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1.
Nanotechnology ; 33(27)2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35272278

RESUMO

In this study, we have investigated the improvements in the performance of an all-solid-state complementary electrochromic device (ECD) by using the proposed high pressure treatment (HPT). The Li:Ta2O5electrolyte layer was recrystallized by the HPT utilizing pressurized CO2gas (∼200 atm) and at low temperature (<60 °C), which enhanced the coloration performance of the WO3/Li:Ta2O5/NiO complementary ECD by ∼20%. The reliability and durability of the ECD were confirmed by long term transmittance retention measurements, which indicated an improvement in the coloration performance by ∼14% upon the release of the bias voltages. The ability of the devices that were fabricated with and without the HPT process to withstand high temperature environments was also verified. In addition, photoluminescence (PL) and transmittance measurements were carried out to examine the effects of the bonding between WO3and NiO. To determine the differences in lithium-ion (Li+) injection, electrical measurements were performed by utilizing varying pulse rising speeds to confirm device characteristics. The materials were characterized in terms of their composition and structure using high-resolution transmission electron microscopy along with energy-dispersive x-ray spectroscopy. Finally, a mechanistic model has been proposed to explain the improved EC characteristics based on the amorphous to crystalline transition accompanying the HPT process.

2.
Biochem J ; 430(2): 215-21, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20569199

RESUMO

PtdIns5P 4-kinases IIalpha and IIbeta are cytosolic and nuclear respectively when transfected into cells, including DT40 cells [Richardson, Wang, Clarke, Patel and Irvine (2007) Cell. Signalling 19, 1309-1314]. In the present study we have genomically tagged both type II PtdIns5P 4-kinase isoforms in DT40 cells. Immunoprecipitation of either isoform from tagged cells, followed by MS, revealed that they are associated directly with each other, probably by heterodimerization. We quantified the cellular levels of the type II PtdIns5P 4-kinase mRNAs by real-time quantitative PCR and the absolute amount of each isoform in immunoprecipitates by MS using selective reaction monitoring with 14N,13C-labelled internal standard peptides. The results suggest that the dimerization is complete and random, governed solely by the relative concentrations of the two isoforms. Whereas PtdIns5P 4-kinase IIbeta is >95% nuclear, as expected, the distribution of PtdIns4P 4-kinase IIalpha is 60% cytoplasmic (all bound to membranes) and 40% nuclear. In vitro, PtdIns5P 4-kinase IIalpha was 2000-fold more active as a PtdIns5P 4-kinase than the IIbeta isoform. Overall the results suggest a function of PtdIns5P 4-kinase IIbeta may be to target the more active IIalpha isoform into the nucleus.


Assuntos
Núcleo Celular/enzimologia , Genômica , Fosfotransferases/genética , Fosfotransferases/metabolismo , Animais , Linhagem Celular Transformada , Núcleo Celular/genética , Galinhas , Citoplasma/enzimologia , Citoplasma/genética , Dimerização , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Fosfotransferases/química , Ligação Proteica , Transporte Proteico
3.
Cell Signal ; 19(6): 1309-14, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17303380

RESUMO

Previous studies from acutely transfected HeLa cells have identified an acidic alpha-helix in the Type IIbeta PtdIns5P 4-kinase (PIPkin IIbeta) as a putative novel nuclear localisation sequence (Ciruela et al. Biochem. J. 364, 587-591 2000). However, some heterogeneity in cellular localisation was always observed, and other published aspects of PIPkin IIbeta physiology are more consistent with an extra-nuclear function. As a means of resolving whether the endogenous PIPkin IIbeta is nuclear, we have used the high homologous recombination frequency of DT40 cells to knock an epitope tag (Mosedale et al., Nat Struct Biol. 12, 763-771 2005) into one of the alleles of the DT40 PIPkin IIbeta gene. We show that PIPkin IIbeta is expressed as a tagged protein, is active as revealed by immunoprecipitation and enzyme assay, and that cellular fractionation reveals that it is indeed nuclear. Genomic tagging of endogenous proteins in DT40 cells is a technique that offers unique advantages in studying endogenous signalling proteins.


Assuntos
Núcleo Celular/enzimologia , Genoma , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Sequência de Aminoácidos , Animais , Galinhas , Humanos , Dados de Sequência Molecular , Fosfotransferases (Aceptor do Grupo Álcool)/química , Transporte Proteico , Frações Subcelulares/enzimologia , Transfecção
4.
J Asian Nat Prod Res ; 5(1): 25-30, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12608635

RESUMO

Two new glycosyl flavonoids including a glycosyl aurone, together with six known flavonoids were isolated from the roots and rhizomes of Asarum longerhizomatosum. The structures of the two new compounds were elucidated as 4,6,4'-trihydroxy-aurone-4,6-di-O-beta-D-glucopyranoside (7, caulesauroneside) and naringenin-7,4'-di-O-beta-D-glucopyranoside (8, caulesnarinside). The six known flavonoids were identified as naringenin (1), naringenin-5-O-beta-D-glucopyranoside (2), naringenin-7-O-beta-D-glucopyranoside (3), chalcononaringenin-2'-O-beta-D-glucopyranoside (4), naringenin-5,7-di-O-beta-D-glucopyranoside (5), chalcononaringenin-2',4'-di-O-beta-D-glucopyranoside (6), respectively. This is the first report of the isolation of aurones in the family Aristolochiaceae.


Assuntos
Asarum , Flavonoides/química , Fitoterapia , Extratos Vegetais/química , Glicosilação , Humanos , Espectroscopia de Ressonância Magnética , Raízes de Plantas , Relação Estrutura-Atividade
5.
Zhongguo Zhong Yao Za Zhi ; 28(6): 533-5, 2003 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-15015334

RESUMO

OBJECTIVE: To analyze and identify fatty acids in the seeds of Sterculia lychnophora. METHOD: The compositions was isolated and determined by GC-MS technique, and area normalization method was used to make quantitative analyze of the content of compositions. RESULTS: 21 Fatty acids and 5 other compositions were isolated and determined. CONCLUSION: The major fatty acids are 9,12(Z,Z)-octadecadienoic acid(37.96%), hexadecanoic acid(24.77%), 9-(Z)-octadecenoic acid(19.77%) and octadecanoic acid(5.01%).


Assuntos
Ácidos Graxos não Esterificados/isolamento & purificação , Plantas Medicinais/química , Sterculia/química , Ácidos Graxos não Esterificados/química , Ácidos Graxos Insaturados/análise , Cromatografia Gasosa-Espectrometria de Massas , Ácido Palmítico/análise , Sementes/química
6.
Zhongguo Zhong Yao Za Zhi ; 27(4): 277-9, 2002 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-12774372

RESUMO

OBJECTIVE: To study the chemical constituents from the seed of Trigonella foenum-graecum. METHOD: The compounds were isolated with silica gel chromatography and their structures were identified by physical, chemical properties and spectral analysis. RESULT: Seven compounds were isolated and identified as N,N'-dicarbazyl, glycerol monopalmitate, stearic acid, beta-sitosteryl glucopyranoside, ethyl-alpha-D-glucopyranoside, D-3-O-methyl-chiroinsitol and sucrose. CONCLUSION: All the compounds were obtained from this plant for the first time and N,N'-dicarbazyl is a new natural product.


Assuntos
Carbazóis/isolamento & purificação , Plantas Medicinais/química , Trigonella/química , Carbazóis/química , Sementes/química , Ácidos Esteáricos/química , Ácidos Esteáricos/isolamento & purificação
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