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1.
Adv Mater ; 36(14): e2309183, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38160321

RESUMO

Development of miniaturized thin-film lithium-ion batteries (TF-LIBs) using vacuum deposition techniques is crucial for low-scale applications, but addressing low energy density remains a challenge. In this work, structures analogous to SiOx-based thin-film electrodes are designed with close resemblance to traditional LIB slurry formulations including active material, conductive agent, and binder. The thin-film is produced using mid-frequency sputtering with a single hybrid target consisting of SiOx nanoparticles, carbon nanotubes, and polytetrafluoroethylene. The thin-film SiOx/PPFC (plasma-polymerized fluorocarbon) involves a combination of SiOx and conductive carbon within the PPFC matrix. This results in enhanced electronic conductivity and superior elasticity and hardness in comparison to a conventional pure SiOx-based thin-film. The electrochemical performance of the half-cell consisting of thin-film SiOx/PPFC demonstrates remarkable cycling stability, with a capacity retention of 74.8% up to the 1000th cycle at 0.5 C. In addition, a full cell using the LiNi0.6Co0.2Mn0.2O2 thin-film as the cathode material exhibits an exceptional initial capacity of ≈120 mAh g-1 at 0.1 C and cycle performance, marked by a capacity retention of 90.8% from the first cycle to the 500th cycle at a 1 C rate. This work will be a stepping stone for the AM/CB/B composite electrodes in TF-LIBs.

2.
Nanoscale ; 13(28): 12260-12270, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34241610

RESUMO

This study proposes a plasmonic resonance-tunable nanocomposite thin film, which applies to a color filter, heat mirror, semi-transparent color electrode, and electromagnetic shield, given that the size and structure of nanoclusters can be controlled by a sputtering power density. The structural and functional properties of silver/plasma-polymer-fluorocarbon (Ag/PPFC) nanocomposite thin films, which were sputtered by ternary composite targets, were investigated with various compositions and sputtering power densities. The growth of Ag nanoclusters of the thin film was suppressed as the sputtering power density increased due to the rich functional group of -CFx- fluorine. As a result, a continuous color change from blue to yellow could be expressed on films given the precise control of the surface plasmonic resonance phenomenon. Grazing-incidence small-angle scattering (GISAXS) analysis indicated that the sputtering power density had a significant effect on the size, distribution, and orientation of the Ag nanoclusters in the thin film. For low sputtering power densities, Ag nanoclusters were forming aggregations along the out-of-plane direction, but as the sputtering power density increased, the nanoclusters showed random distribution instead of large aggregates. We also demonstrated applications of Ag/PPFC nanocomposite thin films to a color filter, heat mirror, semi-transparent electrode, and electromagnetic shield. In addition, the fabrication of a large-area film (400 × 700 mm2) showed that the approach applies highly to industries.

3.
ACS Appl Mater Interfaces ; 13(8): 10301-10312, 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33591732

RESUMO

Polymer thin films containing fluorine are attracting much attention in various high-tech industries owing to their transparency, flexibility, and excellent water repellency. However, the generation of static electricity due to high electrical resistance limits their application. In this study, highly transparent and flexible Cu-plasma-polymerized fluorocarbon (PPFC) nanocomposite thin films that exhibit hydrophobicity and antistatic properties are proposed. These films, obtained using the mid-range frequency sputtering, exhibited a light transmittance of 84.2%, a water contact angle of 94.6°, and a sheet resistance of 1.2 × 1012 Ω/□. Transmission electron microscopy and small angle X-ray scattering confirmed that Cu nanoparticles with an average size of 4-5 nm were distributed uniformly in the PPFC matrix. In repeated fatigue bending tests, the Cu-PPFC nanocomposite thin films exhibited excellent mechanical robustness and flexibility. Antiviral properties of the Cu-PPFC nanocomposite thin films were evaluated against influenza A virus, and the number decreased by 96.9% after 30 min. Carbon nanotube-Cu-polytetrafluoroethylene composite targets are advantageous for large-area coating and mass production because they can be applied in large-area sputtering and roll-to-roll processes. The transparency, charging characteristics, and water repellency can be easily controlled in Cu-PPFC nanocomposite thin films by controlling the sputtering power density according to the required product. Therefore, these films can be applied in various industries such as flexible displays, medical, automobiles, functional textiles, and aerospace.


