• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.5-5
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• 2001

This study was to test whether Hanwoo in vitro matured oocytes can be successfully cryopreserved by a new vitrification procedure using MVC method. For the vitrification, oocytes were pretreated in 10% ethylene glycol (EG10) for 5-10 min, exposed in EG30 for 30 sec, each oocytes were individually put on the inner wall of 0.25 $m\ell$ straw, and then straws were directly plunged into L$N_2$. Thawing was taken by 4-step procedures [1.0 Msucrose (MS), 0.5 MS, 0.25 MS, and 0.125 MS] at 37$^{\circ}C$. In vitro developmental capacity (survival, cleavage ($\geq$2-cell) and blastocyst rates) in vitrified group was no significant difference compared to that in other treatment groups (exposed; 100.0, 74.4, 32.3% and control; 100.0, 78.3, 36.3%): high mean percentage of oocytes (91.2%) was survived, 69.4% of them were cleaved and 27.9% of cleaved embryos were developed to blastocyst. Especially, after transfer of in vitro developed embryos in vitrified group, four of six recipient animals were found to pregnant and three of them were ongoing pregnant by manual palpation at 250 days after transfer. However, among them, two healthy female calves (23 and 25kg) were born. This result demonstrates that MVC method is very appropriate freezing method for the Hanwoo in vitro matured oocytes and that ovum bank can be maintained efficiently by MVC cryopreservation method.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.1
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• pp.61-70
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• 2005

This study investigated the spinal loads(L5/S1 disc compression and shear forces) predicted from four biomechanical models: one EMG model and three optimization models. Three objective functions used in the optimization models were to miminize 1) the cubed muscle forces : MF3, 2) the cubed muscle stress : MS3, 3) maximum muscle intensity : MI. Twelve healthy male subjects participated in the isometric voluntary exertion tests to six directions : flexion/extension, left/right lateral bending, clockwise/ counterclockwise twist. EMG signals were measured from ten trunk muscles and spinal loads were assessed at 10, 20, 30, 40, 50, 60, 70, 80, 90%MVE(maximum voluntary exertion) in each direction. Three optimization models predicted lower L5/S1 disc compression forces than the EMG model, on average, by 31%(MF3), 27%(MS3), 8%(MI). Especially, in twist and extension, the differences were relatively large. Anterior-posterior shear forces predicted from optimization models were lower, on average, by 27%(MF3), 21%(MS3), 9%(MI) than by the EMG model, especially in flexion(MF3 : 45%, MS3 : 40%, MI : 35%). Lateral shear forces were predicted far less than anterior-posterior shear forces(total average = 124 N), and the optimization models predicted larger values than the EMG model on average. These results indicated that the optimization models could underestimate compression forces during twisting and extension, and anterior-posterior shear forces during flexion. Thus, future research should address the antagonistic coactivation, one major reason of the difference between optimization models and the EMG model, in the optimization models.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.9
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• pp.1227-1232
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• 2008

Carcass characteristics data of Hanwoo (N = 1,084) were collected from two stations of the National Livestock Institute of Animal Science (NIAS), Korea and records from thirteen individual cow-calf operators were analyzed to estimate variance and covariance components and the effect of different slaughter endpoints. Carcass traits analyzed were cold carcass weight (CWT, kg), REA (rib eye area, cm2), back fat thickness (mm) and marbling score (1-7). Four different models were examined. All models included sex and contemporary group as fixed effects and the animal's direct genetic potential and environment as random effects. The first model fitted a linear covariate of age at slaughter. The second model fitted both linear and quadratic covariates of age at slaughter. The third model fitted a linear covariate of body weight at slaughter. The fourth model fitted both linear covariates of age at slaughter and body weight at slaughter. Variance components were estimated using the REML procedure with Gibb's sampler. Heritability estimate of CWT was in the range of 0.08-0.11 depending on the model applied. Heritability estimates of BF, REA and MS were in the ranges of 0.23-0.28, 0.19-0.26, and 0.44-0.45, respectively. Genetic correlations between CWT and BF, between CWT and REA, and between CWT and MS were in the ranges of -0.33 - -0.14, 0.73-0.84, and -0.01- 0.11, respectively. Genetic correlations between REA and BF, between MS and BF and between REA and MS were in the ranges of -0.82 ~ -0.72, 0.04~0.28 and -0.08 ~ -0.02, respectively. Variance and covariance components estimated varied by model with different slaughter endpoints. Body weight endpoint was more effective for direct selection in favor of yield traits and body weight endpoints affected more of the correlated response to selection for the traits of yield and quality of edible portion of beef.

