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1.
Chem Biodivers ; 16(4): e1800646, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30706997

RESUMEN

A new series of (sulfonamido)propanamides (6a1-6a13, 6b1-6b15, 7c1-7c5, 6d1-6d5, 6e1-6e6) was designed and synthesized. All the synthesized compounds were characterized by NMR and mass spectrometry. The target compounds were evaluated for their in vitro cytotoxic activity against hepatocellular carcinoma (HepG2), fibrosarcoma (HT-1080), mouth epidermal carcinoma (KB), and breast adenocarcinoma (MCF-7) cell lines with the sulforhodamine B (SRB) assay, with gemcitabine and mitomycin C as positive controls. Most of these compounds exhibit a more potent cytotoxic effect than the positive control group on various cancer cell lines and the most potent compound, 6a7, shows the IC50 values of 29.78±0.516 µm, 30.70±0.61 µm, and 64.89±3.09 µm in HepG2, HT-1080, KB, and MCF-7 cell lines, respectively. Thus, these compounds with potent cytotoxic activity have potential for development as new chemotherapy agents.


Asunto(s)
Antineoplásicos/farmacología , Diseño de Fármacos , Propionatos/farmacología , Sulfonamidas/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Propionatos/síntesis química , Propionatos/química , Relación Estructura-Actividad , Sulfonamidas/síntesis química , Sulfonamidas/química
2.
Environ Sci Technol ; 50(2): 924-31, 2016 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-26667586

RESUMEN

Plastic pollution represents a major and growing global problem. It is well-known that plastics are a source of chemical contaminants to the aquatic environment and provide novel habitats for marine organisms. The present study quantified the impacts of plastic leachates from the seven categories of recyclable plastics on larval survival and settlement of barnacle Amphibalanus (=Balanus) amphitrite. Leachates from plastics significantly increased barnacle nauplii mortality at the highest tested concentrations (0.10 and 0.50 m(2)/L). Hydrophobicity (measured as surface energy) was positively correlated with mortality indicating that plastic surface chemistry may be an important factor in the effects of plastics on sessile organisms. Plastic leachates significantly inhibited barnacle cyprids settlement on glass at all tested concentrations. Settlement on plastic surfaces was significantly inhibited after 24 and 48 h, but settlement was not significantly inhibited compared to the controls for some plastics after 72-96 h. In 24 h exposure to seawater, we found larval toxicity and inhibition of settlement with all seven categories of recyclable commercial plastics. Chemical analysis revealed a complex mixture of substances released in plastic leachates. Leaching of toxic compounds from all plastics should be considered when assessing the risks of plastic pollution.


Asunto(s)
Plásticos/química , Plásticos/toxicidad , Agua de Mar/química , Thoracica/efectos de los fármacos , Animales , Larva/efectos de los fármacos , Pruebas de Toxicidad
3.
Nanomedicine ; 10(8): 1871-5, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25101881

RESUMEN

MicroRNAs (miRNAs) are master regulators of gene expression at post-transcriptional level. The present study investigated the involvement of miRNAs in topological guidance of neurite outgrowth in an NGF treated PC12 cell model cultured on nano-patterned polyethylene terephthalate (PET) substrates fabricated with interference lithography. The expressions of 38 neuronal miRNAs were measured and 3 were found to be differentially regulated during topological guidance of neurite outgrowth. Altering the intracellular levels of these miRNAs disrupted the orderly growth of neurite along nano-patterned substrate. Our results showed miRNAs to be versatile regulators and their involvement should be thoroughly investigated for better understanding of biological processes. FROM THE CLINICAL EDITOR: In this basic science study, strong evidence was found that topological guidance is only one factor, and miRNA-s regulate axonal outgrowth from neurites. Nano-patterned polyethylene terephthalate substrates were used for the study, fabricated using interference lithography. Further studies of this biologically relevant process may pave the way to clinically useful axonal regrowth and axonal guidance methods.


