• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.67-73
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• 2016

Recently, wireless power transmission has attracted much interest and is the subject of much research in industry and academia. As its name implies, it is a technology which involves transferring power without wires. This paper presents the design of an ICT-based wireless power transmission system. The proposed system consists of a wireless transceiver unit and high-efficiency coil unit, which can increase both the transmission efficiency and the effective power distance. In particular, the wireless transceiver unit was designed to work with the ICT technique to enable real-time remote monitoring. Also, studies were done relating to the effect of reducing the standby power. The optimal frequency of IGBT devices used in industrial wireless power systems of 20[KHz] was utilized. The values of $23.9[{\mu}H]$ and $2.64[{\mu}F]$ were selected for L and C, respectively, through many field experiments designed to optimize the system design. In addition, an output current controlling algorithm was developed for the purpose of reducing the standby power. The results presented in this paper represent a 75[%] to 85[%] higher power transmission efficiency with a 10[%] increase in the effective power transmission distance compared with the existing systems. As a result, the proposed system exhibits a lower standby power and maintenance costs. Also, the designed wireless transceiver unit facilitates fault detection by means of user acquired data with the development of the ICT applied program.

• Journal of Chest Surgery
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• v.34 no.10
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• pp.769-774
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• 2001

Background: Descending necrotizing mediastinitis(DNM) is a serious complication originating in odontogenic or oropharyngeal infection with previously reported mortality rates of 25% to 40%. We retrospectively reviewed the 4 years of our surgical drainage and debridement in DNM. Material and Method: We studied 7 cases diagnosed as DNM from 1997 through 2000. Primary oropharyngeal infection lead to DNM in four cases(57%) and odontogenic abscess in three cases(43%). All patients were received emergent cervicotomy and thoracotomy or sternotomy for debridement of necrotic tissue and mediastinal or pleural drainage. Result: Five cases were evolved well and were discharged after a mean of 42 days. Two patients(28.6%) died. Three patients required reoperation due to local surgical complication; empyema(two) and impending cardiac tamponade. One of these patients died on 12 post-reoperative day due to great vessel erosion, renal and respiratory insufficiency. The other patient died of broncho- esophageal fistula and asphyxia on 10 postoperative day without reoperation. Conclusion: On the basis of experience accrued in treating these patients, early diagnosis by cervicothoracic computed tomographic scan of neck and thorax aids in rapid indication of a surgical approach of DNM. We emphasize that performing early surgical drainage and debridement of necrotic tissues with intensive postoperative care can significantly reduce the mortality rate.

• Journal of Chest Surgery
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• v.30 no.6
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• pp.585-590
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• 1997

Between December 1994 and October 1996, 57 premature infants with evidence of a hemodynamically significant PDA associated with cardiopulmonary compromise underwent indomethcin therapy(Group I, n=48) or surgical ligation(Group II, n=9) because of indomethacin failure. The gestational alee(29.6$\pm$ 3.1weeks vs. 28.1 $\pm$ 1.6weeks) and birth weight(1,413 $\pm$ 580gm, ,098 $\pm$ 235gm) showed no significant differences between the two groups. Medical management included fluid restriction, diuretics, and indomethacin therapy(one or two cycles). Surgical libation was done at the neonatal intensive care unit(NICU) without moving the patient to the operation room. There was no complication associated with the operation. There were 9 deaths in Group I(19%, 9/48) and 2 deaths in Group II(22% , 219). The main causes of deaths were persistent bronchopulmonary dysplasia with sepsis(n=8) and intrapulmonary hemorrhage(n=3). The rate of medical treatment failure including death and complication in premature infants whose body weights were less than 1500gm was higher(41%, 15/38) than in premature infants whose body weights were more than 1500gm(16%, 3/19). Early surgical ligation of PDA may be applicable in the premature infant with a large size, low birth weight(<1500 gm), or associated intracardiac anomalies. Perfoming the operation in the NICU may be safe in s ead of moving the patient to the operating room.

• Journal of Veterinary Clinics
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• v.24 no.3
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• pp.392-399
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• 2007

Scutellaria baicalensis Georgi. (SBGE) is known to be antioxidant effect. In addition of the effects, we further investigated the SBGE on the antioxidant effect on a renal cortical slices cell and kidney protecting effects. The results were as follows. 1 When renal cortical slices separated from a rabbit's kidney were treated with 1mM tert-Butylhydroperoxide (t-BHP) in the presence of SBGE. SBGE significant prevented t-BHP induced increase in lactate dehydrogenase (LDH) release and lipid peroxidation. 2. When renal cortical slices separated from a rabbit's kidney were treated with oxidant $300{\mu}M$ cisplatin in the presence of SBGE. SBGE significant prevented cisplatin-induced increase in LDH release and lipid peroxidation. 3. Pretreatment with 0.1g/kg SBGE for seven day and treatment with 5 mg/kg cisplatin by the intraperitoneal injection The results were that the pretreatment group with SBGE showed a significant decrease in lipid peroxidation, increase in clearance rate of blood urea nitrogen (BUN) and creatinine in the kidney than the administering single agent group of cisplatin. and pretreatment group with SBGE showed intact microvillus of proximal tubule and no contraction of rumen, it was a similar result with normal group. With the results SBGE showed to be highly effective on antioxidant effect and cellular protection activity against cisplatin that was a toxic agent on a kidney. Therefore, SBGE is considered to have protective effective on a disordered kidney or kidney diseases such as nephritis or renal failure that cause tissue damages in a kidney.

