• The Korean Journal of Pharmacology
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• v.28 no.2
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• pp.137-146
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• 1992

The central tryptaminergic system has been shown to play an important role in the regulation of renal function: $5-HT_1$ receptor mediate diuresis and natriuresis, whereas both $5-HT_2$ and $5-HT_3$ mediate antidiuresis and antinatriuresis. Recently, $5-HT_1$ receptors are further subdivided into many subtypes, and central $5-HT_{1A}$ subtype was shown to mediate diuretic and natriuretic effects. The present study was undertaken to delineate the role of $5-HT_{1B}$ subtype. Trifluoromethylphenylpiperazine (TFMPP), a selective $5-HT_{1B}$ agonist in doses ranging from 8 to $750\;{\mu}g/kg$ icv elicited diuresis, natriuresis and kaliuresis in dose-dependent fashion, with the fractional excretion of filtered Na reaching 5.44% with $250\;{\mu}g/kg$ icv. The natriuresis outlasted the transient increases in renal hemodynamics, suggesting humoral mediation in the decreased tubular Na reabsorption. Plasma concentration of atrial natriuretic peptide increased along with the natriuresis. Systemic blood pressure transiently increased. When given intravenously, no diuresis and natriuresis was elicited, indicating the central mechanism. The icv TFMPP effects were not significantly affected by icv methysergide, a nonselective $5-HT_1$ blocker. Both ketanserin and MDL 72222, selective $5-HT_2$ and $5-HT_3$ antagonists, resp., did not abolish the TFMPP effects. Nor did NAN-190, $5-HT_{1A}$ blocker, affect the TFMPP effects. These observations suggest that central $5-HT_{1B}$ receptors may play a role in the central regulation of renal function by exerting diuretic and natriuretic influences, mainly through natriuretic factors.

• Childhood Kidney Diseases
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• v.1 no.1
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• pp.31-37
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• 1997

The DMSA scan is a useful radiologic study in diagnosis of morphologic and functional diseases of kidney. We evaluated the distribution of sex and age, clinical manifestations, diagnosis, combined diseases, treatment and prognosis of the 61 patients with non-functioning kidney(no isotope uptake or uptake below 5% in DMSA scan) who admitted in our hospital from 1980 to 1995. The proportion of patients under 1 year old age was 46%. Sex ratio was 1.4:1 with male predominance. Most diagnosis of non-functioning kidneys were congenital such as multicystic dysplastic kidney, hydronephrosis due to ureteropelvic junction obstruction, renal agenesis and renal hypoplasia. In order of frequency thirty one percent of them were previously detected on antenatal ultrasonogram. Treatment consisted of operation in 47.5%, mostly nephrectomy and 32.8% of patients were followed up at OPD base without definite treatment. The most common combined diseases was hydronephrosis, in 4patients who had both kidneys inveloved progressed to chronic renal failure, but the prognosis in most cases were good. It is important to evaluate renal diseases in perinatal periods, and we believe that highly sensitive diagnostic study contribute to early treatment plan and thus to good prognosis.

• Childhood Kidney Diseases
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• v.11 no.2
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• pp.239-246
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• 2007

Purpose : The progressive deterioration of renal function in children can impose a serious and lifelong impact on their lives. The ultimate goal in the management of children with chronic kidney disease(CKD) is to prolong survival, to prevent complications, and to promote growth and neurodevelopment. The aim of this study is to investigate the risk factors for the decline of renal function in pediatric CKD patients. Methods : Data from patients who met the criteria for the Kidney Disease Outcomes Quality Initiative(K/DOQI) CKD stage 2 to 4 between August 1999 and March 2007 were retrospectively analyzed. The estimated glomerular filtration rate(eGFR) was calculated by the Schwartz formula, using serum creatinine levels and height. We calculated the annual eGFR change from the difference between the baseline eGFR and the last eGFR divided by the duration(years) of the follow-up period. We analyzed the association between the annual eGFR change and factors such as age, gender, K/DOQI stage, underlying renal disease, serum calcium, and inorganic phosphorous during the follow-up period. Results : Sixty one children(44 boys & 17 girls) were enrolled. The age at entry was $7.1{\pm}4.7$ years. The annual eGFR change was $-1.2{\pm}11.9 mL/min/1.73m^2/year$. Our study showed that older age(P=0.005). hypocalcemia(P=0.012), and hypenhosphatemia(P=0.002) were significantly related to more rapid decline in renal function. Conclusion : In pediatric CKD, older age, hypocalcemia and hyperphosphatemia are related to more rapid deterioration of renal function.

