齐墩果酸抑制肿瘤坏死因子-α诱导的成纤维细胞样滑膜细胞炎症因子表达及其机制研究

探讨齐墩果酸(Oleanolic acid,OA)对肿瘤坏死因子-α(TNF-α)诱导成纤维细胞样滑膜细胞的炎症因子表达的影响及其机制。首先复苏培养人成纤维细胞样滑膜细胞(FLS),通过RT-PCR检测细胞IL-6及IL-1βmRNA表达,采用Western blot方法检测p38MAPK及NF-κB蛋白表达变化,通过ELISA法检测细胞上清液中IL-6及IL-1β浓度。与对照组比较,TNF-α明显诱导FLS细胞IL-6及IL-1βmRNA的表达及上清液中IL-6及IL-1β的分泌(P0.05),同时磷酸化p38蛋白和核NF-κB明显增加(P0.05),且p38MAPK阻断剂SB203580能抑制TNF-α诱导的核NF-κB增加。OA呈浓度依赖性抑制TNF-α诱导的FLS细胞p38蛋白磷酸化和核NF-κB增加(P0.05)。且OA、p38MAPK通路抑制剂SB203580或NF-κB阻断剂BAY 11-7082均能抑制TNF-α诱导的IL-6及IL-1β分泌增加(P0.05)。综上所述,OA能抑制TNF-α诱导的FLS细胞炎症因子IL-6及IL-1β的产生,其机制可能与抑制p38MAPK/NF-κB信号通路有关。     

EGb761对LPS诱导THP-1细胞释放HMGB1蛋白表达的调节

目的:探讨EGb761对LPS诱导THP-1细胞释放HMGB1蛋白表达的调节,为EGb761的临床运用提供可行的依据。方法:LPS(1μg/m L)诱导不同时间后,western blotting检测THP-1细胞上清液中HMGB1蛋白含量变化及不同浓度EGb761对LPS诱导THP-1细胞释放HMGB1蛋白的表达和NF-κB的活性;酶联免疫吸附法(ELISA)检测细胞中IL-1β、IL-6、TNF-α的含量。共聚焦显微镜观察EGb761对LPS诱导THP-1细胞释放HMGB1蛋白核转位变化。结果:(1)LPS组IL-1β、IL-6、TNF-α的含量在刺激6-12 h后明显高于空白对照组,而EGb761+LPS组IL-1β、IL-6、TNF-α的含量均显著低于LPS组(P0.05)。(2)EGb761处理LPS诱导THP-1细胞6 h后细胞上清液NF-κB活性表达量较空白对照组低,随着处理时间延长至12 h,NF-κB的活性表达量呈明显下降趋势(P0.05)。(3)LPS诱导THP-1细胞18 h后,细胞上清液中HMGB1蛋白含量呈明显升高趋势(P0.05)。(4)不同浓度EGb761对LPS诱导THP-1细胞18 h后,HMGB1蛋白含量较空白对照组有下降趋势,HMGB1蛋白含量随着EGB761浓度增加至100μg/m L呈下降趋势并呈浓度依赖效应(P0.05)。(5)LPS诱导THP-1细胞后,在共聚焦显微镜下可见胞浆中大量HMGB1蛋白标记分布,而EGb761+LPS共同诱导THP-1细胞后胞浆中可见少量HMGB1蛋白分布。结论:LPS可诱导THP-1细胞IL-1β、IL-6、TNF-α表达增多及NF-κB活化,导致HMGB1蛋白表达增多及核转位,而EGB761能抑制THP-1细胞IL-1β、IL-6、TNF-α表达及NF-κB活化,调节HMGB1蛋白的表达及核转位。     

坏死细胞释放IL-1β对血管平滑肌细胞侵袭和迁移的影响及机制研究

目的研究坏死血管平滑肌细胞释放IL-1β对周围正常细胞侵袭和迁移的影响,并探讨其可能的机制。方法无血清低糖低氧条件下培养细胞,建立细胞坏死模型,收集坏死细胞培养上清液,用于干预正常血管平滑肌细胞。实验设坏死上清组（NCS）、IL-1β组、NCS＋IL-1RA组和对照组（Control）。Tran-swell小室实验和细胞划痕实验检测各组细胞侵袭和迁徙能力,RT-PCR和Western印迹检测各组MMP-2和MMP-9的表达,Western印迹检测各组NF-κB的激活情况。结果NCS组和IL-1β组细胞侵袭和迁移能力均显著高于对照组（P〈0．05）,NCS＋IL-1RA组细胞侵袭和迁移能力显著低于NCS组和IL-1组（P〈0．05）;对照组和NCS＋IL．1RA组NF-κB、MMP-2和MMP-9均显著低于NCS组和IL-1β组（P〈0．05）,IκB显著高于NCS组和IL-1β组（P〈0．05）。使用NF-κB特异性抑制剂处理后,NCS组和IL-1β组细胞侵袭和迁移能力显著性降低（P〈0．01）;MMP-2和MMP-9的表达也显著性减少（P〈0．01）。结论坏死血管平滑肌细胞能够上调MMP-2和MMP-9的表达,促进正常细胞的侵袭和迁移,且这种促进作用与IL-1β的大量释放诱导NF-κB的活化有关。     

