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1.
Int J Biol Sci ; 20(5): 1563-1577, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481798

RESUMO

Fetuin-A, a hepatokine secreted by hepatocytes, binds to insulin receptors and consequently impairs the activation of the insulin signaling pathway, leading to insulin resistance. Apigenin, a flavonoid isolated from plants, has beneficial effects on insulin resistance; however, its regulatory mechanisms are not fully understood. In the present study, we investigated the molecular mechanisms underlying the protective effects of apigenin on insulin resistance. In Huh7 cells, treatment with apigenin decreased the mRNA expression of fetuin-A by decreasing reactive oxygen species-mediated casein kinase 2α (CK2α)-nuclear factor kappa-light-chain-enhancer of activated B activation; besides, apigenin decreased the levels of CK2α-dependent fetuin-A phosphorylation and thus promoted fetuin-A degradation through the autophagic pathway, resulting in a decrease in the protein levels of fetuin-A. Moreover, apigenin prevented the formation of the fetuin-A-insulin receptor (IR) complex and thereby rescued the PA-induced impairment of the insulin signaling pathway, as evidenced by increased phosphorylation of IR substrate-1 and Akt, and translocation of glucose transporter 2 from the cytosol to the plasma membrane. Similar results were observed in the liver of HFD-fed mice treated with apigenin. Collectively, our findings revealed that apigenin ameliorates obesity-induced insulin resistance in the liver by targeting fetuin-A.


Assuntos
Resistência à Insulina , Camundongos , Animais , alfa-2-Glicoproteína-HS/metabolismo , Apigenina/farmacologia , Apigenina/uso terapêutico , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Insulina/metabolismo , alfa-Fetoproteínas/metabolismo
2.
Radiol Case Rep ; 19(2): 825-830, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38111550

RESUMO

This study presents a rare case of an older woman with an intracranial mesenchymal tumor in the right frontal and parietal lobes. Despite prompt surgical intervention, her condition rapidly deteriorated because of tumor dissemination, leading to her demise. We highlight the tumor's marked invasiveness and heterogeneity, coupled with a propensity for distant systemic metastasis, which negatively impacted the patient's prognosis. This particular clinical behavior had not been previously reported, making this a novel observation. Thus, through a comprehensive review of relevant literature, we aim to provide valuable insights for further understanding, diagnosing, and treating such tumors.

3.
Micromachines (Basel) ; 13(11)2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36363881

RESUMO

The decoupled-plasma nitridation treatment process is an effective recipe for repairing the trap issues when depositing high-k gate dielectric. Because of this effect, electrical performance is not only increased with the relative dielectric constant, but there is also a reduction in gate leakage. In the past, the effect of nitridation treatment on channel-length was revealed, but a channel-width effect with that treatment was not found. Sensing the different nano-node channel-width n-channel MOSFETs, the electrical characteristics of these test devices with nitridation treatments were studied and the relationship among them was analyzed. Based on measurement of the VT, SS, Gm, ION, and IOFF values of the tested devices, the electrical performance of them related to process treatment is improved, including the roll-off effect of channel-width devices. On the whole, the lower thermal budget in nitridation treatment shows better electrical performance for the tested channel-width devices.

4.
Gene ; 735: 144277, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-31821872

RESUMO

Cerebral ischemia injury is common in cerebral ischemic disease, and treatment options remain limited. Krueppel-like factor 2 (KLF2) is reported to negatively regulate inflammation in several ischemic diseases. Our study aimed to investigate the effects and underlying mechanism of KLF2 in BV2 microglial cells exposed to oxygen and glucose deprivation (OGD). We first found decreased KLF2 and toll-like receptor 2 (TLR2)/TLR4 in these cells. OGD also led to decrease in cell viability and increase in LDH release, apoptosis, the Bax/Bcl-2 ratio, and caspase3/9 expression, as well as production of inflammatory cytokines (e.g., TNFα, IL-1ß and IL-6), reactive oxygen species (ROS), and TLR2/TLR4. To examine KLF2's effects on these OGD effects, we infected BV2 microglial cells with an ad-KLF2 or negative control vector, and we found that KLF2 reversed all of the effects of OGD exposure. Furthermore, KLF2 significantly increased levels of BDNF and TrkB in these cells, but these effects were blocked by K252a, a BDNF/TrkB inhibitor. K252a also decreased cell viability and increased apoptosis, inflammatory factors, ROS production, and TLR2/TLR4 expression in OGD-exposed BV2 cells that were treated with KLF2, were implying that K252a could reverse the effects of KLF2 on these cells. Taken together, our study results indicate that KLF2 may protect BV2 microglial cells against OGD injury by activating the BDNF/TrkB pathway.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Glucose/deficiência , Fatores de Transcrição Kruppel-Like/metabolismo , Microglia/metabolismo , Oxigênio/metabolismo , Receptor trkB/metabolismo , Animais , Apoptose , Hipóxia Celular , Linhagem Celular , Citocinas/genética , Citocinas/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Camundongos , Transdução de Sinais , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo
5.
Nat Microbiol ; 4(2): 306-315, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30478290

