• Childhood Kidney Diseases
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• v.11 no.1
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• pp.74-82
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• 2007

Purpose : To analyze the clinical characteristics, spontaneous resolution rate and predictive factors of resolution in children with primary vesicoureteral reflux(VUR). Methods : Between October 1991 and July 2003, 149 children diagnosed with primary VUR at Chonbuk National University Hospital were reviewed retrospectively. All of the patients were maintained on low-dose antibiotic prophylaxis and underwent radionuclide cystograms at 1 year intervals over 3 years after the initial diagnosis of VUR by voiding cystourethrogram was made. Results : The median time to resolution of VUR was 24 months and the total 3 year-cumulative resolution rate of VUR was 61.7%. The following variables were associated with resolution of VUR according to univariate analysis-; age<1 year, male gender, mild grade of reflux, unilateral reflux, congenital hydronephrosis as clinical presentation at time of diagnosis of VUR, absence of focal defects in the renal scan at diagnosis, absence of recurrent UTI, renal scars and small kidney during follow-up. After adjustment by Cox regression model, five variables remained as independent predictors of VUR resolution; age<1 yew, relative risk 1.77(P<0.05), VUR grade I+II 2.98(P<0.05), absence of renal scars 2.23(P<0.05), and absence of small kidney 5.20(P<0.01) during follow-up. Conclusion : In this study, spontaneous resolution rate of VUR, even high grade reflux, is high in infants during medical management, and it was related to age, reflux grade at diagnosis, absence of renal scars and small kidney during follow-up. Therefore early surgical intervention should be avoided and reserved for the selected groups.

• Investigative Magnetic Resonance Imaging
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• v.4 no.2
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• pp.85-93
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• 2000

Purpose: To evaluate the availability of magnetic resonance (MRI voiding cystography for the diagnosis of vesicoureteral reflux (VUR) and to compare the sensitivity of MR voiding cystography (MRVC) with that of radiographic voiding cystourethrography (VCUG) in the detection of VUR. Material and Methods : MRVC was performed upon 20 children referred for investigation of VUR. Either coronal T1-weighted spin-echo or spoiled gradient-echo images were obtained before and after transurethral administration of a mixture of normal saline and gadopentetate dimeglumine, and immediately after voiding. The findings of MRVC were compared with those of VCUG performed within 6 months of MRVC. Results 1 VUR was detected in 23 ureterorenal units f16 VUR's by both methods, five VUR's by VCUG, and two VUR's by MRVC). The sensitivity of VCUG and MRVC in detecting VUR was 91.3% (21/23) and 78.3% (18/23), respectively. MRVC detected renal scarring in 15 out of 17 kidneys with scintigraphically detected renal scarring. Conclusion : Although MRVC is slightly less sensitive than VCUG in the detection of VUR, it can be used for the diagnosis of VUR and renal scarring simultaneouslyl and thus will reduce the radiation hazard.

• The Korean Journal of Physiology
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• v.18 no.2
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• pp.163-169
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• 1984

The effect of vanadate on the optimum pH of Na-K-ATPase was investigated. The results were as follows: 1) The optimum PH of Na-K-ATPase was shifted from PH 7.4 to 6.8 at 10 mM K by $5{\times}10^{-6}M$ vanadate. 2) The ratio of Na-K-ATPase activity at pH 6.8 and 7.4 increased with increasing vanadate concentration. 3) Inspite of the presence of $5{\times}10^{-6}M$ vanadate Na-K-ATPase activity at pH 7.4 was higher than that at pH 6.8 below 50 mM $Na^+$, and the ratio of Na-K-ATPase activity at pH 7,4 and 6.8 was higher than that of the control. 4) Na-K-ATPase activity at pH 7.4 was higher than that at pH 6.8 below 7mM $K^+$. 5) Optimum pH of Na-K-ATPase activity was shifted from pH 7.4 to 6.8 by $10^{-5}M$ vanadate at 5 mM $K^+$. 6) $K^+$-pNPPase activity increased with lowering of pH, and the degree of inhibition of $K^+$-pNPPase activity by $10^{-7}$M vanadate was decreased with lowering of pH. These results suggest that vanadate shifts the optimum pH of Na-K-ATPase activity to more acidic PH than PH 7.4. This effect may not be caused by the decrease in the inhibitory potency of vanadate itself to Na-K-ATPase by the change of medium pH, but mainly by the alteration of Na-and K-binding site, which appears in the presence of vanadate only.

