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81.
In the 35 years since the revelation that short peptides bound to major histocompatibility complex class I and II molecules are the secret of the major histocompatibility complex–restricted nature of T-cell recognition, there has been enormous progress in characterizing the immunopeptidome, the repertoire of peptide presented for immunosurveillance. Here, the major milestones in the journey are marked, the contribution of proteasome-mediated splicing to the immunopeptidome is discussed, and exciting recent findings relating the immunopeptidome to the translatome revealed by ribosome profiling (RiboSeq) is detailed. Finally, what is needed for continued progress is opined about, which includes the infusion of talented young scientists into the antigen-processing field, currently undergoing a renaissance; thanks in part to the astounding success of T-cell–based cancer immunotherapy.  相似文献   
82.
ObjectiveInfluenza A virus belongs to the most studied virus and its mutant initiates epidemic and pandemics outbreaks. Inoculation is the significant foundation to diminish the risk of infection. To prevent an incidence of influenza from the transmission, various practical approaches require more advancement and progress. More efforts and research must take in front to enhance vaccine efficacy.MethodsThe present research emphasizes the development and expansion of a universal vaccine for the influenza virus. Research focuses on vaccine design with high efficacy. In this study, numerous computational approaches were used, covering a wide range of elements and ideas in bioinformatics methodology. Various B and T-cell epitopic peptides derived from the Neuraminidase protein N1 are recognized by these approaches. With the implementation of numerous obtained databases and bioinformatics tools, the different immune framework methods of the conserved sequences of N1 neuraminidase were analyzed. NCBI databases were employed to retrieve amino acid sequences. The antigenic nature of the neuraminidase sequence was achieved by the VaxiJen server and Kolaskar and Tongaonkar method. After screening of various B and T cell epitopes, one efficient peptide each from B cell epitope and T cell epitopes was assessed for their antigenic determinant vaccine efficacy. Identical two B cell epitopes were recognized from the N1 protein when analyzed using B-cell epitope prediction servers. The detailed examination of amino acid sequences for interpretation of B and T cell epitopes was achieved with the help of the ABCPred and Immune Epitope Database.ResultsComputational immunology via immunoinformatic study exhibited RPNDKTG as having its high conservancy efficiency and demonstrated as a good antigenic, accessible surface hydrophilic B-cell epitope. Among T cell epitope analysis, YVNISNTNF was selected for being a conserved epitope. T cell epitope was also analyzed for its allergenicity and cytotoxicity evaluation. YVNISNTNF epitope was found to be a non-allergen and not toxic for cells as well. This T-cell epitope with maximum world populace coverages was scrutinized for its association with the HLA-DRB1*0401 molecule. Results from docking simulation analyses showed YVNISNTNF having lower binding energy, the radius of gyration (Rg), RMSD values, and RMSE values which make the protein structure more stable and increase its ability to become an epitopic peptide for influenza virus vaccination.ConclusionsWe propose that this epitope analysis may be successfully used as a measurement tool for the robustness of an antigen–antibody reaction between mutant strains in the annual design of the influenza vaccine.  相似文献   
83.
目的:探讨组织冻结融化造成血管内皮细胞(VEC)损伤的机理。方法:采用密度梯度离心法分离大鼠外周血嗜中性粒细胞(PMN),速率冷冻仪冷冻PMN后水浴复温建立冻融PMN模型。冻融后4、12和24h,测定PMN表面淋巴细胞功能相关抗原-1(LFA-1)的表达;将冻融PMN与正常VEC共同孵育后测定培养液中乳酸脱氢酶活性及冻融PMN与VEC的粘附。结果:冻融后24h内,冻融PMN表面LFA-1的表面呈时间依赖性增强。(2)冻融PMN与VEC相互作用后,PMN-VEC粘附明显增强、VEC受到明显损伤。(3)抗LFA-1单克隆抗体明显抑制冻融PMN与VEC粘附的增强、明显减轻VEC损伤。结论:冻融可诱发PMN表面LFA-1的表达,进而增强PMN-VEC粘附而导致VEC损伤。  相似文献   
84.
