Lipoprotein-Associated Phospholipase A2 Is Related to Plaque Stability and Is a Potential Biomarker for Acute Coronary Syndrome

PURPOSE: Plasma lipoprotein-associated phospholipase A2 (Lp-PLA2) binds to low-density lipoprotein. The levels of Lp-PLA2 reflect the plaque burden, and are upregulated in acute coronary syndrome (ACS). We investigated the diagnostic value of Lp-PLA2 levels and found that it might be a potential biomarker for ACS. MATERIALS AND METHODS: We classified 226 study participants into three groups: patients without significant stenosis (control group), patients with significant stenosis with stable angina (SA group), and patients with ACS (ACS group). RESULTS: Lp-PLA2 and high-sensitivity C-reactive protein (hs-CRP) levels were significantly greater in the ACS group than in the SA group (p=0.044 and p=0.029, respectively). Multivariate logistic regression analysis revealed that Lp-PLA2 levels are significantly associated with ACS (odds ratio=1.047, p=0.013). The addition of Lp-PLA2 to the ACS model significantly increased the global chi2 value over traditional risk factors (28.14 to 35.602, p=0.006). The area under the receiver operating characteristic curve for Lp-PLA2 was 0.624 (p=0.004). The addition of Lp-PLA2 level to serum hs-CRP concentration yielded an integrated discrimination improvement of 0.0368 (p=0.0093, standard error: 0.0142) and improved the ability to diagnose ACS. CONCLUSION: Lp-PLA2 levels are related to plaque stability and might be a diagnostic biomarker for ACS.

Significance of Small Dense Low-Density Lipoprotein as a Risk Factor for Coronary Artery Disease and Acute Coronary Syndrome

Small dense LDL (sd-LDL) has recently emerged as an important coronary artery disease (CAD) risk factor. This study was performed to investigate how LDL particle size is related to CAD and acute coronary syndrome (ACS). Blood samples were collected from 504 patients that underwent coronary angiography to evaluate chest pain. The LDL particle size of these samples was measured. The mean LDL particle size was smaller in patients with angiographically proven CAD than in the controls (26.41+/-0.95 vs 26.73+/-0.64nm, p < 0.001), and was negatively correlated with the Framingham risk score (r=-0.121, p=0.007). Patients with more extensive CAD had smaller LDL particles. LDL particle size was also smaller in patients with acute coronary syndrome as compared to non-ACS patients (26.09+/-1.42 vs 26.54+/-0.63nm, p=0.011). These results suggest that sd-LDL is independently associated with the incidence and extent of CAD, and can be a risk factor for the development of ACS in the Korean population.

Ex Vivo Generation of RBCs from CD34+ Cells in Human Umbilical Cord Blood and Expression Profile Analysis Using Microarray / 대한진단검사의학회지

BACKGROUND: In this study, we attempted to generate RBCs from CD34+ cells in cord blood using a 3-step culture protocol and also evaluated a change in immunophenotypic characteristics and expression profile according to erythropoietin (EPO) concentrations and culture duration. METHODS: Using mini-MACS columns, CD34+ cells were isolated from cord blood. The culture procedure comprised three steps. For each step, cells were cultured sequentially for 7 days in a serum free liquid medium with a specific combination of growth factors for 21 days. [1st step: Flt3-ligand (Flt3-L), thrombopoietin and stem cell factor (SCF); 2nd step: IGF-1, SCF and EPO; and 3rd step: IGF-1 and EPO] To evaluate the effect of EPO on proliferation and differentiation, cells were cultured with different EPO concentrations (0, 3, 10 & 20 U/mL). Cell count and morphology were monitored during the culture. For phenotyping, antibodies to CD34, CD38, CD45 and glycophorin A (GPA) were used. The expression profile of cultured cells was analyzed by 17, 000-gene microarray analysis. RESULTS: As EPO concentration increased, cell expansion was also increased, showing a maximum expansion at 20 U/mL. The cell population showed a gradual decrease in expression of CD34 and CD45, whereas the expression of GPA was not prominent in any conditions. However, we observed increased expression in some genes associated with erythropoiesis (e.g. glycophorin A, rhesus blood group CcEe antigens). CONCLUSIONS: This study shows that erythropoietin enhances the proliferation of hematopoietic progenitor cells. Our culture system did not achieve pure production of RBCs, but induced expression changes that indicated erythroid differentiation.

The Hepatopulmonary Syndrome

No abstract available.

Cardiac Involvement in Patients with Duchenne Muscular Dystrophy

BACKGROUND: Cardiac involvement in Duchenne muscular dystrophy (DMD) is common, but usually latent without symptoms or signs in the initial period of disease. This study investigated the incidence and predictor of cardiac involvement in DMD patients. METHOD: From January 2000 to June 2005, we enrolled 45 patients with DMD (aged 20.2+/-3.0 years) who admitted to the Yongdong Severance Hospital. Electrocardiography and transthoracic echocardiography was done to evaluate the cardiac function. RESULT: Electrocardiographic abnormalities were present in 80.1% of patients. Sinus tachycardia was most common (50%). LVEF was decreased (46.7+/-13.8%), and 56% of the patients had diastolic dysfunction. Patients with pulmonary involvement were older (20.7+/-3.8 vs 17.6+/-2.8 years, p=0.028), and patients with reduced LVEF (<50%) had longer duration of disease (11.4+/-4.4 vs 14.3+/-2.4 years, p=0.04). However, on multivariate analysis, age, duration of disease, pulmonary involvement, dyspnea symptom, electrocardiographic abnormality was not an independent predictor for LV systolic dysfunction in adolescent and adult patients with DMD. CONCLUSION: Cardiac involvement in adolescent and adult patients with DMD was frequently observed independent of age, duration of disease, pulmonary involvement, and dyspnea symptom. Therefore, more active cardiac investigation is required in patients with DMD, even without clinical suspicion.