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1.
Adv Sci (Weinh) ; 10(18): e2207526, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37088787

RESUMO

Amorphous metal oxide semiconductor phototransistors (MOTPs) integrated with colloidal quantum dots (QDs) (QD-MOTPs) are promising infrared photodetectors owing to their high photoconductive gain, low off-current level, and high compatibility with pixel circuits. However, to date, the poor mobility of conventional MOTPs, such as indium gallium zinc oxide (IGZO), and the toxicity of lead (Pb)-based QDs, such as lead sulfide and lead selenide, has limited the commercial applications of QD-MOTPs. Herein, an ultrasensitive QD-MOTP fabricated by integrating a high-mobility zinc oxynitride (ZnON)-based MOTP and lead-free indium arsenide (InAs) QDs is demonstrated. A new gradated bandgap structure is introduced in the InAs QD layer that absorbs infrared light, which prevents carriers from moving backward and effectively reduces electron-hole recombination. Chemical, optical, and structural analyses confirm the movement of the photoexcited carriers in the graded band structure. The novel QD-MOTP exhibits an outstanding performance with a responsivity of 1.15 × 105 A W-1 and detectivity of 5.32 × 1016 Jones at a light power density of 2 µW cm-2 under illumination at 905 nm.


Assuntos
Pontos Quânticos , Índio , Zinco , Óxidos
2.
J Appl Microbiol ; 133(1): 67-75, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34688224

RESUMO

AIMS: To investigate anti-inflammatory effects of Lactobacillus reuteri LM1071 in lipopolysaccharides (LPS)-induced inflammation RAW264.7 cells. METHODS AND RESULTS: To evaluate anti-inflammatory activities of L. reuteri LM1071, LPS-stimulated RAW264.7 cells were used. Gene expression levels of eight immune-associated genes including IL-1ß, IL-6 and TNF-α and protein production levels of COX-1 and COX-2 were analysed. Moreover, the production of eicosanoids as important biomarkers for anti-inflammation was determined. CONCLUSIONS: The current study demonstrates that L. reuteri LM1071 has anti-inflammatory potential by inhibiting the production of inflammation mediators such as NO, eicosanoids such as PGE1 & PGE2, pro-inflammatory cytokines and COX proteins. It can also enhance the production of inflammatory associated genes such as IL-11, BMP4, LEFTY2 and EET metabolite. SIGNIFICANCE AND IMPACT OF THE STUDY: Lactobacillus reuteri is one of the crucial bacteria for food fermentation. It can be found in the gastrointestinal system of human and animals. Several studies have shown that L. reuteri has valuable effects on host health. The current study firstly demonstrated that L. reuteri has a beneficial effect on the inflammation containing the variation of eicosanoids (PGE1 and PGE2) which are one of the most important biomarkers and moreover eicosanoid-associated genes as well as proteins (COX-2).


Assuntos
Limosilactobacillus reuteri , Alprostadil/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Ciclo-Oxigenase 2/uso terapêutico , Dinoprostona/metabolismo , Dinoprostona/uso terapêutico , Humanos , Inflamação/tratamento farmacológico , Limosilactobacillus reuteri/metabolismo , Fatores de Determinação Direita-Esquerda , Lipopolissacarídeos/farmacologia , Camundongos , Células RAW 264.7
3.
Exp Mol Med ; 53(1): 67-80, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33408335

