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71.
Wojciech Szewczyk Hanna Kwaśna Jolanta Behnke-Borowczyk Marlena Baranowska-Wasilewska 《Central European Journal of Biology》2014,9(6):614-627
Porodaedalea pini has been found to be a pathogen of Pinus banksiana (1 specimen) and Pinus sylvestris (39 specimens) in north-western Poland. This fungus was initially identified by its host preferences and morphological characters of sporophores and basidiospores. The ITS 1/2 rDNA region was sequenced and analysed using the neighbor-joining, maximum likelihood and maximum parsimony methods. All P. pini from Poland, P. pini neotype and other P. pini isolates from Europe grouped together forming a moderately supported monophyletic clade. The clade included two groups which did not correlate with geographic ranges. Nucleotide polymorphism of the Polish isolates of P. pini was small. This study provides evidence for the taxonomy of some isolates of the Porodaedalea Holarctic Group in North America: grouping with P. laricis or with P. gilbertsonii suggests that the isolates belong to these species. The absence of P. pini (in a form recognized in Europe) in North America is suggested. Sequencing of the ITS 1/2 rDNA region with the basidiomycete-specific primers (ITS1-F and ITS4-B) proved to be a suitable and sufficient method for differentiation of species within the genus Porodaedalea. 相似文献
72.
Tanifuji G Kim E Onodera NT Gibeault R Dlutek M Cawthorn RJ Fiala I Lukes J Greenwood SJ Archibald JM 《Eukaryotic cell》2011,10(8):1143-1146
We have performed a genomic characterization of a kinetoplastid protist living within the amoebozoan Neoparamoeba pemaquidensis. The genome of this "Ichthyobodo-related organism" was found to be unexpectedly large, with at least 11 chromosomes between 1.0 and 3.5 Mbp and a total genome size of at least 25 Mbp. 相似文献
73.
Marcin Czarnoleski Katarzyna Pawlik Pawe? Olejniczak Jan Koz?owski Marlena Lembicz 《Plant Ecology》2012,213(6):1049-1053
The interactions of endophytes with plants are believed to evolve over time from parasitic to mutualistic, and in the seed-transmitted fungal endophytes, these interactions are conventionally treated as mutualistic. The weeping alkaligrass Puccinellia distans has recently dispersed to new habitats in Europe, where it was colonised by the seed-transmitted fungus Epichlo? typhina. The E. typhina-infected weeping alkaligrass has a fertility advantage over -uninfected plants, but this advantage is held only over shorter time scales. We assess the antiherbivore value of E. typhina in mature weeping alkaligrass against common voles Microtus arvalis, a herbivore naturally co-occurring with weeping alkaligrass. In two consecutive food-choice tests conducted in a lab, we examined feeding by na?ve voles on E. typhina-infected (E+) and -uninfected grass (E?) originating from Central Europe. In the first test, all voles consumed comparable amounts of E+ biomass and E? biomass. In the subsequent test, the voles reduced their feeding rates by 57?%, but E+ food was avoided twice as frequently as E? food (75 vs. 33?% reduction). This result suggests that toxins produced by E. typhina repel herbivores soon after the first contact. We show that in addition to its direct fitness consequences, endophyte-mediated resistance to herbivory increases the fertility advantage of E. typhina-infected weeping alkaligrass. This effect can increase the ability of weeping alkaligrass to invade habitats with intense herbivory. 相似文献
74.
