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1.
J Vasc Surg Venous Lymphat Disord ; 12(2): 101678, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37708938

RESUMEN

OBJECTIVE: This study aimed to compare the efficacy of customized graduated elastic compression stockings (c-GECSs) based on lower leg parameter models with standard GECSs (s-GECSs) in patients with chronic venous disease (CVD). METHODS: In this randomized, single-blind, controlled trial, 79 patients with stage C2 or C3 CVD were assigned to one of two groups: c-GECSs or s-GECSs. The primary outcome was change to Venous Insufficiency Epidemiological and Economic Study Quality of Life (VEINES-QOL) scores at months 1, 3, and 6 as compared with baseline. Secondary outcomes included compliance with wearing ECSs, interface pressure at the smallest circumference of the ankle (point B) and the largest circumference of the calf (point C), and calf volume (CV). RESULTS: There were 13 pairs of s-GECS and 2 pairs of c-GECS that showed pressure values higher than the standard at either point B or C. The c-GECSs were significantly superior to s-GECSs in terms of score improvement at all three time points (month 1, 8.47 [95% confidence interval (CI), 7.47-9.45] vs 5.89 [95% CI, 5.00-6.78]; month 3, 9.60 [95% CI, 8.47-10.72] vs 6.72 [95% CI, 5.62-7.83]; month 6, 7.09 [95% CI, 5.93-8.24] vs 3.92 [95% CI, 2.67-5.18]; P < .0001). Besides, at month 1, the mean daily use time of the c-GECS and s-GECS groups was 10.7 and 9.5 hours, respectively (P < .05). Correlation analysis indicated a negative relationship between local high pressure and daily duration in the s-GECS group (rpb = -0.388; n = 38; P < .05). Variances in pressure were greater in the s-GECSs group. The c-GECSs showed advantage in maintaining pressure. Both c-GECSs and s-GECSs effectively reduced CV (mL), with no significant differences between groups (month 1, 90.0 [95% CI, 71.4-108.5] vs 85.0 [95% CI, 65.6-104.2]; month 3, 93.8 [95% CI, 69.7-117.8] vs 85.9 [95% CI, 65.5-106.2]; month 6, 70.8 [95% CI, 46.5-95.2]) vs 60.8 [95% CI, 44.1-77.5]). CONCLUSIONS: The c-GECSs based on individual leg parameter models significantly improved VEINES-QOL scores and provided stable and enduring pressure as compared with s-GECSs for patients with stage C2 or C3 CVD. Although both c-GECSs and s-GECSs effectively reduced CV, the superior fit and comfort of c-GECSs improved patient compliance. Hence, c-GECSs are a viable alternative for patients who have difficulty tolerating s-GECSs.


Asunto(s)
Medias de Compresión , Insuficiencia Venosa , Humanos , Calidad de Vida , Método Simple Ciego , Venas , Insuficiencia Venosa/terapia , Enfermedad Crónica
2.
Int J Neurosci ; : 1-7, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38126309

RESUMEN

OBJECTIVE: To evaluate the diagnostic value of ultrasensitive C-reactive protein (hs-CRP) and homocysteine (Hcy) for cerebral infarction. METHODS: 260 elderly patients with cerebral infarction were recruited and assigned to the stroke group, and 60 healthy elderly were identified as controls and included in the normal group. Serum samples of all subjects were collected at the time of admission for the determination of hs-CRP and Hcy levels. RESULTS: Patients with cerebral infarction exhibited significantly higher hs-CRP and Hcy levels than healthy controls. the patients were then categorized into mild-moderate and moderate-severe groups according to the National Institutes of Health Stroke Scale (NIHSS) score. No significant association was identified between Hcy levels and infarction severity, while more severe infarction was potentially related to higher hs-CRP levels, as evidenced by the higher hs-CRP levels observed in patients with moderate-severe infarction versus a milder severity. Patients with disease recurrence within 2 years were also included in a recurrence group, while those without recurrence were in a non-recurrence group. Results showed that patients with or without disease recurrence had similar hs-CRP and Hcy levels. CONCLUSION: In elderly patients with cerebral infarction, serum hs-CRP, and Hcy levels are potentially promising markers for the diagnosis of stroke, assessment of stroke severity, and prediction of functional recovery. hs-CRP provides more benefits in diagnosing cerebral infarction, and Hcy is more conducive to the assessment of stroke severity and prediction of functional recovery. Combined detection of the two indices did not offer additional benefits in diagnostic and predictive efficacy.

