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1.
J Periodontal Res ; 59(2): 325-335, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38116861

RESUMEN

OBJECTIVE: Investigating the changes in the oxidative stress levels and helper T lymphocyte (Th) subsets in patients with periodontitis and IgA nephropathy (IgAN) to determine their relationship. BACKGROUND: IgAN has a high prevalence, poor prognosis, and no effective cure. Accumulating evidence has implicated a close relationship between periodontitis and chronic kidney diseases, in which both IgAN and chronic periodontitis show chronic inflammation and abnormal metabolism. However, few studies have been conducted on the relationship between the two diseases from this perspective. METHODS: We divided 86 IgAN patients into patients with healthy periodontium (IgAN-H, n = 34) and patients with periodontitis IgAN (IgAN-P, n = 52); moreover, we divided 72 systemically healthy participants into patients with periodontitis (H-P, n = 35) and participants with healthy periodontium (H-H, n = 37). The proportions of Th subsets in peripheral blood were estimated using flow cytometry. Cytokine levels in plasma were assessed using cytokine assay kits. Enzyme-linked immunosorbent assay was used to evaluate the plasma levels of oxidative stress. RESULTS: Our results from analyzing the Th cell subsets indicated that Th2 cell counts in the IgAN-P group were significantly lower than those in the IgAN-H group, while Th17 cell counts were increased (p < 0.05). Moreover, the Th1/Th2 ratio and interleukin-6 levels in the IgAN-P group were significantly higher than those in the H-H group (p < 0.01). Compared with that in the H-H group, in the remaining three groups, plasma total oxidation state (TOS) levels were increased (p < 0.01), while plasma total antioxidant state (TAS) levels were decreased (p < 0.05). Furthermore, estimated glomerular filtration rate was negatively correlated with the probing depth and gingival bleeding index. IgAN was a risk factor for periodontitis, while TAS was a protective factor for periodontitis. The oxidative stress index (OSI) might be valuable for distinguishing periodontitis patients from healthy controls (area under the receiver operator characteristic curve = 0.951). CONCLUSION: IgAN is an independent risk factor of periodontitis, and the Th17 cell-mediated inflammatory response might be associated with the occurrence of periodontitis in patients with IgAN. Patients with coexisting IgAN and periodontitis exhibit increased oxidative stress, in which TOS and OSI are potential biomarkers for diagnosing periodontitis.


Asunto(s)
Periodontitis Crónica , Glomerulonefritis por IGA , Humanos , Glomerulonefritis por IGA/complicaciones , Glomerulonefritis por IGA/diagnóstico , Biomarcadores , Periodontitis Crónica/complicaciones , Citocinas , Células Th17 , Estrés Oxidativo
2.
World J Microbiol Biotechnol ; 39(9): 242, 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37400664

RESUMEN

Dextranase is a type of hydrolase that is responsible for catalyzing the breakdown of high-molecular-weight dextran into low-molecular-weight polysaccharides. This process is called dextranolysis. A select group of bacteria and fungi, including yeasts and likely certain complex eukaryotes, produce dextranase enzymes as extracellular enzymes that are released into the environment. These enzymes join dextran's α-1,6 glycosidic bonds to make glucose, exodextranases, or isomalto-oligosaccharides (endodextranases). Dextranase is an enzyme that has a wide variety of applications, some of which include the sugar business, the production of human plasma replacements, the treatment of dental plaque and its protection, and the creation of human plasma replacements. Because of this, the quantity of studies carried out on worldwide has steadily increased over the course of the past couple of decades. The major focus of this study is on the most current advancements in the production, administration, and properties of microbial dextranases. This will be done throughout the entirety of the review.


Asunto(s)
Dextranasa , Dextranos , Humanos , Dextranasa/química , Dextranasa/metabolismo , Dextranos/metabolismo , Bacterias/metabolismo , Hongos/metabolismo , Polisacáridos
3.
Am J Dent ; 35(1): 55-60, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35316594

