马桑内酯激活的星形胶质细胞条件培养液对正常大鼠脑内及培养的神经元内PLCβ1的影响

目的揭示星形胶质细胞对大鼠脑内及培养的神经元磷脂酶Cβ1(PLCβ1)的影响及其在癫痫发病中的作用。方法将马桑内酯激活的星形胶质细胞条件培养液(astrocyte-conditioned medium,ACM)注射入正常SD大鼠侧脑室,观察大鼠的行为变化;运用免疫组织化学方法,观察大鼠大脑皮质、海马内PLCβ1免疫反应的变化;将培养的神经元随机分为2组:1.对照组(无血清培养基组),2.ACM组。各组细胞分别培养4、8、12h后,免疫细胞化学方法观察培养神经元内PLCβ1表达的变化,Western blot法检测各组培养神经元PLCβ1含量的变化。结果ACM组大鼠在注射ACM后30 min出现癫痫行为,2 h恢复正常;免疫组织化学显示:ACM作用后4h,大鼠大脑皮质、海马PLCβ1免疫反应阳性神经元数和平均光密度值显著增高(P<0.05);培养神经元的免疫细胞化学染色证明ACM组在作用4h时PLCβ1免疫阳性反应产物明显增加,与对照组比较有明显差异(P<0.05);Western blot结果表明PLCβ1含量在ACM作用4h较对照组明显增多(P<0.05)。结论马桑内酯激活的星形胶质细胞条件培养液可上调大鼠脑内及培养的神经元内PLCβ1的表达,并导致动物痫性发作。     

马桑内酯激活的星形胶质细胞条件培养液对正常大鼠脑内谷氨酸和GABA的影响

目的探讨星形胶质细胞对大鼠脑内谷氨酸(Glu)和γ-氨基丁酸(GABA)的影响及其在癫痫发病中的作用。方法将马桑内酯激活的星形胶质细胞条件培养液(astrocyte-conditioned medium,ACM)注射入正常SD大鼠侧脑室,观察大鼠的行为变化,运用免疫组织化学及HPLC的方法,观察大鼠大脑皮质、海马内Glu和GABA免疫反应的变化及脑组织匀浆、脑脊液内Glu和GABA含量的变化。结果ACM组大鼠在注射ACM后30min出现癫痫行为,2h恢复正常。免疫组织化学显示:ACM作用后2h,大鼠大脑皮质及海马内Glu免疫反应阳性神经元数和平均光密度值明显增高,4h达高峰(P<0.05),12h恢复正常水平;ACM作用后2h,大鼠大脑皮质及海马GABA免疫反应阳性神经元数和平均光密度值明显减弱(P<0.05),12h恢复正常水平。HPLC方法显示:ACM作用后2h大鼠大脑皮质、海马及脑脊液中Glu含量均开始增加,4h达高峰(P<0.05);ACM作用后2h大脑皮质、海马及脑脊液中GABA含量均开始降低,4h达最低(P<0.05)。结论马桑内酯激活的星形胶质细胞条件培养液可影响大鼠脑内Glu和GABA的表达,并导致动物痫性发作。     

HLRP 蛋白在大鼠脑中的定位及LPS 对其表达的影响

目的:研究HLRP分子在大鼠脑中的细胞定位和表达特点,观察LPS刺激对动物脑HLRP表达的影响。方法:对原代培养的大鼠神经元、星形胶质细胞、小胶质细胞和大鼠脑组织冰冻切片分别进行免疫荧光染色,观察HLRP的细胞定位和表达特点;给大鼠侧脑室注射LPS,提脑组织蛋白,进行Western blot检测,半定量分析LPS刺激后,大鼠脑HLRP的表达变化。结果:①HLRP选择性表达于部分神经元的细胞核中,正常的星形胶质细胞和小胶质细胞不表达HLRP。②从嗅脑到脑干各节段,HLRP在大鼠脑组织中均匀分布,未发现HLRP阳性神经元聚集的现象。③侧脑室注射LPS 1天以后,HLRP表达明显升高(P<0.05)。结论:大鼠脑中正常表达HLRP,侧脑室注射LPS能刺激HLRP表达。     

