Recently, along with technology development of endoscopic equipment, a stent has been developed for the convenience of operation, shortening of recovery times, and reduction of patient's pain. To this end, optimal factors are simulated for the stent structure and mechanical reaction and verified using finite element analysis. In order to compare to present commercialized product such as Zilver (Cook, Bloomington, Indiana, USA) and S.M.A.R.T (Cordis, Bridgewater Towsnhip, New Jersey, USA), mechanical impact factors were determined through Taguchi factor analysis, and flexibility and expandability of all the products including ours were tested using finite element analysis. Also, important factors were sought that fulfill the optimal condition using central composition method of response surface analysis, and optimal design were carried out based on the important factors. From the centra composition method of Response surface analysis, it is found that importat factors for flexibility is stent thickness (T) and unit area (W) and those for expandability is stent thickness (T). In results, important factors for optimum condition are 0.17 mm for stent thickness (T) and 0.09 mm2 for unit area (W). Determined and verified by finite element analysis in out research institute, a stent was manufactured and tested with the results of better flexibility and expandability in optimal condition compared to other products. Recently, As Finite element analysis stent mechanical property assessment for research much proceed. But time and reduce expenses research rarely stent of optimum coditions. In this research, Important factor as mechanical impact factor stent Taguchi factor analysis arrangement to find flexibility with expansibility as Finite element analysis. Also, Using to Center composition method of Response surface method appropriate optimized condition searching for important factor, these considering had design optimized. Production stent time and reduce expenses was able to do the more coincide with optimum conditions. These kind of things as application plan industry of stent development period of time and reduce expenses etc. be of help to many economic development.
Academies and Institutes ; Finite Element Analysis ; Indiana ; New Jersey ; Pliability ; Stents

PURPOSE: The aim of this study is to evaluate the value of pleural adenosine deaminase (ADA) in differentiating tuberculous pleural effusion from non tuberculous pleural effusion of children. METHODS: We measured pleural ADA activity in patients with pleural effusion whose age were from seven months to seventeen years from January 1995 to October 2001. By some criteria the patients were grouped to tuberculous pleural effusion, bacterial effusion, mycoplasma effusion, malignant effusion, and other effusion. RESULTS: The mean pleural ADA activity in tuberculous pleural effusion was 86.2+/-27.3 U/L. Pleural ADA activities in bacterial effusion, mycoplasma effusion, malignant effusion, other effusion were 32.6+/-20.1, 22.1+/-15.4, 23.1+/-10.9, 36.7+/-28.4 U/L, respectively. Pleural ADA activity in tuberculous pleural effusion was significantly higher than in any other group(P<0.001). At a level of 50 U/L, the sensitivity, specificity, positive predictive value (ppv), and and negative predictive value(npv) for the identification of tuberculous pleural effusion from nontuberculous pleural effusion were calculated at 93.8%, 84.8%, 81.1%, 95.1%, respectively. CONCLUSION: Pleural ADA is a useful test in the diagnosis of tuberculous pleural effusion of children from nontuberculous pleural effusion.
Adenosine Deaminase* ; Adenosine* ; Child* ; Diagnosis* ; Humans ; Mycoplasma ; Pleural Effusion* ; Sensitivity and Specificity

BACKGROUND: Atrial fibrillation is the commonest arrhythmia seen in clinical practice. However, there have been no epidemiologic data on its prevalence in general population of Korea. We performed this study to investigate the prevalence of atrial fibrillation in Korea. METHODS: From March 1, 1999 to July 31, 2000, Kangwon Branch, Korea Association of Health (KAH) parformed electrocardiograms to investigate the health status in the general public in Kangwon Province. We analyzed these data by of chi square(2) test. RESULTS: A total of 45,133 persons participated in the health screening performed by KAH. The number of persons above 40 years old were 13,768, with men and women 6,367 (46.2%) and 7,401 (53.8%)respectively. Prevalence among those above 40 years old was 0.72% and the prevalence among men, 0.96% (61 persons) was significantly higher than that of women, 0.51% (38 persons)(p<0.01). In the group above 60 years old with the prevalence of 1.24%, a similar phenomenon was observed with 1.57% (40 persons) in men and 0.97% (29 persons) in women (p<0.05). CONCLUSION: Prevalence of atrial fibrillation became higher as age increased, specifically in persons older than 40 years.
Adult ; Arrhythmias, Cardiac ; Atrial Fibrillation* ; Electrocardiography ; Female ; Gangwon-do* ; Humans ; Korea ; Male ; Mass Screening ; Middle Aged ; Prevalence*

