1.Perivascular Delivery of Rapamycin in Pluronic Gel Inhibits Neointimal Hyperplasia in a Rat Carotid Artery Injury Model, and the Complementary Role of Carotid Arteriography.
Mi Jin JUNG ; Jin Sook KWON ; No Kwan PARK ; Yu Kyung KIM ; Tae Jin SHIM ; Il Ha JEONG ; Jang Whan BAE ; Kyung Kuk HWANG ; Dong Woon KIM ; Myeong Chan CHO
Korean Circulation Journal 2008;38(2):80-86
BACKGROUND AND OBJECTIVES: Rapamycin has been shown to inhibit the vascular smooth muscle cell migration and proliferation that contributes to neointimal formation. We investigated whether the perivascular delivery of rapamycin in Pluronic gel could inhibit neointimal hyperplasia in a rat carotid artery model, and we tested the usefulness of carotid arteriography. MATERIALS AND METHODS: To assess the kinetics of rapamycin's release from Pluronic gel, a [3H] thymidine incorporation assay was performed with using the media exposed to rapamycin in Pluronic gel for 10, 20, 60 and 120 min. We applied 100 microgram of rapamycin in Pluronic gel to the perivascular space of the carotid artery after the balloon injury (n=9), whereas only gel was applied in a control group (n=9). We performed the carotid arteriography and the morphometric analysis 14 days after injury. RESULTS: The [3H] thymidine incorporation assay showed a reduction of uptake in a time-dependent manner (86%, 48%, 45% and 40% of the control, respectively, at 10, 20, 60 and 120 minutes). The inhibiting effect of rapamycin on neointimal hyperplasia was identified on the carotid arteriography (mean luminal diameter; 0.75+/-0.11 vs. 0.60+/-0.12 arbitrary units, respectively, p< 0.05) and on the morphometric analysis (neointima area: 0.09+/-0.03 vs. 0.17+/-0.06 mm(2), respectively, p< 0.05). CONCLUSION: This study demonstrated that perivascular delivery of rapamycin in Pluronic gel inhibits neointimal hyperplasia in a rat carotid injury model. This animal model combined with arteriography can be used for developing new drugs to treat restenosis. In addition, this technique might be useful for vascular surgery such as coronary artery bypass grafting, arteriovenous fistula formation and peripheral vascular bypass graft insertion.
Angiography
;
Animals
;
Arteriovenous Fistula
;
Carotid Arteries
;
Carotid Artery Injuries
;
Cell Movement
;
Coronary Artery Bypass
;
Drug Delivery Systems
;
Hyperplasia
;
Kinetics
;
Models, Animal
;
Muscle, Smooth, Vascular
;
Phenobarbital
;
Rats
;
Sirolimus
;
Thymidine
;
Transplants
2.Association between Case Volume of Cardiopulmonary Resuscitation and Implementation of Therapeutic Hypothermia.
Chan Jong PARK ; Sang Do SHIN ; Chang Bae PARK ; Kyoung Jun SONG ; Yu Jin KIM ; Young Ho KWAK ; Eui Jung LEE
Journal of the Korean Society of Emergency Medicine 2011;22(5):423-430
PURPOSE: Therapeutic hypothermia (TH) is recommended as a strategic post-resuscitation care for favorable neurologic outcomes. However, information concerning the implementation of TH and associated number of cardiopulmonary resuscitation (CPR) volumes is lacking. METHODS: We conducted a telephone survey using a designed questionnaire from March to December, 2009. Information of target hospitals was collected from a national registry of out of hospital cardiac arrest (2006-2007). Hospital name, service levels of emergency department (ED; level 1-4), case volume of cardiopulmonary resuscitation given at each ED (high versus low volume by 34 cases per year derived from a previous sensitivity analysis study), population (metropolis exceeding one million residents), and year when TH was adopted were recorded. Demographics and factors associated with adaptation of TH were analyzed and odds ratios were calculated using a multivariate logistic regression model. RESULTS: A total of 39,833 OHCA cases for 2 years were transported to 840 hospitals. Of these hospitals, 461 (55.8%) were included for final analysis. Thirty four of the hospitals (7.4%) had adopted TH. Of these, 16 hospitals housed a high-volume ED (odds ratio=2.93). Twenty four hospitals were located in a metropolis (odds ratio=3.05) and 25 hospitals were ED level 1 or 2. CONCLUSION: Only 7.4% of surveyed Korean hospitals had adopted TH in Korea by the end of 2009. Hospitals with high-volume EDs adopted TH early, when adjusting for population and ED level.
Cardiopulmonary Resuscitation
;
Demography
;
Emergencies
;
Heart Arrest
;
Hypothermia
;
Korea
;
Logistic Models
;
Odds Ratio
;
Out-of-Hospital Cardiac Arrest
;
Surveys and Questionnaires
;
Telephone
3.Measurement and Estimation of Renal Size by Computed Tomography in Korean Children.
