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1.
Proc Natl Acad Sci U S A ; 118(46)2021 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-34750272

RESUMEN

Artificial photosynthesis in ambient conditions is much less efficient than the solar-to-biomass conversion (SBC) processes in nature. Here, we successfully mimic the NADP-mediated photosynthetic processes in green plants by introducing redox moieties as the electron acceptors in the present conjugated polymeric photocatalyst. The current artificial process substantially promotes the charge carrier separation efficiency and the oxygen reduction efficiency, achieving a photosynthesis rate for converting Earth-abundant water and oxygen in air into hydrogen peroxide as high as 909 µmol⋅g-1⋅h-1 and a solar-to-chemical conversion (SCC) efficiency up to 0.26%. The SCC efficiency is more than two times higher than the average SBC efficiency in nature (0.1%) and the highest value under ambient conditions. This study presents a strategy for efficient SCC in the future.


Asunto(s)
Fotosíntesis/fisiología , Biomasa , Biomimética/métodos , Catálisis , Peróxido de Hidrógeno/química , NADP , Oxidación-Reducción , Oxígeno/química , Procesos Fotoquímicos , Polímeros/química , Energía Solar , Luz Solar , Agua/química
2.
Anal Chem ; 93(26): 9226-9234, 2021 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-34165288

RESUMEN

Herein, a new strategy to increase the sensitivity of a lanthanide metal-organic framework (Ln-MOF) to UO22+ was proposed by using polymeric ligands. By utilizing [Tb(1,3,5-benzenetrisbenzoate)]n (Tb-TBT) MOF as the host, preloaded 2-vinyl terephthalic acid (VTP) was polymerized in situ, which produced a novel fluorescent composite denoted as PVTP⊂Tb-TBT. Benefiting from the coordination of PVTP to the Tb nodes, the polymeric chains performed both as molecular scaffolds that improved the water stability of the framework and as additional antennae that sensitized the photoluminescence of the Tb nodes. More importantly, the detection sensitivity and selectivity of PVTP⊂Tb-TBT to UO22+ were much improved compared to those of Tb-TBT. Detailed characterizations indicated that the incorporation of PVTP efficiently enriched UO22+ in the probe, which promoted the energy dissipation to UO22+. Besides, UO22+ was also supposed to release PVTP from PVTP⊂Tb-TBT and, thus, exposed the open metal sites to water molecules, which interrupted the sensitization effect of PVTP and induced a nonradiative energy dissipation. A limit of detection (LOD) as low as 0.75 nm was recorded by suspending the PVTP⊂Tb-TBT probe in a water sample, far below the limit in drinking water set by the United States Environmental Protection Agency (130 nm). Furthermore, a remotely controlled sampling and an on-site analysis of real water samples were realized by facilely loading PVTP⊂Tb-TBT on thin films (TFs). The LOD for UO22+ was 2.5 nm by using the TFs. This study reports a new strategy for boosting the sensitivity and selectivity of Ln-MOF to monitor UO22+ and expands the application of the strategy to an on-site analysis.


Asunto(s)
Elementos de la Serie de los Lantanoides , Estructuras Metalorgánicas , Ligandos , Polímeros , Radioisótopos
3.
Anal Chem ; 90(5): 3387-3394, 2018 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-29417807

RESUMEN

With regard to regulating a variety of biological events, including molecular recognition, signal transduction, cell adhesion, and immune response, cis-diol biomolecules, such as saccharides and glycoproteins, play vital roles. However, saccharides and glycoproteins in living systems usually exist in very low abundance, along with abundant interfering components. High-efficiency detection of saccharides and glycoproteins is a challenging yet highly impactful area of research. Herein, we reported a novel magnetic microprobe with a benzoboroxole-modified flexible multisite arm (PEG 2000-grafted PAMAM dendrimers; the microprobe was denoted as BFMA-MNP) for high-efficiency saccharides detection. The extraction capacity was significantly improved by ∼2 orders of magnitude, because of the integration of the enhanced hydrophilicity and multivalency effects in benzoboroxoles and the enhanced accessibility of the binding sites within the PEG 2000-grafted PAMAM dendrimers. As a result, the proposed approach possessed several advantages, compared with previous boronic acid-based methods, including ultrahigh sensitivity (limit of detection was <1 ng/mL), wide linear range (ranged from 0.5 µM to 2000 µM), and applicable in physiological pH condition. Furthermore, we established a general BFMA-MNP/glycoproteins/AuNPs sandwich assay to realize the visual glycoprotein qualitative screening for the first time. The unique sandwich assay possessed the dual nature of the magnetic separation by BFMA-MNPs and specific coloration by citrate-coated AuNPs. This visual sandwich assay enabled fast differentiation of the existence of glycoproteins in complicated samples without any advanced instruments. We believe the proposed BFMA-MNP microprobe herein will advance the ideas to detect and identify trace saccharides and glycoproteins in important fields such as glycomics and glycoproteomics.