• Nutrition Research and Practice
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• v.7 no.6
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• pp.495-502
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• 2013

Recent studies suggest that vitamin D deficiency and cardiometabolic disorders are becoming increasingly more prevalent across multiple populations. However, there is a lack of comprehensive data for Korean adults. We investigated the vitamin D status, the prevalence of vitamin D deficiency and its association with metabolic syndrome (MS) risk in Korean adults aged 20 years or older. The study subjects (n = 18,305) were individuals who participated in the Korean National Health Examination and Nutrition Survey (KNHANES) in 2008-2010. Vitamin D status (25-hydroxyvitamin D [25(OH)D]) was categorized as < 20, 21-29, and ${\geq}$ 30 ng/mL, which are the cut-off points for deficiency, insufficiency and normal limits. A wide variety of cardiometabolic risk factors were compared according to the vitamin D status. Vitamin D deficiency was found in 53.9% of men and 70.5% of women. Mean BMI, systolic BP, HbA1c and low density lipoprotein cholesterol (LDL-C) were highest in the vitamin D deficiency group in both genders. Further, the MS was most prevalent in the vitamin D deficiency group in both genders (12.3%, P = 0.002 in men and 9.2%, P < 0.001 in women). Compared to the vitamin D normal group, the adjusted odds ratio (ORs) (95% confidence interval [95% CI]) for MS in the vitamin D deficiency group were 1.46 (1.05-2.02) in men and 1.60 (1.21-2.11) in women, after adjusting for confounding variables. In conclusion, Vitamin D deficiency is a very common health problem in Korean adults and is independently associated with the increasing risk of MS.

• Journal of Ginseng Research
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• v.38 no.3
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• pp.220-225
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• 2014

An efficient in vitro protocol has been established for somatic embryogenesis and plantlet conversion of Korean wild ginseng (Panax ginseng Meyer). Wild-type and mutant adventitious roots derived from the ginseng produced calluses on Murashige and Skoog (MS) medium supplemented with 0.5 mg/L 2,4-dichlorophenoxyacetic acid and 0.3 mg/L kinetin; 53.3% of the explants formed callus. Embryogenic callus proliferation and somatic embryo induction occurred on MS medium containing 0.5 mg/L 2,4-dichlorophenoxyacetic acid. The induced somatic embryos further developed to maturity on MS medium with 5 mg/L gibberellic acid, and 85% of them germinated. The germinated embryos were developed to shoots and elongated on MS medium with 5 mg/L gibberellic acid. The shoots developed into plants with well-developed taproots on one-third strength Schenk and Hildebrandt basal medium supplemented with 0.25 mg/L 1-naphthaleneacetic acid. When the plants were transferred to soil, about 30% of the regenerated plants developed into normal plants.

• Journal of Life Science
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• v.23 no.11
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• pp.1381-1387
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• 2013

The leaves and roots of Ligularia stenocephala, which are widely used as a food in Korea, were investigated for their antioxidant activities and cytotoxicity in vitro, and their hepatoprotective effect, alcohol detoxicant efficacy, and memory-enhancing property were investigated in vivo. The unique odor of the leaves was analyzed by GC-MS. Lipid peroxidation, superoxide anion formation, and DPPH radicals were inhibited remarkably by the extracts of the leaves and roots. The leaves of this edible plant significantly protected the hepatotoxicity induced by carbon tetrachloride and further diminished the blood alcohol content in mice. While the roots of this plant exhibited adequate cytotoxicity against four human tumor cell lines, especially against melanoma, the leaves revealed relatively weak activity. Both the leaves and the roots exerted an excellent ameliorating property on scopolamine-induced memory impairment in the passive avoidance task using an animal model. The hexane fraction of the leaves was analyzed by GC-MS, suggesting that a series of terpenoids may be odorous compounds in this plant.

• Korean Journal of Environmental Agriculture
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• v.40 no.2
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• pp.142-147
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• 2021

BACKGROUND: Agricultural use and pest control purposes of pesticides may lead to livestock products contamination. Thiodicarb and its degraded product, methomyl, are carbamate insecticides that protect soya bean, maize, fruit, and vegetables and control flies in animal and poultry farms. For maximum residue limit enforcement and monitoring, the JMPR residue definition of thiodicarb in animal products is the sum of thiodicarb and methomyl, expressed as methomyl. This residue definition was set to consider the fact that thiodicarb was readily degraded to methomyl in animal commodities. And therefore the simultaneous analytical method of thiodicarb and methomyl is required for monitoring in livestock products. METHODS AND RESULTS: The study was conducted using a quick, easy, cheap, effective, rugged, and safe (QuEChERS) method and HPLC-MS/MS to determine the thiodicarb and methomyl in livestock products. The limit of quantitation (LOQ) was 0.01 mg/kg for livestock products, including beef, pork, chicken, milk, and egg. The coefficient of determinations (r²) for the calibration curve were > 0.99, which was acceptable values for linearity. Average recoveries at spiked levels (LOQ, 10LOQ, and 50LOQ, n=5) in triplicate ranged from 73.2% to 102.1% and relative standard deviations (RSDs) were less than 10% in all matrices. CONCLUSION: The analytical method was validated for the performance parameters (specificity, linearity, accuracy, and precision) in livestock products to be acceptable by the CODEX guidelines.

