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1.
Environ Sci Technol ; 56(17): 12257-12266, 2022 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-35960262

RESUMEN

Massive microplastics are deposited in the coastal zone. Tire particles (TPs) are an important microplastic source, but little is known about how TPs affect the microbial community composition and function in coastal sediments and the role leachable additives play in TP toxicity. Here, a microcosm experiment was performed using coastal sediments amended with different doses of TPs and with their leachable additives to investigate their effects on the sediment microbial community composition and function. Environmentally relevant concentrations of TPs can change the microbial community structure, decrease community diversity, and inhibit nutrient cycling processes, including carbon fixation and degradation, nitrification, denitrification, and sulfur cycling in sediments. Notably, the raw TP and leachate treatments showed consistent effects. A variety of additives were found in the pore water of sediment, and they could explain over 90% of the variations of the community structure. Further modeling revealed that leachable additives not only directly influenced community function but also indirectly affected community diversity and function by shifting the community structure. In addition, rare taxa could be crucial mediators of ecological functions of sediment microbial community. Combined, this study provides novel insights into the role of TPs' leachable additives in affecting sediment microbial community and function.


Asunto(s)
Sedimentos Geológicos , Microbiota , Sedimentos Geológicos/química , Microplásticos , Nitrificación , Plásticos/farmacología
2.
Molecules ; 27(9)2022 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-35566251

RESUMEN

Hydrogels are crosslinked polymer chains with three-dimensional (3D) network structures, which can absorb relatively large amounts of fluid. Because of the high water content, soft structure, and porosity of hydrogels, they closely resemble living tissues. Research in recent years shows that hydrogels have been applied in various fields, such as agriculture, biomaterials, the food industry, drug delivery, tissue engineering, and regenerative medicine. Along with the underlying technology improvements of hydrogel development, hydrogels can be expected to be applied in more fields. Although not all hydrogels have good biodegradability and biocompatibility, such as synthetic hydrogels (polyvinyl alcohol, polyacrylamide, polyethylene glycol hydrogels, etc.), their biodegradability and biocompatibility can be adjusted by modification of their functional group or incorporation of natural polymers. Hence, scientists are still interested in the biomedical applications of hydrogels due to their creative adjustability for different uses. In this review, we first introduce the basic information of hydrogels, such as structure, classification, and synthesis. Then, we further describe the recent applications of hydrogels in 3D cell cultures, drug delivery, wound dressing, and tissue engineering.


Asunto(s)
Hidrogeles , Ingeniería de Tejidos , Materiales Biocompatibles/química , Sistemas de Liberación de Medicamentos , Hidrogeles/química , Hidrogeles/uso terapéutico , Polímeros/química
3.
Adv Exp Med Biol ; 1250: 125-140, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32601942

RESUMEN

In the tissue engineering research field, nanobiomaterials highlight the impact of novel bioactive materials in both current applications and their potentials in future progress for tissue engineering and regenerative medicine. Tissue engineering is a well-investigated and challenging biomedical field, with promising perspectives to improve and support quality of life for the patient. To assess the response of those extracellular matrices (ECMs), induced by biomedical materials, this review will focus on cell response to natural biomaterials for biocompatibility.


Asunto(s)
Materiales Biocompatibles , Ingeniería de Tejidos , Materiales Biocompatibles/normas , Células/inmunología , Matriz Extracelular/inmunología , Humanos , Calidad de Vida , Medicina Regenerativa , Ingeniería de Tejidos/métodos
4.
Protein Expr Purif ; 126: 9-15, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27189822

