1.Influence of Physicochemical Environmental Factors on the Occurrence of Waterborne Viruses in Korean Surface Water.
Gyucheol LEE ; Younsuk JEE ; Chanhee LEE ; Sangtae LEE
Journal of Bacteriology and Virology 2006;36(4):279-285
In order to survey the occurrence of waterborne viruses in Korean surface water, a total of 192 water samples from July 2003 to January 2006 were collected and analyzed. The presence of waterborne viruses was investigated by total culturable virus assay (TCVA) using buffalo green monkey kidney (BGMK) cells. The results showed that 63 of 192 samples (32.8%) were positive for waterborne viruses with the average concentration of 3.1+/-18 most probable numbers (MPN)/100 L. The relationship between the occurrence of the viruses and the physicochemical environmental factors revealed that there was a significant correlation between the turbidity of water and the occurrence of the viruses. It was also noted that the water temperature might have some relationship with the occurrence of the viruses, as the frequency of the viruses was higher in low temperature or winter season. Therefore, the occurrence of waterborne viruses in Korean surface water might be affected by the physicochemical environmental factors such as turbidity and water temperature.
Buffaloes
;
Cercopithecus aethiops
;
Kidney
;
Seasons
;
Water*
2.Antimalarial Activity of C-10 Substituted Triazolyl Artemisinin.
Gab Man PARK ; Hyun PARK ; Sangtae OH ; Seokjoon LEE
The Korean Journal of Parasitology 2017;55(6):661-665
We synthesized C-10 substituted triazolyl artemisinins by the Huisgen cycloaddition reaction between dihydroartemisinins (2) and variously substituted 1, 2, 3-triazoles (8a-8h). The antimalarial activities of 32 novel artemisinin derivatives were screened against a chloroquine-resistant parasite. Among them, triazolyl artemisinins with electron-withdrawing groups showed stronger antimalarial activities than those shown by the derivatives having electron-donating groups. In particularly, m-chlorotriazolyl artemisinin (9d-12d) showed antimalarial activity equivalent to that of artemisinin and could be a strong drug candidate.
Artemisinins
;
Cycloaddition Reaction
;
Parasites
3.Development of in vitro produced porcine embryos according to serum types as macromolecule.
Jungmin SON ; Don Buddika Oshadi MALAWEERA ; Eunsong LEE ; Sangtae SHIN ; Jongki CHO
Journal of Veterinary Science 2013;14(3):315-321
This study was conducted to establish an in vitro maturation (IVM) system by selection of efficient porcine serum during porcine in vitro production. To investigate the efficient porcine serum (PS), different types of PS [newborn pig serum, prepubertal gilt serum (PGS), estrus sow serum, and pregnancy sow serum] were used to supplement IVM media with or without gonadotrophin (GTH) and development rates of parthenogenetic activation (PA) and in vitro fertilization (IVF) embryos were then compared. The maturation rates of the PGS group was significantly higher when GTH was not added. Additionally, during development of PA embryos without GTH, the PGS group showed significantly higher cleavage and blastocyst formation rates. Moreover, the cleavage rates of IVF embryos were significantly higher in the PGS group, with no significant differences in the blastocyst formation. However, when GTH was supplemented into the IVM media, there were no significant differences among the four groups in the cleavage rates, development rates of the blastocyst, and cell number of the blastocyst after PA and IVF. In conclusion, PGS is an efficient macromolecule in porcine IVM, and GTH supplementation of the IVM media is beneficial when PS is used as macromolecule, regardless of its origin.
Animals
;
Blastocyst/*drug effects
;
Embryo, Mammalian/drug effects/*embryology/physiology/ultrastructure
;
Fertilization in Vitro/veterinary
;
Gonadotropins/administration & dosage/*metabolism
;
In Vitro Oocyte Maturation Techniques/*methods/veterinary
;
Parthenogenesis/*drug effects
;
Sus scrofa/*embryology
4.Inflammation and tissue remodeling contribute to fibrogenesis in stricturing Crohn’s disease: image processing and analysis study
Mustafa Erdem ARSLAN ; Rupinder BRAR ; Lianna GOETZ ; Dipti KARAMCHANDANI ; Michael W. MIKULA ; Kyle HODGE ; Hua LI ; Sangtae AHN ; Hwajeong LEE
Journal of Pathology and Translational Medicine 2022;56(5):239-248
Background:
Inflammation and structural remodeling may contribute to fibrogenesis in Crohn’s disease (CD). We quantified the immunoexpression of calretinin, CD34, and calprotectin as a surrogate for mucosal innervation, telocytes (interstitial cells playing a role in networking), and inflammation, respectively, and correlated them with bowel alterations in stricturing CD.
