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21.
《Immunobiology》2023,228(4):152386
Ulcerative colitis (UC) is a chronic inflammatory disease affecting the colon that can be influenced by microRNAs (miRNAs). This study aims to investigate the impact of miR-146a-5p on lipopolysaccharide (LPS)-induced Caco-2/HT-29 cell autophagy and NLRP3 inflammasome activation and the underlying mechanism, with the aim of identifying potential therapeutic targets. We used LPS to establish Caco-2/HT-29 cell models and measured cell viability by CCK-8. The levels of miR-146a-5p, RNF8, markers of NLRP3 inflammasome activation and autophagy, proteins involved in the Notch1/mTORC1 pathway, and inflammatory factors were assessed by RT-qPCR, Western blot, and ELISA. Intestinal epithelial barrier function was evaluated by measuring transepithelial electrical resistance. Autophagic flux was measured using tandem fluorescent-labeled LC3. miR-146a-5p was highly-expressed in LPS-induced Caco-2/HT-29 cells, and autophagy flux was blocked at the autolysosomal stage after LPS induction. Inhibition of miR-146a-5p suppressed NLRP3 inflammasome activation, reduced intestinal epithelial barrier damage, and facilitated autophagy inhibition in LPS-induced Caco-2/HT-29 cells. The autophagy inhibitor NH4Cl partially nullified the inhibitory effects of miR-146a-5p inhibition on NLRP3 inflammation activation. miR-146a-5p targeted RNF8, and silencing RNF8 partly abrogated the action of miR-146a-5p inhibition on promoting autophagy and inhibiting NLRP3 inflammasome activation. miR-146a-5p inhibition suppressed the Notch1/mTORC1 pathway activation by upregulating RNF8. Inhibition of the Notch1/mTORC1 pathway partially nullified the function of silencing RNF8 on inhibiting autophagy and bolstering NLRP3 inflammasome activation. In conclusion, miR-146a-5p inhibition may be a potential therapeutic approach for UC, as it facilitates autophagy of LPS-stimulated Caco-2/HT-29 cells, inhibits NLRP3 inflammasome activation, and reduces intestinal epithelial barrier damage by upregulating RNF8 and suppressing the Notch1/mTORC1 pathway.  相似文献   
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Castleman disease is a nodal based disease and very rarely involves the thymus gland. We report a 52-year-old man who was found incidentally to have a single thymic mass by computerized tomography scan. Thymectomy was performed, and the gross specimen showed a well-circumscribed, multi-loculated cystic mass. Histologic examination showed thymus involved by Castleman disease, hyaline-vascular variant. The lesion was characterized by lymphoid follicles with wide mantle zones, variably lymphocyte-depleted germinal centers with sclerotic radial blood vessels, and prominent interfollicular/stromal changes including numerous endothelial venules with sclerotic walls and hyaline sclerosis, scattered and frequent dysplastic follicular dendritic cells and foci of dystrophic calcification. Immunohistochemical analysis showed that the follicle mantle zones were composed of numerous B-cells positive for CD20, PAX5, and IgD. Antibodies specific for CD21 and CD23 highlighted prominent follicular dendritic cell networks within follicles. There was no evidence of human herpes virus 8. We searched the literature and could identify only 10 additional cases of thymic CD. Previously reported cases included 8 unicentric and 2 multicentric, classified pathologically as plasma cell variant (n = 4), hyaline vascular variant (n = 3), and mixed (n = 3). Thymectomy, as was done in the currently reported case, most often leads to the diagnosis of Castleman disease and was a mainstay of treatment in other reported cases.  相似文献   