RESUMEN

Targeting recombinant proteins at highly extracellular production in the culture medium of Escherichia coli presents a significant advantage over cytoplasmic or periplasmic expression. In this work, a recombinant protein between ZZ protein and alkaline phosphatase (rZZ-AP) was constructed. Because rZZ-AP has the IgG-binding capacity and enzymatic activity, it can serve as an immunoreagent in immunoassays. However, only a very small portion of rZZ-AP is generally secreted into the aqueous medium under conventional cultivation procedure. Hence, we emphasized on the optimization of the culture procedures and attempted to dramatically enhance the yield of extracellular rZZ-AP from E. coli HB101 host cells by adding sucrose, glycine, and Triton X-100 in the culture medium. Results showed that the extracellular production of rZZ-AP in the culture medium containing 5% sucrose, 1% glycine, and 1% Triton X-100 was 18.6 mg/l, which was 18.6-fold higher than that without the three chemicals. And the ß-galactosidase activity test showed that the increased extracellular rZZ-AP was not due to cell lysis. Further analysis suggested a significant interaction effect among the three chemicals for the enhancement of extracellular production. Ultrastructural analysis indicated that the enhancement may be due to the influence of sucrose, glycine, and Triton X-100 on the periplasmic osmolality, permeability, or integrity of the cell wall, respectively. This proposed approach presents a simple strategy to enhance the extracellular secretion of recombinant proteins in the E. coli system at the process of cell cultivation.


Asunto(s)
Fosfatasa Alcalina/biosíntesis , Escherichia coli/metabolismo , Expresión Génica , Glicina/farmacología , Octoxinol/farmacología , Periplasma/metabolismo , Sacarosa/farmacología , Fosfatasa Alcalina/genética , Escherichia coli/genética , Periplasma/genética , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/genética
5.
AJR Am J Roentgenol ; 204(4): W429-38, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25794092

RESUMEN

OBJECTIVE: The purpose of this study was to determine whether the occurrence of numerous colonic bubbles during CT colonography (CTC) performed with polyethylene glycol cleansing and oral iohexol fecal/fluid tagging could be prevented by use of simethicone. SUBJECTS AND METHODS: Adults with suspected colonic neoplasia who had been randomly assigned to control and simethicone intervention groups underwent CTC after cleansing with 4 L of polyethylene glycol, tagging with 50 mL of 350 mg I/mL oral iohexol, and without (control) or with (intervention) oral administration of 200 mg of simethicone. Colonic segments in the control and intervention groups were evaluated for amount of colonic bubbles during CTC. A 6-point grading system was used in which 0 indicated no bubbles and 5 indicated that more than three fourths of the air-distended mucosa was covered with bubbles. The primary endpoint was a per-patient colonic bubble grade, derived as an average of the segmental grades. RESULTS: Eighty adults with suspected colonic neoplasia were randomly assigned to the control (40 patients) and simethicone intervention (40 patients) groups. A total of 659 colonic segments in the control group and 689 segments in the intervention group were evaluated for amount of colonic bubbles during CTC. The per-patient colonic bubble score was significantly lower in the simethicone intervention group than in the control group. The mean score was 0.0±0.1 (SD) versus 1.2±0.8 (p<0.001; 95% CI for the mean difference, -1.4 to -1.0). In the intervention group, 673 (97.7%) segments were grade 0, and 16 (2.3%) were grade 1. In contrast, in the control group, 226 (34.3%) segments were grade 0; 173 (26.3%), grade 1; 175 (26.6%), grade 2; 45 (6.8%), grade 3; 23 (3.5%), grade 4; and 17 (2.6%), grade 5. CONCLUSION: The colonic bubbles associated with fecal/fluid tagging with iohexol can be successfully prevented by adding simethicone to the colonic preparation.


Asunto(s)
Antiespumantes/farmacología , Neoplasias del Colon/diagnóstico por imagen , Colonografía Tomográfica Computarizada , Medios de Contraste/farmacología , Yohexol/farmacología , Polietilenglicoles/farmacología , Simeticona/farmacología , Administración Oral , Adulto , Anciano , Colonoscopía , Medios de Contraste/administración & dosificación , Femenino , Humanos , Yohexol/administración & dosificación , Masculino , Persona de Mediana Edad , Polietilenglicoles/administración & dosificación , Estudios Prospectivos , Simeticona/administración & dosificación , Irrigación Terapéutica/métodos
6.
Phys Chem Chem Phys ; 17(1): 145-50, 2015 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-25407765

