유두상 에크린 한선종 1예

최현성,이지현,윤석권,김한욱,임철완 대한피부과학회 2004 大韓皮膚科學會誌 Vol.42 No.3

Papillary eccrine adenoma is a rare benign sweat gland neoplasm. It occurs most often as a solitary nodule in women and is located predominantly on the distal portion of the extremities. This tumor is similar to tubular apocrine adenoma in histological and clinical aspects, so distinction of these tumors is still controversial. We report a case of two papillary eccrine adenomas developed on the left popliteal and calf area of a 58-year-old-man, this is the first report of the multiple papillary eccrine adenomas in Korea. (Korean J Dermatol 2004;42(3):353~355)

3년간 계속 재발을 보이는 ENL 증례 1예

이지현,최현성,임철완 대한나학회 2003 대한나학회지 Vol.36 No.2

한국멸종위기담수어종열목어(Brachymystax lenok tsinlingensis)의유전적 다양성과집단구조: 미래복원을위한보존의미a

Ji Eun Jang,Jae Hwan Kim,Ji Hyoun Kang,Song Yi Baek,Hwang Goo Lee,Jun Kil Choi,Jae Seok Choi,Hyuk Je Lee 한국환경생태학회 2016 한국환경생태학회 학술대회지 Vol.2016 No.1

Brachymystax lenok tsinlingensis (family Salmonidae), cold freshwater fish, is endemic to Asia. This species is currently distributed throughout Russia, Mongolia, China and the Korean Peninsula. B. lenok tsinlingensis in South Korea was severely affected by anthropogenic activities such as habitat destruction, agricultural run-off and water pollution, and hence this fish has recently been dramatically decreased in its population sizes and become now critically endangered. To recover the number of individuals of B. lenok tsinlingensis, stocking or translocation programs have been conducted continuously by local governments since 1970s. However, these programs made little effort to clarify populations that may have originated from stocked, translocated or introduced fish. An understanding of genetic characteristics of endangered populations is critical to develop effective conservation and restoration plans especially because genetic diversity ensues their future fate. Therefore, we assessed the “conservation status” of this species by estimating the level of genetic diversity and genetic structure among ten geographic populations including restored populations via reinforcement and supplementation. Also, we aimed to trace the genetic origins of the newly translocated population (Chiak) through a restoration practice program. Moreover, we inferred the phylogenetic relationships among Korean lenok populations as well as across the Northeast Asia. Two hundred eighteen individuals of B. lenok tsinlingensis were sampled from ten localities (Yanggu, Injae, Seorak, Bangtae and Hongcheon: North Han River basin; Pyeongchang, Chiak and Jeongseon: South Han River basin; Taebaek and Bonghwa: Nakdong River basin in South Korea). Based on mitochondrial DNA (mtDNA) control region and eight nuclear microsatellite loci, we found extremely low levels of within-population genetic diversity, which suggests small effective population sizes (Ne) within populations. For mtDNA control region, each population housed one, or at most, two haplotypes that are restricted to the respective localities, meaning that these ‘genetically unique’ lineages will be lost permanently if the local populations undergo extinction. The overall values of haplotype diversity (h) and nucleotide diversity (π) for the entire Korean population were 0.703 ± 0.024 and 0.021 ± 0.010, respectively. In the case of microsatellites, average number of alleles across the eight loci for the entire population was 9.1 and allelic richness (AR) per population ranged from 2.375 to 4.144 (mean = 3.104). The values of observed heterozygosity (HO) and expected heterozygosity (HE) were similar to each other [HO: 0.400 ~ 0.590 (mean = 0.518); HE: 0.407 ~ 0.608 (mean = 0.504)]. The inbreeding coefficient (FIS) values were generally low, ranging from 0.048 to 0.279. Consequently, the majority of the populations (except Yanggu and Pyeongchang) were not significantly deviated from Hardy-Weinberg equilibrium (HWE), suggesting random mating at these loci tested. In addition, we found that Korean lenok populations were significantly genetically isolated from each other, with private mtDNA haplotypes and microsatellite alleles, indicating limited gene flow among populations, strong effects of genetic drift due to small Ne, or a combination of both. The Mantel test of microsatellites revealed a significant correlation (r = 0.414, P = 0.04) between genetic and geographic distances for pairwise comparisons among the ten populations, while that of mtDNA showed a lack of correlation. Given the shared identical mtDNA haplotype and similar microsatellite allelic distributions between Chiak and Hongcheon populations, we suggest that the restored (introduced) Chiak population would be inferred to be genetically originated from Hongcheon population. Phylogenetic relationships among Northeast Asian populations showed that South Korean lineages have more recently diverged from China (Yellow River), than between North Korea and Russia. Although the phylogenetic relationship would be expected to be associated with geography, South-North Korea and China populations with a similar latitude was more phylogenetically closely related. These findings may suggest a possible scenario for the historical movements of B. lenok tsinlingensis in Northeast Asia during Last Glacial Maximum (LGM). It would be supported by the line of evidence that most lenok populations migrated to southward from Northern Asia such as Russia and Mongolia during LGM because the Korean Peninsula was landlocked as inland epoch and functioned as a southern shelter with Yellow River. For this reason, the Korean Peninsula is suggested to be an important geographical region for better understanding phylogenetic relationships and evolutionary histories of B. lenok tsinlingensis across the Northeast Asia. Despite large efforts made to develop several restoration programs in South Korea for B. lenok tsinlingensis, it is still unknown whether these past restoration efforts were successful or fruitless, mainly because of little attention paid to post-restoration monitoring research. Hence, there was a lack of their published official records. In the future, conservation and restoration projects of the Korean lenok populations should consider the genetic data for a better understanding of their ecological and evolutionary trajectories. And finally, we hope that our findings here can help inform on the future effective conservation and restoration plans for B. lenok tsinlingensis populatio ns in South Korea.

