• Journal of Biomedical Engineering Research
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• v.10 no.2
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• pp.139-150
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• 1989

A new motor-driven blood pump for artificial heart was developed. In this blood pump, a small size, high torque brushless DC motor was used as an energy converter and the motor rolls back and forth on a circular track. This movement of the "rolling-cyliner" causes blood ejection by alternately pushing left or right polyurethane blood sacs. This moving-actuator mechanism could be eliminate two potential problems of other motor-driven artificial hearts such as large size and poor anastomosis for the implantation. Theoretical analyses on the pump efficiency, the temperature rise, and the inflow mechanism were also performed. In a series of mock circulation tests, the theoretical analyses were compared to the measured hemodynamic and mechanical values. The pump system was shown to have sufficient cardiac output (upto 9 L/min), sensitivity to preload, and mechanical stability to be tested as an implantable total artificial heart.ial heart.

• Journal of Ginseng Research
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• v.46 no.6
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• pp.809-818
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• 2022

Background: The non-saponin fraction (NSF) of Korean Red Ginseng is a powder in which saponin is eliminated from red ginseng concentrate by fractionation. In this study, we examined the effect of NSF on age-associated sarcopenia in old mice. Methods: NSF (50 or 200 mg/kg/day) was administered orally daily to young (3-6-month-old) and old (20-24-month-old) C57BL/6 J mice for 6 weeks. Body weight and grip strength were assessed once a week during the oral administration period. The gastrocnemius and quadriceps muscle were excised, and the muscle fiber size was compared through hematoxylin and eosin staining. In addition, the effect of NSF on sarcopenia and inflammation/oxidative stress-related factors in hindlimb muscles was investigated by western blotting. Flow cytometry analysis was conducted to investigate the effect of NSF on immune homeostasis. Blood samples were collected by cardiac puncture, and the serum levels of insulin-like growth factor 1, pro-inflammatory cytokines, and glutathione were evaluated. Results: NSF significantly alleviated muscle strength, mass, and also fiber size in old mice. Age-associated impairment of immune homeostasis was recovered by NSF through retaining CD11b⁺F4/80⁺ macrophages and regulating inflammatory biomarkers. NSF also decreased the age-induced expression of oxidative stress factors. Taken together, NSF showed the effect of improving sarcopenia by inhibiting low-grade chronic inflammatory/oxidative stress factors. Conclusion: NSF exhibited anti-sarcopenia effects by regulating chronic inflammation and oxidative stress in old mice. Thus, we suggest that NSF is a promising restorative agent that can be used to improve sarcopenia in the elderly as well as maintain immune homeostasis.

• Journal of Pharmacopuncture
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• v.25 no.4
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• pp.369-381
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• 2022

Objectives: Hyperlipidemia (HL) is a major cause of ischemic heart diseases. The size-limiting effect of ischemic preconditioning (IPC), a cardioprotective phenomenon, is reduced in HL, possibly because of the opening of the mitochondrial permeability transition pore (MPTP). The objective of this study is to see what effect pretreatment with Inula racemose Hook root extract (IrA) had on IPC-mediated cardioprotection on HL Wistar rat hearts. An isolated rat heart was mounted on the Langendorff heart array, and then ischemia reperfusion (I/R) and IPC cycles were performed. Atractyloside (Atr) is an MPTP opener. Methods: The animals were divided into ten groups, each consisting of six rats (n = 6), to investigate the modulation of I. racemosa Hook extract on cardioprotection by IPC in HL hearts: Sham control, I/R Control, IPC control, I/R + HL, I/R + IrA + HL, IPC + HL, IPC + NS + HL, IPC + IrA+ HL, IPC + Atr + oxidative stress, mitochondrial function, integrity, and hemodynamic parameters are evaluated for each group. Results: The present experimental data show that pretreatment with IrA reduced the LDH, CK-MB, size of myocardial infarction, content of cardiac collagen, and ventricular fibrillation in all groups of HL rat hearts. This pretreatment also reduced the oxidative stress and mitochondrial dysfunction. Inhibition of MPTP opening by Atr diminished the effect of IrA on IPC-mediated cardioprotection in HL rats. Conclusion: The study findings indicate that pretreatment with IrA e restores IPC-mediated cardioprotection in HL rats by inhibiting the MPTP opening.