牙龈卟啉单胞菌感染对hPDL细胞中成骨标志基因表达及炎症因子分泌的影响

目的观察牙龈卟啉单胞菌(P.gingivalis)感染对人牙周膜(hPDL)细胞中成骨标志基因表达及炎症因子分泌的影响。方法原代hPDL细胞,分为P.gingivalis感染的P.gingivalis组、常规处理的对照组,成骨诱导后茜素红染色检测矿化结节,PCR法检测成骨标志基因Runt相关转录因子2(RUNX2)、骨钙素(OCN)、骨保护素(OPG)、骨碱性磷酸酶(BALP)的mRNA表达量,ELISA法检测炎症因子肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-1β、IL-6的分泌量,Western blot检测核因子-κB(NF-κB)及NF-κB抑制蛋白(I-κB)的蛋白表达量。结果与对照组比较,P.gingivalis组细胞成骨诱导后茜素红染色的矿化结节明显减少,细胞中RUNX2、OCN、OPG、BALP的mRNA表达量及I-κB的蛋白表达量均明显降低,培养基中TNF-α、IL-1β、IL-6的分泌量及细胞中NF-κB的蛋白表达量均明显增加。结论 P.gingivalis感染hPDL细胞后能够抑制成骨分化、激活炎症反应且该作用与NF-κB通路的激活有关。     

布地奈德对A549细胞胸腺基质淋巴细胞生成素表达作用的研究

目的:观察细胞因子刺激气道上皮细胞胸腺基质淋巴细胞生成素(TSLP)表达是否涉及核因子κB(NF-κB),并探讨糖皮质激素布地奈德对气道上皮细胞TSLP表达和NF-κB核转位的影响.方法:A549细胞与细胞因子白介素1β(IL-1β)、白介素4(IL-4)和布地奈德共同孵育,以不加任何细胞因子或布地奈德培养的A549细胞为对照组,采用RT-PCR方法测定TSLP mRNA表达,细胞免疫荧光方法检测TSLP和NF-κB的表达情况.结果:与对照组比较,IL-1β(10 ng/ml)及IL-4(10 ng/ml)显著刺激A549细胞TSLP mRNA表达,且NF-κB(p65)核转住增加(均P＜0.05).布地奈德干预后TSLP mRNA的表达和NF-κB(p65)的核转位显著减少(P＜0.05).结论:细胞因子促进气道上皮细胞诱导性表达TSLP与NF-κB激活有关,抑制TSLP表达和NF-κB激活可能是布地奈德治疗哮喘的重要机制.     

柚皮苷对骨关节炎软骨破坏的保护作用研究

目的:考察柚皮苷对骨关节炎软骨破坏的保护作用。方法:将60只7周龄雄性SD大鼠随机分为假手术组、模型组和柚皮苷组,每组20只。模型组和柚皮苷组大鼠通过切断右膝关节的前交叉韧带建立骨关节炎模型,建模后,柚皮苷组大鼠每天灌胃200mg/kg的柚皮苷溶液,共灌胃4周。通过番红O/固绿染色和OARSI评分评估大鼠的关节软骨损伤程度。通过免疫组织化学染色检测软骨组织中p-IκBα和NLRP3的表达。通过用IL-1β体外诱导SW1353细胞来模拟骨关节炎软骨细胞的病理微环境,并分别应用NF-κB抑制剂(PDTC)或NLRP3抑制剂(CY-09)处理SW1353细胞。通过RT-PCR和Western blot检测细胞中NF-κB、NLRP3、caspase-1、IL-6、IL-10、IL-18、MMP13和ADAMTS-5的表达。通过Annexin V-FITC/PI法检测细胞凋亡。结果:与模型组相比,柚皮苷组的OARSI评分显著降低(2.63 vs 0.94,P0.05)。柚皮苷组的p-IκBα和NLRP3蛋白表达水平显著低于模型组(P0.05)。与IL-1β组相比,IL-1β+柚皮苷组的SW1353细胞中NF-κB、NLRP3、caspase-1、IL-6、IL-18、MMP13和ADAMTS-5的表达水平均显著降低,而IL-10显著升高(P0.05)。PDTC和CY-09对NF-κB和NLRP3信号通路相关分子的调控作用与柚皮苷一致。与IL-1β组相比,IL-1β+柚皮苷组、IL-1β+PDTC组和IL-1β+CY-09组的细胞凋亡率均显著降低(P0.05)。结论:柚皮苷可在体内和体外抑制骨关节炎的进展,柚皮苷对骨关节炎的治疗作用部分依赖于对NF-κB和NLRP3信号通路的抑制。     

