1.Field investigation of bovine leukemia virus: env-based PCR detection and hematologic predictors in Korean dairy herds with productivity issues
Woojae CHOI ; Jiyeon KIM ; Eunhui CHOE ; Danil KIM ; Younghye RO
Journal of Veterinary Science 2026;27(3):e32-
Objective:
To investigate prevalence of BLV and its association with hematological alterations in targeted dairy farms experiencing productivity issues in Korea.
Methods:
This study investigated five dairy farms reporting decreased milk yield, recurrent mastitis, poor conception rates, and delayed postpartum recovery. Eighty lactating cows underwent physical examination, body condition scoring, hematological and biochemical analyses, and polymerase chain reaction testing for BLV.
Results:
Overall BLV detection rate among these herds was 70% (56/80), with intra-herd positivity ranging from 57.1 to 90.0%. Lymphocytosis was observed in 31% of the cows.Multivariable generalized estimating equations analysis confirmed that higher lymphocyte counts were the strongest independent predictor of BLV status (adjusted odds ratio, 2.70;p = 0.005), demonstrating a robust association between hematological alterations and BLV positivity.
Conclusions
and Relevance: BLV infection is highly prevalent in the investigated Korean dairy farms with productivity problems. While these results may not represent the nationwide average due to selection bias, they emphasize the need for nationwide BLV surveillance and implementation of control measures in Korea.
2.Remission of diabetes with glutamic acid decarboxylase antibody positivity that developed after the administration of olanzapine: a case report
Kyuho KIM ; Soo Hyun SEO ; Yun Ji HONG ; Woojae MYUNG ; Bomi KIM ; Chang Ho AHN ; Sung Hee CHOI ; Hak Chul JANG ; Tae Jung OH
Precision and Future Medicine 2026;10(1):51-56
Olanzapine is a second-generation antipsychotic drug associated with the development of type 2 diabetes. However, the development and remission of diabetes with glutamic acid decarboxylase (GAD) antibody (Ab) positivity related to olanzapine treatment have not been reported. Here, we present the case of a 33-year-old man taking olanzapine who was diagnosed with diabetes with GAD Ab positivity complicated by diabetic ketoacidosis (DKA). After discontinuation of the drug and tight glycemic control, his diabetes remitted, and the GAD Ab became negative spontaneously after 18 months. The classification of diabetes is challenging because of overlapping autoimmune and metabolic features. Olanzapine may have contributed to pancreatic β-cell apoptosis, which could potentially trigger autoimmunity and the development of type 1 diabetes-like features (DKA as the initial presentation, a low C-peptide level, and GAD Ab positivity). The rapid amelioration of hyperglycemia and weight reduction may be responsible for the remission of diabetes after the discontinuation of olanzapine.
3.Polyunsaturated Fatty Acids and Skin Cancer: Two-Sample Mendelian Randomization Study
Gahyun KIM ; Bo Ri KIM ; Kyungho PAIK ; Seon-Pil JIN ; Hyunsun PARK ; Woojae MYUNG ; Jin-Ku LEE ; Chong Won CHOI ; Jinho KIM
Annals of Dermatology 2025;37(6):363-376
Background:
Observational studies have suggested associations between dietary polyunsaturated fatty acids (PUFAs) and cancer risk; however, causal inference regarding skin cancer remains limited due to potential recall bias, confounding, and reverse causation.
Objective:
This study aimed to evaluate the causal association between genetically predicted circulating PUFA levels and the risk of skin cancers, including basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and melanoma.
Methods:
We conducted a 2-sample Mendelian randomization (MR) study using genome-wide association study summary statistics from the UK Biobank (PUFAs, n=115,006) and the FinnGen consortium (BCC, n=26,272; SCC, n=4,663; melanoma, n=5,753). Genetic instruments were derived for omega-3, docosahexaenoic acid, omega-6, linoleic acid, and the omega-6:3 ratio.Multiple MR methods—including inverse-variance weighted, MR-Egger, weighted median, weighted mode, and MR-PRESSO—were applied to test for consistency and assess pleiotropy and heterogeneity.
Results:
A higher genetically predicted linoleic acid to total fatty acid ratio was associated with a significantly lower risk of BCC and SCC. Conversely, higher genetically proxied serum omega-3 levels were associated with increased risks of BCC, SCC, and melanoma. The risk effect on SCC was attenuated upon exclusion of rs174528, a variant in the fatty acid desaturase 1 (FADS1) gene, suggesting a role for endogenous PUFA metabolism in carcinogenesis.
