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This paper aims to address the issue of environmental pollution resulting from marine oil spills by evaluating the oil adsorption performance of commonly used fence materials. Conventional oil adsorption materials exhibit limited rates and capacities for oil adsorption. Existing methods have proven insufficient in meeting the requirements for efficient and rapid oil-water separation. A new oil-absorbing barrier was developed by utilizing high oil adsorption resin as the primary material and hydroxypropyl methyl cellulose (HPMC) as the binder, leveraging the exceptional oil adsorption and hydrophobic properties of P(BMA-SMA-St)/MIL-101(Fe) resin. The oil-absorbing fence was characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The oil adsorption rates of carbon tetrachloride, toluene, diesel and gasoline by the oil adsorption fence with 25 g/L resin content were 101.26 g/m2, 68.12 g/m2, 35.19 g/m2, and 46.69 g/m2, respectively. After 120 h of UV irradiation, the coating's oil absorption capacity remained nearly unchanged, and it demonstrated outstanding mechanical, chemical, and wear resistance. As a result, the oil adsorption fence possesses the capability to rapidly absorb oil from the water's surface during the process of containing oil pollution, leading to positive social and economic impacts.
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Based on first-principles calculations in the density functional theory, we systematically investigated the possible interface structure, magnetism, and electronic properties of the all-Heusler alloy Co2MnGe/CoTiMnGe(100) heterojunction. The calculation indicated that the Co2MnGe Heusler alloy is a half-metal with a magnetic moment of 4.97 µB. CoTiMnGe is a narrow-band gap semiconductor and may act as an ultra-sensitive photocatalyst. We cannot find an "ideal" spin-polarization of 100% in CoCo termination and MnGe termination. Due to the interface interaction, the direct magnetic hybridization or indirect RKKY exchange will be weakened, leading to an increase in the atomic magnetic moment of the interfacial layer. For eight possible heterojunction structures, the half-metallic gaps in the Co2MnGe bulk have been destroyed by the inevitable interface states. The spin-polarization value of 94.31% in the CoCo-TiGe-B heterojunction revealed that it is the most stable structure. It is feasible to search for high-performance magnetic tunnel junction by artificially constructing suitable all-Heusler alloy heterojunctions.
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In this study, a multi-functional layer was developed based on the commercially available cellulose triacetate (CTA) forward osmosis (FO) membrane to improve its antifouling property. Tannic acid/ferric ion (TA/Fe3+) complexes were firstly coated as a precursor layer on the membrane surface via self-assembly. Afterwards, the tannic acid/diethylenetriamine (TA/DETA) hydrophilic functional layer was further coated, following Ag/polyvinylpyrrolidone (PVP) anti-bacterial layer was formed in situ through the reducibility of TA to obtain TA/Fe3+-TA/DETA-Ag/PVP-modified membrane. The optimized precursor layer was acquired by adjusting the buffer solution pH to 8, TA/Fe3+ ratio to 4 and the number of self-assembled layers to 5. The permeability testing results illustrated that the functional layer had an insignificant effect on the membrane transport parameters. The TA/Fe3+-TA/DETA-Ag/PVP-modified membrane simultaneously exhibited excellent physical and chemical stability. The coated membrane also demonstrated enhanced anti-bacterial properties, achieving 98.63 and 97.30% inhibition against Staphylococcus aureus and Escherichia coli, respectively. Furthermore, the dynamic fouling experiment showed a 12% higher water flux decrease for the TA/Fe3+-TA/DETA-Ag/PVP CTA membrane compared to the nascent CTA membrane, which proved its excellent antifouling performance. This work provides a feasible strategy to heighten the antifouling property of the CTA FO membrane.
