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1.
Anal Chem ; 96(23): 9370-9378, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38683892

RESUMO

The development of sensors for detection of biomarkers exhibits an exciting potential in diagnosis of diseases. Herein, we propose a novel electrochemical sensing strategy for label-free dual-biomarker detection, which is based on the combination of stimulus-responsive molecularly imprinted polymer (MIP)-modified nanopores and a polymeric membrane chronopotentiometric sensor. The ion fluxes galvanostatically imposed on the sensing membrane surface can be blocked by the recognition reaction between the target biomarker in the sample solution and the stimulus-responsive MIP receptor in the nanopores, thus causing a potential change. By using two external stimuli (i.e., pH and temperature), the recognition abilities of the stimulus-responsive MIP receptor can be effectively modulated so that dual-biomarker label-free chronopotentiometric detection can be achieved. Using alpha fetoprotein (AFP) and prostate-specific antigen (PSA) as model biomarkers, the proposed sensor offers detection limits of 0.17 and 0.42 ng/mL for AFP and PSA, respectively.


Assuntos
Biomarcadores , Polímeros Molecularmente Impressos , Nanoporos , Antígeno Prostático Específico , alfa-Fetoproteínas , Antígeno Prostático Específico/análise , Polímeros Molecularmente Impressos/química , alfa-Fetoproteínas/análise , Humanos , Biomarcadores/análise , Limite de Detecção , Técnicas Eletroquímicas/métodos , Concentração de Íons de Hidrogênio , Técnicas Biossensoriais/métodos , Potenciometria/métodos , Polímeros/química , Impressão Molecular , Temperatura
2.
Analyst ; 149(6): 1738-1745, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38324339

RESUMO

Carrier-based polymeric membrane potentiometric sensors are an ideal tool for detecting ionic species. However, in the fabrication of these sensors, the screening of carriers still relies on empirical trial- and error-based optimization, which requires tedious and time-consuming experimental verification. In this work, computer-aided screening of carriers is applied in the preparation of polymeric membrane potentiometric sensors. Molecular docking is used to study the host-guest interactions between receptors and targets. Binding energies are employed as the standard to screen the appropriate carrier. As a proof-of-concept experiment, the antibiotic ciprofloxacin is selected as the target model. A series of supramolecular macrocyclic receptors including cyclodextrins, cucurbiturils and calixarenes are chosen as potential receptors. The proposed sensor based on the receptor calix[4]arene screened by molecular docking shows a lower detection limit of 0.5 µmol L-1 for ciprofloxacin. It can be expected that the proposed computer-aided screening technique of carriers can provide a simple but highly efficient method for the fabrication of carrier-based electrochemical and optical sensors.


Assuntos
Calixarenos , Compostos Macrocíclicos , Antibacterianos , Simulação de Acoplamento Molecular , Potenciometria , Compostos Macrocíclicos/química , Polímeros/química , Calixarenos/química , Ciprofloxacina
3.
Mikrochim Acta ; 191(6): 356, 2024 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811412

RESUMO

Charged antimicrobial peptides can be used for direct potentiometric biosensing, but have never been explored. We report here a galvanostatically-controlled potentiometric sensor for antimicrobial peptide-based biosensing. Solid-state pulsed galvanostatic sensors that showed excellent stability under continuous galvanostatic polarization were prepared by utilizing reduced graphene oxide/poly (3,4-ethylenedioxythiophene): poly (4-styrenesulfonate) (rGO/PEDOT: PSS) as a solid contact. More importantly, the chronopotentiometric sensor can be made sensitive to antimicrobial peptides with intrinsic charge on demand via a current pulse. In this study, a positively charged antimicrobial peptide that can bind to Staphylococcus aureus with high affinity and good selectivity was designed as a model. Two arginine residues with positive charges were linked to the C-terminal of the peptide sequence to increase its potentiometric responses on the electrode. The bacteria binding-induced charge or charge density change of the antimicrobial peptide enables the direct chronopotentiometric detection of the target. Under the optimized conditions, the concentration of Staphylococcus aureus can be determined in the linear range 10-1.0 × 105 CFU mL-1 with a detection limit of 10 CFU mL-1. It is anticipated that such a chronopotentiometric sensing platform is readily adaptable to detect other bacteria by choosing the peptides.


