Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
578
result(s) for
"Lee, Doo Ho"
Sort by:
Automated pancreas segmentation and volumetry using deep neural network on computed tomography
2022
Pancreas segmentation is necessary for observing lesions, analyzing anatomical structures, and predicting patient prognosis. Therefore, various studies have designed segmentation models based on convolutional neural networks for pancreas segmentation. However, the deep learning approach is limited by a lack of data, and studies conducted on a large computed tomography dataset are scarce. Therefore, this study aims to perform deep-learning-based semantic segmentation on 1006 participants and evaluate the automatic segmentation performance of the pancreas via four individual three-dimensional segmentation networks. In this study, we performed internal validation with 1,006 patients and external validation using the cancer imaging archive pancreas dataset. We obtained mean precision, recall, and dice similarity coefficients of 0.869, 0.842, and 0.842, respectively, for internal validation via a relevant approach among the four deep learning networks. Using the external dataset, the deep learning network achieved mean precision, recall, and dice similarity coefficients of 0.779, 0.749, and 0.735, respectively. We expect that generalized deep-learning-based systems can assist clinical decisions by providing accurate pancreatic segmentation and quantitative information of the pancreas for abdominal computed tomography.
Journal Article
Central Pancreatectomy Versus Distal Pancreatectomy and Pancreaticoduodenectomy for Benign and Low-Grade Malignant Neoplasms: A Retrospective and Propensity Score-Matched Study with Long-Term Functional Outcomes and Pancreas Volumetry
2020
BackgroundIt remains controversial whether central pancreatectomy (CP) can preserve the exocrine and endocrine function of the pancreas or not. This study aimed to evaluate the safety and efficacy of CP compared with distal pancreatectomy (DP) and pancreaticoduodenectomy (PD) for benign and low-grade malignant neoplasms.MethodsThis retrospective study enrolled 219 patients who underwent elective CP (n = 55), DP (n = 70), or PD (n = 94) for benign and low-malignant neoplasms in a single university hospital between January 2000 and December 2015. Patients who underwent CP were propensity score matched to patients who underwent DP or PD at a 1:1 ratio, respectively. Peri- and postoperative outcomes, long-term endocrine/exocrine function, and pancreatic volume change 12 months postoperatively were prospectively evaluated.ResultsOf the 165 patients, 55 were included in each of the CP, DP, and PD groups. Significant differences between the CP and DP groups were observed in overall morbidity (CP: n = 18, 33% vs DP: n = 8, 14%; P = 0.041), clinically relevant postoperative pancreatic fistula (CP: n = 13, 24% vs DP: n = 4, 7%; P = 0.022), stool elastase level 12 months after surgery (CP: 151 μg/g vs DP: 245 μg/g; P = 0.003), and percentage change in the remnant pancreatic volume 12 months after surgery (CP: − 9.4% vs DP: + 7.5%; P < 0.001).ConclusionsThe indications for CP to treat benign and low-grade malignant pancreatic neoplasms should be limited to cases in which the distal pancreatic volume can be considerably saved and PD can be prevented because CP has a higher postoperative morbidity without a marked functional superiority over DP.
