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产气荚膜梭菌Alpha毒素突变体的表达及单克隆抗体制备
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作者 韩凤烨 刘莹 +7 位作者 潘晨帆 张乾义 陈小云 朱真 印春生 温永俊 王凤雪 杜吉革 《中国畜牧兽医》 北大核心 2025年第1期442-450,共9页
[目的]获得产气荚膜梭菌Alpha毒素(Clostridium perfringens alpha-toxin, CPA)的重组突变体,评价其毒力和抗原性,进而制备针对CPA的单克隆抗体,并评价单克隆抗体特性。[方法]通过人工合成含6个氨基酸突变(第56和130位的天冬氨酸突变为... [目的]获得产气荚膜梭菌Alpha毒素(Clostridium perfringens alpha-toxin, CPA)的重组突变体,评价其毒力和抗原性,进而制备针对CPA的单克隆抗体,并评价单克隆抗体特性。[方法]通过人工合成含6个氨基酸突变(第56和130位的天冬氨酸突变为甘氨酸、第275、307和331位的酪氨酸突变为苯丙氨酸、第336位的天冬氨酸突变为天冬酰胺)的CPA基因片段,并将其克隆至pET-30a(+)载体,转化大肠杆菌BL21(DE3)感受态细胞进行诱导表达与纯化,获得重组蛋白rCPA_(m6),并检测其毒力与免疫原性。将rCPA_(m6)作为包被抗原建立CPA抗体的间接ELISA检测方法,并用灭活的天然CPA作为免疫原按照常规方法免疫BALB/c小鼠,制备单克隆抗体,对其功能进行鉴定。[结果]重组蛋白rCPA_(m6)在大肠杆菌BL21(DE3)感受态中能够以可溶性和包涵体两种形式表达。毒力测定结果显示,100μg/只rCPA_(m6)攻毒后,小鼠全部存活。免疫原性分析结果显示,1×最小致死量(MLD)的天然CPA攻毒后,对照组小鼠全部死亡,10和20μg/只rCPA_(m6)免疫组小鼠存活率为100%。利用rCPA_(m6)成功建立了CPA抗体的间接ELISA检测方法,并筛选获得4株分泌抗CPA的单克隆抗体杂交瘤细胞株,分别命名为6E3、6B8、10A11、13D10,且4种细胞上清抗体效价均≥1∶3 200,其中单克隆抗体6B8细胞上清能中和天然CPA,且能与rCPA_(m6)发生反应。[结论]试验成功获得具有良好的安全性和免疫原性的重组蛋白rCPA_(m6),制备的CPA单克隆抗体6B8具有一定的中和活性及较高的特异性和敏感性。研究结果为CPA亚单位疫苗的研制提供了候选抗原,同时为CPA中毒症的治疗以及抗原/抗体检测方法的建立提供了物质基础。 展开更多
关键词 产气荚膜梭菌alpha毒素(CPA) 突变体 原核表达 单克隆抗体
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Alpha-synuclein in mitochondrial dysfunction:opportunities or obstacles
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作者 Shermali Gunawardena 《Neural Regeneration Research》 SCIE CAS 2025年第1期197-198,共2页
Recent work suggests a link betweenα-synuclein(α-syn)and mitochondrial dysfunction;however,the mechanisms of howα-syn influences mitochondrial function are still unclear.Most notably,whetherα-syn plays a direct ro... Recent work suggests a link betweenα-synuclein(α-syn)and mitochondrial dysfunction;however,the mechanisms of howα-syn influences mitochondrial function are still unclear.Most notably,whetherα-syn plays a direct role during mitochondrial function and/or whether diseasedα-syn-mediated mitochondrial dysfunction is a potential modifiable risk factor in Parkinson’s disease(PD)is unknown.To date,mutations in more than eight genes cause familial PD(fPD)and have functions in diverse pathways including synaptic homeostasis,mitochondria maintenance,autophagy/lysosome,and ubiquitin-proteasome pathways. 展开更多
关键词 DYSFUNCTION HOMEOSTASIS alpha
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Alpha-7 nicotinic acetylcholine receptor agonist treatment in a rat model of Huntington's disease and involvement of heme oxygenase-1 被引量:3
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作者 Laura Foucault-Fruchard Claire Tronel +4 位作者 Sylvie Bodard Zuhal Gulhan Julie Busson Sylvie Chalon Daniel Antier 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第4期737-741,共5页
Neuroinflammation is a common element involved in the pathophysiology of neurodegenerative diseases.We recently reported that repeated alpha-7 nicotinic acetylcholine receptor(α7 n ACh R) activations by a potent ag... Neuroinflammation is a common element involved in the pathophysiology of neurodegenerative diseases.We recently reported that repeated alpha-7 nicotinic acetylcholine receptor(α7 n ACh R) activations by a potent agonist such as PHA 543613 in quinolinic acid-injured rats exhibited protective effects on neurons.To further investigate the underlying mechanism,we established rat models of early-stage Huntington's disease by injection of quinolinic acid into the right striatum and then intraperitoneally injected 12 mg/kg PHA 543613 or sterile water,twice a day during 4 days.Western blot assay results showed that the expression of heme oxygenase-1(HO-1),the key component of the cholinergic anti-inflammatory pathway,in the right striatum of rat models of Huntington's disease subjected to intraperitoneal injection of PHA 543613 for 4 days was significantly increased compared to the control rats receiving intraperitoneal injection of sterile water,and that the increase in HO-1 expression was independent of change in α7 n ACh R expression.These findings suggest that HO-1 expression is unrelated to α7 n ACh R density and the increase in HO-1 expression likely contributes to α7 n ACh R activation-related neuroprotective effect in early-stage Huntington's disease. 展开更多
