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Comparison of Convolutional Neural Network (CNN) Models for Lettuce Leaf Width and Length Prediction (상추잎 너비와 길이 예측을 위한 합성곱 신경망 모델 비교)

  • Ji Su Song;Dong Suk Kim;Hyo Sung Kim;Eun Ji Jung;Hyun Jung Hwang;Jaesung Park
    • Journal of Bio-Environment Control
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    • v.32 no.4
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    • pp.434-441
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    • 2023
  • Determining the size or area of a plant's leaves is an important factor in predicting plant growth and improving the productivity of indoor farms. In this study, we developed a convolutional neural network (CNN)-based model to accurately predict the length and width of lettuce leaves using photographs of the leaves. A callback function was applied to overcome data limitations and overfitting problems, and K-fold cross-validation was used to improve the generalization ability of the model. In addition, ImageDataGenerator function was used to increase the diversity of training data through data augmentation. To compare model performance, we evaluated pre-trained models such as VGG16, Resnet152, and NASNetMobile. As a result, NASNetMobile showed the highest performance, especially in width prediction, with an R_squared value of 0.9436, and RMSE of 0.5659. In length prediction, the R_squared value was 0.9537, and RMSE of 0.8713. The optimized model adopted the NASNetMobile architecture, the RMSprop optimization tool, the MSE loss functions, and the ELU activation functions. The training time of the model averaged 73 minutes per Epoch, and it took the model an average of 0.29 seconds to process a single lettuce leaf photo. In this study, we developed a CNN-based model to predict the leaf length and leaf width of plants in indoor farms, which is expected to enable rapid and accurate assessment of plant growth status by simply taking images. It is also expected to contribute to increasing the productivity and resource efficiency of farms by taking appropriate agricultural measures such as adjusting nutrient solution in real time.

Study on the Anti-bacterium, Antioxidant and Anti-inflammatory Effect of Calystegia pubescens Lindl. Extracts (메꽃(Calystegia pubescens Lindl.) 추출물의 항균, 항산화 및 항염증 효과에 관한 연구)

  • Ji-A Byeon;Un-Gyo Shin;Ye-Jin Jang;Su-Bin Hwang;Seon-A Lee;Gayeon Kim;Jin-Tae Lee;Ildae Song;Yong-Jin Kwon
    • Journal of the Korean Applied Science and Technology
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    • v.41 no.3
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    • pp.745-755
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    • 2024
  • Calystegia pubescens Lindl. (C. pubesens) is a native Korean herb that has been traditionally used for its diuretic, fatigue, and blood sugar-lowering effects. In previous studies, C. pubesens has shown antioxidant and whitening effects, but research on its antibacterial and anti-inflammatory properties is limited, and its potential as functional materials is lacking. In this study, we investigated the antibacterial, antioxidant, and anti-inflammatory effects of leaf (CPL) and stem (CPS) extracts of C. pubesens extracted with 70% ethanol. When the anti-bacterial effect was confirmed, CPL showed superior anti-bacterial effect than CPS for C. acne, S. aureus, E. coli and P. aeruginosa. Additionally, CPL exhibited significantly higher antioxidant activity compared to CPS, as demonstrated by DPPH and ABTS+ radical scavenging assays. Therefore, CPL showed superior anti-bacterial and antioxidant effects compared to CPS. Based on these results, further investigation was conducted to confirm the anti-inflammatory effect of CPL using RAW264.7 macrophages. Nitric oxide (NO) produced by lipopolysaccharide (LPS) stimulation was significantly reduced by CPL treatment in a dose-dependent manner. Additionally, the protein and mRNA expression of iNOS was reduced by CPL in LPS-indueced RAW264.7 cells, which was consistent with NO production. In conclusion, this study confirmed that CPL has superior anti-bacterial and antioxidant effects compared to CPS, and demonstrated anti-inflammatory effect of CPL via inhibiting iNOS expression and NO production induced by LPS. Based on the result, we suggest the potential of CPL as a valuable functional materials.

