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1.
Part Fibre Toxicol ; 20(1): 33, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37605240

RESUMO

BACKGROUND: Nanodiamonds (NDs) have gained a rapidly growing interest in biomedical applications; however, little is known regarding their biokinetics owing to difficulties in measurements and limited synthesis/purification technologies. In this study, we investigated the distribution kinetics of detonation-synthesized NDs in mice via intravenous injection to evaluate the parameters that determine the behavior of the particles. We prepared two distinctive NDs that controlled the sp3/sp2 carbon ratio and particle size by coating them with serum proteins. The four control samples were intravenously injected into mice, and tissue distribution and clearance were evaluated at 30 min and 1, 7, and 28 days post-injection. RESULTS: The sp3/sp2 carbon ratio showed no correlation with the organ distribution of the NDs. However, hydrodynamic size showed an excellent correlation with organ distribution levels: a negative correlation in the liver and positive correlations in the spleen and lungs. Furthermore, the deposition levels of NDs in the lung suggest that particles smaller than 300 nm could avoid lung deposition. Finally, a similar organ distribution pattern was observed in mice injected with carbon black nanoparticles controlled hydrodynamic size. CONCLUSIONS: In conclusion, the tissue distribution of NDs is modulated not by the sp3/sp2 carbon ratio but by the hydrodynamic size, which can provide helpful information for targeting the tissue of NDs. Furthermore, the organ distribution pattern of the NDs may not be specific to NDs but also can apply to other nanoparticles, such as carbon black.


Assuntos
Hidrodinâmica , Nanodiamantes , Animais , Camundongos , Injeções Intravenosas , Cinética , Fuligem , Distribuição Tecidual , Carbono
2.
Int J Med Sci ; 18(2): 432-440, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33390812

RESUMO

Prevotella nigrescens is an oral pathogen that is frequently observed in the subgingival plaque of periodontitis patients. Interleukin-1ß (IL-1ß) is known to be involved in the immunopathology of periodontal diseases and has been implicated in the destruction of bone. In this study, we investigated the mechanism of IL-1ß production by P. nigrescens in murine bone marrow-derived dendritic cells (BMDCs). Our results showed that a host receptor, Toll-like receptor 2 (TLR2), but not TLR4 is required for pro-IL-1ß induction and nucleotide-binding oligomerization domain like receptor pyrin domain containing 3 (NLRP3) priming in BMDCs in response to P. nigrescens and activation of the NLRP3 inflammasome is necessary for processing of pro-IL-1ß into mature IL-1ß. In addition, an inhibitor assay revealed that production of reactive oxygen species, P2X7R activity, and release of cathepsin B are involved in IL-1ß production in BMDCs in response to P. nigrescens.


Assuntos
Infecções por Bactérias Gram-Negativas/imunologia , Interleucina-1beta/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Periodontite/imunologia , Prevotella nigrescens/imunologia , Receptor 2 Toll-Like/metabolismo , Animais , Catepsina B/metabolismo , Células Cultivadas , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Modelos Animais de Doenças , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Inflamassomos/imunologia , Inflamassomos/metabolismo , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Periodontite/microbiologia , Cultura Primária de Células , Espécies Reativas de Oxigênio/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Receptor 2 Toll-Like/genética
3.
Small ; 15(52): e1905076, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31778013

RESUMO

Surface-enhanced Raman scattering (SERS) is one of the most promising methods to detect small molecules for point-of-care analysis as it is rapid, nondestructive, label-free, and applicable for aqueous samples. Here, microgels containing highly concentrated yet evenly dispersed gold nanoparticles are designed to provide SERS substrates that simultaneously achieve contamination-free metal surfaces and high signal enhancement and reproducibility. With capillary microfluidic devices, water-in-oil-in-water (W/O/W) double-emulsion drops are prepared to contain gold nanoparticles and hydrogel precursors in innermost drop. Under hypertonic condition, water is selectively pumped out from the innermost drops. Therefore, gold nanoparticles are gently concentrated without forming aggregates, which are then captured by hydrogel matrix. The resulting microgels have a concentration of gold nanoparticles ≈30 times higher and show Raman intensity two orders of magnitude higher than those with no enrichment. In addition, even distribution of gold nanoparticles results in uniform Raman intensity, providing high signal reproducibility. Moreover, as the matrix of the microgel serves as a molecular filter, large adhesive proteins are rejected, which enables the direct detection of small molecules dissolved in the protein solution. It is believed that this advanced SERS platform is useful for in situ detection of toxic molecules in complex mixtures such as biological fluids, foods, and cosmetics.

