• Title/Summary/Keyword: Biological agent

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Induction of Apoptosis by Ethanol Extract of Lythrum anceps (Koehne) Mak ino in Human Leuk emia U937 Cells (인체백혈병 U937 세포에서 부처꽃 에탄올추출물에 의한 apoptosis 유도)

  • Eun Jung Ahn;Chul Hwan Kim;Jin-Woo Jeong;Buyng Su Hwang;Min-Jeong Seo;Kyung-Min Choi;Su Young Shin
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2020.08a
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    • pp.77-77
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    • 2020
  • Purple loosestrife-Lythrum anceps (Koehne) Makino is a herbaceous perennial plant belonging to the Lythraceae family. It has been used for centuries in Korea and other Asian traditional medicine. It has been showed pharmacological effects, including anti-oxidant and anti-microbial effects. However, the mechanisms underlying its anti-cancer mechanisms are not yet understood. In this study, we investigated the mechanism of apoptosis signaling pathways by ethanol extract of Lythrum anceps (Koehne) Makino (ELM) in human leukemia U937 cells. Treatment with ELM significantly inhibited cell growth in a dose-dependent manner by inducing apoptosis, as evidenced by the formation of apoptotic bodies (ApoBDs), DNA fragmentation and increased populations of sub-G1 ratio. Induction of apoptosis by ELM was connected with up-regulation of death receptor (DR) 4 and DR5, pro-apoptotic Bax protein expression and down-regulation of anti-apoptotic Bcl-2 protein, and inhibitor of apoptosis protein (IAP) family proteins (XIAP, cIAP-1, survivin), depending on dosage. This induction was associated with Bid truncation, mitochondrial dysfunction, proteolytic activation of caspases (-3, -8 and -9) and cleavage of poly(ADP-ribose) polymerase protein. Therefore, our data indicate that ELM suppresses U937 cell growth by activating the intrinsic and extrinsic apoptosis pathways, and thus may have applications as a potential source for an anti-leukemic chemotherapeutic agent.

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Bacillus vallismortis EXTN-1-Mediated Growth Promotion and Disease Suppression in Rice

  • Park Kyung-Seok;Paul Diby;Yeh Wan-Hae
    • The Plant Pathology Journal
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    • v.22 no.3
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    • pp.278-282
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    • 2006
  • Bacillus vallismortis EXTN-1, a biocontrol agent in cucumber, tomato and potato was tested in rice pathosystem against rice fungal pathogens viz. Magnaporthe grisea, Rhizoctonia solani and Cochliobolus miyabeanus. Apart from increasing the yield in the bacterized plants (11.6-12.6% over control), the study showed that EXTN1 is effective in bringing about disease suppression against all the tested fungal pathogens. EXTN-l treatment resulted in 52.11% reduction in rice blast, 83.02% reduction in sheath blight and 11.54% decrease in brown spot symptoms. As the strain is proven as an inducer for systemic resistance based on PR gene expression in Arabidopsis and tobacco models, it is supposed that a similar mechanism works in rice, bringing about disease suppression. The strain could be used as a potent biocontrol and growth-promoting agent in rice cropping system.

Synthesis and Conformation of Novel 3'-Branched Threosyl-5'-Deoxyphosphonic Acid Nucleoside Analogues

  • Shen, Guang Huan;Kang, Lien;Kim, Eun-Ae;Lee, Won-Jae;Hong, Joon-Hee
    • Bulletin of the Korean Chemical Society
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    • v.33 no.8
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    • pp.2574-2580
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    • 2012
  • The discovery that threosyl phosphonate nucleoside (PMDTA, $EC_{50}=2.53{\mu}M$) is a potent anti-HIV agent has led to the synthesis and biological evaluation of 5'-deoxy versions of threosyl phosphonate nucleosides. In the present study, (E)-3'-phosphonoalkenyl and 3'-phosphonoalkyl nucleoside analogues 13, 16, 20 and 23 were synthesized from acetol and tested for anti-HIV activity and cytotoxicity. The adenine analogue 16 was found to exhibit moderate in vitro anti-HIV-1 activity ($EC_{50}=22.2{\mu}M$).

