Biomedical subjects

T Yanagihara

Publications and source records attributed to T Yanagihara.

At least 199 records · Page 11Linked to original sources

PubMed1993

Differential vulnerability in the hindbrain neurons and local cerebral blood flow during bilateral vertebral occlusion in gerbils.

Differential vulnerability in the hindbrain neurons was examined immunohistochemically during hindbrain ischemia in the gerbil. Hindbrain ischemia was produced by extracranial occlusion of the bilateral vertebral arteries just before their entry into the transverse foramen of the cervical vertebra. Local cerebral blood flow was measured by quantitative autoradiographic technique after 5 min of ischemia and was reduced to less than 5 ml/100 g per min in the cerebellum, the pons, and the medulla, indicating that severe and reproducible hindbrain ischemia was induced immediately after occlusion. For immunohistochemical investigation, four gerbils each were used for each ischemic period of 5, 10, 15, and 30 min. Immunohistochemical lesions, detected by the reaction for microtubule-associated protein 2, were visible in the lateral vestibular nucleus and the cerebellar interpositus nucleus even after 5 min of ischemia. These results suggested that these areas were more vulnerable than others, although blood flow was markedly reduced in various regions of the hindbrain. In contrast, areas related to respiratory or cardiovascular control were rather resistant to ischemia. The present study suggests that selective vulnerability during hindbrain ischemia depends mainly on different metabolic characteristics inherent to various neurons in the hindbrain.

Animals↗

PubMed1993

Trypsin-like protease of mites: purification and characterization of trypsin-like protease from mite faecal extract Dermatophagoides farinae. Relationship between trypsin-like protease and Der f III.

A serine protease from mite faecal extract, Dermatophagoides farinae, was purified using DEAE-Sephacel anion exchange chromatography and Superdex 75 pg gel chromatography. The molecular weight of this protease was 34 kD on SDS-PAGE under reducing conditions. The optimal pH and temperature of the protease were 8.0 and 47 degrees C, respectively. In addition, this protease cleaved arginyl or lysyl residue containing substrates selectively and was only inhibited by aprotinin, FUT-175, and soy bean trypsin inhibitor and not by chymostatin, E-64 and iodoacetic acid. These results show that our purified serine protease belongs to the trypsin-type. Purified trypsin-like protease was shown to be allergenic by enzyme-linked immunosorbent assay. Antigenicity of trypsin-like protease was completely different from those of Der f I and Der f II. Both, 20 N-terminal amino acid sequence and amino acid compositions of the purified protease were very similar to those of Der f III. Good similarities were found between trypsin-like protease and Der f III concerning physicochemical properties such as molecular weight on SDS-PAGE and ammonium sulphate solubility. Summarizing the above data, it can be concluded that a trypsin-like protease from mite faecal extract is actually the Der f III allergen and that it may be involved in the digestive process of the mite as it was found not in mite body but in mite faeces.

Adolescent↗

PubMed1993

Single-photon emission computed tomographic investigation of patients with motor neuron disease.

To investigate the correlation between involvement of the CNS in motor neuron disease (MND) and neuroimaging abnormalities, we studied 18 patients with MND by single-photon emission computed tomography (SPECT) and MRI. Patients were divided into four groups according to the results of SPECT. Group 1 consisted of four patients with reduced isotope uptake in the frontal lobe, including the motor area, and in the anterior part of the temporal lobe; group 2 consisted of two patients with reduced isotope uptake in the motor area spreading to the adjacent frontal lobe; group 3 consisted of eight patients with reduced isotope uptake confined to the motor area; and group 4 consisted of four patients without reduced isotope uptake. We found dementia in group 1, borderline dementia in group 2, and no cognitive deficit in group 3 or four. MRI demonstrated enhanced T2-weighted signals along the pyramidal tract in eight patients, but this finding also existed in some control subjects. SPECT appears useful in identifying the location of cortical neuronal degeneration in patients with MND.

Aged↗

PubMed1993

T-cell infiltration and expression of MHC class II antigen by macrophages and microglia in a heterogeneous group in leukoencephalopathy.