鱼藤酮帕金森大鼠多脑区铁积聚与胶质细胞激活

目的观察鱼藤酮帕金森病（Parkinson＇s disease,PD）大鼠铁积聚脑区胶质细胞是否激活。方法雄性Wistar大鼠予颈背部皮下注射鱼藤酮（2 mg/kg）葵花油乳化液,每日一次,连续注射4~6周制备PD模型,8周时做冰冻切片,行免疫组化染色观察PD大鼠铁积聚脑区小胶质细胞（OX42）和星形胶质细胞（GFAP）。结果 PD大鼠黑质致密部、海马齿状回颗粒细胞层、纹状体苍白球、小脑齿状-间位核及小脑面神经核中铁染色显著积聚区域内小胶质细胞和星形胶质细胞染色积分光密度值较正常组明显增加（P〈0.05）。结论鱼藤酮PD大鼠铁积聚脑区小胶质细胞、星型胶质细胞均呈激活状态。     

蝎源活性肽对早期帕金森病大鼠脑源性营养因子及神经肽Y的影响

目的：研究蝎源活性肽对早期帕金森病（PD）大鼠脑源性营养因子（BDNF）及神经肽Y （NPY）的影响。方法：实验动物随机分为三组（n=11）,分为早期PD模型组、假手术对照组和蝎源活性肽治疗组。将6羟多巴（6-OHDA,20μg/3μl含0.1%抗坏血酸生理盐水）注射到SD大鼠右侧纹状体制备早期PD模型,注射2周后,通过旋转行为学检测造模是否成功;造模成功的早期PD大鼠,和相应的对照组腹腔注射蝎源活性肽（2.20 mg/kg·d）处理1周。3周后,用免疫组织化学法检测大鼠脑源性营养因子及神经肽Y的免疫反应活性。结果：在6-OHDA给药侧,PD动物与假手术对照组相比较,BDNF免疫反应活性明显增强,NPY免疫反应活性明显减少,蝎源活性肽处理可以逆转这些异常改变。结论：改变PD早期中脑内NPY与BDNF的免疫反应活性是蝎源活性肽对早期PD大鼠中脑多巴胺能神经元的保护作用机制之一。     

马桑内酯激活的星形胶质细胞条件培养液对正常大鼠脑内孕激素及其受体的影响

目的探讨星形胶质细胞对大鼠脑内孕激素及其受体的影响以及在癫痫发病中的作用。方法将马桑内酯(Coriaria lactone,CL)激活的星形胶质细胞条件培养液(Astrocytic conditioned medium,ACM)注射入正常SD大鼠侧脑室后,观察大鼠的行为变化;运用免疫组织化学方法观察大脑皮质及海马中孕激素受体(PR)表达的变化;运用放射免疫分析方法,观察脑组织匀浆及脑脊液内孕酮含量的变化。结果ACM组大鼠在注射ACM后30min出现癫痫行为,2h恢复正常;免疫组织化学显示:ACM作用后2h,PR免疫反应阳性神经元数和平均光密度值明显降低,4h达最低(P<0.05),12h恢复正常水平;放射免疫分析方法显示ACM组大鼠在侧脑室注射ACM后2h,脑脊液中孕酮含量明显升高;而海马组织和大脑皮质中孕酮含量则在注药后4h明显降低,与对照组比较均有显著差异(P<0.05)。结论以上实验结果提示马桑内酯激活的星形胶质细胞条件培养液可通过降低大鼠脑内孕激素及其受体的表达参与癫痫的反复发作。     

