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1.
Small ; : e2402438, 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38644689

RESUMO

The simple and low-cost construction of a 3D network structure is an ideal way to prepare high-performance electromagnetic wave (EMW) absorption materials. Herein, a series of carbon skeleton/carbon nanotubes/Ni3ZnC0.7 composites (CS/CNTs/Ni3ZnC0.7) are successfully prepared by in situ growth of Ni3ZnC0.7 and CNTs on 3D melamine sponge carbon. With the increase of precursor, Ni3ZnC0.7 nanoparticles nucleate and catalyze the generation of CNTs on the surface of the carbon skeleton. The minimum reflection loss (RL) value of the S60min composite (loading time of 60 min) reaches -86.6 dB at 1.6 mm and effective absorption bandwidth (EAB, RL≤-10 dB) is up to 9.3 GHz (8.7-18 GHz). The 3D network sponge carbon with layered micro/nanostructure and hollow skeleton promotes multiple reflection and absorption mechanisms of incident EMW. The N-doping and defects can be equivalent to an electric dipole, providing dipole polarization to increase dielectric relaxation. The uniform Ni3ZnC0.7 nanoparticles and CNTs play a key role in dissipating electromagnetic energy, blocking heat transfer, and enhancing the mechanical properties of the skeleton. Fortunately, the composite displays a quite low thermal conductivity of 0.09075 W m·K-1 and good flexibility, which can provide insulation and quickly recover to its original state after being stressed.

2.
Sensors (Basel) ; 24(11)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38894412

RESUMO

Surface roughness is one of the main bases for measuring the surface quality of machined parts. A large amount of training data can effectively improve model prediction accuracy. However, obtaining a large and complete surface roughness sample dataset during the ultra-precision machining process is a challenging task. In this article, a novel virtual sample generation scheme (PSOVSGBLS) for surface roughness is designed to address the small sample problem in ultra-precision machining, which utilizes a particle swarm optimization algorithm combined with a broad learning system to generate virtual samples, enriching the diversity of samples by filling the information gaps between the original small samples. Finally, a set of ultra-precision micro-groove cutting experiments was carried out to verify the feasibility of the proposed virtual sample generation scheme, and the results show that the prediction error of the surface roughness prediction model was significantly reduced after adding virtual samples.

3.
Molecules ; 28(3)2023 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-36770784

RESUMO

In this work, the effects of InP/ZnS quantum dots modified with amino or carboxyl group on the characteristic parameters in phase behavior, elastic modulus, relaxation time of the DPPC/DPPG mixed monolayers are studied by the Langmuir technology at the temperature of 37, 40 and 45 °C. Additionally, the information on the morphology and height of monolayers are obtained by the Langmuir-Bloggett technique and atomic force microscope technique. The results suggest that the modification of the groups can reduce the compressibility of monolayers at a higher temperature, and the most significant effect is the role of the amino group. At a high temperature of 45 °C, the penetration ability of InP/ZnS-NH2 quantum dots in the LC phase of the mixed monolayer is stronger. At 37 °C and 40 °C, there is no clear difference between the penetration ability of InP/ZnS-NH2 quantum dots and InP/ZnS-COOH quantum dots. The InP/ZnS-NH2 quantum dots can prolong the recombination of monolayers at 45 °C and accelerate it at 37 °C and 40 °C either in the LE phase or in the LC phase. However, the InP/ZnS-COOH quantum dots can accelerate it in the LE phase at all temperatures involved but only prolong it at 45 °C in the LC phase. This work provides support for understanding the effects of InP/ZnS nanoparticles on the structure and properties of cell membranes, which is useful for understanding the behavior about the ingestion of nanoparticles by cells and the cause of toxicity.

4.
Immunopharmacol Immunotoxicol ; 44(6): 886-893, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35815670

RESUMO

BACKGROUND: The inhibitory effect of Tetrandrine (Tet) on rheumatoid arthritis (RA) is well established. However, its exact molecular mechanism remains unknown. METHODS: RT-qPCR coupled with western blotting was employed to analyze the expression of NEAT1, miR-17-5p, and STAT3 in RA tissues and/or RA-fibroblast-like synoviocytes (RA-FLS) treated with 3 µmol/L of Tet for 48 h. Cell Counting Kit-8 assay and flow cytometry were performed to assess RA-FLS proliferation and apoptosis. Luciferase reporter assays were used to validate the interactions between miR-17-5p and STAT3 or NEAT1. RESULTS: The expression of NEAT1 decreased in a time-dependent manner upon Tet treatment. Tet significantly inhibited RA-FLS proliferation and triggered apoptosis by downregulating NEAT1 expression. Additionally, NEAT1 directly targeted miR-17-5p to upregulate STAT3 expression. Tet-induced low NEAT1 expression impaired RA-FLS growth by targeting miR-17-5p and inhibiting STAT3. CONCLUSION: Tet exerts its inhibitory role in RA progression by regulating the NEAT1/miR-17-5p/STAT3 pathway.


