实验性变态反应性脑脊髓炎大鼠发病中脑组织血红素氧合酶-1基因和蛋白表达的动态变化

为探讨脑组织血红素氧合酶-1(hemeoxygenase-1,HO-1)对实验性变态反应性脑脊髓炎(experimental allergic encephalomyelitis,EAE)的作用,分别应用逆转录-聚合酶链反应(RT-PCR)和免疫组化技术测定了豚鼠脊髓生理盐水匀浆 完全福氏佐剂诱导EAE大鼠1、7、14、21d时,脑组织HO-1基因和蛋白表达的动态变化,并观察与症状之间的关系。结果显示：对照组大鼠脑组织仅有少量HO-1基因和蛋白表达：诱导EAE后,伴随着大鼠EAE症状及脑组织病理损伤的出现和进行性加重,脑组织HO-1基因和蛋白表达量逐渐增高。在豚鼠脊髓生理盐水匀浆 完全福氏佐剂诱导7d后,HO-1 mRNA上升至高峰。14d时,HO-1蛋白表达至高峰,HO-1阳性细胞主要位于脉络丛、穹隆下器、血管“套袖样”病灶的周围,与EAE病变部位一致。此时大鼠的病情最重、体重减轻最显著、脑组织病理改变最明显。21d时脑组织HO-1基因和蛋白表达量逐渐下降,大鼠EAE症状也逐渐减轻。应用HO-1特异性抑制剂锡原卟啉-9以抑制脑内HO-1蛋白表达后,大鼠EAE症状和脑组织损伤明显减轻,说明脑组织HO-1的动态变化与EAE症状及脑组织损伤密切相关。提示脑组织HO-1基因和蛋白过表达对EAE发病起着重要的作用,应用HO-1抑制剂可能是防治该病的有效方法之一。     

脑组织核因子-κB激活对实验性变态反应性脑脊髓炎的作用

为探讨脑组织核因子－κB（NF－κB）对实验性变态反应性脑脊髓炎（EAE）的作用,分别用凝胶电泳迁移分析和NF－κB p65免疫组化方法测定了CFA－GPSCH诱导大鼠EAE1、7、14和21d时脑组织NF－κB活性和蛋白表达的动态变化,并观察了这些变化与EAE症状之间的关系。结果表明;对照组大鼠脑组织仅有少量NF－κB蛋白表达,其活性也很低;诱导EAE后,伴随着大鼠EAE症状及脑组织病理损伤的出现和进行性加重,其NF－κB活性和蛋白表达量逐渐增高;在免疫后14d达到高峰,NF－κB阳性细胞主要位于脉络丛、穹隆下器、血管“套袖样”病灶的周围,与EAE病变部位一致,此时大鼠EAE发病率最高、病情最重、体重减轻最显著、脑组织病理改变也最明显;21h脑组织NF－κB活性和蛋白表达量逐渐下降,大鼠EAE症状也逐渐恢复。应用NF－κB特异性抑制剂PDTC以抑制脑内组织NF－κB活性和蛋白表达量逐渐下降,大鼠EAE症状也逐渐恢复。应用NF－κB特异性抑制剂PDTC以抑制脑内NF－κB蛋白表达后,大鼠EAE症状和脑组织损伤明显减轻,说明脑组织NF－κB的动态变化与EAE症状及脑组织损伤程度密切相关。结论：脑组织NF－κB的激活对EAE的发病起着关键的作用,应用NF－κB抑制剂可能是防治该病的有效方法之一。     

核因子-κB在脂多糖诱导大鼠心肌血红素加氧酶-1基因表达中的作用

目的：观察核因子-κB（NF-κB）在脂多糖（LPS）诱导大鼠心肌血红素加氧酶-1（HO-1）表达中的作用,探讨其对内毒素休克（ES）的影响。方法：用生理多导仪监测大鼠静脉注射LPS（8mg／Kg）后12h平均动脉压（MAP）变化：用免疫组化方法检测心肌组织NF-κBp65和HO-1蛋白表达的变化;用逆转录多聚酶链反应（RT-PCR）检测心肌组织HO-1基因表达的变化。结果：①LPS组MAP较对照组快速持续降低（P〈0．01）：②LPS可诱导大鼠心肌间质血管内皮细胞和心肌细胞NF-κB阳性表达增强,1／2h和2h表达明显升高,6h和12h逐渐降低;③LPS可诱导大鼠心肌HO-1基因表达上调,2h开始增加,6h达到高峰,12h表达下调;LPS组大鼠心肌间质血管内皮细胞和心肌细胞HO-1蛋白表达在6h明显增强,12h表达减弱。④应用PDTC可明显减轻ES大鼠心肌损伤,并抑制心肌HO-1蛋白和基因表达。结论：LPS活化的心肌NF-κB参与LPS诱导心肌HO-1蛋白和基因高表达的信号转导,可能是导致ES顽固性低血压的机制之一。     

