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Biomedical subjects

Y Inoue

Publications and source records attributed to Y Inoue.

At least 1,603 records · Page 89Linked to original sources
PubMed1988

MR imaging of intraspinal tumors--capability in histological differentiation and compartmentalization of extramedullary tumors.

Magnetic resonance (MR) images of 29 consecutive patients with intraspinal neoplasms (9 intramedullary tumors, 20 extramedullary tumors) were reviewed to evaluate the utility of MR imaging in distinguishing the intraspinal compartmental localisation and signal characteristics of each lesion. Compartment and histology of all neoplasms were surgically proven. MR correctly assigned one of three compartments to all lesions, 9 intramedullary, 14 intradural extramedullary (6 schwannomas, 3 neurofibromas, 5 meningiomas), and 6 extradural (3 schwannomas, 1 meningioma, 1 cavernous hemangioma, 1 metastatic renal cell carcinoma). All intramedullary tumors showed swelling of the spinal cord itself. In all five extradural tumors a low intensity band was visualized between the spinal cord and tumor. On the other hand, a low intensity band was demonstrated in no cases with intradural tumors. Visualization of this low intensity band is important in differentiating extradural from intradural-extramedullary lesions. We call this low intensity band, "the extradural sign". Signal intensity of intradural tumors varied with histology. In extramedullary tumors, signal intensity of schwannomas was similar to that of the cerebrospinal fluid (CSF) both on T1 weighted (inversion recovery) and T2 weighted spin echo (SE) images. On the other hand, meningiomas tended to be isointense to the spinal cord on both T1 and T2 weighted SE images. We found relatively reliable signal characteristics to discriminate meningioma from schwannoma.

Astrocytoma↗
PubMed1988

MR appearance of Rathke's cleft cysts.

Two of three patients who proved to have symptomatic Rathke's cleft cysts presented with visual field deficit and all with diabetes insipidus. CT showed intra- and suprasellar cystic low density lesions with ring enhancement. MR showed intra- and suprasellar masses. On the T1-weighted images two of the three had hyperintense portions similar to fat and the other a hyperintense portion similar to white matter within the cysts. These portions were isointense to brain on the T2-weighted images in all cases. This characteristic intensity on MR images provides differentiation from cystic pituitary adenomas and cystic craniopharyngiomas, and leads to correct diagnosis of Rathke's cleft cyst.

Adult↗
PubMed1988

Magnetic resonance images of tuberous sclerosis. Further observations and clinical correlations.

The cerebral lesions in tuberous sclerosis are of three kinds: subependymal nodules, cortical tubers, and cluster of heterotopic cells in the white matter. Understanding of these hamartomas is still incomplete even with modern imaging modalities. Magnetic resonance (MR) images of ten patients with tuberous sclerosis were reviewed and compared to computed tomographic (CT) scans and to the clinical severity of the disease. T2 weighted spin echo (TR = 1800, TE = 120) images and inversion recovery (TR = 2100, TI = 500-600, TE = 40) images were obtained at the same axial planes. Periventricular nodules were better seen, because of their calcifications, with CT than with MR imaging. They were demonstrated as iso- to low intensity depending on the amount of calcification on T2 weighted images, and as a similar intensity to the white matter on IR images. Small peripheral lesions in the hemispheres, which were only occasionally seen as small low density areas on CT scans, were well demonstrated on MR images. These foci were hyperintense on T2 weighted images, and hypointense on IR images. Exact location of these was not in the cortex, but in the subcortical white matter. The findings indicate that these foci represent the pathologically well known demyelinating foci, which are commonly present under the cortical tuber, but may be independent of them. Cortical tubers were not confidently identified, which suggested that they might have similar intensity to the cortical gray matter.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1988

A case of Vibrio vulnificus infection.