Overt autoantibodies to the smaller isoform of glutamate decarboxylase (GAD65Ab) are a characteristic in patients with Type 1 diabetes (T1D). Anti-idiotypic antibodies (anti-Id) directed to GAD65Ab effectively prevent the binding of GAD65 to GAD65Ab in healthy individuals. Levels of GAD65Ab-specific anti-Id are significantly lower in patients with T1D, leading to overt GAD65Ab in these patients. To determine the possible protective role of GAD65Ab-specific anti-Id in T1D pathogenesis, we developed the monoclonal anti-Id MAb 8E6G4 specifically targeting human monoclonal GAD65Ab b96.11. MAb 8E6G4 was demonstrated as a specific anti-Id directed to the antigen binding site of b96.11. MAb 8E6G4 recognized human antibodies in sera from healthy individuals, T2D patients, and T1D patients as established by ELISA. We confirmed these MAb 8E6G4-bound human antibodies to contain GAD65Ab by testing the eluted antibodies for binding to GAD65 in radioligand binding assays. These findings confirm that GAD65Ab are present in sera of individuals, who test GAD65Ab-negative in conventional detection assays. To test our hypothesis that GAD65Ab-specific anti-Id have an immune modulatory role in T1D, we injected young Non Obese Diabetic (NOD) mice with MAb 8E6G4. The animals were carefully monitored for development of T1D for 40 weeks. Infiltration of pancreatic islets by mononuclear cells (insulitis) was determined to establish the extent of an autoimmune attack on the pancreatic islets. Administration of MAb 8E6G4 significantly reduced the cumulative incidence rate of T1D and delayed the time of onset. Insulitis was significantly less severe in animals that received MAb 8E6G4 as compared to control animals. These results support our hypothesis that anti-Id specific to GAD65Ab have a protective role in T1D. 相似文献
75.
Zeyland J Wolko L Lipiński D Woźniak A Nowak A Szalata M Bocianowski J Słomski R 《Journal of applied genetics》2012,53(3):317-322
One of the most informative sources which allow the drawing of far-reaching conclusions about the origins and phylogenetics of many species, including domestic animals and humans, is mitochondrial DNA (mtDNA). One of the important research targets should include the identification of similarities between wild and domestic species. The analysis involved the nucleotide sequences of mtDNA of wisent, auroch, bison, yak, bovine reference sequence (BRS) T3, T3a, T3b, T1, T1a, T1'2'3, T2, T3, T4, T5, Q, Q1, P, R, I1, and I2 bovine haplotypes. The non-coding D-loop regions were excluded from the evolutionary analysis and 15,419-bp coding sequences were used in the final dataset. Trees constructed on the basis of whole mitochondrial genomes or on total mtDNA coding sequences alignment were generally in agreement with previous studies on the Bovini tribe. American bison shows stronger maternal relationships to yak than to wisent. It seems that the isolation and divergence of wisent took place early, almost 2 to 1.6 million years ago. This appears to be compatible with the paleontological date, indicating Late Pleistocene speciation of Bison bonasus. The yak/bison mitochondrial transfer model is in agreement with our mutation analysis and phylogenetic tree. The bison/yak mutations were collected in the bison mitochondrial genome before the transfer. After the transfer, the parallel accumulation of unique mutations took place. According to our assessment, the transfer took place at about 700 ky. The characteristic feature of the wisent and bison evolution is the maintenance of mtDNA variability, despite the fact that both species underwent population bottlenecks. Our studies did not reveal any impact of these phenomena populations in the analyzed mitochondrial genomes. 相似文献
76.
Agnieszka M. Bogdanowicz Paweł Olejniczak Marlena Lembicz Waldemar Żukowski 《Central European Journal of Biology》2011,6(5):870-877
We tested a hypothesis based on life history theory that examines reproductive costs incurred by individuals in consecutive
years of their life. A multi-year dataset of resource allocation to vegetative and reproductive structures was analysed in
Carex secalina — a perennial, monoecious sedge, reproducing only sexually. In a four-year garden experiment, we assessed above-ground biomass
at the end of each season and reproductive allocation expressed as the total length of male and female spikes. The study was
aimed at determining how size and age of a plant relates to its reproduction, and how the rate of reproduction affects the
year-toyear biomass change in Carex secalina. We observed that after each reproductive episode, individuals had significantly smaller sizes and produced a lower number
of generative tillers. The total production of reproductive structures decreased significantly with age in all populations.
Moreover, the decrease in plant biomass was greater when more reproductive structures were produced in a previous year, which
indicates that the plants incur costs of reproduction in terms of above-ground biomass production. 相似文献
77.