• Journal of Preventive Medicine and Public Health
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• v.39 no.2
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• pp.149-158
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• 2006

Objectives : We wanted to evaluate the economic value of a pharmaceutical product, Kremezin, for treating patients with chronic renal failure (CRF) by estimating the amount of cost savings due to its effect for delaying the initiation of dialysis treatments. Methods : We defined a conventional treatment for CRF accompanied by Kremezin therapy as 'the treatment group' and only conventional treatment as 'the alternative group.' The types of costs included were direct medical and nonmedical costs and costs of productivity loss. The information on the effect of Kremezin was obtained from the results of earlier clinical studies. Cost information was derived from the administrative data for 20 hemodialysis and 20 peritoneal dialysis patients from one tertiary care hospital, and also from the administrative data of 10 hemodialysis patients from one free-standing dialysis center. Per-capita cost savings resulting from Kremezin therapy were separately estimated for the cases with delay for the onset of hemodialysis and the cases with immediate performance of peritoneal dialysis. By computing the weighted average for the cases of hemodialysis and peritoneal dialysis, the expected per-capita cost savings of a patient with CRF was obtained. Using a discount rate of 5%, future cost savings were converted to the present value. Results : The present value of cumulative cost savings per patient with CRF from the societal perspective would be $18,555,000{\sim}29,410,000$ Won or $72,104,000{\sim}112,523,000$ Won if Kremezin delays the initiation of dialysis by 1 or 4 years. Conclusions : The estimated amount of cost savings resulting from treating CRF patients with Kremezin confirms that its effect for delaying the onset of dialysis treatments has a considerable economic value.

• Childhood Kidney Diseases
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• v.7 no.2
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• pp.204-210
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• 2003

Membranoproliferative glomerulonephritis type II(MPGN II), also called dense deposit disease, was first described by Berger and Galle in 1963. The diagnosis of MPGN II is based on electron-microscopic finding of an intensely electron-dense substance which replaces the lamina densa of the glomerular basement membrane. Although the etiology and pathogenesis of MPGN II are unknown, it frequently progresses to end-stage renal failure. Typically in MPGN II, hypocomplementemia due to activation of the alternative complement pathway is present. In addition, the association of MPGN II with partial lipodystrophy and complement abnormalities is well documented. The relationship between these associated features and the patient's renal functional outcome is not clear. With respect to the therapy for MPGN II, an alternate-day prednisolone regimen was shown to be effective. Various treatment modalities, including immunosuppression with corticosteroids, cytotoxic drugs and cyclosporin A, anticoagulants and antiplatelet therapies are used, either alone or in combination, with varying degrees of success. The purpose of this paper is to present a case of MPGN II from a 7 years old girl with paroxysmal supraventricular tachycardia(PSVT).

• Childhood Kidney Diseases
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• v.14 no.1
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• pp.32-41
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• 2010

Purpose : Glomerulonephropathy (GN) often manifests as proteinuria and progresses to chronic renal failure without specific therapy. Mesenchymal stem cell (MSC) has been tried as a therapeutic agent in experimental GN, and previous studies showed that administration of MSC concomitantly to the insult inducing GN or via intra-renal administration ameliorated proteinuria. The purpose of this study was to test the therapeutic potential of MSC administered via intravenous route at the time of clinically evident proteinuria. Methods : MSCs were administered intravenously via tail vain into the mice with adriamycin (ADR) induced nephropathy (ADR-GN), two weeks after ADR injection when massive proteinuria was evident. To test the capacity of MSC modulate the cytokine production in the inflammatory milieu, the concentrations of IFN-$\gamma$ and IL-10 were measured in the supernatant of in vitro mixed lymphocyte culture (MLC) with or without additional MSC. Results : MSCs administered intravenously into the proteinuric mice with ADR-GN accelerated the recovery of this experimental GN with disappearance of proteinuria in two weeks when the saline treated (control) mice still showed significant proteinuria. The mice treated with MSC also had a tendency of better survival. Addition of MSC decreased IFN-$\gamma$ and increased IL-10 in the supernatant of MLC. Conclusion : This study showed that MSC had a therapeutic potential even when administered in a more clinically relevant setting into a proteinuric glomerulonephropathy model. Further study to verify the mechanism and long-term safety of this phenomenon is required.

