代谢途径关键酶的表达,为构建工程菌株打下基础。     

须癣毛癣菌的形态学及分子生物学鉴定

目的对临床上分离自人(36株)及狐狸(5株)的须癣毛癣菌菌株进行新的分类系统鉴定,并检测传统的分类方法是否能满足临床鉴定需要。方法①观察原鉴定为须癣毛癣菌菌株在沙氏培养基、1%蛋白胨培养基、溴甲酚紫乳固体葡萄糖琼脂培养基(BCP-MSG)和显微镜下形态学及尿素酶、毛发穿孔等生理学试验表现。②通过ITS区段和LSU区段分子生物学序列分析进行新的分类系统的菌种分型,并对传统形态学和生理学鉴定方法进行检测。结果①41株须癣毛癣菌形态学及生理学试验符合须癣毛癣菌(38株)和红色毛癣菌(3株)菌落的特点。②ITS区段序列分析发现ITS区段能将须癣毛癣菌和红色毛癣菌准确的鉴定到种,但无法明确其种内分型;而LSU区段序列分析可对36株(36/38)须癣毛癣菌有性型做出明确的鉴定。结论传统实验室鉴定方法仍具有其有效性及可靠性。通过分子生物学鉴定,临床分离的须癣毛癣菌皆为指(趾)间毛癣菌(38/38),而LSU区段的序列分析鉴定狐狸源性菌株皆属于本海姆节皮菌,有别于大多数人源性菌株有性型为万博节皮菌,对于须癣毛癣菌的菌种鉴定更优于ITS区段,但分子生物学试验还需结合形态学的观察,才能够对菌种做出正确的鉴定。     

参照CLSIM38-A方案测定皮肤癣菌临床株对4种抗真菌药物的敏感性

目的测定并比较临床分离的皮肤癣菌对4种常用抗真菌药物的敏感性,探讨CLSIM38-A方案用于皮肤癣菌药敏试验的可行性。方法实验菌株为31株临床近期分离的皮肤癣菌。其中红色毛癣菌14株,须癣毛癣菌14株,犬小孢子菌1株,铁锈色小孢子菌1株,絮状表皮癣菌1株。4种抗真菌药物为益康唑、伊曲康唑、特比萘芬、伏立康唑。采用M38-A方案微量稀释法,并适当调整试验参数进行体外抗真菌药物敏感性试验。结果红色毛癣菌和须癣毛癣菌对以上4种药物的敏感性无明显差异。犬小孢子菌、铁锈色小孢子菌、絮状表皮癣菌对所有4种抗真菌药物的敏感性都低于红色毛癣菌和须癣毛癣菌。结论M38-A方案经过调整适用于皮肤癣菌药敏试验。     

红色毛癣菌蛋白酶MEP和SUB的表达及临床意义

目的探讨红色毛癣菌蛋白酶MEP和SUB的表达及临床意义。方法抽提红色毛癣菌总RNA,采用半定量RTPCR法检测红色毛癣菌金属蛋白酶(Metalloproteinases,MEP)、枯草菌素蛋白酶(subtilisins,SUB)基因表达量的变化。结果不同病例的红色毛癣菌SUB的表达水平与临床症状的严重程度密切相关,而与患者的年龄、性别、病程等无明显相关性;MEP的表达水平在不同年龄、性别、病程和临床分型等方面存在一定差异,但无显著意义。结论红色毛癣菌致病力的大小可能与SUB的不同表达有关。     

枯草芽孢杆菌产β-1,3-1,4-葡聚糖酶的响应面优化

【目的】采用响应面法(RSM)优化枯草芽孢杆菌5 L发酵罐产β-1,3-1,4-葡聚糖酶的发酵条件。【方法】利用Box-Behnken设计和方差分析。【结果】获得最佳发酵条件为:转速、通气量和培养基pH分别为500 r/min、1.05 vvm和5.08,发酵时间仅为22 h产β-1,3-1,4-葡聚糖酶活力达2 294.4 U/mL。【结论】实验结果表明响应面法优化5 L发酵罐发酵产β-1,3-1,4-葡聚糖酶的条件合理可行。     

