• Journal of the Korean Chemical Society
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• v.33 no.3
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• pp.315-320
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• 1989

A method was presented for the analysis of trace metals in iron oxide ore. The method utilized ammonium pyrrolidinedithiocarbamate (APDC)-methyl isobutyl ketone (MIBK) extraction procedure and analysis by atomic absorption spectroscopy (AA). Citrate at pH $8{\sim}10$ for the determination of Co, Ni and Cu or tiron at pH $6{\sim}7$for the determination of Mn and Cu was added as a masking agent to prevent extraction of Fe(III) into the organic phase. Reduction of solubility of MIBK in water was achieved by addition of NaCl as a salting-out agent. Back extraction of the MIBK extracts with aqueous $HNO_3$ was also studied to increase the stability of metal extracts.

• The Korean Journal of Nuclear Medicine
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• v.33 no.4
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• pp.381-387
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• 1999

Purpose: The International Labor Organization (ILO) has established an international standard for chest X-ray diagnosis of pneumoconiosis since 1980. However, there is a need for improved diagnosis and staging in occupational disease. We evaluated Ga-67 citrate scintigraphy quantitatively and correlated the scintigraphic findings with pulmonary function tests and chest X-ray results. Materials and Methods: Twenty-five patients underwent whole body scintigraphy with additional chest and abdomen images 48 hrs after intravenous injection of 185 MBq of Ga-67 citrate. Ten normal controls were also studied. Regions of interest (ROI) were drawn on the posterior image to measure counts from the liver and lungs (Lung/Liver Ratio). Results: L/L ratio according to the stages of chest X-ray classification were as follows; stage 0 (normal, n=10): $0.3948{\pm}0.0692$, stage 1 (n=10): $0.5763{\pm}0.1537$, stage 2 (n=11), $0.6849{\pm}0.1459$, stage 3 (n=4) $0.9913{\pm}0.0712$. There was a significant correlation between the scintigraphic L/L ratio and the X-ray stage (r=0.618, p<0.05). However, no significant correlation between L/L ratio and pulmonary function tests were observed (p>0.05). Conclusion: Quantitative Ga-67 scintigraphy can be a useful method for staging of silicosis. However, it is not a method to assess pulmonary functional impairment.

• Proceedings of the KIEE Conference
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• 2006.10a
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• pp.42-43
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• 2006

High Tc superconducting with a BiSrCaCuO was prepared by the citrate method. The solid precursor produced by the dehydration of the gel at $120^{\circ}C$ for 12h is not in the a morphous state as expected but in a crystalline state. X -ray diffraction peaks of nearly the same angular position as the peaks of high Tc phase were observed in the precursor.

• BMB Reports
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• v.33 no.5
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• pp.396-401
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• 2000

A differential display method is used to identify novel genes whose expression is affected by treatment with ferric ammonium citrate (FAC) or desferrioxamine (DFO), an iron chelating agent in the human hepatoblastoma cell line (HepG2). These chemicals are known to deplete or increase the intracellular concentration of iron, respectively. Initially, we isolated seventeen genes whose expressions are down- or up regulated by the treatment of the chemicals, as well as their four differentially expressed genes that are designated as clone-1, -2, -3, and -4. These are further characterized by cDNA sequencing and Northern blot analysis. Through the cDNA sequencing, as well as comparing them to genes published using the NCBI BLAST program, we identified the sequence of the clone-1 that is up-regulated by the treatment of DFO. It is identical to the human insulin-like growth factor binding protein-1 (IGFBP-1). This suggests that the IGFBP-1 gene in the HepG2 cell is up-regulated by an iron depletion condition. Also, the expression of the clone-3 and -4 is up-regulated by FAC treatment and their eDNA sequences are identical to the human ferritin-fight chain and human NADH-dehydrogenase, respectively. However, the sequence of the clone-2 has no significant homology to any other known gene. Therefore, we suggest that changes of the cellular iron level in the HepG2 cell affects the transcription of cellular genes. This includes human IGFBP-1, ferritin-fight chain, and NADH-dehydrogenase. Regulation of these gene expressions may have an important role in cellular functions that are related to cellular iron metabolism.