RESUMO

Histamine releasing factor/translationally controlled tumor protein (HRF/TCTP) stimulates cancer progression and allergic responses, but the role of HRF/TCTP in rheumatoid arthritis (RA) remains undefined. In this study, we explored the pathogenic significance of HRF/TCTP and evaluated the therapeutic effects of HRF/TCTP blockade in RA. HRF/TCTP transgenic (TG) and knockdown (KD) mice with collagen-induced arthritis (CIA) were used to determine the experimental phenotypes of RA. HRF/TCTP levels in the sera of RA patients were measured and compared to those from patients with osteoarthritis (OA), ankylosing spondylitis, Behçet's disease, and healthy controls. HRF/TCTP expression was also assessed in the synovium and fibroblast-like synoviocytes (FLSs) obtained from RA or OA patients. Finally, we assessed the effects of HRF/TCTP and dimerized HRF/TCTP-binding peptide-2 (dTBP2), an HRF/TCTP inhibitor, in RA-FLSs and CIA mice. Our clinical, radiological, histological, and biochemical analyses indicate that inflammatory responses and joint destruction were increased in HRF/TCTP TG mice and decreased in KD mice compared to wild-type littermates. HRF/TCTP levels in the sera, synovial fluid, synovium, and FLSs were higher in patients with RA than in control groups. Serum levels of HRF/TCTP correlated well with RA disease activity. The tumor-like aggressiveness of RA-FLSs was exacerbated by HRF/TCTP stimulation and ameliorated by dTBP2 treatment. dTBP2 exerted protective and therapeutic effects in CIA mice and had no detrimental effects in a murine tuberculosis model. Our results indicate that HRF/TCTP is a novel biomarker and therapeutic target for the diagnosis and treatment of RA.


Assuntos
Artrite Experimental/metabolismo , Artrite Reumatoide/metabolismo , Fibroblastos/metabolismo , Sinoviócitos/metabolismo , Proteína Tumoral 1 Controlada por Tradução/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Células Cultivadas , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Oligopeptídeos/farmacologia , Oligopeptídeos/uso terapêutico , Ligação Proteica , Proteína Tumoral 1 Controlada por Tradução/antagonistas & inibidores , Proteína Tumoral 1 Controlada por Tradução/genética
4.
J Med Food ; 23(8): 852-861, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32513044

RESUMO

In this study, we explored whether the use of Streptococcus thermophilus LM1012 (TL-LM1012) as a safe probiotic exerts hepatoprotective effects by suppressing oxidative stress and inflammation in vitro and alleviating aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) production in vivo. In a series of safety tests, TL-LM1012 was found to have a negative response to hemolysis and biogenic amines, as well as susceptibility to antibiotics. TL-LM1012 protected cell viability and suppressed cytotoxicity by inhibiting oxidative stress and induced heme oxygenase-1 and superoxide dismutase activity in a dose-dependent manner in diesel exhaust particulate matter (DEPM)-treated HepG2 cells. Moreover, proinflammatory cytokines, including tumor necrosis factor-α, interleukin (IL)-6, and IL-1ß, were suppressed in DEPM-treated splenocytes. In DEPM-treated mice, oral administration of TL-LM1012 regulated AST, ALT, and LDH production in the serum after 14 days of treatment. These findings indicate that TL-LM1012, a safe probiotic, provides a potent preventive or therapeutic effect against liver disease caused by air pollution.


Assuntos
Poluentes Atmosféricos/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Probióticos/uso terapêutico , Streptococcus thermophilus , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Citocinas , Células Hep G2 , Humanos , Fígado/metabolismo , Fígado/microbiologia , Camundongos , Estresse Oxidativo , Material Particulado/toxicidade , Emissões de Veículos/toxicidade
5.
J Anim Sci Technol ; 62(6): 864-874, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33987566

RESUMO

Lactic acid bacteria are well-known probiotics, conferring several health benefits. In this study, we isolated lactobacilli from human breast milk and identified Lactobacillus reuteri LM1071 (RR-LM1071) using 16S rDNA sequencing. We tested the hemolytic activity, biogenic amine production, and antibiotic susceptibility of this strain to assess its safety. RR-LM1071 was found to be negative for hemolytic activity and biogenic amine production, as well as was measured in susceptible level for antibiotics in the minimal inhibitory concentration (MIC) test. The adhesive properties of RR-LM1071 were higher than those of LGG in HT-29 cells, and showed a greater hydrophobicity than LGG in hexadecane solvent. Under inflammatory conditions, RR-LM1071 suppressed the mRNA expression of IL-6, TNF-α, and IL-4 produced in IL-1ß-induced HT-29 cells. Our results suggest that RR-LM1071 is a safe and valuable probiotic that can be used for the treatment of inflammatory bowel disease.