Conclusion
This MR analysis supports a causal role of circulating PUFAs in skin cancer development and highlights the importance of FADS-mediated endogenous PUFA metabolism. These findings provide novel insights into the genetic and metabolic underpinnings of skin cancer susceptibility.
4.Comparisons of Genetic Architecture Using Polygenic Risk Scores Derived From Large-Scale Genome-Wide Association Study Data Between Patients With Schizophrenia, Bipolar Disorder and Healthy Controls
Dong Eun LEE ; Min Jun CHOI ; Eun Young CHO ; Yong Min AHN ; Hyunju LEE ; Woojae MYUNG ; Tae Hyon HA ; Sung-Wan KIM ; Heon-Jeong LEE ; Kyooseob HA ; Kyung Sue HONG ; Ji Hyun BAEK
Korean Journal of Schizophrenia Research 2024;27(2):57-62
Objectives:
In this study, we aimed to compare the genetic architecture of schizophrenia (SCZ) and bipolar disorder (BD) in a Korean population by analyzing polygenic risk scores (PRS) derived from large-scale psychiatric disorder genome-wide association study data, based on genetic information collected from SCZ, BD, and healthy control groups.
Methods:
The study included 713 Korean patients with SCZ, 1,317 with BD, 526 healthy controls. Genotyping was performed using the Korean Biobank Array. PRS-continuous shrinkage method was used to calculate the PRS. Analysis of covariance (ANCOVA) was conducted to determine the association between SCZ or BD disorder and PRS after adjusting for sex.
Results:
ANCOVA revealed significant differences in PRS values by diagnosis for PRS for SCZ (F=215.281, p<0.001), PRS for BD (F=13.811, p<0.001), and PRS for major depressive disorder (F=6.042, p=0.002). Post-hoc analysis showed that PRS for SCZ was highest in SCZ, followed by BD, and healthy controls. PRS for BD was elevated in both BD and SCZ compared to healthy controls.
Conclusion
Our study revealed quantitative differences in genetic architecture between SCZ and BD compared to healthy controls, while also suggesting a shared genetic background between the two disorders.
5.Application of tenotomy on Korean native cattle (Hanwoo) with spastic paresis symptoms in the field
Younghye RO ; Woojae CHOI ; Leegon HONG ; Kyunghyun MIN ; Inkwang RYU ; Danil KIM
Journal of Veterinary Science 2023;24(3):e45-
Bovine spastic paresis (BSP) is a neuromuscular disorder characterized by hypertension and stiffness of hindlimb. Two Korean native cattle (Hanwoo) calves developed BSP or BSP-like symptoms, and a tenotomy of superficial tendon of medial head and deep tendon of lateral head of gastrocnemius muscle was performed for treatment. A cast was applied postoperatively to prevent muscle rupture and was removed three weeks later. The prognosis was evaluated at 3 weeks, 6 and 18 months postoperatively. Neither calf showed any other postoperative sequelae. This is the first case study to report the diagnosis, treatment, and prognosis of BSP in Hanwoo.
6.Comparison of the bovine blood gas parameters produced with three types of portable blood gas analyzers
Younghye RO ; Woojae CHOI ; Leegon HONG ; Eunkyung KIM ; Eunhui CHOE ; Danil KIM
Journal of Veterinary Science 2022;23(4):e60-
Background:
A definite diagnosis should be made in the bovine practice field, however, it was difficult to perform laboratory analysis immediately. Currently, three types of portable blood gas analyzers are available in Korea.
Objectives:
This study aimed to evaluate the correlations among these three analyzers.
Methods:
Seventy-two plasma samples from Holstein-Friesian cows were used for blood gas analysis, and three instruments (EDAN i15 Vet, VETSCAN i-STAT, and EPOC) were operated simultaneously. Moreover, plasma calcium levels were compared between these portable analyzers and blood chemistry device, which is usually used in a laboratory environment.Pearson analysis was performed to confirm the correlation of each parameter produced with the three instruments and blood chemistry analyzer.
Results:
As results, high correlation was observed in parameters of pH, pO2 , potassium ion, ionized calcium, and glucose (p < 0.001, r > 0.7). In addition, pCO 2 showed a moderate correlation among the three analyzers (p < 0.001, r > 0.5), and there was no correlation among all instruments for sodium ions. There was also a high correlation between ionized calcium from the three portable devices and total calcium from the biochemistry analyzer (p < 0.001, r > 0.9).
