高迁移率族-1 蛋白在烫伤后金葡菌脓毒症中的改变与意义

目的 探讨高迁移率族－1（HMG－1）蛋白在烫伤后金黄色葡萄球菌（简称金葡菌)脓毒症中的变化规律及其调控机制。方法 采用大鼠20％体表面积Ⅲ度烫伤复合金葡菌攻击所致脓毒症模型。70只动物随机分为正常对照组（n=10）、烫伤对照组（n＝10）和烫伤后金葡菌感染组（n＝50）,留取肝、肺组织检测HMG－1及脂多糖结合蛋白（LBP）mRNA表达 ,同时测定组织中金葡菌肠毒素B（SEB）和内毒素含量。结果 烫伤后金葡菌感染可导致动物肝、肺组织HMG－1基因表达明显升高,于伤后6－12h达峰值（P＜0．05－0．01）,至24h仍持续于较高水平。相关分析显示,肝、肺组织LBP基因表达与相应脏器HMG－1mRNA表达呈显著正相关（分别为r＝0．800,P＝0．031和r＝0．942,P＝0．002）,但内毒素与之无明显相关性。结论 烫伤后金葡菌感染可导致动物体内HMG－1基因表达上调,后者作为“晚期炎症介质”可能参与了脓毒症的发病过程。     

生物喋呤合成酶抑制剂在大鼠烫伤后金葡菌脓毒症防治中的意义

目的采用大鼠20%体表面积Ⅲ°烫伤后金黄色葡萄球菌(简称金葡菌)攻击所致脓毒症模型,探讨生物喋呤合成限速酶抑制剂-2,4-二胺-6-羟基嘧啶(DAHP)在金葡菌脓毒症防治中的意义.方法56只动物随机分为正常对照组、烫伤对照组、烫伤后金葡菌感染组和DAHP拮抗组.无菌留取动物心、肝、肺、肾组织,采用RT-RCR方法检测三磷酸鸟苷环水解酶I(GTP-CHI)、诱生型一氧化氮合酶(iNOS)及肿瘤坏死因子-α(TNF-α)基因表达,同时测定上述组织中四氢生物喋呤(BH4)和一氧化氮(NO)的水平.结果烫伤后金葡菌感染可导致组织GTP-CHI基因表达广泛上调、BH4合成显著增加.与之相对应,组织iNOS基因表达和NO水平亦明显升高,其中肝、肺改变尤为显著.给予DAHP不仅可显著抑制各组织GTP-CHI基因表达和BH4的产生,iNOS基因表达和NO的生成亦明显受抑,同时TNF-(基因表达也明显降低.此外,DAHP拮抗组动物6h死亡率明显降低(与未拮抗组相比,P=0.08,趋于统计学意义).结论早期应用DAHP进行干预可在一定程度上改善革兰阳性菌脓毒症动物的预后,其作用机理可能与DAHP抑制了体内BH4和NO的产生有关.     

巨噬细胞移动抑制因子与脓毒症的研究进展

在脓毒症的发病机制中涉及大量炎性细胞因子的失控性释放，巨噬细胞移动抑制因子是脓毒症中一种重要的介质。     

细胞因子信号转导抑制因子3抑制血小板衍生生长因子-BB诱导的血管平滑肌细胞炎症反应的作用及其机制

目的 探讨细胞因子信号转导抑制因子3( SOCS3)抑制血管平滑肌细胞炎症反应的作用及机制.方法 用携带大鼠SOCS3基因的腺病毒(pYrAd-rSOCS3)转染血小板衍生生长因子-BB(PDGF-BB)刺激的大鼠动脉血管平滑肌细胞.实时定量聚合酶链反应(Real time-PCR)检测SOCS3、白细胞介素(IL) -1β、IL-6、肿瘤坏死因子(TNF)-α、单核细胞趋化蛋白-1(MCP-1)及细胞间黏附分子-1(ICAM-1)mRNA表达.Western blot检测SOCS3、信号转导及转录激活因子3(STAT3)、P-STAT3、IL-1β、IL-6、TNF-α、MCP-1及ICAM-1的的蛋白表达.结果 PDGF-BB刺激血管平滑肌细胞24h后,SOCS3、STAT3、P-STAT3、IL-1β、IL-6、TNF-α、MCP-1及ICAM-1表达均上调;pYrAd-rSOCS3转染血管平滑肌细胞后再用PDGF-BB刺激,其SOCS3表达进一步上调,但STAT3、P-STAT3、IL-1β、IL-6、TNF-α、MCP-1及ICAM-1表达明显下调.结论 上调血管平滑肌细胞SOCS3表达通过负反馈调节酪氨酸蛋白激酶(JAK) -STAT3信号通路,抑制STAT3的激活及磷酸化而下调炎性细胞因子表达.     