Assuntos
Técnicas Biossensoriais , Grafite , Potenciometria , Staphylococcus aureus , Técnicas Biossensoriais/métodos , Grafite/química , Potenciometria/métodos , Peptídeos Antimicrobianos/química , Peptídeos Antimicrobianos/farmacologia , Limite de Detecção , Polímeros/química , Compostos Bicíclicos Heterocíclicos com Pontes/química , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Eletrodos
4.
Acta Odontol Scand ; 83: 348-355, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38860278

RESUMO

OBJECTIVE: It is evident that periodontitis is linked to various adverse pregnancy outcomes. This prospective study explored the potential link of maternal periodontal diseases to neonatal adverse outcomes. MATERIALS AND METHODS: A total of 193 generally healthy females in their third trimester (34-36 weeks) of pregnancy were enrolled. All subjects received full-mouth periodontal assessment, and the periodontal inflamed surface area (PISA) was calculated. Demographic data, lifestyles and anthropometric measurements of the neonates (e.g., body length and head circumference) were recorded. Herein, small-for-gestational age (SGA) referred to gender- and age-adjusted birth weight below the 10th percentile in line with the standard reference. Multivariable logistic regression analysis and restricted cubic spline were performed for examining the association of periodontal parameters with SGA.  Results: There were 8.3% (16/193) of neonates with SGA. Significantly positive correlation existed between the percentage of tooth sites with increased probing depth and an elevated risk of SGA (OR: 1.052; P < 0.05). Yet, the PISA was positively associated with the risk of SGA (OR: 1.002; P < 0.05) as well. No significant link occurred between maternal periodontal status and other neonatal outcome measures. CONCLUSION: Within the limitations of this study, the findings suggest that there could be a link between maternal periodontal diseases and neonatal adverse outcomes like SGA. Further investigation is required to clarify the current findings and potential implications for promoting maternal oral/periodontal health and newborn health.


Assuntos
Recém-Nascido Pequeno para a Idade Gestacional , Doenças Periodontais , Resultado da Gravidez , Humanos , Feminino , Estudos Prospectivos , Gravidez , Recém-Nascido , Doenças Periodontais/complicações , Adulto , Complicações na Gravidez
5.
J Nanobiotechnology ; 21(1): 379, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37848975

RESUMO

BACKGROUND: Brain-derived neurotrophic factor (BDNF) with neuronic development and function is a promising therapeutic agent for treating depressive disorder, according to the neurotrophin hypothesis. However, the delivery of BDNF into the brain is not easy as these large protein molecules cannot efficiently cross the blood-brain barrier (BBB) and easily suffer oxidative damage in vivo. Therefore, the quercetin-based alginate nanogels (quercetin nanogels) loaded with BDNF have been developed, which could efficiently bypass the BBB via the nose-to-brain pathway and protect BDNF from oxidative damage, providing an effective route for the therapy of depressive disorders by intranasal delivery. RESULTS: Quercetin nanogels exhibited uniform size distribution, excellent biocompatibility, and potent antioxidant and anti-inflammatory activities. Quercetin nanogels in the thermosensitive gel achieved sustained and controlled release of BDNF with non-Fick's diffusion, exhibited rapid brain distribution, and achieved nearly 50-fold enhanced bioavailability compared to oral quercetin. Quercetin nanogels as a therapeutic drug delivery carrier exerted antidepressant effects on reserpine-induced rats, effectively delivered BDNF to reverse despair behavior in stress-induced mice, and exhibited antidepressant effects on chronic mild unpredictable stimulation (CUMS) rats. These antidepressant effects of BDNF-Quercetin nanogels for CUMS rats are associated with the regulation of the glutamatergic system, PI3K-Akt, and BDNF-TrkB signaling pathway. CONCLUSIONS: In this study, we provide a promising strategy for brain delivery of BDNF for treating depressive disorders, effectively achieved through combining quercetin nanogels and intranasal administration.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Quercetina , Ratos , Camundongos , Animais , Quercetina/farmacologia , Quercetina/uso terapêutico , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Depressão/tratamento farmacológico , Depressão/metabolismo , Nanogéis , Alginatos , Fosfatidilinositol 3-Quinases/metabolismo , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Antidepressivos/metabolismo , Hipocampo , Modelos Animais de Doenças
6.
Angew Chem Int Ed Engl ; 62(3): e202210513, 2023 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-36404278

