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1.
Toxicol Mech Methods ; : 1-16, 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33467949

RESUMO

Smokeless tobacco products provide an alternative to cigarettes; however, smokeless tobacco is carcinogenic and harmful to human health. This study evaluated the toxicological effects of snus extracts and cigarette smoke total particulate matter (TPM) on human umbilical vein endothelial cells (HUVECs). Treated cells were examined for cell viability, reactive oxygen species (ROS), apoptosis, and inflammatory cytokines. Moreover, we explored the mechanism of programmed cell death induced by snus. The results showed that snus extracts significantly inhibited cell viability in a dose-dependent manner. ROS was significantly increased in treatment groups, and anti-oxidant treatment could not prevent snus extract-induced cell death. Snus extracts induced apoptosis, DNA damage, activation and cleavage of caspase-3 and caspase-8, pathway-related gene change, and interleukin (IL)-6 and IL-8 release in HUVECs. Snus extracts exposure may induce cytotoxicity, ROS generation, inflammatory cytokines release, and apoptosis or DNA damage through intrinsic and extrinsic pathways in HUVECs.

2.
Int J Biol Macromol ; 138: 511-518, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31336119

RESUMO

Citrus grandis 'Tomentosa' (CGT) which is a region-famous medicinal and edible plant contains plentiful bioactive polysaccharides, however, its chemical structures and specific bioactivities still need to be further explored. In the present study, an acidic polysaccharide (CGTP-AP) was extracted and purified from the pulps of CGT. The structure elucidation and anti-cancer activity of CGTP-AP were investigated. Structure characterization indicated that CGTP-AP was a homogeneous heteropolysaccharide composed of arabinose, galactose and galacturonic acid in a molar ratio of 2.45:1:2.77, with an average molecular weight of 2721.68 kDa. Partial acid hydrolysis, methylation and NMR spectrometry revealed that the backbone of CGTP-AP mainly composed of (1 → 4)-α-D-galacturonan, while the branch principally consisted of (1 → 5)-α-L-Araf. In addition, CGTP-AP exhibited effective anti-proliferation against colon cancer cells LOVO and SW620 cells in dose- and time-dependent manners, with IC50 values of 5.55, 4.35 and 3.52 mg mL-1 after 24, 48 and 72 h, and 5.33, 3.63 and 2.97 mg mL-1 after 24, 48 and 72 h, respectively. This study indicated that CGTP-AP might be utilized as a promising food supplement for the patients of colon disorders.


Assuntos
Citrus/química , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polissacarídeos/química , Polissacarídeos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Hidrólise , Espectroscopia de Ressonância Magnética , Metilação , Extratos Vegetais/isolamento & purificação , Polissacarídeos/isolamento & purificação , Relação Estrutura-Atividade
3.
Chem Commun (Camb) ; 51(17): 3541-4, 2015 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-25644218

RESUMO

Molecularly imprinted polymers (MIPs) were applied for selective enrichment of proteins in MALDI-TOF MS analysis for the first time. MIPs were achieved simply via immobilization of template lysozyme (Lyz) on core-shell magnetic nanoparticles and self-polymerization of dopamine (DA).


Assuntos
Impressão Molecular , Muramidase/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Biopolímeros/química , Dopamina/química , Nanopartículas de Magnetita/química , Muramidase/metabolismo , Tamanho da Partícula , Polimerização , Propriedades de Superfície
4.
Talanta ; 134: 425-434, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25618689

RESUMO

Vinyl-functionalized silica spheres (VFSS) were synthesized through the one-step method. The effects of reactant ratio, temperature, reaction time and ammonium hydroxide dripping speed were investigated. The diameter of the spheres reached sub-2 µm magnitude by controlling the reaction conditions, which is suitable for high performance liquid chromatography (HPLC) packing material. The vinyl groups in the silica spheres were further successfully modified by octadecyl (C18) groups through a "thiol-ene" click reaction. Raw VFSS and C18modified VFSS (C-VFSS) were used as HPLC stationary phases to separate benzene homologs (benzene, toluene, and meta-xylene) and nonpolar compounds with different ring contents (benzene, phenantherene and fluoranthene). Both VFSS and C-VFSS exhibited hydrophobic retention behavior. Additionally, vinyl groups in the silica spheres may offer a π-π electron-donor-acceptor (EDA) retention mechanism for chromatographic separation.

