1,315 research outputs found

    Sargassum fulvellum

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    Ultraviolet (UV) radiation has been reported to induce cutaneous inflammation such as erythema and edema via induction of proinflammatory enzymes and mediators. Sargassum fulvellum is a brown alga of Sargassaceae family which has been demonstrated to exhibit antipyretic, analgesic, antiedema, antioxidant, antitumor, fibrinolytic, and hepatoprotective activities. The purpose of this study is to investigate anti-inflammatory effects of ethylacetate fraction of ethanol extract of Sargassum fulvellum (SFE-EtOAc) in HaCaT keratinocytes and BALB/c mice. In HaCaT cells, SFE-EtOAc effectively inhibited UVB-induced cytotoxicity (60 mJ/cm2) and the expression of proinflammatory proteins such as cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), and inducible nitric oxide synthase (iNOS). Furthermore, SFE-EtOAc significantly reduced UVB-induced production of proinflammatory mediators including prostaglandin E2 (PGE2) and nitric oxide (NO). In BALB/c mice, topical application of SFE-EtOAc prior to UVB irradiation (200 mJ/cm2) effectively suppressed the UVB-induced protein expression of COX-2, iNOS, and TNF-α and subsequently attenuated generation of PGE2 and NO as well. In another experiment, SFE-EtOAc pretreatment suppressed UVB-induced reactive oxygen species production and exhibited an antioxidant potential by upregulation of antioxidant enzymes such as catalase and Cu/Zn-superoxide dismutase in HaCaT cells. These results suggest that SFE-EtOAc could be an effective anti-inflammatory agent protecting against UVB irradiation-induced skin damages

    Evaluation of the added mass for a spheroid-type unmanned underwater vehicle by vertical planar motion mechanism test

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    ABSTRACTThis paper shows added mass and inertia can be acquired from the pure heaving motion and pure pitching motion respectively. A Vertical Planar Motion Mechanism (VPMM) test for the spheroid-type Unmanned Underwater Vehicle (UUV) was compared with a theoretical calculation and Computational Fluid Dynamics (CFD) analysis in this paper. The VPMM test has been carried out at a towing tank with specially manufactured equipment. The linear equations of motion on the vertical plane were considered for theoretical calculation, and CFD results were obtained by commercial CFD package. The VPMM test results show good agreement with theoretical calculations and the CFD results, so that the applicability of the VPMM equipment for an underwater vehicle can be verified with a sufficient accuracy

    Structure stability evaluation of offshore heave compensator using multi-body dynamics analysis method

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    Heave compensator attenuate vessel heave motion during drilling operation of drillship. Heave compensator functions as damping form motion of drillship, such as principle spring of suspension system. The load transfers on the parts of heave compensator. Stress and deformation of all parts is evaluated to diagnose the stability of the compensator. This study makes a decision on the safety of structure. Results of analysis confirm the structure stability of heave compensator for simulation. This result can be used as data for structural analysis to determine safety of a structure

    Out-of-Plane Strengthening of Unreinforced Masonry Walls by Glass Fiber-Reinforced Polyurea

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    Fiber-reinforced polymer reinforcement or polyurea reinforcement techniques are applied to strengthen unreinforced masonry walls (UMWs). The purpose of this experimental study is to verify the out-of-plane reinforcing effect of sprayed glass fiber-reinforced polyurea (GFRPU), which is a composite elastomer made of polyurea and milled glass fibers on UMW. The out-of-plane strengths and ductile behaviors based on various coating shapes are compared in this study. An empirical formula to describe the degree of reinforcement on the out-of-plane strength of the UMW is derived based on the experimental results. It is observed that the peak load-carrying capacity, ductility, and energy absorption capacity gradually improve with an increase in the strengthening degree or area. Compared with the existing masonry wall reinforcement method, the GFRPU technique is a construction method that can help improve the safety performance along with ease of construction and economic efficiency. Doi: 10.28991/CEJ-2022-08-01-011 Full Text: PD

