KCI, KBr에 關한 X-線 廻折硏究

李善鏞,金永銓,張忠根,徐日煥 충남대학교 자연과학연구소 1982 忠南科學硏究誌 Vol.9 No.1

The crystal structure of potassium chloride and potassium bromide have been determined by X-ray diffraction method. Both unit cells are face-centered cubic, F(4/m)3￣(2/m) z=4 but a=5.2857Å, V=248,348Å^3, D_c=1.989 gr/㎤ for KCl and a=6.5891Å, V=286.074Å^3, D_c=2.756 gr/㎤ for KBr. the structures were solved by graphical method using thirteen KCl and eleven KBr powder diffractometer data. The agreement between the experimental and theoretical integrated intensities of the reflecting planes is fairly good. The crystal are aggregates of positive and negative ionic atoms. Each atom has six nearest neighbors of the other kind. The distances between unlike atoms are 3.1429Å in KCl and 3.2945Å in KBr.

전박부 전골간신경 증후군의 치료

이상열,임병훈,하충건 大韓成形外科學會 1991 Archives of Plastic Surgery Vol.18 No.1

The anterior interosseous nerve syndrome is a compressive neuropathy of a motor branch of the median nerve, caused by tendinous bands (deep head of pronator teres, arcade of flexor superficialis, thickened lacertus fibrosus etc, trauma, enlarged bursae, tumors, anomalous muscles such as Gantser's muscle or palmaris brevis. On clinical examination, there is weakness or paralysis of the flexor pollicis longus, flexor digitorum profundus of the index finger, and the pronator quadratus muscles with a history of pain in the proximal forearm. The patients will assume a weakness of pinch or an unusual posture of pinch without sensory deficit because of loss of function of these muscles, hyperextending the interphalangeal joint of the thumb and the distal interphalangeal joint of the index finger. We experienced two cases of anterior interosseous nerve syndrome with typical clinical manifestations, confirmed by electrodiagnostic studies. In both cases causative anatomical structures were released through surgical exploration. A case was caused by a sharp edge of the flexor superficialis arcade, another case by the tendinous portion of deep head of pronator teres muscle and a thickened lacertus fibrosus. Both cases revealed partial recoveries after postoperative 3 months.

球狀黑鉛鑄鐵의 鹽浴窒化

張忠根,金水泳,李相益 충남대학교 자연과학연구소 1977 學術硏究誌 Vol.4 No.1

Liquid nitriding is being is used for machine parts to improve fatigue strength and resistance to wear and seizure in spheroidal graphite cist iron. The difference in matrixes with as cast, pesrlite or ferritic structure in the iron has an important effect on nitriding. in the present work, spheroidal graphite cast irons with different matrixes nitrided by the tufftride process at 570 C for 1-6 hrs for a bask study on the nitriding of spheroids1 graphite castiron. The relationship between maximun hardness and nitriding time can be obtained as follows. In ferritic matris, hardness of matrix increased from 250Hv for 6hrs of nitriding time. In pearlite matrix, hardness of matrix increased from 390Hv to 560Hv. for 6 hrs of nitrding time.

급성 간질성 신염과 동반된 신 실질 연반증

한인미,기연경,이은영,이충근,한승규,허수진,유태현 이화여자대학교 의과학연구소 2015 EMJ (Ewha medical journal) Vol.38 No.1

Malakoplakia is an uncommon chronic granulomatous inflammatory disease which is associated with immunocompromised conditions such as malignancy, autoimmune disease, chronic alcohol intake, poorly controlled diabetes and long-term steroid use. Malakoplakia can occur at various sites, most commonly in the genitourinary tract including urinary bladder and the ureter. Renal parenchymal involvement is relatively uncommon, accounting for 15% of all malakoplakia. A few cases of renal malakoplakia have been reported in Korea, and only one case was accompanied by acute kidney injury. Here we report an 80-year-old female patient with renal parenchymal malakoplakia and acute interstitial nephritis presented as acute kidney injury with literature review.

