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1.
Ecotoxicol Environ Saf ; 241: 113843, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36068765

RESUMEN

Microplastics (MPs), due to their impacts on the ecosystem and their integration into the food web either through trophic transfer or ingestion directly from the ambient environment, are an emerging class of environmental contaminants posing a great threat to marine organisms. Most reports on the toxic effects of MPs exclusively focus on bioaccumulation, oxidative stress, pathological damage, and metabolic disturbance in fish. However, the collected information on fish immunity in response to MPs is poorly defined. In particular, little is known regarding mucosal immunity and the role of mucins. In this study, marine medaka (Oryzias melastigma) larvae were exposed to 6.0 µm beads of polystyrene microplastics (PS-MPs) at three environmentally relevant concentrations (102 particles/L, 104 particles/L, and 106 particles/L) for 14 days. The experiment was carried out to explore the developmental and behavioural indices, the transcriptional profiles of mucins, pro-inflammatory, immune, metabolism and antioxidant responses related genes, as well as the accumulation of PS-MPs in larvae. The results revealed that PS-MPs were observed in the gastrointestinal tract, with a concentration- and exposure time-dependent manner. No significant difference in the larval mortality was found between the treatment groups and the control, whereas the body length of larvae demonstrated a significant reduction at 106 particles/L on 14 days post-hatching. The swimming behaviour of the larvae became hyperactive under exposure to 104 and 106 particles/L PS-MPs. In addition, PS-MP exposure significantly up-regulated the mucin gene transcriptional levels of muc7-like and muc13-like, however down-regulated the mucin gene expression levels of heg1, muc2, muc5AC-like and muc13. The immune- and inflammation and metabolism-relevant genes (jak, stat-3, il-6, il-1ß, tnf-а, ccl-11, nf-κb, and sod) were significantly induced by PS-MPs at 104 and 106 particles/L compared to the control. Taken together, this study suggests that PS-MPs induced inflammation response and might obstruct the immune functions and retarded the growth of the marine medaka larvae even at environmentally relevant concentrations.


Asunto(s)
Oryzias , Contaminantes Químicos del Agua , Animales , Ecosistema , Inmunidad , Inflamación , Larva , Microplásticos/toxicidad , Mucinas/genética , Mucinas/metabolismo , Oryzias/metabolismo , Plásticos/toxicidad , Poliestirenos/metabolismo , Poliestirenos/toxicidad , Natación , Contaminantes Químicos del Agua/análisis
2.
J Craniofac Surg ; 29(8): e818-e824, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30320686

RESUMEN

Clinically, patients with operated unilateral cleft lip and palate always present with a concave profile, depressed midface, maxillary hypoplasia, narrow upper dental arch, and class III malocclusion. In this clinical report, the authors describe the successful orthodontic treatment of a patient with unilateral cleft lip and palate. A boy, 7 years 11 months of age, with a history of unilateral cleft lip and cleft palate presented with a Class I malocclusion on Skeletal Class III base. A satisfactory occlusion and a favorable lateral profile were achieved after maxillary protraction (face mask) combined with fixed appliance treatment, including alveolar bone grafting surgery. An acceptable occlusion and facial proportion were maintained after a 3-year retention period. These results suggest orthodontic treatment with growth interference is an effective option for a patient with cleft lip and palate.


Asunto(s)
Labio Leporino/cirugía , Fisura del Paladar/cirugía , Aparatos de Tracción Extraoral , Maloclusión de Angle Clase III/terapia , Maxilar/cirugía , Injerto de Hueso Alveolar , Cefalometría , Niño , Labio Leporino/diagnóstico por imagen , Fisura del Paladar/diagnóstico por imagen , Oclusión Dental , Estudios de Seguimiento , Humanos , Masculino , Maloclusión de Angle Clase III/diagnóstico por imagen , Maxilar/diagnóstico por imagen , Desarrollo Maxilofacial
3.
Int J Biol Macromol ; 259(Pt 2): 129327, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38219939

RESUMEN

A series of novel waterborne lignin-based epoxy resin emulsions (WLEPs) were successfully synthesized, and then the WLEPs were cured with polyamide (PA) to give formaldehyde-free wood adhesives with high-performance. The chemical structures and properties of WLEP emulsions were determined. The effects of the emulsifiers on thermal and mechanical properties of the adhesives were investigated, and the potential application of WLEPs in the formulation of plywood were also evaluated. The results demonstrated that the WLEP dispersions presented excellent storage stability (>180 days) with their viscosities range from 110 mPa·s to 470 mPa·s and particle sizes in the range of 321-696 nm, which were beneficial for the fluidity and permeability of the wood adhesives. Furthermore, the thermal and mechanical properties of adhesives could be tuned effectively by controlling the length of PEG chains. The adhesive bearing PEG 6000 exhibited the highest tensile strength of 24.0 MPa and Young's modulus of 1439 MPa. Notably, the plywood prepared with the resulting adhesives displayed good bonding performance, especially water resistance, which were much higher than the national standard requirement for exterior-grade plywood type I. These results indicated that the WLEPs could be used as sustainable alternatives for traditional formaldehyde-based wood adhesives in practical applications.