한국 멸종위기 담수어종 열목어(Brachymystax lenok tsinlingensis)의 유전적 다양성과 집단구조: 미래 복원을 위한 보존 의미

장지은 ( Ji Eun Jang ),김재환 ( Jae Hwan Kim ),강지현 ( Ji Hyoun Kang ),백송이 ( Song Yi Baek ),이황구 ( Hwang Goo Lee ),최준길 ( Jun Kil Choi ),최재석 ( Jae Seok Choi ),이혁제 ( Hyuk Je Lee ) 한국환경생태학회 2016 한국환경생태학회 학술대회지 Vol.2016 No.1

Brachymystax lenok tsinlingensis (family Salmonidae), cold freshwater fish, is endemic to Asia. This species is currently distributed throughout Russia, Mongolia, China and the Korean Peninsula. B. lenok tsinlingensis in South Korea was severely affected by anthropogenic activities such as habitat destruction, agricultural run-off and water pollution, and hence this fish has recently been dramatically decreased in its population sizes and become now critically endangered. To recover the number of individuals of B. lenok tsinlingensis, stocking or translocation programs have been conducted continuously by local governments since 1970s. However, these programs made little effort to clarify populations that may have originated from stocked, translocated or introduced fish. An understanding of genetic characteristics of endangered populations is critical to develop effective conservation and restoration plans especially because genetic diversity ensues their future fate. Therefore, we assessed the “conservation status” of this species by estimating the level of genetic diversity and genetic structure among ten geographic populations including restored populations via reinforcement and supplementation. Also, we aimed to trace the genetic origins of the newly translocated population (Chiak) through a restoration practice program. Moreover, we inferred the phylogenetic relationships among Korean lenok populations as well as across the Northeast Asia. Two hundred eighteen individuals of B. lenok tsinlingensis were sampled from ten localities (Yanggu, Injae, Seorak, Bangtae and Hongcheon: North Han River basin; Pyeongchang, Chiak and Jeongseon: South Han River basin; Taebaek and Bonghwa: Nakdong River basin in South Korea). Based on mitochondrial DNA (mtDNA) control region and eight nuclear microsatellite loci, we found extremely low levels of within-population genetic diversity, which suggests small effective population sizes (Ne) within populations. For mtDNA control region, each population housed one, or at most, two haplotypes that are restricted to the respective localities, meaning that these ‘genetically unique’ lineages will be lost permanently if the local populations undergo extinction. The overall values of haplotype diversity (h) and nucleotide diversity (π) for the entire Korean population were 0.703 ± 0.024 and 0.021 ± 0.010, respectively. In the case of microsatellites, average number of alleles across the eight loci for the entire population was 9.1 and allelic richness (AR) per population ranged from 2.375 to 4.144 (mean = 3.104). The values of observed heterozygosity (HO) and expected heterozygosity (HE) were similar to each other [HO: 0.400 ~ 0.590 (mean = 0.518); HE: 0.407 ~ 0.608 (mean = 0.504)]. The inbreeding coefficient (FIS) values were generally low, ranging from 0.048 to 0.279. Consequently, the majority of the populations (except Yanggu and Pyeongchang) were not significantly deviated from Hardy-Weinberg equilibrium (HWE), suggesting random mating at these loci tested. In addition, we found that Korean lenok populations were significantly genetically isolated from each other, with private mtDNA haplotypes and microsatellite alleles, indicating limited gene flow among populations, strong effects of genetic drift due to small Ne, or a combination of both. The Mantel test of microsatellites revealed a significant correlation (r = 0.414, P = 0.04) between genetic and geographic distances for pairwise comparisons among the ten populations, while that of mtDNA showed a lack of correlation. Given the shared identical mtDNA haplotype and similar microsatellite allelic distributions between Chiak and Hongcheon populations, we suggest that the restored (introduced) Chiak population would be inferred to be genetically originated from Hongcheon population. Phylogenetic relationships among Northeast Asian populations showed that South Korean lineages have more recently diverged from China (Yellow River), than between North Korea and Russia. Although the phylogenetic relationship would be expected to be associated with geography, South-North Korea and China populations with a similar latitude was more phylogenetically closely related. These findings may suggest a possible scenario for the historical movements of B. lenok tsinlingensis in Northeast Asia during Last Glacial Maximum (LGM). It would be supported by the line of evidence that most lenok populations migrated to southward from Northern Asia such as Russia and Mongolia during LGM because the Korean Peninsula was landlocked as inland epoch and functioned as a southern shelter with Yellow River. For this reason, the Korean Peninsula is suggested to be an important geographical region for better understanding phylogenetic relationships and evolutionary histories of B. lenok tsinlingensis across the Northeast Asia. Despite large efforts made to develop several restoration programs in South Korea for B. lenok tsinlingensis, it is still unknown whether these past restoration efforts were successful or fruitless, mainly because of little attention paid to post-restoration monitoring research. Hence, there was a lack of their published official records. In the future, conservation and restoration projects of the Korean lenok populations should consider the genetic data for a better understanding of their ecological and evolutionary trajectories. And finally, we hope that our findings here can help inform on the future effective conservation and restoration plans for B. lenok tsinlingensis populatio ns in South Korea.