高压氧对TBI大鼠脑组织中氧化因子表达情况和Nrf2通路的影响

目的：研究高压氧（Hyperbaric oxygen,HBO）治疗对创伤性脑损伤（Traumatic brain injury,TBI）大鼠脑组织中氧化因子表达和核因子E2相关因子2(NF-E2-related factor 2,Nrf2)/血红素氧合酶（Heme oxygenase-1,HO-1）信号通路的影响。方法：将72只雄性SD大鼠随机分为假手术组（SHAM组）、创伤性脑损伤组（TBI组）、高压氧治疗组（HBO组）,每组24只;再按TBI造模后3天、7天将每组大鼠分为3d、7d两个亚组,每个亚组12只。分别于实验第3 d、7 d对各组大鼠进行改良神经损伤严重程度评分（Modified neurological severity score,m NSS）;使用酶活试剂盒检测脑组织中超氧化物歧化酶（Superoxide dismutase,SOD）、丙二醛（Malondialdehyde,MDA）、过氧化氢酶（Catalase,CAT）表达水平;Western blot法检测脑组织中Nrf2、HO-1蛋白的表达水平。结果：TBI组、HBO组大鼠神经功能在实验后3 d、7 d均较SH...     

刺激大鼠穹窿下器官诱发饮水和脑内c—fos表达的胆碱能机制

实验以饮水行为脑内c-fos表达为指标,,观察刺激大鼠穹窿下器官（SFO）的效应,结果显示,刺激SFO能诱发明显的饮水行为,与此同时,前脑8个部位（终板血管器官,正中视前核,室旁核,视上核,下丘脑外侧区,穹窿周核背侧区,丘脑联合核和无名质）和后脑3个部位（最后区,孤束核和壁旁外侧核）的Fos蛋白表达明显增强,免疫组化双重染色结果显示,刺激SFO能诱导视上核和室旁核中部分神经元呈Fos蛋白和加压素共同表达。脑室注射阿托品能部分阻断刺激SFO诱发的饮水行为,脑内上述各部位所诱导的Fos蛋白表达也明显减弱,以上结果提示,M胆碱能机制参与 刺激SFO诱发的饮水行为和脑内Fos蛋白的表达。     

切除肾上腺对大鼠自身免疫性脑脊髓炎敏感性的影响

目的研究肾上腺切除导致下丘脑-垂体-肾上腺(HPA)轴功能缺陷对Wistar大鼠诱发的实验性自身免疫性脑脊髓炎(EAE)的敏感性的影响。方法 Wistar大鼠单、双侧肾上腺切除后,用GPSCH-CFA诱导各组大鼠产生EAE,并观察临床评分、MBP抗体、皮质醇、Th1细胞因子和脑组织Bcl-2/Bax蛋白表达的变化,并与Lewis大鼠的EAE模型进行比较。结果 GPSCH-CFA诱导后,双侧切除肾上腺的Wistar大鼠平均神经症状评分最高为4.60分,发病率为100%,血清中皮质醇水平明显降低和MBP抗体水平明显升高,IFN-γ、TNF-α和IL-2水平均明显升高,大脑皮层和下丘脑中Bcl-2蛋白表达均明显降低和Bax蛋白表达均明显升高。结论双侧肾上腺切除导致HPA功能缺陷能显著增加Wistar大鼠诱发EAE的敏感性。     