关键词 alpha 7 nicotinic receptor PHA 543613 quinolinic acid cholinergic anti-inflammatory pathway NEUROINFLAMMATION neurodegenerative disease
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Protein induced by vitamin K absence or antagonist-Ⅱ versus alpha-fetoprotein in the diagnosis of hepatocellular carcinoma: A systematic review with meta-analysis 被引量:40
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作者 Hao Xing Yi-Jie Zheng +5 位作者 Jun Han Han Zhang Zhen-Li Li Wan-Yee Lau Feng Shen Tian Yang 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2018年第6期487-495,共9页
Background: As a promising biomarker of hepatocellular carcinoma(HCC), protein induced by vitamin K absence or antagonist-Ⅱ(PIVKA-Ⅱ) has been studied extensively. However, its diagnostic capability varies across HCC... Background: As a promising biomarker of hepatocellular carcinoma(HCC), protein induced by vitamin K absence or antagonist-Ⅱ(PIVKA-Ⅱ) has been studied extensively. However, its diagnostic capability varies across HCC studies. This study aimed to compare the performance of PIVKA-Ⅱ with alpha-fetoprotein(AFP) in the diagnosis of HCC. Data sources: A systematic literature search was conducted to identify the studies from MEDLINE, Embase and Cochrane Library Databases, which were published up to December 20, 2017 to compare the diagnostic capability of PIVKA-Ⅱ and AFP for HCC. The data were pooled using random effects model. Pooled sensitivity and specificity were calculated. Summary receiver operating characteristic curve(ROC) was employed to evaluate the diagnostic accuracy of each marker. Results: Thirty-one studies were included. The pooled sensitivity(95% CI) of PIVKA-Ⅱ and AFP was 0.66(0.65–0.68) and 0.66(0.65–0.67), respectively in diagnosis of HCC; and the corresponding pooled specificity(95% CI) was 0.89(0.88–0.90) and 0.84(0.83–0.85), respectively. The area under the ROC curve(AUC) of PIVKA-Ⅱ and AFP was 0.856(0.817–0.895) and 0.770(0.728–0.811), respectively. Subgroup analysis showed that PIVKA-Ⅱ was superior to AFP in terms of the AUC for both small HCC( < 3 cm) [0.863(0.825–0.901) vs 0.717(0.658–0.776)] and large HCC( ≥ 3 cm) [0.854(0.811–0.897) vs 0.729(0.682–0.776)]; for American [0.926(0.897–0.955) vs 0.698(0.594–0.662)], European [0.772(0.743–0.801) vs 0.628(0.594–0.662)], Asian [0.838(0.812–0.864) vs 0.785(0.764–0.806)] and African [0.812(0.794–0.840) vs 0.721(0.675–0.767)] HCC patients; and for HBV-related [0.909(0.866–0.951) vs 0.714(0.673–0.755)] and mixed-etiology [0.847(0.821–0.873) vs 0.794(0.772–0.816)] HCC. Conclusion: This meta-analysis indicates that PIVKA-Ⅱ is better than AFP in terms of the accuracy for diagnosing HCC, regardless of tumor size, patient ethnic group, or HCC etiology. 展开更多
关键词 Hepatocellular carcinoma Meta-analyses Protein induced by vitamin K absence or antagonist-Ⅱ alpha-FETOPROTEIN
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Altered expression of metabotropic glutamate receptor 1 alpha after acute diffuse brain injury Effect of the competitive antagonist 1-aminoindan-1, 5-dicarboxylic acid
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作者 Fei Cao Mantao Chen +3 位作者 Gu Li Ke Ye Xin Huang Xiujue Zheng 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第2期119-124,共6页
The diffuse brain injury model was conducted in Sprague-Dawley rats, according to Marmarou's free-fall attack. The water content in brain tissue, expression of metabotropic glutamate receptor la mRNA and protein were... The diffuse brain injury model was conducted in Sprague-Dawley rats, according to Marmarou's free-fall attack. The water content in brain tissue, expression of metabotropic glutamate receptor la mRNA and protein were significantly increased after injury, reached a peak at 24 hours, and then gradually decreased. After treatment with the competitive antagonist of metabotropic glutamate receptor la, (RS)-l-aminoindan-1,5-dicarboxylic acid, the water content of brain tissues decreased between 12-72 hours after injury, and neurological behaviors improved at 2 weeks. These experimental findings suggest that the 1-aminoindan-1, 5-dicarboxylic acid may result in marked neuroprotection against diffuse brain injury. 展开更多
关键词 diffuse brain injury in vivo animal model metabotropic glutamate receptor 1 alpha 1-aminoindan-1 5-dicarboxylic acid
