• The Korean Journal of Nuclear Medicine
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• v.35 no.3
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• pp.185-191
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• 2001

Objectives: Recently, $[methyl-^{11}C]-({\beta}$-Hydroxyethyl)trimethylammonium ($[^{11}C]$choline) Has been discovered to be a very effective tracer in imaging various human tumors using positron omission tomography. Because of the short half-life of C-11, it is very difficult to use in a routine imaging procedure and needs a frequent synthesis of $[^{11}C]$choline. This can be supplemented by the substitution of $[^{11}C]$choline with $[methyl-^{18}F]$fluorocholine. Here, we would like to report ceil uptake and biodistribution of $[^{11}C]$choline and $[^{18}F]$fluorocholine as a basic study. Methods: $[^{11}C]$Choline was prepared by the treatment of $[^{11}C]CH_3I$ with N,N-dimethylaminoethanol and $[^{18}F]$fluorocholine was synthesized from reaction of $CH_2Br[^{18}F]F$ with N,N-dimethylaminoethanol. The radiochemical purity was checked by high performance liquid chromatography (HPLC). The blodistribution of $[^{11}C]$choline and $[^{18}F]$fluorocholine was determined in balb/c mouse at 5 min, 20 min, 40 min and 80 min. The cell uptake was measured using glioma (9L) and colon adenocarcinoma (SW620). Results: The radiochemical purity was more than 98% after purification. In the liver, uptake did not change over time; the uptake was 20%ID/g for $[^{11}C]$choline and 13%ID/g for $[^{18}F]$fluorocholine. In the kidney, radioactivity decreased over time; the uptake was 15%ID/g for $[^{11}C]$choline and 20%ID/g for $[^{18}F]$fluorocholine, 80 min post-injection. The cell uptake of $[^{11}C]$choline was 4.93% for glioma (9L) and 18.69% for colon adenocarcinoma (SW620). For $[^{18}F]$fluorocholine, 1.77% for glioma (9L) and 2.77% for colon adenocarcinoma (SW620). Conclusion: $[^{11}C]$Choline and $[^{18}F]$fluorocholine showed a different cell uptake tendency, depending on cancer cell line.

• Radiation Oncology Journal
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• v.29 no.2
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• pp.71-82
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• 2011

Purpose: To evaluate the biochemical control rate and the rate of side effects after performing permanent brachytherapy of localized prostate cancer. Materials and Methods: 67 patients with localized prostate cancer were treated with brachytherapy between April 2007 and December 2008. Of these, 43 patients who were followed up and did not receive external radiotherapy were evaluated for the change in prostate specific antigen (PSA) level and the occurrence of side effects. In total, 18 patients were classified as low risk, 19 patients as intermediate risk, and 6 patients as high risk. The prescription dose was 145 Gy. Results: A PSA increase greater than 2 ng/mL occurred in 2 patients (4.7%). Radiation Therapy Oncology Group (RTOG) grade 1 and 2 acute urologic complications (UC) occurred in 40 and 3 patients, respectively. Further, 5 patients had RTOG grade 1 acute rectal complication (RC). The numbers of RTOG grade 1, 2, and 3 chronic UC were 1, 4, and 1, respectively. The numbers of RTOG grade 1, 2, and 4 chronic RC were 5, 10, and 3, respectively. The statistically significant risk factors (RF) of acute RC were the minimal dose in the most irradiated 0.1 cc volume ($D_{0.1cc}$, p=0.041) and absolute volume receiving 150% of the prescribed dose ($V_{150cc}$, p=0.038) in the entire rectum (ER). The percentage ($V_{100%}$, p=0.019) and absolute volume ($V_{100cc}$, p=0.047) in the involved rectum (IR) were also statistically significant. The RF of chronic RC were $V_{100%}$ (p=0.011) in the ER and the $D_{0.1cc}$ (p=0.049), $V_{100cc}$ (p=0.023) in the IR. The number of used seeds were related with acute UC (p=0.028). Conclusion: Permanent brachytherpy of localized prostate cancer showed a favorable short term biochemical control rate. As such, selective intermediate and high risk patients can be managed with permanent brachytherapy. The effort to reduce rectal complication is also necessary.

