• Korean Journal of Exercise Nutrition
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• v.13 no.1
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• pp.15-21
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• 2009

Ergogenic aids are substances, devices, and practices that enhance an individual's energy use and production, and recovery from fatigue. L-carnitine increases enhance performance and aerobic capacity by stimulating lipid oxidation in muscle cells during long term exercise. L-carnitine is a well known and widely used ergogenic aid. In the present study, the effect of L-carnitine at concentrations of 100 nM, 1 μM, 10 μM, and 100 μM on the amplitude of field potential in rat cardiac muscle slices was measured using multi-channel extracellular recording (MED 64) system. In the present result, L-carnitine was shown to enhance field potential as a does-dependent manner. The increasing effect of the L-carnitine on field potential was not affected by application of the glibenclamide, an ATP-dependant K⁺ channel antagonist. The increasing effect of L-carnitine on field potential was suppressed by application of the diazoxide, an ATP-dependent K⁺ channel agonist. Present data show that L-carnitine potentiates field potentials by inhibition on ATP-dependant K⁺ channel in cardiac muscles. The enhancing effect of the L-carnitine on the field potential in cardiac muscles can be suggested as one of the underlying mechanism of ergogenic aid of the L-carnitine.

• KSBB Journal
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• v.14 no.5
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• pp.578-584
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• 1999

The lectin was purified through 0.15 M NaCl extraction, ammonium sulfate precipitation, sepharose 4B affinity chromatography and gel filtration using sephadex G-150 from the leaves of Visum album collected in Mt. Duk Yu. The final gel filtration step resulted in 11.64 folds purification with 0.14% of recovery yield. We also performed biochemical characterization of the purified Visum album lectin. HPLC analysis of lectin purified by gel filtration revealed a singel peak. The analysis of the purified lectin by SDS-PAGE showed a tetramer composed of two identical subunits with molecular weights of 32 and 30 kDa. The lectin was a glycoprotein containing 14.4% carbohydrate, which consist of glucose, fructose, arabinose and xylose, and the amino acids such as phenylalanine, lysine and tyrosine. The purified lectin agglutinated human red blood cell types with similar potency, but when tested against red blood cells from mouse, bovine, rabbit, chicken and porcine, significant difference in potency were observed. Hemaggluting activity was inhibited by D-galactose, D-mannose, D-lactose and D-raffinose, but not by D-glucose, D-glucosamine, D-mannosamine, L-fructose, D-xylose, D-arabinose, D-galacturonic acid, D-fructose, L-rhamnose and N-acetyl-D-galactosamine. The optimal pH and thermal stability of the purified lectin were pH 4.0-7.0 and 20-5$0^{\circ}C$, respectively.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 2002.05a
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• pp.127-131
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• 2002

Migration of di-(ethylhexyl)phthalate (DEHF) from PVC food packaging materials detected plasticizer into food simulanting solvents(4% Acetic acid, 8% Ethanol, 50% Ethanol, 95% Ethanol, Heptane) were studied. For executing this study ,2 PVC food packaging materials detected DEHP were used. Analysis was by GC-FID and GC-MSD(selected ion monitoring) for DEHP, and optimized for quantification of plasticizer. The recovery of DEHP into food simulanting solvents were min. 87.4${\pm}$ 3.6 ∼ max. 109.9 ${\pm}$ 10.7% respectively. Following exposure to food simulants 95% Ethanol for 24hours at 60$^{\circ}C$ the migration results of 1020.90 ${\pm}$ 10.15$\mu\textrm{g}$/g, 563.54 ${\pm}$ 5.60$\mu\textrm{g}$/dm$^2$and 73.51 ${\pm}$ 5.09$\mu\textrm{g}$/g 149.22 ${\pm}$ 10.34$\mu\textrm{g}$/dm$^2$were detected from the container for lunch and for stock fish respectively.

• Journal of Chest Surgery
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• v.30 no.3
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• pp.253-253
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• 1997