Methods:
Primary resection specimens for ileal CD (n = 44, 31 stricturing CD, 13 inflammatory CD) were identified. Left-sided ulcerative colitis and trauma cases were used as controls. Proximal and distal margin and middle (diseased) sections were stained for calretinin, CD34, and calprotectin. Microscopic images were captured from the mucosa (calretinin), submucosa (calprotectin), and myenteric plexus (CD34), and the immunostaining was quantified using image processing and analysis. Bowel thickness at the corresponding sections were measured and correlated with the amount of immunoexpression.
Results:
A total of 2,037 images were analyzed. In stricturing CD, submucosal alteration/thickening at the stricture site correlated with calprotectin staining and inversely correlated with calretinin staining at the proximal margin. Muscularis propria alteration/thickening at the stricture site correlated with mucosal calretinin staining at the proximal margin. Submucosal alteration/thickening at the proximal margin correlated with calretinin and CD34 staining at the proximal margin and inversely correlated with CD34 staining at the stricture site. Calretinin immunostaining at the distal margin was significantly higher in stricturing CD than the controls.
Conclusions
Inflammation and tissue remodeling appear to contribute to fibrogenesis in stricturing CD. Increased mucosal calretinin immunostaining distal to the diseased segment could be helpful in diagnosing CD in the right clinical context.
5.Reduced fasting time in patients who underwent totally laparoscopic distal gastrectomy
Sangtae JANG ; Ayoung KANG ; Hong-min AHN ; Sun-Hwi HWANG ; Si-Hak LEE
Annals of Surgical Treatment and Research 2020;99(4):205-212
Purpose:
The aim of this study was to analyze the effects of reduced fasting time on postoperative recovery in patients who underwent totally laparoscopic distal gastrectomy (TLDG).
Methods:
This retrospective study included 347 patients who underwent TLDG. Patients were divided into 2 groups:reduced fasting time group (n = 139) and conventional feeding group (n = 208). We compared the total hospital cost and recovery parameters, such as postoperative complications, mean hospital stay, day of first flatus, initiation of soft diet, and serum CRP levels, between the 2 groups.
Results:
The reduced fasting time group had a lower total hospital cost (P < 0.001) than the conventional feeding group.Regarding postoperative complications, there was no significant difference between the 2 groups (P = 0.085). Patients in the reduced fasting time group had a significantly shorter duration of mean hospital stay (P < 0.001), an earlier first flatus (P = 0.002), an earlier initiation of soft diet (P < 0.001), and lower level of serum CRP concentration (day of surgery, P = 0.036;postoperative days 2, 5, and 7, P = 0.01, 0.009, and 0.012, respectively) than patients in the conventional feeding group.
Conclusion
Reduced fasting time can enhance postoperative recovery in patients who undergo TLDG and may reduce medical costs.
6.A Clinical Analysis of Abdominal Stab Wounds.
Jiyeon PARK ; Min CHUNG ; Yeongdon LEE ; Jungnam LEE ; Woonki LEE ; Yeonho PARK ; Jungheum BAEK ; Heunggyu PARK ; Keonkuk KIM ; Jinmo KANG ; Sangtae CHOI ; Wonsuk LEE ; Seungyoun PARK
Journal of the Korean Society of Traumatology 2010;23(2):134-141
PURPOSE: A classic approach to abdominal stab wounds has been a routine laparotomy for the purpose of diagnosis or treatment. However, management protocols for abdominal stab wounds are still contentious in most trauma centers. We examined the relationship between the character of the stab wound and the injured intraabdominal organs by retrospectively analyzing the medical records of patients with abdominal stab wounds admitted to Gil hospital, and the findings for our patients are then confronted with a review of the literature. We aimed to propose proper management protocols to approach abdominal stab wounds. METHODS: The medical records of all 80 patients sustaining abdominal stab wounds, admitted at the Department of Surgery, Gil Hospital, Gachon Medical School, from January 2004 to December 2008 were retrospectively reviewed. All the abdominal stab wounds were collated based on the site and the character of the injury, investigations performed on admission, results of investigations, operations performed and findings at the time of the operation. RESULTS: The most prevalent age group was patients in their forties and the average age of the patients was 41 years for both genders. The stab wounds were most commonly located at the periumbilical area (16.9%), followed by the epigastric area (15.6%), and 18.2% of the patients had multiple wounds. The most commonly eviscerated organ was the omentum (9 out of 16 cases); 61.7% of non-eviscerated patients underwent a therapeutic laparotomy while 81.3% of eviscerated patients underwent a therapeutic laparotomy. The small bowel was the most commonly injured organ (22.7%, 17 out of 75 injuries). The review revealed a relatively common diaphragmatic injury in abdominal stab wound patients (8 cases, 10.5%). The average hospital stay was 11 days. CONCLUSION: This review revealed commonly eviscerated and injured intraabdominal organs in abdominal stab wound patients and their relationship with a therapeutic laparotomy. Although the management is still controversial, the authors suggest indications for an immediate laparotomy and a protocol for managing abdominal stab wounds. Hemodynamic instability and peritoneal irritation signs are definite indicators for an immediate laparotomy, but the review revealed intraabdominal organ evisceration alone not to be a statistically significant factor. In addition, the authors suggest that abnormal CT findings can be valuable for making a decision on management of hemodynamically stable stab wound patients. Further study may clarify a role for a more selective approach to operative intervention and for a more extensive use of selective observation.
