Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Filtros adicionais











País/Região como assunto
Intervalo de ano
1.
J Nanosci Nanotechnol ; 20(2): 779-788, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383073

RESUMO

N and F co-doped La-TiO2 (La-TONF) samples were prepared through the solvothermal method by using HMT and NaF as precursors. The obtained samples were characterized by UV-Vis DRS, XRD, XPS and PL measurements for light-harvesting properties, crystal phase and optical characteristics, respectively. Interestingly, the TONF sample had a different fluorescence emission intensity than the TON or TOF samples, thus suggesting a clear synergistic effect of N and F co-doping. The optimal doping amount of La was 2 wt.%, and the absorption edge was red-shifted from 453 nm to 464 nm for La-TiO2 and La-TONF. The photocatalytic activity was evaluated by degradation of MO and oxidation of TMB under visible light irradiation. La-TONF exhibited excellent photocatalytic activity and a degradation rate of 92.4%, 4.4 times that of undoped TiO2 (20.8%). The photocatalytic degradation activity remained above 85.8%, even after five runs. In addition, the MO photodegradation catalyzed by La-TONF followed first order kinetics. According these results, a possible synergistic effect mechanism for the enhanced photocatalytic performance is proposed.

2.
J Nanosci Nanotechnol ; 18(5): 3306-3313, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442832

RESUMO

Fly ash is a solid waste discharged from thermal power plant. Specific surface area of floating fly ash cenospheres (FACs) would increase after it was modified. The photocatalytic composite of TiO2/FACs was successfully synthesized by sol-gel method using the carrier of modified FACs and tetrabutyl titanate as starting materials. The different influence factors on the photocatalytic performance of TiO2/FACs composites were characterized through SEM, EDS, XRD, UV-vis DRS and BET surface measurements. The UV-vis DRS spectra revealed that the absorption edge of TiO2 is 387 nm while that of TiO2/FACs photocatalysts red-shifts to 500 nm. Photocatalytic activity of TiO2/FACs was evaluated by the photocatalytic depigmentation of methyl orange solution (MO, 20 mg L-1, pH = 6.3) under visible light irradiation. It was found that the specific surface area, surface roughness and activity of FACs were increased by NaOH solution activation. The degradation rate of MO reaches 52% in 180 min under the visible light illumination. But too much FACs could decrease its photocatalytic activity and degradation rate. And the recovery test indicated that TiO2/FACs photocatalyst was rather stable, easy to recover from the treated wastewater.

3.
J Nanosci Nanotechnol ; 18(3): 1675-1681, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448644

RESUMO

Metal ions (Cr, Ni, Co) doped titania (M-TiO2) coupled with the long after glow phosphor MgAl2O4:(Pr3+, Dy3+) particles were synthesized by the sol-gel method, with the best mass ratio of MgAl2O4:(Pr3+, Dy3+) to M-TiO2 as 4:6. MgAl2O4:(Pr3+, Dy3+)/M-TiO2 had the persistent methyl orange (MO) photocatalytic degradation ability and the photocatalytic degradation went on reacting more than 90 min in dark after turning off the light. MgAl2O4:(Pr3+, Dy3+) emitted the light as a light source in dark which was absorbed by M-TiO2. The differences of MgAl2O4:(Pr3+, Dy3+)/Cr-TiO2, MgAl2O4:(Pr3+, Dy3+)/Ni-TiO2 and MgAl2O4:(Pr3+, Dy3+)/Co-TiO2 might be attributed to the difference in the metal ions doping. The composite MgAl2O4:(Pr3+, Dy3+)/Cr-TiO2 revealed the highest ability of persistent photocatalytic degradation methyl orange. Different metal ions doping made the TiO2 with different band gap.

