• Title/Summary/Keyword: Dilution Factor

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Parabiosis and Blood Exchange Techniques in Aging Research (개체병렬결합(parabiosis)실험모델과 혈액교환을 이용한 노화(aging)연구 분석)

  • Kyung Tae Chung
    • Journal of Life Science
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    • v.33 no.2
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    • pp.208-215
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    • 2023
  • In recent decades, the field of aging research has progressed from the genetic and cellular levels to in vivo models of blood exchange. Since genes capable of extending the lifespan in C. elegance have been reported, various potential target molecules have been discovered through genomics, proteomics, metabolomics, and transcriptomics. Accordingly, research on the interactions between target molecules has also been increasing. The parabiosis method, in which two experimental animals are surgically combined, was introduced, and a factor that could reverse the aging phenomenon was discovered using this method. The parabiosis method is used to find more accurate and effective aging-reversal factors that could exist in young blood. As more new evidence has been revealed, the parabiosis method has established a new paradigm for aging research. Moreover, a device capable of exchanging blood elaborately in laboratory animals was published in 2022 and presented new results necessary for aging reversal. Since GDF11, was reported, many other anti-aging candidates that are soluble factors in blood, such as β2m, TIMP2, VCAM1, Gpld1, and clusterin, have been discovered. In addition, mcicroglia cells and neuroinflammation have been directly proven to be aging factors. These latest research results were obtained by parabiosis, the newly designed device for plasmapheresis, and injecting young blood or conditioned blood methods. In this review, we discuss the latest research results using the device and young blood administration in old mice.

Pytotoxicity by Continuous Spraying of Fruit Fire Blight Disinfectant During Growing Season of Apple and Pear (과수 화상병 방제약제의 사과·배 생육기 연용 살포에 의한 약해)

  • Se Hee Kim;Song-Hee Ryu;Byeonghyeon Yun;Kang Hee Cho;Sang-Yun Cho;Jung Gwan Park
    • Korean Journal of Plant Resources
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    • v.36 no.1
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    • pp.100-106
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    • 2023
  • In order to control the fire blight disease, all plants within the radius of the diseased orchard were removed in the early stage of the outbreak, or antibiotics control was performed for prevention. Since the beginning of antibiotics use on plants, the potential for development of resistance to antibiotics by the plant pathogen and unintended detrimental effects on the fruit trees and environment has become a problem. The purpose of this study is to determine the degree of phytotoxicity to fruit trees caused by excessive spraying of the fire blight disease disinfectant and to establish basic data for safe disinfectant guide. We analyzed whether damage to the fruit tree and the maximum residual limit of fruit was exceeded when three kinds of the fire blight disease disinfectants were continuously sprayed in excess of the number of safe use during the growing season. There was no phytotoxicity in apple 'Fuji' and pear 'Niitaka', and oxolinic acid was detected beyond the limit of quantitation in 'Fuji' grown without a bag, and the other disinfectants were detected below the maximum residue limit. When these disinfectants are continuously sprayed in excess of the number of safe, phytotoxicity may remain on the fruit. Therefore, it is necessary to observe the prescribed dilution factor and observe the safe frequency and the timing of use.

Change in the Sensitivity to Propiconazole of Fusarium graminearum Species Complex Causing Head Blight of Barley and Wheat in Jeolla Province (전남북 지역 맥류 붉은곰팡이병균의 Propiconazole 약제에 대한 감수성 변화)

