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1.
J Nanobiotechnology ; 22(1): 321, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38849841

RESUMEN

Acute lung injury (ALI) is a life threatening disease in critically ill patients, and characterized by excessive reactive oxygen species (ROS) and inflammatory factors levels in the lung. Multiple evidences suggest that nanozyme with diversified catalytic capabilities plays a vital role in this fatal lung injury. At present, we developed a novel class of polydopamine (PDA) coated cerium dioxide (CeO2) nanozyme (Ce@P) that acts as the potent ROS scavenger for scavenging intracellular ROS and suppressing inflammatory responses against ALI. Herein, we aimed to identify that Ce@P combining with NIR irradiation could further strengthen its ROS scavenging capacity. Specifically, NIR triggered Ce@P exhibited the most potent antioxidant and anti-inflammatory behaviors in lipopolysaccharide (LPS) induced macrophages through decreasing the intracellular ROS levels, down-regulating the levels of TNF-α, IL-1ß and IL-6, up-regulating the level of antioxidant cytokine (SOD-2), inducing M2 directional polarization (CD206 up-regulation), and increasing the expression level of HSP70. Besides, we performed intravenous (IV) injection of Ce@P in LPS induced ALI rat model, and found that it significantly accumulated in the lung tissue for 6 h after injection. It was also observed that Ce@P + NIR presented the superior behaviors of decreasing lung inflammation, alleviating diffuse alveolar damage, as well as promoting lung tissue repair. All in all, it has developed the strategy of using Ce@P combining with NIR irradiation for the synergistic enhanced treatment of ALI, which can serve as a promising therapeutic strategy for the clinical treatment of ROS derived diseases as well.


Asunto(s)
Lesión Pulmonar Aguda , Cerio , Indoles , Polímeros , Especies Reactivas de Oxígeno , Cerio/química , Cerio/farmacología , Animales , Lesión Pulmonar Aguda/tratamiento farmacológico , Polímeros/química , Polímeros/farmacología , Indoles/química , Indoles/farmacología , Especies Reactivas de Oxígeno/metabolismo , Ratas , Ratones , Masculino , Células RAW 264.7 , Pulmón/efectos de los fármacos , Pulmón/patología , Antioxidantes/farmacología , Antioxidantes/química , Ratas Sprague-Dawley , Lipopolisacáridos/farmacología , Antiinflamatorios/farmacología , Antiinflamatorios/química , Rayos Infrarrojos , Depuradores de Radicales Libres/farmacología , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/uso terapéutico , Nanopartículas/química , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Citocinas/metabolismo
2.
Luminescence ; 39(5): e4778, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38772865

RESUMEN

To establish a new method for detecting crystal violet (CV), a harmful dye, herein, a genre of novel biomass carbon dots (CDs) was synthesized via a microwave method and employed as a fluorescent probe, in which water spinach and polyethylene glycol (PEG) performed as raw materials. Based on the inner filter effect (IFE) between the luminescent CDs and CV, the blue emission of this probe at 430 nm could be quenched by CV. Hence, a new strategy was proposed to selectively determine CV in aquaculture ambient. Moreover, under the optimal experiment conditions, this method showed a good linearity between the concentration of CV (c) and fluorescence quenching rate (ΔF/F0) in the concentration range of 4-200 µmol/L with the corresponding correlation coefficient (r) and the detection limit of 0.997 and 710 nmol/L, respectively. With advantages of environmental protectivity, sensitivity, affordability, and user-friendliness, the facilely fabricated CDs could be successfully applied in detecting CV in aquaculture samples, providing a technical foundation for monitoring the pollution of CV and ensuring the quality and safety of aquatic products.


