BACKGROUND: This study was designed to evaluate the role of KATP channel activation and change of monophasic action potential duration on cardioprotective effect of ischemic preconditioning in cat. METHODS: 34 cats were divided into 4 groups: control (n=10), ischemic preconditioning(n=8), glibenclamide pre-treated(n=8) and nicorandil pre-treated group(n=8). Ischemic preconditioning was done in ischemic preconditioning and glibenclamide pre-treated groups by 3 episodes of 5 min ischemia and 10 min reperfusion. All subjects underwent 40 min of ischemia and 40 min reperfusion. The KATP channel antagonist glibenclamide was given as intravenous bolus (0.5mg/kg) 10 min before ischemic precondtioning and infused (5 microgram/min) during ischemic preconditioning. Nicorandil, a KATP channel opener was injected as intravenous bolus (0.5mg/kg) before 40 min ischemic procedure. Monophasic action potential duration at 50% repolarization(MAP50) was measured in the ischemic and non-ischemic area respectively by epicardial probe throughout the experiment. The effects of ischemic preconditioning were determined by infarct size (% area at risk). RESULTS: Ischemic preconditioning or pretreatment with nicorandil prior to 40 min ischemia demonstrated a significant reduction in infarct size(26.6+/-7%, 33+/-8% infarction of the risk zone, respectively, p<0.01, p<0.05 vs. control) with respect to control(42+/-7% infarction of the risk zone). Pretreatment with glibenclamide abolished the effect of ischemic preconditioning(40+/-8% infarction of the risk zone, p=NS vs. control) Ischemic preconditioning group exhibited a significant reduction of ischemic area MAP50 duration in the ischemic area during preconditioning; at first preconditioning 123+/-9msec vs. 137+/-19msec control(p=NS), at second preconditioning 105+/-16msec vs. 140+/-19msec control(p<0.01), at third preconditioning 109+/-15msec vs. 138+/-19msec control(p<0.05). Pretreatment with glibenclamide prevented the reduction of MAP50 in the ischemic area during ischemic preconditioning. During 40 minutes ischemia, MAP50 shortening was more pronounced in the preconditioned group than in control group; at 10 min 85+/-22 msec vs. 131+/-31msec control(p<0.05), at 20 min 88+/-21msec vs. 130+/-32msec control(p<0.05), and at 30 min 103+/-24msec vs. 136+/-30msec control(p<0.05). This shortening effect was prevented by glibenclamide pretreatment. Nicorandil pretreatment pronounced the ischemic shortening of MAP50 in ischemic area and the nicorandil effect was most significant during early ischemic period; at 10 min 97+/-21msec(p<0.05 vs. control), at 20 min 104+/-32msec (p=NS vs. control), and at 30 min 134+/-28msec(p=NS vs. control). MAP50 measured in non-ischemic area was not significantly different between groups. CONCLUSION: We conclude that KATP channel activation and monophasic action potential duration shortening play a important role in myocardial protection during ischemic injury.
Action Potentials* ; Animals ; Cats* ; Glyburide ; Infarction ; Ischemia ; Ischemic Preconditioning* ; Nicorandil ; Reperfusion

As it has been reported that the depolarization-induced norepinephrine (NE) release is modulated by activation of presynaptic A-1-adenosine heteroreceptor and various lines of evidence indicate that A-2-adenosine receptor also presents in hippocampus, and that the adenosine effect is magnesium dependent, the present study was undertaken to delineate the role of adenosine receptors in the modulation of hippocampal NE release. Slices from the rat hippocampus were equilibrated with (3H)-NE and the release of the labelled product, (3H)-NE, was evoked by electrical stimulation (3 Hz, 5 V cm-1, 2 ms, rectangular pulses), and the influence of various agents on the evoked tritium outflow was investigated. N-6-cyclopentyladenosine (CPA), in concentrations ranging from 0.1 to 10 micrometer, decreased the (3H)-NE release in a dose-dependent manner without changing the basal rate of release, and these effects were significantly inhibited by 8-cyclopentyl-1,3-dipropylxanthine (DPCPX, 2 micrometer) treatment. When the magnesium concentration was reduced to 0.4 mM or completely removed, the evoked NE release increased along with decreased basal rate of release. In contrast, increasing the magnesium concentrations to 2.4 and 4 mM, decreased the evoked NE release. The CPA effects on evoked NE release were reduced by magnesium removal, but potentiated by 2.4 mM magnesium in the medium. 5-(N-cyclopropyl)-carboxamodiadenosine (CPCA, 1 & 10 micrometer), an A-2-agonist, decreased the evoked tritium outflow, and this effect was also abolished by DPCPX pretreatment. CGS, a powerful A-2-agonist, did not affect the evoked NE release. However, the effects of CPCA and CGS on evoked NE release were significantly increased by pretreatment of DPCPX in the magnesium-free medium. These results indicate that inhibitory effect of A-1-adenosine receptor on NE release is magnesium-dependent, and A-2-receptor may be present in the rat hippocampus.
Adenosine ; Animals ; Electric Stimulation ; Hippocampus* ; Magnesium* ; Norepinephrine* ; Rats* ; Receptors, Purinergic P1 ; Tritium

