• Title/Summary/Keyword: biological applications

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A study of Brachytherapy for Intraocular Tumor (안구내 악성종양에 대한 저준위 방사선요법에 관한 연구)

  • Ji, Gwang-Su;Yu, Dae-Heon;Lee, Seong-Gu;Kim, Jae-Hyu;Ji, Yeong-Hun
    • The Journal of Korean Society for Radiation Therapy
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    • v.8 no.1
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    • pp.19-27
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    • 1996
  • I. Project Title A Study of Brachytherapy for intraocular tumor II. Objective and Importance of the project The eye enucleation or external-beam radiation therapy that has been commonly used for the treatment of intraocular tumor have demerits of visual loss and in deficiency of effective tumor dose. Recently, brachytherapy using the plaques containing radioisotope-now treatment method that decrease the demerits of the above mentioned treatment methods and increase the treatment effect-is introduced and performed in the countries, Our purpose of this research is to design suitable shape of plaque for the ophthalmic brachytherapy, and to measure absorbed doses of Ir-192 ophthalmic plaque and thereby calculate the exact radiation dose of tumor and it's adjacent normal tissue. III. Scope and Contents of the project In order to brachytherapy for intraocular tumor, 1. to determine the eye model and selected suitable radioisotope 2. to design the suitable shape of plaque 3. to measure transmission factor and dose distribution for custom made plaques 4. to compare with the these data and results of computer dose calculation models IV. Results and Proposal for Applications The result were as followed. 1. Eye model was determined as a 25mm diameter sphere, Ir-192 was considered the most appropriate as radioisotope for brachytherapy, because of the size, half, energy and availability. 2. Considering the biological response with human tissue and protection of exposed dose, we made the plaques with gold, of which size were 15mm, 17mm and 20mm in diameter, and 1.5mm in thickness. 3. Transmission factor of plaques are all 0.71 with TLD and film dosimetry at the surface of plaques and 0.45, 0.49 at 1.5mm distance of surface, respectively. 4. As compared the measured data for the plaque with Ir-192 seeds to results of computer dose calculation model by Gary Luxton et al. and CAP-PLAN (Radiation Treatment Planning System), absorbed doses are within ${\pm}10\%$ and distance deviations are within 0.4mm Maximum error is $-11.3\%$ and 0.8mm, respectively. As a result of it, we can treat the intraocular tumor more effectively by using custom made gold plaque and Ir-192 seeds.

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Feasibility Studies on the Biological Control by Augmentation and Conservation of Natural Enemies of Rice Paddy (수도해충(水稻害蟲) 천적(天敵)의 보호(保護) 및 이용(利用)에 관(關)한 기초(基礎) 연구(硏究))

  • Chang, Young Duck
    • Korean Journal of Agricultural Science
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    • v.8 no.1
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    • pp.18-28
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    • 1981
  • The purpose of this study was to establish the intergrated control of rice insect pests. Specific objectives were to reveal the diversity of natural enemies in rice field environment, to obtain basic informations of their population dynamics, and to screen the selective insecticides for the conservation of natural enemies. The results of the study were as follows. 1. In numbers of species and in numbers of each species of parasitic Hymenoptera of rice insect pests were more diverse and abundant in rice paddy leeves and banks than paddy fields. Braconid Mymarid and pteromalid were predominated in the field and their population was high during early August to mid September. 2. Of the predatory spiders, Pirata subpiraticus was the largest in number and amounted to 72% of the total, Gnatonarium dentatum, Pachygnatha clerki and Clubiona japonicola were the next. It was also found that P. subpiraticus had three generations in a year. 3. Hence the activities of the predatory spider species and parasitic Hymenoptera were high in early to mid August and September, it would be better promising to avoid chemical applications at this time of periods as possible. 4. The relative toxicity of several insecticides which have been used for the control of brown plant hopper (BPH) showed that P. subpiraticus was 1.1-73.1 times higher than BPH and G. dentatum to P. subpiraticus was 1.1-73.1 times, respectively. 5. Three conventional insecticides, Padan, Diazinon and Carbofuran were screened for toxicity to predatory spider species. The insecticides deffered in their toxicity to the predators. However, Padan was appeared to be the least toxic to the predators.

