1.Cabrol operation with cabrol trick in annulo-aortic ectasia.
Sam Ryul RYU ; Pill Jo CHOI ; Si Chan SUNG ; Si Young HAM ; Jong Su WOO
The Korean Journal of Thoracic and Cardiovascular Surgery 1992;25(10):1152-1156
No abstract available.
Dilatation, Pathologic*
2.Descending necrotizing mediastinitis: a case report.
Sam Ryul RYU ; Byung Woo BAE ; Si Chan SUNG ; Hwang Kiw CHUNG
The Korean Journal of Thoracic and Cardiovascular Surgery 1991;24(12):1228-1231
No abstract available.
Mediastinitis*
3.Esophageal reconstruction with isoperistaltic interposition of left colon.
Si Chan SUNG ; Si Young HAM ; Jong Su WOO ; Sam Ryul RYU ; Hwang Kiw CHUNG ; Soo Keun WANG
The Korean Journal of Thoracic and Cardiovascular Surgery 1991;24(9):895-902
No abstract available.
Colon*
4.Enhancement of beta-Glucan Content in the Cultivation of Cauliflower Mushroom (Sparassis latifolia) by Elicitation.
Hyun PARK ; Kang Hyeon KA ; Sung Ryul RYU
Mycobiology 2014;42(1):41-45
The effectiveness of three kinds of enzymes (chitinase, beta-glucuronidase, and lysing enzyme complex), employed as elicitors to enhance the beta-glucan content in the sawdust-based cultivation of cauliflower mushroom (Sparassis latifolia), was examined. The elicitors were applied to the cauliflower mushroom after primordium formation, by spraying the enzyme solutions at three different levels on the sawdust-based medium. Mycelial growth was fully accomplished by the treatments, but the metabolic process during the growth of fruiting bodies was affected. The application of a lysing enzyme resulted in an increase in the beta-glucan concentration by up to 31% compared to that of the control. However, the treatment resulted in a decrease in mushroom yield, which necessitated the need to evaluate its economic efficiency. Although we still need to develop a more efficient way for using elicitors to enhance functional metabolites in mushroom cultivation, the results indicate that the elicitation technique can be applied in the cultivation of medicinal/edible mushrooms.
Agaricales*
;
Brassica*
;
Fruit
;
Glucuronidase
;
Metabolism
5.Urinary Levels of Arsenic, Cadmium, and Zinc of Children in Ulsan Industrial Area.
Choong Ryeol LEE ; Cheol In RYU ; Ji Ho LEE ; Sung Ryul KIM ; Jin Young JEONG
Korean Journal of Preventive Medicine 1999;32(1):1-8
OBJECTIVES: We conducted this study to obtain basic data of urinary levels of arsenic, cadmium, and zinc in children of Ulsan industrial area and to evaluate the difference in urinary levels of these metals between industrial area and suburban area. METHODS: The study subjects were composed of 348(male 182, female 166) school children residing in industrial area and 100(male 50, female 50) school children of suburban area. We analyzed urinary levels of arsenic, cadmium, and zinc using atomic absorption spectrophotometer. RESULTS: The geometric means of urinary levels of arsenic, cadmium, and zinc of study participants were 3.69, 0.99, 282.49 microgram/L respectively. The adjusted geometric means of urinary levels of arsenic, cadmium, and zinc of study participants were 3.92, 1.05, 299.92 microgram/g creatinine respectively. CONCLUSIONS: The children residing in industrial area had the higher urinary levels of arsenic and cadmium than suburban children with statistical significance(p<0.01).
Absorption
;
Arsenic*
;
Cadmium*
;
Child*
;
Creatinine
;
Female
;
Humans
;
Metals
;
Ulsan*
;
Zinc*
6.Implantable Neural Probes for Brain-Machine Interfaces – Current Developments and Future Prospects.
Jong ryul CHOI ; Seong Min KIM ; Rae Hyung RYU ; Sung Phil KIM ; Jeong woo SOHN
Experimental Neurobiology 2018;27(6):453-471
A Brain-Machine interface (BMI) allows for direct communication between the brain and machines. Neural probes for recording neural signals are among the essential components of a BMI system. In this report, we review research regarding implantable neural probes and their applications to BMIs. We first discuss conventional neural probes such as the tetrode, Utah array, Michigan probe, and electroencephalography (ECoG), following which we cover advancements in next-generation neural probes. These next-generation probes are associated with improvements in electrical properties, mechanical durability, biocompatibility, and offer a high degree of freedom in practical settings. Specifically, we focus on three key topics: (1) novel implantable neural probes that decrease the level of invasiveness without sacrificing performance, (2) multi-modal neural probes that measure both electrical and optical signals, (3) and neural probes developed using advanced materials. Because safety and precision are critical for practical applications of BMI systems, future studies should aim to enhance these properties when developing next-generation neural probes.
Brain
;
Brain-Computer Interfaces*
;
Electroencephalography
;
Freedom
;
Michigan
;
Utah
7.Gastrointestinal Stromal Tumor (GIST) of the Stomach: Clinicopathologic Analysis and Outcome.