4.
Small ; 14(40): e1802520, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30129114

RESUMO

Surface-enhanced Raman scattering (SERS) provides a dramatic increase of Raman intensity for molecules adsorbed on nanogap-rich metal nanostructures, serving as a promising tool for molecular analysis. However, surface contamination caused by protein adsorption and low surface concentration of small target molecules reduce the sensitivity, which severely restricts the use of SERS in many applications. Here, charged microgels containing agglomerates of gold nanoparticles (Au NPs) are designed using droplet-based microfluidics to provide a reliable SERS substrate with molecular selectivity and high sensitivity. The limiting mesh size of hydrogel enables the autonomous exclusion of large proteins and the charged matrix concentrates oppositely charged small molecules through electrostatic attraction. As nanogaps among Au NPs in the agglomerates enhance Raman intensity, Raman spectrum of the adsorbed molecules is selectively measured with high sensitivity in the absence of interruption from adhesive proteins. Therefore, the SERS-active-charged microgels can be used for direct analysis of pristine biological samples without the pretreatment steps of separation and concentration, which are commonly a prerequisite for Raman analysis. For the purpose of demonstration, a direct detection of fipronil sulfone with partial negative charges, a metabolite of toxic insecticide, dissolved in eggs using the positively charged microgels without any pretreatment of the samples, is shown.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Microfluídica/métodos , Análise Espectral Raman/métodos , Eletricidade Estática
5.
Immunology ; 150(4): 495-505, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28032341

RESUMO

Acinetobacter baumannii is a multi-drug resistant, Gram-negative bacteria and infection with this organism is one of the major causes of mortality in intensive care units. Inflammasomes are multiprotein oligomers that include caspase-1, and their activation is required for maturation of interleukin-1ß (IL-1ß). Inflammasome signalling is involved in host defences against various microbial infections, but the precise mechanism by which A. baumannii activates inflammasomes and the roles of relevant signals in host defence against pulmonary A. baumannii infection are unknown. Our results showed that NLRP3, ASC and caspase-1, but not NLRC4, are required for A. baumannii-induced production of IL-1ß in macrophages. An inhibitor assay revealed that various pathways, including P2X7R, K+ efflux, reactive oxygen species production and release of cathepsins, are involved in IL-1ß production in macrophages in response to A. baumannii. Interleukin-1ß production in bronchoalveolar lavage (BAL) fluid was impaired in NLRP3-deficient and caspase-1/11-deficient mice infected with A. baumannii, compared with that in wild-type (WT) mice. However, the bacterial loads in BAL fluid and lungs were comparable between WT and NLRP3-deficient or caspase-1/11-deficient mice. The severity of lung pathology was reduced in NLRP3- deficient, caspase-1/11- deficient and IL-1-receptor-deficient mice, although the recruitment of immune cells and production of inflammatory cytokines and chemokines were not altered in these mice. These findings indicate that A. baumannii leads to the activation of NLRP3 inflammasome, which mediates IL-1ß production and lung pathology.


Assuntos
Infecções por Acinetobacter/imunologia , Acinetobacter baumannii/imunologia , Interleucina-1beta/metabolismo , Pulmão/imunologia , Macrófagos/fisiologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Pneumonia/imunologia , Animais , Caspase 1/genética , Caspase 1/metabolismo , Caspases/genética , Caspases/metabolismo , Caspases Iniciadoras , Células Cultivadas , Humanos , Inflamassomos/metabolismo , Interleucina-1beta/genética , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/genética
6.
Small ; 13(23)2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28464428

RESUMO

Surface-enhanced Raman scattering (SERS) is a promising technique for molecular analysis as the molecular fingerprints (Raman spectra) are amplified to detectable levels compared with common spectroscopy. Metal nanostructures localize electromagnetic field on their surfaces, which can lead to dramatic increase of Raman intensity of molecules adsorbed. However, the metal surfaces are prone to contamination, thereby requiring pretreatment of samples to remove adhesive molecules. To avoid the pretreatment and potentially achieve point-of-care (POC) analysis, we have developed SERS-active microgels using the droplet-microfluidic system. As the microgels are composed of water-swollen network with consistent mesh size, they selectively allow diffusion of molecules smaller than the mesh, thereby excluding large adhesives. To render the microgels highly SERS-active, we destabilize silver nanocubes to form agglomerates, which are embedded in the matrix of microgels. The nanogaps in the agglomerates provide high sensitivity in Raman measurement and size-selective permeability of the microgel matrix obviates the pretreatment of samples. To validate the functions, we demonstrate the direct detection of Aspirin dissolved in whole blood without any pretreatment.