Asunto(s)
MicroARNs/genética , Neuritas/metabolismo , Neuritas/fisiología , Tereftalatos Polietilenos/química , Animales , Humanos , MicroARNs/fisiología , Células PC12 , Ratas
4.
J Food Prot ; 87(2): 100213, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38176613

RESUMEN

Food-contact surfaces showing signs of wear pose a substantial risk of Listeria monocytogenes contamination and may serve as persistent sources of cross-contamination in fresh produce packinghouses. This study offers a comprehensive exploration into the influence of surface defects on the efficacies of commonly used sanitizers against L. monocytogenes biofilms on major food-contact surfaces. The 7-day-old L. monocytogenes biofilms were cultivated on food-contact surfaces, including stainless steel, polyvinyl chloride, polyester, low-density polyethylene, and rubber, with and without defects and organic matter. Biofilms on those surfaces were subjected to treatments of 200 ppm chlorine, 400 ppm quaternary ammonium compound (QAC), or 160 ppm peroxyacetic acid (PAA). Results showed that surface defects significantly (P < 0.05) increased the population of L. monocytogenes in biofilms on non-stainless steel surfaces and compromised the efficacies of sanitizers against L. monocytogenes biofilms across various surface types. A 5-min treatment of 200 ppm chlorine caused 1.84-3.39 log10 CFU/coupon reductions of L. monocytogenes on worn surfaces, compared to 2.79-3.93 log10 CFU/coupon reduction observed on new surfaces. Similarly, a 5-min treatment with 400 ppm QAC caused 2.05-2.88 log10 CFU/coupon reductions on worn surfaces, compared to 2.51-3.66 log10 CFU/coupon reductions on new surfaces. Interestingly, PAA sanitization (160 ppm, 1 min) exhibited less susceptibility to surface defects, leading to 3.41-4.35 log10 CFU/coupon reductions on worn surfaces, in contrast to 3.68-4.64 log10 CFU/coupon reductions on new surfaces. Furthermore, apple juice soiling diminished the efficacy of sanitizers against L. monocytogenes biofilms on worn surfaces (P < 0.05). These findings underscore the critical importance of diligent equipment maintenance and thorough cleaning processes to effectively eliminate L. monocytogenes contamination on food-contact surfaces.


Asunto(s)
Listeria monocytogenes , Árboles , Contaminación de Alimentos/prevención & control , Contaminación de Alimentos/análisis , Frutas/química , Cloro , Recuento de Colonia Microbiana , Biopelículas , Ácido Peracético/farmacología , Microbiología de Alimentos , Acero Inoxidable/análisis
5.
ACS Nano ; 18(33): 22104-22121, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39102149

RESUMEN

Digital light processing (DLP) bioprinting, known for its high resolution and speed, enables the precise spatial arrangement of biomaterials and has become integral to advancing tissue engineering and regenerative medicine. Nevertheless, inherent light scattering presents significant challenges to the fidelity of the manufactured structures. Herein, we introduce a photoinhibition strategy based on Rutin nanoparticles (Rnps), attenuating the scattering effect through concurrent photoabsorption and free radical reaction. Compared to the widely utilized biocompatible photoabsorber tartrazine (Tar), Rnps-infused bioink enhanced printing speed (1.9×), interlayer homogeneity (58% less overexposure), resolution (38.3% improvement), and print tolerance (3× high-precision range) to minimize trial-and-error. The biocompatible and antioxidative Rnps significantly improved cytocompatibility and exhibited resistance to oxidative stress-induced damage in printed constructs, as demonstrated with human induced pluripotent stem cell-derived endothelial cells (hiPSC-ECs). The related properties of Rnps facilitate the facile fabrication of multimaterial, heterogeneous, and cell-laden biomimetic constructs with intricate structures. The developed photoinhibitor, with its profound adaptability, promises wide biomedical applications tailored to specific biological requirements.


Asunto(s)
Bioimpresión , Luz , Nanopartículas , Rutina , Humanos , Rutina/química , Rutina/farmacología , Nanopartículas/química , Ingeniería de Tejidos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos
6.
Nat Commun ; 14(1): 3598, 2023 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-37328460

RESUMEN

Towards intracellular engineering of living organisms, the development of new biocompatible polymerization system applicable for an intrinsically non-natural macromolecules synthesis for modulating living organism function/behavior is a key step. Herein, we find that the tyrosine residues in the cofactor-free proteins can be employed to mediate controlled radical polymerization under 405 nm light. A proton-coupled electron transfer (PCET) mechanism between the excited-state TyrOH* residue in proteins and the monomer or the chain transfer agent is confirmed. By using Tyr-containing proteins, a wide range of well-defined polymers are successfully generated. Especially, the developed photopolymerization system shows good biocompatibility, which can achieve in-situ extracellular polymerization from the surface of yeast cells for agglutination/anti-agglutination functional manipulation or intracellular polymerization inside yeast cells, respectively. Besides providing a universal aqueous photopolymerization system, this study should contribute a new way to generate various non-natural polymers in vitro or in vivo to engineer living organism functions and behaviours.