RESUMO

Bioelectronic sensors that report charge changes of a biomolecule upon target binding enable direct and sensitive analyte detection but remain a major challenge for potentiometric measurement, mainly due to Debye Length limitations and the need for molecular-level platforms. Here, we report on a magneto-controlled potentiometric method to directly and sensitively measure the target-binding induced charge change of DNA aptamers assembled on magnetic beads using a polymeric membrane potentiometric ion sensor. The potentiometric responses of the negatively charged aptamer, serving as a receptor and reporter, were dynamically controlled and modulated by applying a magnetic field. Based on a potentiometric array, this non-equilibrium measurement technique combined with deep learning algorithms allows for rapidly and reliably classifying and quantifying diverse small molecules using antibiotics as models. This potentiometric strategy opens new modalities for sensing applications.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Aprendizado Profundo , Aptâmeros de Nucleotídeos/química , Antibacterianos , Potenciometria/métodos , Polímeros , Técnicas Biossensoriais/métodos
7.
Anal Chem ; 94(22): 7795-7803, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35593704

RESUMO

Molecularly imprinted polymer (MIP)-based polymeric membrane potentiometric sensors have become an attractive tool for detection of organic species. However, the MIP receptors in potentiometric sensors developed so far are usually prepared by only using single functional monomers. This may lead to low affinities of the MIP receptors due to the lack of diversity of the functional groups, thus resulting in low detection sensitivity of the potentiometric sensors. Additionally, these classical MIP receptors are nonconductive polymers, which are undesirable for the fabrication of an electrochemical sensor. Herein, we describe a novel multifunctional MIP receptor-based potentiometric sensor. The multifunctional MIP receptor is prepared by using two functional monomers, methacrylic acid, and 3-vinylaniline with a dual functionality of both recognition and conduction properties. The poly(aniline) groups are introduced into the methacrylic acid-based MIP by postoxidation of the aniline monomer. Such poly(aniline) groups not only serve as the additional functional groups for selective recognition, but also work as a conducting polymer. The obtained multifunctional MIP receptor shows a high binding capacity and an excellent electron-transfer ability. By using bisphenol A as a model, the proposed multifunctional MIP sensor exhibits a largely improved sensitivity and low noise levels compared to the conventional MIP sensor. We believe that the proposed MIP-based sensing strategy provides a general and facile way to fabricate sensitive and selective MIP-based electrochemical sensors.


Assuntos
Impressão Molecular , Compostos de Anilina , Compostos Benzidrílicos , Técnicas Eletroquímicas/métodos , Eletrodos , Limite de Detecção , Impressão Molecular/métodos , Polímeros Molecularmente Impressos , Fenóis , Polímeros/química , Potenciometria/métodos
8.
Anal Chem ; 94(34): 11916-11924, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-35980333