We report here on T-cell infiltration and diffuse expression of the major histocompatibility complex (MHC) class II antigen in a heterogeneous group of macrophages and microglia in leukoencephalopathy (LE). Microglia reacting positively for HLA-DR were five times more numerous in LE than those in non-LE cases and were distributed densely in the degenerated white matter but sparsely in the subcortical arcuate fibers. CD4- and CD8-positive lymphocytes were 9 and 15 times more plentiful, respectively, in LE cases; they aggregated in the expanded Virchow-Robin spaces and frequently infiltrated the neural parenchyma. An intimate association of T cells with macrophages, and the expression of leukocyte function-associated antigen-1 (LFA-1) and intercellular adhesion molecule-1 (ICAM-1), accessory molecules in antigen presentation, were observed in each cell in the region of macrophage clusters. These results indicate that expression of MHC antigen is accompanied by cell adhesion molecules and by infiltration of T cells in a heterogeneous group in leukoencephalopathy and suggests their immunocompetence, although it may be secondary to destruction of myelin.

Aged↗

PubMed1993

Study of the antiseptic efficacy of a quick drying rubbing type povidone-iodine alcoholic disinfectant solution by the glove juice method.

The antiseptic efficacy of HAD Hand Wash (83% ethanol containing 0.5% povidone-iodine) was investigated by the glove-juice method in 29 cases amongst staff members of our university. The number of viable bacteria on the hands and fingers was counted three times, and the mean of these counts was used as the baseline value for each subject. The number of viable bacteria on both hands was the same prior to disinfection. After the hands were disinfected by rubbing with 3 ml of HAD Hand Wash until it dried, the subjects put on sterile gloves. The number of viable bacteria was counted on the right hand of all the subjects immediately after disinfection. The number of viable bacteria on the left hand was counted in 8 subjects 30 minutes after disinfection, and in 7 subjects each 1, 2 and 4 hours after disinfection. The bacteria were identified by subculture. The ratio of bacteria sterilized (bacterial reduction rate) was 75.4% immediately after disinfection, and 69.0%, 71.9%, 35.8% and 27.6% at 30 minutes, 1 hour, 2 hours and 4 hours, respectively. All of the bacteria detected were Gram-positive bacteria that were native to the sebaceous glands, sweat glands or skin surface; i.e. Staphylococcus, Micrococcus, Bacillus, and Streptococcus. The frequency of detection of Staphylococcus warneri was the highest before disinfection, followed by Staphylococcus epidermidis and Staphylococcus hominis, in that order. After disinfection, all these species showed a marked decrease in the number of bacteria. Micrococcus remained in half the subjects, while other species remained in less than one third of the subjects.

Antisepsis↗

PubMed1993

[Neuropathological study of autosomal dominant ataxia linked to loci on chromosome 6p (SCA 1)].

We reported an autopsy case of hereditary OPCA genetically proved to be SCA 1. Clinically, he showed cerebellar ataxia from beginning to the end stage, and was characterized by slow eye movement with external ophthalmoplegia, pyramidal tract signs, generalized amyotrophy including facial muscle, mild bulbar paresis, mild dementia, and urinary disturbance. Neuropathologically, the degeneration and loss of neurons with gliosis were seen in the Purkinje layer, dentate nucleus of the cerebellum, inferior Olive nucleus, motor nucleus of cranial nerve, anterior horn of the spinal cord, and column of the Clarke. And the myelinpallor was revealed in the connecting nerve fiber of these lesions, posterior column and spinocerebellar tract of the spinal cord.

Brain↗

PubMed1993

[Histological study in renal grafts--macrophages population in renal grafts].

