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91.
Jakubowska-Pietkiewicz E Młynarski W Klich I Fendler W Chlebna-Sokół D 《Molecular biology reports》2012,39(5):6243-6250
To determine the relationship between the polymorphism of vitamin D receptor gene and the bone mineral density in children.
The study group consisted of 395 children aged 6–18 years. All patients underwent genotyping using the PCR-RFLP method within
polymorphic loci BsmI (rs1544410), FokI (rs2228570), ApaI (rs7975232) and Taq I (rs731236) of the VDR gene. The BMD (g/cm2, Z score) and BMC (g, Z score) by DXA method, as well as Z scores of the BUA, SOS and Stiffness ultrasound parameters were evaluated. Based on densitometry results, children were divided
into 3 groups: I—Z score ± 1.0; II—Z score from −1.1 to −2.0; and III—Z score ≤ −2.1. A control group numbering 294 children was used for the purpose of allele frequency comparisons. The occurrence
of studied polymorphism alleles in the control group did not significantly differ from the values expected according to the
Hardy–Weinberg equilibrium (p values: 0.1224 for BsmI; 0.5958 for TaqI; 0.0817 for ApaI; and 0.8901 for FokI). Allele a ApaI carrier status in group III children was associated with an increased BMD (x = 0.8 vs 0.69, p = 0.0296) and BMC value (x = 28.76 vs 22.14, p = 0.0565) in spine projection results, Stiffness (x = −1.12 vs −1.91, p = 0.0347) and SOS (x = −1.43 vs −2.27, p = 0.0319) ultrasound parameters. In group II, significantly increased SOS values (−1.13 vs −1.73, p = 0.0378) were noted in f (FokI) carriers. The presence of aa
ApaI and ff
FokI polymorphisms favours a higher bone mass and better bone structure (decreased bone mass loss) in the analysed group. 相似文献
92.
Dariusz Pańka Dariusz PiesikMałgorzata Jeske Anna Baturo-Cieśniewska 《Journal of plant physiology》2013
Grasses very often form symbiotic associations with Neotyphodium/Epichloë endophytic fungi. These endophytes often allow the host grass to be protected from different pathogens. However, there is little known about the mechanisms of such endophyte influence on the host. Thus, the purpose of this research was to examine the effect of the N. lolii endophyte on the total production of phenolic compounds, VOCs emission and the resistance of three perennial ryegrass genotypes infected by pathogenic Fusarium poae. Analyses of total phenolics content were performed in control (not inoculated) and inoculated plants after 1, 2, 3, 4, 5, and 6 days (DAI) and for VOCs after 0, 3, 6 and 12 DAI. The presence of endophytes significantly reduced the disease index in two of the three genotypes relative to that in E−. Plants infected by N. lolii exhibited higher production of phenolics relative to the E− plants. The highest amounts of phenolics were observed on the second and sixth DAI. Genotype Nl22 showed the strongest effect of the endophyte on the production of phenolics, which increased by over 61%. Both the endophyte infected and non-infected plants emitted most abundantly two GLVs ((Z)-3-hexenal, (Z)-3-hexen-1-yl acetate), three terpenes (linalool, (Z)-ocimene, β-caryophyllene) and three shikimic acid pathway derivatives (benzyl acetate, indole, and methyl salicylate). The endophyte presence and the intervals of VOCs detection were a highly significant source of variation for all emitted volatiles (P < 0.001). The genotype of the perennial ryegrass significantly affected only the emission of methyl salicylate (P < 0.05) and β-caryophyllene (P < 0.05). Most of the VOCs ((Z)-3-hexen-1-yl acetate, (Z)-3-hexenal, linalool and methyl salicylate) reached their highest levels of emission on the sixth DAI, when averaged over genotypes and endophyte status. The results highlight the role of Neotyphodium spp. in the mediation of quadro-trophic interactions among plants, symbiotic endophytes, invertebrate herbivores and plant pathogenic fungi. Our results also confirm the fact that symbiotic plants can activate a defense reaction faster than non-symbiotic plants after a pathogen attack. Thus, N. lolii can be involved in the defense of perennial ryegrass against pathogens and potentially could be central to the host plants’ protection. 相似文献
93.