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慢性失眠合并轻度认知功能障碍老年患者顶枕叶alpha脑电频谱特征研究
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作者 郭振兴 白林鑫 +3 位作者 张琳 高佳慧 饶婷 刘志臻 《康复学报》 CSCD 2024年第6期597-603,共7页
目的分析慢性失眠合并轻度认知功能障碍(MCI)老年患者顶枕叶alpha脑电频谱特征。方法选择2019年6月—2020年12月福建省福州市鼓东、温泉社区老年受试者80例,其中健康对照组(HC组)30例、慢性失眠组(CI组)20例、慢性失眠合并MCI组(CI-MCI... 目的分析慢性失眠合并轻度认知功能障碍(MCI)老年患者顶枕叶alpha脑电频谱特征。方法选择2019年6月—2020年12月福建省福州市鼓东、温泉社区老年受试者80例,其中健康对照组(HC组)30例、慢性失眠组(CI组)20例、慢性失眠合并MCI组(CI-MCI组)30例。采用匹兹堡睡眠质量指数(PSQI)评估睡眠质量;采用福州版蒙特利尔认知评估量表(MoCA)评估受试者认知功能(视空间执行、命名、注意力、言语流畅性、抽象力、延迟回忆和定向力);采用Neuroscan 64导联脑电仪同步脑电记录系统采集日间静息态脑电波(EEG),对比顶枕叶alpha(8~13 Hz)各通道功率值的差异及变化趋势;分析顶枕叶alpha频谱功率的改变与认知功能的相关性。结果(1)PSQI评分:与HC组比较,CI-MCI组日间功能障碍评分明显升高,差异具有统计学意义(P<0.05);CI组、CI-MCI组PSQI总分、睡眠质量、入睡时间、睡眠时间、睡眠效率、睡眠障碍评分均明显升高,催眠药物评分明显降低,差异均具有统计学意义(P<0.05)。(2)MoCA评分:与HC组、CI组比较,CI-MCI组MoCA总分、视空间执行、命名、注意力、语言流畅性、抽象力、延迟回忆、定向力评分均明显降低,差异均具有统计学意义(P<0.05)。(3)EEG频谱特征:与HC组比较,CI-MCI组顶枕叶P1、P6、POZ、PO4、PO6 alpha频谱功率均明显增强,差异均具有统计学意义(P<0.05);与HC组比较,CI-MCI组顶枕叶alpha频谱地形图呈现出频谱功率较强的现象。(4)顶枕叶alpha频谱功率的改变与认知功能的相关性:P6右顶叶alpha频谱功率(r=0.444,P=0.023)、POZ顶枕叶alpha频谱功率(r=0.444,P=0.023)、PO4右顶枕叶alpha频谱功率(r=0.478,P=0.014)均与视空间执行功能呈正相关关系。结论顶枕叶alpha频谱功率变化是慢性失眠合并MCI老年患者认知功能损伤的表现;顶枕叶alpha频谱功率可调节慢性失眠合并MCI老年患者的认知功能。 展开更多
关键词 慢性失眠 轻度认知功能障碍 alpha频谱 顶枕叶 老年患者
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Diagnostic value of gamma-glutamyltransferase/aspartate aminotransferase ratio, protein induced by vitamin K absence or antagonist II, and alpha-fetoprotein in hepatitis B virus-related hepatocellular carcinoma 被引量:19
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作者 Qiang Wang Qi Chen +6 位作者 Xia Zhang Xiao-Lan Lu Qin Du Tao Zhu Guo-Yuan Zhang Dong-Sheng Wang Qu-Ming Fan 《World Journal of Gastroenterology》 SCIE CAS 2019年第36期5515-5529,共15页
BACKGROUND Researchers have investigated the diagnostic value of protein induced by vitamin K absence or antagonist II (PIVKA-II) and alpha-fetoprotein (AFP) in hepatitis B virus (HBV)-related hepatocellular carcinoma... BACKGROUND Researchers have investigated the diagnostic value of protein induced by vitamin K absence or antagonist II (PIVKA-II) and alpha-fetoprotein (AFP) in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC), and obtained abundant clinical diagnostic data. However, PIVKA-II and AFP have unsatisfactory specificity and sensitivity in the diagnosis of early-stage HBV-related HCC. Gamma-glutamyltransferase (γ-GT) and aspartate aminotransferase (AST) are common biomarkers for evaluating liver function, and we hypothesized that the γ-GT/AST ratio in combination with PIVKA-II and AFP would improve the diagnosis of early-stage HBV-related HCC. AIM To evaluate the diagnostic value of γ-GT/AST ratio alone or in combination with PIVKA-II and AFP in HBV-related HCC. METHODS Serum levels of γ-GT, AST, PIVKA-II, and AFP were detected and analysed in 176 patients with HBV-related HCC and in 359 patients with chronic hepatitis B. According to tumour size and serum level of HBV DNA, HBV-related HCC patients were divided into the following categories: Early-stage HCC patients, HCC patients, HBV DNA positive (HBV DNA+) HCC patients, and HBV DNA negative (HBV DNA-) HCC patients. Receiver-operating characteristic (ROC) curves were used to analyse and compare the diagnostic value of the single and combined detection of various biomarkers in different types of HBV-related HCC. RESULTS Tumour size was positively correlated with serum levels of PIVKA-II and AFP in HCC patients (r = 0.529, aP < 0.001 and r = 0.270, bP < 0.001, respectively), but there was no correlation between tumour size and the γ-GT/AST ratio (r = 0.073, P = 0.336). The areas under the receiver-operating characteristic curves (AUROCs) of the γ-GT/AST ratio in early-stage HCC patients, HBV DNA+ HCC patients and HBV DNA- HCC patients were not significantly different from that in the total HCC patients (0.754, 0.802, and 0.705 vs 0.779, respectively;P > 0.05). When PIVKA-II was combined with the γ-GT/AST ratio in the diagnosis of earlystage HCC, HCC, and HBV DNA+ HCC, the AUROCs of PIVKA-II increased, with values of 0.857 vs 0.835, 0.925 vs 0.913, and 0.958 vs 0.954, respectively. When AFP was combined with the γ-GT/AST ratio in the diagnosis of early-stage HCC, HCC, HBV DNA+ HCC, and HBV DNA- HCC, the AUROCs of AFP increased, with values of 0.757 vs 0.621, 0.837 vs 0.744, 0.868 vs 0.757, and 0.840 vs 0.828, respectively. CONCLUSION The γ-GT/AST ratio may be better than PIVKA-II and AFP in the diagnosis of early-stage HBV-related HCC, and its combination with PIVKA-II and AFP can improve the diagnostic value for HBV-related HCC. 展开更多
