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2.
PLoS Pathog ; 10(1): e1003845, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24391501

RESUMEN

Innate cytokine response provides the first line of defense against influenza virus infection. However, excessive production of cytokines appears to be critical in the pathogenesis of influenza virus. Interferon lambdas (IFN-λ) have been shown to be overproduced during influenza virus infection, but the precise pathogenic processes of IFN-λ production have yet to be characterized. In this report, we observed that influenza virus induced robust expression of IFN-λ in alveolar epithelial cells (A549) mainly through a RIG-I-dependent pathway, but IFN-λ-induced phosphorylation of the signal transducer and activator of transcription protein 1 (STAT1) was dramatically inhibited in the infected cells. Remarkably, influenza virus infection induced robust expression of suppressor of cytokine signaling-1 (SOCS-1), leading to inhibition of STAT1 activation. Interestingly, the virus-induced SOCS-1 expression was cytokine-independent at early stage of infection both in vitro and in vivo. Using transgenic mouse model and distinct approaches altering the expression of SOCS-1 or activation of STAT signaling, we demonstrated that disruption of the SOCS-1 expression or expression of constitutively active STAT1 significantly reduced the production of IFN-λ during influenza virus infection. Furthermore, we revealed that disruption of IFN-λ signaling pathway by increased SOCS-1 protein resulted in the activation of NF-κB and thereby enhanced the IFN-λ expression. Together, these data imply that suppression of IFN-λ signaling by virus-induced SOCS-1 causes an adaptive increase in IFN-λ expression by host to protect cells against the viral infection, as a consequence, leading to excessive production of IFN-λ with impaired antiviral response.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A/inmunología , Interferones/inmunología , Infecciones por Orthomyxoviridae/inmunología , Transducción de Señal/inmunología , Proteínas Supresoras de la Señalización de Citocinas/inmunología , Animales , Células Epiteliales/inmunología , Células Epiteliales/patología , Células Epiteliales/virología , Femenino , Regulación de la Expresión Génica/inmunología , Subtipo H1N1 del Virus de la Influenza A/genética , Interferones/genética , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos , Infecciones por Orthomyxoviridae/genética , Infecciones por Orthomyxoviridae/patología , Alveolos Pulmonares/inmunología , Alveolos Pulmonares/patología , Alveolos Pulmonares/virología , Transducción de Señal/genética , Proteína 1 Supresora de la Señalización de Citocinas , Proteínas Supresoras de la Señalización de Citocinas/genética
3.
Orthop Surg ; 16(3): 766-774, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38296797

RESUMEN

For Crowe IV dysplasia, the clinical efficacy and surgical technique of subtrochanteric osteotomy (SO) within the direct anterior approach total hip arthroplasty (DAA-THA) was a subject of debate. This study aimed to describe the surgical technique and clinical outcomes in 11 cases of SO in DAA-THA and to summarize the relevant literature on this topic. Between June 2016 and June 2023, we retrospectively evaluated patients diagnosed with Crowe IV hip dysplasia at our institution. Criteria identified 11 patients who underwent SO during DAA-THA. Comprehensive data encompassing demographic information, radiological data, prosthetic implant type, and surgical intricacies were collected. In addition, an exhaustive review of existing case series literature was undertaken utilizing the PubMed databases. There were no revisions, deaths, dislocations, or infections. One hip (9.09%) had an intraoperative proximal split fracture, two hips (18.2%) had lower limb deep vein thrombosis, and one hip (9.09%) had symptoms of femoral nerve injury. Radiological data showed improved bilateral femoral offset, leg length discrepancy, and anatomical acetabular. During the mean follow-up of 2.18(1.06-2.46) years, patients demonstrated enhanced functional outcomes, with average changes of 25.2 in the Harris hip score and 47 in the WOMAC score. Reviewing the literature, most studies have favored S-ROM prostheses and transverse osteotomy techniques. Intraoperative fractures were notably frequent, with rates peaking at 25%. Nonunion and nerve injury were secondary common complications. SO via DAA-THA may offer satisfactory clinical and radiographic outcomes, but the literature review underscores the need for heightened awareness of intraoperative fracture risk. Proximal detachment of the vastus intermedius plays a pivotal role in SO exposure through the DAA.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Humanos , Artroplastia de Reemplazo de Cadera/métodos , Estudios Retrospectivos , Antivirales , Fémur/cirugía , Osteotomía/métodos , Complicaciones Intraoperatorias/cirugía
4.
Sheng Wu Gong Cheng Xue Bao ; 30(4): 615-24, 2014 Apr.
Artículo en Zh | MEDLINE | ID: mdl-25195251