RESUMO

Environmentally compatible polymeric membrane marine sensors with excellent antiadhesive and antibacterial properties have recently been developed. However, the regeneration abilities of these sensors after fouling have rarely been investigated. Herein, a novel strategy for preparation of a regenerable antibiofouling coating via surface modification of a dual-functionalized magnetic composite is proposed. A zwitterionic polymer (i.e., poly(sulfobetaine methacrylate)) and a quaternary ammonium compound (i.e., 3-trimethoxysilylpropyl octadecyldimethyl ammonium chloride) are coated on the surface of Fe3O4 microspheres for antiadhesion and bacterial inactivation, respectively. The antifouling magnetic composite can readily be modified on the sensor's surface via the magnetically assisted self-assembly technology. Using a polymeric membrane calcium ion-selective electrode as a model sensor, the protection layer-coated electrode shows the markedly improved antibiofouling activities as compared to the unmodified sensor. More importantly, by altering the direction of the external magnetic field, the antifouling coating can easily be removed after fouling along with the removal of the adsorbed bacterial cells from the electrode's surface, which is followed by re-modifying a fresh coating for regeneration of the antifouling electrode. The proposed methodology for fabrication of a regenerable antibiofouling coating is promising to improve the durability of a marine sensor.


Assuntos
Aderência Bacteriana , Polímeros , Fenômenos Magnéticos , Metacrilatos , Compostos de Amônio Quaternário , Propriedades de Superfície
9.
Anal Chem ; 93(18): 6932-6937, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33914516

RESUMO

Due to the frequent oil spill accidents and pollution of industrial oily wastewater, oil fouling has become a great challenge to polymeric membrane ion-selective electrodes (ISEs) for applications in oil-contaminated areas. Herein, a simple approach is proposed to enhance the oil-fouling resistance of polymeric membrane ISEs by surface modification of a zwitterionic polymer-based underwater oleophobic coating. As a proof-of-concept, a classical poly(vinyl chloride) membrane-based calcium ion-selective electrode (Ca2+-ISE) is chosen as a model sensor. The zwitterionic polymer-based coating can be readily modified on the sensor's surface by immersion of the electrode into a mixture solution of dopamine and a zwitterionic acrylate monomer (i.e., sulfobetaine methacrylate, SBMA). The formed poly(SBMA) (PSBMA) coating alters the oleophilic membrane surface to an oleophobic one, which endows the surface with excellent self-cleaning properties without loss of the sensor's analytical performance. Compared to the pristine Ca2+-ISE, the PSBMA-modified Ca2+-ISE exhibits an improved analytical stability when exposed to oil-containing wastewater. The proposed approach can be explored to enhance the oil-fouling resistance of other polymeric membrane-based electrochemical sensors for use in the oil-polluted environment.


Assuntos
Eletrodos Seletivos de Íons , Polímeros , Metacrilatos , Águas Residuárias
10.
Angew Chem Int Ed Engl ; 60(5): 2609-2613, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33021005

RESUMO

We report here the concept of a magnetically controlled extraction of hydrophilic bioreceptors into polymeric membranes for bioassays. The potentiometric assay relies on the intrinsic charges of an antimicrobial peptide and its unique recognition abilities, which can eliminate the probe labeling and indicator addition. The target binding event could effectively prevent the extraction of the peptide into the polymeric membrane doped with an ion exchanger, thus resulting in a potential change. The potentiometric response properties of the peptide assembled on magnetic beads can be dynamically controlled and modulated by applying a magnetic field. Staphylococcus aureus, as a model of food-borne pathogens, was measured at levels down to 10 CFU mL-1 . Based on this sensing strategy, a potentiometric array was developed for the pattern recognition of bacteria. The proposed general platform can be used for potentiometric biosensing using other hydrophilic bioreceptors.


Assuntos
Técnicas Biossensoriais/métodos , Polímeros/química , Potenciometria/métodos , Humanos
11.
Anal Chem ; 92(6): 4284-4291, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32090538

