Normal 2-Dimensional Strain Values of the Left Ventricle: A Substudy of the Normal Echocardiographic Measurements in Korean Population Study

BACKGROUND: It is important to understand the distribution of 2-dimensional strain values in normal population. We performed a multicenter trial to measure normal echocardiographic values in the Korean population. METHODS: This was a substudy of the Normal echOcardiogRaphic Measurements in KoreAn popuLation (NORMAL) study. Echocardiographic specialists measured frequently used echocardiographic indices in healthy people according to a standardized method at 23 different university hospitals. The strain values were analyzed from digitally stored images. RESULTS: Of a total of 1003 healthy participants in NORMAL study, 2-dimensional strain values were measured in 501 subjects (265 females, mean age 47 ± 15 years old) with echocardiographic images only by GE echocardiographic machines. Interventricular septal thickness, left ventricular (LV) posterior wall thickness, systolic and diastolic LV dimensions, and LV ejection fraction were 7.5 ± 1.0 mm, 7.4 ± 1.0 mm, 29.9 ± 2.8 mm, 48.9 ± 3.6 mm, and 62 ± 4%, respectively. LV longitudinal systolic strain (LS) values of apical 4-chamber (A4C) view, apical 3-chamber (A3C) view, apical 2-chamber (A2C) view, and LV global LS (LVGLS) were −20.1 ± 2.3, −19.9 ± 2.7, −21.2 ± 2.6, and −20.4 ± 2.2%, respectively. LV longitudinal systolic strain rate (LVLSR) values of the A4C view, A3C view, A2C view, and LV global LSR (LVGLSR) were −1.18 ± 0.18, −1.20 ± 0.21, −1.25 ± 0.21, and −1.21 ± 0.21(−s), respectively. Females had lower LVGLS (−21.2 ± 2.2% vs. −19.5 ± 1.9%, p < 0.001) and LVGLSR (−1.25 ± 0.18(−s) vs. −1.17 ± 0.15(−s), p < 0.001) values than males. CONCLUSION: We measured LV longitudinal strain and strain rate values in the normal Korean population. Since considerable gender differences were observed, normal echocardiographic cutoff values should be differentially applied based on sex.

Normal Echocardiographic Measurements in a Korean Population Study: Part II. Doppler and Tissue Doppler Imaging

BACKGROUND: Hemodynamic and functional evaluation with Doppler and tissue Doppler study as a part of comprehensive echocardiography is essential but normal reference values have never been reported from Korean normal population especially according to age and sex. METHODS: Using Normal echOcaRdiographic Measurements in a KoreAn popuLation study subjects, we obtained normal reference values for Doppler and tissue Doppler echocardiography including tricuspid annular velocities according to current guidelines and compared values according to gender and age groups. RESULTS: Mitral early diastolic (E) and late diastolic (A) velocity as well as E/A ratio were significantly higher in women compared to those in men. Conversely, mitral peak systolic and late diastolic annular velocity in both septal and lateral mitral annulus were significantly lower in women compared to those in men. However, there were no significant differences in both septal and lateral mitral early diastolic annular (e') velocity between men and women. In both men and women, mitral E velocity and its deceleration time as well as both E/A and E/e' ratio considerably increased with age. There were no significant differences in tricuspid inflow velocities and tricuspid lateral annular velocities between men and women except e' velocity, which was significantly higher in women compared to that in men. However, changes in both tricuspid inflow and lateral annular velocities according to age were similar to those in mitral velocities. CONCLUSION: Since there were significant differences in Doppler and tissue Doppler echocardiographic variables between men and women and changes according to age were even more considerable in both gender groups, normal Doppler echocardiographic values should be differentially applied based on age and sex.

