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661.
Enhanced expression of transforming growth factor-β1(TGF-β1) demonstrated in human colonic mucosa of patients with ulcerative colitis (UC), indicates its possible significance in the pathogenesis of this disease. The aim of this study was to evaluate plasma TGF-β1concentration in patients with different degrees of colonic mucosal injury, as a possible indicator of ulcerative colitis activity. TGF-β1concentration was measured with an enzyme immunoassay (EIA) in plasma of 45 patients with endoscopically confirmed UC. Values observed in UC patients (40.5±15.9 ng/ml) were significantly higher than in healthy people (18.3±11.6 ng/ml) and higher than in patients with irritable colon syndrome (ICS), (20.5±13.6 ng/ml). The highest plasma TGF-β1(58.6±112.1 ng/ml) was in patients with the severe UC course. TGF-β1level analysed in all UC patients revealed significant positive correlation with scored degree of mucosal injury (r=0.396;P<0.01). Among other possible laboratory markers of the disease activity, only C-reactive protein concentration demonstrated significant correlation. Enhanced production of TGF-β1can be related to inflammation activity. Measurement of plasma TGF-β1may be considered as a biomarker of the disease activity.  相似文献   
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663.
The effects of auxins and cytokinins at the range of concentrations 0.0001–100 µM on Acutodesmus obliquus (Chlorophyceae) cultures were studied. Microalga exhibited sensitivity to cytokinins in the following order: 0.01 µM tZ?>?0.1 µM Kin?>?1 µM DPU, whereas the hierarchy of auxin activity was: 0.01 µM IAA?>?0.1 µM IBA?>?0.1 µM PAA. Cytokinins possessed higher stimulating properties on the cell number, whereas auxins increased the size of cells. Differences in the metabolite profiles of the cultures treated with phytohormones were observed. Auxins and cytokinins had a positive effect on the photosynthetic apparatus enhancing the level of chlorophylls, carotenes, and xanthophylls. In comparison with auxins, cytokinins more effectively delayed oxidative damage by increasing the level of non-enzymatic antioxidants (ascorbate, glutathione) and the activity of enzymes scavenging reactive oxidative species (catalase, glutathione reductase, ascorbate peroxidase). On the other hand, auxins stimulated superoxide dismutase activity and provoked hydrogen peroxide generation, which may be involved in cell enlargement. All phytohormones reduced the content of abscisic acid and controlled the level of endogenous auxin and cytokinins suggesting complex interactions. Different dynamics of A. obliquus responses to auxins and cytokinins clearly demonstrated their diverse roles in algal growth and metabolism.  相似文献   
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665.
Soils collected in the proximity of a steel plant in Krakow were analyzed for their pH, the content of total organic carbon, and the total contents of metals and metalloids. Applying the Commission of European Communities Bureau of Reference (BCR) extraction of selected metals: Cd, Fe, Pb, and Zn, their forms of binding in soils have been determined. The results of the soil analyses of the samples taken in 1996 and 2016 were compared, and then the soil contamination changes were assessed using the GI, contamination factor (CF), and PLI indicators. A rehabilitation of the degraded soils was tested using the communal sewage sludge, which was added into the soil at four various ratios. The sewage sludge applied meets the environmental standards as a material for rehabilitating soils for non-agricultural needs but cannot be used for upgrading strongly contaminated soils. The reason is that the sludge addition increases the soil As, Ca, Cr, Mn, and Zn quantities as well as the easily mobilized fractions of the sludge/soil mixtures that contain Cd, Cr, Mg, Mn, Pb, and Tl. The addition of the communal sludge into soils increases the value of the environmental risk in the case of Pb, Mn, Mg, Fe, Cr, Zn, and Ca, but within the same risk classification ranges.  相似文献   
666.
Usher syndrome is rare genetic disorder impairing two human senses, hearing and vision, with the characteristic late onset of vision loss. This syndrome is divided into three types. In all cases, the vision loss is postlingual, while loss of hearing is usually prelingual. The vestibular functions may also be disturbed in Usher type 1 and sometimes in type 3. Vestibular areflexia is helpful in making a proper diagnosis of the syndrome, but, often, the syndrome is misdiagnosed as a nonsyndromic hearing loss. Here, we present a Polish family with hearing loss, which was clinically classified as nonsyndromic. After excluding mutations in the DFNB1 locus, we implemented the next-generation sequencing method and revealed that hearing loss was syndromic and mutations in the USH2A gene indicate Usher syndrome. This research highlights the importance of molecular analysis in establishing a clinical diagnosis of congenital hearing loss.  相似文献   
667.
Bcl-2/adenovirus E1B-19 kDa-interacting protein 3 (BNIP3) is an important mediator of cell survival and a member of the Bcl-2 family of proteins that regulate programmed cell death and autophagy. We have previously established a link between the expression of oncogenic HRas and up-regulation of BNIP3 and the control of autophagy in cancer cells. However, in view of varied expression of BNIP3 in different tumor types and emerging uncertainties as to the role of epigenetic silencing, oncogenic regulation and the role of BNIP3 in cancer are still poorly understood.  相似文献   
668.
This work demonstrates that self‐disproportionation of enantiomers via achiral chromatography can be recommended as inexpensive and general method for optical purification of enantiomerically enriched compounds. In particular, the advantage of this approach over conventional recrystallization is that it can be used for both crystalline as well as liquid compounds. Chirality, 25:365‐368, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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670.
Human immunodeficiency virus type 1 (HIV-1)-specific CD8+ T cells in early infection are associated with the dramatic decline of peak viremia, whereas their antiviral activity in chronic infection is less apparent. The functional properties accounting for the antiviral activity of HIV-1-specific CD8+ T cells during early infection are unclear. Using cytokine secretion and tetramer decay assays, we demonstrated in intraindividual comparisons that the functional avidity of HIV-1-specific CD8+ T cells was consistently higher in early infection than in chronic infection in the presence of high-level viral replication. This change of HIV-1-specific CD8+ T-cell avidity between early and chronic infections was linked to a substantial switch in the clonotypic composition of epitope-specific CD8+ T cells, resulting from the preferential loss of high-avidity CD8+ T-cell clones. In contrast, the maintenance of the initially recruited clonotypic pattern of HIV-1-specific CD8+ T cells was associated with low-level set point HIV-1 viremia. These data suggest that high-avidity HIV-1-specific CD8+ T-cell clones are recruited during early infection but are subsequently lost in the presence of persistent high-level viral replication.  相似文献   
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