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81.
The present study was designed to explore the effects of B-cell activating factor receptor (BAFF-R) siRNA encapsulated nanoparticles on collagen-induced arthritis (CIA). BAFF-R siRNA encapsulated nanoparticles (NP-siBAFF-R) were constructed using a double emulsion method and was characterized by dynamic light scattering and transmission electron microscopy. Cellular uptake of nanoparticles was determined using flow cytometry. The CIA mouse model was established and the mice were intravenously injected with nanoparticles. NP-siBAFF-R effectively decreased the expression of BAFF-R in B cells and facilitated the delivery of siRNA into B cells. Treatment of NPsiBAFF-R ameliorated rheumatoid arthritis (RA) symptoms in the CIA mouse model via decreasing the arthritis score, mean ankle diameter, the levels of anti-collagen IgG in serum and increasing the expression of collagen type II and osteocalcin in dissected joint tissues. Additionally, treatment of NPsiBAFF-R decreased the percentage and number of B cells and inhibited the production of pro-inflammatory cytokines in RA mice. These results demonstrate that NP-siBAFF-R may provide an effective strategy for RA treatment. 相似文献
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84.
《Vaccine》2020,38(31):4783-4791
A novel coronavirus (CoV), Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in late 2019 in Wuhan, China and has since spread as a global pandemic. Safe and effective vaccines are thus urgently needed to reduce the significant morbidity and mortality of Coronavirus Disease 2019 (COVID-19) disease and ease the major economic impact. There has been an unprecedented rapid response by vaccine developers with now over one hundred vaccine candidates in development and at least six having reached clinical trials. However, a major challenge during rapid development is to avoid safety issues both by thoughtful vaccine design and by thorough evaluation in a timely manner. A syndrome of “disease enhancement” has been reported in the past for a few viral vaccines where those immunized suffered increased severity or death when they later encountered the virus or were found to have an increased frequency of infection. Animal models allowed scientists to determine the underlying mechanism for the former in the case of Respiratory syncytial virus (RSV) vaccine and have been utilized to design and screen new RSV vaccine candidates. Because some Middle East respiratory syndrome (MERS) and SARS-CoV-1 vaccines have shown evidence of disease enhancement in some animal models, this is a particular concern for SARS-CoV-2 vaccines. To address this challenge, the Coalition for Epidemic Preparedness Innovations (CEPI) and the Brighton Collaboration (BC) Safety Platform for Emergency vACcines (SPEAC) convened a scientific working meeting on March 12 and 13, 2020 of experts in the field of vaccine immunology and coronaviruses to consider what vaccine designs could reduce safety concerns and how animal models and immunological assessments in early clinical trials can help to assess the risk. This report summarizes the evidence presented and provides considerations for safety assessment of COVID-19 vaccine candidates in accelerated vaccine development. 相似文献
85.
Shaoxian Xu Xiaoyan Wang Jing Zhao Suzhen Yang Lei Dong Bin Qin 《Fundamental & clinical pharmacology》2020,34(4):433-443
Visceral hypersensitivity (VH) is common in irritable bowel syndrome (IBS), and female patients are more likely to seek healthcare services for IBS-related abdominal pain. Oestrogen has been reported to mediate pain modulation via its receptor, and mast cells are known to participate in the development of visceral hypersensitivity. Our previous studies showed that the G-protein-coupled oestrogen receptor (GPER, also known as GPR30) was expressed by mast cells in human colonic tissues and was associated with IBS type and severity of visceral pain. However, whether GPER is involved in oestrogen-dependent visceral hypersensitivity via mast cell degranulation is still unknown. Rats were subjected to wrap partial restraint stress to induce visceral hypersensitivity and were ovariectomized (OVX) to eliminate the effects of oestrogen on visceral hypersensitivity. OVX rats were treated with oestrogen, an oestrogen receptor α and β antagonist (ICI 182.780), a GPER antagonist (G15) or a GPER agonist (G1), to evaluate the effects of oestrogen via its receptor. The colorectal distention test was performed to assess visceral sensitivity. Immunofluorescence studies were performed to evaluate GPER and mast cell tryptase co-expression. Mast cell number with degranulation was detected by specific staining. Mast cell tryptase expression in rat colon was also investigated by Western blot and immunohistochemistry. Substance P and histamine expression were examined by ELISA. GPER was expressed by the majority of tryptase-positive mast cells in the colonic mucosa. Stressed rats showed increased visceral sensitivity, increased mast cell degranulation, mast cell tryptase expression, and increased colon histamine levels. Ovariectomy reduced stress-induced VH in female rats and decreased mast cell degranulation, mast cell tryptase expression, and histamine levels, whereas oestrogen replacement reversed these effects. In OVX rats, the GPER antagonist G15 counteracted the enhancing effects of oestrogen on stress-induced VH, mast cell degranulation, mast cell tryptase, and histamine expression, whereas VH was preserved after treatment with ICI 182.780. On the other hand, pretreatment with the selective GPER agonist G1 at doses between 1 and 20 μg/kg significantly increased VH, mast cell tryptase, and histamine expression in OVX-stressed rats, mimicking the effects of oestrogen. GPER plays a pivotal role in the regulation of mast cell degranulation, mast cell tryptase expression, and histamine levels and contributes to the development of colonic hypersensitivity in a female rat model of IBS. 相似文献
86.