RESUMEN

Here we report that magnetic Ni/C catalysts with hierarchical structure can be fabricated from a mixture of nickel acetate, polyethylene glycol-200 and furfural by a one-step hydrothermal method, followed by calcination. It has been found that the calcination temperature is the key factor affecting the structure, morphology and the catalytic performance of the Ni/C catalysts. Of the as-made catalysts, the Ni/C sample calcined at 300 °C features small-size metallic Ni particles with high dispersion in the carbon matrix and a unique hierarchical structure, and has the highest rate of conversion of o-chloronitrobenzene with high selectivity to o-chloroanilines. The concerned Ni/C catalysts are magnetic due to the presence of metallic Ni particles, which makes their recovery easy after the reaction by an external magnetic field. The recovered Ni/C catalysts can be recycled at least ten times without obvious loss both in Ni loading and the catalytic performance. This kind of catalyst is also active for the selective hydrogenation of other nitroarenes to the corresponding anilines.


Asunto(s)
Carbono/química , Níquel/química , Acetatos/química , Compuestos de Anilina/química , Catálisis , Furaldehído/química , Hidrogenación , Campos Magnéticos , Nitrobencenos/química , Polietilenglicoles/química
7.
Int J Mol Sci ; 16(1): 1657-76, 2015 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-25588218

RESUMEN

Silk fibroin (SF) is a protein with bulky hydrophobic domains and can be easily purified as sericin-free silk-based biomaterial. Silk fibroin modified chitosan nanoparticle (SF-CSNP), a biocompatible material, has been widely used as a potential drug delivery system. Our current investigation studied the bio-effects of the SF-CSNP uptake by liver cells. In this experiment, the characterizations of SF-CSNPs were measured by particle size analysis and protein assay. The average size of the SF-CSNP was 311.9 ± 10.7 nm, and the average zeta potential was +13.33 ± 0.3 mV. The SF coating on the SF-CSNP was 6.27 ± 0.17 µg/mL. Moreover, using proteomic approaches, several proteins involved in the ubiquitin proteasome pathway were identified by analysis of differential protein expressions of HepG2 cell uptake the SF-CSNP. Our experimental results have demonstrated that the SF-CSNP may be involved in liver cancer cell survival and proliferation.


Asunto(s)
Quitosano/metabolismo , Portadores de Fármacos/metabolismo , Fibroínas/metabolismo , Nanopartículas/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Ubiquitina/metabolismo , Materiales Biocompatibles/metabolismo , Línea Celular , Células Hep G2 , Humanos , Proteómica , Transducción de Señal
8.
J Agric Food Chem ; 72(21): 12146-12155, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38747516

RESUMEN

In this study, an α-amylase-responsive controlled-release formulation was developed by capping polydopamine onto ß-cyclodextrin-modified abamectin-loaded hollow mesoporous silica nanoparticles. The prepared Aba@HMS@CD@PDA were subjected to characterization using various analytical techniques. The findings revealed that Aba@HMS@CD@PDA, featuring a loading rate of 18.8 wt %, displayed noteworthy release behavior of abamectin in the presence of α-amylase. In comparison to abamectin EC, Aba@HMS@CD@PDA displayed a significantly foliar affinity and improved rainfastness on lotus leaves. The results of field trail demonstrated a significantly higher control efficacy against Spodoptera litura Fabricius compared to abamectin EC at all concentrations after 7, 14, and 21 days of spaying, showcasing the remarkable persistence of Aba@HMS@CD@PDA. These results underscore the potential of Aba@HMS@CD@PDA as a novel and persistently effective strategy for sustainable on-demand crop protection. The application of nanopesticides can enhance the effectiveness and efficiency of pesticide utilization, contributing to more sustainable agricultural practices.