RESUMEN

PURPOSE: To investigate the effect of type 2 diabetes mellitus (T2DM) and periodontitis on the Th1/Th2/Th17/Treg paradigm. METHODS: A total of 107 volunteers (aged 18-78 years) were recruited. Peripheral blood samples from patients with periodontitis and T2DM (n= 43), patients with periodontitis only (n= 20), patients with T2DM only (n= 23), and healthy controls (n= 21) were collected. Blood pressure, glycated hemoglobin, fasting plasma glucose, probing depth, gingival index, and clinical attachment loss were measured. The circulating proportions of Th1, Th2, Th17, and Treg cells were estimated by flow cytometry. The data were analyzed by a 2x2 factorial ANOVA. RESULTS: We observed higher ratios of Th1/Th2 and Th17/Treg cells among patients with T2DM (P< 0.05) than among healthy controls. The proportion of Th17 cells in patients with periodontitis and T2DM was higher than that in other groups (P< 0.05). T2DM exhibited a predominant effect on the proportion of Th1 cells (F= 18.127, P= 0.000) and the Th17/Treg ratio (F= 45.384, P= 0.000). A significant "T2DM x periodontitis" interaction effect on the proportion of Th2, Th17, Treg cells, and the Th1/Th2 ratio (P< 0.05) was also noticed. The area under curve of Th17 was 0.711 (95% CI= 0.584 to 0.803, P< 0.01) in the receiver operating characteristic curve analysis. CLINICAL SIGNIFICANCE: The results suggest that the proportion of Th2, Th17, Treg cells and the Th1/Th2 ratio is indicative of immune activation and inflammation, which are evident in patients with type 2 diabetes mellitus (T2DM) and periodontitis. The data indicate that the high expression of Th17 cells may be a relevant biological factor that can be associated with an increased risk of developing chronic periodontitis in patients with T2DM.


Asunto(s)
Diabetes Mellitus Tipo 2 , Periodontitis , Adolescente , Adulto , Anciano , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Persona de Mediana Edad , Linfocitos T Reguladores/metabolismo , Células TH1/metabolismo , Células Th17/metabolismo , Adulto Joven
4.
J Nanobiotechnology ; 19(1): 214, 2021 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-34275471

RESUMEN

BACKGROUND: Cartilage injury and pathological degeneration are reported in millions of patients globally. Cartilages such as articular hyaline cartilage are characterized by poor self-regeneration ability due to lack of vascular tissue. Current treatment methods adopt foreign cartilage analogue implants or microfracture surgery to accelerate tissue repair and regeneration. These methods are invasive and are associated with the formation of fibrocartilage, which warrants further exploration of new cartilage repair materials. The present study aims to develop an injectable modified gelatin hydrogel. METHOD: The hydrogel effectively adsorbed proteoglycans secreted by chondrocytes adjacent to the cartilage tissue in situ, and rapidly formed suitable chondrocyte survival microenvironment modified by ε-poly-L-lysine (EPL). Besides, dynamic covalent bonds were introduced between glucose and phenylboronic acids (PBA). These bonds formed reversible covalent interactions between the cis-diol groups on polyols and the ionic boronate state of PBA. PBA-modified hydrogel induced significant stress relaxation, which improved chondrocyte viability and cartilage differentiation of stem cells. Further, we explored the ability of these hydrogels to promote chondrocyte viability and cartilage differentiation of stem cells through chemical and mechanical modifications. RESULTS: In vivo and in vitro results demonstrated that the hydrogels exhibited efficient biocompatibility. EPL and PBA modified GelMA hydrogel (Gel-EPL/B) showed stronger activity on chondrocytes compared to the GelMA control group. The Gel-EPL/B group induced the secretion of more extracellular matrix and improved the chondrogenic differentiation potential of stem cells. Finally, thus hydrogel promoted the tissue repair of cartilage defects. CONCLUSION: Modified hydrogel is effective in cartilage tissue repair.


Asunto(s)
Agrecanos/química , Agrecanos/farmacología , Gelatina/química , Hidrogeles/química , Cicatrización de Heridas/efectos de los fármacos , Adsorción , Animales , Cartílago Articular/patología , Diferenciación Celular , Condrocitos/citología , Condrocitos/efectos de los fármacos , Matriz Extracelular , Humanos , Masculino , Ratones , Polilisina , Polímeros , Ratas , Ratas Sprague-Dawley , Ingeniería de Tejidos/métodos
5.
Phys Chem Chem Phys ; 21(27): 15222-15232, 2019 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-31250877