• The Korean Journal of Nuclear Medicine
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• v.16 no.1
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• pp.7-14
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• 1982

In an attempt to evaluate the various serum hormonal changes in terminal renal failure, the fasting $T_4,\;T_3,\;rT_3$, gastrin, secretin prolactin, and aldosterone were measured by radioimmunoassay in 12 patients with chronic renal failure, who were admitted to Chosun University Hospital from January to June, 1981. From the analysis the following results were obtained. 1. Mean values of serum hormonal concentration in 10 normal control were as follows: $T_4,\;12.93{\pm}2.00ug/ml$; $T_3,\;113.0{\pm}28.7ng/ml$; $rT_3,\;0.11{\pm}0.10ng/ml$; gastrin, $100.0{\pm}47.1pg/ml$; secretin, $32.46{\pm}11.45pg/ml$; prolactin, $11.0{\pm}3.6ng/ml$; aldosterone, $137.0{\pm}58.5pg/ml$, 2. Mean values of serum hormonal concentration in 12 chronic renal failure were as follows: $T_4,\;7.34{\pm}2.43ug/ml$; $T_3,\;71.0{\pm}19.1ng/ml$; reverse $T_3,\;0.38{\pm}0.19ng/ml$; gastrin, $162.5{\pm}40.2pg/ml$; secretin, $107.50{\pm}20.48pg/ml$; prolactin, $34.0{\pm}17.2ng/ml$; Aldosterone, $86.5{\pm}19.8pg/ml$. 3. In chronic renal failure group, serum T 4, T 3 and adosterone level were significantly lower than those of the control group, but serum $rT_3$, gastrin, secretin and prolactin were significantly higher than those of the control group. 4. In the view of the correlation between serum hormonal concentions and serum creatinine levels in patients with chronic renal failure, $rT_3$, gastrin, secretin and prolactin showed increasing tendency(positive correlations), whereas $T_4,\;T_3$ and aldosterone showed decreasing tendency (negative correlations) with increment of serum cteatinine levels. And so, we observed the negative correlation between $T_3\;and\;rT_3$.

• Journal of the Korean Society for Nondestructive Testing
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• v.27 no.4
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• pp.299-304
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• 2007

There are to be some cracks on the material degradation part or the stress concentration parts of the main members, which carry on over-loads, of structures. Because these cracks can be used to evaluate the structural health status, it is important to monitor the crack growth for maintaining the structural safety. In this study, the fiber Bragg grating sensor with a drop ball was developed as a sensor for crack growth detection of an existing crack. The crack growth detection sensor was constructed with three parts: a probe part, a wavelength controling light source and receiver part, and an impact part. The probe part was just formed with a fiber Bragg grating optical fiber The wavelength controling light source part was composed of a current supplying circuit, a DFB laser diode, and a TEC controling circuit for wavelength control. Also, the impact part was just implemented by dropping a steel ball. The performance of this sensor was confirmed by the experiments of the crack detection with an aluminum plate having one existing crack. According to these experiments, the difference of the sensor signal outputs was correlated with the crack length. So, it was confirmed that this sensor could be applied to monitor the crack growth.

• Annals of Clinical Neurophysiology
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• v.3 no.2
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• pp.136-142
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• 2001

Background : Nervous system dysfunction is a major complication of end stage renal disease. Although severe neurologic symptoms are partially or completely reversed by adequate hemodialysis, even optimally dialyzed patients will usually not return to normal neurocognitive function. To investigate the influence of chronic renal failure and hemodialysis on higher cognitive function electrophysiologically, we studied auditory P300 event-related potentials in 14 hemodialysis patients and 14 age- and sex-matched normal healthy controls. Methods : The subjects consisted of 14 patients(M: 6, F: 8) with chronic renal failure(CRF) for 1 to 10 years and 14 age- and sex-matched healthy controls(M: 5, F: 9). For the reliability of study, patients with diabetes mellitus, abnormal brain CT findings, or low mini-mental state score(below 20) were excluded. Event related potentials(ERPs) for hemodialysis patients were performed at pre- and post-hemodialysis. To obtain ERPs, subjects underwent 2-tone auditory discrimination test(oddball paradigm). Results : Although the age(control: $48.79{\pm}10.31years$, CRF: $51.21{\pm}7.61years$) and mini-mental state score(control: $27.00{\pm}1.71points$, predialysis CRF: $25.07{\pm}3.58points$) were not different in normal control and CRF groups significantly(P>0.05), P300 latencies at Cz(control: $288.11{\pm}17.36msec$, predialysis CRF: $332.35{\pm}42.34msec$) were significantly delayed(P<0.05)and the duration of Trail making test A was significantly prolonged(control: $64.2{\pm}24.2sec$, CRF: $118.9{\pm}101sec$) in CRF group. P300 latencies between pre- and post-hemodialysis CRF patients(predialysis CRF: $332.35{\pm}42.34msec$, postdialysis CRF: $325.82{\pm}38.69msec$) were not significantly different. The P300 latency was not related with the duration of CRF(Spearman's correlation test, r=0.25, P>0.05) and the frequency of hemodialysis(Spearman's correlation test, r=0.28, P>0.05). Conclusions : From these results, we suggest that P300 latency is valuable in evaluating cognitive brain dysfunction in patients with CRF and hemodialysis does not have a significant effect on cognitive brain dysfunction in patients with CRF.