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1.
Viruses ; 13(10)2021 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-34696464

RESUMEN

Autophagic machinery is involved in selective and non-selective recruitment as well as degradation or exocytosis of cargoes, including pathogens. Dengue virus (DENV) infectioninduces autophagy that enhances virus replication and vesicle release to evade immune systemsurveillance. This study reveals that DENV2 induces autophagy in lung and liver cancer cells andshowed that DENV2 capsid, envelope, NS1, NS3, NS4B and host cell proinflammatory high mobilitygroup box 1 (HMGB1) proteins associated with autophagosomes which were purified by gradientcentrifugation. Capsid, NS1 and NS3 proteins showing high colocalization with LC3 protein in thecytoplasm of the infected cells were detected in the purified double-membrane autophagosome byimmunogold labeling under transmission electron microscopy. In DENV infected cells, the levels ofcapsid, envelope, NS1 and HMGB1 proteins are not significantly changed compared to the dramaticaccumulation of LC3-II and p62/SQSTM1 proteins when autophagic degradation was blocked bychloroquine, indicating that these proteins are not regulated by autophagic degradation machinery.We further demonstrated that purified autophagosomes were infectious when co-cultured withuninfected cells. Notably, these infectious autophagosomes contain DENV2 proteins, negativestrandand full-length genomic RNAs, but no viral particles. It is possible that the infectivity ofthe autophagosome originates from the full-length DENV RNA. Moreover, we reveal that DENV2promotes HMGB1 exocytosis partially through secretory autophagy. In conclusion, we are the firstto report that DENV2-induced double-membrane autophagosomes containing viral proteins andfull-length RNAs are infectious and not undergoing autophagic degradation. Our novel findingwarrants further validation of whether these intracellular vesicles undergo exocytosis to becomeinfectious autophagic vesicles.


Asunto(s)
Autofagosomas/genética , Autofagosomas/metabolismo , Virus del Dengue/genética , Células A549 , Animales , Autofagosomas/virología , Autofagia/genética , Línea Celular Tumoral , Chlorocebus aethiops , Dengue/virología , Genómica , Proteína HMGB1 , Humanos , Neoplasias Hepáticas , ARN/metabolismo , Células Vero , Virión , Replicación Viral
2.
Comput Math Methods Med ; 2020: 8723571, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32411287

RESUMEN

V-Y flap is widely used in plastic surgery as an important technique for reconstructing deformities and improving appearance. In this paper, a geometrical parameter model and finite element analysis were used to study the rationale of the proposed V-Y flap design and the preoperative evaluation of the V-Y flap design. First, a geometric parameter model of the V-Y flap was established to analyze the five key geometric relationships affecting the flap structure and obtain a reasonable plan for the V-Y flap design through the crossing constraint relationship. Second, in order to verify the effectiveness of the V-Y flap design, the suture and release states of the V-Y flap during surgery were evaluated based on a simulation model of the V-Y flap generated by finite element analysis software. The results revealed that the approach proposed in this paper provides a feasible method for clinical V-Y flap design.


Asunto(s)
Modelos Anatómicos , Procedimientos de Cirugía Plástica/métodos , Colgajos Quirúrgicos , Biología Computacional , Simulación por Computador , Diseño Asistido por Computadora , Análisis de Elementos Finitos , Humanos , Cuidados Preoperatorios , Procedimientos de Cirugía Plástica/estadística & datos numéricos , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/cirugía , Estrés Mecánico , Cirugía Asistida por Computador , Colgajos Quirúrgicos/patología , Colgajos Quirúrgicos/fisiología , Colgajos Quirúrgicos/cirugía
3.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1012-1013: 79-88, 2016 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-26812177

