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131.
The production of chemicals from bio-based feedstocks is an emerging field of research in both industrial and academic communities. Here we present the synthesis of propylene glycol through catalytic hydrogenolysis of glycidol, obtained using a side-stream from the bio-based epichlorohydrin production plant, over Pd/C catalyst. In particular, we show the prominent effect of the acidic resin Amberlyst-15 in the selective and quantitative conversion of glycidol that permits to reach a TOF value of 162 h?1. Propylene glycol is obtained with high yields and selectivity (> 99%) in only 1 h under mild reaction conditions. The effect of solvent is also investigated giving interesting results on the reaction selectivity. The catalytic system (Pd/C + Amberlyst-15) shows a good recyclability also after seven reaction cycles reaching high performances in term of conversion and selectivity. This allowed minimizing the amount of waste and enhancing the efficiency of the whole system.  相似文献   
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Increased telomerase expression has been implicated in the pathogenesis of lung cancer and, since the primary cause of lung cancer is smoking, an association between telomerase reactivation and tobacco smoke has been proposed. In this work an investigation has been performed to assess the relationship between tobacco smoke exposure and telomerase activity (TA) in peripheral blood mononuclear cells of healthy smokers. The methylation status of the catalytic subunit of telomerase hTERT was concurrently investigated to assess the possible association between epigenetic modifications of hTERT and TA. Besides, the association between smoke and telomere length (TL) has been evaluated. Healthy monozygotic twins with discordant smoking habits were selected as study population to minimize inter‐individual differences because of demographic characteristics and genetic heterogeneity. Statistically significant higher values of TA and TL were observed in smokers compared to nonsmoker co‐twins. The multivariate analysis of data showed, besides smoking habits (P = 0.02), an influence of gender (P = 0.006) and BMI (P = 0.001) on TA and a borderline effect of gender (P = 0.05) on TL. DNA methylation analysis, focused on 100 CpG sites mapping in hTERT, highlighted nine CpG sites differentially methylated in smokers. When co‐twins were contrasted, selecting as variables the intra‐twin difference in TA and hTERT DNA methylation, a statistically significant inverse correlation (P = 0.003) was observed between TA and DNA methylation at the cg05521538 site. In conclusion, these results indicate an association of tobacco smoke with TA and TL and suggest a possible association between smoke‐induced epigenetic effects and TA in healthy smokers. Environ. Mol. Mutagen. 58:551–559, 2017. © 2017 Wiley Periodicals, Inc.  相似文献   
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Endometriosis, an estrogen-dependent chronic gynecological disease in women of reproductive age, is characterized by a systemic inflammation status involving also red blood cells (RBCs). In this study, we evaluated how the protein oxidative status could be involved in the worsening of RBC conditions due to dapsone intake in endometriotic women in potential treatment for skin or infection diseases. Blood samples from two groups of volunteers, control group (CG) and endometriosis patient group (PG), were analyzed for their content of band 3 tyrosine phosphorylation (Tyr-P) and high molecular weight aggregate (HMWA) in membranes, and glutathione (GSH) content and carbonic anhydrase (CA) activity in cytosol. In endometriotic patients, RBC showed the highest level of oxidative-related alterations both in membrane and cytosol. More interestingly, the addition of dapsone hydroxylamine (DDS-NHOH) could induce further increase of both membranes and cytosol markers, with an enhancement of CA activity reaching about 66% of the total cell enzyme amount. In conclusion, in PG the systemic inflammatory status leads to the inability of counteracting adjunctive oxidative stress, with a potential involvement of CA-related pathologies, such as glaucoma. Hence, the importance of the evaluation of therapeutic approaches worsening oxidative imbalance present in PG RBC is underlined.  相似文献   
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Dysmetabolic iron overload syndrome is a rare event causing hepatic impairment with serious long‐term side effects. Here, we describe a case of metabolic syndrome‐related hepatic iron overload that showed a rapid, effective, and safe response to erythrocytapheresis. J. Clin. Apheresis 31:443–447, 2016. © 2015 Wiley Periodicals, Inc.  相似文献   
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