细胞因子信号转导抑制因子1基因甲基化状态与胃癌幽门螺杆菌感染的关系

目的检测胃癌组织细胞因子信号转导抑制因子（SOCS-1）启动子区甲基化状态,初步探讨其甲基化状态与胃癌幽门螺杆菌（Hp）感染的关系。 方法选取2016年9月至2018年9月接受根治性手术的胃癌患者63例（胃癌组）,另选取同期行胃黏膜病理切片检查的胃黏膜息肉患者67例（对照组）,检测两组胃黏膜组织中SOCS-1基因甲基化状态,实时荧光定量PCR（RT-PCR）法及免疫印迹法检测病理组织SOCS-1 mRNA及蛋白表达水平,快速尿素酶试验检测Hp感染情况,分析胃癌组织SOCS-1甲基化与Hp感染相关性。 结果与对照组相比,胃癌组患者Hp感染阳性率升高（74.60% vs 11.94%,χ²=52.234,P<0.001）,SOCS-1启动子区CpG岛异常甲基化发生率升高（80.95% vs 5.97%,χ²=74.491,P<0.001）。Hp感染阳性胃癌患者的SOCS-1甲基化比例显著增高（95.74% vs 4.26%,χ²=26.261,P<0.001）,Hp感染阳性是SOCS-1甲基化的危险因素（OR=1.576,95% CI：1.126~2.205,P=0.035）。SOCS-1甲基化与胃癌分化程度低、TNM分期、淋巴结转移有关（χ²=11.530、9.380、11.581,均P<0.01）。与Hp感染阴性组相比,Hp感染阳性组SOCS-1 mRNA和蛋白表达量显著降低（P<0.05）。 结论Hp感染可能与SOCS-1 DNA启动子区甲基化密切相关,并通过影响SOCS-1甲基化促进胃癌发生、发展。     

烫伤合并金葡菌感染大鼠组织CD14 mRNA的改变

目的　探讨细菌脂多糖受体CD14在烫伤合并金黄色葡萄球菌 (金葡菌 )感染中的变化规律及其意义。　方法　采用大鼠 2 0 %总体表面积Ⅲ度烫伤合并金葡菌攻击造成脓毒症模型 ,动态检测心、肝、肺、肾等重要器官中CD14mRNA表达的改变 ,同时观察内毒素在动物循环及主要脏器内的分布特点。　结果　烫伤合并金葡菌脓毒症早期 ,各脏器内毒素含量即明显高于正常对照组 ,并于2～ 6h达峰值 ,其中以肝、肺组织内毒素水平升高幅度最为显著 (P <0 .0 5 )。而血浆内毒素水平亦于伤后 2h显著高于正常对照组 (分别为 0 .30 5 6EU/ml和 0 .12 5 0EU/ml,P <0 .0 5 )。与此同时 ,小肠组织中二胺氧化酶的活性明显降低 (P <0 .0 5 )。烫伤合并金葡菌感染后 ,各组织CD14mRNA的表达亦呈不同程度升高 (P <0 .0 5 ) ,其中肺脏改变尤为显著 ,伤后 6、2 4h肺脏CD14mRNA表达分别为正常对照组的 1.80和 1.81倍。　结论　烫伤合并金葡菌攻击可导致内毒素移位和组织CD14mR NA表达不同程度升高 ,CD14基因表达的上调可能与移位内毒素的刺激作用有关。     

