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Yum-Kung Chu

Publications and source records attributed to Yum-Kung Chu.

6 recordsLinked to original sources

PET imaging of brain astrocytoma with 1-11C-acetate.

PURPOSE: The purpose of this study was to assess the use of 1-(11)C-acetate (ACE) as a metabolic tracer for the detection and characterisation of astrocytomas. METHODS: Positron emission tomography (PET) studies with ACE and 2-(18)F-fluoro-2-deoxy-D-glucose (FDG) were performed sequentially in 26 patients with primary astrocytomas. Images were analysed by visual interpretation and determination of the tumour to cortex ratio (T/C ratio) and standardised uptake value (SUV). The tumour uptake was visually scored into three grades as compared with the contralateral cortex: clearly lower (-), almost equal (+) and clearly higher (++). RESULTS: There were 85% of astrocytomas with ++ ACE uptake, 15% with + ACE uptake and none with - ACE uptake. Only 19% of astrocytomas had ++ FDG uptake. Thirty-seven percent of high-grade astrocytomas had + FDG uptake and 37% had - FDG uptake. The sensitivity and specificity of the FDG T/C ratio in discriminating high-grade from low-grade astrocytomas were 79% and 100%, respectively, at the cutoff value of 0.75. Using 2.33 as the cutoff value of the ACE T/C ratio, the sensitivity and specificity were 42% and 86%, respectively. FDG was better than ACE in discriminating high-grade from low-grade astrocytomas. T/C ratios and SUVs of FDG uptake of tumours correlated with the histological grades, but those of ACE uptake did not. CONCLUSION: ACE appears to be a promising tracer for use in the detection of primary astrocytomas, but is of limited value in the differentiation of high- and low-grade astrocytomas. ACE is complementary to FDG for the diagnosis and characterisation of astrocytoma.

Acetates↗

Xanthogranulomatous pyelonephritis treated by partial nephrectomy.

Xanthogranulomatous pyelonephritis is an uncommon disease in children. We report of a 2-month-old girl with urinary tract infection and with a renal mass detected by ultrasound scan. The preoperative differential diagnoses were Wilms tumor, multicystic dysplastic kidney, renal abscess, and mesoplastic nephroma. The subsequent histopathological findings allowed the diagnosis of xanthogranulomatous pyelonephritis (XGP). Although XGP is rare at this age, it must be considered in the differential diagnosis of a child presenting with renal mass, either with or without associated urolithiasis, anemia, and elevated inflammatory markers. The long-standing mainstay of therapy for diffuse XGP has been nephrectomy. However, we report the successful preservation of renal mass with partial nephrectomy for diffuse XGP. The affected kidney grew normally and preserved residual function after the operation. Hence we strongly suggest parenchymal saving in pediatric cases of XGP to preserve renal function.

Antihypertensive Agents↗

High prevalence of a novel mutation (2268 insT) of the thyroid peroxidase gene in Taiwanese patients with total iodide organification defect, and evidence for a founder effect.

The mutation of the thyroid peroxidase (TPO) gene that causes the total iodide organification defect (TIOD) is a common and severe condition leading to dyshormonogenesis of the thyroid gland in Caucasians. However, the role of TIOD in Chinese patients with thyroid dyshormonogenesis is unknown. In this study we followed 16 patients from 16 unrelated families in Taiwan and performed perchlorate discharge examination. Seven patients had TIOD and 2 had the partial iodine organification defect (PIOD) among the 16 families. These 9 patients underwent screening in search of TPO gene mutations. Three new mutations (2268 insT, 2243 delT, and G157C) were detected in the 7 patients with TIOD, whereas no mutation in the TPO gene was found in the 2 patients with PIOD. The 2268 insT mutation was noted to be the most common among these TIOD patients (12 of 14 studied alleles, 86%). With 3 intragenic polymorphic markers, we found that the alleles carrying the 2268 insT mutation in Taiwan Chinese TIOD patients were tightly linked to a specific haplotype. The allele frequencies of this haplotype in the 8 patients with homozygous 2268 insT (5 unrelated families, 10 studied alleles) and in 49 normal individuals (98 studied alleles) were 1.00 and 0.02, respectively (P < 0.0001). This indicates that this common novel mutation among Taiwanese patients with TIOD is due to a founder effect.

Asian People↗