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61.
Katarzyna Bzdęga Agnieszka Janiak Sabina Tarłowska Marzena Kurowska Barbara Tokarska-Guzik Iwona Szarejko 《Flora》2012
Recently much attention has been paid to genetic aspects of invasive success in Japanese knotweed s.l. One hypothesis to explain the invasive spread of these species is a multiple introduction, which leads to a higher level of genetic diversity in the invaded range. Fallopia japonica is considered to be genetically uniform in Europe, introduced as a single female clone. However, there is some evidence suggesting that invasion history and dynamics differ between Western and Central-Eastern Europe. We used AFLP markers to characterize genetic diversity of three Fallopia taxa that occur in Poland: F. japonica, F. sachalinensis and their hybrid Fallopia × bohemica, growing in so-called ‘homogeneous’ populations, consisting of one taxon and ‘heterogeneous’ populations, composed of the three taxa cohabiting together. No polymorphism, resp. an insignificantly low variability was observed in the ‘homogeneous’ populations. In the ‘heterogeneous’ stands polymorphism was detected within each taxa, with one exception that concerns individuals of F. sachalinensis from a riparian habitat. The highest level of polymorphism was found among individuals of F. × bohemica. The most striking result of our study is the observation of polymorphism between individuals of F. japonica. The AFLP data also showed that F. × bohemica is most diverse when occurring in a heterogeneous configuration with F. japonica and F. sachalinensis in the same habitat. Our results are the first evidence of genetic diversity in F. japonica populations in Central Europe and can implicate the possibility of its multiple introduction in this region or the existence of sexual reproduction of this species. 相似文献
62.
Rita Brines Nuria Maicas María Luisa Ferrándiz Agnieszka Loboda Alicja Jozkowicz Jozef Dulak María José Alcaraz 《PloS one》2012,7(12)
Background
Heme oxygenase-1 (HO-1) is induced in many cell types as a defense mechanism against stress. We have investigated the possible role of endogenous HO-1 in the effector phase of arthritis using the K/BxN serum transfer model of arthritis in HO-1 heterozygous and homozygous knock-out mice.Methodology/Principal Findings
Arthritis was induced in C57/Black-6 xFVB (HO-1+/+, HO-1+/− and HO-1−/−) mice by intraperitoneal injection of 150 µl serum from arthritic K/BxN mice at days 0 and 2. Blood was collected and animals were sacrificed at day 10. Histological analysis was performed in ankle sections. The levels of inflammatory mediators were measured in serum and paw homogenates by enzyme-linked immunosorbent assay or Multiplex technology. The incidence of arthritis was higher in HO-1+/− and HO-1−/− groups compared with HO-1+/+. The inflammatory response was aggravated in HO-1+/− mice as shown by arthritic score and the migration of inflammatory cells that could be related to the enhancement of CXCL-1 production. In addition, the HO-1+/− group showed proteoglycan depletion significantly higher than HO-1+/+ mice. Serum levels of matrix metalloproteinase-3, monocyte chemotactic protein-1, plasminogen activator inhibitor-1, E-selectin and intercellular adhesion molecule-1 were increased in arthritic HO-1−/− mice, whereas vascular endothelial growth factor and some cytokines such as interferon-γ showed a reduction compared to HO-1+/+ or HO-1+/− mice. In addition, down-regulated gene expression of ferritin, glutathione S-reductase A1 and superoxide dismutase-2 was observed in the livers of arthritic HO-1+/− animals.Conclusion/Significance
Endogenous HO-1 regulates the production of systemic and local inflammatory mediators and plays a protective role in K/BxN serum transfer arthritis. 相似文献63.
Vasanthi R Sunil Agnieszka J Connor Peihong Zhou Marion K Gordon Jeffrey D Laskin Debra L Laskin 《Respiratory research》2002,3(1):21
Background
Neutrophils constitute the first line of defense against invading microorganisms. Whereas these cells readily undergo apoptosis under homeostatic conditions, their survival is prolonged during inflammatory reactions and they become biochemically and functionally activated. In the present study, we analyzed the effects of acute endotoxemia on the response of a unique subpopulation of neutrophils tightly adhered to the lung vasculature. 相似文献64.
Gütschow M Kuerschner L Pietsch M Ambrozak A Neumann U Günther R Hofmann HJ 《Archives of biochemistry and biophysics》2002,402(2):180-191
A series of benzoxazinones was used to investigate the interaction of human cathepsin G with acyl-enzyme inhibitors. With respect to the primary specificity of cathepsin G, inhibitors with hydrophobic or basic residues at position 2 were included in the study. Parameters of the enzyme acylation and deacylation were determined by slow-binding kinetics in the presence of a chromogenic substrate. For selected inhibitors, the time course of the enzyme-catalyzed conversion of the inhibitors was followed. This approach was suitable to elucidate a rate-determining deacylation step. Docking simulations of the noncovalent enzyme-inhibitor complexes were performed and several clusters were analyzed for each inhibitor. The amino acids of the active site that participate in the binding of the inhibitors were determined. The arrangements in several clusters of an inhibitor were not uniform with respect to the orientation by which the inhibitor was bound in the S(1) pocket. Docking of the basic piperazino derivatives 6 and 10 indicated an interaction with Glu 226 at the bottom of the S(1) specificity pocket. The (N-methyl)benzylamino derivative 1 showed the strongest acylation rate (k(on)=1200 M(-1) s(-1)), which was attributed to a high extent of pseudo-productive orientations of the noncovalent preassociation complex. 相似文献
65.
