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2.
Clin Oral Investig ; 28(7): 390, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38902486

RESUMO

OBJECTIVES: to understand the morphological characteristics of iliac crest and provide advice and assistance for jaw bone reconstruction with iliac bone flap by evaluating the thickness and curvature of iliac crest. MATERIALS AND METHODS: 100 patients who had taken Spiral CT of the Abdominal region before surgeries between 2020 and 2022 were included in this study. 3D reconstruction images of the iliac bones were created. 5 vertical planes perpendicular to the iliac crest were made every 2 cm along the centerline of the iliac crest (VP2 ~ VP10). On these vertical planes, 4 perpendicular lines were made every 1 cm along the long axis of the iliac crest (D1 ~ D4). The thicknesses at these sites, horizontal angle (HA) of iliac crest and the distance between inflection point and the central point of anterior superior iliac spine (DIA) were measured. RESULTS: The thickness of iliac bone decreased significantly from D1 ~ D4 on VP6 ~ VP10 and from VP2 ~ VP10 on D3 and D4 level (P<0.05). HA of iliac crests was 149.13 ± 6.92°, and DIA was 7.36 ± 1.01 cm. Iliac bone thickness, HA and DIA had very weak or weak correlation with patient's age, height and weight. CONCLUSIONS: The average thicknesses of iliac crest were decreased approximately from front to back, from top to bottom. The thickness and curvature of the iliac crest were difficult to predict by age, height and weight. CLINICAL RELEVANCE: Virtual surgical planning is recommended before jaw bone reconstruction surgery with iliac bone flap, and iliac crest process towards alveolar process might be a better choice.


Assuntos
Ílio , Imageamento Tridimensional , Humanos , Ílio/transplante , Ílio/diagnóstico por imagem , Ílio/cirurgia , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Imageamento Tridimensional/métodos , Tomografia Computadorizada Espiral , Idoso , Retalhos Cirúrgicos , Procedimentos de Cirurgia Plástica/métodos , Transplante Ósseo/métodos
3.
Int J Mol Sci ; 25(11)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38891866

RESUMO

Vibrio fluvialis is an emerging foodborne pathogenic bacterium that can cause severe cholera-like diarrhea and various extraintestinal infections, posing challenges to public health and food safety worldwide. The arginine deiminase (ADI) pathway plays an important role in bacterial environmental adaptation and pathogenicity. However, the biological functions and regulatory mechanisms of the pathway in V. fluvialis remain unclear. In this study, we demonstrate that L-arginine upregulates the expression of the ADI gene cluster and promotes the growth of V. fluvialis. The ADI gene cluster, which we proved to be comprised of two operons, arcD and arcACB, significantly enhances the survival of V. fluvialis in acidic environments both in vitro (in culture medium and in macrophage) and in vivo (in mice). The mRNA level and reporter gene fusion analyses revealed that ArgR, a transcriptional factor, is necessary for the activation of both arcD and arcACB transcriptions. Bioinformatic analysis predicted the existence of multiple potential ArgR binding sites at the arcD and arcACB promoter regions that were further confirmed by electrophoretic mobility shift assay, DNase I footprinting, or point mutation analyses. Together, our study provides insights into the important role of the ArgR-ADI pathway in the survival of V. fluvialis under acidic conditions and the detailed molecular mechanism. These findings will deepen our understanding of how environmental changes and gene expression interact to facilitate bacterial adaptations and virulence.


Assuntos
Proteínas de Bactérias , Regulação Bacteriana da Expressão Gênica , Hidrolases , Animais , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Camundongos , Hidrolases/metabolismo , Hidrolases/genética , Regiões Promotoras Genéticas , Óperon/genética , Proteínas Repressoras/metabolismo , Proteínas Repressoras/genética , Vibrio/genética , Vibrio/metabolismo , Vibrio/patogenicidade , Arginina/metabolismo , Família Multigênica , Virulência/genética , Viabilidade Microbiana
4.
Pharmaceuticals (Basel) ; 17(6)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38931366

