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541.
Oncogenic activation of VEGF is found in various malignancies, including ovarian cancer. In this study, we investigate the role of microRNA (miRNA) in the regulation of VEGF in ovarian cancer. We find that miR-718 is expressed at low levels and inversely correlates with VEGF expression in ovarian cancer specimens. MiR-718 also directly targets and represses VEGF expression. In addition, miR-718 restoration inhibits ovarian cancer proliferation both in vitro and in vivo. Moreover, VEGF expression could reverse the effect of miR-718 on ovarian cancer by increasing the levels of phosphorylated AKT. These results suggest a new therapeutic strategy in ovarian cancer by restoring miR-718 expression, which is involved in VEGF regulation.  相似文献   
542.
This work aimed to investigate the role and mechanism of NADPH oxidase 4 (NOX4) in the polarization of microglial cells. Microglial cells were transfected with the NOX4 overexpression plasmid (pGL3-NOX4), and later treated with lipopolysaccharide (LPS) and interferon-γ (IFN-γ) to induce its M1 polarization. Later, the F4/80 + CD86 + cell proportion was detected by flow cytometry (FCM), the inflammatory factor expression levels were analyzed through enzyme-linked immunosorbent assay (ELISA), while ionized calcium binding adapter molecule 1 (IBA-1) and PKM2 expression were measured by immunofluorescence (IF) staining. In addition, dichlorodihydrofluorescein diacetate probe was utilized to detect the reactive oxygen species (ROS) levels, glucose uptake, and glycolysis, as well as lactic acid level. The expression of glycolytic enzymes PKM2, HK2, and citrate (Si)-synthas (CS) was detected by Western-blot (WB) assay. Moreover, the polarization level of microglial cells was detected after ROS expression was suppressed by the ROS inhibitor N-acetylcysteine (NAC). In mouse experiments, LPS was applied in inducing central neuroinflammation in NOX4 knockdown mouse model (KO) and wild-type mice (WT). Thereafter, the inflammatory factor levels and lactic acid level in mouse tissues were detected; IBA-1 and CD86 expression in mice was measured by IF staining; and the expression of glycolytic enzymes PKM2, HK2, and CS in the central nervous system (CNS) was also detected. After NOX4 overexpression in microglial cells, the M1 polarization level was upregulated, the F4/80 + CD86 + cell proportion increased, and inflammatory factors were upregulated. At the same time, the expression of glycolytic enzymes PKM2, HK2, and CS was upregulated. NAC pretreatment suppressed the effects of NOX4, reduced the F4/80 + CD86 + cell proportion, and suppressed the expression of PKM2, HK2, and CS. In the mouse model, the expression levels of CD86 in KO group decreased, and the inflammatory factors were also downregulated. NOX4 promotes glycolysis of microglial cells via ROS, thus accelerating M1 polarization and inflammatory factor expression. In this regard, NOX4 is promising as a new target for the treatment of neuroinflammation.  相似文献   
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This review covers the occurrence and biological activities of all natural friedelane triterpenoids found between 1977 and March 2011. The biogeneses of dimeric friedelanes and several rearranged friedelanes are discussed. The pharmacological properties of representative compounds, including celastrol and correolide, have also been compiled, on the basis of 344 references.  相似文献   
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We reported 20 cases of discharged COVID-19 patients whose RT-PCR test results showed ‘re-positive’. After finding ‘re-positive’, these patients were admitted to hospital for the second time and were followed up until the end of May 2020. We recorded detailed treatment and follow-up process, and collected relevant data. The possible causes and potential clinical significance of this phenomenon are discussed.  相似文献   
548.
A numerical method of the left ventricle (LV) deformation, an elongation model, was put forth for the study of LV fluid mechanics in diastole. The LV elongated only along the apical axis, and the motion was controlled by the intraventricular flow rate. Two other LV models, a fixed control volume model and a dilation model, were also used for model comparison and the study of LV fluid mechanics. For clinical sphere indices (SIs, between 1.0 and 2.0), the three models showed little difference in pressure and velocity distributions along the apical axis at E-peak. The energy dissipation was lower at a larger SI in that the jet and vortex development was less limited by the LV cavity in the apical direction. LV deformation of apical elongation may represent the primary feature of LV deformation in comparison with the secondary radial expansion. The elongation model of the LV deformation with an appropriate SI is a reasonable, simple method to study LV fluid mechanics in diastole.  相似文献   
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