93 research outputs found
Long-term Change in Ablation Area of Tropical Glaciers by Landsat Data
AbstractGlacier meltwater is one of the main water resources in the capital of Bolivia. To understand current situation of glacier decline is crucial for better water resources management. This study investigated temporal and spatial glacial area during the past three decades between 1984 and 2014. Object glaciers were Tuni, Condoriri, and Huayna Potosi West Glacier with Landsat images. Glacier-covered area by Tuni, Condoriri, and Huayna Potosi West Glacier diminished by 70%, 52%, and 50%, individually from 1984 to 2014. Second, we estimated a front altitude and an equilibrium line altitude for each glacier. Front altitudes for three glaciers rise rapidly after 2000. Finally, we evaluated long-term change in ablation area for selected glaciers. Results showed that accumulation area ratio (AAR) increased with decrease in ablation area and this led to decrease in water resources
Resolvin E1は骨芽細胞におけるIL-17誘導性RANKL発現とRANKL誘導性破骨細胞分化を抑制することで破骨細胞形成および骨吸収を抑制する
【Background】 Resolvin E1 (RvE1) derived from the ω-3 polyunsaturated fatty acid eicosapentaenoic acid is known to be a potent pro-resolving lipid mediator that prevents chronic inflammation and osteoclastogenesis. We investigated the inhibitory effects of RvE1 on osteoclastogenesis and bone resorption to clarify its therapeutic potential for rheumatoid arthritis (RA).
【Methods】 Receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation was assessed with tartrate-resistant acid phosphatase staining. RANKL-induced bone resorption was assessed by the measurement of pit formation using calcium phosphate-labeled fluorescent polyanionic molecules in RAW264.7 cells as osteoclast precursors. The effects of RvE1 on the RANKL-induced mRNA expression of osteoclast-specific genes and transcriptional factors such as c-fos and nuclear factor of activated T cells c1 (NFATc1) in RAW264.7 cells were measured by quantitative real-time PCR. The distribution of NFATc1 induced by RANKL was evaluated by immunofluorescence staining in RAW264.7 cells. To analyze the mechanism of the inhibitory effect of RvE1 on osteoclastogenesis, we measured IL-17-induced RANKL mRNA expression in MC3T3-E1 osteoblast cells treated with RvE1 using quantitative real-time PCR and determined the level of prostaglandin E2 (PGE2) production by enzyme-linked immunosorbent assay.
【Results】 RvE1 significantly suppressed RANKL-induced osteoclast differentiation and bone resorption. RvE1 inhibited the RANKL-induced mRNA expression of osteoclast-specific genes along with the transcription factors NFATc1 and c-fos. Moreover, NFATc1 translocation from the cytoplasm to the nucleus of RAW264.7 cells was suppressed following RvE1 treatment. RvE1 also inhibited IL-17-induced RANKL mRNA expression and PGE2 production in MC3T3-E1 cells.
【Conclusion】 RvE1 inhibited osteoclastogenesis and bone resorption by suppressing RANKL-induced NFATc1 and c-fos expression in osteoclasts and IL-17- induced RANKL expression through the autocrine action of PGE2 in osteoblasts. Our data suggest RvE1 as a new therapeutic target of RA
Full Kinetic Analysis of Small-scale Magneto Plasma Sail in Magnetized Solar Wind
Abstract: Magneto Plasma Sail (MPS) is spacecraft propulsion that produces an artificial magnetosphere to block solar wind particles, and thus imparts momentum to accelerate a spacecraft. In the present study, we conducted three-dimensional particle-in-cell simulations on small-scale magnetospheres to investigate thrust characteristics of MPS, in which the magnetosphere is inflated by an additional plasma injection. As a result, we revealed that finite thrust generation and the increase in thrust is obtained in the small-scale magnetosphere even if the electron kinetics is taken into consideration. The thrust of MPS (0.58 mN @ magnetic moment M=1.3 10 7 Wb·m) becomes up to 97 times larger than that of the original magnetic sail (6.0 µN). It was also revealed that the thrust gain of MPS (thrust of MPS / (thrust of magnetic sail + thrust of plasma jet)) is more than unity (up to 5.2). However, the relation of trade-off between specific impulse, thrust-mass ratio and thrustpower ratio is revealed and the optimal design of the spacecraft and missions are required for the realization of MPS. Nomenclatur
Specialized Pro-Resolving Mediators Do Not Inhibit the Synthesis of Inflammatory Mediators Induced by Tumor Necrosis Factor-α in Synovial Fibroblasts
Background : Tumor necrosis factor (TNF)-α, a proinflammatory cytokine, is involved in the pathogenesis of rheumatoid arthritis (RA). The omega-3 unsaturated fatty acid-derived metabolites resolvin (Rv) D1, RvE1, and maresin-1 (MaR1) have been reported as anti-inflammatory lipid mediators and are known as specialized pro-resolving mediators (SPMs). In this study, we aimed to investigate the anti-inflammatory effects of SPMs on TNF-α-induced responses in synovial fibroblasts. Methods: We investigated the effects of SPMs on gene expression and/or production of cyclooxygenase-2 (COX-2), microsomal prostaglandin E synthase-1 (mPGES-1), interleukin (IL)-6, and matrix metalloproteinase (MMP)-3, which are involved in TNF-α-induced synovitis in RA or OA synovial fibroblasts, by quantitative real-time PCR. We also investigated the effects of SPMs on the mitogen-activated protein kinase (MAPK) signaling pathway by western blotting. Anti-inflammatory effects of SPMs were evaluated by applying SPMs to cultured synovial fibroblasts, followed by TNF-α stimulation. Results: The induction of COX-2, mPGES-1, IL-6, and MMP-3 by TNF-α in synovial fibroblasts was not suppressed by omega 3-derived SPMs regardless of their origin such as RA or OA. SPMs had no effect on lipid mediator receptor gene expression induce by TNF-α and did not inhibit the TNF-α-activated MAPK signaling pathway. The production of COX-2 and IL-6 protein was significantly decreased by p38 inhibitor. Conclusion: Despite reports on the anti-inflammatory effect of omega 3-derived SPMs, its anti-inflammatory effect on TNF-α-induced responses was not observed in synovial fibroblasts. The reason may be that SPMs have no suppressive effect on p38 activation, which plays an important role in the production of inflammatory cytokines in synovial fibroblasts
