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Y Ochiai

Publications and source records attributed to Y Ochiai.

At least 55 records · Page 3Linked to original sources

[The prevalence rate and etiology of severe motor and intellectual disabilities syndrome in Okinawa].

We studied sixty-three children of severe motor and intellectual disabilities syndrome aged between 3 and 5 years, who live in Okinawa. Severe motor and intellectual disabilities syndrome were defined as those who belong to classes 1 approximately 4 of Ohshima's classification (incapable of walking with IQs not more than 35). The prevalence rate was about 1.12/1,000 live births. Forty-four% of the total children belonged to class 1 of Ohshima's classification (bedridden and IQs less than 20). The factors were: congenital 31.7%, perinatal 38.1%, postnatal 14.3%, and unknown 15.9%. The perinatal factor was still relatively high as compared with the others.

Child, Preschool↗

Chromosomal mapping of the human smooth muscle actin gene (enteric type, ACTA3) to 2p13.1 and molecular nature of the hindIII polymorphism.

The human gene for smooth muscle actin (enteric type, ACTA3) has been isolated, and three overlapping clones, lambda HACTSG-17, -2, and -112, were used as probes for fluorescence in situ hybridization of human chromosomes. The gene was localized to chromosome 2p13.1. To clarify the molecular nature of the HindIII RFLP present in the first intron of the gene, the 1105-bp EcoRI-BamHI fragment contained in lambda HACTSG-17 was sequenced. PCR with primers designed from the determined sequence yielded either the 463- or the 439-bp product or both, using human DNA as template. The 463-bp product was cleavable with HindIII, but the 439-bp product was not. Comparison of their nucleotide sequences revealed that they differ in the presence/absence of a 24-bp sequence harboring a HindIII restriction site. Therefore, analysis of PCR products by size has been shown to be sufficient to detect the RFLP. The allelic frequency on 156 chromosomes was determined by PCR to be 45 (439 bp, corresponding to the formerly designated A1 allele):55 (463 bp, A2 allele) in the Japanese population.

Actins↗

Muscle and intramuscular nerve pathology in congenital hypomyelination neuropathy.

Two patients had delayed development and generalized muscle hypotonia and weakness since early infancy. Their muscle biopsies showed slight variation in fiber size without group atrophy, and no clear evidence of an active demyelinating process in the intramuscular nerves. The most striking finding by light microscopy was the absence of myelinated fibers in the intramuscular nerve bundles. Ultrastructurally, the axons were devoid of myelin sheath or had very thin myelin sheaths, and the axons were surrounded by multilayered basal lamina forming an atypical onion bulb with no suggestions of myelin destruction. A sural nerve biopsy from one of the patients showed similar findings. Unlike the Déjèrine-Sottas type of hereditary motor and sensory neuropathy, there was no evidence of demyelination and remyelination in the muscle pathology, suggesting that the poor myelination in congenital hypomyelination neuropathy is due to a true "hypo"-myelination and not the result of demyelination.

Biopsy↗

Human seminal plasma beta-microseminoprotein: its purification, characterization, and immunohistochemical localization.

beta-Microseminoprotein was very efficiently purified from human seminal plasma with only three steps including DEAE-Sephacel and Zinc-chelate Sepharose CL-6B column chromatography. The purified protein was a non-glycoprotein with a molecular weight (M(r)) of 19,000 and 17,000 on gel filtration and reduced SDS-PAGE, respectively. The protein gave six bands from M(r) 15,600 to 25,500 on non-reduced SDS-PAGE. The characterization including the molecular weight, amino acid sequence of N-terminus and concentrations in various body fluids is discussed. Furthermore, the immunohistochemical localization of the protein among various human tissues is demonstrated.

Amino Acid Sequence↗

Human gene for beta-microseminoprotein: its promoter structure and chromosomal localization.

The gene for human beta-microseminoprotein (MSP, beta-inhibin, prostatic secretory protein94, or PSP94) was isolated. The nucleotide sequence of its upstream region (2,860 bp), exon 1 (35 bp), and a part of the following intron (218 bp) was determined. Transient transfection analysis on MSP-expressing (PC-3) and -nonexpressing (HepG2) cells using luciferase reporter plasmids suggested that the region from -2738 to -276 is not essential for the basal promoter activity, and that the regions from -275 to -207 and from -186 to -128 function in a cell-specific manner. The chromosome locus of the gene (MSMB) was determined through application of PCR to the DNAs of rodent-human somatic cell hybrids and also by the fluorescence in situ hybridization technique to be region q11.2 of chromosome 10.