RESUMEN

Star-shaped polymers have received significant attention and have been widely developed for prospective applications in drug delivery owing to their topological structure and unique physiochemical characteristics. The anticancer drug doxorubicin (DOX) was used as a model drug, and four/six-arm star-shaped block polymeric micelles were employed as the carriers. The dissipative particle dynamics (DPD) method was adopted to simulate the formation of micelles, the effects of the hydrophobic/hydrophilic block ratio on the micellar structure and drug-loading performance, the effect of the drug loading content on the micellar morphology, and the effect of the pH-sensitive block ratio on the drug release properties. Under neutral conditions (pH = 7.4), increasing the hydrophobic block ratio reduces the stability of the micelle structure but could improve its drug loading performance. Increasing the pH-sensitive block (DEAEMA) ratio is beneficial to the drug loading performance of the mikto-arm star-shaped polymeric micelles and is detrimental to the drug loading performance of the herto-arm star-shaped polymeric micelles. After comparing the structural changes, radial distribution function (RDF) and mean square displacement (MSD) of the polymeric micelles with different pH-sensitive block ratios under weakly acidic conditions (pH = 5.0), the drug release properties of the drug-loaded micelles were systematically analysed. The results showed that the higher the proportion of the pH-sensitive block in the polymeric micelles, the better their pH-response performance, and the looser the structure of the micelles during the release process. A too high or too low ratio of pH-sensitive blocks in the polymeric micelles was detrimental to drug release performance. This study could provide theoretical support for the structural design and development of novel functional block polymers.


Asunto(s)
Antineoplásicos/administración & dosificación , Doxorrubicina/administración & dosificación , Sistemas de Liberación de Medicamentos , Micelas , Simulación de Dinámica Molecular , Antineoplásicos/química , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/química , Doxorrubicina/química , Concentración de Iones de Hidrógeno , Polímeros/química
6.
Eur J Pharm Biopharm ; 196: 114181, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38224755

RESUMEN

Hyperpigmentation, a prevalent dermatological condition characterized by melanin overproduction, poses treatment challenges due to the hydrophilicity of alpha-arbutin, a widely utilized tyrosinase inhibitor. This study investigates the efficacy of dissolving microneedles (DMNs) in augmenting skin permeation for alpha-arbutin delivery to the targeted epidermal site. Porcine full-thickness skin was employed in a 24-hour Franz cell study, commencing with the assessment of commercial alpha-arbutin-containing products. Solid steel microneedles (CMNs) from Dermapen® were utilized as both pre- and post-treatment modalities to evaluate the influence of different applications on alpha-arbutin delivery. Additionally, alpha-arbutin-loaded polyvinylpyrrolidone-co-vinyl acetate (PVPVA) DMNs, containing 2 % w/w alpha-arbutin, were fabricated and examined for their permeation-enhancing capabilities. HPLC analysis and 3D Orbitrap Secondary Ion Mass Spectrometry (OrbiSIMS) were employed to quantify and visualize alpha-arbutin in various Franz cell components. Results indicate that alpha-arbutin permeation to the skin was restricted (less than 1 %) without microneedle application and significantly increased by 6-fold (4-5 %) with post-treatment CMNs and DMNs, but not with pre-treatment CMNs. Notably, DMNs exhibited a more sustainable and robust capacity than post-treatment CMNs. OrbiSIMS imaging analysis revealed that DMNs visually enhance skin permeation of alpha-arbutin by delivering the compound to the basal layer of the targeted skin location. Overall, this study underscores the potential of DMNs as a promising delivery system for promoting targeted intradermal delivery of alpha-arbutin, providing a comprehensive exploration of various methodologies to identify innovative and improved microneedle approaches for alpha-arbutin permeation.


Asunto(s)
Arbutina , Nevo Pigmentado , Neoplasias Cutáneas , Espectrometría de Masa de Ion Secundario , Porcinos , Animales , Administración Cutánea , Piel , Epidermis , Polímeros , Agujas , Sistemas de Liberación de Medicamentos/métodos
7.
Bioresour Technol ; 395: 130360, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38266786

RESUMEN

A novel suspended carrier was prepared by sticking activated carbon (AC) and magnetite (Fe3O4) onto polypropylene slices. Although this carrier could not reverse the decreased denitrification capacity trends under anoxic conditions at an influent carbon/nitrogen (C/N) ratio of 2, it enhanced denitrification by stimulating sludge reduction and accelerating electron transfer to certain extent. The carrier stuck by mixed AC/Fe3O4 exhibited better performance in terms of sludge reduction, extracellular polymeric substances (EPS) secretion, and denitrification than that merely stuck by AC and Fe3O4 at an influent C/N ratio of 2. The carrier stuck by mixed AC/Fe3O4 increased the total nitrogen removal efficiency by 24.6 % ± 12.5 % in a 72-h denitrification batch experiment compared to the common polypropylene carrier. Moreover, the carrier improved EPS secretion and nitrogen metabolism and promoted the growth of Trichococcus and some denitrifying genera. This study provides a reference for the treatment of low C/N ratio sewage.


