结核分枝杆菌优势蛋白ppe37的表达纯化以及对巨噬细胞NF-κB、TNF-α、IL-6m RNA表达的影响

目的 研究在结核分枝杆菌感染过程中,ppe37蛋白引起的巨噬细胞免疫应答反应.方法 利用本实验室已构建好的ppe37原核表达载体,将其转化到大肠杆菌E.col BL21中,用IPTG诱导表达后,经SDS-PAGE与Western blot鉴定后,利用Ni-Agarose His标签蛋白纯化试剂金对重组蛋白进行纯化并复性.利用SDS-PAGE和AlpHaImager 2200软件对纯化蛋白进行鉴定与分析.分别用浓度为100 ng/ mL、500 ng/mL、5 000 ng/mL的重组ppe37蛋白刺激RAW264.7巨噬细胞,24 h、48 h、72 h后,用Real-time PCR检测RAW264.7巨噬细胞NFκB、TNF-α、IL-6 mRNA的表达量的变化.结果 SDSPAGE鉴定显示,重组ppe37蛋白获得了大量表达,其相对分子质量约为50 kDa.经Western Blot验证,重组ppe37蛋白可与抗His单抗发生特异性反应,经AlpHaImager 2200软件薄层扫描分析,重组蛋白的纯度为96.2％,并成功的进行了蛋白复性.浓度分别为100 ng/ mL,500 ng/ mL,5 000 ng/ mL的重组ppe37蛋白刺激巨噬细胞,24 h后Real-Time PCR检测结果显示与空白对照组相比NF-κB、TNF α mRNA的表达没有影响(P＞0.05),而IL-6 mRNA的表达上调(P＜0.05);48 h、72 h后NF κB、TNF-α 、IL-6 mRNA的表达显著上调(P＜0.05).结论 成功地制备并纯化了重组ppe37蛋白,重组ppe37蛋白能够活化巨噬细胞,激活细胞免疫反应,并促使巨噬细胞发生炎性反应.     

RAW264.7细胞M1/M2亚型的诱导和鉴定

目的诱导小鼠巨噬细胞RAW264.7分化为M1/M2亚型,并分别根据其标志物的表达情况进行鉴定。方法干预前一天以105个/ml密度铺好细胞,用不同浓度的IFN-γ+LPS干预,刺激分化为M1亚型;用不同浓度IL-4干预,刺激分化为M2亚型。分别于干预后12h提取细胞的总RNA。用realtime PCR方法对M1/M2亚型的标志物iNOS,CD86/MR(CD206),I型精氨酸酶(ArginaseI,Arg-I)进行mRNA水平表达量的鉴定,最终选择最合适的刺激浓度进行后续试验。结果 (1).不同浓度干预试剂刺激12h后,大剂量干预组RAW264.7的细胞状态差,死亡细胞数多,中小剂量组细胞状态良好,完全贴壁,但细胞的形态发生改变;(2).2.5ng/ml IFN-γ+200ng/ml LPS共同作用12h后,RAW264.7的iNOS和CD86表达量最高,较基础水平有明显差异;(3).10ng/ml IL-4作用12h后,RAW264.7的MR(CD206)和ArgI的表达量最高,较基础水平有明显差异。结论用适当浓度的IFN-γ+LPS/IL-4刺激RAW264.7细胞12h,可使其分化为M1/M2亚型。     

库普弗细胞内毒素耐受时白细胞介素-1受体相关激酶-4的表达变化

目的观察库普弗细胞（KCs）内毒素耐受形成后白细胞介素-1受体相关激酶4（IRAK-4）表达的变化，探讨KCs内毒素耐受形成的相关机制。方法分离培养Balb／c小鼠KCs，分为非内毒素耐受组与内毒素耐受组[给予脂多糖（LPS）10ng／ml预处理24h]。用LPS100ng／ml刺激后，蛋白免疫印迹法及逆转录聚合酶链反应法测定两组细胞IRAK-4蛋白及mRNA的表达水平；酶联免疫吸附法检测两组细胞核因子-κB（NF-κB）活性及培养上清液肿瘤坏死因子α（TNFα）含量。结果LPS刺激在两组细胞均引起IRAK-4 mRNA表达及NF-κB活性增强、TNFα释放增加，但内毒素耐受组3种指标的高峰值明显低于非内毒素耐受组（t值分别为l2．4、l7．4、l38．9，P值均〈0．01）。结论LPS预处理可诱导KCs形成内毒素耐受状态，IRAK4表达受到抑制可能是KCs内毒素耐受形成的机制之一。     