• The Korean Journal of Food And Nutrition
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• v.22 no.1
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• pp.20-28
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• 2009

According to traditional oriental medicine, only non-coagulated native deer blood is said to be effective, and coagulated deer blood is ineffective. Thus, a drying and tablet-producing method for deer blood was developed to maintain its physiological and therapeutic activity, and so that after drying, it can be redissolved and protected from coagulation. Proteases such as trypsin, pepsin, chymotrypsin, and aminopeptidase were added to the deer blood indicating that it coagulated in an hour, as shown by the reference. Wax gourd extract, which is high in protease, was added to the blood resulting in anticoagulation for 31 hours. Also, additions of 1% EDTA, 0.38% sodium citrate, 0.16% calcium oxalate, 1.2% ethanol, and 0.006% heparin to the deer blood resulted in anticoagulation for 1 hour, 4 hours, 2 hours, 1 hour, and 31 hours, respectively. In an experiment using 0.19% sodium citrate plus 1% wax gourd extract, and 0.006% heparin plus 1% wax gourd extract, anticoagulation was maintained for up to 72 hours. However, since heparin can not be used in food, the deer blood tablet was made with the addition of 0.19% sodium citrate and 1% wax gourd extract, followed by freeze drying. The dissolution rate for the tablet manufactured in this manner was 96.7%. And the dissolution rates for spray-dried deer blood, vacuum-dried deer blood, and marketed deer blood tablets were 85%, 81%, and 25.5%, respectively. The composition of the tablet produced from the freeze-dried deer blood was 56.4% protein, 18.7% lactose, 1.2% amino acids, 1.0% glucose, 0.7% lipids, 180 mg/100 g of iron, 13 mg/100 g of potassium, 39.1 mg/100 g of calcium, 480 mg/100 g of sodium, 368 mg/100 g of chloride, each.

• KSBB Journal
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• v.20 no.3
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• pp.215-219
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• 2005

Production of alkaline pretense by Bacillus clausii I-52 was optimized by experimental design methods. Among 7 medium components, three (wheat flour, sodium citrate, sodium carbonate) were selected as components affecting the pretense activity significantly by Plackett-Burman methods. Furthermore the ranges of effective concentrations were determined by Box-Behnken methods. The objective function describing the alkaline pretense production was obtained and optimum concentration of 3 components was determined by using response-surface methods (RSM). Theoretical maximum production was 74000 U/mL (Wheat flour: 0 g/L, Sodium citrate: 5 g/L, Sodium carbonate: 10 g/L). With the optimized medium composition, 92000 U/mL alkaline protease was produced experimentally, resulting in $90\%$ increase compared to before-optimization production (49000 U/mL).

• Resources Recycling
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• v.16 no.6
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• pp.10-19
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• 2007

The mechanical process followed by hydrometallurgical treatment has been developed in order to recover cobalt and lithium from spent lithium ion battery. In the previous study, a citrate precursor combustion process to prepare cathodic active materials from the leaching solution was elucidated. Resynthesis of electrode materials should be more valuable in spent battery recycling. Conventional slurry mixing of $LiCoO_2$ and carbon cannot make uniform distribution, and therefore the cathode cannot reach the theoretical charge-discharge capacity and is easily degraded during the charge-discharge cycling. In this study, ultra-fine $LiCoO_2$ powders has been prepared by modification of the combustion process and fabricated the enhanced cathode by modification of mixing method of $LiCoO_2$ and carbon added.

