Selective angiotensin II AT2 receptor agonists: Benzamide structure-activity relationships

In the investigation of the structure-activity relationship of nonpeptide AT(2) receptor agonists, a series of substituted benzamide analogues of the selective nonpeptide AT(2) receptor agonist M024 have been synthesised. In a second series, the biphenyl scaffold was compared to the thienylphenyl scaffold and the impact of the isobutyl substituent and its position on AT(1)/AT(2) receptor selectivity was also investigated. Both series included several compounds with high affinity and selectivity for the AT(2) receptor. Three of the compounds were also proven to function as agonists at the AT(2) receptor, as deduced from a neurite outgrowth assay, conducted in NG108-15 cells.     

广西不同时期IBV分离株S1基因高变区Ⅰ的遗传变异分析

对广西1985～2007年间分离到的22株传染性支气管炎病毒(IBV)的S1基因高变区Ⅰ(HVR Ⅰ)进行序列测定,并与发表的其他IBV参考株及鸽子分离的冠状病毒株的基因序列进行比较和分析.系统进化关系显示毒株可分为5个基因群,其中有16个广西分离株属第Ⅰ群,它们与鸽子冠状病毒分离株的氨基酸序列同源性较高,与Massachusetts(Mass)型疫苗株的同源性较低.有15个分离株在33～34位和34～35之间分别有4个和3个氨基酸残基的插入,GX-NN6在33～34位和34～35位之间则均有4个氨基酸残基的插入;GX-YL1、GX-NN2与常用的Mass型疫苗株的亲缘关系最近,同属于第Ⅱ群;GX-G、GX-XD与日本同一时期分离的毒株JP Miyazaki 89亲缘关系最近,属于第Ⅲ群;GX-YL6、GX-NN7与欧洲毒株4/91亲缘关系较近,属于第V群.结果表明广西存在着多种类型IBV毒株的流行,毒株S1基因HVR Ⅰ碱基的突变或插入比较普遍,可导致其氨基酸序列的变化,绝大部分毒株与目前常用的Mass型疫苗株的亲缘关系较低.同一时期的分离株同源性较高,但无明显的地域性差异.     

鼎湖山马尾松、荷木混交林生态系统碳素积累和分配特征

选取鼎湖山保护区3个马尾松9Pinus massoniana),荷木（Schima superba)针阔混交林样地,研究其生态系统的碳素积累和分配特征。结果表明,鼎湖山马尾松,荷木混交林乔木尾生物量（thm^-2)为：174.41-270.11。平均227.36,且均以马尾松的生物量居多（占54.9%-84.4%)。林下层植物生物量和地表现存凋落物量（thm^-2)分别为7.41-28.28和7.06-11.56。平均14.41和9.03。三个混交林生态系统总碳贮量（thm^-2)分别为146.35,215.30和205.79。平均为189.15,其中植被层碳贮量贡献率最大,依次占62.9%,61.9%和69.9%。平均65.0%;土壤层贡献率次之,依次占34.3%,35.5%和28.5%。平均32.8%;而地表现存凋落物层的贡献最小,仅占2.8%,2.6%和1.6%。平均为2.3%。此外,本文还对该生态系统植被碳吸存潜力进行了讨论。     

