21 research outputs found

    Hydrogen Sulfide Protects against Chemical Hypoxia-Induced Cytotoxicity and Inflammation in HaCaT Cells through Inhibition of ROS/NF-κB/COX-2 Pathway

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    Hydrogen sulfide (H2S) has been shown to protect against oxidative stress injury and inflammation in various hypoxia-induced insult models. However, it remains unknown whether H2S protects human skin keratinocytes (HaCaT cells) against chemical hypoxia-induced damage. In the current study, HaCaT cells were treated with cobalt chloride (CoCl2), a well known hypoxia mimetic agent, to establish a chemical hypoxia-induced cell injury model. Our findings showed that pretreatment of HaCaT cells with NaHS (a donor of H2S) for 30 min before exposure to CoCl2 for 24 h significantly attenuated CoCl2-induced injuries and inflammatory responses, evidenced by increases in cell viability and GSH level and decreases in ROS generation and secretions of IL-1β, IL-6 and IL-8. In addition, pretreatment with NaHS markedly reduced CoCl2-induced COX-2 overexpression and PGE2 secretion as well as intranuclear NF-κB p65 subunit accumulation (the central step of NF-κB activation). Similar to the protective effect of H2S, both NS-398 (a selective COX-2 inhibitor) and PDTC (a selective NF-κB inhibitor) depressed not only CoCl2-induced cytotoxicity, but also the secretions of IL-1β, IL-6 and IL-8. Importantly, PDTC obviously attenuated overexpression of COX-2 induced by CoCl2. Notably, NAC, a ROS scavenger, conferred a similar protective effect of H2S against CoCl2-induced insults and inflammatory responses. Taken together, the findings of the present study have demonstrated for the first time that H2S protects HaCaT cells against CoCl2-induced injuries and inflammatory responses through inhibition of ROS-activated NF-κB/COX-2 pathway

    Enhanced Sunscreen Effects via Layer-By-Layer Self-Assembly of Chitosan/Sodium Alginate/Calcium Chloride/EHA

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    The sunscreen nanocapsules were successfully synthesized by the way of layer-by-layer self-assembly using charged droplets (prepared by emulsification of LAD-30, Tween-80 and EHA (2-Ethylhexyl-4-dimethylaminobenzoate)) as templates. Chitosan/sodium alginate/calcium chloride were selected as wall materials to wrap EHA. The emulsions with the ratio of Tween-80 to EHA (1:1) were stable. A stable NEI negative emulsion can be obtained when the ratio of Tween-80 and LAD-30 was 9:1. Chitosan solutions (50 kDa, 0.25 mg/mL) and sodium alginate solutions (0.5 mg/mL) were selected to prepare nanocapsules. The nanocapsules were characterized via some physico-chemical methods. Based on the synergistic effects of the electrostatic interaction between wall materials and emulsifiers, EHA was effectively encapsulated. DLS and TEM showed that the sunscreen nanocapsules were dispersed in a spherical shape with nano-size, with the increasing number of assembly layers, the size increased from 155 nm (NEI) to 189 nm (NEII) to 201 nm (NEIII) and 205 nm after solidification. The release studies in vitro showed sustained release behavior of the nanocapsules were observed with the increase of the number of deposition layers, implying a good coating effect. The sunscreen nanocapsules could control less than 50% the release of EHA after crosslinking of calcium chloride and sodium alginate, which also could effectively avoid the stimulation of the sun protection agent on the skin

    Method for measurement of wet gas in gas field by combining throttle flowmeter and vortex flowmeter

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    In order to solve the problem of single well without liquid phase measurement in Sulige Gas Field under the process mode of interwell series connection and wellhead wet gas measurement, a method of combining throttle flowmeter and vortex flowmeter to measure wet gas-liquid two-phase flow was proposed. The overall structure of flowmeter was simplified by integrating two kinds of flowmeter measuring tubes and adopting differential pressure static pressure, frequency and temperature integrated sensors. The indoor air-water two-phase flow experimental platform was used to test the measurement accuracy of the wet gas flowmeter. The results show that when the instantaneous liquid volume is 0.05-4 m3/h, the gas and liquid measurement errors of the combined wet gas flowmeter are within 5% and 20% respectively. The measurement accuracy of the wet gas flowmeter was tested at the wellhead of the gas well by using the separation metering device. The results show that the average error of gas and liquid phase measurement in the bubble exhaust well is less than 5% and 20% respectively, which can accurately reflect the liquid production law of the gas well and guide the optimization of the bubble discharge and filling system; the gas phase measurement error in the plunger gas lift well is less than 8%, and the liquid phase measurement error is large, but it can accurately reflect the liquid production characteristics of the plunger gas well, which could provide the basis for working condition diagnosis and production system optimization of plunger gas well

    The complete mitochondrial genome of Acrossocheilus yunnanensis (Teleostei: Cypriniformes: Cyprinidae) and its phylogenetic position

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    The complete mitochondrial genome of Acrossocheilus yunnanensis was determined in this study. It contained 13 protein-coding genes (PCGs), 22 tRNA, 2 rRNAs, and a control region with the base composition 31.47% A, 27.83% C, 24.65% T, and 16.05% G. Here we compared this newly determined mitogenome with another one from the same species reported before. The variable sites and the genetic distances between the two mitogenomes were 134 bp and 0.8%. Sixty-five variable sites occurred in the PCGs. The results from the phylogenetic analysis showed that the genus Acrossocheilus is not a monophyletic group and Acrossocheilus yunnanensis demonstrates a close relationship with Acrossocheilus monticola