RESUMO

Novel potassium-competitive acid blockers (P-CABs) have emerged as effective acid-suppressive drugs in recent years, replacing proton pump inhibitors (PPIs). We aim to compare the efficacy and safety of P-CABs versus PPIs in the treatment of peptic ulcers with or without Helicobacter pylori (H. pylori) infection. We searched in PubMed, Embase, WOS, Cochrane Library, ClinicalTrials.gov, CNKI, and Wanfang databases (all years up to January 2024). Efficacy and safety outcomes were evaluated using odds ratio (OR) and 95% confidence intervals (CI). The Surface Under the Cumulative Ranking (SUCRA) probabilities were used to rank each intervention. Among 14,056 studies screened, 56 studies involving 9792 participants were analyzed. Vonoprazan demonstrated the best efficacy in ulcer healing rate and H. pylori eradication rate (SUCRA = 86.4% and 90.7%, respectively). Keverprazan ranked second in ulcer healing rates (SUCRA = 76.0%) and was more effective in pain remission rates (SUCRA = 91.7%). The risk of adverse events was low for keverprazan (SUCRA = 11.8%) and tegoprazan (SUCRA = 12.9%), and moderate risk for vonoprazan (SUCRA = 44.3%) was demonstrated. Compared to lansoprazole, vonoprazan exhibited a higher risk of drug-related adverse events (OR: 2.15; 95% CI: 1.60-2.89) and serious adverse events (OR: 2.22; 95% CI: 1.11-4.42). Subgroup analysis on patients with H. pylori-positive peptic ulcers showed that vonoprazan was at the top of the SUCRA rankings, followed by keverprazan. Vonoprazan showed superior performance in peptic ulcers, especially for patients with H. pylori-positive peptic ulcers. However, the risk of adverse events associated with vonoprazan should be noted. Keverprazan has also shown good therapeutic outcomes and has performed better in terms of safety.

5.
Eur J Pharmacol ; 978: 176704, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38830458

RESUMO

Finding new and effective natural products for designing antiepileptic drugs is highly important in the scientific community. The scorpion venom heat-resistant peptide (SVHRP) was purified from Buthus martensii Karsch scorpion venom, and subsequent analysis of the amino acid sequence facilitated the synthesis of a peptide known as scorpion venom heat-resistant synthesis peptide (SVHRSP) using a technique for peptide synthesis. Previous studies have demonstrated that the SVHRSP can inhibit neuroinflammation and provide neuroprotection. This study aimed to investigate the antiepileptic effect of SVHRSP on both acute and chronic kindling seizure models by inducing seizures in male rats through intraperitoneal administration of pentylenetetrazole (PTZ). Additionally, an N-methyl-D-aspartate (NMDA)-induced neuronal injury model was used to observe the anti-excitotoxic effect of SVHRSP in vitro. Our findings showed that treatment with SVHRSP effectively alleviated seizure severity, prolonged latency, and attenuated neuronal loss and glial cell activation. It also demonstrated the prevention of alterations in the expression levels of NMDA receptor subunits and phosphorylated p38 MAPK protein, as well as an improvement in spatial reference memory impairment during Morris water maze (MWM) testing in PTZ-kindled rats. In vitro experiments further revealed that SVHRSP was capable of attenuating neuronal action potential firing, inhibiting NMDA receptor currents and intracellular calcium overload, and reducing neuronal injury. These results suggest that the antiepileptic and neuroprotective effects of SVHRSP may be mediated through the regulation of NMDA receptor function and expression. This study provides new insight into therapeutic strategies for epilepsy.

6.
Sci Adv ; 10(26): eado6798, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38941458

RESUMO

Oral medication for ulcerative colitis (UC) is often hindered by challenges such as inadequate accumulation, limited penetration of mucus barriers, and the intricate task of mitigating excessive ROS and inflammatory cytokines. Here, we present a strategy involving sodium alginate microspheres (SAMs) incorporating M2 macrophage membrane (M2M)-coated Janus nanomotors (denominated as Motor@M2M) for targeted treatment of UC. SAM provides a protective barrier, ensuring that Motor@M2M withstands the harsh gastric milieu and exhibits controlled release. M2M enhances the targeting precision of nanomotors to inflammatory tissues and acts as a decoy for the neutralization of inflammatory cytokines. Catalytic decomposition of H2O2 by MnO2 in the oxidative microenvironment generates O2 bubbles, propelling Motor@M2M across the mucus barrier into inflamed colon tissues. Upon oral administration, Motor@M2M@SAM notably ameliorated UC severity, including inflammation mitigation, ROS scavenging, macrophage reprogramming, and restoration of the intestinal barrier and microbiota. Consequently, our investigation introduces a promising oral microsphere formulation of macrophage-biomimetic nanorobots, providing a promising approach for UC treatment.


