仙茅多糖对氟尿嘧啶增效减毒作用

本文探讨了仙茅多糖(COP)对氟尿嘧啶的增效减毒作用。实验中建立小鼠S180实体瘤模型,连续给药10 d,测定小鼠瘤重,体质量、白细胞、红细胞、胸腺指数、脾脏指数以及小鼠脾脏中的超氧化物歧化酶活性和丙二醛含量。同时建立小鼠S180腹水瘤模型,连续给药30 d,记录小鼠存活天数,计算生命延长率。结果显示,仙茅多糖能改善氟尿嘧啶引起的小鼠白细胞减少、胸腺萎缩、脾脏肿大(P0.05或P0.01);但联用高剂量组使小鼠脾脏中SOD活力(P0.01)降低,联用低、中剂量组使MDA含量增加(P0.05)。COP和5-FU均延长荷瘤小鼠的生存期,(5-FU+COP)联合用药组生命延长率比5-FU单独用药组明显增高,且与联用的COP剂量呈量效关系。从而表明仙茅多糖对氟尿嘧啶具有一定的增效减毒作用,机制可能与其能调节机体免疫力有关,而与过氧化反应无关。     

芪胶升白胶囊联合环磷酰胺对S_(180)荷瘤小鼠增效减毒作用研究

本文探讨芪胶升白胶囊(QSC)与环磷酰胺(CTX)联合应用对S_(180)荷瘤小鼠的增效减毒作用。造荷S_(180)肿瘤小鼠模型,60只荷瘤小鼠随机分为5组:模型组,CTX(30 mg/kg)组,CTX+QSC低、中、高剂量(0.5、1.0、2.0 g/kg)组。每日测量小鼠体重和肿瘤体积,分别连续给药15 d后,测小鼠血细胞计数,脏器指数和抑瘤率,HE染色法观察肿瘤组织形态,Annexin V/PI双染流式术测定肿瘤组织细胞的凋亡率。实验结果显示与CTX组比较,联合用药各剂量组的小鼠肿瘤体积均较小,抑瘤率以及肿瘤细胞凋亡率均有提高,胸腺、脾脏指数也较高,联合用药高剂量组白细胞计数增高统计学意义显著(P0.01),镜下观察肿瘤组织坏死明显,表明QSC与CTX联合使用对S_(180)荷瘤小鼠有一定的增效减毒作用。     

凤丹籽油对小鼠H22肿瘤的抑制作用

探讨凤丹籽油对小鼠移植性肿瘤H22的抑瘤作用及机制。建立肝癌H22移植性肿瘤模型小鼠,随机分为正常组、模型组、5-氟尿嘧啶(5-FU)阳性对照组、凤丹籽油高、中、低剂量组,给药10 d后处死。结果表明:低、中、高剂量组的抑瘤率分别是18.4%、26.9%、34.7%,具有较好量效关系。与模型组相比,低、中、高剂量组能不同程度提高胸腺、脾脏指数,降低AST、ALT、ALP,增加WBC;降低TE活性和BCL-2表达,显著提高BAX表达。以上结果表明,高剂量凤丹籽油对H22荷瘤小鼠有明显的抑瘤作用,其机制可能是通过调节免疫功能和抑制TE活性、BCL-2表达,提高BAX表达而发挥肿瘤抑制作用。     

重组别藻蓝蛋(rAPC)抑瘤活性及其对免疫作用的研究

目的:观察重组别藻蓝蛋白(rAPC)对接种H22肝癌细胞小鼠的抑瘤活性及其免疫作用.方法:昆明小鼠随机分为5组(10只/组),即模型组、rAPC低、中、高剂量组(25,50,100mg/kg·d)、环磷酰胺组(CY对照组).建立小鼠肝癌1422移植瘤模型,次日除模型组外,其余4组分别以不同剂量的rAPe、CY灌胃,于15d后处死,完整剥离出肿瘤、胸腺、脾脏,准确称重,计算抑瘤率、胸腺指数和脾指数,并采用放免法(PIA)测定血清中白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)的水平.结果:rAPC低剂量组小鼠H22肿瘤质量增长较模型组缓慢(P＜0.05),中、高剂量组较模型组显著缓慢(P＜0.01),抑瘤率分别为25.2%、36.7%、43.1%;rAPC各剂量组能升高胸腺指数、脾指数和血清中细胞因子IL-6、TNF-α的水平.结论:rAPC可有效抑制H22肝癌的生长,促进小鼠胸腺和脾脏的生长发育,提高小鼠的免疫功能,从而抑制肿瘤的生长.     