• Childhood Kidney Diseases
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• v.15 no.1
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• pp.66-75
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• 2011

Purpose: Early diagnosis and treatment of febrile urinary tract infection (UTI) in children is important to prevent kidney damage. This study aims to evaluate the relationship between the presence of pyuria, the severity, and underlying genitourinary anomalies in patients with UTI. Methods: We retrospectively reviewed 293 patients with febrile UTI who were admitted to Korea University Guro Hospital during the period from June, 2007 until January, 2010. We divided the patients into two groups, one with the finding of pyuria at admission, and the other without, and compared the fever duration, white blood cell counts (WBC) and C-reactive protein (CRP) in peripheral bloods, hydronephrosis, cortical defects, vesicoureteral reflux and admission period. Results: Among the 293 patients with febrile UTI, 189 patients showed findings of pyuria whereas 104 patients did not. Patients with pyuria showed an increment of WBC ($14,694{\pm}485.2$ vs. $11,374{\pm}451.2/uL$, P <0.05) and CRP ($46.9{\pm}3.9$ vs $17.1{\pm}3.6$ mg/L, P <0.05) in peripheral blood sample. The presence of cortical defects (21.7 Vs 5.8%, P <0.05) and vesicoureteral reflux (15.9 Vs 6.7%, P <0.05) was also increased in patients with pyuria compared to patients without pyuria. There were no specific differences in fever duration, admission period, and hydronephrosis. Within the group with pyuria, CRP in peripheral blood sample increased proportionally with the increment of pyuria (P <0.05). Conclusion: In patients with febrile UTI, the increment of WBC in the urine sample can be a helpful predictor for increased CRP in peripheral blood and acute pyelonephritis.

• Journal of Korean Society of Transportation
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• v.22 no.1 s.72
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• pp.43-62
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• 2004

Conventionally the estimation method of the origin-destination Matrix has been developed by implementing the expansion of sampled data obtained from roadside interview and household travel survey. In the survey process, the bigger the sample size is, the higher the level of limitation, due to taking time for an error test for a cost and a time. Estimating the O-D matrix from observed traffic count data has been applied as methods of over-coming this limitation, and a gradient model is known as one of the most popular techniques. However, in case of the gradient model, although it may be capable of minimizing the error between the observed and estimated traffic volumes, a prior O-D matrix structure cannot maintained exactly. That is to say, unwanted changes may be occurred. For this reason, this study adopts a conjugate gradient algorithm to take into account two factors: estimation of the O-D matrix from the conjugate gradient algorithm while reflecting the prior O-D matrix structure maintained. This development of the O-D matrix estimation model is to minimize the error between observed and estimated traffic volumes. This study validates the model using the simple network, and then applies it to a large scale network. There are several findings through the tests. First, as the consequence of consistency, it is apparent that the upper level of this model plays a key role by the internal relationship with lower level. Secondly, as the respect of estimation precision, the estimation error is lied within the tolerance interval. Furthermore, the structure of the estimated O-D matrix has not changed too much, and even still has conserved some attributes.

• Tuberculosis and Respiratory Diseases
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• v.40 no.1
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• pp.23-28
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• 1993

Background: Since an important component of carcinogenesis is unregulated growth, many investigators have reported the methods to detect cell proliferation in tissues including PCNA. PCNA is a 36 Kd intranuclear polypeptide and plays a critical role in cell proliferation. Thus progressive dysregulation of proliferation during carcinogenesis can be directly visualized in the paraffin embedded tissue using immunohistochemistry for PCNA which has an advantage of simplicity and maintenance of tissue architecture. The heterogeneity of PCNA expression is known to be related with proliferating fraction, histologic grade, DNA ploidy, and susceptibility of anticancer drugs, etc. We analyzed the biologic significance of the expression of PCNA in lung cancer tissues. Method: 43 lung cancer tissues, which were resected by surgery and were embedded in paraffin, were stained immunohistochemically by one hour MicroProbe System and the results were corelated with cell type, stage, site and survival. Result: 1) Suamous cell type showed high positivity (89%) than in adenocarcinoma (54%). 2) No significant difference related to tumor stage was noticed. 3) No significant difference between primary site and metastatic site was noticed. 4) No significant difference in 12-month survival between positive group and negative group was noticed. Conclusion: From this study, we concluded that imunohistochemistry for PCNA expression of routinely processed tissue is a simple technique for the assessment of proliferation in non-small cell lung cancer. Whether the labelling index has an independent prognostic value and deserves special attention in pathobiological evaluation in lung cancer remains to be investigated from large series with longer follow-up and to be correlated with multiple biological markers.