• Journal of Life Science
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• v.20 no.7
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• pp.1041-1046
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• 2010

Phytoextraction is a technique which uses plants to clean up metal-contaminated soils. Recently, various chelating agents were introduced into this technique to increase the bioavailability of metals in soils. Even though the technique is an economic and environment-friendly method, this cannot be applied in highly metal-contaminated areas because plants will not normally grow in such conditions. Therefore, this research focuses on identifying chelating agents which are biodegradable and applicable to highly metal-contaminated areas. Alunimum (Al) as a target metal and cysteine (Cys), histidine (His), citrate, malate, oxalate, succinate, and ethylenediamine (EDA) as biodegradable chelating agents were selected. Ethylenediamine tetraacetic acid (EDTA) was used as a comparative standard. Plants were grown on agar media containing various chelating agents with Al to analyze the effect on plant growth. His slightly diminished the inhibitory effect of Al on root growth of plants, whereas, Cys, citrate, malate, oxalate, and succinate did not show significant effects. Both EDTA and EDA strongly diminished the inhibitory effect of Al on root growth. The effect of EDA is correlated with decreased Al uptake into the plants. In conclusion, as a biodegradable chelating agent, EDA is a good candidate for highly Al-contaminated areas.

• Biomolecules & Therapeutics
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• v.23 no.5
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• pp.486-492
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• 2015

Drug metabolism mostly occurs in the liver. Cytochrome P450 (CYP) is a drug-metabolizing enzyme that is responsible for many important drug metabolism reactions. Recently, the US FDA and EU EMA have suggested that CYP enzyme induction can be measured by both enzymatic activity and mRNA expression. However, these experiments are time-consuming and their interassay variability can lead to misinterpretations of the results. To resolve these problems and establish a more powerful method to measure CYP induction, we determined CYP induction by using luminescent assay. Luminescent CYP assays link CYP enzyme activity to firefly luciferase luminescence technology. In this study, we measured the induction of CYP isozymes (1A2, 2B6, 2C9, and 3A4) in cryopreserved human hepatocytes (HMC424, 478, and 493) using a luminometer. We then examined the potential induction abilities (unknown so far) of mesalazine, a drug for colitis, and mosapride citrate, which is used as an antispasmodic drug. The results showed that mesalazine promotes CYP2B6 and 3A4 activities, while mosapride citrate promotes CYP1A2, 2B6, and 3A4 activities. Luminescent CYP assays offer rapid and safe advantages over LC-MS/MS and qRT-PCR methods. Furthermore, luminescent CYP assays decrease the interference between the optical properties of the test compound and the CYP substrates. Therefore, luminescent CYP assays are less labor intensive, rapid, and can be used as robust tools for high-throughput CYP screening during early drug discovery.

• KSBB Journal
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• v.14 no.4
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• pp.422-428
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• 1999

A transformat Alcaligence eutrophus GA5 harboring phbC gene from A. latus was cultivated for production of Poly(3-hydroxybutyrate-4-hydroxybutyrate)[P(3HB-4HB)] containing high molar fraction of 4-hydroxybutyrate(4HB)] containing high molar fraction of 4-hydroxybutyrate(4HB). Transformation did not influenced significantly on total cell growth, on total cell growth, concentration, and content of P(3HB-4HB), however, significantly influenced on 4HB molar fraction in P(3HB-4HB) increasing from 12.3 to 23.5 mol% after 48 h cultivation in two-stage using 1.0%(W/V) of ${\gamma}$-butyrolactone as a precursor compare to parent strain. Above increment may be due to the accelerated polymerization between 3HB and 4HB converted from precusor compound by amplified phbC gene. Citrate increased remarkbly total cell mass and P(3HB-4HB) concentration, but did not influenced on the molar fraction of 4HB, meanwhile, magnesium ion influenced on P(3HB-4HB) concentration and 4HB molar fraction significantly. The two-stage cultivation method was modified, in such a way minimizing P(3HB) accumulated inside of cell grown at first-stage, consquently, 26.3% of P(3HB-4HB) containing 61.0 mol% of 4HB fraction was obtained after 72hr. Furthermore, semi-homopolymeric P(4HB) containing 92.0 mol% of 4Hb was obtained, and its structure was confirmed by $^1$H-NMR.