Asunto(s)
Protección de Cultivos , Insecticidas , Nanopartículas , Spodoptera , alfa-Amilasas , Animales , alfa-Amilasas/química , alfa-Amilasas/metabolismo , alfa-Amilasas/antagonistas & inhibidores , Nanopartículas/química , Protección de Cultivos/métodos , Spodoptera/efectos de los fármacos , Insecticidas/química , Insecticidas/farmacología , Ivermectina/análogos & derivados , Ivermectina/química , Ivermectina/farmacología , Polímeros/química , Dióxido de Silicio/química , Control de Insectos , Plaguicidas/química , Plaguicidas/farmacología , Indoles/química , Indoles/farmacología
9.
Environ Sci Technol ; 47(6): 2966-73, 2013 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-23398240

RESUMEN

Pressure-retarded osmosis (PRO) uses a semipermeable membrane to produce renewable energy from salinity-gradient energy. A spiral-wound (SW) design is one module configuration of the PRO membrane. The SW PRO membrane module has two different flow paths, axial and spiral, and two different spacers, net and tricot, for draw- and feed-solution streams, respectively. This study used an experimental approach to investigate the relationship between two interacting flow streams in a prototype SW PRO membrane module, and the adverse impact of a tricot fabric spacer (as a feed spacer) on the PRO performance, including water flux and power density. The presence of the tricot spacer inside the membrane envelope caused a pressure drop due to flow resistance and reduced osmotic water permeation due to the shadow effect. The dilution of the draw solution by water permeation resulted in the reduction of the osmotic pressure difference along a pressure vessel. For a 0.6 M NaCl solution and tap water, the water flux and corresponding maximum power density were 3.7 L m(-2)h(-1) and 1.0 W/m(2) respectively at a hydraulic pressure difference of 9.8 bar. The thickness and porosity of the tricot spacer should be optimized to achieve high SW PRO module performance.


Asunto(s)
Membranas Artificiales , Ósmosis , Energía Renovable , Salinidad , Cloruro de Sodio/química , Agua/química , Diseño de Equipo , Presión Osmótica , Permeabilidad , Porosidad , Presión
10.
Mol Biol Rep ; 40(2): 1979-86, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23160900

RESUMEN

Initially, we isolated the caffeic acid O-methyltransferase (COMT) gene from Miscanthus sinensis (accession number HM062766.1). Next, we produced transgenic tobacco plants with down-regulated COMT gene expression to study its control of total phenol and lignin content and to perform morphological analysis. These transgenic plants were found to have reduced PAL and ascorbate peroxidases expression, which are related to the phenylpropanoid pathway and antioxidant activity. The MsCOMT-down-regulated plants had decreased total lignin in the leaves and stem compared with control plants. Reduced flavonol concentrations were confirmed in MsCOMT-down-regulated transgenic plants. We also observed a morphological difference, with reduced plant cell number in transgenic plants harboring antisense MsCOMT. The transgenic tobacco plants with down-regulated COMT gene expression demonstrate that COMT plays a crucial role related to controlling lignin and phenol content in plants. Also, COMT activity may be related to flavonoid production in the plant lignin pathway.


Asunto(s)
Lignina/metabolismo , Metiltransferasas/genética , Nicotiana/genética , Fenol/metabolismo , Proteínas de Plantas/genética , Antioxidantes/metabolismo , Flavonoides/metabolismo , Expresión Génica , Regulación de la Expresión Génica de las Plantas , Ingeniería Genética , Redes y Vías Metabólicas , Metiltransferasas/biosíntesis , Mutagénesis Insercional , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Hojas de la Planta/ultraestructura , Proteínas de Plantas/biosíntesis , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Plantas Modificadas Genéticamente/ultraestructura , Poaceae/enzimología , Poaceae/genética , Nicotiana/metabolismo , Nicotiana/ultraestructura , Transcriptoma
11.
Water Res ; 237: 119992, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37099873