沙质微泡菌β-1,3(4)-葡聚糖酶的克隆表达及酶学性质

【背景】β-葡聚糖是自然界中广泛存在的非淀粉多糖,是谷类植物细胞壁的主要成分。β-葡聚糖酶能够水解β-葡聚糖生成低聚合度的寡糖,在食品、饲料、造纸等领域发挥着重要的作用。【目的】从海洋细菌沙质微泡菌(Microbulbifer arenaceous)中克隆到一个β-1,3(4)-葡聚糖酶基因,在大肠杆菌中可溶表达,研究其相关酶学性质。【方法】以沙质微泡菌(Microbulbifer arenaceous)基因组DNA为模板,克隆一个β-1,3(4)-葡聚糖酶基因(MaGlu16A),构建重组表达载体p ET-28a-MaGlu16A并在大肠杆菌BL21(DE3)中诱导表达,通过Ni-NTA亲和层析纯化后进行酶学性质研究。【结果】MaGlu16A的最适pH和最适温度分别为pH 6.0和40°C,在pH 5.0-10.5和35°C以下稳定。对EDTA具有较高的抵抗性,在1 mmol/L和10 mmol/L EDTA浓度下仍保持99.3%和82.5%的酶活力。该酶能够有效水解可得然多糖、昆布多糖、大麦葡聚糖、地衣多糖、燕麦葡聚糖和酵母葡聚糖,水解产物主要为葡萄糖、二糖、三糖和四糖。【结论】海...     

Foreign exploration for Scirtothrips perseae Nakahara (Thysanoptera: Thripidae) and associated natural enemies on avocado (Persea americana Miller)

Scirtothrips perseae Nakahara was discovered attacking avocados in California, USA, in 1996. Host plant surveys in California indicated that S. perseae has a highly restricted host range with larvae being found only on avocados, while adults were collected from 11 different plant species. As part of a management program for this pest, a “classical” biological control program was initiated and foreign exploration was conducted to delineate the home range of S. perseae, to survey for associated natural enemies and inventory other species of phytophagous thrips on avocados grown in Mexico, Guatemala, Costa Rica, the Dominican Republic, Trinidad, and Brazil. Foreign exploration efforts indicate that S. perseae occurs on avocados grown at high altitudes (>1500 m) from Uruapan in Mexico south to areas around Guatemala City in Guatemala. In Costa Rica, S. perseae is replaced by an undescribed congener as the dominant phytophagous thrips on avocados grown at high altitudes (>1300 m). No species of Scirtothrips were found on avocados in the Dominican Republic, Trinidad, or Brazil. In total, 2136 phytophagous thrips were collected and identified, representing over 47 identified species from at least 19 genera. The significance of these species records is discussed. Of collected material 4% were potential thrips biological control agents. Natural enemies were dominated by six genera of predatory thrips (Aeolothrips, Aleurodothrips, Franklinothrips, Leptothrips, Scolothrips, and Karnyothrips). One genus each of parasitoid (Ceranisus) and predatory mite (Balaustium) were found. Based on the results of our sampling techniques, prospects for the importation of thrips natural enemies for use in a “classical” biological control program in California against S. perseae are not promising.     

Phylogeny of cardinalfishes (Teleostei: Gobiiformes: Apogonidae) and the evolution of visceral bioluminescence

The cardinalfishes (Apogonidae) are a diverse clade of small, mostly reef-dwelling fishes, for which a variety of morphological data have not yielded a consistent phylogeny. We use DNA sequence to hypothesize phylogenetic relationships within Apogonidae and among apogonids and other acanthomorph families, to examine patterns of evolution including the distribution of a visceral bioluminescence system. In conformance with previous studies, Apogonidae is placed in a clade with Pempheridae, Kurtidae, Leiognathidae, and Gobioidei. The apogonid genus Pseudamia is recovered outside the remainder of the family, not as sister to the superficially similar genus Gymnapogon. Species sampled from the Caribbean and Western Atlantic (Phaeoptyx, Astrapogon, and some Apogon species) form a clade, as do the larger-bodied Glossamia and Cheilodipterus. Incidence of visceral bioluminescence is found scattered throughout the phylogeny, independently for each group in which it is present. Examination of the fine structure of the visceral bioluminescence system through histology shows that light organs exhibit a range of morphologies, with some composed of complex masses of tubules (Siphamia, Pempheris, Parapriacanthus) and others lacking tubules but containing chambers formed by folds of the visceral epithelium (Acropoma, Archamia, Jaydia, and Rhabdamia). Light organs in Siphamia, Acropoma, Pempheris and Parapriacanthus are distinct from but connected to the gut; those in Archamia, Jaydia, and Rhabdamia are simply portions of the intestinal tract, and are little differentiated from the surrounding tissues. The presence or absence of symbiotic luminescent bacteria does not correlate with light organ structure; the tubular light organs of Siphamia and chambered tubes of Acropoma house bacteria, those in Pempheridae and the other Apogonidae do not.     