Asunto(s)
Biomasa , Carbono , Colorantes Fluorescentes , Violeta de Genciana , Microondas , Puntos Cuánticos , Violeta de Genciana/química , Carbono/química , Puntos Cuánticos/química , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Espectrometría de Fluorescencia , Fluorescencia , Polietilenglicoles/química
3.
BMC Infect Dis ; 23(1): 144, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36890462

RESUMEN

BACKGROUND: To understand the factors influencing clinical outcomes of severe hand, foot, and mouth diseases (HFMD), and to provide scientific evidence for reducing the mortality risk of severe HFMD. METHODS: From 2014 to 2018, children diagnosed with severe HFMD cases in Guangxi, China, were enrolled in this hospital-based study. The epidemiological data obtained through face-to-face interviews with the parents and guardians. Univariate and multivariate logistics regression models were used to analyze the factors influencing the clinical outcomes of severe HFMD. The impact of the EV-A71 vaccination on inpatient mortality was analyzed by a comparison approach. RESULTS: A total of 1565 severe HFMD cases were enrolled in this survey, including 1474 (94.19%) survival cases and 91 (5.81%) death cases. The multivariate logistic analysis demonstrated that HFMD history of playmates in the last three months, first visit to the village hospital, time from the first visit to admission less than two days, no correct diagnosis for HFMD at the first visit, and having no rash symptoms were the independent risk factors for severe HFMD cases (all p < 0.05). While EV-A71 vaccination was a protective factor (p < 0.05). The EV-A71 vaccination group versus the non-vaccination group showed 2.23% of death in the vaccination group and 7.24% of death in the non-vaccination group. The EV-A71 vaccination protected 70.80% of the death of severe HFMD cases, with an effective index of 4.79. CONCLUSIONS: The mortality risk of severe HFMD in Guangxi was related to playmates had HFMD history in last 3 months, hospital grade, EV-A71 vaccination, patients visit hospital previously, and rash symptom. EV-A71 vaccination can significantly reduce mortality among severe HFMD. The findings are of great significance for the effective prevention and control of HFMD in Guangxi, southern China.


Asunto(s)
Enterovirus Humano A , Enterovirus , Exantema , Enfermedad de Boca, Mano y Pie , Enfermedades de la Boca , Niño , Humanos , Lactante , Enfermedad de Boca, Mano y Pie/epidemiología , China/epidemiología , Hospitales
4.
World J Surg Oncol ; 20(1): 112, 2022 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-35387653

RESUMEN

OBJECTIVE: The objective of this research was to investigate the risk factors of cement leakage in patients with metastatic spine tumors following percutaneous vertebroplasty (PVP). METHODS: Sixty-four patients with 113 vertebrae were retrospectively reviewed. Various clinical indexes, including age, sex, body mass index (BMI), smoking history, drinking history, chemotherapy history, radiotherapy history, primary cancer, location, other metastases, collapse, posterior wall defects, the laterality of injection, and the injected cement volume were analyzed as potential risk factors. Multivariate analyses were conducted to identify the independent risk factors. RESULTS: The cement leakage was found 64 in 113 treated vertebrae (56.63%), in which the incidence of each type was shown as below: spinal canal leakage 18 (15.93%), intravascular leakage around the vertebrae 11 (9.73%), and intradiscal and paravertebral leakage 35 (30.97%). Tomita classification (P = 0.019) and posterior wall destruction (P = 0.001) were considered strong risk factors for predicting cement leakage in general. The multivariate logistic analysis showed that defects of the posterior wall (P = 0.001) and injected volume (P = 0.038) were independently related to the presence of spinal canal leakage. The postoperative visual analog scale (VAS) and activities of daily living (ADL) scores showed significant differences compared with the pre-operative parameters (P < 0.05). No significant differences were found in every follow-up time between the leakage group and the non-leakage group for pain management and improvement of activities in daily life. CONCLUSION: In our study, Tomita classification and the destruction of the posterior wall were independent risk factors for leakage in general. The defects of the posterior wall and injected volume were independently related to the presence of spinal canal leakage. The PVP procedure can be an effective way to manage the pain.