Journal Article
Laparoscopic cholecystectomy in patients with previous upper midline abdominal surgery: comparison of laparoscopic cholecystectomy after gastric surgery and non-gastric surgery using propensity score matching
2022
BackgroundPrevious upper midline abdominal surgery is a reported relative contraindication to laparoscopic cholecystectomy. We aimed to investigate the effects of previous upper abdominal surgery on the feasibility and safety of laparoscopic cholecystectomy; we evaluated the effects of the previous upper abdominal surgery type on laparoscopic cholecystectomy with respect to complications and conversion to open surgery.MethodsWe prospectively evaluated 1,258 patients who underwent laparoscopic cholecystectomy, including those who underwent upper midline abdominal surgery previously, at a single tertiary referral center. The perioperative and postoperative outcomes—open conversion rate, operation time, intraoperative and postoperative complications, and length of hospital stay—were evaluated. Patients were grouped according to the previous surgical method into the gastric (n = 77), non-gastric (n = 40), and control (n = 1141) groups. Patients in the gastric + non-gastric groups (n = 117) were 1:1 matched with those in the control group (n = 117) using propensity score matching (PSM).ResultsBefore PSM, age, sex, open conversion rate, gallbladder status, port number, overall morbidity, and postoperative hospital stay duration did not significantly differ between the gastric and non-gastric groups; the body mass index (22.3 ± 3.4 versus 24.1 ± 3.8 kg/m2, p = 0.009) and operation time (129.9 ± 63.6 versus 97.9 ± 51.1 min, p = 0.004) significantly differed. After PSM, age, sex, body mass index, and American Society of Anesthesiology score did not significantly differ between gastric + non-gastric (n = 117) and conventional groups (n = 117; the operation time (118.9 ± 61.3 versus 75.8 ± 37.1 min, p < 0.001), open conversion rate (n = 6, 5.1% versus n = 0, 0.0%, p = 0.013), port number, overall morbidities (n = 26, 22.2% versus n = 10, 8.5%, p = 0.004), and postoperative hospital stay duration (6.7 ± 4.3 versus 5.5 ± 3.2 days, p = 0.031) significantly differed.ConclusionPrevious upper midline abdominal surgery was not contraindicative to safe laparoscopic cholecystectomy. Patients with previous upper midline abdominal surgery undergoing laparoscopic cholecystectomy should be informed preoperatively of the probability of conversion to open surgery, lengthened duration, and associated morbidities.
Journal Article
Long-term artificial selection of Hanwoo (Korean) cattle left genetic signatures for the breeding traits and has altered the genomic structure
2022
Indigenous Korean breeds such as Hanwoo (Korean) cattle have adapted to their local environment during the past 5000 years. In the 1980s, the National Genetic Improvement Program was established to develop a modern economic breed for beef production in Korea through artificial selection. This process is thought to have altered the genomic structure of breeding traits over time. The detection of genetic variants under selection could help to elucidate the genetic mechanism of artificial selection in modern cattle breeds. Indigenous Hanwoo cattle have adapted in response to local natural and artificial selection during a 40-year breeding program. We analyzed genomic changes in the selection signatures of an unselected population (USP; n = 362) and a selected population (KPN; n = 667) of Hanwoo cattle. Genomic changes due to long-term artificial selection were identified using a genome-wide integrated haplotype score (iHS) and a genome-wide association study (GWAS). Signatures of recent selection were detected as positive (
p
iHS > 6) or negative (
p
iHS < –6) iHS scores spanning more than 46 related genes in KPN cattle, but none in USP cattle. A region adjacent to the
PLAG1
gene was found to be under strong selection for carcass weight. The GWAS results also showed a selection signature on BTA14, but none on BTA13. Pathway and quantitative trait locus analysis results identified candidate genes related to energy metabolism, feed efficiency, and reproductive traits in Hanwoo cattle. Strong selection significantly altered Hanwoo cattle genome structural properties such as linkage disequilibrium (LD) and haplotypes through causal mutation for target traits. Haplotype changes of genome structure which are changes of ancestral allele to derived alleles due to selection were clearly identified on BTA13 and BTA14; however, the structure of the LD block was not clearly observed except BTA14. Thus, selection based on EBVs would be working very well in Hanwoo cattle breeding program appears to have been highly successful.