• Childhood Kidney Diseases
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• v.6 no.2
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• pp.142-154
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• 2002

Purpose : One of the most important adverse effects of long-term cyclosporine therapy is nephrotoxicity, the morphologic changes of which include interstitial fibrosis and arteriolar hyalinization. Recently, several authors have shown that osteopontin plays an important role in the development of interstitial fibrosis by acting as a macrophage chemoattractant and stimulating the production of $TGF-{\beta}$ in experimental cyclosporine nephrotoxicity. However, the relationship between osteopontin and $TGF-{\beta}$ in humans has not been clearly documented so far. We studied the expression of osteopontin and $TGF-{\beta}$ in children with minimal change nephrotic syndrome treated with cyclosporine to demonstrate whether there is a relationship between cyclosporine toxicity and osteopontin expression as previously shown in animal models. Materials and methods : Nineteen children (15 males and 4 females) were the subject of this study. Renal biopsies had been performed before and after the cyclosporine therapy (mean duration: 15.9 months). In 5 patients, additional biopsies were performed after completing the cyclosporine treatment (mean; 26 months). The expressions of osteopontin and $TGF-{\beta}$ were evaluated by immunohistochemistry in the glomeruli and tubulointerstitium. Results : Osteopontin expression was significantly increased in the glomerular mesangium and tubules after cyclosporine treatment. But there was no statistically significant increase of $TGF-{\beta}$ in the interstitium. There was no significant increase in tubular osteopontin and interstitial $TGF-{\beta}$ expression in those cases developing interstitial fibrosis after cyclosporine treatment compared with cases those not developing interstitial fibrosis. No significant changes in osteopontin or $TGF-{\beta}$ expression were observed in subsequent 5 biopsy samples after discontinuation of cyclosporine compared with the first follow up biopsies. Conclusion : These results suggest that osteopontin is a nonspecific marker of renal injury rather than a mediator of interstitial fibrosis in cyclosporine nephrotoxicity of human.

• The Korean Journal of Nuclear Medicine Technology
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• v.21 no.2
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• pp.44-48
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• 2017

Purpose Estradiol (E2) is a steroid hormone mainly produced in women and is a useful indicator for diagnosis of gynecological diseases, menstrual cycle, menopause, and precocious puberty. E2 measurement is performed by diluting the $^{125}I$ radioactive tracer and tracer buffer in the kit. However, It was not precisely specified when the period of tracer is available after activating. The purpose of this study was to determine the appropriate dilution time based on the measurement value with dilution time. Materials and Methods From December 2016 to February 2017, 60 E2 samples with concentrations ranging from 8 to 4577 pg/mL were divided into low, medium, and high concentrations. Dilution of the $^{125}I$ tracer was performed on a 230 RPM agitator for 30 minutes, 1 hour 30 minutes, and 2 hours 30 minutes, respectively. 24 hour dilution was gently shaken and refrigerated. To verify the difference and significance of the results according to the dilution time, a test of normality was performed using SPSS 18.0 and analyzed by Kruskal-Wallis test. The measured value according to the dilution time was compared with the interquartile range of the absolute error. Results The results of Kruskal-Wallis test were not significant (P>0.05). Measurement results are showed as interquartile range of absolute error. At low concentration, it is 0.052 between 1 hour 30 minutes and 2 hours 30 minutes, and 0.105 between 30 minutes and 1 hour 30 minutes. At medium concentration, 0.062 between 30 minutes and 1 hour 30 minutes, and 0.038 between 1 hour 30 minutes and 2 hours 30 minutes. At high concentration, it is 0.029 between 1 hour 30 minutes and 2 hours 30 minutes, and 0.06 between 2 hours 30 minutes and 24 hours. Conclusion There were no statistically significant differences. However, the change in the measured value is the smallest between 1 hour and 30 minutes to 2 hours and 30 minutes. Therefore, we recommend diluting time between 1 hour 30 minutes and 2 hours 30 minutes.