关键词 GAMMA-GLUTAMYLTRANSFERASE Aspartate aminotransferase PROTEIN induced by vitamin K ABSENCE or ANTagonIST II alpha-FETOPROTEIN Hepatitis B virus Hepatocellular carcinoma
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阿尔茨海默病病变相关脑区Pgc-1alpha敲除小鼠模型的构建
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作者 史厚珍 张维君 +4 位作者 翟鸿儒 王贻界 王雨欣 刘子重 王佳 《江苏大学学报(医学版)》 CAS 2024年第5期423-427,450,共6页
目的:构建在阿尔茨海默病(Alzheimer′s disease,AD)病变相关脑区过氧化物酶体增殖物激活受体γ辅激活因子-1α(peroxisome proliferator-activated receptorγcoactivator-1 alpha,Pgc-1alpha)敲除小鼠。方法:引入Pgc-1alpha条件性敲... 目的:构建在阿尔茨海默病(Alzheimer′s disease,AD)病变相关脑区过氧化物酶体增殖物激活受体γ辅激活因子-1α(peroxisome proliferator-activated receptorγcoactivator-1 alpha,Pgc-1alpha)敲除小鼠。方法:引入Pgc-1alpha条件性敲除杂合子小鼠(Pgc-1alphafl/+),通过自交获得Pgc-1alpha条件性敲除纯合子小鼠(Pgc-1alphafl/fl)。将Pgc-1alphafl/fl纯合子小鼠和在AD病变脑区(皮层、海马)特异性表达Cre重组酶的Cre工具鼠(Calb1-Cre)杂交,提取子代转基因小鼠基因组DNA,行PCR鉴定,确定其基因型;采用蛋白免疫印迹技术检测转基因小鼠与野生型小鼠脑区及肾脏PGC-1α蛋白表达。结果:双重PCR鉴定结果显示,同时扩增出400 bp及444 bp条带的小鼠为AD病变脑区Pgc-1alpha敲除纯合子小鼠(Pgc-1alphafl/fl::Calb1-Cre,Pgc-1alpha-/-)。蛋白免疫印迹结果显示,与野生型小鼠相比,条件性敲除小鼠脑区PGC-1α蛋白表达明显减少(P<0.05)。结论:成功构建在AD病变相关脑区Pgc-1alpha敲除小鼠。 展开更多
关键词 过氧化物酶体增殖物激活受体γ辅激活因子-1α(Pgc-1alpha) 条件性敲除 小鼠 阿尔茨海默病 皮层 海马
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基于改进Alpha Shape算法的点云数据岛屿边界提取
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作者 宋晓辉 熊祖雄 +2 位作者 张炎 吕富强 韦建林 《海洋测绘》 CSCD 北大核心 2024年第1期58-62,共5页
针对机载LiDAR点云的岛屿岸线提取过程复杂、附属岛屿岸线难以提取等问题,提出一种基于改进Alpha Shape算法的点云数据岛屿边界提取方法。首先利用布料模拟滤波算法剔除非岛屿点云数据,通过欧式聚类进行不同岛屿的提取,再将岛屿点云数... 针对机载LiDAR点云的岛屿岸线提取过程复杂、附属岛屿岸线难以提取等问题,提出一种基于改进Alpha Shape算法的点云数据岛屿边界提取方法。首先利用布料模拟滤波算法剔除非岛屿点云数据,通过欧式聚类进行不同岛屿的提取,再将岛屿点云数据投影至二维平面,并根据岛屿点云构建格网。在此基础上使用自适应Alpha Shape算法,对提取出的岛屿点云进行边界提取,即可得到岛屿的岸线轮廓。选取新西兰的玛提尤/萨姆斯岛作为研究区域,并将本文算法与Alpha Shape算法进行对比,结果表明:本文算法提取岛屿边界点云的精准度为97.78%,可以准确地提取岛屿岸线,为海岛规划提供参考。 展开更多
关键词 摄影测量 机载LiDAR点云 边界提取 欧式聚类 自适应alpha Shape
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Alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist inhibits apoptosis of retinal ganglion cells in a rabbit model of optic nerve injury 被引量:1
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作者 Ruijia Wang Xinping Luan Yiti Mu Hongyu Jia Jingxuan Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第10期731-735,共5页
A rabbit model of traumatic optic nerve injury, established by occlusion of the optic nerve using a vascular clamp, was used to investigate the effects of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid recep... A rabbit model of traumatic optic nerve injury, established by occlusion of the optic nerve using a vascular clamp, was used to investigate the effects of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist GYKI 52466 on apoptosis of retinal ganglion cells following nerve injury. Hematoxylin-eosin staining and a terminal deoxynucleotidyl transferase dUTP nick end labeling assay showed that retinal ganglion cells gradually decreased with increasing time of optic nerve injury, while GYKI 52466 could inhibit this process. The results demonstrate that following acute optic nerve injury, apoptosis of retinal ganglion cells is a programmed process, which can be inhibited by the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist. 展开更多
关键词 optic nerve injury retinal ganglion cells GLUTAMATE alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor
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Alpha7 nicotinic receptors as potential theranostic targets for experimental stroke
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作者 Maider Garbizu Laura Aguado Abraham Martín 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期939-940,共2页
