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1.
AMIA Annu Symp Proc ; 2017: 1411-1420, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29854210

RESUMEN

Research data warehouses integrate research and patient data from one or more sources into a single data model that is designed for research. Typically, institutions update their warehouse by fully reloading it periodically. The alternative is to update the warehouse incrementally with new, changed and/or deleted data. Full reloads avoid having to correct and add to a live system, but they can render the data outdated for clinical trial accrual. They place a substantial burden on source systems, involve intermittent work that is challenging to resource, and may involve tight coordination across IT and informatics units. We have implemented daily incremental updating for our i2b2 data warehouse. Incremental updating requires substantial up-front development, and it can expose provisional data to investigators. However, it may support more use cases, it may be a better fit for academic healthcare IT organizational structures, and ongoing support needs appear to be similar or lower.


Asunto(s)
Investigación Biomédica/organización & administración , Data Warehousing/métodos , Bases de Datos como Asunto/organización & administración , Humanos
2.
Dent Mater ; 33(1): 12-22, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27745776

RESUMEN

OBJECTIVE: The object is to find a functional one-dimensional nanofibrous filler for composite resin, which is able to provide both efficient reinforcement and high antibacterial activity. METHODS: Hydroxyapatite (HA) nanowires were synthesized via hydrothermal technique using calcium oleate as the precursor. Polydopamine (PDA)-coated HA (HA-PDA) nanowires were prepared by soaking HA nanowires in dopamine (DA) aqueous solution. Silver nanoparticles (AgNPs)-laden HA (HA-PDA-Ag) nanowires were prepared via reduction reaction by adding silver nitrate and glucose into HA-PDA suspensions in DI water. The resulted HA-PDA-Ag nanowires were then mixed into Bis-GMA/TEGDMA (50/50, w/w) at 4-10wt.%, thermal-cured, and submitted to characterizations including mechanical properties, interfacial adhesion between filler and resin matrix, distribution of HA nanowires and AgNPs, as well as silver ion release, cytotoxicity and antibacterial activity. RESULTS: HA-PDA-Ag nanowires were readily obtained and the loading amounts of AgNPs could be controlled by adjusting the feeding doses of silver nitrate and HA-PDA nanowires. Benefiting from the PDA surface layer, HA-PDA-Ag nanowires could disperse well in composite resin and form good interfacial adhesion with the resin matrix. In comparison with neat resin, significant increases in flexural strength and modulus of cured composites were achieved at the addition amounts of HA-PDA-Ag nanowires being 6-8wt.%. The distribution of AgNPs was homogeneous throughout the resin matrix in all designs, which endowed the composites with high antibacterial activity against streptococcus mutans. Continuous silver ion release from composites was detected, however, it was determined the composites would have insignificant cytotoxicity based on the proliferation of L929 fibroblasts in extracts of HA-PDA-Ag nanowires. SIGNIFICANCE: The finding proved that HA-PDA-Ag nanowires could serve as functional nanofillers for composite resins, which should help much in developing materials for satisfactory long-term clinical restorations.


Asunto(s)
Durapatita , Nanopartículas del Metal , Nanocables , Plata , Resinas Compuestas , Humanos , Ensayo de Materiales
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(7): 2059-65, 2016 Jul.
Artículo en Chino | MEDLINE | ID: mdl-30035882

RESUMEN

Near-infrared quantum dots have unique optical properties, such as high fluorescence quantum yield, long fluorescent life, tunable fluorescence emission wavelength, half peak width and large stokes shift, resisting light bleaching etc. The advantage of "near infrared biological window" gives them great potential application value in biological fluorescent tags, solar cells, quantization calculation, photocatalysis, chemical analysis, food detection, vivo imaging and other fields. At present, the luminescence mechanism research of near-infrared quantum dots is still not comprehensive enough. In this paper, the luminescent principle of three different types of near-infrared quantum dots is summarized, including core/shell structure quantum dots (CdTe/CdSe, CdSe/CdTe/ZnSe, etc), ternary quantum dots (Cu-In-Se, CuInS2, etc) and doped quantum dots (Cu∶InP, etc). The luminescence mechanism of Type Ⅱ core/shell structure is most likely to attribute to the interband recombination luminescence, the ternary structure of quantum dots light emitting mechanism is considered to be due to the intrinsic structure defects, and the luminescence mechanism of doped quantum dots is deemed to result from the impurity defects. The existing problems of near-infrared luminescent principle of quantum dots are also discussed and their development tendency is explored t in this review. A systematic study of luminescence mechanism of near-infrared quantum dots will not only help to understand the luminescent properties of near infrared quantum dots, but also contribute to improve the synthesis methods of quantum dots with similarly high quality.

4.
Colloids Surf B Biointerfaces ; 123: 753-61, 2014 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-25454665

RESUMEN

Substrate-controlled mineralization from simulated body fluid (SBF) has been studied as a model for biomineralization and for the synthesis of bioinspired hybrid materials. The mineralization procedure is complex and the features of final minerals are affected by many factors. Surface functional groups are among them and play important roles in inducing nucleation, crystal growth and transformation. In this study, multi-walled carbon nanotubes (MWCNTs) were surface-modified with poly(acrylic acid), polyacrylamide or poly(hydroxyethyl methylacrylate), and used as templates for biomineralization. The polymer coating was gained via photo-initiated polymerization of monomers and adsorption of polymer chains onto MWCNTs in solution. Then, the modified MWCNTs with different surface functional groups were incubated in 1.5 times SBF for different times to compare the effect of carboxyl, acylamino and hydroxyl group on calcium phosphate formation. The study involved various characterizations such as morphology observation, weight increase, chemical and crystal structures of deposited minerals at different soaking time points. In all cases, carbonated calcium-deficient hydroxyapatite (CDHA) was identified after 7 days immersion. The continuously growing mineral crystals would wrap MWCNTs into spherical composite particles ultimately. However, the rates of nucleation and crystal growth depended on the type of surface functional groups, in an order of COOH>CONH2>OH. And their different charge characteristics led to different Ca/P ratios in initially formed minerals. It revealed that acylamino group, which demonstrated the lowest Ca/P ratio in nucleation stage, was helpful to obtain c-axis preferentially oriented morphology resembling the HA structure in natural bone tissue.