携带EBV-LMP2基因的DNA疫苗、腺相关病毒疫苗和腺病毒疫苗免疫小鼠的特异性细胞免疫应答

细胞免疫应答, 尤其是CD3⁺CD8⁺细胞毒性T淋巴细胞(cytotoxic T lymphocyte, CTL), 在控制病毒感染中扮演着重要角色. 鼻咽癌(nasopharyngenl carcinoma, NPC)与EB病毒(epstein-barr virus, EBV)持续感染密切相关, 在鼻咽癌疫苗的研究中, 人们将研究重点放在增强特异性抗病毒CTL应答上. 本研究单独或联合使用表达EB病毒潜伏膜蛋白抗原2(epstein-barr virus latent membrane protein 2, EBV-LMP2)的DNA疫苗、腺相关病毒(adeno-associated virus, AAV)疫苗、非复制5型腺病毒疫苗(Ad5), 分别于0, 2, 4周肌肉注射免疫4~6周龄的雌性Balb/C小鼠, IFN-γ 免疫斑点法检测EBV-LMP2特异性细胞免疫应答水平. 疫苗诱导的特异性细胞应答水平与疫苗的免疫策略有关. 其中, 使用3种载体疫苗联合免疫的效果最好, 其次则是先使用DNA疫苗免疫两次, 再用腺病毒疫苗加强免疫一次的联合免疫方法. DNA疫苗和AAV疫苗单独免疫能够诱导出特异性的CTL, 但与联合免疫相比诱导的应答水平很低. 结果表明, 使用DNA, AAV和腺病毒载体疫苗联合免疫, 能够更好地诱导机体产生特异性细胞免疫应答, 为鼻咽癌的防治提供了很好的疫苗策略.     

Rapid Purification and High Sensitivity Analysis of Heparan Sulfate from Cells and Tissues: TOWARD GLYCOMICS PROFILING*?

Studies on glycosaminoglycans and proteoglycans (PGs) have been hampered by difficulties in isolation and analysis by traditional methods that are laborious and lack sensitivity and throughput. Here we demonstrate a simple method for rapid isolation of proteoglycans (RIP) employing phenol/guanidine/chloroform reagent to purify heparan sulfate (HS) PGs quantitatively from various tissues and cells. We further show that this generic purification methodology, when applied in concert with a BODIPY^TM fluorescent label, permits structural analyses on RIP-purified HS at ∼1,000-fold higher sensitivity than standard UV detection methods and ∼10–100-fold higher sensitivity than previous fluorescence detection methods. The utility of RIP-BODIPY methodology was demonstrated by rapid profiling of HS structural composition from small tissue samples, multiple mouse organs, and as little as a few thousand cultured cells. It was also used to generate novel insights into in vivo structural changes in HS from Sulf1 knock-out mice for the first time that differed significantly from previous observations limited to tissue culture experiments. RIP was also applied to purify HS for bioassay testing, exemplified by cell assays of fibroblast growth factor signaling activation; this generated data from 2-O-sulfotransferase knock-out mice and revealed an unexpected deficiency in fibroblast growth factor activation by HS from heterozygous mice. These data demonstrate that RIP will underpin emerging efforts to develop glycomics profiling strategies for HS and other glycosaminoglycans to explore their structure-function relationships in complex biological systems.Heparan sulfate (HS)³ is a member of the glycosaminoglycan (GAG) family of polysaccharides and is found on almost all cell types in metazoan organisms, attached to core proteins to form specialized glycoproteins called proteoglcans (PGs). It is critical in many biological processes (including embryonic development, homeostasis, and wound healing), and lack of HS is lethal in higher organisms such as mice (1, 2). HS is also involved in a variety of disease processes (such as tumor angiogenesis, pathogen adhesion, and neurodegeneration). It carries out these functions primarily by binding to many different proteins and regulating their functions (1, 3). Specific binding is in part determined by the variation in structure of the HS, primarily in the number and location of sulfate moieties (4, 5). There is now intense interest in identifying specific structural motifs within HS responsible for binding and regulation of particular proteins and in exploring the heparanome, the entire complements of HS structures expressed by cells and tissues (1, 3, 6).The study of HS biochemistry and its interactions with proteins (3, 4) necessitates the ability to purify and analyze HS from tissues and cells. However, current methods of purification (such as detergent and guanidium salt extraction followed by protease digestion or chloroform/methanol extraction), although good at purifying HS in large amounts from single sources, suffer several drawbacks. They are lengthy and laborious (involving complex extraction processes and multiple column chromatographic steps) and can also result in alteration of native structure, for example N-desulfation (7–10). To address these problems, our rationale was to devise a simple extraction and purification protocol that was both rapid and streamlined, minimizing transfers to reduce losses in yield and providing HS of sufficient purity for comparative structural and functional analysis. We observed that PGs partition exclusively in the aqueous phase in extractions performed with TRIzol® (a well known phenol/guanidine/chloroform reagent that is widely used to purify DNA and RNA from tissues) (11). This observation led us to develop a method for isolation of PGs, exemplified by HSPGs. Here we demonstrate a novel approach for the rapid isolation of proteoglycans (RIP) from most tissues and cell culture samples that is quick (from cell/tissue sample to ion exchange purification in ∼30 min), reduces loss of material (only one transfer before ion exchange step), and is readily scalable. Furthermore, when coupled to a recently developed method for highly sensitive fluorescent labeling of GAG saccharides with BODIPY^TM hydrazide (12), RIP allows the structural profiling and bioassay of HS from less than a milligram of starting tissue or a few thousand cells.     

