沙棘籽渣水提物对正常和糖尿病小鼠血糖的影响

本文研究了沙棘籽渣水提物(Aqueous extract of seabuckthorn seed residues,ASSR)对正常及糖尿病小鼠血糖、血脂代谢的影响。首先采用ASSR灌胃昆明种小鼠的急性毒性试验评价了ASSR的安全性;继而以250mg/kg和500 mg/kg剂量的ASSR连续灌胃正常小鼠3周;以250、500和800 mg/kg剂量的ASSR连续灌胃Al-loxan诱导的糖尿病小鼠3周,监测血糖,测定体重、血清胰岛素、总胆固醇和甘油三酯水平。结果显示:ASSR的LD50大于9.8 g/kg体重;连续给药3周,ASSR对正常小鼠的血糖和血脂代谢没有明显影响,但能明显降低糖尿病小鼠的血清葡萄糖和甘油三酯水平。上述结果表明:ASSR的LD50大于5 g/kg体重,按WHO急性毒性分级标准属于实际无毒级,其在实验性1型糖尿病小鼠模型上具有降血糖和降甘油三酯活性。     

芦笋老茎澄清汁对链脲佐菌素致糖尿病大鼠降糖作用的研究

本文评价了芦笋老茎澄清汁(CAJ)的降血糖作用,并对其降血糖机制进行了初步探讨。腹腔注射STZ制备类似1型糖尿病大鼠模型,以0.6,1.2和2.0 g/kg体重剂量的CAJ连续灌胃21 d,监测血糖,测定糖化血清蛋白、血清胰岛素、肝糖原、脂代谢及抗氧化系统部分相关指标。结果显示,CAJ可明显降低糖尿病大鼠血清中葡萄糖、糖化血清蛋白、总胆固醇和MDA含量,并显著提高受试模型鼠的血清胰岛素水平、肝糖原含量、血清SOD活性、肝脏SOD、GSH-Px和CAT的活性。上述结果表明CAJ可明显降低糖尿病大鼠的血糖水平,刺激胰岛素分泌,调节血脂,增强抗氧化能力。     

金耳菌丝体多糖对实验性2型糖尿病大鼠的降血糖作用研究

本文研究了金耳菌丝体多糖(TMP)对实验性2型糖尿病大鼠血糖、血脂、胰岛素敏感性和抗氧化能力的影响。采用烟酰胺,链脲佐菌素和高脂饲料诱导2型糖尿病大鼠模型,以50和100mg/(kg.d)剂量的TMP连续灌胃48d,监测血糖,测定血清胰岛素、体重、脂代谢及抗氧化系统部分相关指标,并进行口服糖耐量实验。结果显示,TMP可明显降低2型糖尿病大鼠的血清葡萄糖、总胆固醇、甘油三酯和丙二醛水平,并极显著提高受试模型鼠的胰岛素敏感指数,血清超氧化物歧化酶活性和肝脏过氧化氢酶活性。此外,TMP能显著降低糖耐量实验中糖负荷后120min时糖尿病大鼠的血糖含量。上述结果表明TMP可有效降低实验性2型糖尿病大鼠的血糖水平,纠正脂代谢紊乱,改善胰岛素抵抗,增强抗氧化能力。     

沙棘籽渣多糖对正常及糖尿病模型动物血糖的影响

本文研究了沙棘籽渣多糖(Polysaccharides from seed residue of Hippophae rhamnoide L.,PSH)对正常小鼠及实验性2型糖尿病大鼠血糖、血脂代谢的影响.以100、200和400 mg/kg剂量的PSH连续灌胃正常小鼠20d;以50和100 mg/kg剂量的PSH连续灌胃由烟酰胺联合链脲佐菌素诱导的类似2型糖尿病大鼠3周,测定血糖、糖基化血清蛋白、血清胰岛素、血清总胆固醇、甘油三酯及肝糖原含量.结果显示:PSH对正常小鼠的血糖和血脂代谢没有明显影响;但能明显降低2型糖尿病大鼠的血清葡萄糖、总胆固醇和糖基化血清蛋白水平,同时显著增加糖尿病大鼠的血清胰岛素含量.上述结果表明:PSH在实验性2型糖尿病大鼠模型上具有降血糖和降胆固醇的活性.     

