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It is well recognized that the world population is ageing rapidly. Therefore, it is important to understand ageing processes at the cellular and molecular levels to predict the onset of age‐related diseases and prevent them. Recent research has focused on the identification of ageing biomarkers, including those associated with the properties of the Golgi apparatus. In this context, Golgi‐mediated glycosylation of proteins has been well characterized. Additionally, other studies show that the secretion of many compounds, including pro‐inflammatory cytokines and extracellular matrix–degrading enzymes, is modified during ageing, resulting in physical and functional skin degradation. Since the Golgi apparatus is a central organelle of the secretory pathway, we investigated its structural organization in senescent primary human dermal fibroblasts using confocal and electron microscopy. In addition, we monitored the expression of Golgi‐related genes in the same cells. Our data showed a marked alteration in the Golgi morphology during replicative senescence. In contrast to its small and compact structure in non‐senescent cells, the Golgi apparatus exhibited a large and expanded morphology in senescent fibroblasts. Our data also demonstrated that the expression of many genes related to Golgi structural integrity and function was significantly modified in senescent cells, suggesting a relationship between Golgi apparatus function and ageing.  相似文献   
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ObjectivesMeshes/matrices are commonly used in immediate breast reconstruction. There are few studies comparing biological and synthetic meshes and it is unknown what type of mesh gives the best long-term results. The aim of this study was to compare long-term health-related quality of life (HrQoL) and patient satisfaction in implant-based immediate breast reconstruction with a biological mesh (Surgisis®) with that of patients reconstructed with a synthetic mesh (TIGR ® Matrix Surgical Mesh).Material and methodsBoth cohorts were prospectively included and consecutively operated. Clinical data was collected. HrQoL was evaluated with EuroQoL-5 dimension – 3 levels questionnaire (EQ-5D-3L) and the Hospital Anxiety and Depression Scale (HADS) and the Breast-Q.Results and conclusionSeventy-one patients were operated on in the biological group and 49 in the synthetic group. The response rates were 75 and 84 per cent, respectively. Mean follow-up time was 74 months and 23 months, respectively. There were no statistical differences in satisfaction and quality of life between the two groups. Complications and radiation seem to lead to a lower satisfaction. Our findings could indicate that biological and synthetic meshes give an equal long-term result as regards patients’ perceived quality of life.  相似文献   
4.
《Vaccine》2019,37(31):4382-4391
Cancer-associated fibroblasts (CAFs), major components of the tumor microenvironment (TME), promote tumor growth and metastasis and inhibit the anti-tumor immune response. We previously constructed a DNA vaccine expressing human FAPα, which is highly expressed by CAFs, to target these cells in the TME, and observed limited anti-tumor effects in the 4T1 breast cancer model. When the treatment time was delayed until tumor nodes formed, the anti-tumor effect of the vaccine completely disappeared. In this study, to improve the safety and efficacy, we constructed a new FAPα-targeted vaccine containing only the extracellular domain of human FAPα with a tissue plasminogen activator signal sequence for enhanced antigen secretion and immunogenicity. The number of CAFs was more effectively reduced by CD8+ T cells induced by the new vaccine. This resulted in decreases in CCL2 and CXCL12 expression, leading to a significant decrease in the ratio of myeloid-derived suppressor cells in the TME. Moreover, when mice were treated after the establishment of tumors, the vaccine could still delay tumor growth. To facilitate the future application of the vaccine in clinical trials, we further optimized the gene codons and reduced the homology between the vaccine and the original sequence, which may be convenient for evaluating the vaccine distribution in the human body. These results indicated that the new FAPα-targeted vaccine expressing an optimized secreted human FAPα induced enhanced anti-tumor activity by reducing the number of FAPα+ CAFs and enhancing the recruitment of effector T cells in the 4T1 tumor model mice.  相似文献   
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Fibroblasts incorporated within collagen gels induce a cell-mediated contraction of the gel to form a three-dimensional, tissue-like structure by a mechanism thought to mimic wound contraction in vivo . In this study a gel contraction model was used to investigate the ability of fibroblasts derived from adult gingiva, adult skin and fetal skin to organise a collagen matrix. In addition the effects of interleukin-1β (IL-1β) on the contraction process was also investigated. Over the concentration range 5-50 U/ml, IL-1β induced a statistically significant inhibition of gel contraction in all fibroblast cell types ( P <0.05), although fetal fibroblasts appeared least responsive and gingival fibroblasts most responsive to the inhibitory effects of this cytokine. Comparison of gel contraction by the different fibroblast strains indicated that fetal and gingival fibroblasts shared similar contraction kinetics. For the adult skin fibroblasts, three of five strains studied showed significantly diminished levels of gel contraction compared to fetal and gingival cells. This apparent difference in fibroblast phenotype may, at least in part, explain the fetal-like wound healing pattern seen in the oral mucosa.  相似文献   
6.
