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.

BACKGROUND: Previous 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. METHODS: We 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). RESULTS: Before 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. CONCLUSION: Previous 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.

Estimation of breeding value and accuracy using pedigree and genotype of Hanwoo cows (Korean cattle).

The genetic improvement of Hanwoo is dependent on the estimated breeding value (EBV) of pedigree-based Korean proven bull's number, and the genetic evaluation for cows is difficult due to insufficient pedigree and test records. Genomic selection involves utilizing the individual's genotype to estimate the breeding value (BV) and is determined to be an appropriate evaluation method for cows who lack test information. This study used pedigree and genotype to estimate and analyse BV and accuracy of Hanwoo cows in the Gyeongnam area using pedigree best linear unbiased prediction (PBLUP) and genomic best linear unbiased prediction (GBLUP). The test group acquired pedigree and genotype of 919 Hanwoo cows in the Gyeongnam area. The traits used for analysis were carcass weight (CWT), eye muscle areas (EMA), backfat thickness (BFT) and marbling score (MS). PBLUP used Reference group 1 containing the pedigree and phenotype of 919 Hanwoo cows and 545,483 heads to construct the numeric relationship matrix and estimated the EBV and accuracy. GBLUP used Reference group 2 containing the genotype and phenotype of 919 Hanwoo cows and 17,226 heads to construct the genomic relationship matrix and estimated the genomic EBV (GEBV) and accuracy. In the order of CWT, EMA, BFT and MS, the accuracy of PBLUP was 0.488, 0.480, 0.482 and 0.486 while the accuracy of GBLUP was higher with 0.779, 0.758, 0.766 and 0.791. And for 104 cows without relationship coefficient on pedigree to the reference group, the accuracy as PBLUP was estimated to be 0, but for GBLUP, it was possible to estimate the accuracy for all individuals. If GBLUP is applied to cows raised in general farms, the genetic evaluation can be performed even on animals without pedigree and high-accuracy estimation, enabling selection of excellent cows. Accordingly, by securing the genetic diversity of cows, it is expected to increase the profitability of farms by decreasing the inbreeding rate and increasing efficiency of elite calf production.

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.

BACKGROUND: It 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. METHODS: This 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. RESULTS: Of 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). CONCLUSIONS: The 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.

Genetic diversity and population structure of the Sapsaree, a native Korean dog breed.

BACKGROUND: The Sapsaree is a breed of dog (Canis familiaris) native to Korea, which became perilously close to extinction in the mid-1980s. However, with systematic genetic conservation and restoration efforts, this breed was rescued from extinction and population sizes have been gradually increasing over the past few decades. The aim of this study was to ascertain novel information about the genetic diversity, population structure, and demographic history of the Sapsaree breed using genome-wide single nucleotide polymorphism data. We characterized the genetic profile of the Sapsaree breed by comparison with seven foreign dog breeds with similar morphologies to estimate genetic differentiation within and among these breeds. RESULTS: The results suggest that Sapsarees have higher genetic variance compared with the other breeds analyzed. The majority of the Sapsarees in this study share a discrete genetic pattern, although some individuals were slightly different, possibly as a consequence of the recent restoration process. Concordant results from analyses of linkage disequilibrium, effective population size, genetic diversity, and population structural analyses illustrate a relationship among the Sapsaree and the Tibetan breeds Tibetan terrier and Lhasa Apso, and a small genetic introgression from European breeds. The effective population size of the Sapsaree has contracted dramatically over the past generations, and is currently insufficient to maintain long-term viability of the breed's genetic diversity. CONCLUSIONS: This study provides novel insights regarding the genetic diversity and population structure of the native Korean dog breed Sapsaree. Our results suggest the importance of a strategic and systematic approach to ensure the genetic diversity and the authenticity of the Sapsaree breed.

Effect of bilateral upper extremity exercise on trunk performance in patients with stroke.

[Purpose] The aim of this study was to investigate the effect of bilateral upper extremity exercises on trunk performance in patients with stroke. [Subjects and Methods] Twenty in-patients with chronic stroke of at least 6 month's duration participated in this study. Patients in the experimental and control groups received neurological rehabilitation treatment for stroke. In addition to the neurological rehabilitation treatment, patients in the experimental group received 30 minutes of bilateral upper extremity exercises 3 times weekly for 4 weeks. Outcomes were measured using the Trunk Impairment Scale before and after the 4-week training period. [Results] Significant intragroup differences in all items of Trunk Impairment Scale were observed after intervention. In particular, significant intergroup differences were observed for dynamic sitting balance, trunk coordination, and between total scores of the Trunk Impairment Scale. [Conclusion] The results of this study suggest bilateral upper extremity exercises could be used in addition to trunk exercises to improve trunk performance in patients with stroke.

