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991.
Soraya Wilke Saliba Franziska Glser Anke Deckers Albrecht Keil Thomas Hurrle Matthias Apweiler Florian Ferver Nicole Volz Dominique Endres Stefan Brse Bernd L. Fiebich 《International journal of molecular sciences》2021,22(5)
Neuroinflammation is a crucial process to maintain homeostasis in the central nervous system (CNS). However, chronic neuroinflammation is detrimental, and it is described in the pathogenesis of CNS disorders, including Alzheimer’s disease (AD) and depression. This process is characterized by the activation of immune cells, mainly microglia. The role of the orphan G-protein-coupled receptor 55 (GPR55) in inflammation has been reported in different models. However, its role in neuroinflammation in respect to the arachidonic acid (AA) cascade in activated microglia is still lacking of comprehension. Therefore, we synthesized a novel GPR55 antagonist (KIT 10, 0.1–25 µM) and tested its effects on the AA cascade in lipopolysaccharide (LPS, 10 ng / mL)-treated primary rat microglia using Western blot and EIAs. We show here that KIT 10 potently prevented the release of prostaglandin E2 (PGE2), reduced microsomal PGE2 synthase (mPGES-1) and cyclooxygenase-2 (COX-2) synthesis, and inhibited the phosphorylation of Ikappa B-alpha (IκB-α), a crucial upstream step of the inflammation-related nuclear factor-kappaB (NF-κB) signaling pathway. However, no effects were observed on COX-1 and -2 activities and mitogen-activated kinases (MAPK). In summary, the novel GPR55 receptor antagonist KIT 10 reduces neuroinflammatory parameters in microglia by inhibiting the COX-2/PGE2 pathway. Further experiments are necessary to better elucidate its effects and mechanisms. Nevertheless, the modulation of inflammation by GPR55 might be a new therapeutic option to treat CNS disorders with a neuroinflammatory background such as AD or depression. 相似文献
992.
Assessing the Value and Role of Seafood Traceability from an Entire Value‐Chain Perspective 下载免费PDF全文
Brian Sterling Martin Gooch Benjamin Dent Nicole Marenick Alexander Miller Gilbert Sylvia 《Comprehensive Reviews in Food Science and Food Safety》2015,14(3):205-268
The traceability practices and systems of 48 separate seafood businesses were assessed as part of an evaluation of 9 global seafood value chains (from catch to point of sale to the consumer). The purpose was to gain insights and provide knowledge about the impact of traceability on improving seafood industry business performance, including reducing waste, and enhancing consumer trust. In addition, the project developed and delivered a tool that can be used by stakeholders that are seeking to better understand the return on investment of implementation of traceability practices and solutions. Using structured and semistructured interviews of over 80 individuals, the research revealed that traceability is more highly valued by businesses, regardless of their size, if they engage more often in highly collaborative activities with their suppliers and customers. A survey in 5 nations about consumer perceptions with regards to seafood and the key factors influencing their purchasing decisions delivered insights into the discrete choices that consumers make when buying seafood products. The consumer survey data were incorporated into a “Discrete Choice Simulator” that others can use to compare and contrast the preferences of consumers in these countries and better understand what factors regarding traceability impact on their buying decisions. The research concluded with several recommendations for businesses, governments, and nongovernment organizations. 相似文献
993.
Lauren E. Hamilton Morgan Lion Luis Aguila Joo Suzuki Genevieve Acteau Nicole Protopapas Wei Xu Peter Sutovsky Mark Baker Richard Oko 《International journal of molecular sciences》2021,22(15)
The perinuclear theca (PT) of the eutherian sperm head is a cytoskeletal-like structure that houses proteins involved in important cellular processes during spermiogenesis and fertilization. Building upon our novel discovery of non-nuclear histones in the bovine PT, we sought to investigate whether this PT localization was a conserved feature of eutherian sperm. Employing cell fractionation, immunodetection, mass spectrometry, qPCR, and intracytoplasmic sperm injections (ICSI), we examined the localization, developmental origin, and functional potential of histones from the murid PT. Immunodetection localized histones to the post-acrosomal sheath (PAS) and the perforatorium (PERF) of the PT but showed an absence in the sperm nucleus. MS/MS analysis of selectively extracted PT histones indicated that predominately core histones (i.e., H3, H3.3, H2B, H2A, H2AX, and H4) populate the murid PT. These core histones appear to be de novo-synthesized in round spermatids and assembled via the manchette during spermatid elongation. Mouse ICSI results suggest that early embryonic development is delayed in the absence of PT-derived core histones. Here, we provide evidence that core histones are de novo-synthesized prior to PT assembly and deposited in PT sub-compartments for subsequent involvement in chromatin remodeling of the male pronucleus post-fertilization. 相似文献
994.
995.
Norovirus is the principal agent of bivalve shellfish-associated gastroenteric illness worldwide. Numerous studies using PCR have demonstrated norovirus contamination in a significant proportion of both oyster and other bivalve shellfish production areas and ready-to-eat products. By comparison, the number of epidemiologically confirmed shellfish-associated outbreaks is relatively low. This suggests that factors other than the simple presence or absence of virus RNA are important contributors to the amount of illness reported. This study compares norovirus RNA levels in oyster samples strongly linked to norovirus or norovirus-type illness with the levels typically found in commercial production areas (non-outbreak-related samples). A statistically significant difference between norovirus levels in the two sets of samples was observed. The geometric mean of the levels in outbreak samples (1,048 copies per g) was almost one order of magnitude higher than for positive non-outbreak-related samples (121 copies per g). Further, while none of the outbreak-related samples contained fewer than 152 copies per g, the majority of positive results for non-outbreak-related samples was below this level. These observations support the concept of a dose-response for norovirus RNA levels in shellfish and could help inform the establishment of threshold criteria for risk management. 相似文献
996.