Assuntos
Alginatos , Colite Ulcerativa , Macrófagos , Microesferas , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Animais , Administração Oral , Camundongos , Alginatos/química , Humanos , Modelos Animais de Doenças , Espécies Reativas de Oxigênio/metabolismo , Nanopartículas/química , Sistemas de Liberação de Medicamentos , Peróxido de Hidrogênio/metabolismo
7.
Liver Int ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38924592

RESUMO

BACKGROUND & AIMS: Intrahepatic cholangiocarcinoma (iCCA) has two main histological subtypes: large and small duct-type iCCA, which are characterized by different clinicopathological features. This study was conducted with the purpose of expanding our understanding of their differences in molecular features and immune microenvironment. METHODS: We selected 132 patients who underwent radical surgery at our department between 2015 and 2021 for clinical and survival analyses. Whole-exome sequencing was performed to analyse mutational landscapes. Bulk RNA sequencing and single-cell RNA sequencing data were used for pathway enrichment and immune infiltration analyses based on differentially expressed genes. The function of PPP1R1B was analysed both in vitro and in vivo and the gene mechanism was further investigated. RESULTS: We found that large duct-type iCCA had worse overall survival and recurrence-free survival rates than small duct-type iCCA. Mutations in ARID1A, DOT1L and ELF3 usually occur in large duct-type iCCA, whereas mutations in IDH1 and BAP1 occur in small duct-type iCCA. Among the differentially expressed genes, we found that PPP1R1B was highly expressed in large duct-type iCCA tumour tissues. Expression of PPP1R1B promoted cell proliferation, migration and invasion and indicated a worse prognosis. A combination of USF2 with the promoter of PPP1R1B can enhance gene expression in iCCA, which may further affect the expression of genes such as AHNAK, C4BPA and activating the PI3K/AKT pathway. CONCLUSIONS: Our findings extend our understanding of large and small duct-type iCCA. In addition, PPP1R1B may serve as a potential marker and therapeutic target for large duct-type iCCA.

8.
J Am Chem Soc ; 146(21): 14754-14764, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38754363

RESUMO

Lithium-sulfur (Li-S) batteries are highly considered as next-generation energy storage techniques. Weakly solvating electrolyte with low lithium polysulfide (LiPS) solvating power promises Li anode protection and improved cycling stability. However, the cathodic LiPS kinetics is inevitably deteriorated, resulting in severe cathodic polarization and limited energy density. Herein, the LiPS kinetic degradation mechanism in weakly solvating electrolytes is disclosed to construct high-energy-density Li-S batteries. Activation polarization instead of concentration or ohmic polarization is identified as the dominant kinetic limitation, which originates from higher charge-transfer activation energy and a changed rate-determining step. To solve the kinetic issue, a titanium nitride (TiN) electrocatalyst is introduced and corresponding Li-S batteries exhibit reduced polarization, prolonged cycling lifespan, and high actual energy density of 381 Wh kg-1 in 2.5 Ah-level pouch cells. This work clarifies the LiPS reaction mechanism in protective weakly solvating electrolytes and highlights the electrocatalytic regulation strategy toward high-energy-density and long-cycling Li-S batteries.

