RESUMO
Label-free biosensors provide an important platform for detecting chemical and biological substances without needing extra labeling agents. Unlike surface-based techniques such as surface plasmon resonance (SPR), interference, and ellipsometry, surface-enhanced Raman spectroscopy (SERS) possesses the advantage of monitoring analytes both on surfaces and in solutions. Increasing the SERS enhancement is crucial to preparing high-quality substrates without quickly losing their stability, sensitivity, and repeatability. However, fabrication methods based on wet chemistry, nanoimprint lithography, spark discharge, and laser ablation have drawbacks of waste of time, complicated processes, or nonreproducibility in surface topography. This study reports the preparation of recyclable TiO2/Ag nanoparticle (AgNP) substrates by using simple arc ion plating and direct-current (dc) magnetron sputtering technologies. The deposited anatase-phased TiO2 ensured the photocatalytic degradation of analytes. By measuring the Raman spectra of rhodamine 6G (R6G) in titrated concentrations, a limit of detection (LOD) of 10-8 M and a SERS enhancement factor (EF) of 1.01 × 109 were attained. Self-cleaning was performed via UV irradiation, and recyclability was achieved after at least five cycles of detection and degradation. The proposed TiO2/AgNP substrates have the potential to serve as eco-friendly SERS enhancers for label-free detection of various chemical and biological substances.
Assuntos
Nanopartículas Metálicas , Prata , Nanopartículas Metálicas/química , Prata/química , Análise Espectral Raman/métodos , Titânio/químicaRESUMO
In the context of industry 4.0, building data clouds in manufacturing technologies is the fundamental step to approach intelligent automatic process. This new technology has proved to efficiently and effectively monitor five important responses (removal rate, texture, surface accuracy, edge-profiles and mid-spatial frequencies) with more than 95% repeatability in real time. This faster and inexpensive process can serve for the nowadays high-quality segmented telescopes. We illustrate the underlying problem by reference to a case-study - the challenge of an average manufacturing rate of 11.4 segments per month for the 39.3m optical/infrared European Extremely Large Telescope (E-ELT) project.
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Diabetes is associated with hyperglycemia and increased thrombin production. However, it is unknown whether a combination of high glucose and thrombin can modulate the expression of NAPDH oxidase (Nox) subtypes in human aortic endothelial cells (HAECs). Moreover, we investigated the role of a diabetes-associated microRNA (miR-146a) in a diabetic atherothrombosis model. We showed that high glucose (HG) exerted a synergistic effect with thrombin to induce a 10.69-fold increase in Nox4 mRNA level in HAECs. Increased Nox4 mRNA expression was associated with increased Nox4 protein expression and ROS production. Inflammatory cytokine kit identified that the treatment increased IL-8 and IL-6 levels. Moreover, HG/thrombin treatment caused an 11.43-fold increase of THP-1 adhesion to HAECs. In silico analysis identified the homology between miR-146a and the 3'-untranslated region of the Nox4 mRNA, and a luciferase reporter assay confirmed that the miR-146a mimic bound to this Nox4 regulatory region. Additionally, miR-146a expression was decreased to 58% of that in the control, indicating impaired feedback restraint of HG/thrombin-induced endothelial inflammation. In contrast, miR-146a mimic transfection attenuated HG/thrombin-induced upregulation of Nox4 expression, ROS generation, and inflammatory phenotypes. In conclusion, miR-146a is involved in the regulation of endothelial inflammation via modulation of Nox4 expression in a diabetic atherothrombosis model.
Assuntos
Glucose/farmacologia , Inflamação/induzido quimicamente , MicroRNAs/genética , NADPH Oxidases/metabolismo , Trombina/farmacologia , Western Blotting , Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Linhagem Celular , Humanos , Monócitos/citologia , Monócitos/efeitos dos fármacos , NADPH Oxidase 4 , NADPH Oxidases/genética , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Pseudaminic acid (Pse) on pathogenic bacteria exopolysaccharide engages with the sialic acid-binding immunoglobulin-type lectin (Siglec)-10 receptor on macrophages via the critical 7-N-acetyl group. This binding stimulates macrophages to secrete interleukin 10 that suppresses phagocytosis against bacteria, but can be reverted by blocking Pse-Siglec-10 interaction with Pse-binding protein as a promising therapy.
