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11.
目的探讨支气管哮喘患儿中性粒细胞胞外诱捕网水平与患者免疫功能及临床预后的关系。方法选取本院2017年9月-2018年9月支气管哮喘患者80例作为观察组,并以同期健康体检的30例儿童作为对照组,采用pico Green dsDNA荧光染色定量检测支气管哮喘患者NETs水平,采用T淋巴细胞亚群评价患者免疫功能,对比不同NETs水平患者免疫功能及临床特点,采用Logistic回归分析探讨小儿支气管哮喘急性发作的风险因素。结果观察组白细胞、中性粒细胞、单核细胞、Cf-DNA/NETs水平均高于对照组(P <0. 05),而淋巴细胞水平低于对照组,差异均有统计学意义(P <0. 05)。Logistic回归分析显示,哮喘家族史、呼吸道感染、Cf-DNA/NETs水平上升、有害气体接触、被动吸烟均是支气管哮喘急性发作的独立危险因素(P <0. 05)。结论中性粒细胞胞外诱捕网水平与支气管哮喘患者免疫功能及预后密切相关,值得临床重点关注。 相似文献
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Chronological Changes in Neutrophil/lymphocyte Ratio in Advanced Gastric Cancer Patients Treated with Nivolumab: a Report of Nine Cases 下载免费PDF全文
Naohiko NakamuraShinichi KinamiJun FujitaDaisuke KaidaYasuto TomitaTakashi MiyataHideto FujitaHiroyuki TakamuraNobuhiko UedaTakeo Kosaka 《Asian Pacific journal of cancer prevention》2020,21(10):2955-2960
Background: Nivolumab has been approved for use in advanced gastric cancer (GC) after third-line chemotherapy in Japan. However, it remains difficult to predict favorable nivolumab response before treatment. Methods: We evaluated the clinical course with a focus on the chronological changes in neutrophil/lymphocyte ratio (NLR) throughout the chemotherapy and assessed the relationship between nivolumab response and chronological changes in NLR before nivolumab administration. Results: We experienced nine cases who received nivolumab monotherapy for unresectable advanced or postoperative recurrent GC. Nivolumab was used as third-line chemotherapy in all patients, and partial response (PR) and stable disease (SD) were observed in two patients each. Nivolumab treatment resulted in progressive disease (PD) in five patients. In patients with PR or SD, changes in the NLR tended to correspond to the response of target metastatic lymph nodes to first- and second-line chemotherapy. In the four cases with PR or SD following nivolumab, ∆NLRresponses that was the difference in the degree of decline during the most effective pretreatment chemotherapy were 1.39, 0.73, 1.62, and 1.22. However, the patients with PD showed lower ∆NLRresponses, at 0.66, 0.66, 0.25, 0.13, and -0.05 in the five cases. Mean ∆NLRresponses in the patients with PR or SD and patients with PD were 1.17 and 0.33, respectively (P = 0.0008). Conclusions: We experienced nine GC cases treated with nivolumab and assessed the association between chronological NLR changes throughout chemotherapy and tumor response to nivolumab. Changes in NLR during pretreatment chemotherapy might predict tumor response to nivolumab monotherapy in patients with advanced GC. 相似文献
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Jinlan He Jianxiong He Li Min Yan He Hui Guan Jingjing Wang Xingchen Peng 《International journal of cancer. Journal international du cancer》2020,146(4):1052-1063
Sorafenib provides survival benefits in patients with advanced renal cell carcinoma (RCC), but its use is hampered by acquired drug resistance. It is important to fully clarify the molecular mechanisms of sorafenib resistance, which can help to avoid, delay or reverse drug resistance. Extracellular vesicles (EVs) can mediate intercellular communication by delivering effector molecules between cells. Here, we studied whether EVs are involved in sorafenib resistance of RCC and its possible molecular mechanisms. Using differential centrifugation, EVs were isolated from established sorafenib-resistant RCC cells (786-0 and ACHN), and EVs derived from sorafenib-resistant cells were uptaken by sensitive parental RCC cells and thus promoted drug resistance. Elevated exogenous miR-31-5p within EVs effectively downregulated MutL homolog 1 (MLH1) expression and thus promoted sorafenib resistance in vitro. Mice experiments also confirmed that miR-31-5p could mediate drug sensitivity in vivo. In addition, low expression of MLH1 was observed in sorafenib-resistant RCC cells and upregulation of MLH1 expression restored the sensitivity of resistant cell lines to sorafenib. Finally, miR-31-5p level in circulating EVs of RCC patients with progressive disease (PD) during sorafenib therapy was higher when compared to that in the pretherapy status. In conclusion, EVs shuttled miR-31-5p can transfer resistance information from sorafenib-resistant cells to sensitive cells by directly targeting MLH1, and thus magnify the drug resistance information to the whole tumor. Furthermore, miR-31-5p and MLH1 could be promising predictive biomarkers and therapeutic targets to prevent sorafenib resistance. 相似文献
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大鼠内毒素血症时外周血及肺泡内中性粒细胞死亡方式及呼吸爆发 总被引:2,自引:0,他引:2
本研究观察大鼠内毒素血症时肺组织中及外周血多形核中性粒细胞(PMN)凋亡,坏死及功能改变的差异。采用Wistar大鼠20只。腹腔注射LPS(O55B5,5mg/kg)造成内毒素血症,给予LPS后2,4,8,12小时(每组5只动物)取血及支气管肺泡灌洗,密度梯度法分离PMN,用流式细胞仪测定凋亡和坏死比例以及呼吸爆发功能的改变,同时采用5只大鼠作为正常对照。结果显示,内毒素血症时外周血和支气管肺泡灌洗液中PMN凋亡细胞比例相似。但与对照相比,外周血PMN坏死比例明显增加,呼吸爆发能力明显受抑,而支气管肺泡灌洗液PMN坏死比例显减少,呼吸爆发能力显增强。结论:在内毒素血症时,扣押于肺组织中的PMN在凋亡和坏死上表现出与比例显减少,呼吸爆发能力显增强,结论:在内毒素血症时,扣押于肺组织中的PMN在凋亡和坏死上表现出与外周血PMN不同的改变,其结果是组织中PMN存活增加,并持续处于活化状态,这与PMN造成组织损伤有关。 相似文献
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Summary: Fifty-seven isolates of Basidiobolus from reptiles and amphibians, and 7 other obtained from the American Type Culture Collection (ATCC) in Maryland were studied for their extracellular enzyme activities on solid media. The Conidiobolus isolates studied included 4 recovered from Nigerian soil and additional 4 obtained from the ATCC All these isolates produced active extracellular lipase and protease and failed to exhibit amylase, deoxyribonuclease and ribonuclease activities. The significance of the findings is discussed.
