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1.
J Cell Physiol ; 239(4): e31196, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38240115

RESUMEN

The NOD-, LRR-, and Pyrin domain-containing protein 3 (NLRP3) inflammasome plays key roles in regulating inflammation. Numerous studies show that the abnormal activation of NLRP3 associates with the initiation and progression of various diseases. Hence, the NLRP3 inflammasome may be a promising therapeutic target for these diseases. Octyl gallate (OG) is a small molecule with antioxidant, antimicrobial, antifungal, and anti-inflammatory activities; however, the mechanism underlying its anti-inflammatory activity is still unclear. Here, we developed a screening system for NLRP3-inflammasome inhibitors. A total of 3287 small molecules were screened for inhibitors of nigericin-induced NLRP3 oligomerization. OG was identified as a novel inhibitor. We show that OG directly targets the LRR domain of NLRP3 and thereby blocks the inflammatory cascade of the NLRP3 inflammasome. This contrasts with the mode-of-action of other direct NLRP3 inhibitors, which all bind to the NACHT domain of NLRP3. Interestingly, OG also inhibits the priming step by downregulating the Raf-MEK1/2-ERK1/2 axis. Thus, OG inhibits the NLRP3 inflammasome by two distinct mechanisms. Importantly, OG injection ameliorated the inflammation in mouse models of foot gout and sepsis. Our study identifies OG as a potential therapeutic agent for NLRP3-associated diseases.


Asunto(s)
Antiinflamatorios , Ácido Gálico , Inflamasomas , Proteína con Dominio Pirina 3 de la Familia NLR , Animales , Ratones , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Ácido Gálico/análogos & derivados , Inflamasomas/efectos de los fármacos , Inflamación/tratamiento farmacológico , Proteína con Dominio Pirina 3 de la Familia NLR/química , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Ratones Endogámicos C57BL , Masculino , Dominios Proteicos
2.
J Am Chem Soc ; 146(9): 6266-6273, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38394690

RESUMEN

Determining the aromaticity of various fluorinated benzenes is challenging as easily obtained experimental aromaticity [Δδ(Houter - Hinner)] necessitates the chemical shifts of inner and outer protons. This issue was addressed in porphyrinoids by replacing the electron-withdrawing (E.W.) groups at the meso-positions of porphyrins and allyliporphyrins. Electronic effects on aromaticity in porphyrinoids have not been thoroughly examined in the literature. In porphyrins, the effect of E.W. groups is minimal, making it difficult to establish a clear relationship between the aromaticity strength and E.W. groups. Conversely, in allyliporphyrins, stronger E.W. groups, such as indandione (IND) derivatives, significantly reduce the aromaticity of the parent structure. The IND derivatives disrupted the aromatic pathway of allyliporphyrin more effectively than those attached to porphyrins. This is attributed to the absence of ß-carbons in allyliporphyrins. The effect of electron-donating (E.D.) groups on porphyrins and allyliporphyrins was further investigated. Contrary to the initial assumption that the E.D. groups might enhance aromaticity owing to their ability to increase electron density, as the strength of the E.D. groups increased, the aromaticity of the porphyrinoids decreased. Despite the modest reduction in aromaticity, any form of electron perturbation reduces aromaticity. The aromaticity of various fluorinated benzenes is expected to parallel our observations of porphyrinoids as representative aromatic polyenes.

3.
Nano Lett ; 23(17): 7897-7905, 2023 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-37435905

RESUMEN

A new type of microfluidic bioreactor with fibrous micromixers for the ingredient mixing and a long macrochannel for the in vitro transcription reaction was fabricated for the continuous production of mRNA. The diameter of the fibrous microchannels in the micromixers was tuned by using an electrospun microfibrous disc with different microfiber diameters. The micromixer with a larger diameter of fibrous microchannels exhibited a better mixing performance than the others. The mixing efficiency was increased to 0.95 while the mixture was passed through the micromixers, suggesting complete mixing. To demonstrate the continuous production of mRNA, the ingredients for in vitro transcription were introduced into the perfluoropolyether microfluidic bioreactor. The mRNA synthesized by the microfluidic bioreactor had the same sequence and in vitro/in vivo performances as those prepared by the bulk reaction. The continuous reaction in the microfluidic bioreactor with efficient mixing performance can be used as a powerful platform for various microfluidic reactions.


