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101.
Miriam Nannette Ebert Gabriele Beyer-Sehlmeyer Ute Monika Liegibel Tanja Kautenburger Thomas Walter Becker Beatrice Louise Pool-Zobel 《Nutrition and cancer》2013,65(1-2):156-164
Butyrate, one of the major products of gut fermentation, is known to inhibit proliferation, induce apoptosis and differentiation, and increase phase II enzyme activities in tumor cells, whereas little information is available on protective effects in less-transformed colon cells. The aim of this study was to investigate whether the chemoprotective mechanism of glutathione S-transferase (GST) induction by butyrate could also play a role in earlier stages of colon carcinogenesis and whether chemoresistance of cells toward the endogenous genotoxic risk factor 4-hydroxy-2-nonenal (HNE) could be a consequence of butyrate treatment. As cell models, we used the human tumor cell lines HT29 and HT29 clone 19A, a differentiated subclone with properties resembling primary colon cells. We determined the expression of GSTP1 protein (enzyme-linked immunosorbent assay), the major GST in HT29, GSTP1 mRNA (Northern blotting), GST activity, intracellular glutathione, and total protein. The genotoxic impact of HNE (100-200 μM) was compared in butyrate-treated and nontreated cells using single-cell microgel electrophoresis. Our results show that GSTP1 mRNA, GSTP1 protein, GST activity, and total protein were increased (1.2- to 2.5-fold) and glutathione levels were maintained after 24- 72 h of incubation with 4 mM butyrate. Moreover, a marked reduction of HNE-induced genotoxicity was caused by preincubation with butyrate. Butyrate also induced the phosphorylation of extracellular signal-regulated kinases (ERK1/2, Western blotting) after 5-30 min, which indicates a regulation of GST expression by this signal pathway. Most effects were greater in HT29 parent cells than in clone cells. In conclusion, butyrate enhances expression of GST and other proteins in both cell lines, which leads to an enhanced chemoprotection, reducing the impact of HNE genotoxicity. Thus butyrate could play a role in early and later stages of cancer prevention by reducing exposure to relevant risk factors. 相似文献
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Orit Taubman – Ben-Ari Miriam Chasson Salam Abu-Sharkia 《Health & social care in the community》2021,29(5):1409-1419
The study examined two angles of childbirth anxieties of Jewish and Arab pregnant women in Israel during the COVID-19 pandemic (March-April, 2020). Specifically, we examined the contribution of personal resources: self-compassion and perceived social support, as well as a couple of COVID-19-related fears of being infected and concern for the foetus, to both the woman's global fear of childbirth (FOC) and her COVID-19-related childbirth anxiety. Participants were Jewish and Arab pregnant women (n = 403) aged 20–47, who completed a set of structured self-report questionnaires from 18 March to 9 April 2020. Findings indicated that Arab women reported higher level of COVID-19-related childbirth anxiety and COVID-19-related fears of being infected and concern for the foetus. In addition, poorer health, being an Arab woman, being in the third trimester, lower self-compassion, and higher COVID-19-related fears contributed significantly to greater COVID-19-related childbirth anxiety. Furthermore, poorer health, being primiparous, at-risk pregnancy, lower self-compassion and higher fear of being infected contributed significantly to greater FOC. Importantly, social support was found to moderate the association between self-compassion and FOC. The results highlight the need to be attentive to pregnant women in times of crisis, and in particular to especially vulnerable subgroups, such as cultural minorities. They also highlight the importance of personal resources that may be applied in targeted interventions to reduce distress in vulnerable populations. 相似文献
103.
Leah Cuthbertson Imogen Felton Phillip James Michael J. Cox Diana Bilton Silke Schelenz Michael R. Loebinger William O.C. Cookson Nicholas J. Simmonds Miriam F. Moffatt 《Journal of cystic fibrosis》2021,20(2):295-302
BackgroundThe prevalence of fungal disease in cystic fibrosis (CF) and non-CF bronchiectasis is increasing and the clinical spectrum is widening. Poor sensitivity and a lack of standard diagnostic criteria renders interpretation of culture results challenging. In order to develop effective management strategies, a more accurate and comprehensive understanding of the airways fungal microbiome is required. The study aimed to use DNA sequences from sputum to assess the load and diversity of fungi in adults with CF and non-CF bronchiectasis.MethodsNext generation sequencing of the ITS2 region was used to examine fungal community composition (n = 176) by disease and underlying clinical subgroups including allergic bronchopulmonary aspergillosis, chronic necrotizing pulmonary aspergillosis, non-tuberculous mycobacteria, and fungal bronchitis. Patients with no known active fungal disease were included as disease controls.ResultsITS2 sequencing greatly increased the detection of fungi from sputum. In patients with CF fungal diversity was lower, while burden was higher than those with non-CF bronchiectasis. The most common operational taxonomic unit (OTU) in patients with CF was Candida parapsilosis (20.4%), whereas in non-CF bronchiectasis sputum Candida albicans (21.8%) was most common. CF patients with overt fungal bronchitis were dominated by Aspergillus spp., Exophiala spp., Candida parapsilosis or Scedosporium spp.ConclusionThis study provides a framework to more accurately characterize the extended spectrum of fungal airways diseases in adult suppurative lung diseases. 相似文献
104.
Miriam E. Gerlofs-Nijland Jan A. M. A. Dormans Henk J. T. Bloemen Daan L. A. C. Leseman A. John F. Boere Frank J. Kelly 《Inhalation toxicology》2013,25(13):1055-1069
Residence in urban areas with much traffic has been associated with various negative health effects. However, the contribution of traffic emissions to these adverse health effects has not been fully determined. Therefore, the objective of this in vivo study is to compare the pulmonary and systemic responses of rats exposed to particulate matter (PM) obtained from various locations with contrasting traffic profiles. Samples of coarse (2.5 μm–10 μm) and fine (0.1 μm–2.5 μm) PM were simultaneously collected at nine sites across Europe with a high-volume cascade impactor. Six PM samples from various locations were selected on the basis of contrast in in vitro analysis, chemical composition, and traffic profiles. We exposed spontaneously hypertensive (SH) rats to a single dose (3 mg PM/kg body weight or 10 mg PM/kg body weight) of either coarse or fine PM by intratracheal instillation. We assessed changes in biochemical markers, cell differentials, and histopathological changes in the lungs and blood 24 h postexposure. The dose-related adverse effects that both coarse and fine PM induced in the lungs and vascular system were mainly related to cytotoxicity, inflammation, and blood viscosity. We observed clear differences in the extent of these responses to PM from the various locations at equivalent dose levels. There was a trend that suggests that samples from high-traffic sites were the most toxic. It is likely that the toxicological responses of SH rats were associated with specific PM components derived from brake wear (copper and barium), tire wear (zinc), and wood smoke (potassium). 相似文献
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A randomized controlled pilot study feasibility of a tablet‐based guided audio‐visual relaxation intervention for reducing stress and pain in adults with sickle cell disease 下载免费PDF全文
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