Asunto(s)
Resinas Epoxi , Lignina , Lignina/química , Adhesivos/química , Madera/química , Resistencia a la Tracción
4.
Int J Biol Macromol ; 260(Pt 2): 129677, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38266831

RESUMEN

In this study, a simple and eco-friendly method was used to treat alkaline lignin with an acidic deep eutectic solvent (DES) to obtain regenerated lignin for the efficient adsorption of pollutant dyes from aqueous environment. Based on the yield and adsorption capacity of the sorbent for these dyes, conditions such as the type and concentration of DES component, solid-to-liquid ratio, reaction time, and temperature were optimized. By characterizing and comparing alkali lignin with regenerated lignin, a series of reactions were demonstrated to occur during the DES treatment process. The performance and mechanism of methylene blue and rhodamine B adsorption on regenerated lignin were studied systematically, and the maximum adsorbed amounts were 348.29 and 551.05 mg/g at 323 K, respectively. This study provides a new strategy for the green preparation of functionalized lignin and its use in the water pollutant treatment.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Lignina , Agua , Colorantes , Disolventes Eutécticos Profundos , Adsorción , Contaminantes Químicos del Agua/análisis , Solventes
5.
Int J Biol Macromol ; 270(Pt 1): 132148, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38723800

RESUMEN

Herein, a straightforward protocol was developed for the one-pot synthesis of N-doped lignosulfonate-derived carbons (NLDCs) with a tunable porous structure using natural amino acids-templated self-assembly strategy. Specifically, histidine was employed as a template reagent, leading to the preparation of 10-NLDC-21 with remarkable characteristics, including the large specific surface area (SBET = 1844.5 m2/g), pore volume (Vmes = 1.22 cm3/g) and efficient adsorption for atrazine (ATZ) removal. The adsorption behavior of ATZ by NLDCs followed the Langmuir and pseudo-second-order models, suggesting a monolayer chemisorption nature of ATZ adsorption with the maximum adsorption capacity reached up to 265.77 mg/g. Furthermore, NLDCs exhibited excellent environmental adaptability and recycling performance. The robust affinity could be attributed to multi-interactions including pore filling, electrostatic attraction, hydrogen bonding and π-π stacking between the adsorbents and ATZ molecules. This approach offers a practical method for exploring innovative bio-carbon materials for sewage treatment.


Asunto(s)
Atrazina , Carbono , Lignina , Contaminantes Químicos del Agua , Atrazina/química , Lignina/química , Lignina/análogos & derivados , Porosidad , Adsorción , Carbono/química , Concentración de Iones de Hidrógeno , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Cinética
6.
Chemosphere ; 316: 137798, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36634714

RESUMEN

Efficient and feasible removal of trace antibiotics from wastewater is extremely important due to its environmental persistence, bioaccumulation, and toxicity, but still remains a huge challenge. Herein, three natural phenol-inspired porous organic polymers were fabricated from natural phenolic-derived monomers (p-hydroxy benzaldehyde, 2,4-dihydroxy benzaldehyde and 2,4,6-trihydroxy benzaldehyde) and melamine via polycondensation reaction. Characterization highlighted that the increasing contents of hydroxyl groups in monomers induced an increase of the polymer total porosity and promoted the formation of a highly microporous structure. With mesopore-dominated pore (average pore diameter 9.6 nm) and large pore volume (1.78 cm3/g), p-hydroxy benzaldehyde-based porous polymer (1-HBPP) exhibited ultra-high maximum adsorption capacity (qmax) of 697.6 mg/g for tetracycline (TC) antibiotic. Meanwhile, the porous networks and plentiful active sites of 1-HBPP enabled fast adsorption kinetics (within 10 min) for TC removal, which could be well described by the pseudo-second-order model. Dynamic adsorption studies showed that 1-HBPP could be used in fixed-bed adsorption column (FBAC) with high removal efficiency (breakthrough volume per unit mass, 13.2 L/g) and dynamic adsorption capacity (201.6 mg/g), which were much higher than other reported adsorbents. The breakthrough curves both well matched with Thomas and Yoon-Nelson models in FBAC treatment. Moreover, removal mechanism analysis affirmed that pore-filling, hydrogen bonding, electrostatic interactions and π-π stacking interactions were main driving forces for TC adsorption. The prepared natural phenol-inspired porous adsorbents show great potential in antibiotics removal from wastewater, and this strategy would promote the sustainable and high-value utilization of natural phenolic compounds.


