107 research outputs found
Essential role of liquid phase on melt-processed GdBCO single-grain superconductors
RE-Ba-Cu-O (RE denotes rare earth elements) single-grain superconductors have
garnered considerable attention owning to their ability to trap strong magnetic
field and self-stability for maglev. Here, we employed a modified melt-growth
method by adding liquid source (LS) to provide a liquid rich environment during
crystal growth. It further enables a significantly low maximum processing
temperature (Tmax) even approaching peritectic decomposition temperature. This
method was referred as the liquid source rich low Tmax (LS+LTmax) growth method
which combines the advantage of Top Seeded Infiltration Growth (TSIG) into Top
Seeded Melt-texture Growth (TSMG). The LS+LTmax method synergistically
regulates the perfect appearance and high superconducting performance in REBCO
single grains. The complementary role of liquid source and low Tmax on the
crystallization has been carefully investigated. Microstructure analysis
demonstrates that the LS+LTmax processed GdBCO single grains show clear
advantages of uniform distribution of RE3+ ions as well as RE211 particles. The
inhibition of Gd211 coarsening leads to improved pining properties. GdBCO
single-grain superconductors with diameter of 18 mm and 25 mm show maximum
trapped magnetic field of 0.746 T and 1.140 T at 77 K. These trapped fields are
significantly higher than those of conventional TSMG samples. Particularly, at
grain boundaries with reduced RE211 density superior flux pinning performance
has been observed. It indicates the existence of multiple pinning mechanisms at
these areas. The presented strategy provides essential LS+LTmax technology for
processing high performance single-grain superconductors with improved
reliability which is considered important for engineering applications
Investigate the genetic mechanisms of diabetic kidney disease complicated with inflammatory bowel disease through data mining and bioinformatic analysis
BackgroundPatients with diabetic kidney disease (DKD) often have gastrointestinal dysfunction such as inflammatory bowel disease (IBD). This study aims to investigate the genetic mechanism leading to IBD in DKD patients through data mining and bioinformatics analysis.MethodsThe disease-related genes of DKD and IBD were searched from the five databases of OMIM, GeneCards, PharmGkb, TTD, and DrugBank, and the intersection part of the two diseases were taken to obtain the risk genes of DKD complicated with IBD. A proteināprotein interaction (PPI) network analysis was performed on risk genes, and three topological parameters of degree, betweenness, and closeness of nodes in the network were used to identify key risk genes. Finally, Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were performed on the risk genes to explore the related mechanism of DKD merging IBD.ResultsThis study identified 495 risk genes for DKD complicated with IBD. After constructing a proteināprotein interaction network and screening for three times, six key risk genes were obtained, including matrix metalloproteinase 2 (MMP2), hepatocyte growth factor (HGF), fibroblast growth factor 2 (FGF2), interleukin (IL)-18, IL-13, and CāC motif chemokine ligand 5 (CCL5). Based on GO enrichment analysis, we found that DKD genes complicated with IBD were associated with 3,646 biological processes such as inflammatory response regulation, 121 cellular components such as cytoplasmic vesicles, and 276 molecular functions such as G-protein-coupled receptor binding. Based on KEGG enrichment analysis, we found that the risk genes of DKD combined with IBD were associated with 181 pathways, such as the PI3K-Akt signaling pathway, advanced glycation end productāreceptor for AGE (AGE-RAGE) signaling pathway and hypoxia-inducible factor (HIF)-1 signaling pathway.ConclusionThere is a genetic mechanism for the complication of IBD in patients with CKD. Oxidative stress, chronic inflammatory response, and immune dysfunction were possible mechanisms for DKD complicated with IBD
Altered microRNA expression profile with miR-146a upregulation in CD4+ T cells from patients with rheumatoid arthritis
Introduction: Increasing evidence indicates that microRNAs (miRNAs) play a critical role in the pathogenesis of inflammatory diseases. The aim of the study was to investigate the expression pattern and function of miRNAs in CD4 + T cells from patients with rheumatoid arthritis (RA).Methods: The expression profile of miRNAs in CD4 + T cells from synovial fluid (SF) and peripheral blood of 33 RA patients was determined by microarray assay and validated by qRT-PCR analysis. The correlation between altered expression of miRNAs and cytokine levels was determined by linear regression analysis. The role of miR-146a overexpression in regulating T cell apoptosis was evaluated by flow cytometry. A genome-wide gene expression analysis was further performed to identify miR-146a-regulated genes in T cells.Results: miRNA expression profile analysis revealed that miR-146a expression was significantly upregulated while miR-363 and miR-498 were downregulated in CD4 + T cells of RA patients. The level of miR-146a expression was positively correlated with levels of tumor necrosis factor-alpha (TNF-Ī±), and in vitro studies showed TNF-Ī± upregulated miR-146a expression in T cells. Moreover, miR-146a overexpression was found to suppress Jurkat T cell apoptosis. Finally, transcriptome analysis of miR-146a overexpression in T cells identified Fas associated factor 1 (FAF1) as a miR-146a-regulated gene, which was critically involved in modulating T cell apoptosis.Conclusions: We have detected increased miR-146a in CD4 + T cells of RA patients and its close correlation with TNF-Ī± levels. Our findings that miR-146a overexpression suppresses T cell apoptosis indicate a role of miR-146a in RA pathogenesis and provide potential novel therapeutic targets. Ā© 2010 Li et al.; licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.published_or_final_versio
