12 research outputs found

    Hydrochemical Denudation and Transient Carbon Dioxide Drawdown in the Highly Glacierized, Shrinking Koxkar Basin, China

    Get PDF
    This study considered solute fluxes and the transient CO2 drawdown process in the highly glacierized Koxkar basin in Central Eurasia, around 70.20% of which is covered by present-day ice. From 27 June to 30 September 2011, the total runoff depth was 671.70 mm, which yielded crustal solute fluxes of 213.65 ± 10.05 kg·(km2·d)−1 that accounted for 53.59% of the total solute flux of the river water. The solute fluxes derived directly from ice meltwater and precipitation were 70.02 ± 4.68 and 16.57 ± 1.13 kg·(km2·d)−1, respectively, which accounted for 17.57% and 4.16% of the total solute flux. The carbonation and hydrolysis of carbonate and feldspar minerals occurred because of the presence of H+, supplied by sulfide oxidation or CO2 drawdown. While the H+ yielded by sulfide oxidation was insufficient for hydrochemical reactions, atmospheric CO2 dissolved in the water generated H+ that drove follow-up reactions. The total transient drawdown of CO2 was 804.83 t C, which generated 39.61% of the total HCO3- and 24.68% of the river water solute. Transient drawdown of CO2 in the glacier region indicated that change of glacial area and volume could influence atmospheric CO2 concentration and be important in the long-term global CO2 cycle

    Reciprocal Regulation of Substance P and IL-12/IL-23 and the Associated Cytokines, IFNγ/IL-17: A Perspective on the Relevance of This Interaction to Multiple Sclerosis

    No full text
    The neuropeptide substance P (SP) exhibits cytokine-like properties and exerts different effects in autoimmune inflammation. Various immune cells express SP and its neurokinin-1 receptor (NK1R) isoforms. A role for SP has been demonstrated in a number of autoimmune conditions, including multiple sclerosis (MS). In this work, we studied the role of SP and NK1R in human immune cells with a focus on their relationship with IL-12/IL-23 family cytokines and the associated IFN-γ/IL-17. AIMS: (1) To determine the role of SP mediated effects on induction of various inflammatory cytokines in peripheral blood mononuclear cells (PBMC); (2) to investigate the expression of SP and its receptor in T cells and the effects of stimulation with IL-12 and IL-23. Quantitative real-time PCR, flow cytometry, ELISA, promoter studies on PBMC and primary T cells from healthy volunteers, and Jurkat cell line. Treatment with SP significantly increased the expression of IL-12/IL-23 subunit p40, IL-23 p19 and IL-12 p35 mRNA in human PBMC. Expression of NK1R and SP in T cells was upregulated by IL-23 but a trend was observed with IL-12. The IL-23 effect likely involves IL-17 production that additionally mediates IL-23 effects. Mutual interactions exist with SP enhancing the cytokines IL-23 and IL-12, and SP and NK1R expression being differentially but potentially synergistically regulated by these cytokines. These findings suggest a proinflammatory role for SP in autoimmune inflammation. We propose a model whereby immunocyte derived SP stimulates Th1 and Th17 autoreactive cells migrating to the central nervous system (CNS), enhances their crossing the blood brain barrier and perpetuates inflammation in the CNS by being released from damaged nerves and activating both resident glia and infiltrating immune cells. SP may be a therapeutic target in MS. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11481-015-9589-x) contains supplementary material, which is available to authorized users
    corecore