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Cytogeographical variability within the Phleum pratense group in the Carpathians and adjacent part of Pannonian lowland, based on 132 populations analysed by flow cytometry, is described. Only diploid and hexaploid plants were detected among 635 samples from the studied area. Diploids were found to be less frequent (127 plants, 20%) than hexaploids (508, 80%). With the exception of the single pure diploid population, diploids always co-occured with hexaploids (30 localities, 22.7%). The majority of populations (101, 76.5%) consisted of hexaploid plants. Most mixed populations occur in the Western Carpathians (26). In the Eastern Carpathians, mixed populations are much rarer, with three populations in Ukraine and one in Romania. In the Southern Carpathians, only hexaploids occur. The conventional taxonomic concept of the two species, diploid P. bertolonii and hexaploid P. pratense , was followed in spite of their sympatric occurence. Distribution maps based on chromosome number data from previous studies and on ploidy level estimates are given for both species in the studied area. The pattern of different distribution of the two taxa within the Carpathians is discussed.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 475–485.  相似文献   
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Previous studies indicate that lumbar radicular pain following disc herniation may be associated with release of several pro-inflammatory mediators, including interleukin-1 (IL1). In the present study, we examined how genetic variability in IL1A (rs1800587 C>T), IL1B (rs1143627 T>C) and IL1RN (rs2234677 G>A) influenced the clinical outcome the first year after disc herniation. Patients (n = 258) with lumbar radicular pain due to disc herniation were recruited from two hospitals in Norway. Pain and disability were measured by visual analogue scale (VAS) and Oswestry Disability Index (ODI) over a 12 month period. The result showed that patients with the IL1A T allele, in combination with the IL1RN A allele had more pain and a slower recovery than other patients (VAS p = 0.049, ODI p = 0.059 rmANOVA; VAS p = 0.003, ODI p = 0.050 one-way ANOVA at 12 months). However, regarding the IL1B/IL1RN genotype, no clear effect on recovery was observed (VAS p = 0.175, ODI p = 0.055 rmANOVA; VAS p = 0.105, ODI p = 0.214 one-way ANOVA at 12 months). The data suggest that the IL1A T/IL1RN A genotype, but not the IL1B T/IL1RN A genotype, may increase the risk of a chronic outcome in patients following disc herniation.  相似文献   
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Gelatinases A and B, which are members of the matrix metalloproteinase (MMP) family, play essential roles in cancer development and metastasis, as they can break down basal membranes. Therefore, the determination and inhibition of gelatinases is essential for cancer treatment. Peptides that can specifically block each gelatinase may, therefore, be useful for cancer treatment. In this study, subtractive panning was carried out using a 12-mer peptide library to identify peptides that block gelatinase A activity (MMP-2), which is a key pharmacological target. Using this method, 17 unique peptide sequences were determined. MMP-2 inhibition by these peptides was evaluated through zymogram analyses, which revealed that four peptides inhibited MMP-2 activity by at least 65%. These four peptides were synthesized and used for in vitro wound healing using human umbilical vein endothelial cells, and two peptides, AOMP12 and AOMP29, were found to inhibit wound healing by 40%. These peptides are, thus, potential candidates for MMP-2 inhibition for cancer treatment. Furthermore, our findings suggest that our substractive biopanning screening method is a suitable strategy for identifying peptides that selectively inhibit MMP-2.  相似文献   
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We report the design of a MRI reporter gene with applications to non-invasive molecular imaging. We modified mitochondrial ferritin to localize to the cell cytoplasm. We confirmed the efficient cellular processing of this engineered protein and demonstrated high iron loading in mammalian cells. The reporter’s intracellular localization appears as distinct clusters that deliver robust MRI contrast. We used this new reporter to image in vivo and ex vivo the gene expression in native olfactory sensory neurons in the mouse epithelium. This robust MRI reporter can facilitate the study of the molecular mechanisms of olfaction and to monitor intranasal gene therapy delivery, as well as a wide range of cell tracking and gene expression studies in living subjects.  相似文献   
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Autophagy and DNA repair are two essential biological mechanisms that maintain cellular homeostasis. Impairment of these mechanisms was associated with several pathologies such as premature aging, neurodegenerative diseases, and cancer. Intrinsic or extrinsic stress stimuli (e.g., reactive oxygen species or ionizing radiation) cause DNA damage. As a biological stress response, autophagy is activated following insults that threaten DNA integrity. Hence, in collaboration with DNA damage repair and response mechanisms, autophagy contributes to the maintenance of genomic stability and integrity. Yet, connections and interactions between these two systems are not fully understood. In this review article, current status of the associations and crosstalk between autophagy and DNA repair systems is documented and discussed.  相似文献   
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A manipulated increase in acid deposition (15 kg S ha−1), carried out for three months in a mature Scots pine (Pinus sylvestris) stand on a podzol, acidified the soil and raised dissolved Al at concentrations above the critical level of 5 mg l−1 previously determined in a controlled experiment with Scots pine seedlings. The induced soil acidification reduced tree fine root density and biomass significantly in the top 15 cm of soil in the field. The results suggested that the reduction in fine root growth was a response not simply to high Al in solution but to the depletion of exchangeable Ca and Mg in the organic layer, K deficiency, the increase in NH4:NO3 ratio in solution and the high proton input to the soil by the acid manipulation. The results from this study could not justify the hypothesis of Al-induced root damage under field conditions, at least not in the short term. However, the study suggests that a short exposure to soil acidity may affect the fine root growth of mature Scots pine.  相似文献   
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Activity of nucleolar organizer regions (NORs) of acrocentric chromosomes determined by Ag-staining was comparatively studied in 40 individuals of Bulgarian and 40 individuals of Russian populations. Chromosome 21 was found to be significantly more often stained in both populations. The other NORs did not differ significantly in staining from the means. No differences were noted between individual NORs, in respect of the intensity of Ag-staining in both populations, except chromosome 15 which showed markedly decreased staining capacity in Russians. The data obtained are compared with those published in literature concerning four other populations.  相似文献   
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Background  

Although the clinical results of autologous chondrocyte implantation for articular cartilage defects have recently improved as a result of advanced techniques based on tissue engineering procedures, problems with cell handling and scaffold imperfections remain to be solved. A new cell-sheet technique has been developed, and is potentially able to overcome these obstacles. Chondrocyte sheets applicable to cartilage regeneration can be prepared with this cell-sheet technique using temperature-responsive culture dishes. However, for clinical application, it is necessary to evaluate the characteristics of the cells in these sheets and to identify their similarities to naive cartilage.  相似文献   
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