  • Jiseon Baek;Ju-Young Nah;Mi-Jeong Lee;Su-Bin Lim;Jung-Hye Choi;Ja Yeong Jang;Theresa Lee;Hyo-Won Choi;Jeomsoon Kim
    • The Korean Journal of Mycology
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    • v.50 no.4
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    • pp.281-289
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    • 2022
  • Fusarium head blight is an important disease of small grains. It is mainly caused by members of the Fusarium graminearum species complex (FGSC). Barley and wheat growers spray fungicides, especially demethylation-inhibitor fungicides, to suppress the disease. The objective of this study was to examine the changes in the sensitivity of the FGSC population to the triazole fungicide, propiconazole. A total of 124 and 350 isolates of FGSC were obtained from barley and wheat in Jeolla Province during 2010-2016 and 2020-2021, respectively. The species identity and trichothecene chemotypes of the FGSC isolates were determined based on polymerase chain reaction assays targeting translation elongation factor 1-alpha and TRI12 genes, respectively. Sensitivity to propiconazole was determined based on the effective concentration that reduced 50% of the mycelial growth (EC50) using the agar dilution method. Of all isolates, F. asiaticum with the nivalenol chemotype was the most common (83.9% in 2010-2016 and 96.0% in 2020-2021), followed by F. asiaticum with the 3-acetyl deoxynivalenol chemotype (12.1% in 2010-2016 and 2.9% in 2020-2021). The EC50 values of the isolates collected in 2010-2016 and 2020-2021 ranged from 0.0180 to 11.0166 ㎍/mL and 1.3104 to 17.9587 ㎍/mL, respectively. The mean EC50 value of the isolates increased from 3.8648 ㎍/mL in 2010-2016 to 5.9635 ㎍/mL in 2020-2021. The baseline resistance to propiconazole was determined to be 7 ㎍/mL, based on the EC50 value of isolates collected in 2010-2016, and the ratio of resistant isolates increased from 9.7% in 2010-2016 to 28.6% in 2020-2021.

The Ability of Anti-tumor Necrosis Factor Alpha(TNF-${\alpha}$) Antibodies Produced in Sheep Colostrums

  • Yun, Sung-Seob
    • 한국유가공학회:학술대회논문집
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    • 2007.09a
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    • pp.49-58
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    • 2007
  • Inflammatory process leads to the well-known mucosal damage and therefore a further disturbance of the epithelial barrier function, resulting abnormal intestinal wall function, even further accelerating the inflammatory process[1]. Despite of the records, etiology and pathogenesis of IBD remain rather unclear. There are many studies over the past couple of years have led to great advanced in understanding the inflammatory bowel disease(IBD) and their underlying pathophysiologic mechanisms. From the current understanding, it is likely that chronic inflammation in IBD is due to aggressive cellular immune responses including increased serum concentrations of different cytokines. Therefore, targeted molecules can be specifically eliminated in their expression directly on the transcriptional level. Interesting therapeutic trials are expected against adhesion molecules and pro-inflammatory cytokines such as TNF-${\alpha}$. The future development of immune therapies in IBD therefore holds great promises for better treatment modalities of IBD but will also open important new insights into a further understanding of inflammation pathophysiology. Treatment of cytokine inhibitors such as Immunex(Enbrel) and J&J/Centocor(Remicade) which are mouse-derived monoclonal antibodies have been shown in several studies to modulate the symptoms of patients, however, theses TNF inhibitors also have an adverse effect immune-related problems and also are costly and must be administered by injection. Because of the eventual development of unwanted side effects, these two products are used in only a select patient population. The present study was performed to elucidate the ability of TNF-${\alpha}$ antibodies produced in sheep colostrums to neutralize TNF-${\alpha}$ action in a cell-based bioassay and in a small animal model of intestinal inflammation. In vitro study, inhibitory effect of anti-TNF-${\alpha}$ antibody from the sheep was determined by cell bioassay. The antibody from the sheep at 1 in 10,000 dilution was able to completely inhibit TNF-${\alpha}$ activity in the cell bioassay. The antibodies from the same sheep, but different milkings, exhibited some variability in inhibition of TNF-${\alpha}$ activity, but were all greater than the control sample. In vivo study, the degree of inflammation was severe to experiment, despite of the initial pilot trial, main trial 1 was unable to figure out of any effect of antibody to reduce the impact of PAF and LPS. Main rat trial 2 resulted no significant symptoms like characteristic acute diarrhea and weight loss of colitis. This study suggested that colostrums from sheep immunized against TNF-${\alpha}$ significantly inhibited TNF-${\alpha}$ bioactivity in the cell based assay. And the higher than anticipated variability in the two animal models precluded assessment of the ability of antibody to prevent TNF-${\alpha}$ induced intestinal damage in the intact animal. Further study will require to find out an alternative animal model, which is more acceptable to test anti-TNF-${\alpha}$ IgA therapy for reducing the impact of inflammation on gut dysfunction. And subsequent pre-clinical and clinical testing also need generation of more antibody as current supplies are low.