Asunto(s)
Técnicas Analíticas Microfluídicas , Microfluídica , Diseño de Equipo
4.
Macromol Rapid Commun ; 43(21): e2200423, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36056922

RESUMEN

CO2 -triggered in situ hydrogels is developed from waterborne poly(ε-caprolactone)-based polyurethane (PU) dispersion and aqueous polyethyleneimine (PEI) solution without any other chemicals and apparatus (e.g., UV light). In the approach, nontoxic CO2 in air is used as a selective trigger for the hydrogel formation. CO2 adsorption onto PEI results in the formation of ammonium cations in PEI and the subsequent multiple ionic crosslinking between PU and PEI chains. Besides the amount of CO2 in air, the rate of hydrogel formation can be controlled by NaHCO3 in the PU-PEI mixture, which serves as a CO2 supplier. The PU hydrogels exhibit tough and stretchable properties with high tensile strength (2.05 MPa) and elongation at break (438.24%), as well as biocompatibility and biodegradability. In addition, the PU hydrogels exhibit high adhesion strength on skin and injectability due to the in situ formation. It is believed that these PU hydrogels have the ideal features for various future applications, such as tissue adhesion barriers, wound dressing, artificial skin, and injectable fillers.


Asunto(s)
Hidrogeles , Poliuretanos , Hidrogeles/química , Poliuretanos/química , Polietileneimina/química , Dióxido de Carbono , Resistencia a la Tracción
5.
Breast Cancer Res Treat ; 180(3): 657-663, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32072339

RESUMEN

PURPOSE: Adjuvant treatment for breast cancer in postmenopausal women is a risk factor for bone loss. However, the association between bone mineral density (BMD) changes in premenopausal breast cancer patients and various adjuvant treatment regimens is not well characterized. In this study, we evaluated the changes in BMD according to adjuvant treatment in premenopausal women with breast cancer. METHODS: Between 2006 and 2010, BMD data of 910 premenopausal women with breast cancer before operation and 1, 2, 3.5, and 5 years post-operation were retrospectively analyzed. The patients were divided according to the type of treatment: observation (O), tamoxifen (T), chemotherapy (C), C followed by T (C → T), and gonadotropin-releasing hormone (GnRH) agonist with T (G + T). RESULTS: After 5 years of follow-up, BMD changes were similar between the T and O groups (all p > 0.05). Within 1 year of treatment, the C group showed the most significant BMD loss. The C → T and G + T groups showed more significant BMD loss in the lumbar spine and femur than the O and T groups (both p < 0.001, both). After 1 year of treatment, BMD loss in the lumbar spine was significantly greater in the C → T and G + T groups than in the T group; this tendency was maintained for 5 years of treatment (all p < 0.005). CONCLUSION: Premenopausal women who received adjuvant treatment which induced menopause showed significant bone loss which lasted for 5 years. Although no significant difference was observed between the O and T groups, tamoxifen treatment during chemotherapy or GnRH agonist treatment might prevent bone loss.


Asunto(s)
Antineoplásicos Hormonales/farmacología , Densidad Ósea/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Quimioterapia Adyuvante/métodos , Premenopausia/efectos de los fármacos , Tamoxifeno/farmacología , Adulto , Neoplasias de la Mama/patología , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Adulto Joven
6.
Sensors (Basel) ; 20(5)2020 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-32143335