Effects of Adsorption and Decomposition on the Removal of Total Organic Carbon (TOC) in Oil Wastewater by Cellulose-based Pseudo Graphene and Persulfate (셀룰로오스 기반 유사-그래핀과 과황산염에 의한 압연류 폐수내 총유기탄소(TOC) 흡착 및 분해효과 연구)

  • Song-I Kim;Ji-Young Shin;Kyung-Chul Park;Jae-Kyu Yang;Dong-Su Kim
    • Journal of the Korea Organic Resources Recycling Association
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    • v.32 no.3
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    • pp.5-18
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    • 2024
  • Chemical oxygen demand (COD), an organic material measurement index, has a limit to the management of the total amount of all organic materials including non-degradable organic materials due to low oxidation rate. So total organic carbon (TOC) that can measure organic materials more accurately is introduced and used as a measurement index. Several environmental companies including company A in Gyeonggi-do dilute raw wastewater first and then treats it with chemicals. And an activated carbon is used at the rear stage to treat total organic carbon even though various treatment processes can be applied to reduce TOC in wastewater. There are some problems such as use of a lot of diluting water and generation of an excessive amount of sludge, so it is urgent to come up with an alternative plan. Therefore, in this study, an application experiment was conducted on two different methods for improving the TOC reduction efficiency of waste water from Company A. The first method is the evaluation of the substitution potential of powered activated carbon(PAC), an adsorbent currently used, by manufacturing cellulose-based graphene like carbon (CGLC). This first study showed that CGLC had about 10% higher TOC adsorption efficiency than commercial PAC, showing the possibility of being applied as an alternative adsorbent for PAC in water treatment sites. The second method relates to the removal of TOC by sulfate radials produced by persulfate (PS) activation. Two activation methods were applied: using CGLC and PAC as carbon-based catalyst and using the high temperature of wastewater for PS activation. As a result of using PAC and CGLC as PS activation materials, the TOC removal rate was lower than the adsorption amount of TOC by CGLC and PAC due to excessive chlorine ions present in the real wastewater. However, as a result of using the high water temperature (55~60℃) of the field wastewater for PS activation, it showed a much greater TOC removal efficiency than PAC alone, CGLC alone, and using a carbon-based catalyst for PS activation. When PS was injected more than 0.5%, it showed a TOC removal efficiency of 95% or more within 24 hr. In addition, when PS was injected more than 0.3%, the TOC concentration could be lowered to less than 75 ppm, which is the wastewater discharge standard applied to company A. When these results were summarized, raw wastewater of high temperature can be treated with a simple process of only adding of PS and discharged by treating TOC below the wastewater discharge standard applied to company A.

The Clinical Significance of ${\gamma}{\delta}$ T lymphocytes in patients with pleural tuberculosis (결핵환자에서 말초혈액과 흉막액내 ${\gamma}{\delta}$ T 림프구의 의의)