Vibrio vulnificus, a recently described strain of the halophilic Vibrio species, was isolated from the blood of a 73-year-old man, who developed rapidly progressive wound infection and fatal septicemia. Twenty-one patients with Vibrio vulnificus infection have been reported in the Japanese literature. Vibrio vulnificus most frequently causes primary septicemia and necrotising cellulitis after the eating of raw fish or shellfish or after exposure to seawater. The infection is characterized by its occurring during the warm months of the year, in patients with underlying diseases, especially liver diseases, and the mortality rate is surprisingly high. Clinicians should therefore consider the possibility of Vibrio vulnificus infection in the differential diagnosis of severe wound infections. Early surgical intervention and intensive antibiotic therapy are recommended for preventing the progress of the septicemia.

Aged↗
PubMed1988

Abnormal S-state turnovers in NH3-binding Mn centers of photosynthetic O2 evolving system.

The inhibitory effects of NH3 on S-state turnovers were studied by curve fitting and deconvolution of thermoluminescence glow curves and low-temperature EPR spectroscopy. The following results were found: (i) High concentrations of NH3 upshifted the recombination temperatures of both S2QB- and S2QA- charge pairs, indicating formation of an abnormal S2 state having a lowered oxidation potential. (ii) The abnormal S2 was correlated to alterations in EPR multiline signal: high concentrations of NH3 induced the modified multiline signal having reduced hyperfine line spacing, accompanied by disappearance of the g = 4.1 signal, while low concentrations of NH3 reduced the line width of the g = 4.1 signal with a slight shift in its g value to 4.2 concomitant with suppression in amplitude of the normal multiline signal, both suggesting coordination of NH3 to the Mn center. (iii) More than half of the NH3-binding abnormal S2 centers underwent S-state turnover to yield S3QB- and S3QA- pairs having normal thermoluminever, the NH3-binding S3 was unable to undergo further S-state turnovers. (iv) The interruption of S-state turnover at S3 was assumed to be due to the inability of electron abstraction from the S3 state. Based on these, the mechanism of NH3 inhibition was discussed.

Ammonia↗
PubMed1988

Zellweger-like syndrome with detectable hepatic peroxisomes: a variant form of peroxisomal disorder.

A male infant with typical clinical and biochemical findings of Zellweger syndrome, but in whom hepatic peroxisomes were detected by electron microscopy, had profound hypotonia, hepatomegaly, typical facial appearance including large fontanelle and frontal bossing, convulsions, panaminoaciduria, and hyperammonemia. He died of liver failure at age 5 months. There were increased levels of very long chain fatty acids and trihydroxycoprostanic acid in serum, and increased excretion of dicarboxylic acids and tyrosine metabolites in the urine. Levels of peroxisomal enzymes, acyl coenzyme A oxidase, bifunctional protein, 3-ketoacyl coenzyme A thiolase, and dihydroxyacetone phosphate acyltransferase in the liver tissue from the patient were all deficient, findings consistent with Zellweger syndrome. However, immunocytochemical study and electron microscopic examination of the liver at autopsy revealed that hepatic peroxisomes were present at a level similar to that in a control subject. These observations suggest further heterogeneity in Zellweger syndrome and a different pathogenesis in this variant case.

Bile Acids and Salts↗
PubMed1988

Purification and characterization of NADP+-dependent 3 alpha-hydroxysteroid dehydrogenase from mouse liver cytosol.

A monomeric 3 alpha-hydroxysteroid dehydrogenase with a molecular weight of 34,000 was purified to apparent homogeneity from mouse liver cytosol. The enzyme catalyzed the reversible oxidation of the 3 alpha-hydroxy group of C19-, C21-, and C24-steroids, reduced a variety of carbonyl compounds, and was inhibited by SH-reagents, synthetic estrogens, anti-inflammatory drugs, prostaglandins, and delta 4-3-ketosteroids. Although these properties are similar to those of the enzyme from rat liver cytosol, the mouse enzyme exhibited low dehydrogenase activity toward benzene dihydrodiol and some alicyclic alcohols, it showed a strict cofactor specificity for NADP(H), and high substrate inhibition was observed in the reverse reaction. In addition, dexamethasone, deoxycorticosterone, and medroxyprogesterone acetate inhibited the mouse enzyme competitively at low concentrations and noncompetitively at high concentrations, whereas hexestrol, indomethacin, and prostaglandin A1 were competitive inhibitors. Steady-state kinetic measurements in both directions indicated that the reaction proceeds through an ordered bi bi mechanism with the cofactors binding to the free enzyme. The 3-ketosteroid substrates inhibited the enzyme uncompetitively at elevated concentrations, suggesting that the substrates bind to the enzyme.NADPH complex and to the enzyme NADP+ complex.