刺参酸性粘多糖对H22肝癌小鼠免疫功能的影响(英文)

目的:刺参酸性粘多糖作为一种天然生物活性物质,具有较强抗肿瘤作用。本研究观察刺参酸性粘多糖对荷瘤小鼠免疫功能的影响,以探讨刺参酸性粘多糖的抗肿瘤作用机制。方法:皮下接种H22小鼠肝癌细胞,建立移植瘤小鼠模型。将50只荷瘤小鼠随机分为五组(阴性对照组、氟尿嘧啶组、SJAMP低剂量组、SJAMP中剂量组、SJAMP高剂量组),腹腔注射不同剂量刺参酸性粘多糖,每日一次,连续12天。眼球摘除取血后颈椎脱臼处死小鼠,计算抑瘤率和脏器指数,中性红法测定小鼠腹腔巨噬细胞吞噬功能,CCK-8法测定小鼠脾淋巴细胞增殖能力,ELISA法测定小鼠血清TNF-α水平。结果:SJAMP能够明显抑制肿瘤生长(P0.05);与5-FU组相比,SJAMP干预组脾指数和胸腺指数明显升高(P0.05),腹腔巨噬细胞吞噬能力和脾脏淋巴细胞增殖功能显著提高(P0.05),TNF-α的血清含量显著减少(P0.05)。结论:刺参酸性粘多糖通过促进免疫器官生长,增强机体的免疫功能,抑制小鼠H22肝癌生长。这为SJAMP的抗肿瘤作用研究提供了试验依据和理论基础。     

重组别藻蓝蛋白(rAPC)抑瘤活性及其对免疫作用的研究(英文)

目的:观察重组别藻蓝蛋白(rAPC)对接种H22肝癌细胞小鼠的抑瘤活性及其免疫作用。方法:昆明小鼠随机分为5组(10只/组),即模型组、rAPC低、中、高剂量组(25,50,100mg/kg·d)、环磷酰胺组(CY对照组)。建立小鼠肝癌H22移植瘤模型,次日除模型组外,其余4组分别以不同剂量的rAPC、CY灌胃,于15d后处死,完整剥离出肿瘤、胸腺、脾脏,准确称重,计算抑瘤率、胸腺指数和脾指数,并采用放免法(RIA)测定血清中白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)的水平。结果:rAPC低剂量组小鼠H22肿瘤质量增长较模型组缓慢(P<0.05),中、高剂量组较模型组显著缓慢(P<0.01),抑瘤率分别为25.2%、36.7%、43.1%;rAPC各剂量组能升高胸腺指数、脾指数和血清中细胞因子IL-6、TNF-α的水平。结论:rAPC可有效抑制H22肝癌的生长,促进小鼠胸腺和脾脏的生长发育,提高小鼠的免疫功能,从而抑制肿瘤的生长。     

双歧杆菌脂磷壁酸与5-氟尿嘧啶联用的抗肿瘤研究

目的探讨双歧杆菌脂磷壁酸与5-氟尿嘧啶（5-Fu）联用对H22荷瘤小鼠的抗肿瘤作用及免疫功能的影响。方法双歧杆菌脂磷壁酸单独或联合5-Fu处理H22荷瘤Balb／c小鼠,定期测量肿瘤大小,观察小鼠一般状况;计算抑瘤率、血红细胞数和白细胞数,取脾和胸腺计算脏器指数;HE染色分析肿瘤组织变化;MTT法检测小鼠脾T淋巴细胞增殖转化功能以及ELISA法检测小鼠脾淋巴细胞分泌IFN-γ含量。结果双歧杆菌脂磷壁酸及5-Fu单独应用均可抑制肿瘤生长,但单独5-Fu处理组小鼠一般状况差,毒性反应重;双歧杆菌脂磷壁酸与5-Fu联合应用,与单独5-Fu处理组比较,不仅抑瘤率明显提高（P〈0．01）,且荷瘤小鼠一般状况改善,白细胞数升高,脏器指数增加,小鼠脾T淋巴细胞增殖能力强,脾淋巴细胞分泌IFN-γ,水平提高;光镜观察HE染色瘤体组织,双歧杆菌脂磷壁酸处理组可见大量炎症细胞浸润。结论双歧杆菌脂磷壁酸联合5-FU能增强化疗的抑瘤作用,并能扭转化疗引起的免疫低下现象,起到增效减毒作用。     