Inflammatory reflex and cholinergic anti-inflammatory pathway:Innate immune system triggers a local inflammatory response following an injury or a pathogen invasion.Likewise,this inflammatory response is limited by ra... Inflammatory reflex and cholinergic anti-inflammatory pathway:Innate immune system triggers a local inflammatory response following an injury or a pathogen invasion.Likewise,this inflammatory response is limited by rapid,localized,and adaptive anti-inflammatory responses which are crucial for maintaining homeostasis.Hence,the loss of these responses converts a limited and protective inflammatory response into an excessive and harmful response.Anti-inflammatory responses are integrated into the central nervous system,since the central nervous system accumulates information about harmful events,activates defenses,and builds memory for survival.At the same time,it has been demonstrated that hypothalamic neuronal signaling can be altered by inflammation in peripheral tissues.Additionally,immune cells release neuropeptides and neurotransmitters such as acetylcholine(ACh),the main neurotransmitter of the parasympathetic autonomic nervous system,evidencing the communication between the immune and nervous systems(Tracey,2002). 展开更多
关键词 protective INVASION alpha
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数学计算法和软件拟合法在虚拟和真实alpha粒子能损测量Mylar膜厚度实验中的比较
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作者 王媛 梅波 +2 位作者 薛玉琪 朱凡 杨莉莉 《大学物理实验》 2024年第4期89-94,共6页
根据中山大学物理与天文学院近代物理实验虚拟核实验连续三个年级的本科生实验报告,发现学生在用数学公式计算Mylar膜厚度时,与理论值出现较大误差,各年级的平均相对误差分别为445.02%、335.45%和519.92%。为了查找误差原因,做了真实核... 根据中山大学物理与天文学院近代物理实验虚拟核实验连续三个年级的本科生实验报告,发现学生在用数学公式计算Mylar膜厚度时,与理论值出现较大误差,各年级的平均相对误差分别为445.02%、335.45%和519.92%。为了查找误差原因,做了真实核实验并依旧采用数学计算方法计算Mylar膜厚度,发现仍旧与理论值出现较大误差,相对误差值为207.72%。而采用Srim软件计算虚拟核实验Mylar膜厚度和真实核实验Mylar膜厚度时,相对误差很小,分别为7.47%和20.1%。从而判定,用数学组合公式在计算多原子化合物Mylar膜时,不准确度较高,误差较大。 展开更多
关键词 虚拟alpha实验 Mylar膜厚度 真实alpha实验 计算薄膜厚度 Srim软件
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Numerical study of alpha particle loss with toroidal field ripple based on CFETR steady-state scenario
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作者 李钮琦 徐颖峰 +1 位作者 钟方川 张德兵 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期503-510,共8页
Effects of plasma equilibrium parameters on the alpha particle loss with the toroidal field ripple based on the CFETR steady-state scenario have been numerically investigated by the orbit-following code GYCAVA. It is ... Effects of plasma equilibrium parameters on the alpha particle loss with the toroidal field ripple based on the CFETR steady-state scenario have been numerically investigated by the orbit-following code GYCAVA. It is found that alpha particle losses decrease and loss regions become narrower with the plasma current increasing or with the magnetic field decreasing. It is because the ripple stochastic transport and the ripple well loss of alpha particle are reduced with the safety factor decreasing. Decrease of the plasma density and temperature can reduce alpha particle losses due to enhancement of the slowing-down effect. The direction of the toroidal magnetic field can significantly affect heat loads induced by lost alpha particle. The vertical asymmetry of heat loads induced by the clockwise and counter-clockwise toroidal magnetic fields are due to the fact that the ripple distribution is asymmetric about the mid-plane, which can be explained by the typical orbits of alpha particle. The maximal heat load of alpha particle for the clockwise toroidal magnetic field is much smaller than that for the counter-clockwise one. 展开更多
关键词 alpha particle loss RIPPLE orbit-following TOKAMAK
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Hydrographic Characteristics and Oceanic Heat Flux in the Upper Arctic Ocean over the Alpha Ridge Observed by the DTOP Platform in 2018 and 2021
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作者 WANG Yongjun LI Tao 《Journal of Ocean University of China》 CAS CSCD 2024年第2期304-316,共13页
In 2018 and 2021,the Drift-Towing Ocean Profilers(DTOP)provided extensive temperature and salinity data on the upper 120m ocean through their drifts over the Alpha Ridge north of the Canada Basin.The thickness and tem... In 2018 and 2021,the Drift-Towing Ocean Profilers(DTOP)provided extensive temperature and salinity data on the upper 120m ocean through their drifts over the Alpha Ridge north of the Canada Basin.The thickness and temperature maximum of Alaska Coastal Water(ACW)ranged from 20m to 40m and-1.5℃to-0.8℃,respectively,and the salinity generally maintained from 30.2 to 32.5.Comparison with World Ocean Atlas 2018’s climatology