RESUMEN

The food industry requires rapid and simple detection methods for preventing harm from pathogenic bacteria. Until now, various technologies used to detect foodborne bacteria were time-consuming and laborious. Therefore, we have developed an automated immunomagnetic separation combined with a colorimetric assay for the rapid detection of E. coli O157:H7 in food samples. The colorimetric detection method using enzymatic reaction is fascinating because of its simplicity and rapidity and does not need sophisticated devices. Moreover, the proposed procedures for the detection of bacteria in food take less than 3 h including pre-enrichment, separation and detection steps. First, target-specific immunomagnetic beads were introduced to contaminated milk in a pre-enrichment step. Second, the pre-enriched sample solution containing target bacteria bound on immunomagnetic beads was injected into an automated pretreatment system. Subsequently, the immunomagnetic beads along with target bacteria were separated and concentrated into a recovery tube. Finally, released ß-galactosidase from E. coli O157:H7 after lysis was reacted with chlorophenol red ß-galactopyranoside (CPRG) used as a substrate and the colorimetric change of CPRG was determined by absorbance measuring or the naked eye. By the proposed approach in this study, we could detect 3 × 102 CFU/mL of E. coli O157:H7 from a milk sample within 3 h.


Asunto(s)
Colorimetría/métodos , Pruebas de Enzimas , Escherichia coli O157/aislamiento & purificación , Separación Inmunomagnética/métodos , beta-Galactosidasa/metabolismo , Animales , Automatización , Escherichia coli O157/ultraestructura , Leche/microbiología
7.
Sensors (Basel) ; 17(12)2017 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-29210982

RESUMEN

We experimentally modulate the refractive index and the absorption coefficient of an SU-8 dry film in the terahertz region by UV light (362 nm) exposure with time dependency. Consequently, the refractive index of SU-8 film is increased by approximately 6% after UV light exposure. Moreover, the absorption coefficient also changes significantly. Using the reflective terahertz imaging technique, in addition, we can read security information printed by UV treatment on an SU-8 film that is transparent in the visible spectrum. From these results, we successfully demonstrate security printing and reading by using photoresist materials and the terahertz technique. This investigation would provide a new insight into anti-counterfeiting applications in fields that need security.

8.
Int J Mol Sci ; 18(1)2017 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-28075349

RESUMEN

Irregularities in the cellular uptake of thyroid hormones significantly affect muscle development and regeneration. Herein, we report indispensable role of transthyretin (TTR) in maintaining cellular thyroxine level. TTR was found to enhance recruitment of muscle satellite cells to the site of injury, thereby regulating muscle regeneration. Fluorescence-activated cell sorting (FACS) and immunofluorescence analysis of TTRwt (TTR wild type) and TTRkd (TTR knock-down) cells revealed that TTR controlled cell cycle progression by affecting the expression of Cyclin A2. Deiodinase 2 (D2) mediated increases in triiodothyronine levels were found to regulate the expression of myogenic marker, myogenin (MYOG). Moreover, use of a coumarin derivative (CD) revealed a significant reduction in cellular thyroxine, thereby indicating that TTR play a role in the transport of thyroxine. Taken together, these findings suggest that TTR mediated transport of thyroxine represents a survival mechanism necessary for the myogenic program. The results of this study will be highly useful to the strategic development of novel therapeutics to combat muscular dystrophies.


Asunto(s)
Desarrollo de Músculos , Mioblastos/citología , Prealbúmina/metabolismo , Animales , Unión Competitiva/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Línea Celular , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Cumarinas/farmacología , Medio de Cultivo Libre de Suero/farmacología , Técnicas de Silenciamiento del Gen , Masculino , Ratones Endogámicos C57BL , Desarrollo de Músculos/efectos de los fármacos , Músculos/efectos de los fármacos , Músculos/lesiones , Músculos/metabolismo , Mioblastos/efectos de los fármacos , Mioblastos/metabolismo , Tiroxina/metabolismo , Triyodotironina/metabolismo
9.
Molecules ; 21(8)2016 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-27529203

