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51.
Luqing Zhang Humphrey A. Mabwi Norberto J. Palange Ruirui Jia Jun Ma Fatoumata Binta Bah Rajiv Kumar Sah Dan Li Daji Wang Fatoumata Binta Maci Bah Jacques Togo Honghong Jin Luying Ban Xuechao Feng Yaowu Zheng 《PloS one》2015,10(11)
Disconnected (disco)-interacting protein 2 homolog A is a member of the DIP2 protein family encoded by Dip2a gene. Dip2a expression pattern has never been systematically studied. Functions of Dip2a in embryonic development and adult are not known. To investigate Dip2a gene expression and function in embryo and adult, a Dip2a-LacZ mouse model was generated by insertion of β-Gal cDNA after Dip2a promoter using CRISPR/Cas9 technology. Dip2a-LacZ mouse was designed to be a lacZ reporter mouse as well as a Dip2a knockout mouse. Heterozygous mice were used to study endogenous Dip2a expression and homozygotes to study DIP2A-associated structure and function. LacZ staining indicated that Dip2a is broadly expressed in neuronal, reproductive and vascular tissues, as well as in heart, kidney, liver and lung. Results demonstrate that Dip2a is expressed in ectoderm-derived tissues in developing embryos. Adult tissues showed rich staining in neurons, mesenchymal, endothelial, smooth muscle cells and cardiomyocytes by cell types. The expression pattern highly overlaps with FSTL1 and supports previous report that DIP2A to be potential receptor of FSTL1 and its protective roles of cardiomyocytes. Broad and intense embryonic and adult expression of Dip2a has implied their multiple structural and physiological roles. 相似文献
52.
Cognitive Changes during Prolonged Stay at High Altitude and Its Correlation with C-Reactive Protein
Hypersensitive C-reaction protein (hsCRP) may be a risk factor for cognitive impairment resulting from Alzheimer’s disease (AD), stroke, and vascular dementia. This study explored the correlation of peripheral blood hsCRP level with cognitive decline due to high altitude exposure. The study was conducted on 100 male military participants who had never been to high altitude. Cerebral oxygen saturation monitoring, event related potentials (P300, N200) detection, and neurocognitive assessment was performed and total hsCRP, interleukin-6 (IL-6), and homocysteine was estimated at 500m altitude, 3650m altitude, 3day, 1, and 3 month post arriving at the base camp (4400m), and 1 month after coming back to the 500m altitude. High altitude increased brain oxygen saturation, prolonged P300 and N200 latencies, injured cognitive functions, and raised plasma hsCRP levels. But they all recovered in varying degrees at 1 and 3 month post arriving at the base camp (4400m). P300 latencies and hsCRP levels were strongly correlated to cognitive performances. These results suggested that cognitive deterioration occurred during the acute period of exposure to high altitude and may recover probably owning to acclimatization after extended stay at high altitude. Plasma hsCRP is inversely correlated to neurological cognition and it may be a potential biomarker for the prediction of high altitude induced cognitive dysfunction. 相似文献
53.
For high-dimensional and massive data sets, traditional centralized gene expression programming (GEP) or improved algorithms lead to increased run-time and decreased prediction accuracy. To solve this problem, this paper proposes a new improved algorithm called distributed function mining for gene expression programming based on fast reduction (DFMGEP-FR). In DFMGEP-FR, fast attribution reduction in binary search algorithms (FAR-BSA) is proposed to quickly find the optimal attribution set, and the function consistency replacement algorithm is given to solve integration of the local function model. Thorough comparative experiments for DFMGEP-FR, centralized GEP and the parallel gene expression programming algorithm based on simulated annealing (parallel GEPSA) are included in this paper. For the waveform, mushroom, connect-4 and musk datasets, the comparative results show that the average time-consumption of DFMGEP-FR drops by 89.09%%, 88.85%, 85.79% and 93.06%, respectively, in contrast to centralized GEP and by 12.5%, 8.42%, 9.62% and 13.75%, respectively, compared with parallel GEPSA. Six well-studied UCI test data sets demonstrate the efficiency and capability of our proposed DFMGEP-FR algorithm for distributed function mining. 相似文献
54.