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Incrustação Biológica , Membranas Artificiais , Osmose , Staphylococcus aureus , Incrustação Biológica/prevenção & controle , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Taninos/química , Fenóis/química , Antibacterianos/farmacologia , Antibacterianos/química , Purificação da Água/métodosRESUMO
The success of arsenic in acute promyelocytic leukemia (APL) treatment is hardly transferred to non-APL cancers, mainly due to the low selectivity and weak binding affinity of traditional arsenicals to oncoproteins critical for cancer survival. We present herein the reinvention of aliphatic trivalent arsenicals (As) as reversible covalent warheads of As-based targeting inhibitors toward Bruton's tyrosine kinase (BTK). The effects of As warheads' valency, thiol protection, methylation, spacer length, and size on inhibitors' activity were studied. We found that, in contrast to the bulky and rigid aromatic As warhead, the flexible aliphatic As warheads were well compatible with the well-optimized guiding group to achieve nanomolar inhibition against BTK. The optimized As inhibitors effectively blocked the BTK-mediated oncogenic signaling pathway, leading to elevated antiproliferative activities toward lymphoma cells and xenograft tumor. Our study provides a promising strategy enabling rational design of new aliphatic arsenic-based reversible covalent inhibitors toward non-APL cancer treatment.
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Arsênio , Arsenicais , Leucemia Promielocítica Aguda , Humanos , Leucemia Promielocítica Aguda/tratamento farmacológico , Arsenicais/farmacologia , Arsenicais/uso terapêutico , Arsênio/farmacologia , Tirosina Quinase da Agamaglobulinemia , Transdução de Sinais , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêuticoRESUMO
Based on the excellent adsorption properties of carbon materials, a new magnetic nanodemulsifier was prepared in this study. First, carbon nanotubes were oxidized using a solvothermal method. Then, Fe3O4 was combined with oxidized carbon nanotubes using a one-pot method, and then grafted onto fluorine-containing polyether to prepare a magnetic composite demulsifier (Fe3O4@C-F) with good demulsification properties. The surface morphology of the composite demulsifier was analyzed using scanning electron microscopy (SEM). The structure of the composite demulsifier was characterized using Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectrometry (XPS). The stability of the composite demulsifier was characterized using thermogravimetric analysis (TGA). Results showed that the oxidized carbon nanotubes and fluorinated polyether were successfully attached to Fe3O4. The experimental objective was to obtain a self-made crude oil emulsion. The demulsification test and recovery performance test were then performed, and the main factors affecting the demulsification performance of the demulsifier were investigated. Results showed that when the dosage was 800 mg L-1, the temperature was 65 °C, the demulsification time was 90 min, and the pH value was 6. The demulsification effect of the Fe3O4@C-F magnetic composite demulsifier was the best, whereby the demulsification rate could reach 91.68%, and the oil-water interface was clear. Fe3O4@C-F had a magnetic response and could be recycled from the two-phase system six times under the action of an external magnetic field. Fe3O4@C-F is an efficient and environmentally friendly demulsifier that has important application value for enriching demulsification technology systems.
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Over the past decade, colorectal cancer has reported a higher incidence in younger adults and a lower mortality rate. Recently, the influence of the intestinal flora in the initiation, progression, and treatment of colorectal cancer has been extensively studied, as well as their positive therapeutic impact on inflammation and the cancer microenvironment. Historically, traditional Chinese medicine (TCM) has been widely used in the treatment of colorectal cancer via promoted cancer cell apoptosis, inhibited cancer metastasis, and reduced drug resistance and side effects. The present research is more on the effect of either herbal medicine or intestinal flora on colorectal cancer. The interactions between TCM and intestinal flora are bidirectional and the combined impacts of TCM and gut microbiota in the treatment of colon cancer should not be neglected. Therefore, this review discusses the role of intestinal bacteria in the progression and treatment of colorectal cancer by inhibiting carcinogenesis, participating in therapy, and assisting in healing. Then the complex anticolon cancer effects of different kinds of TCM monomers, TCM drug pairs, and traditional Chinese prescriptions embodied in apoptosis, metastasis, immune suppression, and drug resistance are summarized separately. In addition, the interaction between TCM and intestinal flora and the combined effect on cancer treatment were analyzed. This review provides a mechanistic reference for the application of TCM and intestinal flora in the clinical treatment of colorectal cancer and paves the way for the combined development and application of microbiome and TCM.