RESUMEN

Neurotransmitters (NTs) and their metabolites are known to play an essential role in maintaining various physiological functions in nervous system. However, there are many difficulties in the detection of NTs together with their metabolites in biological samples. A new method for NTs and their metabolites detection by high performance liquid chromatography coupled with Q Exactive hybrid quadruple-orbitrap high-resolution accurate mass spectrometry (HPLC-HRMS) was established in this paper. This method was a great development of the applying of Q Exactive MS in the quantitative analysis. This method enabled a rapid quantification of ten compounds within 18min. Good linearity was obtained with a correlation coefficient above 0.99. The concentration range of the limit of detection (LOD) and the limit of quantitation (LOQ) level were 0.0008-0.05nmol/mL and 0.002-25.0nmol/mL respectively. Precisions (relative standard deviation, RSD) of this method were at 0.36-12.70%. Recovery ranges were between 81.83% and 118.04%. Concentrations of these compounds in mouse hypothalamus were detected by Q Exactive LC-MS technology with this method.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Hipotálamo/química , Neurotransmisores/análisis , Animales , Límite de Detección , Modelos Lineales , Masculino , Ratones , Neurotransmisores/metabolismo , Reproducibilidad de los Resultados
4.
Bioorg Med Chem Lett ; 25(2): 285-7, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25488843

RESUMEN

A series of novel arylpiperazine derivatives was synthesized. The in vitro cytotoxic activities of all synthesized compounds against three human prostate cancer cell lines (PC-3, LNCaP, and DU145) were evaluated by a CCK-8 assay. Compounds 10, 24 and 29 exhibited strong cytotoxic activities against LNCaP cells (IC50 <3µM). In addition, these compounds exhibited weak cytotoxic effects on human epithelial prostate normal cells RWPE-1. The structure-activity relationship (SAR) of these arylpiperazine derivatives was also discussed based on the obtained experimental data.


Asunto(s)
Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Diseño de Fármacos , Piperazinas/síntesis química , Piperazinas/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Masculino , Modelos Moleculares , Estructura Molecular , Neoplasias de la Próstata/patología , Relación Estructura-Actividad , Células Tumorales Cultivadas
5.
J Chromatogr Sci ; 53(2): 285-94, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24920653

RESUMEN

A simple method based on liquid chromatography-full-scan high-resolution accurate mass spectrometry (LC-HRMS) using a quadrupole time-of-flight (TOF) mass spectrometry was developed and optimized for corticosterone quantification in mouse plasma. Mouse plasma (100 µL) was extracted with methyl tert-butyl ether using prednisone as internal standard. Separation was performed on a short C18 column using a methanol-water gradient. Full-scan data were acquired in the TOF only mode, and extracted ion chromatograms were generated post-acquisition with the extract masses of the analytes. Enhanced sensitivity and reproducibility were acquired with optimized mass parameters. The calibration range was 8.24-412 ng/mL, and the limit of quantitation was 5.088 g/mL. Accuracy was between -5.9 and 8.6%. The precision of between-run (interday) and within-run (intraday) was within 5.6 and 6.9%, respectively. The LC-HRMS method was applied for plasma samples analysis from the stressed mice with and without ginseng treatment for the stress state estimation.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Corticosterona/sangre , Espectrometría de Masa por Ionización de Electrospray/métodos , Animales , Modelos Lineales , Masculino , Ratones , Panax , Reproducibilidad de los Resultados , Saponinas , Sensibilidad y Especificidad
6.
Int J Mol Med ; 27(1): 63-9, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21069266

RESUMEN

Wnt5a has been shown to be involved in cancer progression in a variety of tumor types, and regulates multiple intracellular signaling cascades; it is a representative ligand that activates a noncanonical Wnt signaling pathway. The mechanism governing how Wnt5a determines the specificity of these pathways and the relationship with tumorigenesis is still unknown. In this study, we aimed to clarify the tumor suppressor role of Wnt5a in leukemogenesis. In particular, we focused on Ror2 functioning as a Wnt5a receptor to mediate noncanonical Wnt signaling, which inhibits canonical Wnt signaling in K562 cells. We found that up-regulation of Wnt5a expression increased Ror2 expression in K562 cells and Wnt5a and Ror2 were co-expressed in the cytoplasm. Also, Wnt5a induced the intrnalization of Ror2. Co-immunoprecipitation experiments were performed to determine whether Ror2 binds to Wnt5a, and inhibits Wnt5a binding with Frizzled4 and LRP5 in Wnt5a treated K562 cells. Wnt5a had no effect on total ß-catenin expression levels, but regulated tyrosine phosphorylation of ß-catenin and translocation of ß-catenin from the cytoplasm to the nucleus. Furthermore, expression of Wnt5a was associated with suppression of ß-catenin/TCF-dependent transcriptional activity and down-regulated the expression of cyclin D1, a downstream target gene of the canonical Wnt signaling pathway. We hypothesize that Wnt5a plays the role of a tumor suppressor in leukemogenesis through the Wnt5a/Ror2 noncanonical signaling pathway that inhibits Wnt canonical signaling.