  • Song, Kwang Seon;Shin, Kye Chul;Kim, Do Hun;Hong, Ae Ra;Kim, Hee Seon;Yong, Suk Joong
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.1
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    • pp.44-51
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    • 1997
  • Background : The changes of the composition in the T-lymphocyte are important as an immunological abnormality in the pathogenesis of tuberculosis. Previously, the second type of TCR dimer(${\gamma}{\delta}$ T lymphocyte) that did not express CD4 or CD8 molecules was found. In other reports the presence of this type of lymphocytes was increased in the initial stage of tuberculous infections. Method : To determine whether there are some differences in the T-lymphocyte subsets in the peripheral blood or pleural effusion between pleural tuberculosis and other pleurisy. Thirty patients with pleural effusion among the forty-nine patients were examined T-lymphocyte subset analysis(CD4+T-cell,CD8+ T-cell,${\gamma}{\delta}$ T-lymphocytes) with anti- Leu4, anti-Leu3a, anti-Lea2a, anti HLA-DR and anti-TCR-${\gamma}{\delta}$-1(Becton & Dickinson Co.). Results : The average age of the patients was 50 years old(17-81year). There were 33 males and 16 female patients. Patiensts with tuberculosis are 30cases(tuberculous pleurisy 15), lung cancer 12cases(malignant effusion 9) and pneumonia 7cases(parapneumonic effusion 6cases) In T lymphocyte subsets of pleural effusion, helper T lymphocyte(54.6 + 13.8 %) of tuberculous pleurisy was higher than that(36.2 + 25.3 %) of non-tuberculous pleurisy(p=0.04). The peripheral blood ${\gamma}{\delta}$ T-lymphocytes in tuberculousis was insignificantly higher than non-tuberculous patients(p= 0.24). The peripheral blood ${\gamma}{\delta}$ T-lymphocytes and pleural ${\gamma}{\delta}$ T-Iymphocytes in tuberculous pleurisy was insignificantly higher than in non-tuberculous pleurisy(p= 0.16, p= 0.12). Conclusion : The percentage of -${\gamma}{\delta}$ T lymphocytes among the total T-lymphocytes is not significantly increased in the peripheral blood or pleural effusion of the pleural tuberculosis. ${\gamma}{\delta}$ T lymphocytes is less useful as a diagnostic method of pleural tuberculosis.

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Comparison of Treatment Planning System(TPS) and actual Measurement on the surface under the electron beam therapy with bolus (전자선 치료 시 Bolus를 적용한 경우 표면선량의 Treatment Planning System(TPS) 계산 값과 실제 측정값의 비교)

  • Kim, Byeong Soo;Park, Ju Young;Park, Byoung Suk;Song, Yong Min;Park, Byung Soo;Song, Ki Weon
    • The Journal of Korean Society for Radiation Therapy
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    • v.26 no.2
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    • pp.163-170
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    • 2014
  • Purpose : If electron, chosen for superficial oncotherapy, was applied with bolus, it could work as an important factor to a therapy result by showing a drastic change in surface dose. Hence the calculation value and the actual measurement value of surface dose of Treatment Planning System (TPS) according to four variables influencing surface dose when using bolus on an electron therapy were compared and analyzed in this paper. Materials and Methods : Four variables which frequently occur during the actual therapies (A: bolus thickness - 3, 5, 10 mm, B: field size - $6{\time}6$, $10{\time}10$, $15{\time}15cm2$, C: energy - 6, 9, 12 MeV, D: gantry angle - $0^{\circ}$, $15^{\circ}$) were set to compare the actual measurement value with TPS(Pinnacle 9.2, philips, USA). A computed tomography (lightspeed ultra 16, General Electric, USA) was performed using 16 cm-thick solid water phantom without bolus and total 54 beams where A, B, C, and D were combined after creating 3, 5 and 10 mm bolus on TPS were planned for a therapy. At this moment SSD 100 cm, 300 MU was investigated and measured twice repeatedly by placing it on iso-center by using EBT3 film(International Specialty Products, NJ, USA) to compare and analyze the actual measurement value and TPS. Measured film was analyzed with each average value and standard deviation value using digital flat bed scanner (Expression 10000XL, EPSON, USA) and dose density analyzing system (Complete Version 6.1, RIT, USA). Results : For the values according to the thickness of bolus, the actual measured values for 3, 5 and 10 mm were 101.41%, 99.58% and 101.28% higher respectively than the calculation values of TPS and the standard deviations were 0.0219, 0.0115 and 0.0190 respectively. The actual values according to the field size were $6{\time}6$, $10{\time}10$ and $15{\time}15cm2$ which were 99.63%, 101.40% and 101.24% higher respectively than the calculation values and the standard deviations were 0.0138, 0.0176 and 0.0220. The values according to energy were 6, 9, and 12 MeV which were 99.72%, 100.60% and 101.96% higher respectively and the standard deviations were 0.0200, 0.0160 and 0.0164. The actual measurement value according to beam angle were measured 100.45% and 101.07% higher at $0^{\circ}$ and $15^{\circ}$ respectively and standard deviations were 0.0199 and 0.0190 so they were measured 0.62% higher at $15^{\circ}$ than $0^{\circ}$. Conclusion : As a result of analyzing the calculation value of TPS and measurement value according to the used variables in this paper, the values calculated with TPS on 5 mm bolus, $6{\time}6cm2$ field size and low-energy electron at $0^{\circ}$ gantry angle were closer to the measured values, however, it showed a modest difference within the error bound of maximum 2%. If it was beyond the bounds of variables selected in this paper using electron and bolus simultaneously, the actual measurement value could differ from TPS according to each variable, therefore QA for the accurate surface dose would have to be performed.

