Radon, the primary constituent of natural radiation, is the second leading environmental cause of lung cancer after smoking. To confirm a relationship between indoor radon exposure and lung cancer, estimating cumulative levels of exposure to indoor radon for an individual or population is necessary. This study sought to develop a model for estimate indoor radon concentrations in Korea. Especially, our model and method may have wider application to other residences, not to specific site, and can be used in situations where actual measurements for input variables are lacking. In order to develop a model, indoor radon concentrations were measured at 196 ground floor residences using passive alpha-track detectors between January and April 2016. The arithmetic mean (AM) and geometric mean (GM) means of indoor radon concentrations were 117.86±72.03 and 95.13±2.02 Bq/m³, respectively. Questionnaires were administered to assess the characteristics of each residence, the environment around the measuring equipment, and lifestyles of the residents. Also, national data on indoor radon concentrations at 7643 detached houses for 2011-2014 were reviewed to determine radon concentrations in the soil, and meteorological data on temperature and wind speed were utilized to approximate ventilation rates. The estimated ventilation rates and radon exhalation rates from the soil varied from 0.18 to 0.98/hr (AM, 0.59±0.17/hr) and 326.33 to 1392.77 Bq/m²/hr (AM, 777.45±257.39; GM, 735.67±1.40 Bq/m²/hr), respectively. With these results, the developed model was applied to estimate indoor radon concentrations for 157 residences (80% of all 196 residences), which were randomly sampled. The results were in better agreement for Gyeonggi and Seoul than for other regions of Korea. Overall, the actual and estimated radon concentrations were in better agreement, except for a few low-concentration residences.
Background Radiation ; Exhalation ; Gyeonggi-do ; Korea ; Life Style ; Lung Neoplasms ; Methods ; Models, Theoretical ; Radon ; Seoul ; Smoke ; Smoking ; Soil ; Ventilation ; Wind

Radon, the primary constituent of natural radiation, is the second leading environmental cause of lung cancer after smoking. To confirm a relationship between indoor radon exposure and lung cancer, estimating cumulative levels of exposure to indoor radon for an individual or population is necessary. This study sought to develop a model for estimate indoor radon concentrations in Korea. Especially, our model and method may have wider application to other residences, not to specific site, and can be used in situations where actual measurements for input variables are lacking. In order to develop a model, indoor radon concentrations were measured at 196 ground floor residences using passive alpha-track detectors between January and April 2016. The arithmetic mean (AM) and geometric mean (GM) means of indoor radon concentrations were 117.86±72.03 and 95.13±2.02 Bq/m³, respectively. Questionnaires were administered to assess the characteristics of each residence, the environment around the measuring equipment, and lifestyles of the residents. Also, national data on indoor radon concentrations at 7643 detached houses for 2011-2014 were reviewed to determine radon concentrations in the soil, and meteorological data on temperature and wind speed were utilized to approximate ventilation rates. The estimated ventilation rates and radon exhalation rates from the soil varied from 0.18 to 0.98/hr (AM, 0.59±0.17/hr) and 326.33 to 1392.77 Bq/m²/hr (AM, 777.45±257.39; GM, 735.67±1.40 Bq/m²/hr), respectively. With these results, the developed model was applied to estimate indoor radon concentrations for 157 residences (80% of all 196 residences), which were randomly sampled. The results were in better agreement for Gyeonggi and Seoul than for other regions of Korea. Overall, the actual and estimated radon concentrations were in better agreement, except for a few low-concentration residences.
Background Radiation ; Exhalation ; Gyeonggi-do ; Korea ; Life Style ; Lung Neoplasms ; Methods ; Models, Theoretical ; Radon* ; Seoul ; Smoke ; Smoking ; Soil ; Ventilation ; Wind