Asunto(s)
Técnicas Biosensibles/métodos , Carbohidratos/análisis , Dendrímeros/química , Glicoproteínas/análisis , Imanes/química , Polietilenglicoles/química , Animales , Ácidos Borónicos/química , Bovinos , Oro/química , Nanopartículas del Metal/química
4.
Anal Chem ; 88(11): 5841-8, 2016 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-27189112

RESUMEN

A novel solid-phase microextraction (SPME) fiber was prepared by gluing poly(diallyldimethylammonium chloride) (PDDA) assembled graphene oxide (GO)-coated C18 composite particles (C18@GO@PDDA) onto a quartz fiber with polyaniline (PANI). The fiber surface coating was sequentially modified with bioinspired polynorepinephrine, which provided a smooth biointerface and makes the coating suitable for in vivo sampling. The novel custom-made coating was used to extract acidic pharmaceuticals, and high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) was employed for analysis. The custom-made coating exhibited a much higher extraction efficiency than the previously used commercial polydimethylsiloxane (PDMS) and polyacrylate (PA) coatings. The custom-made coating also possessed satisfactory stability (the relative standard deviations (RSDs) ranged from 1.60% to 10.3% for six sampling-desorption cycles), interfiber reproducibility (the RSDs ranged from 2.61% to 11.5%), and resistance to matrix effects. The custom-made fibers were used to monitor the presence of acid pharmaceuticals in dorsal-epaxial muscle of living fish, and satisfactory sensitivities (limits of detection ranged from 0.13 ng/g to 7.56 ng/g) were achieved. The accuracies were verified by the comparison with liquid extraction. Moreover, the novel fibers were successfully used to monitor the presence of acidic pharmaceuticals in living fish, which demonstrated that the custom-made fibers were feasible for possible long-term in vivo continuous pharmaceutical monitoring.


Asunto(s)
Grafito/química , Hidrocarburos/química , Óxidos/química , Preparaciones Farmacéuticas/análisis , Polietilenos/química , Compuestos de Amonio Cuaternario/química , Microextracción en Fase Sólida , Animales , Electrólitos/química , Tilapia
5.
Anal Chem ; 87(20): 10593-9, 2015 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-26403643

RESUMEN

Direct detection of fluoxetine and its metabolite norfluoxetine in living fish brains was realized for the first time by using a novel solid-phase microextraction fiber, which was prepared by mixing the polyelectrolyte in the oligomer of silicone rubber and followed by in-mold heat-curing. The polyelectrolyte was finally encased in microcapsules dispersed in the cured silicone rubber. The fiber exhibited excellent interfiber reproducibility (5.4-7.1%, n = 6), intrafiber reproducibility (3.7-4.6%, n = 6), and matrix effect-resistant capacity. Due to the capacity of simultaneously extracting the neutral and the protonated species of the analytes at physiological pH, the fiber exhibited high extraction efficiencies to fluoxetine and norfluoxetine. Besides, the effect of the salinity on the extraction performance and the competitive sorption between the analytes were also evaluated. Based on the small-sized custom-made fiber, the concentrations of fluoxetine and norfluoxetine in the brains of living fish, which were exposed to waterborne fluoxetine at an environmentally relevant concentration, were determined and found 4.4 to 9.2 and 5.0 to 9.2 times those in the dorsal-epaxial muscle. The fiber can be used to detect various protonated bioactive compounds in living animal tissues.