Chan Won PARK ; Nali YU ; Sin Weon YUN ; Soo Ahn CHAE ; Na Mi LEE ; Dae Yong YI ; Young Bae CHOI ; In Seok LIM
Journal of Korean Medical Science 2017;32(3):448-456
Adequate organ growth is an important aspect of growth evaluation in children. Renal size is an important indicator of adequate renal growth; computed tomography (CT) can closely estimate actual kidney size. However, insufficient data are available on normal renal size as measured by CT. This study aimed to evaluate the relationships of anthropometric indices with renal length and volume measured by CT in Korean pediatric patients. Renal length and volume were measured using CT images in 272 pediatric patients (age < 18 years) without renal disease. Data for anthropometric indices—including height, weight, and body surface area (BSA)—were obtained using medical records. Using the equation for an ellipsoid, renal volume was calculated in cubic centimeters. Height showed greatest correlation with renal length on stepwise multiple linear regression analysis; BSA showed the strongest significant correlation with renal volume. The mean renal size for each age group and height group was determined; it showed a tendency to increase with age and height. This is the first Korean study to report the relationship between body indices and renal size measured by CT. These results can serve as normative standards for assessing adequate renal growth.
Body Surface Area
;
Child*
;
Humans
;
Kidney
;
Linear Models
;
Medical Records
;
Regression Analysis
4.A Slight Variation in the Age of Rats Commonly used as a Carotid Artery Injury Model Results in a Large Difference in Neointima Formation.
Jin Sook KWON ; No Kwan PARK ; Il Ha JEONG ; Yu Kyung KIM ; Jang Han BAE ; Kyung Kuk HWANG ; Dong Woon KIM ; Myeong Chan CHO
Korean Circulation Journal 2007;37(2):78-83
BACKGROUND AND OBJECTIVES: The degree of neointima formation after infliction of a carotid artery balloon injury in rats varies greatly depending on the sex, age, species and operational method. Strong variation is common, even within only a single control. This study attempted to find if there was any significant difference in neointima formation following a carotid artery balloon injury in 6 to 12 week old rats; the age commonly used in these types of experiments. MATERIALS AND METHODS: A balloon injury was inflicted on the carotid arteries of male SpragueDawley rats at 6 (n=9, 250-270 g), 8 (n=8, 280-300 g) and 11 weeks (n=10, 320-340 g) of age. Two weeks postoperation, a histomorphometric analysis was carried out. The vascular smooth muscle cell proliferation was measured in situ via BrdU incorporation 2 days after injury infliction. RESULTS: The neointima areas of the 6 week (0.22+/-0.04 mm2) and 8 week old groups (0.17+/-0.08 mm2) were 3.1 and 2.4 times larger than that of the 11 week old group (0.07+/-0.03 mm2). The mitotic index was significantly reduced in 11 week old group (n=4, 9.22+/-1.51%) compared to those of the 6 (n=4, 25.03+/-3.92%) and 8 week old (n=4, 21.66+/-3.66%) groups. CONCLUSION: Special care should be taken when interpreting neointima formation, as even a slight variation in the age and weight in 6 to 12 week old (250-340 g) rats; the age commonly used in these types of experiments, results in an unexpectedly large difference.
Aging
;
Animals
;
Bromodeoxyuridine
;
Carotid Arteries*
;
Carotid Artery Injuries*
;
Cell Proliferation
;
Humans
;
Male
;
Mitotic Index
;
Muscle, Smooth, Vascular
;
Neointima*
;
Rats*
5.A novel method for the management of proximal segment using computer assisted simulation surgery: correct condyle head positioning and better proximal segment placement.
Yong Chan LEE ; Hong Bum SOHN ; Sung Keun KIM ; On Yu BAE ; Jang Ha LEE
Maxillofacial Plastic and Reconstructive Surgery 2015;37(7):21-
Computer Assisted Simulation Surgery (CASS) is a reliable method that permits oral and maxillofacial surgeons to visualize the position of the maxilla and the mandible as observed in the patient. The purpose of this report was to introduce a newly developed strategy for proximal segment management according to Balanced Orthognathic Surgery (BOS) protocol which is a type of CASS, and to establish the clinical feasibility of the BOS protocol in the treatment of complex maxillo-facial deformities. The BOS protocol consists of the following 4 phases: 1) Planning and simulation phase, 2) Modeling phase, 3) Surgical phase, and 4) Evaluation phase. The surgical interventions in 80 consecutive patients were planned and executed by the BOS protocol. The BOS protocol ensures accuracy during surgery, thereby facilitating the completion of procedures without any complications. The BOS protocol may be a complete solution that enables an orthognatic surgeon to perform accurate surgery based on a surgical plan, making real outcomes as close to pre-planned outcomes as possible.