manifested a 40m-thick and warm ACW roughly ex-ceeding the temperature maximum by 0.4–0.5℃in June–August 2021.This anomalously warm ACW was highly related to the ex-pansion of the Beaufort Gyre in the negative Arctic Oscillation phase.During summer,the under-ice oceanic heat flux F_(w)^(OHF)was elevated,with a maximum value of above 25Wm^(-2).F_(w)^(OHF)was typically low in the freezing season,with an average value of 1.2Wm^(-2).The estimates of upward heat flux contributed by ACW to the sea ice bottom F_(w)^(OHF)were in the range of 3–4Wm^(-2)in June–August 2021,when ACW contained a heat content of more than 80MJm^(-2).The heat loss over this period was driven by a weak stratification upon the ACW layer associated with a surface mixed layer(SML)approaching the ACW core.After autumn,F_(w)^(OHF)was reduced(<2 Wm^(-2))except during rare events when it elevated F_(w)^(OHF)slightly.In addition,the intensive and widespread Ekman suction,which created a violent upwelling north of the Canada Basin,was largely responsible for the substantial cooling and thinning of the ACW layer in the summer of 2021. 展开更多
关键词 Arctic Ocean oceanic heat flux Alaska Coastal Water alpha Ridge
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Gross Alpha and Beta Activities and Related Lifetime Risks Assessment Due to Ingestion of Drinking Water from Different Sources in the District of Abidjan, Cote d’Ivoire
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作者 Ponaho Claude Kezo Issa Konate Dabo Salif Ignace Agba 《World Journal of Nuclear Science and Technology》 CAS 2024年第1期86-96,共11页
Drinking good quality water is essential for better health. It is therefore essential to assess the radiological quality of all water consumed in the District of Abidjan in order to prevent related hazards. Thus, the ... Drinking good quality water is essential for better health. It is therefore essential to assess the radiological quality of all water consumed in the District of Abidjan in order to prevent related hazards. Thus, the objective of this study was to assess the risk of cancer due to the ingestion of alpha and beta emitting radionuclides in the different types of water consumed in the region. A total of 63 water samples with 43 tap water samples, 5 bottled mineral water and 15 sachet water samples was collected and taken to GAEC laboratory for analysis. The low background Gas-less Automatic Alpha/Beta counting system (Canberra iMatic<sup>TM</sup>) was used to determine alpha and beta activity concentrations. Activity concentrations of both gross alpha and gross beta obtained in water sample were respectively lower than the WHO recommended limits of 0.1 Bq/l and 1 Bq/l. Also, the annual effective dose and total equivalent effective dose found in mineral bottled water samples were higher than in other types of water. The assessment of radiological lifetime risk has shown values of cancer risk due to ingestion alpha and beta emitters lower than recommended limit. These results indicate that there is no health hazard associated to consumption of water in the District of Abidjan. 展开更多
关键词 Gross alpha and Beta Activities Drinking Water Effective Dose Radiological Lifetime Risks
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Evaluation of angiotensin converting enzyme insertion/deletion, alpha adducin (ADD1) G460W, and IL-10 gene polymorphisms, and determination of prognostic effects in idiopathic sudden sensorineural hearing loss
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作者 Vural Akın Mehmet Emre Sivrice +4 位作者 Kuyas Hekimler Oztürk Hasan Yasan Mustafa Tüz Erdogan Okur Yusuf Çagdas Kumbul 《Journal of Otology》 CAS CSCD 2024年第2期97-105,共9页
