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191.
Astrid V. Stronen Bogumi?a J?drzejewska Cino Pertoldi Ditte Demontis Ettore Randi Magdalena Niedzia?kowska Ma?gorzata Pilot Vadim E. Sidorovich Ihor Dykyy Josip Kusak Elena Tsingarska Ilpo Kojola Alexandros A. Karamanlidis Aivars Ornicans Vladimir A. Lobkov Vitalii Dumenko Sylwia D. Czarnomska 《PloS one》2013,8(10)
European wolves (Canis lupus) show population genetic structure in the absence of geographic barriers, and across relatively short distances for this highly mobile species. Additional information on the location of and divergence between population clusters is required, particularly because wolves are currently recolonizing parts of Europe. We evaluated genetic structure in 177 wolves from 11 countries using over 67K single nucleotide polymorphism (SNP) loci. The results supported previous findings of an isolated Italian population with lower genetic diversity than that observed across other areas of Europe. Wolves from the remaining countries were primarily structured in a north-south axis, with Croatia, Bulgaria, and Greece (Dinaric-Balkan) differentiated from northcentral wolves that included individuals from Finland, Latvia, Belarus, Poland and Russia. Carpathian Mountain wolves in central Europe had genotypes intermediate between those identified in northcentral Europe and the Dinaric-Balkan cluster. Overall, individual genotypes from northcentral Europe suggested high levels of admixture. We observed high diversity within Belarus, with wolves from western and northern Belarus representing the two most differentiated groups within northcentral Europe. Our results support the presence of at least three major clusters (Italy, Carpathians, Dinaric-Balkan) in southern and central Europe. Individuals from Croatia also appeared differentiated from wolves in Greece and Bulgaria. Expansion from glacial refugia, adaptation to local environments, and human-related factors such as landscape fragmentation and frequent killing of wolves in some areas may have contributed to the observed patterns. Our findings can help inform conservation management of these apex predators and the ecosystems of which they are part. 相似文献
192.
Wiktor Kotowski Paulina Dzierża Marek Czerwiński Łukasz Kozub Sylwia Śnieg 《Journal for Nature Conservation》2013,21(5):294-308
Drainage and shrub expansion are the main threats to the biodiversity of fens and fen meadows, whereas rewetting and the removal of shrubby species are frequently applied restoration measures. We examine whether removal of shrubs enhances recovery of target species in a degraded fen subjected to moderate rewetting. The study was located in the drained fen Ca?owanie (central Poland), where remnants of open fen communities and willow-invaded fens exist in former turf-pits, surrounded by degraded meadows on dried peat. All these three habitat types were included in a monitoring grid, which covered an area of 2.2 ha. Within 55 quadrats of 20 m × 20 m we monitored occurrence of 52 species, i.e. two groups of target species (fen indicators and wet meadow indicators) and indicators of two failure scenarios (degraded fen indicators and eutrophic wetland indicators), during six years following shrub removal, rewetting and re-application of conservational mowing, using a 3-step ordinal abundance scale. NMDS ordination revealed a gradual convergence of shrub removal plots and reference plots. We noticed significant effects of year and habitat type on all indicator groups, but only fen indicators have shown a clear (increasing) trend within shrub removal plots. Degraded fen indicators (ruderal and opportunistic species) initially expanded on shrub removal plots, but this effect disappeared in the following years. We conclude that shrub removal enhances establishment of target species in a moderately drained and then rewetted fen and attribute this effect to lowered competition for light. However, given high costs of this method and long-lasting problems with shrub resprouts, we recommend applying shrub removal only to recently overgrown sites, which still retained high botanical diversity. Heavily degraded fen meadows did not react on the increase of moisture, which indicates that more advanced restoration measures, such as top soil removal are needed there. 相似文献
193.