Tomasz Wesołowski 《Bird Study》2013,60(3):199-204
Capsule Re-use is infrequent although birds reproduce equally well in re-used and new holes. Aims To describe frequency of hole re-use by Marsh Tits in primeval forest with superabundant holes; to examine how depredation, disturbance, ectoparasites or the low quality of previously used holes influenced birds' decision to switch holes; to assess whether Marsh Tits benefited from re-using holes. Methods Birds were observed living in undisturbed conditions in a strictly protected part of the Bia?owie?a National Park (Poland) during 13 breeding seasons, hole attributes were measured, and observations made of nest fate and bird survival. Results Marsh Tits re-occupied 35.5% of available holes used the previous year (n = 214). The holes were most often re-used when both birds survived (42%) or when the surviving female was paired to a new male (35%). Holes were re-used less often after brood failure than after successful breeding (13% versus 39%). Other possible factors (ectoparasite infestation, inferior hole quality or a bird being caught at hole) had no effect on the re-occupation frequency. Birds in the retained and new holes bred at the same time, laid the same number of eggs, and had almost identical nesting success (78% versus 76%). Conclusion Superabundant holes in the primeval forest allow Marsh Tits to change holes frequently. Similar outcomes of breeding in the re-used and new holes indicate that choices made by the birds are largely neutral, i.e. there is no strong selection pressure for or against hole re-use. 相似文献
94.
95.
Summary During cell division in antheridial filaments ofChara vulgaris an increase in DNA content occurs in both shield cells and manubria within an antheridium, reaching 16C–64C and 8C–32C levels, respectively. Endoreplication ceases prior to the formation of spermatids and initiation of spermiogenesis, probably as a result of symplasmic isolation of the antheridium from the thallus. As the DNA content of the nuclei increases, the shield cells3H-leucine incorporation increases, and they grow intensively in the tangential plane. Translation decreases considerably after termination of shield cell growth. DNA content of mature manubria is half of that in shield cells, although their size is 10 times that of manubria. Translational activity of manubria also increases as DNA content rises and cells grow. However, during spermiogenesis, this activity remains at its maximum, which is associated with the secretory function of the manubria. Spermiogenesis is also accompanied by far-reaching ultrastructural changes within the manubrial cytoplasm.The level of endopolyploidy in both shield cells and manubria of antheridia formed in the spring is higher by one replication cycle, than in autumnal antheridia. AMO-1618, at a concentration of 10–5M reduces the DNA content in the autumnal manubria. The higher the manubrial level of endopolyploidy in spermiogenesis, the greater their size, and the higher the translational activity and number of joined spermatids. The number of spermatozoids in the antheridium is also positively correlated with the internal volume of an antheridium, which is itself dependent on the endopolyploidy level of shield cells.The results obtained confirm the assumption that endoreplication favours the higher growth dynamics and potential translational activity, which occurs in the dynamic growth phase only in shield cells, while in manubria, i.e. cells producing substances necessary to spermatozoids development, it remains high until the end of spermiogenesis. 相似文献
96.
Kremser ME Przybyło M Hoja-Łukowicz D Pocheć E Amoresano A Carpentieri A Bubka M Lityńska A 《Biochimica et biophysica acta》2008,1780(12):1421-1431
It is well documented that glycan synthesis is altered in some pathological processes, including cancer. The most frequently observed alterations during tumourigenesis are extensive expression of beta1,6-branched complex type N-glycans, the presence of poly-N-acetyllactosamine structures, and high sialylation of cell surface glycoproteins. This study investigated two integrins, alpha3beta1 and alpha(v)beta3, whose expression is closely related to cancer progression. Their oligosaccharide structures in two metastatic melanoma cell lines (WM9, WM239) were analysed with the use of matrix-assisted laser desorption ionisation mass spectrometry. Both examined integrins possessed heavily sialylated and fucosylated glycans, with beta1,6-branches and short polylactosamine chains. In WM9 cells, alpha3beta1 integrin was more variously glycosylated than alpha(v)beta3; in WM239 cells the situation was the reverse. Functional studies (wound healing and ELISA integrin binding assays) revealed that the N-oligosaccharide component of the tested integrins influenced melanoma cell migration on vitronectin and alpha3beta1 integrin binding to laminin-5. Additionally, more variously glycosylated integrins exerted a stronger influence on these parameters. To the best of our knowledge, this is the first report concerning structural characterisation of alpha(v)beta3 integrin glycans in melanoma or in any cancer cells. 相似文献
97.
98.