6.
Appl Spectrosc ; 74(2): 210-222, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31680543

RESUMO

Tunable diode laser absorption spectroscopy (TDLAS) technology is a developing method for temperature and species concentration measurements with the features of non-contact, high precision, high sensitivity, etc. The difficulty of two-dimensional (2D) temperature measurement in actual combustors has not yet been solved because of pressure broadening of absorption spectra, optical accessibility, etc. In this study, the combination of computed tomography (CT) and TDLAS with a wide scanning laser at 1335-1375 nm has been applied to a combustor for 2D temperature measurement in high temperature of 300-2000 K and high pressure of 0.1-2.5 MPa condition. An external cavity type laser diode with wide wavelength range scanning at 1335-1375 nm was used to evaluate the broadened H2O absorption spectra due to the high-temperature and high-pressure effect. The spectroscopic database in high temperature of 300-2000 K and high pressure of 0.1-5.0 MPa condition has been revised to improve the accuracy for temperature quantitative analysis. CT reconstruction accuracy was also evaluated in different cases, which presented the consistent temperature distribution between CT reconstruction and assumed distributions. The spatial and temporal distributions of temperature in the high-temperature and high-pressure combustor were measured successfully by CT-TDLAS using the revised spectroscopic database.

7.
J Med Food ; 22(9): 896-906, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31216204

RESUMO

The present study investigated the immunomodulatory activity and associated mechanisms of heat-treated Lactobacillus plantarum LM1004 (HT-LM1004) in a cyclophosphamide (CTX)-induced mouse model of immunosuppression. HT-LM1004 induced phagocytic activity and nitric oxide production in RAW264.7 macrophages and stimulated the release of tumor necrosis factor (TNF)-α, interferon (IFN)-γ, interleukin (IL)-2, and IL-12p70. In mice with CTX-induced immunosuppression, oral HT-LM1004 administration restored thymus and spleen indices, including spleen weight. Consistent with the in vitro results, HT-LM1004 increased TNF-α, IFN-γ, IL-2, and IL-12p70 levels in mice after 14 days of treatment and enhanced the natural killer (NK) cell activity of splenocytes from mice with CTX-induced immunosuppression against YAC-1 lymphoma cells. The method of HT-LM1004 generation influenced this activity: L. plantarum LM1004 grown in a membrane bioreactor, which reduced the size of the cells to <1.0 µm through physical stress (micronization), promoted NK cell cytotoxicity to a greater extent than LM1004 subjected to heat treatment alone. These findings indicate that HT-LM1004 without or with micronization can reverse CTX-induced immunosuppression without adverse side effects by potentiating NK cell function.


Assuntos
Antineoplásicos Alquilantes/efeitos adversos , Ciclofosfamida/efeitos adversos , Fatores Imunológicos/administração & dosagem , Imunomodulação/efeitos dos fármacos , Lactobacillus plantarum/química , Probióticos/administração & dosagem , Animais , Antineoplásicos Alquilantes/administração & dosagem , Ciclofosfamida/administração & dosagem , Feminino , Temperatura Alta , Terapia de Imunossupressão , Interferon gama/genética , Interferon gama/imunologia , Interleucina-12/genética , Interleucina-12/imunologia , Interleucina-2/genética , Interleucina-2/imunologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Fagocitose/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
8.
Inflammation ; 40(6): 1825-1835, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28819701

RESUMO

The purpose of this study is to investigate the effect of TSAHC [4'-(p-toluenesulfonylamido)-4-hydroxychalcone] in K/BxN serum transfer arthritis model and fibroblast-like synoviocytes of rheumatoid arthritis (RA-FLS). In in vivo experiments, TSAHC attenuated the incidence and severity of arthritis in comparison with the vehicle group. Histological findings showed that TSAHC decreased the inflammation, bone erosion, cartilage damage, and osteoclasts activity in the ankle. Furthermore, we confirmed by biochemical analysis that the observations were associated with the decreased expression of proinflammatory cytokines, matrix metalloproteinases (MMPs), and RANKL in serum and ankle. In in vitro experiments, TSAHC induced apoptosis, while it significantly suppressed tumor necrosis factor-α (TNF-α)-induced cell proliferation in RA-FLS. Moreover, TSAHC inhibited mRNA expression of TNF-α-induced interleukin (IL)-6, MMP-1, MMP-3, and MMP-13. Evaluation of signaling events showed that TSAHC inhibited the translocation and transcriptional activity of nuclear factor-kappa B (NF-κB) by regulating phosphorylated-IκB-α (p-IκB-α) and IκB-α in TNF-α-induced RA-FLS. Our results suggest that TSAHC inhibits experimental arthritis in mice and suppresses TNF-α-induced RA-FLS activities via NF-κB pathway. Therefore, TSAHC may have therapeutic potential for the treatment of RA.