Objective:The aim of this study was to examine angiotensin converting enzyme(ACE)insertion/deletion,alpha adducin,and interleukin-10(IL-10)gene polymorphisms(GPs)in terms of both idiopathic sudden sensorineural hearin... Objective:The aim of this study was to examine angiotensin converting enzyme(ACE)insertion/deletion,alpha adducin,and interleukin-10(IL-10)gene polymorphisms(GPs)in terms of both idiopathic sudden sensorineural hearing loss(ISSNHL)risk and their potential prognostic effects.Methods:The study group consisted of 70 patients and the control group consisted of 50 patients.Venous blood samples were analyzed for relevant GPs via kompetitive allele-specific polymerase chain reaction.Age,sex,affected side,tinnitus,and vertiginous symptom status,number of days between symptom onset and hospital admission,pure tone audiometry results at admission and after treatment were included in the study.Data were compared statistically.Results:The D allele of ACE insertion/deletion GP was significantly more frequent in patients with ISSNHL than in the control group(p=0.032).II genotype was associated with a reduced risk of ISSNHL(p=0.036).The amount of hearing loss was significantly higher in patients with the TT genotype(p=0.027)and T allele of the IL-10 GP(p=0.035)than in the patients without this allele.Severe hearing loss was a poor prognostic factor(p=0.008).Conclusions:The D allele of ACE insertion/deletion GP may be involved in the ISSNHL etiology.Due to the association of this allele with occlusive vascular pathologies,ischemia is believed to be a common pathway in the etiopathogenesis of ISSNHL. 展开更多
关键词 alpha adducin Idiopathic sudden sensorineural hearing loss Angiotensin converting enzyme Gene polymorphism INTERLEUKIN-10
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Recurrence and influencing factors of hepatitis B surface antigen seroclearance induced by peginterferon alpha-based regimens
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作者 Rui Lu Meng Zhang +13 位作者 Zi-Han Liu Miao Hao Yan Tian Mei Li Feng-Ping Wu Wen-Jun Wang Juan-Juan Shi Xin Zhang Xiao-Li Jia Zi-Cheng Jiang Xue-Mei Li Guang-Hua Xu Ya-Ping Li Shuang-Suo Dang 《World Journal of Gastroenterology》 SCIE CAS 2024年第44期4725-4737,共13页
BACKGROUND The long-term stability of hepatitis B surface antigen(HBsAg)seroclearance following peginterferon alpha(peg-IFN-α)-based therapy has not been extensively studied,leaving the full potential and limitations... BACKGROUND The long-term stability of hepatitis B surface antigen(HBsAg)seroclearance following peginterferon alpha(peg-IFN-α)-based therapy has not been extensively studied,leaving the full potential and limitations of this strategy unclear.AIM To assess HBsAg recurrence after seroclearance achieved by peg-IFN-αregimens.METHODS This prospective,multicenter,observational study was conducted from November 2015 to June 2021 at three Chinese hospitals:The Second Affiliated Hospital of Xi’an Jiaotong University,Ankang Central Hospital,and The Affiliated Hospital of Yan’an University.Participants who achieved HBsAg seroclearance following peg-IFN-α-based treatments were monitored every 4-12 weeks post-treatment for hepatitis B virus(HBV)markers,HBV DNA,and liver function.The primary outcome was HBV recurrence,defined as the reemergence of HBsAg,HBV DNA,or both,at least twice within 4-8 weeks of follow-up.RESULTS In total,121 patients who achieved HBsAg seroclearance were enrolled.After a median follow-up of 84.0(48.0,132.0)weeks,four subjects were lost to follow-up.HBsAg recurrence was detected in 16 patients.The cumulative HBsAg recurrence rate in the intention-to-treat population was 15.2%.Multivariate logistic regression analysis demonstrated that consolidation time<12 weeks[odds ratio(OR)=28.044,95%CI:4.525-173.791]and hepatitis B surface antibody disappearance during follow-up(OR=46.445,95%CI:2.571-838.957)were strong predictors of HBsAg recurrence.HBV DNA positivity and decompensation of liver cirrhosis and hepatocellular carcinoma were not observed.CONCLUSION HBsAg seroclearance following peg-IFN-αtreatment was durable over 84 weeks of follow-up with a cumulative recurrence rate of 15.2%. 展开更多
关键词 Chronic hepatitis B Peginterferon alpha Hepatitis B surface antigen seroclearance Hepatitis B surface antigen recurrence Clinical cure
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一种alpha噪声背景下的波达方向估计算法
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作者 胡喆 沈凡 殷友廷 《雷达与对抗》 2024年第3期20-24,共5页
针对在alpha噪声干扰背景下传统DOA估计算法大多性能不佳的问题,提出一种基于相关熵的降维MUSIC估计算法。首先基于阵列信号模型和alpha噪声特性分析alpha噪声背景下的信号接收模型,然后引入相关熵算子并与降维MUSIC算法相结合,最后使用... 针对在alpha噪声干扰背景下传统DOA估计算法大多性能不佳的问题,提出一种基于相关熵的降维MUSIC估计算法。首先基于阵列信号模型和alpha噪声特性分析alpha噪声背景下的信号接收模型,然后引入相关熵算子并与降维MUSIC算法相结合,最后使用Matlab对所提算法进行仿真,仿真结果证明了所提算法的有效性。该算法提升了alpha噪声干扰下的目标参数估计精度,在雷达目标探测领域有一定的工程应用价值。 展开更多
关键词 alpha噪声 DOA 相关熵准则 阵列信号处理