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Component Analysis and Antioxidant Activity of Oenanthe javanica Extracts (돌미나리 추출물의 함유성분 분석과 항산화 활성)

  • Hwang, Seok-Jun;Park, Sung-Jin;Kim, Jong-Dai
    • Korean Journal of Food Science and Technology
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    • v.45 no.2
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    • pp.227-234
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    • 2013
  • The purpose of this study was to determine the possibility of using Oenanthe javanica as a natural health food source. To accomplish this, its general and biological activities were measured. Its carbohydrate, crude protein, crude lipid, and ash contents were 44.7, 9.8, 8.9, and 27.8%, respectively. The K content was largest for minerals followed by Ca, P, and Mg, which means that Oenanthe javanica is an alkali material. The concentrations of total phenol and flavonoids of OJE were $88.9{\pm}0.46$ mg GAE/g, and $28.6{\pm}0.64$ mg QE/g, respectively. Gallic acid, catechin, chlorogenic acid, and caffeic acid in OJE as measured by using HPLC were $0.9{\pm}0.23$, $1.2{\pm}0.19$, $227.1{\pm}0.62$, and $4.0{\pm}0.35$ mg/g. The DPPH and ABTS radical scavenging activities of OJE were 72.2%, and 66.1%, respectively, at $1,000{\mu}g/mL$. The FRAP and reducing power of OJE were 0.79, and 0.41 absorbance units value respectively, at $1,000{\mu}g/mL$. OJE possessed significant antioxidant properties, which suggests its great potential as a functional ingredient for food applications.

Controlling of Molecular Weight and Degree of Deacetylation of Chitosan and Its Characteristics in Film Formation (키토산 분자량과 탈아세틸화도 조절 및 이에 따른 필름 특성)

  • Hwang, Kwon-T.;Park, Hyun-J.;Jung, Soon-T.;Ham, Kyung-S.;Yoo, Yong-K.;Cho, Gun-S.
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.5 no.1
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    • pp.47-55
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    • 1999
  • Applications of chitosan are related to molecular weight and degree of deacetylation(DOD) of chitosan completely. The molecular weight and DOD were greatly affected by the concentration of solution time and temperature. The degree of demineralization was not significantly different at $50^{\circ}C\;and\;70^{\circ}C$ after 30 minutes. Deproteinization decreased as process time increased. The nitrogen content was reached to 6.92% after 90 minute at $80^{\circ}C$, which is similar to theoretical nitrogen content of chitin. The DOD was 82.84% after 2 hours reaction and increased as the reaction time increased in the process. Viscosity and molecular weight are increased as recycling number of concentrated NaOH solution increased. Chemical, biological and physical properties of chitosan depend on the DOD and molecular size of the molecule. Tensile strength of the films from acetic acid solutions was between $28.9{\sim}33.6$ MPa and was generally higher than that of the films from lactic acid. Elongation of the films from lactic acid was between $97.0{\sim}109.7%$ and was generally higher than that of the films from the acetic acid. Water vapor permeability of the films prepared from lcetic acid solutions was between $1.9{\sim}2.3ng{\cdot}m/m^2{\cdot}s{\cdot}Pa$ and was generally higher than that of the films from the acetic acid.

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Status of Agrometeorological Information and Dissemination Networks (농업기상 정보 및 배분 네트워크 현황)

  • Jagtap, Shrikant;Li, Chunqiang
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.6 no.2
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    • pp.71-84
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    • 2004
  • There is a growing demand for agrometeorological information that end-users can use and not just interesting information. lo achieve this, each region/community needs to develop and provide localized climate and weather information for growers. Additionally, provide tools to help local users interpret climate forecasts issued by the National Weather Service in the country. Real time information should be provided for farmers, including some basic data. An ideal agrometeorological information system includes several components: an efficient data measuring and collection system; a modern telecommunication system; a standard data management processing and analysis system; and an advanced technological information dissemination system. While it is conventional wisdom that, Internet is and will play a major role in the delivery and dissemination of agrometeorological information, there are large gaps between the "information rich" and the "information poor" countries. Rural communities represent the "last mile of connectivity". For some time to come, TV broadcast, radio, phone, newspaper and fax will be used in many countries for communication. The differences in achieving this among countries arise from the human and financial resources available to implement this information and the methods of information dissemination. These differences must be considered in designing any information dissemination system. Experience shows that easy across to information more tailored to user needs would substantially increase use of climate information. Opportunities remain unexplored for applications of geographical information systems and remote sensing in agro meteorology.e sensing in agro meteorology.

Mechanisms for Anti-wrinkle Activities from Fractions of Black Chokeberries (블랙초크베리 분획물로부터의 주름억제 효과에 대한 작용기전)