열공형과 비열공형 피질하 혈관성 치매에서 위험인자의 차이에 관한 비교 연구

배희준,정지향,유경호,나덕렬,김상윤,최경규,양동원,손의주,이상도,김재우,박경원,김응규,이재홍,박미영,한일우,함동석,최문성,하충건,최성혜,이애영,이병철,한설희 대한치매학회 2003 Dementia and Neurocognitive Disorders Vol.2 No.2

Backgrounds and Objectives: Vascular dementia is a group of dementing disoders arising from various stroke syndrome. Among these. subcortical ischemic vascular dementia (SIVD) is regarded as a relatively distinct clinical entity. However, MRI patterns of SIVD are not homogenous. In some patients, lacunes are dominant, and in others, subcortical white matter changes are. This study was designed to compare risk factor profiles between SIVD with and without multiple lacunes. Methods: We divided 47 subjects (22 males, mean age. 68 years) recruited from VADAPET (Multicenter Trial For Evaluation Of The Changes In the PET Images Of Subcortical Vascular Dementia Patient) study into two groups one with more than 5 lacunes in deep gray matter (lacune group) and the other with 5 or less(non-lacune group) Clinical characteristics and laboratory findings of two groups were compared. Results: Nineteen of 47 patients (40%) belonged to the lacune group. The lacune and non-lacune groups d d not differ in the following variables: age, hypertension, diabetes mellitus, hyperlipidemia heart disease, history of stroke or TIA, history of trauma or major surgery, family history of hypertension stroke, or dementia, age at diagnosis of dementia, body mass index, white blood cell count, ESR, CRP, fibrinogen, hemoglobin A1C, total cholesterol. LDL cholesterol creatinine, proteinuria, glucosuria, and microhematuria. However, male sex, smoking alcohol. hemoglobin, and HDL cholesterol were possibly associated more with lacune group SIVD than with non-lacune group (p<0 1) Multivariate analyses revealed that smoking, hemoglobin, and HDL cholesterol were independent predictors of SIVD with multiple lacunes Conclusion: Our study suggests that SIVD with multiple lacunes may be significantly different in smoking habits hemoglobin, and HDL cholesterol from SIVD without multiple lacunes.

Next-generation sequencing reveals novel resistance mechanisms and molecular heterogeneity in EGFR-mutant non-small cell lung cancer with acquired resistance to EGFR-TKIs

Lee, Choong-kun,Kim, Sora,Lee, Jae Seok,Lee, Jeong Eun,Kim, Sung-moo,Yang, In Seok,Kim, Hye Ryun,Lee, Jeong Ho,Kim, Sangwoo,Cho, Byoung Chul Elsevier 2017 Lung cancer Vol.113 No.-

