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A Study on Predictive Modeling of I-131 Radioactivity Based on Machine Learning
유연욱(Yeon-Wook You),이충운(Chung-Wun Lee),김정수(Jung-Soo Kim) 대한방사선과학회(구 대한방사선기술학회) 2023 방사선기술과학 Vol.46 No.2
High-dose I-131 used for the treatment of thyroid cancer causes localized exposure among radiology technologists handling it. There is a delay between the calibration date and when the dose of I-131 is administered to a patient. Therefore, it is necessary to directly measure the radioactivity of the administered dose using a dose calibrator. In this study, we attempted to apply machine learning modeling to measured external dose rates from shielded I-131 in order to predict their radioactivity. External dose rates were measured at 1 m, 0.3 m, and 0.1 m distances from a shielded container with the I-131, with a total of 868 sets of measurements taken. For the modeling process, we utilized the hold-out method to partition the data with a 7:3 ratio (609 for the training set:259 for the test set). For the machine learning algorithms, we chose linear regression, decision tree, random forest and XGBoost. To evaluate the models, we calculated root mean square error (RMSE), mean square error (MSE), and mean absolute error (MAE) to evaluate accuracy and R2 to evaluate explanatory power. Evaluation results are as follows. Linear regression (RMSE 268.15, MSE 71901.87, MAE 231.68, R2 0.92), decision tree (RMSE 108.89, MSE 11856.92, MAE 19.24, R2 0.99), random forest (RMSE 8.89, MSE 79.10, MAE 6.55, R2 0.99), XGBoost (RMSE 10.21, MSE 104.22, MAE 7.68, R2 0.99). The random forest model achieved the highest predictive ability. Improving the model’s performance in the future is expected to contribute to lowering exposure among radiology technologists.
You, Jae-Sung,Park, Mi-Na,Song, Wook,Lee, Yeon-Sook Canadian Science Publishing 2010 APPLIED PHYSIOLOGY NUTRITION AND METABOLISM Vol.35 No.3
<P> Reduced muscle activity leads to impaired insulin signaling, which leads to loss of contractile proteins and muscle mass via the Akt pathway. Dietary fish oil rich in long chain n-3 polyunsaturated fatty acids has been shown to prevent insulin signaling resistance in skeletal muscle. This study was conducted to elucidate the protective effect of dietary fish oil on disuse-induced perturbations in insulin signaling and soleus muscle atrophy. To accomplish this, rats were fed a corn-oil- (control) or fish-oil-based diet for 2 weeks, and then subjected to hindlimb immobilization while still receiving the same diets. After 10 days of immobilization, the soleus muscle mass and myosin heavy chain level had markedly decreased; however, these losses were significantly suppressed in rats fed dietary fish oil, compared with the control group. Dietary fish oil nearly completely attenuated the disturbances in activation of the Akt and p70 S6 kinase proteins, as well as the gene expression of muscle-specific E3 ubiquitin ligases (muscle atrophy F-box and muscle RING finger 1). However, insulin receptor substrate 1 associated with the p85 subunit of phosphoinositide 3-kinase was not altered during immobilization. Dietary fish oil also inhibited alterations in the gene expression of cyclooxygenase-2 and inducible nitric oxide synthase, with no additional observation of oxidative stress. Collectively, these findings indicate that dietary fish oil prior to and during immobilization may alleviate the immobilization-induced soleus muscle atrophy, at least in part, via the Akt pathway through E3 ubiquitin ligases and p70s6k. </P>
( Yeon Wook Kim ),( Nakwon Kwak ),( Moon Woo Seong ),( Eui Chong Kim ),( Chul Gyu You ),( Young Whan Kim ),( Sung Koo Han ),( Jae Joon Yim ) 대한결핵 및 호흡기학회 2014 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.118 No.-
Background: The Xpert MTB/RIF assay is endorsed by the WHO for detecting pulmonary and extrapulmonary tuberculosis (EPTB). The aim of this study was to determine the accuracy of the Xpert MTB/RIF assay in diagnosing EPTB in South Korea, which has an intermediate TB burden. Methods: We retrospectively reviewed the medical records of 1,426 patients in whom the Xpert MTB/RIF assay using extrapulmonary specimens was requested between January 1, 2011 and October 31, 2013 in a tertiary referral hospital in South Korea. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for diagnosis of EPTB and detection of rifampicin resistance were calculated. Results: Using culture as gold standard, sensitivity, specificity, PPV, and NPV of the assay were 67.7%, 98.1%, 60%, and 98.6%, respectively. Higher sensitivity was shown among specimens including needle aspirates and biopsied tissues (85.7%), pus (75%), joint fluids (100%), and urine (100%). The sensitivity, specificity, PPV, and NPV for the detection of rifampicin resistance among specimens with positive results for M. TB were 80%, 100%, 100%, and 97.7%, respectively. Conclusions: The Xpert MTB/RIF assay showed acceptable sensitivity and excellent specificity for diagnosis of EPTB and detection of rifampicin resistance in a country with an intermediate TB burden.