Assuntos
Interleucina-10 , Macrófagos , Açúcares Ácidos , Interleucina-10/metabolismo , Macrófagos/metabolismo , Fagocitose/fisiologia , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/metabolismoRESUMO
Alkali metal halides have long been used as scintillators for applications as sensors and detectors. Usually, a small amount of impurities are added to these inorganic materials to improve their luminescence efficiencies. We investigate the structures and luminescent properties of un-doped sodium iodide (NaI) and cesium-doped NaI (NaI:Cs) films deposited by thermal vacuum evaporation. Instead of using the toxic element thallium (Tl), we introduced cesium dopant into NaI. This is the first study for the NaI:Cs film excited by UV LED's ultraviolet C (273 nm, 4.54 eV). The luminescence spectra show two main peaks at 3.05 and 4.32/3.955 eV (for fused silica/B270 substrate), originating from the intrinsic defects and/or activator excited states and the intrinsic self-trapped excitons (STEs), respectively. In general, both Cs-doping and post-annealing processes enhance the luminescence performance of NaI films.
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Highly reflective metal coatings are essential for manufacturing reflecting telescope mirrors to achieve the highest reflectivity with broad spectral bandwidth. Among metallic materials, enhanced silver-based coatings can provide higher reflectivity in the 400-500 nm spectral range to better performance from visible to near IR. Moreover, over-coating a dielectric protective layer on the mirror's front side attains additional hardness and oxidation stability. In this paper, we study a combination of thermal and electron beam evaporation as a technology to form protected enhanced high reflective Ag coatings. A newly designed multiplayer film can pass ASTM 5B adhesive performance testing and give sulfurization inhibition. The average specular reflectivity for the enhancement coating is about 98% in wavelengths across the spectral range from 400-1000 nm. This innovation has been demonstrated on a Newtonian type telescope, with storage in an ambiance humidity H = 60-85%, and temperature T = 10-35 °C, for more than six months without degradation in coating performance.
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Surface-enhanced Raman spectroscopy (SERS) is commonly used for super-selective analysis through nanostructured silver layers in the environment, food quality, biomedicine, and materials science. To fabricate a high-sensitivity but a more accessible device of SERS, DC magnetron sputtering technology was used to realize high sensitivity, low cost, a stable deposition rate, and rapid mass production. This study investigated various thicknesses of a silver film ranging from 3.0 to 12.1 nm by field emission scanning electron microscope, X-ray diffraction, and X-ray photoelectron spectroscopy. In the rhodamine 6G (R6G) testing irradiated by a He-Ne laser beam, the analytical enhancement factor (AEF) of 9.35 × 108, the limit of detection (LOD) of 10-8 M, and the relative standard deviation (RSD) of 1.61% were better than the other SERS substrates fabricated by the same DC sputtering process because the results showed that the 6 nm thickness silver layer had the highest sensitivity, stability, and lifetime. The paraquat and acetylcholine analytes were further investigated and high sensitivity was also achievable. The proposed SERS samples were evaluated and stored in a low humidity environment for up to forty weeks, and no spectrum attenuation could be detected. Soon, the proposed technology to fabricate high sensitivity, repeatability, and robust SERS substrate will be an optimized process technology in multiple applications.
