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1.
von Willebrand factor (VWF) plays a crucial role in hemostasis and thrombosis. VWF is involved in platelet attachment to the subendothelium, serving as a carrier protein for coagulation factor VIII. In this study, myocardial tissues from deceased patients with ischemic heart disease and a mouse model of acute myocardial infarction were subjected to immunohistochemistry to determine VWF expression. We examined 28 neutral formalin-fixed, paraffin-embedded myocardial tissue samples obtained from the autopsies of patients who were diagnosed with ischemic heart disease within 48 h postmortem. Most myocardial cells were negative for VWF, although some cells showed nonspecific positivity. Elevated VWF expression was observed around myocardial cells undergoing remodeling, suggesting that endothelial proliferation occurred at these sites. In contrast, completely fibrotic myocardial foci did not show upregulated VWF expression. Positivity in fibrin deposition and hemorrhagic sites was observed. The same VWF expression characteristics as those observed in the human samples were observed in the mouse model. VWF immunostaining as an endothelial marker may be a useful supplementation to conventional staining techniques that are currently used in the diagnosis of ischemic heart disease in terms of examining the timing of myocardial remodeling in detail and highlighting the remodeling process. 相似文献
2.
《Saudi Pharmaceutical Journal》2022,30(5):595-604
Anthrax is a zoonotic infection caused by the gram-positive, aerobic, spore-forming bacterium Bacillus anthracis. Depending on the origin of the infection, serious health problems or mortality is possible. The virulence of B. anthracis is reliant on three pathogenic factors, which are secreted upon infection: protective antigen (PA), lethal factor (LF), and edema factor (EF). Systemic illness results from LF and EF entering cells through the formation of a complex with the heptameric form of PA, bound to the membrane of infected cells through its receptor. The currently available anthrax vaccines have multiple drawbacks, and recombinant PA is considered a promising second-generation vaccine candidate. However, the inherent chemical instability of PA through Asn deamidation at multiple sites prevents its use after long-term storage owing to loss of potency. Moreover, there is a distinct possibility of B. anthracis being used as a bioweapon; thus, the developed vaccine should remain efficacious and stable over the long-term. Second-generation anthrax vaccines with appropriate adjuvant formulations for enhanced immunogenicity and safety are desired. In this article, using protein engineering approaches, we have reviewed the stabilization of anthrax vaccine candidates that are currently licensed or under preclinical and clinical trials. We have also proposed a formulation to enhance recombinant PA vaccine potency via adjuvant formulation. 相似文献
3.
摘要:目的以分子测序为参考 ,评估形态学、基质辅助激光解吸电离飞行时间质谱对毛霉目真菌的鉴定能力,分析毛霉目真菌对两性霉素B、泊沙康唑的体外药敏特点。方法收集 2018年1月-2022年2月广东省人民医院25例毛霉病住院患者标
本,进行镜检并对培养的茵落行形态学鉴定、质谱鉴定、分子测序和体外药敏试验。结果KOH 湿片法阳性率(76%)高于革兰染色法(32%),差异有统计学意义(P<0.05);形态学鉴定可将68%的菌株鉴定到属水平,3株鉴定错误,2株无法鉴定;将所
有菌株进行质谱鉴定,单用IVD和RUO数据库鉴定率分别为56%和44%,两库联合可将鉴定率提高为64%。毛霉目真菌对两性霉素B的抑制50%菌株生长的最小抑菌浓度(MIC3o)为1μg/mL,根霉属相比其他属对两性霉素B表现出较高的MIC
值,其中2株MIC>32 μg/mL,另2株MIC为8 μg/mL;根霉属对泊沙康唑的MICso为0.5 μg/mL,横梗霉属MICgo为4 μg/ mL,小克银汉霉属MICg0为2 μg/mL,有部分菌株表现出较低MIC值,同样亦有部分菌株对泊沙康唑表现出较高的MIC 值。结论
将传统镜检、培养与质谱技术和分子技术相结合,尽量将毛霉目真菌准确鉴定到种,并积极开展毛霉体外药敏试验,可为临床治疗提供参考依据。 相似文献
4.
