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991.
The aim of this study was to assess the influence of cisplatin and an extremely low frequency electromagnetic field (ELF‐EMF) on antioxidant enzyme activity and the lipid peroxidation ratio, as well as the level of DNA damage and reactive oxygen species (ROS) production in AT478 carcinoma cells. Cells were cultured for 24 and 72 h in culture medium with cisplatin. Additionally, the cells were irradiated with 50 Hz/1 mT ELF‐EMF for 16 min using a solenoid as a source of the ELF‐EMF. The amount of ROS, superoxide dismutase (SOD) isoenzyme activity, glutathione peroxidase (GSH‐Px) activity, DNA damage, and malondialdehyde (MDA) levels were assessed. Cells that were exposed to cisplatin exhibited a significant increase in ROS and antioxidant enzyme activity. The addition of ELF‐EMF exposure to cisplatin treatment resulted in decreased ROS levels and antioxidant enzyme activity. A significant reduction in MDA concentrations was observed in all of the study groups, with the greatest decrease associated with treatment by both cisplatin and ELF‐EMF. Cisplatin induced the most severe DNA damage; however, when cells were also irradiated with ELF‐EMF, less DNA damage occurred. Exposure to ELF‐EMF alone resulted in an increase in DNA damage compared to control cells. ELF‐EMF lessened the effects of oxidative stress and DNA damage that were induced by cisplatin; however, ELF‐EMF alone was a mild oxidative stressor and DNA damage inducer. We speculate that ELF‐EMF exerts differential effects depending on the exogenous conditions. This information may be of value for appraising the pathophysiologic consequences of exposure to ELF‐EMF. Bioelectromagnetics 33:641–651, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
992.
Docosahexaenoic acid (DHA) potentially modulates inflammatory processes. Therefore, the aim of this study was to determine the influence of DHA supplementation on the expression of intestinal inflammation and nutritional status in rats which have undergone restorative proctocolectomy. Twenty-four Wistar rats were operated. After the induction of pouchitis, animals were randomly divided into a control group (CG) and supplementation groups receiving respectively a semi-synthetic diet without or with DHA (in a lower or higher dose, respectively known as the lower dose, LD, and higher dose, HD, groups) for six weeks. Selected nutritional parameters were assessed. Histopathological and immunohistochemical analysis of pouch mucosa specimens was also performed. The effectiveness of feeding and quality of stools were significantly better in the HD group than in the CG. The intensity of inflammation (Moskovitz scale) was higher in HD and LD than in CG (p = 0.03 and p = 0.0006, respectively). Nevertheless, pouch adaptation (Laumonier scale) was more significant in LD than in CG (p = 0.007). On the other hand, tissue expression of IL-1α and IL-10 was higher in HD and LD than in CG (IL-1α, p = 0.009 and p = 0.05, respectively; IL-10, p = 0.04 for both). DHA supplementation has no impact on body weight gain. Yet it seems that it may improve the effectiveness of nutrition and stool quality in rats which have undergone restorative proctocolectomy. Simultaneously, it increases the intensity of pouch adaptation and inflammation. The specificity of observed changes is not clear. However, it may imply potential modulation of inflammatory processes of pouch mucosa.  相似文献   
993.
This study deals with the influence of cadmium on the structure and function of ferredoxin:NADP(+) oxidoreductase (FNR), one of the key photosynthetic enzymes. We describe changes in the secondary and tertiary structure of the enzyme upon the action of metal ions using circular dichroism measurements, Fourier transform infrared spectroscopy and fluorometry, both steady-state and time resolved. The decrease in FNR activity corresponds to a gentle unfolding of the protein, caused mostly by a nonspecific binding of metal ions to multiple sites all over the enzyme molecule. The final inhibition event is most probably related to a bond created between cadmium and cysteine in close proximity to the FNR active center. As a result, the flavin cofactor is released. The cadmium effect is compared to changes related to ionic strength and other ions known to interact with cysteine. The complete molecular mechanism of FNR inhibition by heavy metals is discussed.Electronic supplementary material The online version of this article (doi:10.1007/s10867-012-9262-z) contains supplementary material, which is available to authorized users.  相似文献   
994.
