• Title/Summary/Keyword: Screening curve method

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Screening and Characteristics of a Mutant of Actinoplanes teichomyceticus ATCC31121 Highly Producing Teicoplanin (Teicoplanin 생산성이 우수한 Actinoplanes teichomyceticus ATCC31121 변이주 선별 및 배양학적 특성)

  • 노용택
    • Korean Journal of Microbiology
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    • v.37 no.4
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    • pp.299-304
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    • 2001
  • Teicoplanin is a kind of glycopeptide antibiotics produced by Actinoplanes teichomyceticus, and used in the clinical antibiotic such as vancomycin against methicillin-resistant Stabphylococcus aureus (MRSA). Actino planes teichomyceticus ATCC 31121 was mutated with UV to obtain a superior mutant strain with increased level of teicoplanin production. In this investigation, lethal curve was obtained and the optimal condition to induce mutagenesis was determined to isolate the desirable mutant strain. It was also confirmed that teicoplanin activities by agar diffusion method was compared with the parent strain. One mutant strain, T991014-1 with the highest productivity, was finally selected, and was characterized through the various tests such as amylase activity, protease activity, halotolerance, antibiotic resistance, autotoxicity, and productivity. Ad fermentation characteristics of the mutant strain were also studied.

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GIS AND WEB-BASED DSS FOR PRELIMINARY TMDL DEVELOPMENT

  • Choi, Jin-Yong;Bernard A. Engel;Yoon, Kwang-Sik
    • Water Engineering Research
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    • v.4 no.1
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    • pp.19-30
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    • 2003
  • TMDL development and implementation have great potential fur use in efforts to improve water quality management, but the TMDL approach still has several difficulties to overcome in terms of cost, time requirements, and suitable methodologies. A well-defined prioritization approach for identifying watersheds of concern among several tar-get locations that would benefit from TMDL development and implementation, based on a simple screening approach, could be a major step in solving some of these difficulties. Therefore, a web-based decision support system (DSS) was developed to help identify areas within watersheds that might be priority areas for TMDL development. The DSS includes a graphical user interface based on the HTML protocol, hydrological models, databases, and geographic information system (GIS) capabilities. The DSS has a hydrological model that can estimate non-point source pollution loading based on over 30 years of daily direct runoff using the curve number method and pollutant event mean concentration data. The DSS provides comprehensive output analysis tools using charts and tables, and also provides probability analysis and best management practice cost estimation. In conclusion, the DSS is a simple, affordable tool for the preliminary study of TMDL development via the Internet, and the DSS web site can also be used as an information web server for education related to TMDL.

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A Rapid, Simple Determination of Sulfur-containing Compounds and Methylmalonic Acid on Plasma using GC-MS-SIM for the Diagnosis of Homocysteinemia (혈장 중 황함유 화합물과 메틸말론산의 신속 간편한 분석법 개발; GC-MS-SIM을 이용한 호모시스테인혈증의 진단)

  • Yoon, Hye-Ran;Thapa, Maheshwor
    • Journal of The Korean Society of Inherited Metabolic disease
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    • v.15 no.3
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    • pp.138-146
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    • 2015
  • Purpose: If early diagnosis is not made, patients with metabolic disorders as homocystinemia rapidly progress to physical defect or mental retardation resulted in storage of the toxic material into the brain. Therefore, it is necessary to develop an analytical method for a rapid screening and/or correct confirmation diagnosis. Methods: The standard solution of sulfur amino acids spiked plasma was subjected to protein precipitation with methanol, and then consecutively derivatized with trimethylsilyl (TMS) and trifluoroacyl (TFA) and determined by GC-MS. The formation of TMS derivative of the hydroxyl and TFA derivative of amino functional group was performed by BSTFA and MBTFA, respectively. Selective ion monitoring (SIM) mode was used for quantification with selected specific ions. Results: A calibration curve on standard spiked pooled plasma showed a linear relationship with correlation coefficient of 0.9936-0.9992 for all compounds over the range of 0.1-300 ng. The precision and accuracy were within S.D. of 1-15% and RSD of 1-15% for intra-day assay at 2 ng/mL, 15 ng/mL and 30 ng/mL. LOD and LOQ was 0.4 ng/mL and 4 ng/mL respectively. Conclusion: A rapid analytical method was developed to quantify sulfur amino acids and methyl malonic acid, after two-step derivatization procedure with good sensitivity and specificity on human plasma. Advantages of a new method are simplicity and rapidity. The method could be useful for routine analysis, diagnosis of homocysteinemia.