• Childhood Kidney Diseases
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• v.11 no.2
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• pp.255-263
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• 2007

Purpose : A single center cross sectional retrospective study was performed to compare the outcomes of different peritoneal dialysis(PD) modalities in Korean children. Methods : Among children dialyzed with PD between the year 2004 and 2007, 35 children had reliable data on PD adequacy after 3 to 15 months of dialysis. Subjects were grouped by their modalities; 17, 13 and 5 children were on continuous ambulatory PD(CAPD), continuous cyclic PD(CCPD) and nightly intermittent PD(NIPD), respectively. Body weight and height, number of patients taking anti-hypertensives and laboratory data including biochemical and hemoglobin levels were compared. Dialysis adequacy including weekly Kt/Vurea, creatinine clearance (Ccr) and daily water removal were also compared. Patients were sub-grouped by their peritoneal permeability characteristics. Results : The percentage of patients taking anti-hypertensives, monthly change in Z-scores of body weight and height and laboratory data did not differ among the groups. Patients on CAPD and CCPD showed similar dialysis adequacies. Weekly dialytic Ccr was significantly lower in the NIPD group compared to the others. But total Ccr was not different when residual renal function was added. Weekly dialytic Ccr by CAPD was significantly higher than that of CCPD in low and low-average transporters. Conclusion : We propose that modality can be selected flexibly according to the patients' preferences. And peritoneal permeability characteristics provide valuable information for adjusting PD prescriptions in ultrafiltration failure or in inadequate dialysis. Further study of other clinical performance measures should be performed to clarify the comparable outcomes in different PD modalities.

• Childhood Kidney Diseases
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• v.18 no.2
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• pp.77-84
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• 2014

Purpose: The purpose of this study was to compare the validity of Onen's alternative grading system (AGS) with that of the APDRP and SFU grading systems in patients with isolated and complicated congenital hydronephrosis. Methods: We retrospectively reviewed the medical records of 153 patients (204 renal units) diagnosed with congenital hydronephrosis between January 2002 and December 2011. We classified patients into 2 groups; isolated or complicated hydronephrosis. All renal units were graded according to anterior-posterior diameter of renal pelvis (APDRP), Society for Fetus Urology (SFU) and Onen's grading systems. We analyzed the prognosis of hydronephrosis, according to each grading system, at 2 years of age. Results: There were 152 renal units with isolated hydronephrosis and 52 renal units with complicated hydronephrosis. The isolated hydronephrosis group had a lower grade according to Onen's AGS, and showed more frequent spontaneous remission by 2 years of age. There was more frequent obstruction (P =0.000) and surgical treatment (P =0.000) of units with high-grade hydronephrosis according to Onen's AGS. In the complicated hydronephrosis group the frequencies of spontaneous remission (P =0.015) and renal dysfunction (P =0.013) were significantly higher than those in high-grade hydronephrosis, as indicated by Onen's AGS. There were no significant differences in clinical outcomes among the highest grade groups, according to the 3 systems, in either isolated or complicated hydronephrosis. Conclusion: Onen's AGS reflects the prognosis of hydronephrosis as well as other grading systems in those with isolated hydronephrosis. It was better predictor of renal dysfunction in those with complicated hydronephrosis. However, Onen's AGS was not superior to the other grading systems in terms of predicting prognosis, especially in high-grade hydronephrosis.