Normal Echocardiographic Measurements in a Korean Population Study: Part I. Cardiac Chamber and Great Artery Evaluation

BACKGROUND: Measurement of the cardiac chamber is essential, and current guidelines recommend measuring and reporting values for both sides of the cardiac chamber during echocardiographic evaluation. Normal echocardiographic reference values have been suggested previously, but detailed information about right-sided chambers and values according to gender was not included. METHODS: This is a prospective multicenter (23 centers) study evaluating normal Korean adult subjects using comprehensive echocardiography. We included normal adult subjects (age; 20-79 years old) who had no significant cardiac disorders or illnesses, such as hypertension or diabetes, which could affect cardiac structure and function. We measured the cardiac chamber including both right and left ventricles as well as atria according to current echocardiography guidelines and compared values according to gender and age groups. RESULTS: A total of 1003 subjects were evaluated and the mean age was 48 +/- 16 years. Left ventricular (LV) dimensions increased, but LV volume decreased in older subjects. Right ventricular (RV) area decreased in women and older subjects, and the RV long-axis dimension showed a similar trend. Left atrial (LA) volume increased in men but there were no differences in LA volume index between men and women. The dimension of great arteries increased in men and older subjects. CONCLUSION: Since there were considerable differences between men and women and in the different age groups, and the trends differed significantly between different echo variables, normal echocardiographic cutoff values should be differentially applied based on age and gender.

Erratum to: Effect of High Dose Rosuvastatin Loading before Primary Percutaneous Coronary Intervention on Infarct Size in Patients with ST-Segment Elevation Myocardial Infarction

On page 76, reference no. 21 was inadvertently omitted.

Effect of High Dose Rosuvastatin Loading before Primary Percutaneous Coronary Intervention on Infarct Size in Patients with ST-Segment Elevation Myocardial Infarction

BACKGROUND AND OBJECTIVES: High dose rosuvastatin loading before percutaneous coronary interventions (PCI) reduces the myocardial damage and the incidence of adverse cardiac events in patients with stable angina and acute coronary syndrome. However, no studies are present yet about rosuvastatin loading in patients with ST-segment elevation myocardial infarction (STEMI) in a primary PCI setting. SUBJECTS AND METHODS: A total of 475 patients who underwent primary PCI for STEMI were studied. The study population was divided into two groups with 208 patients in the statin group=40 mg rosuvastatin loading before primary PCI and 267 patients in the control group=no statin pretreatment. At median 3 days after PCI a single-photon emission computed tomography (SPECT) was performed with technetium 99m tetrofosmin For this study were compared infarct size, corrected Thrombolysis in Myocardial Infarction (TIMI) frame count and the myocardial blush grade (MBG) between the both groups. RESULTS: Baseline clinical and procedural characteristics were similar between the groups. Infarct size, as assessed by SPECT, was significantly smaller (19.0+/-15.9% vs. 22.9+/-16.5%, p=0.009) in the statin group than in the control group. Patients of the statin group showed a lower corrected TIMI frame count (28.2+/-19.3 vs. 32.6+/-21.4, p=0.020), and higher MBG (2.49+/-0.76 vs. 2.23+/-0.96, p=0.001) than the patients of the control group. The multivariate analysis revealed that rosuvastatin loading {odds ratio (OR) 0.61}, pain to balloon time (OR 2.05), anterior myocardial infarction (OR 3.89) and final the MBG (OR 2.93) were independent predictors of a large infarct size. CONCLUSION: A high dose rosuvastatin loading before the primary PCI reduced the infarct size by microvascular myocardial perfusion improvement.

Long-Term Predictors of Clinical Events after Off-Label Use of Drug-Eluting Stent beyond 1 Year