Journal Article
ASO Author Reflections: Central Pancreatectomy Versus Distal Pancreatectomy and Pancreaticoduodenectomy for Benign or Low-Grade Malignant Neoplasms: A Propensity Score-Matched Study with Long-Term Functional Outcomes and Pancreas Volumetry
2020
Background:The optimal radioactive tracer and technique for sentinel lymph node localization in breast cancer is yet to be determined. The dilemma of small particle size with dispersion to second echelon nodes versus failure of migration of larger radiocolloids needs to be resolved. A new radiocolloid preparation with particle size under 0.1 micron was developed with excellent primary/post lymphatic entrapment ratio. Objective:To assess the feasibility of a new 99mTc radiocolloid cysteine-rhenium colloid in sentinel lymph node (SLN) localization for breast cancer. Methods:Forty-seven patients with newly diagnosed T1 or T2 breast cancer underwent injection of 99mTc-labeled cysteine-rhenium colloid followed by lymphoscintigraphy. Same day SLN biopsy with patent blue dye and intraoperative gamma probe to identify SLNs were performed. Results:SLN mapping and intraoperative localization were successful in 46/47 (98%) of patients. The blue dye radioactive tracer concordance was 94%. There was one false-negative in a patient with a nonpalpable tumor that underwent ultrasound-guided peritumoral radiocolloid injection. Conclusions:99mTc-cysteine-rhenium colloid is highly effective in identifying SLNs. It has the advantage of smaller particle size than sulfur colloid with easier lymphatic migration. It has a more neutral pH with less pain on injection and does not require filtration, thereby minimizing radiation exposure to technologists.
Journal Article
Decisions on Pricing, Sustainability Effort, and Carbon Cap under Wholesale Price and Cost-Sharing Contracts
2022
Rapid economic growth and industrialization have brought material abundance and convenience, but also social and environmental problems such as global warming, climate change, and ozone depletion. For this reason, the public and governments have continued to make efforts to reduce carbon oxide emissions worldwide over the past few decades. To achieve this mission, cap-and-trade regulations have been introduced as one of the most effective market-based mechanisms to control carbon emissions. Accordingly, sustainability efforts, including the development of green products and innovating manufacturing technologies, are being made by companies in supply chains to reduce their carbon emissions. In the context of sustainability innovations and carbon emission constraints, this article investigates pricing decisions, the degree of sustainability efforts, and carbon caps under two different supply chain contracts—in this case, wholesale price contract and cost-sharing contract. This article establishes a Stackelberg game model under each of the supply chain contract types and presents the equilibrium decisions made by players of the game. Major findings of this article reveal that (i) the performance of the supply chain is considerably affected by the presence of a carbon cap; (ii) the higher the carbon cap set by a government is, the more sustainability innovation efforts the supply chain makes; and (iii) the supply chain can improve its profitability and its sustainability under a cost-sharing contract.
Journal Article
Deep Learning Model for Volume Measurement of the Remnant Pancreas After Pancreaticoduodenectomy and Distal Pancreatectomy
by
Yang, Jaehun
,
Lee, Doo-Ho
,
Kim, Doojin
in
Abdomen
,
Artificial intelligence
,
Clinical medicine
2025
Background/Objectives: Accurate volumetry of the remnant pancreas after pancreatectomy is crucial for assessing postoperative endocrine and exocrine function but remains challenging due to anatomical variability and complex postoperative morphology. This study aimed to develop and validate a deep learning (DL)-based model for automatic segmentation and volumetry of the remnant pancreas using abdominal CT images. Methods: A total of 1067 CT scans from 341 patients who underwent pancreaticoduodenectomy and 512 scans from 184 patients who underwent distal pancreatectomy were analyzed. Ground truth masks were manually delineated and verified through multi-expert consensus. Six 3D segmentation models were trained and compared, including four convolution-based U-Net variants (basic, dense, residual, and residual dense) and two transformer-based models (Trans U-Net and Swin U-Net). Model performance was evaluated using five-fold cross-validation with sensitivity, specificity, precision, accuracy, and Dice similarity coefficient. Results: The Residual Dense U-Net achieved the best performance among convolutional models, with dice similarity coefficient (DSC) values of 0.7655 ± 0.0052 for pancreaticoduodenectomy and 0.8086 ± 0.0091 for distal pancreatectomy. Transformer-based models showed slightly higher DSCs (Swin U-Net: 0.7787 ± 0.0062 and 0.8132 ± 0.0101), with statistically significant but numerically small improvements (p < 0.01). Conclusions: The proposed DL-based approach enables accurate and reproducible postoperative pancreas segmentation and volumetry. Automated volumetric assessment may support objective evaluation of remnant pancreatic function and provide a foundation for predictive modeling in long-term clinical management after pancreatectomy.