3.
ACS Appl Mater Interfaces ; 14(30): 34714-34721, 2022 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-35876495

RESUMEN

Harvesting low-grade heat by an ionic hydrogel thermoelectric generator (ITEG) into useful electricity is promising to power flexible electronics. However, the poor environmental tolerance of the ionic hydrogel limits its application. Herein, we demonstrate an ITEG with high thermoelectric properties, as well as excellent capabilities of water retention, freezing resistance, and self-regeneration. The obtained ITEG can maintain the original water content at ambient conditions (302 K, 65% relative humidity (RH)) for 7 days and keep unfreezing at a low temperature (253 K). It can even be self-regenerated and recovered to its original state after a water loss in high-temperature conditions. Furthermore, a high ionic Seebeck coefficient of 11.3 mV K-1 and an impressive power density of 167.90 mW m-2 are achieved under a temperature difference of 20 K. A high power density of 60.00 mW m-2 can also be maintained even at 258 K. After drying and regeneration, ITEG-re could even exhibit a higher ionic Seebeck coefficient of 11.8 mV K-1. Successful lighting of light-emitting diodes (LEDs) and charging of capacitors demonstrate the great potential of ITEG to provide continuous energy supply for powering flexible electronics.

4.
Nanoscale ; 12(3): 1281-1306, 2020 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-31912063

RESUMEN

Synthetic materials and biomaterials with elastic moduli lower than 10 MPa are generally considered as soft materials. Research studies on soft materials have been boosted due to their intriguing features such as light-weight, low modulus, stretchability, and a diverse range of functions including sensing, actuating, insulating and transporting. They are ideal materials for applications in smart textiles, flexible devices and wearable electronics. On the other hand, benefiting from the advances in materials science and chemistry, novel soft materials with tailored properties and functions could be prepared to fulfil the specific requirements. In this review, the current progress of soft materials, ranging from materials design, preparation and application are critically summarized based on three categories, namely gels, foams and elastomers. The chemical, physical and electrical properties and the applications are elaborated. This review aims to provide a comprehensive overview of soft materials to researchers in different disciplines.

5.
Nature ; 575(7783): 453-454, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31748719
6.
Diabetol Metab Syndr ; 11: 55, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31312258

RESUMEN

BACKGROUND: Transcription factor 7-like 2 (TCF7L2), which previously known as TCF-4, is a major form of transcription factor involved in the downstream WNT signaling and exhibits the strongest association to diabetes susceptibility. Although we still do not know mechanistically how TCF7L2 exerts its physiological functions on pancreatic endocrine cells, it had been suggested that TCF7L2 may directly affect ß-cell function by regulating the activation of PI3K/AKT signaling pathway. METHODS: MIN6 cells were transfected with TCF7L2 knockdown virus or lenti-TCF7L2 virus for 48 h to evaluate the contribution of TCF7L2 to the PI3K/AKT signaling pathway and pancreatic ß-cell function. This was confirmed by measuring the expression of PI3K p85 and p-Akt by western blotting and insulin secretion by enzyme-linked immunosorbent assay (ELISA), respectively. Chromatin immunoprecipitation (ChIP) and polymerase chain reaction (PCR) experiments were performed to explore the genomic distribution of TCF7L2-binding sites in the promoter of PIK3R1, the affinity between which was analyzed by the luciferase reporter assay. RESULTS: In the present study, we strikingly identified that TCF7L2 could profoundly inhibit the expression of PIK3R1 gene and its encoding protein PI3K p85, which then could lead to the activation of PI3K/AKT signaling and stimulate insulin secretion in pancreatic ß-cells. However, the integrity and stability of evolutionarily conserved TCF7L2-binding motif plays a very crucial role in the binding events between transcription factor TCF7L2 and its candidate target genes. We also found that the affinity of TCF7L2 to the promoter region of PIK3R1 alters upon the specific binding sites, which further provides statistical validation to the necessity of TCF7L2-binding motif. CONCLUSIONS: This study demonstrated that TCF7L2 is closely bound to the specific binding regions of PIK3R1 promoter and prominently controls the transcription of its encoding protein p85, which further affects the activation of PI3K/AKT signaling pathway and insulin secretion.

