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1.
Opt Lett ; 49(10): 2801-2804, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748165

RESUMO

We propose a non-uniform-quantization digital-analog radio-over-fiber (NUQ-DA-RoF) scheme based on an advanced K-means NUQ algorithm and demonstrate it experimentally in a 2-m 300-GHz photonics-aided wireless fronthaul system. Results show that the NUQ-DA-RoF scheme achieves a SNR gain of ∼1.9 dB compared to the uniform-quantization DA-RoF (UQ-DA-RoF) at an equivalent Common Public Radio Interface equivalent data rate (CPRI-EDR). Remarkably, the NUQ-DA-RoF scheme exhibits an ∼1.6-dB power sensitivity enhancement over the UQ-DA-RoF at the 256-QAM SNR threshold. These findings highlight the advantages of the NUQ-DA-RoF scheme over UQ-DA-RoF in terms of power budget and SNR improvement, suggesting promising prospects for future radio access networks and wireless fronthaul.

2.
Molecules ; 29(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731488

RESUMO

This study synthesized a novel oat ß-glucan (OBG)-Cr(III) complex (OBG-Cr(III)) and explored its structure, inhibitory effects on α-amylase and α-glucosidase, and hypoglycemic activities and mechanism in vitro using an insulin-resistant HepG2 (IR-HepG2) cell model. The Cr(III) content in the complex was found to be 10.87%. The molecular weight of OBG-Cr(III) was determined to be 7.736 × 104 Da with chromium ions binding to the hydroxyl groups of OBG. This binding resulted in the increased asymmetry and altered spatial conformation of the complex along with significant changes in morphology and crystallinity. Our findings demonstrated that OBG-Cr(III) exhibited inhibitory effects on α-amylase and α-glucosidase. Furthermore, OBG-Cr(III) enhanced the insulin sensitivity of IR-HepG2 cells, promoting glucose uptake and metabolism more efficiently than OBG alone. The underlying mechanism of its hypoglycemic effect involved the modulation of the c-Cbl/PI3K/AKT/GLUT4 signaling pathway, as revealed by Western blot analysis. This research not only broadened the applications of OBG but also positioned OBG-Cr(III) as a promising Cr(III) supplement with enhanced hypoglycemic benefits.


Assuntos
Cromo , Hipoglicemiantes , alfa-Glucosidases , beta-Glucanas , Humanos , Cromo/química , Cromo/farmacologia , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/síntese química , beta-Glucanas/química , beta-Glucanas/farmacologia , Células Hep G2 , alfa-Glucosidases/metabolismo , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo , Resistência à Insulina , Glucose/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transportador de Glucose Tipo 4/metabolismo , Avena/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/química , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/síntese química
3.
Opt Lett ; 48(15): 3997-4000, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37527102

RESUMO

We propose a digital-delta-sigma-modulation radio-over-fiber (DDSM-RoF) scheme for wireless fronthaul and validate it experimentally in a D-band photonics-aided RoF transmission system. The 10-Gbaud DDSM-RoF signal with a common public radio interface equivalent data rate (CPRI-EDR) of 55.8 Gb/s is successfully transmitted in a 130-GHz 4.6-km wireless channel. The spectral efficiency (SE) is 5.58 bit/s/Hz and the capacity-distance product reaches 257 Gb/s·km. Up to 34.4-dB recovered signal-to-noise ratio (SNR) is observed to support the 1024-quadrature-amplitude-modulation (1024-QAM) transmission. Compared with the digital-analog-RoF (DA-RoF) scheme, the proposed DDSM-RoF achieves an SNR improvement of 5.9 dB.

4.
PLoS One ; 11(3): e0150363, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26963384

RESUMO

The neovascularization network of pannus formation plays a crucial role in the development of rheumatoid arthritis (RA). Annexin a2 (Axna2) is an important mediating agent that induces angiogenesis in vascular diseases. The correlation between Axna2 and pannus formation has not been studied. Here, we provided evidence that compared to osteoarthritis (OA) patients and healthy people, the expression of Axna2 and Axna2 receptor (Axna2R) were up-regulated in patients with RA. Joint swelling, inflammation and neovascularization were increased significantly in mice with collagen-induced arthritis (CIA) that were exogenously added Axna2. Cell experiments showed that Axna2 promoted HUVEC proliferation by binding Axna2R, and could activate Hedgehog (HH) signaling and up-regulate the expression of Ihh and Gli. Besides, expression of Ihh, Patched (Ptc), Smoothened (Smo) and Gli and matrix metalloproteinase-2 (MMP-2), vascular endothelial growth factor (VEGF) and angiopoietin-2 (Ang-2), angiogenic growth factor of HH signaling downstream, were down-regulated after inhibition of expression Axna2R on HUVEC. Together, our research definitely observed that over-expression of Axna2 could promote the development of CIA, especially during the process of pannus formation for the first time. Meanwhile, Axna2 depended on combining Axna2R to activate and enlarge HH signaling and the expression of its downstream VEGF, Ang-2 and MMP-2 to promote HUVEC proliferation, and eventually caused to angiogenesis. Therefore, the role of Axna2 is instructive for understanding the development of RA, suppress the effect of Axna2 might provide a new potential measure for treatment of RA.


