Changes in Strain Pattern and Exercise Capacity after Transcatheter Closure of Atrial Septal Defects

BACKGROUND AND OBJECTIVES: Assessment of left ventricle (LV) function by using strain and strain rate is popular in the clinical setting. However, the use of these echocardiographic tools in assessing right ventricle (RV) failure, and the manner in which they both reflect the functional capacity of the patient, remains poorly understood. This study aimed to investigate the change in exercise capacity and strain between before and (1 month) after the transcatheter closure of atrial septal defects (ASDs). SUBJECTS AND METHODS: Thirty patients who underwent transcatheter closure of ASD between May 2014 and June 2015 at the Division of Pediatric Cardiology, Severance Cardiovascular Hospital, were enrolled. We compared and analyzed the results of the following examinations, before and (1 month) after the procedure: echocardiography, cardiopulmonary exercise test (CPET), and N-terminal pro-brain natriuretic peptide level. RESULTS: There were no mortalities, and the male-to-female ratio was 1:2. The mean defect size was 22.3±4.9 mm; the mean Qp/Qs ratio, 2.1±0.5; and the mean device size, 22.3±4.9 mm. Changes in global RV longitudinal (GRVL) strain and LV torsion were measured echocardiographically. Exercise capacity improved from 7.7±1.2 to 8.7±1.8 metabolic equivalents (p=0.001). These findings correlated to the change in GRVL strain (p=0.03). CONCLUSION: The average exercise capacity increased after device closure of ASD. The change in strain was evident on echocardiography, especially for GRVL strain and LV torsion. Further studies comparing CPET and strain in various patients may show increased exercise capacity in patients with improved RV function.

Microbubbles used for contrast enhanced ultrasound and theragnosis: a review of principles to applications

Ultrasound was developed several decades ago as a useful imaging modality, and it became the second most popular diagnostic tool due to its non-invasiveness, real-time capabilities, and safety. Additionally, ultrasound has been used as a therapeutic tool with several therapeutic agents and in nanomedicine. Ultrasound imaging is often used to diagnose many types of cancers, including breast, stomach, and thyroid cancers. In addition, ultrasound-mediated therapy is used in cases of joint inflammation, rheumatoid arthritis, and osteoarthritis. Microbubbles, when used as ultrasound contrast agents, can act as echo-enhancers and therapeutic agents, and they can play an essential role in ultrasound imaging and ultrasound-mediated therapy. Recently, various types of ultrasound contrast agents made of lipid, polymer, and protein shells have been used. Air, nitrogen, and perfluorocarbon are usually included in the core of the microbubbles to enhance ultrasound imaging, and therapeutic drugs are conjugated and loaded onto the surface or into the core of the microbubbles, depending on the purpose and properties of the substance. Many research groups have utilized ultrasound contrast agents to enhance the imaging signal in blood vessels or tissues and to overcome the blood–brain barrier or blood-retina barrier. These agents are also used to help treat diseases in various regions or systems of the body, such as the cardiovascular system, or as a cancer treatment. In addition, with the introduction of targeted moiety and multiple functional groups, ultrasound contrast agents are expected to have a potential future in ultrasound imaging and therapy. In this paper, we briefly review the principles of ultrasound and introduce the underlying theory, applications, limitations, and future perspectives of ultrasound contrast agents.

Reliability and Validity of the Korean Version of the Post-Traumatic Stress Disorder Checklist in Public Firefighters and Rescue Workers

OBJECTIVES: Firefighters and rescue workers are likely to be exposed to a variety of traumatic events; as such, they are vulnerable to the risk of post-traumatic stress disorder (PTSD). The psychometric properties of the Korean version of the PTSD Checklist (PCL), a widely used self-report screening tool for PTSD, were assessed in South Korean firefighters and rescue workers. METHODS: Data were collected via self-report questionnaires and semi-structured clinical interviews administered to 221 firefighters. Internal consistency, item-total correlation, one-week test-retest reliability, convergent validity, and divergent validity were examined. Content validity of the PCL was evaluated using factor analysis and receiver operating characteristic (ROC) analyses were used to estimate the optimal cutoff point and area under the curve. RESULTS: The PCL demonstrated excellent internal consistency (alpha = 0.97), item-total correlation (r = 0.72-0.88), test-retest reliability (r = 0.95), and convergent and divergent validity. The total score of PCL was positively correlated with the number of traumatic events experienced (p < 0.001). Factor analysis revealed two theoretically congruent factors: re-experience/avoidance and numbing/hyperarousal. The optimal cutoff was 45 and the area under the ROC curve was 0.97. CONCLUSIONS: The Korean version of the PCL may be a useful PTSD screening instrument for firefighters and rescue workers, further maximizing opportunities for accurate PTSD diagnosis and treatment.

