p38丝裂原活化蛋白激酶信号通路特异性阻滞药对癫痫模型大鼠神经细胞的保护作用研究

目的:研究p38丝裂原活化蛋白激酶信号通路特异性阻滞药SB203580对癫痫模型大鼠神经细胞的保护作用。方法:取大鼠随机分为正常对照组、模型组和SB203580低、中、高剂量(5、10、20mg.kg-1)组,每组10只,后4组腹腔注射戊四唑建立癫痫模型,SB203580各剂量组建模前10min腹腔注射相应药物。建模给药后按Racine分级标准对各组大鼠进行行为学评价,建模给药后2h检测各组脑组织中乳酸脱氢酶(LDH)释放率,采用免疫组化法和免疫印迹法检测海马组织中半胱氨酸天冬氨酸蛋白酶3(Caspase-3)的表达。结果:正常对照组无癫痫发作;与正常对照组比较,模型组癫痫发作程度明显增强,LDH释放率明显升高,Caspase-3阳性细胞数及其表达明显增加(P<0.01);与模型组比较,SB203580各剂量组癫痫发作程度明显减轻,LDH释放率明显降低,Caspase-3阳性细胞数及其表达明显减少(P<0.05或P<0.01),且与剂量成正相关。结论:SB203580可能通过间接抑制Cas-pase-3表达实现对癫痫模型大鼠神经细胞的保护作用。     

Recombinant YopJ induces apoptotic cell death in macrophages through TLR2

Bacterial species evolved evasive maneuvers to bypass their recognition by the receptors primarily TLRs of the innate immune cells. We have reported that 3 μg/ml of recombinant YopJ when provided extracellularly induced apoptosis in murine peritoneal macrophages in vitro. The present investigations demonstrate the role of TLR2 in apoptotic signals induced by rYopJ protein in murine peritoneal macrophages. The role of TLR2 in rYopJ induced macrophage apoptosis was shown by neutralization experiments and its co-immunoprecipitation with downstream molecule MyD88. The observed functional consequence of TLR2 neutralization were the inhibition of caspase-8 and caspase-3 activation, change in mitochondrial membrane potential (Δψm) and DNA fragmentation induced by rYopJ in macrophages. Further, rYopJ induced enhanced expression of IRAK-4, FADD, phosphorylation of IκB and p38 MAP kinase in macrophages. Pharmacological inhibitor of p38 MAP kinase and neutralization of TLR2 with neutralizing antibodies significantly inhibited the rYopJ induced caspases activation and DNA fragmentation, suggesting the possible involvement of TLR2 and p38 MAP kinase in rYopJ induced macrophages apoptosis.     

SB239063,新一代p38丝裂原活化蛋白激酶抑制剂在缺氧缺糖所致SHSY5Y细胞损伤中的作用

目的 探讨SB239063,新一代p38丝裂原活化蛋白激酶(p38MAPK)抑制剂在缺氧缺糖(OGD)所致SHSY5Y细胞损伤中的作用.方法 体外培养SHSY5Y神经母细胞瘤株,以OGD、SB239063(10μmol/L)处理,以MTT检测SHSY5Y细胞活性,以Western blot方法检测p38MAPK活性,应用HEt和fluo-3/AM的荧光强度测定OGD后SHSY5Y细胞超氧化物阴离子和钙离子的浓度.结果 SB239063能提高OGD后SHSY5Y细胞的活性(P<0.01),降低OGD后p38MAPK活性(P<0.05),HEt(P<0.05)和fluo-3/AM荧光强度(P<0.01).结论 SB239063通过抑制p38MAPK的激活,降低细胞内超氧阴离子的浓度,进而抑制细胞内钙超载,从而达到保护SHSY5Y细胞对抗OGD的细胞损害的作用.

Abstract：

Objective To investigate the neuroprotective effect of SB239063,the new p38 mitogen—activated protein kinase (MAPK) inhibitor on SHSY5Y neuronal cells against oxygen-glucose deprivation(OGD),and the mechanisms of the neuroprotective effect.Methods SHSY5Y neuroblastoma cells were exposed to OGD with or without SB239063 (10μmol/L),cell viability was measured by the MTF assay,activity of p38MAPK was measured by western blot,intracellular concentration of superoxide anion and calcium were evaluated via the fluorescence intensity of Het and fluo-3/AM. Resuits Compared with the OGD group.The MTT value was elevated significantly in the SB239063 group(P<0.01),the activitv of p38MAPK decreased significantly in the SB239063 group(P<0.01),the fluorescence intensity of Het(P<0.05)and fluo-3/AM(P<0.01)decreased significantly in the SB239063 group.Conclusion SB239063 protects SHSY5Y neuronal cells against OGD by inhibiting the activity of p38MAPK,then reducing the intracellular concentration of superoxide anion and calcium.     