BACKGROUND: Malignant fibrous/fibrohistiocytic tumors are uncommon soft tissue tumors which gives dermatologists special attention on differential diagnosis. However, there has not yet been a multicenter study on these tumors in Korea. OBJECTIVE: The aim of this study was to investigate the epidemiology and clinical features of malignant fibrous/ fiborhistiocytic tumors. METHODS: A total of 62 patients from 11 training hospitals who had been confirmed with malignant fibrous/ fibrohistiocytic tumor were studied. A retrospective analysis of hospital records served as the data source for this study. RESULTS: Among patients with malignant fibrous/fibrohistiocytic tumors, the most common tumor type was dermatofibrosarcoma protuberance followed by malignant fibrohistiocytic. The male to female ratio among subjects was 1.38 to 1 and the mean age was 44 years old. Of the common complaints recorded, asymptomatic mass was the most frequent. The mean size of the subjects' tumors was 2.9 cm in the long axis and 2.3 cm in the short axis with a mean tumor thickness of 2.1 mm. The most common site for tumors was the back followed by the thigh. The recurrence rate after primary treatment was 14.5% and metastasis developed in 5 of 62 patients. CONCLUSION: This study is expected to be helpful for understanding the clinical and pathological characteristics of malignant fibrous/fibrohistiocytic tumors.
Axis, Cervical Vertebra ; Information Storage and Retrieval ; Dermatofibrosarcoma ; Diagnosis, Differential ; Female ; Hospital Records ; Humans ; Korea ; Male ; Neoplasm Metastasis ; Recurrence ; Retrospective Studies ; Thigh

PURPOSE: Tc-99m labeled diethylenetriaminepentaacetic acid (DTPA) -coupled galactosylated human serum albumin (GSA) is a currently used imaging agent for asialoglycoprotein receptor (ASGPR) of the liver, but, it has several shortcomings. Recently a new ASGPR imaging agent, (99m) Tc-lactosylated human serum albumin (LSA), with simple labeling procedure, high labeling efficiency, high stability was developed. In order to assess the feasibility of the (99m) Tc-LSA as a ASGPR imaging radiopharmaceuticals, we performed biodistribution study of the tracer in liver injured mice model and the results were compared with histolgic data. MATERIALS AND METHODS: To induce hepatic damage in ICR mice, diethylnitrosamine (DEN) (60 mg/kg/week X 5 time, low dose or 180 mg/kg/week X 2 times, high dose) and thioacetamide (TAA) (50 mg/kg X 1 time) were administrated intraperitoneally. Degree of liver damage was evaluated by tissue hematoxilin-eosin stain, and expression of asialoglycoprotein receptor (ASGPR) was assessed by immunohistochemistry using ASGPR antibody. (99m) Tc-LSA was intravenously administrated via tail vein in DEN or TAA treated mice, and biodistribution study of the tracer was also performed. RESULTS: DEN treated mice showed ballooning of hepatocyte and inflammatory cell infiltration in low dose group and severe hapatocyte necrosis in high dose group, and low dose group showed higher ASGPR staining than control mice in immunohistochemical staining. TAA treated mice showed severe hepatic necrosis. (99m) Tc-LSA Biodistribution study showed that mice with hepatic necrosis induced by high dose DEN or TAA revealed higher blood activity and lower liver activity than control mice, due to slow clearance of the tracer by the liver. The degree of liver uptake was inversely correlated with the degree of histologic liver damage. But low dose DEN treated mice with mild hepatic injury showed normal blood clearance and hepatic activity, partly due to overexpression of ASGPR in mice with mild degree hepatic injury. CONCLUSION: Liver uptake of (99m) Tc-LSA was inversely correlated with degree of histologic hepatic injury in DEN and TAA treated mice. These results support that (99m) Tc-LSA can be used to evaluate the liver status in liver disease patients.
Animals ; Asialoglycoprotein Receptor ; Diethylnitrosamine* ; Hepatocytes ; Humans ; Immunohistochemistry ; Liver Diseases ; Liver* ; Mice* ; Mice, Inbred ICR ; Necrosis ; Radiopharmaceuticals ; Serum Albumin* ; Thioacetamide* ; Veins

