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Norikazu Shimizu

Publications and source records attributed to Norikazu Shimizu.

10 recordsLinked to original sources
PubMed2006

[Case of Sanfilippo syndrome type B and Wilson disease born to unrelated parents].

A 5-year-old boy visited a hospital because of macrocephalus, mental retardation and hepatic dysfunction, and was suspected to have Wilson's disease since his father had this disease. The serum level of ceruloplasmin was low, but urinary copper excretion was not increased markedly. He was treated with D-penicillamine. He was then reffered to our hospital because of his facial features suggesting mucopolysaccharidosis. Based on mucopolysacchariduria and the deficiency of N-acetylglucosaminidase, the diagnosis of Sanfilippo syndrome type B was made. Molecular analyses identified him as a compound heterozygote for both the ATP7B (A844V/2659delG) and alpha-N-acetylglucosaminidase (V241M/R482W) genes, responsible for Wilson's disease and Sanfilippo syndrome type B, respectively. Although born to non-consanguineous parents, he had two rare autosomal recessive diseases. In this case, liver dysfunction was attributed to Wilson's disease, and mental retardation to Sanfilippo syndrome.

Acetylglucosaminidase↗
PubMed2005

Identification of three novel mutations in Japanese patients with Menkes disease and mutation screening by denaturing high performance liquid chromatography.

BACKGROUND: Menkes disease is an X-linked recessive disorder resulting in a connective-tissue disturbance and profound neurodegeneration in early childhood. The gene for Menkes disease has been isolated and predicted to code for copper transporting ATPase. In this study, a mutation analysis in Japanese patients with Menkes disease was performed, as was a mutation screening by denaturing high performance liquid chromatography (DHPLC). METHODS: A mutation analysis on five Japanese patients with Menkes disease was performed using a direct sequencing method and DHPLC. RESULTS: Two nonsense mutations, two missense mutations and one splice donor site mutation were found. The DHPLC analysis showed differences in the peaks between the DNA fragments of wild type and heteroduplex (wild type and mutant). CONCLUSIONS: Three novel mutations (Asp1044Gly, Pro1279Leu and IVS21+1 g to a) were detected. The Asp1044Gly mutation destroys the highly conserved phosphorylation domain in exon 16. The splice site abnormality leads to a skipping of exon 21 coding for part of the seventh transmembrane domain. These two mutations could cause a severe protein dysfunction. Another missense mutation, Pro1279Leu, in exon 20 was found in a patient with a mild type of Menkes disease. It is speculated that this mutation partially maintains the ATP7A function is. A DHPLC analysis could detect these mutations. It is concluded that the best way to make a molecular diagnosis for Menkes disease is to first screen DNA samples for all exons using DHPLC, and thereafter perform direct sequencing for exons which have an abnormal elution profile in order to rapidly detect such mutations.

Case-Control Studies↗
PubMed2005

[A case of Crigler-Najjar syndrome type I: long survival with bilirubin adsorption and liver transplantation].

Crigler-Najjar syndrome type I is an autosomal recessive disorder with severe unconjugated hyperbilirubinemia, caused by the complete absence of bilirubin uridine 5'-diphosphate-glucuronosyltransferase (UGT) activity. The authors reported a 24-year-old male with this syndrome. He had severe icterus from the age of 4 days, and was diagnosed as having Crigler-Najjar syndrome type I at 51 days after birth. Despite repeated phototherapy, his serum bilirubin was increased. When bilirubin encephalopathy occurred at the age of 16 years, the serum bilirubin level was 47 mg/100 ml. EEG showed diffuse and continuous high voltage slow waves. He was treated with bilirubin adsorption, which reduced the serum bilirubin level to 10-20 mg/100 ml, with disappearance of the EEG abnormality. Subsequent liver transplantation resulted in improvement of neurological signs and symptoms, and recovery of his mental function.

Adsorption↗
PubMed2004

[Wilson disease].