Assuntos
Artrite Reumatoide , MicroRNAs , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/genética , MicroRNAs/genética , Fator de Transcrição STAT3/genética
5.
Entropy (Basel) ; 24(11)2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36359621

RESUMO

Coherent states, known as displaced vacuum states, play an important role in quantum information processing, quantum machine learning, and quantum optics. In this article, two ways to digitally prepare coherent states in quantum circuits are introduced. First, we construct the displacement operator by decomposing it into Pauli matrices via ladder operators, i.e., creation and annihilation operators. The high fidelity of the digitally generated coherent states is verified compared with the Poissonian distribution in Fock space. Secondly, by using Variational Quantum Algorithms, we choose different ansatzes to generate coherent states. The quantum resources-such as numbers of quantum gates, layers and iterations-are analyzed for quantum circuit learning. The simulation results show that quantum circuit learning can provide high fidelity on learning coherent states by choosing appropriate ansatzes.

6.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(4): 740-748, 2022 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-36008338

RESUMO

The design of wall filter in ultrasonic microvascular imaging directly affects the resolution of blood flow imaging. We compared the traditional polynomial regression wall filter algorithm and two algorithms based on singular value decomposition (SVD), Full-SVD algorithm and RS-RSVD algorithm (random sampling based on random singular value decomposition) through experiments with simulated data and human renal entity data imaging experiments. The experimental results showed that the filtering effect of the traditional polynomial regression wall filter algorithm was limited, however, Full-SVD algorithm and RS-RSVD algorithm could better extract the micro blood flow signal from the tissue or noise signal. When RS-RSVD algorithm was randomly divided into 16 blocks, the signal-to-noise ratio was the same as that of Full-SVD algorithm, reduces the contrast-to-noise ratio by 2.05 dB, and reduces the execution time by 90.41%. RS-RSVD algorithm can improve the operation efficiency and is more conducive to the real-time imaging of high frame rate ultrasound microvessels.


Assuntos
Algoritmos , Ultrassom , Humanos , Microvasos/diagnóstico por imagem , Razão Sinal-Ruído , Ultrassonografia/métodos
7.
Crit Care ; 25(1): 234, 2021 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-34217339

RESUMO

BACKGROUND: The coronavirus disease 2019 (COVID-19) has induced a worldwide epidemiological event with a high infectivity and mortality. However, the predicting biomarkers and their potential mechanism in the progression of COVID-19 are not well known. OBJECTIVE: The aim of this study is to identify the candidate predictors of COVID-19 and investigate their underlying mechanism. METHODS: The retrospective study was conducted to identify the potential laboratory indicators with prognostic values of COVID-19 disease. Then, the prognostic nomogram was constructed to predict the overall survival of COVID-19 patients. Additionally, the scRNA-seq data of BALF and PBMCs from COVID-19 patients were downloaded to investigate the underlying mechanism of the most important prognostic indicators in lungs and peripherals, respectively. RESULTS: In total, 304 hospitalized adult COVID-19 patients in Wuhan Jinyintan Hospital were included in the retrospective study. CEA was the only laboratory indicator with significant difference in the univariate (P < 0.001) and multivariate analysis (P = 0.020). The scRNA-seq data of BALF and PBMCs from COVID-19 patients were downloaded to investigate the underlying mechanism of CEA in lungs and peripherals, respectively. The results revealed the potential roles of CEA were significantly distributed in type II pneumocytes of BALF and developing neutrophils of PBMCs, participating in the progression of COVID-19 by regulating the cell-cell communication. CONCLUSION: This study identifies the prognostic roles of CEA in COVID-19 patients and implies the potential roles of CEACAM8-CEACAM6 in the progression of COVID-19 by regulating the cell-cell communication of developing neutrophils and type II pneumocyte.


