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131.
聚多巴胺作为贻贝的仿生材料,可由多巴胺在碱性环境中自发形成。由于其较好的黏附特性以及组织相容性,在生命科学等领域有着广泛的应用。将聚多巴胺对材料进行表面修饰,既可以保护材料免受强氧化剂、酸碱等外界的侵蚀,也可以通过表面改性赋予材料新的功能,使其在各领域发挥更好的作用。对聚多巴胺的制备原理、生物性能,以及近年来在组织工程领域(骨组织、软骨组织、硬脑膜组织、血管组织、耳组织)的运用进行综述,以期为后续聚多巴胺作为组织工程黏附材料的研究提供参考。 相似文献
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Yuyu Li Yuxin Zhang Jianrong Lu Yong Yin Jun Xie Biao Xu 《Journal of cellular and molecular medicine》2021,25(17):8087-8094
Inflammatory responses play a vital role in the onset and development of atherosclerosis, and throughout the entire process of the chronic disease. The inflammatory responses in atherosclerosis are mainly mediated by the NLRP3 inflammasome and its downstream inflammatory factors. As a powerful anti-inflammatory medicine, colchicine has a history of more than 200 years in clinical application and is the first-choice treatment for immune diseases such as gout and familial Mediterranean fever. In atherosclerosis, colchicine can inhibit the assembly and activation of NLRP3 inflammasome via various mechanisms to effectively reduce the expression of inflammatory factors, thereby reducing the inflammation. Recent clinical trials show that a low dose of colchicine (0.5 mg per day) has a certain protective effect in stable angina patients or those with acute myocardial infarction after PCI. This article summarizes and discusses the mechanisms of colchicine in the treatment of atherosclerosis and the latest research progress. 相似文献
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Wei Liu Chunyu Wang Shengli Wang Kai Zeng Shan Wei Ning Sun Ge Sun Manlin Wang Renlong Zou Wensu Liu Lin Lin Huijuan Song Zining Jin Yue Zhao 《International journal of biological sciences》2021,17(1):188
Androgen receptor (AR) and its variants play vital roles in development and progression of prostate cancer. To clarify the mechanisms involved in the enhancement of their actions would be crucial for understanding the process in prostate cancer and castration-resistant prostate cancer transformation. Here, we provided the evidence to show that pre-mRNA processing factor 6 (PRPF6) acts as a key regulator for action of both AR full length (AR-FL) and AR variant 7 (AR-V7), thereby participating in the enhancement of AR-FL and AR-V7-induced transactivation in prostate cancer. In addition, PRPF6 is recruited to cis-regulatory elements in AR target genes and associates with JMJD1A to enhance AR-induced transactivation. PRPF6 also promotes expression of AR-FL and AR-V7. Moreover, PRPF6 depletion reduces tumor growth in prostate cancer-derived cell lines and results in significant suppression of xenograft tumors even under castration condition in mouse model. Furthermore, PRPF6 is obviously highly expressed in human prostate cancer samples. Collectively, our results suggest PRPF6 is involved in enhancement of oncogenic AR signaling, which support a previously unknown role of PRPF6 during progression of prostate cancer and castration-resistant prostate cancers. 相似文献
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Yihao Ge Chengxing Xia Jun Wang Xiujie Zhang Xufa Ma Qiong Zhou 《Ecology and evolution》2021,11(10):5669
Macroinvertebrates have been recognized as key ecological indicators of aquatic environment and are the most commonly used approaches for water quality assessment. However, species identification of macroinvertebrates (especially of aquatic insects) proves to be very difficult due to the lack of taxonomic expertise in some regions and can become time‐consuming. In this study, we evaluated the feasibility of DNA barcoding for the classification of benthic macroinvertebrates and investigated the genetic differentiation in seven orders (Insecta: Ephemeroptera, Plecoptera, Trichoptera, Diptera, Hemiptera, Coleoptera, and Odonata) from four large transboundary rivers of northwest China and further explored its potential application to biodiversity assessment. A total of 1,144 COI sequences, belonging to 176 species, 112 genera, and 53 families were obtained and analyzed. The barcoding gap analysis showed that COI gene fragment yielded significant intra‐ and interspecific divergences and obvious barcoding gaps. NJ phylogenetic trees showed that all species group into monophyletic species clusters whether from the same population or not, except two species (Polypedilum. laetum and Polypedilum. bullum). The distance‐based (ABGD) and tree‐based (PTP and MPTP) methods were utilized for grouping specimens into Operational Taxonomic Units (OTUs) and delimiting species. The ABGD, PTP, and MPTP analysis were divided into 177 (p = .0599), 197, and 195 OTUs, respectively. The BIN analysis generated 186 different BINs. Overall, our study showed that DNA barcoding offers an effective framework for macroinvertebrate species identification and sheds new light on the biodiversity assessment of local macroinvertebrates. Also, the construction of DNA barcode reference library of benthic macroinvertebrates in Eurasian transboundary rivers provides a solid backup for bioassessment studies of freshwater habitats using modern high‐throughput technologies in the near future. 相似文献
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The purpose of this study was to determine mitochondrial changes in fast muscles from interleukin-15 receptor alpha knockout (IL-15RαKO) mice. We tested the hypothesis that fast muscles from IL-15RαKO mice would have a greater mitochondrial density and altered internal structure compared to muscles from control mice. In fast muscles from IL-15RαKO mice, mitochondrial density was 48% greater with a corresponding increase in mitochondrial DNA content. Although there were no differences in the relative size of isolated mitochondria, internal complexity was lower in mitochondria from IL-15RαKO mice. These data support an increase in mitochondrial biogenesis and provide direct evidence for a greater density and altered internal structure of mitochondria in EDL muscles deficient in IL-15Rα. 相似文献
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