Assuntos
Substâncias Antieletricidade Estática/farmacologia , Antivirais/farmacologia , Cobre/farmacologia , Polímeros de Fluorcarboneto/farmacologia , Membranas Artificiais , Nanocompostos/química , Substâncias Antieletricidade Estática/química , Antivirais/química , Cobre/química , Polímeros de Fluorcarboneto/química , Interações Hidrofóbicas e Hidrofílicas , Vírus da Influenza A/efeitos dos fármacos , Nanotubos de Carbono/química , Gases em Plasma/química , Maleabilidade , Polimerização , Água/química
4.
Polymers (Basel) ; 12(5)2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32370004

RESUMO

Herein, an antireflection and superhydrophobic film was obtained by uniformly forming nanostructures on the surface of polyethylene terephthalate (PET) substrate using oxygen plasma without a pattern mask and coating plasma-polymer-fluorocarbon (PPFC) on the nanostructured surface by mid-range frequency sputtering. PPFC/nanostructured-PET showed a reflectance of 4.2%, which is 56% lower than that of the PET film. Haze was also improved. Nanostructured-PET exhibited a superhydrophilic surface due to plasma deformation and a superhydrophobic surface could be realized by coating PPFC on the nanostructured surface. The PPFC coating prevented the aging of polymer film nanostructures and showed excellent durability in a high-temperature and high-humidity environment. It exhibited excellent flexibility to maintain the superhydrophobic surface, even at a mechanical bending radius of 1 mm, and could retain its properties even after repeated bending for 10,000 times.

6.
J Racial Ethn Health Disparities ; 6(4): 752-773, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30859514

RESUMO

Decades of research have established that racial ethnic minority, low-income, and/or non-English speaking children with autism spectrum disorder (ASD) are diagnosed later than white children, and their families experience greater difficulty accessing services in the USA. Delayed access to timely diagnosis and early intervention may impact child outcomes and family quality of life. Despite their cognition of these disparities and their significant impact on the lives of those affected, explanations for the barriers experienced by underserved families are elusive, likely due to the complex interaction between structural and family factors. This study used qualitative methods to gather family and provider perspectives of perceived barriers and facilitators to obtaining an ASD diagnosis and accessing ASD-related services for underserved families. Themes from focus groups and interviews with families from three cultural groups (black, Hispanic/Latino, and Korean) and three primary languages (English, Korean, and Spanish) highlight specific barriers related to family, community, and systemic challenges as well as facilitators to accessing care for these populations. Family experiences are expanded upon with viewpoints from the providers who work with them. Recommendations are made for reducing disparities in the existing ASD service system including increasing professional, family, and community education; increasing culturally responsive care; improving provider-family partnerships; and addressing practical challenges to service access.


Assuntos
Transtorno do Espectro Autista/etnologia , Cuidadores/psicologia , Etnicidade/estatística & dados numéricos , Acessibilidade aos Serviços de Saúde/organização & administração , Disparidades em Assistência à Saúde/etnologia , Adulto , Idoso , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/terapia , Criança , Pré-Escolar , Assistência à Saúde Culturalmente Competente/organização & administração , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Grupos Minoritários/estatística & dados numéricos , Pobreza , Pesquisa Qualitativa , Qualidade de Vida , Fatores Socioeconômicos
7.
Horm Res Paediatr ; 83(4): 242-51, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25765181

RESUMO

AIMS: To date, 13 genes causing maturity-onset diabetes of the young (MODY) have been identified. However, there is a big discrepancy in the genetic locus between Asian and Caucasian patients with MODY. Thus, we conducted whole-exome sequencing in Korean MODY families to identify causative gene variants. METHODS: Six MODY probands and their family members were included. Variants in the dbSNP135 and TIARA databases for Koreans and the variants with minor allele frequencies >0.5% of the 1000 Genomes database were excluded. We selected only the functional variants (gain of stop codon, frameshifts and nonsynonymous single-nucleotide variants) and conducted a case-control comparison in the family members. The selected variants were scanned for the previously introduced gene set implicated in glucose metabolism. RESULTS: Three variants c.620C>T:p.Thr207Ile in PTPRD, c.559C>G:p.Gln187Glu in SYT9, and c.1526T>G:p.Val509Gly in WFS1 were respectively identified in 3 families. We could not find any disease-causative alleles of known MODY 1-13 genes. Based on the predictive program, Thr207Ile in PTPRD was considered pathogenic. CONCLUSIONS: Whole-exome sequencing is a valuable method for the genetic diagnosis of MODY. Further evaluation is necessary about the role of PTPRD, SYT9 and WFS1 in normal insulin release from pancreatic beta cells.