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Neoplasias Colorretais , Medicamentos de Ervas Chinesas , Microbioma Gastrointestinal , Plantas Medicinais , Adulto , Humanos , Medicina Tradicional Chinesa , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Microambiente TumoralRESUMO
The metal organic frameworks (MOFs) are considered as the effective adsorbents for phosphate removal, while their ultrafine powders limit their practical application. In this study, we fabricate two chitosan (CS) gel beads added with different cerium-based MOFs and coated with PDA for phosphate adsorption. The MOFs doped in beads are CM1 and CM2, in which the Ce(III)/Ce(IV) ratio is 0.36 and 1.46, indicating CM2 is Ce(III) dominated and more suitable for phosphate removal. However, during the process of preparing gel beads, the mixture of chitosan and CM1/CM2 are added drop-by-drop to NaOH solution, leading to the decrease of Ce(III) contents in both of the two beads on account of oxidization. On this basis, in order to improve the phosphate uptake performance and enhance the mechanical strength, polydopamine (PDA) is applied to be coated on the outside. The adsorption capacities of CS-CM1 and CS-CM2 are no more than 20 mg/g higher than that of pure CS, which is also quite equal with the phosphate uptake of CS@PDA (63 mg/g). Due to the reduction of PDA, the content of Ce(III) increasing evidently in the two adsorbents. The maximum phosphate adsorption capacities are 146.8 mg/g and 114.8 mg/g for CS-CM1@PDA and CS-CM2@PDA, respectively. CS-CM2@PDA exhibits the largest treatment volume of â¼1166 BV in the fix-bed column study, much higher than that of CS-CM1@PDA (976 BV). The main reason is that Ce(III) could form binding with phosphate through ligand exchange and precipitation. Those inner-sphere interactions are much stronger than the electrostatic attraction between Ce(IV) and phosphate. Thus, due to this strong affinity, CS-CM2@PDA possessing a higher content of Ce(III) can capture phosphate more easier at low concentration. In summary, owing to reduction of PDA, the Cerium-based MOFs are successfully introduced in CS to realize excellent phosphate removal and exhibit a great prospect in application.
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Cério , Quitosana , Estruturas Metalorgânicas , Poluentes Químicos da Água , Fosfatos/química , Cério/química , Quitosana/química , Adsorção , Poluentes Químicos da Água/química , CinéticaRESUMO
In the past, the possibilistic C-means clustering algorithm (PCM) has proven its superiority on various medical datasets by overcoming the unstable clustering effect caused by both the hard division of traditional hard clustering models and the susceptibility of fuzzy C-means clustering algorithm (FCM) to noise. However, with the deep integration and development of the Internet of Things (IoT) as well as big data with the medical field, the width and height of medical datasets are growing bigger and bigger. In the face of high-dimensional and giant complex datasets, it is challenging for the PCM algorithm based on machine learning to extract valuable features from thousands of dimensions, which increases the computational complexity and useless time consumption and makes it difficult to avoid the quality problem of clustering. To this end, this paper proposes a deep possibilistic C-mean clustering algorithm (DPCM) that combines the traditional PCM algorithm with a special deep network called autoencoder. Taking advantage of the fact that the autoencoder can minimize the reconstruction loss and the PCM uses soft affiliation to facilitate gradient descent, DPCM allows deep neural networks and PCM's clustering centers to be optimized at the same time, so that it effectively improves the clustering efficiency and accuracy. Experiments on medical datasets with various dimensions demonstrate that this method has a better effect than traditional clustering methods, besides being able to overcome the interference of noise better.