Animals↗

[Symmetrical thalamic lesions due to perinatal brain damage].

There have been many reports concerning cases with basal ganglionic and thalamic lesions due to neonatal hypoxic-ischemic encephalopathy (HIE), which are considered as a clinicopathological syndrome. But the clinical symptoms and extension of the brain damage varied from case to case. We previously reported seven cases with bilateral basal ganglionic and thalamic lesions (BBTL) due to neonatal HIE. The affected lesions were posterior putamen, lateral thalami, hippocampus and perirolandic cortex. Now, we have experienced two cases who presented symmetrical thalamic lesions (STL) with involvement of the brainstem and periventricular white matter due to neonatal HIE. Of these lesions of the basal ganglia and thalamus, STL comprised calcification and atrophy of the bilateral thalami, and BBTL comprised cystic lesions of the bilateral putamen and thalami. The cerebral lesion in the cases of BBTL were observed in the perirolandic cortex, which is a watershed area of the main vascular territories. While the cerebral lesion in the cases of STL were found in the periventricular white matter, which is a watershed area in premature babies. The brainstem was more severely injured in the case of STL than BBTL. The distribution of the affected lesions suggested that the cases with STL had a different clinicopathological syndrome from those with BBTL. We discussed the developmental mechanism of the cases.

Basal Ganglia Diseases↗

[Pattern of the brain damages and its developmental mechanisms in monozygotic twins].

Neurologic morbidity is observed more frequently in twins than in singletons. Low birthweight and premature birth are observed more frequently in twins but cannot always explain the cause of cerebral palsy, although circumstances related to twinning may cause brain damage. We attempted to select the patients whose brain damages might be caused by circumstances related to twinning and discussed the developmental mechanisms of their brain damages. We divided the cases into 3 groups. One comprised the monozygotic (MZ) twins whose co-twins had died. The second comprised the MZ twins with the complication of the twin-twin transfusion syndrome or discordant twins. The third comprised the MZ twins with concordant co-twins. We postulated that group I and II had complication of the disturbance of fetal circulation, but group III did not. Hydranencephaly (group I) and polymicrogyria (group II) might develop when the disruption occurs at an intermediate stage of morphogenesis (before the 6th month of gestation). In the cases with cerebral infarction (group I), the distribution of the lesions were related to the main vascular territories of the mature form, might be caused by occlusion of blood vessels associated with intrauterine disseminated intravascular coagulation. In the cases of MCE (group I), multiple cavities are present mainly in the white matter, the gray matter having a tendency to be spared. As the distribution of the cavities is not related to the main vascular territories, it was less likely that the lesions was produced by occluded vessels. The death of one fetus might cause severe blood deprivation, leading to hypoxic-ischemic brain insults in the surviving fetus.(ABSTRACT TRUNCATED AT 250 WORDS)

Brain↗

Scallop striated and smooth muscle myosin heavy-chain isoforms are produced by alternative RNA splicing from a single gene.

We report here that the catch and striated adductor muscle myosin heavy-chain (MHC) isoforms of scallop (Argopecten irradians, previously Aequipecten irradians) are generated by alternative RNA splicing from a single gene. Scallop catch muscle cDNA and genomic DNA were amplified by PCR using primers based on the previously sequenced scallop striated muscle MHC cDNA. Mapping of the exon/intron borders and sequencing of a full-length catch muscle MHC in overlapping fragments revealed that the 24-kb gene encodes the MHC polypeptide in 27 exons and that four sets of tandem exon pairs are alternatively spliced into a striated and a catch MHC isoform. An additional alternative exon was identified in catch cDNA and is apparently spliced into a minor MHC isoform. The striated muscle-specific isoform is not expressed in other tissues, whereas the catch-type isoforms were also detected in various smooth muscles, but not in the striated one. Of the alternative exons, exons 5 and 6 encode part of the ATP-binding region and the 25-kDa/50-kDa proteolytic junction; exon 13 encodes part of one of the actin-binding regions and extends to the active site; exon 20 encodes the middle of the rod hinge region; exon 26 in the striated-specific sequence starts with the stop codon, whereas the catch-specific exon codes for an additional 10 residues. Differences between the alternative exons presumably determine the lower ATPase activity of smooth muscle myosin, contribute to the different structure of the striated and smooth muscle thick filaments, and may also be important for the molecular mechanism of the catch phenomenon.

