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1.
Biosens Bioelectron ; 211: 114339, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35588636

RESUMO

By D-arginine and L-arginine chiral peptides induced spin selectivity and Au NPs enhanced spin polarization, chiral peptides purification has been effectively simplified and the purification performance has raised from a mixture system. The angular momentums of light are operated by the polarizer and wave plates. Au NPs decorated ZnO nanorods electrodes are utilized to modulate the polarization of spintronic. Seed growth methods are for synthesizing spherical Au NPs. UV light reduction methods are for urchin-liked Au NPs. Au NPs are decorated on ZnO nanorods electrodes for rising photon to electron conversion efficiency and enhancing spin polarization rates by surface plasmon effect. From our results, photon to the electron conversion efficiency of ZnO nanorods electrodes has effectively enhanced by urchin-liked Au NPs decorating. Ultrahigh localized plasmon conversion efficiency as high as 60% was also obtained. Besides, density functional theory (DFT) calculations simulated the force on spintronic. Since the D-arginine and L-arginine are on Au substrate, DFT results demonstrate different angular momentum and spin polarization coupling. Along with urchin-liked Au NPs rising chiral induced spin polarization by surface plasmon resonance, the sensitivity of chiral arginine has been raised around 5000% from bare ZnO nanorods electrodes. The purification and separation time of a specific chiral arginine only needs 5 min.


Assuntos
Técnicas Biossensoriais , Óxido de Zinco , Arginina , Ouro , Peptídeos
2.
Addiction ; 116(5): 1172-1185, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32918512

RESUMO

BACKGROUND AND AIMS: Three to 10 minutes of smoking cessation advice by physicians is effective to increase quit rates, but is not routinely practised. We examined the effectiveness of physicians' very brief (approximately 30 sec) smoking cessation intervention on quit rates among Chinese outpatient smokers. DESIGN: A pragmatic, open-label, individually randomized controlled trial. SETTING: Seventy-two medical outpatient departments of hospitals and/or community health centers in Guangdong, China. PARTICIPANTS: Chinese adults who were daily cigarette smokers (n = 13 671, 99% males) were invited by their physician to participate during outpatient consultation. Smokers who were receiving smoking cessation treatment or were judged to need specialist treatment for cessation were excluded. INTERVENTIONS: The intervention group (n = 7015) received a 30-sec intervention including physician's very brief advice, a leaflet with graphic warnings and a card with contact information of available cessation services. The control group (n = 6656) received a very brief intervention on consuming vegetables and fruit. A total of 3466 participants in the intervention group were further randomized to receive a brief booster advice from trained study personnel via telephone 1 month following their doctor visit. MEASUREMENTS: The primary outcome was self-reported 7-day point prevalence abstinence (PPA) in the intervention and control groups at the 12-month follow-up. Secondary outcomes included self-reported 30-day abstinence and biochemically validated abstinence at 12-month follow-up. FINDINGS: By intention-to-treat, the intervention (versus control) group had greater self-reported 7-day abstinence [9.1 versus 7.8%, odds ratio (OR) = 1.14, 95% confidence interval (CI) = 1.03-1.26, P = 0.008] and 30-day abstinence (8.0 versus 6.9%, OR = 1.14, 95% CI = 1.03-1.27, P = 0.01) at 12-month follow-up. The effect size increased when only participants who received the intervention from compliant physicians were included (7-day PPA, OR = 1.42, 95% CI = 1.11-1.74). The group difference in biochemically validated abstinence was small (0.8 versus 0.8%, OR = 1.00, 95% CI = 0.71-1.42, P = 0.99). CONCLUSION: A 30-sec smoking cessation intervention increased self-reported abstinence among mainly male smokers in China at 12-month follow-up (risk difference = 1.3%), and should be feasible to provide in most settings and delivered by all health-care professionals.


