131 research outputs found
Edaravone Improves the Post-traumatic Brain Injury Dysfunction in Learning and Memory by Modulating Nrf2/ARE Signal Pathway
OBJECTIVES: To investigate the molecular mechanism of edaravone (EDA) in improving the post-traumatic brain injury (TBI) dysfunction in learning and memory.
METHODS: In vitro and in vivo TBI models were established using hydrogen peroxide (H2O2) treatment for hippocampal nerve stem cells (NSCs) and surgery for rats, followed by EDA treatment. WST 1 measurement, methylthiazol tetrazolium assay, and flow cytometry were performed to determine the activity, proliferation, and apoptosis of NSCs, and malondialdehyde (MDA), lactic dehydrogenase (LDH), and reactive oxygen species (ROS) detection kits were used to analyze the oxides in NSCs.
RESULTS: Following EDA pretreatment, NSCs presented with promising resistance to H2O2-induced oxidative stress, whereas NSCs manifested significant increases in activity and proliferation and a decrease in apoptosis. Meanwhile, for NSCs, EDA pretreatment reduced the levels of MDA, LDH, and ROS, with a significant upregulation of Nrf2/antioxidant response element (ARE) signaling pathway, whereas for EDA-treated TBI rats, a significant reduction was observed in the trauma area and injury to the hippocampus, with improvement in memory and learning performance and upregulation of Nrf2/ARE signaling pathway.
CONCLUSIONS: EDA, by regulating the activity of Nrf2/ARE signal pathway, can improve the TBI-induced injury to NSCs and learning and memory dysfunction in rats.
 
Water Pipeline Leakage Detection Based on Machine Learning and Wireless Sensor Networks
The detection of water pipeline leakage is important to ensure that water supply networks can operate safely and conserve water resources. To address the lack of intelligent and the low efficiency of conventional leakage detection methods, this paper designs a leakage detection method based on machine learning and wireless sensor networks (WSNs). The system employs wireless sensors installed on pipelines to collect data and utilizes the 4G network to perform remote data transmission. A leakage triggered networking method is proposed to reduce the wireless sensor network’s energy consumption and prolong the system life cycle effectively. To enhance the precision and intelligence of leakage detection, we propose a leakage identification method that employs the intrinsic mode function, approximate entropy, and principal component analysis to construct a signal feature set and that uses a support vector machine (SVM) as a classifier to perform leakage detection. Simulation analysis and experimental results indicate that the proposed leakage identification method can effectively identify the water pipeline leakage and has lower energy consumption than the networking methods used in conventional wireless sensor networks
A Bionic Data-driven Approach for Long-distance Underwater Navigation with Anomaly Resistance
Various animals exhibit accurate navigation using environment cues. The
Earth's magnetic field has been proved a reliable information source in
long-distance fauna migration. Inspired by animal navigation, this work
proposes a bionic and data-driven approach for long-distance underwater
navigation. The proposed approach uses measured geomagnetic data for the
navigation, and requires no GPS systems or geographical maps. Particularly, we
construct and train a Temporal Attention-based Long Short-Term Memory (TA-LSTM)
network to predict the heading angle during the navigation. To mitigate the
impact of geomagnetic anomalies, we develop the mechanism to detect and
quantify the anomalies based on Maximum Likelihood Estimation. We integrate the
developed mechanism with the TA-LSTM, and calibrate the predicted heading
angles to gain resistance against geomagnetic anomalies. Using the retrieved
data from the WMM model, we conduct numerical simulations with diversified
navigation conditions to test our approach. The simulation results demonstrate
a resilience navigation against geomagnetic anomalies by our approach, along
with precision and stability of the underwater navigation in single and
multiple destination missions
Au@h-Al2O3 Analogic Yolk–Shell Nanocatalyst for Highly Selective Synthesis of Biomass-Derived D-xylonic Acid via Regulation of Structure Effects