Genome-wide microRNA expression profiling in fetal trisomy 21 placenta
( You Jung Shin ),( Ji Hyae Lim ),( So Yeon Park ),( Da Eun Lee ),( Hyun Kyong Ahn ),( Si Won Lee ),( June Seek Choi ),( Dong Wook Kwak ),( Jin Hoon Chung ),( Hyun Mee Ryu ) 대한산부인과학회 2014 대한산부인과학회 학술대회 Vol.100 No.-
목적: Differential expression of microRNAs (miRNAs) has been identified in many diseases, including trisomy 21 (T21). However, the changes of the genome-wide miRNAs expression in the T21 placenta have yet to be determined. Moreover, the biological functions of the differentially expressed miRNAs in the T21 placenta are still unclear. Thus, we investigated the genome-wide miRNAs expression profiling of the T21 placenta using microarray and analyzed their biological functions using bioinformatics tools. 방법: Total RNA extracted from placenta samples of T21 and euploid fetus was hybridized onto human miRNA microarray and expression data were analyzed on R statistical environment. To investigate the functions of the differentially expressed miRNAs (fold change>2.0 and p<0.05), the miRWalk database was used to predict their potential targets, which were afterwards submitted to the functional annotation tool provided by the WebGestalt database. 결과: In total, 34 miRNAs were significantly differentially expressed in the T21 placenta (16 up-regulated and 18 down-regulated). However, chromosome 21-derived miRNAs were not detected. In analysis of genes predicted to be targeted by the differentially expressed miRNAs, target genes of up-regulated and down-regulated miRNAs were identified 7,434 and 6,071, respectively. Out of total target genes, 76 genes were identified within chromosome 21 and were potentially regulated by the differentially expressed miRNAs in the T21 placenta (10 and 34 genes being controlled by the down- and up-regulated miRNAs, respectively, and 32 by both). Functional annotation analyses revealed that target genes of abnormally expressed miRNAs were significantly associated with in T21 as well as T21-related disorder such as mental retardation, neurobehavioral manifestations, congenital abnormalities, and so on. 결론: Our results provide a new insight into understanding the expression characteristic of miRNAs in the T21 fetal placenta. Additionally, findings of our study indicate that the differentially expressed miRNAs in the T21 placenta may potentially affect various pathways related with pathogenesis of the T21.