Hemodynamics
;
Humans
;
Laparotomy
;
Length of Stay
;
Medical Records
;
Multiple Trauma
;
Omentum
;
Retrospective Studies
;
Schools, Medical
;
Trauma Centers
;
Wounds, Stab
7.Simple Maturation of Direct-Converted Hepatocytes Derived from Fibroblasts.
Young duck CHO ; Sangtae YOON ; Kyojin KANG ; Yohan KIM ; Seung Bum LEE ; Daekwan SEO ; Kiyoung RYU ; Jaemin JEONG ; Dongho CHOI
Tissue Engineering and Regenerative Medicine 2017;14(5):579-586
Target cells differentiation techniques from stem cells are developed rapidly. Recently, direct conversion techniques are introduced in various categories. Unlike pluripotent stem cells, this technique enables direct differentiation into the other cell types such as neurons, cardiomyocytes, insulin-producing cells, and hepatocytes without going through the pluripotent stage. However, the function of these converted cells reserve an immature phenotype. Therefore, we modified the culture conditions of mouse direct converted hepatocytes (miHeps) to mature fetal characteristics, such as higher AFP and lower albumin (ALB) expression than primary hepatocytes. First, we generate miHeps from mouse embryonic fibroblasts (MEFs) with two transcription factors HNF4α and Foxa3. These cells indicate typical epithelial morphology and express hepatic proteins. To mature hepatic function, DMSO is treated during culture time for more than 7 days. After maturation, miHeps showed features of maturation such as exhibiting typical hepatocyte-like morphology, increased up-regulated ALB and CYP enzyme gene expression, down-regulated AFP expressions, and acquired hepatic function over time. Thus, our data provides a simple method to mature direct converted hepatocytes functionally and these cells enable them to move closer to generating functional hepatocytes.
Animals
;
Dimethyl Sulfoxide
;
Fibroblasts*
;
Gene Expression
;
Hepatocytes*
;
Methods
;
Mice
;
Myocytes, Cardiac
;
Neurons
;
Phenotype
;
Pluripotent Stem Cells
;
Stem Cells
;
Transcription Factors
8.Poorly differentiated thyroid carcinoma: An institutional experience
Seok Won CHOI ; Joon-Hyop LEE ; Yun Young KIM ; Yoo Seung CHUNG ; Sangtae CHOI ; Na Rae KIM ; Jin Mo KANG ; Heung Kyu PARK ; Yong Soon CHUN
Korean Journal of Clinical Oncology 2020;16(1):25-32
Purpose:
The incidence of poorly differentiated thyroid carcinoma (PDTC) is extremely low among thyroid cancers and there is no standardized treatment guideline for it. In this study, we have analyzed PDTC patients and reviewed their clinicopathological features.
Methods:
Data of PDTC patients from our institution are collected through the electronic medical database. We analyzed them by several parameters such as basic demographics, presenting symptom, preoperative cytology results, associated pathology, surgical results, surgery type, and distant metastasis.
Results:
We collected 23 cases in our institution. Apart from two patients who were transferred to another hospital upon diagnosis, all 21 operated cases are analyzed. The parameters we studied were age, sex, presenting symptoms, distant metastasis and pathological features such as tumor size, associated pathology, predominant pattern and so on. We also provided descriptive analyses according to the type of presentation and treatment; patients with distant metastasis, juvenile cancer, and concurrent hyperthyroidism. Furthermore, we provided different cases in which the initial surgical plans differed.
