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71.
Ewa Kosior-Jarecka Urszula ?ukasik Dominika Wróbel-Dudzińska Janusz Kocki Joanna Bartosińska Agnieszka Witczak Gra?yna Chodorowska Jerzy Mosiewicz Tomasz ?arnowski 《PloS one》2016,11(1)
Aim
The purpose of this study was to evaluate the influence of polymorphisms of the eNOS gene on the clinical status of patients with normal and high tension glaucoma.Methods
266 Polish Caucasian patients with primary open angle glaucoma were studied. Of the 266, 156 had normal tension glaucoma (NTG) and 110 high tension glaucoma (HTG). DNA material was isolated from peripheral venous blood using commercial kits. Real-time PCR reaction was used to amplify the promoter site of the endothelial nitric oxide synthase (eNOS) gene, including the single nucleotide polymorphism (SNP) site T-786C and part of the 7th exon of eNOS, including G894T SNP. Genotypes were determined with TaqMan SNP Genotyping Assays.Results
There were no significant differences in frequencies of the allelic variants of both polymorphisms. In G894T SNP, however, the wild GG form was more common in the HTG group. The SNP of the eNOS gene did not significantly influence the progression rate in either of the groups studied. There were no differences in variants of the eNOS gene regarding the necessity for and success of surgery and the progression of the disease. In the NTG group, no statistical correlation was observed between G894T, T786C polymorphism variants, and risk factors such as optic disc haemorrhages, optic disc notches, and peripapillary atrophy. Mean diastolic and systolic pressure during the day and night were lowest in NTG patients with the CC variant of the T786C polymorphism. No statistical correlation was observed between the G894T and T786C polymorphisms and capillaroscopic examination results.Conclusions
Genotype frequencies are similar for both the eNOS G894T and T-786C polymorphisms in NTG and HTG patients. These polymorphisms do not correlate with risk factors and do not influence the state of the capillary system in NTG patients. Systolic blood pressure is lower in NTG patients with mutated alleles of both polymorphisms. 相似文献72.
Disentangling Relations among Repertoire Size,Song Rate,Signal Redundancy and Ambient Noise Level in European Songbird
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Krzysztof Deoniziak Tomasz S. Osiejuk 《Ethology : formerly Zeitschrift fur Tierpsychologie》2016,122(9):734-744
The majority of male songbirds have small repertoires and sing with eventual variety; that is, they present one song type several times before switching to the next one. Several hypotheses have been proposed to explain this phenomenon. The antiexhaustion hypothesis argues that song‐type switching prevents muscle fatigue in the syrinx. The signal redundancy hypothesis suggests that repeating the same signal increases transmission success. Here, we have studied the song behaviour of the chaffinch, Fringilla coelebs, a common Eurasian species in which the males sing a few different song types and provide eventual variety. We tested different hypotheses to explain the temporal organisation of song output (repertoire size, song rate, bout duration, etc.) as a function of ambient noise by comparing birds from the same macrogeographic region in which the birds live either in a noisy town (n = 71) or in a quieter forest habitat (n = 68). Contrary to the prediction of the signal redundancy hypothesis and the results of earlier work on chaffinches living close to noisy streams, we found no significant differences in song characteristics between the town and forest populations. Our results support the antiexhaustion hypothesis because males with larger repertoires were able to sing with a significantly higher rate due to faster switching between different song types and producing shorter bouts. Sample size or population differences between our study and earlier investigations of the same species may explain the inconsistency with previous findings. Future studies should focus on determining the relations between song organisation and the directly measured quality of males and females' choice using, preferably, a longitudinal approach. 相似文献
73.
Tomasz Krzeszowski Krzysztof Przednowek Krzysztof Wiktorowicz Janusz Iskra 《Computer methods in biomechanics and biomedical engineering》2016,19(12):1319-1329
This paper presents a method of monocular human motion tracking for estimation of hurdle clearance kinematic parameters. The analysis involved 10 image sequences of five hurdlers at various training levels. Recording of the sequences was carried out under simulated starting conditions of a 110 m hurdle race. The parameters were estimated using the particle swarm optimization algorithm and they are based on analysis of the images recorded with a 100 Hz camera. The proposed method does not involve using any special clothes, markers, inertial sensors, etc. As the quality criteria, the mean absolute error and mean relative error were used. The level of computed errors justifies the use of this method to estimate hurdle clearance parameters. 相似文献
74.
