多肽铬螯合物对糖尿病小鼠肝脏蛋白质表达的影响

目的:研究多肽铬螯合的对糖尿病小鼠肝脏蛋白质表达的影响,探讨其治疗糖尿病的机理.方法:通过腹腔注射四氧嘧啶建立糖尿病小鼠模型.将小鼠分为正常组、模型组和胶铬组,胶铬组以灌胃方式加入多肽铬螯合物;以光镜及HE染色观察三组小鼠肝脏形态及组织学的变化,采用SDS-PAGE实验和非SDS-PAGE检测三组小鼠肝脏蛋白质表达.结果:光镜及组织学观察结果显示多肽铬螫合物可以有效地减轻四氧嘧啶对肝细胞造成的损伤.模型组肝脏25kDa-35kDa之间的某种蛋白表达升高而多肽铬螯舍物可以降低此种蛋白的表达,初步推断这种蛋白质为SOD.结论:多肽铬螯合物能够通过降低四氧嘧啶造成的肝脏中抗氧化有关的蛋白质代偿性升高而祈祷保护肝脏的作用,是一种新型的治疗糖尿病所致的肝损伤的活性物质.     

多肽铬螯合物对糖尿病小鼠肝脏蛋白质表达影响的研究

目的：研究多肽铬螯合物对糖尿病小鼠肝脏蛋白质表达的影响,探讨其治疗糖尿病的机理。方法：通过腹腔注射四氧嘧啶建立糖尿病小鼠模型。将小鼠分为正常组模型组和胶铬组,胶铬组以灌胃方式加入多肽铬螯合物;以光镜及HE染色观察三组小鼠肝脏形态及组织学的变化,采用SDS-PAGE实验和非SDS-PAGE检测三组小鼠肝脏蛋白质表达。结果：光镜及组织学观察结果显示多肽铬螯合物可以有效地减轻四氧嘧啶对肝细胞造成的损伤。模型组肝脏25kDa-35kDa之间的某种蛋白表达升高而多肽铬螯合物可以降低此种蛋白的表达,初步推断这种蛋白质为SOD。结论：多肽铬螯合物能够通过降低四氧嘧啶造成的肝脏中抗氧化有美的蛋白盾代偿性升高而起到保护肝脏的作用．是一种新型的治疗糖尿痛所致的肝损伤的活性物盾。     

胶原蛋白多肽-铬（Ⅲ）螯合物对糖尿病小鼠免疫力的影响

目的研究胶原蛋白多肽-铬（Ⅲ）（CPCC）螯合物对由四氧嘧啶诱发糖尿病小鼠的免疫力的影响。方法通过腹腔注射四氧嘧啶造小鼠糖尿病模型,观察胶原蛋白多肽-铬（Ⅲ）螯合物对小鼠血糖、脾指数、胸腺指数、脾细胞增殖能力、NK细胞杀伤活性、CD40、CD40L的表达等指标的影响。结果胶原蛋白多肽-铬（Ⅲ）螫合物可以有效预防小鼠血糖升高,对脾指数、胸腺指数有一定的恢复作用,脾细胞增殖能力明显增强,NK细胞的杀伤活性被提高,CD40、CD40L的阳性表达率增加。结论胶原蛋白多肽-铬（Ⅲ）能活化免疫细胞,恢复和改善小鼠机体的免疫功能,提高小鼠机体的免疫力,一定程度地减轻四氧嘧啶的毒性作用,降低血糖。     

硒酸赖氨酸对四氧嘧啶诱发的小鼠肝损伤的防护作用

目的:研究硒酸赖氨酸对四氧嘧啶诱发的小鼠肝损伤的防护作用。方法:选取昆明小鼠50只,雌雄各半,随机分成五组,即对照组、模型组、低剂量组、中剂量组、高剂量组。采用四氧嘧啶致急性肝损伤模型,检测各组小鼠血清中谷丙转氨酶(ALT)、谷草转氨酶(AST)、碱性磷酸酶(AKP)活性,并对各组小鼠肝脏进行组织病理学观察。结果:硒酸赖氨酸能降低小鼠血清中ALT、AST、AKP活性(P<0.05或P<0.01),明显减轻四氧嘧啶致肝损伤小鼠肝细胞的病变及炎症反应。结论:硒酸赖氨酸具有对四氧嘧啶诱发小鼠肝损伤的保护作用。     

虾青素对四氧嘧啶致糖尿病小鼠降血糖作用研究

为研究天然虾青素在四氧嘧啶致糖尿病小鼠体内的降血糖作用,将天然虾青素分为高、中、低3个剂量组给四氧嘧啶致糖尿病小鼠灌胃,以0．9％生理盐水为模型对照,以二甲双胍为阳性药物对照进行实验。结果表明：三个剂量的天然虾青素均能较好的降低四氧嘧啶致糖尿病小鼠的血糖水平,并能减缓糖尿病小鼠消瘦和多饮多食的症状,以高剂量组的效果最佳。进一步考察了高剂量的虾青素对正常小鼠的影响,发现其对正常小鼠血糖无显著影响。虾青素对四氧嘧啶致糖尿病小鼠具有明显的降血糖作用。     

壳寡糖螯合铬对糖尿病小鼠降血糖作用的研究

探讨壳寡糖螯合铬(Cos-Cr)的降血糖作用。选择发育相近的健康雄性小鼠10只为正常对照组,糖尿病小鼠30只随机分为糖尿病对照组、壳寡糖组(Cos)和螯合铬组(Cos-Cr),每组各10只,实验期4 w,测定小鼠血糖值。壳寡糖螯合铬可以降低糖尿病小鼠血糖,增加体重,增加脾脏指数,明显缓解糖尿病小鼠饥饿和烦渴的症状。肝脏损伤明显减轻。同时观察肝组织病理变化。壳寡糖螯合铬对糖尿病小鼠有降糖,改善糖尿病症状的作用。     