Genetic Diversity and Horizontal Transfer of Genes Involved in Oxidation of Reduced Phosphorus Compounds by Alcaligenes faecalis WM2072
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Enrichment was performed to isolate organisms that could utilize reduced phosphorus compounds as their sole phosphorus sources. One isolate that grew well with either hypophosphite or phosphite was identified by 16S rRNA gene analysis as a strain of Alcaligenes faecalis. The genes required for oxidation of hypophosphite and phosphite by this organism were identified by using transposon mutagenesis and include homologs of the ptxD and htxA genes of Pseudomonas stutzeri WM88, which encode an NAD-dependent phosphite dehydrogenase (PtxD) and 2-oxoglutarate-dependent hypophosphite dioxygenase (HtxA). This organism also has the htxB, htxC, and htxD genes that comprise an ABC-type transporter, presumably for hypophosphite and phosphite transport. The role of these genes in reduced phosphorus metabolism was confirmed by analyzing the growth of mutants in which these genes were deleted. Sequencing data showed that htxA, htxB, htxC, and htxD are virtually identical to their homologs in P. stutzeri at the DNA level, indicating that horizontal gene transfer occurred. However, A. faecalis ptxD is very different from its P. stutzeri homolog and represents a new ptxD lineage. Therefore, this gene has ancient evolutionary roots in bacteria. These data suggest that there is strong evolutionary selection for the ability of microorganisms to oxidize hypophosphite and phosphite. 相似文献
78.
Marzena Wyganowska-Swiatkowska Paulina Urbaniak Daniel Lipinski Marlena Szalata Malgorzata Kotwicka 《Human cell》2017,30(3):181-191
Enamel matrix derivative (EMD) containing a variety of protein fractions has been used for periodontal tissue regeneration. It is suggested that the proteins contained in EMD positively influence gingival fibroblasts migration and proliferation. Effects of EMD as well as of porcine recombinated 21.3-kDa amelogenin (prAMEL) and 5.3-kDa tyrosine-rich amelogenin peptide (prTRAP) on human gingival fibroblast (HGF-1, ATCC; USA) cell line were investigated. Real-time cell analysis (xCELLigence system; Roche Applied Science) was performed to determine the effects of EMD, prAMEL and prTRAP (12.5–50 μg/mL) on HGF-1 cell proliferation and migration. The effect of treatment on cell cycle was determined using flow cytometry. EMD significantly increased HGF-1 cell proliferation after 24- and 48-h incubation. Individually, prAMEL and prTRAP also increased HGF-1 cell proliferation; however, the difference was significant only for prAMEL 50 µg/mL. prAMEL and TRAP significantly increased HGF-1 cell migration after 60- and 72-h incubation. Cell cycle analysis showed significant decrease of the percentage of cells in the G0/G1 phase and a buildup of cells in the S and M phase observed after EMD and prAMEL stimulation. This process was ligand and concentration-dependent. The various molecular components in the enamel matrix derivative might contribute to the reported effects on gingival tissue regeneration; however, biologic effects of prAMEL and prTRAP individually were different from that of EMD. 相似文献
79.
Link JT Sorensen BK Lai C Wang J Fung S Deng D Emery M Carroll S Grynfarb M Goos-Nilsson A Von Geldern T 《Bioorganic & medicinal chemistry letters》2004,14(16):4173-4178
The synthesis, activity, metabolic stability, and pharmacokinetics of steroidal and nonsteroidal glucocorticoid receptor modulator-statin hybrids is reported. Potent steroidal antagonist-statin hybrids like 22 (h-GR binding IC(50)=7 nM) and nonsteroidal modulator hybrids like 16 (h-GR binding IC(50)=2 nM) were discovered. Appending a 'statin'-like diol-acid group to the modulators dramatically improved metabolic stability (and in some cases hepatocyte activity), but did not impart hepatoselectivity. 相似文献
80.
Link JT Sorensen BK Patel J Emery M Grynfarb M Goos-Nilsson A 《Bioorganic & medicinal chemistry letters》2004,14(9):2209-2212
A new class of selective nonsteroidal glucocorticoid receptor modulators typified by N-[3-[benzyl-(4-chloro-2-fluoro-benzyl)-amino]-2-methyl-phenyl]-methanesulfonamide 19 has been discovered. 相似文献