胎脑提取液对衰老小鼠海马神经元酶活性影响的实验研究

目的 观察胎脑提取液对衰老小鼠海马神经元酸性磷酸酶（ACP）和琥珀酸脱氢酶（SDH）活性的影响,探讨胎脑提取液的抗衰老作用。方法 选用健康昆明种小白鼠30只,随机分为3组;采用D-半乳糖制备亚急性衰老模型;酶组织化学方法结合显微图像分析。观察各组小鼠海马神经元ACP和SDH的活性。结果 衰老模型组与正常对照组相比,小鼠海马神经元ACP活性明显升高,SDH活性明显降低;给药组与衰老模型组相比,小鼠海马神经元ACP活性明显降低。SDH活性明显升高。结论 胎脑提取液可以延缓海马神经元的衰老进程,具有一定的抗衰老作用。     

胎脑提取液对衰老小鼠大脑皮质神经元的影响

目的 观察胎脑提取液对衰老小鼠大脑皮质神经元酸性磷酸酶(ACP)活性和尼氏体含量的影响,探讨胎脑提取液的抗衰老作用。方法 选用健康昆明种小白鼠30只,随机分为3组;采用D-半乳糖制备亚急性衰老模型;组织化学方法显示大脑皮质神经元内的酸性磷酸酶(ACP)和尼氏体;显微图像分析仪进行定量分析。结果 衰老模型组与正常对照组相比,小鼠大脑皮质神经元ACP活性明显升高,尼氏体含量明显减少;给药组与衰老模型组相比,小鼠大脑皮质神经元ACP活性明显降低,尼氏体含量明显增加。结论 胎脑提取液可以稳定大脑皮质神经元的内环境,减少神经元的损伤,促进神经元蛋白质的合成,具有一定的抗衰老作用。     

土人参提取液对D-半乳糖所致衰老小鼠的抗氧化作用研究

本文研究了土人参提取液对D-半乳糖所致衰老小鼠的抗氧化作用的影响。取昆明种小白鼠50只,随机分为5组(正常对照组、衰老模型组、土人参提取液低、中、高剂量组)。除正常对照组外,其余各组每天于颈背皮下注射D-半乳糖125 mg/kg,连续42 d,造成亚急性衰老模型。在注射D-半乳糖的同时,三个不同剂量实验组每天分别灌胃土人参提取液5、10和15g/kg,正常对照组及衰老模型组给予等量生理盐水。于42 d后测定小鼠体内超氧化物歧化酶(Super Oxide Dismutase,SOD)、谷胱甘肽过氧化物酶(Glutathione peroxidase,GSH-PX)等酶的活性,及丙二醛(Maleic Dialdehyde,MDA)的含量。结果显示:与正常对照组相比,衰老模型组小鼠心脏、肝脏组织SOD及血清中GSH-PX活性降低(P0.01),MDA含量增加(P0.01)。与衰老模型组相比,土人参提取液低、中、高剂量组小鼠心脏、肝脏组织SOD及血清中GSH-PX活性明显升高(P0.01);中、高剂量组小鼠心脏、肝脏组织中MDA含量降低明显(P0.01),低剂量组小鼠肝脏的MDA含量明显降低(P0.01)。上述结果表明:土人参提取液对D-半乳糖所致衰老小鼠有抗衰老作用。     

阿里红黄酮对衰老模型小鼠的抗衰老作用

目的：研究阿里红黄酮对衰老模型小鼠的抗衰老作用。方法：将小鼠随机分为6组（n=12）：正常对照组,衰老模型组,阳性对照组,低、中、高剂量阿里红黄酮组。除正常对照组外,其余各组均采用D-半乳糖颈背部皮下注射建立亚急性衰老小鼠模型,用不同剂量的阿里红黄酮（100、200和400 mg/（kg·d））灌服小鼠6周后,计算衰老模型小鼠脑指数及脾脏指数、胸腺指数,测定其脑组织丙二醛（MDA）含量及谷胱甘肽过氧化物酶（GSH-Px）活性、肝组织过氧化氢酶（CAT）及超氧化物歧化酶（SOD）活性。结果：阿里红黄酮3个剂量组可不同程度的升高衰老模型小鼠的脑指数、脾脏指数、胸腺指数、脑组织中的GSH-Px活性及肝组织中的CAT、SOD活性,降低其脑组织中的MDA含量。结论：阿里红黄酮可能通过提高机体的抗氧化能力而达到抗衰老作用。     

重症急性胰腺炎大鼠血浆NO、ET、TNF-α含量与亚细胞器某些指标的变化

目的：探讨一氧化氮(NO)、内毒素(ET)、TNF-α在重症急性胰腺炎(SAP)中的作用机制。方法：采用1.5％去氧胆酸钠逆行胆胰管内注射建立SAP模型,观察血中NO、ET、TNF-α水平以及线粒体琥珀酸脱氢酶(SDH)活性、溶酶体酸性磷酸酶(ACP)释放率、微粒体细胞色素P450的变化,并进行相关分析。结果：与对照组比较,模型组NO、ET、TNF-α和ACP释放率明显升高,SDH活性和细胞色素P450则显著降低;相关分析显示NO、ET、TNF-α与ACP释放率、SDH、细胞色素P450具有相关性。结论：NO、ET、TNF-α可直接破坏胰腺细胞亚细胞器结构,引起胰腺损伤。     