RESUMEN

Recent studies have reported conflicting results on the effects of biofouling on the adsorption behavior of microplastics (MPs). However, the underlying mechanisms driving the adsorption of MPs undergoing biofouling in aquatic environments remain unclear. This study examined the interactions between polyamide (PA), polyvinyl chloride (PVC) and polyethylene (PE) with two phytoplankton, namely cyanobacteria Microcystis aeruginosa and microalgae Chlorella vulgaris. Results indicated that MP effects on phytoplankton were dose- and crystalline-type dependent, with M. aeruginosa being more sensitive to MP exposure than C. vulgaris in the inhibitory order PA > PE > PVC. Analysis of antibiotic adsorption of the MPs showed significant contributions from CH/π interactions on PE and PVC and hydrogen bonding on PA, which decreased with phytoplankton biofouling and aging. Meanwhile, higher levels of extracellular polymeric substances on microalgae-aged MPs compared to cyanobacteria-aged MPs were conducive to adsorption of antibiotics, mainly through hydrophobic interactions. Overall, promotional and anti-promotional adsorption of antibiotics on MPs was induced by biofouling and aging of microalgae and cyanobacteria, respectively. This study provides deep insights into the specific mechanisms by which biofouling affects MP adsorption in aquatic environments, thus advancing our understanding of this critical environmental issue.


Asunto(s)
Incrustaciones Biológicas , Chlorella vulgaris , Cianobacterias , Microalgas , Contaminantes Químicos del Agua , Microplásticos , Fitoplancton , Plásticos/química , Antibacterianos/farmacología , Adsorción , Polietileno , Contaminantes Químicos del Agua/química
12.
Chemosphere ; 324: 138325, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36889472

RESUMEN

It is desirable but challenging to sense toxic nitrogen dioxide (NO2) for it has become one of the most prominent air pollutants. Zinc oxide-based gas sensors are known to detect NO2 gas efficiently, however, the sensing mechanism and involved intermediates structures remain underexplored. In the work, a series of sensitive materials, including zinc oxide (ZnO) and its composites ZnO/X [X = Cel (cellulose), CN (g-C3N4) and Gr (graphene)] have been comprehensively examined by density functional theory. It is found that ZnO favors adsorbing NO2 over ambient O2, and produces nitrate intermediates; and H2O is chemically held by zinc oxide, in line with the non-negligible impact of humidity on the sensitivity. Of the formed composites, ZnO/Gr exhibits the best NO2 gas-sensing performance, which is proved by the calculated thermodynamics and geometrical/electronic structures of reactants, intermediates and products. The interfacial interaction has been elaborated on for composites (ZnO/X) as well as their complexes (ZnO- and ZnO/X-adsorbates). The current study well explains experimental findings and opens up a way to design and unearth novel NO2 sensing materials.


Asunto(s)
Contaminantes Atmosféricos , Grafito , Óxido de Zinc , Óxido de Zinc/química , Grafito/química , Dióxido de Nitrógeno/análisis , Contaminantes Atmosféricos/análisis , Celulosa
13.
Polymers (Basel) ; 15(9)2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37177258

RESUMEN

The effects of alumina particle size and jet pressure on the bond strength of polyetheretherketone (PEEK) were examined to determine the airborne particle abrasion parameters with minimal effects on PEEK and to achieve optimal bond strength, as a reference for future clinical use. An alumina particle with four particle sizes and three jet pressures was used to air-abrade PEEK. Surface roughness (Ra), morphology, chemical structure, and wettability were analyzed using a stylus profilometer, scanning electron microscope, X-ray diffractometer, and contact angle analyzer, respectively. The shear bond strength (SBS) of PEEK and dental resin cement was analyzed using a universal testing machine (n = 10). The failure modes and debonded fracture surfaces were observed using optical microscopy. Airborne particle abrasion increased the Ra and hydrophobicity of PEEK and deposited alumina residues. The SBS generally decreased after thermal cycling. A large particle size damaged the PEEK surface. The effects of different particle sizes and jet pressures on the SBS were only significant in certain groups. Adhesive failure was the main mode for all groups. Within the limitations of this study, 110 µm grain-sized alumina particles combined with a jet pressure of 2 bar prevented damage to PEEK, providing sufficient SBS and bonding durability between PEEK and dental resin cement.