Congenital Abnormalities
;
Head*
;
Humans
;
Mandible
;
Maxilla
;
Methods*
;
Oral and Maxillofacial Surgeons
;
Orthognathic Surgery
6.Biocompatibility of experimental mixture of mineral trioxide aggregate and glass ionomer cement.
Min Jae OH ; Yu Na JEONG ; In Ho BAE ; So Young YANG ; Bum Jun PARK ; Jeong Tae KOH ; Yun Chan HWANG ; In Nam HWANG ; Won Mann OH
Journal of Korean Academy of Conservative Dentistry 2010;35(5):359-367
OBJECTIVES: The purpose of the present in vitro study was to evaluate the biocompatibility of mineral trioxide aggregate (MTA) mixed with glass ionomer cement (GIC), and to compare it with that of MTA, GIC, IRM and SuperEBA. MATERIALS AND METHODS: Experimental groups were divided into 3 groups such as 1 : 1, 2 : 1, and 1 : 2 groups depending on the mixing ratios of MTA powder and GIC powder. Instead of distilled water, GIC liquid was mixed with the powder. This study was carried out using MG-63 cells derived from human osteosarcoma. They were incubated for 1 day on the surfaces of disc samples and examined by scanning electron microscopy. To evaluate the cytotoxicity of test materials quantitatively, XTT assay was used. The cells were exposed to the extracts and incubated. Cell viability was recorded by measuring the optical density of each test well in reference to controls. RESULTS: The SEM revealed that elongated, dense, and almost confluent cells were observed in the cultures of MTA mixed with GIC, MTA and GIC. On the contrary, cells on the surface of IRM or SuperEBA were round in shape. In XTT assay, cell viability of MTA mixed with GIC group was similar to that of MTA or GIC at all time points. IRM and SuperEBA showed significantly lower cell viability than other groups at all time points (p < 0.05). CONCLUSIONS: In this research MTA mixed with GIC showed similar cellular responses as MTA and GIC. It suggests that MTA mixed with GIC has good biocompatibility like MTA and GIC.
Acrylic Resins
;
Aluminum Compounds
;
Calcium Compounds
;
Cell Survival
;
Drug Combinations
;
Glass
;
Glass Ionomer Cements
;
Glutamates
;
Guanine
;
Humans
;
Microscopy, Electron, Scanning
;
Osteosarcoma
;
Oxides
;
Silicates
;
Silicon Dioxide
;
Water
;
Pemetrexed
7.A Study on the Development of M.D.-Ph.D. Program.
Moo Sang LEE ; Eun Bae YANG ; Sun KIM ; Chan Il PARK ; Se Jong KIM ; Kyung Hwan KIM ; Kwang Se PAIK ; Seung Hum YU
Korean Journal of Medical Education 2000;12(2):309-327
This study is to develop M.D.-Ph.D. program of medical school in Korea. The authors examined the related literature focusing on the current status and problems of training biomedical scientists. Next step was to make a collection of data related to American M.D.-Ph.D. program. The search for the materials was made through February 2000. The developed M.D.-Ph.D. program was modified and revised by the experts in the area and through public speech. The results of the study are as follows; first, the validity of M.D.-Ph.D. program was convicted by the need of interdisciplinary study, social needs, current problems of medical education and financial problems. Second, the development M.D.-Ph.D. program consists of educational period, admission procedure, entree examination, curriculum and its administration, degrees, school registration management, medical license examination, grants and problems related to military service. The expectations of the results are; first, M.D.-Ph.D. program will make Korea one of the leading countries in biomedical scientists and medical knowledge, and will activate the interdisciplinary research. Second, M.D.-Ph.D. program will facilitate to revise the educational problems of graduate school of medicine and medical schools.
Curriculum
;
Education, Medical
;
Financing, Organized
;
Humans
;
Interdisciplinary Studies
;
Korea
;
Licensure
;
Military Personnel
;
Schools, Medical
8.Pathogenicity of clade 2.3.4.4 H5N6 highly pathogenic avian influenza virus in three chicken breeds from South Korea in 2016/2017
Seok Chan PARK ; Byung Min SONG ; Yu Na LEE ; Eun Kyoung LEE ; Gyeong Beom HEO ; Soo Jeong KYE ; Kyung hyun LEE ; You Chan BAE ; Youn Jeong LEE ; Bumseok KIM
Journal of Veterinary Science 2019;20(3):e27-
In 2016, novel H5N6 highly pathogenic avian influenza virus emerged in Korea. During the outbreak, the virus caused the largest culling, especially in brown chicken lines. We determined the pathogenicity and transmissibility of the virus in 2 white chicken lines of the specific pathogen-free chickens, broilers and brown chicken line of Korean native chicken (KNC). A KNC had a longer virus shedding period and longer mean death time than others. Our study showed that this characteristic in the KNC might have contributed to a farm-to-farm transmission of the brown chicken farms.
