松子壳多糖对小鼠主要免疫细胞功能的影响

目的探讨松子壳多糖（pine nut shell polysaccharide,PSP）对小鼠主要免疫细胞的影响。方法应用MTT法测定PSP对小鼠脾淋巴细胞的毒性和对ConA或LPS诱生小鼠脾T、B淋巴细胞的转化,用中性红吞噬试验测定腹腔巨噬细胞的吞噬功能,应用乳酸脱氢酶释放法测定NK细胞的杀伤活性。结果 PSP对脾细胞毒性很低,各种浓度对小鼠脾淋巴细胞的增殖均有较强的促进作用（P〈0.01）;PSP在浓度50～300μg/mL时,明显促进T淋巴细胞的转化（P〈0.01）,但是当浓度达到300μg/mL时表现出一定的抑制作用（P〉0.05）;PSP在25～200μg/mL时显著促进了小鼠脾B淋巴细胞的转化（P〈0.05）,但是当浓度达到300μg/mL时,抑制作用极显著（P〈0.01）;不同浓度均可以增强小鼠腹腔巨噬细胞吞噬中性红的能力及其代谢功能,当浓度在100μg/mL时能显著的促进巨噬细胞吞噬中性红的能力（P〈0.01）;PSP在浓度100～300μg/mL时,能极显著的促进NK细胞对Yac-1的杀伤作用（P〈0.01）,当浓度达到400μg/mL,对NK细胞杀伤性的促进作用开始减弱。结论 PSP对小鼠脾淋巴细胞的毒性较低,能增强免疫细胞活性,有望成为新一代免疫调节剂。     

海胆黄多糖SEP对S180的体内抑制作用

研究海胆黄多糖SEP对S180肉瘤的抑制作用及初步机制。MTT法检测SEP对体外培养的S180细胞生长的抑制作用;建立小鼠S180肉瘤模型观察SEP抗肿瘤活性;检测SEP协同ConA/LPS刺激小鼠脾淋巴细胞增殖作用;同时,考察SEP对NK细胞和杀伤性T淋巴细胞(cytotoxic T lym-phocyte,CTL)活性的影响;碳粒廓清检测SEP对小鼠单核巨噬细胞吞噬功能的影响。研究表明,海胆黄多糖SEP高中低剂量(16、8、4 mg/kg)显著抑制小鼠180实体瘤生长,增加小鼠脾指数和胸腺指数,协同ConA/LPS刺激小鼠脾淋巴细胞增殖,提高小鼠NK细胞和CTL活性,增强小鼠单核巨噬细胞的吞噬功能,通过免疫调节提高小鼠免疫功能达到抑制S180作用。     

体内外感染PRRSV处理下仔猪脾淋巴细胞增殖活性的变化

为了探讨体内或体外感染猪繁殖与呼吸综合征病毒(porcine reproductive and respiratory syndrome virus,PRRSV)的仔猪脾淋巴细胞在体外培养的增殖能力,本研究将PRRSV-GXA分离株经Marc-145细胞大量增殖培养,然后体内感染仔猪,接种病毒后分别于第11天、第14天和第21天从活体猪收获脾脏,分离脾淋巴细胞后用ConA和LPS于体外进行诱导增殖.研究结果显示第11天收获的T淋巴细胞增殖能力高于对照组,而B淋巴细胞增殖能力明显下降;第14天收获的T淋巴细胞和B淋巴细胞的增殖能力均极显著低于对照组;第21天收获的B淋巴细胞增殖能力略高于对照组,T淋巴细胞增殖能力略低于对照组.同时,用不同滴度的PRRSV体外感染PRRSV阴性的猪脾淋巴细胞,经ConA和LPS诱导增殖后,发现病毒滴度在103~106 TCID50/mL范围内,能明显提高脾淋巴细胞的体外增殖能力;而病毒滴度在100~102 TCID50/mL范围时,脾淋巴细胞增殖能力低于对照组.本研究结果说明PRRSV体内或体外感染对仔猪脾淋巴细胞增殖活性均有显著的影响,将为临床上PRRS的综合防治提供理论依据.     