9.
JGH Open ; 8(5): e13070, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38699469

RESUMO

Background and Aim: To evaluate the efficacy and safety of minocycline, vonoprazan, amoxicillin, and bismuth quadruple therapy for Helicobacter pylori (H. pylori) treatment. Methods: From August 2022 to May 2023, clinical data were collected from patients who received H. pylori eradication treatment at West China Fourth Hospital, Sichuan University. One group received the MVAB regimen (amoxicillin, minocycline, vonoprazan, and colloidal bismuth pectin), while another group received the FOAB regimen (amoxicillin, furazolidone, omeprazole, and colloidal bismuth pectin), both administered for 14 days. Follow-up assessments of safety and compliance were conducted within 1 week after treatment completion. One and a half months after treatment, the success of eradication was evaluated using the urea breath test. Results: For the MVAB regimen as a first-line treatment, the eradication rate was 90.1% (127/141, 95% CI: 85.1-95.1%) in the ITT analysis and 93.4% (127/136, 95% CI: 89.2-97.6%) in the PP analysis as a first-line treatment. As a second-line treatment, the eradication rate was 91.3% (21/23, 95% CI: 78.8-103.8%) in both analyses. For the FOAB regimen as a first-line treatment, the eradication rate was 98.0% (50/51, 95% CI: 94.1-101.2%) in the ITT analysis and 100% (50/50, 95% CI: 100%) in the PP analysis. As a second-line treatment, the eradication rate was 100% (6/6, 95% CI: 100%) in both analyses. Moreover, there was no significant difference in the incidence of adverse events between the two groups (MVAB regimen: 5.5% and FOAB regimen: 8.8%; P > 0.05). Conclusions: The MVAB regimen could indeed be a viable alternative treatment option to conventional therapies.

10.
Nat Commun ; 15(1): 3652, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714661

RESUMO

Materials following Murray's law are of significant interest due to their unique porous structure and optimal mass transfer ability. However, it is challenging to construct such biomimetic hierarchical channels with perfectly cylindrical pores in synthetic systems following the existing theory. Achieving superior mass transport capacity revealed by Murray's law in nanostructured materials has thus far remained out of reach. We propose a Universal Murray's law applicable to a wide range of hierarchical structures, shapes and generalised transfer processes. We experimentally demonstrate optimal flow of various fluids in hierarchically planar and tubular graphene aerogel structures to validate the proposed law. By adjusting the macroscopic pores in such aerogel-based gas sensors, we also show a significantly improved sensor response dynamics. In this work, we provide a solid framework for designing synthetic Murray materials with arbitrarily shaped channels for superior mass transfer capabilities, with future implications in catalysis, sensing and energy applications.

11.
Oral Oncol ; 154: 106860, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38801787

RESUMO

OBJECTIVES: The deep circumflex iliac artery flap (DCIA) and vascularized fibular free flap (FFF) are mainstay flaps for maxillary defect reconstruction. This study compared the functional outcomes and success rates of these flaps to provide midface reconstruction strategies. MATERIALS AND METHODS: Maxillary defects reconstructed with DCIA or FFF at the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology between May 2016 and May 2023 were retrospectively analyzed. The length, width, and height of the grafted bone segments; intermaxillary distance; buttress reconstruction rate (BRR); dental arch reconstruction rate (DAR); success rate; and dental implantation rate were compared. RESULTS: The DCIA and FFF groups had 33 and 27 patients, respectively. Success rate in the DCIA group was 93.94 % and 100 % in the FFF group. The DCIA length was less than that of FFF; however, the width and height were significantly larger. 87.10 % of cases in the DCIA group were classified as Brown class b and c, 51.85 % of cases in the FFF group were classified as Brown class d. The average BRR in the DCIA group was 69.89 % ± 16.05 %, which was significantly higher than that in the FFF group. A total of 38.7 % and 11.1 % patients in the DCIA and FFF groups, respectively, had completed implantation. CONCLUSION: DCIA has a greater width and height, and is more suitable for repairing Brown class b and c defects, providing sufficient bone for implantation, while the FFF is longer and more suitable for Brown class d defect reconstruction.