7.
Nano Lett ; 16(3): 1890-5, 2016 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-26839956

RESUMO

Heterostructures of compositionally and electronically variant two-dimensional (2D) atomic layers are viable building blocks for ultrathin optoelectronic devices. We show that the composition of interfacial transition region between semiconducting WSe2 atomic layer channels and metallic NbSe2 contact layers can be engineered through interfacial doping with Nb atoms. WxNb1-xSe2 interfacial regions considerably lower the potential barrier height of the junction, significantly improving the performance of the corresponding WSe2-based field-effect transistor devices. The creation of such alloyed 2D junctions between dissimilar atomic layer domains could be the most important factor in controlling the electronic properties of 2D junctions and the design and fabrication of 2D atomic layer devices.

8.
Infect Immun ; 84(1): 172-86, 2016 01.
Artigo em Inglês | MEDLINE | ID: mdl-26502906

RESUMO

Shiga toxin (Stx)-mediated immune responses, including the production of the proinflammatory cytokines tumor necrosis-α (TNF-α) and interleukin-1ß (IL-1ß), may exacerbate vascular damage and accelerate lethality. However, the immune signaling pathway activated in response to Stx is not well understood. Here, we demonstrate that enzymatically active Stx, which leads to ribotoxic stress, triggers NLRP3 inflammasome-dependent caspase-1 activation and IL-1ß secretion in differentiated macrophage-like THP-1 (D-THP-1) cells. The treatment of cells with a chemical inhibitor of glycosphingolipid biosynthesis, which suppresses the expression of the Stx receptor globotriaosylceramide and subsequent endocytosis of the toxin, substantially blocked activation of the NLRP3 inflammasome and processing of caspase-1 and IL-1ß. Processing and release of both caspase-1 and IL-1ß were significantly reduced or abolished in Stx-intoxicated D-THP-1 cells in which the expression of NLRP3 or ASC was stably knocked down. Furthermore, Stx mediated the activation of caspases involved in apoptosis in an NLRP3- or ASC-dependent manner. In Stx-intoxicated cells, the NLRP3 inflammasome triggered the activation of caspase-8/3, leading to the initiation of apoptosis, in addition to caspase-1-dependent pyroptotic cell death. Taken together, these results suggest that Stxs trigger the NLRP3 inflammasome pathway to release proinflammatory IL-1ß as well as to promote apoptotic cell death.


Assuntos
Proteínas de Transporte/imunologia , Caspase 1/imunologia , Interleucina-1beta/biossíntese , Piroptose/imunologia , Toxinas Shiga/imunologia , Proteínas Adaptadoras de Sinalização CARD/genética , Proteínas Adaptadoras de Sinalização CARD/imunologia , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/imunologia , Proteínas de Transporte/genética , Caspase 1/genética , Caspase 3/imunologia , Caspase 8/imunologia , Linhagem Celular Tumoral , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/imunologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Ativação Enzimática/imunologia , Glicoesfingolipídeos/biossíntese , Humanos , Inflamação/imunologia , Interleucina-1beta/imunologia , Interleucina-1beta/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR , Interferência de RNA , RNA Interferente Pequeno , Escherichia coli Shiga Toxigênica/metabolismo , Transdução de Sinais/imunologia , Triexosilceramidas/biossíntese , Fator de Necrose Tumoral alfa/imunologia
9.
J Oral Pathol Med ; 45(4): 262-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26332444

RESUMO

OBJECTIVES: Microbial Pattern-recognition receptors (PRRs), such as nucleotide-binding oligomerization domains (NODs), are essential for mammalian innate immune response. This study was designed to determine the effect of NOD1 and NOD2 agonist on innate immune responses and antitumor activity in oral squamous cell carcinoma (OSCC) cells. MATERIALS AND METHODS: NODs expression was examined by RT-PCR, and IL-8 production by NODs agonist was examined by ELISA. Western blot analysis was performed to determine the MAPK activation in response to their agonist. Cell proliferation was determined by MTT assay. Flow cytometry and Western blot analysis were performed to determine the MDP-induced cell death. RESULTS: The levels of NODs were apparently expressed in OSCC cells. NODs agonist, Tri-DAP and MDP, led to the production of IL-8 and MAPK activation. NOD2 agonist, MDP, inhibited the proliferation of YD-10B cells in a dose-dependent manner. Also, the ratio of Annexin V-positive cells and cleaved PARP was increased by MDP treatment in YD-10B cells, suggesting that MDP-induced cell death in YD-10B cells may be owing to apoptosis. CONCLUSIONS: Our results indicate that NODs are functionally expressed in OSCC cells and can trigger innate immune responses. In addition, NOD2 agonist inhibited cell proliferation and induced apoptosis. These findings provide the potential value of MDP as novel candidates for antitumor agents of OSCC.