4.
Bioengineered ; 8(6): 723-731, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-28708015

RESUMO

Peripheral muscle dysfunction is an important complication in patients with chronic obstructive pulmonary disease (COPD). The objective of this study was to explore the relationship between the levels of peroxisome proliferator-activated receptor α (PPARα) mRNA expression and the respiratory function and ultrastructure of mitochondria in the vastus lateralis of patients with COPD. Vastus lateralis biopsies were performed on 14 patients with COPD and 6 control subjects with normal lung function. PPARα mRNA levels in the muscle tissue were detected by real-time PCR. A Clark oxygen electrode was used to assess mitochondrial respiratory function. Mitochondrial number, fractional area in skeletal muscle cross-sections, and Z-line width were observed via transmission electron microscopy. The PPARα mRNA expression was significantly lower in COPD patients with low body mass index (BMIL) than in both COPD patients with normal body mass index (BMIN) and controls. Mitochondrial respiratory function (assessed by respiratory control ratio) was impaired in COPD patients, particularly in BMIL. Compared with that in the control group, mitochondrial number and fractional area were lower in the BMIL group, but were maintained in the BMIN group. Further, the Z-line became narrow in the BMIL group. PPARα mRNA expression was positively related to mitochondrial respiratory function and volume density. In COPD patients with BMIN, mitochondria volume density was maintained, while respiratory function decreased, whereas both volume density and respiratory function decreased in COPD patients with BMIL. PPARα mRNA expression levels are associated with decreased mitochondrial respiratory function and volume density, which may contribute to muscle dysfunction in COPD patients.


Assuntos
Mitocôndrias/metabolismo , Músculo Esquelético/metabolismo , PPAR alfa/genética , Doença Pulmonar Obstrutiva Crônica/metabolismo , RNA Mensageiro/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias/genética , Estresse Oxidativo/genética , Estresse Oxidativo/fisiologia , Doença Pulmonar Obstrutiva Crônica/genética
5.
Artigo em Inglês | MEDLINE | ID: mdl-25999707

RESUMO

BACKGROUND: The role of the antioxidant N-acetylcysteine (NAC) in the treatment of chronic obstructive pulmonary disease (COPD) has not been clarified as yet. In early studies, we found that the proportion of smokers with COPD having extremely slow/slow microsomal epoxide hydrolase (EPHX1) enzyme activity is significantly higher than that in healthy smokers. The purpose of this study was to evaluate whether different EPHX1 enzyme activity is related to differential therapeutic effects of treatment with NAC in COPD. METHODS: A total of 219 patients with COPD were randomly allocated to an extremely slow/slow EPHX1 enzyme activity group (n=157) or a fast/normal EPHX1 enzyme activity group (n=62) according to their EPHX1 enzyme activity. Both groups were treated with NAC 600 mg twice daily for one year. The main study parameters, including forced expiratory volume in one second (FEV1), St George's Respiratory Questionnaire (SGRQ), and yearly exacerbation rate, were measured at baseline and at 6-month intervals for one year. RESULTS: Both FEV1 and SGRQ symptom scores were improved after treatment with NAC in the slow activity group when compared with the fast activity group. Further, changes in FEV1 and SGRQ symptom score in patients with mild-to-moderate COPD were more significant than those in patients with severe-to-very severe COPD. The yearly exacerbation rates were reduced in both groups, but the reduction in the slow activity group was significantly lower than in the fast activity group. CONCLUSION: NAC treatment in COPD patients with extremely slow/slow EPHX1 enzyme activity improves FEV1 and the SGRQ symptom score, especially in those with mild-to-moderate COPD, and polymorphism in the EPHX1 gene may have a significant role in differential responses to treatment with NAC in patients with COPD.


Assuntos
Acetilcisteína/administração & dosagem , Antioxidantes/administração & dosagem , Epóxido Hidrolases/genética , Pulmão/efeitos dos fármacos , Polimorfismo Genético , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Idoso , Progressão da Doença , Esquema de Medicação , Epóxido Hidrolases/metabolismo , Feminino , Volume Expiratório Forçado , Humanos , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Farmacogenética , Fenótipo , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/enzimologia , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Recuperação de Função Fisiológica , Índice de Gravidade de Doença , Espirometria , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento
6.
Zhonghua Yi Xue Za Zhi ; 93(28): 2191-4, 2013 Jul 23.
Artigo em Chinês | MEDLINE | ID: mdl-24169326