RESUMEN

Despite the widespread use of the five major xanthophylls astaxanthin, ß-cryptoxanthin, canthaxanthin, lutein, and zeaxanthin as dietary supplements, there have been no studies regarding their inhibitory effects on hepatic UDP-glucuronosyltransferases (UGTs). Here, we evaluated the inhibitory potential of these xanthophylls on the seven major human hepatic UGTs (UGT1A1, UGT1A3, UGT1A4, UGT1A6, UGT1A9, UGT2B7 and UGT2B15) in vitro by LC-MS/MS using specific marker reactions in human liver microsomes (except UGT2B15) or recombinant supersomes (UGT2B15). We also predicted potential dietary supplement-drug interactions for ß-cryptoxanthin via UGT1A1 inhibition. We demonstrated that astaxanthin and zeaxanthin showed no apparent inhibition, while the remaining xanthophylls showed only weak inhibitory effects on the seven UGTs. ß-Cryptoxanthin mildly inhibited UGT1A1, UGT1A3, and UGT1A4, with IC50 values of 18.8 ± 2.07, 28.3 ± 4.40 and 34.9 ± 5.98 µM, respectively. Canthaxanthin weakly inhibited UGT1A1 and UGT1A3, with IC50 values of 38.5 ± 4.65 and 41.2 ± 3.14 µM, respectively; and lutein inhibited UGT1A1 and UGT1A4, with IC50 values of 45.5 ± 4.01 and 28.7 ± 3.79 µM, respectively. Among the tested xanthophyll-UGT pairs, ß-cryptoxanthin showed the strongest competitive inhibition of UGT1A1 (Ki, 12.2 ± 0.985 µM). In addition, we predicted the risk of UGT1A1 inhibition in vivo using the reported maximum plasma concentration after oral administration of ß-cryptoxanthin in humans. Our data suggests that these xanthophylls are unlikely to cause dietary supplement-drug interactions mediated by inhibition of the hepatic UGTs. These findings provide useful information for the safe clinical use of the tested xanthophylls.


Asunto(s)
beta-Criptoxantina/farmacología , Cantaxantina/farmacología , Glucuronosiltransferasa/antagonistas & inhibidores , Glucuronosiltransferasa/química , Luteína/farmacología , Zeaxantinas/farmacología , Suplementos Dietéticos , Interacciones Farmacológicas , Inhibidores Enzimáticos/farmacología , Humanos , Concentración 50 Inhibidora , Isoenzimas , Microsomas Hepáticos/enzimología , Xantófilas/farmacología
10.
Foodborne Pathog Dis ; 12(11): 914-20, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26287636

RESUMEN

Emetic toxin-producing Bacillus cereus group species are an important problem, because the staple food for Korean is grains such as rice. In this study, we determined the prevalence (24 of 129 isolates) of emetic B. cereus in 36,745 stool samples from sporadic food-poisoning cases in Korea between 2007 and 2008. The toxin gene profile, toxin production, and biofilm-forming ability of the emetic B. cereus isolates were investigated. Repetitive element sequence polymorphism polymerase chain reaction fingerprints (rep-PCR) were also used to assess the intraspecific biodiversity of these isolates. Emetic B. cereus was present in 0.07% of the sporadic food-poisoning cases. The 24 emetic isolates identified all carried the nheABC and entFM genes and produced NHE enterotoxin. However, they did not have hemolysin BL toxin or related genes. A relationship between biofilm formation and toxin production was not observed in this study. The rep-PCR fingerprints of the B. cereus isolates were not influenced by the presence of toxin genes, or biofilm-forming ability. The rep-PCR assay discriminated emetic B. cereus isolates from nonemetic isolates, even if this assay did not perfectly discriminate these isolates. Further study on emetic isolates possessing a high degree of diversity may be necessary to evaluate the performance of the subtyping assay to discriminate emetic and nonemetic B. cereus isolates and could provide a more accurate indication of the risk from B. cereus strains.