Asunto(s)
Fracturas de la Columna Vertebral , Neoplasias de la Columna Vertebral , Vertebroplastia , Actividades Cotidianas , Cementos para Huesos/efectos adversos , Humanos , Estudios Retrospectivos , Factores de Riesgo , Fracturas de la Columna Vertebral/cirugía , Neoplasias de la Columna Vertebral/secundario , Resultado del Tratamiento , Vertebroplastia/efectos adversos , Vertebroplastia/métodos
5.
Appl Environ Microbiol ; 87(23): e0138921, 2021 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-34550763

RESUMEN

Poly-3-hydroxybutyrate (PHB) is an environmentally friendly polymer and can be produced in Escherichia coli cells after overexpression of the heterologous gene cluster phaCAB. The biosynthesis of the outer membrane (OM) consumes many nutrients and influences cell morphology. Here, we engineered the OM by disrupting all gene clusters relevant to the polysaccharide portion of lipopolysaccharide (LPS), colanic acid (CA), flagella, and/or fimbria in E. coli W3110. All these disruptions benefited PHB production. Especially, disrupting all these OM components increased the PHB content to 83.0 wt% (PHB content percentage of dry cell weight), while the wild-type control produced only 1.5 wt% PHB. The increase was mainly due to the LPS truncation to Kdo2 (3-deoxy-d-manno-octulosonic acid)-lipid A, which resulted in 82.0 wt% PHB with a 25-fold larger cell volume, and disrupting CA resulted in 57.8 wt% PHB. In addition, disrupting LPS facilitated advantageous fermentation features, including 69.1% less acetate, a 550% higher percentage of autoaggregated cells among the total culture cells, 69.1% less biofilm, and a higher broken cell ratio. Further detailed mechanism investigations showed that disrupting LPS caused global changes in envelope and cellular metabolism: (i) a sharp decrease in flagella, fimbria, and secretions; (ii) more elastic cells; (iii) much greater carbon flux toward acetyl coenzyme A (acetyl-CoA) and supply of cofactors, including NADP, NAD, and ATP; and (iv) a decrease in by-product acids but increase in γ-aminobutyric acid by activating σE factor. Disrupting CA, flagella, and fimbria also improved the levels of acetyl-CoA and cofactors. The results indicate that engineering the OM is an effective strategy to enhance PHB production and highlight the applicability of OM engineering to increase microbial cell factory performance. IMPORTANCE Understanding the detailed influence of the OM on the cell envelope and cellular metabolism is important for optimizing the E. coli cell factory and many other microorganisms. This study revealed the applicability of remodeling the OM to enhance PHB accumulation as representative inclusion bodies. The results generated in this study give essential information for producing other inclusion bodies or chemicals which need more acetyl-CoA and cofactors but less by-product acids. This study is promising to provide new ideas for the improvement of microbial cell factories.


Asunto(s)
Membrana Externa Bacteriana , Escherichia coli , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo , Acetilcoenzima A , Escherichia coli/genética , Lipopolisacáridos , Microorganismos Modificados Genéticamente
6.
BMC Med Educ ; 21(1): 551, 2021 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-34715870

RESUMEN

BACKGROUND: The shortage of dentists is one of the various medical-resource problems found around the world. More and more countries are improving the provision of oral services by training dental therapists and hygienists. In China, they are called assistant dentists, and they supplement dental services, but thus far, no research has been conducted on the competence of this group. OBJECTIVE: The purpose of this study was to establish a competency model for Chinese assistant dentists. This model can provide a more scientific basis for the education, training, and evaluation of these professionals, as well as provide a reference for the capacity of dental therapists in various countries. METHODS: We established a system of competency characteristics using theoretical analysis and focus group discussions, after which we established an initial competency model by consulting a Delphi panel of 29 experts. Finally, we collected data from 1389 assistant dentists from 14 provinces in China, and the reliability and validity of the model were confirmed by factor analysis of this data. RESULTS: After three rounds of Delphi panels, the competency model came to include seven ability levels and 50 indicators. In exploratory-factor analysis, three indicators were eliminated, and the questionnaire could explain 68.41 % of total variance. In confirmatory-factor analysis, the established model and data fit well (goodness-of-fit index [GFI] = 0.914, root mean square error of approximation [RMSEA] = 0.047). The results showed that the entire model has good reliability and validity. CONCLUSIONS: Our competency model for dental assistants in China includes seven elements. This is consistent with the current health situation in China, and it has distinct Chinese characteristics. Some of our findings, like those reported in other countries with dental therapists, offer ideas for other developing countries.