RESUMO

OBJECTIVE: To explore the relationship between the mRNA expression level of mitochondrial cytochrome oxidase and the maternal inheritance of asthma. METHODS: From January to December 2009, 220 asthma patients, 162 patient kins and 260 healthy subjects were recruited from Departments of Respiratory Critical Care Medicine and Pediatric Medicine at First Affiliated Hospital, Kunming Medical College. Lung function tests were performed and serum IgE level measured. The polymorphism of mitochondrial cytochrome oxidase gene polymorphisms was detected by direct sequencing. And the peripheral level of COX mRNA was measured by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: No significant difference existed in age, gender among 3 groups. For 3 groups, the first second forced expiratory volume (FEV1)/forced vital capacity (FVC) were 90.6 ± 6.2, 92.3 ± 2.3, 102.3 ± 2.3 and FEV1 percentage of expected value (FEV1%) were (82.9 ± 10.8)%, (94.8 ± 5.4)% and (98.3 ± 8.6)% respectively. The lung function was not significant difference among three groups. The mRNA expression level of mitochondrial cytochrome oxidase in peripheral blood were 0.357 ± 0.217, 0.637 ± 0.473 and 0.975 ± 0.260 in the asthma, kin and control groups respectively. No significant difference existed in the expression level of COX3 mRNA among 3 groups (F = 21.45, P = 0.012). The serum level of lgE was the highest for the asthma patients. And it was significantly higher in the asthma group than that in the control group ((283.6 ± 62.4) vs (52.3 ± 13.7) µg/L, F = 48.31, P < 0.05). Moreover, the serum level of IgE was significantly higher in the kin group than that in the control group ((116.4 ± 57.5) vs (52.3 ± 13.7) µg/L, F = 20.45, P < 0.05). However, there was a negative correlation between the mRNA expression level of mitochondrial cytochrome oxidase and the serum level of IgE among 3 groups. CONCLUSIONS: The down-regulated mRNA expressin of mitochondrial cytochrome oxidase may participate in allergic inflammation by regulating the level of IgE. And the maternal inheritance of asthma is in effect.


Assuntos
Asma/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Predisposição Genética para Doença , RNA Mensageiro/genética , Humanos , RNA Mitocondrial , Testes de Função Respiratória , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
Respirology ; 16(8): 1221-7, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21801278

RESUMO

BACKGROUND AND OBJECTIVE: Adrenergic ß2 receptors (ADRB2) play an important role in regulating pulmonary function. Many previous studies have investigated possible associations between polymorphisms in the ADRB2 gene and asthma, but have yielded conflicting results. Furthermore, little is known regarding the possible role of the Arg19Cys polymorphism in susceptibility to asthma among Chinese. METHODS: This case-control association study involved 238 patients with asthma and 265 healthy subjects from a Han population in southwest China. For all subjects, the 5' leader cistron Arg19Cys, Arg16Gly and Gln27Glu polymorphisms in the ADRB2 gene were characterized by direct sequencing. Genotype, allele and haplotype frequencies were determined. In addition, to evaluate the association between the ADRB2 polymorphisms and lung function, bronchodilator response to inhaled ß2 agonists (400 µg of albuterol) was assessed in the asthmatic patients. RESULTS: There were no significant differences in genotype or allele frequencies for the three ADRB2 polymorphisms between the two cohorts. The Arg19/Arg16/Gln27 haplotype was more frequent among asthmatic patients than control subjects (odds ratio 2.24, 95% confidence interval (CI): 1.05-4.73, P=0.04). Moreover, the Arg19/Cys19 genotype was associated with a lower FEV1% (mean difference -4.5, 95% CI: -12.5 to 3.6, P=0.02) and FEV1/FVC (mean difference 8.9, 95% CI: 8.5-9.4, P=0.01). The bronchodilator response to albuterol was also marginally lower in individuals who were homozygous for the Arg19 genotype (mean difference 4.2, 95% CI: 3.7-4.8, P=0.03). CONCLUSIONS: The Arg19/Cys19 genotype was an independent risk factor for lower FEV1% and FEV1/FVC. Asthmatic patients with the Arg19/Arg19 genotype showed decreased responsiveness to albuterol. Furthermore, the Arg19/Arg16/Gln27 haplotype may contribute to increased susceptibility to asthma in the Chinese population.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Asma/etnologia , Asma/genética , Polimorfismo de Nucleotídeo Único , Receptores Adrenérgicos beta 2/genética , Agonistas de Receptores Adrenérgicos beta 2/uso terapêutico , Albuterol/uso terapêutico , Arginina , Asma/tratamento farmacológico , Broncodilatadores/uso terapêutico , Estudos de Casos e Controles , China/epidemiologia , Feminino , Volume Expiratório Forçado , Regulação da Expressão Gênica , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Glutamina , Haplótipos , Humanos , Desequilíbrio de Ligação/genética , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética
8.
Zhonghua Jie He He Hu Xi Za Zhi ; 31(11): 811-4, 2008 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-19080533