This survey was performed to obtain the basic information for the prevention and management of occupational low back injury(LBI). The subjects of this survey were 952 workers(male, 892;female, 60) who had taken occupational LBI in some industries of Pusan area from January 1 to December 31, 1991. Observation period was 2.6 years from the beginning to the end of medical treatment. The obtained results were summarized as follows; 1. The proportion of LBI workers was 15.9% of the workers who had taken any occupational injuries and 0.32% of all workers in this surveyed area. 2. 8.0% of the workers had taken LBI on the 1st day of employment and 55.2% of the workers were within one year, 91.4% of the workers were within 10 years according to cumulative frequency distribution. 3. Handling of heavy objects was the most common cause of LBI(32.0%) and fall down(26.9%) and slip down(16.3%) were the next in order. 4. The most common causes of both lumbar sprain and HNP were handling of heavy objects and that of lumbar fracture was fall down. 5. The mean duration for medical treatment of LBI workers was 143 days. 6. The total direct compensation cost for LBI workers was 6,736 million Won and the proportion of medical, resting, disability compensation costs were 25.0%, 37.0%, 38.0% respectively. 7. The percentages of retreated workers and disabled workers were 11.9%(113 persons) and 22.9%(218 persons) of total LBI workers respectively.
Back Injuries* ; Busan* ; Compensation and Redress ; Employment ; Occupational Injuries ; Sprains and Strains

BACKGROUND: Doppler echocardiography is widely used for the noninvasive evaluation of left ventricular diastolic function. More recently, it has attempted to indirectly assess left hemodynamic status by using different measurements obtained from puled wave Doppler ultrasound mitral flow recordings. However, the mitral flow velocity pattern is affected by several physiologic factors and change to normalized or restricutve pattern, Thus, this study designed to assess the relatioship between intraventricular dispersion of early diastolic flow velocity and hemodynamic variables. METHOD: The study population consisted of 8 patients with atypical chest pain, 8 patients with stable angina pectoris, 10 patients with myocardial infarction and 4 patients with dilated cardiomyopathy. Left ventricular catheterization was performed with fluid-filled catheter and left ventricular systolic pressure(LVSP), left ventricular end diastolic pressure(LVEL), -peak/dP/dt, and +peak dP/dt were measured, the mitral flow velocity was recorded at mitral valve tip and regional left ventricular diastolic flow velocity was recored at 1cm, 2cm and 3cm from mitral valve tip to the apex. Regional left ventricular early diastolic flow velocity was expressed as percentage to the early diastolic flow velocity in mitral valve tip(%Ex=(peak Ex/peak E)×100, %VTIEx=VTIEx/VTIE)×100, x=cm from mitral valve tip). RESULTS: There were modest negative correlations between %E2, %E3 and left ventricular end-diastolic pressure, respectively ; r=−0.62, −0.46. Modest negative correlation was found between %VTIE2 and LVEDP(r=0.42). %E2 < 70 predicted left ventricular end-diastolic pressure>15mmHg with a sensitivity of 74% and specificity of 77%. CONCLUSION: Propagation of left ventricular filling flow veolcity in early diastole is correlate with left ventricular end-diastolic pressure and %E2 is a relatively useful index of elevated left ventricular end-diastolic pressure.
Angina, Stable ; Cardiomyopathy, Dilated ; Catheterization ; Catheters ; Chest Pain ; Diastole ; Echocardiography, Doppler ; Hemodynamics ; Humans ; Methods ; Mitral Valve ; Myocardial Infarction ; Sensitivity and Specificity ; Ultrasonography

