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1.
Appl Opt ; 60(34): 10555-10563, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-35200917

RESUMO

3D measurement methods based on fringe projection have attracted extensive research. However, it is a challenge to deal with overshooting on a high-reflection or specular surface. To eliminate the saturated pixels caused by overshooting, we propose a projection intensity adaptive adjustment method. First, we project three uniform gray-level images and estimate the projection intensity of the measured surface through the captured uniform gray-level images. Then we can obtain the optimal projection fringes in the camera coordinate system. Second, a set of horizontal and vertical gray-coded patterns are used to establish a coordinate matching relationship between the projected image and the captured image. To check the decoding result of the gray-coded patterns, a set of horizontal and vertical sinusoidal fringes are used to calculate the high-reflection mapping area (HRMA) in the projector coordinate system. Through the distribution of HRMA, we can check whether the decoding is reliable or not. Finally, we project the optimal intensity fringes and obtain the measurement results. We develop a measurement system to verify the validity of the proposed method. Experimental results show that the proposed method can effectively avoid overshooting and obtain measurement results with a minimum rms error.

2.
Clin Infect Dis ; 66(5): 676-685, 2018 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-29040419

RESUMO

Background: mcr-1-mediated colistin resistance in Enterobacteriaceae is concerning, as colistin is used in treating multidrug-resistant Enterobacteriaceae infections. We identified trends in human fecal mcr-1-positivity rates and colonization with mcr-1-positive, third-generation cephalosporin-resistant (3GC-R) Enterobacteriaceae in Guangzhou, China, and investigated the genetic contexts of mcr-1 in mcr-1-positive 3GC-R strains. Methods: Fecal samples were collected from in-/out-patients submitting specimens to 3 hospitals (2011-2016). mcr-1 carriage trends were assessed using iterative sequential regression. A subset of mcr-1-positive isolates was sequenced (whole-genome sequencing [WGS], Illumina), and genetic contexts (flanking regions, plasmids) of mcr-1 were characterized. Results: Of 8022 fecal samples collected, 497 (6.2%) were mcr-1 positive, and 182 (2.3%) harbored mcr-1-positive 3GC-R Enterobacteriaceae. We observed marked increases in mcr-1 (0% [April 2011] to 31% [March 2016]) and more recent (since January 2014; 0% [April 2011] to 15% [March 2016]) increases in human colonization with mcr-1-positive 3GC-R Enterobacteriaceae (P < .001). mcr-1-positive 3GC-R isolates were commonly multidrug resistant. WGS of mcr-1-positive 3GC-R isolates (70 Escherichia coli, 3 Klebsiella pneumoniae) demonstrated bacterial strain diversity; mcr-1 in association with common plasmid backbones (IncI, IncHI2/HI2A, IncX4) and sometimes in multiple plasmids; frequent mcr-1 chromosomal integration; and high mobility of the mcr-1-associated insertion sequence ISApl1. Sequence data were consistent with plasmid spread among animal/human reservoirs. Conclusions: The high prevalence of mcr-1 in multidrug-resistant E. coli colonizing humans is a clinical threat; diverse genetic mechanisms (strains/plasmids/insertion sequences) have contributed to the dissemination of mcr-1, and will facilitate its persistence.


Assuntos
Portador Sadio/microbiologia , Colistina/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Portador Sadio/epidemiologia , Cefalosporinas/farmacologia , China/epidemiologia , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/microbiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Fezes/microbiologia , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Prevalência , Sequenciamento Completo do Genoma
3.
Antimicrob Agents Chemother ; 60(10): 6121-6, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27480855

RESUMO

CTX-M-140, a novel CTX-M-type extended-spectrum ß-lactamase (ESBL), was identified in cephalosporin-resistant clinical isolates of Proteus mirabilis CTX-M-140 contained an alanine-to-threonine substitution at position 109 compared to its putative progenitor, CTX-M-14. When it was expressed in an Escherichia coli isogenic background, CTX-M-140 conferred 4- to 32-fold lower MICs of cephalosporins than those with CTX-M-14, indicating that the phenotype was attributable to this single substitution. For four mutants of CTX-M-14 that were constructed by site-directed mutagenesis (A109E, A109D, A109K, and A109R mutants), MICs of cephalosporins were similar to those for the E. coli host strain, which suggested that the alanine at position 109 was essential for cephalosporin hydrolysis. The kinetic properties of native CTX-M-14 and CTX-M-140 were consistent with the MICs for the E. coli clones. Compared with that of CTX-M-14, a lower hydrolytic activity against cephalosporins was observed for CTX-M-140. blaCTX-M-140 is located on the chromosome as determined by I-CeuI pulsed-field gel electrophoresis (I-CeuI-PFGE) and Southern hybridization. The genetic environment surrounding blaCTX-M-140 is identical to the sequence found in different plasmids with blaCTX-M-9-group genes among the Enterobacteriaceae Genome sequencing and analysis showed that P. mirabilis strains with blaCTX-M-140 have a genome size of ∼4 Mbp, with a GC content of 38.7% and 23 putative antibiotic resistance genes. Our results indicate that alanine at position 109 is critical for the hydrolytic activity of CTX-M-14 against oxyimino-cephalosporins.