  • Choi, Eun-Young;Kim, Eun-Hee;Lee, Jae-Bong;Do, Eun-Ju;Kim, Sang-Jin;Kim, Se-Hyeon;Park, Jeong-Yeol;Lee, Jin-Tae
    • Journal of Life Science
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    • v.26 no.1
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    • pp.34-41
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    • 2016
  • Black chokeberries (scientific name Aronia melanocarpa) have been reported to have major effects due to anti-oxidant, anti-inflammatory, and anti-cancer capabilities. In this study, we investigated the anti- wrinkle effects of A. melanocarpa, including collagenase inhibition effects and their molecular biological mechanisms, such as oxidative stress-induced matrix metalloproteinase (MMP), mitogen-activated protein (MAP) kinase, and activator protein (AP)-1 expression and/or phosphorylation. In collagenase inhibition activity, the ethyl acetate fraction of black chokeberry (AE) was 77.2% at a concentration of 500 μg/ml, which was a significant result compared to that of Epigallocatechin gallate (positive control, 83.9% in 500 μg/ml). In the reactive oxygen species (ROS) assay, the AE produced 78% of ROS in 10 μg/ml and 70% of ROS in 75 μg/ml, which was a much lower percentage than the ROS production of H2O2-induced CCRF S-180II cells. In the MTT assay, cell viability was increased dose-dependently with AE in H2O2-induced cells. In protein expression by western blot assay, the AE suppressed the expression and phosphorylation of MMPs (MMP-1, -3, -9), MAPK (ERK, JNK, and p38), and AP-1 (c-Fos and c-Jun), and expressed the pro-collagen type I in H2O2-induced cells. These results suggest that black chokeberries have anti-wrinkle and collagen-production effects, and they may be used in applications for material development in the functional food and cosmetic industries.

Potentials of Synbiotics for Pediatric Nutrition and Baby Food Applications: A Review (소아 영양 및 유아식 응용을 위한 신바이오틱스의 잠재력: 총설)

  • Jung, Hoo Kil;Kim, Sun Jin;Seok, Min Jeong;Cha, Hyun Ah;Yoon, Seul Ki;Lee, Nah Hyun;Kang, Kyung Jin
    • Journal of Dairy Science and Biotechnology
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    • v.33 no.2
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    • pp.111-118
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    • 2015
  • Probiotic, prebiotic, and synbiotic substances as well as microorganisms were added to infant formula in an attempt to influence the intestinal microflora with an aim to stimulate the growth of lactic acid bacteria, especially bifidobacteria and lactobacilli. Over the last 10 years, new synbiotic infant formulas containing probiotics and prebiotics have been proposed in order to simulate the effect of breast-feeding on the intestinal microflora. Owing to their synergistic effect, the new synbiotics are expected to be more helpful than using probiotics and prebiotics individually. Maintenance of the viability of the probiotics during food processing and the passage through the gastrointestinal tract should be the most important consideration, since a sufficient number of bacteria ($10^8cfu/g$) should reach the intended location to have a positive effect on the host. Storage conditions and the processing technology used for the manufacture of products such as infant formula adversely affect the viability of the probiotics. When an appropriate and cost-effective microencapsulation methodology using the generally recognized as safe (GRAS) status and substances with high biological value are developed, the quality of infant formulas would improve. The effect of probiotics may be called a double-effect, where one is an immunomodulatory effect, induced by live probiotics that advantageously alter the gastrointestinal microflora, and the other comprises anti-inflammatory responses elicited by dead cells. At present, a new terminology is required to define the dead microorganisms or crude microbial fractions that positively affect health. The term "paraprobiotics" (or ghost probiotics) has been proposed to define dead microbial cells (not damaged or broken) or crude cell extracts (i.e., cell extracts with complex chemical composition) that are beneficial to humans and animals when a sufficient amount is orally or topically administered. The fecal microflora of bottle-fed infants is altered when the milk-based infant formula is supplemented with probiotics or prebiotics. Thus, by increasing the proportion of beneficial bacteria such as bifidobacteria and lactobacilli, prebiotics modify the fecal microbial composition and accordingly regulate the activity of the immune system. Therefore, considerable attention has been focused on the improvement of infant formula quality such that its beneficial effects are comparable to those of human milk, using prebiotics such as inulin and oligosaccharides and potential specific probiotics such as bifidobacteria, which selectively stimulate the proliferation of beneficial bacteria in the microflora and the indigenous intestinal metabolic activity of the microflora.

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Attenuation of Lipopolysaccharide-induced Inflammatory and Oxidative Response by 5-Aminolevulinic Acid Phosphate in RAW 264.7 Macrophages (RAW 264.7 대식세포에서 lipopolysaccharide 자극에 의한 염증성 및 산화적 스트레스에 미치는 5-aminolevulinic acid phosphate의 영향)

