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Biomedical subjects

E Sato

Publications and source records attributed to E Sato.

At least 397 records · Page 22Linked to original sources
PubMed1987

Preferential expression of glycolipids reacting with Ricinus communis agglutinin-I in human colorectal adenocarcinomas.

Tumor-associated glycosphingolipids expressed on human colorectal adenocarcinomas were surveyed by staining of glycolipid bands on thin layer chromatogram with several horse radish peroxidase-labeled lectins. Glycolipids reacting with Ricinus communis agglutinin-I were found in all of the tumors from 9 patients with various types of colorectal adenocarcinomas, but only very weakly in the normal mucosa. Susceptibility to glycosidases and chromatographic mobilities indicated that these glycolipids were lactosylceramide, paragloboside and probably higher homologues of neolactoseries glycolipids.

Adenocarcinoma↗
PubMed1986

Calcium-dependent association of 33 kDa protein in polymorphonuclear leukocytes with phospholipid liposomes containing phosphatidylserine or cardiolipin.

The effects of lipids and Ca2+ on the association of cytoplasmic proteins of polymorphonuclear leukocytes (PMN) with dipalmitoylphosphatidylcholine liposomes containing phosphatidylserine (PS) or cardiolipin (CL) were examined. In the presence of Ca2+, a cytoplasmic protein (33 kDa) of PMN was found to be a major component that bound to these liposome membranes. The maximum association with the liposomes was obtained at the molecular concentration of 25% CL and 50% PS; the required concentrations of Ca2+ were in the nanomolar and micromolar ranges for CL and PS, respectively. The liposome-associated 33 kDa protein was released from liposomes by an addition of EGTA. These results suggest that the 33 kDa protein reversibly associates to the cytoplasmic surface of PMN plasma membranes where PS localizes depending on a small change in intracellular concentration of free Ca2+.

Animals↗
PubMed1986

Polyamine binding sites on Escherichia coli ribosomes.

To determine the binding sites of polyamines on Escherichia coli ribosomes, ribosomal proteins crosslinked with polyamines through bifunctional reagents were analyzed. When 1,5-difluoro-2,4-dinitrobenzene was used as a crosslinking reagent, spermine was bound to S3, S8, S9, L1, L2, L3, L5, L6, L13, L18, L24, and L27 proteins. When dimethyl suberimidate was used, spermine was bound to S1, S3, S4, S5, S7, S8, S9, S15, L1, L2, L3, L6, L18, and L24 proteins. In addition to crosslinking with the above proteins, spermidine, when crosslinked with dimethyl suberimidate, bound to S2, S14, S20, L4, L5, L9, L13, and L16 proteins. The relationship between the binding site(s) of polyamines on ribosomes and the function of polyamines is discussed.

Bacterial Proteins↗
PubMed1986

Differential distribution of receptors for two fucose-binding lectins in embryos and adult tissues of the mouse.

Ulex europaeus agglutinin-I (UEA-I) recognizes the Fuc alpha 1----2 Gal linkage. Receptors for UEA-I were not detected in mouse embryos until the 13th day of embryo-genesis, except for their temporary expression in early trophectoderm cells. In adult mice, UEA-I receptors were detected at various sites, including cells of the digestive tracts, the bronchial epithelium, Hassall's corpuscle of the thymus, and the skin. The fucose-binding protein of Lotus tetragonolobus (FBP) is another lectin that recognizes fucosyl residues. The distribution of FBP receptors was significantly different from that of UEA-I receptors. FBP receptors were first detected in late 8-cell embryos and were expressed in the embryonic ectoderm, visceral endoderm, and trophoblastic giant cells in egg-cylinders. At later stages, the distribution of FBP receptors became restricted to certain parts of the embryo. In the adult, the distribution of FBP receptors was more restricted than that of UEA-I receptors. Particularly in embryos before the 11th day of gestation, the distribution of FBP receptors resembled that of SSEA-1, which is defined by the Gal beta 1----4(Fuc alpha 1----3) GlcNAc linkage. From the specificity of FBP, we inferred that the disappearance of SSEA-1 and FBP receptors during embryogenesis is not the result of alpha 1----2 fucosylation of the terminal galactosyl residue in the determinant. The fact that the expression of two fucose-related cell-surface markers, i.e., UEA-I receptors and SSEA-1 (or FBP receptors), is developmentally regulated in an entirely different fashion is an excellent example illustrating the precise control of differentiation-dependent alterations in cell-surface carbohydrates.

