240 research outputs found
Inhibition of nuclear factor-κB by 6-O-acetyl shanzhiside methyl ester protects brain against injury in a rat model of ischemia and reperfusion
<p>Abstract</p> <p>Background</p> <p>Recent studies have demonstrated an inflammatory response associated with the pathophysiology of cerebral ischemia. The beneficial effects of anti-inflammatory drugs in cerebral ischemia have been documented. When screening natural compounds for drug candidates in this category, we isolated 6-O-acetyl shanzhiside methyl ester (ND02), an iridoid glucoside compound, from the leaves of <it>Lamiophlomis rotata (Benth.) Kudo</it>. The objectives of this study were to determine the effects of ND02 on a cultured neuronal cell line, SH-SY5Y, in vitro, and on experimental ischemic stroke in vivo.</p> <p>Methods</p> <p>For TNF-α-stimulated SH-SY5Y cell line experiments in vitro, SH-SY5Y cells were pre-incubated with ND02 (20 μM or 40 μM) for 30 min and then incubated with TNF-α (20 ng/ml) for 15 min. For in vivo experiments, rats were subjected to middle cerebral artery occlusion (MCAO) for 1 h followed by reperfusion for 23 h.</p> <p>Results</p> <p>ND02 treatment of SH-SY5Y cell lines blocked TNF-α-induced nuclear factor-κB (NF-κB) and IκB-α phosphorylation and increased Akt phosphorylation. LY294002 blocked TNF-α-induced phosphorylation of Akt and reduced the phosphorylation of both IκB-α and NF-κB. At doses higher than 10 mg/kg, ND02 had a significant neuroprotective effect in rats with cerebral ischemia and reperfusion (I/R). ND02 (25 mg/kg) demonstrated significant neuroprotective activity even after delayed administration 1 h, 3 h and 5 h after I/R. ND02, 25 mg/kg, attenuated histopathological damage, decreased cerebral Evans blue extravasation, inhibited NF-κB activation, and enhanced Akt phosphorylation.</p> <p>Conclusion</p> <p>These data show that ND02 protects brain against I/R injury with a favorable therapeutic time-window by alleviating cerebral I/R injury and attenuating blood-brain barrier (BBB) breakdown, and that these protective effects may be due to blocking of neuronal inflammatory cascades through an Akt-dependent NF-κB signaling pathway.</p
Combustion synthesis of Ce2LuO5.5:Eu phosphor nanopowders: structure, surface and luminescence investigations
The spherical shape, uniform size and small degree of agglomeration of the particles play crucial roles in promoting the practical applications of the phosphor powders. In this paper, the novel Eu3+ -doped cerium lutetium Ce2LuO5.5 composite nanopowders with a cubic fluorite structure were prepared via a typical solution combustion route, and their internal structure, surface morphology as well as luminescence properties were investigated. The Eu3+ could substitute in either Lu3+ or Ce4+ sites and the existence of oxygen vacancy was confirmed in the composite by X-ray diffraction and Raman spectra techniques. Without the addition of surfactant, most of the as-prepared particles were bound together, and the luminescence was very weak even after a sintering process. Assisted with appropriate polyvinyl alcohol (PVA) surfactant in the combustion reaction and a subsequent heat-treatment process, the bound-particles were evidently separated and seemed to be nearly spherical shape. The particle size could be controlled to 30–120 nm and the luminescence was enhanced by adjusting the subsequent sintering temperature. Excited with 466 nm blue light, the nanopowders exhibited characteristic 5D0 → 7FJ (J = 0–4) emission transition of Eu3+ and showed enhanced red luminescence as Eu3+ occupied Ce4+ site rather than Lu3+ site. The maximum emission was obtained as 40 mol% Eu substitutes Ce in the composite. Due to the coincidence of 466 nm excitation light with the emission of InGaN chips in white light-emitting diodes, the surface-morphology improved Eu-doped Ce2LuO5.5 phosphor nanopowders have a potential application in solid state lighting fields.publishe