7.
Adv Healthc Mater ; 6(12)2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28547895

RESUMEN

Physiological temperature varies temporally and spatially. Accurate and real-time detection of localized temperature changes in biological tissues regardless of large deformation is crucial to understand thermal principle of homeostasis, to assess sophisticated health conditions, and further to offer possibilities of building a smart healthcare and medical system. Additionally, continuous temperature mapping in flexible and stretchable formats opens up many other potential areas, such as artificially electronic skins and reflection of emotional changes. This review exploits a comprehensive investigation onto recent advances in flexible temperature sensors, stretchable sensor networks, and platforms constructed in soft and compliant formats for wearable physiological monitoring. The most recent examples of flexible temperature sensors are first discussed regarding to their materials, structures, electrical and mechanical properties; temperature sensing network technologies in new materials and structural designs are then presented based on platforms comprised of multiple physical sensors and stretchable electronics. Finally, wearable applications of the sensing network are described, such as detection of human activities, monitoring of health conditions, and emotion-related bodily sensations. Conclusions are made with emphasis on critical issues and new trends in the field of wearable temperature sensor network technologies.


Asunto(s)
Redes de Comunicación de Computadores , Monitoreo Fisiológico/métodos , Temperatura , Dispositivos Electrónicos Vestibles , Humanos , Docilidad
8.
Int J Ophthalmol ; 9(5): 707-12, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27275426

RESUMEN

AIM: To identify the contribution of CDKAL1 to the development of diabetic retinopathy (DR) in Chinese population. METHODS: A case-control study was performed to investigate the genetic association between DR and polymorphic variants of CDKAL1 in Chinese Han population with type 2 diabetes mellitus (T2DM). A well-defined population with T2DM, consisting of 475 controls and 105 DR patients, was recruited. All subjects were genotyped for the genetic variant (rs10946398) of CDKAL1. Genotyping was performed by iPLEX technology. The association between rs10946398 and T2DM was assessed by univariate and multivariate logistic regression (MLR) analysis. RESULTS: There were significant differences in C allele frequencies of rs10946398 (CDKAL1) between control and DR groups (45.06% versus 55.00%, P<0.05). The rs10946398 of CDKAL1 was found to be associated with the increased risk of DR among patients with diabetes. CONCLUSION: Our findings suggest that rs10946398 of CDKAL1 is independently associated with DR in a Chinese Han population.

9.
Nanoscale ; 7(5): 1627-34, 2015 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-25553809

RESUMEN

The dissociation of carbon feedstock is a crucial step for understanding the mechanism of graphene chemical vapor deposition (CVD) growth. Using first-principles calculations, we performed a comprehensive theoretical study for the population of various active carbon species, including carbon monomers and various radicals, CHi (i = 1, 2, 3, 4), on four representative transition-metal surfaces, Cu(111), Ni(111), Ir(111) and Rh(111), under different experimental conditions. On the Cu surface, which is less active, the population of CH and C monomers at the subsurface is found to be very high and thus they are the most important precursors for graphene CVD growth. On the Ni surface, which is more active than Cu, C monomers at the subsurface dominate graphene CVD growth under most experimental conditions. In contrast, on the active Ir and Rh surfaces, C monomers on the surfaces are found to be very stable and thus are the main precursors for graphene growth. This study shows that the mechanism of graphene CVD growth depends on the activity of catalyst surfaces and the detailed graphene growth process at the atomic level can be controlled by varying the temperature or partial pressure of hydrogen.

10.
Eur J Med Res ; 20: 3, 2015 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-25573672

RESUMEN

BACKGROUND: Genome-wide association studies (GWAS) have reported that the polymorphism rs5219 of the potassium inwardly rectifying channel, subfamily J, member 11 (KCNJ11) is associated with type 2 diabetes mellitus (T2DM). Given that diabetic retinopathy (DR) is one of the most common microvascular complications of T2DM, GWAS have identified a number of potential susceptibility genes for DR. However, only a fraction of them have been replicated in different studies and show consistent genetic associations with the occurrence of DR. The aim of the present study was to investigate whether common variants of KCNJ11 confer DR in a cohort of the Chinese Han population. METHODS: A case-control study of 580 T2DM patients, including 105 T2DM with DR and 475 T2DM without DR was performed. A single nucleotide polymorphism (SNP) of KCNJ11 (rs5219) was genotyped, and its association with DR was explored using a dominant genetic model. Genotyping was performed by iPLEX technology. Univariate and multivariate logistic regression (MLR) analysis controlling for confounders was conducted to evaluate the association between rs5219 and DR. RESULTS: The A allele frequency of rs5219 was significantly higher in DR patients than that in the patients without DR (49.01% versus 38.68%, P <0.05). We found the minor A allele could increase the risk to develop DR (ORint = 1.58, 95% CI: 1.139 to 2.192 for allele and P = 0.006, ORint =1.607, 95% CI: 1.267 to 2.038 for genotype and P <0.001) in the Chinese Han population. CONCLUSIONS: Our findings provided evidence that KCNJ11 was associated with DR in Chinese Han patients with T2DM.


