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991.
992.
The fluorescence quenching resolved spectra and red-edge excitation fluorescence measurements of human alpha 1-proteinase inhibitor 总被引:1,自引:0,他引:1
The human alpha 1-proteinase inhibitor (alpha 1-PI) and its reactive site modified form (alpha 1-PI*) have been examined using the fluorescence quenching resolved spectra method. The red-edge excitation measurements were applied for the study of structural differences between these forms. The crystallographic data of alpha 1-PI* structure have shown that its polypeptide chain includes only two tryptophan residues. The fluorescence quenching data have indicated that the conversion of the intact inhibitor molecule into its nicked form is accompanied by changes in the tryptophan environments. The red-edge excitation measurements have proved that the dipolar relaxation process around the Trp-194 residue is much bigger in alpha 1-PI* form than in the nicked one. 相似文献
993.
We showed in Drosophila that nuclear migration was reduced all through cleavage stages in embryos with any one of the maternal-effect mutations, gs(1)N441 and gs(1)N26 , in which F-actin reorganization in cleavage embryos is disordered. Moreover, we determined nuclear positions in embryos at cycle 1 and 2 in the wild type and two mutants, gs(1)N441 and gs(1)N26 , in order to test if the nuclear migration is regulated within a nuclear cycle. At cycle 1, there was no difference in nuclear position among the strains that we observed. At cycle 2 the two sister nuclei had already migrated posteriorly in the wild type. However, migration was not detectable at cycle 2 in the mutants. Besides, the two sister nuclei were less-separated from each other, and orientation of the two nuclei with regard to the anteroposterior axis was random, different from the wild type. These results support the hypothesis that F-actin is involved in the regulation to separate cleavage nuclei from each other and from the egg cortex. This regulation is apparently required for posteriorward nuclear migration, and for synchronous nuclear arrival in the whole egg cortex. 相似文献
994.
Joo Young Huh Seulah Lee Eun-Bi Ma Hee Jeong Eom Jiwon Baek Yoon-Joo Ko 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):1167-1173
Betula platyphylla var. japonica (Betulaceae) has been used traditionally in Asian countries for the treatment of inflammatory diseases. A recent study has reported a phenolic compound, platyphylloside from B. platyphylla, that shows inhibition on adipocyte differentiation and induces lipolysis in 3T3-L1 cells. Based on this finding, we conducted phytochemical analysis of the EtOH extract of the bark of B. platyphylla var. japonica, which resulted in the isolation of phenolic glycosides (1–4). Treatment of the isolated compounds (1–4) during adipocyte differentiation of 3T3-L1 mouse adipocytes resulted in dose-dependent inhibition of adipogenesis. In mature adipocytes, arylbutanoid glycosides (2–4) induced lipolysis related genes HSL and ATGL, whereas catechin glycoside (1) had no effect. Additionally, arylbutanoid glycosides (2–4) also induced GLUT4 and adiponectin mRNA expression, indicating improvement in insulin signaling. This suggests that the isolates from B. platyphylla var. japonica exert benefial effects in regulation of adipocyte differentiation as well as adipocyte metabolism. 相似文献
995.
Background
Hypovitaminosis D is prevalent worldwide. It is more prevalent in Eastern Asia region, including Korea. In addition to various environmental factors that influence serum 25-hydroxyvitamin D (25(OH)D) concentration, genetic influence also plays a significant role based on studies estimating the heritability of 25(OH)D in non-Asian populations. The objective of this study was to determine the genetic influence on serum 25(OH)D concentration in Korean men using the twin and family data.Methods
A total of 1126 Korean male adult twins and family members from the Healthy Twin Study with serum 25(OH)D measurement were included in this cross-sectional study. Intraclass correlation coefficients (ICCs) and heritability were calculated by mixed linear regression analysis and quantitative genetic analysis after adjusting for environmental and lifestyle factors.Results
Mean (±?standard deviation; SD) of serum 25(OH)D concentration was 15.34?±?6.18?ng/ml. The prevalence of vitamin D insufficiency was 19.8% and that of vitamin D deficiency was 77.9%. After adjusting for age, the highest ICC (0.61) was observed for monozygotic twin pairs while the lowest ICC (0.31) was found for father-son pairs. Age-adjusted heritability was estimated to be 58%. When physical activity, multivitamin intake and season of blood sampling were further considered, the ICC and heritability did not materially change. In the sensitivity analysis after excluding known multivitamin users, age-adjusted heritability was reduced to 44%.Conclusions
In our study of Korean male twins and family members, heritability of 25(OH)D was moderately high. This supports the finding that genetic factors have significant influence on vitamin D status.996.
In silico identification,characterization and expression analysis of attacin gene family in response to bacterial and fungal pathogens in Tenebrio molitor 下载免费PDF全文
997.