• Childhood Kidney Diseases
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• v.17 no.2
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• pp.57-64
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• 2013

Purpose: In children, 24-hour urine collections are unreliable for evaluating glomerular filtration rate (GFR) because of the difficulty of regulating voiding and the daily variation of urinary creatinine up to 25%. Additionally, creatinine clearance (Ccr) based on urinary creatinine is considered inaccurate. The purpose of this study was to compare estimated GFR determined using Ccr, formulas with serum cystatin C and creatinine, and $^{99m}Tc$-mercaptoacetyltriglycine (MAG3) dynamic renal scintigraphy. Methods: This retrospective study included 101 patients (age, <18 years) who visited Chung-Ang University Hospital between July 2011 and August 2012. GFR was estimated using 24-hour urinary creatinine, five formulas with serum creatinine and cystatin C, and $^{99m}Tc$-MAG3 renal scan. Results: Of the 101 patients, glomerular renal diseases were present in 60 patients (59.4%) and non-glomerular diseases were present in 41 patients (40.6%). There was a significant correlation between estimated GFR determined using $^{99m}Tc$-MAG3 renal scan and Ccr (r=0.389, P <0.001). The correlation values between estimated GFR determined using $^{99m}Tc$-MAG3 renal scan and each formula of Schwartz, Counahan-Barratt, Cockcroft-Gault, Filler and Lepage, and Bokencamp were 0.265 (P=0.007), 0.128 (P=0.044), 0.230 (P=0.021), 0.356 (P<0.001), and 0.355 (P <0.001), respectively. $^{99m}Tc$-MAG3 renal scan was correlated with estimated-GFR by all formulas in decreased renal function. Conclusion: Estimated GFRs determined using serum creatinine and cystatin C, and $^{99m}Tc$-MAG3 renal scan correlated well with estimated GFR determined using Ccr. $^{99m}Tc$-MAG3 renal scan may be replaced for evaluation of renal function with convenience in patients with renal disease and decreased renal function in childhood.

• Journal of Veterinary Clinics
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• v.25 no.4
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• pp.257-262
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• 2008

Renal ischemia-reperfusion injury is great clinical important because viability of the transplanted organ depends on the tolerance of the graft to ischemia-reperfusion injury, an inevitable processing during surgery. The purpose of this study was to investigate the effects of irrigation-aspiration in ischemia-reperfusion injury model induced by cross-clamping of renal vessels. Blood samples were collected from these dogs for measurement of kidney function and antioxidant enzyme activity, and RI at the intrarenal artery was measured at different time intervals. And the kidneys were taken for histopathologic evaluation at day 14. Kidney function (Cr and BUN) showed a significant increasing in untreated group compared to treated group. Resistive index of intrarenal artery was no significant difference among the groups. Activity of antioxidant enzymes in plasma was significant decrease in untreated group compare to control group while in treated group was no significant difference compared to control group. In histopathologic finding, treated group was showed less damage than that of untreated group. This result suggests that the processing of irrigation-aspiration is useful to reducing ischemia-reperfusion injury.

• Proceedings of the KIEE Conference
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• 1999.11b
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• pp.122-124
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• 1999

현형 가공배전선로의 가선공법은 많은 인력이 동원되어 매전선마다 롤러에서 푸는 연선과정과 이도를 조정하는 긴선과정을 거쳐 설치된다. 따라서 이 같은 공법은 원시적이고 비효율적인 방법이므로 이를 개선하여 일시에 다선을 신설 또는 철거시공할 수 있는 공법을 개발하여 신기술로 지정받은 바 있어 이의 개요 및 작업과정과 예상효과를 소개하고자 한다.

• 대한핵의학회:학술대회논문집
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• 1991.05a
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• pp.145.2-146
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• 1991

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.193.1-193.1
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• 2012

위성시스템의 성능 및 무게, 비용 등의 요구조건이 높아지면서 시스템 설계를 위한 고성능, 고효율의 전기전자부품이 요구되고 있다. 이런 요구를 충족하기 위하여 NASA나 ESA에서 사용하고 있는 고 신뢰성과 안전성에 바탕을 둔 기존의 표준소자에 비해 신기술과 고성능으로 빠르게 업그레이드되고 있는 상용부품의 수요가 증가하고 있다. 특히 상용집적소자인 PEM은 많은 우주프로그램에서 사용되고 있고 그 영역을 넓히기 위한 연구가 계속되고 있다. 본 논문에서는 우주 프로그램에 사용하기 위한 상용 PEM소자의 고려사항과 검증동향에 대해 소개하고자 한다.