RESUMO

OBJECTIVE: To observe the efficacy of combination therapy with inhaled salmeterol/fluticasone and tiotropium in reducing the frequency of acute episodes of symptom exacerbation and improving lung function and health status in chronic obstructive pulmonary disease (COPD). METHODS: One hundred and twenty-six patients (M/F: 92/34) with COPD were treated in a randomised, parallel-group, controlled study with salmeterol/fluticasone (50/250 microg) twice daily and tiotropium 18 microg once daily (n = 33, M/F: 23/10); salmeterol/fluticasone (50/250 microg) twice daily (n = 32, M/F: 24/8); or tiotropium 18 microg once daily (n = 32, M/F: 23/9) for 12 months. Patients in the blank control group (n = 29, M/F: 22/7) did not receive any inhaled anticholinergic drugs, long-acting beta(2) agonists or glucocorticoid therapy. Intention-to-treat analysis (n = 161) and per-protocol analysis (n = 126, age 45 - 71 years) were performed. RESULTS: Three active treatments significantly improved symptoms and health status. The use of rescue medication in the combination group [1 (0 - 7) time, 95% CI] was significantly decreased compared with those in the blank group [2 (0 - 29) times], salmeterol/fluticasone alone [2 (0 - 13) times], tiotropium alone [1 (0 - 11) time], F = 4.914, P < 0.01. The frequency of exacerbations in the combination group was (0.7 +/- 0.5) time, significantly lower than that in the blank group [(1.5 +/- 0.9) times], salmeterol/fluticasone alone [(1.2 +/- 0.6) times], and tiotropium alone [(1.1 +/- 0.5) times], F = 8.513, P < 0.01. The FEV(1) in the combination group after the trial was (1.19 +/- 0.03) L, significantly improved compared to that before treatment (1.09 +/- 0.04) L, a 9.5% increase, which was greater than the blank (0.9%), tiotropium alone (8.2%) and salmeterol/fluticasone alone (6.3%), t = -5.024 to -15.58, P < 0.01. CONCLUSION: Combination therapy with salmeterol/fluticasone and tiotropium leads to better control of symptoms and improved lung function, with no greater risk of side-effects, as compared to salmeterol/fluticasone or tiotropium alone in the treatment of COPD.


Assuntos
Agonistas Adrenérgicos beta/uso terapêutico , Albuterol/análogos & derivados , Androstadienos/uso terapêutico , Antagonistas Colinérgicos/uso terapêutico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Derivados da Escopolamina/uso terapêutico , Administração por Inalação , Idoso , Albuterol/administração & dosagem , Albuterol/uso terapêutico , Androstadienos/administração & dosagem , Quimioterapia Combinada , Feminino , Fluticasona , Humanos , Masculino , Pessoa de Meia-Idade , Xinafoato de Salmeterol , Derivados da Escopolamina/administração & dosagem , Brometo de Tiotrópio
9.
Artigo em Chinês | MEDLINE | ID: mdl-18199396