In Vitro Screening of Tannic Acid-based Eco-friendly Farming Material (notice no. 2-4-064) against Plant Pathogenic Bacteria (탄닌산을 함유한 친환경농자재(공시번호 2-4-064)의 식물병원세균 기내 억제효과)

  • Han, Kyu Suk;Ju, Ho-Jong;Hong, Jin Sung;Chung, Jong-Sang;Park, Duck Hwan
    • Korean Journal of Organic Agriculture
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    • v.24 no.4
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    • pp.945-955
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    • 2016
  • To date, chemical managements of plant bacterial diseases are complicated by limitations on use of antibiotics in agriculture, antibiotic resistance development, and limited efficacy of alternative control agents. In this study, thus, we performed screening of eco-friendly farming material (notice no. 2-4-064) containing tannic acid as new antibacterial-activity against 7 plant bacterial pathogens: Pectobacterium carotovorum subsp. carotovorum (Pcc), Ralstonia solanacearum (Rs), Acidovorax avenae subsp. citrulli (Aac), Xanthomonas cirti pv. citri (Xcc), Erwinia pyrifoliae (Ep), Clavibacter michiganensis subsp. michiganensis (Cmm), and Streptomyces scabies (Sc), Initial screening of antibacterial effects of eco-friendly farming material was performed using the paper disk diffusion method and co-cultivation in broth culture. Tannic acid based eco-friendly farming material showed inhibitory effect against Pcc, Rs, Aac, Xcc, Cmm, and Ss, whereas it did not show inhibition zone against Ep. However, when it tested by co-cultivation in broth culture, it showed strong inhibition effect against all pathogens that declined growth curve compared to bacterial pathogen only. Interestingly, when we observed morphological changes on those pathogens by SEM, cell morphologies of 7 pathogens were slightly changed that seem to be malfunction in their cell envelope.

Development and Validation of a Simple Index Based on Non-Enhanced CT and Clinical Factors for Prediction of Non-Alcoholic Fatty Liver Disease

  • Yura Ahn;Sung-Cheol Yun;Seung Soo Lee;Jung Hee Son;Sora Jo;Jieun Byun;Yu Sub Sung;Ho Sung Kim;Eun Sil Yu
    • Korean Journal of Radiology
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    • v.21 no.4
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    • pp.413-421
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    • 2020
  • Objective: A widely applicable, non-invasive screening method for non-alcoholic fatty liver disease (NAFLD) is needed. We aimed to develop and validate an index combining computed tomography (CT) and routine clinical data for screening for NAFLD in a large cohort of adults with pathologically proven NAFLD. Materials and Methods: This retrospective study included 2218 living liver donors who had undergone liver biopsy and CT within a span of 3 days. Donors were randomized 2:1 into development and test cohorts. CTL-S was measured by subtracting splenic attenuation from hepatic attenuation on non-enhanced CT. Multivariable logistic regression analysis of the development cohort was utilized to develop a clinical-CT index predicting pathologically proven NAFLD. The diagnostic performance was evaluated by analyzing the areas under the receiver operating characteristic curve (AUC). The cutoffs for the clinical-CT index were determined for 90% sensitivity and 90% specificity in the development cohort, and their diagnostic performance was evaluated in the test cohort. Results: The clinical-CT index included CTL-S, body mass index, and aspartate transaminase and triglyceride concentrations. In the test cohort, the clinical-CT index (AUC, 0.81) outperformed CTL-S (0.74; p < 0.001) and clinical indices (0.73-0.75; p < 0.001) in diagnosing NAFLD. A cutoff of ≥ 46 had a sensitivity of 89% and a specificity of 41%, whereas a cutoff of ≥ 56.5 had a sensitivity of 57% and a specificity of 89%. Conclusion: The clinical-CT index is more accurate than CTL-S and clinical indices alone for the diagnosis of NAFLD and may be clinically useful in screening for NAFLD.