Changes in cardiopulmonary function according to posture during recovery after maximal exercise.

[Purpose] This study was undertaken to measure cardiopulmonary function according to body position during the recovery period after maximal exercise and to identify an effective position after high-intensity exercise. [Subjects and Methods] Fifteen male university students in their twenties participated in the study. The subjects were randomly assigned to the supine position, the sitting position, or the trunk forward leaning position during the recovery period following maximal exercise. Oxygen uptake, minute ventilation volume, respiration rate, and heart rate according to posture were measured in a stable state, at maximal exercise loading, and at 1, 3, and 5 minutes after maximal exercise. [Results] Changes of cardiopulmonary function according to posture during the recovery period after maximal exercise showed that minute ventilation volume was smaller in the trunk forward leaning position than in the sitting or supine positions, and oxygen uptake also declined. [Conclusion] The trunk forward leaning position has a more positive effect on pulmonary ventilation after high-intensity exercise.

Effect of breathing maneuver combined with upper extremity exercise on respiratory capacity in healthy adult men.

[Purpose] This study aimed to determine the effect of the breathing maneuver combined with dynamic motion of the upper limbs on respiratory capacity in healthy adult men. [Subjects and Methods] Twenty-four healthy adult men participated in this study. Subjects were randomly assigned to a control group (n=12) or an experimental group (n=12). The subjects in the control group performed the breathing maneuver without the upper extremity exercise. The subjects in the experimental group performed upper extremity exercise with the breathing maneuver three times a week for 4 weeks. Outcomes were measured using maximum inspiratory and expiratory pressures. [Results] There was a significant difference in maximum inspiratory and expiratory pressures before and after intervention in the experimental group and the control group. In addition, there was a significant difference in maximal expiratory pressure between groups after intervention. [Conclusion] The results of this study suggest the respiration maneuver combined with upper extremity exercise could be used as a program for clinical respiration training.

Effects of electrical stimulation combined with dysphagia therapy in elderly individual with oropharyngeal dysphagia: a case study.

[Purpose] The purpose of the present study was to investigate the effects of dysphagia therapy in an old man with difficulty swallowing in the oral and pharyngeal phases. [Subjects and Methods] The subject was a 72-year-old man with no history of neurological disorders. He was admitted to local hospital because of the complaint of swallowing difficulty. The interventions performed were electrical stimulation and conventional dysphagia therapy. We assessed the tongue and lip muscle strengths. Swallowing function was evaluated by using the videofluoroscopic dysphagia and penetration-aspiration scales. [Results] After the intervention, the tongue and lip muscle strengths increased from 35 to 39 kPa and from 18 to 23 kPa, respectively. Moreover, the oral and pharyngeal phases of the videofluoroscopic dysphagia scale were improved. Furthermore, aspiration decreased from 4 to 2 points in the penetration-aspiration scale. [Conclusion] Our results suggest that electrical stimulation and conventional dysphagia therapy were effective in improving the swallowing function in an elderly individual with dysphagia.

Effect of mirror therapy and electrical stimulation on upper extremity function in stroke with hemiplegic patient: a pilot study.

[Purpose] This study investigated the effects of mirror therapy and neuromuscular electrical stimulation on upper extremity function in stroke patients. [Subjects and Methods] This study recruited 8 stroke patients. All patients were treated with mirror therapy and neuromuscular electrical stimulation five times per week for 4 weeks. Upper limb function evaluation was performed using upper extremity part of fugl meyer assessment. [Results] Before and after intervention, fugl meyer assessment showed significant improvement. [Conclusion] In this study, mirror therapy and neuromuscular electrical stimulation are effective methods for upper extremity function recovery in stroke patients.

Pancreatic volume and endocrine function changes following pancreaticoduodenectomy for peri-ampullary neoplasms: A retrospective single-center study utilizing pancreas volumetry.