生物喋呤合成酶抑制剂对烫伤大鼠金葡菌脓毒症的保护效应及机制

目的　探讨生物喋呤合成限速酶抑制剂 - 2 ,4 二胺 6 羟基嘧啶 (DAHP)对金黄色葡萄球菌 (简称金葡菌 )脓毒症的保护效应及机制。　方法　 5 6只Wistar大鼠随机分为正常对照组、2 0 %TBSAⅢ度烫伤对照组、烫伤后金葡菌感染组和DAHP拮抗组。无菌留取大鼠心、肝、肺、肾组织检测三磷酸鸟苷环水解酶I(GTP CHI)、诱生型一氧化氮合酶 (iNOS)及肿瘤坏死因子α (TNFα )基因表达 ,同时测定组织中四氢生物喋呤 (BH4)和一氧化氮 (NO)的水平。　结果　烫伤后金葡菌感染可导致组织GTP CHI基因表达广泛上调、BH4合成显著增加。同时 ,组织iNOSmRNA表达和NO水平亦明显升高 ,其中肝、肺改变尤为显著。给予DAHP不仅可显著抑制各组织GTP CHImRNA表达和BH4的产生 (P<0 .0 5～ 0 .0 1) ,iNOSmRNA表达和NO的生成亦明显受抑 ,同时TNFα表达也明显降低。此外 ,DAHP拮抗组动物 6h死亡率有所降低 (分别为 2 5 .0 %和 5 5 .6 % ,P =0 .0 8)。　结论　DAHP早期干预可在一定程度上改善革兰阳性菌脓毒症动物的预后 ,其机制可能与DAHP抑制体内BH4和NO的产生有关。     

金黄色葡萄球菌肠毒素B单克隆抗体对烫伤脓毒症大鼠急性肺损伤的影响

目的探讨金黄色葡萄球菌(简称金葡菌)肠毒素B(SEB)单克隆抗体(单抗)对烫伤脓毒症大鼠急性肺损伤的保护作用。方法雄性Wistar大鼠56只随机分为正常对照组(n=10)、烫伤对照组(n=10)、烫伤后金葡菌感染组(n=20)和SEB单克隆抗体(单抗)拮抗组(n=16)。测定肺组织SEB水平、髓过氧化物酶(MPO)活性、肿瘤坏死因子(TNF)-α和干扰素(IFN)-γ表达的改变。结果烫伤后金葡菌脓毒症动物肺脏SEB含量明显升高,伤后2、6h分别为66.85ng/g组织和92.46ng/g组织,与正常对照组(14.26ng/g组织)和烫伤对照组(17.32ng/g组织)相比均为P＜0.01;同时,肺组织MPO活性显著增强,峰值可达7.39U/g组织,与正常对照组(2.09U/g组织)相比P＜0.05。与之相应,肺组织MPO活性显著增强(P<0.05)。同时,局部组织IFN-γ和TNF-α基因及其蛋白质表达明显上调(P<0.05),并与肺脏SEB含量呈高度正相关(分别为r=0.9207、P=0.0033和r=0.8142、P=0.0258)。SEB单抗早期干预可有效降低肺组织中SEB含量,并显著抑制IFN-γ和TNF-α的产生,肺脏病理改变亦明显减轻。结论SEB单抗干预可抑制IFN-γ和TNF-α等炎症介质的产生,从而显著减轻烫伤后金葡菌对机体的损害。     

巨噬细胞移动抑制因子与脓毒症的研究进展(文献综述)

