眼镜蛇毒因子抑制补体激活对脓毒症大鼠血清细胞因子的影响

目的:观察眼镜蛇毒因子(cobra venom factor,CVF)对脓毒症大鼠外周血中肿瘤坏死因子-α(TNF-α)、白介素-6(IL-6)和白介素-10(IL-10)的影响。方法:选取清洁级雄性SD大鼠144只,按照随机数字表法将大鼠分为A组(假手术组)、B组(脓毒症组)、C组(CVF预处理组),各48只;各组按照标本采集点的不同又分为术后2、4、8、12、16、24 h六个时间点亚组,各8只。B、C组采用盲肠结扎穿孔术(CLP)制作脓毒症大鼠模型;C组大鼠在CLP术前静脉注射CVF,而A、B组静脉注射等量0.9%氯化钠溶液。观察术后大鼠一般情况及腹腔情况,比较各组术后不同时间点的TNF-α、IL-6和IL-10水平变化。结果:C组大鼠脓毒症反应较B组明显减轻;除术后8 h外,C组术后其他时间点TNF-α水平均低于B组(P<0.05),其中B组术后2 h时TNF-α迅速升高达峰然后下降,但是术后12 h再次升高出现第二个峰值,C组术后4 h较2 h迅速下降,术后8 h再次升高出现第二个峰值;除术后16 h外,C组术后其他时间IL-6水平均低于B组(P<0.01);除术后2、24 h外,C组血清IL-10水平均高于B组(P<0.05),而且术后8、16 h两次达到峰值,呈双峰变化。结论:CVF可以有效维持促炎细胞因子(TNF-α、IL-6)和抗炎细胞因子(IL-10)的平衡并明显抑制脓毒症大鼠的炎症反应,同时TNF-α及IL-10的\"双峰现象\"也为免疫平衡理论及PICS提供了理论依据。江西省自然科学基金资助项目(0440083

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies