Hirosaki University

About: Hirosaki University is a education organization based out in Hirosaki, Japan. It is known for research contribution in the topics: Population & Cancer. The organization has 7922 authors who have published 14344 publications receiving 277097 citations. The organization is also known as: Hirosaki Daigaku.

Genetics of Idiopathic Epilepsies

Abstract: Summary: Purpose: To search for clues to molecular genetics of common idiopathic epilepsy syndromes. Genetic defects have been identified recently in certain inherited epilepsy syndromes in which the phenotypes are similar to those of common idiopathic epilepsies. Methods: Mutations identified as the causes of inherited idiopathic epilepsies were reviewed. Results: Mutations of the genes encoding two subunits of the neuronal nicotinic acetylcholine receptor were found in autosomal dominant nocturnal frontal lobe epilepsy. Mutations of two K+-channel genes were identified in benign familial neonatal convulsions. Mutations of the genes encoding several subunits of the voltage-gated Na+-channel and γ-aminobutyric acid (GABA)A receptor also were identified as the underlying causes of various epilepsy syndromes, such as autosomal dominant epilepsy with febrile seizures plus, benign familial neonatal infantile seizures, and autosomal dominant juvenile myoclonic epilepsy. Mutations within the same gene may result in different epilepsy phenotypes. Thus, the Na+ channel, GABAA receptor, and their auxiliaries may be involved in the pathogenesis of various types of epilepsy. Some forms of juvenile myoclonic epilepsy, idiopathic generalized epilepsy, and absence epilepsy may result from mutations of Ca2+ channels. Mutations of the Cl− channel have been recently found to be associated with a certain type of epilepsy. The recent discovery that mutations of LGI1, a gene encoding a nonchannel molecule, are associated with autosomal partial epilepsy with auditory features may provide a new insight into our understanding of the genetics of idiopathic epilepsy. Conclusions: These findings suggest the involvement of brain channelopathies in the pathogenesis of certain types of idiopathic epilepsy.

Muscular atrophy in the hemiplegic thigh in patients after stroke.

Abstract: Metoki N, Sato Y, Satoh K, Okumura K, Iwamoto J: Muscular atrophy in the hemiplegic thigh in patients after stroke. Am J Phys Med Rehabil 2003;82:862–865. This study evaluated muscular atrophy in the hemiplegic limbs by assessing the muscle volume of the thighs in stroke patients. Muscle volume of the bilateral thighs was determined by computed tomographic scanning in 50 hemiplegic patients after stroke. The average muscle volume in the hemiplegic side was significantly lower than that in the nonhemiplegic side. When the patients were divided into the two groups aged <65 yr old and ≥65 yr, age-dependent reduction in the muscle volume was significant only in the nonhemiplegic side. In addition, the ratio of the muscle volume in the hemiplegic side to that in the nonhemiplegic side was significantly lower in the older group than in the younger group. Muscle volume in both hemiplegic and nonhemiplegic sides correlated positively with Barthel index and negatively with patient age. Muscle volume decreases in the hemiplegic side in stroke patients.

Identification and Characterization of a Novel Staphylococcal Emetic Toxin

Abstract: Staphylococcal enterotoxins (SEs) produced by Staphylococcus aureus have superantigenic and emetic activities, which cause toxic shock syndrome and staphylococcal food poisoning, respectively. Our previous study demonstrated that the sequence of SET has a low level of similarity to the sequences of other SEs and exhibits atypical bioactivities. Hence, we further explored whether there is an additional SET-related gene in S. aureus strains. One SET-like gene was found in the genome of S. aureus isolates that originated from a case of food poisoning, a human nasal swab, and a case of bovine mastitis. The deduced amino acid sequence of the SET-like gene showed 32% identity with the amino acid sequence of SET. The SET-like gene product was designated SElY. In the food poisoning and nasal swab isolates, mRNA encoding SElY was highly expressed in the early log phase of cultivation, whereas a high level of expression of this mRNA was found in the bovine mastitis isolate at the early stationary phase. To estimate whether SElY has both superantigenic and emetic activities, recombinant SElY was prepared. Cell proliferation and cytokine production were examined to assess the superantigenic activity of SElY. SElY exhibited superantigenic activity in human peripheral blood mononuclear cells but not in mouse splenocytes. In addition, SElY exhibited emetic activity in house musk shrews after intraperitoneal and oral administration. However, the stability of SElY against heating and pepsin and trypsin digestion was different from that of SET and SEA. From these results, we identified SElY to be a novel staphylococcal emetic toxin.