在脓毒症的发病机制中涉及大量炎性细胞因子的失控性释放 ,巨噬细胞移动抑制因子是脓毒症中一种重要的介质。     

烫伤大鼠创面脓毒症发生后肝组织中脂代谢相关基因表达水平的变化

目的检测烫伤大鼠创面脓毒症发生后肝脏组织中脂代谢相关基因表达水平的变化，并分析其意义。方法将60只背部30％TBSAⅢ度烫伤大鼠随机分为创面脓毒症组和对照组，每组30只。创面脓毒症组大鼠创面涂布铜绿假单胞菌菌液，并对相应指标进行检测以确定该组大鼠是否符合创面脓毒症诊断标准。对照组除创面不涂菌液外，其余操作及检测同创面脓毒症组。两组大鼠于伤后96h断颈处死，通过基因芯片杂交方法检测两组肝组织中表达水平有显著差异的基因，并按其功能筛选出与脂代谢相关的基因。结果两组大鼠肝组织中共检出47种表达水平差异较显著的基因，其中9种基因与脂代谢相关。创面脓毒症组大鼠这9种基因中表达上调的是与脂肪酸转运和活化功能相关的多种酶基因，表达下调的是与脂肪酸在线粒体内氧化供能相关的多种酶基因。结论烫伤大鼠创面脓毒症的发生引起肝脏组织中多种脂代谢相关基因表达水平改变，加重了烫伤后的脂代谢紊乱；初步判断脂代谢障碍的发生部位为线粒体。     

Significance of biopterin induction in rats with postburn Staphylococcus aureus sepsis

Objective: It has been demonstrated that biopterin, an essential cofactor of nitric oxide synthase (NOS), plays an important role in the pathogenesis of endotoxin-induced shock, yet its biological significance in gram-positive sepsis remains unclear. In this study, we adopted a rat model of postburn Staphylococcus aureus (S.aureus) sepsis to observe the time course and tissue distribution of biopterin in postburn S. aureus infection, and to investigate its potential role in the pathogenesis of gram-positive sepsis. Wistar rats were inflicted with a 20% total body surface area (TBSA) full-chickness scald injury followed by S. aureus challenge, then guanosine triphosphatecyclohydrolase I (GTP-CHI) mRNA expression and biopterin levels in liver, kidneys, lungs and heart were determined at 0. 5, 2, 6, 12 and 24 hours after S. aureus challenge. We found that after S. aureus challenge, GTP-CHI gene expressions and biopterin levels were markedly up-regulated in various tissues, and remained at high values up to 24 hours (P＜ 0. 05-0.01). Meanwhile, the organ function indexes, including serum alanine amimotransferase (ALT), aspartate aminotransferase (AST), creatinine (Cr), MB isoenzyme of creatine kinase (CK-MB), levels and pulmonary myeloperoxidase (MPO) activities significantly increased at 24 hours postburn, and the multiple organ dysfunction was aggravated by S. aureus challenge. Moreover, it was shown that cardiac GTP-CHI mRNA expression and renal BH4levels were positively correlated with CK-MB and Cr (r=0. 892, P=0. 0012 and r=0. 9423,P=0.0015, respectively). Conclusion: These results suggested that thermal injury combined with S. aureus challenge could induce de novo biosynthesis of biopterin, which acts as the most important cofactor of iNOS, might play a role in the development of multiple organ dysfunction syndrome secondary to postburn sepsis.     

The effect of 2,4-diamino-6-hydroxy-pyrimidine on postburn Staphylococcus aureus sepsis in rats

GTP-cyclohydrolase I (GTP-CHI) is the first and rate-limiting enzyme for the de novo biosynthesis of biopterin. The present study was to observe the effect of 2,4-diamino-6-hydroxy-pyrimidine (DAHP),an inhibtor of GTP-CHI, on the development of postburn Staphylococcus aureus sepsis. Methods: 56 male Wistar rats were randomly divided into four groups as follows: normal control group (n= 10), scald control group(n= 10),pos tburn sepsis group (n= 20) and DA HP treatment group (n= 16). In the scald control group, rats were subjected to a 20% total body surface area (TBSA) Ⅲ° scald injury, then sacrificed at 24 hrs. In the postburn sepsis group (n=20), rats were inflicted with 20% TBSA Ⅲ° scald followed by Staphylococcus aureus challenge, and they were further divided into 2 and 6 hrs groups. In the DAHP treatment group (n= 16), animals were intraperitoneally injected with a dose of 1g/kg DAHP prior to Staphylococcus aureus challenge, and then further divided into 2, 6 hrs groups. Tissue samples from liver, kidneys, lungs and heart were collected to determine GTP-CHI, inducible nitric oxide synthase (iNOS) and tumor necrosis factor-α (TNF-α) mRNA expression. Meanwhile, biopterin and nitric oxide (NO) levels in these tissues were also measured. Results: After the scald injury followed by Staphylococcus aureus challenge, GTP-CHI mRNA expression and biopterin levels significantly elevated in various tissues such as liver, heart, kidneys and lungs, so did the values of iNOS mRNA expression and NO formation (P＜0.01). Pretreatment with DAHP could significantly reduce GTP-CHI/biopterin induction (P＜0. 05～0. 01), and the up-regulation of iNOS/NO was also suppressed. Furthermore, DAHP administration could also inhibit the gene expression of TNF-α. 2 hrs after septic challenge, TNF-α mRNA expression in liver, kidneys and lungs in DAHP-treated group were 35.7%, 37.3% and 33.0% of those in postburn septic group, respectively. Additionally, in animals without DAHP treatment, the 6-hour mortality was 55.6% (20/36), while it was only 25.0% in DAHP-treated animals (4/16, P=0. 08). Conclusions: Early treatment with DAHP might be a potential strategy to prevent the development of postburn Staphylococcal sepsis, which appears to be associated with down-regulation of biopterin and NO formation by DAHP.     