Assuntos
Substituição de Aminoácidos , Antibacterianos/metabolismo , Cefalosporinas/metabolismo , Genoma Bacteriano , Proteus mirabilis/enzimologia , beta-Lactamases/genética , Alanina/metabolismo , Antibacterianos/farmacologia , Composição de Bases , Cefalosporinas/farmacologia , Clonagem Molecular , Farmacorresistência Bacteriana/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Tamanho do Genoma , Hidrólise , Isoenzimas/genética , Isoenzimas/metabolismo , Testes de Sensibilidade Microbiana , Mutação , Proteus mirabilis/efeitos dos fármacos , Proteus mirabilis/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Treonina/metabolismo , beta-Lactamases/metabolismo
4.
J Cell Sci ; 127(Pt 11): 2471-82, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24659800

RESUMO

The formation of cytoplasmic stress granules and the innate immune response are two distinct cellular stress responses. Our study investigated the involvement of four innate immune proteins - retinoic-acid-inducible gene I (RIG-I, also known as DDX58), melanoma differentiation-associated gene 5 (MDA5, also known as IFIH1), IFN-ß promoter stimulator (IPS-1, also known as MAVS) and protein kinase regulated by dsRNA (PKR, also known as EIF2AK2) in the formation of stress granules. Knockdown of IPS-1 or PKR significantly decreased the formation of stress granules induced by double-stranded (ds)RNA. IPS-1 depletion markedly attenuated the phosphorylation of PKR and eIF2α that was triggered by dsRNA, and IPS-1 facilitated the in vitro autophosphorylation of PKR. In IPS-1-depleted cells, the dsRNA-mediated dimerization of PKR through its dsRNA-binding domains was significantly abrogated, suggesting that IPS-1 might be involved in PKR dimerization. By co-immunoprecipitation and pulldown assays, our data demonstrate that IPS-1 directly binds to PKR through the IPS-1 caspase activation and recruitment domain (CARD), suggesting that the effect of IPS-1 on the formation of stress granules might be exerted through interacting with PKR and mediating its activation. PKR was recruited into stress granules upon activation, whereas the majority of IPS-1 protein formed clusters on mitochondrial membranes. Our work provides the first evidence that the innate signaling molecule IPS-1 plays an essential role in stress granule formation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Grânulos Citoplasmáticos/metabolismo , Membranas Mitocondriais/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteína DEAD-box 58 , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Dimerização , Células HeLa , Temperatura Alta/efeitos adversos , Humanos , Imunidade Inata , Helicase IFIH1 Induzida por Interferon , Fosforilação/genética , Ligação Proteica , Transporte Proteico , RNA de Cadeia Dupla/metabolismo , RNA Interferente Pequeno/genética , Receptores Imunológicos , Esteróis/toxicidade , Estresse Fisiológico/genética , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo
5.
Antimicrob Agents Chemother ; 59(8): 5073-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26055374

RESUMO

We identified New Delhi metallo-ß-lactamase (NDM-1)-producing Citrobacter freundii GB032, Escherichia coli GB102, and Acinetobacter baumannii GB661 in urine and stool samples from a single patient in China. Plasmid profiling and Southern blotting indicated that blaNDM-1 from GB032 and that from GB102 were likely located on the same plasmid, while blaNDM-1 from GB661 was located on a very large (>400-kb) plasmid. This case underscores the broad host range of blaNDM-1 and its potential to spread between members of the family Enterobacteriaceae and A. baumannii.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Citrobacter freundii/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli/efeitos dos fármacos , beta-Lactamases/genética , Infecções por Acinetobacter/tratamento farmacológico , Acinetobacter baumannii/genética , Acinetobacter baumannii/isolamento & purificação , Antibacterianos/uso terapêutico , China , Citrobacter freundii/genética , Citrobacter freundii/isolamento & purificação , Infecções por Enterobacteriaceae/tratamento farmacológico , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Dados de Sequência Molecular , Tipagem de Sequências Multilocus , Plasmídeos/genética , Plasmídeos/isolamento & purificação , Urina/microbiologia , beta-Lactamases/biossíntese
6.
Biochem Biophys Res Commun ; 461(1): 148-53, 2015 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-25866185

RESUMO

Dengue virus (DENV) is a mosquito-borne flavivirus that causes the most prevalent diseases in tropical and subtropical regions. DENV utilizes host factors to facilitate its replication, while host cells intend to restrain virus replication. NS4A of DENV has been implicated to play a crucial role during viral replication. To identify more cellular proteins that are recruited by NS4A, we carried out a tandem affinity purification assay. The mass spectrometry data revealed that human eukaryotic initiation factor 4AI (eIF4AI) was one of potential NS4A-interacting partners. Co-immunoprecipitation data confirmed the interaction between NS4A and eIF4AI, and both the N-terminal ATP-binding domain and C-terminal helicase domain of eIF4AI were involved in their association. Functionally, silencing of eIF4AI by RNAi significantly increased the replication level of DENV1, DENV2 and DENV3. And knockdown of eIF4AI markedly attenuated the phosphorylation of protein kinase regulated by dsRNA-activated (PKR) and eIF2ɑ induced by DENV2 infection. Collectively, these data suggested that a potential role of NS4A in antagonizing host antiviral defense is by recruiting eIF4AI and escaping the translation inhibition mediated by PKR.