链尿佐菌素加高糖高脂饮食复制大鼠2型糖尿病模型

目的链尿佐菌素加高糖高脂饮食诱导大鼠2型糖尿病模型的建立。方法SD雄性大鼠高糖高脂饲料喂养3周后,采血检测空腹血糖及血清胰岛素,按25mg/g体重剂量一次性腹腔内注射链尿佐菌素,3d后,行糖耐量实验,对糖耐量异常大鼠继续喂以高糖高脂饲料,在第2、第4周再两次采血检测糖尿病鼠空腹血糖及血清胰岛素。结果与对照组比较,高糖高脂喂养大鼠血清胰岛素明显上升（P〈0.01）,但血糖无变化（P〉0.05）,糖尿病鼠血糖及血清胰岛素均显著的高于对照组（P〈0.01）。结论高糖高脂喂养能致大鼠明显的高胰岛素血症,辅以小剂量一次性注射链尿佐菌素而造成的糖耐量异常,可成功复制出2型糖尿病大鼠模型。     

格列吡嗪对2型糖尿病患者血糖、血脂的影响

目的:探讨格列吡嗪对2型糖尿病患者血清血糖及血脂水平的影响.方法:2型糖尿病患者120例.两组年龄、性别匹配,按随机双盲法分为治疗组(60例)和安慰剂组(60例),干预治疗16周后比较其血清血糖和血脂水平,同时测血压、身高、体重等指标,计算体重指数(BMI).结果:经格列吡嗪治疗后,患者血糖、血脂水平明显降低(P＜0.05).结论:格列吡嗪可能通过降低血糖和血脂水平改善2型糖尿病患者胰岛素抵抗从而改善血糖及血脂水平.     

天麦消渴片通过miRNA改善糖尿病大鼠血糖的机制

目的探讨天麦消渴片对糖尿病大鼠体重、血糖、血脂和胰岛素等相关代谢指标的影响,并且利用miRNA表达谱芯片和实时定量RT-PCR探讨天麦消渴片降血糖的机制。方法 SD大鼠通过高脂饮食/注射STZ法构建糖尿病大鼠模型。将SD大鼠分为小剂量天麦消渴片组[8只,给予50 mg/(kg·d)的天麦消渴片粉末悬浊液]、大剂量天麦消渴片组[8只,给予100 mg/(kg·d)的天麦消渴片粉末悬浊液]、糖尿病模型组(8只,给予等体积生理盐水)和正常对照组(8只,给予等体积生理盐水),均连续灌胃8周。每2周测定SD大鼠空腹血糖(FBG)和体重。7周末进行口服糖耐量实验(OGTT),测空腹和葡萄糖负荷后血糖。8周末测定大鼠空腹血糖、血清胰岛素和血脂水平,观察天麦消渴片对糖尿病大鼠血糖和血脂的改善作用。取大鼠胰腺组织进行miRNA表达谱芯片实验,并运用实时定量RT-PCR验证芯片结果,以期探讨天麦消渴片对糖尿病大鼠降血糖的机制。结果干预后,大剂量天麦消渴片组大鼠较糖尿病模型组空腹血糖和OGTT曲线下面积(AUC)显著下降。干预8周后,大剂量天麦消渴片组空腹血清胰岛素(FINS)和胰岛素抵抗指数(HOMA-IR)较糖尿病模型组显著降低(P0.01)。干预8周后,大剂量天麦消渴片组血总胆固醇(TC)和甘油三酯(TG)较糖尿病模型组显著降低(P0.05)。大剂量天麦消渴片组胰腺较糖尿病模型组有18个miRNA上调,3个miRNA下调。结论天麦消渴片不仅能有效降低糖尿病大鼠FBG,改善胰岛素敏感性,还能调节脂代谢。天麦消渴片可能是通过上调胰腺miR-375和miR-30d水平,刺激胰岛β细胞增殖,抑制胰岛α细胞增殖,增加胰岛素基因表达;上调胰腺let-7b、let-7e、miR-142-5p和miR-375,抑制细胞因子及受体相互作用通路和MAPK通路的功能,从而改善糖尿病大鼠血糖和胰岛素抵抗状态。     