Asunto(s)
Bacillus cereus/fisiología , Biopelículas/crecimiento & desarrollo , Enterotoxinas/genética , Heces/microbiología , Enfermedades Transmitidas por los Alimentos/microbiología , Bacillus cereus/aislamiento & purificación , Eméticos/análisis , Enterotoxinas/análisis , Proteínas Hemolisinas/análisis , Proteínas Hemolisinas/genética , Humanos , Reacción en Cadena de la Polimerasa , República de Corea
12.
Opt Express ; 22(23): 28977-83, 2014 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-25402136

RESUMEN

We demonstrate real-time continuous-wave terahertz (THz) line-scanned imaging based on a 1 × 240 InGaAs Schottky barrier diode (SBD) array detector with a scan velocity of 25 cm/s, a scan line length of 12 cm, and a pixel size of 0.5 × 0.5 mm². Foreign substances, such as a paper clip with a spatial resolution of approximately 1 mm that is hidden under a cracker, are clearly detected by this THz line-scanning system. The system consists of the SBD array detector, a 200-GHz gyrotron source, a conveyor system, and several optical components such as a high-density polyethylene cylindrical lens, metal cylindrical mirror, and THz wire-grid polarizer. Using the THz polarizer, the signal-to-noise ratio of the SBD array detector improves because the quality of the source beam is enhanced.


Asunto(s)
Arsenicales/química , Sistemas de Computación , Electrónica/instrumentación , Galio/química , Indio/química , Fenómenos Ópticos , Radiación Terahertz
13.
Macromol Rapid Commun ; 35(11): 1033-8, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24700776

RESUMEN

The entrapment of a protein in porous poly(D,L-lactide-co-glycolide) (PLGA) microspheres is demonstrated through the closure of their outer surface pores for sustained delivery of the protein. The porous PLGA microspheres with less than 10 µm in size are prepared by electrospraying. Aqueous solutions containing fluorescein isothiocyanate-dextran or bovine serum albumin (BSA) are penetrated into the inner pores as a result of vacuum treatment, and the outer surface pores of the porous PLGA microspheres are then closed using a solvent (dimethyl sulfoxide) to ensure entrapment of the macromolecules. Confocal microscopy images confirm the presence of a large amount of the macromolecules inside the porous structure. Circular dichroism spectroscopy and release analysis reveal that BSA is entrapped without denaturation and released in a sustained manner for a period of over 2 months, respectively.


Asunto(s)
Ácido Láctico/química , Microesferas , Ácido Poliglicólico/química , Albúmina Sérica Bovina/química , Animales , Bovinos , Dicroismo Circular , Microscopía Confocal , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Porosidad , Albúmina Sérica Bovina/metabolismo
14.
Appl Opt ; 53(7): 1406-12, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-24663370

RESUMEN

In contrast to conventional x-ray food inspection systems that have difficulty in detecting low-density materials, a terahertz imaging system can even identify insects and plastics embedded in a food matrix. A reflection-mode continuous-wave terahertz imaging system was therefore developed for application to food quality inspection, which requires fast, compact, and low-cost detection. High-speed operation of the terahertz imaging system was achieved through the use of a beam-steering tool. A reasonable compromise between the spatial resolution and the scan length of an aspheric f-theta scanning lens could be achieved by optimizing the lens parameters.


Asunto(s)
Análisis de los Alimentos/instrumentación , Contaminación de Alimentos/análisis , Calidad de los Alimentos , Lentes , Imágen por Terahertz/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo
15.
Foodborne Pathog Dis ; 11(7): 574-80, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24796416

RESUMEN

A multiplex polymerase chain reaction (PCR) assay was developed for simultaneous detection of Escherichia coli O157:H7, Bacillus cereus, Vibrio parahaemolyticus, Salmonella spp., Listeria monocytogenes, and Staphylococcus aureus in various Korean ready-to-eat foods. The six specific primer pairs for multiplex PCR were selected based on the O157 antigen (rfbE) gene of E. coli O157:H7, the DNA gyrase subunit B (gyrB) gene of B. cereus, the toxin regulatory protein (toxR) gene of V. parahaemolyticus, the invasion protein A (invA) gene of Salmonella spp., the hemolysin (hly) gene of L. monocytogenes, and the thermonuclease (nuc) gene of S. aureus. The 16S rRNA gene was targeted as an internal control gene in the presence of bacterial DNA. The specificity and sensitivity assays for multiplex primer pairs were investigated by testing different strains. When this multiplex PCR assay was applied to evaluate the validity of detecting six foodborne pathogens in artificially inoculated several ready-to-eat food samples, the assay was able to specifically simultaneously detect as few as 1 colony-forming unit/mL of each pathogen after enrichment for 12 h. Their presence in naturally contaminated samples also indicates that the developed multiplex PCR assay is an effective and informative supplement for practical use.