Assuntos
Vírus da Dengue/fisiologia , Fator de Iniciação 4A em Eucariotos/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/virologia , Proteínas não Estruturais Virais/metabolismo , Ativação Viral/fisiologia , Replicação Viral/fisiologia , Linhagem Celular Tumoral , Clonagem Molecular , Humanos
7.
PLoS Pathog ; 9(10): e1003697, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24130493

RESUMO

Mycobacterium tuberculosis is a hard-to-eradicate intracellular pathogen that infects one-third of the global population. It can live within macrophages owning to its ability to arrest phagolysosome biogenesis. Autophagy has recently been identified as an effective way to control the intracellular mycobacteria by enhancing phagosome maturation. In the present study, we demonstrate a novel role of miR-155 in regulating the autophagy-mediated anti-mycobacterial response. Both in vivo and in vitro studies showed that miR-155 expression was significantly enhanced after mycobacterial infection. Forced expression of miR-155 accelerated the autophagic response in macrophages, thus promoting the maturation of mycobacterial phagosomes and decreasing the survival rate of intracellular mycobacteria, while transfection with miR-155 inhibitor increased mycobacterial survival. However, macrophage-mediated mycobacterial phagocytosis was not affected after miR-155 overexpression or inhibition. Furthermore, blocking autophagy with specific inhibitor 3-methyladenine or silencing of autophagy related gene 7 (Atg7) reduced the ability of miR-155 to promote autophagy and mycobacterial elimination. More importantly, our study demonstrated that miR-155 bound to the 3'-untranslated region of Ras homologue enriched in brain (Rheb), a negative regulator of autophagy, accelerated the process of autophagy and sequential killing of intracellular mycobacteria by suppressing Rheb expression. Our results reveal a novel role of miR-155 in regulating autophagy-mediated mycobacterial elimination by targeting Rheb, and provide potential targets for clinical treatment.


Assuntos
Autofagia , Regulação da Expressão Gênica , Macrófagos/metabolismo , MicroRNAs/metabolismo , Proteínas Monoméricas de Ligação ao GTP/biossíntese , Mycobacterium tuberculosis/metabolismo , Neuropeptídeos/biossíntese , Animais , Proteína 7 Relacionada à Autofagia , Linhagem Celular , Macrófagos/microbiologia , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/genética , Viabilidade Microbiana , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Monoméricas de Ligação ao GTP/genética , Mycobacterium tuberculosis/genética , Neuropeptídeos/genética , Proteína Enriquecida em Homólogo de Ras do Encéfalo , Tuberculose/genética , Tuberculose/metabolismo , Tuberculose/patologia
8.
Arch Virol ; 158(4): 829-38, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23224759

RESUMO

Our study presents a first investigation of the effect of the adjuvant PIKA on dengue virus (DENV) replication. PIKA pretreatment decreased the levels of DENV serotype 2 (DENV2) mRNA, protein and viral particles in the hepatoma cell line HepG2. Treatment with PIKA simultaneously with DENV2 infection, but not after infection, resulted in a protective effect. Significant induction of type I and type III interferons (IFNs), as well as interferon-stimulated genes was detected in PIKA-pretreated cells. Neutralization of IFN-ß partially restored the replication levels of DENV2 in PIKA-pretreated cells, suggesting that IFN-ß is one of the mediators involved in the antiviral action of PIKA. Additionally, blockade of TBK-1 signaling largely restored the IFN induction and viral suppression effects mediated by PIKA, further illustrating that PIKA plays its anti-DENV role by promoting innate immunity. These findings suggest that PIKA is an attractive agent to be used in the prevention of DENV diseases.


Assuntos
Adjuvantes Imunológicos , Vírus da Dengue/imunologia , Proteínas Serina-Treonina Quinases/metabolismo , Replicação Viral/imunologia , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/farmacologia , Animais , Carcinoma Hepatocelular , Linhagem Celular , Culicidae/citologia , Vírus da Dengue/classificação , Vírus da Dengue/fisiologia , Relação Dose-Resposta Imunológica , Regulação da Expressão Gênica/imunologia , Humanos , Imunidade Inata , Interferons/imunologia , Interferons/metabolismo , Neoplasias Hepáticas , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais
9.
Infect Immun ; 79(7): 2709-16, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21555403