Assuntos
Fíbula , Retalhos de Tecido Biológico , Artéria Ilíaca , Maxila , Procedimentos de Cirurgia Plástica , Humanos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Artéria Ilíaca/cirurgia , Artéria Ilíaca/transplante , Fíbula/transplante , Procedimentos de Cirurgia Plástica/métodos , Maxila/cirurgia , Adulto , Idoso
13.
Front Cell Infect Microbiol ; 14: 1378804, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38736749

RESUMO

Introduction: Seasonal human coronavirus NL63 (HCoV-NL63) is a frequently encountered virus linked to mild upper respiratory infections. However, its potential to cause more severe or widespread disease remains an area of concern. This study aimed to investigate a rare localized epidemic of HCoV-NL63-induced respiratory infections among pediatric patients in Guilin, China, and to understand the viral subtype distribution and genetic characteristics. Methods: In this study, 83 pediatric patients hospitalized with acute respiratory infections and positive for HCoV-NL63 were enrolled. Molecular analysis was conducted to identify the viral subgenotypes and to assess genetic variations in the receptor-binding domain of the spiking protein. Results: Among the 83 HCoV-NL63-positive children, three subgenotypes were identified: C4, C3, and B. Notably, 21 cases exhibited a previously unreported subtype, C4. Analysis of the C4 subtype revealed a unique amino acid mutation (I507L) in the receptor-binding domain of the spiking protein, which was also observed in the previously reported C3 genotype. This mutation may suggest potential increases in viral transmissibility and pathogenicity. Discussion: The findings of this study highlight the rapid mutation dynamics of HCoV-NL63 and its potential for increased virulence and epidemic transmission. The presence of a unique mutation in the C4 subtype, shared with the C3 genotype, raises concerns about the virus's evolving nature and its potential public health implications. This research contributes valuable insights into the understanding of HCoV-NL63's epidemiology and pathogenesis, which is crucial for effective disease prevention and control strategies. Future studies are needed to further investigate the biological significance of the observed mutation and its potential impact on the virus's transmissibility and pathogenicity.


Assuntos
Infecções por Coronavirus , Coronavirus Humano NL63 , Epidemias , Genótipo , Filogenia , Infecções Respiratórias , Humanos , Coronavirus Humano NL63/genética , China/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Infecções por Coronavirus/transmissão , Criança , Feminino , Masculino , Pré-Escolar , Infecções Respiratórias/virologia , Infecções Respiratórias/epidemiologia , Lactente , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Estações do Ano , Mutação , Adolescente
14.
Heliyon ; 10(9): e30399, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38726206

RESUMO

As a new type of agricultural waste block substrate utilization, the initial wet base state of the substrate culture block needs to be dried. Therefore, studying the drying mechanism of substrate culture block is critical. In this study, the substrate culture block in a dry state was taken as the research object. Based on physical and chemical properties, the internal section of the substrate culture block was characterized by scanning electron microscopy and the pore condition of the particles was quantified. The results showed that the internal pore structure was uniform and favorable for plant root growth. Based on the pore structure, pore channel modeling was constructed to investigate the distribution of the internal multiphase medium and to distinguish between channels and pore-blind channels. The applicability of the modeling was verified and discussed. By measuring the drying rate of the substrate culture block and classifying its drying stages as fast speed, constant speed, and slow speed, it is clarified that the forms of moisture existence are bound-state water and free-state water, and the moisture migration is prioritized as surface adsorption water, interparticle water, particle attached water, and capillary water. Innovate a method to quantify the change of pore space in the drying process by pore coefficient ratio to evaluate the drying quality. The results show that when the pore coefficient ratio is about 40 %, its moisture content is 20 %∼30 %, and the drying effect is best at this time. The physical drying test further confirmed the correctness of the conclusion of the drying stage division and water loss law. This study can provide a theoretical reference for the modeling study of the pore structure of the block matrix and the exploration of its drying mechanism.

15.
Nano Lett ; 24(17): 5308-5316, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38647008

RESUMO

FAPbI3 stands out as an ideal candidate for the photoabsorbing layer of perovskite solar cells (PSCs), showcasing outstanding photovoltaic properties. Nonetheless, stabilizing photoactive α-FAPbI3 remains a challenge due to the lower formation energy of the competitive photoinactive δ-phase. In this study, we employ tetraethylphosphonium lead tribromide (TEPPbBr3) single crystals as templates for the epitaxial growth of PbI2. The strategic use of TEPPbBr3 optimizes the evolution of intermediates and the crystallization kinetics of perovskites, leading to high-quality and phase-stable α-FAPbI3 films. The TEPPbBr3-modified perovskite exhibits optimized carrier dynamics, yielding a champion efficiency of 25.13% with a small voltage loss of 0.34 V. Furthermore, the target device maintains 90% of its initial PCE under maximum power point (MPP) tracking over 1000 h. This work establishes a promising pathway through single crystal seed based epitaxial growth for achieving satisfactory crystallization regulation and phase stabilization of α-FAPbI3 perovskites toward high-efficiency and stable PSCs.

