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841.
Zhu  Yuexin  Luo  Manyu  Bai  Xue  Lou  Yan  Nie  Ping  Jiang  Shan  Li  Jicui  Li  Bing  Luo  Ping 《Molecular and cellular biochemistry》2022,477(8):2073-2092
Molecular and Cellular Biochemistry - Diabetic kidney disease (DKD) is a serious microvascular complication of diabetes. Currently, the prevalence and mortality of DKD are increasing annually....  相似文献   
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The intestinal epithelium has a high rate of cell turn over and is an excellent system to study stem cell-mediated tissue homeostasis. The Misshapen subfamily of the Ste20 kinases in mammals consists of misshapen like kinase 1 (MINK1), mitogen-activated protein kinase kinase kinase kinase 4 (MAP4K4), and TRAF2 and NCK interacting kinase (TNIK). Recent reports suggest that this subfamily has a novel function equal to the Hippo/MST subfamily as upstream kinases for Warts/Large tumor suppressor kinase (LATS) to suppress tissue growth. To study the in vivo functions of Mink1, Map4k4, and Tnik, we generated a compound knockout of these three genes in the mouse intestinal epithelium. The intestinal epithelia of the mutant animals were phenotypically normal up to approximately 12 months. The older animals then exhibited mildly increased proliferation throughout the lower GI tract. We also observed that the normally spatially organized Paneth cells in the crypt base became dispersed. The expression of one of the YAP pathway target genes Sox9 was increased while other target genes including CTGF did not show a significant change. Therefore, the Misshapen and Hippo subfamilies may have highly redundant functions to regulate growth in the intestinal epithelium, as illustrated in recent tissue culture models.  相似文献   
844.
Nucleotide oligomerization domain 2(NOD2) is a major cytoplasmic sensor for pathogens and is critical for the clearance of cytosolic bacteria in mammals.However, studies regarding NOD2, especially the initiated signaling pathways, are scarce in teleost species. In this study, we identified a NOD2 molecule(PaNOD2) from ayu(Plecoglossus altivelis).Bioinformatics analysis showed the structure of NOD2 to be highly conserved during vertebrate evolution. Dual-luciferase reporter assays examined the activation of NF-κB signaling and Western blotting analysis detected the phosphorylation of three MAP kinases(p-38, Erk1/2, and JNK1/2).Functional study revealed that, like its mammalian counterparts, PaNOD2 was the receptor of the bacterial cell wall component muramyl dipeptide(MDP), and the leucine-rich repeat motif was responsible for the recognition and binding of Pa NOD2 with the ligand. Overexpression of PaNOD2 activated the NF-κB signaling pathway, leading to the upregulation of inflammatory cytokines, including TNF-α and IL-1β in HEK293 T cells and ayu head kidney-derived monocytes/macrophages(MO/MΦ).Particularly, we found that PaNOD2 activated the MAPK signaling pathways, as indicated by the increased phosphorylation of p-38, Erk1/2, and JNK1/2, which have not been characterized in any teleost species previously. Our findings proved that the NOD2 molecule and initiated pathways are conserved between mammals and ayu. Therefore, ayu could be used as an animal model to investigate NOD2-based diseases and therapeutic applications.  相似文献   
845.