Alternative Splicing↗

Dipeptidyl peptidase IV from porcine seminal plasma: purification, characterization, and N-terminal amino acid sequence.

Dipeptidyl peptidase IV (DPP IV) was purified to homogeneity from porcine seminal plasma by polyacrylamide gel electrophoresis (PAGE). The molecular weight of the purified enzyme was calculated to be approximately 290,000 on PAGE in the absence of sodium dodecyl sulfate (SDS) and 310,000 on Sephacryl S-300 HR column chromatography, and to be 115,000 and 105,000 on SDS-PAGE in the absence and presence of beta-mercaptoethanol. The enzyme is suggested to be composed of three identical subunits. The enzyme rapidly hydrolyzed the substrate Gly-Pro-MCA, and weakly the substrate Lys-Ala-MCA. It was strongly inhibited by diisopropylphosphofluoridate (DFP), and moderately by both phenylmethyl-sulfonyl fluoride (PMSF) and 4-(2-aminoethyl)-benzenesulfonyl fluoride (AEBSF). It was also strongly inhibited by zinc ion. The amino acid sequence of the first 18 residues of the enzyme was Asn-Lys-Gly-Thr-Asp-Asp-Ala-Ala-Ala-Asp-Ser-Arg-Arg- Thr-Tyr-Thr-Leu-Thr-. This sequence was highly homologous to the sequences in the rear of the transmembrane site of human and rat liver DPP IVs and mouse thymus DPP IV. The native DPP IV is suggested to be released into the seminal plasma after the cleavage of the hydrophobic N-terminal domain by chymotrypsin-like or pepsin-like enzymes. Other properties of DPP IV including kinetic parameters, pH stability and heat stability were characterized.

Amino Acid Sequence↗

[Epilepsy in patient with structural autosomal abnormality].

Few cases have been reported on the structural autosomal abnormality (SAA) focusing on epilepsy excluding those of Down syndrome and Klinefelter syndrome. We investigated patients who had SAA with special reference to epilepsy. Various types of epilepsy were observed in its severity in our cases as well as previously reported cases. There was no correlation between the degree of mental retardation, motor dysfunction, brain damage on CT scan, and severity of epilepsy. Some cases had brain dysplasia, such as agenesis of corpus callosum, pachygyria, and mega cisterna magna. No correlation was found between these brain dysplasia and severity of epilepsy. It is important for a pediatrician to find a common epileptic syndrome or EEG abnormality in a SAA. An observation of symptoms in patients with the same chromosomal deletion or duplication will lead to identification of responsible gene for an epileptic symptom.

Adolescent↗

[Clinical consideration of patients with neonatal bilateral basal ganglia-thalamic lesion due to hypoxic ischemic encephalopathy].

We describe herein the clinical symptoms, clinical course and results of investigation of 7 patients with bilateral basal ganglia-thalamic lesions (BBTL). All patients had spastic quadriplegia with rigidity. They were unable to sit and turn over. They could follow objects, turn head towards a sound and recognize parents to some degree. They were all evaluated as having the most severe degree of disability (Oshima's classification 1). They all had dysphagia and 2 patients had a episode of bradycardia and hypothermia, which might be evidences of brain stem disorders. Muscle hypertonia, vomiting, hematemesis and obstructive respiration, which were the major complications for the patients, worsened with age. High percentage of histories of birth asphyxia and poor feeding in the neonatal period suggested that perinatal brain insults might be one of the important factors for developing BBTL. It seemed to be difficult to explain that such diffuse brain injuries in our cases were caused by only the insults during parturition. Brain insults during parturition as well as prenatal factors probably participate in developing BBTL. Although the cerebrum of the patients seem to be relatively preserved in the images of head CT-scan, MRI of the patients revealed diffuse brain lesions. All of five patients tested had an abnormal auditory brain stem response (ABR). These investigations demonstrated that patients with BBTL have diffuse brain damage including brain stem. Further observation is needed to verify the mechanisms of development and the time of onset of BBTL.

Adolescent↗