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视力残疾的病因分析及预防   总被引:5,自引:0,他引:5  
目的:了解重庆市渝中区近5年来视力残疾的状况、特点及致残病因,提出相应的预防措施。方法:由指定眼科医师进行多次常规及特殊检查,分析403例806只眼的调查资料。结果:0~14岁儿童组人群的主要致残因素是先天遗传、屈光不正/弱视、斜视/弱视、角膜病和视神经病变;60岁以上老年人群为青光眼、白内障、角膜病、视网膜病变和视神经病变;其他人群依次为高度近视网脱及黄斑变性、眼外伤、角膜病、青光眼和视网膜病变。结论:对不同年龄段的人群应制定相应的预防视残措施。重点开展孕期保健工作及遗传咨询,加大眼部疾病预防知识宣传,预防眼部感染和外伤,积极治疗原发病。  相似文献   
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采用RT-PCR法提取天然内生抗菌多肽elafin的基因,通过测序确认后亚克隆构建真核表达载体pEGFP-N1-elafin,再转染至肺上皮细胞A549,荧光显微镜观察pEGFP-N1-elafin在细胞中表达及定位,采用Northern杂交、ELISA检测法分别从转录及蛋白质水平分析表达情况,最后通过酶切电泳鉴定证实真核表达载体pEGFP-N1-elafin构建成功,其转染细胞中有elafin的基因表达,且细胞上清液中elafin含量证实其主要是分泌性表达。Elafin基因cDNA真核表达载体的成功构建以及主要呈分泌性表达的特点显示了极具意义的潜在应用价值。  相似文献   
25.
OBJECTIVE: To investigate the relation between TGF-beta1 in allograft and chronic allograft nephropathy (CAN). METHODS: The levels of urine TGF-beta1 were tested in 146 recipients whose renal function were normal from September 1, 2000 to January 31, 2001. Twenty recipients with the highest level of urine TGF-beta1 were classified in group A, while 20 other recipients with the lowest level of urine TGF-beta1 were classified in group B. In these two groups biopsies were carried out in 14 cases and 12 cases respectively, and TGF-beta1 mRNA in the biopsies was measured by RT-PCR. The levels of TGF-beta1 in the blood were also measured in the two groups. Three years later, the renal function was compared between the two groups. Biopsies were carried out in renal recipients whose creatinine is higher than normal. RESULTS: The level of TGF-beta1 in the blood showed no significant difference between the two groups; 3 years after transplantation, the loss of renal function in group A was severer than that in group B. The number levels of CAN cases in group A was larger than that in group B. The expression levels of TGF-beta1 and TGF-beta1 mRNA of the allografts were higher in group A than in group B; there were statistically significant differences between the two groups. CONCLUSION: The findings suggest that there is an association between TGF-beta1 in kidneys and CAN. The level of urine TGF-beta1 after renal transplantation may predict future renal function.  相似文献   
26.
无创正压通气治疗的护理   总被引:5,自引:0,他引:5  
通过17例呼吸衰竭患者应用无创正压通气(NIPPV)的临床观察与护理,结合治疗前后血气参数值的对比分析,总结出以下护理体会:心理护理,选择合适的体位及鼻(面)罩是应用NIPPV的前提;防止漏气和面部皮肤压迫性损伤,保持呼吸道通畅,密切观察患者通气效果及呼吸机性能是应用NIPPV的护理重点;密切观察患者病情变化,进行氧疗,协助患者排痰是NIPPV治疗后的护理措施。  相似文献   
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The interaction between drug products and polymeric packaging materials is an important topic in the pharmaceutical industry and often associated with high costs because of the required elaborative interaction studies. Therefore, a theoretical prediction of such interactions would be beneficial. Often, material parameters such as the octanol water partition coefficient are used to predict the partitioning of migrant molecules between a solvent and a polymeric packaging material. Here, we present the investigation of the partitioning of various migrant molecules between polymers and solvents using molecular dynamics simulations for the calculation of interaction energies. Our results show that the use of a model for the interaction between the migrant and the polymer at atomistic detail can yield significantly better results when predicting the polymer solvent partitioning than a model based on the octanol water partition coefficient.  相似文献   
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