Asunto(s)
Fenol , Contaminantes Químicos del Agua , Fenol/química , Porosidad , Benzaldehídos , Aguas Residuales , Tetraciclina , Antibacterianos , Fenoles , Polímeros/química , Adsorción , Contaminantes Químicos del Agua/química , Cinética
7.
ACS Appl Mater Interfaces ; 14(1): 383-389, 2022 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-34978181

RESUMEN

Plasmonic bimetal nanostructures can be employed to amplify electrochemiluminescence (ECL) signals. In this work, a high-performance ECL platform was constructed using a europium metal-organic framework (MOF) as a luminophore and Au-Pt bimetallic nanorods (NRs) as a plasma source. Due to the SPR effect of Au-Pt NRs, the aptasensor exhibits 2.6-fold ECL intensity compared to that of pure polyaniline (PANI)-decorated perylene tetracarboxylic dianhydride (PTCA)/Eu MOF. Moreover, decoration with PTP greatly enhances the conductivity and stability of Eu MOF, resulting in sizeable plasmon-enhanced electrochemical luminescence. The as-designed plasmon-enhanced ECL aptasensor displayed highly sensitive detection for lincomycin (Lin). The as-proposed aptasensor could quantify Lin from 0.1 mg/mL to 0.1 ng/mL with a limit of detection (LOD) of 0.026 ng/mL.


Asunto(s)
Materiales Biocompatibles/química , Técnicas Electroquímicas , Lincomicina/análisis , Mediciones Luminiscentes , Estructuras Metalorgánicas/química , Anhídridos/química , Compuestos de Anilina/química , Animales , Europio/química , Oro/química , Ensayo de Materiales , Leche/química , Tamaño de la Partícula , Perileno/análogos & derivados , Perileno/química , Platino (Metal)/química
8.
Int J Biol Macromol ; 193(Pt B): 1400-1408, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34740690

RESUMEN

A series of lignin-based epoxy resins (LEPs) were prepared by the reaction of epichlorohydrin with lignin oligomers derived from partial reductive depolymerization of lignin. To overcome the high viscosity and brittleness defects in practical applications, the LEPs were blended with renewable epoxied cardanol glycidyl ether (ECGE) and then cured with methyltetrahydrophthalic anhydride (MeTHPA) to form high-performance epoxy thermosets. The effects of degree of lignin depolymerization, chemical composition of lignin oligomers and dosage of ECGE on thermal and mechanical properties of the cured products were investigated. The LEP/MeTHPA thermosets exhibited good thermal and mechanical properties. Especially, by separating monomer-rich fractions from lignin oligomers, the thermal and mechanical properties of the cured product were improved obviously. Notably, the incorporation of ECGE also possessed a positive effect on reinforcing and toughening the cured products. With 20 wt% ECGE loadings, the tensile, flexural and impact strength of the cured product reached the maximum value of 77 MPa, 115 MPa and 14 kJ/m2, respectively, which were equivalent to the commercial bisphenol A epoxy resins thermosets. These findings indicated that the novel bio-based epoxy resins from lignin oligomers and cardanol could be utilized as renewable alternatives for BPA epoxy resins.


Asunto(s)
Resinas Epoxi/química , Lignina/química , Fenoles/química , Compuestos de Bencidrilo/química , Epiclorhidrina/química , Compuestos Epoxi/química , Anhídridos Ftálicos/química , Temperatura , Viscosidad
9.
Int J Biol Macromol ; 187: 880-891, 2021 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-34329666

RESUMEN

Water pollution is one of the most serious threats facing mankind today and has obtained widespread attention. Significant advances have been made in the past decades to apply porous materials in wastewater treatment, due to their large specific surface areas (SBET) for interaction with the aimed ions or molecules. However, the majority of porous materials are prepared from fossil-based resources and still possess some drawbacks, such as high cost and non-degradability, which inevitably cause secondary pollution to the environment from their production to disposal. Lignin is the most abundant and the only scalable renewable aromatic resource on earth. Due to its unique physicochemical properties including high carbon content, plentiful functional groups and environmental friendliness, the lignin-based porous materials (LPMs) have shown promising prospects in efficient removal of soluble pollutants from wastewater. In this review, we firstly described the structural and chemical basis of LPMs, following presented the recent progress in the decontamination of heavy metal ions, organic dyes, antibiotics, anions and radionuclides from aqueous systems. Additionally, the outlook was provided to promote more practical implementation of LPMs in the near future.