Asunto(s)
Odontólogos , China , Análisis Factorial , Humanos , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
7.
Molecules ; 26(10)2021 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-34068926

RESUMEN

Icaritin is a promising anti-hepatoma drug that is currently being tested in a phase-III clinical trial. A novel combination of amorphization and nanonization was used to enhance the oral bioavailability of icaritin. Amorphous icaritin nanoparticles (AINs) were prepared by a reactive precipitation technique (RPT). Fourier transform infrared spectrometry was used to investigate the mechanism underlying the formation of amorphous nanoparticles. AINs were characterized via scanning electron microscopy, X-ray powder diffraction, and differential scanning calorimetry. Our prepared AINs were also evaluated for their dissolution rates in vitro and oral bioavailability. The resultant nanosized AINs (64 nm) were amorphous and exhibited a higher dissolution rate than that derived from a previous oil-suspension formulation. Fourier transform infrared spectroscopy (FTIR) revealed that the C=O groups from the hydrophilic chain of polymers and the OH groups from icaritin formed hydrogen bonds that inhibited AIN crystallization and aggregation. Furthermore, an oral administration assay in beagle dogs showed that Cmax and AUClast of the dried AINs formulation were 3.3-fold and 4.5-fold higher than those of the oil-suspension preparation (p < 0.01), respectively. Our results demonstrate that the preparation of amorphous drug nanoparticles via our RPT may be a promising technique for improving the oral bioavailability of poorly water-soluble drugs.


Asunto(s)
Precipitación Química , Flavonoides/síntesis química , Nanopartículas/química , Animales , Perros , Epimedium/anatomía & histología , Epimedium/química , Flavonoides/sangre , Flavonoides/química , Flavonoides/farmacocinética , Masculino , Nanopartículas/ultraestructura , Polímeros/química , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
8.
Molecules ; 25(14)2020 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-32698371

RESUMEN

Glucosinolates (GLs) are of great interest for their potential as antioxidant and anticancer compounds. In this study, macroporous crosslinked copolymer adsorbents of poly (glycidyl methacrylate) (PGMA) and its amine (ethylenediamine, diethylamine, triethylamine)-modified derivatives were prepared and used to purify the GLS glucoerucin in a crude extract obtained from a cruciferous plant. These four adsorbents were evaluated by comparing their adsorption/desorption and decolorization performance for the purification of glucoerucin from crude plant extracts. According to the results, the strongly basic triethylamine modified PGMA (PGMA-III) adsorbent showed the best adsorption and desorption capacity of glucoerucin, and its adsorption data was a good fit to the Freundlich isotherm model and pseudo-second-order kinetics; the PGMA adsorbent gave the optimum decolorization performance. Furthermore, dynamic adsorption/desorption experiments were carried out to optimize the purification process. Two glass columns were serially connected and respectively wet-packed with PGMA and PGMA-III adsorbents so that glucoerucin could be decolorized and isolated from crude extracts in one process. Compared with KCl solution, aqueous ammonia was a preferable desorption solvent for the purification of glucoerucin and overcame the challenges of desalination efficiency, residual methanol and high operation costs. The results showed that after desorption with 10% aqueous ammonia, the purity of isolated glucoerucin was 74.39% with a recovery of 80.63%; after decolorization with PGMA adsorbent, the appearance of glucoerucin was improved and the purity increased by 11.30%. The process of using serially connected glass columns, wet-packed with PGMA and PGMA-III, may provide a simple, low-cost, and efficient method for the purification of GLs from cruciferous plants.