Hypothermia during lung preservation decreases metabolic processes. After the rabbit lung was flushed with modified Euro-Collins solution, heart-lung block was harvested and the left lung was assessed after ligation of the right pulmonary artery and right main-stem bronchus. Heart-lung block was immersed in the same solution for 6 hours. The modified Euro-Collins solution and storage temperature of group 1(10 cases) was 4t, roup 2(10 cases) was l0℃. On completion of the storage period, the left lung was ventilated and reperfused with blood u:high used a cross-circulating paracorporeal rabbit as a "biologic deoxygenator" for 60 minutes. Pulmonary artery pressure, airway pressure, difference in oxygen tension between mow and outflow perfusate and degree of pulmonary edema were assessed at 10-minute intervals while the left lung was ventilated at 0.8 of the inspired oxygen fraction. The mean pulmonary venous oxygen tensions at 10 and 60 minutes after reperfusion were 209.52±42.46 and 103.48± 15.96 mmHg in group I versus 247.78±36.19 and 147.91 ± 11.07 mmHg in group II(p=0.049, (0.0001). The mean alveolar-arterial oxygen differences at 20 and 60 minutes after reperfusion were 357. 95± 12.84 and 437.31 14.26 mmHg in group I versus 310.88±3).47 and )90.93± 15.86 mmHg in group II (p=0.0092, (0.0001). The mean pulmonary arterial pressures at 10 and 60 minutes after reperfusion were 40.56± 18.66 and 87. 2± 17.22 mmHg in group I versus 31.22±6.84 and 65.78± 11.02 mmHg in group rl (p : 0.048, 0.0062). The mean pulmonary vascular resistances at 10 and 60 minutes after reperfusion were 2.69±0.85 and 4.36±0.86 mmHg/ml/min in group I versus 1.99±0.39 and 3.29±0.55 mmHg/ml/min in group II(p : 0.0323, 0.0062). There were no difference between groups in peak airway pressure, lung compliance and degree of pulmonary edema. In conclusion that preservation of lung at l0℃ was superior to preservation at 4℃.

• Pediatric Infection and Vaccine
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• v.22 no.1
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• pp.23-28
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• 2015

Purpose: The aim of this study was to investigate the clinical manifestations and laboratory characteristics of eosinophilic meningitis in Severance Children's Hospital. Methods: We examined 6,335 children under the age of 18 years old who had visited the tertiary hospital in Seoul, Korea, and had received cerebrospinal study results between January 2007 and July 2012. The medical records of the patients identified as eosinophilic meningitis were retrospectively reviewed. Results: Eosinophilic meningitis was diagnosed in 39 patients (0.6%). The mean age was 6 years (range 0-18 years) and the sex ratio was 1.3:1 (22 males and 17 females). The underlying diseases and past history were neurologic disease (n=36, 92%). Eosinophilic meningitis was diagnosed in thirty-five patients who had undergone postoperation neurosurgery (90%). The most common symptoms were fever (50%), headache (20%), vomiting (15%), seizure (10%), and dizziness (5%). The average duration for recovery was five days, and intravenous antibiotics or steroids were used. Conclusions: Manifestations of eosinophilic meningitis are similar to other types of meningitis. The most common cause of eosinophilic meningitis in children was neurosurgery. Eosinophilic meningitis should be considered for patients showing fever and headache after neurosurgery. Through careful investigation, use of improper antibiotics could be avoided.

• Journal of Food Hygiene and Safety
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• v.35 no.2
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• pp.109-117
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• 2020

This study aimed to develop an analytical method for determination of 18 dyes in livestock and fishery products by liquid chromatograph-tandem mass spectrometry (LC-MS/MS). The developed method was validated for linearity, accuracy, limit of quantifications (LOQ) and recovery based on the CODEX guideline (CAC/GL-71). Target matrices (beef, pork, chicken, egg, milk, flatfish, eel, and shrimp) were extracted using acetonitrile (containing 1% of acetic acid) and then, purified with C₁₈ and primary secondary amine (PSA). Calibration linearity was obtained (r²>0.98) and LOQs were 0.002 mg/kg in animal products. The recoveries of dyes were ranged from 63 to 112% and relative standard deviations (RSDs, %) were less than 15%. The residues of 18 dyes were investigated in real samples (n=124) collected from retail markets in South Korea. As a result, a total of seven samples showed positive results for target analytes in fish samples. However, there was no violation according to the maximum residue limits set by the Korean Food Code. The proposed method will be used for routine analysis of dye residues in livestock and fishery products.

• Journal of Pharmaceutical Investigation
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• v.36 no.1
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• pp.23-29
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• 2006

A rapid, selective and sensitive reversed-phase HPLC method for the determination of promethazine in human serum was developed, validated, and applied to the pharmacokinetic study of promethazine. Promethazine and internal standard, chlorpromazine, were extracted from human serum by liquid-liquid extraction with n-hexane containing 0.8% isopropanol and analyzed on a Capcell Pak CN column with the mobile phase of acetonitrile-0.2 M potassium dihydrogen phosphate (42:58, v/v, adjusted to pH 6.0 with 1 M NaOH). Detection wavelength of 251 nm and flow rate of 0.9 mL/min were fixed for the study. The assay robustness for the changes of mobile phase pH, organic solvent content, and flow rate was confirmed by $3^{3}$ factorial design using a fixed promethazine concentration (10 ng/mL) with respect to its peak area and retention time. In addition, the ruggedness of this method was investigated at three different laboratories using same quality control (QC) samples. This method showed linear response over the concentration range of 1-40 ng/mL with correlation coefficients greater than 0.999. The lower limit of quantification using 1 mL of serum was 1 ng/mL, which was sensitive enough for pharmacokinetic studies. The overall accuracy of the quality control samples ranged from 96.15 to 105.40% for promethazine with overall precision (% C.V.) being 6.70-11.22%. The relative mean recovery of promethazine for human serum was 63.54%. Stability (freeze-thaw and short-term) studies showed that promethazine was stable during storage, or during the assay procedure in human serum. However, the storage at $-80^{\circ}C$ for 4 weeks showed that promethazine was not stable. Extracted serum sample and stock solution were not allowed to stand at ambient temperature for 12 hr prior to injection. The peak area and retention time of promethazine were not significantly affected by the changes of mobile phase pH, organic solvent content, and flow rate under the conditions studied. This method showed good ruggedness (within 15% C.V.) and was successfully used for the analysis of promethazine in human serum samples for the pharmacokinetic studies of orally administered Himazin tablet (25 mg as promethazine hydrochloride) at three different laboratories, demonstrating the suitability of the method.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.1
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• pp.8-16
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• 1998