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Algoritmos , Lógica Fuzzy , Análise por Conglomerados , Humanos , Aprendizado de Máquina , Redes Neurais de ComputaçãoRESUMO
The oxidation products and metabolic pathways of five Citrus flavonoids were studied by online electrochemical/quadrupole time-of-flight mass spectrometry (EC/Q-TOF/MS). The simulated oxidation metabolism of target compounds in phase I and phase â ¡ was carried out at boron-doped diamond (BDD) working electrode. The results obtained by EC-MS were compared with the conventional metabolism of rats and humans reported in previous literatures. In addition, the method of incubating the target compounds with rat liver microsomes in vitro was established, the target compounds and their metabolites were analyzed by high performance liquid chromatography coupled mass spectrometry. The structures of the metabolites were determined by accurate mass measurements and previous in vivo metabolite results. The results showed that the electrochemical oxidation metabolites were consistent with the results of in vitro incubation of liver microsomes, and also with the results reported in other literatures. As a consequence, EC/Q-TOF/MS is a promising and effective tool for studying metabolic transformation of different complex food components.
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Citrus , Flavonoides , Animais , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Microssomos Hepáticos , RatosRESUMO
In this study, a supercritical fluid chromatography (SFC) method based on ion pair reagents was used to separate alkaloids. The chromatographic parameters, including the stationary phase, additive type, additive concentration, outlet pressure, temperature and flow rate, were optimized. Baseline separation was completed in 20 min on an Agilent Pursuit 5 PFP column (4.6 × 150 mm) using carbon dioxide as the mobile phase and 7.5 mM sodium 1-pentanesulfonate as an additive with gradient elution at 140 bar, 60 °C, and a flow rate of 1.5 mL/min. The retention rate and resolution of the analytes were satisfactory. The limits of detection were 27.04-298.03 ng/mL, and the limits of quantification were 90.15-993.42 ng/mL. The recoveries of low and high concentrations were 77.46-111.86% and 83.84-111.00%, respectively. This ion pair additive greatly improved the separation efficiency of alkaloids. Consequently, this SFC method was successfully applied to the separation of alkaloids from Rhizoma corydalis.
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Alcaloides , Cromatografia com Fluido Supercrítico , Dióxido de Carbono , TemperaturaRESUMO
A boron nitride nanosheet (BNNS)-assisted matrix solid-phase dispersion method was established to microextract alkaloids from medicinal plants. The target compounds were identified by high-performance liquid chromatography coupled with ultraviolet detection and ion mobility quadrupole time-of-flight mass spectrometry. During the experimental process, several important parameters, including the type of dispersant, the amount of dispersant, the grinding time, and the type of elution solvent, were optimized. Finally, the BNNSs were chosen as the best dispersant, and their microcosmic morphologies were identified by scanning electron microscopy and transmission electron microscopy. Because of the special property of BNNSs, the cost of this experiment was greatly reduced, especially in elution volume, sample amount (50 mg), and extraction time (2 min). Under the best conditions, 50 mg of sample powder was dispersed with 50 mg of BNNSs, the grinding time was 120 s, the mixed powder was eluted with 200 µL of methanol, and good linearity (r2 > 0.9993) and satisfactory recoveries (80-100%) were obtained. The inter- and intraday precisions were acceptable, with RSDs lower than 2.01 and 4.84%, respectively. The limits of detection ranged from 2.54 to 15.00 ng/mL, and the limits of quantitation were 8.47 to 50.00 ng/mL. The proposed method was successfully applied for the determination of liensinine, isoliensinine, and neferine in lotus plumule.