Assuntos
Artrite Experimental/tratamento farmacológico , Chalcona/análogos & derivados , Sulfonamidas/farmacologia , Sinoviócitos/patologia , Animais , Artrite Experimental/patologia , Proliferação de Células/efeitos dos fármacos , Chalcona/farmacologia , Fibroblastos , Camundongos , NF-kappa B/metabolismo , Sinoviócitos/efeitos dos fármacos , Fator de Necrose Tumoral alfa/antagonistas & inibidores
9.
Exp Mol Med ; 48: e221, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26987484

RESUMO

The type III histone deacetylase silent information regulator 1 (SIRT1) is an enzyme that is critical for the modulation of immune and inflammatory responses. However, the data on its role in rheumatoid arthritis (RA) are limited and controversial. To better understand how SIRT1 regulates adaptive immune responses in RA, we evaluated collagen-induced arthritis (CIA) in myeloid cell-specific SIRT1 knockout (mSIRT1 KO) and wild-type (WT) mice. Arthritis severity was gauged on the basis of clinical, radiographic and pathologic scores. Compared with their WT counterparts, the mSIRT1 KO mice exhibited less severe arthritis, which was less destructive to the joints. The expression levels of inflammatory cytokines, matrix metalloproteinases and ROR-γT were also reduced in the mSIRT1 KO mice compared with the WT mice and were paralleled by reductions in the numbers of Th1 and Th17 cells and CD80- or CD86-positive dendritic cells (DCs). In addition, impaired DC maturation and decreases in the Th1/Th17 immune response were observed in the mSIRT1 KO mice. T-cell proliferation was also investigated in co-cultures with antigen-pulsed DCs. In the co-cultures, the DCs from the mSIRT1 KO mice showed decreases in T-cell proliferation and the Th1/Th17 immune response. In this study, myeloid cell-specific deletion of SIRT1 appeared to suppress CIA by modulating DC maturation. Thus, a careful investigation of DC-specific SIRT1 downregulation is needed to gauge the therapeutic utility of agents targeting SIRT1 in RA.


Assuntos
Artrite Experimental/etiologia , Artrite Experimental/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Deleção de Genes , Células Mieloides/metabolismo , Sirtuína 1/genética , Animais , Artrite Experimental/diagnóstico , Diferenciação Celular , Técnicas de Cocultura , Citocinas/genética , Citocinas/metabolismo , Células Dendríticas/citologia , Modelos Animais de Doenças , Regulação da Expressão Gênica , Humanos , Mediadores da Inflamação/metabolismo , Linfonodos/imunologia , Linfonodos/metabolismo , Camundongos , Camundongos Knockout , NF-kappa B/metabolismo , Sinovite/genética , Sinovite/imunologia , Sinovite/metabolismo , Sinovite/patologia , Células Th1/citologia , Células Th1/imunologia , Células Th1/metabolismo , Células Th17/citologia , Células Th17/imunologia , Células Th17/metabolismo , Fator de Transcrição AP-1/metabolismo
10.
J Nutr Biochem ; 26(7): 713-20, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25910895