人参多糖对环磷酰胺的增效减毒作用

目的探讨人参多糖（ginseng polysaccharide,GPS）对化疗药物环磷酰胺（cyclophosphamide,CTX）抗肿瘤的增效减毒作用。方法建立小鼠肝癌H22实体瘤模型,随机分组,设模型对照组（生理盐水）、环磷酰胺组（30 mg/kg）、人参多糖给药组（7.5、15、30 mg/kg剂量组）和联合给药组（GPS 7.5、15、30 mg/kg,CTX 30 mg/kg）;人参多糖尾静脉注射,CTX腹腔给药,连续给药10 d;测定抑瘤率、血液学指标、脾脏系数和胸腺系数,评价人参多糖对环磷酰胺的增效减毒作用。结果 GPS、GPS＋CTX各组肿瘤生长明显低于模型对照组（P〈0.01）,GPS中、高剂量＋CTX联合给药组肿瘤生长明显低于CTX组（P〈0.05,P〈0.01）。GPS高剂量＋CTX组与CTX组相比,体重、脾脏指数和胸腺指数明显升高（P〈0.05）。结论人参多糖对化疗药物环磷酰胺抗小鼠肝癌H22肿瘤具有增效减毒作用。     

双歧杆菌脂磷壁酸与5-氟尿嘧啶体内联用对肿瘤细胞凋亡的影响

目的研究双歧杆菌脂磷壁酸与5-氟尿嘧啶联用诱导H22荷瘤小鼠肿瘤细胞凋亡的作用机制。方法双歧杆菌脂磷壁酸联合5-FU处理H22荷瘤Balb/c小鼠,计算抑瘤率,观察小鼠生存期;采用Real time-PCR和Western blot方法分别检测荷瘤小鼠肿瘤组织Bcl-2、Bax和Caspase-3 mRNA及蛋白的表达变化。结果双歧杆菌脂磷壁酸联合5-FU应用,与单独5-FU处理组比较,不仅抑瘤率明显提高（P〈0.01）,且荷瘤小鼠存活时间明显延长（P〈0.01）,肿瘤组织Bcl-2表达下降,Bax和Caspase-3表达升高（P〈0.05）。结论双歧杆菌脂磷壁酸联合5-FU可通过上调Bax和Caspase-3,下调Bcl-2,促进肿瘤细胞凋亡,从而发挥协同抗肿瘤作用。     

广叶绣球菌超微粉抗肿瘤作用研究

广叶绣球菌(荷仙菇-H)是近年来新培养的一种食药用真菌,属担子菌门、多孔菌目、绣球菌科、绣球菌属。本文对其超微粉的抗肿瘤作用及机制进行了研究。建立了H22荷瘤小鼠肿瘤移植模型,设置空白对照组、模型组、环磷酰胺阳性组、广叶绣球菌超微粉高、中、低3个剂量组(1 000,500和100mg/kg),连续给予相应药物10d,计算H22荷瘤小鼠的抑瘤率、体质量、胸腺指数、脾脏指数以及肝脏指数,对各组小鼠的瘤块进行组织病理学研究,并对血清中的SOD和IFN-γ含量进行了测定。结果发现广叶绣球菌超微粉3个给药组的抑瘤率均大于40%,高剂量组抑瘤率最高为54%;可增加小鼠体质量;提高胸腺指数、脾脏指数和肝脏指数;给药组SOD值均高于模型组,说明广叶绣球菌超微粉可以起到抗氧化的作用;给药组IFN-γ值均高于模型组,给药组VEGF值均低于模型组,说明广叶绣球菌超微粉能够提高机体免疫能力。因此,广叶绣球菌超微粉的抗肿瘤作用明显,可能是通过改善机体免疫功能和抗氧化能力,抑制了肿瘤细胞,达到抗肿瘤的功效。     

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).