Assuntos
Anexina A2/metabolismo , Artrite Experimental/metabolismo , Artrite Reumatoide/metabolismo , Proteínas Hedgehog/metabolismo , Neovascularização Patológica/metabolismo , Transdução de Sinais , Animais , Artrite Experimental/patologia , Artrite Reumatoide/patologia , Linhagem Celular Transformada , Proliferação de Células , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos DBA , Neovascularização Patológica/patologia , Receptores Acoplados a Proteínas G/metabolismo , Receptor Smoothened , Fator A de Crescimento do Endotélio Vascular/metabolismo
5.
Hepatology ; 56(5): 1631-40, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22610915

RESUMO

UNLABELLED: Hepatitis C virus (HCV) infection usually induces chronic hepatic inflammation, which favors the initiation and progression of hepatocellular carcinoma (HCC). Moreover, microRNA-155 (miR-155) plays an important role in regulating both inflammation and tumorigenesis. However, little is known about whether and how miR-155 provides the link between inflammation and cancer. In this study we found that miR-155 levels were markedly increased in patients infected with HCV. MiR-155 transcription was regulated by nuclear factor kappa B (NF-κB), and p300 increased NF-κB-dependent miR-155 expression. The overexpression of miR-155 significantly inhibited hepatocyte apoptosis and promoted cell proliferation, whereas miR-155 inhibition induced G(0) /G(1) arrest. Up-regulated miR-155 resulted in nuclear accumulation of ß-catenin and a concomitant increase in cyclin D1, c-myc, and survivin. Gain-of-function and loss-of-function studies demonstrated that miR-155 promoted hepatocyte proliferation and tumorigenesis by increasing Wnt signaling in vitro and in vivo, and DKK1 (Wnt pathway inhibitor) overexpression inhibited the biological role of miR-155 in hepatocytes. Finally, adenomatous polyposis coli (APC), which negatively regulates Wnt signaling, was identified as the direct and functional target of miR-155. CONCLUSION: HCV-induced miR-155 expression promotes hepatocyte proliferation and tumorigenesis by activating Wnt signaling. The present study provides a better understanding of the relationship between inflammation and tumorigenesis, and thus may be helpful in the development of effective diagnosis and treatment strategies against HCV-HCC.


Assuntos
Proteína da Polipose Adenomatosa do Colo/metabolismo , Carcinoma Hepatocelular/metabolismo , Hepatite C Crônica/metabolismo , Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , Via de Sinalização Wnt , Adulto , Idoso , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica , Quimiocina CXCL10/sangue , Ciclina D1/metabolismo , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular , Hepacivirus , Hepatite C Crônica/sangue , Hepatócitos , Humanos , Proteínas Inibidoras de Apoptose/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/sangue , MicroRNAs/genética , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Viral/metabolismo , Survivina , Transfecção , Regulação para Cima , beta Catenina/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo
6.
Mol Biol Rep ; 37(3): 1591-6, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19455404

RESUMO

Annexin B2 (AnxB2) is a novel member of the annexin family of Ca(2+)- and phospholipid-binding proteins from Cysticercus cellulosae. To obtain highly pure AnxB2 with an easy and inexpensive purification approach, its cDNA was cloned into the prokaryotic expression vector pJLA503 and the translation initiation codon was immediately under the control of the inducible bacteriophage lambda promoters P(R) and P(L). After induction by shifting temperature, large amounts of non-fusion protein were produced in Escherichia coli in a soluble form. Then a novel purification method based on Ca(2+)-dependent phosphatidylserine (PS)-binding activity was established, whereby the purity of AnxB2 was increased to 98.7%. Western blot analysis showed that recombinant AnxB2 was specifically recognized by serum of pigs infected with cysticercosis. In vitro test showed that, the recombinant AnxB2 had anticoagulant activity and platelet binding activity. The expression, purification, and initial characterization of AnxB2 set an important stage for further characterization of the protein.