Backgrounds/Aims: We evaluated long-term pancreatic functional outcomes, including pancreatic volumetry after pancreaticoduodenectomy (PD) for peri-ampullary neoplasm. Methods: We retrospectively reviewed 353 patients with a 12-month follow-up who underwent elective pancreaticoduodenectomies for peri-ampullary neoplasms at a single university hospital between January 2011 and December 2020. Perioperative and postoperative outcomes, long-term pancreatic endocrine functions, and pancreatic volume changes 12 month postoperatively were evaluated. Results: The mean age was 65.4 years, and the sex ratio was 1.38. The patients with prediagnosed diabetes mellitus (DM) comprised 31.4%. The peri-ampullary neoplasm origins were: the pancreas (49.0%), common bile duct (27.2%), ampulla of Vater (18.4%), and duodenum (5.4%). The 1-week, and 3-, 6-, and 12-month postoperative proportions of patients with DM diagnosed before surgery combined with new-onset postoperative DM were 39.7%, 42.8%, 43.9%, and 49.6%, respectively. The preoperative and postoperative 1-week, and 3-, 6-, and 12-month mean pancreatic volumes were 82.3, 38.7, 28.1, 24.9, and 25.5 mL, respectively. Univariate risk factor analyses for new-onset DM after PD observed no significant difference between the 'No DM after PD' and 'New-onset DM after PD' groups. Conclusions: Following PD for peri-ampullary neoplasms, pancreatic endocrine functions and volumes continued to decrease for a minimum of 12 months. The current study did not identify any causal relationship between pancreatic endocrine dysfunction and pancreatic atrophy following PD.

The Impact of the Multiple Bile Ducts on Postoperative Biliary Complications In Patients Undergoing Living Donor Liver Transplantation.

BACKGROUND: We aimed to investigate the correlation between bile duct number and biliary complications in patients who underwent donor liver transplantation (LDLT). METHODS: We reviewed all patients who underwent LDLT in our hospital between July 2008 and December 2020. The patients were divided into 2 groups according to the number of bile ducts in the living donor graft (single duct [SD] or multiple ducts [MD]). Collected data included donor and recipient demographics, surgical data including bile duct reconstruction, and perioperative and postoperative outcomes. No prisoners were used in this study, and participants were neither coerced nor paid. The current study complies with the Helsinki Congress and the Declaration of Istanbul. RESULTS: All 70 patients were classified as SD (n = 48) and MD (n = 22). Complications related to the bile duct occurred in 27 (38.6%) patients and were more common in the MD group (54.5% vs 31.3%; odds ratio, 2.4). The MD patients had a longer operation time (1052 ± 251 vs 910 ± 215 minutes, P = .019) and a higher percentage of hepaticojejunostomy (31.8% vs 8.3%, P = .012). Donor age, graft-recipient weight ratio, cold ischemic time, and transfusion volume did not differ between groups. Twenty-one patients (77.7%) fully recovered from complications related to the bile duct, but 3 patients (4.3%) had liver graft failure. CONCLUSION: Bile duct-related complications were common in LDLT patients, despite overall good results. Multiple bile ducts may be a potent risk factor for postoperative biliary complications.

Comparison on genomic prediction using pedigree BLUP and single step GBLUP through the Hanwoo full-sib family.

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.

Development of nutrigenomic based precision management model for Hanwoo steers.

Focusing high marble deposition, Hanwoo feedlot system uses high-energy diet over the prolonged fattening period. However, due to the individual genetic variation, around 40% of them are graded into inferior quality grades (QG), despite they utilized the same resources. Therefore, focusing on development of a nutrigenomic based precision management model, this study was to evaluated the response to the divergent selection on genetic merit for marbling score (MS), under different dietary total digestible nutrient (TDN) levels. Total of 111 calves were genotyped and initially grouped according to estimated breeding value (high and low) for marbling score (MS-EBV). Subsequently, managed under two levels of feed TDN%, over the calf period, early, middle, and final fattening periods following 2 × 2 factorial arrangement. Carcasses were evaluated for MS, Back fat thickness (BFT) and Korean beef quality grading standard. As the direct response to the selection was significant, the results confirmed the importance of initial genetic grouping of Hanwoo steers for MS-EBV. However, dietary TDN level did not show an effect (p > 0.05) on the MS. Furthermore, no genetic-by-nutrition interaction for MS (p > 0.05) was also observed. The present results showed no correlation response on BFT (p > 0.05), which indicates that the selection based on MS-EBV can be used to enhance the MS without undesirable effect on BFT. Ultimate turnover of the Hanwoo feedlot operation is primarily determined by the QGs. The present model shows that the initial grouping for MS-EBV increased the proportion of carcasses graded for higher QGs (QG1++ and QG1+) by approximately 20%. Moreover, there appear to be a potential to increase the proportion of QG 1++ animals among the high-genetic group by further increasing the dietary energy content. Overall, this precision management strategy suggests the importance of adopting an MS based initial genetic grouping system for Hanwoo steers with a subsequent divergent management based on dietary energy level.