Assuntos
COVID-19/metabolismo , Antígeno Carcinoembrionário/metabolismo , Pneumonia Viral/metabolismo , Adulto , Idoso , Biomarcadores/metabolismo , Líquido da Lavagem Broncoalveolar/química , COVID-19/mortalidade , Comunicação Celular , China/epidemiologia , Progressão da Doença , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Nomogramas , Pneumonia Viral/mortalidade , Pneumonia Viral/virologia , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , SARS-CoV-2 , Análise de Sobrevida
8.
Analyst ; 144(10): 3405-3413, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-30994646

RESUMO

A novel ultrasensitive photoelectrochemical sensor for benzoyl peroxide (BPO) was constructed under visible light irradiation. A novel nanostructured material made of molecularly imprinted polymer (MIP)-modified silver iodide nanoparticle-titanium dioxide nanotube arrays (AgINPs-TiO2 NTs) was designed as a photoactive electrode (denoted as MIP@AgINPs-TiO2 NTs). AgI-sensitized TiO2 nanotube arrays were prepared by a simple dissolution-precipitation-calcination process and then employed as a matrix to graft the MIP recognition element. Such a newly designed molecularly imprinted photoelectrochemical sensor exhibits high sensitivity and selectivity for the determination of BPO. The photoelectrochemical analysis is highly linear over the BPO concentration range from 1 × 10-12 mol L-1 to 5 × 10-10 mol L-1 with a detection limit of 2.53 × 10-13 mol L-1 (S/N = 3, n = 11). The sensor designed based on a low cost and highly sensitive assay was successfully applied in the determination of BPO in spiked samples.

9.
Biol Res ; 52(1): 24, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30995936

RESUMO

BACKGROUND: To analyze the relative expression of PELI3 and its mechanistic involvement in the non-small cell lung cancer (NSCLC). METHODS: PELI3 expression in NSCLC tissue samples was determined by the immunohistochemistry. The transcripts abundance of PELI3 was measured with real-time PCR. The protein intensity was analyzed by western blot. The overall survival in respect to PELI3 or miR-365a-5p expression was plotted by the Kaplan-Meier's analysis. Cell growth was determined by colony formation assay. Cell viability was measured by MTT assay. The migration and invasion were evaluated by wound healing and transwell assay respectively. The regulatory effect of miR-365a-5p on PELI3 was interrogated with luciferase reporter assay. The direct binding between miR-365a-5p and PELI3 was analyzed by pulldown assay. RESULTS: PELI3 was aberrantly up-regulated in NSCLC both in vivo and in vitro. High level of PELI3 associated with poor prognosis. PELI3-deficiency significantly inhibited cell viability, colony formation, migration and invasion. We further identified that miR-365a-5p negatively regulated PELI3 in this disease. Ectopic expression of miR-365a-5p in both A549 and H1299 phenocopied PELI3-deficiency. Meanwhile, PELI3-silencing significantly abolished the pro-tumoral effect elicited by miR-365a-5p inhibition. CONCLUSION: Our results highlighted the importance of dysregulated miR-365a-5p-PELI3 signaling axis in NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Regulação para Baixo/fisiologia , Neoplasias Pulmonares/metabolismo , MicroRNAs/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Corantes , Modelos Animais de Doenças , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , MicroRNAs/uso terapêutico , Sais de Tetrazólio , Tiazóis , Ubiquitina-Proteína Ligases/farmacologia
10.
Mikrochim Acta ; 186(11): 688, 2019 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31595361

RESUMO

A molecularly imprinted polymer photoelectrochemical (MIP-PEC) sensor based on bismuth sulfide (Bi2S3) is described for the determination of the plasticizer dioctyl phthalate (DOP). Bi2S3 was used as the photoelectrical converter of the sensor, and visible light was utilized as the excitation source. The molecular imprinting film was prepared through the electropolymerization of monomers in the presence of DOP. Under optimal experimental conditions, the photoelectrochemical response was linearly proportional to the logarithm of the DOP concentration in the 0.5-70 pM DOP concentration range, and the detection limit was 0.1 pM. The method is highly stable and reproducible. It was applied to the determination of DOP in spiked water samples. Graphical abstract A novel molecularly imprinted photoelectrochemical sensor with high sensitivity and high selectivity based on Bi2S3 was developed for dioctyl phthalate detection. Bi2S3 was firstly used as a photoelectric converter in photoelectrochemical sensor to improve the sensitivity of the sensor. Combining photocurrent measurement with molecular imprinting technique makes the sensor highly selective.