BACKGROUND AND OBJECTIVES: We evaluated the long-term outcomes and predictors of clinical events after off-label use of drug-eluting stents (DES) beyond 1 year after procedure. SUBJECTS AND METHODS: A total of 518 patients who underwent DES implantation for off-label indications and did not have any major adverse cardiac events (MACE) during the first year were analyzed. The occurrence of MACE, including cardiac death, myocardial infarction (MI), stent thrombosis and target vessel revascularization, were evaluated for a median 1179 days (interquartile range 769-1541) after the first year. RESULTS: Major adverse cardiac events occurred in 43 patients (8.3%) including 8 cases (1.5%) of cardiac death, 9 cases (1.7%) of MI, 24 cases (4.6%) of target vessel revascularization, and 11 cases (2.1%) of stent thrombosis. Patients with MACE had a higher serum creatinine level, higher incidence of in-stent restenosis lesion, more overlapping stents, a greater number of stents, and longer stents than did patients without MACE. Multivariate analysis revealed that serum creatinine level >1.5 mg/dL {hazard ratio (HR) 2.3, p=0.019}, stent length >33 mm (HR 2.4, p=0.035), and in-stent restenosis lesions (HR 2.4, p=0.040) were independent risk factors for MACE. Patients with DES length >33 mm had a higher incidence of MACE than those with DES length 33 mm was a significant procedural predictor associated with the incidence of MACE.

Alteration of p62/SQSTM1 Expression Is Uncommon in Gastrointestinal and Prostate Cancer Tissues

No abstract available.

The Number of Endothelial Progenitor Cells is Decreased in Patients With Non-Dipper Hypertension

BACKGROUND AND OBJECTIVES: Circulating endothelial progenitor cells (EPCs) play a key role in the maintenance of endothelial homeostasis and promote vascular repair. A reduced number of EPCs and the functional activity have been associated with several cardiovascular risk factors. However, the relationship between the number of EPCs and circadian rhythm of the blood pressure (BP) remains unclear. The purpose of the present study was to evaluate the relationship between the circadian rhythm of the BP and EPCs in patients with essential hypertension. SUBJECTS AND METHODS: A total of 45 patients with essential hypertension who were newly identified by outpatient BP measurements, underwent 24-hour ambulatory BP monitoring. Among the 45 patients with essential hypertension, 20 were classified as dippers (12 men and 8 women; mean age 48+/-14 years) and 25 as non-dippers (14 men and 11 women; mean age 52+/-18 years). The EPC count was isolated from the peripheral bloodstream and quantified by flow cytometry. RESULTS: The baseline clinical characteristics were similar between the dipper and non-dipper hypertensive patients. The circulating EPCs were statistically reduced in the non-dipper patients as compared to the dippers (104+/-60 vs. 66+/-47 EPCs per 106 mononuclear cells, p=0.027). The circulating EPC level correlated positively with the circadian changes in the systolic and diastolic BP (r=0.435, p=0.003, and r=0.310, p=0.038, respectively). CONCLUSION: The present study demonstrated that the EPC count was reduced in the peripheral bloodstream in non-dipper hypertensive patients.

Significance of Resting Heart Rate in Chronic Heart Failure: Data from Cardiac Insufficiency of Various Origin in Jeonbuk (CION-J) Registry

BACKGROUND: Chronic heart failure (HF) is a leading cause of morbidity and mortality in industrialized countries. Raised resting heart rate (HR) is a marker of cardiovascular risk in general population, as well as in patients with hypertension and coronary artery disease. We studied the association between HR and cardiovascular events in patients with Cardiac Insufficiency of Various Origin in Jeonbuk (CION-J) registry. METHODS: CION-J registry was a multicenter, prospective database for chronic HF. From January 2010 to December 2010, 356 HF patients who clinically stabilized at least 2 weeks were analyzed. According to resting HR, the patients divided into the tertile (lower tertile 80/min, n = 113). Clinical outcomes during 6-month period were compared by resting HR. RESULTS: Patients with upper tertile revealed higher New York Heart Association (NYHA) class than in those with lower tertile. From the lower to the upper tertile, the incidence of composite events of death, non-fatal myocardial infarction, ischemic stroke, and hospitalization for HF were increased(3.1%, 4.4%, 16.8%, respectively; p 80/min, and ejection fraction 80/min) is a prognostic factor in chronic HF. Optimal treatment to reduce HR should be emphasized to improve prognosis of HF.

