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991.
992.
Russian Journal of Bioorganic Chemistry - An Erratum to this paper has been published: https://doi.org/10.1134/S1068162022030074  相似文献   
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Our studies indicate that the longevity factor SIRT1 is implicated in metabolic disease; however, whether and how hepatocyte-specific SIRT1 signaling is involved in liver fibrosis remains undefined. We characterized a functional link of age-mediated defects in SIRT1 to the NLRP3 inflammasome during age-related liver fibrosis. In multiple experimental murine models of liver fibrosis, we compared the development of liver fibrosis in young and old mice, as well as in liver-specific SIRT1 knockout (SIRT1 LKO) mice and wild-type (WT) mice. Liver injury, fibrosis, and inflammation were assessed histologically and quantified by real-time PCR analysis. In a model of hepatotoxin-induced liver fibrosis, old mice displayed more severe and persistent liver fibrosis than young mice during liver injury and after injury cessation, as characterized by inhibition of SIRT1, induction of NLRP3, infiltration of macrophages and neutrophils, activation of hepatic stellate cells (HSCs), and excessive deposition and remodeling of the extracellular matrix. Mechanistically, deletion of SIRT1 in hepatocytes resulted in NLRP3 and IL-1β induction, pro-inflammatory response, and severe liver fibrosis in young mice, mimicking the ability of aging to impair the resolution of established fibrosis. In an aging mouse model, chronic-plus-binge alcohol feeding-induced liver fibrosis was attenuated by treatment with MCC950, a selective NLRP3 inhibitor. NLRP3 inhibition ameliorated alcoholic liver fibrosis in old mice by repressing inflammation and reducing hepatocyte-derived danger signaling—ASK1 and HMGB1. In conclusion, age-dependent SIRT1 defects lead to NLRP3 activation and inflammation, which in turn impairs the capacity to resolve fibrosis during aging.  相似文献   
995.
The air-stable complex [Fe(6-Me3-TPA) (O2CAr)]+ [1; 6-Me3-TPA = tris(6-methyl-2-pyridylmethyl)amine] has been synthesized as a model for the iron(II) site of lipoxygenase. This iron(II) complex reacts with 0.5 equiv ROOH to form a yellow species, which has been formulated as [FeIII(OH)(6-Me3-TPA) (O2CAr)]+ (2) by electrospray mass spectrometry. Addition of more ROOH converts 2 into a purple species, which is characterized by electrospray ionization mass spectrometry and resonance Raman spectroscopy as [FeIII(OOR)(6-Me3-TPA)(O2CAr)]+. The purple species is metastable and decomposes via Fe-O bond homolysis to regenerate the starting iron(II) complex. These metal-centered transformations parallel the changes observed for lipoxygenase in its reaction with its product hydroperoxide.  相似文献   
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高寒地区豆秸裁培香菇   总被引:2,自引:0,他引:2  
香菇在世界菇类产量中居第 2位 ,是仅次于双孢菇的食用蕈菌 ,香菇的人工栽培 ,也是我国最早 ,距今已有 80 0多年的历史。 80年代后逐渐以袋料栽培为主 ,所用原料以阔叶木屑、棉籽壳居多 ,寒地利用粉碎豆秸栽培香菇的报道甚少。黑龙江省龙门农场地处北纬 48 5°~49 0 2° ,东经 1 2 6°~ 1 2 7° ,海拔 42 5米 ,年平均气温 - 0 9℃ ,属我省第四积温带 ,是大豆主产区之一 ,随着农业产业结构调整木屑代料香菇生产已迅速发展起来 ,但林木资源的紧缺制约了香菇产业的发展 ,而这里每年大量的豆秸作为废弃物在地里堆放燃烧 ,不但是一种浪费 ,还…  相似文献   
997.
Hepatocellular carcinoma (HCC) is a heterogeneous malignancy closely related to metabolic reprogramming. We investigated how CTNNB1 mutation regulates the HCC metabolic phenotype and thus affects the prognosis of HCC. We obtained the mRNA expression profiles and clinicopathological data from The Cancer Genome Atlas (TCGA), the International Cancer Genomics Consortium (ICGC) and the Gene Expression Omnibus database ( GSE14520 and GSE116174 ). We conducted gene set enrichment analysis on HCC patients with and without mutant CTNNB1 through TCGA dataset. The Kaplan-Meier analysis and univariate Cox regression analysis assisted in screening metabolic genes related to prognosis, and the prognosis model was constructed using the Lasso and multivariate Cox regression analysis. The prognostic model showed good prediction performance in both the training cohort (TCGA) and the validation cohorts (ICGC, GSE14520 , GSE116174 ), and the high-risk group presented obviously poorer overall survival compared with low-risk group. Cox regression analysis indicated that the risk score can be used as an independent predictor for the overall survival of HCC. The immune infiltration in different risk groups was also evaluated in this study to explore underlying mechanisms. This study is also the first to describe an metabolic prognostic model associated with CTNNB1 mutations and could be implemented for determining the prognoses of individual patients in clinical practice.  相似文献   
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The study of bionics bridges the functions, biological structures and organizational principles found in nature with our modern technologies, and numerous mathematical and metaheuristic algorithms have been developed along with the knowledge transferring process from the lifeforms to the human technologies. Output of bionics study includes not only physical products, but also various computation methods that can be applied in different areas. People have learnt from biological systems and structures to design and develop a number of different kinds of optimisation algorithms that have been widely used in both theoretical study and practical applications. In this paper, a number of selected nature-inspired algorithms are systematically reviewed and analyzed. Though the paper is mainly focused on the original principle behind each of the algorithm, their applications are also discussed.  相似文献   
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