Quercetin is a flavonoid that has roles in both cytoprotection and cytotoxicity. The relation of queretin's cytoprotective and cytotoxic effects are unknown. Quercetin has been shown to induce ...expression of hypoxia-inducible factor, a protein that is known to regulate transcription of the erythropoietin (EPO) gene, and EPO is known to have a cytoprotective effect. This study used HepG2 cells to assess whether the cell-protective and/or cytotoxic roles of quercetin are mediated by promotion of EPO production. Increases in the levels of HIF-1α protein and EPO mRNA were quercetin concentration-dependent, with significant increases observed from 10 μM quercetin. Silencing of EPO expression by si-EPO RNA attenuated quercetin-induced cytoprotection against hydrogen peroxide toxicity. Cytotoxicity, evidenced by the induction of apoptosis, was significantly increased by exposure to 50 μM quercetin. Specifically, the levels of cleaved caspase-3 and Bax and the rate of cell death increased, and the level of Bcl-2 decreased, in cells treated with 50 μM quercetin. In contrast, exposure to 10 μM quercetin attenuated cisplatin-induced apoptosis. However, quercetin's ability to protect cells from cisplatin-induced apoptosis was eliminated when EPO expression was silenced using si-EPO RNA. Together, these results suggested that quercetin's cytoprotective effects in HepG2 cells are mediated via EPO production.
•Quercetin has both cytoprotective and cytotoxic effects on HepG2 cell.•Quercetin's cytoprotective effects in HepG2 cells are mediated via EPO production.•Quercetin's cytotoxic effects as apoptosis in HepG2 cells are not affect by EPO.
PurposeTo compare the degree of medial meniscal extrusion (MME) between knees with medial meniscus posterior root tear (MMPRT) and degenerative tears of the medial meniscus using ultrasonography (US) ...in different limb positions and to identify the findings characteristic of MMPRT.MethodsThe study group comprised 25 subjects with MMPRT (group RT), 25 subjects with degenerative medial meniscal tears (group D), and 25 knees with no abnormalities of the medial meniscus (MM) on magnetic resonance imaging (MRI) (group C) whose age was ≥40 years. MME was evaluated using US in the supine, figure-4, feet-dangling, and standing positions. The MME was evaluated by the actual measurement values and the relative values to the MME in the supine position. The differences in the MME among the 3 groups in each limb position were analyzed using one-way analysis of variance. P < .05 was considered significant.ResultsThe actual MME values were largest in group RT in all 4 limb positions. When changing the limb position from the supine to the figure-4, the actual MME increased from 3.8 ± 0.8 mm to 5.5 ± 1.3 mm in group RT, whereas it decreased from 3.4 ± 1.1 mm to 1.8 ± 1.2 mm in group D, showing the most significant difference in MME of the figure-4 position between the 2 groups (P < .001). In group RT, 88% of knees had the maximum MME in the figure-4 position. In group D, 60% of knees had the maximum MME in the standing position and only 2 knees (8%) had the maximum MME in the figure-4 position.ConclusionsThe increase in MME from the supine to the figure-4 position was a characteristic finding of MMPRT but not degenerative tears.Level of EvidenceLevel III, case-control study.
The rail track is one of the most important structures for maintenance among railway structures. The rail track is subjected to repeated loads by the wheels directly, causing track deviation. Track ...irregurality causes unsafety and uncomfortable running of train. There is a method of measuring orbital deviation. By installing a recursive target for image measurement on the rail of the train, the coordinates of the center of gravity are measured with a digital camera. Track distortion caused by repeated train running is measured. However, since the train repeatedly travels, deposits are attached due to external environmental factors, and the target becomes black. In this study, the attached matter was analyzed and the kind of attached matter was confirmed. By analyzing the attached matter, various materials are found, and it is possible to infer a blackened state. Knowing the actual condition of the adhering matter enables countermeasures and prevention, leading to a reduction in maintenance work.
Techniques have been developed for measuring orbital deviation by image measurement. In this method, the trajectory distortion is measured by measuring the coordinates of the center of gravity of the ...circle with a digital camera. However, due to the repeated train running, the surface of the recursive target for measurement becomes black due to dirt, and the position of the center of gravity of the circle cannot be accurately measured on the image. Dirt due to the deposits is an important issue, and a technique for protecting the surface of the target from dirt is desired. In this study, we develop a target antifouling sheet using a metamaterial technology that imitates a snail shell and has an oil-repellent effect and verifies the effect.
Anti-fouling Evaluation System Using Reflected Light Mamiya, Tomohiro; Nishioka, Sotaro; Nobuhara, Ryota ...