丝裂原活化蛋白激酶(MAPK)抑制剂对人精子活动力的影响

<正>丝裂原活化蛋白激酶(MAPK)属于丝/苏氨酸蛋白激酶,有报道[1]其家族成员细胞外信号调节激酶(extracellular-signal regulated protein kinase,ERK)和p38MAPK定位于精子尾部中段,参与精子活动力的调节;17-β雌二醇可通过PI3K/Akt通路激活ERK,增加精子活动力,并且ERK是在     

Evidence that 5-hydroxytryptamine7 receptors play a role in the mediation of afferent transmission within the nucleus tractus solitarius in anaesthetized rats

Background and purpose:

Central 5-hydroxytryptamine (5-HT)-containing pathways utilizing 5-HT₇ receptors are known to be critical for the mediation of cardiovascular reflexes. The nucleus tractus solitarius (NTS) is a site involved in the integration of cardiovascular afferent information. The present experiments examined the involvement of the 5-HT₇ receptor in the processing of cardiovascular reflexes in the NTS.

Experimental approach:

In anaesthetized rats extracellular recordings were made from 104 NTS neurones that were excited by electrical stimulation of the vagus nerve and/or activation of cardiopulmonary afferents. Drugs were applied ionophoretically in the vicinity of these neurones.

Key results:

The non-selective 5-HT₇ receptor agonist 5-carboxamidotryptamine maleate (5-CT) applied to 78 neurones increased the firing rate in 18 by 59% and decreased it in 38 neurones by 47%. Similarly, the 5-HT_1A agonist 8-OH-DPAT applied to 20 neurones had an excitatory (8), inhibitory (7) or no effect (5) on the 20 neurones tested. In the presence of the 5-HT₇ antagonist SB 258719 the 5-CT excitation was attenuated. Furthermore, the excitatory response of NTS neurones evoked by electrical stimulation of the vagus nerve or activation of cardiopulmonary afferents with intra atrial phenylbiguanide was attenuated by SB 258719. The inhibitory action of 5-CT was unaffected by SB 258719 and the 5-HT_1A antagonist WAY-100635. WAY-100635 failed to have any effect on 5-CT and vagal afferent-evoked excitations.

Conclusions and implications:

Vagal afferent-evoked excitation of NTS neurones can be blocked by SB 258719, a selective 5-HT₇ antagonist. This observation further supports the involvement of 5-HT neurotransmission in NTS afferent processing.     

小鼠肺炎衣原体肺炎TLR2基因表达及信号传导机制的实验研究

目的 探讨小鼠感染肺炎衣原体后肺组织TOLL样受体(TLR)2的基因表达变化及其信号传导机制.方法 TLR4基因缺失小鼠(C3H/HeJ)96只,随机分为对照组、模型组、SB203580组和PDTC组,每组24只.每组分别按1、4、7、14 d各分4个小组,每小组6只.对照组鼻内接种二磷酸蔗糖(2sp)缓冲液,模型组和干预组均给予约4.0×106IFU/mL(0.04 mE)的肺炎衣原体鼻内接种,SB203580组和PDTC组在接种完肺炎衣原体后分别立即腹腔注射相应的p38蛋白激酶(p38MAPK)抑制剂SB203580(100 mg/kg)或核因子κB(NF-κB)抑制剂吡咯烷二硫氨基甲酸(PDTC)(50 mg/kg).分别于接种后第1、4、7及14 d处死小鼠,RT-PeR法检测肺组织TLR2 mRNA的表达,ELISA法测定肺组织匀浆肿瘤坏死因子α(TNF-α)的含量,同时观察肺组织病理变化.结果 小鼠感染肺炎衣原体后肺组织TLR2 mRNA表达迅速升高,以第4 d和第7 d明显,14 d以后开始下降.PDTC早期干预可在一定程度上抑制肺脏组织TLR2 mRNA表达,并在感染高峰期抑制明显.SB203580对小鼠肺组织TLR2 mRNA表达也有明显抑制.感染肺炎衣原体后,肺组织TNF-α表达水平显著高于正常组,SB203580和PDTC对小鼠肺组织TNF-α表达均有抑制作用,SB203580对TNF-α的抑制作用强于PDTC.结论 小鼠感染肺炎衣原体后,可引起TLR2表达的增加.对p38MAPK和NF-KB的干预均影响TLR2的表达以及炎症介质的释放,提示肺炎衣原体可能是通过TLR2/MAPK和TLR2/F-κB通路导致肺部炎症反应.     