各种脂质对肾小管上皮细胞人尿酸盐转运子基因表达的影响

目的 观察不同浓度脂蛋白和游离脂肪酸对肾小管上皮细胞(HK-2细胞)人尿酸盐转运子(hUAT)mRNA表达的影响.方法 0、50、100、200、400μg/ml低密度脂蛋白(LDL)、极低密度脂蛋白(VLDL)、高密度脂蛋白(HDL)和0、100、200、400 p,mol/L软脂酸、油酸孵育HK-2细胞48 h,采用实时PCR检测hUAT mRNA的相对表达量.结果 干预48 h后,随LDL、VLDL、HDL浓度的增加,hUAT mRNA表达水平均显著下降(LDL:1.00,0.44,0.26,0.20,0.10;VLDL:1.00,0.64,0.48,0.30,0.24;HDL:1.00,0.44,0.34,0.15,0.13:均P<0.01).不同浓度软脂酸、油酸对hUAT的表达均无显著影响(均P>0.05).结论 脂蛋白中的甘油三酯和胆固醇可降低肾小管上皮细胞的hUAT mRNA表达,可能是脂代谢紊乱引起高尿酸血症的重要机制.     

IL-10对急性坏死性胰腺炎大鼠NF—κB及IL-12水平的影响

目的观察白介素10（IL-10）对ANP大鼠NF—κB和IL-12表达的影响，探讨IL-10的作用机制。方法将92只SD大鼠按随机分组法分为对照组、ANP组和IL-10干预组。采用3次腹腔注射左旋精氨酸（1．0mg／g体重）的方法制备ANP模型。对照组腹腔注射等量生理盐水。IL-10组在制模后2、5、8h分别于腹腔内注射IL-10 10 000U。制模后4、12、24、36h分批处死动物，观察血清淀粉酶、IL-12及胰腺组织NF—κB水平的变化。结果制模后24h点IL-10组胰腺病理分值为4．75±1．75，胰腺NF—κB含量为（112．89±34．48）μg/ml，血清淀粉酶含量为（1481．13±336．48）U／L，血清IL-12水平为（81．31±17．23）pg／ml，均明显低于同时点ANP组大鼠（P〈0．05或P〈0．01）。NF—κB和IL-12呈正相关（r=0．494，P〈0．01），两者与胰腺病理分值也呈正相关（r=0．447和r=0．603，P〈0．01）。结论IL-10对ANP有一定的治疗作用，其机能可能通过抑制NF—κB途径而抑制ANP的炎症反应。     

细粒棘球蚴抗原B对小鼠巨噬细胞RAW264.7的极化作用

目的探讨细粒棘球蚴抗原B (AgB)对巨噬细胞极化的调控作用。方法将RAW264.7巨噬细胞培养24 h后，分为M1、 M2、 AgB、 AgB+M1、 AgB+M2和空白对照组（M0组），每组3孔。待所有巨噬细胞贴壁3 h后，AgB、 AgB+M1、 AgB+M2组均加入羊源细粒棘球蚴囊液提取的天然AgB （终浓度为1 000 ng/ml），刺激1 h后，M1组和AgB+M1组加入脂多糖（LPS，终浓度为100 ng/ml）和γ干扰素（IFN-γ，终浓度为20 ng/ml）刺激分化20 h;M2组和AgB+M2组加入白细胞介素4 (IL-4)、IL-13 （终浓度均为20 ng/ml）刺激分化20 h；空白对照组不更换培养液，同步培养20 h。显微镜下观察巨噬细胞形态。提取各组巨噬细胞总RNA, RT-PCR检测刺激后巨噬细胞表面标志物精氨酸酶1 (Arg-1)、肿瘤坏死因子α (TNF-α)的mRNA相对转录水平；蛋白质免疫印迹（Western blotting）分析巨噬细胞蛋白Arg-1、诱导型一氧化氮合酶（iNOS）的相对表达量；ELISA检测刺激后巨噬细胞培养上清中IL-10...     