Drawing upon the Landsat satellite images of Nanjing from 1985, 1995, 2001, 2007, and 2013, this paper integrates the convex hull analysis and common edge analysis at double scales, and develops a comprehensive matrix analysis to distinguish the different types of urban land expansion. The results show that Nanjing experienced rapid urban expansion, dominated by a mix of residential and manufacturing land from 1985 to 2013, which in turn has promoted Nanjing’s shift from a compact mononuclear city to a polycentric one. Spatial patterns of three specific types of growth, namely infilling, extension, and enclave were quite different in four consecutive periods. These patterns result primarily from the existing topographic constraints, as well as government-oriented urban planning and policies. By intersecting the function maps, we also reveal the functional evolution of newly-developed urban land. Moreover, both self-enhancing and mutual promotion of the newly developed functions are surveyed over the last decade. Our study confirms that the integration of a multi-scale method and multi-perspective analysis, such as the spatiotemporal patterns and functional evolution, helps us to better understand the rapid urban growth in China. 相似文献
55.
S-adenosylmethionine stimulates fatty acid metabolism-linked gene expression in porcine muscle satellite cells 总被引:2,自引:0,他引:2
Evidence indicates that both S-adenosylmethionine (SAMe) metabolism and intramuscular fat are associated with insulin resistance
and type II diabetes. However, it is still unknown whether SAMe have effects on intramuscular adipogenesis. The present study
investigated the roles of SAMe in the adipogenic differentiation of porcine muscle satellite cells. Cells isolated from neonatal
pig muscle were treated with different concentrations of SAMe (0, 0.5 and 1.0 mM) for 24 h, induced for a 9-day adipogenic
differentiation and were finally stained by oil red O staining. The adipocyte determination and differentiation factor-1 (ADD1)
and peroxisome proliferator-activated receptor gamma (PPARγ) mRNA and protein were stimulated by SAMe treatment in a dose-dependent
manner. Lipoprotein lipase (LPL) mRNA and protein were enhanced in 1.0 mM treatment group, compared with the control. No significant
difference was observed in the intracellular lipid content among treatments. These results provide evidence that SAMe may
be associated with intramuscular adipogenesis and indicate a novel action of SAMe in fat metabolism. 相似文献
56.
57.
Qi-Feng Wang Yue Zhao Qiong Yi Kun-Zhi Li Yong-Xiong Yu Li-Mei Chen 《Acta Physiologiae Plantarum》2010,32(6):1209-1220
Numerous studies with transgenic plants have demonstrated that overexpression of enzymes related to organic acid metabolism
under the control of CaMV 35S promoter increased organic acid exudation and Al-resistance. The synthesis of organic acids
requires a large carbon skeleton supply from leaf photosynthesis. Thus, we produced transgenic tobacco overexpressing cytosolic
malate dehydrogenase (MDH) cDNA from Arabidopsis thaliana (amdh) and the MDH gene from Escherichia coli (emdh), respectively, under the control of a leaf-specific light-inducible promoter (Rubisco small subunit promoter, PrbcS) in
the present study. Our data indicated that an increase (120–130%) in MDH-specific activity in leaves led to an increase in
malate content in the transgenic tobacco leaves and roots as well as a significant increase in root malate exudation compared
with the WT plants under the acidic (pH 4.5) conditions irrespective of 300 μM Al3+ stress absence or presence. After being exposed to 25 μM Al3+ in a hydroponic solution, the transgenic plants exhibited stronger Al-tolerance than WT plants and the degree of A1 tolerance
in the transgenic plants corresponded with the amount of malate secretion. When grown in an Al-stress perlite medium, the
transgenic tobacco lines showed better growth than the WT plants. The results suggested that overexpression of MDH driven
by the PrbcS promoter in transgenic plant leaves enhanced malate synthesis and improved Al-resistance. 相似文献
58.
59.