Asunto(s)
Desnitrificación , Aguas del Alcantarillado , Óxido Ferrosoférrico , Carbón Orgánico , Nitrógeno , Polipropilenos , Reactores Biológicos
8.
Arch Oral Biol ; 166: 106046, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38991331

RESUMEN

OBJECTIVES: This study aims to investigate and predict the therapeutic agents associated with disulfidptosis in periodontitis. DESIGN: The dataset GSE10334 was downloaded from the Gene Expression Omnibus (GEO) database and used to train a least absolute shrinkage and selection operator (LASSO) regression and support vector machine recursive feature elimination (SVM-RFE) algorithm to identify genes associated with disulfidptosis in periodontitis. GSE16134 validation sets, polymerase chain reaction (PCR), and gingival immunofluorescence were used to verify the results.Single-gene Gene Set Enrichment Analysis (GSEA) was performed to explore the potential mechanisms and functions of the characterized genes. Immune infiltration and correlation analyses were performed, and competing endogenous RNA (ceRNA) networks were constructed. Effective therapeutic drugs were then predicted using the DGIdb database, and molecular docking was used to validate binding affinity. RESULTS: Six genes (SLC7A11, SLC3A2, RPN1, NCKAP1, LRPPRC, and NDUFS1) associated with disulfidptosis in periodontitis were obtained. Validation results from external datasets and experiments were consistent with the screening results. Single-gene GSEA analysis was mainly enriched for antigen presentation and immune-related pathways and functions.Immune infiltration and correlation analyses revealed significant regulatory relationships between these genes and plasma cells, resting dendritic cell, and activated NK cells. The ceRNA network was visualized. And ME-344, NV-128, and RILUZOLE, which have good affinity to target genes, were identified as promising agents for the treatment of periodontitis. CONCLUSIONS: SLC7A11, SLC3A2, RPN1, NCKAP1, LRPPRC, and NDUFS1 are targets associated with disulfidptosis in periodontitis, and ME-344, NV-128, and RILUZOLE are promising agents for the treatment of periodontitis.


Asunto(s)
Periodontitis , Humanos , Periodontitis/genética , Simulación del Acoplamiento Molecular , Máquina de Vectores de Soporte , Bases de Datos Genéticas , Algoritmos , Relevancia Clínica
9.
J Dent ; 143: 104899, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38428719

RESUMEN

OBJECTIVES: Demineralized bone matrix (DBM) is a well-established bone graft material widely accepted by dentists and the public for its favorable osteoconductivity and osteoinductive potential. This article aimed to provide a narrative review of the current therapeutic applications and limitations of DBM in maxillofacial bone defects. STUDY SELECTION, DATA, AND SOURCES: Randomized controlled trials, prospective or retrospective clinical studies, case series and reports, and systematic reviews. MEDLINE, PubMed, and Google Scholar were searched using keywords. CONCLUSIONS: Some evidence supported the therapeutic application of DBM in periodontal intrabony defects, maxillary sinus lifts, ridge preservation, ridge augmentation, alveolar cleft repair, orthognathic surgery, and other regional maxillofacial bone defects. However, the limitations of DBM should be considered when using it, including potential low immunogenicity, instability of osteoinductive potential, handling of the graft material, and patient acceptance. CLINICAL SIGNIFICANCE: With the increasing demand for the treatment of maxillofacial bone defects, DBM is likely to play a greater role as a promising bone graft material. Safe and effective combination treatment strategies and how to maintain a stable osteoinductive potential will be the future challenges of DBM research.


Asunto(s)
Matriz Ósea , Regeneración Ósea , Humanos , Matriz Ósea/trasplante , Estudios Prospectivos , Estudios Retrospectivos , Resultado del Tratamiento , Trasplante Óseo
10.
J Hazard Mater ; 458: 131999, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37459762

RESUMEN

Nanoplastics (NPs) and microplastics (MPs) could act as potential carriers for pharmaceuticals and personal care products (PPCPs) and alter the bioavailability in the aquatic environment. The effects of NPs and MPs of polystyrene (PS) and polyethylene (PE) on the availability of five PPCPs including carbamazepine, bisphenol A, estrone, triclocarban and 4-tert-octylphenol were investigated by negligible depletion solid- phase microextraction (nd-SPME). The freely dissolved concentrations of PPCPs decreased with the increasing concentrations of NPs/MPs. The overall order of the sorption coefficients (logKNP / logKMP) of PPCPs was as follows: 100 nm PS > 50 nm PS > 1 µm PS > 100 µm PS > 100 µm PE. Sorption of PPCPs by NPs was generally 1-2 orders of magnitude stronger than to MPs. The log KNP / log KMP values (3.16-5.21) increased with the log KOW (2.45-5.28) of PPCPs, however, linear correlation was only observed between log KMP and log KOW. The particle size, specific surface area, aggregation state as well as hydrophobicity played an important role in the sorption. Coexistence of fulic acid (FA) with NPs inhibited the sorption due to the fouling of FA on NPs. This study suggests that sorption of PPCPs to MPs/NPs could reduce bioavailability of PPCPs in the aquatic environment.