BACKGROUND: The purpose of this study was to evaluate serum lipid levels in Korean adults after consumption of different types of yogurt. METHODS: Study subjects were 3,038 individuals (≥19 years of age) who participated in the 2012 Korean National Health and Nutrition Examination Survey. Yogurt intake was assessed with a food frequency questionnaire by using the 24-hour recall method. We conducted complex samples general linear analysis with adjustment for covariates. RESULTS: The serum triglyceride levels in the group consuming viscous yogurt were lower than those in the group consuming non-viscous yogurt. CONCLUSION: Consumption of viscous yogurt is associated with low serum triglyceride levels in Korean adults.
Adult ; Cholesterol ; Humans ; Korea* ; Methods ; Nutrition Surveys* ; Triglycerides ; Yogurt*

BACKGROUND: The clinical practice examination (CPX) was introduced in 2010, and the Seoul-Gyeonggi CPX Consortium developed the patient-physician interaction (PPI) assessment tool in 2004. Both institutions use rating scales on classified sections of PPI but differ in their scoring of key components. This study investigated the accuracy of standardized patient scores across rating scales by comparing checklist methods and verified the concurrent validity of two comparable PPI rating tools. METHODS: An educational CPX module dyspepsia case was administered to 116 fourth-year medical students at Hanyang University College of Medicine. One experienced standardized patient rated exams using two different PPI scales. She scored checklists composed of 43 items related to the two original PPI scales through video clips of the same students. From these checklists, we calculated Pearson's correlation coefficient. RESULTS: The correlations of total PPI score between the checklist and rating scale methods were 0.29 for the Korean Medical Licensing Examination (KMLE) tool and 0.30 for the consortium tool. The correlations between the KMLE and consortium tools were 0.74 for checklists and 0.83 for rating scales. In terms of section scores, the consortium tool showed only three significant correlations between the two methods out of seven sections and the KMLE tool showed only two statistically significant correlations out of five sections. CONCLUSION: The rating scale and checklist methods exhibited a weak relationship in the PPI assessment, but a high correlation between assessment tools using the same method. However, the current rating scale requires modification by reorganizing key scoring components through factor analysis.
Behavior Rating Scale ; Checklist* ; Dyspepsia ; Education, Medical ; Educational Measurement ; Humans ; Licensure ; Methods ; Physician-Patient Relations ; Students, Medical ; Weights and Measures

BACKGROUND: After introduction of clinical skills assessment in the Korean Medical Licensing Examination, medical schools have reinforced both experiential learning with real patients and preparatory programs. This study was conducted to investigate whether a clinical practice examination (CPX) preparation program improves students' CPX score in terms of case specificity. METHODS: One hundred and thirteen senior students in a medical school participated in this study. During the fourth-year clerkship, 28 students (24.8%) from three rotation groups took a 3-day CPX preparation course consisting of module development, role play, and comprehensive physical exam skills training. Eleven rotation groups (n=85) were compared as control. Both the intervention and control group took two comprehensive CPXs before and after the clerkship was completed. RESULTS: There was no significant difference in age, sex, and school type between the two groups. On pre-test CPX, there was no significant difference in total and sectional scores between the two groups. On post-test CPX, total scores of the intervention group were higher than those of the control groups (69.5±4.3 vs. 67.5±4.4, P < 0.05). History taking scores were higher in intervention groups (70.0±6.0 vs. 66.0±6.6, P=0.01). The station scores of vaginal discharge with case similarity were higher in the intervention groups (73.0±6.3 vs. 68.9±9.3, P=0.03). CONCLUSION: A short CPX preparation course improved history taking ability, but its effect was greater only in a specific case, similar to the pre-course case. Whether this effect was due to the test experience or true improvement in competency requires further investigation.
Clinical Clerkship ; Clinical Competence ; Education, Medical, Undergraduate ; Humans ; Licensure ; Outcome Assessment (Health Care) ; Patient Simulation ; Problem-Based Learning ; Role Playing ; Schools, Medical ; Sensitivity and Specificity ; Simulation Training ; Vaginal Discharge

