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Abstract: Carbon dioxide was photo-catalytically reduced to produce formic acid in an aqueous solution using visible light irradiation. Titania and zinc-phthalocyanine (ZnPc)-loaded titania were synthesized by a sol–gel method and in situ chemical synthesis technique. The photo-catalytic reactions were conducted in a Pyrex reactor with a visible light irradiating. XRD and DRS revealed that ZnPc was on the TiO2 surface. The optimum technique was in situ chemical synthesis and the optimum amount of ZnPc loading was 1.0wt.% for the highest dispersion among catalysts. The formic acid yield of 1.0wt.% in situ ZnPc/TiO2 was 978.6μmol/g catalyst following 10h of visible light illumination and the conversion was 0.37%. The yield was higher than those of sol–gel TiO2 and ZnPc/BH-1, whose yields were 321.0 and 756.2μmol/g catalyst, respectively. Experimental results indicated that the formic acid yield was significantly increased by loading ZnPc. ZnPc has a higher selectivity than metal catalysts for the reduction of CO2. The photo-catalytic efficiency of ZnPc/TiO2 was markedly increased because of the lowering re-combination probability for hole–electron pairs. [Copyright &y& Elsevier]

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.

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.