We studied about the histological findings of the kidneys including of the infiltrated macrophages in one hour post-transplantation kidney biopsies (one hour biopsies) and re-biopsies on 11 patients. They were transplanted at 4-28 (ave. 15.1 +/- 3.8) years of age. The periods from transplantation to this study were 1.0-7.3 (ave. 3.3 +/- 1.9) years. 6 patients had acute rejections, and their renal function became normal after treatments. At this study, all grafts survived, and the patients had no abnormal findings except two (one had proteinuria, another had proteinuria and mild elevation of serum creatinine level). But histologically, five patients had chronic rejections among the 8 patients who had re-biopsies more than one year after transplantation. And we experienced 6 patients whose kidney had mesangial IgA deposits in one hour biopsies and 3 patients who had de novo type glomerulonephritis in re-biopsies (IgA neuropathy in 2 patients, membranous nephropathy in one). In one hour biopsies, the populations of macrophages in the interstitium were 4.18 +/- 2.84/mm2 in the patients who would have acute rejections (6 patients), 1.38 +/- 1.13/mm2 in the cases who would not have. It was suspected that the increase of the infiltrated macrophages in the interstitium in one hour biopsies could predict acute rejections. In re-biopsies, many macrophages infiltrated in the interstitium (8.34 +/- 4.86/mm2), particularly on patients who had chronic rejections.

Adolescent↗

PubMed1992

Electron microscopic investigation of the cerebral cortex after cerebral ischemia and reperfusion in the gerbil.

Prompt dendritic damage has been observed in the hippocampus of the gerbil brain after transient cerebral ischemia. In the present study, we studied the frontoparietal cortex of the gerbil brain electron microscopically after brief bilateral carotid occlusion to assess the vulnerability of dendritic processes. After ischemia for 5 min, there was swelling of the periphery of dendrites accompanied by swelling of mitochondria, cytoplasmic vacuolation and disintegration of microtubules in layer I, which spread to layer III after ischemia for 20 min. After reperfusion for 3-24 h following ischemia for 20 min, swelling in the periphery of dendrites and of mitochondria inside receded but vacuole formation and disintegration of microtubules propagated proximally. In neuronal perikarya, polyribosomal disaggregation was observed after ischemia for 20 min and persisted thereafter, while fragmentation of rough endoplasmic reticulum (ER) and microvacuolation occurred after reperfusion for 3 h. Electron-dense clumping of neuronal perikarya was observed after reperfusion for 6 h particularly in layers III and Vb, which increased in number for up to 72 h. The observed progressive damage in dendrites may be common to neurons vulnerable to cerebral ischemia and may significantly contribute to development of delayed neuronal death.

Animals↗

PubMed1992

Human peripheral blood lymphocytes express D5 dopamine receptor gene and transcribe the two pseudogenes.

Sequential reverse transcription and polymerase chain reaction (RT-PCR) of the mRNA were used to investigate the expression of dopamine receptors in human peripheral blood lymphocytes. The RT-PCR products contained three types of sequences, each corresponding to those of the D5 dopamine receptor gene and the two related pseudogenes. The lymphocyte cDNA library also contained the clones encoding parts of the three genes. Binding profiles of dopaminergic ligands to the lymphocytes were similar to those for the native neuronal membranes.

Benzazepines↗

PubMed1992

A novel mutant (transthyretin Ile-50) related to amyloid polyneuropathy. Single-strand conformation polymorphism as a new genetic marker.

DNA sequence polymorphisms in transthyretin (TTR) genes were investigated by single-strand conformation polymorphism (SSCP) analysis of polymerase chain reaction products. The amplified DNA fragments that encode each exon of the normal TTR gene showed two bands, representing the two complementary single strands of DNA. In one patient with amyloid polyneuropathy, the exon 3 DNA showed a unique, aberrant migration pattern. Direct sequencing analysis of the amplified exon 3 revealed a single base change (G-to-T), resulting in a novel amino acid substitution (Ser-50----Ile). We also present the SSCP patterns for five known Japanese TTR variants.

Amyloidosis↗

PubMed1992

Immunoelectron microscopic study of tubulin and microtubule-associated proteins after transient cerebral ischemia in gerbils.