Left ventricular thrombosis is a frequent and potentially dangerous complication in acute myocardiac infarction, but its occurrence and adequate therapy has not been known in patients with Dor procedure for the ischemic cardiomyopathy. We report a patient, 45 year-old male, who had a new left ventricular thrombus developed after coronary arterial bypass graft, Dor procedure, and removal of the left ventricular thrombus for ischemic cardiomyopathy. Left ventricular thrombus was disappeared on the follow-up cardiac MRI following intravenous heparin injection and oral coumadin therapy. This case suggest that anticoagulation therapy may prevent patients with the severe left ventricular dysfunction and apical aneurysm and dyskinesia from developing the left ventricular thrombus, and that thrombi will resolve without clinical evidence of systemic embolism.
Aneurysm ; Cardiomyopathies ; Dyskinesias ; Embolism ; Follow-Up Studies ; Heart Aneurysm ; Heparin ; Humans ; Infarction ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Thrombosis* ; Transplants ; Ventricular Dysfunction, Left ; Warfarin

Annuloaortic ectasia, aortic regurgitation (AR), and ventricular septal defect (VSD) in patients with right ventricular hypoplasia is a very rare condition. We report a patient who underwent aortic root replacement with a composite graft for annuloaortic ectasia associated with VSD and AR in right ventricular hypoplasia. The patient was a 19 year-old male. Transthoraic echocardiogram and cardiac catheterization revealed a perimembranous VSD (2 cm in diameter), severe AR, annuloaortic ectasia, bipartite right ventricle with hypoplasia, and hypoplastic tricuspid valve. Operative findings showed that free margins of the right and noncoronary cusps were markedly elongated, thickened, and retracted, and commissure between the right coronary cusp and the noncoronary cusp was fused and calcified. VSD was closed with an autologous pericardial patch and composite graft aortic root replacement using direct coronary button reimplantation was performed, and the hypertrophic muscle of the right ventricular outflow tract was resected. The patient had transient weaning failure of cardiopulmonary bypass and was discharged at the postoperative 14 days without any problems.
Aortic Valve Insufficiency* ; Cardiac Catheterization ; Cardiac Catheters ; Cardiopulmonary Bypass ; Dilatation, Pathologic* ; Heart Septal Defects, Ventricular* ; Heart Ventricles ; Humans ; Male ; Replantation ; Transplants ; Tricuspid Valve ; Weaning ; Young Adult

BACKGROUND: The long-term results of combined mitral valve repair and aortic valve replacement (AVR) have not been well evaluated. This study was performed to investigate the early and long-term results of mitral valve repair with AVR. MATERIAL AND METHOD: We retrospectively reviewed 45 patients who underwent mitral valve repair and AVR between September 1990 and April 2002. The average age was 47 years; 28 were men and 17 women. Twelve patients had atrial fibrillation and three had a previous cardiac operation. The mitral valve disease consisted of pure insufficiency (MR) in 34 patients, mitral stenosis (MS) in 3, and mixed lesion in 8. Mitral valve disease was due to rheumatic origin in 24 patients, degenerative in 11, annular dilatation in 8, and ischemia or endocarditis in 2. The functional anatomy of mitral valve was annular dilatation in 31 patients, chordal elongation in 19, leaflet thickening in 19, commissural fusion in 13, chordal fusion in 10, chordal rupture in 6, and so on. Aortic prostheses used included mechanical valve in 32 patients, tissue valve in 12, and pulmonary autograft in one. The techniques of mitral valve repair included annuloplasty in 32 patients and various valvuloplasty of 54 techniques in 29 patients. Total cardiopulmonary bypass and aortic cross clamp time were 204+/-62 minute and 153+/-57 minutes, respectively. RESULT: Early death was in one patient due to low output syndrome (2.2%). After follow up of 57+/-37 months, late death was in one patient and the actuarial survival at 10 years was 96+/-4%. Recurrent MR developed grade II or III in 11 patients and moderate MS in 3. Three patients required reoperation for valve-related complications. The actuarial freedom from recurrent MR, MS, and reoperation were 64+/-11%, 86+/-8%, and 89+/-7% respectively. CONCLUSION: Combined mitral valve repair with AVR offers good early and long-term survival, and adequate techniques and selection of indication of mitral valve repair, especially in rheumatic disease, are prerequisites for better long-term results.
Aortic Valve* ; Atrial Fibrillation ; Autografts ; Cardiopulmonary Bypass ; Dilatation ; Endocarditis ; Female ; Follow-Up Studies ; Freedom ; Humans ; Ischemia ; Male ; Mitral Valve Stenosis ; Mitral Valve* ; Prostheses and Implants ; Reoperation ; Retrospective Studies ; Rheumatic Diseases ; Rupture