Dose Response Relationship in Local Radiotherapy for Hepatocellular Carcinoma (원발성 간암의 국소 방사선치료 시 선량반응 관계)

  • Park Hee Chul;Seong Jinsil;Han Kwang Hyub;Chon Chae Yoon;Moon Young Myoung;Song Jae Seok;Suh Chang Ok
    • Radiation Oncology Journal
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    • v.19 no.2
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    • pp.118-126
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    • 2001
  • Purpose : In this study, it was investigated whether dose response relation existed or not in local radiotherapy for primary hepatocellular carcinoma. Materials and Methods : From January 1992 to March 2000, 158 patients were included in present study. Exclusion criteria included the presence of extrahepatic metastasis, liver cirrhosis of Child's class C, tumors occupying more than two thirds of the entire liver, and performance status on the ECOG scale of more than 3. Radiotherapy was given to the field including tumor with generous margin using 6, 10-MV X-ray. Mean tumor dose was $48.2{\pm}7.9\;Gy$ in daily 1.8 Gy fractions. Tumor response was based on diagnostic radiologic examinations such as CT scan, MR imaging, hepatic artery angiography at $4\~8$ weeks following completion of treatment. Statistical analysis was done to investigate the existence of dose response relationship of local radiotherapy when it was applied to the treatment of primary hepatocellular carcinoma. Results : An objective response was observed in 106 of 158 patients, giving a response rate of $67.1\%$. Statistical analysis revealed that total dose was the most significant factor in relation to tumor response when local radiotherapy was applied to the treatment of primary hepatocellular carcinoma. Only $29.2\%$ showed objective response in patients treated with dose less than 40 Gy, while $68.6\%\;and\;77.1\%$ showed major response in patients with $40\~50\;Gy$ and more than 50 Gy, respectively. Child-Pugh classification was significant factor in the development of ascites, overt radiation induced liver disease and gastroenteritis. Radiation dose was an important factor for development of radiation induced gastroduodenal ulcer. Conclusion : Present study showed the existence of dose response relationship in local radiotherapy for primary hepatocellular carcinoma. Only radiotherapy dose was a significant factor to predict the objective response. Further study is required to predict the maximal tolerance dose in consideration of liver function and non-irradiated liver volume.

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A Prospective Randomized Comparative Clinical Trial Comparing the Efficacy between Ondansetron and Metoclopramide for Prevention of Nausea and Vomiting in Patients Undergoing Fractionated Radiotherapy to the Abdominal Region (복부 방사선치료를 받는 환자에서 발생하는 오심 및 구토에 대한 온단세트론과 메토클로프라미드의 효과 : 제 3상 전향적 무작위 비교임상시험)