• Childhood Kidney Diseases
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• v.7 no.1
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• pp.44-51
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• 2003

Purpose : Acute pyelonephritis in children may result in permanant renal damage which later in life may lead to hypertension and renal failure. The purpose of this study was to evaluate the factors that might be useful for predicting the development of renal scar in children with urinary tract infection(UTI). Methods : We retrospectively reviewed 442 patients with UTI who were admitted to the Department of Pediatrics of Chonbuk National University Hospital, during the period from April 1992 to March 2002. The patients were divided into two groups according to the presence of renal scar on the follow-up DMSA renal scan, and we compared the factors associated with renal scarring between the two groups. Results : There were no significant differences in sex, causative organism and acute phase reactants between the groups with and without renal scar. The age at diagnosis was significantly higher in the renal scar group compared to that without scar. Of the 60 patients with renal scar, 78% had vesicoureteral reflux(VUR), but 13% of patients without scar had VUR. Furthermore, the severity of VUR was significantly correlated with renal scar formation. 53% showed multiple cortical defects on the initial DMSA renal scan, compared to 32% in the non-scar group. In addition, 76% of patients showing multiple cortical defects on the initial DMSA renal scan with VUR had renal scar. Conclusion : The presence and grade of VUR, and findings on the initial DMSA renal scan would contribute to predict risk of renal scar formation in children with UTI.

• Childhood Kidney Diseases
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• v.9 no.1
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• pp.56-63
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• 2005

Purpose : Development of renal scarring is associated with delayed diagnosis and treatment of urinary tract infection(UTI). This study was performed to clarify how soon treatment should be started to Inhibit renal scarring after onset of UTI and the factors associated with renal scarring in children with a first episode of febrile UTI. Methods : We retrospectively reviewed 163 patients with a first episode of febrile UTI under the age of 2 years from April 2000 to Ap,il 2004. All patients had a DMSA renal scan and voiding cystourethrogram done in the diagnostic period, 6 months after which a follow-up renal scan was done. After patients wet-e divided into 2 groups according to the duration of fever prior to start of treatment, the duration of fever after start of treatment, and total duration of fever, initial and follow-up DMSA scan findings were analyzed among the different groups. We compared the factors associated with renal scars between the groups with and without renal scars. Results : The initial DMSA renal scan identified abnormal finding in 23% of the patients who were treated $\leq$24 hr from the onset of disease and in 43% of those with fever more than 24 hr. Renal scars developed in 33% of patients who were treated $\leq$24 hr and 38% of those with fever >24 hr prior to treatment. Renal scars developed in 34% of patients with remission of fever $\leq$48 hr after treatment and ill 50% of those with fever >48 hr after treatment. The risk for renal scars was significantly higher in children who had total duration of feyer >72 hr(67%) than in those with shorter duration(19%). In children with renal scars, VUR was most highly associated with an increased risk of renal scar formation. Conclusion : Although children with a first episode of febrile UTI are treated within 24 hr after onset of the fever, renal damage cannot be prevented completely and it is mainly associated with VUR. (J Korean Soc Pediatr Nephrol 2005;9:56-63)

• Journal of Life Science
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• v.34 no.9
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• pp.609-619
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• 2024

Neurodegenerative diseases are marked by the accumulation of toxic misfolded proteins in neurons. Therefore, strategies for the effective prevention and clearance of aggregates are crucial for therapeutic interventions. Cytoplasmic dynein plays a crucial role in the clearance of aggregates by transporting them to the cell center, where lysosomes are enriched and the aggregates undergo extensive autophagic degradation. Previously, we reported evidence for the activation of dynein by N-acetylglucosamine kinase (NAGK) and Reln. In the present study, we explored the effects of NAGK and Reln upregulation on the clearance of aggregates. To upregulate NAGK and Reln genes in HEK293T cells (a human embryonic kidney cell line), CRISPR/dCas9 activation systems (CASs) were used with specific plasmids encoding target-specific 20 nt guide RNA. The effects of this genetic modulation were analyzed in Huntington's disease cellular models, including HEK293T cells and primary mouse cortical cells, where external mutant huntingtin (mHtt, Q74) aggregates were induced. The results showed that the CAS activation of NAGK or Reln, or their combination, significantly reduced the proportion of cells with Q74 aggregates (aggresomes). This effect was reversed by Ciliobrevin D (a dynein inhibitor) and chloroquine (an autophagy inhibitor), indicating the role of dynein-mediated autophagy in aggregate clearance. These findings provide the basis for therapeutic strategies aimed at enhancing neuronal health through targeted gene activation.