Conclusion
We present 21 cases of PDTC patients and clarify their clinicopathological features. Despite some limitations, this study may shed light for future research regarding treatment of PDTC patients.
9.Clinicopathological markers associated with recurrence in ductal carcinoma in situ of breast by age group
Yoonsun CHOI ; Tae Sik HWANG ; Ah Rem JEONG ; Joung Won NA ; Yun Young KIM ; Joon Hyop LEE ; Yoo Seung JUNG ; Sangtae CHOI ; Jin Mo KANG ; Heung Kyu PARK ; Yong Soon CHUN
Korean Journal of Clinical Oncology 2018;14(1):15-20
PURPOSE: In the present study, factors related to the recurrence of breast ductal carcinoma in situ (DCIS) in Korean patients were identified, and the prognostic factors for each age group were explored.METHODS: The subjects were 226 patients who were diagnosed with DCIS by histopathologic examination, and the effect of representative prognostic factors that are known already, including estrogen receptor (ER), progesterone receptor (PR) and the human epidermal growth factor receptor 2 (HER2) status, Ki-67 levels, and adjuvant therapy on the recurrence of DCIS was analyzed by using the Cox proportional hazard model.RESULTS: Among the 226 subjects, 11 patients underwent the recurrence of breast cancer. The average follow-up period was 52.7±23.5 months. The average age of the subjects was 50.6±9.3 years. Among the DCIS patients, the recurrence of breast cancer was significantly higher in the ER negative patients and those who have a Ki-67 level over 20%. However, the PR and HER2 status did not significantly affect breast cancer recurrence. The result also showed that only ER negative was a significant factor before the age of 50 years and that only the Ki-67 level over 20% was a significant factor to the patients 50 years of age or older.CONCLUSION: DCIS patients should be appropriately treated and managed depending on their age and clinicopathological factors to prevent the recurrence of DCIS.
Breast Neoplasms
;
Breast
;
Carcinoma, Ductal
;
Carcinoma, Intraductal, Noninfiltrating
;
Estrogens
;
Follow-Up Studies
;
Humans
;
Proportional Hazards Models
;
Receptor, Epidermal Growth Factor
;
Receptors, Progesterone
;
Recurrence
10.Stem cell analysis with intraductally treated mammary epithelial cells
Ah Young YOON ; Yun Young KIM ; Joon Hyop LEE ; Yoo Seung CHUNG ; Sangtae CHOI ; Jin Mo KANG ; Heung Kyu PARK ; Yong Soon CHUN
Korean Journal of Clinical Oncology 2019;15(1):27-33
PURPOSE: The activity of mammary stem cells (MaSCs) is essential to mammary growth, differentiation and regeneration in cycles of pregnancy, lactation, and involution. The capability to recruit the mammary gland through the cycles is attributed to stem cells. It was shown that the intraductal (i.duc) injection of pegylated liposomal doxorubicin (PLD) to multiparous FVB/N mice was associated with a significantly reduced outgrowth potential of mammary gland cells. We have explored i.duc PLD's effect on stem cell number and function in mouse mammary gland and aldehyde dehydrogenase (ALDH)'s availability as a mouse MaSC marker.METHODS: The total mammary epithelium was purified from 6 to 8-month-old FVB/N control and i.duc PLD-administered mice treated twice and analyzed by flow cytometry and limiting dilution cleared mammary fat pad transplants.RESULTS: There was no significant difference in the proportions of stem cell-enriched population (CD49(fhigh)CD24(med)) between control and i.duc PLD-treated groups. However, we found a significant reduction in the outgrowth potential of CD49(fhigh)CD24(med) and CD49(fhigh)CD24(med)ALDH(+) cells from i.duc PLD-treated mammary glands. We discovered that adding ALDH to CD49(fhigh)CD24(med) had the possibility of better marker selection for MaSC of mice.CONCLUSION: We present i.duc administration of PLD to reduce MaSC function, but not the number; and ALDH activity may add further selection of MaSCs to CD49f CD24 in mouse mammary glands. Screening of chemotherapeutic drugs or other natural products by this method of stem cell analysis may provide safe i.duc treatment in breast cancer.
Adipose Tissue
;
Aldehyde Dehydrogenase
;
Animals
;
Biological Products
;
Breast Neoplasms
;
Doxorubicin
;
Epithelial Cells
;
Epithelium
;
Female
;
Flow Cytometry
;
Humans
;
Infant
;
Lactation
;
Mammary Glands, Human
;
Mass Screening
;
Methods
;
Mice
;
Pregnancy
;
Regeneration
;
Stem Cells