• Journal of Chest Surgery
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• v.23 no.6
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• pp.1256-1262
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• 1990

Percutaneous pulmonary valvuloplasty was performed in 19 patients of congenital pulmonary valve stenosis. Pulmonary annulus diameter was estimated by cross sectional echocardiography and right ventricular cineangiography. The size of balloon dilatation catheter was chosen by the same size of the estimated pulmonary annulus in the first 3 patients and 20 \ulcorner30% greater than the annulus in the last 17 patients. After valvuloplasty a satisfactory results was obtained in most patients. Before dilatation, the right ventricular systolic pressure was 91.7 mmHg[range 58-150 mmHg] and it fell to 49.2mmHg[25-85 mmHg] after dilatation. The transvalvular gradient was 67.7 mmHg[33 \ulcorner120 mmHg] before dilatation and it fell to 23.7mmHg [5 \ulcorner62] after dilatation. Repeat cardiac catheterization has been scheduled in all patients 3 months after the initial valvuloplasty but follow up recatheterization was performed in only two patients; in one of them residual gradient of 50 mmHg was reduced to 30 mmHg by repeat valvuloplasty. The other patient showed no evidence of restenosis with transvalvular gradient of 20 mmHg The balloon used for valvuloplasty was single balloon for the first 10 cases and for the later 10 cases it was replaced by Trefoil balloon which was easier for inflation and deflation. There were no significant complications during and after the procedure. From our results, we conclude that balloon valvuloplasty for congenital pulmonary valve stenosis is the treatment of choice in most patients.

• Journal of Korean Biological Nursing Science
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• v.25 no.4
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• pp.285-294
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• 2023

Purpose: This study aimed to identify the colonization rate of carbapenem-resistant Enterobacteriaceae (CRE), the characteristics of CRE isolates, and risk factors for CRE colonization in patients transferred to the general wards of a small/medium-sized hospital. Methods: This retrospective study was conducted on patients who underwent CRE culture tests within 24 hours of admission among patients transferred to a small/medium-sized hospital. Forty-seven patients confirmed as positive for CRE were classified as belonging to the patient group. For the control group, 235 patients (five times the number of the patient group) were matched by sex, age, and diagnosis, and then selected at random. Data were analyzed using descriptive analysis and multiple logistic regression analysis. Results: The CRE colonization rate was 5% (47 out of 933 patients), and Klebsiella pneumoniae (68.0%) was the most common isolate of CRE. The positivity rate of carbapenemase-producing Enterobacteriaceae was 61.7%. The risk factors for CRE colonization included renal disease (odds ratio [OR]=4.93; 95% confidence interval [CI], 1.49-16.31), heart disease (OR=3.86; 95% CI, 1.35-11.01), indwelling urinary catheters (OR=4.43; 95% CI, 1.59-12.36), and cephalosporin antibiotic use (OR=8.57; 95% CI, 1.23-59.60). Conclusion: Having a comorbid renal or cardiac disease, an indwelling urinary catheter, or a history of exposure to cephalosporin antibiotics could be classified as risk factors for CRE colonization in patients transferred to small and medium-size hospitals. It is necessary to perform active infection control through proactive CRE culture testing of patients with risk factors.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.553-558
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• 2003

The boundary estimation problem is used to estimate the shape of organic depend on the phase of the cardiac cycle or interested in the detection of the location and size of anomalies with resistivity values different from the background tissues such as nuclear reactor. And we can use the method to solve the optimal solution such as modified Newton raphson, kalman filter, extended kalman filter, etc. But, this method consumes much time and is sensitive to the initial value and noise in the estimation of the unknown shape. In the paper, we propose that multi-layer neural networks estimate the boundary of the unknown object using Fourier coefficient. This method can be used at the real time estimation and have strong characteristics at the noise and initial value. It uses voltage change; difference the homogeneous voltage to the non-homogeneous voltage, and change of Fourier coefficient change to train multi-layer neural network. After train, we can have real time estimation using this method.

• Journal of Pharmacopuncture
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• v.10 no.3
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• pp.143-147
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• 2007

Objective To derive further studies evaluating the effectiveness of Cultured Wild Ginseng Pharmacopuncture (CWGP) Therapy on squamous cell carcinoma as a first line. Methods Three cycles (4 weeks/cycle) of CWGP were administered as a dosage of 10 ml per day. Patient was diagnosed with stage IIIB squamous cell carcinoma and refused all therapy of conventional medicine because of old age and cardiac invasion of tumor. Intensive treatment of CWGP for 3 cycles was done on the patient. Computed Topography (CT) was performed to evaluate the therapeutic efficacy. Results After the intravenous infusion of 2 cycles of CWGP, chest CT revealed the mass size and pleural invasion sustained stable disease. After the point injection of 1 cycle of CWGP, chest CT revealed progressive disease. The disease free survival rate was 1 month. Conclusion This case may provide us the possibility that CWGP offers potential benefits for patients with squamous cell lung carcinoma. But this is a single case study and further case-series research should be compensated.