Yeon-Sook Lee,Eun-Young Kang,Mi-Na Park,You-Young Choi,Jeong-Wook Jeon,Sung-Seob Yun 한국영양학회 2008 Nutrition Research and Practice Vol.2 No.1
This study was carried out to investigate the efficacy of sn-2 palmitic acid-fortified vegetable oil (Sn2PA) on calcium absorption and to confirm the synergistic effects of fructooligosaccharide on calcium absorption. Male SD rats were fed 6 kinds of casein based diets containing vegetable oil (control), sn-2 palmitic acid-fortified vegetable oil (Sn2PA) and Sn2PA with fructooligosaccharide(Sn2PAFO) in two levels of calcium (normal 0.5% and high 1.0%) for 3 weeks. Total lipids, cholesterol, triglyceride and calcium in blood were measured. Feces were collected using cages for 4 days. Serum concentrations of total lipids and calcium were not significantly different among groups. However, serum triglyceride was significantly decreased by fructooligosaccharide supplementation regardless of dietary calcium level. The lipid absorption was not significantly different among experimental groups. Calcium absorption was significantly higher in Sn2PAFO group than other groups. Calcium solubility of intestine was increased by sn-2 palmitic acid supplementation. These results suggest that sn-2 palmitic acid and fructooligosaccharide supplementation could be beneficial for baby foods including infant formula, with regard to increasing absorption of calcium by more soluble calcium in the small intestinal content.
( Yeon Wook Kim ),( Na Kwon Kwak ),( Moon Woo Seong ),( Eui Chong Kim ),( Chul Gyu You ),( Young Whan Kim ),( Sung Koo Han ),( Jae Joon Yim ) 대한내과학회 2014 대한내과학회 추계학술발표논문집 Vol.2014 No.1
Background: The Xpert MTB/RIF assay is endorsed by the WHO for detecting pulmonary and extrapulmonary tuberculosis (EPTB). The aim of this study was to determine the accuracy of the Xpert MTB/RIF assay in diagnosing EPTB in South Korea, which has an intermediate TB burden. Methods: We retrospectively reviewed the medical records of 1,426 patients in whom the Xpert MTB/RIF assay using extrapulmonary specimens was requested between January 1, 2011 and October 31, 2013 in a tertiary referral hospital in South Korea. The sensitivity, specifi city, positive predictive value (PPV) and negative predictive value (NPV) for diagnosis of EPTB and detection of rifampicin resistance were calculated. Results: Using culture as gold standard, sensitivity, specifi city, PPV, and NPV of the assay were 67.7%, 98.1%, 60%, and 98.6%, respectively. Higher sensitivity was shown among specimens including needle aspirates and biopsied tissues (85.7%), pus (75%), joint fi uids (100%), and urine (100%). The sensitivity, specifi city, PPV, and NPV for the detection of rifampicin resistance among specimens with positive results for M. TB were 80%, 100%, 100%, and 97.7%, respectively. Conclusions: The Xpert MTB/RIF assay showed acceptable sensitivity and excellent specifi city for diagnosis of EPTB and detection of rifampicin resistance in a country with an intermediate TB burden.
Therapeutic efficacy of oral cyclosporine in female pattern hair loss
( You Jin Jung ),( Se Uk Oh ),( Chang Hwa Song ),( Young Wook Ko ),( Jeong Eun Kim ),( Joo Yeon Ko ),( Young Suck Ro ) 대한피부과학회 2020 대한피부과학회 학술발표대회집 Vol.72 No.1
Background: Female pattern hair loss (FPHL) is the most common type of androgenetic alopecia in women. It is characterized by a diffuse thinning of the centroparietal area with maintenance of the frontal hair line. The exact mechanism of FPHL has not yet been understood, and standardized treatment protocol has not yet been established. Objectives: The aim of this study was to evaluate the effectiveness of combination therapy in female patients with FPHL using oral cyclosporine with pantothenic acid complex-based dietary supplement (treated group) compared to pantothenic acid complex-based dietary supplement monotherapy (control group). Methods: A total of 25 patients with FPHL were in treated group and 31 patients were in control group. The therapeutic efficacy in both groups was retrospectively evaluated using Ludwig scale. Results: The average patient age was 46.96 in treated group and 44.83 in control group. The average drug administration period was 19.57 months in treated group and 11.37 months in control group. Proportion of improvement from the base was 84% and 51.6% respectively. Average Ludwig score changed from 1.88 to 1.08 in treated group, and from 1.32 to 0.83 in control group. Average Ludwig score change was 0.8 and 0.49 respectively, indicating that the treated group showed more dominant treatment effect (p<0.02). Conclusion: Cyclosporine could be a treatment option for intractable FPHL, because of its hypertrichosis effect.