Nicole Stanford Jessica R. TerBush Mohan Setty Matthew R. Barnett 《Metallurgical and Materials Transactions A》2013,44(6):2466-2469
The effect of 0.3 wt pct Na on the microstructure of extruded alloy Mg-2Sn-1Zn is examined. We report that Na stabilizes the Mg2Sn phase, resulting in its precipitation during extrusion under conditions where a solid solution is otherwise expected. This effect appears to be thermodynamic in nature and is different from the kinetic enhancement of low- temperature aging reported by Mendis et al. [Phil. Mag. Letters, 86 (2006), 443]. The precipitates of the current study enable useful refinement of the grain size. 相似文献
997.
Nicole E. Zander Joshua A. Orlicki Adam M. Rawlett Thomas P. Beebe Jr. 《Journal of materials science. Materials in medicine》2013,24(1):179-187
The impact of mat porosity of polycaprolactone (PCL) electrospun fibers on the infiltration of neuron-like PC12 cells was evaluated using two different approaches. In the first method, bi-component aligned fiber mats were fabricated via the co-electrospinning of PCL with polyethylene oxide (PEO). Variation of the PEO flow rate, followed by selective removal of PEO from the PCL/PEO mesh, allowed for control of the porosity of the resulting scaffold. In the second method, aligned fiber mats were fabricated from various concentrations of PCL solutions to generate fibers with diameters between 0.13 ± 0.06 and 9.10 ± 4.1 μm. Of the approaches examined, the variation of PCL fiber diameter was found to be the better method for increasing the infiltration of PC12 cells, with the optimal infiltration into the ca. 1.5-mm-thick meshes observed for the mats with the largest fiber diameters, and hence largest pore sizes. 相似文献
998.
JN Andexer N Staunig T Eggert C Kratky M Pohl K Gruber 《Chembiochem : a European journal of chemical biology》2012,13(13):1932-1939
Hydroxynitrile lyases (HNLs) catalyze the cleavage of cyanohydrins to yield hydrocyanic acid (HCN) and the respective carbonyl compound and are key enzymes in the process of cyanogenesis in plants. In organic syntheses, HNLs are used as biocatalysts for the formation of enantiopure cyanohydrins. We determined the structure of the recently identified, R‐selective HNL from Arabidopsis thaliana (AtHNL) at a crystallographic resolution of 2.5 Å. The structure exhibits an α/β‐hydrolase fold, very similar to the homologous, but S‐selective, HNL from Hevea brasiliensis (HbHNL). The similarities also extend to the active sites of these enzymes, with a Ser‐His‐Asp catalytic triad present in all three cases. In order to elucidate the mode of substrate binding and to understand the unexpected opposite enantioselectivity of AtHNL, complexes of the enzyme with both (R)‐ and (S)‐mandelonitrile were modeled using molecular docking simulations. Compared to the complex of HbHNL with (S)‐mandelonitrile, the calculations produced an approximate mirror image binding mode of the substrate with the phenyl rings located at very similar positions, but with the cyano groups pointing in opposite directions. A catalytic mechanism for AtHNL is proposed, in which His236 from the catalytic triad acts as a general base and the emerging negative charge on the cyano group is stabilized by main‐chain amide groups and an α‐helix dipole very similar to α/β‐hydrolases. This mechanistic proposal is additionally supported by mutagenesis studies. 相似文献
999.
Meinhard von Gerkan Nikolaus Goetze Klaus Lenz Nicole Flores Martin Friedrich Jessica Last Udo Meyer Duc Tran Cong Marcus Bredt 《中国建筑装饰装修》2012,(4):238-239
穿过园林景观来访者可从四个方向进入博物馆。在正方形的建筑体中庭内,一座圆形的挑空大厅将入口层面于其上的三层展览空间连接起来。如同倒置的金字塔般,中庭向上呈阶梯状展开。来访者向外望去,仿佛"漂浮"于主题公园景观之上。盘旋上升的坡道作为极富表现力的空间元素,将人们吸引至建筑顶部,并且实现了展览空间与中庭的视线交流。由于展览空间全部安排在建筑的首层至三层,会议、科研中心,办公空间以 相似文献
1000.
Chau Hon Ho Matthias Thiel Seref Celik Erich K. Odermatt Ingo Berndt Ralf Thomann Joerg C. Tiller 《Polymer》2012,53(21):4623-4630
Hyperbranched amphiphilic polymeric systems with core–shell architecture can be used as versatile nanocontainers and templates with great potential in application fields ranging from medicine to organic coatings. In order to explore an alternative to the already widely used and established synthetic macromolecules, we synthesized new polymers based on hyperbranched polylysine. Polylysine was prepared with classical heating and microwave-assisted heating, respectively. While, the synthesis at 160 °C resulted in hyperbranched polylysine with degrees of branching (DB) between 0.50 and 0.54, the microwave-assisted heating at 200 °C resulted in highly branched polymers with DB values of 0.30–0.32. The molecular weight Mn could be controlled in a range of 5000–12,000 g/mol. The hyperbranched polylysine was hydrophobized via polymer-analogue reactions using a mixture of stearoyl/palmitoyl chloride and glycidyl hexadecyl ether, respectively. These reactions yielded in high degrees of modification (80% and 90%, respectively). The synthesized polymers are soluble in non-polar organic solvents, such as toluene and chloroform, and take up metal salts to up to 25 wt.%. They support the formation of Ag, Au, and Pd nanoparticles and nanocrystals in organic solvents and stabilize them. Thus, the here presented macromolecules are a promising readily achievable alternative to existing core–shell systems. 相似文献