罗格列酮联合胰岛素治疗老年2型糖尿病的临床研究

目的 观察罗格列酮联合胰岛素治疗老年2型糖尿病的疗效及安全性.方法 将60例老年2型糖尿病患者随机分为治疗组和对照组各30例,治疗组用罗格列酮4 mg/d,同时加用胰岛素;两组均随访12周,观测血糖、胰岛素用量指标变化及药物的不良反应;对照组单用胰岛素治疗并根据病情调整用量.结果 治疗组血糖水平从第2周开始明显下降,第8～12周血糖水平降幅最大,有21例达到空腹血糖＜6.5 mmol/L,餐后2 h血糖＜8.0 mmol/L的良好控制水平;从第2周开始,治疗组胰岛素用量也逐渐减少,至12周时,治疗组胰岛素用量较基础值减少(7.6±4.3)u;而对照组胰岛素用量却平均增加(9.1±5.1)u.治疗后两组血糖和胰岛素用量比较差异有统计学意义(P＜0.05).结论 罗格列酮联合胰岛素治疗老年2型糖尿病能有效控制患者的血糖水平,且安全,无不良反应.     

沉默长链非编码RNA Meg3损伤小鼠胰岛细胞的胰岛素分泌功能

MEG3是一种长链非编码RNA。已有研究证明,鼠源Meg3参与小鼠诱导多能干细胞、神经元和视网膜的分化过程。最新报道,MEG3在人胰岛β细胞中高表达,但其对维持成年胰岛β细胞的功能尚不清楚。本研究旨在探讨Meg3在小鼠胰岛细胞胰岛素分泌功能中的作用。实时定量PCR揭示,与Balb/c小鼠心、肝、脾、肺、肌、肾等组织/器官比较,Meg3在胰腺组织中高表达。在非糖尿病小鼠发生自发性糖尿病的第8、12周,Meg3在胰岛中的表达水平分别下调24%±8%和29%±9% (P<0.01);而当血糖升高20 mmol/L,小鼠胰岛中Meg3表达下调72%±16%(P<0.01)。在MIN6细胞中采用RNA干扰敲减Meg3的表达,在高糖浓度（20 mmol/L）刺激条件下,胰岛素分泌显著减少。小鼠静脉注射siRNA,结合血糖测定或葡萄糖耐受试验（IPGTT）显示,si-Meg3小鼠血清胰岛素水平显著下降。注射葡萄糖前血糖升高,注射葡萄糖后耐受能力降低;免疫组化分析显示,si-Meg3小鼠胰岛素阳性细胞的面积减少。实验结果提示,Meg3通过参与胰岛素的合成和分泌维持成年小鼠胰岛功能。Meg3表达失调可能参与I型糖尿病（T1DM）发病过程。     

肌肉注射可调控胰岛素基因对糖尿病小鼠降糖作用

为研究四环素调控的胰岛素表达载体肌肉直接注射后对实验性糖尿病小鼠的降糖作用,构建了质粒prTA-tet4-rhINS.以链脲佐菌素(STZ)诱导Balb/C小鼠成糖尿病模型,300 μg质粒注射至小鼠的股部肌肉,并同时在饮水中加入不同浓度强力霉素（Dox）,监测小鼠末梢血糖、体重,测定血清人胰岛素、C肽水平.用RT-PCR检测小鼠肌肉注射部位组织中人胰岛素原mRNA水平的表达情况.结果表明：质粒prTA-tet4-rhINS注射后,给予Dox可显著降低糖尿病小鼠的血糖,血清人胰岛素、C肽水平相应升高,体重增加.效果持续大约二周.小鼠肌肉组织中有人胰岛素原mRNA表达.降糖效果和基因表达程度随Dox浓度增加而增强.质粒prTA-tet4-rhINS对STZ诱导的糖尿病小鼠高血糖起到明显的降低作用.在糖尿病小鼠肌肉组织能很好地表达,并受Dox调控.     

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.