Je Seock RYU ; Sung Ryul LEE ; Sae Byeol CHOI ; Sung Soo PARK ; Ju Han LEE ; Seung Joo KIM ; Chong Suk KIM ; Yang Seok CHAE ; Young Jae MOK
Journal of the Korean Gastric Cancer Association 2005;5(1):40-46
PURPOSE: Gastrointestinal stromal tumors (GISTs) are mesenchymal neoplasms of the gastrointestinal tract. GISTs are positive for the expression of c-Kit protein at immunohistochemistry, and their clinical presentations vary. This retrospective study was performed to evaluate the clincopathologic characteristics of GISTs and to define the prognostic factors. MATERIALS AND METHODS: 40 patients who underwent a complete resection of a GIST during the period 1996~2003 at the Department of Surgery, Korea University College of Medicine, were studied. We divided them into low- and high-risk groups by using tumor size and mitotic count: 23 cases were low risk, and 17 were high risk. Clinicopathologic features, immunohistochemical findings, and prognoses were compared between the low- and the high-risk groups. RESULTS: The mean age of the 40 patients was 61.3+/-11.1 years, and the male-to-female ratio was 1:1.1. There was no significant difference in age and sex between the groups. A comparative analysis revealed tumor size, mitotic count, clinical symptoms, preoperative pathologic diagnosis, ulceration, and necrosis to be variables that had statistically significant differences between the high- and the low-risk groups. In the univariate analysis, tumor size, mitotic count, ulceration, necrosis, and abnormal endoscopic ultrasound findings were associated with disease-free survival, but in the multivariate analysis, mitotic activity was the only independent factor associated with disease-free survival. 8 patients had recurrences during the follow-up period, and four of them were treated with STI-571 (imatinib mesylate, Gleevec(R)). The treated patients have survived until now; however, two of non-treated patients died from disease progression. CONCLUSION: Based on this study, tumor size, ulceration, and necrosis are significant factors affecting survival, and mitotic activity may be a useful prognostic marker. STI-571 may be used in an adjuvant setting because the drug has shown anticancer activity in patients with recurrence or metastasis.
Diagnosis
;
Disease Progression
;
Disease-Free Survival
;
Follow-Up Studies
;
Gastrointestinal Stromal Tumors*
;
Gastrointestinal Tract
;
Humans
;
Immunohistochemistry
;
Korea
;
Mesylates
;
Multivariate Analysis
;
Necrosis
;
Neoplasm Metastasis
;
Prognosis
;
Proto-Oncogene Proteins c-kit
;
Recurrence
;
Retrospective Studies
;
Stomach*
;
Ulcer
;
Ultrasonography
;
Imatinib Mesylate
8.Validation of QF-PCR for Rapid Prenatal Diagnosis of Common Chromosomal Aneuploidies in Korea.
Sung Hee HAN ; Jae Song RYU ; Jeong Wook AN ; Ok Kyoung PARK ; Hye Ryoung YOON ; Young Ho YANG ; Kyoung Ryul LEE
Journal of Genetic Medicine 2010;7(1):59-66
PURPOSE: Quantitative fluorescent polymerase chain reaction (QF-PCR) allows for the rapid prenatal diagnosis of common aneuploidies. The main advantages of this assay are its low cost, speed, and automation, allowing for large-scale application. However, despite these advantages, it is not a routine method for prenatal aneuploidy screening in Korea. Our objective in the present study was to validate the performance of QF-PCR using short tandem repeat (STR) markers in a Korean population as a means for rapid prenatal diagnosis. MATERIALS AND METHODS: A QF-PCR assay using an Elucigene kit (Gen-Probe, Abingdon, UK), containing 20 STR markers located on chromosomes 13, 18, 21, X and Y, was performed on 847 amniotic fluid (AF) samples for prenatal aneuploidy screening referred for prenatal aneuploidy screening from 2007 to 2009. The results were then compared to those obtained using conventional cytogenetic analysis. To evaluate the informativity of STR markers, the heterozygosity index of each marker was determined in all the samples. RESULTS: Three autosomes (13, 18, and 21) and X and Y chromosome aneuploidies were detected in 19 cases (2.2%, 19/847) after QF-PCR analysis of the 847 AF samples. Their results are identical to those of conventional cytogenetic analysis, with 100% positive predictive value. However, after cytogenetic analysis, 7 cases (0.8%, 7/847) were found to have 5 balanced and 2 unbalanced chromosomal abnormalities that were not detected by QF-PCR. The STR markers had a slightly low heterozygosity index (average: 0.76) compared to those reported in Caucasians (average: 0.80). Submicroscopic duplication of D13S634 marker, which might be a unique finding in Koreans, was detected in 1.4% (12/847) of the samples in the present study. CONCLUSION: A QF-PCR assay for prenatal aneuploidy screening was validated in our institution and proved to be efficient and reliable. However, we suggest that each laboratory must perform an independent validation test for each STR marker in order to develop interpretation guidelines of the results and must integrate QF-PCR into the routine cytogenetic laboratory workflow.
