1.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*
2.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*
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.Noninvasive fetal RHD genotyping using cell-free fetal DNA incorporating fetal RASSF1A marker in RhD-negative pregnant women in Korea.
Sung Hee HAN ; Young Ho YANG ; Jae Song RYU ; Young Jin KIM ; Kyoung Ryul LEE
Journal of Genetic Medicine 2015;12(2):100-108
PURPOSE: Conventional methods for the prenatal detection of fetal RhD status involve invasive procedures such as fetal blood sampling and amniocentesis. The identification of cell-free fetal DNA (cffDNA) in maternal plasma creates the possibility of determining fetal RhD status by analyzing maternal plasma DNA. However, some technical problems still exist, especially the lack of a positive control marker for the presence of fetal DNA. Therefore, we assessed the feasibility and accuracy of fetal RHD genotyping incorporating the RASSF1A epigenetic fetal DNA marker from cffDNA in the maternal plasma of RhD-negative pregnant women in Korea. MATERIALS AND METHODS: We analyzed maternal plasma from 41 pregnant women identified as RhD-negative by serological testing. Multiplex real-time PCR was performed by amplifying RHD exons 5 and 7 and the SRY gene, with RASSF1A being used as a gender-independent fetal epigenetic marker. The results were compared with those obtained by postnatal serological analysis of cord blood and gender identification. RESULTS: Among the 41 fetuses, 37 were RhD-positive and 4 were RhD-negative according to the serological analysis of cord blood. There was 100% concordance between fetal RHD genotyping and serological cord blood results. Detection of the RASSF1A gene verified the presence of cffDNA, and the fetal SRY status was correctly detected in all 41 cases. CONCLUSION: Noninvasive fetal RHD genotyping with cffDNA incorporating RASSF1A is a feasible, reliable, and accurate method of determining fetal RhD status. It is an alternative to amniocentesis for the management of RhD-negative women and reduces the need for unnecessary RhIG prophylaxis.
Amniocentesis
;
DNA*
;
Epigenomics
;
Exons
;
Female
;
Fetal Blood
;
Fetus
;
Genes, sry
;
Genetic Markers
;
Humans
;
Korea*
;
Plasma
;
Pregnant Women*
;
Prenatal Diagnosis
;
Real-Time Polymerase Chain Reaction
;
Serologic Tests
9.Noninvasive prenatal test for fetal chromosomal aneuploidies by massively parallel sequencing of cell-free fetal DNA in maternal plasma: The first clinical experience in Korea.
Sung Hee HAN ; Young Ho YANG ; Jae Song RYU ; Myung Soo KANG ; Young Jin KIM ; Kyoung Ryul LEE
Journal of Genetic Medicine 2015;12(2):85-91
PURPOSE: Noninvasive prenatal test (NIPT) by massively parallel sequencing (MPS) of cell-free fetal DNA in maternal plasma marks a significant advancement in prenatal screening, minimizing the need for invasive testing of fetal chromosomal aneuploidies. Here, we report the initial clinical performance of NIPT in Korean pregnant women. MATERIALS AND METHODS: MPS-based NIPT was performed on 910 cases; 5 mL blood samples were collected and sequenced in the Shenzhen BGI Genomic Laboratory to identify aneuploidies. The risk of fetal aneuploidy was determined by L-score and t-score, and classified as high or low. The NIPT results were validated by karyotyping for the high-risk cases and neonatal follow-up for low-risk cases. RESULTS: NIPT was mainly requested for two clinical indications: abnormal biochemical serum-screening result (54.3%) and advanced maternal age (31.4%). Among 494 cases with abnormal biochemical serum-screening results, NIPT detected only 9 (1.8%) high-risk cases. Sixteen cases (1.8%) of 910 had a high risk for aneuploidy: 8 for trisomy 21, 2 for trisomy 18, 1 for trisomy 13, and 5 for sex chromosome abnormalities. Amniocentesis was performed for 7 of these cases (43.8%). In the karyotyping and neonatal data, no false positive or negative results were observed in our study. CONCLUSION: MPS-based NIPT detects fetal chromosomal aneuploidies with high accuracy. Introduction of NIPT as into clinical settings could prevent about 98% of unnecessary invasive diagnostic procedures.
Amniocentesis
;
Aneuploidy*
;
DNA*
;
Down Syndrome
;
Female
;
Follow-Up Studies
;
High-Throughput Nucleotide Sequencing*
;
Humans
;
Karyotyping
;
Korea*
;
Maternal Age
;
Plasma*
;
Pregnant Women
;
Prenatal Diagnosis
;
Sex Chromosome Aberrations
;
Trisomy
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