Journal Article
Comparison on genomic prediction using pedigree BLUP and single step GBLUP through the Hanwoo full-sib family
2023
Objective: When evaluating individuals with the same parent and no phenotype by pedigree best linear unbiased prediction (BLUP), it is difficult to explain carcass grade difference and select individuals because they have the same value in pedigree BLUP (PBLUP). However, single step GBLUP (ssGBLUP), which can estimate the breeding value suitable for the individual by adding genotype, is more accurate than the existing method.Methods: The breeding value and accuracy were estimated with pedigree BLUP and ssGBLUP using pedigree and genotype of 408 Hanwoo cattle from 16 families with the same parent among siblings produced by fertilized egg transplantation. A total of 14,225 Hanwoo cattle with pedigree, genotype and phenotype were used as the reference population. PBLUP obtained estimated breeding value (EBV) using the pedigree of the test and reference populations, and ssGBLUP obtained genomic EBV (GEBV) after constructing and H-matrix by integrating the pedigree and genotype of the test and reference populations.Results: For all traits, the accuracy of GEBV using ssGBLUP is 0.18 to 0.20 higher than the accuracy of EBV obtained with PBLUP. Comparison of EBV and GEBV of individuals without phenotype, since the value of EBV is estimated based on expected values of alleles passed down from common ancestors. It does not take Mendelian sampling into consideration, so the EBV of all individuals within the same family is estimated to be the same value. However, GEBV makes estimating true kinship coefficient based on different genotypes of individuals possible, so GEBV that corresponds to each individual is estimated rather than a uniform GEBV for each individual.Conclusion: Since Hanwoo cows bred through embryo transfer have a high possibility of having the same parent, if ssGBLUP after adding genotype is used, estimating true kinship coefficient corresponding to each individual becomes possible, allowing for more accurate estimation of breeding value.
Journal Article
Decision Making in a Closed-Loop Supply Chain with a Waste Management Program: Manufacturers’ Take-Back Activity and Governmental Subsidies for Remanufacturing
2023
As awareness of climate change increases, diverse initiatives such as subsidies for remanufactured products and take-back programs for end-of-life products have been taken to conserve energies and materials. This paper explores how the subsidy program affects manufacturer’s take-back activity in a closed-loop supply chain and also analyzes how a coalition between a retailer and a remanufacturer affects the equilibrium decisions. Major findings of this paper reveal that (i) when a take-back program is implemented, the government imposes a high penalty on products that are not collected, thereby encouraging manufacturers to collect more used products, (ii) implementing a take-back program in conjunction with a subsidy program results in a greater reduction in environmentally negative impacts and an enhanced social welfare compared to implementing them separately, and (iii) a coalition between a retailer and a remanufacturer results in lowering the penalty imposed to a manufacturer, which leads to lowering the quantity of the collected and remanufactured products.
Journal Article
Evaluation of imputation performance based on the single nucleotide polymorphism panel density and the reference population size in Korean native chicken
2025
Objective: This study aimed to identify the optimal single nucleotide polymorphism (SNP) panel density for accurate imputation in the Korean native chicken (KNC) and Yeonsan Ogye (YO) populations. The primary focus was on evaluating how the reference population size and SNP density influence imputation performance and accuracy.Methods: Data were collected from five purebred lines of KNC and the YO population, comprising a total of 256 KNC and 199 YO chickens. Imputed genotype ratio and accuracy were evaluated across various scenarios using SNP densities of 2.5K, 5K, 10K, and 50K in both populations. Additionally, for the YO dataset, reference population sizes of 50, 100, and 150 were analyzed to assess their impact on imputation outcomes.Results: Higher SNP densities notably improved imputation performance. Specifically, when SNP panel density reached 10K or greater, the ratio of imputed SNPs exceeded 70% and the accuracy increased substantially, regardless of the reference population size. However, imputation efficiency decreased markedly when either the reference or test population size was around 50 individuals.Conclusion: A test SNP density of at least 10K was determined to be essential for accurate genotype imputation. Additionally, imputation efficiency was observed to decline when either the reference or test population included around 50 individuals. These findings provide important data that can guide the genetic improvement of indigenous livestock populations.
Journal Article