11.
Mikrochim Acta ; 186(7): 446, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31197478

RESUMO

A method is described for colorimetric determination of glucose by using hemin-porous graphitic carbon nitride (g-C3N4) hybrid nanosheets as a peroxidase mimic. The porous g-C3N4 nanosheets were prepared by a combination of one-pot self-polymerization, pyrolysis and liquid-phase exfoliation. The hemin-porous g-C3N4 hybrid nanosheets were prepared via in-situ deposition. It is shown that the hybrid composite has improved dispersibility, stability, and peroxidase-mimicking activity in the 3,3',5,5'-tetramethylbenzidine (TMB)/H2O2 system. This is deemed to be the result of the synergistic effect of hemin and porous g-C3N4 nanosheets. Based on these advantages of the nanosheets, a simple, low-cost, sensitive and selective colorimetric method was established for the determination of glucose at pH values around 7. Best performed at a wavelength of 652 nm, the assay has a linear response in the 10.0 µM to 500 µM glucose concentration range (R2 = 0.9942) and a 1.94 µM limit of detection. This method was successfully applied to the determination of glucose in (spiked) human serum samples. In our perception, the hybrid is a robust peroxidase mimic for use in POx-based assays as needed in medical diagnosis and environmental analysis. Graphical abstract Schematic presentation of the process of hemin-porous g-C3N4 hybrid nanosheets catalyzing the oxidation of peroxidase chromogenic substrate tetramethylbenzidine (TMB) in the presence of H2O2. The material was applied in colorimetric and visual determination of H2O2 and glucose.


Assuntos
Glicemia/análise , Colorimetria/métodos , Grafite/química , Hemina/química , Nanoestruturas/química , Compostos de Nitrogênio/química , Benzidinas/química , Materiais Biomiméticos/síntese química , Materiais Biomiméticos/química , Corantes/química , Glucose Oxidase/química , Grafite/síntese química , Humanos , Peróxido de Hidrogênio/química , Limite de Detecção , Compostos de Nitrogênio/síntese química , Oxirredução , Peroxidase/química
12.
J Electrocardiol ; 51(2): 309-315, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29132927

RESUMO

OBJECTIVE: This study aimed to identify the pathogenic mutation in a Chinese family with unexplained sudden death (USD) or occasional syncope. MATERIALS AND METHODS: Whole exome sequencing and target capture sequencing were respectively conducted for two related patients. The genetic data was screened using the 1000 genomes project and SNP database (PubMed), and the identified mutations were assessed for predicted pathogenicity using the SIFT and Polyphen-2 algorithms. RESULTS: We identified a heterozygous mutation in the RYR2 gene at c.490C>T (p.P164S), highly conserved across all species, in three family members of USD, syncope and malignant ventricular tachycardias induced by treadmill exercise test, while another heterozygous de novo mutation in SCN5A at c.5576G>A p.R1859H was detected in one family member. Both variants were verified by Sanger sequencing. Importantly, RYR2 p.P164S is associated with the risk of sudden cardiac death, such as in catecholaminergic polymorphic ventricular tachycardia. CONCLUSIONS: A pathogenic mutation in RYR2 (p.P164S) is the likely cause of USD in a Chinese family associated with malignant ventricular arrhythmias. Whole exome and target capture sequencing can be useful for discovering the genetic causes of USD.


Assuntos
Morte Súbita Cardíaca , Sequenciamento do Exoma , Mutação/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Adolescente , Adulto , Idoso , Algoritmos , Povo Asiático , Criança , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Síncope/genética
13.
Molecules ; 21(3): 314, 2016 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-27005602

