• Resources Recycling
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• v.32 no.3
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• pp.9-17
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• 2023

Efforts are currently underway to develop a method for efficiently recovering lithium from the cathode material of waste lithium iron phosphate batteries (LFP). The successful application of lithium battery recycling can address the regional ubiquity and price volatility of lithium resources, while also mitigating the environmental impact associated with both waste battery material and lithium production processes. The isomorphic substitution leaching process was used to recover lithium from spent lithium iron phosphate batteries. Lithium was leached by the isomorphic substitution of Fe²⁺ in LFP using a relatively inexpensive ferric chloride etching solution as a leaching agent. In the study, the leaching rate of lithium was compared using the ferric chloride etching solution at various multiples of the LFP molar ratio: 0.7, 1.0, 1.3, and 1.6 times. The highest lithium leaching rate was shown at about 98% when using 1.3 times the LFP molar ratio. Subsequently, to eliminate Fe, the leachate was treated with NaOH. The Fe-free solution was then used to synthesize lithium carbonate, and the harvested powder was characterized and validated. The surface shape and crystal phase were analyzed using SEM and XRD analysis, and impurities and purity were confirmed using ICP analysis.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.3
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• pp.235-245
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• 2008

Purpose: The HSV1-tk gene has been extensively studied as a type of reporter gene. In hepatocellular carcinoma (HCC), only a small proportion of patients are eligible for surgical resection and there is limitation in palliative options. Therefore, there is a need for the development of new treatment modalities and gene therapy is a leading candidate. In the present study, we investigated the usefulness of substrate, 2'-fluoro-2'-deoxy-1-${\beta}$-D-arabino-furanosyi-5-[$^{124/125}I$]iodo- uracil ([$I^{124/125}I$]FIAU) as a non-invasive imaging agent for HSV1-tk gene therapy in hepatoma model using small animal PET. Material and Methods: With the Morris hepatoma MCA cell line and MCA-tk cell line which was transduced with the HSV1-tk gene, in vitro uptake and correlation study between [$^{125}I$]FIAU uptake according to increasing numeric count of percentage of MCA-tk cell were performed. The biodistribution data and small animal PET images with [$^{124}I$]FIAU were obtained with Balb/c-nude mice bearing both MCA and MCA-tk tumors. Results:, Specific accumulation of [[$^{125}I$]FIAU was observed in MCA-tk cells but uptake was low in MCA cells. Uptake in MCA-tk cells was 15 times higher than that of MCA cells at 480 min. [$^{125}I$]FIAU uptake was linearly correlated (R2 =0.964, p =0.01) with increasing percentage of MCA-tk numeric cell count. Biodistribution results showed that [$^{125}I$]FIAU was mainly excreted via the renal system in the early phase. Ratios of MCA-tk tumor to blood acting were 10, 41, and 641 at 1 h, 4 h, and 24 h post-injection, respectively. The maximum ratio of MCA-tk to MCA tumor was 192.7 at 24 h. Ratios of MCA-tk tumor to liver were 13.8, 66.8, and 588.3 at 1 h, 4 h, and 24 h, respectively. On small animal PET, [$^{124}I$]FIAU accumulated in substantial higher levels in MCA-tk tumor and liver than MCA tumor. Conclusion: FIAU shows selective accumulation to HSV1-tk expressing hepatoma cell tumors with minimal uptake in normal liver. Therefore, radiolabelled FIAU is expected to be a useful substrate for non-invasive imaging of HSV1-tk gene therapy and therapeutic response monitoring of HCC.

