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991.
Jinge Yang Guang Zhang Man Wu Qiquan Shang Lin Huang Huabei Jiang 《Journal of biophotonics》2019,12(6)
Monitoring the blood supply in the lower extremities is critical for individuals who are vulnerable to vascular dysfunction. Current clinical approaches are ineffective in observing hemodynamic changes in peripheral vessels. In this paper, we investigate the potential of photoacoustic tomography (PAT) as an alternative way to in vivo monitor hemodynamic changes in foot vessels. High spatial and temporal resolution maps of hemoglobin in major arteries and veins are shown. Results from twelve human subjects are presented here to visualize vascular perfusion of healthy volunteers in two age groups (young vs aged). Significant differences between the two groups are observed and verify the declining in vascular function with aging, highlighting the potential of PAT as a new tool to evaluate vascular function in the lower extremities. 相似文献
992.
993.
Duan Yafei Zhang Jiasong Huang Jianhua Jiang Shigui 《Probiotics and antimicrobial proteins》2019,11(3):938-945
Probiotics and Antimicrobial Proteins - The present study investigated the effects of the dietary probiotic Clostridium butyricum (CB) on the growth, intestine digestive enzyme activity,... 相似文献
994.
Mingyi Wang Nanshou Wu Hongheng Huang Jiaxiong Luo Gongpu Lan Yaguang Zeng Xuehua Wang Honglian Xiong Dingan Han Haishu Tan 《Journal of biophotonics》2019,12(5)
A large‐depth‐of‐field full‐field optical angiography (LD‐FFOA) method is developed to expand the depth‐of‐field (DOF) using a contrast pyramid fusion algorithm (CPFA). The absorption intensity fluctuation modulation effect is utilized to obtain full‐field optical angiography (FFOA) images at different focus positions. The CPFA is used to process these FFOA images with different focuses. By selecting high‐contrast areas, the CPFA can highlight the characteristics and details of blood vessels to obtain LD‐FFOA images. In the optimal case of the proposed method, the DOF for FFOA is more than tripled using 10 differently focused FFOA images. Both the phantom and animal experimental results show that the LD‐FFOA resolves FFOA defocusing issues induced by surface and thickness inhomogeneities in biological samples. The proposed method can be potentially applied to practical biological experiments. 相似文献
995.
996.
Xiying Guo Haowen Liu Zhigang Huang Yanting Wang Yan Zhang Lu-Yang Wang 《Channels (Austin, Tex.)》2019,13(1):17-32
Large-conductance Ca2+-activated K+ (BK) channels are composed of a pore-forming α and a variable number of auxiliary β subunits and play important roles in regulating excitability, action potential waveforms and firing patterns, particularly in neurons and endocrine and cardiovascular cells. The β2 subunits increase the diversity of gating and pharmacological properties. Its extracellular loop contains eight cysteine residues, which can pair to form a high-order structure, underlying the stability of the extracellular loop of β2 subunits and the functional effects on BK channels. However, how these cysteines form disulfide bonds still remains unclear. To address this, based on the fact that the rectification and association of BK α to β2 subunits are highly sensitive to disruption of the disulfide bonds in the extracellular loop of β2, we developed a rectification ratio based assay by combining the site-directed mutagenesis, electrophysiology and enzymatic cleavage. Three disulfide bonds: C1(C84)-C5(C113), C3(C101)-C7(C148) and C6(C142)-C8C(174) are successfully deduced in β2 subunit in complex with a BK α subunit, which are helpful to predict structural model of β2 subunits through computational simulation and to understand the interface between the extracellular domain of the β subunits and the pore-forming α subunit. 相似文献
997.
Juo-Han Lin Wen-Jui Lee Han-Chung Wu Chih-Hsiung Wu Li-Ching Chen Chi-Cheng Huang 《Cell Adhesion & Migration》2019,13(1):121-138
The function of small G protein signalling modulators (SGSM1/2/3) in cancer remains unknown. Our findings demonstrated that SGSM2 is a plasma membrane protein that strongly interacted with E-cadherin/β-catenin. SGSM2 downregulation enhanced the phosphorylation of focal adhesion kinase (FAK; Y576/577), decreased the expression of epithelial markers such as E-cadherin, β-catenin, and Paxillin, and increased the expression of Snail and Twist-1, which reduced cell adhesion and promoted cancer cell migration. Oestrogen and fibronectin treatment was found to promote the colocalization of SGSM2 at the leading edge with phospho-FAK (Y397). The BioGRID database showed that SGSM2 potentially interacts with cytoskeleton remodelling and cell-cell junction proteins. These evidences suggest that SGSM2 plays a role in modulating cell adhesion and cytoskeleton dynamics during cancer migration. 相似文献
998.