Asunto(s)
Saccharomyces cerevisiae , Tirosina , Tirosina/química , Transporte de Electrón , Protones , Polímeros/química , Polimerizacion
7.
Calcif Tissue Int ; 88(1): 75-86, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21110188

RESUMEN

The role of the small Rho GTPase Rac2 in mature osteoclasts has not been extensively studied. Rac2(-/-) mice are of normal size and have normal tooth eruption. However, femoral cortical thickness was significantly greater in Rac2(-/-) compared to wild-type mice, while percent cortical porosity was lower. As assessed by histomorphometry, trabecular bone mass was significantly higher in male Rac2(-/-) than wild-type animals, although trabecular bone mass was similar when data from male and female animals were combined. There were no significant differences in the number of osteoblasts per bone surface; however, the number of osteoclasts per total bone area tended to be higher in Rac2(-/-) mice and was significantly higher in male Rac2(-/-) mice. In the aggregate, these data suggested a defect in osteoclast function and, consistent with that, rates of bone resorption were significantly reduced in Rac2(-/-) osteoclasts. In addition, Rac2(-/-) osteoclasts had a significantly delayed spreading response to treatment with CSF1 for 15 min. Phalloidin staining showed areas of abnormal actin accumulation and impaired actin ring formation in Rac2(-/-) osteoclasts. Finally, Rac2(-/-) osteoclasts showed a marked defect in chemotaxis toward a point source of CSF1, with a dramatic reduction in migratory rate. Together, these findings indicate an important role for Rac2 in mature osteoclasts.


Asunto(s)
Resorción Ósea/genética , Quimiotaxis/genética , Osteoclastos/fisiología , Proteínas de Unión al GTP rac/genética , Animales , Densidad Ósea/genética , Huesos/anatomía & histología , Células Cultivadas , Femenino , Factor Estimulante de Colonias de Macrófagos/metabolismo , Factor Estimulante de Colonias de Macrófagos/fisiología , Masculino , Ratones , Ratones Noqueados , Tamaño de los Órganos/genética , Osteoclastos/metabolismo , Proteínas de Unión al GTP rac/metabolismo , Proteínas de Unión al GTP rac/fisiología , Proteína RCA2 de Unión a GTP
8.
Chem Commun (Camb) ; 57(88): 11713-11716, 2021 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-34695173

RESUMEN

A spatially segregative coacervate-in-proteinosome hybrid microcompartment is constructed by co-encapsulation of either positively or negatively charged polyelectrolytes within proteinosomes with enhanced cascade enzymatic reactions, providing a step towards the development of artificial eukaryotic cell like microcompartments.


Asunto(s)
Células Eucariotas/metabolismo , Peroxidasa de Rábano Silvestre/metabolismo , Polietilenglicoles/metabolismo , Células Eucariotas/química , Peroxidasa de Rábano Silvestre/química , Estructura Molecular , Polielectrolitos/química , Polietilenglicoles/química
9.
Aquat Toxicol ; 220: 105396, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31927063

RESUMEN

Fish studies report consumption of microplastics (MPs) in the field, and concern exists over associated risks. However, laboratory studies with adult fish are scarce. In this study, outbred and see-through Japanese medaka (Oryzias latipes) were fed diets amended with 500, 1000, or 2000 µg/g 10 µm fluorescent spherical polystyrene microplastics (MPs) for 10 weeks during their maturation from juveniles to spawning adults. No behavioral changes, growth differences, or mortalities occurred. In vivo examinations and histologic sections showed no evidence of translocation of MPs from the gut to other internal organs. Mature females experienced dose-dependent decreases in egg number. Scanning electron microscopic examination of gills and gut revealed MPs in both areas. Swollen enterocytes were observed on apices of gut folds only in exposed fish. These were particularly apparent in foreguts of the high exposure group. Enterocytes with eroded brush borders were found in foregut of high and medium exposure groups. Increased mucus production, in long strands and sheets, was seen over primary and secondary lamellae of gills. Histological analysis showed alteration in buccal cavity, kidney, and spleen. Thickening and roughening of epithelium in headgut and pharynx and cellular alterations in spleen occurred. Head kidney was the primary site of alteration. Glomerulopathy and nephrogenesis were observed in exposed fish, increasing in severity with exposure level.