SD大鼠和Wistar大鼠实验性自身免疫性脑脊髓炎发病情况比较

目的比较Wistar大鼠和Sprague-Dawley（SD）大鼠实验性自身免疫性脑脊髓炎（EAE）发病情况。方法注射以豚鼠脊髓匀浆-完全福氏佐剂制备的完全抗原,辅以百日咳疫苗加强诱导,复制Wistar大鼠和SD大鼠EAE模型,比较两组大鼠EAE的神经症状及中枢神经不同部位病理学改变。结果Wistar大鼠组发病数、潜伏期、发病达峰时间以及神经症状最高评分分别为9/12、12.33±1.37、15.17±3.19、1.33±0.41;SD大鼠组分别为11/12、15.88±0.64、18.63±1.52、3.13±1.89;两组大鼠相比,SD大鼠EAE潜伏期延长（P〈0.01）,达峰时间相应推迟（P〈0.05）,但神经症状较Wistar大鼠严重（P〈0.05）;病理结果显示,两组大鼠CNS均以脑干病理改变最为严重,而大脑病变最轻,SD大鼠总体中枢系统炎症改变较Wistar大鼠严重（标准评分P〈0.01,血管套计数P〈0.05）。结论SD大鼠EAE与Wistar大鼠EAE比较,发病过程很相似：发病率接近,中枢炎症病理改变相仿,两者均以脑干炎症变化最严重;略有不同点是：SD大鼠EAE发病潜伏期较长（P〈0.01）,神经症状较严重（P〈0.05）,总体中枢炎症改变较为严重。故SD大鼠也是制备EAE模型的理想实验动物。     

转染人血红素加氧酶-1基因对大鼠血管平滑肌细胞抗氧化损伤的作用

本实验构建含人血红素加氧酶-1（hHO-1)基因的逆转录病毒载体XM-6/hHO-1,将其导入离体培养的大鼠血管平滑肌细胞（vascular smooth muscle cells,VSMC),观察外源性hHO-1基因在VSMC内的表达及其抗活性氧损伤作用,结果表明：（1）hHO-1基因可在靶细胞中明显表达,转染VSMC的HO-1蛋白表达和HO酶活性分别比非转染细胞高1.8倍和2.0倍;（2）转染hHO-1的VSMC可对抗大剂量H2O2对细胞的损伤作用,表现为细胞存活率增加和乳酸脱氢酶（LDH）漏出减少,上述保护作用可被HO特异性抑制剂锌原卟啉IX（Zinc-proto-porphyrinIX,ZnPP-IX)所阻断,研究结果提示,外源性HO-1的过量表达可增加VSMC对抗氧化损伤的能力。     

原子力显微镜检测过表达α-突触核蛋白引起的线粒体结构变化

目的：利用原子力显微镜等方法,明确α-突触核蛋白（α-synuclein, α-syn）过表达对线粒体的影响。方法：将腺相关病毒（AAV）载体介导表达的α-syn (AAV /α-syn)病毒包装颗粒,给大鼠脑内黑质区定位注射,建立α-syn过表达的大鼠模型,并以AAV介导表达的报告基因LacZ (AAV/LacZ)为动物对照组。提取大鼠黑质脑组织的线粒体,并通过JC1染色检测线粒体膜电势（ΔΨ）变化和Western Blot检测线粒体中α-syn蛋白量的变化;采用原子力显微镜观测线粒体表面结构的变化。结果：实验组大鼠黑质脑组织过表达α-syn基因,第16周时,Western blot显示线粒体中α-syn蛋白量增加约2倍;JC1染色发现ΔΨ下降;原子力显微镜观测可见线粒体体积增大,线粒体膜表面出现较多孔道样改变。结论：大鼠黑质脑组织过表达α-syn基因,第16周时,可导致α-syn蛋白在线粒体积聚;并可引起线粒体增大、膜形成孔道样改变、ΔΨ下降。     

血红素加氧酶-1对肝癌细胞细胞周期调控因子的影响

目的观察血红素加氧酶-1（heme oxygenase 1,HO-1）对人肝癌细胞HepG2细胞周期调控因子的影响。方法构建含有野生型和突变型HO-1基因的重组载体pcDNA3．1（＋）-wtHO-1和pcDNA3．1（＋）-mHO-1G143H。利用脂质体介导的方法将构建好的重组载体转染肝癌细胞系HepG2,以空载体转染作为对照组。通过G418筛选建立稳定表达野生型和突变型HO-1的HepG2肝癌细胞系。经半定量RT—PCR、Western印迹检测转染细胞系中HO-1 mRNA和蛋白的表达水平。在HO-1表达改变的稳转细胞系中,利用Western印迹检测转染细胞系中P21、P27蛋白表达水平。结果成功实现了野生型和突变型HO-1在HepG2细胞中的过表达;野生型和突变型HO-1过表达均能诱导抑癌基因p21和p27的表达。结论HO．1过表达诱导抑癌基因p21和p27的表达与血红素分解产物无关。HO-1可能通过其它机制调节p21和p27的表达。     

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.