Selective oxidation of biomass-based monosaccharides into value-added sugar acids is highly desired, but limited success of producing D-xylonic acid has been achieved. Herein, we report an efficient catalyst system, viz., Au nanoparticles anchored on the inner walls of hollow Al2O3 nanospheres (Au@h- Al2O3), which could catalyze the selective oxidation of D-xylose into D-xylonic acid under base-free conditions. The mesoporous Al2O3 shell as the adsorbent first adsorbed D-xylose. Then, the interface of Au nanoparticles and Al2O3 as active sites spontaneously dissociated O2, and the exposed Au nanoparticle surface as the catalytic site drove the transformation. With this catalyst system, the valuable D-xylonic acid was produced with excellent yields in the aerobic oxidation of D-xylose. Extensive investigation showed that Au@h- Al2O3 is an efficient catalyst with high stability and recyclability
Effects of Different Lights on Seed Germination, Total Flavonoids Synthesis, and Related Enzyme Activities of Toona sinensis Seedlings
In order to explore the effects of different lights on seed germination, total flavonoids synthesis, and related enzyme activities of Toona sinensis seedlings, LED were applied to the seeds and seedlings of Toona sinensis. The experimental materials were ‘Hongyou Toona sinensis’. White light (CK), blue light (B), red and blue light 2:1 (R2B1), red and blue light 1:1 (R1B1), red and blue light 1:2 (R1B2), red light (R) were used for 15 days respectively, and the seed germination, total flavonoid synthesis and related enzyme activities in seedlings were measured. The results showed that compared to the control group (CK), the red light dominated illumination (R, R1B1, R2B1) promoted the seeds germination, and the dry and fresh weight of the whole plant treated with light (R2B1) increased by 55.06% and 82.86% respectively, which were the highest among all the treatments. Compared with CK and R, other light treatments significantly increased the total flavonoid content in Toona sinensis seedlings (P<0.05). Treatment B was significantly higher than other groups, and the activities of phenylalanine ammonia lyase (PAL), chalcone synthase (CHS), and chalcone isomerase (CHI) were also significantly increased (P<0.05), which showed a significant positive correlation with the changes in total flavonoid. Therefore, the germination of Toona sinensis seeds can be facilitated by the treatment of R2B1, and a significant enhancement in total flavonoid synthesis can be achieved by the treatment of B for Toona sinensis seedlings, effectively promoting the activities of PAL, CHS, and CHI enzymes
Analysis of the vp2 gene sequence of a new mutated mink enteritis parvovirus strain in PR China
<p>Abstract</p> <p>Background</p> <p>Mink enteritis virus (MEV) causes a highly contagious viral disease of mink with a worldwide distribution. MEV has a linear, single-stranded, negative-sense DNA with a genome length of approximately 5,000 bp. The VP2 protein is the major structural protein of the parvovirus encoded by the <it>vp</it>2 gene. VP2 is highly antigenic and plays important roles in determining viral host ranges and tissue tropisms. This study describes the bionomics and <it>vp</it>2 gene analysis of a mutated strain, MEV-DL, which was isolated recently in China and outlines its homologous relationships with other selected strains registered in Genbank.</p> <p>Results</p> <p>The MEV-DL strain can infect F81 cells with cytopathic effects. Pig erythrocytes were agglutinated by the MEV-DL strain. The generation of MEV-DL in F81 cells could infect mink within three months and cause a disease that was similar to that caused by wild-type MEV. A comparative analysis of the <it>vp</it>2 gene nucleotide (nt) sequence of MEV-DL showed that this was more than 99% homologous with other mink enteritis parvoviruses in Genbank. However, the nucleotide residues at positions 1,065 and 1,238 in the MEV-DL strain of the <it>vp</it>2 gene differed from those of all the other MEV strains described previously. It is noteworthy that the mutation at the nucleotide residues position 1,238 led to Asp/Gly replacement. This may lead to structural changes. A phylogenetic tree and sequence distance table were obtained, which showed that the MEV-DL and ZYL-1 strains had the closest inheritance distance.</p> <p>Conclusions</p> <p>A new variation of the <it>vp</it>2 gene exists in the MEV-DL strain, which may lead to structural changes of the VP2 protein. Phylogenetic analysis showed that MEV-DL may originate from the ZYL-1 strain in DaLian.</p
Crystal Structure of the C-Terminal Cytoplasmic Domain of Non-Structural Protein 4 from Mouse Hepatitis Virus A59
