• Bulletin of the Korean Chemical Society
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• v.20 no.2
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• pp.237-240
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• 1999

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.92.2-92.2
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• 2013

The design and chemical synthesis of multifunctional nanomaterials have been providing potential applications in biomedical fields such as molecular imaging and drug delivery. Recently, bio-derived and/or synthetic nanostructured materials capable of modulating the immune system have been also issues of interest in immunology-related nanomedicine fields. In this talk, the recent research results on the development of nanostructured materials for enhanced immunity would be presented. I will introduce the chemical strategy for the combination of nanostructured materials and bioactive compounds to improve both anti-cancer immunity and vaccine delivery efficiency.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.8 no.2
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• pp.113-118
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• 2022

Gadolinium neutron capture therapy (Gd-NCT) is a precision radiation therapy that kills cancer cells using the neutron capture reaction that occurs when ¹⁵⁷Gd hits thermal neutrons. ¹⁵⁷Gd has the highest thermal neutron capture cross section of 254,000 barns among stable isotopes in the periodic table. Another stable isotope, ¹⁵⁵Gd, also has a high thermal neutron trapping area (~ 60,700 barns), so gadolinium that exists in nature can be used as a Gd-NCT drug. Gd-NCT is a mixed kinetic energy of low-energy and high-energy ionizing particles, which can be uniformly distributed throughout the tumor tissue, thereby solving the disadvantage of heterogeneous dose distribution in tumor tissue. The Gd complexes of small-sized molecule are widely used as contrast agents for magnetic resonance imaging (MRI) in clinical practice. Therefore, these compounds can be used not only for diagnosis but also therapy when considering the concept of Gd-NCT. This multifunctional trial can look forward to new medical advance into NCT clinical practices. In this review, we introduce gadolinium compounds suitable for Gd-NCT and describe the necessity of image guided Gd-NCT.

• Journal of the Korean Chemical Society
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• v.27 no.1
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• pp.46-52
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• 1983

Selective reduction of halide (Br, I) with lithium borohydride in halogen compounds containing chloro, nitro, ester and nitrile groups was achieved satisfactorily. 1-Bromo-4-chlorobutane was reduced to 1-chlorobutane in 96% yield and the reduction of p-nitrobenzyl bromide gave p-nitrotoluene in 98% yield. However, the selectivity on the reduction of ethyl 3-iodopropionate and 4-bromobutyronitrile required the presence of equimolar pyridine to give good yield of ethyl propionate (93%) and n-butyronitrile (88%), respectively. In competitive reduction of 1-bromoheptane and 2-bromoheptane, lithium borohydride reduced 1-bromoheptane preferentially in the molar ratio of 93:7.

• Food Science of Animal Resources
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• v.40 no.6
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• pp.863-880
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• 2020

Studies conducted in the past decade related to the use of natural antioxidants in meat products revealed the prevalent use of plant-based antioxidative materials added as powders, extracts, or dried or raw materials to meat products. The amount of antioxidative materials varied from 7.8 ppm to 19.8%. Extracts and powders were used in small amounts (ppm to grams) and large amounts (grams to >1%), respectively. Antioxidative materials used in meat products are mainly composed of phenolic compounds and flavonoids, which are able to inhibit lipid peroxidation of meat products, thereby preserving meat quality. However, the main ingredients used in processed meat products are the traditional additives, such as sodium erythorbate, sodium hydrosulfite, and synthetic antioxidants, rather than natural antioxidants. This difference could be attributed to changes in the sensory quality or characteristics of meat products using natural antioxidants. Therefore, novel research paradigms to develop meat products are needed, focusing on the multifunctional aspects of natural antioxidants.

• Journal of Food Hygiene and Safety
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• v.23 no.1
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• pp.68-72
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• 2008

Antimicrobial stability of grape seed extract ($ActiVin^{TM}$), pine bark extract ($Pycnogenol^{(R)}$), and oleoresin rosemary ($Herbalox^{(R)}$) on the growth of Aeromonas hydrophila was investigated in cooked ground beef. When compared to the control, the populations of A. hydrophila were most effectively reduced by 4.06 log CFU/g for 1% $Pycnogenol^{(R)}$ added after cooking at 10 days of refrigerated storage, followed by 3.06 log CFU/g for 1% $Pycnogenol^{(R)}$ added before cooking and 1.36 log CFU/g for $ActiVin^{TM}$. Bacteriostatic and bactericidal activities were observed for $Pycnogenol^{(R)}$ added before and after cooking, respectively. $Pycnogenol^{(R)}$ consists of heat-labile and heat-stable compounds. $ActiVin^{TM}$ and $Pycnogenol^{(R)}$ could be considered for use as multifunctional preservatives in meat and meat products.