사인파 활성화 함수를 적용한 합성곱 신경망 기반 JPEG 압축 영상 디블로킹 연구

최지현(Ji-Hyoun Choi),박수용(Suyong Bahk),김영웅(Yeongwoong Kim),김휘용(Hui Yong Kim) 한국방송·미디어공학회 2023 한국방송공학회 학술발표대회 논문집 Vol.2023 No.6

사인파 활성화 함수 (SIREN, Sinusoidal Activation Function) 는 암시적 신경 표현 (INR, Implicit Neural Network) 분야에서 ReLU (Rectified Linear Unit) 활성화 함수에 비해 높은 성능을 보여 널리 사용되었다. 본 논문에서는 사인파 활성화 함수가 이미지의 연속적인 변화를 포착하는 능력이 뛰어나다는 점에 기인하여, 각 블록 간의 경계를 부드럽게 이어주는 디블로킹 (Deblocking) 모델에 해당 활성화 함수를 여러가지 방식으로 적용하고 성능을 비교한다. 본 연구를 통해 사인파 활성화 함수를 합성곱 신경망 (CNN, Convolutional Neural Network) 기반 모델에 적용하는 방법에 대한 통찰을 제공한다.

농촌노인 돌봄 프로그램 키워드 분석 : 지역사회보장계획을 중심으로

최현우(Hyoun Woo Choi),손주리(Joo Lee Son),최윤지(Yoon JI Choi),최정신(Jung Shin Choi) 한국지역사회생활과학회 2023 한국지역사회생활과학회 학술대회 자료집 Vol.2023 No.5

Poster Session : PS 0663 ; Rheumatology ; The Seasonality of Gout Onset and Flares in Korea

( Hyo Jin Choi ),( Chan Hee Lee ),( Joo Hyun Lee ),( Bo Young Yoon ),( Hyoun Ah Kim ),( Chang Hee Suh ),( Sang Tae Choi ),( Jung Soo Song ),( Hoyeon Joo ),( Sung Jae Choi ),( Ji Soo Lee ),( Kee Chul S 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