EPO对大鼠脑出血血肿周围组织细胞凋亡与NF—κB表达的影响

目的研究脑出血后血肿周围组织细胞凋亡与核转录因子κB（NF—κB）的表达及促红细胞生成素（EPO）的干预作用。方法将126只大鼠随机分为假手术组、脑出血组、EPO干预组,每组各42只,建立脑出血模型。EPO干预组大鼠于造模后及每24h腹腔注射人重组促红细胞生成素（rhEPO）3000U／kg。分别在术后3h、6h、12h、24h、48h、72h、7d断头取脑,作NF-κB免疫组化染色和原位末端标记（TUNEL）染色,观察各组各时间点NF—κB的表达及TUNEL阳性细胞数。结果与脑出血组比较EPO干预组NF-κB表达增多,凋亡细胞减少。结论脑出血周围细胞凋亡与NF—κB表达均有增多,EPO通过促进NF—κB活化抑制细胞凋亡,从而起到神经保护作用。     

果蝇样受体4介导游离脂肪酸调节人血管平滑肌细胞单核细胞趋化蛋白-1的表达

目的探讨软脂酸对人主动脉血管平滑肌细胞（HA—VSMC）单核细胞趋化蛋白-1（MCP-1）基因表达的调节及果蝇样受体4（TLR4）信号通路的作用。方法采用不同剂量的软脂酸（100、200、400μmol/L）处理HA—VSMC6、12、24h,采用实时荧光定量聚合酶链反应（PCR）检测细胞MCP．1mRNA表达,酶联免疫吸附实验（ELISA）检测MCP-1蛋白表达,观察软脂酸调节MCP-1表达的剂量依赖关系和时间效应;采用蛋白激酶C（PKC）抑制剂白屈菜红碱、磷脂酰肌醇3激酶（P13K）抑制剂wortmannin、神经酰胺抑制剂myriocin和核因子KB（NF—KB）抑制剂parthenolide分别处理细胞30min,再加入软脂酸（400μmol/L）处理细胞6h后,实时荧光定量PCR检测MCP-1mRNA的表达水平,ELISA检测MCP-1的蛋白表达水平,研究软脂酸调节MCP-1表达依赖的信号通路;构建TLR4短发夹RNA（shRNA）腺病毒pGSadeno-TLR4并感染HA—VSMC沉默TLR4基因表达,实验同时设空白对照组（PBS缓冲液）和对照病毒（pGSadeno-GFP）组。细胞感染96h后更换培养基,再加入软脂酸（400μmoL／L）处理细胞6h,采用实时荧光定量PCR检测MCP-1mRNA表达水平,ELISA检测MCP-1的蛋白表达水平。提取细胞核蛋白,采用ELISA检测NF—KBp65亚基活性,观察TLR4／NF-KB通路在软脂酸调节HA-VSMCMCP-1基因表达中的作用。组间均数比较采用单因素方差分析。结果采用软脂酸处理细胞6h后,对照组及100、200和400μmoVL软脂酸组MCP-1mRNA表达分别为1．00±0．02、3．30±2．84、8．21±4．31和11．25±2．73（F=7．57,P〈0．05）;MCP-1蛋白表达分别为（127±10）、（147±10）、（163±18）和（194±14）ng／L（F=7．81,P〈0．05）。软脂酸可促进HA-VSMCMCP-1mRNA和蛋白表达且具有明显的剂量依赖关系。细胞培养12h和24h后,随着软脂酸浓度的增加,MCP-1mRNA和蛋白表达水平呈逐渐增加趋势,但时间效应则不明显。采用不同的信号通路抑制剂和软脂酸处理细胞6h后,对照组、软脂酸组、软脂酸＋parthenolide组、软脂酸＋白屈菜红碱组、软脂酸＋wortmannin组和软脂酸＋myriocin组MCP-1mRNA表达分别为1．00±0．02、10．80±1．23、3．49±0．28、10．84±0．24、11．24±0．27和10．62±0．36（F=1313．07,P〈0．05）;MCP-1蛋白表达分别为（132±8）、（218±12）、（152±4）、（213±12）、（225±7）和（226±9）ng／L（F=106．83,P〈0．05）。成功地构建并获得TLR4shRNA腺病毒pGSadeno—TLR4,采用pGSadeno-TLR4感染HA—VSMC阻断TLR4信号后,软脂酸＋pGSadeno．TLR4组的NF—KB065结合活性、MCP-1mRNA和蛋白表达均显著低于软脂酸组[分别为0．48±0．12比1．24±0．16、1．88±0．33比10．80±1．23、（154±10）比（218±12）ng／L;F=591．86、659．16、118．37,均P〈0．01]。而对照病毒pGSadeno．GFP对软脂酸诱导的NF—KB065结合活性和MCP：I表达均无明显影响。结论TLR4／NF—KB信号通路介导了软脂酸诱导的人主动脉血管平滑肌细胞MCP-1基因表达。     