BACKGROUND: The aim of this study was to evaluate causes of unstable total knee arthroplasty and results of revision surgery. METHODS: We retrospectively reviewed 24 knees that underwent a revision arthroplasty for unstable total knee arthroplasty. The average follow-up period was 33.8 months. We classified the instability and analyzed the treatment results according to its cause. Stress radiographs, postoperative component position, and joint level were measured. Clinical outcomes were assessed using the Hospital for Special Surgery (HSS) score and range of motion. RESULTS: Causes of instability included coronal instability with posteromedial polyethylene wear and lateral laxity in 13 knees, coronal instability with posteromedial polyethylene wear in 6 knees and coronal and sagittal instability in 3 knees including post breakage in 1 knee, global instability in 1 knee and flexion instability in 1 knee. Mean preoperative/postoperative varus and valgus angles were 5.8degrees/3.2degrees (p = 0.713) and 22.5degrees/5.6degrees (p = 0.032). Mean postoperative alpha, beta, gamma, delta angle were 5.34degrees, 89.65degrees, 2.74degrees, 6.77degrees. Mean changes of joint levels were from 14.1 mm to 13.6 mm from fibular head (p = 0.82). The mean HSS score improved from 53.4 to 89.2 (p = 0.04). The average range of motion was changed from 123degrees to 122degrees (p = 0.82). CONCLUSIONS: Revision total knee arthroplasty with or without a more constrained prosthesis will be a definite solution for an unstable total knee arthroplasty. The solution according to cause is very important and seems to be helpful to avoid unnecessary over-constrained implant selection in revision surgery for total knee instability.
Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee/*adverse effects ; Female ; Humans ; Joint Instability/*etiology ; Knee Joint/*surgery ; Knee Prosthesis ; Male ; Middle Aged ; *Prosthesis Failure ; Reoperation ; Retrospective Studies

STUDY DESIGN: Retrospective study. PURPOSE: To determine the prevalence of high risk patient with osteopenia requiring pharmacologic treatment and investigate the difference of 10-year fracture probability whether bone mineral density (BMD) include or not in Korean FRAX model. OVERVIEW OF LITERATURE: Many people with the fracture have osteopenia rather than osteoporosis, and BMD alone could be considered as a chance to prevent fracture. METHODS: Three hundred sixty-nine patients who was diagnosed as osteopenia were divided into two groups according to age (group 1, under 65 years; group 2, over 65 years), and 10-year fracture probabilities were calculated by FRAX algorithm with and without femur neck T-score. RESULTS: The high risk patients of the fracture who had above 3% of 10-year hip fracture probability were 15 cases in group 1 and 121 cases in group 2. In 193 patients of group 1, the mean 10-year fracture probability with BMD was significantly higher than the results without BMD (hip fracture: p=0.04, major osteoporotic fracture: p=0.01). Unlike the results of the group 1, the mean 10-year fracture probability without BMD was significantly higher than the results with BMD in 176 patients of group 2 (hip fracture: p=0.01, major osteoporotic fracture: p=0.01). CONCLUSIONS: Total of 136 cases (36.8%) as a high risk of the fracture with osteopenia could be overlooked treatment eligibility in Korean. The Korean FRAX model without BMD could be effective in predicting fracture risk especially in the individuals who were over 65 years.
Bone Density ; Bone Diseases, Metabolic* ; Femur Neck ; Hip ; Humans ; Osteoporosis ; Osteoporotic Fractures ; Prevalence ; Retrospective Studies ; Risk Assessment

