Biomedical subjects

Young Seo Park

Publications and source records attributed to Young Seo Park.

7 recordsLinked to original sources

PubMed2006

Vesicoureteral reflux increases the risk of renal scars: a study of unilateral reflux.

The aim of this study was to assess the impact of vesicoureteral reflux (VUR) on renal scar following acute pyelonephritis by comparing the refluxing renal units with nonrefluxing renal units in children with unilateral primary VUR. Forty-eight children with unilateral primary VUR diagnosed after the first pyelonephritis were enrolled. Mean age of patients was 1.0+/-1.6 years (29 boys and 19 girls). All patients underwent renal ultrasonography and renal 99 m-technetium dimercaptosuccinic acid (DMSA) scan within three days following the diagnosis of pyelonephritis, and voiding cystourethrography (VCU) was performed soon after fever subsided and the infection was controlled. The DMSA scan was rechecked six months after the initial study when the first scan showed a renal defect. The first DMSA showed renal defects in 34 (70.8%) out of 48 of the refluxing renal units and in 13 (27.1%) out of 48 of the nonrefluxing renal units (P<0.01, OR: 6.54). At six months after the infection, 23 (47.9%) out of 48 refluxing renal units and seven (14.6%) out of 48 nonrefluxing renal units had renal scars on DMSA scan (P<0.01, OR: 5.39). The prevalence of renal scars did not vary significantly according to the grade of VUR. The CRP level on admission was significantly higher in patients with acute renal defect and scar. In conclusion, VUR increases the risk of post-pyelonephritic renal scars in children.

Child, Preschool↗

PubMed2006

Arbitrary-ratio image resizing using fast DCT of composite length for DCT-based transcoder.

We propose a fast arbitrary-ratio image resizing method for transcoding of the compressed images. The downsizing process in the discrete cosine transform (DCT) domain can be implemented by truncating high-frequency coefficients, whereas the upsizing process is implemented in the DCT domain by padding zero coefficients to the high-frequency part. The proposed method combines a fast inverse and forward DCT of composite length for arbitrary-ratio upsizing or downsizing. According to the resizing ratio, truncating the high-frequency coefficients and padding zeros are appropriately considered by combining the inverse DCT and forward DCT. The proposed method shows a good peak signal-to-noise ratio and less computational complexity compared with the spatial-domain and previous DCT-domain image resizing methods.

Algorithms↗

PubMed2006

Two cases of isolated diffuse mesangial sclerosis with WT1 mutations.

Here we report two cases of isolated diffuse mesangial sclerosis (IDMS) with early onset end-stage renal failure. These female patients did not show abnormalities of the gonads or external genitalia. Direct sequencing of WT1 PCR products from genomic DNA identified WT1 mutations in exons 8 (366 Arg>His) and 9 (396 Asp>Tyr). These mutations have been reported previously in association with Denys-Drash syndrome (DDS) with early onset renal failure. Therefore we suggest that, at least in part, IDMS is a variant of DDS and that investigations for the WT1 mutations should be performed in IDMS patients. In cases with identified WT1 mutations, the same attention to tumor development should be required as in DDS patients, and karyotyping and serial abdominal ultrasonograms to evaluate the gonads and kidney are warranted.

Base Sequence↗

PubMed2005

A case of atypical hemolytic uremic syndrome with a transient decrease in complement factor H.

We report a case of sporadic atypical hemolytic uremic syndrome (HUS) with a transient decrease in complement factor H. Referred for hemolysis and azotemia without diarrhea prodrome, this 31-month-old boy showed a decreased complement 3 (C3) and complement factor H (FH) level. However, the factor H gene (HF1) mutation was missing. After the hemolysis was controlled with plasma infusion, the C3 and FH levels recovered. The patient's renal function fully recovered and remained normal, and there was no recurrence of the HUS.

Child, Preschool↗

PubMed2004

Age-related differences in adriamycin-induced nephropathy.

We investigated the effects of age on adriamycin-induced nephropathy in mice. Disease was produced by a single intravenous injection of adriamycin (doxorubicin hydrochloride) (AD, 20 mg/kg) in female Balb/C mice of 5 and 12 weeks of age. Urinary protein and transforming growth factor (TGF)-beta1 concentrations were measured and the extent of glomerular sclerosis/hyalinosis and tubulointerstitial fibrosis was scored. Decorin and fibromodulin expression was quantified using reverse transcription-polymerase chain reaction. In normal mouse kidneys, urinary TGF-beta1 excretion and decorin and fibromodulin mRNA did not change with age. When nephropathy was induced, the 12-week-old group demonstrated significantly greater proteinuria, urinary TGF-beta1 excretion, and interstitial fibrosis ( P<0.05) than the 5-week-old group. Decorin and fibromodulin expression was not significantly different between the groups. We conclude that 12-week-old mice develop more severe nephropathy than the younger mice following administration of the equivalent weight-based dose of AD. Decorin and fibromodulin do not play a role in this difference.