Assuntos
Acetilmuramil-Alanil-Isoglutamina/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/tratamento farmacológico , Ácido Diaminopimélico/análogos & derivados , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias Bucais/tratamento farmacológico , Proteína Adaptadora de Sinalização NOD2/agonistas , Oligopeptídeos/farmacologia , Antineoplásicos/farmacologia , Apoptose/fisiologia , Western Blotting , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Ácido Diaminopimélico/farmacologia , Neoplasias de Cabeça e Pescoço/imunologia , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Imunidade Inata/efeitos dos fármacos , Interleucina-8/biossíntese , Interleucina-8/metabolismo , Proteínas Quinases Ativadas por Mitógeno/biossíntese , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias Bucais/imunologia , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Proteína Adaptadora de Sinalização NOD1/agonistas , Proteína Adaptadora de Sinalização NOD1/biossíntese , Proteína Adaptadora de Sinalização NOD1/genética , Proteína Adaptadora de Sinalização NOD2/biossíntese , Proteína Adaptadora de Sinalização NOD2/genética , RNA Mensageiro/biossíntese , Carcinoma de Células Escamosas de Cabeça e Pescoço
10.
Am J Orthod Dentofacial Orthop ; 149(3): 391-400, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26926027

RESUMO

INTRODUCTION: This study was performed to investigate the cephalometric configuration of the occlusal plane in patients with anterior open bite. METHODS: Of 61 subjects with open bite (overbite ≥3.75 mm) who had been recruited consecutively from January 2006 to November 2013 and had no history of orthodontic treatment, 14 cephalometric landmarks indicating the incisal edge or the buccal or mesiobuccal cusp tips of each tooth were used for K-means clustering to classify the occlusal plane configuration. For the open-bite group and a control group with normal occlusion (n = 38), dentoalveolar height, which is the perpendicular distance of each tooth to the palatal or mandibular plane, was compared among the clusters and between the 2 groups. RESULTS: The open-bite subjects were divided into 2 clusters according to occlusal contact of the premolars: Y-form and V-form (with and without premolar contact, respectively). The normalized dentoalveolar heights of the 4 mandibular teeth (lateral incisor to second premolar) were significantly greater in the Y-form class than in the V-form class. The dentoalveolar heights of the 5 maxillary teeth (lateral incisor to first molar) were significantly greater in the open-bite group than in the control group. CONCLUSIONS: For anterior open-bite treatment, the cephalometric configuration of the occlusal plane should be considered based on the occlusal contacts of the premolars.


Assuntos
Cefalometria/métodos , Mordida Aberta/patologia , Coroa do Dente/patologia , Adulto , Processo Alveolar/patologia , Pontos de Referência Anatômicos/patologia , Dente Pré-Molar/patologia , Cefalometria/estatística & dados numéricos , Análise por Conglomerados , Dente Canino/patologia , Arco Dental/patologia , Oclusão Dentária , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Incisivo/patologia , Masculino , Mandíbula/patologia , Dente Molar/patologia , Palato/patologia , Adulto Jovem
11.
J Toxicol Pathol ; 29(2): 95-102, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27182113

RESUMO

Although several animal models have been developed to study human pulmonary fibrosis, lack of a perfect model has raised the need for various animal models of pulmonary fibrosis. In this study, we evaluated the pulmonary effect of polyhexamethyleneguanidine phosphate instillation into the lungs of mice to determine the potential of these mice as a murine model of pulmonary fibrosis. Intratracheal instillation of polyhexamethyleneguanidine phosphate induced severe lung inflammation manifested by the infiltration of mononuclear cells and neutrophils and increased production of IL-6, TNF-α, CCL2 and CXCL1. The lung inflammation gradually increased until 28 days after polyhexamethyleneguanidine phosphate exposure, and increases of collagen deposition and TGF-ß production, which are indicators of pulmonary fibrosis, were seen. Our study showed that intratracheal instillation of polyhexamethyleneguanidine phosphate induces pulmonary inflammation and fibrosis in mice.