Leukocytapheresis for the treatment of acute exacerbation of idiopathic interstitial pneumonias : a pilot study
Objective : Idiopathic interstitial pneumonias (IIPs) are a group of heterogeneous diffuse parenchymal lung disorders of unknown etiology. An acute exacerbation (AE) is an acute respiratory deterioration that occurs in IIPs. The prognosis of AE of IIPs (AE-IIPs) is extremely severe ; however, no established therapies exist. We aimed to evaluate the efficacy of leukocytapheresis (LCAP) to treat patients with AE-IIPs. Patients and Methods : Six chronic IIPs patients who developed AE were enrolled in this study. We performed LCAP on days 2, 3, 9 and 10 in all six patients. All patients were also treated with high-dose corticosteroids and a continuous administration of low-molecular-weight heparin. We observed 30-day survival after the diagnosis of AE to evaluate the efficacy of LCAP. We also assessed oxygenation, high-resolution computed tomography (HRCT) findings, and certain chemical mediators in the peripheral blood. Results : Five of six patients survived more than 30 days. One patient died of progressive respiratory failure. Oxygenation and HRCT findings tended to improve in all survivors. The serum levels of lactate dehydrogenase, high mobility group box-1, and interleukin-18 were significantly decreased statistically post-LCAP. No severe adverse events occurred. Conclusion :We suggest that LCAP is a safe and effective therapy for treating patients with AE-IIPs
Resolvin E1 Inhibits Osteoclastogenesis and Bone Resorption by Suppressing IL-17-induced RANKL Expression in Osteoblasts and RANKL-induced Osteoclast Differentiation
【Background】 Resolvin E1 (RvE1) derived from the ω-3 polyunsaturated fatty acid eicosapentaenoic acid is known to be a potent pro-resolving lipid mediator that prevents chronic inflammation and osteoclastogenesis. We investigated the inhibitory effects of RvE1 on osteoclastogenesis and bone resorption to clarify its therapeutic potential for rheumatoid arthritis (RA). 【Methods】 Receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation was assessed with tartrate-resistant acid phosphatase staining. RANKL-induced bone resorption was assessed by the measurement of pit formation using calcium phosphate-labeled fluorescent polyanionic molecules in RAW264.7 cells as osteoclast precursors. The effects of RvE1 on the RANKL-induced mRNA expression of osteoclast-specific genes and transcriptional factors such as c-fos and nuclear factor of activated T cells c1 (NFATc1) in RAW264.7 cells were measured by quantitative real-time PCR. The distribution of NFATc1 induced by RANKL was evaluated by immunofluorescence staining in RAW264.7 cells. To analyze the mechanism of the inhibitory effect of RvE1 on osteoclastogenesis, we measured IL-17-induced RANKL mRNA expression in MC3T3-E1 osteoblast cells treated with RvE1 using quantitative real-time PCR and determined the level of prostaglandin E2 (PGE2) production by enzyme-linked immunosorbent assay. 【Results】 RvE1 significantly suppressed RANKL-induced osteoclast differentiation and bone resorption. RvE1 inhibited the RANKL-induced mRNA expression of osteoclast-specific genes along with the transcription factors NFATc1 and c-fos. Moreover, NFATc1 translocation from the cytoplasm to the nucleus of RAW264.7 cells was suppressed following RvE1 treatment. RvE1 also inhibited IL-17-induced RANKL mRNA expression and PGE2 production in MC3T3-E1 cells. 【Conclusion】 RvE1 inhibited osteoclastogenesis and bone resorption by suppressing RANKL-induced NFATc1 and c-fos expression in osteoclasts and IL-17-induced RANKL expression through the autocrine action of PGE2 in osteoblasts. Our data suggest RvE1 as a new therapeutic target of RA
Relationship between Oxidative Stress, Physical Activity, and Vitamin Intake in Patients with Asthma
Thread-Traction with a Sheath of Polypectomy Snare Facilitates Endoscopic Submucosal Dissection of Early Gastric Cancers
Although the thread-traction (TT) method has been found useful during endoscopic submucosal dissection (ESD) for early gastric cancers, the movement of the thread interferes with the movement of the endoscope, and the lesion can only be pulled to the mouth side. We have developed the novel TT method using a sheath of polypectomy snare (TTSPS). The TTSPS method enables free and independent movement of the thread and the endoscope and allows pulling the lesion towards the anal as well as oral side. The median dissection times, numbers of instances of arterial bleeding, and numbers of local injections into the submucosal layer were significantly lower for ESD with TTSPS than for conventional ESD. Countertraction ESD using the TTSPS method is straightforward, safe, easy, noninvasive, and cost effective, and it uses instruments readily available in most hospitals to enhance visualization of cutting lines. Therefore, the TTSPS method can be universally applied in conventional ESD
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