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51.
The exposure to either medical sources or accidental radiation can cause varying degrees of radiation injury (RI). RI is a common disease involving multiple human body parts and organs, yet effective treatments are currently limited. Accumulating evidence suggests gut microbiota are closely associated with the development and prevention of various RI. This article summarizes 10 common types of RI and their possible mechanisms. It also highlights the changes and potential microbiota-based treatments for RI, including probiotics, metabolites, and microbiota transplantation. Additionally, a 5P-Framework is proposed to provide a comprehensive strategy for managing RI. 相似文献
52.
Zikai Zheng Jiaming Li Tianzi Liu Yanling Fan Qiao-Cheng Zhai Muzhao Xiong Qiao-Ran Wang Xiaoyan Sun Qi-Wen Zheng Shanshan Che Beier Jiang Quan Zheng Cui Wang Lixiao Liu Jiale Ping Si Wang Dan-Dan Gao Jinlin Ye Kuan Yang Yuesheng Zuo Shuai Ma Yun-Gui Yang Jing Qu Feng Zhang Peilin Jia Guang-Hui Liu Weiqi Zhang 《蛋白质与细胞》2024,15(8):575-593
Epigenetic clocks are accurate predictors of human chronological age based on the analysis of DNA methylation (DNAm) at specific CpG sites. However, a systematic comparison between DNA methylation data and other omics datasets has not yet been performed. Moreover, available DNAm age predictors are based on datasets with limited ethnic representation. To address these knowledge gaps, we generated and analyzed DNA methylation datasets from two independent Chinese cohorts, revealing age-related DNAm changes. Additionally, a DNA methylation aging clock (iCAS-DNAmAge) and a group of DNAm-based multi-modal clocks for Chinese individuals were developed, with most of them demonstrating strong predictive capabilities for chronological age. The clocks were further employed to predict factors influencing aging rates. The DNAm aging clock, derived from multi-modal aging features (compositeAge-DNAmAge), exhibited a close association with multi-omics changes, lifestyles, and disease status, underscoring its robust potential for precise biological age assessment. Our findings offer novel insights into the regulatory mechanism of age-related DNAm changes and extend the application of the DNAm clock for measuring biological age and aging pace, providing the basis for evaluating aging intervention strategies. 相似文献
53.
Chen Dai;Jia-Xin Tian;Yu-Feng Chen;Yue-Han Ni;Lei Cui;Hai-Xing Cao;Lin-Lin Song;Shen-Yuan Xu;Ya-Jun Wang;Yu-Guo Zheng; 《Biotechnology journal》2024,19(3):2300637
The aldo-keto reductase (AKR) KdAKR from Kluyvermyces dobzhanskii can reduce t-butyl 6-chloro-(5S)-hydroxy-3-oxohexanoate ((5S)-CHOH) to t-butyl 6-chloro-(3R,5S)-dihydroxyhexanoate ((3R,5S)-CDHH), which is the key chiral intermediate of rosuvastatin. Herein, a computer-aided design that combined the use of PROSS platform and consensus design was employed to improve the stability of a previously constructed mutant KdAKRM6. Experimental verification revealed that S196C, T232A, V264I and V45L produced improved thermostability and activity. The “best” mutant KdAKRM10 (KdAKRM6-S196C/T232A/V264I/V45L) was constructed by combining the four beneficial mutations, which displayed enhanced thermostability. Its T5015 and Tm values were increased by 10.2 and 10.0°C, respectively, and half-life (t1/2) at 40°C was increased by 17.6 h. Additionally, KdAKRM10 demonstrated improved resistance to organic solvents compared to that of KdAKRM6. Structural analysis revealed that the increased number of hydrogen bonds and stabilized hydrophobic core contributed to the rigidity of KdAKRM10, thus improving its stability. The results validated the feasibility of the computer-aided design strategy in improving the stability of AKRs. 相似文献
54.
