• Korean Journal of Clinical Pharmacy
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• v.29 no.2
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• pp.101-108
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• 2019

Background: High doses of methotrexate (MTX) are often used in various chemotherapy protocols to treat acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL) in children, but its delayed elimination increases the occurrence of adverse events, such as bone marrow suppression. The aim of this study was to investigate the elimination of MTX at 24 and 48 hours. Methods: We retrospectively analyzed electronic medical records of ALL or NHL pediatric patients who received $5g/m^2$ MTX infusion over 24 hours (between June, 2012 and July, 2018) at the Yonsei University Health System, Korea. The delayed elimination of MTX concentrations was assessed with 100 or $150{\mu}M$ MTX at 24 hours, and 2 or $5{\mu}M$ at 48 hours. Results: Among the 85 MTX cycles administered, 23 cycles were classified in delayed elimination group, and 62 cycles showed normal elimination. At 24 hours, the delayed elimination group with MTX concentration > $100{\mu}M$ showed higher percentage than group with MTX concentration < $100{\mu}M$ (45.8% vs. 19.7%, p = 0.015). However, no differences were observed at $150{\mu}M$ MTX (p = 0.66). At 48 hours, the delayed elimination was higher than the normal elimination at both concentration baselines (p < 0.001 at $2{\mu}M$, p = 0.024 at $5{\mu}M$). Conclusions: MTX concentrations greater than $100{\mu}M$ show high probability of delayed elimination at 24 hours. When MTX levels are above normal, leucovorin and hydration regimens should be continued to prevent delayed elimination.

• Journal of Power Electronics
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• v.16 no.2
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• pp.717-730
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• 2016

The harmonic components of grid voltage result in oscillations of the calculated phase obtained via phase synchronization. This affects the security and stability of grid-connected converters. Moving average filter, delayed signal cancellation and their related harmonic elimination algorithms are major methods for such issues. However, all of the existing methods have their limitations in dealing with multiple harmonics issues. Furthermore, few studies have focused on a comparison and evaluation of these algorithms to achieve optimal algorithm selections in specific applications. In this paper, these algorithms are quantitatively analyzed based on the derived mathematical models. Moreover, an enhanced moving average filter and enhanced delayed signal cancellation algorithms, which are applicable for eliminating a group of selective harmonics with only one calculation block, are proposed. On this basis, both a comprehensive comparison and a quantitative evaluation of all of the aforementioned algorithms are made from several aspects, including response speed, required data storage size, sensitivity to sampling frequency, and elimination of random noise and harmonics. With the conclusions derived in this paper, better overall performance in terms of harmonic elimination can be achieved. In addition, experimental results under different conditions demonstrate the validity of this study.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.825-828
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• 1999

In this paper, we design the analog phase shifter for the elimination of the ghost signal. Compensation of the delay between the reference signal and the relatively delayed signal is possible. This phase shifter uses the vector summing method. We use for the attenuator in our system FETs. The phase shifter is operated at the 200MHz and composed by lumped elements. The proposed analog phase shifter is simulated by the HP ADS software.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.7
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• pp.1331-1338
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• 2007

A new method for detecting and eliminating the Electrocardiogram(ECG) artifact from the scalp Electroencephalogram(EEG) is proposed. Based on the single channel EEG, the proposed method consists of 4 procedures: emphasizing the R-wave of ECG artifact from EEG using the least squares acceleration(LSA) filter, detecting the R-wave from the LSA filtered EEG using the phase space method and R-R interval, generating the delayed impulse synchronized to the R-wave and elimination of the ECG artifacts based on the adaptive digital filter using the impulse and raw EEG. The performance of the proposed method was evaluated in the two separating parts of R-wave detection and, ECG estimation and elimination from EEG. In the R-wave detection, the proposed method showed the mean error rate of 6.285(%). In the ECG estimation and elimination using simulated and/or real EEG recordings, we found that the ECG artifacts were successfully estimated and eliminated in comparison with the conventional multi-channel techniques, in which independent component analysis and ensemble average method are used. From this we can conclude that the proposed method is useful for the detecting and eliminating the ECG artifact from single channel EEG and simple for ambulatory/portable EEG monitoring system.

• Journal of The Korean Society of Clinical Toxicology
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• v.12 no.2
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• pp.39-45
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• 2014

Purpose: The purpose of this study is to review the evidence comparing the efficacy and safety between L-carnitine and extracorporeal elimination therapy in the management of acute valproic acid L-carnitine vs Extracorporeal Elimination for Acute Valproic acid Intoxication Methods: PubMed, Embase, Cochrane library, Web of Science, KoreaMed, KMbase, and KISS were searched, using the terms carnitine and valproic acid. All studies, regardless of design, reporting efficacy or safety endpoints were included. Reference citations from identified publications were reviewed. Both English and Korean languages were included. Two authors extracted primary data elements including poisoning severity, presenting features, clinical management, and outcomes. Results: Thirty two articles including 33 cases were identified. Poisoning severity was classified as 3 mild, 11 moderate, and 19 severe cases. Nine cases were treated with L-carnitine while 24 cases received extracorporeal therapy without L-carnitine. All patients except one expired patient treated with hemodialysis recovered clinically and no adverse effects were noted. A case report comparing two patients who ingested the same amount of valproic acid showed increased ICU stay (3 vs 11 days) in case of delayed extracorporeal therapy. Conclusion: Published evidence comparing L-carnitine with extracorporeal therapy is limited. Based on the available evidence, it is reasonable to consider L-carnitine for patients with acute valproic acid overdose. In case of severe poisoning, extracorporeal therapy would also be considered in the early phase of treatment.