Development of an improved canine model of percutaneous spinal cord compression injury by balloon catheter

The technique named detrended fluctuation analysis (DFA) has been used to reveal the presence of long-range temporal correlations (LRTC) and scaling behavior (SB) in electroencephalographic (EEG) recordings. The occurrence of these phenomena seems to be a salient characteristic of the healthy human brain and alterations in different pathologies has been described. Here we show how the filtering stages implemented in the systems for digital EEG influence the estimation of the DFA parameters used to characterize the brain signals. In consequence, we conclude that it is important to consider these filtering effects before interpreting the results obtained from digital EEG recordings.     

Randomized Comparison of FFR-Guided and Angiography-Guided Provisional Stenting of True Coronary Bifurcation Lesions: The DKCRUSH-VI Trial (Double Kissing Crush Versus Provisional Stenting Technique for Treatment of Coronary Bifurcation Lesions VI)

ObjectivesThis study sought to compare the outcomes of fractional flow reserve (FFR)–guided and angiography (Angio)–guided provisional side-branch (SB) stenting for true coronary bifurcation lesions.BackgroundAngio-guided provisional SB stenting after stenting of the main vessel provides favorable outcomes for the majority of coronary bifurcation lesions. Whether an FFR-guided provisional stenting approach is superior has not been studied.MethodsA total of 320 patients with single Medina 1,1,1 and 0,1,1 coronary bifurcation lesions undergoing stenting with a provisional SB approach were randomly assigned 1:1 to Angio-guided and FFR-guided groups. SB stenting was performed for Thrombolysis In Myocardial Infarction flow grade <3, ostial SB stenosis >70%, or greater than type A dissection after main vessel stenting in the Angio-guided group and for SB-FFR <0.80 in the FFR-guided group. The primary endpoint was the 1-year composite rate of major adverse cardiac events (cardiac death, myocardial infarction, and clinically driven target vessel revascularization).ResultsComparing the Angio-guided and FFR-guided groups, treatment of the SB (balloon or stenting) was performed in 63.1% and 56.3% of lesions respectively (p = 0.07); stenting of the SB was attempted in 38.1% and 25.9%, respectively (p = 0.01); and, when attempted, stenting was successful in 83.6% and 73.3% of SBs, respectively (p = 0.01). The 1-year composite major adverse cardiac event rate was 18.1% in both groups (hazard ratio: 0.91, 95% confidence interval: 0.48 to 1.88; p = 1.00). The 1-year target vessel revascularization and stent thrombosis rates were 6.9% and 5.6% (p = 0.82) and 1.3% and 0.6% (p = 0.56) in the Angio-guided and FFR-guided groups, respectively.ConclusionsIn this multicenter, randomized trial, angiographic and FFR guidance of provisional SB stenting of true coronary bifurcation lesions provided similar 1-year clinical outcomes. (Randomized Study on DK Crush Technique Versus Provisional Stenting Technique for Coronary Artery Bifurcation Lesions; ChiCTR-TRC-07000015)     

Human Antibody Fragments Specific for the Epidermal Growth Factor Receptor Selected from Large Non-immunised Phage Display Libraries

Antibodies to EGFR have been shown to display anti-tumour effects mediated in part by inhibition of cellular proliferation and angiogenesis, and by enhancement of apoptosis. Humanised antibodies are preferred for clinical use to reduce complications with HAMA and HAHA responses frequently seen with murine and chimaeric antibodies. We have used depletion and subtractive selection strategies on cells expressing the EGFR to sample two large antibody fragment phage display libraries for the presence of human antibodies which are specific for the EGFR. Four Fab fragments and six scFv fragments were identified, with affinities of up to 2.2 nM as determined by BIAcore analysis using global fitting of the binding curves to obtain the individual rate constants (k_a and k_d). This overall approach offers a generic screening method for the identification of growth factor specific antibodies and antibody fragments from large expression libraries and has potential for the rapid development of new therapeutic and diagnostic reagents.