Asunto(s)
Cosméticos , Contaminantes Químicos del Agua , Microplásticos , Plásticos , Contaminantes Químicos del Agua/análisis , Poliestirenos , Polietileno , Preparaciones Farmacéuticas
11.
Sci Total Environ ; 824: 153790, 2022 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-35150683

RESUMEN

Mechanical vibrations and solar energy are ubiquitous in the environment. Hereon, we report the synergic enhancement of the oxidation by simultaneously harvesting solar and mechanical vibrations through flexible piezo and photocatalytic composite nanofiber mats. Surface enriched titanium dioxide nanoparticles incorporated in polyacrylonitrile (PAN/TiO2) nanofibers were synthesized using a single pot electrospinning process with well-defined fiber diameters with widely tunable loading density. By incorporating photocatalytic TiO2 in flexible piezoelectric PAN nanofiber support, piezoelectric fields generated under the mechanical deformation promote the separation of the photogenerated electrons and holes to accelerate oxidation of pollutants. Our results demonstrated that the catalytic activity of PAN/TiO2 nanofibers in photodegradation of Rhodamine B (RhB) can be greatly enhanced by environmental vibration-induced piezoelectricity of PAN nanofibers, with a maximum enhancement factor of ~2.5. The working mechanism for the enhanced photocatalytic activity of PAN/TiO2 nanofibers by the mechanical vibrations were attributed to the piezoelectric effect of PAN nanofibers, which could efficiently promote the separation of the photogenerated electrons and holes in the TiO2 nanoparticles. We believe the approach to enhancing the catalytic activity of mat can make full use of the polymer properties and natural energy, and it also can be extended to other composite polymer/semiconductor systems.


Asunto(s)
Restauración y Remediación Ambiental , Nanofibras , Catálisis , Polímeros , Titanio
12.
Int J Biol Macromol ; 220: 267-279, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-35985394

RESUMEN

In order to solve the problems of poor mechanical property, non-antibacterial and low flux of calcium alginate (CaAlg) membrane, silver nanoparticles (AgNPs) were synthesized with bovine serum albumin (BSA) and carboxymethyl chitosan (CMCS) for improving CaAlg membrane in this paper. Meanwhile, the dispersion property of silver nanoparticles and the mechanical property, thermal stability, antibacterial property and filtration efficiency of the composite membrane were explored. The results illustrated CMCS observably strengthened the mechanical property and thermal stability of the composite membrane, and AgNPs endowed the composite membrane with excellent antibacterial property. The flux of the BSA/CMCS/AgNPs/CaAlg composite membrane was raised compared to CaAlg membrane. Finally, the viscose fiber/polyethylene terephthalate fiber (VF-PET) nonwoven fabric was introduced as the support layer to further improve the filtration flux and mechanical property of the composite membrane. VF-PET/BSA/CMCS/AgNPs/CaAlg membrane had a rejection rate of over 99.0 % for dye molecules and <9.0 % for salt ions, while the flux maintained 38.5 L·m-2·h-1. Furthermore, VF-PET/BSA/CMCS/AgNPs/CaAlg membrane also had excellent separation effect on actual dye wastewater. The separation of dye and salt by the membrane mainly depended on the screening mechanism of membrane pore size, rather than adsorption. The composite membrane had an outstanding performance on the separation of dye molecules and inorganic salt ions.


Asunto(s)
Quitosano , Nanopartículas del Metal , Alginatos , Antibacterianos/farmacología , Hidrogeles , Tereftalatos Polietilenos , Albúmina Sérica Bovina , Plata , Aguas Residuales
13.
Macromol Rapid Commun ; 32(1): 94-9, 2011 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-21432976

RESUMEN

Greatly enhanced energy density in poly(vinylidene fluoride-chlorotrifluoroethylene) [P(VDF-CTFE)] is realized through interface effects induced by a photo cross-linking method. Being different from nanocomposites with lowered dielectric strength, the cross-linked P(VDF-CTFE)s possess a high breakdown field as well as remarkably elevated polarization, both of which contribute to the enhanced energy density as high as 22.5 J · cm(-3). Moreover, patterned thin films with various shapes and sizes are fabricated by photolithography, which sheds new light on the integration of PVDF-based electroactive polymers into organic microelectronic devices such as flexible pyroelectric/piezoelectric sensor arrays or non-volatile ferroelectric memory devices.


