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221.
Myeong Seong Sim Hye Jeong Kim Sang Hee Jo Chun Kim Il Yup Chung 《International journal of molecular sciences》2022,23(7)
Lysophosphatidylserine (LysoPS) is an amphipathic lysophospholipid that mediates a broad spectrum of inflammatory responses through a poorly characterized mechanism. Because LysoPS levels can rise in a variety of pathological conditions, we sought to investigate LysoPS’s potential role in airway epithelial cells that actively participate in lung homeostasis. Here, we report a previously unappreciated function of LysoPS in production of a mucin component, MUC5AC, in the airway epithelial cells. LysoPS stimulated lung epithelial cells to produce MUC5AC via signaling pathways involving TACE, EGFR, and ERK. Specifically, LysoPS- dependent biphasic activation of ERK resulted in TGF-α secretion and strong EGFR phosphorylation leading to MUC5AC production. Collectively, LysoPS induces the expression of MUC5AC via a feedback loop composed of proligand synthesis and its proteolysis by TACE and following autocrine EGFR activation. To our surprise, we were not able to find a role of GPCRs and TLR2, known LyoPS receptors in LysoPS-induced MUC5AC production in airway epithelial cells, suggesting a potential receptor-independent action of LysoPS during inflammation. This study provides new insight into the potential function and mechanism of LysoPS as an emerging lipid mediator in airway inflammation. 相似文献
222.
Frank H. Chung 《中国食品工业》2001,(5):18-19
<正> 众所周知,膨松剂在焙烤中的主要作用是在焙烤或混合生面团和稀面糊时提供所需气体,以使焙烤产品获得充气膨松的效果,增加体积并改善口感及外观质量。 事实上,经膨松的产品柔软、多孔并呈海绵状,具有良好的组织结构,美味可口。另一方面,用于油炸食品中的裹面包屑混合料或涂层稀面糊,膨松剂能为产品提供理想的多孔细胞结构和松脆性。 相似文献
223.
The migration of endocrine-disrupting di-(2-ethylhexyl) phthalate (DEHP) poses a serious threat to public health and the environment. In this study, we successfully prepared a plasticizerwith reduced DEHP migration by directly incorporating 2,3,6-per-O-benzoyl-beta-cyclodextrin (Bz-beta-CD) into DEHP. Bz-beta-CD was prepared by esterification between the hydroxyl groups of beta-CD and benzoyl chloride. The presence of this cyclodextrin is expected to facilitate formation of stable complexes through pi-pi association with DEHP molecules. The flexible PVC was prepared with a gelation-fusion process that uses the prepared migration-resistant plasticizer, and its properties (flexibility, thermal stability, and clarity) were evaluated by carrying out DSC and tensile testing, TGA, and haze testing, respectively. No significant changes in the physical properties of the flexible PVC were observed when Bz-beta-CD was added. DEHP migration tests were carried out for the flexible PVC according to the ISO 3826:1993(E) test method, and the quantity of migrated DEHP was then determined with UV-vis spectroscopy. It was found that the addition of Bz-beta-CD decreases the levels of DEHP migration from the flexible PVC samples by almost 40%. We investigated the molecular interaction between Bz-beta-CD and DEHP using molecular mechanics simulations, and we conclude that this reduction in DEHP migration is due to the formation of stabilized pi-pi attractive association and inclusion complexes of Bz-beta-CD and DEHP in flexible PVC. 相似文献
224.
Chien Hwa Chong Chung Lim Law Michael Cloke Luqman Chuah Abdullah Wan Ramli Wan Daud 《Drying Technology》2013,31(10):1286-1293
Sun drying of chempedak (Artocarpus integer) was carried out on different sample sizes to investigate the effects on product quality. Fick's second law model was used to determine the effective diffusivities of sun–dried chempedak slabs based on the drying rate versus moisture content plots. In addition, texture degradation and total color changes were investigated. The texture and color changes of dried chempedak were relatively significant (p < 0.05) compared to fresh chempedak. There was an increase in dried fruit hardness and chewiness but a decrease in springiness and cohesiveness during drying. 相似文献
225.
226.
Bin Tian Robert J. Sclabassi Jennting T. Hsu Qiang Liu Ching Chung Li Mingui Sun 《电子科学学刊(英文版)》2007,24(5):642-648
Research interest in multi-frame Superresolution has risen substantially in recent years.This paper presents a modified Projection Onto Convex Set (POCS) superresolution method based on wavelet transform.The method analyzes the image formation model from wavelet multiresolution analysis point of view and defines an closed convex set and its corresponding projection based on wavelet transform.An iterative procedure is utilized to reduce the estimated errors of the result image,and this guarantees the estimated image to lay in the intersection of different convex sets,thus produces a high resolution image with a reduced error.The effectiveness of the algorithm is demonstrated by experimental results. 相似文献
227.
