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1.
Small ; 16(30): e2001686, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32521107

RESUMEN

Herein, a supermolecular-scale cage-confinement pyrolysis strategy is proposed to build two dielectric electromagnetic wave absorbents, in which MoO2 nanoparticles are sandwiched uniformly between porous carbon shells and reduced graphene oxide (RGO). Both sandwich structures are derived from hybrid hydrogels doped by two different crosslinkers (with/without oxygen bridge), which can precisely confine Mo source (e.g., PMo12 ). Without adding magnetic components, both absorbents exhibit excellent low frequency absorption performance in combination with electrically tunable ability and enhanced reflection loss value, which is superior over other relative 2D dielectric absorbers and satisfies the requirements of portable electronics. Notably, introducing oxygen bridges in the crosslinker generates a more stable confining configuration, which in turn renders its corresponding derivative exhibiting an extra multifrequency electromagnetic wave absorption trait. The intrinsic electromagnetic wave adjustment mechanism of the ternary hybrid absorbent is also explored. The result reveals that the elevated electromagnetic wave absorbing property is attributed to moderate attenuation constant and glorious impendence matching. The cage-confinement pyrolysis route to fabricate 2D MoO2 -based dielectric electromagnetic wave absorbents opens a new path for the design of electromagnetic wave absorbents used in multi/low frequency.

2.
Tumour Biol ; 36(1): 437-46, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25266797

RESUMEN

Kaposi's sarcoma (KS) is a multicentric angioproliferative tumor of mesenchymal origin. The molecular and biologic aspects of KS are not fully understood. MicroRNAs are non-protein-coding small RNAs in the size range 19-25 nucleotides (nt) that play important roles in biological processes, including cellular differentiation, proliferation, and death. We performed a miRNA microarray analysis by detecting six paired KS and matched adjacent healthy tissues using the 7th generation of miRCURY(TM) LNA Array (v.18.0) (Exiqon) containing 3100 capture probes. We selected 10 significant differentially expressed miRNAs, which were confirmed by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) in 18 paired KS and matched adjacent healthy tissue specimens. We also investigated the associations between clinical features and miRNA expression. Among the 3100 human miRNA probes in the microarrays, we identified 170 differentially expressed miRNAs (69 upregulated and 101 downregulated miRNAs) in KS versus adjacent healthy tissues. Among the most significantly upregulated miRNAs were miR-126-3p, miR-199a-3p, miR-16-5p, and the 13 KSHV-related miRNAs. The most significantly downregulated miRNAs included miR-125b-1-3p and miR-1183. Eight upregulated miRNAs, miR-181b-5p, miR-199a-3p, miR-15a-5p, miR-126-3p, miR-1297, kshv-miR-k12-12-3p, kshv-miR-k12-1-5p, and miR-16-5p, and two downregulated miRNAs, miR-125b-1-3p and miR-1183, were confirmed by qRT-PCR in 18 paired KS samples. The qRT-PCR results for 10 miRNAs were consistent with our microarray results. The miR-125b-1-3p and miR-16-5p had statistically significant associations with HHV-8 and HIV infections in KS. The results of miRNA profiling showed that KS appears to have unique expression patterns when compared with paired adjacent healthy tissues, suggesting that deregulation of miRNAs plays an important role in the progression of KS. These differentially expressed miRNAs may provide novel diagnostic and prognostic tools.


Asunto(s)
MicroARNs/genética , Sarcoma de Kaposi/metabolismo , Neoplasias Cutáneas/metabolismo , Transcriptoma , Adulto , Anciano , Femenino , Infecciones por VIH/genética , Infecciones por VIH/metabolismo , Humanos , Masculino , MicroARNs/metabolismo , Persona de Mediana Edad , Sarcoma de Kaposi/genética , Sarcoma de Kaposi/virología , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/virología
3.
Nanomaterials (Basel) ; 14(13)2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38998704

RESUMEN

With the widespread use of electronic devices, electromagnetic interference (EMI) has become an increasingly severe issue, adversely affecting device performance and human health. Carbon nanotubes (CNTs) are recognized for their electrical conductivity, flexibility, and stability, making them promising candidates for EMI shielding applications. This research developed hierarchical porous-structured CNT/carbon composites for enhancing electromagnetic interference (EMI) shielding properties. Featuring a CNT film with nano-scale pores and an amorphous carbon layer with micro-scale pores, the CNT/carbon composites are strategically arranged to promote the penetration of EM waves into the composite's interior and facilitate multiple reflections, thereby improving the EMI shielding performance. An impressive EMI shielding effectiveness of 61.4 dB was achieved by the CNT/carbon composites, marking a significant improvement over the 36.5 dB measured for the pristine CNT film. Owing to the micro pores in the amorphous carbon layer, a notable reduction in the reflection shielding efficiency (SER) but, concurrently, a substantial increase in the absorption shielding efficiency (SEA) compared with the pristine CNT film was realized in the composites. This study successfully validated the effectiveness of the hierarchical porous structure in enhancing the EMI shielding performance, providing a promising new strategy for the development of lightweight, flexible, and efficient EMI shielding materials.

