• Journal of Chest Surgery
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• v.42 no.4
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• pp.543-559
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• 2009

Dr Lillehei (1918$\sim$1999) pioneered cardiac surgery with his landmark operations using cross-circulation in 1954 and 1955. With his dedications to open heart surgery, he is generally considered to be the father of open heart surgery by many medical historians. Dr Lillehei expanded his contributions to cardiac surgery with training 134 cardiothoracic surgeons at the University of Minnesota Hospital and he trained an additional 20 surgeons at the Cornell Medical Center. Dr Lillehei's trainees came from all over the world and Dr YK lee (1921$\sim$1994) of Seoul National University was among them. He joined the University of Minnesota Hospital in 1957 as a part of the Minnesota project. During his stay for two years, in addition to experimental research, he learned clinical cardiac surgery as part of Dr Lillehei's team. In 1959, after returning to Korea, Dr Lee began his career as. a full-time cardiac surgeon with establishing the Division of Cardiac Surgery at Seoul National University. Hospital. Yet he encountered many difficult barriers in the process. During that time, Dr Lillehei was willing to share his experience and he provided many valuable resources for cardiac operations. With Dr Lillehei's kind help, the open heart surgery program was gradually and successfully established at Seoul National University Hospital. These two surgical titans from across the Pacific Ocean died in 1994 (Dr Lee) and 1999 (Dr Lillehei). They are gone, yet the proud Korean people have not forgotten them.

• Journal of Periodontal and Implant Science
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• v.53 no.1
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• pp.54-68
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• 2023

Purpose: The purpose of this study was to determine whether metformin (MF) could alleviate the expresssion of reactive oxygen species (ROS) and improve the osteogenic ability of bone marrow mesenchymal stem cells derived from diabetic rats (drBMSCs) in vitro, and to evaluate the effect of MF on the ectopic osteogenesis of drBMSCs in a nude mouse model in vivo. Methods: BMSCs were extracted from normal and diabetic rats. In vitro, a cell viability assay (Cell Counting Kit-8), tests of alkaline phosphatase (ALP) activity, and western blot analysis were first used to determine the cell proliferation and osteogenic differentiation of drBMSCs that were subjected to treatment with different concentrations of MF (0, 50, 100, 200, 500 µM). The cells were then divided into 5 groups: (1) normal rat BMSCs (the BMSCs derived from normal rats group), (2) the drBMSCs group, (3) the drBMSCs + Mito-TEMPO (10 µM, ROS scavenger) group, (4) the drBMSCs + MF (200 µM) group, and (5) the drBMSCs + MF (200 µM) + H₂O₂ (50 µM, ROS activator) group. Intracellular ROS detection, a senescence-associated β-galactosidase assay, ALP staining, alizarin red staining, western blotting, and immunofluorescence assays were performed to determine the effects of MF on oxidative stress and osteogenic differentiation in drBMSCs. In vivo, the effect of MF on the ectopic osteogenesis of drBMSCs was evaluated in a nude mouse model. Results: MF effectively reduced ROS levels in drBMSCs. The cell proliferation, ALP activity, mineral deposition, and osteogenic-related protein expression of drBMSCs were demonstrably higher in the MF-treated group than in the non-MF-treated group. H₂O₂ inhibited the effects of MF. In addition, ectopic osteogenesis was significantly increased in drBMSCs treated with MF. Conclusions: MF promoted the proliferation and osteogenic differentiation of drBMSCs by inhibiting the oxidative stress induced by diabetes and enhenced the ectopic bone formation of drBMSCs in nude mice.

• The Korea Journal of Herbology
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• v.24 no.4
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• pp.189-195
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• 2009

Objectives : In this study, the effect of Dipsaci Radix(DR, Dipsacus asperoides C.Y. Cheng et T. M. Ai) water extract on LPS-induced inflammatory response in RAW264.7 cells were investigated. Methods : Dried roots of DR was extracted with water for 3 h(DR-W extract). RAW264.7 cells, a mouse macrophage line, were incubated with different concentrations of DR-W extract for 30 min and then stimulated with LPS at indicated times. Cell toxicity was determined by MTT assay. The concentrations of nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) were measured by Griess assay and enzyme immunoassay (EIA), respectively. The expression of inducible nitric oxide synthease (iNOS) and cyclooxyganase (COX)-2 mRNA and protein was determined by RT-PCR and Western blot, respectively. Results : DR-W extract was significantly inhibited LPS-induced productions of NO and PGE2 in RAW264.7 cells. DR-W extract was not suppressed the expressions of iNOS mRNA and protein in LPS-stimulated RAW264.7 cells. Conclusions : This study suggests that DR-W extract can attenuate inflammatory response via inhibition of the NO and PGE2 production in activated macrophages.

• Journal of the Korean Chemical Society
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• v.55 no.5
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• pp.760-764
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• 2011

A new series of 1-(5-(2-tolyloxyquinoline-3-yl)-2-(pyridine-4-yl)-1,3,4-oxidiazol-3(2H)-yl)ethanones were synthesized from cyclisation of N'-((2-(p-tolyloxy)quinoline-3-yl)methylene) isonitonohydrazide in acetic unhydride at reflux condition for 3-4 hr. The structures of the new compounds were confirmed by elemental analyses as well as IR, 1H NMR and mass spectral data. All the synthesized compounds were screened for their antibacterial activities against various bacterial strains. Several of these compounds showed potential antibacterial activity.

• Journal of the Korean Chemical Society
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• v.54 no.5
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• pp.582-588
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• 2010

The synthesis of benzofuran based 1,3,4-thiadiazoles, 1,3,4-triazoles and 1,3,4-oxadiazole via cyclocondensation of thiosemicarbazides have been carried out by conventional and non-conventional methods in excellent yields of product.