Asunto(s)
Exposición Dietética/efectos adversos , Microplásticos/toxicidad , Oryzias/crecimiento & desarrollo , Poliestirenos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Exposición Dietética/análisis , Femenino , Branquias/química , Branquias/efectos de los fármacos , Mucosa Intestinal/química , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/patología , Masculino , Microplásticos/análisis , Poliestirenos/análisis , Bazo/química , Bazo/efectos de los fármacos , Bazo/patología , Contaminantes Químicos del Agua/análisis
10.
J Biomed Opt ; 13(5): 054026, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19021406

RESUMEN

The use of microfluidics for biofluid analysis offers a cheaper alternative to conventional techniques in disease diagnosis. However, traditional microfluidics design may be complicated by the need to incorporate separation elements into the system in order to facilitate specific molecular detection. Alternatively, an optical technique known as surface-enhanced Raman spectroscopy (SERS) may be used to enable identification of analyte molecules directly from a complex sample. This will not only simplify design but also reduce overall cost. The concept of SERS-based microfluidics is however not new and has been demonstrated previously by mixing SERS-active metal nanoparticles with a model sample, in situ, within the microchannel. Although the SERS reproducibility of these systems was shown to be acceptable, it is, however, not stable toward variations in the salt content of the sample, as will be shown in this study. We have proposed a microfluidics design whereby periodic SERS-active metal nanostructures are fabricated directly into the microchannel via a simple method of spin coating. Using artificial as well as human urine samples, we show that the current microfluidics is more stable toward variations in the sample's ionic strength.


Asunto(s)
Compuestos Epoxi/química , Oro Coloide/química , Técnicas Analíticas Microfluídicas/instrumentación , Nanoestructuras/química , Nanotecnología/instrumentación , Polímeros/química , Espectrometría Raman/instrumentación , Urinálisis/instrumentación , Diseño Asistido por Computadora , Diseño de Equipo , Análisis de Falla de Equipo , Análisis de Inyección de Flujo/instrumentación , Nanoestructuras/ultraestructura , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Propiedades de Superficie
11.
Environ Pollut ; 218: 973-980, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27569057

RESUMEN

Plastics are common and pervasive anthropogenic debris in marine environments. Floating plastics provide opportunities to alter the abundance, distribution and invasion potential of sessile organisms that colonize them. We selected plastics from seven recycle categories and quantified settlement of (i) bryozoans Bugula neritina (Linnaeus, 1758) in the lab and in the field, and of (ii) barnacles Amphibalanus (= Balanus) amphitrite (Darwin, 1854) in the field. In the laboratory we cultured barnacles on the plastics for 8 weeks and quantified growth, mortality, and breaking strength of the side plates. In the field all recyclable plastics were settlement substrata for bryozoans and barnacles. Settlement depended on the type of plastic. Fewer barnacles settled on plastic surfaces compared to glass. In the lab and in the field, bryozoan settlement was higher on plastics than on glass. In static laboratory rearing, barnacles growing on plastics were initially significantly smaller than on glass. This suggested juvenile barnacles were adversely impacted by materials leaching from the plastics. Barnacle mortality was not significantly different between plastic and glass surfaces, but breaking strength of side plates of barnacles on polyvinyl chloride (PVC) and polycarbonate (PC) were significantly lower than breakage strength on glass. Plastics impact marine ecosystems directly by providing new surfaces for colonization with fouling organisms and by contaminants shown previously to leach out of plastics and impact biological processes.