Biological control of three floating water weeds,<Emphasis Type="Italic">Eichhornia crassipes,Pistia stratiotes</Emphasis>, and <Emphasis Type="Italic">Salviniamolesta</Emphasis> in the Republic of Congo

Since 1999, four specific weevils (Coleoptera, Curculionidae) were released in the Republic of Congo against three exotic floating water weeds: Neochetina eichhorniae Warner and N. bruchi Hustache against water hyacinth, Neohydronomus affinis Hustache against water lettuce, and Cyrtobagous salviniae Calder and Sands against water fern. Recoveries of exotic weevils were made from all 24 release sites except one, and all four species have established and spread (up to 800 km for water hyacinth weevils). Within a few years of releases, control of water fern and water lettuce was such that fishing and navigation could be resumed, while reductions of water hyacinth populations were only beginning.     

A molecular phylogeny of Hebeloma species from Europe

In order to widen the scope of existing phylogenies of the ectomycorrhizal agaric genus Hebeloma a total of 53 new rDNA ITS sequences from that genus was generated, augmented by sequences retrieved from GenBank, and analysed using Bayesian, strict consensus and neighbour joining methods. The lignicolous Hebelomina neerlandica, Gymnopilus penetrans, and two species of Galerina served as outgroup taxa. Anamika indica, as well as representatives of the genera Hymenogaster and Naucoria, were included to test the monophyly of Hebeloma, which is confirmed by the results. Hebeloma, Naucoria, Hymenogaster and Anamika indica cluster in a strongly supported monophyletic hebelomatoid clade. All trees largely reflect the current infrageneric classification within Hebeloma, and divide the genus into mostly well-supported monophyletic groups surrounding H. crustuliniforme, H. velutipes, H. sacchariolens, H. sinapizans, and H. radicosum, with H. sarcophyllum being shown at an independent position; however this is not well supported. The section Indusiata divides with strong support into three groups, the position of the pleurocystidiate Hebeloma cistophilum suggests the possible existence of a third subsection within sect. Indusiata. Subsection Sacchariolentia is raised to the rank of section.     

Taxonomic status of the species of the green algal genusNeochloris

Komárek has recently reviewed the various species assigned to the green algal genusNeochloris Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia. Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class.     

Die GattungKarschia — Bindeglied zwischen bitunicaten Ascomyceten und lecanoralen Flechtenpilzen?

The genusKarschia, in the earlier sense, including saprophytes and parasites on lichens, has been thought to be a non-lichenized parallel genus of the lichen genusBuellia. Modern workers included it on the one hand inBuellia, on the other hand combined it with bitunicate ascomycetes. It is now proved thatKarschia is heterogeneous and contains but superficially similar members both of the genusBuellia of theLecanorales and of typical or masked bitunicateAscomycetes. Therefore, it can not be regarded as a link betweenLecanorales andDothideales. The type species ofKarschia belongs to theDothideales.

     

Demographic characteristics of an intertidal bay goby (Lepidogobius lepidus)

Synopsis In a fourteen month study (May 1976 – June 1977) I examined the following characteristics of an intertidal bay goby (Lepidogobius lepidus) in Morro Bay, California, U.S.A.: annual and seasonal patterns of abundance, age composition and growth rates, survivorship and mortality patterns, and the reproductive cycle for female gobies. Fishes were collected with the aid of quinaldine and otoliths and ovaries removed. Age and growth rates were estimated from otolith annuli using a back calculation formula and a Brody-Bertalanffy growth curve. Mortality rates were derived using the methods of Heincke (1913), Robson & Chapman (1960), mean age, and a catch curve (Ricker 1975). A gonad index was used to describe the annual reproductive cycle. Results indicated that abundance fluctuated seasonally and that these fluctuations appeared to be caused by reproductive emigrations. Bay gobies reached an age of 7+ and a standard length of 87 mm. Growth was relatively constant (6 mm yr⁻¹) until age 5, at which point it began to decline. The mean rates of survivorship, mortality, and instantaneous mortality were 0.75, 0.25, and 0.29 respectively. Mortality rates for individual age classes ranged from 0.13 to 0.51 and increased with age. This stock appears to reproduce mainly during the winter.     

Systematic significance of mature embryo of bamboos

The mature embryo of seven species belonging to five genera of Indian bamboos is described. In all these the basic pattern of embryo organisation is same: the scutellar and coleoptilar bundles are not separated by an internode, the epiblast is absent, the lower portion of the scutellum and the coleorhiza are separated by a cleft and the margins of embryonic leaves overlap. The features unique to fleshy fruited bamboos are: presence of a massive scutellum, the juxtaposition of plumule and radicle and the occurrence of a bud in the axil of the coleoptile. The fleshy fruit bearing bamboos should be classified into one group, the tribeMelocanneae. Evidence is provided to recognise additional groups in the subfamilyBambusoideae.