• Journal of Chest Surgery
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• v.21 no.6
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• pp.979-983
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• 1988

Calcium channel blockers may prevent myocardial injury during cardioplegia and reperfusion. This study was done to evaluate the effects of diltiazem cardioplegia on myocardial protection during ischemic arrest and recovery of myocardial function after reperfusion. Four formulations of crystalloid cardioplegic solutions, GIK solution[group I, n=12], diltiazem[lug/ml GIK] in GIK solution[group II, n=7], ],diltiazem[2ug/ml GIK] in GIK solution[group III, n=6] and diltiazem[4ug/ml GIK] in GIK solution[group IV, n=6] were compared in isolated working rat heart subjected to a long period [2 hours] of hypothermic arrest with multi-dose infusion. Diltiazem cardioplegia[group II, III and IV]was found to be superior in nearly all aspects. Diltiazem cardioplegia showed faster recovery of regular rhythm and lower incidence of ventricular fibrillation than group I did. In comparing mechanical function in all experimental hearts, the mean postischemic recoveries of aortic flow, cardiac output, peak aortic pressure, stroke volume and stroke work[expressed as a percentage of its preischemic control] were significantly greater in group II, III and IV[diltiazem cardioplegia] than in group I. The infused amount of cardioplegic solution was more increased by the addition of diltiazem to GI K solution. [p < 0.01] Creatine kinase leakage tended to be lower in hearts receiving diltiazem cardioplegia, especially in group III and IV[p<0.05] than in those receiving GIK solution only[group I]. Diltiazem cardioplegia results in the increased flow of cardioplegic solution and the decreased ischemic injury of myocardium during ischemic arrest and the improved recovery of myocardial function after reperfusion, and a dose-response relation must be established before clinical use.

• Journal of Chest Surgery
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• v.25 no.4
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• pp.429-434
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• 1992

We experienced a rare case of traumatic ventricular septal defect by penetrating stab injury The patient was 26-year-old women who got stab wound at the left anterior third intercostal space and left sternal border with a knife. seven hours after admission, the patient was undertaken an emergency thoracotomy due to hypovolemic shock caused by massive bleeding from transected left internal mammary artery, vein, and right ventricular outflow tract. On postoperative second day, the patient was suffered from moderate dyspnea, and arterial blood gas analysis and chest X-ray revealed hypoxemia and pulmonary edema. Right heart cardiac catheterization with Swan-Ganz Cathater showed oxygen step-up between right atrium and main pulmonary artery and a 1.6:1 ratio of pulmonary to systemic blood flow. At operation, harsh systolic thrill was palpable along right ventricular outflow tract. Through small vertical right ventriculotomy, the linear ventricular septal laceration on infundibular septum was noticed, and its size was 1.5cm with sharp margin This defeat was repaired by three interrupted matress sutures using Prolene 4-O with pledget. Her postoperative course was uneventful, and she discharged with good physical condition.

• Journal of Chest Surgery
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• v.18 no.2
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• pp.151-156
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• 1985

A clinical analysis was done on 50 cases of ventricular septal defect, operated from April 1981 to March 1984 at the department of Thoracic and Cardiovascular Surgery, School of Medicine, Keimyung University. Among 50 cases, 34 cases were males and 16 cases were females. Their age ranged from 1 to 26 years and the mean age was 9.7 years. The main symptoms at admission were frequent upper respiratory infection [50%], exertional dyspnea [42%] and palpitation [34%]. In anatomical classification by Kirklin, type I constituted 20%, type II 76%, type IV 4%. Associated congenital cardiac lesions were pulmonic stenosis [6 cases], patent foramen ovale [5 cases], aortic insufficiency [3 cases] and persistent left superior vena cava [1 case]. When a normal electrocardiogram pattern was present, Qp/Qs, Rp/Rs and pulmonary artery systolic pressure and Pp/Ps were relatively low. Among cases of above 1 cm2/M2 BSA in size of defect, Pp/Ps and pulmonary artery systolic pressure were increased than the cases of below 1 cm2/M2 BSA [P=0.01]. The postoperative right bundle branch block was occurred in 21 cases [75%] among 28 cases of right ventriculotomy approach. The operative mortality was 2% [1 case] among 50 cases and complication rate was 14% [7 cases].