Differential vulnerability of microtubule components to cerebral ischemia has been reported previously. We investigated the disintegration of microtubules using immunoelectron microscopy for alpha-tubulin and microtubule-associated protein 1A and 2 (MAP1A and 2). Mongolian gerbils were subjected to bilateral carotid occlusion for 10 to 30 min and reperfusion for up to 72 h following ischemia for 10 min. After ischemia for 10 min, some dendrites in the stratum moleculare of the subiculum-CA1 region lost immunoreaction products for alpha-tubulin and MAPs. Loss of the reaction products spread to the medial CA1 region during progressive ischemia for 30 min. In some dendrites, electron-dense precipitates for MAPs were dispersed in the dendritic cytoplasm with little reaction product on microtubules and without alteration of the reaction for alpha-tubulin. After recirculation, loss of electron-dense precipitates for alpha-tubulin and MAPs, as well as disintegration of microtubules, propagated further to the medial CA1 region and to the proximal dendrites. The present study demonstrated prompt disintegration of microtubules with rapid disappearance of the reaction for MAPs which seemed to be caused by detachment of MAPs from the microtubule cores.

Animals↗

PubMed1992

Intracerebral distribution of albumin after transient cerebral ischemia: light and electron microscopic immunocytochemical investigation.

The blood-brain barrier breaks down following cerebral ischemia, but the exact sequence of events for extravasation of serum proteins and their parenchymal distribution remain uncertain. We studied the distribution of serum albumin in the hippocampus of the gerbil brain using light and electron microscopic immunocytochemical techniques. With light microscopy, there was no reaction for albumin for the first 12 h after unilateral common carotid artery occlusion for 10 min and reperfusion. At 12 h, the reaction was weak and limited to the neuropil in the subiculum-CA1 region (between the subiculum and the medial CA1 region). After 24 h, the reaction became intense in the neuropil and neuronal perikarya in the subiculum-CA1 and medial CA1 regions. The electron microscopic immunocytochemical study of the subiculum-CA1 and medial CA1 regions revealed electron-dense immunoprecipitates in the extracellular space and the peripheral part of the apical dendrites as early as 30 min after reperfusion and in the astrocytic cytoplasm after reperfusion for 1 h. However, immunoprecipitates were not found in the neuronal perikarya until after reperfusion for 24 h. The present study demonstrated prompt appearance of albumin in the extracellular space of the brain parenchyma after re-establishment of cerebral circulation and prompt accumulation in the peripheral part of the dendrites with spreading to neuronal perikarya, likely in the process of degeneration and death.

Animals↗

PubMed1992

MRI findings of multiple sclerosis with acute transverse myelopathy.

We classified clinically definite multiple sclerosis (MS) patients who underwent brain MRI with superconductive magnet into 2 subgroups: group A, consisting of 14 patients who had shown acute transverse myelopathy (ATM) during the course of illness; and group B, 35 patients without ATM, and the same neuroradiologist, blinded to clinical profiles of the patients, investigated the MR scans. We analyzed some parameters such as distribution, size, shape and number of the lesions. Although the total number of lesions were similar in each group, and the number of small size or patchy shape solitary lesions were not different, the moderate, large, ovoid or confluent lesions were lower in number in group A, compared with group B. The degree of cerebral white matter lesions and periventricular lesions were higher in group B. Brainstem lesions were significantly less common in group A. These results show characteristic differences in MR-detected, possibly pathological, changes between these 2 groups, and support our previous report that group A may constitute a distinct subgroup in patients with MS.

Adult↗

PubMed1992

Familial amyloid polyneuropathy associated with the transthyretin Cys114 gene in a Japanese kindred.

A Japanese kindred with dominantly inherited amyloid polyneuropathy, commonly called familial amyloid polyneuropathy (FAP), has been identified. Amyloid protein was transthyretin (TTR) related and the patients were heterozygous for the mutant gene encoding TTR with a single amino acid substitution of cysteine for tyrosine at position 114. This family originated in Nagasaki Prefecture, Japan, and 12 of the 36 known members of six generations have been affected. The initial symptoms occurred in their thirties with the cardinal features of polyneuropathy, vitreous opacities and cardiac disease. Sensory neuropathy was severe in the lower limbs. Autonomic disturbances, especially postural hypotension, were the most debilitating to the patients. Amyloid deposits were detected widely in most organs except for the central nervous system. The duration from the onset of the disease to death was within 10 yrs. Heart failure caused by heavy amyloid deposits was the most common cause of sudden death.