目的了解住院腹泻患者艰难梭菌及其毒素A/B的检出情况,为临床诊断抗生素相关性腹泻提供参考依据。方法收集2015年9月至2016年8月崇州市人民医院疑似抗生素相关性腹泻住院患者的粪便标本163份,用艰难梭菌快速检测试剂盒检测艰难梭菌特异性抗原谷氨酸脱氢酶(GDH);用酶联免疫荧光法检测GDH阳性标本中艰难梭菌毒素A/B的产生情况。结果 163份粪便标本中GDH阳性为34份,阳性率为20.86%。34份GDH阳性标本中艰难梭菌毒素A/B阳性率为41.18%(14/34),可疑阳性率为17.65%(6/34),阴性率为41.18%(14/34)。结论疑似抗生素相关性腹泻住院患者艰难梭菌GDH检出率较高,毒素A/B阳性率也比较高,提示临床应重视抗生素相关性腹泻患者艰难梭菌感染的诊断。  相似文献   
85.
We reported comprehensive screening for antigens (Ags) overexpressed on various carcinomas via isolation of human monoclonal antibodies (mAbs) that may be therapeutic in a previous paper (Proc. Natl. Acad. Sci. USA 105, 7287-7292, 2008). Twenty-one distinct Ags highly expressed on several carcinomas were identified and 356 mAbs with unique sequences turned out to bind to one of the 21 Ags. Among them CADM1/IGSF4 which had been originally referred to as tumor suppressor lung cancer 1 (TSLC1) was included. Therefore we examined the expression of CADM1 in lung cancers in this study. Eight different anti CADM1 mAbs were used for immunohistochemical analysis of 29 fresh lung cancer specimens. Staining patterns were categorized to six groups based on the extent of positive staining and the localization of stained portions. While overexpression of CADM1 was observed on the cell surface of adenocarcinomas at a high frequency, around 60%, positive stainings were rarely observed on that of other lung carcinomas including squamous cell carcinomas. Moreover, some clones among the eight mAbs gave different staining patterns from those by the other clones against the same fresh specimen, suggesting presence of variant forms of CADM1 differentiated by mAbs.  相似文献   
86.
Human saliva, which contains nitrite, is normally mixed with gastric juice, which contains ascorbic acid (AA). When saliva was mixed with an acidic buffer in the presence of 0.1 mM AA, rapid nitric oxide formation and oxygen uptake were observed. The oxygen uptake was due to the oxidation of nitric oxide, which was formed by AA-dependent reduction of nitrite under acidic conditions, by molecular oxygen. A salivary component SCN enhanced the nitric oxide formation and oxygen uptake by the AA/nitrite system. The oxygen uptake by the AA/nitrite/SCN system was also observed in an acidic buffer solution. These results suggest that oxygen is normally taken up in the stomach when saliva and gastric juice are mixed.  相似文献   
87.
摘要 目的:探讨帕瑞昔布钠和右美托咪定联合麻醉对老年腹腔镜胃癌手术患者细胞免疫功能、应激反应和认知功能的影响。方法:纳入2019年8月~2022年7月期间西安交通大学第二附属医院收治的150例老年腹腔镜胃癌手术患者。按照随机数字表法将患者分为帕瑞昔布钠组(n=50,帕瑞昔布钠)、右美托咪定组(n=50,右美托咪定)和联合组(n=50,右美托咪定联合帕瑞昔布钠)。对比三组临床指标、视觉模拟评分法(VAS)、简易精神状态检查表(MMSE)评分、术后认知功能障碍(POCD)发生率、应激反应指标[皮质醇(Cor)、肾上腺素(E)、促肾上腺皮质激素(ACTH)]、细胞免疫功能变化情况。结果:联合组的术后住院天数、肛门排气时间短于右美托咪定组、帕瑞昔布钠组(P<0.05)。联合组术后12 h、术后24 h、术后48 h VAS评分低于右美托咪定组、帕瑞昔布钠组(P<0.05)。联合组术后24 h、术后72 h MMSE评分高于右美托咪定组、帕瑞昔布钠组(P<0.05)。联合组的POCD发生率低于右美托咪定组、帕瑞昔布钠组(P<0.05)。三组术后1 d Cor、E、ACTH升高,但联合组低于帕瑞昔布钠组、右美托咪定组同期(P<0.05)。三组术后1 d CD8+升高,但联合组低于帕瑞昔布钠组、右美托咪定组同期;CD3+、CD4+、CD4+CD8+下降,但联合组高于帕瑞昔布钠组、右美托咪定组同期(P<0.05)。结论:右美托咪定联合帕瑞昔布钠应用于老年腹腔镜胃癌手术患者,镇痛效果显著,可减轻机体的应激反应、免疫抑制及对认知功能的损害。  相似文献   
88.