RESUMO

A vast number of structural modifications have been performed for khellactone derivatives (KDs) that have been widely concerned owing to their diverse biological properties, including anti-hypertension, anti-HIV, reversing P-glycoprotein (P-gp) mediated multidrug resistance, and anti-inflammation effects, to find the most active entity. However, extensive metabolism of KDs results in poor oral bioavailability, thus hindering the clinical trial performance of those components. The primary metabolic pathways have been revealed as hydrolysis, oxidation, acyl migration, and glucuronidation, while carboxylesterases and cytochrome P450 3A (CPY3A), as well as UDP-glucuronosyltransferases (UGTs) primarily mediate these metabolic pathways. Attention was mainly paid to the pharmacological features, therapeutic mechanisms and structure-activity relationships of KDs in previous reviews, whereas their pharmacokinetic and metabolic characteristics have seldom been discussed. In the present review, KDs' metabolism and their pharmacokinetic properties are summarized. In addition, the structure-metabolism relationships of KDs and the potential drug-drug interactions (DDIs) induced by KDs were also extensively discussed. The polarity, the acyl groups substituted at C-3' and C-4' positions, the configuration of C-3' and C-4', and the moieties substituted at C-3 and C-4 positions play the determinant roles for the metabolic profiles of KDs. Contributions from CYP3A4, UGT1A1, P-gp, and multidrug resistance-associated protein 2 have been disclosed to be primary for the potential DDIs. The review is expected to provide meaningful information and helpful guidelines for the further development of KDs.


Assuntos
Fármacos Anti-HIV/farmacocinética , Anti-Hipertensivos/farmacocinética , Disponibilidade Biológica , Cumarínicos/farmacocinética , Fármacos Anti-HIV/química , Anti-Hipertensivos/química , Cumarínicos/química , Cumarínicos/uso terapêutico , Interações Medicamentosas , Infecções por HIV/tratamento farmacológico , Humanos , Hipertensão/tratamento farmacológico , Redes e Vias Metabólicas/efeitos dos fármacos , Oxirredução , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Relação Estrutura-Atividade
14.
Dig Dis Sci ; 59(8): 1779-88, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24728967

RESUMO

BACKGROUND: Phospholipase D (PLD) has been proved to be involved in regulating function of fibroblasts and might play a role in mediating organic fibrosis. AIMS: To investigate the role and mechanism of PLD on dimethylnitrosamine (DMN)-induced rat liver fibrosis. METHODS: Fifty-five male Wistar rats were divided into normal control group, DMN model group, N-methylethanolamine (MEA) control group, and MEA-intervention group. We observed the effects of MEA, a PLD inhibitor on the development and progression of rat liver fibrosis by comparing the physical and biochemical indexes, tissue pathology, PLD activity, and typical markers and cytokines related to fibrosis in the four groups. RESULTS: Accompanied by the down-regulation of PLD1 expression, the MEA-intervention group had improved outcomes compared with the DMN model group in terms of spleen weight, spleen/weight index, serum and tissue biochemical indexes, tissue hydroxyproline, and tissue pathology. The MEA-intervention group had lower TIMP1, COL1A1, and higher MMPs expression level than the DMN model group. The activity of PLD and PLD1, α-SMA expression level in the MEA-intervention group was much lower than those in the DMN model group. There was no significant difference between the two groups in the expression level of TGF-ß1 and MCP1. Meanwhile, there were no significant differences between normal control group and MEA control group in the parameters stated above. CONCLUSION: Phospholipase D1 may play an important role in the development and progression of rat liver fibrosis. Inhibition of PLD may become a new strategy to prevent or alleviate liver fibrosis.


Assuntos
Cirrose Hepática/enzimologia , Fosfolipase D/metabolismo , Actinas/metabolismo , Animais , Dimetilnitrosamina , Progressão da Doença , Regulação para Baixo , Fígado/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/patologia , Masculino , Ratos , Ratos Wistar , Fator de Crescimento Transformador beta1/metabolismo
15.
Sci Data ; 11(1): 769, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38997427

RESUMO

Named entity recognition is a fundamental subtask for knowledge graph construction and question-answering in the agricultural diseases and pests field. Although several works have been done, the scarcity of the Chinese annotated dataset has restricted the development of agricultural diseases and pests named entity recognition(ADP-NER). To address the issues, a large-scale corpus for the Chinese ADP-NER task named AgCNER was first annotated. It mainly contains 13 categories, 206,992 entities, and 66,553 samples with 3,909,293 characters. Compared with other datasets, AgCNER maintains the best performance in terms of the number of categories, entities, samples, and characters. Moreover, this is the first publicly available corpus for the agricultural field. In addition, the agricultural language model AgBERT is also fine-tuned and released. Finally, the comprehensive experimental results showed that BiLSTM-CRF achieved F1-score of 93.58%, which would be further improved to 94.14% using BERT. The analysis from multiple aspects has verified the rationality of AgCNER and the effectiveness of AgBERT. The annotated corpus and fine-tuned language model are publicly available at https://doi.org/XXX and https://github.com/guojson/AgCNER.git .