  • Park Hee Chul;Suh Chang Ok;Seong Jinsil;Cho Jae Ho;Lim John Jihoon;Park Won;Song Jae Seok;Kim Gwi Eon
    • Radiation Oncology Journal
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    • v.19 no.2
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    • pp.127-135
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    • 2001
  • Purpose : This study is a prospective randomized clinical trial comparing the efficacy and complication of anti-emetic drugs for prevention of nausea and vomiting after radiotherapy which has moderate emetogenic potential. The aim of this study was to investigate whether the anti-emetic efficacy of ondansetron $(Zofran^{\circledR})$ 8 mg bid dose (Group O) is better than the efficacy of metoclopramide 5 mg lid dose (Group M) in patients undergoing fractionated radiotherapy to the abdominal region. Materials and Methods : Study entry was restricted to those patients who met the following eligibility criteria: histologically confirmed malignant disease; no distant metastasis; performance status of not more than ECOG grade 2; no previous chemotherapy and radiotherapy. Between March 1997 and February 1998, 60 patients enrolled in this study. All patients signed a written statement of informed consent prior to enrollment. Blinding was maintained by dosing identical number of tablets including one dose of matching placebo for Group O. The extent of nausea, appetite loss, and the number of emetic episodes were recorded everyday using diary card. The mean score of nausea, appetite loss and the mean number of emetic episodes were obtained in a weekly interval. Results : Prescription error occurred in one patient. And diary cards have not returned in 3 patients due to premature refusal of treatment. Card from one patient was excluded from the analysis because she had a history of treatment for neurosis. As a result, the analysis consisted of 55 patients. Patient characteristics and radiotherapy characteristics were similar except mean age was $52.9{\pm}11.2$ in group M, $46.5{\pm}9.5$ in group O. The difference of age was statistically significant. The mean score of nausea, appetite loss and emetic episodes in a weekly interval was higher in group M than O. In group M, the symptoms were most significant at 5th week. In a panel data analysis using mixed procedure, treatment group was only significant factor detecting the difference of weekly score for all three symptoms. Ondansetron $(Zofran^{\circledR})$ 8 mg bid dose and metoclopramide 5 mg lid dose were well tolerated without significant side effects. There were no clinically important changes In vital signs or clinical laboratory parameters with either drug. Conclusion : Concerning the fact that patients with younger age have higher emetogenic potential, there are possibilities that age difference between two treatment groups lowered the statistical power of analysis. There were significant difference favoring ondansetron group with respect to the severity of nausea, vomiting and loss of appetite. We concluded that ondansetron is more effective anti-emetic agents in the control of radiotherapy-induced nausea, vomiting, loss of appetite without significant toxicity, compared with commonly used drug, i.e., metoclopramide. However, there were patients suffering emesis despite the administration of ondansetron. The possible strategies to improve the prevention and the treatment of radiotherapy-induced emesis must be further studied.

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Chest CT Finding and Its Comparison with Bronchoscopic Finding in Endobronchial Tuberculosis (기관지결핵의 흉부전산화단층촬영소견 및 기관지경소견과의 비교)