Asunto(s)
Briozoos/crecimiento & desarrollo , Briozoos/metabolismo , Plásticos/toxicidad , Thoracica/crecimiento & desarrollo , Thoracica/metabolismo , Adolescente , Animales , Vidrio , Humanos , Larva/crecimiento & desarrollo , Cemento de Policarboxilato/toxicidad , Cloruro de Polivinilo/toxicidad , Propiedades de Superficie
12.
Biosens Bioelectron ; 77: 687-94, 2016 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-26496223

RESUMEN

Escherichia coli O157:H7 is one of the most notorious foodborne pathogens causing serious disease at low infectious dose. To protect consumers from deadly foodborne E. coli O157:H7 infection, it is vital to develop a simple, reliable, sensitive and rapid method which can detect low level E. coli O157:H7 in foods at real-time. We have successfully developed a novel immunochromatographic assay (ICA) with enhanced sensitivity for the visual and quantitative detection of E. coli O157:H7. Sandwich-type immunoreactions were performed on the ICA, and Pt-Au bimetal nanoparticles (NPs) were accumulated on the test zone. The signal amplification is based on Pt-Au bimetal NPs possessing high peroxidase activity toward 3,3',5,5'-tetramethylbenzidine, which can produce characteristic colored bands and thus, enable visual detection of E. coli O157:H7 without instrumentation. The innovative aspect of this approach lies in the visualization and quantification of target pathogen through the detection of color intensity. Due to the excellent peroxidase activity of Pt-Au NPs, they emit strong visible color intensity in less than 1 min for visual observation even in low concentration range of E. coli O157:H7. Quantification was performed using a commercial assay meter. The sensitivity was improved more than 1000-folds compared to the conventional test strip based on colored gold-colloids. Although the feasibility was demonstrated using E. coli O157:H7 as a model analyte, this approach could be easily developed to be a universal signal amplification technique and applied to detection of a wide variety of foodborne pathogens and protein biomarkers.


Asunto(s)
Carga Bacteriana/instrumentación , Conductometría/instrumentación , Escherichia coli O157/aislamiento & purificación , Oro/química , Nanopartículas del Metal/química , Platino (Metal)/química , Aleaciones/química , Materiales Biomiméticos/química , Diseño de Equipo , Análisis de Falla de Equipo , Nanopartículas del Metal/ultraestructura , Microelectrodos , Peroxidasa/química , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
13.
Int J Clin Exp Pathol ; 7(10): 7094-9, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25400803

RESUMEN

Two cases of brown tumor of the humerus caused by ectopic parathyroid adenomas were presented, which to our knowledge has not been previously documented in the international literature. There are two highlights in these two cases. First, brown tumors of the long bones may commonly involve femur and tibia, rarely involve humerus in association with primary hyperparathyroidism. Second, ectopic parathyroid adenomas of our patient had an unusual location of this disorder. We explored the role of ultrasound, MIBI scintigraphy as well as FNAB (fine needle aspiration biopsy) in diagnosis of brown tumor especially simultaneously occurrence of ectopic parathyroid adenomas and the importance of a thorough diagnostic work-up. The contemporary diagnosis and treatment options will be emphasized.


Asunto(s)
Adenoma/complicaciones , Neoplasias Óseas/etiología , Coristoma/complicaciones , Húmero/patología , Hiperparatiroidismo Primario/etiología , Mandíbula , Neoplasias Mandibulares/complicaciones , Glándulas Paratiroides , Neoplasias de las Paratiroides/complicaciones , Neoplasias de la Tiroides/complicaciones , Adenoma/patología , Adenoma/cirugía , Adolescente , Adulto , Biopsia con Aguja Fina , Neoplasias Óseas/patología , Coristoma/diagnóstico , Coristoma/cirugía , Femenino , Humanos , Húmero/diagnóstico por imagen , Hiperparatiroidismo Primario/diagnóstico , Hiperparatiroidismo Primario/cirugía , Masculino , Neoplasias Mandibulares/patología , Neoplasias Mandibulares/cirugía , Neoplasias de las Paratiroides/patología , Neoplasias de las Paratiroides/cirugía , Valor Predictivo de las Pruebas , Cintigrafía , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/cirugía , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Ultrasonografía
14.
Thorac Cancer ; 4(4): 474-478, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28920228

RESUMEN

A brown tumor is a non-neoplasm mainly caused by hyperparathyroidism. It often occurs in the pelvis, ribs, long bone shaft, clavicle, and jaw. We introduce three cases of primary hyperparathyroidism, with the first symptom of brown tumor of the ribs, and discuss the image characteristics within the literature. We then propose the value of ultrasound in the diagnosis of brown tumor.