Iwona Hus Agnieszka Bojarska-Junak Sylwia Chocholska Waldemar Tomczak Justyna Wo? Anna Dmoszyńska Jacek Roliński 《PloS one》2013,8(11)
Th17 cells, a recently discovered subset of T helper cells that secrete IL-17A, can affect the inflammation process autoimmune and cancer diseases development. The purpose of this study was to evaluate the role of Th17 cells and IL17A in biology of CLL. The study group included 294 untreated CLL patients in different clinical stages. Here, we show that higher Th17 and IL-17A values were associated with less advanced clinical stage of CLL. Th17 cells’ percentages in PB were lower in patients who died due to CLL during follow-up due to CLL (as compared to surviving patients) and in patients responding to first-line therapy with fludarabine-based regimens (as compared to non-responders). IL-17A inversely correlated with the time from CLL diagnosis to the start of therapy and was lower in patients who required treatment during follow-up. Th-17 and IL-17A values were lower in patients with adverse prognostic factors (17p and 11q deletion, CD38 and ZAP-70 expression). CLL patients with detectable IL-17A mRNA in T cells were in Rai Stage 0 and negative for both ZAP-70 and CD38 expression. Th17 percentages positively correlated with iNKT and adversely with Treg cells. The results of this study suggest that Th17 may play a beneficial role in CLL immunity. 相似文献
194.
Natalia Lipińska Szymon Zi?tkiewicz Alicja Sobczak Agnieszka Jurczyk Wojciech Potocki Ewa Morawiec Aleksandra Wawrzycka Krzysztof Gumowski Magdalena ?lusarz Sylwia Rodziewicz-Motowid?o El?bieta Chru?ciel Krzysztof Liberek 《The Journal of biological chemistry》2013,288(4):2857-2869
Hsp100 chaperones cooperate with the Hsp70 chaperone system to disaggregate and reactivate heat-denatured aggregated proteins to promote cell survival after heat stress. The homology models of Hsp100 disaggregases suggest the presence of a conserved network of ionic interactions between the first nucleotide binding domain (NBD1) and the coiled-coil middle subdomain, the signature domain of disaggregating chaperones. Mutations intended to disrupt the putative ionic interactions in yeast Hsp104 and bacterial ClpB disaggregases resulted in remarkable changes of their biochemical properties. These included an increase in ATPase activity, a significant increase in the rate of in vitro substrate renaturation, and partial independence from the Hsp70 chaperone in disaggregation. Paradoxically, the increased activities resulted in serious growth impediments in yeast and bacterial cells instead of improvement of their thermotolerance. Our results suggest that this toxic activity is due to the ability of the mutated disaggregases to unfold independently from Hsp70, native folded proteins. Complementary changes that restore particular salt bridges within the suggested network suppressed the toxic effects. We propose a novel structural aspect of Hsp100 chaperones crucial for specificity and efficiency of the disaggregation reaction. 相似文献
195.
196.
We examined changes in profiles of isoflavonoids in roots of lupine (Lupinus luteus L. cv. Juno) seedlings in response to treatment with two heavy metals: cadmium (at 10 mg/l) and lead (at 150 mg/l). Overall, 21 flavonoid conjugates were identified in root extracts, some of them with up to six positional isomers. The total amount of all isoflavonoids increased by about 15 % in cadmium-treated plants and by 46 % in lead-treated ones. Heavy metals markedly increased the content of two compounds: 2'-hydroxygenistein glucoside and 2'-hydroxygenistein 7-O-glucoside malonylated. Possible functions of the identified isoflavonoids in yellow lupine exposed to heavy metal stress are discussed. 相似文献
197.