Ras-induced Epigenetic Inactivation of the RRAD ( Ras-related Associated with Diabetes) Gene Promotes Glucose Uptake in a Human Ovarian Cancer Model
Background: Increased glucose uptake is essential for carcinogenesis. Results: Ras(V12)-induced epigenetic inactivation of RRAD promotes glucose uptake and tumor formation. Conclusion: RRAD might act as a functional tumor suppressor by inhibiting glucose uptake. Significance: Down-regulation of RRAD in tumor tissues might be associated with the Warburg effect. RRAD (Ras-related associated with diabetes) is a small Ras-related GTPase that is frequently inactivated by DNA methylation of the CpG island in its promoter region in cancer tissues. However, the role of the methylation-induced RRAD inactivation in tumorigenesis remains unclear. In this study, the Ras-regulated transcriptome and epigenome were profiled by comparing T29H (a Ras(V12)-transformed human ovarian epithelial cell line) with T29 (an immortalized but non-transformed cell line) through reduced representation bisulfite sequencing and digital gene expression. We found that Ras(V12)-mediated oncogenic transformation was accompanied by RRAD promoter hypermethylation and a concomitant loss of RRAD expression. In addition, we found that the RRAD promoter was hypermethylated, and its transcription was reduced in ovarian cancer versus normal ovarian tissues. Treatment with the DNA methyltransferase inhibitor 5-aza-2-deoxycytidine resulted in demethylation in the RRAD promoter and restored RRAD expression in T29H cells. Additionally, treatment with farnesyltransferase inhibitor FTI277 resulted in restored RRAD expression and inhibited DNA methytransferase expression and activity in T29H cells. By employing knockdown and overexpression techniques in T29 and T29H, respectively, we found that RRAD inhibited glucose uptake and lactate production by repressing the expression of glucose transporters. Finally, RRAD overexpression in T29H cells inhibited tumor formation in nude mice, suggesting that RRAD is a tumor suppressor gene. Our results indicate that Ras(V12)-mediated oncogenic transformation induces RRAD epigenetic inactivation, which in turn promotes glucose uptake and may contribute to ovarian cancer tumorigenesis
Chemical composition, antioxidant and antitumor activities of sub-fractions of wild and cultivated Pleurotus ferulae ethanol extracts
Pleurotus ferulae is an edible and medicinal mushroom with various bioactivities. Here, the ethanol extracts of wild and cultivated P. ferulae (PFEE-W and PFEE-C) and their subfractions including petroleum ether (Pe-W/Pe-C), ethyl acetate (Ea-W/Ea-C) and n-butanol (Ba-W/Ba-C) were prepared to evaluate their antioxidant and antitumor activities. Both PFEE-W and PFEE-C show the antioxidant activity and PFEE-W is stronger than PFEE-C. The antioxidant activities of their subfractions are in the following order: Ea > Ba > Pe. Moreover, PFEE-W and PFEE-C significantly inhibit the proliferation of murine melanoma B16 cells, human esophageal cancer Eca-109 cells, human gastric cancer BGC823 cells and human cervical cancer HeLa cells through induction of apoptosis, which partially mediated by reactive oxygen species. The antitumor activities of their subfractions are in the following order: Ea ā„ Pe > Ba. Pe-W shows higher antitumor activity compared with Pe-C, which might be correlated with the difference of their components identified by gas chromatography-mass spectrometry. These results suggest that both wild and cultivated P. ferulae have antioxidant and antitumor activities, and cultivated P. ferulae could be used to replace wild one in some functions
Beam test of a 180 nm CMOS Pixel Sensor for the CEPC vertex detector
The proposed Circular Electron Positron Collider (CEPC) imposes new
challenges for the vertex detector in terms of pixel size and material budget.
A Monolithic Active Pixel Sensor (MAPS) prototype called TaichuPix, based on a
column drain readout architecture, has been developed to address the need for
high spatial resolution. In order to evaluate the performance of the
TaichuPix-3 chips, a beam test was carried out at DESY II TB21 in December
2022. Meanwhile, the Data Acquisition (DAQ) for a muti-plane configuration was
tested during the beam test. This work presents the characterization of the
TaichuPix-3 chips with two different processes, including cluster size, spatial
resolution, and detection efficiency. The analysis results indicate the spatial
resolution better than 5 and the detection efficiency exceeds 99.5 %
for both TaichuPix-3 chips with the two different processes
Proton pump inhibitors may enhance the risk of digestive diseases by regulating intestinal microbiota
Proton pump inhibitors (PPIs) are the most used acid-inhibitory drugs, with a wide range of applications in the treatment of various digestive diseases. However, recently, there has been a growing number of digestive complications linked to PPIs, and several studies have indicated that the intestinal flora play an important role in these complications. Therefore, developing a greater understanding of the role of the gut microbiota in PPI-related digestive diseases is essential. Here, we summarize the current research on the correlation between PPI-related digestive disorders and intestinal flora and establish the altered strains and possible pathogenic mechanisms of the different diseases. We aimed to provide a theoretical basis and reference for the future treatment and prevention of PPI-related digestive complications based on the regulation of the intestinal microbiota
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