Asunto(s)
Comida Rápida/microbiología , Contaminación de Alimentos/análisis , Reacción en Cadena de la Polimerasa Multiplex/métodos , Bacillus cereus/aislamiento & purificación , Recuento de Colonia Microbiana , Cartilla de ADN/genética , ADN Bacteriano/genética , Escherichia coli O157/aislamiento & purificación , Microbiología de Alimentos , Listeria monocytogenes/aislamiento & purificación , ARN Ribosómico 16S/genética , República de Corea , Salmonella/aislamiento & purificación , Sensibilidad y Especificidad , Staphylococcus aureus/aislamiento & purificación , Vibrio parahaemolyticus/aislamiento & purificación
16.
Micromachines (Basel) ; 15(5)2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38793172

RESUMEN

A perfluoropolyether (PFPE)-based microfluidic device with cross-junction microchannels was fabricated with the purpose of producing uniform droplets. The microchannels were developed using CO2 laser engraving. PFPE was chosen as the main material because of its excellent solvent resistance. Polyethylene glycol diacrylate (PEGDA) was mixed with PFPE to improve the hydrophilic properties of the inner surface of the microchannels. The microchannels of the polydimethylsiloxane microfluidic device had a blackened and rough surface after laser engraving. By contrast, the inner surface of the microchannels of the PFPE-PEGDA microfluidic device exhibited a smooth surface. The lower power and faster speed of the laser engraving resulted in the development of microchannels with smaller dimensions, less than 30 µm in depth. The PFPE and PFPE-PEGDA microfluidic devices were used to produce uniform water and oil droplets, respectively. We believe that such a PFPE-based microfluidic device with CO2-laser-engraved microchannels can be used as a microfluidic platform for applications in various fields, such as biological and chemical analysis, extraction, and synthesis.

17.
J Knee Surg ; 37(2): 135-141, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36638805

RESUMEN

Although the accuracy of other types of robotic systems for total knee arthroplasty (TKA) has been assessed in cadaveric studies, no investigations have been performed to evaluate this newly advanced active robotic system. Therefore, the authors aimed to analyze the accuracy of bone resection in terms of thickness and alignment in a cadaveric study. Three cadaveric specimens (six knees) and an active robotic system (CUVIS Joint, CUREXO) were used in the study. Three surgeons with different experiences in robotic TKAs performed this cadaveric study using the same robotic protocol with two different implant designs. The thickness and angle of bone resection planes obtained from the optical tracking system and the difference between resection planes and the planning data were assessed to determine accuracy. With respect to the overall resection accuracy compared to the plan, the cutting depth accuracy was within 1.0 mm mean of root mean square (RMS), and the resection angle accuracy in terms of sagittal, coronal, and axial planes was within 1.0 degree mean RMS. In contrast, no significant differences were observed between the planned and measured values in terms of the resection angles and cutting thickness. The hip-knee-ankle angle at postoperative evaluation was 0.7 degrees ± 0.7 degrees (RMS 1.0 degrees). This in vivo study suggests that the use of this newly advanced active robotic system for TKA demonstrates a high degree of accuracy in terms of resection thickness and alignment. This finding supports the clinical application of this advanced robotic system. LEVEL OF EVIDENCE: Cadaveric study, Level V.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Osteoartritis de la Rodilla , Robótica , Humanos , Artroplastia de Reemplazo de Rodilla/métodos , Articulación de la Rodilla/cirugía , Rodilla/cirugía , Cadáver , Osteoartritis de la Rodilla/cirugía
18.
Langmuir ; 29(20): 5962-7, 2013 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-23650947