Asunto(s)
Aminas/química , Brassicaceae/química , Glucosinolatos/aislamiento & purificación , Ácidos Polimetacrílicos/química , Adsorción , Glucosa/análogos & derivados , Glucosa/química , Glucosa/aislamiento & purificación , Glucosinolatos/química , Concentración de Iones de Hidrógeno , Imidoésteres/química , Imidoésteres/aislamiento & purificación , Cinética , Ácidos Polimetacrílicos/síntesis química , Soluciones , Solventes/química , Espectroscopía Infrarroja por Transformada de Fourier
10.
Water Sci Technol ; 2017(1): 300-309, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29698244

RESUMEN

This study prepared a carboxylate-functionalized sugarcane bagasse (CF-SCB) from sugarcane bagasse (SCB) via a simple and low-toxicity chemical modification to enhance its capacity for adsorbing methylene blue (MB) from aqueous solutions. The success of chemical modification was confirmed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), the pore area and porosity, and zeta potential measurement analysis. The adsorption capacity of CF-SCB was investigated at different pHs, ionic strengths, temperatures, contact times and initial dye concentrations. Equilibrium data were best described by the Langmuir isotherm model, and the maximum monolayer adsorption capacity of CF-SCB (296.74 mg g-1) was greatly improved compared with SCB (77.16 mg g-1) at 30 °C. The thermodynamic study indicated that MB adsorption onto CF-SCB was a spontaneous, endothermic and entropy increased process. Adsorption kinetics followed a pseudo-second-order mode, and the adsorption mechanism was based on electrostatic interactions. The reusability study showed that CF-SCB had reasonably good reuse potential. All the results suggested that CF-SCB has high potential to be used as an effective and renewable adsorbent for MB removal from wastewater.


Asunto(s)
Celulosa/química , Azul de Metileno/química , Saccharum/química , Contaminantes Químicos del Agua/química , Adsorción , Cinética , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , Tiazinas , Aguas Residuales , Purificación del Agua
11.
Biotechnol Appl Biochem ; 63(2): 214-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-25676477

RESUMEN

A novel multi-enzyme co-immobilized nanoparticle was prepared by the bis-aryl hydrazone conjugation strategy for enhancing the overall reaction efficiency and specificity. It can be seen that the molar substitution ratios of succinimidyl 6-hydrazinonicotinamid acetone hydrazone or succinimidyl 4-formylbenzoate to glucose oxidase (GOX) or horseradish peroxidase (HRP) increased with the concentration of the linking reagents. The amount of the immobilized conjugates on the support was measured to be 22.8 ± 1.6 mg/g-particle, and it meant that more than 90% of the GOX-HRP conjugates were successfully attached onto the polystyrene (PS) nanoparticles. Moreover, the immobilized bi-enzymes conjugate on the PS nanoparticles increased about 1.6-fold compared with that of free enzymes.


Asunto(s)
Enzimas Inmovilizadas/química , Glucosa Oxidasa/química , Peroxidasa de Rábano Silvestre/química , Hidrazonas/química , Nanopartículas/química , Poliestirenos/química , Enzimas Inmovilizadas/metabolismo , Glucosa Oxidasa/metabolismo , Peroxidasa de Rábano Silvestre/metabolismo , Hidrazonas/metabolismo , Estructura Molecular , Nanopartículas/metabolismo , Tamaño de la Partícula , Poliestirenos/metabolismo , Propiedades de Superficie
13.
J Am Chem Soc ; 136(39): 13558-61, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-25233109

RESUMEN

Noble metals, especially gold, have been widely used in plasmon resonance applications. Although silver has a larger optical cross section and lower cost than gold, it has attracted much less attention because of its easy corrosion, thereby degrading plasmonic signals and limiting its applications. To circumvent this problem, we report the facile synthesis of superstable AgCu@graphene (ACG) nanoparticles (NPs). The growth of several layers of graphene onto the surface of AgCu alloy NPs effectively protects the Ag surface from contamination, even in the presence of hydrogen peroxide, hydrogen sulfide, and nitric acid. The ACG NPs have been utilized to enhance the unique Raman signals from the graphitic shell, making ACG an ideal candidate for cell labeling, rapid Raman imaging, and SERS detection. ACG is further functionalized with alkyne-polyethylene glycol, which has strong Raman vibrations in the Raman-silent region of the cell, leading to more accurate colocalization inside cells. In sum, this work provides a simple approach to fabricate corrosion-resistant, water-soluble, and graphene-protected AgCu NPs having a strong surface plasmon resonance effect suitable for sensing and imaging.


