Toxic myopathy with multiple deletions in mitochondrial DNA associated with long-term use of oral anti-viral drugs for hepatitis B: A case study.

Oral nucleoside analogs (NAs) reduce hepatitis B virus (HBV) replication by inhibiting HBV DNA polymerase. However, NAs can also affect human mitochondrial DNA (mtDNA) polymerase, which can lead to mtDNA depletion (quantitative abnormality). Indeed, several mitochondrial myopathy cases have been reported in which a reduced mtDNA copy number was induced by oral NAs for hepatitis B.

Streptococcus pyogenes-purpura fulminans as an invasive form of group A streptococcal infection.

Background: Streptococcus pyogenes is an uncommon pathogen of purpura fulminans, and the pathogenesis of S. pyogenes-purpura fulminans remains unclear because of paucity of cases. We reported a pediatric case of S.

The clinical presentation and genotype of protein C deficiency with double mutations of the protein C gene.

Background: Severe protein C (PC) deficiency is a rare heritable thrombophilia leading to thromboembolic events during the neonatal period. It remains unclear how individuals with complete PC gene (PROC) defects develop or escape neonatal stroke or purpura fulminans (PF).

Procedure: We studied the onset of disease and the genotype of 22 PC-deficient patients with double mutations in PROC based on our cohort (n = 12) and the previous reports (n = 10) in Japan.

Fetal hydrocephalus and neonatal stroke as the first presentation of protein C deficiency.

Severe protein C-deficiency is a rare heritable thrombophilia of the newborn. Infants with biallelic PROC mutations present purpura fulminans and intracranial thromboembolism, while the prenatal onset of mutated heterozygotes remains unclear. We herewith present the first case of fetal ventriculomegaly and neonatal stroke associated with heterozygous PROC mutation.

[Analysis of influenza A/H3N2 neuraminidase genes obtained from influenza patients in the 2011/12 and 2012/13 seasons in Japan].

Background: Influenza virus has neuraminidase (NA), a surface protein with enzymatic activity that is essential for virus replication. Mutation may affect the effectiveness of NA inhibitors that are used for the treatment of influenza patients. In this study, we determined the NA gene sequences from the clinical isolates of influenza patients to examine the chronological genetic changes and the relation to drug susceptibility.

A novel mutation in protein C gene (PROC) causing severe phenotype in neonatal period.

Homozygous protein C deficiency is among rare causes of thrombophilia. Herein, we present a neonate with purpura fulminans, disseminated intravascular coagulation and severe intracranial hemorrhage who was found to have plasma protein C level of 4%. The molecular work-up revealed a novel homozygous mutation of T903C (amino acid position Leu 270 Pro) located in a catalytic domain region of PROC gene.

[A case of sensory ataxic neuropathy, dysarthria, and ophthalmoparesis with multiple mitochondrial DNA deletions].

We report the case of a 62-year-old man with sensory ataxic neuropathy, dysarthria, and ophthalmoparesis (SANDO). He developed gait disturbance at 54 years of age, muscle weakness at 56 years, and difficulty hearing at 58 years. His brother had muscle weakness in both legs from age 20 years, and was diagnosed with Charcot-Marie-Tooth disease because he had muscle weakness of the four extremities, decreased CMAP and SNAP amplitudes on peripheral nerve conduction tests, and loss of large myelinated fibers and onion-bulb formations on sural nerve biopsy.

Platelet contamination causes large variation as well as overestimation of mitochondrial DNA content of peripheral blood mononuclear cells.

Background: Alterations in the copy number of mitochondrial DNA (mtDNA) play a role in the pathogenesis of mitochondrial diseases and other many common diseases. Recently, the copy number of leukocyte mtDNA has been considered to serve as a biomarker to monitor or chase such diseases. Therefore, reproducible mtDNA measurement is required.

Fulminant sepsis/meningitis due to Haemophilus influenzae in a protein C-deficient heterozygote treated with activated protein C therapy.

A 13-month-old Japanese female with Haemophilus influenzae type b meningitis presented with unusually severe septic shock and cerebral infarction in half a day of fever. The initial therapy of plasma-derived activated protein C (Anact C) led to an impressive effect on the aggressive condition. However, purpura fulminans and the consistent decline of plasma protein C activity (<20%) required prolonged activated protein C therapy and gene analysis.

High-sensitivity detection of the A3243G mutation of mitochondrial DNA by a combination of allele-specific PCR and peptide nucleic acid-directed PCR clamping.

Background: The A3243G mutation of mitochondrial DNA (mtDNA) is involved in many common diseases, including diabetes mellitus and mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS). For detection of this mutation, allele-specific PCR is highly sensitive but requires strict control of PCR conditions; it thus is not adequate for a routine clinical test. We aimed to develop a routinely available PCR method for quantitative detection of low-level heteroplasmy of the A3243G mutation.

[A basic study of determination matrix metalloproteinase-3 and carbohydrate in rheumatoid factor in serum for diagnosis of rheumatoid arthritis].

The examination of rheumatoid factor (RF), one of the diagnostic marker of rheumatoid arthritis (RA), showed negative about 25% of patients with RA. We analyzed a matrix metalloproteinase-3 (MMP-3) and a carbohydrate in rheumatoid factor (CA.RF) for diagnosis of RA: the former is used the kit "Panaclear MMP-3[Plate]" and the latter is used the kit "Picolumi CA.

Four missense mutations identified in the protein S gene of thrombosis patients with protein S deficiency: effects on secretion and anticoagulant activity of protein S.

Four missense mutations, G54R, T589I, K155E, and Y595C, were identified in the protein S (PS) gene of the patients with PS deficiency and venous thrombosis. Three patients were heterozygous for the novel mutations, G54R, T589I, and Y595C, while a remaining one patient was homozygous for the K155E mutation, which is known to be a polymorphism in the Japanese population. A family study revealed that the Y595C mutation was associated with a Type I PS deficiency and the K155E mutation with a Type II PS deficiency, while no family study was performed for the patients with the G54R and T589I mutations.