BACKGROUND: Deep vein thrombosis (DVT) and pulmonary embolism (PE) are conditions with significant morbidity and mortality. Proximal DVT has a significant association with PE and possible fatal outcomes. Traditionally, PE is subdivided into symptomatic PE and asymptomatic PE, which have different treatments, preventions and prognoses. The growing utilization of computed tomography pulmonary angiography has led to increased detection of PE in DVT patients. This study examined the clinical characteristics and compared symptomatic PE and asymptomatic PE following proximal DVT. METHODS: The medical records of 258 DVT inpatients from July, 2012 to June, 2015 were reviewed retrospectively. After excluding the patients who did not performed PE evaluation and were not diagnosed with PE, 95 patients diagnosed with PE following proximal DVT were enrolled in this study. They were divided into the symptomatic PE group and asymptomatic PE group. RESULTS: The body weight, body mass index, thrombus size, thrombus length and location were similar in the two groups. The symptomatic PE following proximal DVT group showed an older age, higher incidence of emergency department access (85.0% vs. 38.7%, p < 0.001) and preceding infection (25.0% vs. 1.3%, p < 0.001) as well as a higher incidence of immobilization (45.0% vs 13.3%, p=0.016). In the multivariate logistic regression study, preceding infection and emergency department access showed significant association with symptomatic PE. CONCLUSION: In proximal DVT inpatients, symptomatic PE was associated with emergency department access and preceding infection. The possibility of a symptomatic PE event should be considered in proximal DVT patients, especially those who were admitted through the emergency department and had preceding infection.
Angiography ; Body Mass Index ; Body Weight ; Emergency Service, Hospital ; Fatal Outcome ; Humans ; Immobilization ; Incidence ; Inpatients ; Logistic Models ; Medical Records ; Mortality ; Prognosis ; Pulmonary Embolism* ; Retrospective Studies ; Thrombosis ; Venous Thrombosis*

BACKGROUND: Deep vein thrombosis (DVT) and pulmonary embolism (PE) are conditions with significant morbidity and mortality. Proximal DVT has a significant association with PE and possible fatal outcomes. Traditionally, PE is subdivided into symptomatic PE and asymptomatic PE, which have different treatments, preventions and prognoses. The growing utilization of computed tomography pulmonary angiography has led to increased detection of PE in DVT patients. This study examined the clinical characteristics and compared symptomatic PE and asymptomatic PE following proximal DVT.METHODS: The medical records of 258 DVT inpatients from July, 2012 to June, 2015 were reviewed retrospectively. After excluding the patients who did not performed PE evaluation and were not diagnosed with PE, 95 patients diagnosed with PE following proximal DVT were enrolled in this study. They were divided into the symptomatic PE group and asymptomatic PE group.RESULTS: The body weight, body mass index, thrombus size, thrombus length and location were similar in the two groups. The symptomatic PE following proximal DVT group showed an older age, higher incidence of emergency department access (85.0% vs. 38.7%, p < 0.001) and preceding infection (25.0% vs. 1.3%, p < 0.001) as well as a higher incidence of immobilization (45.0% vs 13.3%, p=0.016). In the multivariate logistic regression study, preceding infection and emergency department access showed significant association with symptomatic PE.CONCLUSION: In proximal DVT inpatients, symptomatic PE was associated with emergency department access and preceding infection. The possibility of a symptomatic PE event should be considered in proximal DVT patients, especially those who were admitted through the emergency department and had preceding infection.
Angiography ; Body Mass Index ; Body Weight ; Emergency Service, Hospital ; Fatal Outcome ; Humans ; Immobilization ; Incidence ; Inpatients ; Logistic Models ; Medical Records ; Mortality ; Prognosis ; Pulmonary Embolism ; Retrospective Studies ; Thrombosis ; Venous Thrombosis