  • Lee, Jae-Ho;Yoon, Hye-Kyung;Song, Jae-Woo;Yoo, Chul-Gyu;Chung, Hee-Soon;Kim, Young-Hwan;Han, Sung-Koo;Shim, Young-Soo
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.4
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    • pp.742-755
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    • 1997
  • Background : Endobronchial tuberculosis(ET) is still relatively common disease in Korea. We intended to evaluate the length of endobronchial lesion, peribronchial thickness, luminal irregularity and associated mediastinal lymph node enlargement with Chest CT to get information for such aggressive treatment as electrocautery, laser therapy and so on of bronchial stricture in ET, and also to compare the change of Chest CT finding with that of bronchoscopic finding after one month of anti-tuberculosis treatment. Method : We performed CT in 26 patients who were diagnosed as ET by bronchoscopy at Boramae Hospital from November 1991 to March 1996. After classifying ET into seven subtypes according to bronchoscopic finding, we analyzed the CT finding of each subtype. And we followed up the bronchoscopy, CT, and PIT after one month of anti-tuberculosis treatment, and compared the change of CT findings with those of bronchoscopic findings in nine patients. Results : Age of the patients was from 17 to 73 years old, and the ratio of male to female was 1 : 25 with absolute female predominance. The site(s) of bronchial involvement by tuberculosis is one in 14 cases, two in nine cases and three in one case, respectively, and the left main bronchus was the most frequently involved site (13 cases for multiple involvements and 7 cases for single involvement among 26 cases). The length of bronchial involvement by tuberculosis which was measured by CT was from 10 to 55 mm, and there was a tendency that the length of involved lesion in fibrostenotic type was shorter than that of actively caseating type. Bronchial stricture on CT was noticed in 25 (96%) cases and the range of severity was from total occlusion to near-normal and also showed wide variation even though the subtype of ET was same. The increase of peribronchial thickness which was measured by CT, was noticed in 21 cases (91%) among 23 cases (in which the measurement was possible), and there was no improvement of peribronchial thickness in those cases which showed little improvement in bronchial stricture despite anti-tuberculosis treatment. There was no difference in the luminal irregularity of involved bronchi on CT in relation to bronchoscopic subtypes. The mediastinal lymph node enlargement, defined as the diameter of lymph node was larger than 1cm on CT, was detected in 20 cases (77%), and right side was more frequently involved (L : R = 1 : 5.2). The CT finding usually showed extrinsic bronchial compression but showed direct invasion in two cases which were bronchoscopically classified as tumorous type. When follow-up bronchoscopy and CT was performed after one month of anti-tuberculosis treatment in nine patients, CT showed significant improvement in peribronchial thickness and mediastinal lymph node enlargement. Bronchial stricture was also improved in 6 cases but aggravated in 3 cases despite anti-tuberculosis therapy. In two cases which were classified as fibrostenotic type by bronchoscopy, CT showed significant improvement in bronchial stricture, interestingly. Conclusion : We concluded that the role of Chest CT was complimentary to bronchoscopy in ET, since CT was useful in evaluating the length of bronchial involvement, peribronchial thickness, and mediastinal lymph node enlargement.

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A Comparative Analysis of GBEF According to Image Aquisition Method in Hepatobiliary Scan (간담도스캔의 영상수집방법에 따른 담즙배출율의 비교분석)

  • Kim, Yeong-Seon;Seo, Myeong-Deok;Lee, Wan-Kyu;Song, Jae-Beom
    • The Korean Journal of Nuclear Medicine Technology
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    • v.18 no.2
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    • pp.8-16
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    • 2014
  • Purpose The quantitative analysis of gallbladder emptying is very important in diagnosis of motility disorder of gallbladder and in biliary physiology. The GBEF obtain the statics aquisition method or the dynamic acquisition method in two ways. The purpose of this study is to compare the GBEF value of statics acquisition method and the dynamic acquisition method. And we find the best way for calculate GBEF. Materials and Methods The quantitative hepatobiliary scan with $^{99m}Tc$-mebrofenin was performed of 27 patients. Initial images were acquired statically, for 60 min after injection of the radioactive tracer. And if the gallbladder is visualized to 60 min, performed stimulation of gallbladder (1egg, 200 mL milk). After that, started acquisition of dynamic image for 30 min. After that, image of after fatty meal of the statics method were acquired on equal terms with 60 min image. The statics GBEF was calculated using the images of before fatty meal and post fatty meal by the statics method. The dynamic GBEF was calculated using the images of time of maximum bile juice uptake ($T_{max}$) and time of minimum bile juice uptake ($T_{min}$) images from the gallbladder time-activity curve. A bile juice is secreted from gallbladder while eating a fatty meal. that is named early GBEF and that was calculated using before fatty meal image of the statics method and 1 min image of the dynamic method. Results The result saw very big difference between two according to $T_{max}$. The result, were as follows. 1) In case of less than 1 min, the dynamic mean GBEF was $40.1{\pm}21.7%$, the statics mean GBEF was $51.5{\pm}23.6%$ in 16 cases. The early mean GBEF was $14.0{\pm}29.1%$. The GBEF of statics method was higher because that include secreted bile juice while performed stimulation of gallbladder. A difference of GB counts according to acquisition method and the early bile juice counts was $17.6{\pm}14.8%$ and $13.5{\pm}15.3%$. 2) In case of exceed than 1 min, the dynamic mean GBEF was $31.0{\pm}19.7%$, the statics mean GBEF was $21.3{\pm}19.4%$ in 7 cases. The early GBEF was $-6.9{\pm}4.9%$. The GBEF of dynamic method was higher because that include concentrated bile juice to $T_{max}$. A difference of GB counts according to acquisition method and the early bile juice counts was $14.3{\pm}7.3%$ and $5.9{\pm}3.9%$. Conclusion The statics method is very easy and simple, but in case of $T_{max}$ delay, the GBEF can be lower. The dynamic method is able to calculate accurately in case of $T_{max}$ delay, but in case of $T_{max}$ is less than 1 min, the GBEF can be lower because dynamic GBEF exclude secreted bile juice while performed stimulation of gallbladder. The best way to calculate GBEF is to scan with dynamic method preferentially and to choose suitable method between the two way after conform $T_{max}$ on the T-A curve of the dynamic method.