BACKGROUND:The replication of coronaviruses takes place on cytoplasmic double membrane vesicles (DMVs) originating in the endoplasmic reticulum (ER). Three trans-membrane non-structural proteins, nsp3, nsp4 and nsp6, are understood to be membrane anchors of the coronavirus replication complex. Nsp4 is localized to the ER membrane when expressed alone but is recruited into the replication complex in infected cells. It is revealed to contain four trans-membrane regions and its N- and C-termini are exposed to the cytosol. METHODOLOGY/PRINCIPAL FINDINGS:We have determined the crystal structures of the C-terminal hydrophilic domain of nsp4 (nsp4C) from MHV strain A59 and a C425S site-directed mutant. The highly conserved 89 amino acid region from T408 to Q496 is shown to possess a new fold. The wild-type (WT) structure features two monomers linked by a Cys425-Cys425 disulfide bond in one asymmetric unit. The monomers are arranged with their N- and C-termini in opposite orientations to form an "open" conformation. Mutation of Cys425 to Ser did not affect the monomer structure, although the mutant dimer adopts strikingly different conformations by crystal packing, with the cross-linked C-termini and parallel N-termini of two monomers forming a "closed" conformation. The WT nsp4C exists as a dimer in solution and can dissociate easily into monomers in a reducing environment. CONCLUSIONS/SIGNIFICANCE:As nsp4C is exposed in the reducing cytosol, the monomer of nsp4C should be physiological. This structure may serve as a basis for further functional studies of nsp4
Arterial stiffness in subclinical atherosclerosis quantified with ultrafast pulse wave velocity measurements: a comparison with a healthy population using propensity score matching
Purpose This study aimed to evaluate changes in ultrafast pulse wave velocity (ufPWV) in individuals with arterial stiffness and subclinical atherosclerosis (subAS), and to provide cutoff values. Methods This retrospective study recruited 231 participants, including 67 patients with subAS. The pulse wave velocity was measured at the beginning and end of systole (PWV-BS and PWVES, respectively) using ultrafast ultrasonography to assess arterial stiffness. The right and left common carotid arteries were measured separately, and laboratory metabolic parameters were also collected. Participants were balanced between groups using propensity score matching (PSM) at a 1:1 ratio, adjusting for age, sex, and waist-to-hip ratio as potential confounders. Cutoff values of ufPWV for monitoring subAS were determined via receiver operating characteristic (ROC) curve analysis. Results PWV-ES, unlike PWV-BS, was higher in the subAS subgroup than in the subAS-free group after PSM (all P0.05). Conclusion PWV-ES measured using ultrafast ultrasonography was significantly higher in individuals with subAS than in those without. Specific PWV-ES cutoff values showed potential for predicting an increased risk of subAS
Spry1 Is Expressed in Hemangioblasts and Negatively Regulates Primitive Hematopoiesis and Endothelial Cell Function
Development of the hematopoietic and endothelial lineages derives from a common mesodermal precursor, the Flk1(+) hemangioblast. However, the signaling pathways that regulate the development of hematopoietic and endothelial cells from this common progenitor cell remains incompletely understood. Using mouse models with a conditional Spry1 transgene, and a Spry1 knockout mouse, we investigated the role of Spry1 in the development of the endothelial and hematopoietic lineages during development.Quantitative RT-PCR analysis demonstrates that Spry1, Spry2, and Spry4 are expressed in Flk1(+) hemangioblasts in vivo, and decline significantly in c-Kit(+) and CD41(+) hematopoietic progenitors, while expression is maintained in developing endothelial cells. Tie2-Cre-mediated over-expression of Spry1 results in embryonic lethality. At E9.5 Spry1;Tie2-Cre embryos show near normal endothelial cell development and vessel patterning but have reduced hematopoiesis. FACS analysis shows a reduction of primitive hematopoietic progenitors and erythroblastic cells in Spry1;Tie2-Cre embryos compared to controls. Colony forming assays confirm the hematopoietic defects in Spry1;Tie2-Cre transgenic embryos. Immunostaining shows a significant reduction of CD41 or CD71 and dpERK co-stained cells in Spry1;Tie2-Cre embryos compared to controls, whereas the number of VEC(+) and dpERK co-stained cells is comparable. Compared to controls, Spry1;Tie2-Cre embryos also show a decrease in proliferation and an increase in apoptosis. Furthermore, loss of Spry1 results in an increase of CD41(+) and CD71(+) cells at E9.5 compared with controls.These data indicate that primitive hematopoietic cells derive from Tie2-expressing hemangioblasts and that Spry1 over expression inhibits primitive hematopoietic progenitor and erythroblastic cell development and expansion while having no obvious effect on endothelial cell development
- …