Berglund G, Greter J, Lindstedt S, Steen G, Waldenström J, Wass U
Clin Chem. 1979 Jul;25(7):1325-8.
A two-year-old boy with a malignant tumor of the brain (medulloblastoma) excreted large amounts of thymine and uracil in his urine. The excretion was related to progress and regress of the disease, and reached a maximum of 3.0 mol of thymine per mole of creatinine and 2.6 mol of uracil per mole of creatinine. The excretion by 20 apparently normal children was less than 0.01 mol/mol of creatinine for each of the two pyrimidines. Three children with brain tumors, two with leukemias, and one with neuroblastoma were also studied; two of them had a moderate increase in urinary pyrimidine excretion, but only up to 0.07 mol/mol of creatinine. The activity of dihydrouracil dehydrogenase (NADP+) (EC 1.3.1.2) in cultured fibroblasts from the patient was somewhat lower than in control fibroblasts. The tumor was considered to be the likely cause of the increased excretion of pyrimidines, but an impaired degradation of pyrimidines in the liver could not be ruled out.
一名患有脑恶性肿瘤（髓母细胞瘤）的两岁男孩尿液中排出大量胸腺嘧啶和尿嘧啶。这种排泄与疾病的进展和消退有关，每摩尔肌酐中胸腺嘧啶的排泄量最高达到3.0摩尔，每摩尔肌酐中尿嘧啶的排泄量最高达到2.6摩尔。20名明显正常儿童的这两种嘧啶的排泄量均低于每摩尔肌酐0.01摩尔。还对三名患有脑肿瘤、两名患有白血病和一名患有神经母细胞瘤的儿童进行了研究；其中两名儿童的尿嘧啶排泄量有适度增加，但最高仅达到每摩尔肌酐0.07摩尔。患者培养的成纤维细胞中二氢尿嘧啶脱氢酶（NADP +）（EC 1.3.1.2）的活性略低于对照成纤维细胞。肿瘤被认为是嘧啶排泄增加的可能原因，但不能排除肝脏中嘧啶降解受损的可能性。
