Tohoku University

About: Tohoku University is a education organization based out in Sendai, Japan. It is known for research contribution in the topics: Magnetization & Alloy. The organization has 72116 authors who have published 170791 publications receiving 3941714 citations. The organization is also known as: Tōhoku daigaku.

Rabbit very low density lipoprotein receptor: a low density lipoprotein receptor-like protein with distinct ligand specificity.

Abstract: A cDNA that expresses a receptor for very low density lipoprotein (VLDL) was isolated from a rabbit heart cDNA library and characterized. The deduced amino acid sequence of the cDNA revealed that the cDNA encodes a protein with striking homology to the low density lipoprotein (LDL) receptor. Like the LDL receptor, the mature protein consists of the following five domains spanning 846 amino acids: 328 N-terminal amino acids including an 8-fold repeat of 40 amino acids homologous to the ligand binding repeat of the LDL receptor; 396 amino acid residues homologous to the epidermal growth factor precursor including three cysteine-rich repeats; a region immediately outside of the plasma membrane rich in serines and threonines; 22 amino acids traversing the plasma membrane; and 54 amino acids including the NPVY sequence that is required for clustering of the LDL receptor in coated pits and that projects into the cytoplasm. LDL-receptor-deficient Chinese hamster ovary cells transfected with the cDNA bound and internalized VLDL, beta-migrating VLDL, and intermediate density lipoprotein but did not bind LDL with high affinity. The 3.6- and 9.5-kilobase mRNAs for the VLDL receptor are highly abundant in heart, muscle, and adipose tissue. Barely detectable amounts of the mRNAs were present in liver. Based on the structural features, ligand specificity, and tissue expression of the mRNAs, we suggest that this VLDL receptor may mediate uptake of apolipoprotein E-containing lipoproteins enriched with triglyceride in nonhepatic tissues that are active in fatty acid metabolism.

Anti-aquaporin-4 antibody is involved in the pathogenesis of NMO: a study on antibody titre.

Abstract: NMO-IgG is a disease-specific autoantibody for neuromyelitis optica (NMO) and its target antigen is aquaporin-4 (AQP4) water channel. Recently, we established a sensitive anti-AQP4 antibody assay using human AQP4-transfected cells, which appeared more sensitive than the original NMO-IgG assay. So far, there has been no large-scale study on anti-AQP4 antibody titre in NMO and related disorders. We tested 148 sera of patients with NMO, high-risk syndrome of NMO, multiple sclerosis (MS), clinically isolated syndrome suggestive of MS and miscellaneous diseases. We analysed the relation of anti-AQP4 antibody titres and clinical and laboratory parameters. The sensitivity of anti-AQP4 antibody assay was 91% (95% CI 79-100) for NMO and 85% (65-100) for high-risk syndrome, and the specificity was 100% (91-100) for NMO and high-risk syndrome, that is, none with the other disorders was positive. Among 21 anti-AQP4 antibody-positive cases whose NMO-IgG were tested, 15 were NMO-IgG-positive and 6 were NMO-IgG-negative. Higher anti-AQP4 antibody titres were associated with complete blindness and extensive or large cerebral lesions on MRI. The lengths of spinal cord lesions on MRI were positively correlated with the titres of anti-AQP4 antibody at the nadir of exacerbations. A few patients who had short (approx. one to two vertebral segments) spinal cord lesions on MRI were also seropositive with low anti-AQP4 antibody titres, but did have other clinical and MRI features of NMO. Anti-AQP4 antibody titres became lower after high-dose methylprednisolone, and a follow-up showed anti-AQP4 antibody titres remained low in relapse-free periods under immunosuppression. Cerebrospinal fluid (CSF)-anti-AQP4 antibody was detected when the serum-antibody titres exceeded 512x, at the ratio of 1 (CSF) to 500 (serum). Using a sensitive assay, the results of the present study suggest that NMO and high-risk syndrome may be essentially anti-AQP4 antibody-associated disorders, and that the anti-AQP4 antibody titres have significant clinical and immunological implications in NMO.

Detection of p53 Gene Mutations in Human Brain Tumors by Single-strand Conformation Polymorphism Analysis of Polymerase Chain Reaction Products

Abstract: The normal (wild-type) p53 product acts as a suppressor of transformation [1], while mutated p53 proteins may inactivate the wild-type p53 function resulting in cell transformation [2] Mutations of the p53 gene have been found in conjunction with chromosome 17p allelic deletions in many human tumors [3,4]

Germline KRAS and BRAF mutations in cardio-facio-cutaneous syndrome

Abstract: Cardio-facio-cutaneous (CFC) syndrome is characterized by a distinctive facial appearance, heart defects and mental retardation. It phenotypically overlaps with Noonan and Costello syndrome, which are caused by mutations in PTPN11 and HRAS, respectively. In 43 individuals with CFC, we identified two heterozygous KRAS mutations in three individuals and eight BRAF mutations in 16 individuals, suggesting that dysregulation of the RAS-RAF-ERK pathway is a common molecular basis for the three related disorders.