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Measuring Intracellular Mycobacterial Killing Using a Human Whole Blood Assay (인체 전혈 모델을 이용한 세포내 결핵균 살균력에 관한 연구)

  • Cheon, Seon-Hee;Song, Ho-Yeon;Lee, Eun-Hee;Oh, Hee-Jung;Kang, In-Sook;Cho, Ji-Yoon;Hong, Young-Sun
    • Tuberculosis and Respiratory Diseases
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    • v.53 no.5
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    • pp.497-509
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    • 2002
  • Background : The mechanisms through which cellular activation results in intracellular mycobacterial killing is only partially understood. However, in vitro studies of human immunity to Mycobacterium tuberculosis have been largely modeled on the work reported by Crowle, which is complicated by several factors. The whole blood culture is simple and allows the simultaneous analysis of the relationship between bacterial killing and the effect of effector cells and humoral factors. In this study, we attempted to determine the extent to which M. tuberculosis is killed in a human whole blood culture and to explore the role of the host and microbial factor in this process. Methods : The PPD positive subject were compared to the umbilical cord blood and patients with tuberculosis, diabetes and lung cancer. The culture is performed using heparinized whole blood diluted with a culture medium and infected with a low number of M. avium or M. tuberculosis $H_{37}Ra$ for 4 days by rotating the culture in a $37^{\circ}C$, 5% $CO_2$ incubator. In some experiments, methlprednisolone- or pentoxifyline were used to inhibit the immune response. To assess the role of the T-cell subsets, CD4+, CD8+ T-cells or both were removed from the blood using magnetic beads. The ${\Delta}$ log killing ratio was defined using a CFU assay as the difference in the log number of viable organisms in the completed culture compared to the inoculum. Results : 1. A trend was noted toward the improved killing of mycobacteria in PPD+ subjects comparing to the umbilical cord blood but there was no specific difference in the patients with tuberculosis, diabetes and lung cancer. 2. Methylprednisolone and pentoxifyline adversely affected the killing in the PPD+ subjects umbilical cord blood and patients with tuberculosis. 3. The deletion of CD4+ or CD8+ T-lymphocytes adversely affected the killing of M. avium and M. tuberculosis $H_{37}Ra$ by PPD+ subjects. Deletion of both cell types had an additive effect, particularly in M. tuberculosis $H_{37}Ra$. 4. A significantly improved mycobacterial killing was noted after chemotherapy in patients with tuberculosis and the ${\Delta}$ logKR continuously decreased in a 3 and 4 days of whole blood culture. Conclusion : The in vitro bactericidal assay by human whole blood culture model was settled using a CFU assay. However, the host immunity to M. tuberculosis was not apparent in the human whole blood culture bactericidal assay, and patients with tuberculosis showed markedly improved bacterial killing after anti-tuberculous chemotherapy compared to before. The simplicity of a whole blood culture facilitates its inclusion in a clinical trial and it may have a potential role as a surrogate marker in a TB vaccine trial.