    In-Plane Strengthening of Unreinforced Masonry Walls by Glass Fiber-Reinforced Polyurea

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    Strengthening techniques have been employed in Korea to unreinforced masonry walls (UMWs) for several years to protect them from damage caused by the intermittent occurrence of earthquakes. Polyurea, which has a high tensile strength and elongation rate, can be utilized as a strengthening material to enhance the in-plane strength and ductility of UMWs. Glass fiber-reinforced polyurea (GFRPU) is a composite elastomer manufactured by progressively adding milled glass fiber to polyurea. The purpose of this study is to investigate the enhancement of the in-plane strength and ductility of UMWs using GFRPU, depending on the shape of the GFRPU coating on the wall. Four masonry wall specimens are tested with test variables of the number of strengthening sides and coating shapes. It is illustrated that the GFRPU reinforcement of masonry wall leads to enhanced load-carrying capacity, ductility, and energy absorption. An empirical formula to represent the degree of strengthening effected by GFRPU is proposed in this study. Doi: 10.28991/cej-2021-03091782 Full Text: PD

    The relationship between the effect-site concentration of propofol and sedation scale in children: a pharmacodynamic modeling study

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    Background Continuous infusion of propofol has been used to achieve sedation in children. However, the relationship between the effect-site concentration (Ce) of propofol and sedation scale has not been previously examined. The objective of this study was to investigate the relationship between the Ce of propofol and the University of Michigan Sedation Scale (UMSS) score in children with population pharmacodynamic modeling. Methods A total of 30 patients (aged 3 to 6 years) who underwent surgery under general anesthesia with propofol and remifentanil lasting more than 1 h were enrolled in this study. Sedation levels were evaluated using the UMSS score every 20 s by a 1 μg/mL stepwise increase in the Ce of propofol during the induction of anesthesia. The pharmacodynamic relationship between the Ce of propofol and UMSS score was analyzed by logistic regression with nonlinear mixed-effect modeling. Results The estimated Ce50 (95% confidence interval) of propofol to yield UMSS scores equal to or greater than n were 1.84 (1.54–2.14), 2.64 (2.20–3.08), 3.98 (3.66–4.30), and 4.78 (4.53–5.03) μg/mL for n = 1, 2, 3, and 4, respectively. The slope steepness for the relationship of the Ce versus sedative response to propofol (95% confidence interval) was 5.76 (4.00–7.52). Conclusions We quantified the pharmacodynamic relationship between the Ce of propofol and UMSS score, and this finding may be helpful to predict the sedation score at the target Ce of propofol in children. Trial registration http://www.clinicaltrials.gov (No.: NCT03195686 , Date of registration: 22/06/2017)

    Black rice (Oryza sativa L.) extract attenuates hepatic steatosis in C57BL/6 J mice fed a high-fat diet via fatty acid oxidation

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    <p>Abstract</p> <p>Background</p> <p>Two major risk factors for the onset of fatty liver disease are excessive alcohol intake and obesity, the latter being associated with non-alcoholic fatty liver disease (NAFLD). The aim of this study was to examine the effects of black rice extract (BRE) on hepatic steatosis and insulin resistance in high-fat diet-fed mice, providing a model of NAFLD.</p> <p>Methods</p> <p>Twenty-four mice were randomly divided into three groups (n = 8 in each group): normal fat diet (ND), high fat diet (HF), and high fat diet supplemented with 1% (w/w) BRE (HF +1% BRE). The experimental diets were fed for seven weeks.</p> <p>Results</p> <p>A HF induced hepatic steatosis with significant increases in the serum levels of free fatty acids (FFAs), triglyceride (TG), total cholesterol (TC), and insulin. By contrast, supplementary BRE (10 g/kg of diet) included in the HF alleviated hepatic steatosis and significantly decreased serum TG and TC levels (p < 0.01 for both). Dietary BRE also increased expression of fatty acid metabolism-related genes, including carnitine palmitoyltransferase (CPT1A), acyl-CoA oxidase (ACO), cytochrome P450 (CYP4A10), and peroxisome proliferator activated receptor (PPAR)-α (p < 0.05 for all).</p> <p>Conclusions</p> <p>Dietary BRE supplementation improved serum lipid profiles and significantly enhanced mRNA expression levels of fatty acid metabolism-related genes, primarily via β-oxidation and ω-oxidation in the liver. Taken together, these findings suggest that a BRE-supplemented diet could be useful in reducing the risks of hepatic steatosis and related disorders, including hyperlipidemia and hyperglycemia.</p