Effect of Previous Statin Therapy in Patients With Acute Coronary Syndrome and Percutaneous Coronary Intervention

BACKGROUND AND OBJECTIVES: Statin therapy after percutaneous coronary intervention (PCI) has been associated with reduced major adverse cardiovascular events (MACE). However, it has been less clear as to whether statin therapy before acute coronary syndrome (ACS) is beneficial. We studied the effect of previous statin therapy, initiated > or =1 month before PCI, on the outcome of patients with ACS who had undergone early invasive strategies. SUBJECTS AND METHODS: We stratified 479 consecutive patients with ACS who had undergone PCI, according to preprocedural statin administration as follows: previous statin-treated patients (statin group, n=237) and statin-naive patients (control group, n=242). The incidence of periprocedural myocardial infarction (MI) and in-hospital MACE was assessed. RESULTS: The incidence of Braunwald class III angina and MI presentation were significantly lower in the statin group than in the control group. Angiographic and procedural characteristics were similar between the two groups; however, slow/no reflow phenomenon occurred more frequently in the control group. After PCI, the incidence of periprocedural MI was higher in the control group than in the statin group (6.6% vs. 2.1%, p=0.016). Multivariate analysis revealed that no prior use of statin {odds ratio (OR)=2.8; 95% confidence interval (CI)=1.1-7.2; p=0.038), procedural complication (OR=4.0; 95% CI=1.5-10.5; p=0.004), stent overlap (OR=4.7; 95% CI=1.3-16.4; p=0.015), and old age (OR=3.2; 95% CI=1.2-8.0; p=0.016) were independent predictors for in-hospital MACE. CONCLUSION: Previous statin therapy before ACS was associated with milder clinical presentation and lower incidence of in-hospital MACE after early invasive strategies. The beneficial outcome is attributable to a significant reduction in periprocedural MI after PCI.

A Frameshift Mutation of the Pro-Apoptotic VDAC1 Gene in Cancers with Microsatellite Instability

No abstract available.

Left Ventricular Thrombus Associated with Takotsubo Cardiomyopathy: A Cardioembolic Cause of Cerebral Infarction

Takotsubo cardiomyopathy, also called stress-induced cardiomyopathy, usually occurs in patients with severe emotional or physiologic stress. The prognosis is favorable, and the wall motion abnormlities normalize within weeks. However, stress-induced cardiomyopathy is rarely assosicated with left ventricular thrombus and thromboembolic complications. Here, we report a case of stress-induced cardiomyopathy with left ventricular thrombus that embolized to cause cerebral infarction.

Mutational and Expressional Analysis of DOK2 Gene in Non-small Cell Lung Cancers

PURPOSE: Mounting evidence indicates that perturbation of tyrosine phosphorylation is implicated in the development of many human diseases, including cancers. Docking proteins (DOKs) are tyrosine-phosphorylated proteins that negatively regulate tyrosine kinase signaling and they are considered to be tumor suppressors. Deletion and the altered expression of the DOK2 gene have been studied in leukemias and lung cancers. However, the somatic mutation status of the DOK2 gene has not been studied in lung cancers. The aim of this study was to see whether alterations of DOK2 protein expression and somatic mutation of the DOK2 gene are present in human non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: We analyzed DOK2 somatic mutation in 45 NSCLCs (23 adenocarcinomas (AD) and 22 squamous cell carcinomas (SCC) by single-strand conformation polymorphism (SSCP). We examined the DOK2 protein expression in 45 NSCLCs by immunohistochemistry. RESULTS: SSCP analysis revealed no evidence of somatic mutation in the DNA sequences encoding the DOK2 gene in the 45 NSCLCs. Among the informative cases, 27% and 21% of the ADs and SCCs showed allelic loss in the DOK2 locus, respectively. On the immunohistochemistry, DOK2 protein was expressed in the normal bronchial epithelial cells, while it was lost in 10 (22%) of the NSCLCs. CONCLUSION: Our data indicates that DOK2 is altered in NSCLC at the expressional level, but not at the mutational level. The data also suggests that loss of the expression of DOK2 might play roles in NSCLC development by possibly altering tyrosine kinase signaling.