Asunto(s)
Células K562/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Receptores Huérfanos Similares al Receptor Tirosina Quinasa/metabolismo , Transducción de Señal/fisiología , Proteínas Wnt/metabolismo , Ciclina D1/genética , Ciclina D1/metabolismo , Humanos , Células K562/ultraestructura , Proteínas Relacionadas con Receptor de LDL/genética , Proteínas Relacionadas con Receptor de LDL/metabolismo , Proteína-5 Relacionada con Receptor de Lipoproteína de Baja Densidad , Fosforilación , Proteínas Proto-Oncogénicas/genética , Receptores Huérfanos Similares al Receptor Tirosina Quinasa/genética , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Proteínas Wnt/genética , Proteína Wnt-5a , beta Catenina/metabolismo
7.
Biochemistry ; 46(48): 13762-74, 2007 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-17985930

RESUMEN

The crystal structure of the particulate methane monooxygenase (pMMO) from Methylococcus capsulatus (Bath) has been reported recently [Lieberman, R. L., and Rosenzweig, A. C. (2005) Crystal structure of a membrane-bound metalloenzyme that catalyses the biological oxidation of methane, Nature 434, 177-182]. Subsequent work has shown that the preparation on which the X-ray analysis is based might be missing many of the important metal cofactors, including the putative trinuclear copper cluster at the active site as well as ca. 10 copper ions (E-clusters) that have been proposed to serve as a buffer of reducing equivalents to re-reduce the copper atoms at the active site following the catalytic chemistry [Chan, S. I., Wang, V. C.-C., Lai, J. C.-H., Yu, S. S.-F., Chen, P. P.-Y., Chen, K. H.-C., Chen, C.-L., and Chan, M. K. (2007) Redox potentiometry studies of particulate methane monooxygenase: Support for a trinuclear copper cluster active site, Angew. Chem., Int. Ed. 46, 1992-1994]. Since the aqueous-exposed domains of the 45 kDa subunit (PmoB) have been suggested to be the putative binding domains for the E-cluster copper ions, we have cloned and overexpressed in Escherichia coli the two aqueous-exposed subdomains toward the N- and C-termini of the subunit: the N-terminal subdomain (residues 54-178) and the C-terminal subdomain (residues 257-394 and 282-414). The recombinant C-terminal water-exposed subdomain is shown to behave like a Cu(I) sponge, taking up to ca. 10 Cu(I) ions cooperatively when cupric ions are added to the protein fragment in the presence of dithiothreitol or ascorbate. In addition, circular dichroism measurements reveal that the C-terminal subdomain folds into a beta-sheet structure in the presence of Cu(I). The propensity for the C-terminal subdomain to bind Cu(I) is consistent with the high redox potential(s) determined for the E-cluster copper ions in the pMMO. These properties of the E-clusters are in accordance with the function proposed for these copper ions in the turnover cycle of the enzyme.


Asunto(s)
Cobre/química , Methylococcus capsulatus/enzimología , Oxigenasas/química , Secuencia de Aminoácidos , Secuencia de Bases , Dicroismo Circular , Cristalografía por Rayos X , Cartilla de ADN , Electroforesis en Gel de Poliacrilamida , Modelos Moleculares , Datos de Secuencia Molecular , Conformación Proteica , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Agua
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