3-Hydroxysteroid Dehydrogenases↗
PubMed1988

Local similarity in the amino acid sequence between the non-catalytic region of Rous sarcoma virus oncogene product p60v-src and intermediate filament proteins.

We found local sequence-similarity between the non-catalytic region of the Rous sarcoma virus oncogene product, p60v-src, and the core region of cytoskeletal keratin through an extensive similarity search of segments of proteins. The segments showing similarity in p60v-src were in the region that is important for morphological transformation, and corresponded to segments with unique structural features predicted for intermediate filament proteins. We suggest that cellular components related with intermediate filament proteins or the sequence shared by the two proteins may be involved in the regulation of the kinase activity or substrate specificity of p60v-src.

Amino Acid Sequence↗
PubMed1988

Effect of activation of the Epstein-Barr virus genome on expression of B cell differentiation antigens of Burkitt's lymphoma lines.

Using anti-human B cell monoclonal antibodies prepared against B1 (CD20), B2 (CD21), B4 (CD19), and BB-1 (B lymphoblast antigen-1), we compared the expression of B cell differentiation antigens on a Jijoye-P3HR-1 cell line family of Burkitt's lymphomas. The expression of BB-1 and B2 antigens was faint on P3HR-1 K cell line which is an Epstein-Barr virus (EBV) high producer. On the other hand, B1 and B4 antigens were strongly expressed on it. It was also found that BB-1 expression decreased on P3HR-1 cells after activation of intracellular EBV genes by treating chemically with tumor-promoting agent (TPA) and n-butyrate, or on Raji cells on superinfection with EBV. This decrease of BB-1 was blocked by the additional treatment with retinoic acid, an inhibitor of virus replication. Dual immunofluorescence staining analysis showed that the individual cell expressing EBV-associated antigens expressed BB-1 antigen only marginally. The relationship between the change in phenotypes of host B cells and the activation of the EBV genome is discussed.

Antigens, Differentiation, B-Lymphocyte↗
PubMed1988

Developmental and regional changes of mRNA for a cerebellar protein (spot 35) in the rat brain.

Spot 35 protein is a cerebellar Ca-binding protein. Because Southern blot analysis showed evidence for the nucleotide sequence of spot 35 protein cDNA in the rat genome, we applied cDNA to quantitate the mRNA of rat spot 35 protein. The size of this mRNA was about 1,900 nucleotides in length, and that of mRNA from bovine cerebellum was larger. We also examined the developmental changes and regional distribution of spot 35 protein mRNA in rat brains by dot-blot analysis using cDNA as a probe. During postnatal days 1-20, a rapid increase of mRNA levels was observed. Further, the level of mRNA for spot 35 protein was found in the cerebellum and was negligible in the cerebral cortex, striatum, and hippocampus.

Animals↗
PubMed1988

The interaction of cations with activity of soluble protein kinase C from mouse brain.

