New Zealand White 토끼의 생식세포 및 체세포 분열에 의한 염색체 분석

신선희,김희수,최영현,이원호 부산대학교 유전공학연구소 2001 분자생물학 연구보 Vol.17 No.-

토끼(New Zealand White rabbit)의 감수분열 및 유사분령상을 통해 그 염색체적 특징을 조사하였다. 감수분열 염색체의 표본 작성은 공기건조법을 다소 변형하여 사용하였고, 유사분열 중기상의 핵형분석에는 G-분염법을 이용하여 다음과 같은 결과를 얻었다. 1. 제1감수분열의 접합기와 태사기의 염색소립과 sex vesicles 및 동원체가 뚜렷하게 구별되었다. 태사기의 중기에서부터 후기 과정이 진행되는 동안에 2가염색체에서 측면으로 돌출한 머리카락 모양의 돌기들이 관찰되어졌고, 이 돌기들은 염색체가 lampbrush 염색체 구조의 모양이 되도록 해주었다. 이동기의 염색체들은 키아즈마의 수와 위치에 따라 분류가 가능하였다. 제1 감수분열 전기의 후반부 과정과 중기Ⅰ 시기에는 2가염색체로 된 21개의 상염색체와 1개의 말단결합으로 연결된 X-Y 염색체를 관찰할 수 있었다. 2. New Zealand White rabbit의 생식세포에서 관찰된 2가 염색체의 형태는 1CH, 1TAl 및 2TA 2가염색체 유형이 대부분을 이루었다. New Zealand White rabbit에서의 평균 키아즈마 빈도는 약 30.2로 나타났으며, 키아즈마 빈도가 복사기, 이동기 및 중기Ⅰ로 분열이 진행됨에 따라 다소 감소하는 경향이 있었다. 3. New Zealand White rabbit의 핵형분석에 의하면 염색체 수는 44개(2n=44)로서, 8쌍의 중부염색체, 9쌍의 차중부염색체, 4쌍의 단부염색체로 된 21쌍의 상염색체와 중부염색체인 1개의 X 염색체 및 단부염색체인 1개의 Y 염색체로 구성되어 있음을 알 수 있었다. Chromosomal characteristics of New Zealand White rabbit was studied at meiosis and mitosis. The meiotic chromosomal preparations were made with the modified air-drying method and karyotype analysis was performed with the G-banding technique, using isolated mitotic metaphase chromosomes of the New Zealand White rabbit. Chromosomes, sex vesicles and centromeres could be could be classified in the zygotene and the pachytene of the meiosis Ⅰ. The hair-like processes projecting laterally from the axes of bivalent chromosomes at the mid-late pachytene were basis of the numbers and the locations of chiasma in the diakinesis. Twenty-one autosomal bivalents and a single unequal terminally associated X-Y bivalent were observed during the late prophase and the metaphase of the meiosis Ⅰ. Most of the bivalent types observed in the New Zealand White rabbit spermatocytes were 1CH, 1TAl, and 2TA bivalents. The mean chiasma frequency (CE) of the male New Zealand White rabbit was 30.2, and it was found that the CF value tended to decrease through the diakinesis and the metaphase Ⅰ. The karyotype of the New Zealand White rabbit was a male chromosome number of 44(2n=44), comprising 8 pairs of metacentric, 9 pairs of submetacentric, 4 pairs of acrocentric autosomes, metacentric X chromosome and acrocentric Y chromosome.

소수성 촉매를 이용한 수소동위원소 교환 반응 측정을 위한 순환 반응기

최희주,이한수,안도희,강희석,김광락 한국공업화학회 2002 응용화학 Vol.6 No.2

The catalytic rate constants of hydrophobic catalysts developed for the removal of tritium mainly generated in the pressurized heavy water reactors should be measured. A recycle reactor was designed and built for characterzing the long-term behavior of the catalyst performance at the various temperatures and gas velocities.The catalytic rate constants were measured at the apparent gas velocity of 0.5 m/s and the temperature of 60℃. The initial catalytic constant was 8.44×10^-4mol/g.sec. This value is much greater than that considered in the design of Wolsong Tritium Removal Facility.