细胞外信号调节激酶抑制剂对烫伤脓毒症大鼠肿瘤坏死因子-α表达的影响及意义

目的　观察细胞外信号调节激酶 (ERK)抑制剂对烧伤后金黄色葡萄球菌 (金葡菌 )脓毒症动物组织肿瘤坏死因子 (TNF) α表达及多器官功能损害的影响。方法　采用SD大鼠 2 0 %总体表面积Ⅲ度烫伤后金葡菌攻击所致脓毒症模型 ,34只动物随机分为正常对照组 (n =6 )、烫伤对照组 (n=6 )、烫伤后金葡菌感染组 (n =12 )和ERK抑制剂AG12 6拮抗组 (n =10 ) ,检测动物肝、肾、肺组织中ERK磷酸化和TNF α基因 /蛋白表达的改变。结果　烫伤脓毒症后 0 5～ 2 0h肝、肺、肾组织ERK均呈现不同程度的活化 ,其中 2 0h分别为正常对照组的 1 94倍 (P <0 0 5 )、2 86倍 (P <0 0 1)、1 4 1倍。AG12 6拮抗组肺组织磷酸化ERK水平在 2 0h下降 70 6 % (P <0 0 1) ,而肝、肾组织其磷酸化水平不同时相点几乎完全抑制 ,同时各组织中TNF α基因及蛋白表达水平明显下调 (P<0 0 5或 0 0 1)。与烫伤脓毒症组相比 ,AG12 6拮抗组 2 0h肝、肾功能指标明显改善 ,肺组织髓过氧化物酶活性下降 4 0 3% (P <0 0 5 )。结论　ERK信号通路参与了严重烧伤后金葡菌感染所致炎症反应与急性组织损伤的病理过程 ,针对该环节进行早期干预可有效缓解多器官功能异常改变。     

The clinical significance of Staphylococcus aureus bacteriuria

To investigate the rate of occurrence, clinical presentation, predisposing factors and frequency of secondary bacteremia 132 patients with significant Staphylococcus aureus bacteriuria were reviewed retrospectively. Staphylococcus aureus accounted for 3.3 per cent of all positive urine cultures. Most patients were elderly men. The most important predisposing factors in the urinary tract were indwelling catheters (63 per cent), obstruction (56 per cent) and instrumentation or surgery (43 per cent). Bacteremia developed secondary to bacteriuria in all 11 patients (8.3 per cent). For that reason Staphylococcus aureus bacteriuria should be regarded as a hazardous condition, especially in patients with predisposing factors in the urinary tract.     

调节性T淋巴细胞与严重烧伤脓毒症

许多资料显示,大面积烧伤并发的脓毒症来势凶猛,病情进展迅速,患者病死率高,给临床救治工作带来极大困难.及时诊断、有效预防和治疗烧伤脓毒症,是提高严重烧伤救治成功率的关键.随着对感染病理生理过程认识的不断深化,人们对烧伤后脓毒症的发病机制有了新的了解.