Asunto(s)
Encéfalo/metabolismo , Fluoxetina/análogos & derivados , Fluoxetina/análisis , Polímeros/química , Elastómeros de Silicona/química , Animales , Cápsulas , Electrólitos/química , Fluoxetina/metabolismo , Tilapia
6.
Anal Chem ; 87(6): 3453-9, 2015 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-25711806

RESUMEN

In this study, electrospun nanofibers were used as solid-phase microextraction (SPME) fiber coatings after substituting the water-soluble sheath of the emulsion electrospun polystyrene (PS)@Plurinic F-127 core-sheath nanofibers with biocompatible and water-stable polydopamine (PDA) and subsequently being appropriately cross-linked with glutaraldehyde (GA) to enhance the strength of the electrospun architecture. The novel custom-made PS@PDA-GA coating was wettable in aqueous solutions and thus exhibited much higher extraction efficiency than the nonsheathed PS nanofiber coating and the thicker polydimethylsiloxane (PDMS) coating. The novel coating also possessed excellent stability (relative standard deviations (RSDs) less than 7.3% for six sampling-desorption cycles), interfiber reproducibility (RSDs less than 14.3%), and antibiofouling ability, which were beneficial for in vivo sampling. The PS@PDA-GA fiber was used to monitor pharmaceuticals in dorsal-epaxial muscle of living fish, and satisfactory sensitivities with the limits of detection in the range of 1.1 (mefenamic acid) to 8.9 (fluoxetine) ng·g(-1) and comparable accuracies to liquid extraction were achieved. In general, this study explored a convenient and effective method to sheath nanofibers for high-efficient in vivo SPME of analytes of interest in semisolid tissues.


Asunto(s)
Biomimética , Peces , Indoles/química , Músculos/química , Nanofibras/química , Preparaciones Farmacéuticas/aislamiento & purificación , Polímeros/química , Microextracción en Fase Sólida/métodos , Animales , Incrustaciones Biológicas , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Preparaciones Farmacéuticas/análisis , Reproducibilidad de los Resultados , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/aislamiento & purificación
7.
Analyst ; 140(13): 4384-7, 2015 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-25988962

RESUMEN

Here we report the successful utilization of the stepwise ligand exchange strategy for the improvement of adsorption ability of a series of bio-MOFs. The fast extraction rate and the different adsorption performances of the three bio-MOF coatings were dominated by their pore structures.


Asunto(s)
Materiales Biocompatibles/química , Microextracción en Fase Sólida/instrumentación , Microextracción en Fase Sólida/métodos , Contaminantes Químicos del Agua/análisis , Adsorción , Monitoreo del Ambiente/instrumentación , Monitoreo del Ambiente/métodos , Factores de Tiempo , Difracción de Rayos X
8.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 36(2): 208-210, 2024 Feb.
Artículo en Zh | MEDLINE | ID: mdl-38442941

RESUMEN

Transradial approach is the classical access for coronary angiography and percutaneous coronary intervention (PCI). With the increase in the number of interventional procedures, some disadvantages of the transradial approach have also been found, it is easy to lead to various complications, such as radial artery occlusion, radial nerve injury, and puncture difficulties after radial artery spasm. Therefore, some experts put forward the approach of distal radial artery approach for interventional therapy, which has the advantages of convenient positioning, easy postoperative hemostasis, less damage to the proximal radial artery and improving patients' comfort. However, there is no special distal radial artery hemostat in clinic, which limits the development of this approach to a certain extent. Therefore, based on the principles of anatomy and physics, cardiovascular physician at Jiading District District Central Hospital in Shanghai designed and invented a distal radial artery hemostatic device, which is convenient for clinical hemostasis of distal radial artery puncture, and obtained the National Utility Model Patent (patent number: ZL 2021 2 2097829.6). The hemostatic device consists of a glove body with a silicone gasket protruding towards the skin on the inner surface and a binding component. The patient's hand is inserted into the glove body, and after being fixed by the restraint component, the silicone gasket can effectively compress the location of the radial artery puncture point, and play a good hemostatic effect with less pressure, avoid the common complications of proximal radial artery hemostatic, and reduce the discomfort of the patient. Has good application value.