Bojarska-Junak A Sieklucka M Hus I Wąsik-Szczepanek E Kusz ML Surdacka A Chocholska S Dmoszyńska A Roliński J 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2011,49(1):98-103
Par-4 (prostate apoptosis response-4) protein was originally found upregulated in prostate tumor cells undergoing apoptosis. Then it was further identified as a proapoptotic protein upregulated both in normal and leukemic lymphocytes. The aim of our study was to assess PAR-4 protein expression in the B cells of CLL patients and to examine its relationship with the expression of other proteins involved in the apoptosis process, such as DAXX, ZIPK and BCL-2. We found a positive relationship between PAR-4 and BCL-2 protein expression. Additionally, there was a positive correlation between PAR-4 and both DAXX and ZIPK protein expression. The results of our research were also analyzed in association with the principal CLL prognostic factors. There was a positive correlation between the expression of PAR-4 protein and the lactate dehydrogenase (LDH) serum concentration (p < 0.005). The expression of PAR-4 protein in B cells correlated positively with the percentage of CD38(+) cells (p < 0.05), as well as with CD38(+)/ZAP-70(+) cells (p < 0.05). Moreover, we found a close relationship between LPL protein expression or LPL/ADAM29 MFI ratio and PAR-4 protein expression. Our results confirm the significance of apoptosis deregulation in CLL, and suggest a possible relationship between PAR-4 expression and the clinical course of the disease. This however requires further investigation. 相似文献
198.
Conradi J Huber S Gaus K Mertink F Royo Gracia S Strijowski U Backert S Sewald N 《Amino acids》2012,43(1):219-232
The human pathogen Helicobacter pylori that may cause different gastric diseases exploits integrins for infection of gastric cells. The H. pylori protein CagL present on the outer region of the type IV secretion pilus contains an RGD sequence (-Arg-Gly-Asp-) that enables binding to cells presenting integrins α5β1 and αVβ3. This interaction can be inhibited with conformationally designed cyclic RGD peptides derived from the CagL epitope -Ala-Leu-Arg-Gly-Asp-Leu-Ala-. The inhibition of the CagL-αVβ3 interaction by different RGD peptides strongly suggests the importance of the RGD motif for CagL binding. CagL point mutants (RAD, RGA) show decreased affinity to integrin αVβ3. Furthermore, structure-activity relationship studies with cyclic RGD peptides in a spatial screening approach show the distinct influence of the three-dimensional arrangement of RGD motif on the ability to interfere with this interaction. Resulting from these studies, similar structural requirements for the CagL epitope as previously suggested for other ligands of integrin αVβ3 are proposed. 相似文献
199.
Ditte Demontis Sylwia D. Czarnomska Petra Hájková Barbora Zemanová Josef Bryja Volker Loeschcke Cino Pertoldi 《Mammalian Biology》2011,76(5):644-645
We present 151 SNPs (single nucleotide polymorphisms) identified in Tatra and Alpine chamois individuals after genotyping with the Bovine SNP50 Genotyping BeadChip (Illumina®). Population structure analysis based on the identified 151 SNPs as well as a subset of 48 SNPs were able to give information about geographic origin of each individual making the markers suitable for future evaluation and monitoring of the genetic status of the Tatra and Alpine chamois. Our study demonstrates how it is possible to quickly identify informative SNPs in non-model organisms based on a SNP marker panel created for a related domestic species. 相似文献
200.
Krzysztof Spałek Jarosław Proćków Stanisław Staśko Sylwia Horska-Schwarz 《Central European Journal of Biology》2011,6(4):632-638
The study examines the patches of the saltwater association Ranunculetum baudotii in a new, atypical site; i.e., located more than 400 km away from the Baltic coastal line. They were found in a karst spring, and were the first locality
of the community identified in Poland. The water and sediments within the patches were analyzed chemically in the laboratory,
but, conductivity, water temperature and O2 content were measured in the field. The spring was determined to be a relatively stable aquatic habitat, with a typical chemical
composition of subterranean water (a prevalence of hydro-carbonate, calcium and magnesium ions), and rich, e.g., in nitrogen and phosphorus, and disturbed due to increasing anthropopressure. It revealed that the community analyzed favours
habitats in the zone of discharge of karst fissure waters from Jurassic, Cretaceous and Triassic water-bearing levels. In
Poland, phytocoenoses of this association, in contrast to the patches of the association in other European countries, include
no saline taxa. In Europe, Ranunculetum baudotii belongs to the group of much threatened communities and the obtained results provide the basis for its protection. 相似文献