Asunto(s)
Retinopatía Diabética/genética , Polimorfismo de Nucleótido Simple , Canales de Potasio de Rectificación Interna/genética , Anciano , Estudios de Casos y Controles , China , Femenino , Humanos , Masculino , Persona de Mediana Edad
11.
Proc Math Phys Eng Sci ; 470(2171): 20140472, 2014 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-25383032

RESUMEN

This paper reports fabric circuit boards (FCBs), a new type of circuit boards, that are three-dimensionally deformable, highly stretchable, durable and washable ideally for wearable electronic applications. Fabricated by using computerized knitting technologies at ambient dry conditions, the resultant knitted FCBs exhibit outstanding electrical stability with less than 1% relative resistance change up to 300% strain in unidirectional tensile test or 150% membrane strain in three-dimensional ball punch test, extraordinary fatigue life of more than 1 000 000 loading cycles at 20% maximum strain, and satisfactory washing capability up to 30 times. To the best of our knowledge, the performance of new FCBs has far exceeded those of previously reported metal-coated elastomeric films or other organic materials in terms of changes in electrical resistance, stretchability, fatigue life and washing capability as well as permeability. Theoretical analysis and numerical simulation illustrate that the structural conversion of knitted fabrics is attributed to the effective mitigation of strain in the conductive metal fibres, hence the outstanding mechanical and electrical properties. Those distinctive features make the FCBs particularly suitable for next-to-skin electronic devices. This paper has further demonstrated the application potential of the knitted FCBs in smart protective apparel for in situ measurement during ballistic impact.

12.
Diabetol Metab Syndr ; 6(1): 107, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25302081

RESUMEN

BACKGROUND: Peroxisome proliferator-activated receptor gamma coactivator-1α (PPARGC1A/ PGC-1α) is a ligand-activated transcription factor belonging to the nuclear hormone receptor superfamily. The activity of PGC-1α or genetic variations in the gene encoding the enzyme may contribute to individual variations in mitochondrial function and insulin resistance or diabetes. The objective of this study was to assess the extent to which PPARGC1A (rs8192678) and serum uric acid (UA) and its interaction impact on T2DM susceptibility in Chinese Han population. METHOD: We conducted a study in a cohort that included 1166 T2DM patients and 1135 controls, and was genotyped for the presence of the PPARGC1A rs8192678 polymorphisms. Genotyping was performed by iPLEX technology. The association between rs8192678 or UA and T2DM was assessed by univariate and multivariate logistic regression (MLR) analysis controlling for confounders. The interaction between rs8192678 and UA for T2DM susceptibility was also assessed by MLR analysis. RESULTS: The generalized linear regression analysis failed to show an association between the PPARGC1A rs8192678 polymorphisms and T2DM. Interestingly, the present study provided data suggesting that the minor A-allele of PPARGC1A (rs8192678) had a protective effect against T2DM in subjects with higher level of UA (ORint =1.50 95% CI: 1.06-2.12 for allele and P = 0.02, ORint =1.63 95% CI: 1.17-2.26 for genotype and P = 0.004). CONCLUSION: The combination of higher level of UA and PPARGC1A (rs8192678) was an independent predictor for T2DM.

13.
Eur J Med Res ; 19: 40, 2014 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-25062844

RESUMEN

BACKGROUND: The objective of this study was to systematically evaluate the contribution of the insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) to type 2 diabetes mellitus (T2DM) and its interaction with obesity to T2DM susceptibility. METHODS: To clarify whether IGF2BP2 is an independent risk factor for T2DM in Chinese population, we conducted a study with a total of 2,301 Chinese Han subjects, including 1,166 T2DM patients and 1,135 controls, for the genotype of a most common and widely studied polymorphism-rs4402960 of IGF2BP2. Genotyping was performed by iPLEX technology. Gene and environment interaction analysis was performed by using multiple logistic regression models. RESULTS: The repeatedly confirmed association between IGF2BP2 (rs4402960) and T2DM had not been replicated in this cohort (P = 0.182). Interestingly, we found that obese subjects (body mass index (BMI) ≥ 28.0 kg/m2) bearing the minor A allele had an increased risk to develop T2DM (P = 0.008 for allele analysis and P < 0.001 for genotype analysis). CONCLUSIONS: The present study provided data suggesting that the wild C allele of IGF2BP2 (rs4402960) had a protective effect against T2DM in obese subjects of Chinese Han population.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Estudios de Asociación Genética , Obesidad/genética , Proteínas de Unión al ARN/genética , Adulto , Anciano , Pueblo Asiatico , China , Diabetes Mellitus Tipo 2/patología , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Obesidad/patología , Polimorfismo de Nucleótido Simple , Factores de Riesgo
14.
Adv Mater ; 26(31): 5310-36, 2014 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-24943999