• The Korean Journal of Nuclear Medicine
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• v.33 no.3
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• pp.298-305
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• 1999

Purpose: N-(3-[$^{18}F$]Fluoropropyl)-$2{\beta}$-carbomethoxy-$3{\beta}$-(4-iodophenyl)nortropane [$^{18}F$]FP-CIT) has been shown to be very useful for imaging the dopamine transporter. However, synthesis of this radiotracer is somewhat troublesome. In this study, we used a new method for the preparation of [$^{18}F$]FP-CIT to increase radiochemical yield and effective specific activity. Materials and Methods: [$^{18}F$]FP-CIT was prepared by N-alkylation of nor-${\beta}$-CIT (2 mg) with 3-bromo-1-[$^{18}F$]fluoropropane in the presence of $Et_3N$ (5-6 drops of $DMF/CH_3CN$, $140^{\circ}C$, 20 min). 3-Bromo-1-[$^{18}F$]fluoropropane was synthesized from $5{\mu}L$ of 3-bromo-1-trifluoromethanesulfonyloxypropane (3-bromopropyl-1-triflate) and $nBu_4N^{18}F$ at $80^{\circ}C$. The final compound was purified by reverse phase HPLC and formulated in 13% ethanol in saline. Results: 3-Bromo-1-[$^{18}F$]fluoropropane was obtained from 3-bromopropyl-1-triflate and $nBu_4N^{18}F$ in 77-80% yield. N-Alkylation of nor-${\beta}$-CIT with 3-bromo-1-[$^{18}F$]fluoropropane was carried out at $140^{\circ}C$ using acetonitrile containing a small volume of DMF as the solvents. The overall yield of [$^{18}F$]FP-CIT was 5-10% (decay-corrected) with a radiochemical purity higher than 99% and effective specific activity higher than the one reported in the literature based on their HPLC data. The final [$^{18}F$]FP-CIT solution had the optimal pH (7.0) and it was pyrogen-free. Conclusion: In this study, 3-bromopropyl-1-triflate was used as the precursor for the [$^{18}F$]fluorination reaction and new conditions were developed for purification of [$^{18}F$]FP-CIT by HPLC. We established this new method for the preparation of [$^{18}F$]FP-CIT, which gave high effective specific activity and relatively good yield.

• Clinical and Experimental Pediatrics
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• v.45 no.7
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• pp.847-854
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• 2002

Purpose : Long term hospitalized infants in neonatal intensive care units(NICUs) are prone to systemic infection. It is important to differentiate systemic candidiasis from systemic bacterial infection early in the course. Thus, in this study, we have compared clinical characteristics of systemic candidiasis and systemic bacterial infection, in premature low birth weight infants. Methods : Retrospective chart review of the medical records of 20 patients with systemic candidiasis and 23 patients with systemic bacterial infection was performed. Results : Among the risk factors of systemic candidiasis, total parenteral nutrition(TPN), the use of broad spectrum antibiotics, central catheter insertion, endotracheal intubation and the use of H2 blockers were more frequent in neonates with systemic candidiasis than neonates with systemic bacterial infection. Apnea with bradycardia developed more frequently in neonates with systemic candidiasis compared with systemic bacterial infection(75% vs 39%). In laboratory findings at symptom onset, seven cases(35%) of systemic candidal infections and two cases(9%) of systemic bacterial infections showed leukopenia and thrombocytopenia(P=0.03). Blood was the most frequent isolation site of candida and bacteria. Conclusion : In neonates with systemic candidiasis, apnea with bradycardia, pneumonia and thrombocytopenia were prone to develop more frequently. The use of TPN, antibiotics and central catheters was strongly associated with systemic candidiasis. Empirical treatment with antifungal agent should be considered in critically ill neonates with above findings.

• Korean Journal of Food Science and Technology
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• v.49 no.6
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• pp.676-684
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• 2017

The present study aimed to examine the hepatoprotective effects of ethanol extracts from steam-dried ginseng berry (SGBE) in both $\text\tiny{D}$-Galactosamine/Lipopolysaccharide ($\text\tiny{D}$-GalN/LPS)-sensitized mice and in vitro models. Our results clearly demonstrated that SGBE significantly reduced the level of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and lactate dehydrogenase in blood, and $TNF{\alpha}$ was normalized in 8 h after the treatment with $\text\tiny{D}$-GalN/LPS. Coincidently, major organs remained unimpaired when compared to $\text\tiny{D}$-GalN/LPS control group. Moreover, p38, which stimulates expression of NAFLD-associated cytokines, was markedly inhibited when treated with SGBE. In vitro analysis revealed that the main components of SGBE, linoleic acid and ginsenoside Re/Rd, may play a role in protecting liver from $\text\tiny{D}$-GalN/LPS-induced toxicity. Finally, we concluded that SGBE may be a promising therapeutic agent for preventing damage to the liver.