12.
Cytokine ; 71(2): 139-44, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25461391

RESUMO

As a potent immune regulator, heat shock protein 70 derived from Mycobacterium tuberculosis (Mtb Hsp70) has adjuvant effect and activates immune cells such as macrophages and dendritic cells (DCs). Although Toll-like receptors (TLRs) are known to involve in DCs activation by Mtb Hsp70, there is still a controversy and the underlying mechanism is not well understood. In this study, we examined whether TRIF and MyD88, the core adaptor molecules for TLRs signaling, regulate Mtb Hsp70-induced DCs activation. Although Mtb Hsp70 produced substantial level of cytokines (IL-6, IL-12p40, and TNF-α) in TRIF-deficient DCs in a dose-dependent manner, each level was significantly lower than that in WT cells. The cytokines production was almost abolished in MyD88-deficient DCs. Consistent with cytokine results, Mtb Hsp70-induced activation of NF-κB and MAPKs was also impaired in both TRIF- and MyD88-deficient DCs, as compared with WT cells. Inhibitor assay revealed that NF-κB, ERK, and JNK, but not p38, regulate Mtb Hsp70-induced production of cytokines. In addition, the up-regulation of co-stimulatory molecules and MHC class II was mostly TRIF-dependent in DCs in response Mtb Hsp70, whereas MyD88 was only partially involved. Finally, mixed leukocytes reaction (MLR) assay revealed that both TRIF and MyD88 are critical for DCs ability promoted by Mtb Hsp70 to differentiate naïve T cells into effector T cells of producing IFN-γ. Our findings suggest that both TRIF and MyD88 are essential for the activation and maturation of DCs in response to Mtb Hsp70.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/imunologia , Proteínas de Bactérias/imunologia , Células Dendríticas/imunologia , Proteínas de Choque Térmico HSP70/imunologia , Fator 88 de Diferenciação Mieloide/imunologia , Proteínas Adaptadoras de Transporte Vesicular/deficiência , Proteínas Adaptadoras de Transporte Vesicular/genética , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/farmacologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Células Cultivadas , Técnicas de Cocultura , Citocinas/imunologia , Citocinas/metabolismo , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/farmacologia , Interferon gama/imunologia , Interferon gama/metabolismo , Teste de Cultura Mista de Linfócitos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/metabolismo , Fator 88 de Diferenciação Mieloide/deficiência , Fator 88 de Diferenciação Mieloide/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/farmacologia , Linfócitos T/imunologia , Linfócitos T/metabolismo
13.
Infect Immun ; 82(5): 1914-20, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24566622

RESUMO

Toll-like receptors (TLRs) orchestrate a repertoire of immune responses in macrophages against various pathogens. Fusobacterium nucleatum and Aggregatibacter actinomycetemcomitans are two important periodontal pathogens. In the present study, we investigated TLR signaling regulating cytokine production of macrophages in response to F. nucleatum and A. actinomycetemcomitans. TLR2 and TLR4 are redundant in the production of cytokines (interleukin-6 [IL-6] and tumor necrosis factor alpha [TNF-α]) in F. nucleatum- and A. actinomycetemcomitans-infected macrophages. The production of cytokines by macrophages in response to F. nucleatum and A. actinomycetemcomitans infection was impaired in MyD88-deficient macrophages. Moreover, cytokine concentrations were lower in MyD88-deficient macrophages than in TLR2/TLR4 (TLR2/4) double-deficient cells. An endosomal TLR inhibitor, chloroquine, reduced cytokine production in TLR2/4-deficient macrophages in response to F. nucleatum and A. actinomycetemcomitans, and DNA from F. nucleatum or A. actinomycetemcomitans induced IL-6 production in bone marrow-derived macrophages (BMDMs), which was abolished by chloroquine. Western blot analysis revealed that TLR2/4 and MyD88 were required for optimal activation of NF-κB and mitogen-activated protein kinases (MAPKs) in macrophages in response to F. nucleatum and A. actinomycetemcomitans, with different kinetics. An inhibitor assay showed that NF-κB and all MAPKs (p38, extracellular signal-regulated kinase [ERK], and Jun N-terminal protein kinase [JNK]) mediate F. nucleatum-induced production of cytokines in macrophages, whereas NF-κB and p38, but not ERK and JNK, are involved in A. actinomycetemcomitans-mediated cytokine production. These findings suggest that multiple TLRs may participate in the cytokine production of macrophages against periodontal bacteria.