16.
Expert Opin Drug Saf ; 23(5): 637-648, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38564277

RESUMO

OBJECTIVES: To explore the association between palbociclib and related adverse events (AEs) in the real world through U.S. Food and Drug Administration Adverse Event Reporting System (FAERS) database. METHODS: The signal strength of palbociclib-related AEs was done by disproportionality analysis. Clinical priority of palbociclib-related AEs was scored and ranked by assessing five different features. Outcome analysis, time to onset analysis, dose-report /AEs number analysis, and stratification analysis were all performed. RESULTS: There were 61,821 'primary suspected (PS)' reports of palbociclib and 195,616 AEs associated with palbociclib. The four algorithms simultaneously detected 18 positive signals at the SOC level, and 65 positive signals at the PT level. Bone marrow failure, neuropathy, peripheral, pleural effusion, myelosuppression, pulmonary edema, and pulmonary thrombosis were also found to have positive signals. Gender (female vs male, χ2 = 5.287, p = 0.022) and age showed significant differences in serious and non-serious reports. Palbociclib-related AEs had a median onset time of 79 days (interquartile range [IQR] 20-264 days). CONCLUSIONS: The study identified potential Palbociclib-related AEs and offered warnings for special AEs, providing further data for palbociclib safety studies in breast cancer patients. Nonetheless, prospective clinical trials are needed to validate these results and explain their relationship.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos , Antineoplásicos , Bases de Dados Factuais , Piperazinas , Vigilância de Produtos Comercializados , Piridinas , United States Food and Drug Administration , Piridinas/efeitos adversos , Piridinas/administração & dosagem , Humanos , Piperazinas/efeitos adversos , Piperazinas/administração & dosagem , Masculino , Sistemas de Notificação de Reações Adversas a Medicamentos/estatística & dados numéricos , Feminino , Estados Unidos , Pessoa de Meia-Idade , Idoso , Antineoplásicos/efeitos adversos , Antineoplásicos/administração & dosagem , Adulto , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/administração & dosagem , Algoritmos , Fatores Sexuais , Idoso de 80 Anos ou mais , Fatores Etários , Fatores de Tempo , Adulto Jovem , Relação Dose-Resposta a Droga
17.
Int J Biol Macromol ; 267(Pt 1): 131321, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38570001

RESUMO

The improper usage of levofloxacin (LEV) endangers both environmental safety and human public health. Therefore, trace analysis and detection of LEV have extraordinary significance. In this paper, a novel molecularly imprinted polymer (MIP) electrochemical sensor was developed for the specific determination of LEV by electrochemical polymerization of o-phenylenediamine (o-PD) using poly(3,4-ethylenedioxythiophene)/chitosan (PEDOT/CS) with a porous structure and rich functional groups as a carrier and LEV as a template molecule. The morphology, structure and properties of the modified materials were analyzed and studied. The result showed that the electron transfer rate and the electroactive strength of the electrode surface are greatly improved by the interconnection of PEDOT and CS. Meanwhile, PEDOT/CS was assembled by imprinting with o-PD through non-covalent bonding, which offered more specific recognition sites and a larger surface area for the detection of LEV and effectively attracted LEV through intermolecular association. Under the optimized conditions, MIP/PEDOT/CS/GCE showed good detection performance for LEV in a wide linear range of 0.0019- 1000 µM, with a limit of detection (LOD, S/N = 3) of 0.4 nM. Furthermore, the sensor has good stability and selectivity, and exhibits excellent capabilities in the microanalysis of various real samples.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes , Quitosana , Técnicas Eletroquímicas , Levofloxacino , Impressão Molecular , Polímeros Molecularmente Impressos , Polímeros , Quitosana/química , Levofloxacino/análise , Levofloxacino/química , Polímeros/química , Compostos Bicíclicos Heterocíclicos com Pontes/química , Impressão Molecular/métodos , Técnicas Eletroquímicas/métodos , Polímeros Molecularmente Impressos/química , Eletrodos , Limite de Detecção , Humanos
18.
Food Chem ; 449: 139114, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38581782