Asunto(s)
Clorofluorocarburos/química , Reactivos de Enlaces Cruzados/química , Polímeros/química , Polivinilos/química , Rastreo Diferencial de Calorimetría , Transferencia de Energía , Procesos Fotoquímicos , Temperatura , Termodinámica
14.
Water Res ; 170: 115290, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31770647

RESUMEN

Microplastics (MPs) discharged into the natural environment undergo various wearthering pathways, such as mechanical abrasion and ultraviolet (UV) irradiation. However, little is known about the effects of such aged MPs on the bioavailability of hydrophobic organic compounds (HOCs) in aqueous environments. To simulate the natural oxidation and UV-ageing process of MPs, three kinds of modified polyethylene MPs were obtained by plastic etching processes common in industry and UV irradiation, namely, etched MPs (EMPs), UV-aged MPs (UV-MPs), and etched MPs followed by UV ageing (UV-EMPs). The modified MPs showed a higher content of surface oxygen-containing groups than the pristine MPs, and the specific surface area and pore volume increased significantly after etching and ultraviolet ageing, especially for the EMPs (1.67 m2 g-1 and 0.0049 cm³ g-1) and UV-EMPs (2.37 m2 g-1 and 0.0089 cm³ g-1). The effect of modified MPs on the availability of 10 polycyclic aromatic hydrocarbons (PAHs, logKow 4.18-6.20) was evaluated by negligible-depletion solid-phase microextraction (nd-SPME). The free concentrations (Cfree) of most PAHs (except for less hydrophobic PAHs, logKow 4.18 and 4.56) decreased with an increasing concentration of MPs. The logarithms of the sorption coefficients of PAHs with various MPs (logKMPs, logKUV-MPs, logKEMPs and logKUV-EMPs) were linearly correlated with logKow, suggesting that the sorption is hydrophobicity dependent. Compared with the results for pristine MPs (logKMP 3.80-4.95), UV ageing only slightly enhanced the sorption of PAHs by MPs (logKUV-MPs 3.71-4.98), whereas the plastic etching processes significantly enhanced sorption (logKEMPs 3.85-5.18 and logKUV-EMPs 3.90-5.28). The sorption of PAHs to MPs is mainly based on partitioning; however, a mechanism of adsorption also likely takes place in EMPs and UV-EMPs due to hydrogen bonding and π-π interactions. Desorption study indicated that PAH desorption from MPs are dominated by film diffusion. However, intraparticle diffusion also takes great part for the EMPs. These results suggest that modification of MPs in the natural environment will change the availability of HOCs.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Adsorción , Microplásticos , Plásticos
15.
Int J Biol Macromol ; 156: 362-371, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32298721

RESUMEN

A plant derived bio-macromolecule namely lignin (L) and a green phosphorus compound like phytic acid (PA) were functionalized with graphene oxide (GO) and subsequently, used to enhance the flame retardant properties of polyamide 66 (PA66) fabrics in a one pot deposition method. Meanwhile, we also considered pure phytic acid and one more bio-derived charring agent like chitosan (CS) to formulate a series of GO-based flame retardant finishing by altering the applied compounds in the formulation. The applied finishing with a minimum loading % (i.e., less than 10%) rarely altered the physical properties (i.e., color, handle and tensile strength, etc.) of treated textiles while provided enhanced thermal stability and added flame retardancy. Thus, a significant increase in limiting oxygen index (LOI) by 27% was received for the GO-lignin and GO-phytic acid modified fabric sample (i.e., PA66-A), indicating the supremacy of graphene-based compound. Furthermore, a substantial reduction in the peak heat release rate (pHRR) by 25% was also noticed for the fabric sample treated with GO-lignin, chitosan and phytic acid (i.e., PA66-D). Additionally, the as prepared finishing exhibited a considerable level of wash durability as a maximum reduction of pHRR by 17% was retained even after 5 washing cycles.