Age Factors↗

PubMed2003

Acute pancreatitis associated with biliary disease in children.

BACKGROUND AND AIMS: Biliary disease is one of the most common causes of acute pancreatitis in adults; however, this cause and outcome in children have rarely been described in the literature. Therefore, the present study was conducted to evaluate the role of biliary disease as a cause of acute pancreatitis in children. METHODS: The present study included 56 children with acute pancreatitis, of which 16 (29%) cases were associated with biliary disease. The 16 cases consisted of four boys and 12 girls ranging in age from 2 to 13 years. The underlying causes of the biliary disease were evaluated, as well as its clinical presentations, management modalities, and outcomes. RESULTS: The causes of biliary disease in the 16 children included choledochal cyst in seven, biliary sludge in six, gallstone in two, and anomalous pancreaticobiliary junction in one. Acute pancreatitis with biliary disease showed increased presentation of jaundice and abnormalities in a liver-function test. Therapeutic interventions were performed more frequently in acute pancreatitis associated with biliary disease. All seven children with choledochal cysts needed hepaticojejunostomy. Of eight children with biliary sludge or gallstones, five children remained free of and two suffered from repeated attacks of pancreatitis after endoscopic papillotomy. Mortality did not occur. CONCLUSION: The present study suggests that biliary disease can be one of the causes of acute pancreatitis in children and has the clinical characteristics of jaundice and/or abnormalities in a liver-function test. Appropriate therapeutic interventions should be considered as the treatment modality.

Acute Disease↗

PubMed2003

Value of supranormal function and renogram patterns on 99mTc-mercaptoacetyltriglycine scintigraphy in relation to the extent of hydronephrosis for predicting ureteropelvic junction obstruction in the newborn.

UNLABELLED: We investigated the value of supranormal function and renogram patterns on (99m)Tc-mercaptoacetyltriglycine ((99m)Tc-MAG3) scintigraphy in relation to the extent of hydronephrosis for predicting ureteropelvic junction (UPJ) obstruction in the newborn. METHODS: We studied 48 patients with prenatally diagnosed unilateral hydronephrosis that was confirmed on postnatal ultrasonography. The anteroposterior pelvic diameter (APPD) and the Society for Fetal Urology (SFU) grade were measured on 1-mo ultrasonography to assess the extent of hydronephrosis. Neonates with an APPD of or=55%) and renogram grades (1, not obstructive; 2, indeterminate; 3, obstructive; and 4, prolonged parenchymal transit) were determined on 1-mo (99m)Tc-MAG3 renography. Multivariate logistic regression analysis was performed to predict the presence of obstruction. RESULTS: Of the 48 kidneys with hydronephrosis, 19 were diagnosed as having UPJ obstruction. Twenty-nine kidneys were classified as having nonobstructive hydronephrosis. The APPD of the 19 kidneys with obstruction (24.3 +/- 9.2 mm) was significantly larger than that of the 29 kidneys without obstruction (17.5 +/- 11.2 mm; P < 0.05). The SFU grades of UPJ obstruction (2 with grade 3, 17 with grade 4) were also significantly higher than those without UPJ obstruction (grades 1-4 in 1, 6, 10, and 12 kidneys, respectively; P < 0.01). Supranormal function was present in 4 kidneys with UPJ obstruction but in none without obstruction (P < 0.001). (99m)Tc-MAG3 renography of the 19 obstructions showed grades 2, 3, and 4 renograms in 4, 8, and 7 patients, respectively. The 29 without obstruction revealed significantly lower grades (grades 1-4 in 10, 13, 5, and 1 patient, respectively; P < 0.001). Multivariate logistic regression analysis revealed that the addition of supranormal function or renogram grade in the model significantly increased the likelihood ratio in comparison with that of the SFU grade only (chi(2) = 7.73 and 9.99, respectively; P < 0.01). Of the 29 neonates with SFU grade 4, supranormal function or renogram >or= grade 4 had a positive predictive value of 90% (9/10). CONCLUSION: (99m)Tc-MAG3 renography at 1 mo after birth has a significant additive value in relation to the degree of hydronephrosis in predicting UPJ obstruction in patients with prenatally diagnosed unilateral hydronephrosis with normal function.

False Positive Reactions↗