LOX-1/NF-κB信号途径对ox-LDL刺激的人脐静脉内皮细胞炎症因子表达的影响及氟伐他汀的干预作用

目的：探讨血凝素样氧化型低密度脂蛋白受体-1（LOX-1）/核因子（NF）-κB信号途径对氧化低密度脂蛋白（ox-LDL）刺激的人脐静脉内皮细胞（HUVECs）炎症因子表达的影响及氟伐他汀的干预作用。方法：设立不同浓度的ox-LDL刺激组,LOX-1中和抗体干预组,NF-κB抑制剂吡咯烷二硫代氢基甲酸盐（PDTC）干预组,氟伐他汀干预组及空白对照组;检测细胞上清液中肿瘤坏死因子（TNF）-α,白细胞介素（IL）-6的浓度。结果：25mg/L、50mg/L、100mg/L浓度的ox-LDL刺激组24h后上清液TNF-α浓度分别为：（32.34±2.46）pg/ml、（96.43±8.36）pg/ml、（62.79±4.64）pg/ml,IL-6浓度分别为：（264.71±15.06）pg/ml、（630.70±17.77）pg/ml、（378.62±16.33）pg/ml,均较空白对照组TNF-а（22.99±3.55）pg/ml、IL-6（80.37±8.29）pg/ml水平显著升高（P〈0.05~0.01）;NF-кB抑制剂PDTC和LOX-1中和抗体干预后上清液TNF-α浓度较50mg/L ox-LDL刺激组显著下降（P〈0.01）。不同浓度氟伐他汀（0.01μmol/L、0.1μmol/L、1μmol/L）干预HUVECs 24h后上清液TNF-α浓度分别为（73.84±6.50）pg/ml、（42.59±6.45）pg/ml、（23.55±4.27）pg/ml;IL-6浓度分别为（549.0±20.23）pg/ml、（434.56±22.4）pg/ml、（302.42±21.30）pg/ml,较50mg/L ox-LDL刺激组显著下降（P〈0.05~0.01）。结论：氧化低密度脂蛋白可刺激人脐静脉内皮细胞上清液中炎症因子TNF-α和IL-6的表达,在25~50mg/L剂量范围内呈显著的剂量-效应关系。氟伐他汀可浓度依赖性抑制人脐静脉内皮细胞上清液中炎症因子TNF-α和IL-6的表达。     

血管紧张素Ⅱ对培养血管内皮细胞核因子-κB激活及厄贝沙坦干预研究

目的观察血管紧张素Ⅱ(AngⅡ)刺激人脐静脉血管内皮细胞(HUVEC)核因子-κB(NF-κB)激活与其对肿瘤坏死因子-α(TNFα)、白介素-6(IL-6)表达的影响及血管紧张素1型受体(AT1R)拮抗剂厄贝沙坦(irbesartan，Irb)干预后的变化，以探讨AngⅡ／NF-κB在动脉粥样硬化(AS)致病机制中的作用和Irb可能的抗AS效应。方法体外培养HLIVEC，测定AngⅡ刺激下NF-κB亚单位p65的核易位阳性率、TNFα、IL-6的时间与浓度反应曲线；然后将分盘于24孔板的细胞随机分为5组(n=6)：正常培养对照组、AngⅡ刺激组，AngⅡ和3种不同浓度的Irb共孵育组；采用细胞ELISA、免疫细胞化学分析分别测定TNFα、IL-6的含量和NF-κBp65的核易位阳性率。结果AngⅡ(1nmol／L-5μmol／L)刺激HUVEC表达TNFα、IL-6呈时间与浓度依赖性，其表达高峰分别为12～24h、6～12h，NF-κBp65核易位阳性率亦呈时间浓度依赖性，高峰在1～4h。厄贝沙坦(0．01μmol／L、0．1μmol／L、1μmol／L)均能显降低TNFα和IL-6表达与NF-κBp65核易位阳性率。结论AngⅡ以浓度和时间依赖方式刺激HUVEC NF-κB激活与TNFα、IL-6表达，厄贝沙坦抑制HUVEC NF-κB激活与TNFκ、IL-6表达，提示AngⅡ／NF-κB信号途径在促进AS发病机制中起重要作用，拮抗AT1R或抑制NF-κB有可能减轻或抑制AS进展。     