RESUMO

Little is known about the specificities and neutralization breadth of the H7-reactive antibody repertoire induced by natural H7N9 infection in humans. We have isolated and characterized 73 H7-reactive monoclonal antibodies from peripheral B cells from four donors infected in 2013 and 2014. Of these, 45 antibodies were H7-specific, and 17 of these neutralized the virus, albeit with few somatic mutations in their variable domain sequences. An additional set of 28 antibodies, isolated from younger donors born after 1968, cross-reacted between H7 and H3 haemagglutinins in binding assays, and had accumulated significantly more somatic mutations, but were predominantly non-neutralizing in vitro. Crystal structures of three neutralizing and protective antibodies in complex with the H7 haemagglutinin revealed that they recognize overlapping residues surrounding the receptor-binding site of haemagglutinin. One of the antibodies, L4A-14, bound into the sialic acid binding site and made contacts with haemagglutinin residues that were conserved in the great majority of 2016-2017 H7N9 isolates. However, only 3 of the 17 neutralizing antibodies retained activity for the Yangtze River Delta lineage viruses isolated in 2016-2017 that have undergone antigenic change, which emphasizes the need for updated H7N9 vaccines.


Assuntos
Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/química , Anticorpos Antivirais/imunologia , Subtipo H7N9 do Vírus da Influenza A/imunologia , Influenza Humana/imunologia , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Neutralizantes/metabolismo , Anticorpos Antivirais/administração & dosagem , Anticorpos Antivirais/metabolismo , Sítios de Ligação , Reações Cruzadas/imunologia , Modelos Animais de Doenças , Epitopos , Feminino , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Humanos , Influenza Humana/prevenção & controle , Camundongos Endogâmicos BALB C , Conformação Proteica
6.
Biomed Pharmacother ; 107: 1705-1711, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30257388

RESUMO

Glioma is one of the most aggressive and lethal human cancers in central nervous system (CNS). Recent studies have identified many dysregulated microRNAs (miRNA, miR) in human glioma, which are a class of small non-coding RNA molecules. Increasing data have shown that miR-18a plays significant roles in several tumors. However, its effects on glioma are unclear. In this study, we found the elevated expression of c-Fos and miR-18a in tissues of human glioma patients and glioma cells. Then the miR-18a inhibitor or c-Fos siRNA were transfected into glioma cells line H4 to determine their effects on H4 cells. MTT assay showed that both miR-18a inhibitor and si-c-Fos suppressed the H4 cell proliferation. Transwell assay showed the reduced cell migration by miR-18a inhibitor and si-c-Fos in H4 cells. The increased level of H4 cells apoptosis by miR-18a inhibitor and si-c-Fos was also determined. Moreover, knockout of c-Fos decreased the miR-18a level, while miR-18a inhibitor reduced the c-Fos level in H4 cells. Added with the results of ChIP assay, this report showed a positive feedback between c-Fos and miR-18a. Finally, luciferase assay showed that HMBOX1 was directly targeted by miR-18a in H4 cells, and the HMBOX1 siRNA reversed the effects of miR-18a inhibitor on cell proliferation, migration and apoptosis of H4 cells. In conclusion, our study determine that c-Fos/miR-18a feedback loop promotes the tumor growth of gliomas by HMBOX1, providing important clues for understanding the key roles of transcription factor mediated mRNA-miRNA functional network in the regulation of gliomas.


Assuntos
Neoplasias Encefálicas/genética , Glioma/genética , Proteínas de Homeodomínio/genética , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-fos/genética , Apoptose/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Técnicas de Inativação de Genes , Glioma/patologia , Humanos , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/administração & dosagem , Transfecção , Células Tumorais Cultivadas
7.
Sensors (Basel) ; 18(9)2018 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-30149633

RESUMO

In this work, three layers of transparent conductive films of WO3/Ag/WO3 (WAW) were deposited on a glass substrate by radio frequency (RF) magnetron sputtering. The thicknesses of WO3 (around 50~60 nm) and Ag (10~20 nm) films were mainly the changeable factors to achieve the optimal transparent conductivity attempting to replace the indium tin oxide (ITO) in cost consideration. The prepared films were cardinally subjected to physical and electrical characteristic analyses by means of X-ray diffraction analysis (XRD), field-emission scanning electron microscope (FE-SEM), and Keithley 4200 semiconductor parameter analyzer. The experimental results show as the thickness of the Ag layer increases from 10 nm to 20 nm, the resistance becomes smaller. While the thickness of the WO3 layer increases from 50 nm to 60 nm, its electrical resistance becomes larger.

