白藜芦醇甙对糖尿病小鼠心肌损伤的保护作用及机制研究

目的:探讨白藜芦醇甙对小鼠小鼠心肌损伤的影响及其可能的调控机制。方法:采用腹腔注射链脲霉素的方法建立1型糖尿病小鼠模型模型,随机将雄性C57/BL6J的正常小鼠和糖尿病小鼠分为3组(每组18只):对照组、糖尿病组、糖尿病+白藜芦醇甙组。其中糖尿病+白藜芦醇甙组给予白藜芦醇甙7.5 mg/kg/d腹腔注射治疗,对照组和糖尿病组给予同体积盐水腹腔注射。药物治疗12周后,小动物心脏超声检测小鼠的心功能;天狼星红染色观察胶原变化并进一步计算胶原容积分数(collagen volume fraction,CVF);柠檬酸合酶检测试剂盒和ATP生物荧光试剂盒分别检测检测心肌柠檬酸合酶活性和ATP含量;Western blot检测Sirt3和p-AMPK的蛋白表达情况。结果:与对照组相比,糖尿病组LVEDD和LVESD均明显增加(4.823±0.103 mm和3.701±0.121 mm,P0.05),LVEF和LVFS值均明显降低(37.121±4.298%和21.023±2.187%,P0.05),CVF显著增高(20.102±1.155%,P0.05),心肌柠檬酸合酶活性和ATP含量显著降低(5.267±0.202 nmol/g和105±7.638 U/g,P0.05),Sirt3和p-AMPK蛋白表达显著降低(P0.05);与糖尿病组相比,糖尿病+白藜芦醇甙组LVEDD和LVESD均显著降低(4.354±0.113 mm和3.056±0.130 mm,P0.05),LVFS和LVEF值均显著增加(58.435±8.143%和29.071±2.232%,P0.05),CVF显著降低(10.343±0.882%,P0.05),心肌柠檬酸合酶活性和ATP含量显著增加(6.233±0.176 nmol/g和132.7±5.774 U/g,P0.05),Sirt3和p-AMPK蛋白表达显著增加(P0.05)。结论:白藜芦醇甙可改善糖尿病小鼠心肌损伤,其机制可能与白藜芦醇甙激活Sirt3/AMPK信号通路有关。     

MiR-182模拟物提高1型糖尿病小鼠的心脏功能

目的探讨miR-182模拟物对1型糖尿病小鼠心脏功能的影响及可能作用机制。方法 40只8周龄雄性C57小鼠随机分为正常对照组(n=5),miR-182模拟物对照组(n=5),1型糖尿病组(n=15),1型糖尿病+miR-182模拟物治疗组(n=15)。腹腔注射链脲佐菌素(STZ)建立1型糖尿病动物模型。实验于8周末结束,采用小动物用高分辨超声仪测量小鼠心脏功能;运用透射电镜观察心肌组织超微结构改变;利用real-time PCR技术检测心肌组织β-肌球蛋白重链(β-MHC),α-肌球蛋白重链(α-MHC),心房钠尿肽(ANP),I型(Col I)和III型胶原(Col III)mRNA及miR-182 mRNA的表达含量。结果 1miR-182模拟物可改善1型糖尿病小鼠的心脏功能,增加心脏射血分数及左室短轴缩短率(P0.01);2miR-182模拟物可降低糖尿病小鼠心肌组织ANP、Col I、Col III的表达及β/a-MHC比值(P0.01);3miR182模拟物可改善1型糖尿病小鼠心肌超微结构变化,减轻自噬。结论MiR-182模拟物能改善1型糖尿病小鼠的心脏功能,其机制可能与减轻心肌肥大和心肌纤维化,减轻线粒体结构损伤及减轻自噬有关。     