15.
J Biomed Nanotechnol ; 8(5): 779-85, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22888748

RESUMEN

In this study, a novel three-dimensional fluffy PPy conductive fibrous scaffold (3D-cFSs) was fabricated by electrospinning technique combined with situ surface polymerization. Chemical compositions, morphology were characterized by fourier transform infrared (FTIR) and scanning electron microscopy (SEM). The results showed that the average diameter of PPy coated PLLA fibers in the 3D-cFSs was 2.086 microm, the thickness of PPy nano-layer was -45 nm. These PPy coated PLLA fibers were in discrete state, the size of interconnected pores in the 3D-cFSs was from 50 microm to 100 microm, this unique structure ensured that cells can entry into internal of 3D-cFSs smoothly without any other extra help to achieve three-dimensional cell culture (3D-culture). Rat pheochromocytoma 12 (PC12) cells (as model cell) were cultured in the 3D-cFSs to evaluate its potential application for nerve tissue engineering. The interaction between cell and scaffold was test by detecting the cell proliferation, viability, and morphology. After 3 days culture, the number of PC12 in 3D-cFSs were much higher than that on the conductive fibrous meshes (cFMs) and well developed cell-fibers constructs were observed from fluorescence image and SEM of PC12 in the central of 3D-cFSs. These results showed that the 3D-cFSs provided cell 3D-culture, and improved cell growth. Therefore, we suggest that the 3D-cFSs maybe a suitable scaffold for the nerve tissue engineering as cells substrate to apply electrical stimulation.


Asunto(s)
Ácido Láctico/química , Nanoestructuras/química , Neuronas/citología , Neuronas/fisiología , Polímeros/química , Pirroles/química , Ingeniería de Tejidos/instrumentación , Andamios del Tejido , Animales , Línea Celular , Proliferación Celular , Materiales Biocompatibles Revestidos/síntesis química , Conductividad Eléctrica , Diseño de Equipo , Nanoestructuras/ultraestructura , Células PC12 , Poliésteres , Ratas
16.
J Biomed Nanotechnol ; 8(1): 1-9, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22515089

RESUMEN

Electrospinning is an exciting technique attracting more and more attention as a potential solution to the current challenges in the field of tissue engineering. This technique can be used to produce fibrous scaffolds with excellent biocompatibility and biodegradability, as well as suitable micro-/nanostructure to induce desired cellular activities and to guide tissue regeneration. In order to develop electrospun fibrous scaffolds for these applications, different biocompatible materials including natural polymers, synthetic polymers and inorganic substances and preparations have been used to fabricate electrospun fibers with different structures and morphologies. This review briefly describes the development of the technique, focusing on several typically electrospun materials, surface modification of electrospun fibers, and current applications in tissue engineering.


Asunto(s)
Técnicas Electroquímicas , Nanofibras , Ingeniería de Tejidos , Andamios del Tejido , Animales , Técnicas de Cultivo de Célula , Humanos , Nanotecnología , Polímeros
17.
Langmuir ; 24(20): 11967-74, 2008 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-18759505

RESUMEN

Nanocomposites of poly- p-phenyleneethynylene gold nanoparticles (PPE-Au) were synthesized via directly grafting maleimide functionalized gold nanoparticles (MA-Au) onto PPE chains by a mild Diels-Alder reaction. The Diels-Alder reaction between copolymers and MA-Au leads to self-assembly of the MA-Au as well as enhances electronic communication between the copolymers and inorganic particles. The as-prepared hybrid nanoassemblies show homogeneous status and well-defined interfaces, which facilitate the electronic interaction between conjugated polymers and gold nanoparticles. Moreover, dramatic photophysical properties and an influence on the assembly behavior of gold nanoparticles are also exhibited, which allows this procedure to be performed as a smart assay for monitoring the process of the Diels-Alder reaction.