RESUMEN

The antimicrobial peptide magainin II is expressed in the skin of the African clawed frog, Xenopus laevis, and exhibits a broad spectrum of antimicrobial activity as well as tumoricidal properties at low concentrations. In addition, magaininII plays a synergistic role during antimicrobial and tumoricidal processes with another antimicrobial peptide PGLa that is also expressed in Xenopus laevis. The optimized cDNA sequence of magainin II and magainin II-PGLa hybrid peptide according to E. coli or Pichia pastoris codon usage frequency were synthesized and sub-cloned into prokaryotic expression vector pGEX and Pichia pastoris secreted expression vector pPIC9k. The resulting recombinant plasmids were named as pGEX-magainin II and pPIC9k-magainin II-PGLa. The GST-magainin II fusion protein was highly expressed in E. coli. Furthermore, magainin II was successfully purified by digestion with PreScission Protease to cleave the GST tag. Additionally, our data obtained from the ELISA revealed that magainin II -PGLa hybrid peptide was successfully expressed in Pichia pastoris. These experiments establish a useful system for further studies of these antimicrobial peptides.


Asunto(s)
Magaininas/biosíntesis , Péptidos/metabolismo , Proteínas de Xenopus/biosíntesis , Animales , Escherichia coli/metabolismo , Vectores Genéticos , Magaininas/genética , Péptidos/genética , Pichia/metabolismo , Plásmidos , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/genética , Proteínas de Xenopus/genética , Xenopus laevis
5.
FEBS Lett ; 588(9): 1780-6, 2014 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-24685695

RESUMEN

Dysregulation of non-coding RNA H19 has been observed in various tumors. However, it remains unknown whether H19 is involved in Bcr-Abl-induced leukemia. Here, we demonstrate a critical requirement for H19 in Bcr-Abl-mediated tumorigenesis. H19 was highly expressed in Bcr-Abl-transformed cell lines and primary cells derived from patients in a Bcr-Abl kinase-dependent manner. Silencing H19 expression sensitized leukemic cells to undergo imatinib-induced apoptosis and inhibited Bcr-Abl-induced tumor growth. Furthermore, H19 was shown to be regulated by c-Myc in Bcr-Abl-expressing cells. These results reveal an important role H19 plays in Bcr-Abl-mediated transformation and provide novel insights into complex mechanisms underlying Bcr-Abl-induced cancers.


Asunto(s)
Transformación Celular Neoplásica/genética , Proteínas de Fusión bcr-abl/genética , ARN Largo no Codificante/genética , Animales , Supervivencia Celular , Transformación Celular Neoplásica/metabolismo , Femenino , Proteínas de Fusión bcr-abl/metabolismo , Expresión Génica , Regulación Leucémica de la Expresión Génica , Humanos , Células Jurkat , Células K562 , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Proteínas Proto-Oncogénicas c-myc/metabolismo , ARN Largo no Codificante/metabolismo
6.
PLoS One ; 9(10): e111611, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25360622