黄酒多酚对糖尿病心肌病大鼠心肌细胞凋亡的影响

目的:探究黄酒多酚对糖尿病心肌病大鼠心肌细胞凋亡的影响。方法:将30只雄性SD大鼠随机分为空白对照组(Control组)、糖尿病心肌病组(DCM组)、糖尿病心肌病+黄酒多酚组(DCM+YWP组)(n=10)。采用单次腹腔注射65 mg/kg链脲佐菌素(STZ)构建糖尿病心肌病大鼠模型,对照组采用相同剂量的枸橼酸缓冲液进行单次腹腔注射,DCM+YWP组建模后用18 mg/kg黄酒多酚灌胃。12周后观察大鼠一般情况,用多普勒心超评价心脏结构和功能,用电镜观察心肌组织超微结构,用ELISA法检测心肌组织炎症指标,用氧化应激指标检测试剂盒检测心肌组织氧化应激水平,用Westen blot检测心肌组织凋亡相关蛋白Bax、Bcl-2和Caspase-3(cleaved)的表达水平。结果:与DCM组相比,DCM+YWP组大鼠血糖水平及体重未出现明显变化;心脏超声显示左室舒张末期直径,左室收缩末期直径降低(P0.05),而左室缩短率、左心室射血分数、E/A比值以及Ea/Aa比值均升高(P0.05);心肌组织肿瘤坏死因子α(TNF-α)、白介素1β(IL-1β)以及白介素6(IL-6)水平下降(P0.05);心肌组织氧化应激指标丙二醛(MDA)水平下降、超氧化物歧化酶(SOD)以及谷胱甘肽过氧化物酶(GSH-Px)水平上升(P0.05);心肌组织Bax、Caspase-3(cleaved)蛋白的表达水平降低(P0.05),Bcl-2蛋白的表达水平升高(P0.05)。结论:黄酒多酚能改善糖尿病心肌病大鼠的心脏功能,降低心肌组织炎症因子和氧化应激水平,抑制糖尿病心肌病大鼠心肌细胞凋亡。     

链脲佐菌素诱导糖尿病肺纤维化小鼠模型的建立与评价

目的 探究链脲佐菌素(streptozotocin, STZ)诱导糖尿病肺纤维化(diabetic pulmonary fibrosis, DPF)小鼠模型的建立方法,为临床研究提供稳定的DPF动物模型。方法 将60只雄性C57BL/6小鼠随机分为3组：正常对照组(NG,n=20)、糖尿病肺纤维化1组(DPF1,n=20)、糖尿病肺纤维化2组(DPF2,n=20)。隔夜禁食不禁水后测定小鼠空腹血糖和体重,随后DPF1组一次性腹腔注射大剂量STZ(150 mg/kg),DPF2组连续5 d每天腹腔注射小剂量STZ(50 mg/kg),NG组腹腔注射等量无菌柠檬酸盐缓冲液。注射完毕后,每天观察小鼠的一般情况,每周测定小鼠体重和随机血糖(random blood glucose, RBG),正常喂养16周,每4周每组随机选取5只小鼠处死取材,行病理和分子生物学检测,评估小鼠肺纤维化的程度。结果 STZ诱导后,DPF1组和DPF2组均出现“多饮、多尿、多食、体重减轻(三多一少)”的典型糖尿病症状。DPF1组和DPF2组诱导后体重增加均显著低于NG组,并于第8周后缓慢减轻(P<0.05);...     

GDF11对Ⅱ型糖尿病小鼠心肌损伤的保护作用

目的观察GDF11对Ⅱ型糖尿病C57BL/6J小鼠心肌损伤的保护作用及心肌凋亡水平的变化情况。方法 60只体重20~25 g的雄性C57BL/6J小鼠,随机分为3个组:正常对照组(control)、II型糖尿病模型组(DM)和GDF11干预组(DM+GDF11)。高脂高糖饲料饲养4周后,连续3次腹腔注射60 mg/kg链脲佐菌素(STZ),建立II型糖尿病小鼠模型,持续高脂高糖饲料饲养4周后,小动物超声检测心功能,取心肌组织,TUNEL染色检测心肌组织凋亡比例,Western blot法检测凋亡相关蛋白cleaved-caspase-3、Bcl-2和Bax的表达。结果糖尿病损伤显著下调左室射血分数和左室短轴缩短率,增加心肌凋亡率,而给予重组GDF11蛋白能够明显改善心功能并减轻心肌凋亡。结论外源性的GDF11可以显著减轻糖尿病损伤后心肌凋亡水平,改善心功能。     