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Alcaloides , Lotus , Compostos de Boro , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Pós , Extração em Fase Sólida/métodosRESUMO
In this study, mangosteen peel based activated carbon was prepared and first applied as adsorbent in matrix solid-phase dispersion (MSPD) for simultaneously extraction of flavonoids from Dendrobium huoshanense prior to their separation and determination by ultra-high performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UHPLC-Q-TOF/MS). The MSPD-UHPLC-Q-TOF/MS method was validated exhaustively. Good linearities (r2 ≥ 0.9929) were obtained for all target analytes. The limits of detection was in the range of 0.00387-0.159 µg/g. Satisfactory recoveries of six target compounds were between 80.02 and 99.49% and 85.32-99.86% for the low and high spiked level, respectively. Furthermore, relative to other common sorbent, the prepared mangosteen peel based activated carbon was less expensive and more environmentally-friendly. Consequently, the proposed method was a simple, efficient, low-cost, eco-friendly, time-saving and sensitive approach that could be successfully applied to the extraction and determination of flavonoids compounds in complex matrix.
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Alimento Funcional , Extração em Fase Sólida , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Espectrometria de Massas em TandemRESUMO
Non-invasive tracking for monitoring the selective delivery and transplantation of biotargeted agents in vivo has been employed as one of the most effective tools in the field of nanomedicine. Different nanoprobes have been developed and applied to bioimaging tissues and the treatment of diseases ranging from inflammatory and cardiovascular diseases to cancer. Herein, we will review the recent advances in the development of optics-responsive nanomaterials, including organic and inorganic nanoparticles, for multimodal bioimaging and targeted therapy. The main focus is placed on nanoprobe fabrication, mechanistic illustrations, and diagnostic, or therapeutical applications. These nanomedicine strategies have promoted a better understanding of the biological events underlying diverse disease etiologies, thereby facilitating diagnosis, illness evaluation, therapeutic effect, and drug discovery.
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Intelligent reversible crosslinked micelles that have a good balance of structure stability in normal tissue and controlled drug release responded to the tumor microenvironment are highly promising novel drug delivery systems. However, to date, there have been very few reports about mesoscale simulations of drug-loaded polymeric reversible crosslinked micelles. Here, dissipative particle dynamics (DPD) simulation, the nearest-neighbor bonding principle, and the nearest media-bead bond breaking principle were used to investigate the influence of physiological environment along with low tumor pH and reduction microenvironment on the stability and doxorubicin (DOX) distribution of the star polymer [PCL-b-P(HEMA-Se-SeË)-b-PPEGMA]6 diselenide crosslinked micelles with different diselenide crosslinking levels (CLs). The self-assembly process results obtained by DPD simulations reveal the formation of three-layer spherical micelles with the loaded DOX mainly distributed at the interfacial regions of the inner PCL core and middle HEMA layer. The structural stability and DOX loading capacity of the micelles can be improved by appropriately increasing the CL based on the nearest-neighbor bonding principle due to the effect of the pressure exerted by the crosslink that squeezes the loaded drugs from the intermediate and interfacial layers into the micelle core. Furthermore, the effect of breaking of the diselenide bond on the drug release properties was investigated through the use of the nearest media-bead bond breaking principle. A low CL gives rise to intense drug release, increasing the toxic side effects on the system. With the increase in the CL, the micelles show the transformation from local crosslinking to compact crosslinking, leading to slower drug release. Therefore, this work can provide some guidance on the mesoscale for the structural design and controlled construction of reversible crosslinked micelles for smart drug delivery systems.