Assuntos
Alelos , Diabetes Mellitus Tipo 2/genética , Exoma , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Povo Asiático/genética , Estudos de Casos e Controles , Criança , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Linhagem , República da Coreia
8.
Korean J Pediatr ; 56(7): 304-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23908671

RESUMO

Polyclonal gammopathy represents the diffuse activation of B cells and is usually related to inflammation or immune-related diseases. However, the mechanisms leading to polyclonal gammopathy are essentially speculative. Generally, infectious, inflammatory, or various other reactive processes may be indicated by the presence of a broad-based peak or band in the gamma region on serum protein electrophoresis results. A 15-year-old girl, who had been receiving peritoneal dialysis, presented with polyclonal gammopathy and massive gross hematuria. Renal artery embolization was performed, after which the continuous bleeding subsided and albumin-globulin dissociation resolved. This is a rare case of polyclonal gammopathy related to renal bleeding.

9.
Biochem Biophys Res Commun ; 416(3-4): 277-82, 2011 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-22093820

RESUMO

Kurtoxin, a 63-amino acid peptide stabilized by four disulfide bonds, is the first reported peptide inhibitor of T-type voltage-gated calcium channels. Although T-type calcium channels have been implicated in a number of disease states, including epilepsy, chronic pain, hypertension and cancer, the lack of selective inhibitors has slowed progress in understanding their precise roles. Kurtoxin is a potentially valuable tool with which to study T-type calcium channels. However, because of the limited availability of the native protein, little is known about the structure and molecular mechanism of kurtoxin. Here we report the expression of kurtoxin in Escherichia coli and the structural and functional characterization of the recombinant protein. The disulfide bond pairings and secondary structure of recombinant kurtoxin were characterized through enzymatic cleavage, mass analysis and CD spectroscopy. Recombinant kurtoxin almost completely inhibited the T-type calcium channel in a manner identical to the native toxin. The availability of recombinant kurtoxin that is identical to the native toxin should help in the study of T-type calcium channels and enable development of new strategies for producing even more-selective T-type calcium channel inhibitors and for investigating the molecular basis of the toxin-channel interactions.


Assuntos
Canais de Cálcio Tipo T/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia , Venenos de Escorpião/química , Venenos de Escorpião/farmacologia , Sequência de Aminoácidos , Cisteína/química , Escherichia coli/genética , Dados de Sequência Molecular , Oxirredução , Conformação Proteica , Dobramento de Proteína , Estrutura Secundária de Proteína , Proteínas Recombinantes/genética , Venenos de Escorpião/genética
10.
Biol Pharm Bull ; 29(7): 1408-13, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16819179

RESUMO

Articular cartilage is a potential target for drugs designed to inhibit the activity of matrix metalloproteinases (MMPs) to stop or slow the destruction of proteoglycan and collagen in the cartilage extracellular matrix. The purpose of this study was to investigate the effects of Betula platyphylla var. japonica on inhibiting the release of glycosaminoglycan (GAG), the degradation of collagen, and MMP expression and activity in rabbit articular cartilage explants. Interleukin-1alpha (IL-1alpha) rapidly induced GAG, but collagen was much less readily released from cartilage explants. Betula platyphylla var. japonica significantly inhibited GAG and collagen release in a concentration-dependent manner. Betula platyphylla var. japonica dose-dependently inhibited MMP-3 and MMP-13 expression and activities from IL-1alpha-treated cartilage explant culture when tested at concentrations ranging from 0.02 to 0.2 mg/ml. Betula platyphylla var. japonica had no harmful effect on chondrocyte viability or cartilage morphology in cartilage explants. Histological analysis indicated that Betula platyphylla var. japonica reduced the degradation of the cartilage matrix compared with that of IL-1alpha-treated cartilage explants. These results indicate that Betula platyphylla var. japonica inhibits the degradation of proteoglycan and collagen through the down regulation of MMP-3 and MMP-13 expression and activities without affecting the viability or morphology of IL-1alpha-stimulated rabbit articular cartilage explants.