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BACKGROUND: Despite recent advances in understanding the pathophysiology of cancer cachexia, prevention/treatment of this debilitating disease remains an unmet medical need. METHODS: We developed an integrated, multi-tiered strategy involving both in vitro and in vivo muscle atrophy platforms to identify traditional Chinese medicine (TCM)-based anti-cachectic agents. In the initial screening, we used inflammatory cytokine-induced atrophy of C2C12 myotubes as a phenotypic screening platform to assess the protective effects of TCMs. The selected TCMs were then evaluated for their abilities to protect Caenorhabditis elegans from age-related reduction of mobility and contractility, followed by the C-26 colon adenocarcinoma mouse model of cachexia to confirm the anti-muscle atrophy effects (body/skeletal muscle weights, fibre size distribution, grip strengths, and serum IL-6). Transcriptome analysis, quantitative real-time polymerase chain reaction, and immunoblotting were performed to gain understanding of the potential mechanism(s) by which effective TCM protected against C26 tumour-induced muscle atrophy. RESULTS: Of 29 widely used TCMs, Dioscorea radix (DR) and Mu Dan Pi (MDP) showed a complete protection (all P values, 0.0002) vis-à-vis C26 conditioned medium control in the myotube atrophy platform. MDP exhibited a unique ability to ameliorate age-associated decreases in worm mobility, accompanied by improved total body contractions, relative to control (P < 0.0001 and <0.01, respectively), which, however, was not noted with DR. This differential in vivo protective effect between MDP and DR was also confirmed in the C-26 mouse model. MDP at 1000 mg/kg (MDP-H) was effective in protecting body weight loss (P < 0.05) in C-26 tumour-bearing mice without changing food or water intake, accompanied by the restoration of the fibre size distribution of hindleg skeletal muscles (P < 0.0001) and the forelimb grip strength (P < 0.05). MDP-treated C-26-tumour-bearing mice were alert, showed normal posture and better body conditions, and exhibited lower serum IL-6 levels (P = 0.06) relative to vehicle control. This decreased serum IL-6 was associated with the in vitro suppressive effect of MDP (25 and 50 µg/mL) on IL-6 secretion into culture medium by C26 cells. RNA-seq analysis, followed by quantitative real-time polymerase chain reaction and/or immunoblotting, shows that MDP's anti-cachectic effect was attributable to its ability to reverse the C-26 tumour-induced re-programming of muscle homoeostasis-associated gene expression, including that of two cachexia drivers (MuRF1 and Atrogin-1), in skeletal muscles. CONCLUSIONS: All these findings suggest the translational potential of MDP to foster new strategies for the prevention and/or treatment of cachexia. The protective effect of MDP on other types of muscle atrophy such as sarcopenia might warrant investigations.
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Adenocarcinoma , Neoplasias do Colo , Adenocarcinoma/patologia , Animais , Caquexia/etiologia , Caquexia/genética , Linhagem Celular Tumoral , Neoplasias do Colo/metabolismo , Modelos Animais de Doenças , Interleucina-6 , Medicina Tradicional Chinesa , Camundongos , Atrofia Muscular/patologiaRESUMO
BACKGROUND: African Swine Fever (ASF) is a highly contagious and lethal viral disease of swine, the presence of which in groups of pigs leads to enormous economic losses in the farming industry. However, vaccines and drugs to treat ASF have yet to be developed. To control the spread of the African Swine Fever Virus (ASFV), a diagnostic method that can be applied rapidly and can detect the disease during the early stages of infection is urgently needed. METHODS: In this study, we demonstrate a rapid and easy-to-use ASFV detection method that combines loop-mediated isothermal amplification (LAMP) and image processing with the hue-saturation-value (HSV) color model. This method was validated through use of synthetic ASFV DNA. RESULTS: The method shows high sensitivity, as it detects as few as 10 copies per reaction within 20 min. The speed and sensitivity of this newly developed assay are superior to those reported in previous studies. In addition, through HSV color space transformation, the colorimetric result of this LAMP assay can be used for a semi-quantitative analysis for ASFV (ranging from 108 to 101 copies per reaction) and improve the discern to low concentration samples from a negative control. CONCLUSION: These results show that the combination of ASFV-LAMP assay and HSV color space transformation may accelerate the screening process of pigs for ASFV infection. Overall, this study provides a rapid, sensitive, early-stage, on-site diagnosis of ASFV infection and has potential to be applied to other infectious diseases.
Assuntos
Vírus da Febre Suína Africana/isolamento & purificação , Febre Suína Africana/diagnóstico , Colorimetria/veterinária , Técnicas de Diagnóstico Molecular/veterinária , Técnicas de Amplificação de Ácido Nucleico/veterinária , Vírus da Febre Suína Africana/genética , Animais , Proteínas do Capsídeo/genética , Telefone Celular , Simulação por Computador , DNA Viral/genética , Sensibilidade e Especificidade , SuínosRESUMO
Relative to several other p21-activated kinase (PAK) family members, the role of PAK3 in regulating cancer cell functions remains unclear. Our study obtained evidence that PAK3 regulates the Akt-GSK3ß-ß-catenin signaling by acting as Ser473-Akt kinase in several pancreatic cancer cell lines. Specifically, knockdown of PAK3 or overexpression of dominant-negative PAK3 inhibited the phosphorylation of Ser473-Akt and GSK3ß, resulting in the proteasomal degradation of ß-catenin. Conversely, overexpression of PAK3 led to activation of Akt signaling and increased ß-catenin expression. These changes, however, were not noted with the silencing and/or overexpression of PAK1, PAK2, or PAK4, which underlies the impetus of PAK3 as a key effector in governing malignant phenotypes in these pancreatic cancer cells, including cancer stem cell (CSC) expansion. Accordingly, PAK3 depletion effectively suppresses tumorsphere formation, ALDH activity, and the expression of CSC surface markers. Moreover, we used a stable knockdown clone of AsPC-1â¯cells to demonstrate the in vivo efficacy of PAK3 inhibition in suppressing tumorigenesis and xenograft tumor growth. Together, these findings suggest the potential role of PAK3 as a target for pancreatic cancer therapy, which warrants further investigations.