PURPOSE: To examine the prevalence of obesity in elementary school-aged children in Gwangju, and long term courses of those obese children. METHODS: We examined children aged 7 to 12 in the total number of 3,028 elementary school students consisting of 1,579 boys and 1,449 girls between 1994 and 1999. Obesity was defined as weight that exceeded the standard weight for height and sex by more than 20%(relative weight >120%). RESULTS: The prevalence of obesity was 3.4% at age 7 and 6.2% at age 12. The prevalence of obesity increased with age in both sexes. In boys, 5.7% of normal weight children at age 7 became obese at age 12. Sixty percent of mild obese children and sixty four point three percent of moderately obese children at age 7 remained obese at age 12. One hundred percent of severely obese children at age 7 remained obese at age 12. In girls, 3.1% of normal weight children at age 7 became obese at age 12. Forty seven percent of mildly obese children and fifty six point three percent of moderately obese children at age 7 remained obese at age 12. Sixty six point seven percent of severely obese children at age 7 remained obese at age 12. Above half of the obese children at age 7 remained obese at age 12. CONCLUSION: Our results suggest that prevention and treatment of obesity in elementary school children is required as early as possible.
Child ; Female ; Follow-Up Studies* ; Gwangju ; Humans ; Obesity ; Pediatric Obesity* ; Prevalence

BACKGROUND AND OBJECTIVES: Prolonged atrial conduction time and inhomogeneous electrical atrial activity have been known to be important electrophysiologic characteristics in patients with paroxysmal atrial fibrillation (PAF). Filtered P wave duration dispersion (Pdisp) is defined as the difference between the maximal and minimal filtered P wave duration of the three X, Y, Z leads of P wave signal averaged ECG (PSAECG). The purpose of this study was to determine and compare conventional PSAECG parameters with this newly developed parameter, Pdisp, for the prediction of PAF risk. SUBJECTS AND METHODS: The study population, consisting of 65 patients with PAF (Group 1) and 56 age and sex matched controls (Group 2), was further subgrouped by the presence (Group A) and absence (Group B)of organic heart disease. The PSAECG was recorded using P wave triggered SAECG and the following parameters were measured: total filtered P wave duration (TFPD), vector magnitude, RMS10, RMS20, RMS30 and Pdisp. These parameter values were compared between groups. RESULTS: TFPD and Pdisp were significantly longer in the PAF group than in the control group (121.2+/-9.7 msec versus 108.5+/-12.7 msec, p=0.005:25.2+/-11.5 msec versus 14.7+/-7.9 msec, p<0.001, respectively). The presence of organic heart disease and the size of the left atrium did not affect the result. The designation of Pdisp greater than 15 msec as the cut-off value for predicting PAF produced a sensitivity of 85% and a specificity of 75%, and was more accurate than TFPD (sensitivity 72%, specificity 66%). CONCLUSION: Pdisp might be a more accurate SAECG parameter for predicting the PAF risk than other conventional parameters.
Atrial Fibrillation* ; Electrocardiography ; Heart Atria ; Heart Diseases ; Humans ; Risk Assessment ; Sensitivity and Specificity

We report on a case of ischemic dysfunction of the sinus node as a complication after percutaneous transluminal coronary angioplasty of the distal left circumflex artery. After local thrombolytic therapy in the sinus node artery, sinus node arterial flow was re-established and sinus node function normalized over the period of a week. Our experience suggests that immediate reperfusion of a totally occluded nodal artery can be re-established. Ischemic dysfunction of the sinus node, as a complication of angioplasty, is generally transient and requires a prolonged period for recovery. Therefore the decision to implant a permanent pacemaker should be delayed for at least one week after the ischemic insult.
Urinary Plasminogen Activator/administration & dosage/*therapeutic use ; Thrombolytic Therapy/*methods ; Sinoatrial Node/*physiopathology ; Myocardial Ischemia/*complications/radiography/therapy ; Middle Aged ; Male ; Infusions, Intravenous ; Humans ; Follow-Up Studies ; Fibrinolytic Agents/administration & dosage/*therapeutic use ; Electrocardiography ; Coronary Angiography ; Arrhythmia/diagnosis/*drug therapy/etiology ; Angioplasty, Transluminal, Percutaneous Coronary/adverse effects