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Hypoxia-inducible factor 1alpha and vascular endothelial growth factor in Glioblastoma Multiforme:a systematic review going beyond pathologic implications
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作者 DIMITRA P.VAGELI PANAGIOTIS G.DOUKAS +5 位作者 KERASIA GOUPOU ANTONIOS D.BENOS KYRIAKI ASTARA KONSTANTINA ZACHAROULI SOTIRIS SOTIRIOU MARIA IOANNOU 《Oncology Research》 SCIE 2024年第8期1239-1256,共18页
Glioblastoma multiforme(GBM)is an aggressive primary brain tumor characterized by extensive heterogeneity and vascular proliferation.Hypoxic conditions in the tissue microenvironment are considered a pivotal player le... Glioblastoma multiforme(GBM)is an aggressive primary brain tumor characterized by extensive heterogeneity and vascular proliferation.Hypoxic conditions in the tissue microenvironment are considered a pivotal player leading tumor progression.Specifically,hypoxia is known to activate inducible factors,such as hypoxia-inducible factor 1alpha(HIF-1α),which in turn can stimulate tumor neo-angiogenesis through activation of various downward mediators,such as the vascular endothelial growth factor(VEGF).Here,we aimed to explore the role of HIF-1α/VEGF immunophenotypes alone and in combination with other prognostic markers or clinical and image analysis data,as potential biomarkers of GBM prognosis and treatment efficacy.We performed a systematic review(Medline/Embase,and Pubmed database search was completed by 16th of April 2024 by two independent teams;PRISMA 2020).We evaluated methods of immunoassays,cell viability,or animal or patient survival methods of the retrieved studies to assess unbiased data.We used inclusion criteria,such as the evaluation of GBM prognosis based on HIF-1α/VEGF expression,other biomarkers or clinical and imaging manifestations in GBM related to HIF-1α/VEGF expression,application of immunoassays for protein expression,and evaluation of the effectiveness of GBM therapeutic strategies based on HIF-1α/VEGF expression.We used exclusion criteria,such as data not reporting both HIF-1αand VEGF or prognosis.We included 50 studies investigating in total 1319 GBM human specimens,18 different cell lines or GBM-derived stem cells,and 6 different animal models,to identify the association of HIF-1α/VEGF immunophenotypes,and with other prognostic factors,clinical and macroscopic data in GBM prognosis and therapeutic approaches.We found that increased HIF-1α/VEGF expression in GBM correlates with oncogenic factors,such as miR-210-3p,Oct4,AKT,COX-2,PDGF-C,PLDO3,M2 polarization,or ALK,leading to unfavorable survival.Reduced HIF-1α/VEGF expression correlates with FIH-1,ADNP,or STAT1 upregulation,as well as with clinical manifestations,like epileptogenicity,and a favorable prognosis of GBM.Based on our data,HIF-1αor VEGF immunophenotypes may be a useful tool to clarify MRI-PET imaging data distinguishing between GBM tumor progression and pseudoprogression.Finally,HIF-1α/VEGF immunophenotypes can reflect GBM treatment efficacy,including combined first-line treatment with histone deacetylase inhibitors,thimerosal,or an active metabolite of irinotecan,as well as STAT3 inhibitors alone,and resulting in a favorable tumor prognosis and patient survival.These data were supported by a combination of variable methods used to evaluate HIF-1α/VEGF immunophenotypes.Data limitations may include the use of less sensitive detection methods in some cases.Overall,our data support HIF-1α/VEGF’s role as biomarkers of GBM prognosis and treatment efficacy. 展开更多
关键词 Glioblastoma multiforme(GBM) Astrocytoma Grade III Astrocytoma Grade IV Hypoxia-inducible factor 1alpha(HIF-1α) Vascular endothelial growth factor(VEGF)
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AlphaFold 3将助力药物研发
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作者 吴玉(编译) 《自然杂志》 CAS 2024年第3期184-184,共1页
2024年5月8日出版的《自然》报道了AlphaFold 3能以较高准确率预测蛋白质与其他生物分子相互作用的结构。AlphaFold 3是该人工智能模型的最新迭代,准确率与之前的专用工具相比显著提升,该模型由谷歌DeepMind和Isomorphic实验室的团队研... 2024年5月8日出版的《自然》报道了AlphaFold 3能以较高准确率预测蛋白质与其他生物分子相互作用的结构。AlphaFold 3是该人工智能模型的最新迭代,准确率与之前的专用工具相比显著提升,该模型由谷歌DeepMind和Isomorphic实验室的团队研发。这一最新模型能够预测蛋白质数据库(Protein Data Bank)内几乎所有分子类型复合物的结构。 展开更多
关键词 生物分子相互作用 谷歌 蛋白质数据库 专用工具 alpha 药物研发 人工智能模型 实验室
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