Asunto(s)
Hemostáticos , Intervención Coronaria Percutánea , Humanos , Arteria Radial , China , Siliconas
9.
Sci Total Environ ; 906: 167655, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37806576

RESUMEN

Tobacco-specific nitrosamines (TSNAs) are probably carcinogenic disinfection byproducts eliciting health risk concerns. The determination and surveillance of TSNAs in water is still cumbersome due to the lack of advanced sample preparation methods. Herein, we prepared a solid phase microextraction (SPME) fiber coated with the molecularly imprinted polymer (MIP) sheathed mesoporous silica tube (MST) composite material, and developed a highly efficient, selective, and sensitive method for the determination of five TSNAs in water. Benefiting from the TSNAs-specific recognition of MIP and the increased specific surface area derived from MST, the MIP@MST fiber exhibited excellent extraction performance for TSNAs, which was much superior to the commercially available SPME fibers. By coupling to high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), the outstanding analytical merits such as low method detection limits (ranging 0.1-6.7 ng L-1) and good reproducibility (intra-fiber and inter-fiber relative standard deviations ranging 4.1 %-11.6 % and 3.5 %-12.2 %, respectively) were achieved with the consumption of 8 mL water sample and 100 µL methanol solvent in 50 min. The feasibility of the SPME-HPLC-MS/MS method was demonstrated in tap water and chloraminated source water, with relative recoveries for the five TSNAs ranging from 85.2 % to 108.5 %. In result, none of the TSNAs were found in the tap water samples, while 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-Butanol (NNAL) were detected in the chloraminated source water samples. The rapid and convenient SPME-HPLC-MS/MS method developed in this study offers a powerful tool for monitoring TSNAs in water.


Asunto(s)
Nitrosaminas , Microextracción en Fase Sólida , Microextracción en Fase Sólida/métodos , Nicotiana/química , Nitrosaminas/análisis , Agua , Polímeros Impresos Molecularmente/análisis , Espectrometría de Masas en Tándem/métodos , Dióxido de Silicio/química , Reproducibilidad de los Resultados , Extracción en Fase Sólida/métodos
10.
Chin J Dent Res ; 26(4): 257-264, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38126371

RESUMEN

OBJECTIVE: To evaluate the effects of powered and manual tooth brushing on gingival inflammation in a Chinese population with mild to moderate gingivitis. METHODS: The present randomised, single-blind, parallel clinical trial was conducted in five cities in China. Generally healthy participants aged 18 to 65 years, who were non-smokers and had at least 20 sites of gingival bleeding, were included as eligible subjects. The subjects were randomly assigned to either the powered tooth brushing (PTB) group or standard manual tooth brushing (MTB) group. All subjects were supplied with a fluoride-containing toothpaste, Gingival Bleeding Index (GBI), Modified Gingival Index (MGI) and the Turesky modification of the Quigley-Hein Plaque Index (MPI) were used to evaluate the outcomes. RESULTS: A total of 235 subjects completed the study, 118 in the PTB group and 117 in the MTB group. The mean age and sex distribution for the PTB and MTB groups were 34.40 ± 9.99 years, 89 women and 29 men, and 34.20 ± 10.14 years, 82 women and 35 men, respectively. After 6 months, the percentage decrease in MGI was 26.150% ± 26.897% for the PTB group and 14.768% ± 38.544% for the MTB group (P = 0.0092). Statistically significant differences between types of tooth brushing were also observed at 6 months for GBI, and at all time points for MPI. CONCLUSION: Tooth brushing with a powered toothbrush twice a day was shown to be more effective than use of a manual toothbrush in reducing gingival inflammation, gingival bleeding and surface plaque after a 6-month period. Both kinds of toothbrushes were safe for the oral tissues.


Asunto(s)
Gingivitis , Cepillado Dental , Femenino , Humanos , Masculino , China , Índice de Placa Dental , Diseño de Equipo , Hemorragia Gingival , Gingivitis/prevención & control , Inflamación , Método Simple Ciego , Pastas de Dientes , Adulto
11.
J Drug Target ; 30(1): 82-93, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33775195