RESUMO

Nowadays, polymeric membrane potentiometric sensors based on the molecularly imprinted polymers (MIPs) have been successfully developed for detection of various organic and biological species. However, it is difficult for these sensors to perform reversible detection of the targets due to the high affinities of the MIPs toward the targets. In this work, we propose a novel method for fully reversible potentiometric detection of neutral phenols based on the stimulus-responsive MIP as the selective receptor. Since such smart receptor can switch its recognition abilities according to the external environmental stimuli, the MIP binding sites in the polymeric membrane can be regenerated via the stimulus after each measurement. Thus, potentiometric reversible detection of the target can be achieved. As a proof of concept, the pH-responsive MIP is used as the selective receptor, which can be synthesized by using 4-vinylphenylboronic acid as the functional monomer. The boronate-affinity MIP can covalently bind with a cis-diol containing compound to form a five- or six-membered cyclic ester in a weakly alkaline aqueous solution, while the produced ester dissociates when the surrounding pH is changed to acidic. By using catechol as a model, the proposed smart sensor exhibits a significantly improved reversibility compared to the conventional MIP-based sensor. We believed that the stimulus-responsive MIP-based sensing strategy could provide an appealing way to design reversible MIP-based electrochemical and optical sensors.


Assuntos
Polímeros Molecularmente Impressos/química , Fenóis/análise , Concentração de Íons de Hidrogênio , Estrutura Molecular , Tamanho da Partícula , Potenciometria , Propriedades de Superfície
12.
Anal Chem ; 92(18): 12132-12136, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32794703

RESUMO

A self-sterilizing strategy based on antimicrobial organic agent release is proposed for polymeric membrane sensors to prevent marine biofouling. A solid-contact polymeric membrane calcium ion-selective electrode (Ca2+-ISE) is selected as a model sensor. 6-Cholorindole (6-Cl indole) is utilized as the biocidal agent due to its potential antimicrobial activity and environmental friendliness. The plasticized polymeric membrane doped with 6-Cl indole shows a markedly improved antimicrobial activity against the bacterial cells collected from seawater and effectively prevents the formation of a biofilm on the sensor surface, while displaying response properties (i.e., linear range, selectivity, and response time) similar to those of the undoped membrane. Importantly, the present sensor can preserve an improved antimicrobial activity when kept in the artificial seawater for 45 days, indicating highly stable antibacterial properties of the membrane electrode. Additionally, the 6-Cl indole-doped Ca2+-ISE exhibits no significant loss of analytical performance after exposure to a rather concentrated bacterial suspension (∼109 colony-forming units per mL (CFU mL-1)) for 7 days. The proposed antimicrobial agent release methodology can be extended to develop polymeric membrane-based marine sensors with stable biofouling resistances against bacterial colonization.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Incrustação Biológica/prevenção & controle , Cálcio/química , Indóis/farmacologia , Cloreto de Polivinila/química , Antibacterianos/análise , Eletrodos , Indóis/análise
13.
Anal Chem ; 91(20): 13268-13274, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31525286

RESUMO

Improving the durability relating to biofouling resistance is still a major challenge for sensors applied in marine monitoring. Herein, a novel antifouling approach implementing biofouling resistance without compromising the sensor's performance is proposed. A polymeric membrane calcium ion-selective electrode (Ca2+-ISE) is chosen as a model sensor. An antifouling coating based on graphene oxide (GO) can be formed on the sensor's surface via the layer-by-layer technique in a simple and controllable manner. The GO coating works as a protection layer to impede the settlement of marine bacterial cells on the sensor surface due to its dual functionality of both antiadhesive and antimicrobial properties. The assembly of the GO coating does not influence the sensor's performance in terms of linear range and response slope. The biofouling resistance of the proposed sensor to marine bacterial cells is evaluated by using the colony-forming unit (CFU) counting method and confocal laser scanning microscopy analysis. An improved antimicrobial activity and a significant decrease in the adsorption of bacterial cells are observed for the GO-coated Ca2+-ISE. Moreover, negligible change is observed in the analysis performance of the GO-coated Ca2+-ISE after 7 day exposure to a rather high concentration marine bacterial suspension of ∼109 CFU mL-1. This work provides an efficient strategy of developing GO-based antifouling coatings to improve the environmental compatibility of marine sensors.