Assuntos
Aggregatibacter actinomycetemcomitans/fisiologia , Citocinas/metabolismo , Fusobacterium nucleatum/fisiologia , Macrófagos/metabolismo , Receptores Toll-Like/metabolismo , Animais , Citocinas/genética , Infecções por Fusobacterium/imunologia , Infecções por Fusobacterium/metabolismo , Infecções por Fusobacterium/microbiologia , Regulação da Expressão Gênica/fisiologia , Camundongos , Camundongos Knockout , Infecções por Pasteurellaceae/imunologia , Infecções por Pasteurellaceae/metabolismo , Infecções por Pasteurellaceae/microbiologia , Receptores Toll-Like/genética
14.
Immunology ; 143(2): 269-76, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24766550

RESUMO

Nod-like receptors are a family of innate immune receptors that link cytosolic sensing of microbial and danger stimuli to the activation of immune responses. Two Nod-like receptor family members, Nod1 and Nod2, recognize bacterial peptidoglycan and activate immune responses via nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK). The function of Nod1 and Nod2 has been largely studied in macrophages, but the role of these receptors in other innate immune cells remains unclear. In this study, we examined the function of Nod1 and Nod2 in innate immune responses of neutrophils. Mice were injected intraperitoneally with thioglycollate, and then peritoneal neutrophils were isolated 4 hr after injection. Tri-DAP and muramyl-dipeptide (MDP) were used as Nod1 and Nod2 agonists, respectively. The level of cytokines [interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α)] and chemokines (CXCL1 and CCL2) was increased by MDP, but not Tri-DAP in wild-type (WT) neutrophils. Increased production of cytokines and chemokines with MDP was abolished in Nod2- and Rip2-deficient neutrophils. MDP also induced the activation of NF-κB and MAPK in WT neutrophils, but not in Nod2- and Rip2-deficient cells. Flow cytometry analysis showed that L-selectin shedding was induced by MDP in WT neutrophils, but not in Nod2- and Rip2-deficient cells. MDP and Toll-like receptor (TLR) agonists (Pam3 CSK4 and lipopolysaccharide) exerted synergistic effects on the production of IL-6 and CXCL1 in neutrophils. Moreover, Nod2 and TLR4 cooperated to produce IL-6, TNF-α, CXCL1 and CCL2 in neutrophils in response to Gram-negative bacteria. Our findings suggest that the Nod2-Rip2 axis may contribute to the innate immune response of neutrophils against bacterial infection.


Assuntos
Imunidade Inata , Ativação de Neutrófilo , Neutrófilos/imunologia , Proteína Adaptadora de Sinalização NOD2/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Acetilmuramil-Alanil-Isoglutamina/farmacologia , Animais , Células Cultivadas , Quimiocina CCL2/metabolismo , Quimiocina CXCL1/metabolismo , Ácido Diaminopimélico/análogos & derivados , Ácido Diaminopimélico/farmacologia , Imunidade Inata/efeitos dos fármacos , Interleucina-6/metabolismo , Selectina L/metabolismo , Lipopolissacarídeos/farmacologia , Listeria monocytogenes/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Ativação de Neutrófilo/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Neutrófilos/microbiologia , Proteína Adaptadora de Sinalização NOD1/agonistas , Proteína Adaptadora de Sinalização NOD1/metabolismo , Proteína Adaptadora de Sinalização NOD2/agonistas , Proteína Adaptadora de Sinalização NOD2/deficiência , Proteína Adaptadora de Sinalização NOD2/genética , Oligopeptídeos/farmacologia , Proteína Serina-Treonina Quinase 2 de Interação com Receptor , Proteína Serina-Treonina Quinases de Interação com Receptores/deficiência , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Transdução de Sinais , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Yersinia pseudotuberculosis/imunologia
15.
Eur J Immunol ; 43(10): 2650-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23818043