Saber Khederzadeh Szilvia Kusza Cui‐Ping Huang Nickolay Markov Massimo Scandura Elmar Babaev Nikica prem Ivan V. Seryodkin Ladislav Paule Ali Esmailizadeh Hai‐Bing Xie Ya‐Ping Zhang 《Ecology and evolution》2019,9(17):9467-9478
The phylogeography of the European wild boar was mainly determined by postglacial recolonization patterns from Mediterranean refugia after the last ice age. Here we present the first analysis of SNP polymorphism within the complete mtDNA genome of West Russian (n = 8), European (n = 64), and North African (n = 5) wild boar. Our analyses provided evidence of unique lineages in the East‐Caucasian (Dagestan) region and in Central Italy. A phylogenetic analysis revealed that these lineages are basal to the other European mtDNA sequences. We also show close connection between the Western Siberian and Eastern European populations. Also, the North African samples were clustered with the Iberian population. Phylogenetic trees and migration modeling revealed a high proximity of Dagestan sequences to those of Central Italy and suggested possible gene flow between Western Asia and Southern Europe which was not directly related to Northern and Central European lineages. Our results support the presence of old maternal lineages in two Southern glacial refugia (i.e., Caucasus and the Italian peninsula), as a legacy of an ancient wave of colonization of Southern Europe from an Eastern origin. 相似文献
999.
Kazuki Yoshida Sachiyo Sanada‐Morimura Shou‐Horng Huang Makoto Tokuda 《Ecology and evolution》2019,9(14):8214-8224
The small brown planthopper Laodelphax striatellus (Hemiptera: Delphacidae) is reported to have the endosymbiont Wolbachia, which shows a strong cytoplasmic incompatibility (CI) between infected males and uninfected females. In the 2000s, female‐biased L. striatellus populations were found in Taiwan, and this sex ratio distortion was the result of male‐killing induced by the infection of another endosymbiont, Spiroplasma. Spiroplasma infection is considered to negatively affect both L. striatellus and Wolbachia because the male‐killing halves the offspring of L. striatellus and hinders the spread of Wolbachia infection via CI. Spiroplasma could have traits that increase the fitness of infected L. striatellus and/or coexisting organisms because the coinfection rates of Wolbachia and Spiroplasma were rather high in some areas. In this study, we investigated the influences of the infection of these two endosymbionts on the development, reproduction, and insecticide resistance of L. striatellus in the laboratory. Our results show that the single‐infection state of Spiroplasma had a negative influence on the fertility of L. striatellus, while the double‐infection state had no significant influence. At late nymphal and adult stages, the abundance of Spiroplasma was lower in the double‐infection state than in the single‐infection state. In the double‐infection state, the reduction of Spiroplasma density may be caused by competition between the two endosymbionts, and the negative influence of Spiroplasma on the fertility of host may be relieved. The resistance of L. striatellus to four insecticides was compared among different infection states of endosymbionts, but Spiroplasma infection did not contribute to increase insecticide resistance. Because positive influences of Spiroplasma infection were not found in terms of the development, reproduction, and insecticide resistance of L. striatellus, other factors improving the fitness of Spiroplasma‐infected L. striatellus may be related to the high frequency of double infection in some L. striatellus populations. 相似文献
1000.
Longsheng Huang Bing Wang Xiang Niu Peng Gao Qingfeng Song 《Ecology and evolution》2019,9(7):3700-3716
China's Natural Forest Conservation Program (NFCP) is aimed at improving the fragile and unstable ecological environment and has become one of the largest ecological restoration programs in the world because of its enormous investment and effects. It is important to work out and strengthen new measures to overcome difficulties to promote more ecosystem services and human well‐being in the NFCP. This study focused on how to evaluate the ecosystem services change brought about by implementing the NFCP. Taking the key state‐owned forest areas in the Northeast and Inner Mongolia as the study area, we provide a basic overview of development and construct an evaluation index system and a distributed calculation method for the NFCP to analyze the implications of the NFCP on ecosystem services combined with multi‐source data coupling. An evaluation index system for NFCP ecosystem services was constructed. The system includes five ecological service functions and 12 evaluation indices. The trade‐off and/or synergistic analysis of ecosystem services were carried out. The regional characteristics and changes in the NFCP ecosystem services were emphasized. Although it has not been implemented for a long time, the NFCP has had a great impact on ecosystem services because it reduces soil and water losses, increases soil fertility, strengthens the forest carbon sink and helped the forest accumulate nutrients and purify the atmosphere. Socioeconomic factors affect the NFCP ecosystem services, such as the implementation area of NFCP, investment amount of NFCP, area ratio of nature reserves, and yield of tree stock volume. Policy drivers of the NFCP, changes in the economic structure and reductions in forest yield are the main factors affecting the change in NFCP ecosystem services. Although the NFCP has positively affected the society, the economy, and the ecological environment, it has also generated some problems, such as the improper management of forest resources, shortage of capital investment, staff transfer, etc. The social and economic problems will be transient with implementation of the NFCP, and the structural changes in forestry and agriculture may eventually benefit the forestry workers and other stakeholders. 相似文献