Adult↗

PubMed1992

Two children with bromate intoxication due to ingestion of the second preparation for permanent hair waving.

We report two children who suffered from sodium bromate intoxication due to ingestion of the second preparation for permanent hair waving (the second permanent preparation). One child suffered from gastrointestinal symptoms only. The other exhibited slight acute renal insufficiency. Results of the histological examination of the kidney in the sick child with acute renal insufficiency showed sporadic epithelial separation of the proximal tubuli under light microscopy. In addition, we could demonstrate more clearly epithelial separation and unbroken tubular basement membranes under electron microscopy (EM). To our knowledge, this is the first report of EM findings in this disease. The mechanism of epithelial injuries by bromate is not clear.

Acute Kidney Injury↗

PubMed1992

HLA profiles of multiple sclerosis in Hokkaido, the northernmost island of Japan.

We studied HLA haplotypes in 43 consecutive clinically definite MS patients in Hokkaido. The patients were classified into Group A, 12 patients with acute transverse myelopathy (ATM) during the course of illness, and Group B, 31 without ATM. We found an association with HLA-DQw7 in Group A, and with DR4 and DRw8 in Group B. The frequency of DQw7 and DR4 were significantly different between Groups A and B. This study may indicate the different genetic backgrounds between the groups. DRw8 and DRw52 antigens were significantly more common in MS than in controls. Our result is inconsistent with previous Japanese studies, and ethnic variation might be considered as a possible cause of the contradiction.

Adult↗

PubMed1992

[Susceptibility of RD-9H8 cells derived from RD cells to enteroviruses and its application for measuring neutralizing antibodies against coxsackievirus group B].

We carried out cloning of RD cells and obtained cloned cell line RD-9H8, which is highly sensitive to enteroviruses. Cytopathic effect (CPE) of RD-9H8 cells was more remarkable than that of original RD cells. The RD-9H8 cells were used to measure the neutralizing antibodies to coxsackievirus group B in sera from 93 medical students collected in Oct. 1990 at Iwate Medical University. The proportions of confirmed positive sera were coxsackievirus type B1 44.1%, type B2 50.5%, type B3 46.2%, type B4 64.5%, type B5 53.8% and type B6 4.4%.

Antibodies, Viral↗

PubMed1992

A single MEF-2 site is a major positive regulatory element required for transcription of the muscle-specific subunit of the human phosphoglycerate mutase gene in skeletal and cardiac muscle cells.

In order to analyze the transcriptional regulation of the muscle-specific subunit of the human phosphoglycerate mutase (PGAM-M) gene, chimeric genes composed of the upstream region of the PGAM-M gene and the bacterial chloramphenicol acetyltransferase (CAT) gene were constructed and transfected into C2C12 skeletal myocytes, primary cultured cardiac muscle cells, and C3H10T1/2 fibroblasts. The expression of chimeric reporter genes was restricted in skeletal and cardiac muscle cells. In C2C12 myotubes and primary cultured cardiac muscle cells, the segment between nucleotides -165 and +41 relative to the transcription initiation site was sufficient to confer maximal CAT activity. This region contains two E boxes and one MEF-2 motif. Deletion and substitution mutation analysis showed that a single MEF-2 motif but not the E boxes had a substantial effect on skeletal and cardiac muscle-specific enhancer activity and that the cardiac muscle-specific negative regulatory region was located between nucleotides -505 and -165. When the PGAM-M gene constructs were cotransfected with MyoD into C3H10T1/2, the profile of CAT activity was similar to that observed in C2C12 myotubes. Gel mobility shift analysis revealed that when the nuclear extracts from skeletal and cardiac muscle cells were used, the PGAM-M MEF-2 site generated the specific band that was inhibited by unlabeled PGAM-M MEF-2 and muscle creatine kinase MEF-2 oligomers but not by a mutant PGAM-M MEF-2 oligomer. These observations define the PGAM-M enhancer as the only cardiac- and skeletal-muscle-specific enhancer characterized thus far that is mainly activated through MEF-2.

Animals↗