RESUMO

Helicobacter pylori colonization of the stomach affects about half of the world population and is associated with the development of gastritis, ulcers, and cancer. Polymorphisms in the IL1B gene are linked to an increased risk of H. pylori associated cancer, but the bacterial and host factors that regulate interleukin (IL)-1ß production in response to H. pylori infection remain unknown. Using murine BM-derived DCs, we show that the bacterial virulence factors cytotoxin-associated genes pathogenicity island and CagL, but not vacuolating cytotoxin A or CagA, regulate the induction of pro-IL-1ß and the production of mature IL-1ß in response to H. pylori infection. We further show that the host receptors, Toll-like receptor 2 (TLR2) and nucleotide-binding oligomerization domain 2 (NOD2), but not NOD1, are required for induction of pro-IL-1ß and NOD-like receptor pyrin domain containing 3 (NLRP3) in H. pylori infected DCs. In contrast, NLRP3 and the adaptor ASC were essential for the activation of caspase-1, processing of pro-IL-1ß into IL-1ß, and IL-1ß secretion. Finally, we show that mice deficient in caspase-1, IL-1ß, and IL-1 receptor, but not NLRP3, are impaired in the clearance of CagA-positive H. pylori from the stomach when compared with WT mice. These studies identify bacterial cag pathogenicity island and the cooperative interaction among host innate receptors TLR2, NOD2, and NLRP3 as important regulators of IL-1ß production in H. pylori infected DCs.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas de Transporte/metabolismo , Células Dendríticas/imunologia , Ilhas Genômicas , Infecções por Helicobacter/imunologia , Helicobacter pylori/patogenicidade , Proteína Adaptadora de Sinalização NOD2/metabolismo , Receptor 2 Toll-Like/metabolismo , Animais , Antígenos de Bactérias/metabolismo , Carga Bacteriana , Proteínas de Transporte/genética , Células Dendríticas/microbiologia , Regulação da Expressão Gênica/genética , Imunidade Inata/genética , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR , Proteína Adaptadora de Sinalização NOD2/genética , Receptor 2 Toll-Like/genética , Virulência/genética
16.
Helicobacter ; 19(6): 476-83, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25231285

RESUMO

BACKGROUND: Although Helicobacter pylori have been known to induce vascular endothelial growth factor (VEGF) production in gastric epithelial cells, the precise mechanism for cellular signaling is incompletely understood. In this study, we investigated the role of bacterial virulence factor and host cellular signaling in VEGF production of H. pylori-infected gastric epithelial cells. MATERIALS AND METHODS: We evaluated production of VEGF, activation of nuclear factor nuclear factor-kappaB (NF-κB) and mitogen-activated protein kinases (MAPKs) and hypoxia-inducible factor-1α (HIF-1α) stabilization in gastric epithelial cells infected with H. pylori WT or isogenic mutants deficient in type IV secretion system (T4SS). RESULTS: H. pylori induced VEGF production in gastric epithelial cells via both T4SS-dependent and T4SS-independent pathways, although T4SS-independent pathway seems to be the dominant signaling. The inhibitor assay implicated that activation of NF-κB and MAPKs is dispensable for H. pylori-induced VEGF production in gastric epithelial cells. H. pylori led to HIF-1α stabilization in gastric epithelial cells independently of T4SS, NF-κB, and MAPKs, which was essential for VEGF production in these cells. N-acetyl-cysteine (NAC), a reactive oxygen species (ROS) inhibitor, treatment impaired H. pylori-induced HIF-1α stabilization and VEGF production in gastric epithelial cells. CONCLUSION: We defined the important role of ROS-HIF-1α axis in VEGF production of H. pylori-infected gastric epithelial cells, and bacterial T4SS has a minor role in H. pylori-induced VEGF production of gastric epithelial cells.


Assuntos
Células Epiteliais/metabolismo , Infecções por Helicobacter/metabolismo , Helicobacter pylori/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sistemas de Secreção Bacterianos , Células Epiteliais/microbiologia , Mucosa Gástrica/metabolismo , Infecções por Helicobacter/genética , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , NF-kappa B/metabolismo , Transdução de Sinais , Estômago/citologia , Estômago/microbiologia , Fator A de Crescimento do Endotélio Vascular/genética
18.
Prostate ; 72(12): 1351-8, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22228081

RESUMO

BACKGROUND: Nod1 and Nod2 are cytosolic receptors which are responsible for sensing bacterial peptidoglycan derivatives. In this study, we determined whether Nod1 and Nod2 are involved in the innate immune responses of prostate epithelial cells. METHODS: The expression of Nod1 and Nod2 was examined by RT-PCR and immunohistochemistry. ELISA was performed to determine the production of cytokines/chemokines. Activation of NF-κB and MAPK was examined using western blot analysis. RESULTS: The Nod1 gene was distinctly expressed in all tested cells including DU145, PC3, and TRAMP-C2 cells, whereas Nod2 expression was weak. Both Nod1 and Nod2 proteins were expressed in normal mouse prostate epithelia with difference of expression levels. Tri-DAP (Nod1 agonist), but not MDP (Nod2), increased the production of IL-8 (or KC) and IL-6 in prostate epithelial cells. Tri-DAP and MDP could upregulate the gene expression of COX-2 and activate NF-κB and MAPK. In addition, Tri-DAP and MDP synergized with TLR agonists to induce the production of IL-8/KC or IL-6 in PC3 and TRAMP-C2 cells. We finally showed that Nod1 and Nod2 were also expressed in a wide range of prostate lesions including prostate intraepithelial neoplasm (PIN), phyllodes-like tumor, and adenocarcinoma in TRAMP (transgenic adenocarcinoma of the mouse prostate) mice, even though the expression level of Nod1 and Nod2 was different. CONCLUSION: These results indicate that Nod1 and Nod2 may play important roles in the innate immune response of prostate epithelial cells and the development and progression of prostate cancer.