BACKGROUND: We analysed the surgical outcomes of immediate reoperations after mitral valve repair. MATERIAL AND METHOD: Eighteen patients who underwent immediate reoperation for failed mitral valve repair from April 1995 through July 2001 were reviewed retrospectively. There were 13 female patients. The mitral valve disease was regurgitation (MR) in 12 patients, stenosis (MS) in 3, and mixed lesion in 3. The etiologies of the valve disease were rheumatic in 9 patients, degenerative in 8, and endocarditis in 1. The causes of reoperation was residual MR in 13 patients, residual MS in 4, and rupture of left ventricle in 1. Fourteen patients had rerepair for residual mitral lesions (77.8%) and four underwent replacement. RESULT: There was no early death. After mean follow-up of 33 months, there was one late death. Echocardiography revealed no or grade I of MR (64.3%) in 9 patients and no or mild MS in 11 patients (78.6%). Reoperation was done in one patient. The cumulative survival and freedom from valve-related reoperation at 6 years were 94% and 90%, respectively. The cumulative freedom from recurrent MR and MS at 4 years were 56% and 44%, respectively. CONCLUSION: This study suggests that immediate reoperation for failed mitral valve repair offers good early and intermediate survival, and mitral valve rerepair can be successfully performed in most of patients. However, because mitral rerepair have high failure rate, especially in rheumatic valve disease, adequate selections of valvuloplasty technique and indication are important to reduce the failure rate of mitral rerepair.
Constriction, Pathologic ; Echocardiography ; Endocarditis ; Female ; Follow-Up Studies ; Freedom ; Heart Ventricles ; Humans ; Mitral Valve* ; Reoperation* ; Retrospective Studies ; Rupture

Pacemaker lead-related infective endocarditis is an uncommon, but serious complication. We report a case of a 45-year-old man who had symptom of intermittent high fever and rupture of sinus Valsalva that developed after a redo aortic valve replacement and transvenous permanent pacemaker implantation. Positive blood cultures of streptococcus viridans and transesophageal echocardiography showing a large mobile vegetation on pacemaker lead and tricuspid valve lead to the diagnosis of pacemaker lead-related infective endocarditis. Initial antibiotic therapy followed by surgical extraction of the pacemaker lead and wide debridement of infective tissues including multiple vegetations was required. Postoperative antibiotic therapy was continued for 4 weeks. The postoperative course has been uneventful. The patient is totally asymptomatic and is doing well up to now.
Aortic Valve* ; Debridement ; Diagnosis ; Echocardiography, Transesophageal ; Endocarditis* ; Fever ; Humans ; Middle Aged ; Rupture* ; Tricuspid Valve ; Viridans Streptococci

Obstructive intracardiac lesions, like mitral stenosis or insufficiency (MR), by myxomas of the left atrium have been commonly reported, but the attenuation of MR by myxoma combined with coronary artery disease is very rare. We report a 70-year-old female patient whose left atrial myxoma had attenuated moderate MR to mild MR and required mitral valve surgery after removal of the myxoma. She also had coronary artery disease, severe pulmonary hypertension and moderate tricuspid regurgitation due to the mitral valve lesions obstructed by myxoma. The patient underwent removal of myxoma, mitral and tricuspid valve reconstructions, and coronary artery bypass grafting. She was discharged at the postoperative 14 day without any problems.
Aged ; Coronary Artery Bypass ; Coronary Artery Disease* ; Coronary Vessels* ; Female ; Heart Atria ; Humans ; Hypertension, Pulmonary ; Mitral Valve ; Mitral Valve Insufficiency* ; Mitral Valve Stenosis ; Myxoma* ; Tricuspid Valve ; Tricuspid Valve Insufficiency