RESUMO

L-Tryptophan (L-Trp) is essential for the human body and can only be obtained externally. It is important to develop a method to efficiently detect L-Trp in food. In this work, ionic liquid (IL) modified poly(3,4-ethylendioxythiophene)/ Titanium carbide (PEDOT/Ti3C2TX) was used as a substrate material to improve detection sensitivity. Molecular imprinted polymers (MIP) film for specific recognition of L-Trp was fabricated on the surface of modified electrodes using electrochemical polymerization. The monitoring results showed that the molecularly imprinted electrochemical sensors (MIECS) exhibited good linearity ranges (10-6 - 0.1 µM and 0.1-100 µM) with a low detection limit (LOD) of 2.09 × 10-7 µM. In addition, the MIECS exhibited remarkable stability, reproducibility, and immunity to interference. A good recovery (93.54-99.59%) was demonstrated in the detection of milk. The sensor was expected to be developed as a highly selective and sensitive portable assay, and applied to the detection of L-Trp in food.


Assuntos
Técnicas Eletroquímicas , Líquidos Iônicos , Limite de Detecção , Leite , Impressão Molecular , Polímeros , Titânio , Triptofano , Leite/química , Líquidos Iônicos/química , Polímeros/química , Animais , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Triptofano/análise , Triptofano/química , Titânio/química , Compostos Bicíclicos Heterocíclicos com Pontes/química , Polímeros Molecularmente Impressos/química , Contaminação de Alimentos/análise , Eletrodos , Reprodutibilidade dos Testes
19.
Polymers (Basel) ; 16(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38611230

RESUMO

The treatment of waste plastics has gradually become a hot topic in the current scientific community. In response to the needs for high-impact performance R-PP-based composites, carbon fiber (CF)-reinforced polyolefin elastomer (POE)/recycled polypropylene (R-PP) composite (CF/POE/R-PP) was prepared by the mechanical blending method, and its mechanical and thermal properties were systematically studied. It was found that the CF could effectively improve the bending and notch impact strength as well as enhance the thermal stability of POE/R-PP. Furthermore, a stable and dispersed composite interface formed by the combination of maleic anhydride-grafted polypropylene (PP-g-MAH) with the surface of CF and the fusion alkyl chains in R-PP and POE further enhanced the CF's reinforcing effect. As a result, the addition of 9 wt.% CF successfully improved the heat resistance of the composite material, and the residual carbon content increased by 97.84% after sintering. The composite toughening of POE and CF effectively improved the impact strength of the composite material, with a maximum increase of over 1000%. This study ultimately resulted in a high-impact-resistant composite material.

20.
J Colloid Interface Sci ; 667: 136-146, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38636215

RESUMO

Breaking through the limitations of lithium-ion transmission is imperative for high-power rechargeable batteries. As a promising anode material for fast-charging lithium-ion batteries (LIBs), niobium pentoxide (Nb2O5) has garnered considerable research attention due to its exceptional rate performance, stable lithium storage performance and high safety attributes. Nevertheless, the limited intrinsic conductivity of Nb2O5, coupled with its structural degradation during the cycling process, imposes constraints on its viability as a commercially viable electrode material. Herein, a ruthenium (Ru) doping method is employed to regulate the oxygen defects and the interlayer spacing of the tetragonal Nb2O5 (M-Nb2O5), offering superior reaction kinetics, higher stability for lithium storage sites and more unobstructed lithium-ion transport channels. Ru-doped Nb2O5 (RNO) manifests excellent electrochemical properties, including remarkable rate capacity (166 mAh/g at 80C), reversible capacity (246.98 mAh/g at 0.5C), improved initial Coulombic efficiency (95.77 % compared to 81.44 % of the pure sample) and cycling stability (maintaining a capacity of 113.5 mAh/g at 10C for 2,000 cycles). The enhancement mechanism of Ru doping on the structural stability and ion transport kinetics in tetragonal Nb2O5 is comprehensively elucidated through diverse electrochemical analyses and in-situ techniques.

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