Asunto(s)
Retardadores de Llama/análisis , Grafito/química , Nylons/química , Fenómenos Físicos , Lignina/química , Fenómenos Mecánicos , Estructura Molecular , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Termogravimetría , Difracción de Rayos X
16.
Environ Pollut ; 249: 91-98, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30884397

RESUMEN

The Tibet Plateau, the so-called Third Pole of the world, is home to the headstreams of many great rivers. The levels of microplastic pollution in those rivers, however, are unknown. In this study, surface water and sediment samples were collected from six sampling sites along five different rivers. The surface water and sediment samples were collected with a large flow sampler and a stainless steel shovel, respectively. The abundance of microplastics ranged from 483 to 967 items/m3 in the surface water and from 50 to 195 items/kg in the sediment. A large amount of small, fibrous, transparent microplastics were found in this study. Five types of microplastics with different chemical compositions were identified using micro-Raman spectroscopy: polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyamide (PA). These results demonstrate that rivers in the Tibet Plateau have been contaminated by microplastics, not only in developed areas with intense human activity but also in remote areas, where microplastic pollution requires further attention.


Asunto(s)
Monitoreo del Ambiente , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Contaminación Ambiental , Polietileno/análisis , Polipropilenos/análisis , Poliestirenos , Ríos/química , Espectrometría Raman , Tibet , Agua
17.
Semin Ophthalmol ; 32(5): 607-613, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27367270

RESUMEN

PURPOSE: To evaluate the safety, efficacy, and outcomes of early bicanalicular silicone intubation in the treatment of acute purulent dacryocystitis. METHODS: This prospective interventional case series focused on acute purulent dacryocystitis from February 2010 to March 2014. Of the 21 cases, 16 cases were treated at the Fujian Provincial Hospital, and five cases were treated at the Lianjiang Hospital. Bicanalicular silicone intubation was inserted in the original lacrimal duct within 10 days after abscess decompression by pus aspiration method and systemic antibiotic application. Data collection included demographic profiles, perioperative and postoperative complications, and revision surgery. Resolution of signs and symptoms of acute purulent dacryocystitis, as well as successful anatomical patency assessed by irrigation, was evaluated. Follow-up times were more than 12 months, and ranged from 14 to 63 months. RESULTS: All patients showed remarkable improvement of pain and swelling within 48 hours. Resolution of the erythema and edema was observed within one week after bicanalicular silicone intubation combined with topical antibiotic lavage. No intraoperative and postoperative complications were observed. After initial bicanalicular silicone intubation, anatomical success was observed in 66.7% (14/21) of the patients. Of the remaining seven patients who presented with severe reflux in irrigation, two patients chose re-intubation and five patients underwent standard external dacryocystorhinostomy. All patients had anatomical success at last follow-up. CONCLUSION: Early bicanalicular silicone intubation appears to be a safe, effective, and simple procedure, which offers a reasonable option in the treatment of acute purulent dacryocystitis, especially for those developing and underdeveloped areas.


Asunto(s)
Dacriocistitis/cirugía , Dacriocistorrinostomía/métodos , Intubación/métodos , Conducto Nasolagrimal/cirugía , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Prospectivos , Siliconas
18.
Nanoscale ; 6(19): 11219-25, 2014 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-25126952

RESUMEN

Single- or few-layered transitional metal dichalcogenides, as a new genus of two-dimensional nanomaterials, have attracted tremendous attention in recent years, owing to their various intriguing properties. In this study, chemically exfoliated MoS2 nanosheets are modified with lipoic acid-terminated polyethylene glycol (LA-PEG), obtaining PEGylated MoS2 (MoS2-PEG) with high stability in physiological solutions and no obvious toxicity. Taking advantage of its ultra-high surface area, the obtained MoS2-PEG is able to load a photodynamic agent, chlorin e6 (Ce6), by physical adsorption. In vitro experiments reveal that Ce6 after being loaded on MoS2-PEG shows remarkably increased cellular uptake and thus significantly enhanced photodynamic therapeutic efficiency. Utilizing the strong, near-infrared (NIR) absorbance of the MoS2 nanosheets, we further demonstrate photothermally enhanced photodynamic therapy using Ce6-loaded MoS2-PEG for synergistic cancer killing, in both in vitro cellular and in vivo animal experiments. Our study presents a new type of multifunctional nanocarrier for the delivery of photodynamic therapy, which, if combined with photothermal therapy, appears to be an effective therapeutic approach for cancer treatment.