인슐린 비의존형 당뇨병 환자에서 혈장 Endothelin-1농도의 변화

신양수,조희충,김원식,국기용,김용화,정종훈,문철웅,배학연,양성훈 朝鮮大學校 附設 醫學硏究所 1992 The Medical Journal of Chosun University Vol.17 No.2

Endothelin(ET) is a 21-residue peptide originally isolated from the cultured porcine endothelial cells. There are at least three genes for endothelin:endothelin-1(ET-1), endothelin-2(ET-2), and endothelin-3(ET-3). Endothelins are present in various human biological fluids including plasma, urine, breast milk, and saliva and have been found elevated plasma ET concentrations in patients with diabetes mellitus, Patients undergoing maintenance hemodialysis due to chronic renal failure, patients with acute myocardial infarction, and patients with subarachnoid hemorrhage. Endothelial cell damage is suspected to occur in diabetic patients and may be one important cause of angiopathy, a major complication in diabetes mellitus. The elevation of ET in diabetic patients may be a marker of, and further exacerbate, their vascular disease. We measured the levels of ET-1 in plasma of 50 patients with non-insulin dependent diabetes mellitus(NIDDM) and 25 normal subjects by radioimmunoassay. The plasma ET-1 concentration (mean±S.D.) in NIDDM was 6.461 A2.510 f㏖/ ㎖, and was significantly higher than in normal subjects (4.567±1.155f㏖/㎖) (P<0.05). The plasma ET-1 concentration (mean±S.D.) in diabetic retinopathy group( 7.15±2.454 f㏖/ml) was significantly elevated than those in otherwise uncomplicated groups (5.348±2.390 f㏖/㎖)(P<0.01). The correlation between any clinical parameters and plasma ET-1 levels in NIDDM was not significant, In conclusion, this study suggest that the elevated levels of ET-1 in diabetic patients may be play a important role in the pathogenesis of diabetic complications.

크래시된 이미지와 딥 클러스터링을 통한 크래시 분류 개선

김요한 ( Yo-han Kim ),이상준 ( Sang-jun Lee ) 한국정보처리학회 2019 한국정보처리학회 학술대회논문집 Vol.26 No.2

소프트웨어 크래시 분류를 개선하기 위해 호출 스택 정보를 기반한 많은 연구들이 있다. 본 연구에서는 크래시 직전 이미지를 수집하여, 기존 호출 스택 기반의 분류에서 발생하는 문제를 개선하고자 한다. 또한 이미지 자체의 직관성으로 개발자뿐만 아니라 개발 지식이 없는 실무자도 크래시 정보를 활용할 수 있고, 문제 해결을 위한 재현 루트 파악, 위변조 여부와 같은 추가 정보를 확인할 수 있을 것으로 기대한다. 비지도 학습 기반인 딥러닝 클러스터링 N2D 알고리즘을 통하여 이미지를 자동 분류하고 순위화하는 시스템을 구축하여, 특정 소프트웨어에 특화되지 않고 다양한 소프트웨어의 크래시 이미지 자동 분류에 기여할 수 있을 것으로 기대한다.

Genome-wide target specificities of CRISPR RNA-guided programmable deaminases

Kim, Daesik,Lim, Kayeong,Kim, Sang-Tae,Yoon, Sun-heui,Kim, Kyoungmi,Ryu, Seuk-Min,Kim, Jin-Soo Nature Publishing Group, a division of Macmillan P 2017 Nature biotechnology Vol.35 No.5

<P>Cas9-linked deaminases, also called base editors, enable targeted mutation of single nucleotides in eukaryotic genomes. However, their off-target activity is largely unknown. Here we modify digested-genome sequencing (Digenome-seq) to assess the specificity of a programmable deaminase composed of a Cas9 nickase (nCas9) and the deaminase APOBEC1 in the human genome. Genomic DNA is treated with the base editor and a mixture of DNA-modifying enzymes in vitro to produce DNA double-strand breaks (DSBs) at uracil-containing sites. Off-target sites are then computationally identified from whole genome sequencing data. Testing seven different single guide RNAs (sgRNAs), we find that the rAPOBEC1-nCas9 base editor is highly specific, inducing cytosine-to-uracil conversions at only 18 +/- 9 sites in the human genome for each sgRNA. Digenome-seq is sensitive enough to capture off-target sites with a substitution frequency of 0.1%. Notably, off-target sites of the base editors are often different from those of Cas9 alone, calling for independent assessment of their genome-wide specificities.</P>

