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991.
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Zhi-Xue Zheng 《World Journal of Clinical Cases》2021,9(36):11148-11155
Novel coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global pandemic. SARS-CoV-2 is an RNA virus and has a glycosylated spike (S) protein used for genome encoding. COVID-19 can lead to a cytokine storm and patients usually have early respiratory signs and further secondary infections, which can be fatal. COVID-19 has entered an emergency phase, but there are still no specific effective drugs for this disease. Mesenchymal stem cells (MSCs) are multipotent stromal cells, which cause antiapoptosis and can repair damaged epithelial cells. Many clinical trials have proved that MSC therapy could be a potential feasible therapy for COVID-19 patients, especially those with acute respiratory distress syndrome, without serious adverse events or toxicities. However, more studies are needed in the future, in order to confirm the effect of this therapy. 相似文献
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目的 基于网络药理学研究香菇多糖抑制三阴乳腺癌(TNBC)的作用机制并采用细胞和动物实验进行验证。方法 通过GeneCards数据库和DisGeNET数据库筛选与TNBC相关基因靶点,利用TCMID、PubChem、SwissTargetPrediction和GeneCards数据库查询香菇多糖相关基因靶点。使用Sangerbox软件进行基因本体论(GO)富集和京都基因与基因组百科全书(KEGG)通路富集分析。结合STRING数据库与Cytoscape 3.7.0软件将共同靶点进行可视化处理,筛选核心靶点,构建"化合物-靶点-通路"网络。利用Metascape软件进行转录因子及相关调控基因特异富集。体外培养小鼠TNBC细胞4T1和人TNBC细胞MDA-MB-231,磺酰罗丹明B染色法观察香菇多糖(31.25、62.5、125、250、500、1 000μg·mL-1)对细胞存活率的影响;健康雌性BABLC小鼠sc接种1×106个4T1-Luc细胞构建TNBC模型,通过小动物活体成像系统观察香菇多糖(100、200 mg·kg-1)对肿瘤生长的影响,实时荧光定量PCR (qRT-PCR)技术检测肿瘤组织信号转导和转录活化因子3(STAT3)和血管内皮生长因子A (VEGFA) mRNA表达。结果 数据库及软件分析得到香菇多糖治疗TNBC关键靶点52个,靶点主要涉及PI3K-Akt、AGE-RAGE、HIF-1、MAPK信号通路和肿瘤蛋白多糖相关通路,PPI分析得到VEGFA、STAT3、MAPK1、IL2、TNF、RELA、AKT1、MAPK3、BCL2L1和HSP90AA1 10个hub基因。与对照组比较,香菇多糖对4T1和MDA-MB-231细胞存活率均有显著抑制作用(P<0.05、0.01),且作用呈浓度相关性;在给药14、21d后,与模型组比较,香菇多糖能够剂量相关性地抑制小鼠TNBC肿瘤的生长,高剂量组差异显著(P<0.05、0.01),21 d抑制率达到(91.9±4.7)%;与对照组比较,香菇多糖给药后能够剂量相关性抑制STAT3和VEGFA的mRNA表达,高剂量组差异显著(P<0.05、0.01)。结论 香菇多糖可通过多靶点、多途径协同作用抑制TNBC的生长。 相似文献
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《Allergology international》2022,71(3):278-287
The nervous system and the immune system individually play important roles in regulating the processes necessary to maintain physiological homeostasis, respond to acute stress and protect against external threats. These two regulating systems for maintaining the living body had often been assumed to function independently. Allergies develop as a result of an overreaction of the immune system to substances that are relatively harmless to the body, such as food, pollen and dust mites. Therefore, it has been generally supposed that the development and pathogenesis of allergies can be explained through an immunological interpretation. Recently, however, neuro-immune crosstalk has attracted increasing attention. Consequently, it is becoming clear that there is close morphological proximity and physiological and pathophysiological interactions between neurons and immune cells in various peripheral tissues. Thus, researchers are now beginning to appreciate that neuro-immune interactions may play a role in tissue homeostasis and the pathophysiology of immune-mediated disease, but very little information is available on the molecular basis of these interactions. Mast cells are a part of the innate immune system implicated in allergic reactions and the regulation of host–pathogen interactions. Mast cells are ubiquitous in the body, and these cells are often found in close proximity to nerve fibers in various tissues, including the lamina propria of the intestine. Mast cells and neurons are thought to communicate bidirectionally to modulate neurophysiological effects and mast cell functions, which suggests that neuro-immune interactions may be involved in the pathology of allergic diseases. 相似文献
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PurposeTo evaluate in vivo parameters as biomarkers of limbal stem cell function and to establish an objective system that detects and stage limbal stem cell deficiency (LSCD).MethodsA total of 126 patients (172 eyes) with LSCD and 67 normal subjects (99 eyes) were included in this observational cross-sectional comparative study. Slit-lamp biomicroscopy, in vivo laser scanning confocal microscopy (IVCM), and anterior segment optical coherence tomography (AS-OCT) were performed to obtain the following: clinical score, cell morphology score, basal cell density (BCD), central corneal epithelial thickness (CET), limbal epithelial thickness (LET), total corneal nerve fiber length (CNFL), corneal nerve fiber density (CNFD), corneal nerve branch density (CNBD), and tortuosity coefficient. Their potential correlations with the severity of LSCD were investigated, and cutoff values were determined.ResultsAn increase clinical score correlated with a decrease in central cornea BCD, limbal BCD, CET, mean LET, maximum LET, CNFL, CNFD, CNBD, and tortuosity coefficient. Regression analyses showed that central cornea BCD, CET and CNFL were the best parameters to differentiate LSCD from normal eyes (Coef = 3.123, 3.379, and 2.223; all p < 0.05). The rank correlation analysis showed a similar outcome between the clinical scores and the central cornea BCD (ρ = 0.79), CET (ρ = 0.82), and CNFL (ρ = 0.71). A comprehensive LSCD grading formula based on a combination of these parameters was established.ConclusionsA comprehensive staging system combining clinical presentation, central cornea BCD, CET, and CNFL is established to accurately and objectively diagnose LSCD and stage its severity. 相似文献
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肺癌是目前世界上发病率第二、死亡率第一的恶性肿瘤。非小细胞肺癌(NSCLC)是其主要病理类型,且易发生脑转移。目前,NSCLC脑转移的主要治疗方式包括手术、放疗、化疗、分子靶向治疗和免疫治疗等。放疗是脑转移局部治疗的常用方法,随着技术和药物的不断发展更新,放疗与其他治疗手段如何联合是目前临床研究热点。本文将对NSCLC脑转移放射治疗进展进行综述,从而为临床工作中治疗方案的选择提供参考。 相似文献