108 research outputs found

    Zinc Remediation by Zero-Valent Iron and the Associated Isotope Fractionation: Batch Experiments

    Get PDF
    Zinc is a bio-essential micro nutrient which is essential to the health of humans and other organisms. However, high Zn concentrations, as has been observed in mining waste water and urban runoff, can be harmful. The major remediation methods used to reduce the mobility of Zn in groundwater flow systems include Zn precipitation and adsorption. Zero-valent Iron (ZVI) has been used as a remediation material in permeable reactive barriers (PRBs), and it can be used to reduce the concentration of Zn in waste water. Measurements of Zn isotope ratios, may provide information to trace Zn(II) migration and help define reaction mechanisms during remediation of Zn contamination using ZVI. Laboratory batch experiments, combined with traditional geochemical analysis, non-traditional stable isotope analysis and solid-phase analysis (XANES and EXAFS) were used to evaluate Zn removal mechanisms associated with ZVI in differing initial Zn-bearing solutions and with varying alkalinity concentrations. Decreasing concentrations of Zn were observed throughout all of the experiments. X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) analyses indicted the presence of Zn(II) on the solid phase with a coordination number of four, compared to a coordination number of six in the initial solutions. Models based on the measurements of EXAFS were used to assess the possible products on the solid phases. The results suggest that a combination of sorption and precipitation mechanisms dominated the removal of Zn for all of the aqueous solutions. The decline in dissolved Zn concentrations was accompanied by a decreasing value of δ66Zn in the experimental solutions, indicating preferential accumulation of 66Zn in the solid phase. The differences in dissolved Zn solutions and alkalinity did not significantly affect the extent of Zn isotope fractionation. The change in Zn concentration and δ66Zn can be fit with equilibrium fractionation models. The fractionation factors were similar for all batch experiments, reflecting the consistent change in coordination. The fractionation factors, which were calculated from the fitting process, cannot separate sorption-dominated and precipitation-dominated removal mechanism in these experiments

    Treatment Effects of Ischemic Stroke by Berberine, Baicalin, and Jasminoidin from Huang-Lian-Jie-Du-Decoction (HLJDD) Explored by an Integrated Metabolomics Approach

    Get PDF
    Berberine, baicalin, and jasminoidin were major active ingredients of Huang-Lian-Jie-Du-Decoction (HLJDD), a famous prescription of traditional Chinese medicine (TCM), which has been used for the treatment of ischemic stroke. The aim of the present study was to classify their roles in the treatment effects of ischemic stroke. A rat model of middle cerebral artery occlusion (MCAO) was constructed to mimic ischemic stroke and treatment effects of berberine, baicalin, and jasminoidin, and HLJDD was assessed by neurologic deficit scoring, infarct volume, histopathology, immunohistochemistry, biochemistry, quantitative real-time polymerase chain reaction (qRT-PCR), and Western blotting. In addition, the 1H NMR metabolomics approach was used to assess the metabolic profiles, which combined with correlation network analysis successfully revealed metabolic disorders in ischemic stroke concerning the treatment of the three principal compounds from HLJDD for the first time. The combined results suggested that berberine, baicalin, and jasminoidin are responsible for the effectiveness of HLJDD on the treatment of ischemic stroke by amelioration of abnormal metabolism and regulation of oxidative stress, neuron autophagy, and inflammatory response. This integrated metabolomics approach showed its potential in understanding the function of complex formulae and clarifying the role of its components in the overall treatment effects

    1H NMR-Based Metabolomics Reveals Refined-Huang-Lian-Jie-Du-Decoction (BBG) as a Potential Ischemic Stroke Treatment Drug With Efficacy and a Favorable Therapeutic Window

