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1.
Clin Exp Immunol ; 208(1): 25-32, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35348596

RESUMO

Asthma and allergic rhinitis (AR) are widely considered to be the most common chronic inflammatory disorders. This study was performed to investigate the clinical features, disease severity, and upper airway inflammation among patients with asthma, AR, and asthma comorbid AR. Blood and nasal lavage fluid samples were collected from patients with isolated asthma (n = 23), isolated AR (n = 22), and asthma comorbid AR (n = 22). Demographic data, symptom evaluation, and spirometry were obtained from all subjects. The levels of interleukin (IL)-4, IL-5, IL-13, IL-17, IL-25, IL-33, and S100 proteins were measured in the nasal lavage fluid. Compared with isolated asthma, patients with asthma comorbid AR showed a lower quality of life according to the asthma quality-of-life questionnaire (AQLQ) score (6.11 ± 0.47 vs. 6.45 ± 0.35, P = 0.007). Additionally, no significant difference in the levels of IL-4 (P = 0.116), IL-25 (P = 0.235), and S100A12 (P = 0.392) was observed in nasal lavage fluid among three groups. However, miniscule levels of IL-5, IL-17, IL-13, IL-33, S100A8, and S100A9 were detected in nasal lavage fluid in all three groups. Patients with asthma comorbid AR showed an increased level of systemic cytokine in plasma than that of patients with isolated AR or asthma alone. The finding from our study may help clinicians to better understand the airway inflammation among asthma patients with or without AR.


Assuntos
Asma , Rinite Alérgica , Humanos , Interleucina-17 , Interleucina-33 , Interleucina-5 , Interleucina-13 , Qualidade de Vida , Asma/metabolismo , Inflamação
2.
J Hazard Mater ; 152(3): 1301-8, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-17850958

RESUMO

The photocatalytic degradation of C.I. Direct Red 23 (4BS) in aqueous solutions under UV irradiation was investigated with SrTiO3/CeO2 composite as the catalyst. The SrTiO3/CeO2 powders had more photocatalytic activity for decolorization of 4BS than that of pure SrTiO3 powder under UV irradiation. The effects of catalytic dose, pH value, initial concentration of dye, irradiation intensity as well as scavenger KI were ascertained, and the optimum conditions for maximum degradation were determined. Under the irradiation of a 250 W mercury lamp, the best catalytic dose was 1.5 g/L and the best pH was 12.0. Light intensity exhibited a significant positive effect on the efficiency of decolorization, whereas the initial dye concentration showed a significant negative effect. Under the conditions of a catalytic dose of 1.5 g/L, pH of 12.0, initial dye concentration of 100mg/L, light intensity of 250 W, and air flow rate of 0.15 m3/h, complete decolorization, as determined by UV-visible analysis, was achieved in 60 min, corresponding to a reduction in chemical oxygen demand (COD) of 69% after a 240 min reaction. A tentative degradation pathway based on the sensitization mechanism of photocatalysis is proposed.


Assuntos
Compostos Azo/química , Cério/química , Naftalenossulfonatos/química , Óxidos/química , Estrôncio/química , Titânio/química , Raios Ultravioleta , Catálise , Concentração de Íons de Hidrogênio , Fotoquímica , Soluções , Água
3.
Ultrason Sonochem ; 14(3): 298-304, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17067839

RESUMO

Decolorization of the azo dye C.I. Reactive Black 5 (RB5) in solution by a combination of sonolysis and ozonation was investigated. The results showed that the optimum pH for the reaction was 11.0, and both lower and higher pH decreased the decolorization rate. Increasing the initial concentration of RB5 led to a decreasing decolorization rate. Under the experimental conditions, the decolorization rate increased with an increase in temperature. The decolorization of RB5 followed pseudo-first-order reaction kinetics. Based on the decolorization rate constants obtained at different temperatures within the range 287-338K and the Arrhenius equation, the apparent activation energy (E(a)) was calculated to be 11.2kJmol(-1). This indicated that the reaction has little dependence on temperature. The color decay was considerably faster than the decrease in total organic carbon (TOC), which was attributed to the ease of chromophore destruction. Hence the efficiency of decolorization was 84% compared with 4% of TOC removal after 5min reaction. Additionally, muconic acid, (2Z)-pent-2-enedioic acid and maleic acid were identified as main oxidation products by gas chromatography coupled with mass spectrometry (GC-MS) after 150min of reaction.

4.
Ultrason Sonochem ; 14(5): 568-574, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17123854

RESUMO

The degradation of p-aminophenol (PAP) in aqueous solution by sonolysis, by ozonation, and by a combination of both was investigated in laboratory-scale experiments. Operation parameters such as pH, temperature, ultrasonic energy density and ozone dose were optimized with regard to the efficiency of PAP removal. The concentration of PAP during the reaction was detected by high-pressure liquid chromatography. The concentrations of ammonium ions and nitrate ions were monitored during the degradation. Intermediate products such as 4-iminocyclohexa-2,5-dien-1-one, phenol, but-2-enedioic acid, and acetic acid were detected by gas chromatography coupled with mass spectrometry. The degradation rate of PAP was higher in the combined system than in the linear combination of separate experiments. The degradation efficiency was decreased rapidly when n-butanol was added to the combined reaction system, which showed that some radical reaction might proceed during the laboratory experiments.