RESUMEN

This paper describes the preparation of magnetic nanoparticles modified with polyethylenimine (PEI)-folic acid (PF) conjugate and their potential biomedical applications. Magnetic nanoparticles modified with (3-(2-aminoethylamino)propyltrimethoxysilane) (AEAPS) were first prepared using a ligand exchange method to provide biocompatibility and hydrophilicity, and further conjugated with PF to carry gene and enhance specific uptake into cancer cells. We demonstrated the feasibility of the multifunctional magnetic nanoparticles as contrast agents in magnetic resonance imaging (MRI) and as gene carriers for gene delivery. In vitro results revealed that the cytotoxicity of the multifunctional magnetic nanoparticles was lower compared to that of pristine magnetic nanoparticles. Furthermore, we demonstrated the specific uptake of the magnetic nanoparticles modified with PF to KB cells using WI-38 cells as comparison by confocal microscopy. The PF-modified magnetic nanoparticles can potentially be employed as theranostic nanoplatforms for targeted gene delivery to cancer cells and simultaneous magnetic resonance imaging.


Asunto(s)
Ácido Fólico/química , Nanopartículas de Magnetita/química , Polietileneimina/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ácido Fólico/farmacología , Técnicas de Transferencia de Gen , Humanos , Células KB , Imagen por Resonancia Magnética , Tamaño de la Partícula , Polietileneimina/farmacología , Relación Estructura-Actividad , Propiedades de Superficie
19.
Macromol Rapid Commun ; 34(5): 399-405, 2013 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-23303665

RESUMEN

This paper describes a facile method for the preparation of porous gelatin beads with uniform pore sizes using a simple fluidic device and their application as supporting materials for cell culture. An aqueous gelatin droplet containing many uniform toluene droplets, produced in the fluidic device, is dropped into liquid nitrogen for instant freezing and the small toluene droplets evolve into pores in the gelatin beads after removal of toluene and then freeze-drying. The porous gelatin beads exhibit a uniform pore size and monodisperse diameter as well as large open pores at the surface. Fluorescence microscopy images of fibroblast-loaded gelatin beads confirm the attachment and proliferation of the cells throughout the porous gelatin beads.


Asunto(s)
Materiales Biocompatibles/química , Técnicas de Cultivo de Célula/métodos , Porosidad
20.
Emerg Med J ; 30(7): 551-4, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22833593

RESUMEN

OBJECTIVES: Recent studies have shown that there may be an interaction between duty cycle and other factors related to the quality of chest compression. Duty cycle represents the fraction of compression phase. We aimed to investigate the effect of shorter compression phase on average chest compression depth during metronome-guided cardiopulmonary resuscitation. METHODS: Senior medical students performed 12 sets of chest compressions following the guiding sounds, with three down-stroke patterns (normal, fast and very fast) and four rates (80, 100, 120 and 140 compressions/min) in random sequence. Repeated-measures analysis of variance was used to compare the average chest compression depth and duty cycle among the trials. RESULTS: The average chest compression depth increased and the duty cycle decreased in a linear fashion as the down-stroke pattern shifted from normal to very fast (p<0.001 for both). Linear increase of average chest compression depth following the increase of the rate of chest compression was observed only with normal down-stroke pattern (p=0.004). CONCLUSIONS: Induction of a shorter compression phase is correlated with a deeper chest compression during metronome-guided cardiopulmonary resuscitation.


Asunto(s)
Reanimación Cardiopulmonar/métodos , Servicios Médicos de Urgencia/métodos , Paro Cardíaco/terapia , Masaje Cardíaco/métodos , Adulto , Análisis de Varianza , Reanimación Cardiopulmonar/educación , Reanimación Cardiopulmonar/normas , Estudios Cruzados , Servicios Médicos de Urgencia/normas , Femenino , Humanos , Masculino , Maniquíes , Simulación de Paciente , Estudios Prospectivos , Estudiantes de Medicina/psicología , Factores de Tiempo
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