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81.
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   
82.
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   
83.
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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85.
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   
86.
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   
87.
Malignant melanoma is a highly aggressive skin cancer characterized by an elevated grade of tumor cell plasticity. Such plasticity allows adaptation of melanoma cells to different hostile conditions and guarantees tumor survival and disease progression, including aggressive features such as drug resistance. Indeed, almost 50% of melanoma rapidly develop resistance to the BRAFV600E inhibitor vemurafenib, with fast tumor dissemination, a devastating consequence for patients’ outcomes. Vasculogenic mimicry (VM), the ability of cancer cells to organize themselves in perfused vascular-like channels, might sustain tumor spread by providing vemurafenibresistant cancer cells with supplementary ways to enter into circulation and disseminate. Thus, this research aims to determine if vemurafenib resistance goes with the acquisition of VM ability by aggressive melanoma cells, and identify a driving molecule for both vemurafenib resistance and VM. We used two independent experimental models of drug-resistant melanoma cells, the first one represented by a chronic adaptation of melanoma cells to extracellular acidosis, known to drive a particularly aggressive and vemurafenib-resistant phenotype, the second one generated with chronic vemurafenib exposure. By performing in vitro tube formation assay and evaluating the expression levels of the VM markers EphA2 and VE-cadherin by Western blotting and flow cytometer analyses, we demonstrated that vemurafenib-resistant cells obtained by both models are characterized by an increased ability to perform VM. Moreover, by exploiting the CRISPR-Cas9 technique and using the urokinase plasminogen activator receptor (uPAR) inhibitor M25, we identified uPAR as a driver of VM expressed by vemurafenib-resistant melanoma cells. Thus, uPAR targeting may be successfully leveraged as a new complementary therapy to inhibit VM in drug-resistant melanoma patients, to counteract the rapid progression and dissemination of the disease.  相似文献   
88.
《药学学报(英文版)》2020,10(8):1453-1475
Angiokinases, such as vascular endothelial-, fibroblast- and platelet-derived growth factor receptors (VEGFRs, FGFRs and PDGFRs) play crucial roles in tumor angiogenesis. Anti-angiogenesis therapy using multi-angiokinase inhibitor has achieved great success in recent years. In this study, we presented the design, synthesis, target identification, molecular mechanism, pharmacodynamics (PD) and pharmacokinetics (PK) research of a novel triple-angiokinase inhibitor WXFL-152. WXFL-152, identified from a series of 4-oxyquinoline derivatives based on a structure–activity relationship study, inhibited the proliferation of vascular endothelial cells (ECs) and pericytes by blocking the angiokinase signals VEGF/VEGFR2, FGF/FGFRs and PDGF/PDGFRβ simultaneously in vitro. Significant anticancer effects of WXFL-152 were confirmed in multiple preclinical tumor xenograft models, including a patient-derived tumor xenograft (PDX) model. Pharmacokinetic studies of WXFL-152 demonstrated high favourable bioavailability with single-dose and continuous multi-dose by oral administration in rats and beagles. In conclusion, WXFL-152, which is currently in phase Ib clinical trials, is a novel and effective triple-angiokinase inhibitor with clear PD and PK in tumor therapy.  相似文献   
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