Comparison of accuracy of breeding value for cow from three methods in Hanwoo (Korean cattle) population.

In Korea, Korea Proven Bulls (KPN) program has been well-developed. Breeding and evaluation of cows are also an essential factor to increase earnings and genetic gain. This study aimed to evaluate the accuracy of cow breeding value by using three methods (pedigree index [PI], pedigree-based best linear unbiased prediction [PBLUP], and genomic-BLUP [GBLUP]). The reference population (n = 16,971) was used to estimate breeding values for 481 females as a test population. The accuracy of GBLUP was 0.63, 0.66, 0.62 and 0.63 for carcass weight (CWT), eye muscle area (EMA), back-fat thickness (BFT), and marbling score (MS), respectively. As for the PBLUP method, accuracy of prediction was 0.43 for CWT, 0.45 for EMA, 0.43 for MS, and 0.44 for BFT. Accuracy of PI method was the lowest (0.28 to 0.29 for carcass traits). The increase by approximate 20% in accuracy of GBLUP method than other methods could be because genomic information may explain Mendelian sampling error that pedigree information cannot detect. Bias can cause reducing accuracy of estimated breeding value (EBV) for selected animals. Regression coefficient between true breeding value (TBV) and GBLUP EBV, PBLUP EBV, and PI EBV were 0.78, 0.625, and 0.35, respectively for CWT. This showed that genomic EBV (GEBV) is less biased than PBLUP and PI EBV in this study. In addition, number of effective chromosome segments (Me) statistic that indicates the independent loci is one of the important factors affecting the accuracy of BLUP. The correlation between Me and the accuracy of GBLUP is related to the genetic relationship between reference and test population. The correlations between Me and accuracy were -0.74 in CWT, -0.75 in EMA, -0.73 in MS, and -0.75 in BF, which were strongly negative. These results proved that the estimation of genetic ability using genomic data is the most effective, and the smaller the Me, the higher the accuracy of EBV.

Multi-biomarker panel prediction model for diagnosis of pancreatic cancer.

BACKGROUND/PURPOSE: The current study aimed to develop a prediction model using a multi-marker panel as a diagnostic screening tool for pancreatic ductal adenocarcinoma. METHODS: Multi-center cohort of 1991 blood samples were collected from January 2011 to September 2019, of which 609 were normal, 145 were other cancer (colorectal, thyroid, and breast cancer), 314 were pancreatic benign disease, and 923 were pancreatic ductal adenocarcinoma. The automated multi-biomarker Enzyme-Linked Immunosorbent Assay kit was developed using three potential biomarkers: LRG1, TTR, and CA 19-9. Using a logistic regression model on a training data set, the predicted values for pancreatic ductal adenocarcinoma were obtained, and the result was classification into one of the three risk groups: low, intermediate, and high. The five covariates used to create the model were sex, age, and three biomarkers. RESULTS: Participants were categorized into four groups as normal (n = 609), other cancer (n = 145), pancreatic benign disease (n = 314), and pancreatic ductal adenocarcinoma (n = 923). The normal, other cancer, and pancreatic benign disease groups were clubbed into the non-pancreatic ductal adenocarcinoma group (n = 1068). The positive and negative predictive value, sensitivity, and specificity were 94.12, 90.40, 93.81, and 90.86, respectively. CONCLUSIONS: This study demonstrates a significant diagnostic performance of the multi-marker panel in distinguishing pancreatic ductal adenocarcinoma from normal and benign pancreatic disease states, as well as patients with other cancers.

Automated pancreas segmentation and volumetry using deep neural network on computed tomography.

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.

Long-term artificial selection of Hanwoo (Korean) cattle left genetic signatures for the breeding traits and has altered the genomic structure.

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 (piHS > 6) or negative (piHS < -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.