68 research outputs found
CD100 up-Regulation Induced by Interferon-α on B Cells Is Related to Hepatitis C Virus Infection
Objectives: CD100, also known as Sema4D, is a member of the semaphorin family and has important regulatory functions that promote immune cell activation and responses. The role of CD100 expression on B cells in immune regulation during chronic hepatitis C virus (HCV) infection remains unclear. Materials and Methods: We longitudinally investigated the altered expression of CD100, its receptor CD72, and other activation markers CD69 and CD86 on B cells in 20 chronic HCV-infected patients before and after treatment with pegylated interferon-alpha (Peg-IFN-α) and ribavirin (RBV) by flow cytometry. Results: The frequency of CD5+ B cells as well as the expression levels of CD100, CD69 and CD86 was significantly increased in chronic HCV patients and returned to normal in patients with sustained virological response after discontinuation of IFN-α/RBV therapy. Upon IFN-α treatment, CD100 expression on B cells and the two subsets was further up-regulated in patients who achieved early virological response, and this was confirmed by in vitro experiments. Moreover, the increased CD100 expression via IFN-α was inversely correlated with the decline of the HCV-RNA titer during early-phase treatment. Conclusions: Peripheral B cells show an activated phenotype during chronic HCV infection. Moreover, IFN-α therapy facilitates the reversion of disrupted B cell homeostasis, and up-regulated expression of CD100 may be indirectly related to HCV clearance
State funded places in independent day schools before 1976
Transfection efficiency of Ad-A20 and Ad-ABIN1. Transfection efficiencies were determined using signals of GFP co-expression from Ad-A20 and Ad-ABIN1 vectors. The efficiencies were approximately > 90 %. (TIFF 2031 kb
Comparative Analysis of the nrDNA Repeat Unit of Manila Clam Ruditapes philippinarum and Quahog Mercenaria mercenaria
Ruditapes philippinarum and Mercenaria mercenaria are economically important bivalve species. The complete ribosomal DNA (rDNA) unit sequences of R. philippinarum and M. mercenaria, with as-sembled rDNA unit lengths of 12,910 and 12,100 bp, respectively, were obtained in this study for the first time. The rDNA unit structural organisation was similar to that in other eukaryotes, in-cluding the following elements in order: 18S rRNA-internal transcribed spacer 1 (ITS1); 5.8S rRNA-ITS2-28S rRNA-intergenic spacer (IGS) (3′ external transcribed spacer (ETS); non-transcribed spacer (NTS)-5′ ETS). The genetic differences between R. philippinarum and M. mercenaria were mainly attributable to non-coding regions (ITS1, ITS2 and IGS), especially the IGS region. The boundaries of putative 3′ ETS, NTS and 5′ ETS were confirmed. Seven and three sub-repeat fragments were found in R. philippinarum and M. mercenaria, respectively. These frag-ments ranged from 4 to 154 bp in length, and were located at the NTS and 5′ ETS regions. Five and six cytosine–guanine (CpG) islands were detected in R. philippinarum and M. mercenaria, respec-tively, and these covered 85.58% and 79.29% of the entire IGS sequence, respectively. The phylo-genetic tree was constructed based on Veneridae ITS and 18S rRNA sequences using the maxi-mum likelihood (ML) method. The ML tree based on ITS revealed that species within the same genus clearly clustered together with relatively high supporting values, and all the genera were recovered as monophyletic. The phylogenetic analyses using 18S rRNA provided a weaker phy-logenetic signal than ITS
Influence of lithium hexafluorophosphate/ethylene carbonate/dimethyl carbonate electrolyte soaking on heat seal strength of polyamide 6/aluminum/cast-polypropylene laminates used as lithium-ion battery packaging
The heat-seal strength of polymer-metal-polymer laminates, widely used in the packaging industry and more recently for pouch lithium-ion batteries, is a critical factor for the integrity of flexible package structures during service. The influences of lithium hexafluorophosphate/ethylene carbonate/dimethyl carbonate (LiPF6/EC/DMC) electrolyte soaking time and storage temperature on heat-seal strength were investigated through T-peel testing using a universal testing machine. Sealed multilayer laminates' heat-seal strength and their failure modes were measured for specimens sealed at various heat-sealing temperatures and dwell times before and after exposure to room temperature and 60? soaking conditions. The soaking condition significantly influences heat-seal strength, especially for the packages heat-sealed at low temperatures and short heat-sealing times. Higher storage temperature during electrolyte-soaking accelerates the heat-seal strength decrease. Failure modes are affected by the soaking conditions and become more complicated than the packages without soaking. The optimized heat-sealing processing window is obtained under a certain soaking condition. The electrolyte hydrogen ion concentration (pH) decreases with longer soaking time and higher storage temperature, indicating that acidification may also contribute to decreased heat-seal strength. The results are important for understanding how stored lithium-ion batteries deteriorate and can help to guide battery design to maximize their shelf life
Comparison studies of epiphytic microbial communities on four macroalgae and their rocky substrates
Macroalgae and their rocky substrates both support diverse and abundant microbiota, performing essential ecological functions in marine ecosystem. However, the differences in the epiphytic microbial communities on macroalgae and rocky substrate are still poorly understood. In this study, the epiphytic microbial communities on four macroalgae (Corallina officinalis, Rhodomela confervoides, Sargassum thunbergii, and Ulva linza) and their rocky substrates from Weihai coast zone were characterized using high-throughput sequencing technology. The results showed that the alpha diversity indices were greater in rocky substrates than that in macroalgae. The microbial similarities among macroalgae and rocky substrate groups tended to decrease from the high taxonomic ranks to lower ranks, only 22.69% of the total amplicon sequence variants (ASVs) were shared between them. The functional analysis revealed that the microbiotas were mainly involved in metabolic activities. This study would provide the theoretical foundation for macroalgal cultivation and algal reef applications