RESUMO

It is suggested that n-3 polyunsaturated fatty acids (PUFAs) can be used in the preventive or therapeutic management of rheumatoid arthritis (RA); however, controversial results have been reported. Here, we examined the effects of a decrease in the n-6/n-3 PUFA ratio on RA using fat-1 transgenic mice. First, we tested whether fat-1 expression modulated signaling pathways in fibroblast-like synoviocytes (FLSs) stimulated with tumor necrosis factor α (TNF-α). TNF-α activated p38 mitogen-activated protein kinase and increased phosphorylation of the signal transducer and activator of transcription 3 in wild type (WT) FLSs but not in fat-1 FLSs. Arthritis was induced by injection of K/BxN serum. Based on clinical scores, ankle thickness and pathological severity, we showed that WT mice developed clinically overt arthritis, whereas fat-1 mice showed attenuated arthritis. Moreover, fat-1 mice exhibited down-regulated local and systemic levels of inflammatory cytokines. Lastly, bone marrow-derived macrophages (BMMs) of WT mice differentiated into tartrate-resistant acid phosphatase-positive multinucleated osteoclasts, whereas the osteoclastogenenic process was suppressed in BMMs of fat-1 mice. The endogenous conversion of n-6 to n-3 PUFAs via fat-1 plays a key role in attenuation of RA; therefore, dietary supplementation of n-3 PUFAs may have therapeutic potential for the management of RA.


Assuntos
Artrite Experimental/prevenção & controle , Artrite Reumatoide/prevenção & controle , Proteínas de Caenorhabditis elegans/metabolismo , Ácidos Graxos Dessaturases/metabolismo , Ácidos Graxos Ômega-3/metabolismo , Ácidos Graxos Ômega-6/metabolismo , Membrana Sinovial/metabolismo , Animais , Antirreumáticos/metabolismo , Antirreumáticos/uso terapêutico , Artrite Experimental/dietoterapia , Artrite Experimental/metabolismo , Artrite Experimental/patologia , Artrite Reumatoide/dietoterapia , Artrite Reumatoide/metabolismo , Artrite Reumatoide/patologia , Proteínas de Caenorhabditis elegans/genética , Células Cultivadas , Gorduras Insaturadas na Dieta/metabolismo , Gorduras Insaturadas na Dieta/uso terapêutico , Suplementos Nutricionais , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Ômega-3/uso terapêutico , Humanos , Interleucina-6/metabolismo , Sistema de Sinalização das MAP Quinases , Camundongos Transgênicos , Fosforilação , Processamento de Proteína Pós-Traducional , Proteínas Recombinantes/metabolismo , Fator de Transcrição STAT3/metabolismo , Membrana Sinovial/citologia , Membrana Sinovial/imunologia , Membrana Sinovial/patologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
11.
J Biol Chem ; 280(31): 28775-84, 2005 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-15941719

RESUMO

Although biochemical properties of 2-Cys peroxiredoxins (Prxs) have been extensively studied, their real physiological functions in higher eukaryotic cells remain obscure and certainly warrant further study. Here we demonstrated that human (h) PrxII, a cytosolic isotype of human 2-Cys Prx, has dual functions as a peroxidase and a molecular chaperone, and that these different functions are closely associated with its adoption of distinct protein structures. Upon exposure to oxidative stress, hPrxII assumes a high molecular weight complex structure that has a highly efficient chaperone function. However, the subsequent removal of stressors induces the dissociation of this protein structure into low molecular weight proteins and triggers a chaperone-to-peroxidase functional switch. The formation of a high molecular weight hPrxII complex depends on the hyperoxidation of its N-terminal peroxidatic Cys residue as well as on its C-terminal domain, which contains a "YF motif" that is exclusively found in eukaryotic 2-Cys Prxs. A C-terminally truncated hPrxII exists as low and oligomeric protein species and does not respond to oxidative stress. Moreover, this C-terminal deletion of hPrxII converted it from an oxidation-sensitive to a hyperoxidation-resistant form of peroxidase. When functioning as a chaperone, hPrxII protects HeLa cells from H(2)O(2)-induced cell death, as measured by a terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling assay and fluorescence-activated cell sorting analysis.


Assuntos
Morte Celular/efeitos dos fármacos , Resistência a Medicamentos , Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo/fisiologia , Peroxidases/metabolismo , Citosol/enzimologia , Células HeLa , Humanos , Isoenzimas/metabolismo , Cinética , Chaperonas Moleculares/metabolismo , Peroxirredoxinas
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