Asunto(s)
Alquinos/química , Grafito/química , Nanopartículas/química , Plata/química , Cobre/química , Humanos , Células MCF-7 , Tamaño de la Partícula , Polietilenglicoles/química , Espectrometría Raman , Propiedades de Superficie
14.
J Oral Pathol Med ; 43(9): 696-703, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24931443

RESUMEN

BACKGROUND: Highly active antiretroviral therapy (HAART) as an effective therapy for immune reconstruction among patients with HIV/AIDS might have influence on oral Candida status. We investigated oral Candida carriage, distribution, and antifungal susceptibility dynamically during the first year of HAART among adult HIV-infected patients in Guangxi, China. METHODS: Forty-five adult HIV-infected patients who received their first year HAART in the AIDS clinic of the Guangxi Center for Disease Control (CDC) and 31 healthy individuals were recruited. Clinical information and oral examinations were obtained. Oral rinses taken from patients at baseline, 3, 6, 12 months during HAART, respectively, were cultured, and Candida species were identified following standard microbiological techniques. In vitro antifungal susceptibilities were tested by the broth microdilution method. RESULTS: The oral Candida load decreased gradually in the 45 patients with HIV/AIDS during the first year of HAART (P < 0.050). Among 176 Candida isolates, Candida albicans (114/176) was the predominant species, and Candida parapsilosis (23/62) was the most common non-albicans species. We found the frequency of resistance to fluconazole and itraconazole of Candida isolated from our samples increased (P < 0.05) after 12 months of HAART. In addition, the frequency of C. albicans isolates resistant to fluconazole and itraconazole was on the rise (P < 0.05). CONCLUSIONS: The Candida load decreased with increased CD4(+) T cell counts, and C. albicans was still the prevailing species. Further, a trend toward more frequent in vitro resistance to fluconazole and itraconazole was observed. Our results provide reference for treatment and prevention of oral candidiasis among this population.


Asunto(s)
Antifúngicos/farmacología , Terapia Antirretroviral Altamente Activa , Candida/clasificación , Farmacorresistencia Fúngica/fisiología , Infecciones por VIH/tratamiento farmacológico , Boca/microbiología , Infecciones Oportunistas Relacionadas con el SIDA/prevención & control , Adulto , Anciano , Recuento de Linfocito CD4 , Candida/efectos de los fármacos , Candida/aislamiento & purificación , Candida albicans/efectos de los fármacos , Candida albicans/aislamiento & purificación , Candidiasis Bucal/prevención & control , Estudios de Casos y Controles , Recuento de Colonia Microbiana , Femenino , Fluconazol/farmacología , Estudios de Seguimiento , Humanos , Itraconazol/farmacología , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Estudios Prospectivos , Saliva/microbiología
15.
Appl Microbiol Biotechnol ; 98(20): 8685-95, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25056289

RESUMEN

Dental caries and periodontitis are common bacterial mouth infections. As a potentially attractive substitute for conventional antibiotics, antimicrobial peptides have been widely tested and used for controlling bacterial infections. In this study, we tested the efficacy of the peptides from the skin secretions of Rana chensinensis for killing several major cariogenic and periodontic pathogens as well as Candida albicans. L-K6, a temporin-1CEb analog, exhibited high antimicrobial activity against the tested oral pathogens and was able to inhibit Streptococcus mutans biofilm formation and reduce 1-day-old S. mutans biofilms with a minimum biofilm inhibitory concentration and reducing concentration of 3.13 and 6.25 µM, respectively. The results of confocal laser scanning microscopy demonstrated that the peptide significantly reduced cell viability within oral biofilms. Furthermore, as little as 5 µM L-K6 significantly inhibited lipopolysaccharide (LPS)- and interleukin-1ß-induced productions of interleukin-8 and tumor necrosis factor-α from THP-1 monocytic cells. This anti-inflammatory activity is associated with the binding of L-K6 to LPS and neutralizing LPS-induced proinflammatory responses in THP-1 cells, as well as dissociating LPS aggregates. Our results suggest that L-K6 may have potential clinical applications in treating dental caries by killing S. mutans within dental plaque and acting as anti-inflammatory agents in infected tissues.