Ln3+ (Ln = Eu, Dy) - doped Sr2CeO4 fine phosphor particles: wet chemical preparation, energy transfer and tunable luminescence
The Sr2CeO4:Ln3+ (Ln = Eu, Dy) fine phosphor particles were prepared by a facile wet chemical approach, in which the consecutive hydrothermal-combustion reaction was performed. The doping of Ln3+ into Sr2CeO4 has little influence on the structure of host, and the as-prepared samples display well-crystallized spherical or elliptical shape with an average particle size at about 100–200 nm. For Eu3+ ions-doped Sr2CeO4, with the increase of Eu3+-doping concentration, the blue light emission band with the maximum at 468 nm originating from a Ce4+ → O2− charge transfer of the host decreases obviously and the characteristic red light emission of Eu3+ (5D0→7F2 transition at 618 nm) is enhanced gradually. Simultaneously, the fluorescent lifetime of the broadband emission of Sr2CeO4 decreases with the doping of Eu3+, indicating an efficient energy transfer from the host to the doping Eu3+ ions. The energy transfer efficiency from the host to Eu3+ was investigated in detail, and the emitting color of Sr2CeO4:Eu3+ can be easily tuned from blue to red by varying the doping concentration of Eu3+ ions. Moreover, the luminescence of Dy3+-doped Sr2CeO4 was also studied. Similar energy transfer phenomenon can be observed, and the incorporation of Dy3+ into Sr2CeO4 host leads to the characteristic emission of 4F9/2 → 6H15/2 (488 nm, blue light) and 4F9/2 → 6H13/2 (574 nm, yellow light) of Dy3+. The Sr2CeO4:Ln3+ fine particles with tunable luminescence are quite beneficial for its potential applications in the optoelectronic fields.publishe
Lithium storage in a highly conductive Cu<sub>3</sub>Ge boosted Ge/graphene aerogel
A Cu3Ge/Ge@G aerogel was synthesized via a simple pyrolysis route and directly employed as a high performance anode for lithium-ion batteries.</p
Quantitative DNA Methylation Analysis of DLGAP2 Gene Using Pyrosequencing in Schizophrenia With Tardive Dyskinesia: A Linear Mixed Model Approach
Tardive dyskinesia (TD) is a side effect of antipsychotic medications used to treat schizophrenia (SCZ) and other mental health disorders. No study has previously used pyrosequencing to quantify DNA methylation levels of the DLGAP2 gene; while the quantitative methylation levels among CpG sites within a gene may be correlated. To deal with the correlated measures among three CpG sites within the DLGAP2 gene, this study analyzed DNA methylation levels of the DLGAP2 gene using a linear mixed model (LMM) in a Chinese sample consisting of 35 SCZ patients with TD, 35 SCZ without TD (NTD) and 34 healthy controls (HCs) collected in Beijing, China. The initial analysis using the non-parametric Kruskal-Wallis test revealed that three groups (TD, NTD and HC) had significant differences in DNA methylation level for CpG site 2 (p = 0.0119). Furthermore, the average methylation levels among the three CpG sites showed strong correlations (all p values \u3c 0.0001). In addition, using the LMM, three groups had significant differences in methylation level (p = 0.0027); while TD, NTD and TD + NTD groups showed higher average methylation levels than the HC group (p = 0.0024, 0.0151, and 0.0007, respectively). In conclusion, the LMM can accommodate a covariance structure. The findings of this study provide first evidence of DNA methylation levels in DLGAP2 associated with SCZ with TD in Chinese population. However, TD just showed borderline significant differences to NTD in this study
Active YAP promotes pancreatic cancer cell motility, invasion and tumorigenesis in a mitotic phosphorylation-dependent manner through LPAR3.