Assuntos
Agricultura , China , População do Leste Asiático
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 322: 124817, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39029197

RESUMO

Surface plasmon driven photocatalytic reactions have great potential for information encryption as well as information security. In this paper, explored the detection concentrations of dye molecule Rhodamine6G (R6G) on three substrates, where complete original Raman spectra signals were still obtained at a concentration of 10-8 M. Utilized photosensitive molecules to investigate the photocatalytic characteristics of 4-nitrobenzenethiol (4-NBT) on three substrates. Excitation light at a wavelength of 633 nm enables local photocatalytic for information signals writing, while 785 nm wavelength excitation light combined with two-dimensional Mapping technology is used for information signal reading. Read information signals are often prone to reading errors due to their own lack of resolution or strong interference from back bottom signals, so error correction processing of information signals is essential. Through comparative exploration, it is found that the ratio method can obtain high-precision and high-resolution information signals, and the interference of the background signals were well suppressed. Leveraging the advantages of Raman fingerprint spectra at the micro/nanoscale, it solves the challenge of incomplete information signals presentation at smaller scales. Additionally, through error correction processing of the information signals, high precision and high-resolution information signals are obtained.

17.
Front Bioeng Biotechnol ; 12: 1346404, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38737539

RESUMO

Objective: Titanium implants are widely used in surgeries for their biocompatibility and mechanical properties. However, excessive titanium particle release can cause implant failure. This study explores Atomic Layer Deposition (ALD) to coat commercially pure titanium (Cp-Ti) with TiO2, aiming to improve its frictional and corrosion resistance while reducing particle release. By comparing TiO2 films with varying ALD cycle numbers, we assess surface properties, particle release, friction, and corrosion performance, providing insights into mitigating particle release from implants. Methods: Cp-Ti surfaces were prepared and coated with TiO2 films of 100, 300, and 500 ALD cycles. Surface characterization involved SEM, EDX, and XRD. Friction was tested using SEM, nanoindentation, and ICP-MS. Corrosion resistance was evaluated through immersion tests and electrochemical analysis. Cytotoxicity was assessed using BMSCs. Results: Surface characterization revealed smoother surfaces with increased ALD cycles, confirming successful TiO2 deposition. Friction testing showed reduced friction coefficients with higher ALD cycles, supported by nanoindentation results. Corrosion resistance improved with increasing ALD cycles, as evidenced by electrochemical tests and reduced titanium release. Cytotoxicity studies showed no significant cytotoxic effects. Conclusion: ALD-coated TiO2 films significantly enhance frictional and corrosion resistance of titanium implants while reducing particle release. The study underscores the importance of ALD cycle numbers in optimizing film performance, offering insights for designing implants with improved properties.

18.
Anal Chim Acta ; 1306: 342598, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38692791

RESUMO

BACKGROUND: Carbon-based nanozymes have recently received enormous concern, however, there is still a huge challenge for inexpensive and large-scale synthesis of magnetic carbon-based "Two-in-One" mimics with both peroxidase (POD)-like and laccase-like activities, especially their potential applications in multi-mode sensing of antibiotics and neurotransmitters in biofluids. Although some progresses have been made in this field, the feasibility of biomass-derived carbon materials with both POD-like and laccase-like activities by polyatomic doping strategy is still unclear. In addition, multi-mode sensing platform can provide a more reliable result because of the self-validation, self-correction and mutual agreement. Nevertheless, the use of magnetic carbon-based nanozyme sensors for the multi-mode detection of antibiotics and neurotransmitters have not been investigated. RESULTS: We herein report a shrimp shell-derived N, O-codoped porous carbon confined magnetic CuFe2O4 nanosphere with outstanding laccase-like and POD-like activities for triple-mode sensing of antibiotic d-penicillamine (D-PA) and chloramphenicol (CPL), as well as colorimetric detection of neurotransmitters in biofluids. The magnetic CuFe2O4/N, O-codoped porous carbon (MCNPC) armored mimetics was successfully fabricated using a combined in-situ coordination and high-temperature crystallization method. The synthesized MCNPC composite with superior POD-like activity can be used for colorimetric/temperature/smartphone-based triple-mode detection of D-PA and CPL in goat serum. Importantly, the MCNPC nanozyme can also be used for colorimetric analysis of dopamine and epinephrine in human urine. SIGNIFICANCE: This work not only offered a novel strategy to large-scale, cheap synthesize magnetic carbon-based "Two-in-One" armored mimetics, but also established the highly sensitive and selective platforms for triple-mode monitoring D-PA and CPL, as well as colorimetric analysis of neurotransmitters in biofluids without any tanglesome sample pretreatment.