A Study on the Fermentation Characteristics of Garbages by the C/N Ratio Control using Kudzu Creeper and Sawdust (칡넝쿨 및 톱밥을 이용한 C/N비 조절에 따른 음식물찌꺼기의 발효특성에 관한 연구)

  • 박진식;안철우;문추연
    • Journal of environmental and Sanitary engineering
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    • v.15 no.3
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    • pp.24-30
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    • 2000
  • In this study, to determine the optimum fermentation process for the feed production of food wastes and estimate the practical value of fermented feed using kudzu creeper and sawdust as bulking agent. This study considered initial C/N ratio control as the fermentation process variables. The result are summarized as follows. Minimum water contents of byproducts in the fermentation feed production showed 39%(kudzu), 37%(sawdust) at the C/N ratio 25 and 45%(kudzu, sawdust) at the C/N ratio 35. Temperature variations in the fermentation feed production at the C/N ratio 25 indicated $68^{\circ}C$(kudzu), $70^{\circ}C$(sawdust). Optimum condition of fermentation process of water content, C/N ratio and permeability (porous structure of the mixture). For optimum fermentation gravitationally dewatered garbage, the proper mixing ratios of kudzu(moisture contents : 17.3%) and sawdust(moisture contents : 13.2%) were 41% and 39%, respectively. Major biological reaction in the aerobic fermentation feed production occurred during 12~24hrs.

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Radiation Effects on Polypropylene for Biomedical Application (Polypropylene의 방사선멸균에있어 제 첨가제들에 의한 영향)

  • Khang, Gil-Son;Lee, Hai-Bang
    • Proceedings of the KOSOMBE Conference
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    • v.1995 no.11
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    • pp.134-137
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    • 1995
  • Studies on the formulations of the additives such as antioxidants, crosslinking agent, and trans-stilbeneoxide (StO) with polypropylene (PP) have been carried out to improve the resistance of gamma radiation sterilization. The irradiated PP and ethylene-propylene copolymers samples with control and additives were characterized by mechanical tester, colorimetry, and Fourier transform infrared spectroscopy with total attenuated reflectance mode (FTIR-ATR). Crosslinking agent and StO formulated PP showed remarkable radiation resistance and minimum discoloration. Also, radiation resistance of ethylene propylene copolymers with 3% of ethylene contents was better than that of PP homopolymers in the case of no additives. The proposed mechanisms of radiation stabilization with additives are also discussed.

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Control of Large Patch Catch by Rhizoctonia solani AG2-2 by Combined Application of Antagonists and Chemicals (길항균과 농약의 조합처리에 의한 갈색퍼짐병(라지패취) 방제)

  • 심규열;김희규
    • Asian Journal of Turfgrass Science
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    • v.13 no.3
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    • pp.131-138
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    • 1999
  • A synergistic effect of biocontrol agent and chemicals on control of the large patch on turfgrass caused by Rhizoctonia solani AG2-2 was evaluated. Chemicals; mepronil, toclofos-methyl and iprodione inhibited 90∼100% mycelial growth of R. solani AG1 and AG2-2 in vitro. While on the other, the chemicals inhibited only 0∼5%, 18∼46% and 30∼67% of mycelial growth of the antagonists, respectively. In field application, toclofos-methyl was the best to suppress the disease in single application, however, the combination of mepronil and T. viride 41D showed highest disease control effect among combinations of antagonists and chemicals. Effect of the combination of mepronil and T. viride 41D was similar to that of toclofos-methyl and T. viride 41D stage of disease development, but became higher in six week late. Results indicated that the combined application of selected antagonistic agent and chemical increased control efficasy of turgrass large patch.

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Removal of a synthetic broad-spectrum antimicrobial agent, triclosan, in wastewater treatment systems: A short review

  • Lee, Do Gyun
    • Environmental Engineering Research
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    • v.20 no.2
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    • pp.111-120
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    • 2015
  • Contaminants of emerging concern (CECs) including endocrine disrupting compounds (EDCs) and pharmaceuticals and personal care product chemicals (PPCPs) have recently received more attention because of their occurrence in water bodies and harmful impacts on human health and aquatic organisms. Triclosan is widely used as a synthetic broad-spectrum antimicrobial agent due to its antimicrobial efficacy. However, triclosan detected in aquatic environment has been recently considered as one of CECs, because of the potential for endocrine disruption, the formation of toxic by-products and the development of cross-resistance to antibiotics in aquatic environment. This comprehensive review focuses on the regulations, toxicology, fate and transport, occurrence and removal efficiency of triclosan. Overall, this review aims to provide better understanding of triclosan and insight into application of biological treatment process as an efficient method for triclosan removal.