    Get PDF
    Huang-Lian-Jie-Du-Decoction (HLJDD) is a traditional Chinese medicine (TCM) used to treat ischemic stroke. However, the complexity of its chemical composition makes quality control difficult. Berberine, baicalin, and geniposide are the three main ingredients in HLJDD. Here, a formula of BBG comprised of berberine, baicalin, and geniposide, known as Refined-Huang-Lian-Jie-Du-Decoction, was investigated for its efficacy, therapeutic window, and mechanisms of action. BBG was assessed on two major types of ischemic stroke, cerebral ischemia-reperfusion (I/R) injury, and continuous ischemia injury, respectively. BBG showed efficacy comparable to HLJDD in the treatment of cerebral I/R injury within 5 h after injury initiation but did poorly in treating continuous ischemia injury. BBG exhibited neuroprotective effects on cerebral I/R injury by regaining the balance in energy metabolism, oxidative stress, amino acid metabolism, inflammation, and nucleic acid metabolism. These results suggested that BBG could be a good alternative to HLJDD, with high efficacy and a long therapeutic window, which shows great potential for drug development to treat stroke

    Airport pavement performance evaluation of pavement fog seal based on optimized test technology

    Get PDF
    Fog seal technology is widely used in airport asphalt pavement. The research on the performance and application of fog seal material is basically at the level of modified emulsified asphalt. The fog seal test method in the existing specification has defects. Three kinds of fog seal materials with different substrates were selected in this paper. Based on the characteristics of fog seal treatment and the relevant specifications of fog seal and airport pavement. Wet Track Abrasion Test (WTAT), Cantabro test, Water seepage test, and Pendulum instrument tester pavement friction coefficient test were improved. Test the pavement performance of different types of fog seals. The results show that the mass loss of material C was less than 10% after 200 and 400 cycles of wear. The improvement effect of material C on raveling resistance and impermeability was far better than that of materials A and B. The improvement of material C on the raveling resistance of the mixture could reach 50%. The immediate improvement effect on the impermeability was nearly 100%. The skid resistance performance of the three fog seal materials decreased after treatment. The decrease in material C was more significant than in materials A and B. In constructing material C, the dose of emery should be appropriately increased. It was advisable to not be less than 0.35 kg/m2. The fog seal layer improves pavement performance. It has reference significance for using fog seal technology to treat early airport pavement diseases

    A genome-wide association search for type 2 diabetes genes in African Americans.

    Get PDF
    African Americans are disproportionately affected by type 2 diabetes (T2DM) yet few studies have examined T2DM using genome-wide association approaches in this ethnicity. The aim of this study was to identify genes associated with T2DM in the African American population. We performed a Genome Wide Association Study (GWAS) using the Affymetrix 6.0 array in 965 African-American cases with T2DM and end-stage renal disease (T2DM-ESRD) and 1029 population-based controls. The most significant SNPs (n = 550 independent loci) were genotyped in a replication cohort and 122 SNPs (n = 98 independent loci) were further tested through genotyping three additional validation cohorts followed by meta-analysis in all five cohorts totaling 3,132 cases and 3,317 controls. Twelve SNPs had evidence of association in the GWAS (P<0.0071), were directionally consistent in the Replication cohort and were associated with T2DM in subjects without nephropathy (P<0.05). Meta-analysis in all cases and controls revealed a single SNP reaching genome-wide significance (P<2.5×10(-8)). SNP rs7560163 (P = 7.0×10(-9), OR (95% CI) = 0.75 (0.67-0.84)) is located intergenically between RND3 and RBM43. Four additional loci (rs7542900, rs4659485, rs2722769 and rs7107217) were associated with T2DM (P<0.05) and reached more nominal levels of significance (P<2.5×10(-5)) in the overall analysis and may represent novel loci that contribute to T2DM. We have identified novel T2DM-susceptibility variants in the African-American population. Notably, T2DM risk was associated with the major allele and implies an interesting genetic architecture in this population. These results suggest that multiple loci underlie T2DM susceptibility in the African-American population and that these loci are distinct from those identified in other ethnic populations

    Pentasaccharide Glycosides from the Tubers of Sweet Potato (Ipomoea batatas)

    No full text
    corecore