Conclusions
In conclusion, there was a high correlation between results from the three different blood gas analyzers used in the bovine clinical field in Korea. Thus, a consistent diagnosis can be made even with different equipment if the operator is aware of the strengths and weaknesses of each piece of equipment and operates it properly.
7.Risks of Completed Suicide of Community Individuals with ICD-10 Disorders Across Age Groups: A Nationwide Population-Based Nested Case-Control Study in South Korea
Eun Jin NA ; Hyewon LEE ; Woojae MYUNG ; Maurizio FAVA ; David MISCHOULON ; Jong Woo PAIK ; Jin Pyo HONG ; Kwan Woo CHOI ; Ho KIM ; Hong Jin JEON
Psychiatry Investigation 2019;16(4):314-324
OBJECTIVE: Suicide is the leading cause of death in 10–39-year-olds in South Korea, and the second highest rate among the OECD countries. However, few studies have investigated the particularity of completed suicide in South Korea. METHODS: Study subjects consisted of 2,838 suicide cases and 56,758 age and sex matched living controls from a national representative sample of 1,025,340 South Koreans. They were obtained from the Korean National Health Insurance Service-National Sample Cohort (NHIS-NSC) with follow-up up to 12 years. We obtained information on primary diagnosis of any ICD-10 disorder along with suicide cases during their lifetime. RESULTS: Among ICD-10 disorders, depression was the most common disorder (19.10%, n=542), found in victims of completed suicides except for common medical disorders such as hypertensive crisis, respiratory tract infection or arthropathies. After adjusting for sex, age, economic status, disability, and disorders, schizophrenia showed the strongest association with suicide (AOR: 28.56, 95% CI: 19.58–41.66) among all ICD-10 disorders, followed by psoriasis, multiple body injury, epilepsy, sleep disorder, depression, and bipolar disorder. For age groups, ≤19 years was associated with anxiety disorder (AOR=80.65, 95% CI: 13.33–487.93), 20–34 years with epilepsy (AOR=134.92, 95% CI: 33.69–540.37), both 35–49 years (AOR=108.57, 95% CI: 37.17–317.09) and 50–65 years (AOR=189.41 95% CI: 26.59–1349.31), with schizophrenia, and >65 years (AOR=44.7, 95% CI: 8.93–223.63) with psoriasis. CONCLUSION: Psychiatric and physical disorders carried greatly increased risks and numbers of suicides in South Korea. Schizophrenia was the strongest risk factor, especially 35–65 years, and depression was the most common in suicide victims among ICD-10 disorders in South Korea.
Anxiety Disorders
;
Bipolar Disorder
;
Case-Control Studies
;
Cause of Death
;
Cohort Studies
;
Depression
;
Diagnosis
;
Epilepsy
;
Follow-Up Studies
;
Humans
;
Insurance, Health
;
International Classification of Diseases
;
Korea
;
National Health Programs
;
Organisation for Economic Co-Operation and Development
;
Psoriasis
;
Respiratory Tract Infections
;
Risk Factors
;
Schizophrenia
;
Sleep Wake Disorders
;
Suicide
8.Risk Factors of Behavioral and Psychological Symptoms in Patients with Alzheimer Disease: The Clinical Research of Dementia of South Korea Study.
Sunyoung PARK ; Doh Kwan KIM ; Woojae MYUNG ; Jun Hyun YOO ; Su Jeong SHIN ; Duk L. NA ; Sang Yun KIM ; Jae Hong LEE ; Seong Yoon KIM ; Seol Heui HAN ; Seong Hye CHOI ; Jinyoung SHIN
Korean Journal of Family Medicine 2019;40(1):16-21
BACKGROUND: Few studies have evaluated risk factors for behavioral and psychological symptoms of dementia at the initial assessment for Alzheimer disease in large patient samples. In this study, the factors influencing Alzheimer disease were examined using the Clinical Research of Dementia of South Korea data. METHODS: This cross-sectional study was conducted using data of 1,128 patients with Alzheimer disease. The behavioral and psychological symptoms of dementia were examined using the Korean version of the Neuropsychiatric Inventory. Demographic characteristics, health-related behavior, neuropsychological tests, comorbidities, blood test results, and caregiver characteristics were assessed. Median logistic regression analysis with adjustment for covariates was conducted. RESULTS: The behavioral and psychological symptoms of dementia were negatively associated with memory (P=0.022) and frontal/executive (P < 0.001) function in the Seoul Neuropsychological Screening Battery-dementia, Barthel Index for Activities of Daily Living (P < 0.001), Korean version of the Mini-Mental State Examination score (P=0.003), and caregiver age (P=0.005) after adjustment for confounding factors, and positively associated with the Seoul-Instrumental Activities of Daily Living score (P < 0.001), Clinical Dementia Rating Sum of Box (P < 0.001), Global Deterioration Scale score (P < 0.001), abnormality of free T4 level (P < 0.001), anemia (P < 0.001), and family history of stroke (P=0.001). Patients with female caregivers exhibited more severe behavioral and psychological symptoms of dementia than those with male caregivers. CONCLUSION: Behavioral and psychological symptoms of dementia in Alzheimer disease patients were associated with various risk factors including the inability to live independently and Alzheimer disease severity. These findings suggest that prevention and treatment strategies for the behavioral and psychological symptoms of dementia should be comprehensive.