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Identification, Mycological Characteristics and Response to fungicides of Anthracnose Pathogen Isolated from Pepper and Boxthorn in Cheongyang (청양 지역 고추와 구기자에서 분리한 탄저병균의 동정, 균학적 특징 및 살균제 저항성)

  • Kim, Gahye;Kim, Joohyeng;Kim, Heung Tae
    • The Korean Journal of Pesticide Science
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    • v.19 no.3
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    • pp.335-344
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    • 2015
  • It was conducted to identify all 47 isolates obtained from infected fruits of pepper and boxthorn, and to investigate the mycological characteristics and the response to fungicides. All of 11 isolates from pepper were identified as Colletotrichum acutatum included into A2 group. Among 36 isolates from boxthorn, 14 isolates were identified as C. gloeosporioides, and the others were done as C. acutatum, which were composed as A1 group with 15 isolates and A3 with 7 isolates. After incubating the isolates on PDA at $25^{\circ}C$ for 10 days, the colony color of C. acutatum was greyish white, while that of C. gloeosporioides was orange at center of colony and was gradually turned into an greyish white to the periphery. The rate of conidia showing ellongated ellipsoidal shape with round ends was over 95% in C. acutatum isolated from pepper. However, C. acutatum isolated from boxthorn produced ellongated ellipsoidal conidia with the rate of 75%, and the others were pointed at one or both ends. Regardless of species of Colletotrichum, all isolated used in this study was showed an optimal temperature at $25^{\circ}C$. $EC_{50}$ values of all isolates of Colletotrichum spp. to 2 fungicides as carbendazim and the mixture of carbendazim and diethofencarb was investigated by an agar dilution method. With C. acutatum isolates from pepper belonged to A2 group, the mean of $EC_{50}$ value to carbendazim and the mixture of carbendazim and diethofencarb was 0.68 and $3.16{\mu}g/ml$, respectively. In the case of C. acutatum isolates from boxthorn, which were divided into 2 groups as A1 and A3 group, that to carbendazim was 0.21 at A1 and $0.24{\mu}g/ml$ at A3, while that to the mixture was 1.52 and $3.35{\mu}g/ml$. Isolates of C. gloeosporioides showed the mean of $EC_{50}$ value was $0.12{\mu}g/ml$ to carbendazim and $0.92{\mu}g/ml$ to the mixture. The value of resistant factor was higher in the isolates of C. acutatum obtained in boxthorn than those from pepper.

Determination of methamphetamine, 4-hydroxymethamphetamine, amphetamine and 4-hydroxyamphetamine in urine using dilute-and-shoot liquid chromatography-tandem mass spectrometry (시료 희석 주입 LC-MS/MS를 이용한 소변 중 메스암페타민, 4-하이드록시메스암페타민, 암페타민 및 4-하이드록시암페타민 동시 분석)

  • Heo, Bo-Reum;Kwon, NamHee;Kim, Jin Young
    • Analytical Science and Technology
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    • v.31 no.4
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    • pp.161-170
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    • 2018
  • The epidemic of disorders associated with synthetic stimulants, such as methamphetamine (MA) and amphetamine (AP), is a health, social, legal, and financial problem. Owing to the high potential of their abuse and addiction, reliable analytical methods are required to detect and identify MA, AP, and their metabolites in biological samples. Thus, a dilute-and-shoot liquid chromatography-tandem mass spectrophotometry (LC-MS/MS) was developed for simultaneous determination of MA, 4-hydroxymethamphetamine (4HMA), AP, and 4-hydroxyamphetamine (4HA) in urine. Urine sample ($100{\mu}L$) was mixed with $50{\mu}L$ of mobile phase consisting of 0.4 % formic acid and methanol and $50{\mu}L$ of working internal-standard solution. Aliquots of $8{\mu}L$ diluted urine was injected into the LC-MS/MS system. For all analytes, chromatographic separation was performed using a C18 reversed-phase column with gradient elution and a total run time of 5 min. The identification and quantification were performed by multiple reaction monitoring (MRM). Linear least-squares regression was conducted to generate a calibration curve, with $1/x^2$ as the weighting factor. The linear ranges were 2.0-200, 1.0-800, and 10-2500 ng/mL for 4HA and 4HMA, AP, and MA, respectively. The inter- and intraday precisions were within 6.6 %, whereas the inter- and intraday accuracies ranged from -14.9 to 11.3 %. The low limits of quantification were 2.0 ng/mL (4HA and 4HMA), 1.0 ng/mL (AP), and 10 ng/mL (MA). The proposed method exhibited satisfactory selectivity, dilution integrity, matrix effect, and stability, which are required for validation. Moreover, the purification efficiency of high-speed centrifugation was clearly higher than 6-15 % for QC samples (n=5), which was higher than that of the membrane-filtration method. The applicability of the proposed method was tested by forensic analysis of urine samples from drug abusers.