Hot snare polypectomy with or without saline solution/epinephrine lift for the complete resection of small colorectal polyps

Kim, Hyun-Soo,Jung, Ho Yeon,Park, Hong Jun,Kim, Hee Man,Seong, Jae Ho,Kang, Yong Seok,Cho, Mee Yon,Yu, Min Heui,Kang, Dae Ryong Elsevier 2018 Gastrointestinal endoscopy Vol.87 No.6

<P><B>Background and Aims</B></P> <P>The criteria for a standard polypectomy technique for complete removal of small colorectal polyps has not yet been established. This study aimed to compare the complete resection rate of hot snare polypectomy (HSP) with that of EMR for small, sessile, or flat polyps.</P> <P><B>Methods</B></P> <P>Patients with 5- to 9-mm non-pedunculated colorectal polyps were prospectively randomized to the HSP or EMR group. The presence of residual polyps was assessed by performing histologic assessment of 4-quadrant forceps biopsy specimens taken from the edges of the polypectomy site. The primary outcome was the complete resection rate after HSP or EMR; the secondary outcomes were the proportion of procedure-related adverse events and specimen-loss rate. Sample size was estimated using a superiority trial design. We assumed that the complete resection rate of the EMR group would be at least 8% higher than that of the HSP group.</P> <P><B>Results</B></P> <P>A total of 382 polyps in 269 patients were assessed and randomly assigned to each method using 4 × 4 block randomization. Of these, 353 polyps were finally analyzed based on the pathology results. The mean polyp size was 6.3 ± 1.3 mm. The complete resection rate did not differ between the HSP and EMR groups (88.4% [152/172] vs 92.8% [168/181], respectively; <I>P</I> = .2). The intraprocedural bleeding rate, immediately after polypectomy, was significantly higher in the HSP group than in the EMR group (5.2% vs 0.6%, respectively; <I>P</I> = .009). However, clinically significant bleeding and tissue retrieval failure rates did not differ between the groups. In the multivariate logistic regression analysis, sessile serrated adenoma/polyps or hyperplastic polyps were almost 3 times (odds ratio, 2.824; 95% confidence interval, 1.03-7.75; <I>P</I> = .044) more likely to be incompletely resected compared with other conventional adenomatous polyps. Except for pathology, we found no significant independent predictors for incomplete resection.</P> <P><B>Conclusion</B></P> <P>EMR for small non-pedunculated colorectal polyps is not superior to HSP in terms of complete resection or safety. Both methods can be performed according to the endoscopist’s preference. (Clinical trial registration number: KCT0001640; cris.nih.go.kr.)</P>

Fabrication and Charging Test of HTS Field Windings Using HTS Contactless Rotary Excitation Device

Kim, Ji Hyung,Quach, Huu Luong,Boo, Chang-Jin,Yoon, Yong Soo,Jeon, Haeryong,Han, Seunghak,Ko, Tae Kuk,Kim, Hyung-Wook,Jo, Young-Sik,Park, Heui Joo,Lee, Jihoon,Lee, Haigun,Kim, Ho Min Institute of Electrical and Electronics Engineers 2019 IEEE transactions on applied superconductivity Vol.29 No.5

<P>This paper presents the results of the fabrication and preliminary charging test of second-generation high-temperature superconducting (2G HTS) coils for the rotor field winding of a 1-kW-class HTS rotating machine (HTSRM). This machine technically employs an HTS contactless rotary excitation device (CRED), which is the so-called rotary flux pump, to charge the HTS field windings using a noncontact excitation method. In this study, the major components of the 1-kW-class HTSRM, such as the 2G HTS coils for the rotor field pole of the rotating machine, HTS strands with a toroidal head for the rotary part of CRED, and stationary part of CRED, were fabricated and assembled. Then, the charging performance of the field operating current was tested in preliminary experiments. In particular, to confirm the technical feasibility of CRED on application to the 1-kW-class HTSRM, the HTS field coils were charged under various operating conditions of the HTS CRED in a stationary flux-pump mode.</P>

Identification of novel CYP4F2 genetic variants exhibiting decreased catalytic activity in the conversion of arachidonic acid to 20-hydroxyeicosatetraenoic acid (20-HETE)