14.
Cytometry A ; 81(5): 400-8, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22311734

RESUMEN

We sought to determine the optimal Percoll concentration for ischemic rat brain prepared for flow cytometric (FC) measurements. Animals were subjected to the right middle cerebral artery (MCA) occlusion, and were euthanized at 3, 12, 24, and 72 h after reperfusion onset. The brains were processed by different concentrations (unisolated, 20, 25, 30, or 40%) of Percoll and stained with annexin V/propidium iodine (PI). Ischemic brain damage was evaluated by FC analysis and image analysis for histologic sections. The relative susceptibility of different phenotypes of cells to necrotic and apoptotic damage were evaluated by the FC analyses for the immunohistochemistry, PI, and the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL)-processed brain tissues. Our results showed that FC analysis effectively detected the extent and maturation of apoptotic/necrotic brain damage, and the results were consistent with those determined from histologic brain sections. Neuron was more vulnerable to apoptosis than glia, whereas both cellular phenotypes were compatible in susceptibility for necrotic cell death. Percoll at a low concentration (20%) could effectively remove tissue debris without affecting membranous integrity of the injured neurons. Conversely, high percentages of Percoll (30-40%) substantially increased membranous damage for the injured cells. These results supported the application of FC to determine the extent and progression in time, as well as relative phenotypes of apoptotic/necrotic cell deaths following ischemic damage. We highlighted the use of Percoll at low percentages to facilitate the removal of tissue debris and to improve membrane integrity preservation for the injured neurons.


Asunto(s)
Citometría de Flujo/métodos , Infarto de la Arteria Cerebral Media/patología , Neuroglía/patología , Neuronas/patología , Animales , Anexina A5/química , Apoptosis/fisiología , Modelos Animales de Enfermedad , Ataque Isquémico Transitorio/patología , Masculino , Necrosis , Neuroglía/metabolismo , Neuronas/metabolismo , Povidona/química , Propidio/química , Ratas , Ratas Sprague-Dawley , Dióxido de Silicio/química , Coloración y Etiquetado/métodos
15.
Environ Sci Technol ; 46(8): 4673-81, 2012 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-22420537

RESUMEN

This article analyzes the influence of feed channel spacers on the performance of pressure retarded osmosis (PRO). Unlike forward osmosis (FO), an important feature of PRO is the application of hydraulic pressure on the high salinity (draw solution) side to retard the permeating flow for energy conversion. We report the first observation of membrane deformation under the action of the high hydraulic pressure on the feed channel spacer and the resulting impact on membrane performance. Because of this observation, reverse osmosis and FO tests that are commonly used for measuring membrane transport properties (water and salt permeability coefficients, A and B, respectively) and the structural parameter (S) can no longer be considered appropriate for use in PRO analysis. To accurately predict the water flux as a function of applied hydraulic pressure difference and the resulting power density in PRO, we introduced a new experimental protocol that accounts for membrane deformation in a spacer-filled channel to determine the membrane properties (A, B, and S). PRO performance model predictions based on these determined A, B, and S values closely matched experimental data over a range of draw solution concentrations (0.5 to 2 M NaCl). We also showed that at high pressures feed spacers block the permeation of water through the membrane area in contact with the spacer, a phenomenon that we term the shadow effect, thereby reducing overall water flux. The implications of the results for power generation by PRO are evaluated and discussed.


Asunto(s)
Ósmosis , Centrales Eléctricas/instrumentación , Membranas Artificiales , Presión , Salinidad
16.
Eur Spine J ; 21(5): 971-9, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22160098