Asunto(s)
Lignina/química , Aguas Residuales/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua , Hidrogeles , Porosidad , Solubilidad , Propiedades de Superficie
10.
Mar Environ Res ; 167: 105295, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33714106

RESUMEN

Marine biota, especially commercially important species, serves as a basis for human nutrition. However, millions of tons of plastic litter are produced and enter the marine environment every year, with potential adverse impacts on marine organisms. In the present study, we investigated the occurrence and characteristics of microplastic (MP) pollution in the digestive tracts of 13 species of wild nektons from 20 stations sampled in the South China Sea (SCS) and the Indian Ocean (IO), and assessed the human health risks of MPs. The detection rate of MPs ranged from 0.00% to 50.00% from the SCS, which was dramatically lower than that from the IO (10.00-80.00%). The average abundance of MP was 0.18 ± 0.06 items g wet weight-1 (ww-1) in the SCS, which was significantly lower than that in the IO with a concentration of 0.70 ± 0.16 items g ww-1. Most MPs were fibers in type, black in color, and polyester (PES) in polymer composition in both the SCS and IO. Interestingly, distinct profiles of MP pollution were found between the benthic and pelagic nektons: 1) The predominant MP composition was PES in the benthic nektons, whereas polyamide (PA) accounted for a larger part of the total MP count in the pelagic nektons within the SCS; 2) The abundance of MP in the benthic nektons (0.52 ± 0.24 items individual-1) was higher than that in the pelagic nektons (0.30 ± 0.11 items individual-1). Accordingly, the mean hazard score of MPs detected in the benthic nektons (220.66 ± 210.75) was higher than that in the pelagic nektons (49.53 ± 22.87); 3) The mean size of the MP in the pelagic nektons (0.84 ± 0.17 mm) was larger than that in the benthic nektons (0.49 ± 0.09 mm). Our findings highlight the need to further investigate the ecological impacts of MPs on wild nekton, especially commercially important species, and its potential implications for human health.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , China , Monitoreo del Ambiente , Humanos , Océano Índico , Plásticos , Contaminantes Químicos del Agua/análisis
11.
Mar Pollut Bull ; 158: 111349, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32573451

RESUMEN

Microplastic (MP) pollution is an emerging contaminant in aquatic environments worldwide. Nonetheless, the developmental toxicity of MPs in the early life stages of fish and the mechanisms involved are not yet fully understood. The present study investigated the effects of different concentrations of polystyrene (PS) MPs on the early development of the marine model fish the medaka Oryzias melastigma. Our results showed that waterborne exposure to PS MPs significantly delayed the hatching time, altered the heartbeat and decreased the hatching rate of embryos. Furthermore, the genes involved in cardiac development, encoding for embryo-hatching enzymes, as well as inflammatory responses were significantly upregulated. The transcriptome results showed that mainly the pathways involved in metabolism, immune response, genetic information processing and diseases were significantly enriched. These results demonstrate that PS MPs negatively impact embryogenesis and the immune response of O. melastigma.


Asunto(s)
Oryzias , Contaminantes Químicos del Agua , Animales , Desarrollo Embrionario , Microplásticos , Plásticos
12.
Onco Targets Ther ; 11: 1617-1623, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29606880

RESUMEN

BACKGROUND: Previous studies have indicated that tooth loss is associated with colorectal cancer risk but have presented controversial results. METHODS: We conducted a dose-response meta-analysis in order to investigate the correlation between tooth loss and colorectal cancer risk. Up to August 2017, six eligible studies were included in this meta-analysis. RESULTS: Our results showed statistically significant association between tooth loss and colorectal cancer (OR =1.08, 95% CI: 1.03-1.15, P<0.001). In addition, we obtained the best fit at an inflection point of every two tooth loss in piecewise regression analysis, and the summary relative risk (RR) of colorectal cancer for an increase of every two tooth loss was 1.06 (95% CI: 1.02-1.11, P<0.001). Furthermore, tooth loss was significantly associated with colorectal cancer risk in Caucasia (RR: 1.18; 95% CI: 1.09-1.28; P<0.001) and Asia (RR: 1.06; 95% CI: 1.02-1.10; P<0.001). Moreover, tooth loss was significantly associated with a higher risk of colon cancer (RR: 1.09; 95% CI: 1.02-1.17; P<0.001) and rectal cancer (RR: 1.08; 95% CI: 1.01-1.17; P<0.001). CONCLUSION: Subgroup meta-analyses showed consistency with the primary findings. Considering these promising results, increasing tooth loss may be harmful to our health, and maintenance of our oral health is essential.

