黄芩苷联合氟康唑通过降低cAMP抑制白念珠菌酵母-菌丝形态转化

目的探讨中药有效成分黄芩苷(Baicalin,BA)联合氟康唑(Fluconazole,FLC)对白念珠菌(Candida albicans)形态转化的影响及机制。方法在菌丝诱导培养基(液体和固体培养基)上观察两药联用对白念珠菌酵母-菌丝形态转化的影响;ELISA法检测两药联用对胞内cAMP含量的影响;回补实验验证两药联用对胞内cAMP的影响;qRT-PCR检测两药联用对白念珠菌cAMP相关基因RAS1,CDC35和PDE2表达的影响。结果黄芩苷联合氟康唑能显著抑制白念珠菌酵母-菌丝形态转化,降低胞内cAMP水平;外源性cAMP能逆转两药联用所造成的菌丝抑制;两药联用使RAS1和CDC35表达分别下调35%和27%,使PDE2上调1.21倍。结论黄芩苷协同氟康唑显著抑制白念珠菌形态转化,其作用机制可能与下调胞内cAMP有关。     

黄芩素与氟康唑协同抗白念珠菌生物被膜作用研究

目的：研究黄芩素与氟康唑合用对白念珠菌生物被膜形成的影响。方法采用激光共聚焦显微镜观察黄芩素与氟康唑合用对白念珠菌生物被膜生长形态的影响;采用 XTT 法考察黄芩素与氟康唑合用对白念珠菌生物被膜形成能力的影响;应用水-烃两相测定实验考察黄芩素与氟康唑合用对白念珠菌生物被膜细胞表面疏水性（ Cell surface hydrophobicity, CSH）的影响;应用实时定量 RT-PCR（Real Time RT-PCR）实验考察黄芩素与氟康唑合用对白念珠菌 CSH1、EFG1、HWP1、ALS1基因表达的影响。结果黄芩素与氟康唑合用能够协同抑制白念珠菌生物被膜的形成,经黄芩素与氟康唑处理的白念珠菌不能形成正常的生物被膜,其生长动力学及细胞表面疏水性下降,细胞疏水性相关基 CSH1、菌丝形成调控基因EFG1、黏附相关基因 HWP1基因的表达水平降低。结论黄芩素与氟康唑合用可协同抑制白念珠菌生物被膜的形成。     

芒果苷协同氟康唑抗耐药白念珠菌作用研究

目的研究芒果苷与氟康唑合用对唑类耐药白念珠菌协同抗真菌的作用和机制。方法采用棋盘式微量稀释法测试芒果苷协同氟康唑对22株耐药白念珠菌的最小抑菌浓度MIC80;时间-杀菌曲线探究两药联用对4株耐药白念珠菌生长的抑制作用;药物生长抑制实验实验探究不同浓度芒果苷和不同浓度氟康唑协同抗耐药白念珠菌药效;通过实时定量RT-PCR检测两药联用时耐药基因CDR1、CDR2、MDR1表达水平。结果芒果苷联合氟康唑可产生协同抗唑类白念珠菌作用,协同指数(FICI)0.5;两药合用对白念珠菌生长可产生抑制作用;两药合用降低耐药基因CDR1表达水平。结论芒果苷与氟康唑合用可产生协同抗唑类耐药白念珠菌作用。     

CRK1基因缺失对白念珠菌形态、黏附、生物被膜的影响

目的 研究CRK1基因缺失对白念珠菌形态、黏附、生物被膜的影响.方法 显微镜下观察,计算菌丝形成率,比较CRK1基因缺失菌（Δcrk1菌）及标准菌SC5314形成菌丝的能力;建立肠黏膜模型,计算黏附率,评价CRK1基因缺失对白念珠菌黏附的影响;MTT法及结晶紫法（CV）评价CRK1基因缺失对白念珠菌生物被膜形成的影响.结果 与SC5314相比,Δcrk1菌分别在10％胎牛血清和RPMI-1640培养条件下形成菌丝能力均较弱,两者之间有统计学差异;Δcrk1菌在60、90、120 min时对肠黏膜的黏附数明显少于标准菌SC5314,两者之间有统计学差异;通过MTT法、结晶紫法两种方法证实了,在经48 h培养后,Δcrk1菌与其标准菌SC5314相比,形成生物膜的能力弱,两者之间差异有统计学差异.结论 CRK 1基因缺失影响白念珠菌菌丝二态性的转化,进而影响黏附力和生物被膜的形成.     

利福喷丁对氟康唑体外抗耐药白念珠菌的增效作用

目的测定利福喷丁(Rifapentine)对氟康唑(Fluconazole)体外抗耐药白念珠菌的增效作用。方法参考美国临床实验室标准化委员会(CLSI)的M27-A2方案测定利福喷丁与氟康唑对白念珠菌的最低抑菌浓度(MIC);利用棋盘式微量液基稀释法测定利福喷丁联合氟康唑体外抗白念珠菌的效果。结果利福喷丁单药时对实验所用12株白念珠菌均无抗菌活性(MIC801 024μg/mL)。在氟康唑敏感白念珠菌株中,利福喷丁联合氟康唑后未表现出协同效应(FICI0.5);在氟康唑耐药白念珠菌中,利福喷丁联合氟康唑后均表现出显著的协同作用(FICI0.1)。结论利福喷丁单用无抗白念珠菌活性,但利福喷丁能显著增强氟康唑抗耐氟康唑白念珠菌活性。     

