In the present study, triphlorethol-A, a phlorotannin, was isolated from Ecklonia cava and its antioxidant properties were investigated. Triphlorethol-A was found to scavenge intracellular reactive oxygen species (ROS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, and thus prevented lipid peroxidation. The radical scavenging activity of triphlorethol-A protected the Chinese hamster lung fibroblast (V79-4) cells exposed to hydrogen peroxide (H2O2) against cell death, via the activation of ERK protein. Furthermore, triphlorethol-A reduced the apoptotic cells formation induced by H2O2. Triphlorethol-A increased the activities of cellular antioxidant enzymes like, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). Hence, from the present study, it is suggestive that triphlorethol-A protects V79-4 cells against H2O2 damage by enhancing the cellular antioxidative activity.
Intracerebral hemorrhage (ICH) is a severe type of stroke causing neurological dysfunction with high mortality rate. Depression is one of the most common complications of ICH. In the present study, the effects of treadmill exercise on ICH-induced depressive symptoms in relation with apoptosis were investigated using rats. ICH rat model was induced by injection of collagenase into the hippocampus using stereotaxic instrument. Open field test for activity and forced swimming test for depressive symptoms were conducted. Apoptosis in the hippocampus was detected using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay, immunohistochemistry for caspase-3, and western blot for Bcl-2 and Bax. Western blot analysis for 5-hydroxy-tryptamine (5-HT, serotonin) and tryptophan hydroxylase (TPH) in the dorsal raphe was also conducted for biomarkers of depression. In the present results, immobility time was increased and climbing time was decreased by induction of ICH and treadmill exercise inhibited immobility time and increased climbing time in ICH rats. DNA fragmentation and caspase-3 expression in the hippocampal dentate gyrus were enhanced by induction of ICH and treadmill exercise suppressed ICH-induced DNA fragmentation and caspase-3 expression. Bax expression in the hippocampus was increased by induction of ICH and treadmill exercise inhibited Bax expression in the ICH rats. Expressions of 5-HT and TPH in the dorsal raphe were decreased by induction of ICH and treadmill exercise increased expressions of 5-HT and TPH in the ICH rats. In the present study, treadmill exercise ameliorated depressive symptoms through inhibiting apoptosis.
Rationale:Caudal epidural injection is one of the conventional treatments of chronic back pain. Even though spinal epidural hematoma after caudal epidural injection is rare but it can cause serious neurologic complication.Patient concerns:An 83-year-old woman taking cilostazol received caudal epidural steroid injection because of her chronic back pain. Six hours later, she experienced an acute hip pain which worsened with time.Diagnosis:Magnetic resonance image showed acute cord compression due to a spinal epidural hematoma at L2–S1 level with concomitant central canal compromise at L2/3, L3/4 level.Interventions:Emergency decompressive laminectomy and evacuation of the lumbar epidural hematoma were performed.Outcomes:All of her symptoms were resolved over the 72 hours following surgery.Lessons:Continuous vigilance after caudal epidural injection is important to prevent catastrophic neurologic deterioration with early detection and early treatment.
Experimental observation of the electron density variation in inductively coupled plasmas with the electron energy probability function (EEPFs) was performed at various gas pressures at two RF powers (25 W and 200 W). The measured EEPFs at high power discharges (200 W) showed a Maxwellian distribution, while evolution of the EEPFs from a bi-Maxwellian distribution to a Druyvesteyn-like distribution was observed at low RF powers (25 W) with increasing pressure. A discrepancy of the electron density variation between the two RF powers was observed. This difference is explained by the modified collisional loss and the Bohm velocity from the EEPF of the bi-Maxwellian distribution and the Druyvesteyn–like distribution.
We developed a high efficiency plasma source in an inductively coupled discharge using a passive resonant antenna, which has the advantage that it could be retro-fitted to existing reactors with minimal change to the reactor. At the resonance, the source has a larger total equivalent resistance that is 3-18 times larger than that at the non-resonance. As the resistance increases at the fixed RF power, the RF current decreases accordingly, which indicates that the power loss in the powered antenna including the impedance matching circuits is significantly reduced. The experimental result shows that the power transfer efficiency is improved by about 30%-70% and the plasma density at the resonance increases 2-8 times higher than that at the non-resonance. For analysis, three-winding transformer model is developed. The experimental results are consistent with the model.
In the manufacturing process for the lens system of a mobile phone camera, various types of assembly and manufacturing tolerances, such as tilt and decenter, should be appropriately allocated. Because these tolerances affect manufacturing cost and the expected optical performance, it is necessary to choose a systematic design methodology for determining optimal tolerances. In order to determine the tolerances that minimize production cost while satisfying the reliability constraints on important optical performance indices, we propose a tolerance design procedure for a lens system. A tolerance analysis is carried out using Latin hypercube sampling for evaluating the expected optical performance. The tolerance optimization is carried out using a function-based sequential approximate optimization technique that can reduce the computational burden and smooth numerical noise occurring in the optimization process. Using the proposed design approach, the optimal production cost was decreased by 28.3% compared to the initial cost while satisfying all the constraints on the expected optical performance. We believe that the tolerance analysis and design procedure presented in this study can be applied to the tolerance optimization of other systems.
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