Qualities and Anti-inflammatory Activity of Kyungokgos Sold in Local Markets (국내 시판 경옥고 제품의 품질 특성 및 항염증 활성)

  • Lee, Ka-Soon;Kim, Gwan-Hou;Kim, Hyun-Ho;Seong, Bong-Jae;Kim, Sun-Ick;Han, Seung-Ho;Kang, Eun Ju;Yoo, Yung Choon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.3
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    • pp.335-341
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    • 2013
  • Kyungokgos purchased in local markets in Korea vary in their combination and mixing ratios during processing. This study was investigated qualities of Kyungokgos manufactured traditionally to evaluating its qualities. The general components of Kyungokgos were moisture (18.62~49.78%), ash (0.198~1.211%), protein (0.89~3.58%), lipid (0.16~1.14%) and carbohydrates (47.95~77.08%). The color values of L, a, and b were 26.49~73.87, 16.51~38.64, and 45.41~88.94, respectively. The viscosity was classified into three non-Newtonian type groups: high, medium, and non-dilatant, according to the increase of loop execution times. Three extracts (KOG-1, -7, and -8, in a 30-fold dilution) showed no cytotoxicity toward RAW 264.7 cells, while the extracts of KOG-2, -4, and -5 showed a low cytotoxic effect. KOG-1 and -2 extracts with low cytotoxicity markedly inhibited the production of the inflammatory mediators-nitric oxide (NO) and tumor necrosis factor-alpha (TNF-${\alpha}$) in LPS-stimulated RAW 264.7 cells. These results indicate that KOG-1 and -2 extracts have anti-inflammatory activity in LPS-stimulated RAW 264.7 macrophages.

Production of Concentrated Blueberry Vinegar Using Blueberry Juice and Its Antioxidant and Antimicrobial Activities (블루베리 농축식초 제조 및 이들의 항산화 및 항균 활성)

  • Oh, Hyeonhwa;Jang, Sowon;Jun, Hyun-Il;Jeong, Do-Youn;Kim, Young-Soo;Song, Geun-Seoup
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.6
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    • pp.695-702
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    • 2017
  • This study was carried out to investigate the effects of seed vinegar on antioxidant activity and antimicrobial activities of concentrated blueberry vinegar (CBV). Of the nine strains of yeast and six strains of acetic acid bacteria provided by the Microbial Institute for Fermentation Industry, each strain of yeast (Saccharomyces cerevisiae SRCM 100610, showing the highest ethanol content) and acetic acid bacteria (Acetobacter pasteurianus SRCM 101342, showing the highest total acidity) was selected for production of CBVs. Sugar content, pH, total acidity, total phenolic content (TPC), and browning intensity (280 nm and 420 nm) in CBVs using concentrated blueberry juice were $11.05{\sim}12.70^{\circ}Brix$, 2.63~2.98, 1.65~5.72%, 3.03~4.24 mg/mL, 0.95~1.50, and 0.11~0.20, respectively. Sugar content and total acidity of CBVs increased upon addition of seed vinegar, whereas pH, TPC, and browning intensity decreased. Of all CBVs with various additions of seed vinegar, the control showed the lowest $EC_{50}$ values in DPPH radical scavenging assay, ABTS radical scavenging assay, and reducing power (23.80, 19.48, and 79.21 dilution factor, respectively), whereas the 40% seed vinegar group showed the highest clear zone diameter values for Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and Bacillus cereus (4.31, 4.59, 5.81, and 3.97, respectively). Antioxidant activities of CBVs were closely correlated with their TPC, browning intensity at 280 nm, pH, and total acidity values, showing correlation determination coefficient ($R^2$) values higher 0.82. However, antimicrobial activities of CBVs were closely correlated with their pH and total acidity values, showing higher $R^2$ values more than 0.92. These results suggest that CBVs using concentrated blueberry juice, S. cerevisiae SRCM 100610, and A. pasteurianus SRCM 101342 may be useful as potentially functional foods for enhancing health.