• Journal of Korean Society of Transportation
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• v.22 no.7 s.78
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• pp.155-159
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• 2004

Recently, there are many trials about Artificial neural networks : ANNs structure and studying method of researches for forecasting traffic volume. ANNs have a powerful capabilities of recognizing pattern with a flexible non-linear model. However, ANNs have some overfitting problems in dealing with a lot of parameters because of its non-linear problems. This research deals with the application of a variety of model selection criterion for cancellation of the overfitting problems. Especially, this aims at analyzing which the selecting model cancels the overfitting problems and guarantees the transferability from time measure. Results in this study are as follow. First, the model which is selecting in sample does not guarantees the best capabilities of out-of-sample. So to speak, the best model in sample is no relationship with the capabilities of out-of-sample like many existing researches. Second, in stability of model selecting criterion, AIC3, AICC, BIC are available but AIC4 has a large variation comparing with the best model. In time-series analysis and forecasting, we need more quantitable data analysis and another time-series analysis because uncertainty of a model can have an effect on correlation between in-sample and out-of-sample.

• Tuberculosis and Respiratory Diseases
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• v.66 no.3
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• pp.205-210
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• 2009

Background: CXCL10 and CXCL11, which are family of CXCR3 ligands, are expressed by lymphocytes and even by bronchial epithelial cells if the cellular immunity is activated. This study evaluated the potential utility of CXCL10 and CXCL11 in the serum for active pulmonary tuberculosis in comparison with lung cancer, which activates the cellular immunity, and benign lung diseases. Methods: Patients who newly visited Pusan National University Hospital from January 2007 to December 2007 and were suspected of having lung cancer or tuberculosis were enrolled prospectively. The patients were classified pathologically and clinically into three groups, 47 with lung cancer, 18 with active pulmonary tuberculosis and 38 control patients with benign pulmonary disease. ELISA was used to determine the levels of CXCL10 and CXCL11 were determined in the serum. Results: The level of CXCL10 and CXCL11 were significantly higher in the active pulmonary tuberculosis group than in the lung cancer and benign lung disease groups (p<0.001, Kruskal-Wallis). The level of CXCL11 was significantly higher in the lung cancer group than in the benign pulmonary disease group, but there was no significant difference in level of CXCL10 between the three groups (p<0.001, p=0.655, respectively, Mann-Whitney U). The level of CXCL10 in patients with stage III+IV lung cancer was significantly higher than those with stage I+II, but there was no significant difference in the level of CXCL11 between the groups (p<0.001, p=0.07, respectively, Mann-Whitney U). There was no significant difference in the level of CXCL10 and CXCL11 between those with the presence and absence of lung cancer metastasis. There was a significant correlation between the level of CXCL10 and CXCL11 (r=0.223, p<0.001). Conclusion: CXCL10 and CXCL11 may be a potential useful markers for active pulmonary tuberculosis if used alongside other diagnostic methods.

• Journal of the Korean earth science society
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• v.28 no.2
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• pp.169-178
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• 2007

In this research we diagnosed the actual status of the 7th National science elective curriculum and suggested a way to select and organize the content of the new science elective curriculum. The first science education reform was grounded in the structuralism where the structure of discipline was valued above everything else. On the other hand, the second science education reform suggested alternative interpretations of students' opportunity to learn, putting a brake on the structuralist thinking. According to the survey result, the majority of the science elective courses are in need for revision because the contents are overcrowded, too difficult in light of students' learning readiness, failed to draw students' interest in science, and are overlapped and repeated among the 10th grade science, high school science I and II. In particular, Earth Science II and physics II are the most unfavorable courses among students. Thus, we recommended a fundamental change be made in the new curriculum in addition to the optimization of the content. In this paper, we suggested 'topic-centered content organization' for the science elective course I, i.e., Physics I, Chemistry I, Biology I and Earth Science I that is designed for both science track and non-science track students. Since curriculum provides students with an 'opportunity to learn', a curriculum study should focus on what the 'opportunity to learn' is that students ought to be offered. Based on the result of this study, we recommended one way to select and organize the content of high school elective curriculum.