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1.
Little is known about the effects on hyaluronan (HA) metabolism of UVA radiation. This study demonstrates that the secretion of HA by human dermal fibroblasts (HDFs) is downregulated by UVA, accompanied by the down- and upregulation of mRNA and protein levels of the HA-synthesizing enzyme (HAS2) and the HA-degrading protein, HYaluronan Binding protein Involved in HA Depolymerization(HYBID), respectively. Signaling analysis revealed that the exposure distinctly elicits activation of the p38/MSK1/CREB/c-Fos/AP-1 axis, the JNK/c-Jun axis, and the p38/ATF-2 axis, but downregulates the phosphorylation of NF-kB and JAK/STAT3. A signal inhibition study demonstrated that the inhibition of p38 significantly abrogates the UVA-accentuated mRNA level of HYBID. Furthermore, the inhibition of STAT3 significantly downregulates the level of HAS2 mRNA in non-UVA exposed HDFs. Analysis using siRNAs demonstrated that transfection of ATF-2 siRNA but not c-Fos siRNA abrogates the increased protein level of HYBID in UVA-exposed HDFs. An inhibitor of protein tyrosine phosphatase but not of protein serine/threonine phosphatase restored the diminished phosphorylation level of STAT3 at Tyr 705, accompanied by a significant abolishing effect on the decreased mRNA expression level of HAS2. Silencing with a protein tyrosine phosphatase PTP-Meg2 siRNA revealed that it abrogates the decreased phosphorylation of STAT3 at Tyr 705 in UVA-exposed HDFs. These findings suggest that the UVA-induced decrease in HA secretion by HDFs is attributable to the down- and upregulation of HAS2 and HYBID expression, respectively, changes that are mainly ascribed to the inactivated signaling of the STAT3 axis due to the activated tyrosine protein phosphatase PTP-Meg2 and the activated signaling of the p38/ATF2 axis, respectively.  相似文献   
2.
Cashmere is initiated and develops in the fetal stages and the number and density of secondary hair follicles (SHFs) determine cashmere production and quality. Growing evidence indicates that both microRNA (miRNA) and long non-coding RNA (lncRNA) play an indispensable role in hair follicle (HF) growth and development. However, little is known about miRNAs, lncRNAs, and their functions as well as their interactions during cashmere initiation and development. Here, based on lncRNA and miRNA high-throughput sequencing and bioinformatics analysis, we identified 10,485 lncRNAs, 40,639 mRNAs, and 605 miRNAs in cashmere goat skin during HF induction, organogenesis, and cytodifferentiation stages. Among them, 521 lncRNAs, 5976 genes, and 204 miRNAs were differentially expressed (DE). KEGG analysis of DE genes indicated that ECM–receptor interaction and biosynthesis of amino acids were crucial for HF development. Notch, TGF-beta, and Wnt signaling pathways were also identified, which are conventional pathways associated with HF growth and development. Then, the ceRNA regulatory network was constructed, and the impact of lncRNA H19 was investigated in dermal papilla (DP) cells. The MTT, CCK-8, and EdU assays showed that the viability and proliferation of DP cells were promoted by H19, and mechanistic studies suggested that H19 performed its function through the chi-miR-214-3p/β-catenin axis. The present study created a resource for lncRNA, miRNA, and mRNA studies in cashmere morphogenesis. It could contribute to a better understanding of the molecular mechanism of ncRNAs involved in the regulation of HF growth and development.  相似文献   
3.
成纤维细胞是构建组织工程化真皮的种子细胞,实现成纤维细胞的低温保存对成功保存组织工程化真皮有着重要的意义.采用三种不同的低温保存方法对成纤维细胞进行低温保存实验;详细介绍这三种方法的操作过程;并从细胞存活率、降温过程中的温度变化情况、操作时所需仪器设备及所耗时间等方面对这三种方法进行了比较.同时研究了DMSO的浓度、预处理时间及预处理温度等因素对成纤维细胞存活率的影响.  相似文献   
4.
采取浸渍冻干的方法将硝酸银( AgNO3)与脱细胞猪真皮基质(pADM)复合,制备出含银的脱细胞猪真皮材料.测定了材料的力学性能和吸湿性,采用抑菌圈法表征了材料的抗菌性能,通过细胞培养和经口急毒性实验考察了材料的生物相容性.研究结果表明,含银脱细胞猪真皮材料力学性能和吸湿性都非常好,对大肠杆菌和金色葡萄球菌均具有明显的抗菌作用,细胞毒性为0级,无明显经口急性毒性.证明它是一种抗菌效果明显且无细胞毒性的材料,适宜作为创伤敷料在临床上推广.  相似文献   
5.