RESUMEN

Tumour-associated macrophages (TAMs) represent an attractive cell target for anticancer therapy. However, selective and efficient targeting of TAMs remains difficult. Here, we constructed a novel dually functionalised nanoparticle platform (s-Tpep-NPs) by surface co-modification of nanoparticles (NPs) with tuftsin (Tpep) and legumain protease-sheddable polyethylene glycol 5k (PEG5k) to achieve selective targeted delivery to TAMs. The fluorescence resonance energy transfer experiment and in vitro cellular uptake assay confirmed that s-Tpep-NPs can responsively shed PEG5k and transform into active Tpep-NPs upon the cleavage of legumain that is overexpressed on TAM surfaces, which then promotes TAM phagocytosis through Fc receptor-mediated pathways. Owing to the shielding effect by legumain-sheddable PEG5k, s-Tpep-NPs can effectively decrease the Tpep-induced non-specific accumulation in mononuclear phagocyte system (MPS) organs during systemic circulation. Moreover, s-Tpep-NPs can significantly enhance the tumoural accumulation and improve the specificity and efficiency of targeting to TAMs, as compared with both controls of Tpep-NPs and non-sheddable ns-Tpep-NPs. Overall, this study provides a robust nanoplatform with a novel avenue for improved selectivity of targeted delivery to TAMs.


Asunto(s)
Nanopartículas , Tuftsina , Cisteína Endopeptidasas , Péptido Hidrolasas , Polietilenglicoles , Macrófagos Asociados a Tumores
12.
J Hazard Mater ; 424(Pt B): 127465, 2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-34655872

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs), as a major source that significantly increase the risk of developing lung cancer, severely jeopardize public health in modern society. The analysis of PAHs and their metabolites (hydroxylated PAHs, OH-PAHs) is important for biomonitoring and exposure assessment. However, due to the difference in their physico-chemical properties and matrix interference, realizing high-performance extraction of both PAHs and OH-PAHs is still a challenge. Herein, a nickel-doped hierarchical porous carbon (Ni/HPC) is synthesized by carbonizing the polystyrene (PS) infiltrated metal-organic frameworks (MOF-74(Ni)). The obtained Ni/HPC exhibits hierarchical pores and evenly distributed Ni atoms, providing efficient diffusion pathways and adsorption sites. The custom Ni/HPC-coated solid-phase microextraction (SPME) fiber shows superior enrichment capabilities for PAHs and their metabolites under various interfering conditions, verifying its practicability in real sample analysis. The proposed method provides a new strategy to synthesize carbon-based adsorbents that achieves matrix-resistant enrichment of PAHs and OH-PAHs, which simplifies the related sample preparation process for environmental analysis and clinical diagnosis.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Carbono , Humanos , Límite de Detección , Hidrocarburos Policíclicos Aromáticos/análisis , Poliestirenos , Porosidad , Microextracción en Fase Sólida , Contaminantes Químicos del Agua/análisis
13.
Macromol Biosci ; 22(12): e2200321, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36057971

RESUMEN

Poly (ether-ether-ketone) (PEEK) displays promising potential application in bone tissue repair and orthopedic surgery due to its good biocompatibility and chemical stability. However, the bio-inertness and poor mechanical strength of PEEK greatly limit its application in load-bearing bones. In this study, calcium silicate whiskers (CSws) are synthesized and then compounded with PEEK to fabricate the PEEK/CSw composites with excellent mechanical properties, biological activity. Compared with PEEK, the PEEK/CSw composites exhibited higher hydrophilicity and ability to deposit hydroxyapatite on the surface. CSws are evenly dispersed in the PEEK matrix at 10 wt% content and the mechanical strength of the PEEK/CSw composite is ≈96.9 ± 2.4 MPa, 136.3 ± 2.4 MPa, and 266.0 ± 3.2 MPa, corresponding to tensile strength, compressive strength, and bending strength, respectively, which is 20%, 18%, and 52% higher than that of pure PEEK. The composites improve the adhesion, proliferation, and osteogenic differentiation of BMSCs. Furthermore, PEEK/CSw composite remarkably improves bone formation and osteointegration, which has higher bone repair capacity than PEEK. These results demonstrate that the PEEK/CSw scaffolds display superior abilities to integrate with the host bone and promising potential in the field of load bearing bone repair.


Asunto(s)
Cetonas , Osteogénesis , Animales , Cetonas/farmacología , Cetonas/química , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/química , Éter , Polietilenglicoles/farmacología , Polietilenglicoles/química , Vibrisas , Éteres
14.
Yao Xue Xue Bao ; 46(4): 406-11, 2011 Apr.
Artículo en Zh | MEDLINE | ID: mdl-21751494