RESUMO

As a novel family of cell surface receptors, triggering receptors expressed on myeloid cells (TREMs) play an important role in inflammatory responses. However, the role of TREMs in the ocular immune system remains unknown. In this study, we examined the expression and function of TREM-1 in Pseudomonas aeruginosa keratitis, one of the most common sight-threatening ocular diseases. TREM-1 was significantly increased in human corneas after P. aeruginosa infection. Consistent with TREM-1 expression at the human ocular surface, TREM-1 levels (mRNA and protein) were also elevated in the infected corneas of C57BL/6 (B6) mice at 1, 3, and 5 days postinfection. To determine whether TREM-1 dictates the outcome of P. aeruginosa keratitis in susceptible mice, TREM-1 signaling in B6 mice was blocked with a soluble mTREM-1/Fc fusion protein. The results indicated that blockade of TREM-1 reduced the severity of corneal disease, polymorphonuclear neutrophil infiltration, Th1/proinflammatory cytokine expression and Toll-like receptor (TLR) activation but enhanced the production of Th2 cytokines, murine ß-defensin 2 (mBD2), single Ig interleukin-1R-related molecule (SIGIRR), and ST2. Furthermore, we also used agonistic anti-mTREM-1 antibody to activate TREM-1 signaling in B6 mice and found that TREM-1 activation resulted in worsened disease and earlier corneal perforation in infected B6 mouse corneas and elevated production of proinflammatory cytokines and TLR signaling molecules but reduced expression of mBD2, SIGIRR, and ST2. To the best of our knowledge, this study provides the first evidence that TREM-1 functions as an inflammatory amplifier in P. aeruginosa keratitis by modulating TLR signaling and Th1/Th2 responses.


Assuntos
Córnea/imunologia , Infecções Oculares Bacterianas/imunologia , Glicoproteínas de Membrana/metabolismo , Infecções por Pseudomonas/imunologia , Receptores Imunológicos/metabolismo , Receptores Toll-Like/metabolismo , Adulto , Idoso , Animais , Anticorpos , Córnea/metabolismo , Citocinas/biossíntese , Citocinas/metabolismo , Infecções Oculares Bacterianas/genética , Infecções Oculares Bacterianas/metabolismo , Feminino , Humanos , Proteína 1 Semelhante a Receptor de Interleucina-1 , Ceratite/imunologia , Ceratite/metabolismo , Ceratite/microbiologia , Masculino , Glicoproteínas de Membrana/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Infiltração de Neutrófilos , Neutrófilos/imunologia , Infecções por Pseudomonas/genética , Infecções por Pseudomonas/metabolismo , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/imunologia , Pseudomonas aeruginosa/metabolismo , Receptores Imunológicos/imunologia , Receptores de Interleucina/biossíntese , Receptores de Interleucina-1/biossíntese , Proteínas Recombinantes de Fusão/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Células Th1/imunologia , Células Th2/imunologia , Receptores Toll-Like/imunologia , Receptor Gatilho 1 Expresso em Células Mieloides , beta-Defensinas/biossíntese
10.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 25(3): 621-5, 2008 Jun.
Artigo em Zh | MEDLINE | ID: mdl-18693444

RESUMO

This study was designed to investigate the changes of prostaglandin I2 (PGI2) and nitric oxide (NO) secreted by endothelialized polyurethane small diameter artificial blood vessel. The peripheral blood mononuclear cells of healthy adult were separated and induced into endothelial progenitor cells (EPCs), which were identified by the methods of discrepancy microphage and fluorescent immunology labeling. After the induced cells being seeded on the polyurethane small-diameter artificial vessels, the endothelialized polyurethane small diameter artificial blood vessels were divided into four different experimental groups, including stationary group, low-flow shear stress group (5 dynes/cm2), medium-flow shearstress group (15 dynes/cm2), and high-flow shear stress group (25 dynes/cm2). Then, the levels of 6-ketoprostaglandin F1alpha (6-keto-PGF1alpha) and NO of different time were measured by enzyme-linked immunosorbent assay and nitrate reductase methods. The peripheral blood mononuclear cells differentiated into EPCs. They presented typical "spindie-shaped" appearance, and they were positively labeled by fluorescent acetylated-LDL, lectin, FLK-1 and vWF. Shear stress enhanced the production of NO and 6-keto-PGF1alpha by EPCs in a dose-dependent manner. Therefore, shear stress increases the secretion of NO and PGI2 by EPC, which suggests that shear stress can improve the antithrombogenic potentials of endothelialized polyurethane small diameter artificial blood vessel.