Asunto(s)
Disulfuros/uso terapéutico , Nanopartículas del Metal/uso terapéutico , Molibdeno/uso terapéutico , Nanocápsulas/química , Neoplasias Experimentales/terapia , Fotoquimioterapia/métodos , Polietilenglicoles/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Clorofilidas , Materiales Biocompatibles Revestidos/síntesis química , Terapia Combinada/métodos , Difusión , Disulfuros/química , Humanos , Luz , Nanopartículas del Metal/química , Molibdeno/química , Nanocápsulas/administración & dosificación , Nanocápsulas/ultraestructura , Neoplasias Experimentales/patología , Fármacos Fotosensibilizantes/administración & dosificación , Fármacos Fotosensibilizantes/química , Fototerapia/métodos , Porfirinas/administración & dosificación , Porfirinas/química , Resultado del Tratamiento
19.
Biomaterials ; 34(36): 9160-70, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24008045

RESUMEN

Magnetic targeting that utilizes a magnetic field to specifically delivery theranostic agents to targeted tumor regions can greatly improve the cancer treatment efficiency. Herein, we load chlorin e6 (Ce6), a widely used PS molecule in PDT, on polyethylene glycol (PEG) functionalized iron oxide nanoclusters (IONCs), obtaining IONC-PEG-Ce6 as a theranostic agent for dual-mode imaging guided and magnetic-targeting enhanced in vivo PDT. Interestingly, after being loaded on PEGylated IONCs, the absorbance/excitation peak of Ce6 shows an obvious red-shift from ~650 nm to ~700 nm, which locates in the NIR region with improved tissue penetration. Without noticeable dark toxicity, Ce6 loaded IONC-PEG (IONC-PEG-Ce6) exhibits significantly accelerated cellular uptake compared with free Ce6, and thus offers greatly improved in vitro photodynamic cancer cell killing efficiency under a low-power light exposure. After demonstrating the magnetic field (MF) enhanced PDT using IONC-PEG-Ce6, we then further test this concept in animal experiments. Owing to the strong magnetism of IONCs and the long blood-circulation time offered by the condensed PEG coating, IONC-PEG-Ce6 shows strong MF-induced tumor homing ability, as evidenced by in vivo dual modal optical and magnetic resonance (MR) imaging. In vivo PDT experiment based magnetic tumor targeting using IONC-PEG-Ce6 is finally carried out, achieving high therapeutic efficacy with dramatically delayed tumor growth after just a single injection and the MF-enhanced photodynamic treatment. Considering the biodegradability and non-toxicity of iron oxide, our IONC-PEG-Ce6 presented in this work may be a useful multifunctional agent promising in photodynamic cancer treatment under magnetic targeting.


Asunto(s)
Compuestos Férricos/química , Rayos Infrarrojos , Nanopartículas/química , Fotoquimioterapia , Polietilenglicoles/química , Porfirinas/farmacología , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Clorofilidas , Endocitosis/efectos de los fármacos , Compuestos Férricos/síntesis química , Humanos , Ratones , Ratones Endogámicos BALB C , Células 3T3 NIH , Nanopartículas/ultraestructura , Polietilenglicoles/síntesis química , Porfirinas/síntesis química , Porfirinas/química
20.
ACS Nano ; 7(8): 6782-95, 2013 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-23822176

RESUMEN

Multifunctional nanoplatforms that are safe and have multiple therapeutic functions together with imaging capabilities are highly demanded in the development of new cancer theranostic approaches. A number of near-infrared (NIR)-absorbing inorganic nanomaterials, although having shown great promise not only to photothermally ablate tumors but also to enhance the efficacy of other types of therapies, are not biodegradable and would be retained in the body for a long time. Herein, we develop a multifunctional nanocomposite by coating magnetic iron oxide nanoclusters with a near-infrared light-absorbing polymer polypyrrole (PPy), obtaining Fe3O4@PPy core-shell nanoparticles, which after functionalization with polyethylene glycol could be used for imaging-guided, remotely controlled cancer combination therapy. In this system, the Fe3O4 core, which could be gradually decomposed in physiological environments, is useful for magnetically controlled drug delivery as well as a magnetic resonance imaging contrast. The PPy shell, as an organic polymer, is able to load therapeutic molecules with aromatic structures and also exhibits a strong photothermal effect, which can be used to enhance the chemotherapeutic efficacy, showing an outstanding in vivo synergistic antitumor effect. Our work encourages further exploration of light-absorbing polymer-based nanocomposites for cancer combination therapy under remote physical controls.


Asunto(s)
Antineoplásicos/administración & dosificación , Portadores de Fármacos/química , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Polímeros/química , Pirroles/química , Animales , Materiales Biocompatibles/química , Línea Celular Tumoral , Femenino , Compuestos Férricos/química , Humanos , Imagen por Resonancia Magnética , Magnetismo , Ratones , Ratones Endogámicos BALB C , Microscopía Electrónica de Transmisión , Nanocompuestos/química , Nanotecnología/métodos , Trasplante de Neoplasias , Polietilenglicoles/química
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