RESUMEN

The aim of this study is to establish a simple and stable model like poloxamer 407 (P-407)-induced dyslipidemia of golden hamster model, and investigate the mechanism of lipid metabolism disturbance in this model. PPARalpha agonist and HMG-CoA reductase inhibitor were administrated to validate the efficacy on regulating lipid metabolism in the dyslipidemia golden hamster model. Six weeks male golden hamsters were chosen to inject P-407 intraperitoneally at a bolus dose of 300 mg x kg(-1), an intermittent injection at a dose of 200 mg x kg(-1) every 72 hours after the bolus. The results showed that P-407-induced golden hamster model characterized as increased serum triglyceride (TG), total cholesterol (TC), free cholesterol (free-CHO), cholesteryl ester (CE), free fatty acids (FFA) and apoB levels, and the hyperlipidemia state maintained at a stable level persistently. Meanwhile, augmented malondialdehyde (MDA) and nitric oxide (NO) level was observed. LCAT and SR-B I mRNA levels in liver of model group were down-regulated (expression ratio is 0.426; 0.783), while HMG-CoA reductase mRNA level was up-regulated (expression ratio is 1.493) compared with those of the normal group. The serum cholesterol and triglyceride levels were significantly lower in P-407-induced dyslipidemia hamster model after treated with atorvastatin (Ato) at a dose of 50 mg x kg(1) or fenofibrate (Fen) at 100 mg x kg(-1) for two weeks. These findings suggest that serum lipid distribution in dyslipidemia golden hamster is similar to that of human, and which may be relevant to the disturbance of the enzymes expression involved in lipid metabolism in liver. Results obtained from this study support the concept that dyslipidemia golden hamster may be an adequate animal model to evaluate the efficacy of lipid-lowering agents.


Asunto(s)
Modelos Animales de Enfermedad , Dislipidemias/metabolismo , Fenofibrato/farmacología , Ácidos Heptanoicos/farmacología , Pirroles/farmacología , Animales , Anticolesterolemiantes/farmacología , Atorvastatina , Antígenos CD36/genética , Antígenos CD36/metabolismo , Cricetinae , Dislipidemias/inducido químicamente , Hidroximetilglutaril-CoA Reductasas/genética , Hidroximetilglutaril-CoA Reductasas/metabolismo , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Hipolipemiantes/farmacología , Metabolismo de los Lípidos , Hígado/metabolismo , Masculino , Malondialdehído/metabolismo , Mesocricetus , Óxido Nítrico/metabolismo , PPAR alfa/agonistas , Fosfatidilcolina-Esterol O-Aciltransferasa/genética , Fosfatidilcolina-Esterol O-Aciltransferasa/metabolismo , Poloxámero , ARN Mensajero/metabolismo , Superóxido Dismutasa/metabolismo
15.
ACS Appl Mater Interfaces ; 13(8): 9729-9738, 2021 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-33599495

RESUMEN

Intracerebral hemorrhage (ICH) will be accompanied by the overload of iron and reactive oxygen species (ROS) following hematoma clearance. Although deferoxamine (DFO) has been widely utilized as a clinical first-line siderophore to remove the iron overload, the ROS-inducing damage still greatly limits the therapeutic effect of DFO. To address this issue, we designed and fabricated a series of dual-functional macromolecular nanoscavengers featuring high-density DFO units and catechol moieties. Note that the former units could effectively remove the iron overload, while the latter ones could efficiently deplete the ROS. The resulting nanoscavengers efficiently down-regulate the iron and ROS levels as well as significantly reduce the cell death in both iron-overloaded RAW 264.7 cells and the ICH mice model. This work suggests a novel clue for the ICH-ameliorated iron-depleting interventional therapeutic regimen.


Asunto(s)
Antioxidantes/uso terapéutico , Hemorragia Cerebral/tratamiento farmacológico , Sobrecarga de Hierro/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Polímeros/uso terapéutico , Sideróforos/uso terapéutico , Animales , Antioxidantes/síntesis química , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/fisiopatología , Catecoles/síntesis química , Catecoles/uso terapéutico , Hemorragia Cerebral/inducido químicamente , Hemorragia Cerebral/complicaciones , Hemorragia Cerebral/fisiopatología , Colagenasas , Deferoxamina/análogos & derivados , Deferoxamina/uso terapéutico , Hierro/metabolismo , Sobrecarga de Hierro/etiología , Sobrecarga de Hierro/fisiopatología , Masculino , Ratones , Ratones Endogámicos BALB C , Fármacos Neuroprotectores/síntesis química , Polímeros/síntesis química , Células RAW 264.7 , Especies Reactivas de Oxígeno/metabolismo , Sideróforos/síntesis química
16.
Talanta ; 195: 290-297, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-30625545