5.
Yan Ke Xue Bao ; 25(1): 38-40, 2010 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-21166039

RESUMO

PURPOSE: To observe the changes of macular thickness in patients with sleep apnea syndrome (SAS) before and after sleep. METHODS: Thirty-two patients (63 eyes) diagnosed as SAS from August 2003 to January 2007 were enrolled. Macular thickness were measured using optical coherence tomography (OCT) at 11:00 to 12:00 evening (before sleep)and 20 to 30 minute after sleep, respectively. RESULTS: The mean macular thickness was (123.00+/-19.98)um and (134.25+/-19.92)um before and after sleep, respectively. The mean difference was (11.25+/-9.04)um before and after sleep(t=9.878,p<0.05),95%CI(8.98,13.53)um. CONCLUSIONS: The macular thickness of SAS is increased in SAS patients, which may due to anoxia of SAS.


Assuntos
Edema Macular , Tomografia de Coerência Óptica , Olho , Humanos , Síndromes da Apneia do Sono
6.
Chem Commun (Camb) ; (12): 1470-2, 2008 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-18338059

RESUMO

A WO3/CeO2-ZrO2 catalyst system was discovered for selective catalytic reduction of NOx with NH3; the catalyst (10 wt% WO3 loading) showed nearly 100% NOx conversion in a temperature range of 200-500 degrees C, at a space velocity of 90 000 h(-1) in a simulated diesel exhaust containing 550 ppm NOx (NO : NO2 feed ratio at 1.0), 10 vol% H2O and 10 vol% CO2; the catalyst also exhibited high temperature stability.

7.
Huan Jing Ke Xue ; 29(11): 3114-8, 2008 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-19186812

RESUMO

The nucleation of flocculent sludge as seed in a mesophilic Internal Circulation Anaerobic reactor was investigated with a quantitative method proposed by us in this paper. In the 85th days, the average sludge diameter increased from 47.8 microm to 96.1 microm, which indicated that the nucleation was completed. During this process, the average sludge diameter had a significant linear correlation with the time with coefficient of 0.9893, the increase rate of average sludge diameter was 0.58 microm/d. Nucleus ratio of sludge increased from 7.6% on the 1st day to 36.1% on the 85th day. The increase rate of the nucleus ratio fluctuated in a wide range, experienced 'fast-slow-fast' three stages. During the experiment, the concentration of extra cellular polymers (ECPs) of the sludge was significantly positively correlated with the increase rate of the nucleus ratio, which indicated that ECPs could affect nucleation rate. During nucleation, the bio-activity of the sludge increased, but the improvement of settlement ability was not significant. The above-mentioned quantitative method and results would be useful to understand the sludge granulation mechanism on the level of reactor.


Assuntos
Reatores Biológicos , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Anaerobiose , Floculação , Tamanho da Partícula , Polímeros/análise
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(7): 1064-7, 2005 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16241056

RESUMO

Polystyrene/poly (methyl methacrylate) (PS/PMMA) was studied after the thin films were prepared on glass substrate by spin-coating from THF. Raman spectroscopy combined with microscopy was used to obtain information on the morphology and structure of the thin films. From the relative intensities of the peaks around 1 604 and 1 585 cm(-1) due to stretching of benzene rings, and 1 728 cm(-1) due to stretching of C=O for PS and PMMA respectively, the authors could define the composition of the domains in the sea-island-like phase-separated structure in the microscopic image. Furthermore, the structure evolution was followed by Raman spectroscopy during the in-situ annealing of PS/PMMA (30/70) blend thin films at 210 degrees C. And the effect of SERS on the PS thin films was also discussed.


Assuntos
Polimetil Metacrilato/química , Poliestirenos/química , Análise Espectral Raman/métodos , Microscopia/métodos , Estrutura Molecular , Análise Espectral Raman/instrumentação , Propriedades de Superfície
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