Effects of the Combination Herbal Extract on Working Memory and White Matter Integrity in Healthy Individuals with Subjective Memory Complaints : A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

OBJECTIVES: The combination extract of four kinds of herbs, Gastrodia elata, Liriope platyphylla, Dimocarpus longan, and Salvia miltiorrhiza, has shown to have memory improving effects in mice. The aim of this study was to investigate the efficacy and safety of the herbal mixture for improving working memory as well as microstructural changes in white matter integrity in individuals with subjective memory complaints. METHODS: Seventy-five individuals with subjective memory complaints were assigned to receive either placebo (n = 15) or herbal mixture (low-dose group, n = 30 and high-dose group, n = 30) supplementation in an 8-week, randomized, double-blind, placebo-controlled clinical trial. Changes in working memory performance and fractional anisotropy (FA) values reflecting white matter integrity from baseline to 8-week endpoint were assessed. RESULTS: The herbal mixture group showed an increase in working memory performance compared to the placebo group (p for interaction = 0.001). In addition, the herbal mixture group showed an increase in FA values in the temporo-parietal regions (corrected p < 0.05), which are crucially involved in working memory function and are among the most affected regions in patients with cognitive impairments. CONCLUSIONS: Findings from this study indicate that the herbal mixture may be a promising therapeutic option for individuals with subjective memory complaints.

Effects of Korean Red Ginseng on White Matter Microstructure and Cognitive Functions: A Focus on Intrusion Errors

OBJECTIVES: Although ginseng has been reported to protect neuronal cells and improve various cognitive functions, relationship between ginseng supplementation and response inhibition, one of the important cognitive domains has not been explored. In addition, effects of ginseng on in vivo human brain have not been investigated using the diffusion tensor imaging (DTI). The purpose of the current study is to investigate changes in intrusion errors and white matter microstructure after Korean Red Ginseng supplementation using standardized neuropsychological tests and DTI. METHODS: Fifty-one healthy participants were randomly allocated to the Korean Red Ginseng (n = 26) or placebo (n = 25) groups for 8 weeks. The California Verbal Learning Test was used to assess the number of intrusion errors. Intelligence quotient (IQ) was measured with the Korean Wechsler Adult Intelligence Scale. Depressive and anxiety symptoms were evaluated using Hamilton Depression Rating Scale, Hamilton Anxiety Rating Scale, and Hopkins Symptom Checklist-25. The fractional anisotropy (FA) was measured from the brain DTI data. RESULTS: After the 8-week intervention, Korean Red Ginseng supplementation significantly reduced intrusion errors after adjusting age, sex, IQ, and baseline score of the intrusion errors (p for interaction = 0.005). Change in FA values in the left anterior corona radiata was greater in the Korean Red Ginseng group compared to the placebo group (t = 4.29, p = 0.04). CONCLUSIONS: Korean Red Ginseng supplementation may be efficacious for improving response inhibition and white matter microstructure integrity in the prefrontal cortex.

Sex Differences in Cerebellar Structure of Healthy Adults

OBJECTIVES: Although there have been studies that examine sex differences of the brain structures using magnetic resonance imaging, studies that specifically investigate cerebellar structural differences between men and women are scarce. The purpose of current study was to examine sex differences in structures of the cerebellum using cerebellar template and cerebellum analysis methods. METHODS: Sixteen men and twenty women were included in the study. A MATLAB based program (MathWorks, Natick, MA, USA), Statistical Parametric Mapping 5 (SPM5) using the spatially unbiased infra-tentorial atlas template (SUIT) as the cerebellum template, was used to analyze the brain imaging data. RESULTS: There was no significant difference in age between men (mean age = 28.1) and women (mean age = 27.2). Men showed higher gray matter density than women in two left cerebellar areas including the clusters in the lobules IV and V (a cluster located across the lobules IV and V), and the lobule VIIIb (lobules IV and V, t = 4.75, p < 0.001 ; lobule VIIIb, t = 3.08, p = 0.004). CONCLUSIONS: The current study found differences in cerebellar gray matter density between men and women. The current study holds its significance for applying the template specifically developed for the analysis of cerebellum.

cDNA Microarray Experiment: Design Issues in Early Stage and the Need of Normalization / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The cDNA microarray has become a useful tool for observing the expression of thousands of genes simultaneously. However, obtaining good quality microarray data is not easy due to the inherent noise at various stages of the experiment. Therefore, it is essential to understand the source of the variation in the microarray experiment and its size as an initial step of the data analyses. MATERIALS AND METHODS: The total RNA extracted from HT-1080 fibrosarcoma and normal rat tissues were hybridized to the cDNA microarrays with 0.5 K human and 5 K rat genes, respectively. A homotypic reaction and dye swap experiments were used to identify the sources of the variation. RESULTS: The relative fluorescent intensities of the microarray, if unnormalized, have a large variation, particularly in the lower intensity region. The distribution of the log intensity ratios also exhibit some departure from a band around zero, which is the distribution pattern expected when the majority of genes in the microarray are not regulated. Normalization of the log ratios is usually required as a means of preprocessing the data. We claim that a within-print tip group, an intensity-dependent normalization through a loess fit adjustment will be useful for this purpose, particularly in the initial stages of the microarray experiment. CONCLUSION: For proper data analysis, an understanding the source of the variation and preprocessing of data with a suitable normalization method will be important. It is important to have an interactive cooperation between a researcher and a statistician from the early stages of the study design and to the final stages of data analysis.