烟酰胺核糖抑制db/db小鼠糖尿病心肌病的作用及机制研究

目的:探讨烟酰胺核糖(NR)对2型糖尿病小鼠心肌病的治疗作用及其机制。方法:2型糖尿病模型db/db鼠和及其严格对照小鼠db/+小鼠,将小鼠分为Con (db/+)组,DM (db/db)组,DM+NR组。采用超声测小鼠心脏功能,western-blot及免疫组化测SIRT1表达含量,DHE染色、MDA含量和MnSOD活性检测反映氧化应激水平。结果:与对照组相比,db/db小鼠心脏功能显著下降(LVEF:42.3±7.2vs 73.7±10.2, P0.01;LVFS:22.1±4.2vs 42.7±6.9, P0.01),SIRT1表达量显著下调(P0.01)。NR喂养提高SIRT1表达量(P0.01),并有效改善db/db小鼠心脏功能(LVEF:53.1±8.1vs 42.3±7.2, P0.01;LVFS:33.4±6.9vs 22.1±4.2, P0.01)。同时,NR喂养显著降低了db/db小鼠心肌组织的凋亡水平和氧化应激水平(P0.05)。结论:NR有效改善了db/db小鼠的心功能障碍,降低了db/db小鼠的心肌凋亡水平和氧化应激水平,这些作用的发挥可能与NR增加SIRT1的表达量有关。     

FrzA基因转导干预缺血性心力衰竭小鼠心肌Wnt信号通路的研究

目的:研究重组9型腺相关病毒(recombinant adeno-associated virus serotype 9,rAAV9)携带FrzA基因转导干预缺血性心衰小鼠心肌Wnt信号通路的可行性,为基因治疗心力衰竭提供新的思路.方法:选择3月龄雄性C57BL/6J小鼠共130只,随机分为空白组(n=10),心衰组(n=40),心衰+空病毒(rAAV9-GFP)注射组(n=40),心衰+rAAV9-FrzA组(n=40),采用结扎左冠状动脉定量控制心梗面积,于术后2周行心脏超声评各组心功能变化,再经尾静脉注射已稀释好的病毒,28d后处死小鼠取心脏标本,RT-PCR检测心肌目的基因FrzA以及Dvl-1,β-catenin的表达;Western blot检测心肌Wnt信号通路关键分子Dvl-1,GSK3β,p-GSK3β,β-catenin的表达.结果:与空白组相比,成功建立心衰模型后小鼠心功能均不同程度降低(P＜0.05);FrzA组与心衰组相比,心功能明显改善(P＜0.05);经尾静脉注射可成功将rAAV9-FrzA导入小鼠体内,并且目的基因FrzA在心肌组织中高表达(P＜0.05);心衰小鼠心肌中Wnt信号通路关键分子Dvl-1,p-GSK3β,β-catenin的表达显著升高(P＜0.05),FrzA转导后小鼠心肌中Wnt信号通路中关键分子Dvl-1,p-GSK3β,β-catenin表达均降低(P＜0.05)结论:利用rAAV9-FrzA转导缺血性心衰小鼠可以有效的干预心肌Wnt信号通路,抑制其活性,为基因治疗缺血性心衰提供了新的思路.     

人参皂苷Rb1通过上调PGC-1α缓解糖尿病心肌病

目的:研究人参皂苷Rb1对糖尿病心肌病的治疗作用并阐明其分子机制。方法:采用腹腔注射链脲佐菌素的方法,建立糖尿病心肌病动物模型。将小鼠分为3组:WT组,DM组,DM+Rb1组。超声心动图分析小鼠心功能;Western blot分析PGC-1α、cleaved caspase-3、bcl-2等蛋白表达;MitoSOX染色分析线粒体ROS含量;透射电镜分析线粒体数目。结果:与WT组相比,DM组小鼠心功能显著下降(LVEF,P<0.01),PGC-1α表达下调(P<0.01),线粒体数目减少(P<0.01);而Rb1处理后,显著改善了DM小鼠心功能(LVEF,P<0.01),恢复了PGC-1α表达(P<0.05),增加了线粒体数目(P<0.05)。同时,Rb1处理后,减少了糖尿病小鼠心肌线粒体ROS产生(P<0.01),恢复了bcl-2蛋白表达(P<0.01),降低了cleaved caspase-3蛋白表达(P<0.01),从而减少了高糖引起的细胞凋亡(P<0.05)。而siPGC-1α处理后,阻断了Rb1的上述作用。结论:人参皂苷Rb1通过上调PGC-1α改善糖尿病小鼠心功能,缓解糖尿病心肌病。其机制可能与人参皂苷Rb1降低心肌线粒体ROS产生并减少心肌细胞凋亡有关。     