    Shorter on-line warmup for sampled simulation of multi-threaded applications

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    Warmup is a crucial issue in sampled microarchitectural simulation to avoid performance bias by constructing accurate states for micro-architectural structures before each sampling unit. Not until very recently have researchers proposed Time-Based Sampling (TBS) for the sampled simulation of multi-threaded applications. However, warmup in TBS is challenging and complicated, because (i) full functional warmup in TBS causes very high overhead, limiting overall simulation speed; (ii) traditional adaptive functional warmup for sampling single-threaded applications cannot be readily applied to TBS; and (iii) checkpointing is inflexible (even invalid) due to the huge storage requirements and the variations across different runs for multi-threaded applications. In this work, we propose Shorter On-Line (SOL) warmup, which employs a two-stage strategy, using 'prime' warmup in the first stage, and an extended 'No-State-Loss (NSL)' method in the second stage. SOL is a single-pass, on-line warmup technique that addresses the warmup challenges posed in TBS in parallel simulators. SOL is highly accurate and efficient, providing a good trade-off between simulation accuracy and speed, and is easily deployed to different TBS techniques. For the PARSEC benchmarks on a simulated 8-core system, two state-of-the-art TBS techniques with SOL warmup provide a 7.2x and 37x simulation speedup over detailed simulation, respectively, compared to 3.1x and 4.5x under full warmup. SOL sacrifices only 0.3% in absolute execution time prediction accuracy on average

    Ploidy variation on gene differential expression in cowpea

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    ABSTRACT: This study investigated the differences in gene expression profiles of diploid and autotetraploid in cowpea, and provided theoretical basis for screening key genes of differential expression and ploidy breeding. The phenotypes and contents of chlorophyll, soluble sugar and soluble protein of diploid and autotetraploid of cowpea were compared and transcriptome sequencing was performed. The autotetraploid leaves of cowpea were thicker and darker green than diploid leaves, and the contents of chlorophyll, soluble sugar and soluble protein in leaves were higher. A total of 2678 differentially expressed genes (DEGs) were analyzed in the diploid and autotetraploid of cowpea. Among them, there were 421 genes with higher expression of tetraploid than diploid, and 2257 genes with lower expression of tetraploid than diploid. All 2678 DEGs were annotated into the Gene Ontology (GO) functional library. The DEGs were mainly concentrated in metabolism and cell composition. Kyoto Encyclopedia of Genes and Genomes (KEGG) Pathway analysis showed that cowpea diploid and autotetraploid have significant differences in flavonoid biosynthesis, degradation of other glycan, phenylpropane biosynthesis, starch sucrose metabolism, keratin, amber and wax biosynthesis, circadian rhythm and plant pathways

    Preparation and Characterization of Alkaline Anion Exchange Membrane for Fuel Cells Application

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    Alkaline anion exchange membrane (AAEM) plays an important role in the development of fuel cell. In this research, the electrostatic spinning technology was used to prepare AAEM. We use BC/TiO2 membrane as substrate by introduced quaternary ammonium groups to prepare BC/TiO2/CHPTAC (3-chloro-2-hydroxypropyl trimethyl ammonium chloride) composite membranes. The as-prepared composite membrane was characterized by XRD, SEM, XPS, and TG methods. It was found that BC/TiO2/CHPTAC (0.05 g) membrane exhibited high thermal stability and better comprehensive performance. The degree of substitution (DS), water uptake, and ion-exchange capacity (IEC) of BC/TiO2/CHPTAC membranes were investigated. The results showed that the DS, water uptake, and IEC of BC/TiO2/CHPTAC membrane were 1.16, 140%, and 1 mmol·g−1, respectively. We believe this composite membrane with excellent performances can promise many applications in fuel cells

    Hydrogen Sulfide Inhibits Abnormal Proliferation of Lymphocytes via AKT/GSK3� Signal Pathway in Systemic Lupus Erythematosus Patients

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    Background/Aim: The abnormal activation of the AKT/GSK3β signal pathway in lymphocytes from systemic lupus erythematosus (SLE) patients plays an important role in the pathogenesis of the disease. Recently Hydrogen sulfide (H2S) has been recognized as a crucial gaseous signaling molecule, involved in regulation of cell proliferation. However, the role of H2S in regulating the abnormal activation of lymphocytes from SLE patients has not been established. This study was conducted to investigate the effect of H2S on lymphocytes and to explore the mechanisms involved. Methods: The lymphocytes were isolated from SLE patients with or without renal disease and healthy controls. The cells were treated as indicated in each experiment. Cell viability was analyzed by CCK-8. Cell cycle distribution was determined by flow cytometry. Western blot was used to detect the expression of phosphorylated AKT (ser473), GSK3β (ser9) and CDK2, p27Kip1 and p21WAF1/CIP1. Results: Our findings showed that proliferation of lymphocytes was stimulated following treatment with NaHS (a H2S donor) at low NaHS concentrations (2mM). Similar results were observed using GYY4137, which is a slow-releasing H2S donor. Pretreatment of lymphocytes from SLE patients with NaHS at high concentrations prior to exposure to phytohemagglutinin (PHA) significantly attenuated proliferation, evidenced by decrease in cell viability and S phase distribution of cell cycle. Pretreatment with NaHS decreased PHA-induced expression of CDK2, phosphorylation levels of AKT (ser473) and GSK3β (ser9) and increased the expression of p27Kip1 and p21WAF1/CIP1. Moreover, pretreatment with NaHS blunted the stimulation of SLE lymphocyte proliferation by GSK3β inhibitor lithium chloride. Conclusion: These results demonstrate that H2S inhibits the abnormal activation of lymphocytes from SLE patients throuqh the AKT/GSK3β signal pathway
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