Detection Characteristics of Gamma-Irradiated Korean Medicinal Herbs by Using PSL, TL, and ESR (PSL, TL 및 ESR 분석에 의한 감마선 조사 한약재의 검지 특성)

  • Yang, Hee-Sun;Park, Yong-Dae;Jin, Chang-Hyun;Choi, Dae-Seong;Chung, Hyung-Wook;Byun, Myung-Woo;Jeong, Il-Yun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.11
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    • pp.1529-1533
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    • 2008
  • The detection characteristics of gamma-irradiated ($0{\sim}10.0\;kGy$) medicinal herbs (Platycodon grandiflorum, Acanthopanax chiisanensis) were investigated by photostimulated luminescence (PSL), thermoluminescence (TL), and electron spin resonance (ESR). The results of the PSL, a first screening method in comparison with the TL, showed photon counts greater than 5,000 counts/60 s (positive) in the irradiated samples, while the non-irradiated samples yielded photon counts less than 700 counts/60 s (negative). The TL was also applied for the detection method of irradiated medicinal herbs and showed that the non-irradiated sample revealed a glow curve with a low intensity, while the irradiated samples showed a higher intensity. These results were normalized by re-irradiating the mineral grains with a irradiation dose of 1.0 kGy, and a second glow curve was recorded. The ratio of the intensity of the first glow curve ($TL_1$) to that after the normalization dose ($TL_2$) was determined and compared with the recommended threshold values. TL ratio ($TL_1/TL_2$) was below 0.007 for the non-irradiated sample and higher than 0.1 for all irradiated samples (above 1.0 kGy). ESR spectroscopy revealed specific signals (6.065 mT) derived from free radicals in cellulose containing irradiated medicinal herbs. The P. grandiflorum showed clearer signals than A. chiisanensis. From the results of our studies, the PSL, TL, and ESR determinations were found to be suitable for the detection of irradiated medicinal herbs such as P. grandiflorum and A. chiisanensis.

The Relationship Between Epicardial Adipose Tissue and Diabetes Mellitus (심장외막지방두께와 당뇨와의 연관성 연구)

  • Kim, Sun-Hwa;Kim, Jung-Hoon;Im, In-Chul
    • Journal of radiological science and technology
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    • v.41 no.4
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    • pp.305-312
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    • 2018
  • The incidence of cardiovascular disease increases rapidly after 40's. The thickness of the epicardial adipose tissue was measured to analyze the risk factors affecting the thickness change. We present the cut off value for the epicardial adipose tissue thickness for high impacted variables. For the study, 547 patients underwent echocardiography, epicardial adipose tissue thickness, body mass index, abdominal subcutaneous fat thickness and diabetes mellitus were used as analytical variables. As a result, multiple regression analysis of age group showed that diabetes mellitus was highly influential in all age group, so we could predict the cut off value for the epicardial adipose tissue thickness for diabetes mellitus. As a result of ROC curve analysis, cut off value of 7.44 mm was obtained with sensitivity of 79.6% and specificity of 60.6% for diab etes variab le. Logistic regression analysis b ased on this value showed that the risk for diab etes increased 6 times with each increase in the thickness of the epicardial adipose tissue. Among the various obesity indexes, epicardial adipose tissue is used as an important index especially to prevent the risk of cardiovascular disease. Therefore, we suggest that the use of echocardiography as a routine screening method for the prevention of cardiovascular disease and metabolic syndrome, which is rapidly increasing in patients over 40's age, will enable more effective monitoring. Radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium.

A suggestion of Aortic wall Stiffness Evaluation Technique Independent on Changeable Blood Pressure : Aortic Distensibility Index (변화하는 혈압의 영향을 받지 않는 동맥 벽의 강화도 측정 방법 제안 : 대동맥 확장지수)

  • Seo, Jee-Hye;Choi, Dong-Ho;Wu, Zhuqing;Rienmueller, Rainer;Lee, Jong-Min
    • Journal of Biomedical Engineering Research
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    • v.29 no.2
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    • pp.151-158
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    • 2008
  • To evaluate aortic wall stiffness without influence of different background blood pressure, a new technique was developed and verified. At eight swine descending aortae, volume-pressure measurement was performed using custom-made system. Based on averaged pressure-volume curve, aortic distensibility index was formulated to evaluate aortic wall stiffness regardless of variable blood pressure and aortic size. The variability of aortic distensibility index by pressure change was compared with other parameters for wall stiffness evaluation. Subsequently, the aortic distensibility index was calculated at 100 contrast-enhanced EBCT data sets of normal volunteers in regular health screening program. The measured aortic distensibility index was compared with age, coronary calcium score, and aortic calcium score. Between 50 and 360 mmHg of blood pressure, the coefficient of variance of aortic distensibility index was 22.00% as comparing with 88.99% of classical compliance. Based on age, aortic distensibility index showed correlation coefficient of 0.55, whereas classical compliance showed 0.26. The correlation coefficient with modified aortic calcification was 0.43. Linear regression study revealed statistical significance of correlation coefficients. The aortic distensibility index, the method to evaluate aortic wall stiffness free from variable blood pressure and aortic size, was developed and verified with significant practical feasibility.