Arkadiusz Sołtysiak 《HOMO》2012,63(2):110-113
Dental caries is an infectious disease caused by oral acidophilic bacteria feeding on fermentable sugars, e.g. Streptococcus mutans. The frequency of dental caries in Neandertals was very low. This was usually explained as the result of a low-sugar diet. Recent research, however, revealed some regional differences between European and Near Eastern Neandertals, with the latter consuming considerable amounts of plants including highly cariogenic dates. This discovery, compared with the results of research on genetic diversity of S. mutans, may suggest that this species, and perhaps other most virulent species, were absent in the oral flora of Neandertals.  相似文献   
995.
Birch pollen is one of the main causes of allergy during spring and early summer in northern and central Europe. The aim of this study was to create a forecast model that can accurately predict daily average concentrations of Betula sp. pollen grains in the atmosphere of Szczecin, Poland. In order to achieve this, a novel data analysis technique—artificial neural networks (ANN)—was used. Sampling was carried out using a volumetric spore trap of the Hirst design in Szczecin during 2003–2009. Spearman’s rank correlation analysis revealed that humidity had a strong negative correlation with Betula pollen concentrations. Significant positive correlations were observed for maximum temperature, average temperature, minimum temperature and precipitation. The ANN resulted in multilayer perceptrons 366 8: 2928-7-1:1, time series prediction was of quite high accuracy (SD Ratio between 0.3 and 0.5, R > 0.85). Direct comparison of the observed and calculated values confirmed good performance of the model and its ability to recreate most of the variation.  相似文献   
996.
Purinergic receptor P2X3 has been linked to analgesia in a number of pre-clinical models of pain, and is expressed in the human pain perception pathway. Only few P2X3-selective antagonists have been reported to date. This Letter describes the SAR and in vivo analgesic profile of a novel scaffold of selective P2X3 antagonists.  相似文献   
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The role of frugivorous birds in dispersal of the seeds of fleshy-fruited plants is well understood, but other groups of birds like granivores and omnivores can also act as vectors, especially in the process of non-standard dispersal. In this study we examined the role of two widely distributed birds (the Eurasian Blackbird, Turdus merula, and the Black Redstart, Phoenicurus ochruros) in seed dispersal. We analyzed the content of 279 droppings of the Black Redstart collected between July and October and 85 droppings of the Eurasian Blackbird collected during January. In total we found 366 seeds, representing 11 plant taxa, in the faecal samples; 93% of the seeds belonged to fleshy-fruited species. The most numerous were two native taxa, Sambucus racemosa/nigra, in summer and autumn, Crataegus monogyna in winter, and one alien species Morus alba, which is dispersed in summer. We also found seeds of four dry-fruited species; the most interesting of which was the presence of anemochorous seeds of Solidago gigantea (a highly invasive alien species). The seeds were found only in droppings of the Eurasian Blackbird. Considering the obtained results the need for further studies on bird-plant interactions should be a priority.  相似文献   
1000.
AimTo report the long-term follow-up of a cohort of adult patients with LGG post-operatively irradiated in one institution, and to identify prognostic factors for progression free survival.BackgroundThere is little consensus about the optimal treatment for low-grade glioma (LGG), and the clinical management of LGG is one of the most controversial areas in neurooncology. Radiation therapy is one option for treatment of patients with LGG, whereas other options include postoperative observation.Materials and methodsBetween 1975 and 2005, 180 patients with LGG (WHO II) received postoperative irradiation after non radical (subtotal or partial) excision. Patients had to be 18 years of age or older, and have histologic proof of supratentorial fibrillary (FA), protoplasmic (PA) or gemistocytic astrocytoma (GA). Radiotherapy was given within 3–10 weeks after surgery. Treatment fields were localized and included the preoperative tumor volume, with a 1–2 cm margin, treated to a total dose of 50–60 Gy in 25–30 fractions over 5–6 weeks.ResultsActuarial ten-year progression free survival (APFS) in the whole group was 19%. The worse prognosis was observed in patients with GA. Ten-year APFS rates for GA, PA and FA were 10%, 18% and 22%, respectively.ConclusionThe findings from our long-term cohort of 180 patients with LGG confirmed by uni- and multivariate analysis demonstrated that only astrocytoma histology significantly determined the prognosis. The best survival was observed in patients with the fibrillary variant, and the worst for the gemistocytic one.  相似文献   
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