Assuntos
Médicos , Abandono do Hábito de Fumar , Adulto , China , Feminino , Humanos , Masculino , Fumantes , Telefone
3.
J Proteomics ; 177: 40-47, 2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29438852

RESUMO

Polygoni Multiflori Radix (PMR) has been commonly used as a tonic in China for centuries. However, PMR-associated hepatotoxicity is becoming a safety issue. Cholestasis often occurs in PMR-induced hepatotoxicity in clinical medicine, but the exact mechanism is not completely understood. An RNA-Seq method was employed, in the present study, to explore the molecular mechanism of cholestatic liver injury induced by PMR, characterized by the hepatic transcriptional response in rats exposed to 1 and 20 g/kg PMR for 90 days. Pathological changes seen in rat livers exposed to PMR included increased bile ducts in portal areas and biliary epithelial cell hyperplasia, which were accompanied by the elevation of serum biochemistries. Dose-dependent increases in the expression of 14 transcripts encoding enzymes involved in the cholesterol biosynthetic pathway were identified. Furthermore, cholesterol 7-alpha hydroxylase (Cyp7a1), a rate-limiting enzyme in the synthesis of bile acids (BAs) from cholesterol, was found to be upregulated by PMR treatment. Protein analysis by western blot suggested that expression of 3-hydroxy-3-methylglutaryl CoA reductase (Hmgcr) and Cyp7a1 were increased in a dose-dependent manner. Collectively, the present study demonstrates that PMR upregulates key enzymes for biosynthesis of cholesterol and BA, which poses the risk of cholestatic liver injury. SIGNIFICANCE: To the best of our knowledge, this is the first transcriptome analysis to highlight the main molecular changes occurring in rats chronic exposed to PMR. We have identified 39 specific differentially expressed genes (DEGs) that were present in various comparisons. A total of 14 of these altered gene transcripts were associated with cholesterol biosynthesis. Another factor of great importance in our opinion seemed to be the enhancement of bile acid (BA) biosynthesis, which were closely linked to cholesterol biosynthesis or metabolism. Our findings suggested that the disturbance on balance of BA formation and elimination might lead to a BA overload in hepatocytes, thereby resulting in liver injury.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Colestase/induzido quimicamente , Perfilação da Expressão Gênica/métodos , Polygonum/toxicidade , Animais , Ácidos e Sais Biliares/biossíntese , Vias Biossintéticas/genética , Colesterol/biossíntese , Fígado/enzimologia , Fígado/metabolismo , Fígado/patologia , Ratos , Regulação para Cima
4.
ACS Appl Mater Interfaces ; 10(5): 5007-5013, 2018 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-29337527

RESUMO

A firefly-like chemiluminescence reaction was utilized in a ZrO2 nanoparticle matrix of water splitting cells, where the chlorophyll of Lantana camara was used as the major photosensitizer to excite electrons to the conduction band of ZrO2. The fluorescence resonance energy transfer (FRET) was induced by rubrene, a firefly-like chemiluminescence molecule, and Lantana camara chlorophyll combined with 9,10-diphenylanthracene. The ZrO2 nanoparticle film coated by the chlorophyll of Lantana camara and 9,10-diphenylanthracene under chemiluminescence irradiation in 1 M KHCO3 water solution demonstrated the highest photocurrent density (88.1 A/m2) and the highest water splitting efficiency (12.77%).


Assuntos
Água/química , Transferência Ressonante de Energia de Fluorescência
5.
Vascul Pharmacol ; 55(5-6): 135-42, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21777697

RESUMO

Nonsteroidal anti-inflammatory drugs (NSAIDs) are previously found to possess prostaglandin and leukotriene-independent anti-inflammatory effect. The aim of the present study was to investigate the prostaglandin and leukotriene-independent anti-inflammatory effect of an imidazolone COX/5-LOX inhibitor ZLJ-6 and the underlying mechanism. Pretreatment human umbilical vein endothelial cells (HUVECs) with ZLJ-6 (3, 10 and 30 µM) concentration-dependently decreased TNF-α-induced monocyte-endothelial interactions in both static and dynamic conditions whereas no effect was found after pretreatment with the COX-2 inhibitor celecoxib (30 µM), 5-LOX inhibitor zileuton (30 µM) and the combination of them. ZLJ-6 also attenuated expression of E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cytoadhesion molecule-1 (VCAM-1) on TNF-α-induced HUVECs. A further analysis indicated that ZLJ-6 attenuated TNF-α-induced nuclear translocation of NF-κB, IκB phosphorylation, IκB kinase ß (IKKß) activity, and subsequent NF-κB-DNA complex formation, suggesting that NF-κB pathway was involved in TNF-α-induced inflammation. However, ZLJ-6 did not affect TNF-α-induced extracellular signal-regulated kinases (ERK1/2), c-Jun N-terminal kinases (JNK) and p38 phosphorylation. Taken together, our results indicated that ZLJ-6 potently inhibited TNF-α-induced monocyte-endothelial interactions and adhesion molecule (E-selectin, ICAM-1 and VCAM-1) expression and these effects were mediated by NF-κB signaling pathway rather than its primary pharmacological target COX-2 or 5-LOX.