The transcriptional co-activator Yes-associated protein, YAP, is a main effector in the Hippo tumor suppressor pathway. We recently defined a mechanism for positive regulation of YAP through CDK1-mediated mitotic phosphorylation. Here, we show that active YAP promotes pancreatic cancer cell migration, invasion and anchorage-independent growth in a mitotic phosphorylation-dependent manner. Mitotic phosphorylation is essential for YAP-driven tumorigenesis in animals. YAP reduction significantly impairs cell migration and invasion. Immunohistochemistry shows significant upregulation and nuclear localization of YAP in metastases when compared with primary tumors and normal tissue in human. Mitotic phosphorylation of YAP controls a unique transcriptional program in pancreatic cells. Expression profiles reveal LPAR3 (lysophosphatidic acid receptor 3) as a mediator for mitotic phosphorylation-driven pancreatic cell motility and invasion. Together, this work identifies YAP as a novel regulator of pancreatic cancer cell motility, invasion and metastasis, and as a potential therapeutic target for invasive pancreatic cancer
Molecular classification and fertility-sparing outcomes in endometrial cancer and atypical endometrial hyperplasia
Molecular classification has emerged as a critical tool for guiding personalized treatment in endometrial cancer (EC) and atypical endometrial hyperplasia (AEH). This retrospective study aimed to assess the impact of molecular classification on fertility-sparing treatment outcomes in patients diagnosed with EC and AEH who underwent fertility preservation therapy between 2006 and 2021. Patients were categorized into four molecular subtypes using immunohistochemistry (IHC) and Sanger sequencing, based on the Proactive Molecular Risk Classifier for Endometrial Cancer (ProMisE): POLE-ultramutated, mismatch repair (MMR) deficient (MMRd), p53 abnormal (p53abn), and p53 wild-type (p53wt). All patients were evaluated for oncological prognosis and fertility outcomes, with a total of 103 patients included in the analysis. Recurrence rates exhibited significant differences among the molecular classifications, with the lowest recurrence rate observed in the p53wt subtype (19.7%), followed by MMRd (30.4%), POLE-ultramutated (66.7%), and p53abn (71.4%) subtypes. Multivariate Cox regression analysis indicated that the p53abn subtype was a significant risk factor for recurrence following conservation therapy when compared to the p53wt subtype. Additionally, there was a notable disparity in standard surgical treatment due to treatment failure, with operation rates of 7.5%, 19.2%, 66.7%, and 57.1% for the p53wt, MMRd, POLE-ultramutated, and p53abn subtypes, respectively. Regarding fertility outcomes, the p53wt group demonstrated the highest pregnancy rate after achieving a complete response compared to the other subtypes; however, no significant differences were observed in overall pregnancy outcomes. The ProMisE molecular classification holds significant prognostic value for patients with EC and AEH undergoing fertility-sparing treatment. Among the molecular subtypes, p53wt appears to be the most favorable for fertility-preserving interventions. This study provides essential insights into reproductive outcomes for this patient population
Hydrothermal catalytic production of fuels and chemicals from aquatic biomass
One of the promising avenues for biomass processing is the use of water as a reaction medium for wet or aquatic biomass. This review focuses on the hydrothermal catalytic production of fuels and chemicals from aquatic biomass. Two different regimes for conversion of aquatic biomass in hydrothermal conditions are discussed in detail. The first is hydrothermal liquefaction, and the second is hydrothermal gasification. The goals of these processes are to produce liquid‐fuel‐range hydrocarbons and methane or hydrogen, respectively. The catalytic upgrading of biocrude resulting from noncatalytic liquefaction and the stability and degradation of catalysts in high temperature water are also discussed. The review concludes with a brief discussion of the outlook for and opportunities within the field of hydrothermal catalytic valorization of biomass. Copyright © 2012 Society of Chemical IndustryPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94889/1/jctb3933.pd