Assuntos
Betula , Cartilagem Articular/metabolismo , Colágeno Tipo II/genética , Metaloproteinases da Matriz/genética , Extratos Vegetais/farmacologia , Proteoglicanas/metabolismo , Animais , Cartilagem Articular/citologia , Cartilagem Articular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Cinética , L-Lactato Desidrogenase/análise , Técnicas de Cultura de Órgãos , Coelhos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
J Ethnopharmacol ; 104(3): 345-50, 2006 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-16455216

RESUMO

Puerariae radix (PR) is a traditional medicine herb used for enhancing body resistance against various diseases. The aim of this study was to identify whether Puerariae radix extract induces osteogenic activity in human osteoblast-like SaOS-2 cells. Puerariae radix had no effect on the viability of osteoblastic cells, and dose-dependently increased alkaline phosphatase (ALP) activity. Puerariae radix markedly increased mRNA expression for vascular endothelial growth factor (VEGF), osteocalcin (OCN), osteopontin (OPN), and type I collagen (Col I) in SaOS-2 cells. Extracellular accumulation of proteins such as VEGF and Col I was increased in a dose-dependent manner. Also, Puerariae radix significantly induced mineralization in the culture of SaOS-2 cells. In conclusion, this study showed that Puerariae radix had no effect on viability, but enhanced ALP activity, VEGF, bone matrix proteins such as OCN, OPN, and Col I, and mineralization in SaOS-2 cells. These results propose that Puerariae radix can play an important role in osteoblastic bone formation, and may possibly lead to the development of bone-forming drugs.


Assuntos
Calcificação Fisiológica/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Osteoblastos/efeitos dos fármacos , Fosfatase Alcalina/biossíntese , Fosfatase Alcalina/genética , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Colágeno Tipo I/biossíntese , Relação Dose-Resposta a Droga , Expressão Gênica , Humanos , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteocalcina/biossíntese , Osteopontina , Pueraria , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sialoglicoproteínas/biossíntese , Fator A de Crescimento do Endotélio Vascular/biossíntese
12.
Biol Pharm Bull ; 28(12): 2248-52, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16327159

RESUMO

Angiogenesis consists of the proliferation, migration, and differentiation of endothelial cells, and angiogenic factors and matrix protein interactions modulate this process. The aim of this study was to determine the angiogenic properties of Uncaria rhynchophylla. Uncaria rhynchophylla significantly enhanced human umbilical vein endothelial cells (HUVECs) proliferation in a dose-dependent manner. Neutralization of vascular endothelial growth factor (VEGF) or basic fibroblast growth factor (bFGF) by monoclonal antibody suppressed the Uncaria rhynchophylla stimulatory effect on proliferation. In addition, Uncaria rhynchophylla significantly increased chemotactic-migration on gelatin and tubular structures on Matrigel of HUVECs in a dose-dependent manner. Interestingly, Uncaria rhynchophylla dose-dependently increased VEGF, and bFGF gene expression and protein secretion of HUVEC. The angiogenic activity of Uncaria rhynchophylla was confirmed using an in vivo Matrigel angiogenesis model, showing promotion of blood vessel formation. These results suggest that Uncaria rhynchophylla could potentially used to accelerate vascular wound healing or to promote the growth of collateral blood vessel in ischemic tissues.


Assuntos
Indutores da Angiogênese/química , Indutores da Angiogênese/farmacologia , Uncaria/química , Indutores da Angiogênese/antagonistas & inibidores , Animais , Materiais Biocompatíveis/administração & dosagem , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Colágeno/administração & dosagem , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/ultraestrutura , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fator 2 de Crescimento de Fibroblastos/farmacologia , Expressão Gênica/efeitos dos fármacos , Hemoglobinas , Humanos , Laminina/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Proteoglicanas/administração & dosagem , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Veias Umbilicais/citologia , Veias Umbilicais/efeitos dos fármacos , Veias Umbilicais/ultraestrutura , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/farmacologia
13.
Biochem Biophys Res Commun ; 320(3): 852-9, 2004 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-15240126

RESUMO

The purpose of this study was to investigate the protective effect of bio-active ceramic water on rat liver. Male Wistar rats were divided into 4 groups of 15 animals each. Groups 1 and 2 were fed bio-active ceramic water and tap water for 4 months, respectively. Groups 3 and 4 were treated with the same condition for 12 months. The changes of protein expression of these four groups were investigated using two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Eleven proteins were significantly up-regulated in bio-active ceramic water treated rat liver including aldehyde dehydrogenase I and II, albumin, fructose-1,6-bisphosphatase, and superoxide dismutase I (SOD I). The most highly expressed protein, SOD I with up-regulated enzyme activity, was confirmed by immunoblots as a major antioxidant capable of detoxifying normally generated reactive oxygen species. These data suggest that modified protein expression of the liver contributes to enhance liver function.


Assuntos
Antioxidantes/metabolismo , Enzimas/metabolismo , Fígado/metabolismo , Proteoma/metabolismo , Superóxido Dismutase/metabolismo , Purificação da Água/métodos , Água/administração & dosagem , Administração Oral , Animais , Fígado/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Superóxido Dismutase-1
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