<P><B>Abstract</B></P> <P><B>Objectives</B></P> <P>Despite initial responses to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) in EGFR mutant non-small cell lung cancer, patients invariably develop acquired resistance. In this study, we performed next-generation sequencing in pre- and post-EGFR-TKI tumor samples to identify novel resistance mechanisms to EGFR-TKIs.</P> <P><B>Material and methods</B></P> <P>We collected tumor tissues before EGFR-TKI treatment and after progression from 19 NSCLC patients to analyze genomic alterations in 409 cancer related genes. Bioinformatics analyses were used to identify mutations in which the allele frequencies are significantly changed, or newly appeared after progression.</P> <P><B>Results</B></P> <P>Overall, mutation rates and compositions were similar between pre- and post-EGFR-TKI tumors. We identified EGFR T790M as the most common mechanism of acquired resistance (63.2%). No pre-EGFR-TKI tumor had a preexisting T790M mutation, suggesting that tumors acquired T790M mutations following progression on EGFR-TKIs. Compared to T790M-positive tumors, T790M-negative tumors showed relatively high tumor mutation burden and shorter survival, suggesting T790M-negative patients as a potential candidate for immune checkpoint inhibitors. TP53 mutation was also significantly enriched in the T790M-negative tumors. Finally, we described here for the first time a novel missense mutation (T263P), which occurred concurrently with an activating G719A mutation, in the extracellular domain II of EGFR in a patient with poor response to erlotinib. Ba/F3 cells harboring EGFR T263P/G719A mutation showed higher sensitivity to afatinib, compared to gefitinib due to inhibition of EGFR/HER2 heterodimerization.</P> <P><B>Conclusion</B></P> <P>Comprehensive genomic analysis of post-EGFR-TKI tumors can provide novel insight into the complex molecular mechanisms of acquired resistance to EGFR-TKIs.</P> <P><B>Highlights</B></P> <P> <UL> <LI> NGS in paired NSCLC before and after EGFR-TKIs was performed. </LI> <LI> EGFR-TKI resistant T790M (+) NSCLC patients had significantly longer survival. </LI> <LI> Hypermutation/TP53 mutation seem enriched in EGFR-TKI resistant T790M (−) patients. </LI> <LI> Tumor mutation burden seem to be higher in EGFR-TKI resistant T790M (−) patients. </LI> <LI> T263P of EGFR was identified as the de novo mechanism of resistance to EGFR-TKIs. </LI> </UL> </P>

New Calculation of Charge Generation Efficiency and Photocurrent in Organic Photoconducting Device

Lee, Choong-Kun,Oh, Jin-Woo,Choi, Chil-Sung,Lee, Nam-Soo,Kim, Nak-Joong Korean Chemical Society 2009 Bulletin of the Korean Chemical Society Vol.30 No.1

A new approach was applied to examine the charge generation and transport in organic photoconductive devices by Monte‐Carlo simulation utilizing multiple site interactions of carriers with all other charges within Coulomb radius. Stepwise generation frame was considered first by a charge separation process that was counted in two separate transactions, i.e., hopping against physical decay and dissociation against recombination. Thereafter, diffusion/ drifting process of free carriers was counted to follow. This method enables to examine readily the photocurrent generated alongside the charge generation efficiency. The field and temperature dependences of the efficiency and photocurrent were obtained comparable to Onsager’s and experimental data.

Tumor metastasis to lymph nodes requires YAP-dependent metabolic adaptation

Lee, Choong-kun,Jeong, Seung-hwan,Jang, Cholsoon,Bae, Hosung,Kim, Yoo Hyung,Park, Intae,Kim, Sang Kyum,Koh, Gou Young American Association for the Advancement of Scienc 2019 Science Vol.363 No.6427

<P><B>Fueling lymph node metastases</B></P><P>Metastatic cells can migrate from a primary tumor to distant organs through two routes: They can enter the bloodstream directly, or they can enter a lymph node adjacent to the primary tumor. Little is known about the biological mechanisms that allow tumor cells to survive and grow within lymph nodes. Studying mouse models, Lee <I>et al.</I> found that tumor cells adapt to the lymph node microenvironment by shifting their metabolism toward fatty acid oxidation. This occurs through activation of a signaling pathway driven by the yes-associated protein (YAP) transcription factor. Importantly, inhibition of fatty acid oxidation or YAP signaling suppressed lymph node metastasis in the mice.</P><P><I>Science</I>, this issue p. 644</P><P>In cancer patients, metastasis of tumors to sentinel lymph nodes (LNs) predicts disease progression and often guides treatment decisions. The mechanisms underlying tumor LN metastasis are poorly understood. By using comparative transcriptomics and metabolomics analyses of primary and LN-metastatic tumors in mice, we found that LN metastasis requires that tumor cells undergo a metabolic shift toward fatty acid oxidation (FAO). Transcriptional coactivator yes-associated protein (YAP) is selectively activated in LN-metastatic tumors, leading to the up-regulation of genes in the FAO signaling pathway. Pharmacological inhibition of FAO or genetic ablation of YAP suppressed LN metastasis in mice. Several bioactive bile acids accumulated to high levels in the metastatic LNs, and these bile acids activated YAP in tumor cells, likely through the nuclear vitamin D receptor. Inhibition of FAO or YAP may merit exploration as a potential therapeutic strategy for mitigating tumor metastasis to LNs.</P>