RESUMEN

CDKN3 (cyclin-dependent kinase inhibitor 3), a dual specificity protein phosphatase, dephosphorylates cyclin-dependent kinases (CDKs) and thus functions as a key negative regulator of cell cycle progression. Deregulation or mutations of CDNK3 have been implicated in various cancers. However, the role of CDKN3 in Bcr-Abl-mediated chronic myelogenous leukemia (CML) remains unknown. Here we found that CDKN3 acts as a tumor suppressor in Bcr-Abl-mediated leukemogenesis. Overexpression of CDKN3 sensitized the K562 leukemic cells to imanitib-induced apoptosis and dramatically inhibited K562 xenografted tumor growth in nude mouse model. Ectopic expression of CDKN3 significantly reduced the efficiency of Bcr-Abl-mediated transformation of FDCP1 cells to growth factor independence. In contrast, depletion of CDKN3 expression conferred resistance to imatinib-induced apoptosis in the leukemic cells and accelerated the growth of xenograph leukemia in mice. In addition, we found that CDKN3 mutant (CDKN3-C140S) devoid of the phosphatase activity failed to affect the K562 leukemic cell survival and xenografted tumor growth, suggesting that the phosphatase of CDKN3 was required for its tumor suppressor function. Furthermore, we observed that overexpression of CDKN3 reduced the leukemic cell survival by dephosphorylating CDK2, thereby inhibiting CDK2-dependent XIAP expression. Moreover, overexpression of CDKN3 delayed G1/S transition in K562 leukemic cells. Our results highlight the importance of CDKN3 in Bcr-Abl-mediated leukemogenesis, and provide new insights into diagnostics and therapeutics of the leukemia.


Asunto(s)
Carcinogénesis/metabolismo , Carcinogénesis/patología , Proteínas Inhibidoras de las Quinasas Dependientes de la Ciclina/metabolismo , Fosfatasas de Especificidad Dual/metabolismo , Proteínas de Fusión bcr-abl/metabolismo , Animales , Carcinogénesis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Transformación Celular Neoplásica/efectos de los fármacos , Transformación Celular Neoplásica/patología , Quinasa 2 Dependiente de la Ciclina/metabolismo , Femenino , Fase G1/efectos de los fármacos , Humanos , Mesilato de Imatinib/farmacología , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Células K562 , Ratones Desnudos , Fosforilación/efectos de los fármacos , Fase S/efectos de los fármacos , Proteína Inhibidora de la Apoptosis Ligada a X/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Cell Host Microbe ; 16(5): 616-26, 2014 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-25525793

RESUMEN

Long noncoding RNAs (lncRNAs) modulate various biological processes, but their role in host antiviral responses is largely unknown. Here we identify a lncRNA as a key regulator of antiviral innate immunity. Following from the observation that a lncRNA that we call negative regulator of antiviral response (NRAV) was dramatically downregulated during infection with several viruses, we ectopically expressed NRAV in human cells or transgenic mice and found that it significantly promotes influenza A virus (IAV) replication and virulence. Conversely, silencing NRAV suppressed IAV replication and virus production, suggesting that reduction of NRAV is part of the host antiviral innate immune response to virus infection. NRAV negatively regulates the initial transcription of multiple critical interferon-stimulated genes (ISGs), including IFITM3 and MxA, by affecting histone modification of these genes. Our results provide evidence for a lncRNA in modulating the antiviral interferon response.


Asunto(s)
Inmunidad Innata , Virus de la Influenza A/patogenicidad , Interferones/inmunología , Infecciones por Orthomyxoviridae/inmunología , ARN Largo no Codificante/genética , Transcripción Genética , Animales , Línea Celular Tumoral , Regulación hacia Abajo , Silenciador del Gen , Interacciones Huésped-Patógeno , Humanos , Virus de la Influenza A/fisiología , Proteínas de la Membrana/metabolismo , Ratones , Ratones Transgénicos , Análisis por Micromatrices , Datos de Secuencia Molecular , Proteínas de Resistencia a Mixovirus/metabolismo , Regiones Promotoras Genéticas , Replicación Viral
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