Assuntos
Antibacterianos , Carbono , Cobre , Neurotransmissores , Carbono/química , Antibacterianos/análise , Antibacterianos/urina , Antibacterianos/sangue , Neurotransmissores/urina , Neurotransmissores/análise , Neurotransmissores/sangue , Porosidade , Cobre/química , Humanos , Nanosferas/química , Colorimetria/métodos , Compostos Férricos/química , Materiais Biomiméticos/química , Animais , Técnicas Biossensoriais/métodos , Cloranfenicol/análise , Cloranfenicol/urina , Limite de Detecção
19.
Food Chem ; 441: 138365, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38211476

RESUMO

In this work, shrimp shell-derived magnetic NiFe2O4/N, O co-doped porous carbon nanozyme with superior oxidase (OXD)-like activity was prepared and used for colorimetric/photothermal/smartphone dual-signal triple-mode detection of antioxidants in fruits and beverages. The magnetic NiFe2O4/N, O co-doped porous carbon (MNPC) material was triumphantly fabricated using a combined in-situ surface chelation and pyrolysis method. The resultant MNPC composite exhibits a superior OXD-like activity, which can effectively oxidize 3,3',5,5'-tetramethylbenzidine (TMB) for yielding colorimetric/temperature dual-signal (CTDS) in absence of H2O2. This CTDS output sensor was successfully used for the determination of ascorbic acid and tannic acid. The proposed CTDS sensor with good specificity and high sensitivity can satisfy different on-site analysis requirements. Interestingly, the MNPC as a sustainable filler was further used for improving packaging properties of polyvinyl alcohol film. In short, this work offers a large-scale and cheap method to fabricate magnetic carbon-based nanozyme for monitoring antioxidants and ameliorating packaging properties.


Assuntos
Óxido de Alumínio , Antioxidantes , Peróxido de Hidrogênio , Óxido de Magnésio , Polifenóis , Porosidade , Carbono , Colorimetria
20.
Int J Mol Med ; 51(2)2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36633140

RESUMO

Exercise is the main treatment for patients with metabolic­associated fatty liver disease (MAFLD); however, it may be difficult for some patients to adhere to or tolerate an exercise regime. Thus, finding a treatment alternative to exercise is of particular importance. The authors have previously demonstrated that the high expression of microRNA (miRNA/miR)­212 promotes lipogenesis in vitro. The present study aimed to explore the therapeutic potential, as well as the mechanisms of action of miR­212 in MAFLD. The expression of miR­212­3p, but not that of miR­212­5p, was found to be significantly elevated in MAFLD and to be decreased by exercise. Compared with exercise treatment, the inhibition of miR­212­3p expression in a mouse model fed a high­fat diet exerted beneficial effects on MAFLD similar to those of exercise. Conversely, the overexpression of miR­212­3p abolished the ameliorative effects of exercise on MAFLD. Fibroblast growth factor 21 (FGF21) and chromodomain helicase DNA binding protein 1 (CHD1) were identified as target genes of miR­212­3p in lipid metabolism using bioinformatics analysis. Mechanistically, the inhibition of miR­212­3p mimicked the effects of exercise on lipid metabolism by regulating FGF21, but not CHD1. The exercise­related transcription factor, early growth response 1 (EGR1), was identified upstream of miR­212­3p through promoter motif analysis. EGR1 overexpression inhibited miR­212­3p expression. The overexpression of miR­212­3p abolished the effects of exercise on lipid metabolism by exogenously attenuating the transcriptional repression of EGR1. Moreover, the overexpression of miR­212­3p abolished the regulatory effects of EGR1 on FGF21. On the whole, the present study demonstrates that miR­212­3p plays a key role in the effects of exercise on MAFLD. The findings presented herein suggest a potential therapeutic effect of targeting miR­212­3p in MAFLD.


Assuntos
Terapia Genética , Lipogênese , MicroRNAs , Hepatopatia Gordurosa não Alcoólica , Animais , Camundongos , Lipogênese/genética , Fígado/metabolismo , MicroRNAs/genética , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/terapia , Terapia Genética/métodos , Modelos Animais de Doenças , Exercício Físico , Condicionamento Físico Animal
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