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Antibióticos Antineoplásicos/química , Doxorrubicina/química , Portadores de Fármacos , Modelos Químicos , Compostos de Selênio/química , Simulação por Computador , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Metacrilatos/química , Micelas , Ácidos Polimetacrílicos/químicaRESUMO
Bisphenol analogues including bisphenol A and its derivatives are ubiquitous environmental contaminants and have been linked to adverse neurodevelopment effects on animals and humans. Most toxicological research focused on estrogen receptor mediated pathways and did not comprehensively clarify the observed toxicity. O-GlcNAcase (OGA), the highest level in brain, plays a critical role in controlling neuronal functions at multi-levels from molecule to animal behaviors. In this work, we intend to investigate the underlying molecular mechanisms for the neurotoxicity of bisphenol analogues by identifying their cellular targets and the resultant effects. The inhibitory actions of seven bisphenol analogues on the OGA activity at molecular level were investigated by our developed electrochemical biosensor. We found that their potency varied with substituent groups, in which tetrabromo bisphenol A (TBBPA) was the strongest. The seven bisphenol analogues (0-100 µM exposure) significantly inhibited OGA activity and up-regulated protein O-GlcNAcylation level in PC12 cells. Inhibition of OGA by bisphenol analogues further induced intracellular calcium, ROS, inflammation, repressed proliferation, interfered with cell cycle, induced apoptosis. And especially, 10 µM tetrabromo bisphenol A (TBBPA) exposure could impair the growth and development of neurite in human neural stem cells (hNSCs). Molecular docking for OGA/bisphenol analogue complexes revealed the hydrophobicity-dominated inhibition potency. OGA, as a new cellular target of bisphenol analogues, would illuminate the molecular mechanism of bisphenol analogues neurotoxicity.
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Compostos Benzidrílicos/toxicidade , Poluentes Ambientais/toxicidade , Células-Tronco Neurais/efeitos dos fármacos , Síndromes Neurotóxicas/enzimologia , Fenóis/toxicidade , beta-N-Acetil-Hexosaminidases/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Compostos Benzidrílicos/química , Cálcio/metabolismo , Proliferação de Células/efeitos dos fármacos , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Poluentes Ambientais/química , Humanos , Simulação de Acoplamento Molecular , Células-Tronco Neurais/enzimologia , Células-Tronco Neurais/imunologia , Crescimento Neuronal/efeitos dos fármacos , Síndromes Neurotóxicas/etiologia , Síndromes Neurotóxicas/imunologia , Células PC12 , Fenóis/química , Ratos , Espécies Reativas de Oxigênio/metabolismoRESUMO
Organophosphate flame retardants (OPFRs), as alternatives of brominated flame retardants, can cause neurodevelopmental effects similar to organophosphate pesticides. However, the molecular mechanisms underlying the toxicity remain elusive. O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT) regulates numerous neural processes through the O-GlcNAcylation modification of nuclear and cytoplasmic proteins. In this study, we aimed to investigate the molecular mechanisms accounting for the developmental neurotoxicity of OPFRs by identifying potential targets of OPFRs and the attendant effects. Twelve OPFRs were evaluated for inhibition of OGT activity using an electrochemical biosensor. Their potency differed with substituent groups. The alkyl group substituted OPFRs had no inhibitory effect. Instead, the six OPFRs substituted with aromatic or chlorinated alkyl groups inhibited OGT activity significantly, with tri-m-cresyl phosphate (TCrP) being the strongest. The six OPFRs (0-100⯵M exposure) also inhibited OGT activity in PC12 cells and decreased protein O-GlcNAcylation level. Inhibition of OGT by OPFRs might be involved in the subsequent toxic effects, including intracellular reactive oxygen species (ROS), calcium level, as well as cell proliferation and autophagy. Molecular docking of the OGT/OPFR complexes provided rationales for the difference in their structure-dependent inhibition potency. Our findings may provide a new biological target of OPFRs in their neurotoxicological actions, which might be a major molecular mechanism of OPFRs developmental neurotoxicity.