• Current Applied Physics
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• v.18 no.12
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• pp.1473-1479
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• 2018

Recently multiferroic materials have attract great interest for the applications on memorial, spintronic and magneto-electric sensor devices for their spontaneous magneto-electric coupling properties. Research and development of the various kinds of multiferroics are indispensable factor for a new generation multifunctional materials. In this research, mechanical, electronic, magnetic and nonlinear optical properties of La modified $BiLaFe_2O_6$ (BLFO) and Mn modified $Bi_2FeMnO_6$ (BFMO) were studied as new members of multiferroic $BiFeO_3$ (BFO) series by first-principles calculations, and compared with the pure BFO to discover the optimized properties. Our results show that BLFO and BFMO have good mechanical stability as revealed by elastic constants that satisfy the stability criteria. All these compounds exhibit anisotropic and ductile nature. The enhanced properties by La and Mn substitution, such as increased hardness, improved magnetism, decreased band gap and comparable second harmonic generation responses reveal that the new multiferroic members of BLFO and BFMO would get wider application than their BFO counterpart. Our study is expected to providing an appropriate mechanical reference data as guidance for engineering of high efficiency multifunctional devices with the BFO series.

• Journal of Life Science
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• v.9 no.1
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• pp.40-44
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• 1999

Glutathione S-transferase (GST) is a multifunctional protein that catalyzes the catalyzes the conjugation of glutathione with electrophilic compounds. It exists in a variety of isoenzy-matic froms with a wide range of substrate specificity and plays a pivotal role in detoxification of various drugs. In order to elucidate the GST-${\pi}$'s involvement of multidrug resistance (MDR) in drug-resistant tumor cell lines, we determined GST-${\pi}$ content by "1 step sandwich method". Consequently, adriamycin resistant cells of MCF-7 (MCF-7/ADM) have 7-fold increase of GST-${\pi}$ content than that of MCF-7 cells, while its {TEX}$IC_{50}${/TEX} was 116-fold greater than parent cell line. By northrn blotting, we compared whether MCF-7/ADM cells express GST-${\pi}$ mRNA. The GST-${\pi}$ mRNA expression in these cells was not inducible, but constitutive when treated for 24 h with a concentration of 0, 20, 200, and 2000 nM of adriamycin, respectively. Taken together, these results suggest that GST-${\pi}$ may not be directly associated with multidrug resistance in these human cancer cell lines.ell lines.

• Journal of Microbiology and Biotechnology
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• v.16 no.5
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• pp.764-770
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• 2006

Dihydrochalcomycin (GERI-155), produced by Streptomyces sp. KCTC-0041BP isolated from Korean soil, is a 16-membered macrolide antibiotic consisting of two deoxysugar moieties at C-5 and C-20 positions of a branched lactone ring. The cloning and sequencing of a gene cluster for dihydrochalcomycin biosynthesis revealed a 63-kb nucleotide region containing 25 open reading frames (ORFs). The products of all of these 25 ORFs playa role in dihydrochalcomycin biosynthesis and self-resistance against the compounds synthesized. At the core of this cluster lies a 39.6-kb polyketide synthase (PKS) region encoding eight modules in five giant multifunctional protein-coding genes (gerSI-SV). The genes responsible for the biosynthesis of deoxysugar moieties, D-chalcose and D-mycinose, and their modification and attachment were found on either side of this PKS region. The involvement of this gene cluster in dihydrochalcomycin biosynthesis was confirmed by disruption of the dehydratase (DH) domain in module 3 of the PKS gene and by metabolite analysis.

• Membrane and Water Treatment
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• v.5 no.2
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• pp.123-146
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• 2014

Safe water has becoming a competitive resource in many parts of the world due to increasing population, prolonged droughts, climate change etc. The development of economical and stable materials and methods for providing the fresh water in adequate amounts is the need of the water industry. Nanomaterials have unique characteristics e.g., large surface areas, size, shape, and dimensions etc. that make them particularly attractive for removing various contaminants from polluted waters. Nanotechnology based multifunctional and highly efficient membrane processes are providing affordable solutions in the new era that do not rely on large infrastructures or centralizes systems. The objective of the current study is to review the possible applications of the membrane based nanomaterials/composites for the removal of various contaminations from polluted waters. The article will briefly overview the availability and practice of different nanomaterials based membranes for removal of bacteria and viruses, organic compounds and inorganic solutes etc. present in surface water, ground water, seawater and/or industrial water. Finally, recommendations are made based on the current practices of nanofiltration membranes in water industry for a stand-alone membrane filtration system in removing various types of contaminants from polluted waters.