Amniotic Fluid
;
Aneuploidy
;
Automation
;
Chromosome Aberrations
;
Cytogenetic Analysis
;
Cytogenetics
;
Female
;
Korea
;
Mass Screening
;
Microsatellite Repeats
;
Polymerase Chain Reaction
;
Prenatal Diagnosis
;
Y Chromosome
9.Transdifferentiation of Enteroendocrine K-cells into Insulin-expressing Cells.
Esder LEE ; Jun Mo YU ; Min Kyung LEE ; Gyeong Ryul RYU ; Seung Hyun KO ; Yu Bae AHN ; Sung Dae MOON ; Ki Ho SONG
Korean Diabetes Journal 2009;33(6):475-484
BACKGROUND: Despite a recent breakthough in human islet transplantation for treating type 1 diabetes mellitus, the limited availability of donor pancreases remains a major obstacle. Endocrine cells within the gut epithelium (enteroendocrine cells) and pancreatic beta cells share similar pathways of differentiation during embryonic development. In particular, K-cells that secrete glucose-dependent insulinotropic polypeptide (GIP) have been shown to express many of the key proteins found in beta cells. Therefore, we hypothesize that K-cells can be transdifferentiated into beta cells because both cells have remarkable similarities in their embryonic development and cellular phenotypes. METHODS: K-cells were purified from heterogeneous STC-1 cells originating from an endocrine tumor of a mouse intestine. In addition, a K-cell subclone expressing stable Nkx6.1, called "Kn4-cells," was successfully obtained. In vitro differentiation of K-cells or Kn4-cells into beta cells was completed after exendin-4 treatment and serum deprivation. The expressions of insulin mRNA and protein were examined by RT-PCR and immunocytochemistry. The interacellular insulin content was also measured. RESULTS: K-cells were found to express glucokinase and GIP as assessed by RT-PCR and Western blot analysis. RT-PCR showed that K-cells also expressed Pdx-1, NeuroD1/Beta2, and MafA, but not Nkx6.1. After exendin-4 treatment and serum deprivation, insulin mRNA and insulin or C-peptide were clearly detected in Kn4-cells. The intracellular insulin content was also increased significantly in these cells. CONCLUSION: K-cells are an attractive potential source of insulin-producing cells for treatment of type 1 diabetes mellitus. However, more experiments are necessary to optimize a strategy for converting K-cells into beta cells.
Animals
;
Blotting, Western
;
C-Peptide
;
Diabetes Mellitus, Type 1
;
Embryonic Development
;
Endocrine Cells
;
Enteroendocrine Cells
;
Epithelium
;
Female
;
Glucokinase
;
Humans
;
Immunohistochemistry
;
Insulin
;
Insulin-Secreting Cells
;
Intestines
;
Islets of Langerhans Transplantation
;
Mice
;
Pancreas
;
Peptides
;
Phenotype
;
Pregnancy
;
Proteins
;
RNA, Messenger
;
Tissue Donors
;
Venoms
10.Altered Cholecystokinin-induced Calcium Signal in Streptozotocin-induced Diabetic Rat Pancreatic Acini.
Myung Jun KIM ; Gyeong Ryul RYU ; Jong Ho SUNG ; Do Sik MIN ; Duck Joo RHIE ; Shin Hee YOON ; Sang June HAHN ; Yang Hyeok JO ; Myung Suk KIM
The Korean Journal of Gastroenterology 2003;42(6):519-526
BACKGROUND/AIMS: Pancreatic acini of streptozotocin (STZ)-induced diabetic rats release amylase less than normal acini on cholecystokinin (CCK) stimulation. Pancreatic enzyme secretion has been closely related to the intracellular calcium concentration ([Ca2+]i) of the acinar cell. In the present study, sequential changes of the intracellular calcium signal which probably underlie the altered enzyme secretion in response to CCK-8 were investigated using pancreatic acini from diabetic rats. METHODS: Diabetic rats were prepared by single intravenous injection of STZ (70 mg/kg). Stimulating experiments with CCK-8 were performed 7 days later. Pancreatic acini were isolated by collagenase digestion. Amylase release and [Ca2+]i were measured by colorimethod and calcium imaging, respectively. The geometry of intracellular calcium signal was analyzed. RESULTS: Normal acini exhibited concentration-dependent [Ca2+]i increase and regular oscillatory calcium signal on CCK-8 stimulation. Amylase release was also concentration-dependent. However, diabetic acini showed significantly less [Ca2+]i increase, prolonged time to peak [Ca2+]i, decreased calcium spikes number, and decreased amylase release compared with normal acini. The decreased [Ca2+]i in diabetic acini was restored significantly by insulin treatment. CONCLUSIONS: Relatively decreased amylase release in diabetic pancreatic acini in response to CCK, appears to be associated with altered calcium signal due to insulin deficiency.
Amylases/*secretion
;
Animals
;
Calcium Signaling/*drug effects
;
Diabetes Mellitus, Experimental/*physiopathology
;
Pancreas/cytology/metabolism/*secretion
;
Rats
;
Rats, Sprague-Dawley
;
Sincalide/*pharmacology