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Retardadores de Chama/toxicidade , N-Acetilglucosaminiltransferases/metabolismo , Aloxano/farmacologia , Animais , Autofagia/efeitos dos fármacos , Cálcio/metabolismo , Proliferação de Células/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Modelos Moleculares , Simulação de Acoplamento Molecular , Estrutura Molecular , N-Acetilglucosaminiltransferases/antagonistas & inibidores , N-Acetilglucosaminiltransferases/genética , Células PC12 , Conformação Proteica , Ratos , Espécies Reativas de OxigênioRESUMO
O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT) plays a critical role in modulating protein function in many cellular processes and human diseases such as Alzheimer's disease and type II diabetes, and has emerged as a promising new target. Specific inhibitors of OGT could be valuable tools to probe the biological functions of O-GlcNAcylation, but a lack of robust nonradiometric assay strategies to detect glycosylation, has impeded efforts to identify such compounds. Here we have developed a novel label-free electrochemical biosensor for the detection of peptide O-GlcNAcylation using protease-protection strategy and electrocatalytic oxidation of tyrosine mediated by osmium bipyridine as a signal reporter. There is a large difference in the abilities of proteolysis of the glycosylated and the unglycosylated peptides by protease, thus providing a sensing mechanism for OGT activity. When the O-GlcNAcylation is achieved, the glycosylated peptides cannot be cleaved by proteinase K and result in a high current response on indium tin oxide (ITO) electrode. However, when the O-GlcNAcylation is successfully inhibited using a small molecule, the unglycosylated peptides can be cleaved easily and lead to low current signal. Peptide O-GlcNAcylation reaction was performed in the presence of a well-defined small-molecule OGT inhibitor. The results indicated that the biosensor could be used to screen the OGT inhibitors effectively. Our label-free electrochemical method is a promising candidate for protein glycosylation pathway research in screening small-molecule inhibitors of OGT.
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Técnicas Biossensoriais , Técnicas Eletroquímicas , Inibidores Enzimáticos/isolamento & purificação , N-Acetilglucosaminiltransferases/antagonistas & inibidores , Acetilglucosamina/química , Acetilglucosamina/metabolismo , Inibidores Enzimáticos/química , Glicosilação , Humanos , N-Acetilglucosaminiltransferases/químicaRESUMO
PURPOSE: p33(ING1b), as a candidate tumour suppressor gene, has been found to be expressed a proportion of oral squamous cell carcinomas (OSCCs), however, its clinicopathological significance is not studied yet. Our aim was to investigate association of p33(ING1b) expression with clinicopathological variables and particularly interesting new cysteine-histidine rich protein (PINCH) in OSCCs. METHODS: p33(ING1b) expression was immunohistochemically examined in 20 normal oral mucosa specimens and 49 OSCCs. RESULTS: Normal squamous cells showed only p33(ING1b )nuclear expression (no cytoplasmic expression), with a rate of 90% positive cases. While 24% of OSCCs appeared cytoplasmic expression (11 of them with weak nuclear staining) and the rest tumours (76%) were negative for p33(ING1b). Furthermore, the cases having lymph node metastasis showed a higher frequency of positive cytoplasmic expression than those without metastasis (P = 0.03). The p33(ING1b) cytoplasmic expression was positively related to PINCH expression (P = 0.04), the cases positive for both proteins had a high rate of the metastasis (P = 0.03). CONCLUSIONS: The transfer of p33(ING1b) protein from the nucleus to the cytoplasm may result in loss of normal cellular function of the protein, which might play a role in the tumourigenesis and metastasis of OSCCs.
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Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Mucosa Bucal/metabolismo , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Proteínas Nucleares/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Adulto , Idoso , Feminino , Humanos , Proteína 1 Inibidora do Crescimento , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To investigate the effect of periodontal infection on circulating C-reactive protein (CRP) in type 2 diabetes patients. METHODS: 32 diabetes patients with advanced periodontitis participated in this study. They were compared to a group of 32 diabetes patients without periodontal disease, who were mathed with regard to age (+/- 3 years), gender and body mass index (+/- 1 kg/m2). The concentration of CRP on circulation was measured by ELISA. RESULTS: Significant difference was found in the level of CRP and the percentage of subjects with elevated CRP levels > or = 3 mg/L on circulation between the two groups(P < 0.05). CONCLUSION: Periodontal infection results in higher circulating CRP in type 2 diabetes patients. This elevated inflammatory factor may exacerbate insulin resistance and increase the risk for great vessels complications of diabetes mellitus.