Asunto(s)
Nanotubos de Carbono/química , Polímeros/química , Durapatita/química , Nanotubos de Carbono/ultraestructura
5.
Cancer Biother Radiopharm ; 27(9): 530-4, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23062195

RESUMEN

Poly I:C is a synthetic dsRNA that can imitate a viral infection and elicit host immune responses by triggering specific pattern-recognition receptors (PRRs) such as toll-like receptor 3 and retinoic acid inducible gene I(RIG-I)-like receptors, including RIG-I and melanoma differentiation-associated gene 5. Activation of these PRRs by poly I:C triggers a signal transduction cascade that results in the activation of NF-κB and production of type I interferon. Poly I:C has been used as a vaccine adjuvant for cancer immunotherapy for several decades. Evidence from recent studies indicates that poly I:C can directly induce apoptosis in several types of tumor cells, thus providing a new therapeutic approach for cancer treatment. However, the molecular mechanism underlying the induction of apoptosis by poly I:C is still unclear. In this review, we summarize the current knowledge of poly I:C-induced tumor cell apoptosis, focusing on the key molecules and pathways involved in this process.


Asunto(s)
Apoptosis/efectos de los fármacos , Inductores de Interferón/farmacología , Poli I-C/farmacología , Receptores de Reconocimiento de Patrones/metabolismo , Animales , Apoptosis/fisiología , Humanos , Transducción de Señal/efectos de los fármacos
6.
Huan Jing Ke Xue ; 32(11): 3372-8, 2011 Nov.
Artículo en Chino | MEDLINE | ID: mdl-22295637

RESUMEN

Well-aligned and uniform titanium dioxide nanotube arrays were fabricated in situ on titanium substrate by electrochemical anodic oxidation. SEM images indicate that the TiO2 nanotubes are well organized into high-density uniform arrays,with diameter ranging in size from 70 to 100 nm. The XRD patterns show that the sample fabricated by anodic oxidation is amorphous without being annealed. As the 500 degrees C annealed sample crystallized in the anatase phase, which is in good photocatalytic activity. In quartz glass reactor, the photoelectrocatalytic degradation of MB in aqueous solutions as well as the effect factors and then to 0.1 mol/L NaCl as the electrolyte, under with in oxygen atmospheres annealed the applied bias is 0.5 V and has a pH = 3.25, light intensity is 1 000 microW/cm2 and the surface area of nano-tube array film conditions, will help to improve the TiO2 nanotubes array film photoelectrocatalysis degradation of MB degradation efficiency is 99.56%. The results of EIS analyses revealed that the surface reaction step was the only rate limiting step either for the photoelectrocatalytic process. The extra bias potential could decrease the values of the electron-transfer resistance and increase the separation efficiency of photogenerated electron-hole pairs.


Asunto(s)
Azul de Metileno/química , Nanotubos/química , Procesos Fotoquímicos , Fotólisis , Titanio/química , Catálisis , Técnicas Electroquímicas , Contaminantes Ambientales/química , Contaminantes Ambientales/aislamiento & purificación , Azul de Metileno/aislamiento & purificación , Oxígeno/química
7.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-264384

RESUMEN

<p><b>OBJECTIVE</b>To study the mechanism of sensitivity variation to cisplatin caused by nm23-H1.</p><p><b>METHODS</b>The samles was divided into two groups: Tca8113 group and Tca8113/nm23-H1 group. Using MTT and flow cytometer, the changes of cell mortality rate, apoptosis and mitochondrial membrane potential were detected. By VG PQ Excell, the changes of the intracellular platinum were detected.</p><p><b>RESULTS</b>In vitro the cell mortality rate and apoptosis were increased in Tca8113/nm23-H1 group, comparing with Tea8113 group. Mitochondrial membrane potential was decreased in Tca8113/nm23-H1 group. The intracellular platinum was increased significantly in Tca8113/nm23-H1 group. This effect could be inhibited by oubain which was an inhibitor of Na+/K+-ATP.</p><p><b>CONCLUSION</b>nm23-H1 can increase the sensitivity of cisplatin on Tca8113 cell line. The mitochondrial membrane potential was decreased by nm23-H1 so that intracellular platinum was increased and finally increased the apoptosis or necrosis.</p>


Asunto(s)
Humanos , Apoptosis , Línea Celular , Línea Celular Tumoral , Cisplatino , Técnicas In Vitro , Nucleósido Difosfato Quinasas NM23 , Transfección
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(11): 1857-60, 2005 Nov.
Artículo en Chino | MEDLINE | ID: mdl-16499064

RESUMEN

The nano-photochemical reaction of polyethyelene glycol (PEG)-Au3+ was studied by resonance scattering and absorption spectrophotometry, and transmission electron microscopy. Influence of various factors on the preparation of gold nanoparticles was considered. There is a correlation between the molecular mass of PEG and the size of gold nanoparticles. A new photochemical method was proposed for the preparation of gold nanoparticles in size of 6-60 nm, using different molecular mass of PEG. The cause of obtaining gold nanoparticle with different size is the different space effect and hydrophobic property of PEG. A reasonable nano-reaction mechanism was developed.

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