Assuntos
Aminofenóis/química , Ozônio/química , Ultrassom , Poluentes Químicos da Água/química , Purificação da Água/métodos , Desenho de Equipamento , Concentração de Íons de Hidrogênio , Purificação da Água/instrumentação
5.
Chemosphere ; 66(9): 1782-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16973203

RESUMO

The decolorization and degradation of CI Direct Red 23, which is suspected to be carcinogenic, were investigated using ozonation combined with sonolysis. The results showed that the combination of ozonation and sonolysis was a highly effective way to remove color from waste water. The operational parameters, namely concentration of the dye, pH, ozone dose and ultrasonic density, were investigated during the process. The decolorization of the dye followed pseudo-first-order kinetics. Increasing the initial concentration of Direct Red 23 led to a decreasing rate constant. The optimum pH for the reaction was 8.0, and both lower and higher pH decreased the removal rate. The effect of the ozone dose on the dye decolorization was much greater than that of the sonolysis density. Intermediates such as naphthalene-2-sulfonic acid, 1-naphthol, urea and acetamide were detected by gas chromatography coupled with mass spectrometry in the absence of pH buffer, while nitrate and sulfate ions and formic, acetic and oxalic acids were detected by ion chromatography. A tentative degradation pathway was proposed without any further quantitative analyses. During the degradation, all nitrogen atoms and phenyl groups of Direct Red 23 were degraded into urea, nitrate ion, nitrogen and formic, acetic and oxalic acids, etc.


Assuntos
Compostos Azo/química , Corantes/química , Ozônio/química , Sonicação , Poluentes Químicos da Água/química , Poluição da Água/prevenção & controle , Cromatografia por Troca Iônica , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Cinética , Estrutura Molecular
6.
Chemosphere ; 69(2): 191-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17544052

RESUMO

The operational parameters and mechanism of mineralization of C.I. Reactive Yellow 84 (RY84), one of the azo dyes, in aqueous solution were investigated using sonolytic ozonation (US/O(3) oxidation). Of the pseudo-first-order degradation rate constants of TOC reduction, 9.0 x 10(-4), 7.3 x 10(-3) and 1.8 x 10(-2)min(-1) were observed with US, O3, and a combination of US and O3, respectively. These results illustrate that ozonation combined with sonolysis for removal of TOC is more efficient than ozonation alone or ultrasonic irradiation alone without considering the operating costs. With the initial pH value at 10.0, the ozone dose at 4.5 g h(-1), the energy density of ultrasound at 176 W l(-1), and the initial concentration of RY84 at 100 mg l(-1), the extent of mineralization measured as TOC loss was maximized. The variation of the concentrations of related ions (oxalate, formate, acetate, NO3(-), NO2(-), NH4(+), Cl(-), and SO4(2-)) during the reaction process was monitored. Other organic intermediates detected by GC/MS were N-methyleneaniline, phthalic acid, 4-hydroxyphthalic acid, isocyanatobenzene, aniline, 4-iminocyclohexa-2,5-dien-1-one, butene diacid and urea. Based on these findings, a tentative degradation pathway was proposed.


Assuntos
Corantes/química , Minerais/química , Ozônio/química , Água/química , Cromatografia Gasosa-Espectrometria de Massas , Soluções
7.
J Hazard Mater ; 144(1-2): 532-7, 2007 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-17141405

RESUMO

p-Nitrotoluene (PNT) is a nitroaromatic compound that is hazardous to humans and is a suspected hormone disrupter. The degradation of PNT in aqueous solution by ozonation (O(3)) combined with sonolysis (US) was investigated in laboratory-scale experiments in which pH, initial concentration of PNT, O(3) dose and temperature were varied. The degradation of PNT followed pseudo-first-order kinetics, and degradation products were monitored during the process. The maximum degradation was observed at pH 10.0. As the initial concentration of PNT decreased, the degradation rate increased. Both temperature and ozone dose had a positive effect on the degradation of PNT. Of the total organic carbon (TOC) reduction, 8, 68, and 85% were observed with US, O(3), and a combination of US and O(3) after reaction for 90 min, respectively, proving that ozonation combined with sonolysis for removal of TOC is more efficient than ozonation alone or ultrasonic irradiation alone. Major by-products, including p-cresol, 4-hydroxybenzaldehyde, 4-hydroxybenzoic acid, 4-(oxomethylene) cyclohexa-2,5-dien-1-one, but-2-enedioic acid, and acetic acid were detected by gas chromatography coupled with mass spectrometry.


Assuntos
Ozônio/química , Tolueno/análogos & derivados , Ultrassom , Poluentes Químicos da Água/química , Purificação da Água/métodos , Concentração de Íons de Hidrogênio , Soluções , Temperatura , Tolueno/química
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