• Korean Journal of Cognitive Science
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• v.12 no.3
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• pp.29-46
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• 2001

This study attempted to demonstrate that the integration of the two premises in linear syllogism is mediated by the middle term the term that is repeated in the two premises. In Experiment 1. we examined whether representing the middle term is more important than representing the end terms. We asked a question to each premise. Depending on the order of the questions either the two end terms or the middle term became the answer in both premises. Participants solved the problems better when the middle term became the answer suggesting that it is more important to represent the middle term than the end terms. In Experiment 2 we examined whether additional processing is needed for the integration beyond establishing co-referential link through the middle term. We pronominalized the middle term in the second premise and provided two kinds of information to disambiguate the pronoun. In the direct information condition we provided information about who the pronoun is whereas in the indirect information condition we provided information about the relative location of the pronoun. Participants solved the problems more quickly in the indirect information condition than in the direct information condition indicating that mere co-referential link was not enough and that the relative location of the middle term needs to be computed for the integration of the two premises.

• Journal of Food Hygiene and Safety
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• v.35 no.5
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• pp.503-512
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• 2020

To enhance the usability of puffed rice, we evaluated the quality characteristics and antioxidant activity of vinegar made with puffed rice and lemon balm. First, puffed rice containing lemon balm extracts was fermented for alcohol production. The alcoholic fermented liquid was adjusted to an alcohol content of 6% and an initial acidity of 2% for vinegar fermentation. The pH and alcohol content of the lemon balm vinegar decreased overall as fermentation progressed. The total acidity was 5.20±0.01% (2.0% lemon balm) to 5.80±0.01% (0.0% lemon balm) on the 15th day of fermentation, and the total acidity was slightly lower as the amount of added lemon balm was increased. Citric, succinic, and acetic organic acids were detected in the vinegar and the acetic acid content was highest at 4.81% to 5.37% on the 15th day of fermentation. We found that the total polyphenol and total flavonoid content of the lemon balm vinegar increased as we added lemon balm, and the content on the 15th day of fermentation was 179.4±4.5 (0.0% lemon balm) - 340.8±2.6 mg/kg (2.0% lemon balm) and 1.5±0.3 (0.0% lemon balm) - 31.7±0.3 mg/kg (2.0% lemon balm), respectively. The higher the amount of lemon balm added, the higher the DPPH radical scavenging activity, the FRAP (reducing power), and the ABTS radical scavenging activity. Moreover, those activities after 2.0% lemon balm treatment were 82.99±0.61%, 1.08±0.01 abs., and 87.67±0.68%, respectively, on the 15th day of fermentation. These results suggest that vinegar with added lemon balm may be used as an antioxidant agent.

• Journal of Life Science
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• v.28 no.10
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• pp.1156-1162
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• 2018