The interaction of some cations with the enzymatic activity of soluble protein kinase C was determined in order to elucidate whether protein kinase C can be activated by other metal cations besides Ca2+. Protein kinase C was activated by Ca2+ and Sr2+ having EC50 values of nearly 10 microM and 200 microM, respectively. Ba2+ likewise activated protein kinase C but was less potent. Co2+, Ni2+ and Mn2+ had no activating effects on the activity in the absence of Ca2+, but was slightly reduced in the presence of Ca2+ (0.5 mM). Cations with ionic radii close to Ca2+ (0.99 A) inhibited the activity irrespective of the absence or presence of Ca2+. The order of potency is as follows: Hg2+ greater than Cd2+ approximately Cu2+ much greater than Sm3+ greater than Tb3+ greater than La3+. Pb2+ and Zn2+, which showed a high affinity to SH-groups, as well as Hg2+, Cd2+ and Cu2+, which also inhibited the activity. Thus, among the ions investigated, the alkaline-earth ions Sr2+ and Ba2+ could be substituted for Ca2+, irrespective of ionic radii. The serious environmental pollutants such as Hg2+, Cd2+ or Pb2+ impaired the activity of protein kinase C probably due to SH-blocking.

Animals↗
PubMed1988

Action of mercurials on activity of partially purified soluble protein kinase C from mice brain.

The enzymatic activity of soluble protein kinase C from mice brain was inhibited by mercuric chloride (II) (HgCl2) and organic mercurials, i.e. methyl mercury, phenyl mercury and p-chloromercuribenzoic acid (PCMB). The IC50 was 0.08 microM for HgCl2 and about 1 microM for organic mercurials. Sulfhydryl blocking reagents such as 5,5'-dithiobis-2-nitrobenzoic acid (DTNB) and N-ethylmaleimide (NEM) were less potent but nevertheless inhibited the enzymic activity of protein kinase C. The Hill coefficients of HgCl2, DTNB and NEM were close to unity whereas the values for organic mercurials were 1.3 to 1.5. The inhibition was of a non-competitive type with respect to H1 histone. 3H-PDBu binding activity was also inhibited by all of the reagents in a non-competitive manner. Mercurials apparently bind to sulfhydryl groups of protein kinase C to inhibit the enzymatic activity.

Animals↗
PubMed1988

Changes in plasma glucagon, pancreatic polypeptide and insulin during development of alloxan diabetes mellitus in dog.

Changes in canine plasma glucose, immunoreactive glucagon (IRG), pancreatic polypeptide (PP) and insulin (IRI) were studied during the acute development of diabetes mellitus after iv alloxan injection. 100 mg or 75 mg/kg body weight of alloxan was injected iv and blood was taken successively till one or two days later. Plasma glucose showed four phases: first immediate and moderate decrease appeared 30 min after injection, second initial hyperglycemic phase, third hypoglycemic and fourth diabetic ones. Plasma IRI had already increased to 182 +/- 60 microU/ml 10 min after injection and again began to increase after about 6 h, peaking to 134 +/- 49 microU/ml at 18 h. Plasma IRG began increasing gradually soon after alloxan injection. The initial value was 196 +/- 26 pg/ml and it increased to 534 +/- 144 pg/ml at 4 h during the initial hyperglycemic phase, then reached a higher level through the hypoglycemic and diabetic phases. The change in plasma PP was similar to that in IRG. The initial value was 256 +/- 95 pg/ml at 12 h after injection, peaking to 840 +/- 100 pg/ml in the hypoglycemic phase. Similar blunted values were obtained following 75 mg/kg alloxan injection. Thus not only plasma IRI but also plasma IRG and PP varied greatly during the acute development of alloxan diabetes and some contribution of IRG to the initial hyperglycemic phase was suggested.

Animals↗
PubMed1988

Tumors and tumor-like conditions of the middle ear and mastoid: role of CT and MRI. An analysis of 100 cases.

CT and MRI scanning provide valuable information in determining location and extension of middle ear and mastoid tumors and tumor-like conditions. The bone anatomy depicted by CT better delineates the involvement of the middle ear diseases. In glomus tumors, facial nerve tumors, and other cases including temporal bone metastases, the combination of CT and MR imaging is exceedingly useful in the diagnosis and management of patients.

Cranial Nerve Neoplasms↗