Detecting of Periodic Fasciculations of Avian Muscles Using Magnetic and Other Multimedia Devices

  • Nakajima, Isao;Tanaka, Sachie;Mitsuhashi, Kokuryo;Hata, Jun-ichi;Nakajima, Tomo
    • Journal of Multimedia Information System
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    • v.6 no.4
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    • pp.293-302
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    • 2019
  • In the past, there was a theory that influenza wasn't transmitted directly from birds but was infected to humans via swains. Recently, molecular level research has progressed, and it was confirmed that the avian influenza virus can directly infected to human lung and intestinal epithelial cells. Three pandemicsin the past 100 years were also infected to humans directly from birds. In view of such scientific background, we are developing a method for screening sick birds by monitoring the physiological characteristics of birds in a contactless manner with sensors. Here, the movement of respiratory muscles and abdominal muscles under autonomic innervation was monitored using a magnet and Hall sensor sewn on the thoracic wall, and other multimedia devices. This paper presents and discusses the results of experiments involving continuous periodic noise discovered during flight experiments with a data logger mounted on a Japanese pheasant from 2012 to 2015. A brief summary is given as the below: 1. Magnet and Hall sensor sewn to the left and right chest walls, bipolar electrocardiograms between the thoracic walls, posterior thoracic air sac pressure, angular velocity sensors sewn on the back and hips, and optical reflection of LEDs (blue and green) from the skin of the hips allow observation of periodic vibrations(fasciculations) in the waves. No such analysis has been reported before. 2. These fasciculations are presumed to be derived from muscle to maintain and control air sac pressure. 3. Since each muscle fiber is spatially Gaussian distributed from the sympathetic nerve, the envelope is assumed to plot a Gaussian curve. 4. Since avian trunk muscles contract periodically at all time, we assume that the sympathetic nerve dominates in their control. 5. The technique of sewing a magnet to the thoracic wall and measuring the strength of the magnetic field with a Hall sensor can be applied to screen for early stage of avian influenza, with a sensor attached to the chicken enclosure.

A Comparison of Different Depression Instruments for Stroke Patients (뇌졸중 환자의 우울증 평가도구 비교)

  • Lee, Dong-Jin;Shim, Jae-Kwang;An, Seung-Heon
    • The Journal of Korean Physical Therapy
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    • v.23 no.2
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    • pp.69-76
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    • 2011
  • Purpose: The aim of this study was to investigate the prevalence of depressive symptoms in stroke patients and to compare characteristics of different rating scales - Hamilton Depression Rating Scale (HDRS), Beck Depression Inventory (BDI) and Hospital Anxiety and Depression Scale-Depression (HAD.D)- with regard to diagnosis and severity assessment for post-stroke depression. Methods: Participants included 44 stroke patients who could communicate. At admission, all study participants received a semi-structured interview using the HDRS and a self-completed questionnaire using the BDI and the HAD-D. Pearson's correlation method was used to examine associations among the three depression scales. The BDI and HAD-D were compared based on HDRS criteria, and the sensitivity and specificity using cut-off values were analyzed. Results: The HDRS showed that 52.30% of stroke patients had depressive symptoms on the BDI and HAD-D it was 59.10%. The HDRS correlated significantly with the BDI (r=0.81, p<0.01) and HAD-D (r=0.55, p<0.01). The BDI correlated significantly with HADS (r=0.50, p<0.01). After calculating the area under the ROC curve to decide on HDRS criteria, the BDI (AUC=0.91, 95% CI: 0.83.0.99) showed a significantly larger area compared to the HAD.D (AUC=0.82, 95% CI: 0.69-0.94). The cut-off value of the BDI was 12.50 points with a sensitivity of 81.00% and a specificity of 76.20%. Conclusion: These findings show that the BDI is a useful screening test for depression that most closely predicts the HRDS score.