Asunto(s)
Antiinflamatorios/farmacología , Péptidos Catiónicos Antimicrobianos/farmacología , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Streptococcus mutans/efectos de los fármacos , Streptococcus mutans/fisiología , Animales , Antiinflamatorios/aislamiento & purificación , Péptidos Catiónicos Antimicrobianos/aislamiento & purificación , Candida albicans/efectos de los fármacos , Candida albicans/crecimiento & desarrollo , Candida albicans/fisiología , Línea Celular , Interleucina-8/antagonistas & inhibidores , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Monocitos/efectos de los fármacos , Ranidae , Streptococcus mutans/crecimiento & desarrollo , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
16.
ACS Sens ; 9(4): 1866-1876, 2024 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-38499997

RESUMEN

Electromagnetic sensors with flexible antennas as sensing elements have attracted increasing attention in noninvasive continuous glucose monitoring for diabetic patients. The significant radiation performance loss of flexible antennas during mechanical deformation impairs the reliability of glucose monitoring. Here, we present flexible ultrawideband monopole antennas composed of Ti3C2 MXene and cellulose nanofibril (CNF) composite films for continuous glucose monitoring. The flexible MXene/CNF antenna with 20% CNF content can obtain a gain of up to 3.33 dBi and a radiation efficiency of up to 65.40% at a frequency range from 2.3 to 6.0 GHz. Compared with the pure MXene antenna, this antenna offers a comparable radiation performance and a lower performance loss in mechanical bending deformation. Moreover, the MXene/CNF antenna shows a stable response to fetal bovine serum/glucose, with a correlation of >0.9 at the reference glucose levels, and responds sensitively to the variations in blood glucose levels during human trials. The proposed strategy enhancing the mechanical robustness of MXene-based flexible antennas makes metallic two-dimensional nanomaterials more promising in wearable electromagnetic sensors.


Asunto(s)
Glucemia , Celulosa , Titanio , Celulosa/química , Titanio/química , Humanos , Glucemia/análisis , Nanocompuestos/química , Técnicas Biosensibles/métodos , Dispositivos Electrónicos Vestibles , Animales , Nanofibras/química , Glucosa/análisis
17.
Environ Sci Pollut Res Int ; 31(22): 33047-33057, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38668948

RESUMEN

During the COVID-19 pandemic, a substantial quantity of disposable face masks was discarded, consisting of three layers of nonwoven fabric. However, their improper disposal led to the release of microplastics (MPs) and nanoplastics (NPs) when they ended up in aquatic environments. To analyze the release kinetics and size characteristics of these masks, release experiments were performed on commercially available disposable masks over a period of 7 days and micro- and nanoplastic releases were detected using fiber counting and nanoparticle tracking analysis. The study's findings revealed that there was no significant difference (p > 0.05) in the quantity of MPs released among the layers of the masks. However, the quantity of NPs released from the middle layer of the mask was 25.9 ± 1.3 × 108 to 81.3 ± 5.3 × 108 particles/piece, significantly higher than the inner and outer layers (p < 0.05). The release process of micro/nanoplastics (M/NPs) from each layer of the mask followed the Elovich equation and the power function equation, indicating that the release was divided into two stages. MPs in the range of 1-500 µm and NPs in the range of 100-300 nm dominated the release from each layer of the mask, accounting for an average of 93.81% and 67.52%, respectively. Based on these findings, recommendations are proposed to reduce the release of M/NPs from masks during subsequent use.


Asunto(s)
COVID-19 , Máscaras , Microplásticos , Plásticos , Microplásticos/análisis , COVID-19/prevención & control , Humanos , Contaminantes Químicos del Agua/análisis , SARS-CoV-2 , Nanopartículas/química
18.
ACS Appl Mater Interfaces ; 16(15): 18551-18563, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38564314