Assuntos
Órgãos Bioartificiais , Prótese Vascular , Células Endoteliais/citologia , Fibrinolíticos/metabolismo , Poliuretanos/química , Materiais Biocompatíveis/química , Adesão Celular , Diferenciação Celular , Células Cultivadas , Células Endoteliais/metabolismo , Epoprostenol/metabolismo , Humanos , Técnicas In Vitro , Leucócitos Mononucleares/citologia , Óxido Nítrico/metabolismo , Estresse Mecânico
11.
Front Immunol ; 9: 211, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29487594

RESUMO

Beta-defensins 2 and 3 (BD2 and BD3) are inducible peptides present at the sites of infection, and they are well characterized for their antimicrobial activities and immune-regulatory functions. However, no study has thoroughly investigated their immunomodulatory effects on macrophage-mediated immune responses against Pseudomonas aeruginosa (PA). Here, we use THP-1 and RAW264.7 cell lines and demonstrate that BD2 and BD3 suppressed macrophage autophagy but enhanced the engulfment of PA and Zymosan bioparticles as well as the formation of phagolysosomes, using immunofluorescence staining and confocal microscopy. Plate count assay showed that macrophage-mediated phagocytosis and intracellular killing of PA were promoted by BD2 and BD3. Furthermore, microarray and real-time PCR showed that the expression of two genes, early growth response gene-1 (EGR1) and c-FOS, was attenuated by BD2 and BD3. Western blot revealed that BD2 and BD3 inhibited the expression and nuclear translocation of EGR1 and c-FOS. Knockdown of EGR1 and c-FOS by siRNA transfection suppressed macrophage autophagy before and after PA infection; while overexpression of these two transcription factors enhanced autophagy but reversed the role of BD2 and BD3 on macrophage-mediated PA eradication. Together, these results demonstrate a novel immune defense activity of BD2 and BD3, which promotes clearance of PA by inhibiting macrophage autophagy through downregulation of EGR1 and c-FOS.


Assuntos
Autofagia/imunologia , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Macrófagos/imunologia , Proteínas Proto-Oncogênicas c-fos/metabolismo , Infecções por Pseudomonas/imunologia , Pseudomonas aeruginosa/imunologia , beta-Defensinas/imunologia , Animais , Núcleo Celular/metabolismo , Regulação para Baixo/imunologia , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/imunologia , Técnicas de Silenciamento de Genes , Humanos , Macrófagos/metabolismo , Camundongos , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/imunologia , Células RAW 264.7 , RNA Interferente Pequeno/metabolismo
12.
Cancer Invest ; 25(7): 527-34, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17952744

RESUMO

In this study, we evaluated antitumor effects of allotumour RNA-transfected dendritic cells (DCs) cocultured with autologous cytokine-induced killer cells (CIKs) on hormone-refractory prostate cancer. The cocultured cells enhanced prostate cancer cytolysis from 26% (CIKs-induced cytolysis) to 80.8%. They also increased the productions of CD4(+) Th1 (IFN-γ(+)IL-4(-), 55.52%) and CD8(+) T (IFN-γ(+), 69.59%) cells determined by intracellular cytokines IFN-γ /IL-4 staining and reduced the rate of CD4(+) CD25(+) cells from 18.72% (in CIKs) to 9.72%. The cocultured cells significantly inhibited tumor growth in SCID mouse and induced cancer cells necrosis and apoptosis. Our study indicates that tumor RNA-pulsed DCs cocultured with autologous CIKs significantly enhance antitumor immunity, which can be induced by increased CD4(+) Th1 and CD8(+) T cells and decreased CD4(+)CD25(+) regulatory T (T(reg)) cells. This provides a potential immunotherapy strategy for HRPC.


Assuntos
Antagonistas de Androgênios/farmacologia , Células Matadoras Induzidas por Citocinas/imunologia , Células Dendríticas/imunologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias da Próstata/terapia , RNA/imunologia , Animais , Linhagem Celular Tumoral , Proliferação de Células , Técnicas de Cocultura , Citotoxicidade Imunológica , Humanos , Masculino , Camundongos , Camundongos SCID , Transplante de Neoplasias , Transfecção
13.
Cell Mol Immunol ; 4(2): 113-20, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17484805

RESUMO

An adjuvant is usually used to enhance the immune response induced by vaccines. The choice of adjuvant or immune enhancer determines the effectiveness of the immune response. Currently, aluminium (Alum, a generic term for salts of aluminium) is the only FDA-approved adjuvant. Alum predominantly induces the differentiation of Th2 cells and thus mediates an antibody immune response. Therefore, there is an urgent need for new adjuvants that enhance not only humoral but also cellular immune responses. In the present study, we demonstrates that PIKA (a stabilized dsRNA) as an adjuvant directly induces the activation and the proliferation of both B and NK cells in vitro. Injection of PIKA into mice results in the production of cytokines in vivo. In addition, the study demonstrates that PIKA promotes the maturation of bone marrow-derived dendritic cells (BMDCs) including up-regulation of the co-stimulatory molecules CD80, CD86 and CD40, and the induction of cytokines such as IL-12p70, IL-12p40 and IL-6. Importantly, after immunization of mice with HBsAg plus PIKA, the presence of PIKA enhances the titers of HBsAg-specific IgG and HBsAg-specific IFN-gamma production. These results demonstrate that PIKA as an adjuvant can promote both humoral and cellular immune responses. These might have an implication in applying PIKA as an adjuvant to be used in the design and development of both therapeutic and preventive vaccines, and used in the clinical study.