RESUMO

OBJECTIVE: To study the diagnostic and prognostic value of procalcitonin (PCT), common inflammatory markers combining with scores for estimating organ failure of infection related organs (SOFA) in patients with sepsis in early stage. METHODS: Patients were observed continuously in a perspective study with diagnostic tests. According to the definition of ACCP/SCCM Consensus Conference, patients were classified into 5 groups, including non-systemic inflammatory response syndrome (SIRS) (control) group, SIRS group, sepsis group, severe sepsis group and septic shock group. Indexes of inflammation, SOFA and concentration of PCT were determined at 24 hours, and their correlation was analyzed. RESULTS: Two hundred and eight patients were enrolled, including 59 in non-SIRS group, 57 in SIRS group, 52 in sepsis group, 28 in severe sepsis group and 12 in septic shock group. PCT concentrations were positively correlated with the severity of sepsis. Spearman's correlation coefficient was 0.909 (P=0.000). According to the receiver operating characteristic curves (ROC-curves) analysis principle, ROC curves were drawn and areas under these curves (AUC) was calculated. In the diagnosis of sepsis, AUC values were 0.936+/-0.020 for PCT, 0.973+/-0.011 for SOFA (both P=0.000). The best cutoff values in the diagnosis of sepsis were 0.375 microg/L for PCT, and 3. 5 for SOFA score. The Youden index of PCT and SOFA scores was 0.808 and 0.801, respectively. Binary Logistic regression analysis confirmed that PCT and SOFA score were highly correlated with sepsis (OR=84.794,10.761, respectively, both P=0.000) after eliminating confusion factors including age and C-reactive protein (CRP) etc.. PCT and SOFA score could be used to predict the incidence of sepsis. SOFA score was the best prognostic indicator of sepsis (OR=2.084, P=0.0002). CONCLUSION: The traditional inflammatory markers and CRP are useful parameters to differentiate SIRS from non-SIRS, but are not reliable indicators for the early diagnosis in patients with sepsis. PCT is more specific indicator in early diagnosis of sepsis to differentiate from SIRS. PCT combining with SOFA score can be used to predict the incidence of sepsis. SOFA score can be used to define objectively the severity of sepsis according to PCT level and is helpful for estimation of prognosis in patients with sepsis.


Assuntos
Biomarcadores/sangue , Calcitonina/sangue , Precursores de Proteínas/sangue , Sepse/diagnóstico , Peptídeo Relacionado com Gene de Calcitonina , Diagnóstico Precoce , Humanos , Prognóstico , Estudos Prospectivos , Sepse/sangue
10.
Chin Med J (Engl) ; 120(1): 12-6, 2007 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-17254481

RESUMO

BACKGROUND: Recent studies have suggested that susceptibility to chronic obstructive pulmonary disease (COPD) might be related to the length polymorphism of (GT)(n) repeat in the 5'-flanking region of heme oxygenase-1 (HOX-1) gene. However, there has been no research about the relationship between the polymorphism of HOX-1 gene and severity of COPD. METHODS: The polymorphism of HOX-1 gene in 452 patients with COPD from Han population in Southwest China was analysed by fragment analysis. The frequencies of the HOX-1 genotype were compared with the stage of COPD of each patient. RESULTS: The HOX-1 genotypes were classified into two groups: group I were individuals with class L allele (the number of GT = 32 repeats), and group II were those without class L allele (the number of GT < 32 repeats). The genotypic frequency of the HOX-1 group I was significantly higher than group II in the very severe COPD patients (36.8% vs 22.4%, P < 0.01, OR = 2.0, 95% CI 1.3 - 3.1), while the genotypic frequency of the HOX-1 group II was lower in the mild COPD (16.0% vs 26.0%, P = 0.02, OR = 0.5, 95% CI 0.3 - 0.9). However, in moderate and severe stages COPD, there were similar genotypic frequencies between HOX-1 group I and group II. CONCLUSIONS: Genetic polymorphism in HOX-1 is associated with the severity of COPD in Southwest China. COPD patients with class L allele may be susceptible to develop very severe COPD. Conversely, the COPD patients without class L allele may be more easily stabilized on mild COPD.


Assuntos
Heme Oxigenase-1/genética , Polimorfismo Genético , Doença Pulmonar Obstrutiva Crônica/enzimologia , Adulto , Idoso , Feminino , Volume Expiratório Forçado , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/fisiopatologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA