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S Tsuji

Publications and source records attributed to S Tsuji.

At least 901 records · Page 50Linked to original sources
PubMed1986

Quantitative cerebral blood flow measurements using N-isopropyl-(iodine 123) p-iodoamphetamine and single photon emission computed tomography with rotating gamma camera.

Sixty regional cerebral blood flow measurements were performed on 4 normal volunteers, 7 epileptics, and 40 cerebrovascular disorders using intravenously injected N-isopropyl-(I-123)p-iodoamphetamine (123I-IMP) and single photon emission computed tomography with rotating gamma camera. Arterial blood sampling was combined for obtaining absolute blood flow values. The brain activity distributions of the tomographic image from 30 min after injection, when brain activity reached a plateau, were corrected to represent 5-min reference values with the use of the monitored entire brain's time-activity curve. Brain mean blood flow values ranged from 54 to 63, 34 to 59, and 20 to 60 ml/100 g/min, in normal volunteers, epileptics, and subjects with cerebrovascular disorders, respectively. Brain mean 123I-IMP uptake corrected for injection dose did not correlate with these absolute flow values. This quantitative method is especially useful for diagnosing diffuse flow reductions, which were observed in 8 (14%) of 56 studies in the patients.

Adolescent↗
PubMed1986

Framework of the enteric nerve plexuses: an immunocytochemical study in the guinea pig jejunum using an antiserum to S-100 protein.

Immunostained sections and whole-mount preparations of the layers of the guinea pig jejunum were investigated by an improved peroxidase-antiperoxidase method using an antiserum to S-100 protein. A delicate latticework of S-100 protein immunopositive glial cells was demonstrated extending in the longitudinal muscle layer, myenteric or Auerbach's plexus, circular muscle layer including the deep muscular plexus, submucous layer including the submucous or Meissner's plexus, lamina muscularis mucosae and lamina propria mucosae. The whole enteric nerve plexuses consisted of two subsystems; nerve plexuses of the muscular coat and those of the submucous and mucous coats. These two subsystems were joined to each other by thick, connecting branches perforating the inner circular muscle layer. Extrinsic nerves entering the myenteric plexus formed a specialized junctional structure containing S-100 protein immunopositive glial cells, whereas those entering the submucous plexus ran along the submucous arteries. We proposed the term enteroglial cells to designate the S-100 protein immunopositive cells which ensheathed the somata and processes of the enteric neurons. The frameworks of all structures in the enteric nerve plexuses from the largest ganglia to the thinnest nerve fasciculi were constructed of these enteroglial cells. A spectrum of the enteroglial cells was presented. Those in the myenteric and submucous ganglia were found similar to the astroglia of the central nervous system and to the satellite cells in the peripheral ganglia. Those in the primary and secondary fasciculi of the myenteric plexus formed a kind of neuropil together with the neuronal processes. Those in the tertiary fasciculi of the muscular coat formed the framework of the autonomic ground plexus. We tentatively concluded that the interstitial cells of Cajal contain an immunoreactivity for S-100 protein, and thus are glial in nature. The occurrence of specialized enteroglial cells with a neuron-like function was discussed in the autonomic ground plexus of the muscular coat. In the lamina propria mucosae, there was a fine latticework of the S-100 protein immunopositive enteroglial cells. This latticework corresponded to that of the interstitial cells of Cajal in the villous and periglandular plexuses.

Animals↗
PubMed1986

Retrovirus-mediated transfer of the human glucocerebrosidase gene to Gaucher fibroblasts.

A recombinant retrovirus carrying complementary DNA containing the complete coding sequence for human glucocerebrosidase was constructed and used to infect mouse cells and human fibroblasts from a type 2 Gaucher patient. The cDNA stably integrated in the genome of the recipient cell. Infected cells made glucocerebrosidase-cross-reacting material, and the protein was glycosylated and contained the epitope(s) missing in the type 2 mutant glucocerebrosidase. This study demonstrates the feasibility of efficiently transferring the gene encoding glucocerebrosidase to Gaucher cells using retrovirus as vector.