Bioinformatics and systems biology approach to identify the pathogenetic link of neurological pain and major depressive disorder
Neurological pain (NP) is always accompanied by symptoms of depression, which seriously affects physical and mental health. In this study, we identified the common hub genes (Co-hub genes) and related immune cells of NP and major depressive disorder (MDD) to determine whether they have common pathological and molecular mechanisms. NP and MDD expression data was downloaded from the Gene Expression Omnibus (GEO) database. Common differentially expressed genes (Co-DEGs) for NP and MDD were extracted and the hub genes and hub nodes were mined. Co-DEGs, hub genes, and hub nodes were analyzed for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment. Finally, the hub nodes, and genes were analyzed to obtain Co-hub genes. We plotted Receiver operating characteristic (ROC) curves to evaluate the diagnostic impact of the Co-hub genes on MDD and NP. We also identified the immune-infiltrating cell component by ssGSEA and analyzed the relationship. For the GO and KEGG enrichment analyses, 93 Co-DEGs were associated with biological processes (BP), such as fibrinolysis, cell composition (CC), such as tertiary granules, and pathways, such as complement, and coagulation cascades. A differential gene expression analysis revealed significant differences between the Co-hub genes ANGPT2, MMP9, PLAU, and TIMP2. There was some accuracy in the diagnosis of NP based on the expression of ANGPT2 and MMP9. Analysis of differences in the immune cell components indicated an abundance of activated dendritic cells, effector memory CD8+ T cells, memory B cells, and regulatory T cells in both groups, which were statistically significant. In summary, we identified 6 Co-hub genes and 4 immune cell types related to NP and MDD. Further studies are needed to determine the role of these genes and immune cells as potential diagnostic markers or therapeutic targets in NP and MDD
Caveolin-1 Plays a Crucial Role in Inhibiting Neuronal Differentiation of Neural Stem/Progenitor Cells via VEGF Signaling-Dependent Pathway
In the present study, we aim to elucidate the roles of caveolin-1(Cav-1), a 22 kDa protein in plasma membrane invaginations, in modulating neuronal differentiation of neural progenitor cells (NPCs). In the hippocampal dentate gyrus, we found that Cav-1 knockout mice revealed remarkably higher levels of vascular endothelial growth factor (VEGF) and the more abundant formation of newborn neurons than wild type mice. We then studied the potential mechanisms of Cav-1 in modulating VEGF signaling and neuronal differentiation in isolated cultured NPCs under normoxic and hypoxic conditions. Hypoxic embryonic rat NPCs were exposed to 1% O2 for 24 h and then switched to 21% O2 for 1, 3, 7 and 14 days whereas normoxic NPCs were continuously cultured with 21% O2. Compared with normoxic NPCs, hypoxic NPCs had down-regulated expression of Cav-1 and up-regulated VEGF expression and p44/42MAPK phosphorylation, and enhanced neuronal differentiation. We further studied the roles of Cav-1 in inhibiting neuronal differentiation by using Cav-1 scaffolding domain peptide and Cav-1-specific small interfering RNA. In both normoxic and hypoxic NPCs, Cav-1 peptide markedly down-regulated the expressions of VEGF and flk1, decreased the phosphorylations of p44/42MAPK, Akt and Stat3, and inhibited neuronal differentiation, whereas the knockdown of Cav-1 promoted the expression of VEGF, phosphorylations of p44/42MAPK, Akt and Stat3, and stimulated neuronal differentiation. Moreover, the enhanced phosphorylations of p44/42MAPK, Akt and Stat3, and neuronal differentiation were abolished by co-treatment of VEGF inhibitor V1. These results provide strong evidence to prove that Cav-1 can inhibit neuronal differentiation via down-regulations of VEGF, p44/42MAPK, Akt and Stat3 signaling pathways, and that VEGF signaling is a crucial target of Cav-1. The hypoxia-induced down-regulation of Cav-1 contributes to enhanced neuronal differentiation in NPCs
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