Sexual maturation and reproductive cycle of the goldeye rockfish, Sebastes thompsoni were investigated under photomicroscopy. Samples were collected monthly in the coastal water of Samcheonpo ($34^{\circ}55'N$ ), Korea from November 1995 to October 1996, The ovary consists of several ovarian lamellae originated from ovarian outer membrane. Oogonia which are originated from the inner surface of the ovarian lamella protrude to the ovarian cavity in oocyte stage, and they ave suspended by the egg stalk. The testis is seminiferous tubule type in internal structure. Seminiferous tubule consists of many testicular cysts which contain numerous germ cells in same developmental stage. Biological minimum size of female and male were 19.5 cm and 21.5 cm in total length, respectively. Gonadosomatic index (GSI) of female was the highest (9.56) in March and the lowest (0.15) in August. GSI of male was the highest (0.25) in February and the lowest (0.04) in July. Reproductive cycle was classified into the following successive stages: in female, growing (October and November), maturation ( $December\~February$), gestation (March), parturition and recovery ($April\~June$) and resting ($July\~September$), and in male, growing ($September\~November$), maturation ( December and January), ripe and copulation ( February and March) and degeneration and resting ($April\~August$).

• Journal of Food Hygiene and Safety
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• v.36 no.5
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• pp.376-381
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• 2021

Red beet (Beta vulgaris L.) is a root vegetable and a popular functional food ingredient of dark red-purple appearance due largely to betacyanins, principally betanine (75-95%) and its isomer, isobetanine (15-45%). This study developed an analytical method for beet red in terms of betanine and isobetanine in processed food products labeled with beet red as a food additive. High Performance Liquid Chromatography-Diode Array Detector (HPLC-DAD) was used with a C₁₈ column. Linearity, limit of detection (LOD), limit of quantitation (LOQ), accuracy, precision and uncertainty in measurement were calculated for method validation. Matrix-matched calibration was applied to the candy, ice cream, and cocoa product, respectively, and R² was ≥0.9998, showing a high level of linearity. The LOD and LOQ were 0.16 to 0.32 and 0.48 to 0.97 mg/L, respectively. As a result of repeated intra-day and interday experiments to validate the accuracy and precision of the analytical method, the recovery rates were 96.0-103.1% and 100.0-102.2%, respectively and the RSD% was 0.5-3.3% and 0.9-3.8%, respectively. Moreover, the measurement uncertainty was estimated to be 1.71-12.43% depending on the matrix and the measured concentration. In this study, betanine and isobetanine were quantified (8.4-3,823.4 mg/kg) by applying the developed analytical method to processed food products (n= 26; e.g., candy, ice cream, and other processed foods) labeled with beet red as a food additive.

• Korean Journal of Soil Science and Fertilizer
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• v.15 no.2
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• pp.117-127
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• 1982

Mulberry plants (Morus alba L.) were grown in pots with the following different nitrogen sources: ammonium sulphate, urea, ammonium nitrate, sodium nitrate + ammonium nitrate ($NO_3:NH_4$=2:1), and sodium nitrate. The effects of the nitrogen sources on mulberry yields, nitrogen recovery, distribution of ions and cation-anion balance (C-A) along leaf sequence and growth stage were investigated. The results were as follows: 1. Leaf yields and nitrogen recovery decreased with increasing $NO_3$-N application rates. 2. Relative cation contents in leaves in the early growth stages showed the following pattern : Na < Mg < Ca < K. However, the order of Ca and K reversed in the later stages. The order of anion contents chifted from $SO_4$ < $NO_3$ < Cl < $H_2PO_4$ in the early stages to $NO_3$ < Cl < $SO_4$ < $H_2PO_4$ in the later stages. 3. Contents of K, $H_2PO_4$, $SO_4$, $NO_3$, T-N and the sum of anion contents (${\sum}A$) were higher in upper leaves whereas Ca, Mg, Cl, the sum of cation contents (${\sum}C$) and (C-A) were higher in lower leaves. 4. When $NO_3$ in leaves decreased, Cl and K as counter-cations increased and consequently Ca decreased. 5. The (C-A) in leaves varied with leaf sequence and growth stage from 700 to 900 me/kg D.M.