黄鳍金枪鱼头蛋白酶解液及分级组分对小鼠脾淋巴细胞增殖的影响

研究黄鳍金枪鱼头蛋白酶解液(EPTH)及截留相对分子量(MWCO)10、5、3和1 kD的超滤分级组分Ⅰ(10 kD)、组分Ⅱ(10～5 kD)、组分Ⅲ(5～3 kD)、组分Ⅳ(3～1 kD)和组分Ⅴ(1 kD)对小鼠脾淋巴细胞增殖的影响。采用无菌分离小鼠脾淋巴细胞,MTT法检测EPTH及各分级组分对有和没有刀豆蛋白A(ConA)、脂多糖(LPS)诱导下脾淋巴细胞增殖的影响,半微量凯氏定氮法、测定EPTH及各分级组分的氮含量。结果显示组分Ⅱ、组分Ⅴ单独作用能明显促进淋巴细胞增殖,并显著促进ConA、LPS诱导的淋巴细胞增殖;EPTH及其余3组分均没有显著的促进或抑制作用。组分Ⅱ、组分Ⅴ富集了促进小鼠脾淋巴细胞增殖的因子;组分Ⅱ、组分Ⅴ蛋白质含量分别占EPTH的38.9%和5.39%。     

豆腐柴根提取物对小鼠T淋巴细胞增殖反应的影响

利用3H-TdR放射性来测定T淋巴细胞增殖强度的方法,研究了豆腐柴根提取物对小鼠T淋巴细胞增殖反应的影响.结果表明,豆腐柴根提取物在一定浓度范围内可促进刀豆蛋白(ConA)诱导T淋巴细胞发生增殖反应,其中2μg.mL-1提取物浓度效果最为明显.该研究为合理开发利用豆腐柴这一野生药物资源提供了科学的实验依据.     

大鼠杏仁核5-HT_3受体参与免疫调制

实验通过大鼠侧脑室和杏仁核给予 5 HT3受体激动剂 1 phenylbiguanide (PBG) ,用 3H TdR掺入法测定脾细胞丝裂原 (concanavalinA ,ConA和lipopolysaccharide ,LPS)刺激增殖效应 ,用活化脾细胞增殖法测定IL 2生成 ,MTT法测定自然杀伤 (naturalkiller,NK)细胞活性和用放射免疫测定血浆皮质酮水平 ,以探讨大鼠杏仁核 5 HT3受体在免疫调控中的作用。结果表明 :5 HT3受体拮抗剂granisetron (GNT ,0 1～ 0 4mg/kgip)剂量依赖地增强ConA和LPS刺激的脾细胞增殖 ,作用在连续给药 5d最明显 ;双侧脑室给予PBG ( 5 μg/side)可增强ConA和LPS刺激的脾细胞增殖效应 ,作用在连续给药 3d最明显 ;双侧和单侧中央杏仁核给予PBG 0 5 μg均增强ConA刺激的脾细胞增殖和IL 2生成 ;底内侧杏仁核给予同剂量PBG仅增强LPS刺激的脾细胞增殖效应 ,不影响ConA刺激的脾细胞增殖和IL 2生成 ;中央杏仁核给予PBG升高血浆皮质酮的作用较底内侧杏仁核给予等量PBG引起的升高血浆皮质酮作用明显 (P <0 0 1)。侧脑室、中央杏仁核和底内杏仁核给予PBG对丝裂原刺激的脾细胞增殖效应影响不同 ,但均被同时同部位给予GNT所拮抗 ,提示杏仁核中央核和底内侧核的 5 HT3受体可能以不同方式参与ConA或LPS刺激的脾细胞增殖效应的调制     

连翘酯苷对小鼠脾脏淋巴细胞体外增殖与分泌功能的影响

目的分析连翘酯苷（FS）对小鼠脾脏T和B淋巴细胞增殖、分泌NO和TNF-α的影响,初步探讨其免疫调节作用机制。方法无菌操作分离小鼠脾脏,制备脾脏细胞并用含10%胎牛血清的RPMI 1640培养,在培养液中分别加入刺激剂刀豆蛋白（ConA）和脂多糖（LPS）以及不同浓度40、80、160μg/mL的FS共培养不同时间,采用MTT法检测T和B淋巴细胞的吸光度变化,ELISA和Griess法分别检测细胞分泌TNF-α和NO的水平。结果低浓度和中浓度FS对ConA诱导T淋巴细胞24 h和48 h后细胞增殖和存活率明显提高,诱导时间延长至72 h后FS明显抑制细胞转化;低浓度FS对LPS诱导脾脏B淋巴细胞24 h后细胞增殖和生存率显著提高;FS促进小鼠脾脏T和B淋巴细胞分泌NO;FS促进B淋巴细胞分泌TNF-α,中浓度FS促进T淋巴细胞分泌TNF-α而高浓度反而抑制其分泌。此外,FS对环磷酰胺（CY）处理小鼠的脾脏淋巴细胞体外增殖有明显影响,对细胞NO分泌影响不显著。结论结果提示FS可能通过影响小淋巴细胞增殖和细胞因子分泌而调节免疫细胞功能。     