Animals↗
PubMed1985

Ganglio-N-tetraosylceramide (asialo GM1), an antigen common to the brain and immune system: its localization in myelin.

Anti-brain antisera are known to contain several interesting antibodies showing immunological cross-reactions between the nervous and hematopoietic systems, suggesting the existence of antigens common to the two systems (common antigens). One of these is the glycosphingolipid asialo GM1 (ganglio-N-tetraosylceramide, GgOse4Cer), but its location in the nervous system is unknown. Therefore, the location of the brain antigen that reacts with anti-asialo GM1 antibody was examined. On immunohistochemical treatment of sections of mouse brain with purified anti-asialo GM1 IgG, the white matter was stained specifically. Because myelin is a major component of the white matter, neutral glycosphingolipids were prepared from the myelin fraction. On thin-layer chromatography, myelin glycosphingolipids gave a band with the same mobility as asialo GM1. This band was also stained immunochemically by the peroxidase anti-peroxidase procedure using anti-asialo GM1 IgG. The glycosphingolipid of this band gave the molar ratio of sugars expected for asialo GM1. From these results it was concluded that the glycosphingolipid asialo GM1 exists in myelin.

Animals↗
PubMed1985

Unconventional pathogens causing spongiform encephalopathies absent in blood products.

To determine whether unconventional pathogens causing subacute spongiform encephalopathy may be present in blood products, a newly developed hepatitis B vaccine and a widely used blood product were injected into mice and rats. As only a few aged mice in the test and the control groups showed spongiform encephalopathic change of a sparse or mild degree and which differed from that seen in rodents infected with Creutzfeldt-Jakob disease, the presence of unconventional pathogens in the tested inocula can be ruled out.

Animals↗
PubMed1985

Ultracytochemical localization of acetylcholine-like cations in excited motor end-plates by means of ionic fixation.

Using rapid ionic fixation with molybdic or tungstic heteropolyanions (strong precipitating agents of quaternary ammonium cations such as choline and acetylcholine), acetylcholine-like cations were localized as point-like precipitates in the synaptic vesicles of resting (electrically nonstimulated) motor nerve terminals. When performed at low temperature, the same procedure revealed spot-like precipitates (presumed to be exocytotically released acetylcholine-like cations) in the synaptic cleft in the vicinity of the active zone. These precipitates were often seen in paired forms. Unlike resting motor-nerve terminals, excited terminals (electrical stimulation with occasional 4-aminopyridine pretreatment) after ionic fixation exhibited, at first, laminar precipitates both in the vicinity of the active zone inside the nerve terminals and in the synaptic space. In the vicinity of the active zone, the laminar precipitates were directed towards the synaptic membrane, while those in the synaptic space showed no orientation. Ionic fixation also revealed diffused precipitates both around the synaptic vesicles and on the axoplasmic side of the presynaptic membrane. Finally, the same fixation procedure demonstrated the presence of empty synaptic vesicles (without point-like precipitates) in close contact with the presynaptic membrane. The laminar and diffused precipitates are presumed to be two different forms of the same salts of acetylcholine-like cations that are insolubilized by ionic fixation in both the nerve terminals and the synaptic space of excited motor end-plates.

4-Aminopyridine↗
PubMed1985

Metabolism of [17,18-3H2]hexacosanoic acid and [15,16-3H2]lignoceric acid in cultured skin fibroblasts from patients with adrenoleukodystrophy (ALD) and adrenomyeloneuropathy (AMN).