激光多普勒对糖尿病小鼠微循环自律运动功能的评估

目的:探讨激光多普勒对糖尿病小鼠微循环自律运动功能的评估价值。方法:20只BALB/c小鼠随机分为糖尿病组(n=10)和对照组(n=10)。连续5天腹腔注射40 mg/kg STZ诱导糖尿病模型;应用Moor LDLS检测糖尿病小鼠皮肤微循环血流灌注水平;应用Moor VMS-LDF检测糖尿病小鼠胰腺微循环血流灌注及微血管自律运动功能。结果:糖尿病小鼠皮肤微循环血流灌注显著降低,皮肤总血流灌注量(P=0.009)、胰腺微血管自律运动频率(P0.001)和振幅(P0.001)均显著低于对照组小鼠。结论:联合应用Moor LDLS激光多普勒扫描成像系统及Moor VMS-LDF激光多普勒血流灌注监测系统可作为糖尿病小鼠微循环功能状态的评估手段。     

碱性成纤维生长因子转染骨髓间充质干细胞移植对心肌病心力衰竭大鼠心功能的影响

目的探讨碱性成纤维生长因子(bFGF)转染的骨髓间充质干细胞(BMSCs)移植对心肌病心力衰竭大鼠心功能的影响。方法通过腹腔注射阿霉素建立心肌病心力衰竭SD大鼠模型,存活33只大鼠随机分成3组:模型组、BMSCs组和BMSCs+bFGF组,每组11只。另设正常对照组(n=8)。取体外培养的第三代SD大鼠BMSCs,质粒-bFGF转染BMSCs,BrdU标记后,分别将BMSCs(3×10~6个)、bFGF转染的BMSCs(3×10~6个)或等体积培养基通过尾静脉注射的方法进行移植。用生物信号采集系统检测大鼠心功能,大鼠心脏切片行免疫组化了解移植细胞在受体心脏的存活情况,实时荧光定量PCR和Western Blotting检测心室组织bFGF的表达水平。多组间比较采用单因素方差分析或精确概率法。结果 BMSCs移植4周后,正常对照组大鼠的心功能指标LVSP(121.13±12.28)mmHg,LVDEP(3.86±1.25)mmHg,LV+d P/dt(3671.25±172.50)mmHg/s和LV-d P/dt(3221.63±259.57)mmHg/s;模型组心功能指标LVSP(81.29±12.39)mmHg,LVDEP(16.43±4.12)mmHg,LV+d P/dt(2344.29±98.63)mmHg/s和LV-d P/dt(2244.29±103.10)mmHg/s;BMSCs组心功能指标LVSP(97.00±6.39)mmHg,LVDEP(12.00±2.73)mmHg,LV+d P/dt(2876.25±118.31)mmHg/s和LV-d P/dt(2726.25±303.23)mmHg/s;BMSCs+bFGF组心功能指标LVSP(109.38±12.78)mmHg,LVDEP(9.25±1.67)mmHg,LV+d P/dt(3037.50±161.22)mmHg/s和LV-d P/dt(3000.13±149.77)mmHg/s,移植组各指标均有改善,比较差异有统计学意义(F=17.29、36.61、111.11、26.54,P均0.01)。免疫组织化学检查示细胞移植组大鼠的心室组织切片上可见Brd U阳性细胞存在。模型组大鼠心室心肌组织bFGF mRNA表达水平高于正常对照组(1.28±0.06 vs 1.00±0.00,t=10.46,P0.01),BMSCs组高于模型组(1.37±0.05 vs 1.28±0.06,t=3.39,P0.01),而BMSCs+bFGF组高于BMSCs组(1.44±0.03 vs 1.37±0.05,t=2.86,P=0.01)。Western Blotting示,正常对照组大鼠心室组织bFGF蛋白表达最低,模型组高于正常对照组(1.31±0.09 vs 1.00±0.00,t=5.48,P=0.01),BMSCs组高于模型组(1.46±0.05 vs 1.31±0.09,t=2.68,P=0.03),而BMSCs+bFGF组高于BMSCs组(1.84±0.09 vs 1.46±0.05,t=6.79,P0.01)。结论转染bFGF基因的BMSCs移植可提高阿霉素所致心肌病心力衰竭大鼠心脏的bFGF水平,改善大鼠心功能,其效果优于单纯BMSCs移植。     

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.