• Journal of Soil and Groundwater Environment
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• v.23 no.6
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• pp.73-81
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• 2018

Inductively coupled plasma-mass spectrometry (ICP-MS), one of the most commonly used instruments for metal analysis, was used to determine total uranium in soil. The method was named as "Modified ASTM C1345-96". When comparing with ASTM C1345-96, digestion time (2~3 days) was shorten to 7 hours and the treatment in furnace was eliminated. In analyses of 26 field soil samples, there was a significant difference in the average concentration of total uranium between modified ASTM C1345-96 and ASTM C1345-96 (F : 6.22 > Fc : 4.03, significance level : 0.05, n=26). The average concentration of modified ASTM C1345-96 was 1.8 times larger than that of ASTM C1345-96. In addition, modified ASTM C1345-96 was compared with other acid digestion methods for soil including ISO 11466, Modified ISO 11466, US EPA-3051, US EPA-3051A and US EPA-3052 using a certificated reference material (SRM 2711a, NIST) and field soil samples with different level of organic matter content (1.6%, 5.8%, 10.6%). Modified ASTM C1345-96 showed the best accuracy of 93.01% for SRM 2711a. Also, modified ASTM C1345-96 showed the higher extraction rates than other digestion methods by 11~45%.

• Korean Journal of Veterinary Research
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• v.60 no.4
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• pp.209-213
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• 2020

This study examined the residue of dl-methylephedrine hydrochloride (MEP) on the muscle of pigs administered orally with MEP 12 g/ton feed for seven consecutive days. Twenty healthy cross swine were administered MEP. Four treated animals were selected arbitrarily to be sacrificed at 1, 2, 3, 4, and 5 days after treatment. MEP residue concentrations in the muscle were determined by liquid chromatography coupled with tandem mass spectrometry. The drug was extracted from muscle samples using 10 mM ammonium formate in acetonitrile followed by clean-up with n-hexane. The analyte was separated on an XBridgeTM hydrophilic interaction liquid chromatography column using 10 mM ammonium formate in deionized distilled water and acetonitrile. The correlation coefficient (R2) of the calibration curve was 0.9974, and the limits of detection and quantification were 0.05 and 0.15 ㎍/kg, respectively. The recoveries at three spiking levels were 94.5-101.2%, and the relative Standard Deviations was less than 4.06%. In the MEP-treated group, MEP residues on one day post-treatment were below the maximum residue limit in the muscle. The developed method is sensitive and reliable for the detection of MEP in porcine muscle tissues. Furthermore, it exhibits low quantification limits for animal-derived food products destined for human consumption.

• Korean Journal of Plant Resources
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• v.37 no.3
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• pp.225-234
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• 2024

Chinese lobelia (Lobelia chinensis Lour.) is an important medicinal plant that is used in traditional Chinese, Korean, and Japanese medicine. The goal of the current study was to develop an in vitro propagation technique for Lobelia chinensis. We have examined the effects of different media compositions on the regeneration of shoots from nodal cultures of Lobelia chinensis, including Murashige and Skoog (MS), Gamborg (B5), Schenk and Hildebrandt (SH), Woody plant (WPM), Chu (N6), and Nitsch and Nitsch (NLN) media. Similar to this, shoot regeneration was examined using MS medium of double (2.0), full (1.0), half (0.5), and quarter (0.25) strengths. The regeneration of shoots was also examined with additions of 0, 1, 3, 5, and 7% (w/v) sucrose to MS media. For axillary shoot regeneration, full-strength MS medium supplemented with 3% (w/v) sucrose was shown to be the most effective of all the evaluated factors. On this medium, nodal explants optimally regenerated 4.5 shoots per explant and subsequently shoots involved in rooting on the same medium. The regenerated plants possessed abundant phenolics, flavonoids, and DPPH, ABTS, and FRAP antioxidant activities. High performance liquid chromatographic examination (HPLC) of the regenerated plants revealed an accumulation of myricetin and catechin in higher amounts.