Assuntos
Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Imunidade Inata , Proteína Adaptadora de Sinalização NOD1/metabolismo , Proteína Adaptadora de Sinalização NOD2/metabolismo , Próstata/imunologia , Próstata/metabolismo , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/metabolismo , Adenocarcinoma/imunologia , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Linhagem Celular Tumoral , Progressão da Doença , Células Epiteliais/citologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína Adaptadora de Sinalização NOD1/fisiologia , Proteína Adaptadora de Sinalização NOD2/fisiologia , Próstata/citologia , Neoplasias da Próstata/patologia
19.
Acta Derm Venereol ; 92(5): 467-71, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22113882

RESUMO

The aims of this study were to evaluate the prevalence, severity and risk factors for atopic dermatitis in Korean pre-school children as determined by dermatological examination vs questionnaire survey. A total of 6,453 pre-school children from 59 kindergartens and 14 day-care centres were evaluated. Parents responded to an International Study of Asthma and Allergies in Childhood (ISAAC)-based questionnaire containing questions concerning 23 risk factors, as well as the prevalence, and severity of atopic dermatitis. Fourteen dermatologists then examined the participants according to the Korean diagnostic criteria for atopic dermatitis, and the Eczema Area and Severity Index (EASI) score. Atopic dermatitis prevalence determined by dermatological examination was lower than the questionnaire-based prevalence (9.2% vs 19.1%). Most patients (96.2%) had mild atopic dermatitis according to the EASI score (mean ± SD 3.91 ± 4.73; median 1.5; range 0.2-38.0). However, 17.4% had sleep disturbance, and 56.7% had not obtained complete remission of their rash over the previous 12 months. Among the 12 risk factors, "changing the patient's house to a newly built house during the first year of life" had significant odds ratio. In conclusion, the prevalence of atopic dermatitis in Korea in the ISAAC-based survey conducted by paediatricians was similar to that in several European countries, and lower than the 2006 Korean figure (28.9%). In addition, the prevalence of atopic dermatitis was lower when assessed by dermatological examination than by questionnaire.


Assuntos
Povo Asiático , Dermatite Atópica/etnologia , Distribuição por Idade , Fatores Etários , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Estudos Transversais , Dermatite Atópica/diagnóstico , Dermatite Atópica/patologia , Feminino , Inquéritos Epidemiológicos , Habitação , Humanos , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Razão de Chances , Prevalência , Prognóstico , República da Coreia/epidemiologia , Características de Residência , Fatores de Risco , Índice de Gravidade de Doença , Pele/patologia , Transtornos do Sono-Vigília/etnologia , Inquéritos e Questionários
20.
ACS Synth Biol ; 11(5): 1719-1726, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35502843

RESUMO

Controlling translational elongation is essential for efficient protein synthesis. Ribosome profiling has revealed that the speed of ribosome movement is correlated with translational efficiency in the translational elongation ramp. In this work, we present a new deep learning model, called DeepTESR, to predict the degree of translational elongation short ramp (TESR) from mRNA sequence. The proposed deep learning model exhibited superior performance in predicting the TESR scores for 226 981 TESR sequences, resulting in the mean absolute error (MAE) of 0.285 and a coefficient of determination R2 of 0.627, superior to the conventional machine learning models (e.g., MAE of 0.335 and R2 of 0.571 for LightGBM). We experimentally validated that heterologous fluorescence expression of proteins with randomly selected TESR was moderately correlated with the predictions. Furthermore, a genome-wide analysis of TESR prediction in the 4305 coding sequences of Escherichia coli showed conserved TESRs over the clusters of orthologous groups. In this sense, DeepTESR can be used to predict the degree of TESR for gene expression control and to decipher the mechanism of translational control with ribosome profiling. DeepTESR is available at https://github.com/fmblab/DeepTESR.


Assuntos
Aprendizado Profundo , Escherichia coli/genética , Escherichia coli/metabolismo , Elongação Traducional da Cadeia Peptídica/genética , Biossíntese de Proteínas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ribossomos/genética , Ribossomos/metabolismo
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