Comparative analysis of the ribosomal DNA repeat unit (rDNA) of Perna viridis (Linnaeus, 1758) and Perna canaliculus (Gmelin, 1791)
Perna viridis and P. canaliculus are economically and ecologically important species of shellfish. In this study, the complete ribosomal DNA (rDNA) unit sequences of these species were determined for the first time. The gene order, 18S rRNA–internal transcribed spacer (ITS) 1–5.8S rRNA–ITS2–28S rRNA–intergenic spacer (IGS), was similar to that observed in other eukaryotes. The lengths of the P. viridis and P. canaliculus rDNA sequences ranged from 8,432 to 8,616 bp and from 7,597 to 7,610 bp, respectively, this variability was mainly attributable to the IGS region. The putative transcription termination site and initiation site were confirmed. Perna viridis and P. canaliculus rDNA contained two (length: 93 and 40 bp) and one (length: 131 bp) repeat motifs, respectively. Individual intra-species differences mainly involved the copy number of repeat units. In P. viridis, three cytosine-guanine (CpG) sites with sizes of 440, 1,075 and 537 bp were found to cover nearly the entire IGS sequence, whereas in P. canaliculus, two CpG islands with sizes of 361 and 484 bp were identified. The phylogenetic trees constructed with maximum likelihood and neighbour-joining methods and based on ITS sequences were identical and included three major clusters. Species of the same genus were easily clustered together
Stress induced by diffusion, curvature, and reversible electrochemical reaction in bilayer lithium-ion battery electrode plates
In this paper, a new reaction-diffusion model, coupling the reversible electrochemical reaction, Lithium (Li) diffusion, and bending, is proposed to investigate the curvature, neutral axis movement, and stress in bilayer electrode. Bending curvature and stress, for the first time, are analytically and numerically investigated relate to both the diffusion and the reversible electrochemical reaction. The results reveal that the reversible electrochemical reaction retards the lithiation process, leading to the slowing down of diffusion process. Two neutral axes exist in the active plate due to a gradient of mechanical properties during lithiation. The reaction makes the stress turn to compressive-state at the side surface of active plate, and more violent reaction aggravates this compressive stress during charging. Moreover, the reaction alleviates the compressive stress at interface, and limits the movement of the maximum tensile stress to the interface or the side surface of the active plate where the manufacturing defects are often present, thus eliminating the surface or interface fracture behaviors. The effect of the backward reaction is found to be ignorable under potentiostatic charging. Finally, the thickness ratio of current collector to active plate should be less than 0.3 on the premise of strength requirement. Current collector should be fabricated as softly as possible to mitigate the adverse stress. (C) 2017 Elsevier Ltd. All rights reserved
Comparative Analysis of the Ecological Succession of Microbial Communities on Two Artificial Reef Materials
Concrete and wood are commonly used to manufacture artificial reefs (ARs) worldwide for marine resource enhancement and habitat restoration. Although microbial biofilms play an important role in marine ecosystems, the microbial communities that colonize concrete and wooden ARs and their temporal succession have rarely been studied. In this study, the temporal succession of the microbial communities on concrete and wooden AR blocks and the driving factors were investigated. The composition of the microbial communities underwent successive shifts over time: among the six dominant phyla, the relative abundances of Proteobacteria, Cyanobacteria and Gracilibacteria significantly decreased in wood, as did that of Cyanobacteria in concrete. Operational taxonomic units (OTU) richness and Shannon index were significantly higher in concrete than in wood. Non-metric multidimensional scaling ordination placed the microbial communities in two distinct clusters corresponding to the two substrate materials. The macrobenthic compositions of concrete and wood were broadly similar and shifted over time, especially in the first five weeks. The Shannon index of the microbial communities in concrete and wood increased significantly with the organism coverage. The results provide fundamental data on microbial community succession during the initial deployment of ARs and contribute to understanding the ecological effects of ARs
Investigation on the physical and electrochemical properties of typical Ni-based alloys used for the bipolar plates of proton exchange membrane fuel cells
The phase, mechanical properties, corrosion resistance, hydrophobicity, and interface contact resistance of three typical Ni-based alloys (Hastelloy B, Hastelloy C-276, and Monel 400) and 304 stainless steels were experimentally studied to evaluate their service performances as bipolar plate materials of proton exchange membrane fuel cells. All four alloys exhibit single-phase face-centered cubic structure, high strength, good ductility, and high hardness. Hastelloy C-276 has the best ductility with an uniform elongation of 72.5% and highest hardness of 363.7 HV. Hastelloy B has the highest ultimate tensile strength of 913.6 MPa. The hydrophobicity of all four alloys is not good, although Monel 400 has the highest water contact angle of 84.2°. Hastelloy B, Hastelloy C-276, and 304 stainless steel exhibit unsatisfying corrosion resistance in a simulated acidic work environment of proton exchange membrane fuel cell (0.5 M H2SO4+2 ppm HF, 80 °C, H2) and high interface contact resistance. By contrast, Monel 400 demonstrates excellent corrosion resistance with a corrosion current density of 5.9 × 10−7 A cm−2 and a low interface contact resistance of 7.2 mΩ cm2 at 140 N/cm2. In terms of comprehensive performance, Monel 400 is the best uncoated material for the bipolar plates of proton exchange membrane fuel cells among typical Ni-based alloys
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