Assuntos
Moléculas de Adesão Celular/biossíntese , Membrana Celular/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase/farmacologia , Endotélio Vascular/efeitos dos fármacos , Imidazóis/farmacologia , Inibidores de Lipoxigenase/farmacologia , Monócitos/efeitos dos fármacos , Sulfonas/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Araquidonato 5-Lipoxigenase/química , Araquidonato 5-Lipoxigenase/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Membrana Celular/metabolismo , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Células Cultivadas , Selectina E/biossíntese , Selectina E/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/imunologia , Endotélio Vascular/metabolismo , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/imunologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/biossíntese , Molécula 1 de Adesão Intercelular/metabolismo , Monócitos/imunologia , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Transporte Proteico/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Molécula 1 de Adesão de Célula Vascular/biossíntese , Molécula 1 de Adesão de Célula Vascular/metabolismo
6.
Chem Biodivers ; 6(4): 466-74, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19353543

RESUMO

In search of more potent anticancer agents, 15 nitric oxide (NO)-donating thalidomide analogues, 6a, 6b, 8a-8e, and 13a-13h, were designed and synthesized. Cytotoxicity of these compounds was evaluated in vitro against three human tumor cell lines (HepG2, A549, and PC-3). The results indicated that 13a-13d exhibited notable anticancer activities comparable to or stronger than that of 5-fluorouracil (5-FU). Structure-activity relationships were also discussed, based on the experimental data obtained. Generally, the cytotoxic activity of target compounds is closely related to the type of NO donors, and the length of the spacers connecting to NO donors also appears important for the bioactivities.


Assuntos
Antineoplásicos/síntese química , Óxido Nítrico/química , Talidomida/análogos & derivados , Antineoplásicos/toxicidade , Linhagem Celular Tumoral , Fluoruracila/toxicidade , Humanos , Talidomida/toxicidade
7.
Chem Biodivers ; 5(9): 1743-52, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18816527

RESUMO

In search of novel anticancer agents, two series of dimethyl [1,1'-biphenyl]-2,2'-dicarboxylate derivatives, 8a-8k and 9a-9k, containing both methylenedioxy and 1,3,4-thiadiazole moieties were designed and synthesized. Cytotoxicity of these compounds was evaluated in vitro against five human tumor cell lines, i.e., HepG2, KB, A549, K562, and MCF-7. The results indicated that 8h, 8j, 8k, 9d, 9g, 9h, 9j, and 9k showed notable anticancer activities comparable to or stronger than that of 5-fluorouracil, a canonical anticancer drug. Structure-activity relationships were also discussed based on the experimental data obtained.


Assuntos
Compostos de Bifenilo/síntese química , Compostos de Bifenilo/toxicidade , Tiadiazóis/química , Compostos de Bifenilo/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Metilação , Estrutura Molecular , Relação Estrutura-Atividade
8.
J Phys Condens Matter ; 18(46): 10457-67, 2006 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-21690930

RESUMO

Pulsed-laser deposited (Pb,Sr)TiO(3) (PSrT) films on Pt/SiO(2)/Si substrate at various ambient oxygen pressures (P(O(2))) are investigated in this work. Films deposited at P(O(2)) below 100 mTorr exhibit the (100) preferred orientation and a tetragonal structure with larger tetragonality. In addition, films deposited at 80 mTorr exhibit the most apparent ferroelectric properties in contrast to those deposited at 200 mTorr. Moreover, films deposited at higher P(O(2)) also exhibit longer lifetimes and higher breakdown fields due to their smaller leakage current density, in terms of the reduction of defects, compensation of oxygen vacancies (OVs), an improved interface and small cluster sizes. An energy band model reveals that fatigue properties of PSrT films are dominated by interfacial states at low P(O(2)) and by deep trapping states at high P(O(2)), which could be ascribed to OVs located at the interfaces and inside films, respectively.

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