RESUMEN

High levels of reactive oxygen species (ROS) are known to play a critical role in the secondary cascade of spinal cord injury (SCI). The scavenging of ROS has emerged as a promising approach for alleviating acute SCI. Moreover, identifying the precise location of the SCI site remains challenging. Enhancing the visualization of the spinal cord and improving the ability to distinguish the lesion site are crucial for accurate and safe treatment. Therefore, there is an urgent clinical need to develop a biomaterial that integrates diagnosis and treatment for SCI. Herein, ultra-small-sized gold nanodots (AuNDs) were designed for dual-mode imaging-guided precision treatment of SCI. The designed AuNDs demonstrate two important functions. First, they effectively scavenge ROS, inhibit oxidative stress, reduce the infiltration of inflammatory cells, and prevent apoptosis. This leads to a significant improvement in SCI repair and promotes a functional recovery after injury. Second, leveraging their excellent dual-mode imaging capabilities, the AuNDs enable rapid and accurate identification of SCI sites. The high contrast observed between the injured and adjacent uninjured areas highlights the tremendous potential of AuNDs for SCI detection. Overall, by integrating ROS scavenging and dual-mode imaging in a single biomaterial, our work on functionalized AuNDs provides a promising strategy for the clinical diagnosis and treatment of SCI.


Asunto(s)
Oro , Traumatismos de la Médula Espinal , Humanos , Especies Reactivas de Oxígeno , Oro/uso terapéutico , Traumatismos de la Médula Espinal/tratamiento farmacológico , Estrés Oxidativo , Materiales Biocompatibles/uso terapéutico
19.
Int J Biol Macromol ; 237: 124177, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36972823

RESUMEN

Persistent bacterial infection caused by biofilms is one of the most serious problems that threatened human health. The development of antibacterial agents remains a challenge to penetrate biofilm and effectively treat the underlying bacterial infection. In the current study, chitosan-based nanogels were developed for encapsulating the Tanshinone IIA (TA) to enhance the antibacterial and anti-biofilm efficacy against Streptococcus mutans (S. mutans). The as-prepared nanogels (TA@CS) displayed excellent encapsulation efficiency (91.41 ± 0.11 %), uniform particle sizes (393.97 ± 13.92 nm), and enhanced positive potential (42.27 ± 1.25 mV). After being coated with CS, the stability of TA under light and other harsh environments was greatly improved. In addition, TA@CS displayed pH responsiveness, allowing it to selectively release more TA in acidic conditions. Furthermore, the positively charged TA@CS were equipped to target negatively charged biofilm surfaces and efficiently penetrate through biofilm barriers, making it promising for remarkable anti-biofilm activity. More importantly, when TA was encapsulated into CS nanogels, the antibacterial activity of TA was enhanced at least 4-fold. Meanwhile, TA@CS inhibited 72 % of biofilm formation at 500 µg/mL. The results demonstrated that the nanogels constituted CS and TA had antibacterial/anti-biofilm properties with synergistic enhanced effects, which will benefit pharmaceutical, food, and other fields.


Asunto(s)
Quitosano , Humanos , Quitosano/química , Nanogeles , Antibacterianos/farmacología , Concentración de Iones de Hidrógeno , Biopelículas
20.
Environ Sci Pollut Res Int ; 30(58): 121702-121712, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37953423

RESUMEN

This study investigated the photodegradation of microplastics (MPs) by α-Fe2O3/g-C3N4. The effects of α-Fe2O3/g-C3N4 on MPs' surface were investigated through various techniques. With the addition of α-Fe2O3/g-C3N4 and under visible light irradiation, cracks and folds were observed on the MP films and particles. Compared to the treatment without photocatalyst addition, the mass loss of MPs increased with irradiation time when α-Fe2O3/g-C3N4 was added. Specifically, polystyrene films and particles in water showed 9.94% and 7.81% increased mass loss, respectively. The degradation of MPs using α-Fe2O3/g-C3N4 demonstrated the behavior consistent with the pseudo-first-order kinetic model. The presence of α-Fe2O3/g-C3N4 led to an increase in surface oxygen-containing functional groups and crystallinity while decreasing the average molecular weight of MPs. After 30 days of irradiation, the characteristic tensile bands of MPs with α-Fe2O3/g-C3N4 significantly increased, and the detection of carboxyl bands indicated the formation of carboxylic acid, ketones, and lactones as degradation products.


Asunto(s)
Polietileno , Poliestirenos , Microplásticos , Plásticos , Ácidos Carboxílicos
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