Angelika Noga Edyta Skrzypek Marzena Warchoł Ilona Czyczyło-Mysza Kinga Dziurka Izabela Marcińska Katarzyna Juzoń Tomasz Warzecha Agnieszka Sutkowska Zygmunt Nita Krystyna Werwińska 《In vitro cellular & developmental biology. Plant》2016,52(6):590-597
Obtaining oat DH lines is only effective via wide crossing with maize. Seven hundred haploid embryos from 21 single F1 progeny obtained from wide crosses with maize were isolated, divided into four groups according to their size (<0.5 mm, 0.5–0.9 mm, 1.0–1.4 mm, and ≥1.5 mm), and transferred into 190–2 regeneration medium with different growth regulators: 0.5 mg L?1 kinetin (KIN) and 0.5 mg L?1 1-naphthaleneacetic acid (NAA); 1 mg L?1 zeatin (ZEA) and 0.5 mg L?1 NAA; or 1 mg L?1 dicamba (DIC), 1 mg L?1 picloram (PIC), and 0.5 mg L?1 kinetin (KIN). Among all isolated embryos, approximately 46.1% were between 1.0–1.4 mm, while the smallest group of embryos (7.1%) were those <0.5 mm. The ability of haploid embryos to germinate varied depending on oat genotypes and the size of embryos. Haploid embryos <0.5 mm were globular and did not germinate, whereas embryos ≥1.5 mm had clearly visible coleoptiles, radicles, and scutella, and were able to germinate. Germination of oat haploid embryos varied depending on growth regulators in the regeneration medium. Most haploid embryos germinated on medium with 0.5 mg L?1 NAA and 0.5 mg L?1 KIN, while the fewest germinated on medium with 1 mg L?1 DIC, 1 mg L?1 PIC, and 0.5 mg L?1 KIN. One hundred thirty germinated haploid embryos converted into haploid plants. Fifty oat DH lines were obtained after colchicine treatment. 相似文献
75.
Journal of Physiology and Biochemistry - AMP-activated protein kinase (AMPK) is present in different kinds of metabolically active cells. AMPK is an important intracellular energy sensor and plays... 相似文献
76.
Emilia Hofman‐Kamiska Herv Bocherens Dorothe G. Drucker Ralph M. Fyfe Witold Gumiski Daniel Makowiecki Martina Pacher Giedr Pili
iauskien Tomasz Samojlik Jessie Woodbridge Rafa Kowalczyk 《Global Change Biology》2019,25(9):2915-2930
Climate warming and human landscape transformation during the Holocene resulted in environmental changes for wild animals. The last remnants of the European Pleistocene megafauna that survived into the Holocene were particularly vulnerable to changes in habitat. To track the response of habitat use and foraging of large herbivores to natural and anthropogenic changes in environmental conditions during the Holocene, we investigated carbon (δ13C) and nitrogen (δ15N) stable isotope composition in bone collagen of moose (Alces alces), European bison (Bison bonasus) and aurochs (Bos primigenius) in Central and Eastern Europe. We found strong variations in isotope compositions in the studied species throughout the Holocene and diverse responses to changing environmental conditions. All three species showed significant changes in their δ13C values reflecting a shift of foraging habitats from more open in the Early and pre‐Neolithic Holocene to more forest during the Neolithic and Late Holocene. This shift was strongest in European bison, suggesting higher plasticity, more limited in moose, and the least in aurochs. Significant increases of δ15N values in European bison and moose are evidence of a diet change towards more grazing, but may also reflect increased nitrogen in soils following deglaciation and global temperature increases. Among the factors explaining the observed isotope variations were time (age of samples), longitude and elevation in European bison, and time, longitude and forest cover in aurochs. None of the analysed factors explained isotope variations in moose. Our results demonstrate the strong influence of natural (forest expansion) and anthropogenic (deforestation and human pressure) changes on the foraging ecology of large herbivores, with forests playing a major role as a refugial habitat since the Neolithic, particularly for European bison and aurochs. We propose that high flexibility in foraging strategy was the key for survival of large herbivores in the changing environmental conditions of the Holocene. 相似文献
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