9.
Nanoscale Res Lett ; 7(1): 431, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22853458

RESUMO

A three-dimensional (3D) fin-shaped field-effect transistor structure based on III-V metal-oxide-semiconductor field-effect transistor (MOSFET) fabrication has been demonstrated using a submicron GaAs fin as the high-mobility channel. The fin-shaped channel has a thickness-to-width ratio (TFin/WFin) equal to 1. The nano-stacked high-k Al2O3 dielectric was adopted as a gate insulator in forming a metal-oxide-semiconductor structure to suppress gate leakage. The 3D III-V MOSFET exhibits outstanding gate controllability and shows a high Ion/Ioff ratio > 105 and a low subthreshold swing of 80 mV/decade. Compared to a conventional Schottky gate metal-semiconductor field-effect transistor or planar III-V MOSFETs, the III-V MOSFET in this work exhibits a significant performance improvement and is promising for future development of high-performance n-channel devices based on III-V materials.

10.
Nanotechnology ; 19(34): 345501, 2008 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-21730648

RESUMO

A method using gold nanoparticles (GNPs) to enhance fiber optic interferometry (GNPFOI) for immune-sensing is reported in this paper. It is suggested that an enlarged index mismatch and an elongated optical path by GNPs conjugated on recognition proteins will contribute most to signal enhancement in the interference fringe shift. Theoretical and experimental results show that the interference fringe shift is linearly related to both the amount and size of the GNPs binding on the sensor surface. The detected signal for 30 nm GNPs can reach a lowest detection limit of 18 pM (10(10) particles ml(-1)). Immune-sensing for rabbit IgG as the antigen to anti-rabbit IgG has been demonstrated and a detection cycle has been completed by elution buffer for surface regeneration. The repeatability of the immune-sensing on one GNPFOI sensor has also been verified by three identical cycles, and the detection limit for 13 nm GNPs conjugated anti-rabbit IgG reaches 0.17 nM (∼25.5 ng ml(-1)). The sensory mechanism has the potential to be engineered on the tip of a needle-type micro-device, which would allow it to monitor immune recognition signals in the future.

11.
J Cell Biochem ; 90(4): 732-44, 2003 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-14587029

RESUMO

Peroxisome proliferator-activated receptors (PPAR) are novel nuclear receptors and PPARgamma ligands have been shown to produce pro-apoptotic effects in many cancer cell types, including colon cancer. PPARgamma ligands exert their effect through PPARgamma-dependent (genomic) and PPARgamma-independent (non-genomic) mechanisms. Recent evidence suggests that PPARgamma ligands exert their pro-apoptotic effects in part by directly antagonizing the NF-kappabeta pathway as well as through activation of the MAP kinase pathway. In this report, we have demonstrated that ciglitazone, a member of the thiazoldinedione class of PPARgamma ligands induces HT-29 colon cancer cells to undergo apoptosis and prior to apoptosis, ciglitazone exposure results in a transient phosphorylation of PPARgamma. This phosphorylation of PPARgamma was mediated through the ciglitazone-induced activation of Erk1/2. PPARgamma phosphorylation affected the genomic pathway by being inhibitory to PPARgamma-DNA binding and PPRE transcriptional activity, as well as the non-genomic pathway by increasing the physical interaction of PPARgamma with p65, leading to the inhibition of NF-kappabeta. Ciglitazone induced phosphorylation of PPARgamma through the MAP kinase pathway provides a potential regulatory mechanism for PPARgamma's physical interaction with p65, leading to inhibition of NF-kappabeta and subsequent apoptosis.


Assuntos
Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , DNA/genética , DNA/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Sistema de Sinalização das MAP Quinases , Proteína Quinase 3 Ativada por Mitógeno , NF-kappa B/química , Fosforilação/efeitos dos fármacos , Ligação Proteica , Receptores Citoplasmáticos e Nucleares/genética , Tiazolidinedionas/farmacologia , Fator de Transcrição RelA , Fatores de Transcrição/genética
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