Copy Number Alterations of BCAS1 in Squamous Cell Carcinomas

BACKGROUND: Breast carcinoma amplified sequence 1 (BCAS1), located in 20q13, is amplified and overexpressed in breast cancers. Even though BCAS1 is expected to be an oncogene candidate, its contribution to tumorigenesis and copy number status in other malignancies is not reported. To elucidate the role of BCAS1 in squamous cell carcinomas, we investigated the copy number status and expression level of BCAS1 in several squamous cell carcinoma cell lines, normal keratinocytes and primary tumors. METHODS: We quantitated BCAS1 gene by real-time polymerase chain reaction (PCR). Expression level of BCAS1 was measured by real-time reverse transcription-PCR and immunoblot. RESULTS: Seven (88%) of 8 squamous cell carcinoma cell lines showed copy number gain of BCAS1 with various degrees. BCAS1 gene in primary tumors (73%) also showed copy number gain. However, expression level did not show a linear correlation with copy number changes. CONCLUSIONS: We identified copy number gain of BCAS1 in squamous cell carcinomas. Due to lack of linear correlation between copy numbers of BCAS1 and its expression level, we could not confirm that the overexpression of BCAS1 is a common finding in squamous cell carcinoma cell lines. However, this study shows that the copy number gain of BCAS1 is a common finding in squamous cell carcinomas.

Effect of Zoledronic Acid on Early Osseointegration of Porous Implant in Rabbit / 대한정형외과연구학회지

PURPOSE: The purpose of this study was to determine whether intravenous injection of the zoledronic acid could promote osseointegration of the porous implant inserted into the rabbit medullary cavity. MATERIALS AND METHODS: A rabbit intramedullary osseointegration model was used. A specially designed porous nitinol implant (Bio-Smart, Sungnam, Gyeonggi-do, Korea) was inserted in the right distal femur of twenty six rabbits. They were randomized into the control or the experimental groups. In the control group, an intravenous injection of normal saline 2 ml/kg (Daihan Pharm, Seoul, Korea) was given at the end of the operation. In the experimental group, an intravenous injection of zoledronic acid 0.1 mg/kg (AclastaG(R) 2 ml/kg, Norvatis, Stein, Switzerland) was given at the end of the operation. Six weeks later, all animals were sacrificed and undecalcified histologic sections were prepared. Then, histomorphometric measurement of bone affinity index (%) and bone ingrowth area rate (%) was carried out. RESULTS: Six rabbits were excluded due to death and wound infection. Nine rabbits in the control group and eleven rabbits in the experimental group were included for the analysis. The bone affinity indices were 19.9+/-7.9% in the control group, and 28.4+/-7.2% in the experimental group. Although there was no statistical significance (p=0.056), the bone affinity index of the experimental group was higher than that of the control group. The bone ingrowth area rates were 8.7+/-3.7% in the control group, and 12.1+/-4.1% in the experimental group (p=0.046), indicating zoledronic acid had an positive effect on the promotion of bone ingrowth into the porous implant. CONCLUSION: In our rabbit intramedullary osseointegration model, intravenous injection of the zoledronic acid promoted early osseointegration of the porous implant. Zoledronic acid might be useful to promote the early osseointegration of the joint replacement implants.

A Review on Usage and Effectiveness of e-Learning in Medical Education / 한국의학교육

E-learning is recently considered as a critical strategy to improve the effectiveness and efficiency of education. Although the use of e-learning has been growing rapidly in medical education, there are not sufficient data applying e-learning and evidence of the effectiveness. The purpose of the study is to review the recent literatures on applying e-learning in medical education settings and to identify usage types and educational effectiveness appeared in the research. The results demonstrated the types applying e-learning in medical education were categorized into the blended learning, online education, and virtual learning environment. The educational effectiveness of e-learning were the improvements of knowledge, clinical skill, attitude, and satisfaction. The study suggested the recommendations based on the results in order to apply e-learning effectively to medical education.

Frameshift Mutation of MARS Gene Encoding an Aminoacyl-tRNA Synthetase in Gastric and Colorectal Carcinomas with Microsatellite Instability

No abstract available.