13.
Huan Jing Ke Xue ; 37(4): 1240-7, 2016 Apr 15.
Artículo en Zh | MEDLINE | ID: mdl-27548942

RESUMEN

In order to explore the residual characteristics of perfluorinated compounds (PFCs) in the atmosphere of Shenzhen, passive air samplers consisting of polyurethane foam (PUF) disks impregnated with XAD-4 power were deployed at 12 sites in Shenzhen from November 2014 to February 2015. Seven volatile and fifteen ionic PFCs were analyzed. The results indicated that ΣPFCs concentration ranged from 23.7 pg x m(-3) to 157 pg x m(-3) (mean: 79.0 pg x m(-3)), dominated by volatile PFCs, with 8:2 FTOITI, 6:2 FTOH, PFPeA, PFOA being the dominant compounds. The spatial distribution of volatile and ionic PFCs concentrations was the same, displaying the characteristic of "the northwest being higher than the southeast ". Furthermore, the concentrations of 6:2 FTOHs, 8:2 FTOHs, PFPeA, PFHxA and PFOA had positive correlations with PM2.5 and PM10 (P < 0.05, P < 0.01) and were more positively correlated with the levels of PM10 than those of PM2.5.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Fluorocarburos/análisis , Atmósfera/análisis , China , Ciudades , Iones , Tamaño de la Partícula , Poliuretanos
14.
J Biomed Mater Res B Appl Biomater ; 100(8): 2167-77, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22915482

RESUMEN

Surface modification of dental implants with biomolecules is of particularly interest recently. To mimic the structure and function of native extracellular matrix (ECM), a derivative of hyaluronic acid (HA), HA-GRGDSP, was synthesized, Arg-Gly-Asp (RGD)-containing collagen (Col)/HA multilayer polyelectrolyte films (MPFs) coating was fabricated on titanium (Ti) through alternate deposition of Col and HA-GRGDSP with 4.5 assembly cycles; moreover, bioactive molecule, basic fibroblast growth factor (bFGF), was also incorporated into such coating. This coating was then carefully characterized using scanning electronic microscope (SEM) and scanning force microscopy (SFM); bFGF release from the coating was also evaluated. (Col + bFGF)/HA-RGD coating was successfully deposited on Ti surface, and about 300 pg of bFGF could be slowly released from this coating for a week. This coating significantly promoted the initial cell attachment of human gingival fibroblasts (HGFs) compared with other groups (p < 0.05), and HGFs adhered and spread better on this coating than other groups (p < 0.05). Regarding cell proliferation and differentiation of HGFs, they were greatly stimulated when cultured on this coating (p < 0.05). These results indicated that surface modification of Ti using biomolecules might improve the sealing between the neck section of a dental implant and the soft tissue.


Asunto(s)
Diferenciación Celular , Proliferación Celular , Materiales Biocompatibles Revestidos/química , Colágeno/química , Fibroblastos/metabolismo , Encía/metabolismo , Ácido Hialurónico/química , Oligopéptidos/química , Titanio/química , Adulto , Adhesión Celular , Células Cultivadas , Fibroblastos/citología , Encía/citología , Humanos , Masculino , Ensayo de Materiales
15.
Shanghai Kou Qiang Yi Xue ; 14(3): 321-2, 2005 Jun.
Artículo en Zh | MEDLINE | ID: mdl-15995786

RESUMEN

48 patients with fractures of the jaw bones were included in this study. Intermaxillary fixation screws were used for tractions between the upper and lower jaw and to regain occlusion relationship, followed by internal rigid fixation. Two days after reduction of the fractures, intermaxillary tractions were carried out and the fixation screws remained for 2 weeks. All the wounds healed primarily with good occlusion. The wounds for screw placement healed well 3 to 5 days after removal of the screws. Excellent occlusion recovered in 45 patients, while in 3 patients, mild open bite developed which returned to normal after 2 weeks of intermaxillary tractions. It is concluded that intermaxillary fixation screws are time saving and efficient in the management of jaw fractures.


Asunto(s)
Fijación Interna de Fracturas , Técnicas de Fijación de Maxilares , Fracturas Maxilomandibulares/cirugía , Tornillos Óseos , Oclusión Dental , Humanos
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