Background: To evaluate seasonality of gout onset and fi ares in Korea. Methods: We retrospectively examined data from 330 patients seen at nine rheumatology multicenter clinics, under urate lowering therapy (ULT) more than one year after stopping prophylactic medication. Demographic data, clinical and laboratory features and seasonality of gout fi are were collected. Season was classifi ed as three-month time intervals (the period from March through May was defi ned as spring). Results: The mean age was 52.2 years and mean disease duration was 26.8 months. The male to female count was 318:12. The season of gout onset was most common in summer (28.5%). During ULT, 113 of the 330 patients (34.2%) experienced at least one gouty attack in the period from stopping prophylaxis to one year later. Total gout fi ares were one hundred forty-seven (male 97.3%). Gout fi ares were most common in summer (30.6%), and then fall (25.2%), spring (22.4%), and winter (21.8%). The most common month of fi are was June (13.6%), following by August (10.2%), September (9.5%) and February (9.5%). The aggravating factor was identifi ed in 60 fi ares; alcohol (68.3%), concomitant drugs (13.3%), food (10.0%), and work/exercise (8.3%). The proportion of alcohol in summer was higher (88.9%) than other seasons. In the patients with attained to the target serum uric acid (< 6mg/dL) at the end of prophylaxis (n=52), gout fi ares were most common in fall (35.8%) and September (17.0%). Conclusions: Gout onset of Korea was most common in summer. The summer and fall were most common seasons of gout fi are during ULT. We suggested that increased physical activity, changes of temperature, dehydration and alcohol consumption might be associated with our results.

Comparison of Renal Responses to Cyclophosphamide and Mycophenolate Mofetil used as Induction Therapies in Korean Patients with Lupus Nephritis

( Sung-eun Choi ),( Dong-jin Park ),( Ji-hyoun Kang ),( Kyung-eun Lee ),( Haimuzi Xu ),( Ji Shin Lee ),( Yoo-duk Choi ),( Shin-seok Lee ) 대한류마티스학회 2019 대한류마티스학회지 Vol.26 No.1

Objective. Although intravenous cyclophosphamide (IVC) is generally accepted as the standard therapy for induction treatment of active proliferative lupus nephritis (LN), several clinical trials have suggested that mycophenolate mofetil (MMF) is at least as effective as IVC. Because few Asian studies have compared the two treatment modalities, we compared the efficacies of MMF and IVC as LN remission induction treatments in Korean patients. Methods. We enrolled 39 patients with class III and IV LN who received MMF or IVC as LN induction therapy. The renal outcomes (i.e., complete response [CR], partial response [PR], and no response [NR]) at 6 and 12 months were defined using the ACR 2006 response criteria. Results. Of 39 patients, 23 (59.0%) were treated with IVC, and 16 (41.0%) were treated with MMF. Demographics, clinical characteristics, laboratory data, and adverse events did not significantly differ between the two groups. However, C3 levels were lower and activity scores in renal biopsy were higher in IVC-treated patients. CRs were achieved by 11 (47.8%) of the patients receiving IVC and 7 (43.8%) of the patients receiving MMF after 6 months of treatment (p=0.961) and by 11 (47.8%) of those who received IVC and 9 (56.2%) of those who received MMF at 12 months of treatment (p=0.713). Neither the PR rate nor the NR rate differed significantly at 6 or 12 months between the two groups. Conclusion. The efficacy of MMF does not differ from that of IVC in terms of induction of LN remission in Korean patients. (J Rheum Dis 2019;26:57-65)

Toxoflavin/tflA selection-based new indica rice transformation

Eun-Hye Kim,Ji-Hyoun Choi,Ji-Hoon Park,Raksha Singh,Nam-Soo Jwa 한국육종학회 2012 한국육종학회 심포지엄 Vol.2012 No.07

Most indica rice varieties show a low efficiency of transformation because of difficulties in callus formation and low-regeneration frequencies in conventional culture such as MS16 or N6 medium. Recently, some improved methods were reported for Agrobacterium-mediated transformation using mature elite indica seeds however, these procedures take a long time (5–7 months) to obtain transgenic plants and still with significantly low efficiency. In this study, we provide additional improvements in the indica rice transformation protocol introducing new selection method by tosoflavin/tflA which was based on bacterial photosensitizer and its degrading enzyme pair. We introduced direct in planta transformation using early stage of germinating rice seeds instead of usual embryogenic callus. Methods that use embryos as a starting material for inoculation with Agrobacterium are also used for comparison with the new protocol using rice seeds. Transformed cells proliferated from rice seeds obtain toxoflavin resistance, and transgenic plants are eventually regenerated from those proliferated tissues. However, we found out that tissue proliferation from indica seeds and shooting and rooting are very sensitive to minor salt nutrients in the media and need to pay attention to use indica rice specific nutrient media. The use of naturally occurring photosensitizers such as toxoflavin as selection agents appears to give rapid and unambiguous selection results owing to their unique phytotoxic mode of action. In particular, the toxoflavin/tflA selection system might be useful for generating transgenic indica rice cultivar where high false-positive backgrounds with current selection marker systems are problematic.