• Toxicological Research
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• v.14 no.4
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• pp.557-562
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• 1998

Allyl alcohol is metabolized in the liver through two steps, first to reactive acrolein by alcohol dehydrogenase (ADH), subsequently to acrylic acid by aldehyde dehydrogenase (ALDH). Since ethanol could compete the same enzymes to be metabolized in the liver, we have determined the plasma concentrations of allyl alcohol and ethanol followed by combined treatment. Pretreatment of rats with 2g/kg ethanol followed by ip administration of 40mg/kg allyl alcohol increased the lethality significantly. Determination of in vivo blood concentrations revealed that ethanol pretreatment caused the apparent decrease in allyl alcohol clearance, whereas acetaldehyde level in blood increased significantly by allyl alcohol treatment, as determined by head space GC analysis. Treatment of 4-methylpyrazole, an inhibitor of ADH, delayed allyl alcohol elimination significantly and reduced its lethality. Collectively, these findings suggested that reduction of allyl alcohol clearance in the presence oj ethanol was mediated through ADH competitive inhibition.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.5
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• pp.677-684
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• 1998

The distribution and elimination of oxolinic acid (OA) following oral (80mg/kg body weight) and bath (20 mg/$\ell$) treatment were examined in the organs and plasma of Nile tilapia (Oreochromis niloticus) on different temperatures and physiological conditions using a bioassay method. On the analysis of temperature effect, both absorption and elimination of OA after oral administration were delayed in the group at $15^{\circ}C$. but significant difference of the peak concentrations in the tissues of the groups at $15^{\circ}C$ and $25^{\circ}C$ was not revealed. However, the changes of maximam concentration, absorption and elimination rates in the tissues of fish following bath treatment depending on different temperatures were more significantly different from the results of the studies with oral administration. The pharmacokinetics of OA in the tissues of diseased fish, the main target of drug treatment, also appeared to be distinguishable from those of healthy fish.

• Journal of Pharmaceutical Investigation
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• v.22 no.1
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• pp.11-21
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• 1992

The effects of colchicine on the plasma elimination and biliary excretion of various organic anions in rats were examined. Elimination of indocyanine green (ICG) or rose bengal (RB) from plasma was significantly delayed when rats were treated with colchicine (3 mg/kg body weight) 3 hr prior to the administration of the dye. On the other hand, disappearance of sulfobromophthalein (BSP) or bromophenol blue (BPB) from plasma was not influenced by colchicine. The plasma disappearance and biliary excretion of organic anions were kinetically analyzed based on a compartment model, in which the deep compartment and the unknown disposition are incorporated. The transfer rate constants of ICG or RB, $k_{23}$ (from the liver to the deep compartment) and $k_{3B}$ (from the deep compartment to the bile), were decreased by colchicine, but those of BSP or BPB were not changed. A mechanism for the decrease in the $k_{23}$ and $k_{3B}$ values for ICG and RB might be explained by a inhibition of colchicine to the intracellular cytoskeleton. The hepatocellular distribution of RB or BPB was then determined. BPB mainly distributed to the cytosolic fraction, but RB distributed to each hepatocyte organelle. Taken together. it was suggested that ICG or RB is transported through hepatocytes into bile with the aid of the cytoskeleton, whereas BSP or BPB is handled by hepatocytes in a different way.

• Clinical and Experimental Pediatrics
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• v.54 no.1
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• pp.6-10
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• 2011

Many patients assume that allergic reactions against foods are responsible for triggering or worsening their allergic symptoms. Therefore, it is important to identify patients who would benefit from an elimination diet, while avoiding unnecessary dietary restrictions. The diagnosis of food allergy depends on the thorough review of the patients's medical history, results of supplemented trials of dietary elimination, and in vivo and in vitro tests for measuring specific IgE levels. However, in some cases the reliability of such procedures is suboptimal. Oral food challenges are procedures employed for making an accurate diagnosis of immediate and occasionally delayed adverse reactions to foods. The timing and type of the challenge, preparation of patients, foods to be tested, and dosing schedule should be determined on the basis of the patient's history, age, and experience. Although double-blind, placebo-controlled food challenges(DBPCFC) are used to establish definitively if a food is the cause of adverse reactions, they are time-consuming, expensive and troublesome for physician and patients. In practice, An open challenge controlled by trained personnel is sufficient especially in infants and young children. The interpretation of the results and follow-up after a challenge are also important. Since theses challenges are relatively safe and informative, controlled oral food challenges could become the measure of choice in children.

• Molecules and Cells
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• v.28 no.6
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• pp.559-563
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• 2009

Glyceraldehyde-3-phosphate is a key intermediate in several central metabolic pathways of all organisms. Aldolase and glyceraldehyde-3-phosphate dehydrogenase are involved in the production or elimination of glyceraldehyde-3-phosphate during glycolysis or gluconeogenesis, and are differentially expressed under various physiological conditions, including cancer, hypoxia, and apoptosis. In this study, we examine the effects of glyceraldehyde-3-phosphate on cell survival and apoptosis. Overexpression of aldolase protected cells against apoptosis, and addition of glyceraldehyde-3-phosphate to cells delayed apoptosis. Additionally, delayed apoptotic phenomena were observed when glyceraldehyde-3-phosphate was added to a cell-free system, in which artificial apoptotic process was induced by adding dATP and cytochrome c. Surprisingly, glyceraldehyde-3-phosphate directly suppressed caspase-3 activity in a reversible noncompetitive mode, preventing caspase-dependent proteolysis. Based on these results, we suggest that glyceraldehyde-3-phosphate, a key molecule in several central metabolic pathways, functions as a molecule switch between cell survival and apoptosis.