Zusammenfassung: Fünfundsiebzig Basidiobolus-Isolate aus Reptilien und Amphibien und sieben weitere aus der American Type Culture Collection (ATCC) in Maryland wurden auf Aktivtäten extrazellulärer Enzyme auf festen Medien untersucht Die untersuchten Conidiobolus-Isolate schlossen vier aus nigerianischen Böden und vier weitere aus der ATCC ein. Alle Isolate zeigten extrazellulär Lipase- und Proteaseaktivität Amylase-, Desoxyribonuclease- und Ribonucleaseaktivität war jedoch nicht nachzuweisen. Die Bedeutung dieser Befunde wird diskutiert. 相似文献
Zusammenfassung: Fünfundsiebzig Basidiobolus-Isolate aus Reptilien und Amphibien und sieben weitere aus der American Type Culture Collection (ATCC) in Maryland wurden auf Aktivtäten extrazellulärer Enzyme auf festen Medien untersucht Die untersuchten Conidiobolus-Isolate schlossen vier aus nigerianischen Böden und vier weitere aus der ATCC ein. Alle Isolate zeigten extrazellulär Lipase- und Proteaseaktivität Amylase-, Desoxyribonuclease- und Ribonucleaseaktivität war jedoch nicht nachzuweisen. Die Bedeutung dieser Befunde wird diskutiert. 相似文献
18.
Ahmed Ali Sirkku Niissalo Jarkko Hietanen Mikael Laine Riina Rautemaa Yrjö Konttinen 《Journal of oral pathology & medicine》2005,34(6):347-351
BACKGROUND: Chronic hyperplastic candidosis (CHC) represents a chronic opportunistic candida infection. We clarified the presence, localization and participation of alpha-defensin-1 in host response against chronic candidal stimulus. METHODS: Immunohistochemically stained CHC biopsies (n = 10) were compared to candida negative idiopathic leukoplakia (n = 10). RESULTS: In CHC alpha-defensin-1 was detected in neutrophils intravascularly, in lamina propria and in the epithelium, in part in intraepithelial microabscesses. Staining intensity of individual neutrophils varied and was associated with peri- and extracellular staining, in particular in the superficial epithelial cell layers. In controls only very few homogeneously staining neutrophils were detected intravascularly without any extracellular alpha-defensin-1 deposition. CONCLUSIONS: Neutrophils form microabscesses and respond to Candida by activation and release of alpha-defensin-1 to peri- and extracellular matrix. This together with the epithelial cell migration from the basal layer to epithelial surface leads to alpha-defensin-1 rich protective shield in the most superficial epithelial cell layers. 相似文献
19.
目的 研究兔角膜基质细胞在体外长期培养传代过程中,细胞增殖能力和胞外基质表达水平的改变。方法 取体外培养兔角膜基质细胞,由光镜对各代细胞的形态学变化进行观测。通过对各代细胞生长曲线的绘制,得出其各自的群体倍增时间;MTT法比较各代细胞增殖能力的改变。RT-PCR和Western杂交检测各代细胞中Ⅰ、Ⅲ型胶原表达水平的改变;爱茜蓝法检测糖胺聚糖(GAG)的含量。结果 体外培养兔角膜基质细胞随着传代的进程,逐渐显现衰老的形态特征。细胞群体倍增时间由第7代起显著延长(P<0.01);MTT比色法的结果亦显示,第7代细胞的增殖能力开始大幅下降(P<0.01)。第9-11代时,Ⅰ、Ⅲ型胶原在mRNA和蛋白水平的表达都有明显减少(P<0.01),降至第1代细胞的30%左右;GAG的含量也降至40%左右。结论 兔角膜基质细胞经历长期体外培养后,细胞增殖能力和胞外基质表达水平显著下降,逐渐丧失原有的功能。但作为构建组织工程化角膜的种子细胞,在它的生物学特性未发生改变之前,经3次传代培养,获取的细胞量达到组织块消化所得细胞的240倍左右,已足以用于构建之用。 相似文献
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The effects of cepharanthin on inflammatory parameters such as neutrophil chemotaxis, phagocytosis and reactive oxygen species (ROS) generation, were examined. Cepharanthin significantly decreased the levels of O2-, H2O2, and OH. generated by neutrophils. H2O2 and OH. generated in a cell-free, xanthine-xanthine oxidase system were also reduced in the presence of cepharanthin. However, the drug did not affect neutrophil chemotaxis or phagocytosis. The present study indicates that cepharanthin is an effective ROS scavenger, exerting its anti-inflammatory action by reducing the potent ROS species excessively generated in tissues and organs, especially at the sites of inflammation. 相似文献