马桑内酯激活的星形胶质细胞条件培养液对正常大鼠脑内TNF-α的影响

目的揭示激活的星形胶质细胞条件培养液对正常大鼠脑内TNF-α的影响.方法将马桑内酯(coriaria lactone,CL)激活的星形胶质细胞条件培养液(astrocytic conditioned medium, ACM)注射入正常SD大鼠侧脑室,观察大鼠的行为变化,运用免疫组织化学及放射免疫分析的方法,观察脑组织匀浆及脑脊液内肿瘤坏死因子(TNF-α)含量的变化.结果ACM组大鼠在注射ACM 30min后出现癫痫行为,2h后恢复正常;免疫组织化学显示: ACM作用后2h,TNF-α免疫反应阳性神经元数和平均光密度值明显增高,4h达高峰(P<0.05),12h恢复正常水平;放射免疫分析方法显示ACM作用后2h大鼠大脑皮质、海马及脑脊液中TNF-α含量均开始增加,4h达高峰(P<0.05).结论以上实验结果提示马桑内酯激活的星形胶质细胞条件培养液可增强大鼠TNF-α的表达,并与癫痫发病有关.     

甘珀酸对内脏痛大鼠延髓星形胶质细胞和神经元反应的影响

目的:研究侧脑室注射甘珀酸后对福尔马林灌胃致内脏疼痛大鼠的延髓迷走孤束复合体内星形胶质细胞和神经元反应的影响.方法:经侧脑室注射缝隙连接阻断剂甘珀酸(carbenoxolone,CBX)后向大鼠胃内灌入2.5%福尔马林2ml诱发内脏疼痛,用免疫组织化学方法观察延髓迷走孤束复合体(VSC)内抗Fos蛋白(标记神经元)和抗胶质原纤维酸性蛋白(标记星形胶质细胞)的单一或双重标记的免疫荧光染色.结果:福尔马林灌胃后大鼠出现烦躁易激惹,呼吸变快,持续1h;而预先侧脑室注射CBX则动物疼痛行为学反应明显减轻.免疫组织化学染色发现福尔马林灌胃后大鼠VSC中的Fos免疫反应数目增强;大鼠预先侧脑室注射CBX后VSC中的Fos免疫反应数目明显减弱.结论:延髓VSC中的星形胶质细胞和神经元参与福尔马林灌胃致内脏痛的调节,星形胶质细胞可能通过缝隙连接影响神经元对内脏痛的调节功能.     

高压氧对急性CO 中毒大鼠脑内源性神经干细胞的影响

目的:探讨高压氧对急性CO中毒大鼠脑内源性神经干细胞的影响,分析HBO治疗急性CO中毒脑损伤的机制。方法:建立急性CO中毒大鼠模型,给予高压氧(HBO)治疗后,H-E染色观察大鼠脑组织病理学变化,免疫组织化学方法检测大鼠脑内神经干细胞(nestin)和星形胶质细胞(GFAP)的表达。结果:H-E染色标本上,对照组脑内神经元形态正常,染毒组脑皮质出现大量变性坏死细胞,海马锥体细胞层稀疏,HBO组坏死细胞明显减少。免疫组化结果显示对照组nestin和GFAP表达数量形态均正常,染毒组nestin表达增加,但无统计学意义,GFAP形态数量发生改变,HBO组nestin表达明显增加,且在大脑皮层可见部分nestin阳性细胞和nestin-GFAP双阳性细胞;GFAP表达趋于正常。结论:急性CO中毒作为脑损伤因素可轻度激活大鼠脑内源性神经干细胞,并使星形胶质细胞增生变形、神经元变性坏死,HBO治疗可减轻星形胶质细胞损伤,明显激活内源性神经干细胞,并促使其增殖、迁移和分化。提示HBO可能通过激活神经干细胞起治疗作用。     

模拟高原低氧对大鼠脑内神经胶质细胞的影响

目的：观察模拟高原低氧对成年大鼠脑内胶质细胞的影响。方法：大鼠在模拟海拔4000m高原低压舱内连续暴露1、3、7d,胶质原纤维酸性蛋白（GFAP）与Griffoniasimplicifolia同功凝集素（GSA-IB4）组织细胞化学分别显示星形胶质细胞与小胶质细胞。结果：GFAP与GSA-IB4阳性细胞在低氧后3．7d两个时相显著增多,主要分布于新皮层、海马、纹状体及室管膜下层等区域。结论：模拟高原低氧能引起大鼠脑内星形胶质细胞与小胶质细胞的显著活化。     

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.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

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.