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This work presents the Dauco carotae-Crepidetum rhoeadifoliae plant association, which is new to Poland. The association has been observed in industrial reclamation areas in the vicinity of carbonate mineral excavation sites in the central part of the Opole region. In the vast majority of cases, plots of this association developed in reclaimed areas. The majority of diagnostic species for the association was found within surveyed plots, including Verbascum thapsus, V. densiflorum and Bryum argenteum. Taxa characteristic of the alliance were also constantly present, i.e. Daucus carota, Melilotus alba, M. officinalis, Echium vulgare and Erysimum hieracifolium. This association belongs to the rarest syntaxa in Poland included in the Dauco-Melilotion alliance of ruderal communities with a predominance of hemicryptophytes, therophytes and perennials. The main diagnostic species — Crepis rhoeadifolia, belongs to very rare elements of Polish flora. It has been observed only in the southern part of the country in approx. 20 sites. Crepis rhoeadifolia had not been observed in Silesia for approx. 40 years, which is why it was considered to be an extinct taxon in this region. Rediscovering of the species allowed for diagnosing the Dauco-Crepidetum rhoeadifoliae association. This association is an example of a pioneer phytocenosis of, most likely, anthropogenic origin in Silesia.  相似文献   
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Diseases that are caused by non-tuberculous mycobacteria (NTM) continue to pose difficult clinical problems, and the epidemiological aspect of NTM-caused diseases is of great importance. In the case of Mycobacterium gordonae there is no adequate genotyping scheme. Here we present a potential rapid and reproducible genetic assay that uses trinucleotide repeat sequence-based PCR (TRS-PCR) for genotyping M. gordonae. The proposed method constitutes a useful single-primer PCR screen for genotyping this species. Among 10 TRS-containing primers, after applying (CAC)4-based PCR to 36 strains of M. gordonae, we found a discriminatory index of 0.975. The accuracy of this analysis was supported by a reasonable reproducibility of 92%. These results were compared with the Enterobacterial Repetitive Intergenic Consensus Sequences (ERIC)-PCR typing scheme which had lower discriminatory index of 0.93 and its reproducibility was only 86.3%.  相似文献   
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Oxidation of protein methionines to methionine sulfoxides can result in protein structural alterations with a wide variety of biological implications. Factors that determine susceptibility to oxidation are not well understood. The recent JBC Editors Pick by Walker et al. applied proteomic methodologies to show that the oxidative susceptibility of buried methionine residues is strongly correlated with folding stability of the contextual peptide. Proteome-wide analysis of oxidation-susceptible methionines promises to answer open questions about the biological functions of reversible methionine oxidation.  相似文献   
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Different low-molecular-weight thiols, including glutathione, cysteine, and cysteinylglycine are physiological free radical scavengers. On the other hand, homocysteine may play a role as an oxidant. The aim of our present study was to establish in vitro the effects of the commercial extract of Aronia melanocarpa (Aronox?) on the amount of selected low-molecular-weight thiols and the activity of antioxidative enzymes (superoxide dismutase, glutathione peroxidase, and glutathione reductase) in plasma obtained from patients with invasive breast cancer during different phases of treatment [before or after the surgery and patients after different phases of chemotherapy (doxorubicin and cyclophosphamide)] and from healthy subjects. Patients were hospitalized in Department of Oncological Surgery and Department of Chemotherapy, Medical University of Lodz, Poland. The level of low-molecular-weight thiols was determined by high-performance liquid chromatography. We observed that in the presence of the Aronia extract changes in amount of thiols in plasma from breast cancer patients (at all tested groups) were significantly reduced. Our results showed that tested commercial extract reduced modifications of antioxidative enzymes activity in plasma from patients during different phases of treatment, but this effect was not statistical significant. Our results suggest that the Aronia extract supplementation in breast cancer patients has a beneficial effect on thiols concentration in plasma. Plasma, as reported in this work, could be used as an experimental model to evaluate the beneficial action of plant supplements, including phenolic extracts on thiols or other molecules during different phases of treatment.  相似文献   
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The administration of melatonin, either peripherally (0.01-10 mg/kg) or intraocularly (0.001-10 mumol/eye), to light-exposed chicks dose-dependently increased serotonin N-acetyltransferase (NAT) activity in retina but not in pineal gland. The effect of melatonin was slightly but significantly reduced by luzindole (2-benzyl-N-acetyltryptamine), and not affected by two other purported melatonin antagonists, N-acetyltryptamine and N-(2,4-dinitrophenyl)-5-methoxytryptamine (ML-23). The elevation of the enzyme activity induced by melatonin was substantially stronger than that evoked by 5-hydroxytryptamine, N-acetyl-5-hydroxytryptamine, or 5-methoxytryptamine. The melatonin-evoked rise in the retinal NAT activity was counteracted by two dopamine D2 receptor agonists, quinpirole and apomorphine, and prevented by the dopamine D2 receptor blocker spiroperidol, and by an inhibitor of dopamine synthesis, alpha-methyl-p-tyrosine. Melatonin (0.1-10 mg/kg i.p.) dose-dependently decreased the levels of dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC), as well as the DOPAC/dopamine ratio, in chick retina but not in forebrain. The results obtained (1) indicate that melatonin in vivo potently inhibits dopamine synthesis selectively in retina, and (2) suggest that the increase in retinal NAT activity evoked by melatonin in light-exposed chicks is an indirect action of the compound, and results from the disinhibition of the NAT induction process from the dopaminergic (inhibitory) signal. The results provide in vivo evidence supporting the idea (derived on the basis of in vitro findings) that a mutually antagonistic interaction between melatonin and dopamine operates in retinas of living animals.  相似文献   
17.
Fulminant liver failure (FLF) consists of a cascade of events beginning with a presumed uncontrolled systemic activation of the immune system. The etiology of FLF remains undefined. In this study, we demonstrate that CCR5 deficiency promotes the development of acute FLF in mice following Con A administration by preventing activated hepatic CD1d-restricted NKT cells (but not conventional T cells) from dying from activation-induced apoptosis. The resistance of CCR5-deficient NKT cells from activation-induced apoptosis following Con A administration is not due to a defective Fas-driven death pathway. Moreover, FLF in CCR5-deficient mice also correlated with hepatic CCR5-deficient NKT cells, producing more IL-4, but not IFN-gamma, relative to wild-type NKT cells. Furthermore, FLF in these mice was abolished by IL-4 mAb or NK1.1 mAb treatment. We propose that CCR5 deficiency may predispose individuals to the development of FLF by preventing hepatic NKT cell apoptosis and by regulating NKT cell function, establishing a novel role for CCR5 in the development of this catastrophic liver disease that is independent of leukocyte recruitment.  相似文献   
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Background  

Normalization of gene expression data refers to the comparison of expression values using reference standards that are consistent across all conditions of an experiment. In PCR studies, genes designated as "housekeeping genes" have been used as internal reference genes under the assumption that their expression is stable and independent of experimental conditions. However, verification of this assumption is rarely performed. Here we assess the use of gene microarray analysis to facilitate selection of internal reference sequences with higher expression stability across experimental conditions than can be expected using traditional selection methods.  相似文献   
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