大豆异黄酮对游泳小鼠能量代谢的影响

目的：探讨大豆异黄酮（SI）对游泳小鼠能量代谢的影响。方法：建立小鼠运动疲劳模型,选用雄性昆明小鼠30只,根据体质量随机分为3组（n=10）：正常组、游泳模型组、游泳+SI干预组（SI组）。正常组及模型组小鼠以AIN-93M合成饲料饲养,SI组在AIN-93M合成饲料中添加相应剂量的SI （4 g/kg）。饲养2周后,模型组和SI组小鼠负重2%游泳1 h后处死,测定其血乳酸（Lac）含量及乳酸脱氢酶（LDH）、琥珀酸脱氢酶（SDH）、肌酸激酶（CK）、ATP酶的活性。结果：与正常组相比,模型组和SI组血清中Lac含量明显增加（P<0.05）,模型组肌肉和SI组血中LDH活性显著升高（P<0.05）,模型组血清、肝脏和肌肉中SDH和CK活性明显升高,SI组血清和肌肉中SDH和CK活性显著升高（P<0.05）;与模型组相比,SI组小鼠游泳后,血清Lac含量明显下降（P<0.05）,LDH、SDH、CK酶活性较模型组都有明显升高（P<0.05）。结论：大豆异黄酮对游泳小鼠能量代谢具有一定的调节作用。     

延衰合剂对D-半乳糖衰老模型小鼠学习记忆及抗氧化能力的影响(英文)

为观察延衰合剂(Yanshuai mixture,YSM)的延缓衰老作用,采用D-半乳糖连续颈背部皮下注射诱导亚急性衰老小鼠模型,造模同时给予YSM低、中、高剂量灌胃,连续10周。观察小鼠衰老征象,Moriss水迷宫检测学习记忆功能,测定血清及脑组织中总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)、丙二醛(MDA)。结果显示,与模型组比较,YSM各剂量组均能使小鼠逃避潜伏期明显缩短,原平台象限游泳时间明显延长(P<0.05);YSM高剂量组T-AOC、SOD活性显著升高(P<0.01),MDA水平显著下降(P<0.01)。表明YSM可明显改善衰老小鼠学习记忆功能,提高抗氧化能力,从而可能具有较好的延缓衰老的作用。     

白藜芦醇抗衰老作用的实验研究

目的：探讨白藜芦醇的抗衰老作用。方法：采用避暗实验观察白藜芦醇对小鼠学习记忆的影响,通过常压耐缺氧、断头耐缺氧、亚硝酸钠中毒造成的缺氧以及负重游泳实验,观察白藜芦醇对小鼠缺氧及耐力的影响;以AlCl3造成急性衰老小鼠模型,观察白藜芦醇对小鼠血中超氧化物歧化酶（SOD）活性的影响。结果：白藜芦醇各剂量组均能明显改善记忆障碍,与模型组比较差异有显著性（P〈0.01）。在耐力实验中,白藜芦醇可显著延长小鼠缺氧时间,与溶剂组比较有显著性差异（P〈0.05）。结论：白藜芦醇具有一定的抗衰老作用。     

蜂胶黄酮对小鼠脑so D 、 GsH 一Px 、 MDA 的影响

目的：研究蜂胶黄酮对小鼠脑组织的抗氧化系统的作用,以期探讨蜂胶黄酮的抗衰老作用机制。方法：以小鼠为实验对象,以其脑SOD、GSH—Px、MDA为指标,考察蜂胶黄酮的抗衰老作用。结果：蜂胶乙醇提取物（EEP）可使脑组织中SOD、GSH—Px活性明显增高,和空白组相比具有显著差异（P〈0、01）;使脑组织MDA明显降低,和空白组相比具有显著差异（P〈0．01）。结论：EEP可有效地提高脑组织中抗氧化酶的活性,降低脑MBA的含量,抑制和／或减轻脂质过氧化反应,从而防止了自由基过氧化对脑组织的损伤,可能是有效的脑组织保护荆。     

脐血间充质干细胞对小鼠辐射性肝损伤的作用

目的:研究脐血间充质干细胞(UCMSC)对全身X线受照小鼠的肝组织辐射损伤后的防护作用,为相关放射性肝疾病的治疗提供理论依据。方法:选取清洁级SD小鼠进行全身辐射,建立小鼠辐射损伤模型,观察辐射前后小鼠的一般状态;给小鼠注射UCMSC悬浮液1 m L和等体积生理盐水,分别于处理后第1、2、7、14 d取小鼠肝脏,用苏木精-伊红染色,观察辐射后肝组织病理形态学的变化;取肝脏组织匀浆检测丙二醛(MDA)含量和超氧化物歧化酶(SOD)的活性。结果:辐射组小鼠与正常组小鼠相比活动明显减少,治疗后的小鼠状况有所恢复;肝组织石蜡切片染色显示,按组织学标准评价后各组肝组织比较有显著性差异;辐射组与正常组比较,肝细胞内MDA含量显著升高,SOD活性显著降低,差异有统计学意义;普通组与辐射组比较,肝细胞内MDA含量有所降低,SOD活性有所升高有明显改善作用;加强组与普通组比较,MDA含量降低,SOD活性有所升高。结论:脐血间充质干细胞移植具有清除自由基、减轻肝损伤及修复再生损伤肝细胞的作用,能够有效改善肝脏损伤。     

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.     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

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