代谢组学用于研究基因改变对大肠杆菌代谢的影响

代谢组学的出现使我们能从代谢物水平上分析产生或者不产生可见的表型变化的基因变化。代 谢组学在植物研究中的应用很多，在微生物研究中则还没有太多的系统报道。本工作将气相色谱技 术的微生物代谢组学的分析平台，用于研究基因改变对大肠杆菌代谢的影响。 以E.coli1.1566 、基因敲除突变株（DC100△sdhAB和 DC101△ackA-pta）为实验菌株，首先提 取细胞内小分子的化合物，采用N,O-双三甲基硅基三氟乙酰胺（BSTFA）1%TMCS试剂对其衍生， 再进行GC分析，最后多变量数据分析。 利用该平台对大肠杆菌原始菌株与基因敲除突变株进行区分，结果显示此平台能有效区分不同 菌株，并得到了潜在的标记物。E.coli1.1566 与DC101△ackA-pta 比较，大肠杆菌敲除ackA-pta 基因 后，琥珀酸和嘧啶相对含量升高，脯氨酸和天冬氨酸相对含量下降。E.coli1.1566 与DC100△sdhAB 比较大肠杆菌原始菌株上敲除sdhAB 基因后，磷酸和天冬氨酸含量下降，谷氨酸、脯氨酸和琥珀酸 含量上升。结合大肠杆菌的代谢途径分析，得到的结果与代谢组学所得的结果一致。 本研究为以后比较已知功能基因的缺失与未知基因功能缺失的相似性提供了快速分析平台，显 示代谢组学在微生物代谢研究中具有广阔的应用前景

1,5,8-trihydroxy-3-methoxy-xanthone对大鼠局灶性脑缺血再灌注损伤的保护作用

目的　研究 1, 5, 8 trihydroxy 3 methoxy xanthoneXanth对大鼠局灶性脑缺血再灌注损伤的保护作用。方法　采用线栓法阻断大脑中动脉 (MCA)血流,造成局灶性脑缺血再灌注模型;评价大鼠行为功能、测定脑梗死体积及脑血清中丙二醛(MDA)含量、超氧化物歧化酶 (SOD)、谷胱甘肽过氧化物酶 (GSH Px)活性。结果　 1, 5, 8 trihydroxy 3 methoxy xanthone对大鼠脑缺血再灌注的模型组与假手术组相比,MDA含量升高 (P<0 05 ),S

Mental health of elderly victims in relocation sites four months after the 5·12 earthquake

目的评估5.12地震后4个月安县板房区老年人的心理健康状况,并探讨其影响因素。方法利用自编受灾情况调查问卷、中国心理健康量表(老年版)(CMHI-E)、幸福感量表(MUNSH)和流调中心用抑郁量表(CES-D),调查绵阳市两个安置板房区290位老年人。结果灾区老年人的心理健康水平和幸福感水平均低于对照样本(P<0.001);抑郁水平高于对照样本(P<0.001);心理健康得分和幸福感正相关(r=0.61,P<0.01);心理健康得分和抑郁得分负相关(r=-0.59,P<0.01)。多元回归分析显示影响灾区老年人心理健康的主要因素有亲属遇难人数、财产损失状况和年龄。结论重灾区老年人的心理健康状况较差,幸福感水平较低,抑郁程度较高。遇难的亲属越多、年龄越大、财产损失越严重,老人的心理健康状况越差

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