Kazimierczuk Z Upcroft JA Upcroft P Górska A Starościak B Laudy A 《Acta biochimica Polonica》2002,49(1):185-195
Two series of benzimidazole derivatives were sythesised. The first one was based on 5,6-dinitrobenzimidazole, the second one comprises 2-thioalkyl- and thioaryl-substituted modified benzimidazoles. Antibacterial and antiprotozoal activity of the newly obtained compounds was studied. Some thioalkyl derivatives showed remarkable activity against nosocomial strains of Stenotrophomonas malthophilia, and an activity comparable to that of metronidazole against gram-positive and gram-negative bacteria. Of the tested compounds, 5,6-dichloro-2-(4-nitrobenzylthio)-benzimidazole showed the most distinct antiprotozoal activity. 相似文献
66.
Agnieszka Tomza-Marciniak Bogumi?a Pilarczyk Ma?gorzata B?kowska Marek Ligocki Marcelina Gaik 《Biological trace element research》2012,149(3):345-351
This study was designed to evaluate the degree of exposure of pet dogs from an urban area of NW Poland to selected metals, including toxic Cd and Pb. The study was conducted on a group of 48 healthy dogs. The serum concentration of the analysed elements followed the order Fe > Al > Zn > Cu > Mn > As > Sr > Pb > Cd > Cr > Ni > V. The presence of cadmium and lead was found in all the serum samples tested. The average contents of these elements were 0.309 and 0.489???g/mL. The factors that played the greatest role in the intake of the analysed elements were diet and breed-dependent size of dogs. Small-sized dogs had higher concentrations of all elements compared with large dogs, with statistically significant differences noted for Cu, Pb, Cd and Sr. It was also found that dogs receiving commercial and mixed food had more metals in serum compared with dogs on homemade food (except strontium). The present study showed elevated concentrations of some heavy metals (Pb, Cd, Fe and Cu) in serum of pet dogs, which is probably due to the excess elemental load of this area. Given that no information is available on the concentrations of strontium, vanadium and aluminium in dogs, further research is necessary to determine certain reference values which would allow for an easier interpretation of results and evaluation of exposure to these elements. 相似文献
67.
Profiling of gene expression in bacteria is now being used to uncover unknown genes expressed in particular genetic backgrounds or environmental conditions. Obtaining the best possible information from the expected avalanche of such experiments will require standardization of both experimental approach and statistical analysis. The first such experiments reveal challenges, pitfalls and reasonable solutions. 相似文献
68.
Anna Filipek Agnieszka Zasada Urszula Wojda Robert Makuch Renata Dbrowska 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》1996,113(4):745-752
Using a procedure developed to purify calcyclin from mouse Ehrlich ascites tumor cells calcyclin was purified from smooth muscle of chicken gizzard. Chicken gizzard calcyclin bound to phenyl-Sepharose in a calcium dependent manner as did mouse EAT cells and rabbit lung calcyclin but appeared to be more acidic than its mammalian counterparts as revealed by ion exchange chromatography on Mono Q. Chicken gizzard calcyclin bound 45Ca2+ on nitrocellulose filters and exhibited a shift in electrophoretic mobility on urea-PAGE depending on Ca2+ concentration. Crosslinking experiments with BS3 showed that chicken gizzard calcyclin was able to form noncovalent dimers. As indicated by a decrease in maximum tryptophan fluorescence emission of caldesmon (about 14% at 1:1 molar ratio) and displacement of calmodulin from its complex with caldesmon, chicken gizzard calcyclin binds caldesmon. This binding was, however, much weaker than that of calmodulin and could not influence the interaction of caldesmon with actin. In consequence, calcyclin was unable to reverse the inhibitory effect of caldesmon on actin-activated Mg2+-ATPase activity of myosin in the presence of Ca2+. 相似文献
69.
Eleven strains of Escherichia coli were isolated from 54 bank voles living in the LomZa Landscape Park of the Narew River Valley, indicating that E. coli is not common in the alimentary tract of these mammals. On the basis of pulsed-field gel electrophoresis and computer-assisted analysis, the isolates were grouped into six genotypes at similarities of 39%. Chromosome length of E. coli under study differed by as much as 900 kb, ranging 2.7-3.6 Mb. All strains were susceptible to amikacin and ciprofloxacin, whereas, for tetracycline, streptomycin, ampicillin, and cefonicid, different results were noted. No differences were detected among the plasmid complements of eight strains (73%), for which plasmid profiles revealed the presence of two plasmidic bands. One, three and four plasmids were observed in a plasmid pattern of single isolates. The observation from the study indicated the high genetic polymorphism among the isolates recovered from the animals of one species living in the same environment. 相似文献
70.
Subspecific relationships of the European beaverCastor fiber have been obscured by failure to follow the rules of the International Code of Zoological Nomenclature and remain an open
issue. Inconsequence in the use of subspecies names caused a nomenclatural as well as a taxonomic confusion. We discuss these
controversial and incorrect nomenclatural decisions, and recognize 9 nominal subspecies of European beaver, bearing 9 available
names:C. f. fiber Linnaeus, 1758,C. f. galliae Geoffroy, 1803, C. f. albicus Matschie, 1907,C. f. vistulanus Matschie, 1907,C. f. pohlei Serebrennikov, 1929,C. f. birulai Serebrennikov, 1929,C. f. tuvinicus Lavrov, 1969,C. f. belorussicus Lavrov, 1981, andC. f. orientoeuropaeus Lavrov, 1981. 相似文献