RESUMEN

Fiber-based structures are highly desirable for wearable electronics that are expected to be light-weight, long-lasting, flexible, and conformable. Many fibrous structures have been manufactured by well-established lost-effective textile processing technologies, normally at ambient conditions. The advancement of nanotechnology has made it feasible to build electronic devices directly on the surface or inside of single fibers, which have typical thickness of several to tens microns. However, imparting electronic functions to porous, highly deformable and three-dimensional fiber assemblies and maintaining them during wear represent great challenges from both views of fundamental understanding and practical implementation. This article attempts to critically review the current state-of-arts with respect to materials, fabrication techniques, and structural design of devices as well as applications of the fiber-based wearable electronic products. In addition, this review elaborates the performance requirements of the fiber-based wearable electronic products, especially regarding the correlation among materials, fiber/textile structures and electronic as well as mechanical functionalities of fiber-based electronic devices. Finally, discussions will be presented regarding to limitations of current materials, fabrication techniques, devices concerning manufacturability and performance as well as scientific understanding that must be improved prior to their wide adoption.


Asunto(s)
Equipos y Suministros Eléctricos , Textiles , Conductividad Eléctrica , Nanotecnología/métodos
15.
Beijing Da Xue Xue Bao Yi Xue Ban ; 42(5): 498-502, 2010 Oct 18.
Artículo en Chino | MEDLINE | ID: mdl-20957003

RESUMEN

OBJECTIVE: To investigate the association between the NINJ2 gene rs11833579 polymorphism and stroke in Han Chinese population. METHODS: This study was a population-based cross-sectional case-control study. Polymerase chain reaction-restriction fragment length polymorphism (RFLP) and sequencing were used for the detection of NINJ2 genotypes in 790 patients with stroke (679 ischemic stroke) which were Han Chinese population from Fangshan First Hospital and 811 controls which were healthy Han Chinese population without family history of stroke in Fangshan district rural area. RESULTS: In rs11833579 locus of the NINJ2 gene, the frequencies of GG genotype and allele G were higher in ischemic stroke patients than that in controls (P<0.001). The frequency of allele G of the NINJ2 gene was higher in cerebral hemorrhage patients than that in controls (P=0.005). Genotype had little effect on the glucose, total cholesterol and triglyceride. CONCLUSION: There is significant association between rs11833579 site polymorphism of the NINJ2 gene and risk for stroke in Han Chinese population from Fangshan district.


Asunto(s)
Moléculas de Adhesión Celular Neuronal/genética , Predisposición Genética a la Enfermedad , Polimorfismo Genético/genética , Accidente Cerebrovascular/genética , Anciano , Estudios de Casos y Controles , Hemorragia Cerebral/genética , Infarto Cerebral/genética , China/etnología , Estudios Transversales , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo de Longitud del Fragmento de Restricción
16.
ACS Appl Mater Interfaces ; 2(6): 1707-13, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20527778

RESUMEN

Nanocomposites of chitosan and graphene oxide are prepared by simple self-assembly of both components in aqueous media. It is observed that graphene oxide is dispersed on a molecular scale in the chitosan matrix and some interactions occur between chitosan matrix and graphene oxide sheets. These are responsible for efficient load transfer between the nanofiller graphene and chitosan matrix. Compared with the pure chitosan, the tensile strength, and Young's modulus of the graphene-based materials are significantly improved by about 122 and 64%, respectively, with incorporation of 1 wt % graphene oxide. At the same time, the elongation at the break point increases remarkably. The experimental results indicate that graphene oxide sheets prefer to disperse well within the nanocomposites.