《Revista brasileira de otorrinolaringologia (English ed.)》2022,88(4):621-624
ObjectivesRecurrent Aphthous Stomatitis (RAS) a chronic idiopathic oral mucosal disease. But yet the etiology and pathogenesis of RAS are not exactly known, it is thought that inflammation play an important role in the pathogenesis. The aim of this study is to demonstrate the role of systemic inflammation among the possible etiological factors of RAS and to find the possible diagnostic correlation between Systemic Immune Inflammation Index (SII).MethodsPatients who were consulted the otolaryngology outpatient clinic and diagnosed with RAS between 2019–2021 were retrospectively analyzed. Neutrophil/Lymphocyte Ratio (NLR), Platelet/Lymphocyte Ratio (PLR) and SII values were calculated based on the results of complete blood count. Demographic and hematological parameters between control and RAS groups were compared. The statistical significance level was considered as <0.05.ResultsThere was no statistically significant difference between the control and RAS groups in terms of sex and age distributions (p = 0.566 and p = 0.173, respectively). SII, NLR and PLR values were significantly higher in the RAS group compared to the controls (p < 0.001, p < 0.001 and p = 0.001, respectively). A very strong correlation between SII and NLR, moderately strong correlation between SII and PLR and moderate correlation between NLR and PLR values were detected (respectively ρ: 0.813, 0.719, 0.532; p-values <0.001).ConclusionSII, NLR and PLR has significantly higher levels in the RAS group compared to the control group, that it supports the role of systemic inflammation in the etiopathogenesis of RAS. In addition, the results show that SII is a valuable marker for inflammation.Level of evidence4. 相似文献
5.
目的 通过网络药理学及分子对接技术探寻复方一枝蒿颗粒治疗新型冠状病毒肺炎的作用机制。方法 应用TCMSP数据库、BATMAN-TCM数据库及文献收集复方一枝蒿颗粒活性成分及潜在靶点。通过TTD、GeneCards和OMMI数据库检索新型冠状病毒肺炎相关的靶点。将复方一枝蒿颗粒药物靶点和新型冠状病毒肺炎相关基因取交集,使用String数据库构建靶蛋白相互作用(PPI)网络。通过Cytoscape构建“药物–活性成分–靶点基因–疾病”网络。对交集靶点进行GO功能、KEGG通路富集分析。利用Autodock_vina软件对活性成分和靶点进行分子对接。结果 共筛选92个活性成分,1 627个靶点,新型冠状病毒肺炎疾病靶点464个,两者取交集筛选出87个潜在靶点。GO功能富集得到2 040个条目(P<0.05),与病毒过程、参与共生相互作用的生物过程、活性氧代谢过程的调节、与宿主相互作用的生物过程、病毒生命周期、炎症反应的调节等生物学过程有关。KEGG通路分析共得到150条通路,与新冠肺炎密切相关的有人巨细胞病毒感染、结核、COVID-19、IL-17信号通路等。分子对接结果证实,筛选的靶点受体蛋白与活性成分可以较好地结合。结论 复方一枝蒿颗粒可通过多组分、多靶点和多途径的方式对新型冠状病毒肺炎产生治疗作用。 相似文献
6.
一测多评法(quantitative analysis of multi-components by single marker,QAMS)已成熟应用于中药材、中药提取物及中成药领域等中药复杂体系的质量评价研究中,有效解决了因对照品缺乏而导致的多指标质控技术推广难问题。本文查阅近五年的国内外研究文献,重点总结了高效液相色谱、气相色谱和质谱等技术在QAMS法中药质量控制中的应用。高效液相色谱联用紫外检测器(UV)技术应用最为广泛,最适合于中药QAMS法定量,结果稳定、准确;而高效液相色谱联用蒸发光检测器在中药QAMS法应用中,其测定准确性和适用性仍然需进一步探索和验证。液质联用技术虽然具有灵敏度高、线性范围宽等优点,但易受仪器参数、基质效应等的影响。进一步发展HPLC-UV技术在中成药制剂质量评价中的应用,是QAMS法多成分定量值得关注的方向;探索LC-MS和GC技术在中药QAMS质量评价中的稳定性和普适性是未来将面临的挑战。 相似文献
7.
目的探讨低分子量肝素在子痫前期患者中的应用效果。方法回顾性调查我院2019年1~4月290例子痫前期患者,根据产后1 d采用的治疗方法分为肝素组(190例)及对照组(100例),分析比较两组的一般资料和凝血指标差异。结果肝素组的新生儿体重和Apgar评分(1 min)低于对照组(P<0.05)。肝素组与对照组在产前仅凝血酶时间、D-二聚体、血小板体积分布宽度有差异,产后1 d肝素组纤维蛋白原含量、血小板计数、血小板压积低于对照组,凝血酶时间、D-二聚体、血小板体积分布宽度高于对照组(P<0.05)。产后3 d仅D-二聚体有差异。结论在产后1 d应用低分子量肝素有助于子痫前期患者产后凝血状态向正常恢复。 相似文献
8.