顺天胶囊对小鼠免疫功能的影响

本文探讨了顺天胶囊(Shun Tian Capsule;STC)在体外对小鼠淋巴免疫功能的影响,实验结果表明,本品浓度在0.25～1.0μml~(-1)范围内明显促进ConA和LPS对淋巴细胞增殖反应,增强诱导淋巴细胞产生IL-2和INF-α。提示,本品具有明显增强免疫功能的作用,最适剂量为0.5～0.75 ug.ml~(-1),并呈浓度依赖性的双向作用。     

脂多糖对多发性骨髓瘤细胞增殖的影响及其机制

目的:探讨脂多糖(lipopolysaccharide,LPS)对多发性骨髓瘤细胞增殖的影响及其作用机制。方法:采用LPS作用于多发性骨髓瘤细胞RPMI 8226后,通过MTT法检测细胞的增殖情况,流式细胞术检测细胞周期的变化,Western blot检测NF-κB信号通路中相关蛋白p65和IκB-α的表达情况。结果:随着LPS作用浓度(0-8μg/mL)的增加,RPMI 8226细胞增殖活力呈先上升后下降的趋势,在2μg/m L LPS作用下,RPMI8226细胞的增殖活力最显著(P0.05)。相同浓度的LPS诱导RPMI8226细胞不同时间,其细胞增殖呈时间依赖性。流式细胞术检测结果显示:不同浓度LPS(0.5、1、2μg/mL)作用RPMI 8226细胞后,G0/G1期细胞的比例明显低于对照组(P0.05),S期和G2/M期细胞比例明显增加(P0.05);Western blot检测结果显示:2μg/mL的LPS处理的RPMI8226细胞p65和IΚB-α蛋白的表达明显高于对照(P0.05)。结论:低浓度LPS能够诱导多发性骨髓瘤细胞RPMI 8226的增殖,其作用机制可能与上调信号通路NF-κB中相关蛋白p65和IκB-α有关。     

透明质酸孵育树突状细胞对荷瘤小鼠免疫功能的影响

目的：研究透明质酸对小鼠骨髓来源树突状细胞功能的影响以及回输后荷黑色素瘤小鼠脾淋巴细胞增殖、活化和细胞因子 的变化,进而探讨透明质酸诱导的树突状细胞增强荷瘤小鼠免疫功能的机制。方法：体外细胞因子联合诱导培养小鼠骨髓细胞获 得树突状细胞（DCs）,免疫磁珠分选纯化获得CD11c+树突状细胞,经不同浓度透明质酸（HA）刺激后,采用酶联免疫吸附法 （ELISA）检测培养上清液中细胞因子IL-12p70 含量。建立小鼠皮下B16 黑色素瘤模型,肿瘤局部皮下回输HA 孵育DC后检测 肿瘤大小,应用ConA 检测脾淋巴细胞增殖情况,应用MTT 法检测脾淋巴细胞杀伤活性,ELISA 法检测脾淋巴细胞分泌的 TNF-alpha和IFN-r的表达,以单纯DC回输、生理盐水注射以及正常小鼠（无瘤）组作为对照。结果：在10～100 ug/mL 范围内,HA 以剂量依赖的方式上调DCs 分泌IL-12p70。HA 孵育DC处理组肿瘤生长明显受到抑制;淋巴细胞增殖反应、杀伤活性和细胞因 子TNF-alpha和IFN-r的表达明显高于单纯DC 组和生理盐水组(P < 0.05)。结论：透明质酸可促进小鼠骨髓DC 的成熟;透明质酸孵 育的DC 通过增强荷瘤小鼠的抗肿瘤免疫功能而抑制肿瘤的生长。     

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.     

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.     

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.     

Detection of EBV and HHV6 in the Brain Tissue of Patients with Rasmussen’s Encephalitis

Rasmussen’s encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8⁺ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8⁺ T cells are involved in the pathogenesis of RE.     

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).     

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.