番石榴多糖对糖尿病小鼠的血糖及胸腺、脾指数的影响

研究采用两种不同方法提取的番石榴多糖对四氧嘧啶致糖尿病的小鼠血糖值及胸腺、脾指数的影响。通过给小鼠腹腔注射四氧嘧啶(200 mg/kg BW)建立糖尿病小鼠模型,尾端取血,采用血糖仪分别在给小鼠灌胃多糖三天和十天后检测小鼠血糖值,第十天解剖小鼠,分别对小鼠胸腺和脾脏称重。结果表明:与糖尿病对照组比较,两组灌喂番石榴多糖的小鼠的生存质量提高,血糖值显著降低,同时胸腺指数显著增加,提示番石榴多糖具有降血糖作用,是一种潜在的糖尿病治疗药物。     

野生地参多糖对四氧嘧啶致糖尿病小鼠血糖和血脂的影响

为了研究野生地参多糖对四氧嘧啶(ALX)致糖尿病小鼠血糖和血脂的影响,利用四氧嘧啶(ALX)建立糖尿病小鼠模型,分别灌胃低(100 mg/(kg.d))、中(200 mg/(kg.d))、高(400 mg/(kg.d))剂量地参多糖溶液及阳性对照药盐酸苯乙双胍,正常对照组及糖尿病模型对照组则给等体积生理盐水。结果表明:连续给药14 d后,地参多糖对正常小鼠血糖无明显影响,100、200和400 mg/(kg.d)地参多糖均能明显降低ALX所致糖尿病小鼠高血糖,与糖尿病模型对照组相比,P<0.01;同时,相同剂量的地参多糖还能极显著降低ALX致糖尿病小鼠血清总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)(P<0.01)。中、高剂量地参多糖使糖尿病小鼠血清高密度脂蛋白胆固醇(HDL-C)显著回升(P<0.05),但低剂量地参多糖对糖尿病小鼠血清HDL-C则无明显影响(P>0.05)。地参多糖能明显降低ALX致糖尿病小鼠高血糖及高血脂。     

胰岛素对糖尿病大鼠代谢紊乱的调节作用

利用四氧嘧啶建立糖尿病大鼠模型,研究了胰岛素对糖尿病大鼠脂肪、蛋白质、自由基代谢紊乱的调节作用及对机体和肝脏氧化损伤的保护作用。结果表明,胰岛素0．5U/kg皮下注射8周,能明显抑制糖尿病引起大鼠体重的降低。皮下注射6周,显著提高了血清总蛋白、白蛋白、总胆固醇的水平,降低了血清甘油三酯的含量。胰岛素1U／kg皮下注射9d,能显著提高血清超氧化物歧化酶、谷肮甘肽过氧化物酶的活性,降低血清丙二醛的含量及促氧化酶黄嘌呤氧化酶的活性,提高肝线粒体谷胱甘肽过氧化物酶的活性,降低肝线粒体丙二醛的含量。从而调节糖尿病大鼠脂肪、蛋白质、自由基代谢紊乱,减轻机体的氧化损伤,改善肝功能。     

桦褐孔菌与松口蘑菌粉降血糖作用的研究

为评价桦褐孔菌和松口蘑发酵菌粉的降血糖作用,本文观察了经不同浓度桦褐孔菌和松口蘑菌粉溶液灌胃后,小鼠正常血糖、给予葡萄糖小鼠以及四氧嘧啶糖尿病小鼠血糖的变化.结果表明:桦褐孔菌、松口蘑菌粉溶液(500、1000 mg/kg)对小鼠正常血糖值、正常小鼠糖耐量没有明显影响(P>0.05);对于糖尿病小鼠血糖,桦褐孔菌低剂量组(500 mg/kg)和桦褐孔菌高剂量组(1000 mg/kg)的降糖效果较为明显(P<0.01),用药前与用药后第21 d的血糖值分别为(14.94±1.85)、(10.43±2.22)和(14.89±1.65)、(10.17±2.14) mmol/L,降糖率分别为30.23% 和31.7%.桦褐孔菌和松口蘑菌粉对于小鼠正常血糖、正常小鼠糖耐量无明显影响,对于四氧嘧啶糖尿病小鼠具有一定的降血糖效果.     

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.     

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     

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.     

鸡传染性法氏囊病病毒研究进展

传染性法氏囊病(Infection bursal disease, IBD)是由鸡传染性法氏囊病毒(Infectious bursal disease virus, IBDV)引起的鸡和火鸡的一种高度接触性传染病,给世界各国的禽养殖业带来了巨大损失.自IBDV发现至今新的变异株不断出现,分子结构的改变导致病毒致病力的改变及宿主对疫苗应答的改变,使得传统的疫苗已不能控制其流行,因此各国学者对其基因组结构和功能进行了广泛深入的研究,并积极研制新型有效的疫苗以达到防治的目的.     

Development of a Novel Reverse Transcription Loop-Mediated Isothermal Amplification Method for Rapid Detection of SARS-CoV-2

In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.     

Perinatal Vertical Transmission of Chikungunya Virus in Ruili,a Town on the Border between China and Myanmar

正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).     

Enterovirus 71 3C proteolytically processes the histone H3 N-terminal tail during infection

Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.