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Proliferação de Células , Glicogênio Sintase Quinase 3 beta/metabolismo , Células-Tronco Neoplásicas/enzimologia , Neoplasias Pancreáticas/enzimologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , beta Catenina/metabolismo , Quinases Ativadas por p21/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos Nus , Células-Tronco Neoplásicas/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Fosforilação , Serina , Transdução de Sinais , Esferoides Celulares , Carga Tumoral , beta Catenina/genética , Quinases Ativadas por p21/genéticaRESUMO
Although the role of insulin-like growth factor-I receptor (IGF-IR) in promoting colorectal liver metastasis is known, the mechanism by which IGF-IR is upregulated in colorectal cancer (CRC) is not defined. In this study, we obtained evidence that mutant KRAS transcriptionally activates IGF-IR gene expression through Y-box-binding protein (YB)-1 upregulation via a novel MEK-Sp1-DNMT1-miR-137 pathway in CRC cells. The mechanistic link between the tumor suppressive miR-137 and the translational regulation of YB-1 is intriguing because epigenetic silencing of miR-137 represents an early event in colorectal carcinogenesis due to promoter hypermethylation. This proposed signaling axis was further verified by the immunohistochemical evaluations of liver metastases from a cohort of 46 KRAS mutant CRC patients, which showed a significant correlation in the expression levels among Sp1, miR-137, YB-1, and IGF-1R. Moreover, suppression of the expression of YB-1 and IGF-IR via genetic knockdown or the pharmacological inhibition of MEK hampers KRAS-driven colorectal liver metastasis in our animal model studies. From a translational perspective, the identification of this KRAS-driven pathway might provide a mechanistic rationale for the use of a MEK inhibitor as an adjuvant, in combination with standard of care, to prevent the recurrence of colorectal liver metastasis in KRAS mutant CRC patients after receiving liver resection, which warrants further investigation.
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Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/secundário , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética , Animais , Apoptose , Biomarcadores Tumorais/genética , Movimento Celular , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/genética , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Feminino , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , MAP Quinase Quinase 1/genética , MAP Quinase Quinase 1/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , MicroRNAs/metabolismo , Fator de Transcrição Sp1/genética , Fator de Transcrição Sp1/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína 1 de Ligação a Y-Box/genética , Proteína 1 de Ligação a Y-Box/metabolismoRESUMO
Aristolochic acid (AA) is a common cause of Chinese herb nephropathy. The mechanisms involved in the pathogenesis of AA nephropathy (AAN) are intricate. One well-documented effect of AA in the kidney is its pro-fibrotic activity. Nitric oxide (NO), a messenger gas generated from l-arginine, is the product of nitric oxide synthase (NOS). NO is involved in renal hemodynamics and exerts cytoprotective effects against renal injury. In the present study, the role of NO in AAN was investigated in MES-13 cells, a glomerular mesangial cell line. NO endogenously generated by the induction of inducible nitric oxide synthase (iNOS) with lipopolysaccharide (LPS)/interferon-γ (IFN-γ) significantly downregulated connective tissue growth factor (CTGF) protein expression in MES-13 cells. AA significantly suppressed LPS/IFN-γ-induced NO production and reversed CTGF expression that was downregulated by LPS/IFN-γ. AA decreased iNOS gene and protein expressions in a concentration-dependent manner. AA caused declines in LPS/IFN-γ-induced signal transducer and activator of transcription-1α (STAT-1α) phosphorylation and interferon response factor-1 (IRF-1) mRNA expression. Furthermore, AA attenuated IκB phosphorylation and reduced NF-κB translocation to the nuclear fraction. Taken together, our data indicate that AA reversed the CTGF expression inhibited by LPS/IFN-γ treatment via suppression of NO and iNOS expressions in MES-13 cells through inhibition of the JAK/STAT-1α and NF-κB signaling pathways. NO potentially exerts antifibrotic activity by down regulation of CTGF in MES-13 cells and inhibition of the iNOS gene by AA might partially account for the fibrotic effects of AA in nephropathy.