Assuntos
Adjuvantes Imunológicos , Formação de Anticorpos , Antígenos de Superfície da Hepatite B/imunologia , Vacinas contra Hepatite B/imunologia , Imunidade Celular , RNA de Cadeia Dupla/imunologia , Vacinação , Animais , Antígenos CD/metabolismo , Linfócitos B/imunologia , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Diferenciação Celular/imunologia , Células Cultivadas , Citocinas/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Anticorpos Anti-Hepatite B/sangue , Células Matadoras Naturais/imunologia , Cinética , Ativação Linfocitária , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Regulação para Cima
14.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 24(2): 299-302, 2007 Apr.
Artigo em Zh | MEDLINE | ID: mdl-17591246

RESUMO

In this study, the peripheral blood mononuclear cells of healthy adult were acquired and inducted by vascular endothelial growth factor, et cetera. The differentiated endothelial cells were observed and identified as EPCs by the double positive staining of fluorescent labeled acetylated-LDL and lectin, seeded on the polyurethane small-diameter artificial vessels, treated by shear stress of 15 dyn/cm2, and observed by scanning electronic microscopy. As a result, the peripheral blood mononuclear cells differentiated into EPCs. They were positively stained by labeled acetylated-LDL and lectin. Under observation of scanning electronic microscope, the unseeded polyurethane small-diameter artificial vessel being suited for the growth and spreading of the cells; the cell lineage on surface of artificial vessels of stationary group being arrayed in chaos, and that of shear stress group being arrayed in direction. Therefore, the peripheral cells can differentiate into EPCs, and EPCs can be used as novel source cells for the accelerated endothelialization of small diameter artificial vessel. Shear stress contributes to the mechanic moulding of cell lineage on the surface of artificial vessel.


Assuntos
Órgãos Bioartificiais , Prótese Vascular , Células Endoteliais/citologia , Poliuretanos/química , Células-Tronco/citologia , Materiais Biocompatíveis , Adesão Celular , Diferenciação Celular , Células Cultivadas , Humanos , Leucócitos Mononucleares/citologia , Desenho de Prótese , Resistência ao Cisalhamento , Estresse Mecânico
15.
Mol Immunol ; 62(1): 29-36, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24937178

RESUMO

Macrophages play a critical role in the host immune response against mycobacterial infection. Our previous study has demonstrated that microRNA-155 (miR-155), one of the most important small non-coding RNAs in the immune system, promotes oxygen-independent mycobacterial killing in macrophages. However, little is known regarding the role of miR-155 in modulating oxygen-dependent mycobactericidal response in macrophages, including the production of reactive oxygen species (ROS) and reactive nitrogen species (RNS). In the present study, we demonstrated that miR-155 was increased in macrophages after Mycobacterium bovis bacille Calmette-Guérin (BCG) infection. Moreover, the BCG-induced upregulation of miR-155 in macrophages was dependent on TLR2, NF-κB and JNK signaling pathways. More importantly, our study explored that miR-155 significantly elevated ROS production in macrophages, although miR-155 had no influence on the inducible nitric oxide synthase (iNOS) expression or nitric oxide (NO) production. In addition, our study demonstrated that miR-155 repressed the expression of src homology 2 (SH2) containing inositol 5-phosphatase1 (SHIP1), and knockdown of SHIP1 greatly increased ROS production in BCG-infected macrophages. Collectively, these data indicate that miR-155 modulates ROS but not RNS production by targeting SHIP1, which may provide a better understanding of the host anti-mycobacterial response.


Assuntos
MicroRNAs/genética , Mycobacterium bovis/imunologia , Monoéster Fosfórico Hidrolases/genética , Espécies Reativas de Oxigênio/metabolismo , Tuberculose/imunologia , Animais , Células Cultivadas , Inositol Polifosfato 5-Fosfatases , Sistema de Sinalização das MAP Quinases , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/metabolismo , NF-kappa B/fisiologia , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases , Monoéster Fosfórico Hidrolases/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Receptor 2 Toll-Like/fisiologia , Regulação para Cima/genética
16.
J Infect ; 67(4): 329-41, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23685241

RESUMO

OBJECTIVES: To investigate the role of miR-146a in dengue virus (DENV) replication. METHODS: Expression levels of miR-146a were measured by real-time PCR and Northern blot. Role of miR-146a was tested by overexpression and inhibition assays. Real-time PCR and 50% tissue culture infective dose (TCID50) assays were used to detect RNA levels and extracellular yields of DENV respectively. Interferon (IFN) levels induced by DENV infection were measured by real-time PCR and ELISA respectively. IFN-ß neutralization and RNAi were used to test the involvement of IFN-ß in the effects of miR-146a. TNFR-associated factor 6 (TRAF6) level was measured by Western-blot. RESULTS: miR-146a expression was significantly increased in primary human monocytes and THP-1 cells upon DENV infection. Overexpression of miR-146a increased DENV2 replication, while inhibition of miR-146a decreased the viral replication. miR-146a impaired the IFN production and the DENV2 replication suppressed by miR-146a inhibition was partially restored by neutralization of IFN-ß or depletion of interferon receptor (IFNAR) 1 or 2. Furthermore, miR-146a targets TRAF6 and overexpression of TRAF6 reversed the effects of miR-146a on IFN-ß induction and viral replication. CONCLUSIONS: DENV infection significantly induced the expression of miR-146a, which facilitated viral replication by targeting TRAF6 and dampening IFN-ß production.