Asunto(s)
Oro/química , Nanopartículas del Metal/química , Nanotecnología/métodos , Polímeros/química , Química Física/métodos , Electrónica , Compuestos Inorgánicos , Luz , Maleimidas/química , Microscopía Electrónica de Transmisión , Modelos Químicos , Nanopartículas/química , Nanoestructuras , Fotoquímica/métodos , Factores de Tiempo
18.
Shanghai Kou Qiang Yi Xue ; 16(5): 461-5, 2007 Oct.
Artículo en Zh | MEDLINE | ID: mdl-18004472

RESUMEN

PURPOSE: The purpose of this study is to investigate the mechanics of mandibular advancement devices (MAD) assisted uvulopalatopharyngoplasty (UPPP) for treatment of obstructive sleep apnea and hypopnea syndrome (OSAHS). METHODS: 10 patients (8 males, 2 females) were diagnosed as OSAHS by PSG and operated by UPPP. Mandibular advancement devices was used after operation. One month later, all the patients were evaluated by PSG and cephalometric analysis. Paired t test and correlative analysis were carried out using SPSS 10.0 software package. RESULTS: Cephalometric analysis indicated that MCF, angle C3-Rgn-H, Ant In Mx. Ht were significantly different before and after MAD treatment. AHI was correlative with Ant In Mx. Ht and ratio of tongue area and intermaxillary area(P<0.05). CONCLUSIONS: MAD in patients undergoing UPPP results in changes of mandibular position, instead of changes of enlargement of velopharynx. Supported by Shanghai Leading Academic Discipline Project (Grant No.Y0203).


Asunto(s)
Avance Mandibular , Hueso Paladar/cirugía , Faringe/cirugía , Apnea Obstructiva del Sueño/cirugía , Úvula/cirugía , Cefalometría , China , Humanos , Mandíbula
19.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 38(6): 432-4, 2003 Nov.
Artículo en Zh | MEDLINE | ID: mdl-14703476

RESUMEN

OBJECTIVE: To study the effect of traumatic occlusion on CGRP-immunoreactive (CGRP-IR) nerve fibres in rat molar pulp and observe the recovery of CGRP-IR nerve fibres after removal of traumatic occlusion. METHODS: To observe immunohistochemically the change of CGRP-IR nerve fibres in molar pulp during traumatic occlusion and after removal. RESULTS: The increase of number, density and morphology of CGRP-IR nerve fibres in traumatic occlusion group was more than in control group, however, the changes of CGRP-IR nerve fibres in removal of traumatic occlusion group were less than in control group. CONCLUSIONS: The changes of CGRP-IR nerve fibres in number, morphology, and density are induced by traumatic occlusion in rat molar pulp, however, the nerve fibres recover to normal by removal of traumatic occlusion.


Asunto(s)
Péptido Relacionado con Gen de Calcitonina/análisis , Oclusión Dental Traumática/patología , Pulpa Dental/inervación , Diente Molar/inervación , Fibras Nerviosas/química , Animales , Oclusión Dental Traumática/metabolismo , Oclusión Dental Traumática/terapia , Inmunohistoquímica , Masculino , Ratas , Ratas Sprague-Dawley
20.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 39(5): 421-4, 2004 Sep.
Artículo en Zh | MEDLINE | ID: mdl-15498355

RESUMEN

OBJECTIVE: To investigate changes of two sodium channels, PN(3) and NaN, during orofacial pain by occlusal trauma in rat. METHODS: Expressions of PN(3) mRNA and NaN mRNA in trigeminal ganglion were tested during various periods of persistent occlusal trauma with reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: In groups, including control, occlusal trauma groups, PN(3) mRNA and NaN mRNA were all expressed in trigeminal ganglion neurons. In the control group, there were similar density values bilaterally. In the occlusal trauma group, the density values in gel electrophoresis of PN(3) mRNA and NaN mRNA on the intervention side were slightly greater than those on the control side. CONCLUSIONS: The stimulation of occlusal trauma upregulates expressions of PN(3) mRNA and NaN mRNA, which suggests the signal occurring and conduction of chronic pain by occlusal trauma have the same molecular mechanism of sodium channel as inflammatory pain.


Asunto(s)
Oclusión Dental Traumática/fisiopatología , Canales de Sodio/biosíntesis , Ganglio del Trigémino/metabolismo , Animales , Dolor Facial/etiología , Masculino , Canal de Sodio Activado por Voltaje NAV1.8 , ARN Mensajero/biosíntesis , Ratas , Ratas Sprague-Dawley , Canales de Sodio/genética
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