Yee-Shan Ku Sau-Shan Cheng Ming-Sin Ng Gyuhwa Chung Hon-Ming Lam 《International journal of molecular sciences》2022,23(5)
In plants, the translocation of molecules, such as ions, metabolites, and hormones, between different subcellular compartments or different cells is achieved by transmembrane transporters, which play important roles in growth, development, and adaptation to the environment. To facilitate transport in a specific direction, active transporters that can translocate their substrates against the concentration gradient are needed. Examples of major active transporters in plants include ATP-binding cassette (ABC) transporters, multidrug and toxic compound extrusion (MATE) transporters, monosaccharide transporters (MSTs), sucrose transporters (SUTs), and amino acid transporters. Transport via ABC transporters is driven by ATP. The electrochemical gradient across the membrane energizes these secondary transporters. The pH in each cell and subcellular compartment is tightly regulated and yet highly dynamic, especially when under stress. Here, the effects of cellular and subcellular pH on the activities of ABC transporters, MATE transporters, MSTs, SUTs, and amino acid transporters will be discussed to enhance our understanding of their mechanics. The relation of the altered transporter activities to various biological processes of plants will also be addressed. Although most molecular transport research has focused on the substrate, the role of protons, the tiny counterparts of the substrate, should also not be ignored. 相似文献
228.
Chun-Hou Liao Kau-Han Lee Shiu-Dong Chung Kuo-Chiang Chen Chellappan Praveen Rajneesh Bo-He Chen Jai-Hong Cheng Wang-Ying Lin Han-Sun Chiang Yi-No Wu 《International journal of molecular sciences》2022,23(6)
Erectile dysfunction (ED) is an agonizing complication of diabetes mellitus (DM) and it is challenging to treat ED in DM patients. Platelet-rich plasma (PRP) is a unique therapeutic strategy comprising intrinsic growth factors. An attempt was made to explore the potentiality of the PRP treatment in DM-induced ED rats in various groups (control, DM-non-ED, DM-ED, and DM-ED treated with PRP). Streptozotocin (STZ) was used to induce DM in rats. The blood glucose levels of the DM rats were maintained at >300 mg/dl. In the 18-week experiment, survival rate, body weight, intracavernous pressure (ICP) variations, and arterial blood pressure were analyzed. The tissue restoration results were validated by histological, immunofluorescence, and transmission electron microscopic analysis. PRP treatment of DM-ED rats significantly increased all parameters of erectile function compared to pre-treatment of PRP and DM-ED treated with vehicle. The histological results revealed that PRP treatment substantially enhanced the regeneration of myelinated nerves and decreased the atrophy of corporal smooth muscle. Notably, the PRP treatment immensely enhanced the survival rate in post-surgery DM-ED rats. These results indicated certain benefits of PRP treatment in delaying damage and preventing post-surgery complications in DM patients. Hence, PRP treatment is a novel multifactorial strategy for DM-ED patients. 相似文献
229.
Temperatures and concentrations of OH radicals in silica generating counterflow oxy-hydrogen diffusion flames are measured using a broadband coherent anti-Stokes Raman spectroscopy (CARS) and a planar laser induced fluorescence (PLIF) techniques to study thermo-chemical effects of SiCl4 addition to flames. Numerical analysis considering detailed chemical reactions including silica generating reactions is also conducted. The experimental results demonstrate that temperatures decrease in preheated zone due to the increase in specific heat of the gas mixture while the decrease is mitigated in particle formation zone due to the heat release through hydrolysis and oxidation reactions of SiCl4. Also, OH concentrations significantly decrease in silica formation flame, which can be attributed to the consumption of oxidative radicals during the silica generating reactions of SiCl4 and depletion of OH by HCl. The numerical simulation agrees well for flames having relatively low flame temperatures of 1750 K but underestimates the decrease in OH concentration for high temperature flame over 2700 K. The disagreement for the high temperature flames would imply possible OH consumption via direct reactions between OH radicals and silicon chlorides, which is expected to be highly sensitive to temperature. 相似文献
230.
Siang Chen Wu Pi Fen Lu Yu Chien Lin Pei Chung Chen Chi Mei Lee 《International Journal of Hydrogen Energy》2012
Photobiological H2 production is a promising method for renewable energy development. An innovative system that co-cultivating Rhodopseudomonas palustris WP3-5 and Anabaena sp. CH3 was carried out to estimate the effect of co-cultivation on H2 production enhancement. H2 production prolongation and enhancement were observed due to the light and metabolic compatibility of these two strains. Co-culture system served by acetate and fructose as carbon source can accumulate H2 in 140.8 mL, almost double than the sum of individuals. Moreover, the enhancement of H2 production was significantly affected by the mixed ratio of two strains. The mixed ratio (WP3-5:CH3) of 1:2 showed a highest H2 production rate in 44.8 mL-H2/L-culture/h, and both 2:1 and 1:2 exhibited a relatively high substrate conversion efficiency during the latest period of cultivation, whereas the mixed ratio of 1:1 and 3:1 only revealed a prolongation in H2 production due to metabolic compatibility of two strains. 相似文献