粪肠球菌脂磷壁酸通过 激活NF-κB活化NLRP3炎性体

目的检测粪肠球菌脂磷壁酸(LTA)对NLRP3炎性体的活化机制。方法粪肠球菌LTA及NF-κB抑制剂作用于小鼠巨噬细胞RAW264.7上,运用Western blot及ELISA法检测NLRP3炎性体相关因子mRNA及蛋白的表达,检验LTA对NLRP3的活化是否借助NF-κB信号通路,免疫荧光染色检测NF-κB的核转位。结果LTA可直接活化RAW264.7细胞的NLRP3炎性体。LTA作用于细胞后NLRP3、Caspase-1和IL-1β蛋白的表达明显高于对照组(P0.05)。NF-κB抑制剂可有效抑制NF-κB P65的核转位,而一旦NF-κB信号通路被抑制,NLRP3炎性体蛋白的表达均明显降低。结论 LTA能直接激活小鼠巨噬细胞系RAW264.7的NLRP3炎性体的表达,NF-κB信号通路参与此过程。     

β-淀粉样蛋白对BV2小胶质细胞促炎作用的研究

目的探讨β-淀粉样蛋白(β-amyloid,Aβ)促进BV2小胶质细胞产生炎性因子IL-1β和TNFα的作用机制。方法体外培养BV2小胶质细胞,应用Aβ1-42作用于BV2小胶质细胞,或用吡咯烷二硫代氨基甲酸盐(PDTC)预孵育再给予Aβ1-42刺激,实时荧光定量反转录聚合酶链反应法(RT–PCR)检测IL-1β和TNFαmRNA表达;免疫印迹法(Western blot)检测胞核中NF-κB p65及其抑制蛋白胞浆中IkBα的表达。结果 Aβ1-42作用于BV2小胶质细胞后,Westernblot显示胞浆内IkBα表达下降,胞核内NF-κB p65表达明显增加,RT-PCR测定IL-1β和TNFαmRNA的表达增加;给予NF-κB信号通路特异阻断剂PDTC后,胞浆IkBα的下降和胞核内NF-κB p65的增加均被抑制,同时IL-1β和TNFαmRNA的表达亦受到抑制,PDTC的抑制效果呈剂量依赖性。结论 Aβ可通过激活小胶质细胞NF-κB信号通路促进IL-1β和TNFα的表达。     

人参皂苷Rg1对游离脂肪酸诱导非酒精性脂肪肝细胞炎症的改善作用及机制研究

该研究探讨人参皂苷Rg1对非酒精性脂肪性肝细胞炎症反应的作用及其分子机制。用1 mmol/L游离脂肪酸处理HepG2和L02细胞24 h,再用20μg/mL或40μg/mL人参皂苷Rg1处理6 h;设置对照组、模型组、低剂量Rg1组、高剂量Rg1组。全自动生化仪检测各组细胞上清谷丙转氨酶(alanine aminotransferase,ALT)、谷草转氨酶(aspartate aminotransferase,AST)的含量;酶联免疫吸附法测定细胞上清IL-1β、IL-6、TNF-α。RT-qPCR及Western blot检测NF-κB通路相关基因及蛋白的改变。免疫荧光染色观察NF-κB核转移;Western blot检测各组胞质与胞核内的NF-κB P65蛋白的表达。与对照组相比,模型组培养上清炎症指标明显增加(P<0.05);Rg1能降低炎症指标的表达(P<0.05)。Rg1能减少游离脂肪酸诱导的NF-κB磷酸化及其下游IL-1β、IL-6、TNF-α的表达,减少NF-κB P65从胞质向胞核的转移(P<0.05)。Rg1可通过抑制NF-κB活化减少NASH细胞模型炎症反应,为非酒精性脂肪性肝炎的治疗提供了可能的靶点。     

银杏叶提取物对内毒素诱导巨噬细胞核因子-κB活化及炎性细胞因子表达的调节

探讨银杏叶提取物（EGb761）对内毒素（LPS）诱导RAW264．7细胞核因子-κB（NF-κB）活化及炎性细胞因子基因表达的调节,为银杏叶提取物的临床运用提供理论依据．分别用LPS或EGb761＋LPS处理体外培养的小鼠巨噬细胞系RAW264．7细胞,采用蛋白质印迹分析检测细胞中NF-κB活性,用逆转录-聚合酶链反应（RT-PCR）和酶联免疫吸附法（ELISA）检测细胞中TNF-α、IL-1β、IL-6 mRNA和蛋白的表达．研究结果表明LPS组NF-κB活性和TNF-α、IL-1β、IL-6含量在刺激后2～12h明显高于正常对照组,而EGb761＋LPS组NF-κB活性和TNF-α、IL-1β、IL-6含量均显著低于LPS组．结果提示LPS可诱导RAW264．7细胞NF-κB活化,导致TNF-α、IL-1β、IL-6基因表达增强,而EGb761能抑制NF-κB活化而调节TNF-α、IL-1β、IL-6基因的表达．     

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).