    Conventional reversal of rocuronium-induced neuromuscular blockade by sugammadex in Korean children: pharmacokinetics, efficacy, and safety analyses

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    Background: Sugammadex is known to reverse neuromuscular blockade induced by non-depolarizing agents. In children, the recommended dose for reversal of moderate neuromuscular blockade is 2 mg/kg. We investigated the pharmacokinetics and pharmacodynamics of sugammadex in Korean children.Methods: Children (2–17 years of age) undergoing brain or spine surgery were enrolled and randomly assigned to control (neostigmine) and 2, 4, or 8 mg/kg sugammadex groups. Following induction of anesthesia and monitoring of the response to train-of-four stimulation, 1 mg/kg rocuronium was intravenously administered. Upon reappearance of the second twitch to train-of-four stimulation, the study drug was administered according to group allocation. The plasma concentrations of rocuronium and sugammadex were serially measured at nine predefined time points following study drug administration. To determine efficacy, we measured the time elapsed from drug administration to recovery of T4/T1 ≥ 0.9. For pharmacokinetics, non-compartmental analysis was performed and we monitored adverse event occurrence from the time of study drug administration until 24 h post-surgery.Results: Among the 29 enrolled participants, the sugammadex (2 mg/kg) and control groups showed recovery times [median (interquartile range)] of 1.3 (1.0–1.9) and 7.7 (5.3–21.0) min, respectively (p = 0.002). There were no significant differences in recovery time among the participants in sugammadex groups. The pharmacokinetics of sugammadex were comparable to those of literature findings. Although two hypotensive events related to sugammadex were observed, no intervention was necessary.Conclusion: The findings of this pharmacokinetic analysis and efficacy study of sugammadex in Korean children indicated that sugammadex (2 mg/kg) may be safely administered for reversing moderate neuromuscular blockade. Some differences in pharmacokinetics of sugammadex were observed according to age.Clinical Trial Registration:http://clinicaltrials.gov (NCT04347486

    Learning curve of fiberoptic bronchoscope-guided tracheal intubation through supraglottic airway device for pediatric airway management: a manikin study

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    Background Although fiberoptic-guided endotracheal intubation using a supraglottic airway device (SAD) is a good alternative for the management of difficult airways, its learning curve for residents has not been evaluated in pediatric patients. We aimed to train residents using a pediatric manikin and obtain learning curves to evaluate the efficiency of the training. Methods We conducted a single-armed prospective study with anesthesiology residents. Plain endotracheal tube (ETT) intubation guided by a fiberoptic bronchoscope through Ambu® AuraGainTM was demonstrated in a pediatric manikin to the participants before training. The procedure was divided into four steps: SAD insertion, vocal cord identification, carina identification, and ETT insertion into the trachea. The results and elapsed procedure times of each trial were recorded. The learning curves for the participants were constructed and analyzed using the cumulative sum method. Results All the 30 participants acquired proficiency at the end of practice between eight and 25 trials. The overall success rate for the procedure was 92.8%, and above 80% for all participants. Mean ± standard deviation procedure time was 71.3 ± 50.7 s. The 4th step accounted for 86.2% and 48.0% of the total failures and procedure time, respectively. The procedure time rapidly decreased in the 2nd trial; a modest decline was observed thereafter. Conclusions Trainees can obtain proficiency for fiberoptic-guided intubation through SAD within 25 times when using pediatric manikin. Effect of the training on performance in actual clinical situation should be studied
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