Journal of Photopolymer Science and Technology,
2020/12/15, Letnik:
33, Številka:
6
Journal Article
Odprti dostop
In recent years, methods for evaluating various dirt such as air and water have been developed. Techniques have been developed for measuring orbital deviation by image measurement. In this method, ...the trajectory distortion is measured by measuring the coordinates of the center of gravity of the circle with a digital camera. However, due to repeated train running, the surface of the recursive target for measurement becomes black due to dirt, and the position of the center of gravity of the circle cannot be accurately measured on the image. When the target becomes black, the position of the center of gravity of the circle cannot be accurately measured on the image, so cleaning is required about twice a month. Dirt due to the deposits is an important issue, and a technique for protecting the surface of the target from dirt is desired. By evaluating the contamination of the target numerically, it is possible to more efficiently develop a better arrangement position and an antifouling technology. The developed dirt evaluation device digitizes the degree of dirt using a photo sensor and numerically evaluates the degree of dirt. This paper describes the principle, measurement method, and actual evaluation results of the developed contamination evaluation device.
Carbon fiber reinforced polymer (CFRP), plates bonding repair method is one of the simple repair methods for cracked steel structures. In this study, the influence of width of CFRP plates on bending ...fatigue life of out-of-plane gusset joint strengthened with CFRP plates was investigated from the experimental and numerical point of view. In the bending fatigue test of cracked out-of-plane gusset joint strengthened with CFRP plates, the effect of width of CFRP plates on crack growth life was clarified experimentally. Namely, it was revealed that the crack growth life becomes larger with increasing the width of CFRP plates. In the numerical approach, the stress intensity factor (
SIF
) at the surface point of a semi-elliptical surface crack was estimated based on the linear fracture mechanics. Furthermore, the extended fatigue life of cracked out-of-plane gusset joint strengthened with CFRP plates was evaluated by using the estimated
SIF
at the surface point and the empirical formula of the aspect ratio of semi-elliptical crack. As the results of numerical analysis, the estimated fatigue life of the specimen strengthened with CFRP plates showed the good agreement with the test results.
Techniques have been developed for measuring orbital deviation by image measurement. In this method, the trajectory distortion is measured by measuring the coordinates of the center of gravity of the ...circle with a digital camera. However, due to the repeated train running, the surface of the recursive target for measurement becomes black due to dirt, and the position of the center of gravity of the circle cannot be accurately measured on the image. When the target becomes black, the center of gravity of the circle cannot be accurately measured on the image, so currently it needs to be cleaned about twice a month. Dirt due to the deposits is an important issue, and a technique for protecting the surface of the target from dirt is desired. In this study, we evaluated the surface effect of hydrophilic, water-repellent and metamaterial sheets on water and muddy water. Prevention is possible due to the oil repellency and dustproof effect, which leads to a reduction in maintenance work. In the near future, it aims to develop an oil-repellent and dust-proof metamaterial sheet for maintenance-free technology.
Fatigue tests and numerical analyses were carried out in order to investigate the effect of hammer peening on fatigue life of U-rib structure. The fatigue test results showed that the fatigue life of ...peened specimens are longer than the non-peened ones. In addition, the numerical results showed that compressive residual stresses were induced at weld toe and root by hammer peening, moreover that the accumulated plastic strains during cyclic loading can explain the experimental results in terms of fatigue life extension.
Although gastrointestinal involvement in patients with granulomatosis with polyangiitis is uncommon, it is associated with mild to severe life-threatening complications. We present a case of ...pneumatosis cystoides intestinalis in a patient with granulomatosis with polyangiitis that was treated successfully with hyperbaric oxygen.
A 70-year-old Japanese man with a 3-year history of granulomatosis with polyangiitis consulted our hospital with a complaint of severe back pain. Computed tomography showed a large amount of gas located in his bowel wall and mesentery. He underwent urgent exploratory laparotomy, which led to a diagnosis of pneumatosis cystoides intestinalis without intestinal perforation or necrosis. He consequently underwent 13 sessions of hyperbaric oxygen therapy and was discharged from our hospital without complications.
Several previous reports have supported the efficacy of hyperbaric oxygen for treating pneumatosis cystoides intestinalis. The present case, however, is the first in which pneumatosis cystoides intestinalis in a patient with granulomatosis with polyangiitis was successfully treated with hyperbaric oxygen. We therefore suggest that hyperbaric oxygen therapy could be a candidate treatment for pneumatosis cystoides intestinalis in patients with granulomatosis with polyangiitis.
Carbon fiber reinforced plastic, CFRP, plates bonding method is one of the new repair methods for fatigue cracks. In this method, propagation of fatigue crack will be delay because of the suppression ...of crack opening by crack bridging and stress reduction by composite effect of bonding CFRP plates. In this study, to clarify the effect of bonding CFRP plates on fatigue life extension, bending fatigue tests were carried out. First, fatigue tests on the specimens in as-welded condition were conducted until fatigue crack propagated to 10mm away from the weld toe. Then, fatigue crack was covered by CFRP plates and the specimens were re-tested until fatigue crack penetrated through the base plate. As the results of bending fatigue tests, the fatigue test data of the specimens repaired by bonding CFRP plates showed much longer fatigue life compared with that in as-welded condition, under stress ratio,
R
=0 and -infinity
PDF