软脂酸和花生四烯酸对人肝细胞瘤细胞株细胞葡萄糖摄取的影响

脂肪酸对人肝细胞瘤细胞株(HepG2)细胞葡萄糖摄取研究显示，高浓度的软脂酸可通过抑制HepG2细胞胰岛素受体和葡萄糖转运子2的表达抑制胰岛素刺激的葡萄糖摄取；花生四烯酸可通过类似机制刺激葡萄糖摄取，部分阻断软脂酸的作用。     

Plasma-free eicosapentaenoic acid/arachidonic acid ratio: a possible new coronary risk factor

Seventy-six effort angina patients who had typical angina on exertion documented by treadmill stress test with evidence of ischemic ST-segment depression and 78 healthy volunteers in urban Japan were investigated in this study. Plasma free fatty acids (FFA) in both groups were determined using high-performance liquid chromatography. The relationships between the total cholesterol, high-density lipoprotein (HDL), triglycerides in plasma, and the genesis of coronary heart disease were also examined. The ratio (0.08 +/- 0.08) of eicosapentaenoic acid (EPA)/arachidonic acid (AA) in plasma FFA was significantly lower in effort angina patients than that (0.15 +/- 0.12) in healthy volunteers. The lower ratio was due to significantly lower levels of EPA in the patients than in normals. In 42% of angina patients, the ratio is below 0.03. In all age subgroups except the age 30-39 subgroup, the ratio of EPA/AA was significantly lower in patients than in normals, when divided into four subgroups by using a 10-year age interval. Though the total cholesterol and triglycerides were not significantly different between the two groups, HDL was significantly lower and total cholesterol/HDL ratio was significantly higher in effort angina patients than in healthy volunteers. However, there was no correlation between EPA/AA ratio and HDL in individuals in either group. From these results, it could be concluded that lower EPA/AA ratio is a new coronary risk indicator other than HDL.     

Innovations in host and microbial sialic acid biosynthesis revealed by phylogenomic prediction of nonulosonic acid structure

Sialic acids (Sias) are nonulosonic acid (NulO) sugars prominently displayed on vertebrate cells and occasionally mimicked by bacterial pathogens using homologous biosynthetic pathways. It has been suggested that Sias were an animal innovation and later emerged in pathogens by convergent evolution or horizontal gene transfer. To better illuminate the evolutionary processes underlying the phenomenon of Sia molecular mimicry, we performed phylogenomic analyses of biosynthetic pathways for Sias and related higher sugars derived from 5,7-diamino-3,5,7,9-tetradeoxynon-2-ulosonic acids. Examination of ≈1,000 sequenced microbial genomes indicated that such biosynthetic pathways are far more widely distributed than previously realized. Phylogenetic analysis, validated by targeted biochemistry, was used to predict NulO types (i.e., neuraminic, legionaminic, or pseudaminic acids) expressed by various organisms. This approach uncovered previously unreported occurrences of Sia pathways in pathogenic and symbiotic bacteria and identified at least one instance in which a human archaeal symbiont tentatively reported to express Sias in fact expressed the related pseudaminic acid structure. Evaluation of targeted phylogenies and protein domain organization revealed that the “unique” Sia biosynthetic pathway of animals was instead a much more ancient innovation. Pathway phylogenies suggest that bacterial pathogens may have acquired Sia expression via adaptation of pathways for legionaminic acid biosynthesis, one of at least 3 evolutionary paths for de novo Sia synthesis. Together, these data indicate that some of the long-standing paradigms in Sia biology should be reconsidered in a wider evolutionary context of the extended family of NulO sugars.     