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Ácidos Aristolóquicos/farmacologia , Regulação para Baixo/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Carcinógenos/farmacologia , Linhagem Celular , Fator de Crescimento do Tecido Conjuntivo/genética , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Relação Dose-Resposta a Droga , Mesângio Glomerular/citologia , Mesângio Glomerular/efeitos dos fármacos , Humanos , Fator Regulador 1 de Interferon/metabolismo , Interferon gama/farmacologia , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismoRESUMO
Prostate cancer is the most prevalent type of cancer in the United States. The most common site of prostate cancer metastasis is bone. CXCL12 is preferentially expressed in bone and is targeted by prostate cancer cells, which over-express the receptor for CXCL12, CXCR4. In response to CXCL12 stimulation, Rac1, a GTPase, along with its effectors, regulates actin polymerization to form lamellipodia, which is a critical event for cell migration. Cortactin, an actin-binding protein, is recruited to the lamellipodia and is phosphorylated at tyrosine residues. The phosphorylated cortactin is also involved in cell migration. The inhibition of Rac1 activity using a dominant negative Rac1 impairs lamellipodial protrusion as well as cortactin translocation and cortactin phosphorylation. Denbinobin, a substance extracted from Dendrobium nobile, has anticancer effects in many cancer cell lines. Whether denbinobin can inhibit prostate cancer cell migration is not clear. Here, we report that denbinobin inhibited Rac1 activity. The inhibition of Rac1 activity prevented lamellipodial formation. Cortactin phosphorylation and translocation to the lamellipodia were also impaired, and PC3 cells were unable to migrate. These results indicate that denbinobin prevents CXCL12-induced PC3 cell migration by inhibiting Rac1 activity.
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Antraquinonas/farmacologia , Antineoplásicos Fitogênicos , Movimento Celular/efeitos dos fármacos , Dendrobium/química , Fenantrenos/farmacologia , Neoplasias da Próstata/patologia , Proteínas rac1 de Ligação ao GTP/antagonistas & inibidores , Actinas/metabolismo , Antraquinonas/uso terapêutico , Quimiocina CXCL12/fisiologia , Cortactina/metabolismo , Humanos , Masculino , Fenantrenos/uso terapêutico , Fosforilação , Polimerização/efeitos dos fármacos , Neoplasias da Próstata/metabolismo , Pseudópodes/metabolismo , Células Tumorais Cultivadas , Proteínas rac1 de Ligação ao GTP/fisiologiaRESUMO
Quercetin, rich in fruits and vegetables, has been used as a nutritional supplement because of its anti-inflammatory and antioxidative properties. Its positive effects on anti-hepatic fibrosis have also been suggested. However the anti-hepatofibrotic mechanisms upon which quercetin acts have yet to be well characterized. In the present study, we investigated the anti-proliferative effect of quercetin on activated hepatic stellate cells (aHSCs), the central role of hepatofibrosis, and evaluated the proteins involved in growth inhibition by a 2D gel electrophoretic analysis. Activated HSCs were isolated from Sprague Dawley rats and were spontaneously activated in vitro. Quercetin restrained the proliferation of aHSCs rather than quiescent HSCs and heptotcytes by inducing a G(1) arrest as examined by cell cycle analysis and evidenced by increased levels of p53, p21(CIP1/WAF1), as well as p27(KIP1), and decreased abundance of cyclins (D(1), D(2), A, E). An apoptosis through extrinsic pathway as demonstrated by elevated expression of Fas/Fas ligand (FasL), annexin V labeling, chromatin condensation, sub-G(1) fraction (7.39%), caspase-3 activity, was also observed. The 2D electrophoresis analysis revealed that quercetin negatively regulated protein molecules associated with metabolism (α-enolase, phosphoglycerate kinase), survival, cytokinesis (tubulin), and protein folding (protein disulfide isomerase A3) leading to cell growth retardation. Furthermore, quercetin might restrain HSC activation through reducing the levels of inflammatory cytokines (CXCL10, Midkine). Taken together, quercetin exerted diverse mechanisms to inhibit the growth of aHSCs. Proper consumption of quercetin could be beneficial to control the progression of heptofibrosis.