Kim, Woo-Young,Lee, Su-Jun,Min, Jungki,Oh, Kyung-Suk,Kim, Dong-Hyun,Kim, Heui-Soo,Shin, Jae-Gook Elsevier 2018 Prostaglandins, leukotrienes, and essential fatty Vol.131 No.-

<P><B>Abstract</B></P> <P>CYP4F2 is an enzyme involved in the formation of 20-hydroxyeicosatetraenoic acid (20-HETE) from arachidonic acid and metabolizes vitamin K into an inactive form. Our objectives were to identify new <I>CYP4F2</I> genetic variants and to characterize the functional consequences of the conversion of arachidonic acid into 20-HETE. We used direct DNA sequencing to identify a total of 20 single-nucleotide polymorphisms (SNPs) including four coding variants, A27V, R47C, P85A, and V433M, in 50 randomly selected subjects. Of these, A27V and P85A were new. Recombinant variant proteins were prepared using an <I>Escherichia coli</I> expression system, purified, and quantified via CO-difference spectral analysis. The conversion of arachidonic acid to 20-HETE by the coding variants was compared to that of the wild-type protein. Wild-type CYP4F2 exhibited the highest intrinsic clearance, followed by P85A, A27V, V433M, and R47C (40–65% of the wild-type value). The locations of the mutated residues in the three-dimensional protein structure were predicted by structural modeling, and the possible effects on 20-HETE synthesis discussed. In summary, we describe the allele frequency, haplotype distribution, and linkage disequilibrium of <I>CYP4F2</I> and functionally analyze the <I>CYP4F2</I> coding variants. Our findings suggest that individuals having the low-activity alleles of CYP4F2 may inefficiently convert arachidonic acid into 20-HETE. This may aid in our understanding of 20-HETE-related blood pressure problems and cardiovascular diseases when genotype-phenotype association studies are performed in the future.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Novel discovery and genetic analysis of CYP4F2 genetic polymorphisms. </LI> <LI> Identification of functionally decreased CYP4F2 coding variants in the conversion of arachidonic acid to 20-HETE. </LI> <LI> Prediction and interpretation of the mutated CYP4F2 proteins by the three-dimensional structure modeling. </LI> </UL> </P>

Interactions between human endogenous and exogenous retroviruses

Kim, Heui-Soo,Ock, Mee Sun,Cha, Hee-Jae 한국유전학회 2017 Genes & Genomics Vol.39 No.9

<P>Retrovirus genes have become inserted into the human genome for more than one million years. These retroviruses are now inactivated due to mutation, such as deletions or nonsense mutations. After mutation, retroviruses eventually become fixed in the genome in the endogenous form and exist as traces of ancient viruses. These retroviruses are called human endogenous retroviruses (HERVs). HERVs cannot make fully active viruses, but a number of viral proteins (or even virus particles) are expressed under various conditions. By comparison with ERVs, some exogenous retroviruses are still infectious and cause serious diseases threatening human life. Recent studies have shown that some elements of HERVs are closely related to other exogenous retroviruses, including human immunodeficiency virus (HIV). This review will describe the regulation and interaction between HERVs and other active viral infections. In addition, we introduce the development of vaccines and therapeutic agents against these viral infections through the use of HERV elements.</P>

Alzheimer’s disease related genes during primate evolution

Kim, Dong Hee,Gim, Jeong-An,Kim, Kwang Hee,Han, Chang Woo,Jang, Se Bok,Kim, Heui-Soo 한국유전학회 2017 Genes & Genomics Vol.39 No.11

<P>During primate evolution, the neuronal and cognition-related genes have evolved rapidly. These genes seem to induce neurological illnesses such as Alzheimer's disease (AD). In this study, we analyzed genes APOE, TOMM40, and PICALM known as the risk factors of AD. We performed bioinformatics analyses in relation to evolution, phylogeny, and protein structure for those genes in humans, Neanderthals, chimpanzees, bonobos, gorillas, orangutans, crab-eating monkeys, and rhesus monkeys. Cholesterol-related genes showed relatively rapid evolution toward a lower risk of AD. Neanderthals showed relatively higher polymorphism in genes APOE, TOMM40, and PICALM than humans did. Phylogeny indicated different topologies in the trichotomy of humans, chimpanzees, and gorillas in terms of genes APOE, TOMM40, and PICALM. These results provide to hominin-specific patterns in three genes, and give clues to the modern human-specific traits of AD and shed light on further functional research helping to understand AD.</P>