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Adenosine Triphosphatases↗
PubMed2003

Removal of protein-bound and unbound unconjugated bilirubin by perfusion of plasma through an anion-exchange resin in a case of Crigler-Najjar syndrome type I.

BACKGROUND: Patients with Crigler-Najjar syndrome, type I (CNS-I) have an inherited absence of hepatocellular bilirubin uridine diphosphate-glucuronosyltransferase activity, which results in severe unconjugated hyperbilirubinaemia, often causing kernicterus and death in infancy or childhood. METHODS: Our patient is a 19-year-old Japanese man with CNS-I diagnosed by the complete absence of the hepatocellular enzyme in a liver biopsy and genotyping. The efficacies of the removal of protein-bound (PBB) and unbound (UB) unconjugated bilirubin by phototherapy, plasma perfusion and liver transplantation were compared in the patient. RESULTS: At the age of 5 years, phototherapy treatment reduced the patient's PBB by 21% and UB by 34%, and 98% of the bilirubin produced daily was removed. At the age of 16 years, plasma perfusion combined with nightly phototherapy completely removed the daily production of bilirubin; however, by 24 h post-treatment, the PBB and UB were again increased. Apparently, these treatments were effective in reducing PBB and UB, but the effect was only temporary. Following liver transplantation, PBB and UB decreased to normal concentrations. CONCLUSIONS: Liver transplantation as a potential cure should be performed at a younger age, particularly in confirmed CNS-I cases for which reliable effects of phototherapy cannot be guaranteed.

Adolescent↗
PubMed2002

Two families with Wilson disease in which siblings showed different phenotypes.

We investigated two families with Wilson disease in which siblings showed different clinical phenotypes and different ages at onset. In Family 1, the second and fourth male children demonstrated onset of the neurological type of Wilson disease at 16 and 28 years of age, respectively, and the first female child developed the hepatic type at 38 years of age. In Family 2, the second male child showed neurological symptoms at 32 years of age and was diagnosed as having the hepatoneurological type of Wilson disease; then the 35-year-old first female child was found to have the hepatic type by familial screening. We performed mutation analysis of the ATP7B gene for these patients, and found that the mutation was a compound heterozygote in both families. Previous reports of siblings with Wilson disease have shown an identical clinical phenotype and similar ages at onset. In addition, hepatic-type cases generally occur at lower ages compared with the neurological type. In the present investigation, however, younger patients showed neurological symptoms earlier than their older siblings, and clinical phenotypes differed among siblings in both families. These cases appear to be rare. Individual differences in copper accumulation in hepatic cells and intolerance to copper toxicity might be the reason for this phenomenon. Furthermore, there might be a difference in the dominance of the allele expressing ATP7B protein among these cases, resulting in different clinical phenotypes, because all patients of both families were found to be compound heterozygotes.

Adenosine Triphosphatases↗
PubMed2002

Factor VII deficiency and a copper metabolism disorder in a patient with Klippel-Trenaunay syndrome.

We report on a patient with Klippel-Trenaunay (KT) syndrome, a factor VII deficiency and a copper metabolism disorder. The KT syndrome involved the left leg and, histologically, the liver. Dermatological examination, duplex ultrasonography and a skin and liver biopsy verified the KT syndrome. A long prothrombin time prompted clotting studies revealing a factor VII deficiency while the other factors were in the normal range. Further laboratory examinations showed a copper metabolism disorder similar to Wilson's disease with a low serum ceruloplasmin level, elevated copper concentration in the urine and increased copper deposition in the liver. Neither liver cirrhosis nor a Kayser-Fleischer corneal ring was present. Sequencing analysis of the Wilson's disease gene ATB7B showed no mutations. The occurrence of these three uncommon pathologies in a single patient has not been described to date, which may suggest a mutation in a hypothetical common regulatory gene leading to this unusual phenotype.

Adult↗
PubMed2002

[Wilson disease].

Explore the source record for details and available documents.

Adenosine Triphosphatases↗