RESUMEN

PURPOSE: In the laminectomy model in rats, to verify anti-adhesive effectiveness of the new material, a mixture composed of poloxamer 407, calcium chloride, and xanthorrhizol, we compared it with that of commercially used solution form anti-adhesive agent GUARDIX-SL, Biorane. MATERIALS AND METHODS: A total of 108 Sprague-Dawley rats (SD rats) were divided equally into three groups: negative control group (NCG), positive control group (PCG), and experimental group (EG). After exposing the dura on L4 level, we closed the wound shortly after hemostasis, after administering the anti-adhesive agent. To evaluate effectiveness, 18 SD rats from each group were killed after 1 week of rearing. Nine were examined by grading of gross adhesion and the other nine, by grading of histological adhesion. The degree of adhesion in the remainder of 18 SD rats in each group was examined with the same method after four weeks of rearing. RESULTS: Comparing the degree of adhesion after growth for 1 week, the gross and histological adhesion of the EG was lower than that of the NCG. There was no statistical significance in the gross score (P = 0.63), but there was statistical significance in the histological score (P = 0.04). The EG showed similar or improved degrees of adhesion in comparison with the PCG. In comparison after growth for 4 weeks, although gross adhesion of the EG was not significantly lower than the NCG, histological adhesion was remarkably low in the EG (P = 0.01). The EG showed similar or improved degrees of gross and histological adhesion in comparison to that of the PCG. (P = 0.20, 0.07). CONCLUSION: The new anti-adhesive material showed similar or improved effectiveness with the existing agents for commercial use. This result suggests that the new anti-adhesive material will be a successful candidate as a future product for clinical use.


Asunto(s)
Laminectomía/métodos , Vértebras Lumbares/cirugía , Poloxámero/uso terapéutico , Adherencias Tisulares/prevención & control , Animales , Cloruro de Calcio , Modelos Animales , Fenoles , Ratas , Ratas Sprague-Dawley , Tensoactivos/uso terapéutico , Resultado del Tratamiento
17.
J Mater Sci Mater Med ; 23(12): 3067-73, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22968597

RESUMEN

The early adhesions of cells to various biopolymers are important to their growths and proliferations. Here, the adhesion of cells (e.g., fibroblasts) on the electrode of a quartz crystal microbalance (QCM) that was coated by PCL or PEG/PCL and further adsorbed by chitosan (CS) or CS/hyaluronic acid (HA) layers, was examined by cell-counting technique, QCM method and MTS assay under a serum-free condition for 3 h. The surfaces on electrodes of the QCM were confirmed to have been modified by measuring their contact angles, FT-IR spectra and the weights of biopolymers affected the frequency shifts of the QCM. Among tested surfaces on electrodes, the adhesion of fibroblasts on a HA/CS/PCL surface was the most (e.g., 3.08 × 10(5) cells/cm(2)) while that on a PEG/PCL surface was the least (e.g., 0.7 × 10(5) cells/cm(2)), as determined by cell-counting technique. The frequency shift and the mass of adhering fibroblasts on HA/CS/PCL electrodes were -3,537 ± 770 Hz and 3.78 ± 0.22 µg (n = 3), respectively, that were significantly exceeded those on other electrodes (-393 ± 58 Hz and 0.32 ± 0.06 µg, n = 3, respectively, for PEG/PCL electrodes). These results were consistent with cell-counting technique. Although MTS assay yielded similar results, it was less sensitive than the two aforementioned methods. In conclusion, modified electrodes of a QCM provide a convenient and sensitive method for examining the early adhesion of cells (e.g., 3 h) to biopolymer surfaces.


Asunto(s)
Poliésteres/química , Polisacáridos/química , Adsorción , Materiales Biocompatibles , Biopolímeros/análisis , Adhesión Celular , Células Cultivadas , Quitosano/química , Materiales Biocompatibles Revestidos/análisis , Materiales Biocompatibles Revestidos/química , Electrodos , Fibroblastos/citología , Fibroblastos/metabolismo , Humanos , Ácido Hialurónico/análisis , Polímeros/química , Tecnicas de Microbalanza del Cristal de Cuarzo
18.
Environ Int ; 166: 107382, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35803076