Assuntos
Vírus da Dengue/imunologia , Vírus da Dengue/fisiologia , Interferon beta/imunologia , MicroRNAs/metabolismo , Fator 6 Associado a Receptor de TNF/antagonistas & inibidores , Replicação Viral , Northern Blotting , Western Blotting , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Perfilação da Expressão Gênica , Humanos , Interferon beta/biossíntese , MicroRNAs/genética , Monócitos/imunologia , Monócitos/virologia , Reação em Cadeia da Polimerase em Tempo Real , Fator 6 Associado a Receptor de TNF/metabolismo
17.
Invest Ophthalmol Vis Sci ; 54(1): 804-12, 2013 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-23258145

RESUMO

PURPOSE: We investigated whether the foldable capsular vitreous body (FCVB) could release levofloxacin sustainably in vitro and inhibit endophthalmitis in rabbit models. METHODS: Approximately 1.0 mL levofloxacin (625 µg/mL) was injected into the capsule of nine FCVBS. The levofloxacin release value was determined in the modified franz diffusion cells over time. In the in vivo study, all right eyes of 45 rabbits were infected with Staphylococcus epidermidis AND were divided randomly into three groups at 24 hours after infection: FCVB plus levofloxacin (n = 15), silicone oil plus subconjunctival levofloxacin (n = 15), and an untreated group (n = 15) during a 30-day observation time. Levofloxacin concentrations in the aqueous humor were detected, and therapeutic efficacy was evaluated with clinical evaluation, bacterial counts, cytokine profiles, and histopathology. RESULTS: The FCVB released levofloxacin ranging from 9 to 13.5 ng/mL in vitro and from 42 to 1.6 ng/mL in the aqueous humor during 30 days. In the FCVB and silicone-treated groups, clinical inflammation almost was abolished; no bacteria were detected in the aqueous humor; TNF-α, IL-1ß, and IFN-γ expression decreased; and relatively normal corneal and retinal architecture were kept after the 30-day treatment. CONCLUSIONS: The FCVB could provide us with dual functions, combining a levofloxacin drug delivery system and a vitreous substitute, to treat endophthalmitis in rabbit eyes.


Assuntos
Antibacterianos/administração & dosagem , Sistemas de Liberação de Medicamentos , Endoftalmite/tratamento farmacológico , Infecções Oculares Bacterianas/tratamento farmacológico , Levofloxacino , Ofloxacino/administração & dosagem , Infecções Estafilocócicas/tratamento farmacológico , Corpo Vítreo , Animais , Corpo Ciliar/metabolismo , Contagem de Colônia Microbiana , Citocinas/genética , Implantes de Medicamento , Endoftalmite/genética , Endoftalmite/microbiologia , Infecções Oculares Bacterianas/genética , Infecções Oculares Bacterianas/microbiologia , Testes de Sensibilidade Microbiana , RNA Mensageiro/metabolismo , Coelhos , Reação em Cadeia da Polimerase em Tempo Real , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/microbiologia , Staphylococcus epidermidis/isolamento & purificação , Staphylococcus epidermidis/patogenicidade
18.
Artigo em Zh | MEDLINE | ID: mdl-22883581

RESUMO

OBJECTIVE: To investigate the differential expression of toll-like receptor 2 (TLR2), toll-like receptor 4 (TLR4) and their potential role in the pathogenesis of chronic suppurative otitis media and cholesteatoma. METHODS: Normal canal skin of 30 patients with tympanosclerosis were enrolled as control, 30 cases with chronic suppurative otitis media and 30 patients with cholesteatoma were studied. Real-time PCR, Western blot and Immunohistochemistry were preformed to detect the expression of TLR2/TLR4 in normal canal skin, mucosa and granulation tissue of chronic suppurative otitis media, mucosa, granulation tissue, cholesteatoma epithelium of cholesteatoma, and the differential expression were analyzed. RESULTS: (1) the mRNA and protein expression of TLR2 and TLR4 were detected in all normal canal skin, mucosa and granulation tissue of chronic suppurative otitis media, mucosa, granulation tissue, cholesteatoma epithelium of cholesteatoma. (2) Both mRNA and protein level of TLR2/TLR4 in mucosa of chronic suppurative otitis media and cholesteatoma were higher than those in normal canal skin, but lower in cholesteatoma epithelium, there was no significant difference in mucosa of the two otitis media groups. (3) The mRNA and protein expression of TLR2/TLR4 in granulation tissue of chronic suppurative otitis media and cholesteatoma were significant increased when compared with normal canal skin, and TLR2 expression level was higher in granulation tissue of cholesteatoma than in chronic suppurative otitis media. (4) TLR2/TLR4 positive cells mainly infiltrated in granulations, significantly more than in normal skin, while fewer in the epithelium of cholesteatoma. CONCLUSIONS: Differential expression of TLR2 and TLR4 in mucosa suggests middle ear is a TLR2/TLR4 participated functional modulation of the innate immune system and also suggests that they may play a different role in the pathophysiology of chronic otitis media and cholesteatoma.