探讨慢性阻塞性肺病(COPD)患者的可溶性髓系细胞触发受体-1(sTREM-1)、结缔组织生长因子(CTGF)、亲环素-A(CyPA)水平与其病情严重程度的相关性。ELISA检测COPD患者与健康人血清sTREM-1、CTGF、CyPA水平。结果显示,COPD患者sTREM-1、CTGF、CyPA水平高于健康人。随着肺功能分级的增加,COPD患者血清中sTREM-1、CTGF、CyPA水平也随之增加。sTREM-1、CTGF、CyPA水平与FEV1/FVC呈现显著负相关性(P<0.05)。Logistic回归分析显示,sTREM-1、CTGF、CyPA水平是严重COPD的影响因素。结果说明,COPD患者血清sTREM-1、CTGF、CyPA水平显著升高,并且与患者肺功能指标显著相关,可用于判断COPD患者的病情严重程度。 相似文献
87.
《Journal of vascular and interventional radiology : JVIR》2020,31(6):925-933
PurposeTo determine predictors of survival after transarterial radioembolization of hepatic metastases from breast cancer.Materials and MethodsTwenty-four patients with chemotherapy-refractory hepatic metastases from breast cancer who underwent radioembolization from 2013 to 2018 were evaluated based on various demographic and clinical factors before and after treatment. Overall survival (OS) was estimated by Kaplan–Meier method. Log-rank analysis was performed to determine predictors of prolonged OS from the time of first radioembolization and first hepatic metastasis diagnosis.ResultsMedian OS times were 35.4 and 48.6 months from first radioembolization and time of hepatic metastasis diagnosis, respectively. Radioembolization within 6 months of hepatic metastasis diagnosis was a positive predictor of survival from first radioembolization, with median OS of 38.9 months vs 22.1 months for others (P = .033). Estrogen receptor (ER)–positive status predicted prolonged survival (38.6 months for ER+ vs 5.4 months for ER−; P = .005). The presence of abdominal pain predicted poor median OS: 12.8 months vs 38.6 months for others (P < .001). The presence of ascites was also a negative predictor of OS (1.7 months vs 35.4 months for others; P = .037), as was treatment-related grade ≥ 2 toxicity at 3 months (5.4 months vs 38.6 months for others; P = .017).ConclusionsIn patients with metastatic breast cancer, radioembolization within 6 months of hepatic metastasis diagnosis and ER+ status appear to be positive predictors of prolonged survival. Conversely, baseline abdominal pain, baseline ascites, and treatment-related grade ≥ 2 toxicity at 3 months after treatment appear to be negative predictors of OS. 相似文献
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89.
Angiogenesis plays an important role in the occurrence and development of tumors. Registered tyrosine kinase inhibitors targeting vascular endothelial growth factor reduce angiogenesis. Apatinib, a tyrosine kinase inhibitor, can specifically inhibit vascular endothelial growth factor receptor 2, showing encouraging anti-tumor effects in a variety of tumors including advanced hepatocellular carcinoma(HCC). This article intends to review the clinical research and application prospects of apatinib in the field of HCC. 相似文献
90.
目的研究二妙散对类风湿关节炎(RA)调控基因Toll样受体(TLR4)和重组牛磷酸肌醇3激酶A(PI3KA)表达的影响。方法通过构建Wistar大鼠胶原诱导性关节炎(CIA)模型,不同浓度二妙散灌胃治疗,酶联免疫吸附试验(ELISA)检测血清中炎症因子的表达,苏木精-伊红(HE)染色进行病理学分析,实时荧光定量聚合酶链反应(qRT-PCR)分析TLR4和PI3KA的表达特性。结果二妙散组与CIA模型组相比,脾脏指数差异无统计学意义(P>0.05);CIA模型组与对照组相比,脾脏指数显著降低,差异有统计学意义(P<0.05);二妙散组滑膜组织炎性细胞较少;较正常组白细胞介素(IL)-6和肿瘤坏死因子(TNF)-α表达量极显著降低,差异有统计学意义(P<0.01,P<0.05),较模型组显著降低,差异有统计学意义(P<0.05);随二妙散浓度增加IL-37表达量显著增加,差异有统计学意义(P<0.05,P<0.01)。模型组大鼠关节中IL-6、TLR4和PI3KA mRNA水平表达量极显著高于对照组和甲氨蝶呤组,差异有统计学意义(P<0.01)。结论本实验成功构建CIA大鼠模型,TLR4和PI3KA在不同实验组大鼠关节组织中均有不同程度的表达,说明TLR4和PI3KA参与CIA大鼠炎性反应的形成,介导RA炎性因子的形成和发展,二妙散对于减少炎症因子和增加抑炎因子的表达具有重要作用,具体作用机制需进一步研究证实。 相似文献