Effect of age,size and digestive tract development on weaning effectiveness in crucian carp,Carassius carassius (Linnaeus, 1758) 下载免费PDF全文
B. Łączyńska K. Palińska‐Żarska J. Nowosad M. Biłas S. Krejszeff T. Müller D. Kucharczyk D. Żarski 《Zeitschrift fur angewandte Ichthyologie》2016,32(5):866-872
The study aim was to determine the optimum age, wet body weight (WBW) and total length (TL) of the crucian carp, Carassius carassius (L.), to ensure the effectiveness of weaning directly without a gradual transfer from live food to a compound feed. Moreover, the state of development of the digestive tract was analyzed histologically based on the height of enterocytes. Experimental rearing was conducted between days 5 and 45 post hatch (DPH). Initial WBW of fish was 2.2 ± 0.6 (n = 30) mg and TL 6.1 ± 0.1 (n = 30) mm. Rearing was carried out at 27 ± 0.5°C, with fish divided into six groups: one control (C) fed with Artemia sp. nauplii, and five groups initially fed with Artemia sp. but later replaced by a compound feed. Weaning with the compound diet started at 15, 20, 25, 30 and 35 DPH in groups labeled F15, F20, F25, F30, F35, respectively. Larvae were fed three times per day (08.00 h, 13.00 h, 18.00 h) in equal portions (4% of larvae biomass per day, converted to the dry matter of the feed). Daily biomass growth was adopted as 15%. Each group was triplicated (n = 50 individuals per replicate). Highest values of TL 42.1 ± 0.7 (n = 30) mm and WBW 905.3 ± 50.3 (n = 30) mg were recorded in the control group at 45 DPH; lowest survival rate of 45 DPH was in group F15 (90.7 ± 1.2%, n = 30). The highest value of the enterocyte epithelial length was observed in individuals within groups F30, 34.8 ± 1.2 μm (n = 30) and F35, 35.4 ± 3.6 μm (n = 30), respectively, 30 and 35 DPH; highest percentage of deformations on the final day of the experiment was in group F15 (100 ± 0.0%, n = 30). The results indicate that an effective direct transfer from live food to prepared diets (with no gradual transfer) cannot be performed with crucian carp larvae before 30 DPH at 27°C, when the fish have reached TL = 31.1 ± 0.4 mm (n = 30) and WBW = 436.9 ± 13.7 mg (n = 30). 相似文献
99.
Recent changes in environmental conditions in populations of peat-bog pine (Pinus uliginosa Neumann) caused rapid decline or even extinction of the species in several stands in Central Europe. Conservation strategies
forP. uliginosa require information about the evolutionary history and genetic structure of its populations. Using isozymes we assessed the
genetic structure ofP. uliginosa from four isolated stands in Poland and compared the results to genetic structures of other closely related pine species
including eight populations ofPinus mugo, ten ofPinus sylvestris and one ofPinus uncinata. The level of genetic variability ofP. uliginosa measured by the mean number of alleles per locus and average heterozygosity was similar to others related toP. uliginosa taxa from the reference group but it differs among populations. High genetic similarity was found between two populations
ofP. uliginosa from Low Silesian Pinewood. The populations were genetically distinct as compared to other populations includinglocus classicus of the species from the peat bog at Batorów Reserve. Very low genetic distance (Dn = 0.002) and small genetic differentiation (GST = 0.003) were found betweenP. uliginosa andP. mugo in the sympatric populations of the species from Zieleniec peat bog suggesting the ongoing natural hybridisation and genetic
contamination of peat-bog pine from this area. Some evidence for skew in allele frequency distribution potentially due to
recent bottleneck was found in population from Low Silesian Pinewood. The analysed open pollinated progeny derived from twoP. uliginosa stands from Low Silesian Pine-wood showed the excess of homozygotes as compared to the maternal trees indicating high level
of inbreeding (F = 0.105,F = 0.081). The results are discussed in the context of evolution ofP. uliginosa populations, taxonomic relationships between the analysed species and conservation strategies for active protection of peat-bog
pine. 相似文献
100.
Daniel Kubisz Łukasz Kajtoch Miłosz A. Mazur Agata Lis Milada Holecová 《Invertebrate Biology》2012,131(4):333-344
Xerothermic species are rare and threatened in central and eastern Europe. In light of the continuing loss of steppe‐like habitats due to anthropogenic fragmentation and degradation, the evaluation of genetic variation in populations inhabiting them is of immediate importance if appropriate conservation measures are to be undertaken. Here we report on the genetic diversity of the rare leaf beetle Crioceris quatuordecimpunctata, whose populations in central and eastern Europe inhabit highly geographically isolated areas. All of the studied populations (in Poland, Ukraine, and Slovakia) were differentiated at the mitochondrial marker COI. However, with respect to the nuclear marker ITS1, Polish populations were monomorphic, but distinct from all other populations. The distinctiveness of the studied populations was confirmed by Wolbachia screening, which showed that all populations carried different strains (one or two), which were probably transferred independently from other insects. On the other hand, no diversity was found in any marker within particular populations, which could be caused (at least for mtDNA) by a Wolbachia selective sweep. Crioceris quatuordecimpunctata probably consists of isolated populations, which went through narrow bottlenecks leading to a drastic reduction in their genetic diversity. As these populations are reciprocally monophyletic for mtDNA haplotypes and show a significant divergence of allele frequencies at nuclear loci, they could be classified as evolutionarily significant units (ESUs). In addition, DNA barcodes were used to identify Asparagus officinalis as the host plant for members of all studied populations. These data should be valuable in efforts to conserve populations of C. quatuordecimpunctata (e.g., for guiding reintroductions). 相似文献