RESUMEN

Herein, a robust and homogeneous porous poly(3,4-ethylenedioxythiophene)/graphene (PEDOT/graphene) thin film surface-assisted laser desorption/ionization (SALDI) functional platform was prepared through a rapid and facile in-situ photopolymerization method. The graphene-embedded PEDOT skeleton well circumvented the aggregation-related problems in the traditional carbon-based SALDI method which combined with time-of-flight mass spectrometer (TOF MS). As a result, the reproducibility and quantitative capacity of the SALDI platform were significantly improved. Furthermore, the highly efficient adsorption performance of the PEDOT/graphene thin film was demonstrated in terms of in vitro and in vivo solid-phase microextraction (SPME) extraction. It showed that porous morphology with abundant graphene doping favored the adsorption and enrichment of target analytes. Owing to the excellent adsorption capability of the PEDOT/graphene thin film and the inherent strong laser absorption ability of graphene, expected SALDI effect (3-13 times higher than the commercial nanomaterial-assisted LDI plate) and quantitative analysis (linear range 0.5-100 µg L-1) of the PEDOT/graphene functional surfaces were achieved. As for the real-world applications, we deployed the PEDOT/graphene thin film SALDI platform for the analysis of five estrogens in biological samples at microliter-volume level, without tedious sample preparation procedures. Satisfactory recoveries ranging from 60.6% to 99.0% were obtained. The present study suggested that the graphene-embedded PEDOT skeleton with porous morphology would be developed as promising coating for the adsorption of analytes of interest. Additionally, the combination of PEDOT with graphene not only expanded the application fields of PEDOT, but also offered an efficient strategy for preparing homogeneous functional surfaces to realize the quantitative analysis in SALDI method.


Asunto(s)
Compuestos Bicíclicos Heterocíclicos con Puentes/química , Estrógenos/análisis , Grafito/química , Polímeros/química , Adsorción , Animales , Bovinos , Estrógenos/química , Humanos , Músculos/química , Microextracción en Fase Sólida , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Tilapia
17.
J Hazard Mater ; 364: 531-536, 2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-30388636

RESUMEN

It has been reported that nanoplastics (NP) could cause serious toxicity and accumulative effects on aquatic organisms as well as interact with organic pollutants and influence potential hazards when exposed to biota. The current study aimed to quantitatively investigate the combined acute toxic effect of polychlorinated biphenyls (PCBs) and nano-sized polystyrene (PS) plastic on aquatic organisms based on analyte speciation. First, the combined acute toxicity of PCB-18 and 100 nm PS to Daphnia magna (D. magna) in water was evaluated. Then, speciation analysis of the exposure system was conducted by measuring the sorption coefficients (logKNP) of PCBs to nano-sized PS (ranging from 5.28 to 6.56), which demonstrated the PS could substantially decrease the free concentrations of PCBs. The results showed that a low concentration of the PS could decrease the toxicity to D. magna., which might be originated from the decreased free concentration of PCB-18. However, when the PS concentration was high enough, an opposite effect was observed because the PS dominated the lethality instead of PCB-18. The current study is helpful to clarify the PCB occurrence in ecosystems and provide an in-depth understanding of the eco-toxicological effects of nanoscale plastics.


Asunto(s)
Daphnia/efectos de los fármacos , Nanopartículas/toxicidad , Bifenilos Policlorados/toxicidad , Poliestirenos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Adsorción , Animales , Nanopartículas/química , Bifenilos Policlorados/química , Poliestirenos/química , Contaminantes Químicos del Agua/química
18.
Artículo en Inglés | MEDLINE | ID: mdl-31569796