目的探讨血浆硫氧还蛋白还原酶(TR)在肺癌化疗疗效监测中的价值。方法将482例肺癌患者依据化疗疗效分为治疗未获益组(211例)和治疗获益组(271例),检测所有患者TR、癌胚抗原(CEA)、鳞状上皮细胞癌抗原(SCC-Ag)、细胞角蛋白19片段(CYFRA 21-1)、神经元特异性烯醇化酶(NSE)及胃泌素释放肽前体(ProGRP)水平。采用受试者工作特征(ROC)曲线评估各项指标单项及联合检测判断化疗疗效的价值。结果治疗未获益组TR、CEA及NSE水平均高于治疗获益组(P<0.05),2个组之间SCC-Ag、CYFRA21-1及ProGRP水平差异均无统计学意义(P>0.05)。治疗未获益组TR阳性率为56.40%,显著高于治疗获益组(13.16%)(P<0.05)。ROC曲线分析结果显示,TR、CEA、CYFRA 21-1、SCCAg、NSE及ProGRP单项检测判断肺癌化疗疗效的曲线下面积(AUC)分别为0.759、0.667、0.579、0.530、0.619、0.544。将各项指标进行组合,TR+CEA、TR+CEA+CYFRA21-1、TR+CEA+CYFRA21-1+NSE及TR+CEA+CYFRA 21-1+NSE+ProGRP联合检测判断肺癌化疗疗效的AUC分别为0.757、0.749、0.752和0.788。TR与CEA、NSE、SCC-Ag、CYFRA 21-1及ProGRP均无相关性(r值分别为0.05、0.02、-0.15、0.05、0.10,P>0.05)。结论TR或可作为更有效的肺癌疗效监测的生物标志物。 相似文献
9.
The advent of nanotechnology has revolutionized the way clinicians are treating cancers. Treatment for cancer includes surgery, radiotherapy, hormonal therapy, chemotherapy, and now nano therapy, which could be a possible alternative. This new treatment regime can be beneficial since it shows minimum side effects as compared to other treatment methods. Metallic nanoparticles synthesized through green chemistry by using biological entities minimizes the side effects and enhances the properties of the metal against cancer cells. These green nanoparticles are widely used in research and have shown promising cytotoxic activity against various cancer cell lines. Mechanistically, these nanoparticles can enter the cancer cell and cause cell death by the activation of various molecular pathways such as apoptosis, necrosis and autophagy. This review focuses on the metal nanoparticles (silver, gold and copper) synthesized by the green chemistry approach that have been utilized to study the cancer cell death and we are also discussing the underlying molecular pathways. 相似文献
10.
目的:探讨补肾活血汤治疗激素性股骨头坏死(steroid-induced osteonecrosis of the femoral head,SONFH)的作用机制。方法:通过中医药整合药理学网络计算研究平台(integrative pharmacology-based network computational research platform of Traditional Chinese Medicine,TCMIP)v2.0预测、筛选补肾活血汤组方中14味中药的作用靶标,通过GeneCards、CTD和OMIM数据库查询SONFH的疾病靶点。根据获取的药物靶标和疾病靶点,进一步利用TCMIP v2.0中医药关联网络分析模块构建"药物靶标-疾病靶点"相互作用网络,根据网络拓扑特征值筛选补肾活血汤治疗SONFH的核心作用靶点。利用GO和KEGG数据库,采用富集算法挖掘上述方剂核心作用靶点的生物学功能和通路信息。结果:共获得891个补肾活血汤药物靶标和365个SONFH疾病靶点。经"药物靶标-疾病靶点"相互作用网络分析,最终筛选出31个补肾活血汤治疗SONFH核心靶点,GO功能分析富集出生物过程532条、分子功能29条,KEGG信号通路富集分析出相关通路共12条,主要涉及炎症免疫调节(chemokine signaling pathway,Toll-like receptor signaling pathway,NOD-like receptor signaling pathway,leukocyte transendothelial migration,Complement and coagulation cascades,cytokine-cytokine receptor interaction)、血管新生及血液循环调节(VEGF signaling pathway)、神经系统调节(neuroactive ligand-receptor interaction)和细胞功能调节(apoptosis,regulation of actin cytoskeleton)等方面。结论:结合SONFH的病理机制,排除缺乏特异性的信号通路,我们推测补肾活血汤可能通过调节TLR4/NF-κB和VEGF信号通路发挥补肾壮骨、活血化瘀的功效,这可能是其治疗SONFH的作用机制之一。 相似文献