RESUMEN

The effects of microalgal biofouling on microplastic (MP) may differ from bacterial biofouling. In this study, the influence of microalgae on MP surface alteration, structural change, and adsorption of organic micropollutants was evaluated. Virgin polyethylene (PE), polyvinyl chloride (PVC), and polyamide (PA) were each immersed in algal photobioreactor and river freshwater for 30 days to simulate algal and river microbe biofouling respectively. Consequently, their physicochemical changes and adsorption potential of a mixture of six bisphenol analogues (BPA, BPS, BPE, BPB, BPF, BPAF) and two parabens (propyl-paraben, benzyl-paraben) were investigated. Owing to the algal bioactive compounds, major microalgae-induced biofouling and more MP aging than the river microbe aging were observed through fractures, pits, cracks, and algal attachments. Intrusion of algal organic matter and scission of polymeric functional groups were revealed during microalgal immersion and the potential MP aging pathways were proposed. Algal biofouling considerably altered the intrinsic properties of the MPs, consequently the adsorption capacity of PE and PVC was enhanced by 3.04-6.72 and 2.14-8.72 times, respectively. Adsorption process onto algal-aged MPs was pH-dependent, endothermic, non-spontaneous, and favored by hydrogen bonds. Meanwhile, the amide group in PA structure was conducive to organic micropollutant adsorption, which was likely reduced by algal aging and the erosion of the N-H stretching. Moreover, higher adsorption capacities of organic micropollutants were shown by the algal-biofilm PE and PVC than virgin and river microbial biofilm MPs. This study discloses that, biofouling and aging of MPs by microalgae through their bioactive components would engender more incidences on MP properties, organic micropollutants adsorption with associated environmental and health hazards.


Asunto(s)
Microalgas , Contaminantes Químicos del Agua , Microplásticos , Plásticos , Parabenos , Adsorción , Polietileno/farmacología , Contaminantes Químicos del Agua/farmacología
19.
Opt Express ; 19(9): 8291-6, 2011 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-21643079

RESUMEN

We propose a single mode transflective liquid crystal display (LCD) which is operated as the transmissive and reflective modes in a single pixel without dividing into sub-pixels. The single pixel transflective LCD was composed of the cross-polarized nematic LCD as a light modulator and the broadband cholesteric liquid crystal film (BCLCF) as a half mirror. The BCLCF, simply prepared by the exposure of ultraviolet light to the mixture of the nematic LC and the reactive mesogen with chirality, selectively reflects a certain circular polarization but transmits the orthogonal circular polarization in entire visible light. The electro-optical properties in both transmissive and reflective modes coincide with each other.


Asunto(s)
Presentación de Datos , Cristales Líquidos/química , Membranas Artificiales , Refractometría/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo
20.
AIDS Care ; 23(4): 508-14, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21271392

RESUMEN

Rapid oral fluid HIV testing (rapid oral testing) is in the process of being adapted in Taiwan and elsewhere given its advantages over prior HIV testing methods. To guide this process, we examined the acceptability of rapid oral testing at two time points (i.e., 1997 and 2007) among one of the highest risk populations, male injection drug users (IDUs). For this purpose, an anonymous self-administered survey was completed by HIV-negative IDUs involved in the criminal justice system in 1997 (N (1)=137 parolees) and 2007 (N (2)=106 prisoners). A social marketing model helped guide the design of our questionnaire to assess the acceptability of rapid oral testing. This included assessing a new product, across four marketing dimensions: product, price, promotion, and place. Results revealed that in both 1997 and 2007, over 90% indicated that rapid oral testing would be highly acceptable, particularly if the cost was under US$6, and that a pharmacy would be the most appropriate and accessible venue for selling the rapid oral testing kits. The vast majority of survey respondents believed that the cost of rapid oral testing should be federally subsidized and that television and newspaper advertisements would be the most effective media to advertise for rapid oral testing. Both the 1997 and 2007 surveys suggested that rapid oral HIV testing would be particularly accepted in Taiwan by IDUs after release from the criminal justice system.


Asunto(s)
Infecciones por VIH/diagnóstico , Saliva , Mercadeo Social , Abuso de Sustancias por Vía Intravenosa/psicología , Adulto , Recolección de Datos , Seropositividad para VIH/diagnóstico , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Persona de Mediana Edad , Prisioneros , Juego de Reactivos para Diagnóstico , Taiwán , Adulto Joven
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