Activities of Daily Living
;
Alzheimer Disease*
;
Anemia
;
Behavioral Symptoms
;
Caregivers
;
Comorbidity
;
Cross-Sectional Studies
;
Dementia*
;
Female
;
Hematologic Tests
;
Humans
;
Korea*
;
Logistic Models
;
Male
;
Mass Screening
;
Memory
;
Neuropsychological Tests
;
Risk Factors*
;
Seoul
;
Stroke
9.Prepubertal growth and single nucleotide polymorphism analysis of the growth hormone gene of low birth weight Holstein calves
Younghye RO ; Woojae CHOI ; Hoyung KIM ; Hojin JANG ; Hoseon LEE ; Yoonseok LEE ; Danil KIM
Journal of Veterinary Science 2018;19(1):157-160
Holstein calves weighing less than 20 kg at birth have been noted in Korea. Due to insufficient information, we raised small calves with age-matched normal birth weight Holstein calves and determined body weights before puberty. In addition, 3 single nucleotide polymorphisms (SNPs) of the growth hormone (GH) gene were analyzed. Up to 10 months of age, low birth weight calves were smaller than normal weight calves. In exon 5 of the GH gene, SNP genotype variation was detected in some small calves; however, this did not appear to be the only factor inducing low birth weight and slow growth.
Adolescent
;
Birth Weight
;
Body Weight
;
Exons
;
Genotype
;
Growth Hormone
;
Humans
;
Infant, Low Birth Weight
;
Infant, Newborn
;
Korea
;
Parturition
;
Polymorphism, Single Nucleotide
;
Puberty
10.Extrapyramidal Signs and Risk of Progression from Mild Cognitive Impairment to Dementia: A Clinical Research Center for Dementia of South Korea Study.
Woojae MYUNG ; Jin Hong PARK ; Sook Young WOO ; Seonwoo KIM ; Sang Ha KIM ; Jae Won CHUNG ; Hyo Shin KANG ; Shinn Won LIM ; Junbae CHOI ; Duk L NA ; Seong Yoon KIM ; Jae Hong LEE ; Seol Heui HAN ; Seong Hye CHOI ; Sang Yun KIM ; Bernard J CARROLL ; Doh Kwan KIM
Psychiatry Investigation 2017;14(6):754-761
OBJECTIVE: Extrapyramidal signs (EPS) are common in patients with mild cognitive impairment (MCI). However, few studies have assessed the effect of EPS on the clinical course of MCI. We aimed to evaluate whether patients with EPS show more frequent progression from MCI to Alzheimer's disease (AD) and to other types of dementia. METHODS: Participants (n=882) with MCI were recruited, and were followed for up to 5 years. The EPS positive group was defined by the presence of at least one EPS based on a focused neurologic examination at baseline. RESULTS: A total of 234 converted to dementia during the follow-up period. The risk of progression to AD was lower in the patients with EPS after adjusting for potential confounders [hazard ratio (HR)=0.70, 95% confidence interval (CI)=0.53–0.93, p=0.01]. In contrast, the patients with EPS had a six-fold elevated risk of progression to dementia other than AD (HR=6.33, 95%CI=2.30–17.39, p < 0.001). CONCLUSION: EPS in patients with MCI is a strong risk factor for progression of MCI to non-Alzheimer dementia. The careful neurologic examination for EPS in patients with MCI can yield important clinical information for prognosis.
Alzheimer Disease
;
Dementia*
;
Follow-Up Studies
;
Humans
;
Korea*
;
Mild Cognitive Impairment*
;
Neurologic Examination
;
Prognosis
;
Risk Factors

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