• Journal of the Korean Chemical Society
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• v.55 no.5
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• pp.805-807
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• 2011

The synthesis of different derivatives of isoxazolo[5,4-b]quinoline by the cyclization reaction of various substituted oximes of quinoline using mild base at ambient temperature. The formation of isoxazolo[5,4-b]quinoline, as a consequence of cheaper and more readily available $K_2CO_3$ and DMF participating in the reaction, is documented.

• Journal of Microbiology and Biotechnology
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• v.32 no.5
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• pp.575-581
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• 2022

A Gram-stain-negative, white-coloured, and rod-shaped bacterium, strain DR4-4^T, was isolated from Daechung Reservoir, Republic of Korea, during Microcystis bloom. Strain DR4-4^T was most closely related to Caenimonas terrae SGM1-15^T and Caenimonas koreensis EMB320^T with 98.1% 16S rRNA gene sequence similarities. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain DR4-4^T and closely related type strains were below 79.46% and 22.30%, respectively. The genomic DNA G+C content was 67.5%. The major cellular fatty acids (≥10% of the total) were identified as C_16:0, cyclo C_17:0, summed feature 3 (C_16:1ω7c and/or C_16:1ω6c), and summed feature 8 (C_18:1ω7c and/or C_18:1ω6c). Strain DR4-4^T possessed phosphatidylethanolamine, diphosphatidylglycerol, and phosphatidylglycerol as the main polar lipids and Q-8 as the respiratory quinone. The polyamine profile was composed of putrescine, cadaverine, and spermidine. The results of polyphasic characterization indicated that the isolated strain DR4-4^T represents a novel species within the genus Caenimonas, for which the name Caenimonas aquaedulcis sp. nov. is proposed. The type strain is DR4-4^T (=KCTC 82470^T =JCM 34453^T).

• Journal of radiological science and technology
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• v.26 no.3
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• pp.7-11
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• 2003

Currently, many hospitals are hastening to introduce digital radiography systems. This is a direct result of the intentions to improve medical services and to digitalize radiology information systems, and is also leading to the improvement of medical imaging technology. Throughout F/S system's long history, many people have researched the image quality and dosage concerning these systems, and as a result, huge improvements in the dosage of patients were possible. Similarly, I believe that DR systems need the same kind of effort. Of course, decreases in dosage that ignore image quality are unthinkable. The results of experiments conducted by five hospitals during a period of 3 months brought to us the conclusions listed below. 1. Based on the comparison and analysis of the exposure control of F/S systems and DR systems, DR systems generally showed higher exposure control for parts of the phantom that became thicker, and the exposure control improved rapidly as the thickness increased. 2. DR systems still proved to be somewhat deficient in resolution measurements compared to existing F/S systems. The image processing part of DR systems contributed much to these result. 3. Under conditions used clinically, the dosage measurements of DR systems were generally higher regardless of region. 4. According to the evaluation of image quality, DR systems showed a higher degree of satisfaction as the thickness of the region became thinner. As mentioned above and based on the mutual relationship experiments between the dosage and image quality of F/S systems and DR systems, research to increase the satisfaction of DR systems must be considered.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.24
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• pp.10697-10703
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• 2015

The laryngeal squamous cell carcinoma (LSCC) is one of the most common malignant tumors occurring in the head and neck. Tumor necrosis factor related apoptosis induce ligand (TRAIL) and TRAIL-receptors (DR4, DR5, DcR1, DcR2) are known as important members of TRAIL-mediated biochemical signaling pathway. Associations between polymorphisms in these genes and clinicopathological characteristics of human laryngeal carcinoma are not well defined. This study therefore aimed to investigate a possible relationship among the TRAIL and TRAIL-DR4 polymorphisms and sTRAIL levels in the risk or progression of LSCC. A total of 99 patients with laryngeal cancer and 120 healthy subjects were enrolled in the study. DR4 C626G and TRAIL 1595 C/T genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis and sTRAIL levels were measured by ELISA. There were significant differences in the distribution of DR4 C626G genotypes and frequencies of the alleles between laryngeal cancer patients and controls (p<0.001) but not in TRAIL 1595 C/T. We found the increased frequency of the DR4 C626G homozygote CC genotype in patients than in controls (p<0.001). Haplotype analysis revealed that there was also a statistically significant relationship between TRAIL and TRAIL-DR4 polymorphisms and laryngeal cancer. Serum sTRAIL levels in the laryngeal patients with CC genotype who had advanced tumour stage were lower than those of patients with early tumor stage (p=0.014). Our findings suggest that DR4 C626G genotypes and sTRAIL levels might be associated with progression of laryngeal cancer in the Turkish population.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.4
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• pp.1371-1374
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• 2015

Background: Tongue cancer is one of the leading sites of cancer in our population. Aim: To evaluate the socio-demographic profiles and stages at diagnosis of oral tongue (OT) and base of tongue (BT) cancers, and identify any possible variations in characteristics. Materials and Methods: A retrospective analysis was conducted on tongue cancer cases, divided into OT and BT, registered at the hospital cancer registry of North-East India during January 2010 to May 2013. Cases were analyzed for age, gender, residential status and different levels of education for patients, the stage at diagnosis and presence of distant metastasis. Results: A total of 1,113 cases of tongue cancers were registered, 846(76.1%) of BT and 267(23.9%) of OT. While 33.9% of BT cancer patients were above 65 years of age, the figure for OT cancers was 18.4%, stages III and IV accounting for 90.8% and 77%, respectively. The relative risk for distant metastasis in OT cancers was 3.3 (95% CI 1.08-10.1, p=0.03). Conclusions: In the subsites of tongue cancers in our population, the majority arose from the base of tongue, these tending to occur in older individuals and presenting at late stage.