Magdalena Wójcik-Jagła Anna Fiust Janusz Kościelniak Marcin Rapacz 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2018,131(1):167-181
Key message
Association mapping of drought-related traits in barley was used to increase the density of existing QTL maps without recreating mapping populations.Abstract
We used 109 spring barley genotypes exhibiting high or low drought tolerance to elucidate the associations between diversity array technology sequencing (DArTseq) and single nucleotide polymorphism (SNP) markers and various physiological parameters related to plant responses to drought conditions. The study was performed in controlled conditions (growth chambers), drought tolerance was phenotyped in the four-leaf seedlings. We identified 58 associations including 34 new markers (i.e., 16 DArTseq and 18 SNP markers). The results for three markers were consistent with the data obtained in an earlier traditional biparental QTL mapping study. The regions neighboring markers on linkage group 2H contained the highest number of significant marker–trait associations. Five markers related to the photosynthetic activity of photosystem II were detected on chromosome 4H. The lowest number of associations were observed for the sequences neighboring DArT markers on linkage group 6H. A chromosome 3H region related to water use efficiency and net photosynthesis rate in both biparental QTL, and association study, may be particularly valuable, as these parameters correspond to the ability of plants to remain highly productive under water deficit stress. Our findings confirm that association mapping can increase the density of existing QTL maps without recreating mapping populations.998.
Jing Wang Chun-Chi Chen Yunyun Yang Weidong Liu Tzu-Ping Ko Na Shang Xiangying Hu Yonghua Xie Jian-Wen Huang Yonghui Zhang Rey-Ting Guo 《Biochemical and biophysical research communications》2018,495(2):1782-1788
FamD1 is a novel CloQ/NphB-family indole prenyltransferase which involves in hapalindole-type alkaloid biosynthesis. Here the native FamD1 structure and three protein-ligand complexes are analyzed to investigate the molecular basis of substrate binding and catalysis. FamD1 adopts a typical ABBA architecture of aromatic prenyltransferase, in which the substrate-binding chamber is found in the central β-barrel. The indole-containing acceptor substrate is bound adjacent to the prenyl donor. Based on the complex structures, a catalytic mechanism of FamD1 is proposed. Functional implications on the sister enzyme FamD2 are also discussed. 相似文献
999.
Tayfun Yazıcı Gülperi Koçer Mustafa Nazıroğlu İshak Suat Övey Ahmi Öz 《Biological trace element research》2018,184(2):358-368
Increased intracellular free calcium ion (Ca2+) concentration induces excessive oxidative stress and apoptosis. Medical procedures such as zoledronic acid (Zol), bevacizumab (Bev), and dexamethasone (Dex) are usually used in the treatment of bone diseases (osteoporosis, Paget’s disease, etc.) and to prevent metastasis in the bone although the procedures induce osteonecrosis of the jaw through excessive production of reactive oxygen species (ROS). Recently, we observed regulator roles of selenium (Se) on apoptosis and Ca2+ entry through transient receptor potential vanilloid 1 (TRPV1) channels in the cancer cell lines. Therefore, Se may modulate Zol, Bev, and Dex-induced oxidative stress and apoptosis through regulation of TRPV1 channel. In the current study, we investigated the protective effects of Se on apoptosis and oxidative stress through TRPV1 in Zol, Bev, and Dex-induced osteoblast-like cell line. We used human osteoblast-like cell line (Saos-2), and the cells were divided into 12 groups as control, Zol, Bev, Dex, Se, Zol+Se, Bev+Se, Dex+Se, Zol+Dex, Zol+Dex+Se, Zol+Bev, and Zol+Bev+Se which were incubated with drugs (Zol, Bev, Dex, and Se) for 24 h. The cytosolic free Ca2+ concentration was increased by Zol, Bev, Dex, Zol+Bev, and Zol+Dex, although it was reduced by Se treatment. However, Zol, Bev, and Dex-induced increase in apoptosis, caspase 3, caspase 9, poly (ADP-ribose) polymerase 1 expression levels, and intracellular ROS production values in the cells were decreased by Se treatments. In conclusion, we observed that Zol, Bev, and Dex-induced apoptosis, mitochondrial oxidative stress, and calcium signaling are decreased in human osteoblast-like cell line by the Se treatment. Our findings may be relevant to the etiology and treatment of Zol, Bev, and Dex-induced osteonecrosis by Se. 相似文献
1000.
Lenka Hájková Zdeněk Hubálek Věra Kožnarová Lenka Bartošová Martin Možný 《Aerobiologia》2018,34(2):157-169
This paper analyses long-term (1960–2015) onset of flowering in 16 native terrestrial plants (11 of them produce important allergens) recorded in different parts of the Czech Republic (southern, central and northern part) in relation to the North Atlantic Oscillation (NAO) index of the preceding winter and thermal data—growing degree-days (GDD) and soil temperature. Flowering occurred significantly earlier following positive winter NAO phases (causing spring to be warmer than normal in Central Europe) in nearly all early-flowering (February, March, April) species; high Pearson correlation values were recorded in, e.g. wood anemone, common snowdrop, goat willow, common hazel and common alder. There was found a difference between the southern and northern part of the country, e.g. in silver birch and pedunculate oak. Out of the later-flowering (May–July) plant species, black elder and meadow foxtail also significantly correlated with the winter NAO index, lime tree correlated less markedly. The best results of a threshold for calculation of GDD to onset of beginning of flowering were found in lime tree—it was 5 °C at all three stations. Results of other taxa were more variable (e.g. 4–7 °C in goat willow; 6–10 °C in silver birch). Pearson correlation coefficients between NAO index and GDD were negative in lime tree at all thresholds (5, 6, 7, 8, 9, 10 °C), while goat willow and silver birch were not so uniform (both positive and negative values). Correlation coefficients between phenophase onset and soil temperature (10 cm depth) had the highest values in silver birch, European larch and wood anemone. Stations situated at higher elevation showed negative correlation coefficient with soil temperature in common snowdrop, pedunculate oak, meadow foxtail and lime tree; other values were positive. 相似文献