Assuntos
Antibacterianos/química , Incrustação Biológica/prevenção & controle , Técnicas Eletroquímicas/instrumentação , Grafite/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes/química , Cálcio/análise , Adesão Celular/efeitos dos fármacos , Técnicas Eletroquímicas/métodos , Grafite/farmacologia , Eletrodos Seletivos de Íons , Polímeros/química , Ácidos Sulfônicos/química
14.
Anal Chem ; 91(10): 6424-6429, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31034209

RESUMO

Polymeric membrane potentiometric ion sensors have been widely used in clinical diagnosis for the detection of electrolyte ions and account for billions of measurements every year throughout the world. However, in many cases of practical relevance, biofouling, which might lead to sensor failure, usually occurs due to the lack of biocompatibility of these sensors. Herein, we describe a simple and robust approach for improving the biocompatibility of the polymeric ion-selective membranes. A marine mussel-inspired polydopamine polymer is used as a hydrophilic coating on the surface of conventional potentiometric ion sensors. Such a coating can be easily formed by self-polymerization of dopamine and robustly deposited on the sensor surface mimicking the adhesion mechanism of mussels. The classical poly(vinyl chloride) membrane-based calcium ion-selective electrode (ISE) is chosen as a model. Compared to the unmodified Ca2+ ISE, the polydopamine modified electrode shows a significantly reduced blood platelet adsorption while retaining original potentiometric ion response properties, which clearly indicates a high antifouling capability induced by the hydrophilic polydopamine coating. We believe that the proposed approach can provide an appealing way to improve the biocompatibility in the development of polymeric membrane electrochemical and optical sensors.


Assuntos
Bivalves/química , Indóis/química , Teste de Materiais , Polímeros/química , Cloreto de Polivinila/química , Animais , Técnicas Biossensoriais , Plaquetas/fisiologia , Galinhas , Patos , Técnicas Eletroquímicas , Membranas Artificiais , Adesividade Plaquetária , Propriedades de Superfície
15.
BMC Infect Dis ; 19(1): 995, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31771520

RESUMO

BACKGROUND: In 2017, an outbreak of onychomadesis occurred in kindergarten H, Hubei province, China. We investigated the field to learn about the magnitude and reason of the outbreak. METHODS: The case definition was that a child with onychomadesis or transverse ridging (Beau's line) in fingernails and toenails without previous traumatic or systemic disease in kindergarten H from Sep. 1st to Nov. 30th, 2017. A retrospective cohort study was carried out to analyze the epidemiological relationship between onychomadesis and the hand-foot-mouth disease (HFMD) in Primary Class #2, kindergarten H. We also performed a serological survey for neutralizing antibodies against coxsackie virus A6 (CVA6), coxsackie virus A10 (CVA10) among 15 cases and six healthy children in the kindergarten. Meanwhile, some children were carried out with routine blood, fungal microscopic and microelement tests. Indoor environment examinations had been done for all classes. RESULTS: A total of 20 cases were identified in Kindergarten H. Seventy-five percent (15/20) cases occurred in Primary Class #2. Fifty-five percent of the cases (11/20) had suffered from HFMD within two months. The median time between onychomadesis and HFMD was 45 days (ranging from 31 to 58 days). A retrospective cohort study in Primary Class #2 showed the attack rate was 90.0% among 10 children who suffered from HFMD in the past two months compared to 30.0% among 20 children who didn't (Rate Ratio [RR] =3.0, 95% Confidence Interval [CI] =1.5-6.0). The positive rates of neutralizing antibodies were 66.7% for CVA6 and 26.7% for CVA10 in tested cases. The result of routine blood, fungal microscopic, microelements tests were normal in cases. The indicators of environment were within the normal range. CONCLUSION: The results of this study suggested that the outbreak of onychomadesis in Hubei province was probably associated with HFMD epidemic within two months.