A 50-year-old Japanese man had a blue-black patch on the dorsum of his right wrist. Light and electron microscopic study of the lesion revealed dermal melanocytes containing mature melanosomes, predominantly in the upper dermis. This case was diagnosed as acquired dermal melanocytosis confined to the right wrist.  相似文献   
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目的:探讨P物质抑制剂-辣椒素及bFGF抗体单独或联合使用对体外培养的人体增生性瘢痕成纤维细胞增殖的影响。方法:体外培养12例增生性瘢痕组织的成纤维细胞,分别加入不同浓度的辣椒素或/和bFGF抗体,培养24h后观察细胞形态学变化,并用MTT法检测细胞增殖抑制率。结果:所有不同浓度的辣椒素(2.5,5,20,40,60,80mg/L)均能使细胞皱缩、坏死,抑制细胞增殖,其抑制作用随剂量增大而增加。中高浓度bFGF抗体(40,80mg/L)也可促使细胞皱缩、坏死,抑制细胞增殖,其抑制作用也随剂量增大而增加。辣椒素与bFGF抗体联合应用对成纤维细胞抑制作用较单独使用效果更显著(P﹤0.05)。结论:辣椒素及bFGF抗体可抑制增生性瘢痕成纤维细胞增殖,其抑制作用随浓度增加而增加,两者联合使用有协调作用,本研究结果可能在增生性瘢痕的治疗提供新的思路和手段。  相似文献   
8.
目的:观察体外联合培养的成纤维细胞对平滑肌细胞形态和增殖的影响,为研究成纤维细胞和平滑肌细胞生物学特性和相互关系以及体外构建含此两种细胞的组织工程皮肤提供理论和实践基础。方法:在体外分别分离培养成纤维细胞和平滑肌细胞并常规传代培养。模拟组织工程皮肤的结构及成纤维细胞和平滑肌细胞间的相互影响途径,按照不同比例(平滑肌细胞:成纤维细胞=1:1,1:2,1:3)建立以胶原凝胶为基质的成纤维细胞与平滑肌细胞联合培养模型。应用荧光标记、组织学观察和MTT法对平滑肌细胞的形态和代谢进行研究。结果:联合培养模型法可以有效地建立起成纤维细胞和平滑肌细胞的相互影响模式。1:1组的成纤维细胞对联合培养的平滑肌细胞增殖有促进作用,1:3组的促增殖作用则不明显。结论:1:1联合培养的成纤维细胞对平滑肌细胞增殖有促进作用,对它们体外培养和扩增以及相互关系的研究对阐明这两种细胞组合作为真皮替代物种子细胞具有重要的意义。  相似文献   
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The expression of mRNA encoding the inflammatory cytokines interleukin-1α (IL-1α), interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8) and tumor necrosis factor α (TNF-α) have been examined in radicular cysts by in situ hybridization. Furthermore, the biological activity of the contents of radicular cysts (RCC) has been assayed by adding extracts of RCC to cultured human gingival fibroblasts (HGFs) and analyzing the culture medium for the release of inflammatory cytokines. In the epithelial layer, keratinocytes expressed all cytokine mRNAs examined at various levels. Basal layer cells expressed mRNA for each cytokine. In the subepithelial granulation tissue of the cysts, fibroblasts and macrophages expressed mRNA for IL-6, IL-8, IL-1β and TNF-α mRNA at varying levels; especially clear expression of TNF-α and IL-1β mRNA was detected on macrophages. The infiltrating lymphoid cells, largely composed of T cells and plasma cells, expressed these cytokine mRNAs, especially those encoding IL-6 and IL-8, at various levels. In vitro analysis indicated dose-dependent release of both IL-6 and IL-8 by HGFs in response to RCC. After heating to 100°C for 10 min, RCC almost completely failed to stimulate IL-6 release from HGFs. Furthermore, anti-IL-1β antibody (neutralization test) did not prevent the stimulation of IL-6 release by RCC. Significant amounts of IL-6 and IL-8 were detected in RCC in two cases, and a trace amount of IL-1β was detected in one case. This study demonstrated the wide expression of mRNA encoding inflammatory cytokines in radicular cyst tissues, and RCC itself was capable of stimulating 1L-6 and 1L-8 production from HGFs.  相似文献   
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