  • Ji, Seon Yeong;Kim, Min Yeong;Hwangbo, Hyun;Lee, Hyesook;Hong, Su Hyun;Cha, Hee-Jae;Kim, Heui-Soo;Kim, Suhkmann;Choi, Yung Hyun
    • Journal of Life Science
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    • v.31 no.9
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    • pp.818-826
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    • 2021
  • 5-Aminolevulinic acid phosphate (5-ALA-p) is a substance obtained by eluting 5-ALA (a natural delta amino acid) with aqueous ammonia, adding phosphoric acid to the eluate, and then adding acetone to confer properties suitable for use in photodynamic therapy applications. However, its pharmacological efficacy, including potential mechanisms of antioxidant and anti-inflammatory reactions, remains unclear. This study aimed to investigate the effects of 5-ALA-p on oxidative and inflammatory stresses in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Our data showed that 5-ALA-p significantly inhibited excessive phagocytic activity via LPS and attenuated oxidative stress in LPS-treated RAW 264.7 cells. Furthermore, 5-ALA-p improved mitochondrial biogenesis reduced by LPS, suggesting that 5-ALA-p restores mitochondrial damage caused by LPS. Additionally, 5-ALA-p significantly suppressed the release of nitric oxide (NO) and pro-inflammatory cytokines, such as tumor necrosis factor α (TNF-α), interleukin (IL)-1β, and IL-6, which are associated with the inhibition of inducible NO synthase and respective cytokine expression. Furthermore, 5-ALA-p reduced the nuclear translocation of nuclear factor-kappa B (NF-κB) and inhibited phosphorylation of mitogen-activated protein kinases (MAPKs), indicating that the anti-inflammatory effect of 5-ALA-p is mediated through the suppression of NF-κB and MAPK signaling pathways. Based on these results, 5-ALA-p may serve as a potential candidate to reduce inflammation and oxidative stress.

Absorption Characteristics of Water-Lean Solvent Composed of 3-(Methylamino)propylamine and N-Methyl-2-Pyrrolidone for CO2 Capture (3-메틸아미노프로필아민과 N-메틸-2-피롤리돈을 포함한 저수계 흡수제의 CO2 포집 특성)

  • Shuai Wang;Jeong Hyeon Hong;Jong Kyun You;Yeon Ki Hong
    • Korean Chemical Engineering Research
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    • v.61 no.4
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    • pp.555-560
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    • 2023
  • Conventional aqueous amine-based CO2 capture has a problem in that a large amount of renewable energy is required for CO2 stripping and solvent regeneration in its industrial applications. This work proposes a water-lean absorbent that can reduce regeneration energy by lowering the water content in the absorbent with high absorption capacity for CO2. To this purpose, this water-lean solvent introduced NMP (N-methyl-2-pyrrolidone), which has a higher physical solubility in CO2 and a low specific heat capacity comparing to water, along with 3-methylaminopropylamine (MAPA), a diamine, into the absorbent. The circulating absorption capacity and absorption rate for CO2 of this water-lean solvent were measured using a packed tower. When NMP was added to the absorbent, the absorption rate was improved. In the case of the absorbent containing 2.5M MAPA was used, the maximum circulating absorption capacity was obtained when 10 wt% of NMP was included in absorbent. The overall mass transfer coefficient increased as the concentration of NMP increased. However, at loading values higher than 0.5, the increment in mass transfer coefficient decreased as the concentration of NMP increased. When the lean loading value is low, the mass transfer resistance due to viscosity of the absorbent is low, so the overall mass transfer coefficient increases with the addition of NMP. However, as the lean loading value increases, the viscosity of the absorbent increases, and the diffusivity of CO2 and MAPA decreases, resulting in sharply decreasing of the overall mass transfer coefficient.

Current and Future Perspectives of Lung Organoid and Lung-on-chip in Biomedical and Pharmaceutical Applications

  • Junhyoung Lee;Jimin Park;Sanghun Kim;Esther Han;Sungho Maeng;Jiyou Han
    • Journal of Life Science
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    • v.34 no.5
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    • pp.339-355
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    • 2024
  • The pulmonary system is a highly complex system that can only be understood by integrating its functional and structural aspects. Hence, in vivo animal models are generally used for pathological studies of pulmonary diseases and the evaluation of inhalation toxicity. However, to reduce the number of animals used in experimentation and with the consideration of animal welfare, alternative methods have been extensively developed. Notably, the Organization for Economic Co-operation and Development (OECD) and the United States Environmental Protection Agency (USEPA) have agreed to prohibit animal testing after 2030. Therefore, the latest advances in biotechnology are revolutionizing the approach to developing in vitro inhalation models. For example, lung organ-on-a-chip (OoC) and organoid models have been intensively studied alongside advancements in three-dimensional (3D) bioprinting and microfluidic systems. These modeling systems can more precisely imitate the complex biological environment compared to traditional in vivo animal experiments. This review paper addresses multiple aspects of the recent in vitro modeling systems of lung OoC and organoids. It includes discussions on the use of endothelial cells, epithelial cells, and fibroblasts composed of lung alveoli generated from pluripotent stem cells or cancer cells. Moreover, it covers lung air-liquid interface (ALI) systems, transwell membrane materials, and in silico models using artificial intelligence (AI) for the establishment and evaluation of in vitro pulmonary systems.