Efficacy and Safety of Atorvastatin in Patients with Elevated LDL-cholesterolemia

BACKGROUND AND OBJECTIVES: HMG-CoA reductase inhibitors have been used for a decade to lower LDL cholesterol levels and to improve cardiovascular diseases and clinical outcomes. This study was designed to evaluate the clinical efficacy and safety profiles of atorvastatin, a new HMG-CoA reductase inhibitor, in patients with elevated LDL-cholesterolemia. MATERIAL AND METHODS: Eighty three patients who had high 12-hour fasting serum LDL-cholesterol level (> or =145 mg/dl and or =145 mg/dl and TG < or =400 mg/dl were assigned to receive atorvastatin 10 mg once daily for 4 weeks. After 4 weeks, the dose was continued for 4 weeks in each individual if serum LDL-cholesterol was maintained below 130 mg/dL. For each individual whose serum LDL-cholesterol was above 130 mg/dL, the dose was doubled (20 mg/day) and administered for 4 weeks. Serum AST, ALT and CPK were also measured in addition to blood chemistry tests for lipid profiles at 4 and 8 weeks for safety assessment. RESULTS: 1) The total study population who completed the whole protocol was composed of 46 patients (23 male, 23 female, mean age 54 years). 2) At 4 weeks, the reduction by mean percent change from the baseline in LDL-cholesterol was -44.8% (from 182.3+/-3.4 mg/dl to 99.7+/-2.9 mg/dl). The fixed goal of LDL-cholesterol less than 130 mg/dl was achieved by 95.8%. 3) At 4 weeks, the mean percent change from the baseline in TC, TG, HDL-C, LDL/HDL-C and ApoB were -32.3%, -17.4%, +9.6%, -48.5% and -36.6%, respectively. 4) At 8 weeks, the mean percent change from the baseline in LDL-cholesterol was -43.0% (from 182.3+/-3.4 mg/dl to 103+/-2.4 mg/dl). The fixed goal of LDL-cholesterol less than 130 mg/dl was achieved by 91.3% of the whole patients. 5) At 8 weeks, the mean percent change from the baseline in TC, TG, HDL-C, LDL/HDL-C and ApoB were -31.3%, -22.6%, +13.7%, -48.8% and -35.9%, respectively. 6) No serious side effects were observed during the whole period. CONCLUSION: Atorvastatin is highly effective and safe in modulating lipid profiles favorably (lower LDL-Cholesterol, lower TG, elevate HDL-Cholesterol), in patients with serum lipid abnormality.

A Clinical Study on Anti-Hypertensive Effect and Safety of Candesartan Cilexetil (Atacand) in Mild to Moderate Hypertensive Patients

BACKGROUND AND OBJECTIVES: Candesartan cilexetil (Atacand ), a selective type I angiotensin II receptor blocker, has recently been introduced as a new antihypertensive agent. We evaluated its anti-hypertensive effect and safety in mild to moderate hypertensive patients. MATERIALS AND METHODS: Candesartan cilexetil, 8 mg or 16 mg, was administered once a day over 8 weeks period in the patients with mild to moderate hypertension (25 male, 26 female, mean age: 53.5+/-1.2 years). For safety evaluation, laboratory tests were performed before and after treatment with candesartan cilexetil. Changes in blood pressure, heart rate and electrocardiogram were also observed. RESULTS: 1) The mean blood pressures in the sitting position were systolic 164.1+/-2.1 mmHg and diastolic 106.3+/-0.8 mmHg before treatment, which were lowered to 135.4+/-2.0 mmHg and 89.1+/-1.1 mmHg, repectively after 8 weeks of treatment (p0.05). 4) Laboratory tests revealed no significant abnormality by the treatment with candesartan cilexetil. 5) Left ventricular hypertrophy by ECG criteria detected in 3 cases disappeared after treatment with candesartan cilexetil. 6) No significant side effects were observed during the treatment period. CONCLUSION: Candesartan cilexetil, 8 mg or 16 mg, once a day is an effective and well tolerated antihypertensive treatment. It has a significant dose-dependent antihypertensive effect.