We have studied the metabolism of [17,18-3H2]hexacosanoic acid and [15,16-3H2]lignoceric acid in cultured skin fibroblasts from patients with adrenoleukodystrophy (ALD) and adrenomyeloneuropathy (AMN). The successful solubilization of the very long chain fatty acids as albumin conjugates was confirmed by analysis using glycerol density gradient centrifugation. The composition of radioactive fatty acids in total lipids of fibroblasts after culture for 7 days in the presence of [17,18-3H2] hexacosanoic acid or [15,16-3H2]lignoceric acid was analyzed by radio-gas chromatography. Most of the fatty acids added to the culture media were degraded to shorter-chain fatty acids both by control, and ALD or AMN fibroblasts. However, the content of the remaining radioactive hexacosanoic acid or lignoceric acid was much higher in ALD or AMN fibroblasts, and the content of radioactive shorter-chain fatty acids was much lower in ALD or AMN fibroblasts. These results indicate that the degradation of very long chain fatty acids is decreased in ALD, but also that there is a substantial amount of residual activity of their degradation in ALD fibroblasts.

Adrenoleukodystrophy↗
PubMed1985

Evidence on hypomyelination of central nervous system in murine muscular dystrophy.

To elucidate the disturbances of myelin metabolism in the nerve tissue of murine muscular dystrophy, the lipid composition of and the developmental changes in 2', 3'-cyclic nucleotide 3'-phosphohydrolase (CNPase) and cholesterol ester hydrolase (CEHase) activities in the purified CNS myelin of dystrophic mice were determined. Several kinds of lipids, total galactolipid and cerebroside sulfatide levels were significantly reduced as compared with controls. Total cholesterol levels in the spinal cord of dystrophic mice were moderately higher. CEHase and, to a lesser degree, CNPase activities were reduced in the purified myelin of the CNS of the dystrophic mice. The reduced myelin CEHase activity in dystrophic mice suggests that impairment of hydrolysis of steryl esters may be important in the development of hypomyelination of the CNS.

2',3'-Cyclic Nucleotide 3'-Phosphodiesterase↗
PubMed1985

Gene mapping and leader polypeptide sequence of human glucocerebrosidase: implications for Gaucher disease.

Analysis of immunologic cross-reacting material in Chinese hamster-human somatic cell hybrids allowed assignment of the structural gene for glucocerebrosidase (glucosylceramidase; beta-D-glucosyl-N-acylsphingosine glucohydrolase, EC 3.2.1.45) to chromosome 1 bands q21-q32. In situ hybridization of a radiolabeled human glucocerebrosidase cDNA to high resolution human chromosomes demonstrated that a single locus encoding glucocerebrosidase is on 1q21, adjacent to a region of chromosome 1 (1qh) abundant in structural heteromorphisms. We also have identified a hydrophobic leader polypeptide encoded by this locus, permitting a more complete description of the biosynthesis of the enzyme. These results suggest that the type-specific protein polymorphisms in Gaucher disease result from mutations at this single locus, whose segregation might be followed by linkage to visible chromosomal heteromorphisms.

Animals↗
PubMed1985

Bioactive gangliosides. IV. Ganglioside GQ1b/Ca2+ dependent protein kinase activity exists in the plasma membrane fraction of neuroblastoma cell line, GOTO.

A ganglioside-stimulated protein phosphorylation system was discovered in plasma membrane fractions of human neuroblastoma cells (GOTO). Gangliosides (GQ1b, GT1a, GT1b, GD1a, GD1b, GD3, and GM1) could stimulate this system. GQ1b showed the most effective stimulation among these gangliosides. The substrate specificity was rather broad. Not only some (de novo) proteins of the membranes but also purified histones and tubulin were phosphate-acceptable. This protein phosphorylation system specifically depended upon Ca2+ (optimum concentration: 50-100 microM). The optimum pH was 7.0-7.5. GQ1b/Ca2+ could not directly activate well known protein kinases (Ca2+/phospholipid-activated protein kinase, Ca2+/calmodulin-activated protein kinase, and cyclic nucleotide-dependent protein kinases). Furthermore, GQ1b could replace neither phospholipids nor calmodulin. Thus, an unknown, new type of protein kinase(s) may be involved in this system. Alternatively, GQ1b may activate some known protein kinase(s) in cooperation with another unknown factor which may be removed during the preparation of the partially purified known protein kinase used in this experiment.

Animals↗