RESUMEN

BACKGROUND: A few studies have explored the association between meteorological factors and hand, foot, and mouth disease (HFMD) with inconsistent results. Besides, studies about the effects of air pollutants on HFMD are very limited. METHODS: Daily HFMD cases among children aged 0-14 years in Shenzhen were collected from 2009 to 2017. A distributed lag nonlinear model (DLNM) model was fitted to simultaneously assess the nonlinear and lagged effects of meteorological factors and air pollutants on HFMD incidence, and to further examine the differences of the effect across different subgroups stratified by gender, age and childcare patterns. RESULTS: The cumulative relative risk (cRR) (median as reference) of HFMD rose with the increase of daily temperature and leveled off at about 30 °C (cRR: 1.40, 95%CI: 1.29, 1.51). There was a facilitating effect on HFMD when relative humidity was 46.0% to 88.8% (cRR at 95th percentile: 1.18, 95%CI: 1.11, 1.27). Short daily sunshine duration (5th vs. 50th) promoted HFMD (cRR: 1.07, 95%CI: 1.02, 1.11). The positive correlation between rainfall and HFMD reversed when it exceeded 78.3 mm (cRR: 1.41, 95% CI: 1.22, 1.63). Ozone suppressed HFMD when it exceeded 104 µg /m3 (cRR at 99th percentile: 0.85, 95%CI: 0.76, 0.94). NO2 promoted HFMD among infants and the cRR peaked at lag 9 day (cRR: 1.47, 95%CI: 1.02, 2.13) (99th vs. 50th). Besides, children aged below one year, males and scattered children were more vulnerable to high temperature, high relative humidity, and short sunshine duration. CONCLUSIONS: Temperature, relative humidity, sunshine duration, rainfall, ozone and NO2 were significantly associated with HFMD, and such effects varied with gender age and childcare patterns. These findings highlight the need for more prevention effort to the vulnerable populations and may be helpful for developing an early environment-based warning system for HFMD.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Contaminación del Aire/efectos adversos , Enfermedad de Boca, Mano y Pie/etiología , Conceptos Meteorológicos , Adolescente , Niño , Preescolar , China/epidemiología , Femenino , Enfermedad de Boca, Mano y Pie/epidemiología , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Dinámicas no Lineales , Factores de Riesgo
19.
Environ Sci Pollut Res Int ; 25(8): 7916-7923, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29299866

RESUMEN

Three polystyrene (PS) resin microspheres supported nanoscale zero-valent iron (nZVI), i.e., nZVI@PS, nZVI@PS-Cl, and nZVI@PS-N, were prepared and characterized by FT-IR, XPS, SEM, EDS, and weighing method. The functional groups on the carriers showed obvious influence on the loading quantity, the micro morphology, and the reduction efficiency of these supported nZVI. The best hybrid reducer was nZVI@PS-N. The load quantity of nZVI was 0.2476 g/g, and some of them were dispersed and the others remained as particles (≤ 50 nm). At optimal reaction conditions, i.e., initial solution pH = 3, 25 °C, 100 r/min stirring, 99% nitrobenzene (NB) in 250 mL 123.1 mg/L NB solution could be totally reduced into AN by 1.31 g fresh nZVI@PS-N within 20 min. The excellent reduction efficiency and fast degradation rate of nZVI@PS-N were mainly attributed to the synergistic effects between the good adsorption property of its carrier and the high reduction activity of nZVI particles. NZVI@PS-N was reproducible and recycled, and 90.6% degradation ratio of NB was till obtained at its seventh recycle. The results showed that nZVI@PS-N had high potential practical application value in the reductive degradation and emergency rescue of nitrobenzene pollutant.


Asunto(s)
Hierro/química , Microesferas , Nitrobencenos/química , Poliestirenos/química , Contaminantes Químicos del Agua/química , Adsorción , Concentración de Iones de Hidrógeno , Nitrobencenos/aislamiento & purificación , Reciclaje , Temperatura , Contaminantes Químicos del Agua/aislamiento & purificación
20.
J Control Release ; 273: 160-179, 2018 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-29382547

RESUMEN

Polymeric scaffolds have attracted great interests in recent years, due to their fascination with a large variety of examples with promising utilization. Recently, extensive efforts have been devoted to the exploitation of robust and functional polymer-based biomaterial scaffolds with high efficiency. The recent entry of so-called "click" reactions that include kinds of selective and orthogonal reactions under mild conditions have generated real stimulus not only in preparing elegant bioactive materials of choice but also in making the leap to industrial scale build-up of multifunctional products. In this review paper, we account several kinds of polymeric scaffolds prepared/modified via "click" reactions, with emphasis on their synthetic/functionalized strategies, tunable properties, and biomedical applications.


Asunto(s)
Química Clic , Andamios del Tejido , Animales , Humanos , Polímeros/química , Ingeniería de Tejidos
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