Assuntos
Anexinas/genética , Proteínas de Ligação ao Cálcio/genética , Cysticercus/genética , Proteínas de Helminto/genética , Sequência de Aminoácidos , Animais , Anexinas/metabolismo , Bacteriófago lambda , Western Blotting , Proteínas de Ligação ao Cálcio/metabolismo , Cromatografia Líquida de Alta Pressão , Clonagem Molecular , Primers do DNA/genética , DNA Complementar/genética , Eletroforese em Gel de Poliacrilamida , Escherichia coli , Vetores Genéticos , Proteínas de Helminto/metabolismo , Dados de Sequência Molecular , Análise de Sequência de Proteína
7.
Hepatology ; 49(5): 1492-502, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19206147

RESUMO

UNLABELLED: To develop a hepatitis B virus (HBV) therapeutic vaccine that can induce a broad but specific immune response and significant antitumor effects both in vivo and in vitro, we inserted HBV X protein (HBx)-derived epitopes HBx(52-60), HBx(92-100), and HBx(115-123); a novel subdominant cytolytic T lymphocyte (CTL) epitope HBx(140-148); and the universal T helper epitope pan human leukocyte antigen DR-binding epitope into HBV core protein to form multiepitope peptide-loaded virus-like particles (VLPs). CTL responses against epitope-loaded VLPs were elicited by priming with VLP-pulsed dendritic cells in both HLA-A*0201 transgenic (Tg) mice and peripheral blood lymphocytes from HLA-A2(+)/HBx(+) HBV-infected hepatocellular carcinoma (HCC) patients. The multiepitope peptide-loaded VLPs demonstrated significantly higher immunogenicity in Tg mice than any single responsive epitope. Significant antitumor effects were demonstrated both with primary cultured autologous HCC cells in vitro and tumor-bearing Tg mice in vivo in an HLA-A2-restricted and epitope-specific fashion. CONCLUSION: The significant antitumor effects both in vivo and in vitro demonstrate the potential of multiepitope peptide-loaded VLPs as a vaccine against HCC.


Assuntos
Carcinoma Hepatocelular/imunologia , Epitopos de Linfócito T , Vacinas contra Hepatite B/biossíntese , Neoplasias Hepáticas/imunologia , Transativadores/imunologia , Proteínas Virais Reguladoras e Acessórias/imunologia , Transferência Adotiva , Animais , Carcinoma Hepatocelular/virologia , Linhagem Celular Tumoral , Citotoxicidade Imunológica , Células Dendríticas/imunologia , Antígenos HLA-A/metabolismo , Antígeno HLA-A2 , Humanos , Neoplasias Hepáticas/virologia , Camundongos , Camundongos Transgênicos , Estabilidade Proteica , Vacinação , Vacinas de Subunidades Antigênicas/biossíntese
8.
Biol Chem ; 388(6): 601-10, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17552907

RESUMO

We previously reported cloning of the Taenia solium annexin B1 gene from a metacestode cDNA expression library and demonstrated that it acts as a protective antigen for effective vaccine development against cysticercosis. In the present study we produced recombinant annexin B1 and antiserum against the protein to investigate its structural and functional properties. Western blotting of metacestode fractions indicated that T. solium annexin B1, similar to vertebrate annexins, associates with acid phospholipids in the presence of Ca(2+). This property was confirmed by the recognition of apoptotic cells by labeled annexin B1. CD spectroscopy results demonstrated that alpha-helices are the main secondary structures of the protein. Ca(2+) binding increases the alpha-helix content and causes significant thermal stabilization with a melting temperature increase of approximately 10 degrees C. Functional Ca(2+)-dependent phospholipid binding sites of annexin B1 were investigated using mutant proteins. By changing a conserved acidic amino acid residue that putatively combines Ca(2+) in each domain of annexin B1 singly or in combination, we found that Ca(2+) binding in the first domain is more important than that at the other Ca(2+) binding sites. Annexin B1 is a metacestode stage-specific antigen, with the protein being mainly localized in the teguments and surrounding cyst wall of T. solium metacestodes, suggesting a role in the parasite-host interaction.


Assuntos
Anexinas/metabolismo , Proteínas de Helminto/metabolismo , Animais , Anexinas/química , Anexinas/genética , Anexinas/farmacologia , Sítios de Ligação , Coagulação Sanguínea/efeitos dos fármacos , Cálcio/metabolismo , DNA Complementar/genética , DNA de Helmintos/genética , Expressão Gênica , Proteínas de Helminto/química , Proteínas de Helminto/genética , Proteínas de Helminto/farmacologia , Humanos , Modelos Moleculares , Mutagênese Sítio-Dirigida , Tempo de Tromboplastina Parcial , Fosfatidilcolinas/metabolismo , Fosfatidilserinas/metabolismo , Estrutura Secundária de Proteína , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Taenia solium
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