Xinmei Kang Huaxin Chen Zhuowei Zhou Silin Tu Bo Cui Yanli Li Shuai Dong Qi Zhang Yan Xu 《Advanced Biosystems》2024,8(3):2300403
Liver fibrosis is the integral process of chronic liver diseases caused by multiple etiologies and characterized by excessive deposition of extracellular matrix (ECM). During liver fibrosis, hepatic stellate cells (HSCs) transform into a highly proliferative, activated state, producing various cytokines, chemokines, and ECM. However, the precise mechanisms that license HSCs into the highly proliferative state remain unclear. Cyclin-dependent kinase 1 (CDK1) is a requisite event for the transition of the G1/S and G2/M phases in eukaryotic cells. In this study, it is demonstrated that CDK1 and its activating partners, Cyclin A2 and Cyclin B1, are upregulated in both liver fibrosis/cirrhosis patient specimens and the murine hepatic fibrosis models, especially in activated HSCs. In vitro, CDK1 is upregulated in spontaneously activated HSCs, and inhibiting CDK1 with specific small-molecule inhibitors (CGP74514A, RO-3306, or Purvalanol A) orshort hairpin RNAs (shRNAs) resulted in HSC apoptosis and cell cycle arrest by regulating Survivin expression. Above all, it is illustrated that increased CDK1 expression licenses the HSCs into a highly proliferative state and can serve as a potential therapeutic target in liver fibrosis. 相似文献
55.
在全球气候变化的影响下, 干旱和半干旱地区的降水格局呈现出降雨强度增加、降雨频率减少但降雨总量不变的趋势。大气氮沉降作为另一个全球气候变化的重要因子, 沉降速率逐年加剧, 显著影响生态功能及过程。线虫是陆地生态系统中最主要的土壤生物, 参与多种地下生态过程。线虫群落的多样性尤其是功能、系统发育多样性如何对降水格局的改变做出响应, 以及氮沉降如何调节这些响应, 目前仍不清楚。本研究利用中国科学院植物研究所多伦恢复生态学试验研究站长期模拟降水格局改变及氮沉降添加试验平台, 开展了5个降雨强度(2 mm、5 mm、10 mm、20 mm、40 mm)处理和氮添加(10 g N·m-2·yr-1)对土壤线虫分类、功能和系统发育多样性的影响研究。结果表明, 降水强度较强但频率较低可以提高线虫的分类α多样性、功能α多样性、系统发育α多样性; 同时降低了分类β多样性和系统发育β多样性。然而, 氮添加降低了中高强度降水处理下线虫的分类α多样性、功能α多样性、系统发育α多样性, 同时提高了分类β多样性、功能β多样性和系统发育β多样性。土壤含水量和土壤微生物量碳含量是影响线虫功能及系统发育多样性的主要因素。本研究结果表明, 由于全球气候变化, 未来几十年降雨强度的增加可能有利于干旱和半干旱生态系统中的土壤线虫功能多样性和系统发育多样性。然而, 在氮沉降严重的地区, 这种正效应可能会被氮沉降导致的土壤环境的恶化所抵消。 相似文献
56.
Chunqiao Zhao Yuesen Yue Qiang Guo Juying Wu Jinku Song Qinghai Wang Cui Li Yang Hu Sisi Wang Ning Yuan Zhengang Wang Ranran Fan Xincun Hou Xifeng Fan 《Global Change Biology Bioenergy》2023,15(9):1105-1118
Miscanthus spp. show excellent application prospects due to its bioenergy potential and multiple ecological services. Annual N export with biomass harvest from Miscanthus, even without fertilizer supplement, do not reduce soil N levels. The question arises regarding how Miscanthus can maintain stable soil N levels. Metagenomic strategies were used to reveal soil N-cycling-related microbiome and their functional contributions to processes of soil N-cycling based on the comparison among the bare land, cropland, 10-year Miscanthus × giganteus, and 15-year Miscanthus sacchariflorus fields. The results showed that, after long-term cropland-to-Miscanthus conversion (LCMC), 16 of 21 bacterial phyla and all the archaeal phyla exhibited significant changes. Soil microbial denitrification and nitrification functions were significantly weakened, and N fixation (NF) was significantly enhanced. The biosynthesis of amino acids, especially alanine, aspartate, and glutamate metabolism, in soil N-cycling-related microbiome was dramatically promoted. The genus Anaeromyxobacter contributed largely to the NF process after LCMC. Variations in the soil available potassium, available N, organic C, and total N contents drove a functional shift of soil microbiome from cropland to Miscanthus pattern. We conclude that Miscanthus can recruit Anaeromyxobacter communities to enhance NF benefiting its biomass sustainability and soil N balance. 相似文献
57.