汉防己甲素及其联合氟康唑对白念珠菌细胞周期影响的初步研究

目的 探讨汉防己甲素联合氟康唑对白念珠菌细胞周期的影响.方法 将白念珠菌CA-1菌悬液与汉防己甲素和（或）氟康唑共培养12h,应用流式细胞仪测定空白对照组、汉防己甲素组、氟康唑组及汉防己甲素联合氟康唑组DNA含量.比较细胞周期各期DNA含量变化并计算增殖抑制率PI％,分析汉防己甲素及其联合氟康唑对白念珠菌细胞周期的影响.结果 汉防己甲素、氟康唑组与对照组S期DNA含量相比,分别能增加17.25％ （P =0.018）与6.54％ （P ＞0.05）,其联合运用效果更明显,S期DNA含量可增加31.52％ （P =0.002）.这说明汉防己甲素能将白念珠菌细胞阻滞在S期.结论 汉防己甲素能抑制白念珠菌细胞DNA合成,阻断白念珠菌细胞周期进程,抑制细胞分裂,其与氟康唑联用时阻滞作用更显著.     

胡桃楸提取物对体外白念珠菌生物膜形成的影响

目的研究胡桃楸提取物对白念珠菌生物膜形成的影响。方法采用甲基四氮盐（XTT）还原法评价胡桃楸提取物对白念珠菌的生物膜形成及黏附性的影响。镜下观察胡桃楸提取物对白念珠菌生物膜的形态学影响。结果胡桃楸提取物抑制白念珠菌生物膜50％及90％的最小抑制药物浓度（SMIC50、SMIC90）分别为15．2μg、23．4μg。胡桃楸提取物作用浓度大于20μg时对该菌细胞黏附有抑制作用。30μg胡桃楸提取物可完全抑制白念珠菌生物膜的形成。结论胡桃楸提取物对体外白念珠菌生物的膜形成有较强的抑制作用。     

牡丹皮水煎剂对体外白念珠菌生物膜的抑制作用

研究牡丹皮水煎剂对体外白念珠菌生物膜的影响。体外构建白念珠菌生物膜并采用XTT减低法评价牡丹皮水煎剂对白念珠菌成熟生物膜影响以及包被生物材料对白念珠菌生物膜形成的影响。结果显示,牡丹皮水煎荆对白念珠菌悬浮菌MIC为1．56mg／mL;对白念珠菌生物膜SMIC50与SMIC50分别是3．12和6．25mg／mL;药物包被96孔板对白念珠菌生物膜形成有一定的抑制效应。实验表明牡丹皮水煎剂对体外白念珠菌生物膜有较强抑制作用。     

28种药物联合氟康唑对白念珠菌体外抑菌作用的初步研究

目的 从常用免疫抑制剂、降血脂药、抗抑郁药、抗生素及非甾体类抗炎药中筛选出可能与氟康唑具有协同增效作用的药物.方法 将5类28种药物配制成相同浓度（100 μg/mL）后分别单独及与低浓度氟康唑联合加入白念珠菌耐药菌株（l00、103）及敏感菌株（sc5314、y0109）菌悬液中,24 h（敏感菌）及48 h（耐药菌）后观察菌液澄清情况,菌液完全澄清为“＋”,混浊为“-”,并重复上述实验3次.结果 舍曲林等7种药物在该浓度下单用即可抑制所有实验菌株生长,与氟康唑合用后抑菌作用更加显著;利福喷丁等6种药物在该浓度下单用只能抑制敏感菌株生长,但与低浓度氟康唑合用后对耐药菌株也有抑制作用.结论 舍曲林、利福喷丁等药物与氟康唑联合后对白念珠菌可能具有协同抑制作用.     

氟尼辛葡甲胺对克柔念珠菌生物膜形成的影响及联合唑类药物效果评价

目的本研究旨在评价氟尼辛葡甲胺(FM)对克柔念珠菌生物膜形成的抑制作用以及和唑类药物联用对克柔念珠菌的体外抗菌作用。方法以患真菌性乳房炎奶牛奶样临床分离克柔念珠菌为试验菌株,采用微量稀释法测定最小抑菌浓度(MIC)、最小杀菌浓度(MFC)初步探讨FM对克柔念珠菌的抑菌活性。水-烃两相法测定细胞表面疏水性(CSH)并通过XTT法测定FM对克柔念珠菌生物膜形成早期1～3 h黏附阶段的影响以及培养24 h后成熟生物膜的影响;以部分抑菌浓度指数(FICI)作为检测指标,通过棋盘法检测与唑类药物联用对克柔念珠菌体外静态抗菌作用;采用酶标比浊法测定绘制不同药物处理后的时间-抑菌曲线。结果 FM单药对克柔念珠菌的MIC均为0.625 mg/mL;FM可以降低CSH,对不同生长阶段(早期黏附、成熟)的克柔念珠菌生物膜均有显著抑制作用,抑制作用具有时间和浓度依赖性;联合用药发现,FM与伊曲康唑联用抗克柔念珠菌的FICI介于0.5～1.5之间,表现为协同/相加作用;与酮康唑联合用药的FICI指数介于0.375～1.25之间,表现为协同/相加作用;与氟康唑联用则表现为无关;时间-抑菌曲线显示,部分唑类药物与FM联用能增强其对克柔念珠菌抑制作用,并维持较长的作用时间。结论 FM是一种有效的抗真菌增效剂,可以促进伊曲康唑和酮康唑的抗真菌活性。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.