Excess amounts of redox stress and failure to regulate homeostatic levels of reactive species are associated with several skin pathophysiologic conditions. Nonmalignant cells are assumed to cope better with higher reactive oxygen and nitrogen species (RONS) levels. However, the effect of periodic stress on this balance has not been investigated in fibroblasts in the field of plasma medicine. In this study, we aimed to investigate intrinsic changes with respect to cellular proliferation, cell cycle, and ability to neutralize the redox stress inside fibroblast cells following periodic redox stress in vitro. Soft jet plasma with air as feeding gas was used to generate plasma-activated medium (PAM) for inducing redox stress conditions. We assessed cellular viability, energetics, and cell cycle machinery under oxidative stress conditions at weeks 3, 6, 9, and 12. Fibroblasts retained their usual physiological properties until 6 weeks. Fibroblasts failed to overcome the redox stress induced by periodic PAM exposure after 6 weeks, indicating its threshold potential. Periodic stress above the threshold level led to alterations in fibroblast cellular processes. These include consistent increases in apoptosis, while RONS accumulation and cell cycle arrest were observed at the final stages. Currently, the use of NTP in clinical settings is limited due to a lack of knowledge about fibroblasts’ behavior in wound healing, scar formation, and other fibrotic disorders. Understanding fibroblasts’ physiology could help to utilize nonthermal plasma in redox-related skin diseases. Furthermore, these results provide new information about the threshold capacity of fibroblasts and an insight into the adaptation mechanism against periodic oxidative stress conditions in fibroblasts.  相似文献   
6.
Intervertebral disc (IVD) diseases are common spinal disorders that cause neck or back pain in the presence or absence of an underlying neurological disorder. IVD diseases develop on the basis of degeneration, and there are no established treatments for degeneration. IVD diseases may therefore represent a candidate for the application of regenerative medicine, potentially employing normal human dermal fibroblasts (NHDFs) induced to differentiate into nucleus pulposus (NP) cells. Here, we used a three-dimensional culture system to demonstrate that ectopic expression of MYC, KLF4, NOTO, SOX5, SOX6, and SOX9 in NHDFs generated NP-like cells, detected using Safranin-O staining. Quantitative PCR, microarray analysis, and fluorescence-activated cell sorting revealed that the induced NP cells exhibited a fully differentiated phenotype. These findings may significantly contribute to the development of effective strategies for treating IVD diseases.  相似文献   
7.
8.
丙三醇缩水甘油醚改性脱细胞猪真皮基质的研究   总被引:1,自引:0,他引:1  
研究了丙三醇缩水甘油醚(GPE)改性脱细胞猪真皮基质材料(pADM)的基本性能.通过考察不同温度、pH值、用量和反应时间对改性材料(GPE-pADM)性能的影响,初步探讨了改性条件与改性材料性能之间的关系.实验结果表明:反应温度37~42℃,pH值10.0~10.5,反应时间48-72h,用量8%时综合性能较好.交联后材料的接触角明显降低,且随着GPE用量的增加,接触角降低程度增大,表明交联提高了材料的亲水性能.  相似文献   
9.
ThreeHypselodoris species,H. villafranca, H. cantabrica, and H. tricolor, have been studied in order to further investigate the defensive strategies of Chromodorididae mollusks from Iberian coasts. All animals possess large amounts of furanosesquiterpenoids, probably derived from their diet of sponges. The products are transferred and stored in specific sites of the mantle (mantle dermal formations, MDFs) to be used as chemical deterrents against predators. Chemical analysis of CantabrianHypselodoris species has led to the characterization of eight sesquiterpenoids. Among these, six have been found previously in both sponges and nudibranchs, while two are new natural products.Hypselodoris species cooccurring in the same area contained comparable mixtures of sesquiterpenoids. However, two populations ofH. cantabrica from different sites of the Cantabrian sea showed different metabolic patterns. All sesquiterpenoids induce feeding deterrence inCarassius auratus and two are also toxic toGambusia affinis.  相似文献   
10.
A 5-layer passive organic dermal sampler was developed to allow the collection, retention, and recovery of a variety of organic compound classes simultaneously. The 5-layers, from outside in, consisted of polypropylene, polyurethane foam, C-18 solid-phase extraction disk, ethylene tetrafluoroethylene, and activated carbon cloth. The layers were enclosed in aluminum foil and placed in a muslin envelope that had a 40.0 mm diameter opening.

Ten samplers were spiked separately with three levels of diesel oil, a 50/50 diesel oil/asphalt mixture, and asphalt binder. For the diesel oil spikes, recoveries were 69.9, 71.3, 88.8, and 95.4% for 10, 10, 50, and 100 mg of diesel oil. For the 50/50 mixture, recoveries were 105.4, 92.8, and 92.0% for 10, 50, and 100 mg of the 50/50 mixture. For the asphalt binder spikes, recoveries were 104.7, 100.2, and 100.1% for 10, 50, and 100 mg of asphalt binder. For repeatability assessment, 7 samplers were spiked with 50 mg of the 50/50 mixture and recoveries averaged 92.6% (standard deviation 8.6). Samplers tested on asphalt paving workers proved functional, comfortable, flexible, and durable.  相似文献   
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