Synthesis and Characterization of Water Soluble Fluorescent Copper Nanoparticles

  • Yu, Ji Soo;Kim, Sung Hun;Man, Minh Tan;Lee, Hong Seok
    • Applied Science and Convergence Technology
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    • v.27 no.4
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    • pp.75-77
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    • 2018
  • The electrostatic interaction between emerging quantum-confined nanostructures with plasmonic structures is crucial for future biological applications. Water-soluble green fluorescent copper nanoparticles (Cu-NPs) were fabricated. We demonstrate that L-ascorbic acid is considered as a key to precisely control small Cu-NPs and the capability of the surface ligands, while cetyltrimethylammonium bromide is used as a stabilizing agent controls the particle growth, and stabilizes the nanoparticles. Water-soluble green fluorescent Cu-NPs are tunable through modification of the reaction periods.

Diagnostic Significance of pH-Responsive Gd3+-Based T1 MR Contrast Agents

  • Bhuniya, Sankarprasad;Hong, Kwan Soo
    • Investigative Magnetic Resonance Imaging
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    • v.23 no.1
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    • pp.17-25
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    • 2019
  • We discuss recent advances in Gd-based $T_1$-weighted MR contrast agents for the mapping of cellular pH. The pH plays a critical role in various biological processes. During the past two decades, several MR contrast agents of strategic importance for pH-mapping have been developed. Some of these agents shed light on the pH fluctuation in the tumor microenvironment. A pH-responsive self-assembled contrast agent facilitates the visualization of tumor size as small as $3mm^3$. Optimization of various parameters is crucial for the development of pH-responsive contrast agents. In due course, the new contrast agents may provide significant insight into pH fluctuations in the human body.

Exposure Assessment for Airborne Biological Agents in Sawmills (제재업의 생물학적인자 노출실태 평가)

  • Park, Hae-Dong;Park, Hyun-Hee;Lee, In-Seop
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.20 no.4
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    • pp.274-281
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    • 2010
  • The objectives of this study are (a) to investigate the distribution patterns and exposure concentrations of biological agents in sawmill industries and (b) to compare sampling methods of biological agents. The representative processes of 5 sawmills were selected to measure total airborne bacteria, fungi, endotoxin as well as dust. Airborne bacteria and fungi were measured with one stage impactor, six stage impactor and gelatin filteration methods. Endotoxin was collected with polycarbonate filters and analysed by kinetic chromogenic Limulus Amebocyte Lysate method. Geometric mean levels of airborne bacteria, fungi, endotoxin and dust were 1,864 CFU/$m^3$, 2,252 CFU/$m^3$, 31.5 EU/$m^3$ and 2.4 mg/$m^3$. The ratios of indoor/outdoor concentrations were 3.7 for bacteria, 4.1 for fungi, 3.3 for endotoxin and 9.7 for dust. The respiratory fractions of bacteria were 68.0, 50.9, 49.2 and 45.1% in band-saw, table-saw, rip-saw process and outdoor air. The respiratory fractions of fungi were 78.7, 90.8, 87.5 and 84.8% in band-saw, table-saw, rip-saw process and outdoor air, respectively. There was no significant differences in bacterial concentrations among single stage, six stage impaction and filteration methods. But, fungal concentrations measured with filtration methods were significantly higher than those with impaction methods. Geometric mean levels of airborne bacteria and fungi were higher than the OSHA guideline values of 1,000 CFU/$m^3$. The respiratory fractions of fungi were above 75%. The concentrations of biological agents were significantly different among culture-based sampling methods. In the exposure assessments of biological agents, further studies are needed for the comparisons of diverse sampling methods and the investigations of environmental factors.