The Variability of CDOM Along the Salinity Gradients of the Seomjin River Estuary During Dry and Wet Seasons (우기와 건기 중 섬진강 하구역에서 염분경사에 따른 유색용존유기물의 변동성)

  • Lee, Jae Hwan;Park, Mi Ok
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.22 no.4
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    • pp.362-371
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    • 2016
  • The distribution patterns of Chromophoric Dissolved Organic Matter (CDOM) and the chemical characteristics of CDOM in the Seomjin river estuary were investigated in March, June and July 2012 in order to determine the spatial and temporal variability of CDOM along the salinity gradient considering the effects of mixing, nutrients and Chl a. The average CDOM values were $1.0{\pm}0.3m^{-1}$, $1.3{\pm}0.4m^{-1}$, and $1.4{\pm}0.3m^{-1}$ in March, June and July, respectively. A high concentration of CDOM (greater than $1.5m^{-1}$) was found at the head of the river which decreased towards the river mouth to as low as less than $0.5m^{-1}$. The average concentrations of CDOM increased from the dry season (March and June) to the wet season (July), and the average slope values ($S_{300-500}$), which were used as indicators of CDOM characteristics and sources, were in the range of $0.013-0.018m^{-1}$. The CDOM and $S_{300-50}$ values showed that not only the concentration of CDOM but also the chemical properties of DOM clearly changed between upstream and downstream in the Seomjin river. CDOM and FDOM showed a negative correlation with salinity ($R^2$ > 0.8), and CDOM was positively correlated with FDOM. Furthermore, the mixing pattern of CDOM was confirmed as conservative for all seasons. The main environmental factors influencing the concentration of CDOM was confirmed as conservative for all seasons. The main environmental factors influencing the concentration of CDOM were salinity (mixing) and water temperature, which meant the dilution of low CDOM seawater, was the controlling factor for the spatial distribution of CDOM. Increases in water temperature seemed to induce the production of CDOM during summer (June and July) through the biological degradation of DOM either by microbial activity or photo-degradation.

Dissipation Pattern of Boscalid in Cucumber under Greenhouse Condition (시설 내 오이 재배 중 살균제 Boscalid의 잔류특성)

  • Lee, Jong-Hwa;Park, Hee-Won;Keum, Young-Soo;Kwon, Chan-Hyeok;Lee, Young-Deuk;Kim, Jeong-Han
    • The Korean Journal of Pesticide Science
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    • v.12 no.1
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    • pp.67-73
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    • 2008
  • The dissipation patterns of a boscalid in cucumber under greenhouse condition was investigated to establish pre-harvest residue limit (PHRL) and biological half-life. Initial concentration of boscalid in cucumber at standard application rate was $7.29\;mg\;kg^{-1}$ and decreased to $0.04\;mg\;kg^{-1}$ after 15 days with half-life of 1.9 day, while the initial concentration was $14.69\;mg\;kg^{-1}$ and decreased to $0.11\;mg\;kg^{-1}$ after same period with half lift of 2.0 day at double application rate. PHRL was suggested by prediction curve derived from the decay curve of boscalid at double rate treatment. For example, $10.39\;mg\;kg^{-1}$ was calculated for 10 days before harvest, and $1.73\;mg\;kg^{-1}$ for 5 days. Dilution effect was major factor far the decrease of boscalid residue due to fast increasement of weight of cucumber during cultivation. Final residues level of boscalid was predicted based on the dissipation curve and guideline on safe use, when boscalid was used to control powdery mildew and gray mold. At standard rate application, $1.26\;mg\;kg^{-1}$ and $1.33\;mg\;kg^{-1}$ were calculated as final residue levels for control powdery mildew and gray mold, respectively, which are above the MRL(Meximum Residue Limit).