Assuntos
Doença de Mão, Pé e Boca/epidemiologia , Doenças da Unha/epidemiologia , Doenças da Unha/etiologia , Anticorpos Neutralizantes , Anticorpos Antivirais , Pré-Escolar , China/epidemiologia , Surtos de Doenças , Enterovirus Humano A/imunologia , Feminino , Doença de Mão, Pé e Boca/etiologia , Humanos , Incidência , Masculino , Estudos Retrospectivos , Instituições Acadêmicas
16.
J Prosthet Dent ; 120(4): 609-616, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29724549

RESUMO

STATEMENT OF PROBLEM: The use of composite resin to restore teeth has increased substantially during the last decades. However, secondary caries and the fracture of restorations are the leading reasons for clinical restoration failure. Mechanically strong composite resins with caries-inhibition capabilities are needed. Although antibacterial dimethacrylate quaternary ammonium monomers have been synthesized, composite resin containing dimethacrylate quaternary ammonium monomers and glass fillers has rarely been reported. PURPOSE: The purpose of this in vitro study was to evaluate the possibility of the clinical use of an experimental composite resin containing urethane dimethacrylate quaternary ammonium compound (UDMQA-12) by investigating its antibacterial activity, cytotoxicity, flexural strength, and flexural modulus. MATERIAL AND METHODS: Antibacterial activity against Streptococcus mutans was investigated by means of direct contact test. The antibacterial activity of specimens after water immersion and saliva treatment was also tested. These were compared with a commercially available composite resin, Z250, and a glass ionomer cement, Fuji VII. Effects of the eluent from the experimental composite resin on the metabolic activity of human dental pulp cells were quantified. Disks of 1 mm in thickness and 15 mm in diameter were used in the antibacterial and cytotoxic tests. Flexural strength and flexural modulus were measured with a 3-point bend test with bars of 2×2×25 mm. Three commercially available composite resins (Filtek Z250, G-aenial Anterior, and G-aenial Posterior) were used as controls in the flexural test. RESULTS: Bacterial growth was inhibited on the experimental composite resin. After water immersion or saliva treatment, the experimental composite resin showed significant antibacterial effect compared with the conventional composite resin (P<.05). No significant difference was found in cytotoxicity between the experimental composite resin and the conventional composite resin (P>.05), and a significantly higher cytotoxicity was shown by glass ionomer cement compared with the experimental composite resin and the conventional composite resin (P<.05). The conventional composite resin had the highest flexural strength and flexural modulus (P<.05), followed by the experimental composite resin, then G-ænial Posterior and G-ænial Anterior. CONCLUSIONS: The antibacterial experimental composite resin was biocompatible and had mechanical properties similar to those of some commercially available composite resins. It might, therefore, be useful in preventing the occurrence of secondary caries.


Assuntos
Antibacterianos/farmacologia , Resinas Compostas/farmacologia , Citotoxinas/farmacologia , Compostos de Amônio Quaternário/farmacologia , Antibacterianos/química , Resinas Compostas/química , Citotoxinas/química , Polpa Dentária/citologia , Polpa Dentária/efeitos dos fármacos , Resistência à Flexão , Humanos , Técnicas In Vitro , Metacrilatos/química , Metacrilatos/farmacologia , Testes de Sensibilidade Microbiana , Poliuretanos/química , Poliuretanos/farmacologia , Compostos de Amônio Quaternário/química , Streptococcus mutans/efeitos dos fármacos
17.
Cell Tissue Res ; 364(2): 309-18, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26646542

RESUMO

Long noncoding RNAs (lncRNAs) have recently emerged as an important class of regulatory molecules in diverse biological processes, although lncRNA involvement in the odontoblast-like differentiation of human dental pulp cells (hDPCs) is poorly understood. We investigate the expression of lncRNAs in this differentiation and explore their underlying role and the involved mechanism. Integrated comparative lncRNA microarray profiling was used to examine lncRNA expression during this differentiation. The differential expression of lncRNAs was validated by quantitative real-time reverse transcription plus the polymerase chain reaction. Differential lncRNA overexpression was performed with an adenoviral vector and the role and mechanism was then investigated in odontoblast-like differentiation. We identified 139 differentially expressed lncRNAs during this differentiation. Among them, five lncRNAs differentially expressed in microarray analysis were validated. Notably, lncRNA DANCR expression was significantly downregulated during hDPC differentiation to odontoblast-like cells in a time-dependent manner. Moreover, lncRNA DANCR overexpression blocked mineralized nodule formation and the expression of DSPP and DMP-1 in hDPCs after 14 days of odontogenic induction. Importantly, the upregulation of DANCR significantly decreased the expression levels of p-GSK-3ß and ß-catenin expression indicating that lncRNA DANCR can inhibit the activation of the Wnt/ß-catenin signal pathway during the odontoblast-like differentiation of hDPCs. Thus, the modulation of Wnt/ß-catenin signaling by lncRNA DANCR represents a potential therapeutic option for reparative dentin formation and regenerative endodontics.