药用植物艾纳香基因组DNA提取方法研究

以药用植物艾纳香为研究对象,以-20℃保存、4℃保存、室温自然干燥和硅胶干燥四种样品保存方式,并采用SDS法、CTAB法、SDS-CTAB法和改良CTAB法4种不同的基因组DNA提取方法进行了对比试验,以期建立艾纳香的较好的样品保存方法和基因组DNA提取方法。结果表明,-20℃保存是艾纳香的较理想的样品保存方式;改良CTAB法是艾纳香基因组DNA提取较适宜的方法,该方法提取的DNA经紫外检测,其A_(260)/A_(280)为1.8左右,明显优于SDS法(1.1～1.5)、CTAB法(1.2～1.5)和SDS-CTAB法(1.4～1.6),琼脂糖凝胶电泳、酶切检测和PCR扩增也得出了同样的结论。     

食物丰容对圈养猩猩行为的影响

于2007年2～4月对成都动物园圈养猩猩"铁里"进行了两个食物丰容试验,即用PVC+轮胎和圆木+轮胎试验,每期8 d,观察和记录了猩猩在丰容试验前、后以及两种丰容方式中的各种行为发生次数.结果 表明食物丰容有效地恢复了圈养猩猩的多种摄食行为,增加了猩猩的运动相关行为,减少了休息相关行为;但对刻板行为的影响不明显.     

荧光定量PCR技术评价亚甲蓝光化学法病毒灭活效果的研究

本研究探讨利用荧光定量PCR技术评价Sindbis病毒经亚甲蓝光化学处理后灭活效果的可行性。研究采用不同光照强度对Sindbis病毒进行亚甲蓝光化学灭活处理,并用SYBR Green I荧光定量PCR对Sindbis病毒的cDNA进行扩增,同时以细胞病变法做平行对照以测定病毒残余滴度。结果显示在亚甲蓝光化学处理过程中,随着光照强度的增强,病毒残余滴度由6.50 LgTCID50/mL逐渐降低至检测限以下,同时病毒核酸的拷贝数显著下降(P<0.05),并与病毒感染性的降低呈线性相关(R2>0.98)。以上结果表明,亚甲蓝光化学灭活法对Sindbis病毒核酸有破坏作用,病毒核酸损伤程度随光照强度的增强而增加,且与病毒感染性的降低存在相关性,提示荧光定量PCR技术评价亚甲蓝光化学法的病毒灭活效果具有可行性。     

浙江短角瘿蚊属一新种记述(双翅目:瘿蚊科)

记述采自浙江省的短角瘿蚊1新种:狭短角瘿蚊Anarete angusta Mo et Xu,sp.nov..     

短小芽孢杆菌2080碱性蛋白酶的纯化与性质

短小芽孢杆菌（Bacillus pumilus）2080碱性蛋白酶的发酵液经超滤、硫酸铵沉淀、CM Sepharose Fast Flow和DEAE Sepharose Fast Flow离子交换层析得到了纯化的组分。SDS-PAGE电泳分析显示其分子量约为61kDa。酶学性质研究表明,该纯化酶的最适pH为10．5,最适温度为50℃。