PURPOSE: The aim of this study is to analyze the clinical results of using the technique of rotator cuff repair without parting the biceps long head from the glenoid for large or massive tear of the rotator cuff. MATERIAL AND METHODS: Form January 2005 to January 2007, we performed the arthroscopic biceps repair with incorporating suture to the rotator cuff for 21 patients with large or massive rotator cuff tear. The mean follow up period was 23 months (range: 6-48months). The number of males and females was 9 and 13, respectively. The age distribution ranged from 47 to 73 years with a mean age of 60.3 years. We compared the preoperative score with the postoperative scores using the University of California Los Angeles (UCLA) score, the shoulder index of the American Shoulder and Elbow Surgeons (ASES) and a simple shoulder test (SST). RESULTS: The improvement in the VAS, ASES and the UCLA and SST scores was statistically significant at the final follow up (average follow-up 23 months) (p>0.05). Two of nine cases were found to have partial tear with continuity but seven cases were found to have complete tear according to the ultrasonography and MRI. CONCLUSION: The technique of rotator cuff repair without parting the biceps long head from the glenoid for large or massive tear of the rotator cuff is considered to be recommendable.
Age Distribution ; California ; Elbow ; Female ; Follow-Up Studies ; Head ; Humans ; Los Angeles ; Male ; Rotator Cuff ; Shoulder ; Sutures ; Tendons

Parathyroid hormone (PTH) treatment was previously shown to improve cardiac function after myocardial infarction by enhancing neovascularization and cell survival. In this study, pressure overload-induced left ventricular hypertrophy (LVH) was induced in mice by transverse aortic banding (TAB) for 2 weeks. We subsequently evaluated the effects of a 2-week treatment with PTH or saline on compensated LVH. After another 4 weeks, the hearts of the mice were analyzed by echocardiography, histology, and molecular biology. Echocardiography showed that hearts of the PTH-treated mice have more severe failing phenotypes than the saline-treated mice following TAB with a greater reduction in fractional shortening and left ventricular posterior wall thickness and with a greater increase in left ventricular internal dimension. Increases in the heart weight to body weight ratio and lung weight to body weight ratio following TAB were significantly exacerbated in PTH-treated mice compared to saline-treated mice. Molecular markers for heart failure, fibrosis, and angiogenesis were also altered in accordance with more severe heart failure in the PTH-treated mice compared to the saline-treated mice following TAB. In addition, the PTH-treated hearts were manifested with increased fibrosis accompanied by an enhanced SMAD2 phosphorylation. These data suggest that the PTH treatment may accelerate the process of decompensation of LV, leading to heart failure.
Animals ; Blotting, Western ; Echocardiography ; Hypertrophy, Left Ventricular/*drug therapy/pathology ; Male ; Mice ; Mice, Inbred C57BL ; Parathyroid Hormone/pharmacology/*therapeutic use ; Phosphorylation/drug effects ; Random Allocation ; Reverse Transcriptase Polymerase Chain Reaction ; Smad2 Protein/metabolism

BACKGROUND: Recently, myeloproliferative leukemia (MPL) W515 mutations have been reported to be molecular markers for myeloproliferative neoplasms (MPNs). We studied the association between MPL W515 mutations and the clinico-hematological features of patients with MPNs. METHODS: Our study included 154 consecutive patients diagnosed with MPNs (31 had polycythemia vera [PV]; 106, essential thrombocythemia [ET]; and 17, primary myelofibrosis [PMF]). MPL W515 mutations were detected by real-time PCR and direct sequencing methods. RESULTS: The MPL W515L mutation was found in 4 patients and the MPL W515A mutation was detected in 1 patient. These 5 patients were diagnosed with JAK2 V617F-negative ET, and they accounted for 12.5% of patients with JAK2 V617F-negative ET. The patients with MPL W515-positive ET showed significantly lower hemoglobin levels and WBC counts than did patients with MPL W515-negative ET or JAK2 V617F-positive ET. CONCLUSIONS: MPL W515 mutation is a useful diagnostic marker for JAK2 V617F-negative MPNs and it is associated with specific hematologic characteristics such as lower hemoglobin levels and WBC counts.
Humans ; Janus Kinase 2 ; Leukemia ; Polycythemia Vera ; Primary Myelofibrosis ; Real-Time Polymerase Chain Reaction ; Thrombocythemia, Essential