Asunto(s)
Quitosano/química , Grafito/química , Nanocompuestos/química , Nanotecnología/métodos , Óxidos/química , Módulo de Elasticidad , Ensayo de Materiales , Microscopía de Fuerza Atómica/métodos , Microscopía Electrónica de Transmisión/métodos , Modelos Químicos , Espectroscopía Infrarroja por Transformada de Fourier , Resistencia a la Tracción , Difracción de Rayos X
17.
ChemMedChem ; 5(4): 559-66, 2010 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-20209565

RESUMEN

A homologous set of 9,9-dialkyl-4,5-diazafluorene compounds were prepared by alkylation of 4,5-diazafluorene with the appropriate alkyl bromide and under basic conditions. The structures of these simple organic compounds were confirmed by spectroscopic techniques (FTIR, NMR, and FABMS). Their biological effects toward a panel of human carcinoma cells, including Hep3B hepatocellular carcinoma, MDAMB-231 breast carcinoma, and SKHep-1 hepatoma cells, were investigated; a structure-activity correlation was established with respect to the length of the alkyl chain and the fluorene ring structure. The relationship between the mean potency [log(1/IC(50))] and alkyl chain length was systematically studied. The results show that compounds with butyl, hexyl, and octyl chains exhibit good growth inhibitory effects toward these three human carcinoma cell lines, and the 9,9-dihexyl-4,5-diazafluorene further exhibits antitumor activity in athymic nude mice Hep3B xenograft models. For the structurally related dialkylfluorenes that lack the diaza functionality, in vitro cytotoxicity was not observed at clinically relevant concentrations.


Asunto(s)
Antineoplásicos/síntesis química , Carcinoma/tratamiento farmacológico , Fluorenos/química , Animales , Antineoplásicos/química , Antineoplásicos/toxicidad , Neoplasias de la Mama/tratamiento farmacológico , Carcinoma Hepatocelular/tratamiento farmacológico , Línea Celular Tumoral , Femenino , Fluorenos/síntesis química , Fluorenos/toxicidad , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Ratones , Ratones Desnudos , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de Xenoinjerto
18.
Nanoscale Res Lett ; 4(7): 613-7, 2009 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-20596414

RESUMEN

A conductive polymer, poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), was modified with dimethyl sulfoxide (DMSO) in solution state, together with sub-sequential thermal treatment of its spin-coated film. The electrical conductivity increased by more than three orders of magnitude improvement was achieved. The mechanism for the conductivity improvement was studied at nanoscale by particle size analysis, field emission scanning electron microscopy (FESEM), and X-ray photoelectron spectroscopy (XPS). Smaller particle size was observed, resulting in larger contact area and better electrical conductive connections. Connection of conductive PEDOT increased on the surface of the PEDOT:PSS particles, which promoted high conductivity. Flexible anodes based on the modified PEDOT:PSS were fabricated. Flexible organic light-emitting diodes (FOLED) based the polymeric anodes have a comparable performance to those on indium-tin-oxide (ITO) anodes.

19.
Nanotechnology ; 19(14): 145201, 2008 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-21817753

RESUMEN

Flexible organic light-emitting diodes (FOLEDs) are facing mechanical issues arising from failure of the indium-tin oxide (ITO) films fabricated on flexible substrates. Polymeric nanocomposite anodes were fabricated by including single-wall carbon nanotubes (SWCNTs) in aqueous poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS). The conductivity, transmittance and flexibility of the polymeric nanocomposite anode were characterized. The polymeric nanocomposite anodes fabricated on a poly(ethylene terephthalate) (PET) substrate exhibited superior bending properties to ITO anodes on PET. The FOLEDs fabricated on the polymeric nanocomposite anodes had a low turn-on voltage and higher luminous intensity than those fabricated on ITO/PET anodes. This flexible nanocomposite polymeric anode is a very promising for fully FOLEDs and other optoelectronics.

20.
Biomacromolecules ; 7(10): 2719-21, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17025344

RESUMEN

A novel chitosan fiber core/gold shell structural organic-inorganic composite was presented via a facile and eco-friendly approach. The chitosan fiber and gold/chitosan composites were characterized with the assistance of scanning electron microscopy and transmission electron microscopy observations. The chitosan fibers used in this study were 50 nm to 5 microm in diameter and up to hundreds of micrometers in length. The gold shells were typically 20-50 nm in depth, and their lattice fringes obliquely intersecting at an angle of 60 degrees were displayed. The formation mechanism of the as-fabricated chitosan fiber core with gold as the shell structural composites was also schematically discussed.


Asunto(s)
Materiales Biocompatibles/química , Biotecnología/métodos , Quitosano/química , Oro/química , Nanopartículas/química , Adsorción , Aniones , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Nanotecnología/métodos , Tamaño de la Partícula
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