摘要 目的:分析血管生成素样蛋白4(ANGPTL4)和Ⅱ型肺泡细胞表面抗原-6(KL-6)与急性呼吸窘迫综合征严重程度的关系及对预后的评估效能。方法:选择我院自2020年1月至2022年12月收治的120例急性呼吸窘迫综合征患者作为研究对象(观察组),根据氧合指数(PaO2/FiO2)分为轻度组、中度组和重度组;另选120例非急性呼吸窘迫综合征患者作为对照组。检测所有患者血清ANGPTL4和KL-6的表达水平,分析血清ANGPTL4和KL-6与APACHE Ⅱ评分、PaO2/FiO2的关系,使用受试者工作特征曲线(ROC)下面积(AUC)评价血清ANGPTL4联合KL-6对急性呼吸窘迫综合征预后的评估效能。结果:对比对照组,观察组血清ANGPTL4、KL-6的表达水平均明显升高(P<0.05);血清ANGPTL4、KL-6的表达水平在轻度组、中度组和重度组中差异有统计学意义,且急性呼吸窘迫综合征越严重,升高越明显(P<0.05);经Pearson相关性分析,急性呼吸窘迫综合征患者血清ANGPTL4、KL-6的表达水平与PaO2/FiO2呈负相关,与APACHE Ⅱ评分呈正相关(P<0.05);经ROC曲线分析,血清ANGPTL4联合KL-6预测急性呼吸窘迫综合征患者入院28d内死亡的敏感度为90.14%、特异度为65.74%,AUC为0.900。结论:血清ANGPTL4、KL-6表达水平升高与急性呼吸窘迫综合征严重程度增大密切相关,两者联合在患者预后评估中具有一定价值,可作为判断病情及预后的辅助指标。  相似文献   
89.
摘要 目的:探讨细胞角蛋白19片段(CYFRA21-1)、基质金属蛋白酶-3(MMP-3)及癌胚抗原(CEA) 和细胞学联合检查对恶性胸腔积液的诊断价值。方法:选择2020年1月至2023年1月我院接诊的100例胸腔积液患者进行研究,并根据病理结果分为实验组47例(病理检查结果恶性),对照组53例(病理检查结果良性),分析血清CYFRA21-1、MMP-3及CEA 和细胞学水平变化情况及其的诊断价值。结果:实验组患者血清血清CYFRA21-1、MMP-3及CEA水平显著高于对照组,差异显著(P<0.05);实验组患者CYFRA21-1、MMP-3及CEA 和细胞学阳性率均显著高于对照组,差异显著(P<0.05);CYFRA21-1诊断恶性胸腔积液的AUC为0.989,95%CI为0.977~1.000;MMP-3诊断恶性胸腔积液的AUC为0.979,95%CI为0.964~0.994;CEA 诊断恶性胸腔积液的AUC为0.982,95%CI为0.967~0.997;细胞学诊断恶性胸腔积液的AUC为0.823,95%CI为0.766~0.879,联合检测时AUC为0.995,95%CI为0.990~1.000,较单独检测曲线下面积比较显著差异;且特异度、准确度均较单独检测更高。结论:CYFRA21-1、MMP-3及CEA 和细胞学联合检查可有效提高诊断恶性胸腔积液的准确性,临床应用价值高。  相似文献   
90.
Abstract An isoprotein of enolase from the yeast Saccharomyces cerevisiae was reported to be a heat shock protein. The possible role of the C. albicans enolase as a heat shock protein was therefore investigated. The de novo synthesis of C. albicans enolase protein and mRNA did not increase during heat stress, but remained constitutively expressed. Amino acid similarity to the heat shock proteins suggests that although the C. albicans enolase is not a classical heat shock protein, it may be a memberof a group of constitutively expressed, structurally related proteins, the heat shock cognate proteins.  相似文献   
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