Assuntos
Diferenciação Celular/genética , Polpa Dentária/citologia , Odontoblastos/citologia , Odontogênese/genética , RNA Longo não Codificante/genética , Proteínas Wnt/antagonistas & inibidores , Via de Sinalização Wnt/genética , beta Catenina/antagonistas & inibidores , Células Cultivadas , Dentina/metabolismo , Glicogênio Sintase Quinase 3 beta/biossíntese , Humanos , beta Catenina/biossíntese
18.
Analyst ; 141(15): 4573-7, 2016 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-27346241

RESUMO

Using Zn(2+)-BPMP or Cu(2+)-BPMP as a receptor and o-mercaptophenol as an indicator, potentiometric sensing of aqueous phosphate by competition assays was achieved. With attractive features of portability, low cost and resistance to interference from turbidity and color, this sensor was successfully used for phosphate detection in biological and water samples.


Assuntos
Águas Minerais/análise , Fosfatos/análise , Potenciometria , Saliva/química , Urina/química , Eletrodos , Humanos , Fenóis , Polímeros
19.
Eur J Oral Sci ; 124(4): 334-42, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27334431

RESUMO

A specific and sensitive detection system was designed to detect Porphyromonas gingivalis, a major periodontal pathogen, in mixed bacterial fluids. This new detection system was based on the use of fluorescent and magnetic encoding nanospheres that were conjugated with monoclonal antibodies specific to P. gingivalis, thus enabling rapid detection of the target bacterium. This strategy simplifies the detection process and improves the sensitivity compared with conventional methods, with a detection limit of approximately 10 colony-forming units (CFU) ml(-1) . This new method shows strong anti-interference ability and excellent selectivity and specificity to detect P. gingivalis in mixed solutions.


Assuntos
Nanosferas , Porphyromonas gingivalis/isolamento & purificação , Corantes , Magnetismo , Periodontite , Sensibilidade e Especificidade
20.
J Mater Sci Mater Med ; 27(4): 81, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26936367

RESUMO

The modification of cardiovascular stent surface for a better micro-environment has gradually changed to multi-molecule, multi-functional designation. In this study, heparin (Hep) and type IV collagen (IVCol) were used as the functional molecule to construct a bifunctional micro-environment of anticoagulation and promoting endothelialization on titanium (Ti). The surface characterization results (AFM, Alcian Blue 8GX Staining and fluorescence staining of IVCol) indicated that the bio-layer of Hep and IVCol were successfully fabricated on the Ti surface through electrostatic self-assembly. The APTT and platelet adhesion test demonstrated that the bionic layer possessed better blood compatibility compared with Ti surface. The adhesion, proliferation, migration and apoptosis tests of endothelial cells proved that the Hep/IVCol layer was able to enhance the endothelialization of the Ti surface. The in vivo animal implantation results manifested that the bionic surface could encourage new endothelialization. This work provides an important reference for the construction of multifunction micro-environment on the cardiovascular scaffold surface.


Assuntos
Colágeno Tipo IV/fisiologia , Heparina/química , Titânio/química , Animais , Materiais Biocompatíveis , Colágeno Tipo IV/química , Cães , Células Endoteliais/fisiologia , Artéria Femoral , Heparina/fisiologia , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Propriedades de Superfície
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