The present study was to investigate the inhibitory effect of methyl helicterate (MH) on hepatic stellate cells (HSC-T6), primarily elucidating the underlying mechanism of MH against liver fibrosis. HSC-T6 cells were activated by platelet-derived growth factor (PDGF) stimulation, and then the effects of MH on cell viability, cytomembrane integrity, colony, migration, apoptosis, and cell cycle were detected. Moreover, the regulative mechanism of MH on HSCs was investigated by detecting the activation of the extracellular signal-regulated kinase (ERK1/2) signaling pathway. The results showed that MH significantly inhibited HSC-T6 cell viability and proliferation in a concentration-dependent manner. It notably promoted the release of lactate dehydrogenase, destroying cell membrane integrity. MH also markedly inhibited HSC-T6 cell clonogenicity and migration. Moreover, MH treatment significantly induced cell apoptosis and arrested cell cycle at the G2 phase. The further study showed that MH inhibited the expression of ERK1, ERK2, c-fos, c-myc, and Ets-1, blocking the ERK1/2 pathway. In conclusion, this study demonstrates that MH significantly inhibits HSC activation and promotes cell apoptosis via downregulation of the ERK1/2 signaling pathway.  相似文献   
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The diagnosis of congenital heart disease in children has been an issue in the medical community. Timely diagnosis and treatment can provide a greater guarantee for children's healthy growth. In recent years, there have been more and more studies on the diagnosis of congenital heart disease in children. This paper compares the advantages and disadvantages of echocardiography and 64-slice spiral computed tomography (CT) in the diagnosis of congenital heart disease in children. In clinical trials, we also tested 64 patients with spiral computed tomography (SCT) and transthoracic echocardiography (TTE) detection of patients and then confirmed the accuracy of the diagnosis by the surgical methods. The two methods of detection, the rate of missed diagnosis, and the rate of misdiagnosis were counted. Through the test results and pathological diagnosis results, the diagnostic accuracy of the two methods were all above 90%, each with its own advantages and disadvantages. The sensitivity of echocardiographic in detecting intracardiac structure abnormalities was relatively high, but when the diagnosis of extracardiac structural abnormalities less than 64-slice spiral CT method, misdiagnosis of TTE was mainly due to extracardiac vascular malformations. Therefore, it is recommended to combine the two methods to improve the diagnosis of congenital heart disease in children.  相似文献   
849.
Intervertebral disk degeneration (IDD) has been widely considered as one of the main causes for low back pain, which can cause a severe impact to human health and huge economic burden to worldwide society. IDD pathogenesis can be affected by extensive degradation of extracellular matrix (ECM) and the hyperproliferation of nucleus pulposus (NP) cells. During the IDD process, expression of the ECM degradation enzymes matrix metalloproteinase and ADAMTS increases, whereas expression of ECM synthesis–related aggrecan and COL2A1 decreases. In addition, the Wnt signaling pathway is reportedly involved in the process of IDD. Bu-Shen-Huo-Xue-Fang (BSHXF), a Chinese traditional medicine formula that contains six Chinese traditional medicinal herbs, is widely used in the treatment of IDD. Herein, we obtained the serum containing BSHXF from BSHXF-fed rat and demonstrated that the BSHXF promoted NP cell proliferation and ECM synthesis through the Wnt signaling pathway. By using DIANA online tools and luciferase reporter gene assays, we confirmed that miR-483-3p and miR-23c regulated CTNNB1 and GSK3B, respectively, through direct targeting, thereby affecting the effect of BSHXF on NP cell proliferation and ECM synthesis through the Wnt signaling pathway. Taken together, we demonstrated the function and mechanism of BSHXF in regulating NP cell proliferation and ECM remodeling through the Wnt signaling pathway during IDD.  相似文献   
850.
Immune-mediated quantitative and qualitative defects of hematopoietic stem/progenitor cells (HSPCs) play a vital role in the pathophysiology of acquired aplastic anemia (AA). Autophagy is closely related to T cell pathophysiology and the destiny of HSPCs, in which autophagy-related gene 5 (ATG5) is indispensably involved. We hypothesized that genetic variants of ATG5 might contribute to AA. We studied six ATG5 polymorphisms in a Chinese cohort of 176 patients with AA to compare with 157 healthy controls. A markedly decreased risk of AA in the recessive models of rs510432 and rs803360 polymorphisms (adjusted odds ratio [OR], 95% confidence interval [CI] = 0.467 [0.236-0.924], P = 0.029 for ATG5 rs510432; adjusted OR [95% CI] = 0.499 [0.255-0.975], P = 0.042 for ATG5 rs803360) was observed. Furthermore, the decreased risk was even more pronounced among nonsevere AA compared with healthy controls under recessive models (adjusted OR [95% CI] = 0.356 [0.141-0.901], P = 0.029 for ATG5 rs510432; adjusted OR [95% CI] = 0.348 [0.138-0.878], P = 0.025 for ATG5 rs803360; adjusted OR [95% CI] = 0.352 [0.139-0.891], P = 0.027 for ATG5 rs473543). Above all, rs573775 can strongly predict the occurrence of newly onset hematological event in patients with AA. Our results indicate that genetic ATG5 variants contributed to AA, which may facilitate further clarifying the underlying mechanisms of AA and making a patient-tailored medical decision.  相似文献   
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