Mutation and Expression of DNA2 Gene in Gastric and Colorectal Carcinomas

BACKGROUND: Deregulation of DNA repair and replication are involved in cancer development. DNA2 is a nuclease/helicase that plays roles in DNA repair and replication. The aim of this study was to explore DNA2 mutation and DNA2 protein expression in gastric cancers (GCs) and colorectal cancers (CRCs). METHODS: We analyzed two mononucleotide repeats in DNA2 in 27 GCs with high microsatellite instability (MSI-H), 34 GCs with stable MSI (MSS), 29 CRCs with MSI-H and 35 CRCs with MSS by single-strand conformation polymorphism. We also analyzed DNA2 expression in GCs and CRCs either with MSI-H or MSS. RESULTS: We found DNA2 mutations in two GCs (7.1%) and two CRCs with MSI-H (6.9%), but not in cancers with MSS. The mutations consisted of three cases of a c.2593delT and one of a c.2592_2593delTT, which would result in premature stopping of amino acid synthesis (p.Ser865Hisfsx6 and p.Ser865Thrfsx20, respectively). DNA2 expression was observed in 16 (80%) of the GCs and 15 (75%) of the CRCs with MSI-H, but all of the cancers with DNA2 frameshift mutations were weak or negative for DNA2. CONCLUSIONS: Our data indicate that DNA2 mutation and loss of DNA2 expression occur in GCs and CRCs, and suggest that these alterations may contribute to cancer pathogenesis by deregulating DNA repair and replication.

Perception of Medical Students on Real-Time Class Evaluation Using Mobile Phone Survey System / 한국의학교육

PURPOSE: The aim of this study is to investigate the advantage of real-time class evaluation over course evaluation in integrated courses and to explore the usefulness and availability of a mobile phone survey system as a real-time class evaluation tool. METHODS: In six integrated courses at the preclinical second year both course and class evaluations were performed. Class evaluations were carried out 206 times right after every class by a mobile phone survey system that depended on mobile phones to send information. A survey was performed to identify students' perception on real-time class evaluation and the mobile phone survey system. RESULTS: The course evaluation score was found to have greater than 95% confidence interval of class evaluations at 5 of 6 courses. Class evaluations yielded more information on educational content and teaching strategy than course evaluations. A higher score was given in class evaluation regarding effectiveness on improving quality of education (3.77 vs. 2.15) and sincerity during evaluation (3.87 vs. 2.49). Of the three major evaluation tools, such as paper, web and mobile phone, majority of students preferred mobile phones especially in terms of accessibility (89%), familiarity (75.3%), and time (74%). CONCLUSION: In integrated courses, real-time class evaluations could yield more information and better sincerity than course evaluations. Real-time class evaluations could be successfully performed through a mobile phone survey system compared with that of paper- or web-based methods.

Methods of Effective Team-Based Learning Administration and Expected Effects on Medical Education / 한국의학교육

PURPOSE: The aim of this study was to analyze the results of quantitative and qualitative student evaluations of team-based learning (TBL) and student achievement evaluations during TBL. METHODS: Questionnaires that evaluated medical student perception and self-assessment of the TBL experience included 38 questions on the TBL process. Also, we used scores from the TBL session to investigate student academic achievement. RESULTS: Our results showed that the more proper the educational environments were, the more focused students were on team learning. According to the distribution period for preliminary assignments, there was a difference in self-directed learning. In addition, team members had the opportunity to learn new knowledge by interacting with each other, and when they had the experience of feedback, they understood the instruction topics through team learning better. With regard to peer evaluation, the students who recognized the importance of assessment studied more sincerely and honestly. By experiencing the TBL process, every team showed a high significance in the group readiness assurance test score compared with the individual readiness assurance test score, and student satisfaction with the TBL and expectation levels about capacity strengthening increased as well. CONCLUSION: TBL is an effective teaching and learning method and has positive impacts on student academic achievement. A study on student academic achievement and perception of TBL is expected to provide medical educators with suggestions on planning teaching strategies for effective TBL administration.