Poster Session : PS 1438 ; Hemato-Oncology(Oncology) : Two Cases of Very Late Recurrence of Gastric Cancer Limited to Bone Marrow

( Choong Kun Lee ),( Su Jin Heo ),( Chang Gon Kim ),( Hyunki Kim ),( Sung Hoon Noh ),( Minkyu Jung ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

Background: Recurrence as bone marrow involvement is rare recur form in gastric cancer after gastrectomy, and very late recurrence of gastric cancer is even more rare. Herein we report two rare cases of very late recurrence of gastric cancer limited to bone marrow after curative gastrectomy. Case reports: A 54-year old female and a 62-year-old male presented with general weakness and poor oral intake. Both patients underwent curative gastrectomy 10 years ago, and postoperative surveillance was routinely done. Image study showed only skeletal metastasis (figure 1). Bone marrow aspiration and biopsy was done and pathology analysis revealed metastatic adenocarcinoma, suggesting gastric cancer recurrence (figure 2). Alkaline phosphatase (ALP) level was elevated for both cases. Both patients are currently on palliative chemotherapy. Conclusion: Bone marrow metastasis is a rare but possible mode of very late recurrence of gastric carcinoma. Watchful follow up is needed even after 10 years, especially among poorly differentiated or signet ring cell type. Serum ALP may serve as a sensitive marker.

The UGT1A9*22 genotype identifies a high-risk group for irinotecan toxicity among gastric cancer patients

Lee, Choong-kun,Chon, Hong Jae,Kwon, Woo Sun,Ban, Hyo-Jeong,Kim, Sang Cheol,Kim, Hyunwook,Jeung, Hei-Cheul,Chung, Jimyung,Rha, Sun Young Korea Genome Organization 2022 Genomics & informatics Vol.20 No.3

Several studies have shown associations between irinotecan toxicity and UGT1A genetic variations in colorectal and lung cancer, but only limited data are available for gastric cancer patients. We evaluated the frequencies of UGT1A polymorphisms and their relationship with clinicopathologic parameters in 382 Korean gastric cancer patients. Polymorphisms of UGT1A1*6, UGT1A1*27, UGT1A1*28, UGT1A1*60, UGT1A7*2, UGT1A7*3, and UGT1A9*22 were genotyped by direct sequencing. In 98 patients treated with irinotecan-containing regimens, toxicity and response were compared according to the genotype. The UGT1A1*6 and UGT1A9*22 genotypes showed a higher prevalence in Korean gastric cancer patients, while the prevalence of the UG1A1*28 polymorphism was lower than in normal Koreans, as has been found in other studies of Asian populations. The incidence of severe diarrhea after irinotecan-containing treatment was more common in patients with the UGT1A1*6, UGT1A7*3 and UGT1A9*22 polymorphisms than in controls. The presence of the UGT1A1*6 allele also showed a significant association with grade III-IV neutropenia. Upon haplotype and diplotype analyses, almost every patient bearing the UGT1A1*6 or UGT1A7*3 variant also had the UGT1A9*22 polymorphism, and all severe manifestations of UGT1A polymorphism-associated toxicity were related to the UGT1A9*22 polymorphism. By genotyping UGT1A9*22 polymorphisms, we could identify high-risk gastric cancer patients receiving irinotecan-containing chemotherapy, who would experience severe toxicity. When treating high-risk patients with the UGT1A9*22 polymorphism, clinicians should closely monitor them for signs of toxicity such as severe diarrhea or neutropenia.