To investigate the anti-thrombotic activities of the lotus (Nelumbo nucifera Gaertner), various hot-water extracts were prepared from the leaf, pod of seed (PS), seed, embryo of seed (ES), root, and the node of root (NR) of the lotus. The highest extraction ratio was found in the NR (20.3%), followed by the seed, root, leaf, ES, and PS. These extracts had pH and acidity levels ranging from 5.6~6.5 and 0.06~0.20%, respectively. The seed extract showed 70% brix, whereas the leaf and PS extracts showed less than 0.1% brix. The highest contents of total polyphenol (179.7 mg/g), total flavonoids (161.4 mg/g), and reducing sugar (161.4 mg/g) were observed in the leaf extract, and the highest total sugar content (873.0 mg/g) in the seed extract. Anti-coagulation assay of the extracts of NR, leaf, and PS showed strong activities. In particular, at a concentration of 5 mg/ml, the PS extract had 15-fold extended thrombin, prothrombin, and activated partial thromboplastin times. However, only the ES extract showed activities inhibitory to platelet aggregation, with treatment with 0.25 mg/ml of ES extract decreasing platelet aggregation to 25.1%, a reduction comparable to that effected by aspirin. The extracts other than the seed extract showed no hemolysis activities against human RBC at treatments of up to 1 mg/ml. These results suggest that the NR, PS, seed, and ES, all byproducts of the lotus agriculture industry, have high potential as novel sources of anti-thrombotic agent.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.694-705
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• 2017

The aim of this study was to isolate and identify marine bacterium with anti-methicillin-resistant Staphylococcus aureus (MRSA) activity, and to purify the anti-MRSA compound, as well as to determine its activity and synergistic effects. Among the marine bacteria isolated in this study, the YJ-1 isolate had the strongest anti-MRSA activity. The YJ-1 isolate was identified on the basis of its biochemical characteristics and an analysis of 16S rRNA gene sequences. The YJ-1 isolate showed over 99.2% homology with Pseudomonas stutzeri, and was designated as a Pseudomonas sp. YJ-1. The optimal culture conditions were $25^{\circ}C$ and initial pH 7.0. For the purification of the anti-MRSA compounds, the YJ-1 was cultured in Pa PES-II medium, and the culture filtrates were extracted by ethyl acetate, hexane, and 80% MeOH. The 80% MeOH fraction was separated by a $C_{18}$ ODS column, silica gel chromatography and a reverse phase HPLC, to yield three anti-MRSA agents, the MR1, MR2, and MR3 compounds. When the MR1 compound of $250{\mu}g\;mL^{-1}$ concentration was applied to the MRSA cells, over 95% of bacterial cells was killed within 48 hr. Compared with vancomycin and ampicillin, the MR1 compound showed significant anti-MRSA activity. In addition, the anti-MRSA activity was increased by dose and time dependent manners. Furthermore, the combination of an MR1 compound with vancomycin produced a more rapid decrease in the MRSA cells than did the MR1 compound alone. Taken together, our results suggest that the Pseudomonas sp. YJ-1 and its anti-MRSA compounds could be employed as a natural antibacterial agent in MRSA infections.

• Applied Chemistry for Engineering
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• v.33 no.2
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• pp.173-178
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• 2022

A lateral flow immunoassay (LFIA) method using carbon nanodot@silica as a signaling material was developed for analyzing the concentration of retinol-binding protein 4 (RBP4), one of the lung cancer biomarkers. Instead of antibodies mainly used as bioreceptors in nitrocellulose membranes in LFIA for protein detection, aptamers that are more economical, easy to store for a long time, and have strong affinities toward specific target proteins were used. A 5' terminal of biotin-modified aptamer specific to RBP4 was first reacted with neutravidin followed by spraying the mixture on the membrane in order to immobilize the aptamer in a porous membrane by the strong binding affinity between biotin and neutravidin. Carbon nanodot@silica nanoparticles with blue fluorescent signal covalently conjugated to the RBP4 antibody, and RBP4 were injected in a lateral flow manner on to the surface bound aptamer to form a sandwich complex. Surfactant concentrations, ionic strength, and additional blocking reagents were added to the running buffer solution to optimize the fluorescent signal off from the sandwich complex which was correlated to the concentration of RBP4. A 10 mM Tris (pH 7.4) running buffer containing 150 mM NaCl and 0.05% Tween-20 with 0.6 M ethanolamine as a blocking agent showed the optimum assay condition for carbon nanodot@silica-based LFIA. The results indicate that an aptamer, more economical and easier to store for a long time can be used as an alternative immobilizing probe for antibody in a LFIA device which can be used as a point-of-care diagnosis kit for lung cancer diseases.