Santiago Tijaro-Bulla Samuel Protais Nyandwi Haissi Cui 《Wiley interdisciplinary reviews. RNA》2023,14(5):e1789
Aminoacyl-tRNA synthetases form the protein family that controls the interpretation of the genetic code, with tRNA aminoacylation being the key chemical step during which an amino acid is assigned to a corresponding sequence of nucleic acids. In consequence, aminoacyl-tRNA synthetases have been studied in their physiological context, in disease states, and as tools for synthetic biology to enable the expansion of the genetic code. Here, we review the fundamentals of aminoacyl-tRNA synthetase biology and classification, with a focus on mammalian cytoplasmic enzymes. We compile evidence that the localization of aminoacyl-tRNA synthetases can be critical in health and disease. In addition, we discuss evidence from synthetic biology which made use of the importance of subcellular localization for efficient manipulation of the protein synthesis machinery. This article is categorized under:
- RNA Processing
- Translation > Translation Regulation
- RNA Processing > tRNA Processing
- RNA Export and Localization > RNA Localization
58.
Zhang Heng Ren Ning-tao Zhou Fang-qiang Li Jie Lei Wei Liu Ning Bi Long Wu Zi-xiang Zhang Ran Zhang Yong-gang Cui Geng 《Neurochemical research》2016,41(9):2433-2442
With the development of technology and space exploration, studies on long-duration space flights have shown that microgravity induces damage to multiple organs, including the dorsal root ganglia (DRG). However, very little is known about the effects of long-term microgravity on DRG neurons. This study investigated the effects of microgravity on lumbar 5 (L5) DRG neurons in rats using the hindlimb unweighting (HU) model. Male (M) and female (F) Sprague-Dawley rats were randomly divided into M- and F-control (CON) groups and M- and F-HU groups, respectively (n = 10). At the end of HU treatment for 4 weeks, morphological changes were detected. Myelin basic protein (MBP) and degenerated myelin basic protein (dgen-MBP) expressions were analyzed by immunofluorescence and western blot assays. Glial cell line-derived neurotrophic factor (GDNF) protein and mRNA expressions were also analyzed by immunohistochemistry, western blot, and RT-PCR analysis, respectively. Compared with the corresponding CON groups, the HU groups exhibited slightly loose junctions between DRG neurons, some separated ganglion cells and satellite cells, and lightly stained Nissl bodies that were of smaller size and had a scattered distribution. High levels of dgen-MBP and low MBP expressions were appeared and GDNF expressions were significantly decreased in both HU groups. Changes were more pronounced in the F-HU group than in the M-HU group. In conclusion, HU treatment induced damage of L5 DRG neurons, which was correlated with decreased total MBP protein expression, increased dgen-MBP expression, and reduced GDNF protein and mRNA expression. Importantly, these changes were more severe in F-HU rats compared with M-HU rats.
相似文献59.
60.
Guofa Cai Peter Darmawan Mengqi Cui Jiangxin Wang Jingwei Chen Shlomo Magdassi Pooi See Lee 《Liver Transplantation》2016,6(4)
Silver grids are attractive for replacing indium tin oxide as flexible transparent conductors. This work aims to improve the electrochemical stability of silver‐based transparent conductors. A silver grid/PEDOT:PSS hybrid film with high conductivity and excellent stability is successfully fabricated. Its functionality for flexible electrochromic applications is demonstrated by coating one layer of WO3 nanoparticles on the silver grid/PEDOT:PSS hybrid film. This hybrid structure presents a large optical modulation of 81.9% at 633 nm, fast switching, and high coloration efficiency (124.5 cm2 C?1). More importantly, an excellent electrochemical cycling stability (sustaining 79.1% of their initial transmittance modulation after 1000 cycles) and remarkable mechanical flexibility (optical modulation decay of only 7.5% after 1200 compressive bending cycles) is achieved. A novel smart supercapacitor is presented that functions as a regular energy‐storage device and simultaneously monitors the level of stored energy by a rapid and reversible color variation even at high current charge/discharge conditions. The film sustains an optical modulation of 87.7% and a specific capacitance of 67.2% at 10 A g?1 compared to their initial value at a current density of 1 A g?1. The high‐performance silver grid/PEDOT:PSS hybrid transparent films exhibit promising features for various emerging flexible electronics and optoelectronic devices. 相似文献