Agriculture
;
Animals
;
Chickens
;
Influenza in Birds
;
Korea
;
Virulence
;
Virus Shedding
9.Insulin Secretion and Insulin Resistance Trajectories over 1 Year after Kidney Transplantation: A Multicenter Prospective Cohort Study
Jun Bae BANG ; Chang-Kwon OH ; Yu Seun KIM ; Sung Hoon KIM ; Hee Chul YU ; Chan-Duck KIM ; Man Ki JU ; Byung Jun SO ; Sang Ho LEE ; Sang Youb HAN ; Cheol Woong JUNG ; Joong Kyung KIM ; Su Hyung LEE ; Ja Young JEON
Endocrinology and Metabolism 2020;35(4):820-829
Background:
We investigated the changing patterns of insulin secretion and resistance and risk factors contributing to the development of post-transplant diabetes mellitus (PTDM) in kidney recipients under tacrolimus-based immunosuppression regimen during 1 year after transplantation.
Methods:
This was a multicenter prospective cohort study. Of the 168 subjects enrolled in this study, we analyzed a total 87 kidney transplant recipients without diabetes which was assessed by oral glucose tolerance test before transplantation. We evaluated the incidence of PTDM and followed up the index of insulin secretion (insulinogenic index [IGI]) and resistance (homeostatic model assessment for insulin resistance [HOMA-IR]) at 3, 6, 9 months, and 1 year after transplantation by oral glucose tolerance test and diabetes treatment. We also assessed the risk factors for incident PTDM.
Results:
PTDM developed in 23 of 87 subjects (26.4%) during 1 year after transplantation. More than half of total PTDM (56.5%) occurred in the first 3 months after transplantation. During 1 year after transplantation, insulin resistance (HOMA-IR) was increased in both PTDM and no PTDM group. In no PTDM group, the increase in insulin secretory function to overcome insulin resistance was also observed. However, PTDM group showed no increase in insulin secretion function (IGI). Old age, status of prediabetes and episode of acute rejection were significantly associated with the development of PTDM.
Conclusion
In tacrolimus-based immunosuppressive drugs regimen, impaired insulin secretory function for reduced insulin sensitivity contributed to the development of PTDM than insulin resistance during 1 year after transplantation.
10.A Multicenter Retrospective Analysis of the Clinical Features of Pernicious Anemia in a Korean Population.
Ik Chan SONG ; Hyo Jin LEE ; Han Jo KIM ; Sang Byung BAE ; Kyu Taek LEE ; Young Jun YANG ; Suk Young PARK ; Do Yeun CHO ; Nae Yu KIM ; In Sung CHO ; Deog Yeon JO
Journal of Korean Medical Science 2013;28(2):200-204
To determine the approximate incidence and clinical features of pernicious anemia in a Korean population, we retrospectively analyzed clinical data for patients with pernicious anemia who were diagnosed between 1995 and 2010 at five hospitals in Chungnam province. Ninety-seven patients were enrolled, who accounted for 24% of patients with vitamin B12 deficiency anemia. The approximate annual incidence of pernicious anemia was 0.3 per 100,000. The median age was 66 (range, 32-98) yr, and the male/female ratio was 1.25. Anemia-associated discomfort was the most common symptom (79.4%), followed by gastrointestinal and neurological symptoms (78.4% and 38.1%, respectively). Pancytopenia was found in 36 patients (37.1%), and autoimmune disorders were found in 15 patients (15.5%). Antibody to intrinsic factor was detected in 62 (77.5%) of 80 patients examined, and antibody to parietal cells was detected in 35 (43.2%) of 81 patients examined. Of the 34 patients who underwent tests for Helicobacter pylori, 7 (12.5%) were positive. The anemia-associated and gastrointestinal symptoms resolved completely in all patients after intramuscular injection of cobalamin, whereas neurological symptoms remained in some. In conclusion, pernicious anemia is less frequent in Koreans than in Western populations; however, the clinical features of this disorder in Koreans do not differ from those of Western cases.
Adult
;
Aged
;
Anemia, Pernicious/complications/*diagnosis/epidemiology
;
Asian Continental Ancestry Group
;
Autoimmune Diseases/complications/epidemiology
;
Female
;
Gastrointestinal Diseases/complications/drug therapy/epidemiology
;
Helicobacter Infections/diagnosis
;
Helicobacter pylori
;
Humans
;
Isoantibodies/blood
;
Male
;
Middle Aged
;
Nervous System Diseases/complications/epidemiology
;
Parietal Cells, Gastric/immunology
;
Republic of Korea/epidemiology
;
Retrospective Studies
;
Vitamin B 12/blood/therapeutic use