Assuntos
Colesteatoma da Orelha Média/metabolismo , Otite Média Supurativa/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Estudos de Casos e Controles , Doença Crônica , Humanos
19.
PLoS One ; 6(8): e23346, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21829730

RESUMO

Toll-like receptors (TLRs) play an important role in innate immunity against invading pathogens. Although TLR signaling has been indicated to protect cells from infection of several viruses, the role of TLRs in Dengue virus (DENV) replication is still unclear. In the present study, we examined the replication of DENV serotype 2 (DENV2) by challenging hepatoma cells HepG2 with different TLR ligands. Activation of TLR3 showed an antiviral effect, while pretreatment of other TLR ligands (including TLR1/2, TLR2/6, TLR4, TLR5 or TLR7/8) did not show a significant effect. TLR3 ligand poly(I:C) treatment prior to viral infection or simultaneously, but not post-treatment, significantly down-regulated virus replication. Pretreatment with poly(I:C) reduced viral mRNA expression and viral staining positive cells, accompanying an induction of the type I interferon (IFN-ß) and type III IFN (IL-28A/B). Intriguingly, neutralization of IFN-ß alone successfully restored the poly(I:C)-inhibited replication of DENV2. The poly(I:C)-mediated effects, including IFN induction and DENV2 suppression, were significantly reversed by IKK inhibitor, further suggesting that IFN-ß is the dominant factor involved in the poly(I:C) mediated antiviral effect. Our study presented the first evidence to show that activation of TLR3 is effective in blocking DENV2 replication via IFN-ß, providing an experimental clue that poly(I:C) may be a promising immunomodulatory agent against DENV infection and might be applicable for clinical prevention.


Assuntos
Carcinoma Hepatocelular/patologia , Vírus da Dengue/fisiologia , Interferon beta/biossíntese , Neoplasias Hepáticas/patologia , Receptor 3 Toll-Like/fisiologia , Replicação Viral/fisiologia , Sequência de Bases , Linhagem Celular Tumoral , Primers do DNA , Vírus da Dengue/genética , Humanos , Ligantes , Microscopia de Fluorescência , Poli I-C/farmacologia , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Receptor 3 Toll-Like/metabolismo
20.
Artigo em Zh | MEDLINE | ID: mdl-18826099

RESUMO

OBJECTIVE: To investigate the effect of garlicin on the levels of interferon gamma (INF-gamma) and interleukin 4 (IL-4) in blood of allergic rhinitis rat model. METHODS: Thirty healthy female SD rats were randomly divided into 3 groups: control group, negative control group and experimental group, 10 rats for each group. Ten rats (experimental group) were sensitized and intranasally challenged by ovalbumin, aluminium hydroxide hydrate gel and Bordetella pertussis inactive microorganism suspension adjuvants, as allergic rhinitis models, and then injection of garlicin(0.4 ml) intraperitoneally per day for 10 days. Control group rats were immunized as experimental group, and then injection of physiological saline as equal volume as garlicin. Negative control group rats were investigated using physiological saline. Blood of intrajugular vein of rat was extracted for separated plasma Enzyme liked immunosorbent assay (ELISA) was utilized to detect the serum levels of IL-4 and IFN-gamma. RESULTS: The serum levels (x +/- s) of IL4 were (22.81 +/- 8.79) pg/L, (41.43 +/- 4.93) pg/L, (9.93 +/- 2.07) pg/L, and those of IFN-gamma were (22.32 +/- 11.20) pg/L, (11.35 +/- 2.45) pg/L and (21.69 +/- 5.93) pg/L, respectively, among experimental group, control group and negative control group. The serum level of IL-4 in experimental group rats was lower than value of control group rats (t = 3.22, P < 0.05), while higher than negative control group (t = 4.17, P < 0.05). The serum level of IFN-gamma was increased significantly in experimental group rats with significant difference when compared with value of control group rats (t = 3.84, P < 0.05), while no difference was shown between experimental group and negative control group (t = 1.47, P > 0.05). CONCLUSIONS: Garlicin could increase serum level of INF-gamma and decrease serum level of IL4 significantly in allergic rhinitis rat model. It played an important role on regulating serum levels of cytokines of Thl and Th2.


Assuntos
Compostos Alílicos/farmacologia , Dissulfetos/farmacologia , Interferon gama/sangue , Interleucina-4/sangue , Rinite Alérgica Sazonal/sangue , Animais , Modelos Animais de Doenças , Feminino , Ratos , Ratos Sprague-Dawley , Células Th1/efeitos dos fármacos , Células Th2/efeitos dos fármacos
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