Perinatal bile acid metabolism: bile acid analysis of meconium of preterm and full-term infants

Background Our purpose was to evaluate the metabolism of bile acids in the fetus by analyzing the bile acid composition of meconium of preterm (less than 30 weeks’ gestational age) and full-term infants and comparing the results with the bile acid composition of feces of preterm and full-term infants 6 days after delivery. Methods The concentrations of individual bile acids were determined by gas chromatography-mass spectrometry after solvolysis and hydrolysis of bile acid conjugates. Results In meconium, the main bile acids were chenodeoxycholic and hyocholic acids. The main bile acid of feces from preterm infants at 6 days of age was the same as that of meconium. We also detected large amounts of secondary bile acids, especially deoxycholic acid and ursodeoxycholic acid. The ratio of cholic acid relative to chenodeoxycholic acid in meconium of preterm and full-term infants and in feces of preterm infants was less than 1, 0.36, 0.55, and 0.55, respectively. The percentage of chenodeoxycholic acid relative to total bile acids in meconium of preterm (P < 0.05) and full-term (P < 0.01) infants was significantly higher than that in feces of 6-day-old full-term infants. Conclusions More than half of the main pathway, at least, for bile acid synthesis in preterm infants may be the acidic pathway until the infants reach about 7 days of age.     

妥塞敏治疗肺结核咯血的效果观察

目的　比较妥塞敏和止血芳酸治疗肺结核咯血的效果和不良反应。方法 于2002—2003年采用前瞻性、随机抽样和多中心研究方法,选入并分析轻度和中度咯血患者118例,其中采用妥塞敏60例、止血芳酸58例。2组性别、年龄、病变、咯血严重程度和咯血史以及合并支气管扩张均相似。结果 妥塞敏组和止血芳酸组3日咯血治愈率分别为55%和41.4%(P＞0.05);7日治愈率分别为95%和81%(P＜0.01)。妥塞敏和止血芳酸对初治咯血疗效要优于多次咯血者,无明显不良反应。结论 3日妥塞敏效果与止血芳酸相似,而7日妥塞敏则优于止血芳酸。     

Basal acid output and gastric acid hypersecretion in gastroesophageal reflux disease

The purpose of this study was to evaluate possible differences in basal gastric acid secretion with regard to severity of gastroesophageal reflux disease. Basal acid output was determined by nasogastric suction in 228 patients with gastroesophageal reflux disease who received upper gastrointestinal endoscopy and were diagnosed with either pyrosis alone (N = 98), erosive esophagitis with or without pyrosis (N = 87), or Barrett's esophagus (N = 43). Mean basal acid output for the 228 patients with gastroesophageal reflux disease was 6.5 ± 5.6 meq/hr, which was significantly different from 65 normal subjects with a mean basal acid output of 3.0 ± 2.7 meq/hr (P < 0.0001). Compared to normal subjects, mean basal acid outputs significantly differed for patients with pyrosis (P < 0.05), esophagitis (P < 0.01), and Barrett's esophagus (P < 0.01). There was also a significant difference in mean basal acid output between the patients with pyrosis and Barrett's esophagus (P < 0.01). Nineteen of the 98 patients with pyrosis (19%), 24 of the 87 patients with esophagitis (28%), and 15 of the 43 patients with Barrett's esophagus (35%) had gastric acid hypersecretion (basal acid output greater than 10.0 meq/hr). One hundred forty-six patients with gastroesophageal reflux disease were treated with ranitidine in doses that resulted in complete healing of esophagitis and disappearance of pyrosis. Ninety-three patients responded to ranitidine 300 mg/day; however, 53 patients required increased dose of ranitidine (mean 1205 mg/day, range 600–3000 mg/day). There was a significant correlation between basal acid output and daily ranitidine dose required for therapy for the 146 patients with gastroesophageal reflux disease (r = 0.53,P = 0.0001). Furthermore, a significant association was also found between the presence of gastric acid hypersecretion and the requirement for increased doses of ranitidine (greater than 300 mg/day) (P = 0.00001). These results indicate that there is a subset of patients with gastroesophageal reflux disease who do have idiopathic gastric acid hypersecretion. Moreover, these patients have an apparently higher requirement for medication dosage in order to achieve therapeutic efficacy.