4.
Biosens Bioelectron ; 165: 112373, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32729505

RESUMEN

Herein, size-controllable molybdenum carbide nanoparticles (Mo2C NPs) encapsulated by N, P-codoped carbon shells which simultaneously wrapping on the surface of carbon nanotube (Mo2C@NPC/CNT) is synthesized through a molecular-scale cage-confinement pyrolysis route. Such confinement achieves a good coating and protection of Mo2C and the effective control over the size of Mo2C NPs ranging from 2.5 to 10 nm facilitates a rational investigation into their electrochemical sensor behavior at nanometer scales. The optimized structure consisting of Mo2C nanoparticles with size of ~5 nm showed an outstanding electrochemical response toward dopamine (DA) and acetaminophen (AC) with detection limits (S/N = 3) of 0.008 µM for AC and 0.01 µM for DA.


Asunto(s)
Técnicas Biosensibles , Nanopartículas , Técnicas Electroquímicas , Electrodos , Molibdeno , Pirólisis
5.
ACS Appl Mater Interfaces ; 11(25): 22457-22463, 2019 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-31194506

RESUMEN

Copper sulfide has been regarded as a promising thermoelectric material with relatively high thermoelectric performance and abundant resource. Large-scale synthesis and low-cost production of high-performance thermoelectric materials are keys to widespread application of thermoelectric technology. Here, Cu2- xS particles encapsulated in a thin carbon shell are fabricated by a scalable wet chemical method (19.7 g/batch). The synthesized particles go through the crystal-phase transition from orthorhombic to tetragonal during high-temperature annealing and sintering. After the phase transition, electrical conductivity of this composite (Cu2- xS@C) increases by approximately 50% compared to that of the pure Cu2- xS sample, and can be attibuted to an increase in carrier concentration. Phonon scattering interface formation and superionic phase of Cu2- xS@C results in very low lattice thermal conductivity of 0.22 W m-1 K-1, and maximum thermoelectric figure of merit ( ZT) of 1.04 at 773 K, which is excellent for thermoelectric performance in pure-phase copper sulfide produced via chemical synthesis. This discovery sets the stage for the use of facile wet chemical synthesis methods for large-scale transition-metal chalcogenide thermoelectric material production.

6.
Curr Pharm Des ; 24(21): 2425-2431, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29766786

RESUMEN

Crystallization is a significant process employed to produce a wide variety of materials in pharmaceutical and food area. The control of crystal dimension, crystallinity, and shape is very important because they will affect the subsequent filtration, drying and grinding performance as well as the physical and chemical properties of the material. This review summarizes the special features of crystallization technology and the preparation methods of nanocrystals, and discusses analytical technology which is used to control crystal quality and performance. The crystallization technology applications in pharmaceutics and foods are also outlined. These illustrated examples further help us to gain a better understanding of the crystallization technology for pharmaceutics and foods.


Asunto(s)
Industria de Alimentos , Nanopartículas/química , Biofarmacia , Cristalización
8.
Acta Histochem ; 112(3): 233-9, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19428056

RESUMEN

It has been demonstrated that tissue factor (TF) may be involved in the tumor-derived procoagulatory status and angiogenic modulation in certain solid tumors. In the present study, we examined immunohistochemical localisation of TF in esophageal squamous cell carcinomas (ESCC) from 103 patients. TF immunopositivity was found in 91.3% of all tumor sections, while normal esophageal tissues were immunonegative. Patients were divided into a low TF immunoreactivity group (9 cases of negative and 48 cases of weak positive) and a high TF immunoreactivity group (35 cases of moderate positive and 11 cases of strong positive). TF immunoreactivity was significantly correlated to the presence of distant metastasis (P=0.0014), while it was not correlated to patient's gender, age, tumor size, depth of tumor invasion or lymph node metastasis. Survival analysis revealed that the overall survival rate in the patients that had high TF immunoreactivity was significantly poorer than those with low TF immunoreactivity (P=0.0094). Univariate analysis demonstrated that tumor size (P=0.0095), depth of tumor invasion (P=0.0050), lymph node metastasis (P=0.0045) and distant metastasis (P<0.0001) were effective predictors of prognosis in patients. However, only distant metastasis could independently predict patients' outcomes by the analysis of multivariate proportional hazards regression (P=0.0043). Furthermore, the intratumoral microvessel density (MVD), evaluated by CD34 immunolabeling, indicated that MVD was positively correlated to the TF immunoreactivity (P=0.0056). It is concluded that TF immunopositivity in ESCC tissues is strongly correlated to the intratumoral angiogenesis and to poor patient prognosis.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Metástasis Linfática/diagnóstico , Microvasos/patología , Neovascularización Patológica/patología , Tromboplastina/metabolismo , Adulto , Factores de Edad , Anciano , Antígenos CD34/metabolismo , Carcinoma de Células Escamosas/irrigación sanguínea , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/irrigación sanguínea , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patología , Femenino , Hemostáticos/metabolismo , Humanos , Metástasis Linfática/patología , Masculino , Microvasos/metabolismo , Persona de Mediana Edad , Análisis Multivariante , Neovascularización Patológica/metabolismo , Modelos de Riesgos Proporcionales , Factores Sexuales , Análisis de Supervivencia
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