한국제주도및남해연안에서식하는잘피거머리말의집단유전학구조a

Jae Hwan Kim,Ji Hyoun Kang,Sun Kyeong Choi,Sangil Kim,Ji Eun Jang,Hyuk Je Lee,Sang Rul Park 한국환경생태학회 2016 한국환경생태학회 학술대회지 Vol.2016 No.1

Seagrasses, sea flowering plants, comprise approximately 60 species globally and are often called ‘ecosystem engineers’ because they create their own habitats by modifying the surrounding environments, which provide coastal zones with a number of crucial ecosystem services. Zostera marina (the common name ‘eelgrass’) is one of the seagrass beds-forming species distributed widely in northern hemisphere including the Korean coast, which plays a pivotal role in ecosystem as a primary producer and a nursery habitat or refuge for other marine organisms. However, due to global climate change and anthropogenic activities such as reclamation and dredging, there has recently been a drastic decline in population sizes of Z. marina in Korea. In order to develop effective conservation and restoration management programs of Z. marina populations, it would be helpful to consider all biological aspects of this species such as genetic characteristics as well as ecological and physiological features. This study first provides information on genetic diversity and genetic structure of Jeju Island and Namhae populations of Z. marina, which will contribute to the establishment of appropriate conservation and restoration management plans for future persistence of this species. Using six microsatellite markers, we investigated the level of genetic diversity and genetic structure among 10 geographic populations of Z. marina inhabiting Jeju Island (Hamdeok, Tokki-seom, Sungsan, Woljeong, Ojo) and Namhae (Gamak bay, Jindong bay, Nampo, Anggang bay, Geoje) on the southern coast of Korea. The level of genetic diversity within Jeju populations (mean allelic richness [AR]: 1.57 ~ 3.09) was found to be significantly lower than Namhae populations (AR: 3.09 ~ 4.29) (Mann-Whitney U-test, P < 0.05). These findings suggest that effective population sizes (Ne) of Jeju populations are generally smaller than those of Namehae populations. Within Jeju Island, Hamdeok population had the smallest population size (coverage: 138 m2) and the lowest genetic diversity (AR: 1.57), while Ojo population had the largest population size (coverage: 275,736 m2) and the greatest level of genetic diversity (AR: 3.09). Hamdeok population showed evidence of genetic bottleneck. These results again suggest that Ne of Jeju populations is generally low (except Ojo population). Among Jeju populations, all pair-wise comparisons of FST values (i.e., degree of genetic differentiation) were highly significant (FST = 0.0612 ~ 0.7168, P < 0.001) despite Jeju populations that were geographically closely located, indicating that these local populations are genetically divergent, probably due to a lack of gene flow among the populations. The observed strong population structure was substantiated by evidence that five genetic clusters are most likely, based on population assignment test (STRUCTURE). The Mantel test showed a positive relationship between genetic distance (FST) and geographic distance (km) across all the populations sampled (R2 = 0.4118, P < 0.05), suggesting that our data follow Isolation By Distance (IBD) model. Woljeong population revealed the highest level of FST values compared to other populations within Jeju Island in IBD. STRUCTURE and factorial correspondence analysis (FCA) further showed that some Woljeong individuals included genotypes of Namhae populations. Population size of Woljeong (coverage: 310m2) was approximately 50 % smaller than that of Sungsan (coverage: 841m2); however, extent of its genetic diversity (AR: 2.39) was even higher than that of Sungsan population (AR: 1.77). We speculated that Woljeong population underwent a transplantation from Namhae populations with relatively higher level of genetic diversity. FST values within Namhae populations were relatively lower (compared to within Jeju Island) despite the populations that were geographically more distant. It means that level of gene flow is higher among Namhae populations than among Jeju populations. Z. marina is known to have different life histories by water depth. In subtidal zone (deep water depth) populations predominantly undertake sexual reproduction through seeds such as annual life history, whereas those of intertidal zone (shallow water depth) undertake both sexual and asexual reproductions through horizontal rhizomes i.e., perennial life history. STRUCTURE analysis showed no clear differences between shallow and deep populations at Namhae, but some FST values were statistically significantly different despite their low values. For Geoje population sampled in 2005, intertidal and subtidal populations were not significantly different (FST = 0.0045, P = 0.033), but these populations sampled in 2015 showed a significant difference (FST = 0.0328, P < 0.001). It means that genetic structure of Geoje has been changed over the 10 year period between shallow and deep populations. Overall, the Jeju and Namehae populations analyzed in the current study have relatively low levels of genetic diversity and distinct genetic compositions, which warns the message that this ecologically important species should be conserved separately in the local populations and with high priority. We propose that future conservation and restoration plans for seagrasses should consider genetic characteristics particularly because a close relationship between genetic diversity and ecological performance in marine species has been well documented.