Publications by authors named "Taro Yamazaki"

Article Synopsis
  • Prenatal genetic diagnosis of mitochondrial diseases caused by defects in nuclear DNA (nDNA) has been studied in various countries, but not yet in Japan.
  • In a study involving over 400 patients, 13 families sought prenatal diagnosis, with some pregnancies leading to the birth of healthy babies after being diagnosed with benign variants.
  • The findings suggest that severe mitochondrial diseases with potential lethality could benefit from prenatal testing, highlighting the need for careful genetic counseling for families considering their options.
View Article and Find Full Text PDF

Leigh syndrome is a major phenotype of mitochondrial diseases in children. With new therapeutic options being proposed, assessing the mortality and clinical condition of Leigh syndrome patients is crucial for evaluating therapeutics. As data are scarce in Japan, we analysed the mortality rate and clinical condition of Japanese Leigh syndrome patients that we diagnosed since 2007.

View Article and Find Full Text PDF

Sapropterin dihydrochloride (SD) may be a new treatment option for women with phenylketonuria (PKU) who plan to become pregnant. We report the first Japanese case of maternal PKU treated with SD. The patient was administered SD at 10-20 mg/kg/day, which increased phenylalanine tolerance during the pregnancy and lactation.

View Article and Find Full Text PDF

Leigh syndrome (LS) is a progressive neurodegenerative disorder of infancy and early childhood. It is clinically diagnosed by typical manifestations and characteristic computed tomography (CT) or magnetic resonance imaging (MRI) studies. Unravelling mitochondrial respiratory chain (MRC) dysfunction behind LS is essential for deeper understanding of the disease, which may lead to the development of new therapies and cure.

View Article and Find Full Text PDF

Background: A nationwide, multicenter and observational study was retrospectively conducted to evaluate the clinical utility of Cepharanthin (CEP) for pediatric patients with chronic immune thrombocytopenia (ITP).

Methods: Clinical and laboratory data for 46 Japanese patients aged <16 years who were diagnosed as having chronic ITP in 14 hospitals during 2001-2011, and were treated with CEP for >12 months, were analyzed.

Results: Median daily CEP dose was 1 mg/kg (range, 0.

View Article and Find Full Text PDF

Chloramphenicol (CP) is recently one of the rarely-used antibiotics. In this study, we present four patients with intractable bacterial meningitis, who were successfully treated with CP and discuss the therapeutic indications of CP in these pediatric cases. The patients were diagnosed as bacterial meningitis at the ages ranging from 2 months to 1 year and 4 months.

View Article and Find Full Text PDF

Mitochondrial disorders have the highest incidence among congenital metabolic disorders characterized by biochemical respiratory chain complex deficiencies. It occurs at a rate of 1 in 5,000 births, and has phenotypic and genetic heterogeneity. Mutations in about 1,500 nuclear encoded mitochondrial proteins may cause mitochondrial dysfunction of energy production and mitochondrial disorders.

View Article and Find Full Text PDF

We report on the clinical, neuropathological, and genetic findings of a Japanese case with myocerebrohepatopathy spectrum (MCHS) disorder due to polymerase gamma (POLG) mutations. A girl manifested poor sucking and failure to thrive since 4 months of age and had frequent vomiting and developmental regression at 5 months of age. She showed significant hypotonia and hepatomegaly.

View Article and Find Full Text PDF

Objective: Mitochondrial respiratory chain disorder (MRCD) is an intractable disease of infants with variable clinical symptoms. Our goal was to identify the causative mutations in MRCD patients.

Methods: The subjects were 90 children diagnosed with MRCD by enzyme assay.

View Article and Find Full Text PDF

Background: Although mitochondrial respiratory chain disorders (MRCD) are one of the most common congenital metabolic diseases, there is no cumulative data on enzymatic diagnosis and clinical manifestation for MRCD in Japan and Asia.

Methods: We evaluated 675 Japanese patients having profound lactic acidemia, or patients having symptoms or signs of multiple-organ origin simultaneously without lactic acidemia on respiratory chain enzyme activity assay and blue native polyacrylamide gel electrophoresis. Quantitative polymerase chain reaction was used to diagnose mitochondrial DNA depletion syndrome (MTDPS).

View Article and Find Full Text PDF

Mutations in the polymerase γ (POLG) gene are among the most common causes of mitochondrial disease and more than 160 POLG mutations have been reported. However, a large proportion of patients suspected of having POLG mutations only have one (heterozygous) definitive pathogenic mutation identified. Using oligonucleotide array CGH, we identified a compound heterozygous large intragenic deletion encompassing exons 15-21 of this gene in a child with Alpers syndrome due to mtDNA depletion.

View Article and Find Full Text PDF