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Since their inception in the 1960s–70s, mesenchymal stem/stromal cells (MSCs) have gained interest because of their differentiation potential, anti-inflammatory effects, and immune-modulating properties. Both cell-based and cell-free MSC treatments show healing capacity in injured tissues. Cell-based treatment comprises MSCs and all secreted products, whereas cell-free treatments include only the secreted products. MSCs are therapeutically administered to many damaged organs owing to their efficacy. Specifically, the eye is a unique organ system to study the effects of MSCs, as treatment is easily applied and measured owing to its external location. The eye holds an immune-privileged status, wherein inflammation and immune responses are innately down-regulated. As excessive inflammation in the cornea often leads to fibrosis and irreversible corneal hazing, many studies have investigated the anti-inflammatory and immune-modulating capacities of MSCs. Decades of research suggest that MSCs modulate the immune response by secreting cytokines, growth factors, and extracellular matrix proteins that inhibit the infiltration of inflammatory cells following injury and promote a healing phenotype via M2 macrophage polarization. MSCs have also shown trans-differentiation potential into cornea-specific cell types during the wound healing process, such as corneal epithelial, stromal, or endothelial cells. This review discusses recent investigations of MSC treatment in the cornea, focusing on therapeutic efficacy, mechanisms, and future directions. 相似文献
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《Journal of vascular and interventional radiology : JVIR》2022,33(3):249-254.e1
An ovine iliac vein thrombosis model was devised to test a wall-contacting rotational thrombectomy device. Thrombosis was successfully induced in 9 sheep with an average clot length of 31 mm ± 12 and >60% vessel occlusion on angiography. The thrombus was subsequently removed, maintaining normal intraoperative pulmonary arterial pressure (5.9 mm Hg ± 3.6) and complete distal reperfusion after thrombectomy. Additionally, the sheep were without signs of vascular trauma or embolic complications on gross necropsy and histopathologic analysis. The findings from this study support the use of an ovine iliac deep vein thrombosis model for testing of a lower extremity thrombectomy device. 相似文献
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目的探讨放疗干预对宫颈癌荷瘤小鼠的抑瘤作用及其对辅助性T细胞1(Th1)/Th2细胞比例的影响。方法建立宫颈癌荷瘤小鼠模型,随机分为荷瘤组和放疗组,每组各10只,另设对照组10只。放疗组进行放疗干预14天,荷瘤组和对照组不治疗。放疗后4、6、8、10、12、14天测量肿瘤体积;末次治疗后,ELISA法测定血清干扰素-γ(IFN-γ)、白介素-2(IL-2)、IL-4、IL-10含量;计算抑瘤率、胸腺指数和脾脏指数;HE染色观察肿瘤组织学变化;TUNEL染色观察肿瘤组织细胞凋亡情况;流式细胞术检测脾脏Th1/Th2细胞比例;RT-qPCR和Western blot检测脾脏T盒子转录因子(T-bet)、GATA结合蛋白3(GABA-3)mRNA和蛋白表达。结果与荷瘤组比较,放疗组小鼠4、6、8、10、12、14天肿瘤体积及瘤质量减小,血清IL-2、IFN-γ升高,IL-4、IL-10降低,胸腺指数、脾脏指数升高,Th1细胞比例、Th1/Th2增加,Th2细胞比例减少,T-bet mRNA和蛋白及T-bet/GATA-3表达升高,GATA-3 mRNA和蛋白表达降低(P<0.05)。HE染色显示,荷瘤组肿瘤细胞数量较多,核大深染,无明显坏死;放疗组肿瘤细胞数量减少,出现大量坏死组织。TUNEL染色显示,荷瘤组TUNEL阳性细胞较少,放疗组TUNEL阳性细胞明显增多。结论放疗对宫颈癌荷瘤小鼠具有明显抑瘤作用,可能是通过调节T-bet/GATA-3表达,促进Th1/Th2分化平衡,增强机体免疫功能发挥作用。 相似文献
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《Journal of vascular and interventional radiology : JVIR》2022,33(10):1213-1221.e5
PurposeTo investigate the pharmacokinetics (PK) and early effects of conventional transarterial chemoembolization (TACE) using sorafenib and doxorubicin on tumor necrosis, hypoxia markers, and angiogenesis in a rabbit VX2 liver tumor model.Materials and MethodsVX2 tumor-laden New Zealand White rabbits (N = 16) were divided into 2 groups: 1 group was treated with hepatic arterial administration of ethiodized oil and doxorubicin emulsion (DOX-TACE), and the other group was treated with ethiodized oil, sorafenib, and doxorubicin emulsion (SORA-DOX-TACE). Animals were killed within 3 days of the procedure. Levels of sorafenib and doxorubicin were measured in blood, tumor, and adjacent liver using mass spectrometry. Tumor necrosis was determined by histopathological examination. Intratumoral hypoxia-inducible factor (HIF) 1α, vascular endothelial growth factor (VEGF), and microvessel density (MVD) were determined by immunohistochemistry.ResultsThe median intratumoral concentration of sorafenib in the SORA-DOX-TACE group was 17.7 μg/mL (interquartile range [IQR], 7.42–33.5 μg/mL), and its maximal plasma concentration (Cmax) was 0.164 μg/mL (IQR, 0.0798–0.528 μg/mL). The intratumoral concentration and Cmax of doxorubicin were similar between the groups: 4.08 μg/mL (IQR, 3.18–4.79 μg/mL) and 0.677 μg/mL (IQR, 0.315–1.23 μg/mL), respectively, in the DOX-TACE group and 1.68 μg/mL (IQR, 0.795–4.08 μg/mL) and 0.298 μg/mL (IQR, 0.241–0.64 μg/mL), respectively, in the SORA-DOX-TACE group. HIF-1α expression was increased in the SORA-DOX-TACE group than in the DOX-TACE group. Tumor volume, tumor necrosis, VEGF expression, and MVD were similar between the 2 groups.ConclusionsThe addition of sorafenib to DOX-TACE delivered to VX2 liver tumors resulted in high intratumoral and low systemic concentrations of sorafenib without altering the PK of doxorubicin. 相似文献