Aging↗
PubMed1986

Microphotometric analysis of Hodgkin's disease in comparison with adult T cell lymphoma.

In order to achieve a clear distinction between Hodgkin's disease (HD) and peripheral T cell lymphomas, a microphotometric analysis was made on 5 micron thick sections, by illustrating a nuclear density scattergram (NDS) and a superimposed DNA histogram (S-DNA H) which was composed of cell populations by nuclear size versus DNA content. HD cells (including mononuclear cells, Reed-Sternberg's cells, and lacunar cells) showed the oblique zonal cluster (OZC) on the NDS, indicating their proliferative ability. In particular, the small HD cells in lymphocytic depletion (LD) meant their high proliferation. The lymphocytes among HD cells showed an euploid diploid pattern. The HD cells of the borderline cases, having lymphocytes with twisted or distorted nuclei, proliferated with higher and wider ploidy than the HD cells in LD. The population of HD cells in the borderline cases was much larger than that of the HD cell-like cells in adult T cell lymphoma (ATL), pleomorphic type. The distorted lymphocytes fall in the euploid diploid range and had smaller nuclei than the medium-sized neoplastic T cells in ATL.

Aneuploidy↗
PubMed1986

Selective inhibition of stimulation responses of neutrophils by membrane modulators.

Polymorphonuclear leukocytes undergo a series of morphological and biochemical changes in response to various chemical stimuli. Transmembrane potential change is an early event that follows stimulation and membrane depolarization may act as a trigger for superoxide generation. To determine if there is a correlation between membrane depolarization and superoxide generation, we investigated the effects of different membrane modulators on stimulus-dependent depolarization. The membrane modulators mepacrine, chlorpromazine and cepharanthine inhibited the superoxide generation produced by chemotactic peptide, FMLP, and/or digitonin in neutrophils. Inhibitory profiles of the activation parameters, however, demonstrate that membrane depolarization is not associated with superoxide generation: FMLP-induced depolarization was inhibited by the modulators tested and was accompanied by the suppression of superoxide generation, but the depolarization produced by digitonin was stimulated somewhat by these drugs. Our results indicate that receptor-mediated membrane depolarization is not a necessary event for the activation of superoxide generation by digitonin.

Animals↗
PubMed1986

Effect of calcium ion on fatty acid-induced generation of superoxide in guinea pig neutrophils.

When phospholipases of plasma membranes are activated by certain stimuli, unsaturated fatty acids are liberated. Because unsaturated fatty acids enhance the transmembrane movement of calcium ions, the fatty acids released may modulate intracellular calcium homeostasis in various cells, including neutrophils. To determine the physiological function of these unsaturated fatty acids, we studied the effects of various fatty acids on superoxide generation and on changes in intracellular calcium contents of guinea pig neutrophils. Some unsaturated fatty acids, arachidonate and linoleate, stimulated the rate of superoxide generation concomitant with the increase in the amount of intracellular calcium. In contrast, the saturated fatty acid, myristate, stimulated the generation of superoxide without affecting the content of intracellular calcium. The stimulating actions of arachidonate and myristate were increased dramatically by the presence of a low concentration (1 microM) of extracellular calcium ion. The rate of superoxide generation in fatty acid-treated neutrophils was inhibited by chlorpromazine, an inhibitor of such calcium-binding proteins as C-kinase. These and other observations suggest that liberated unsaturated fatty acids increase the amount of intracellular calcium and enhance C-kinase activity also that the increased activity of the enzyme is involved in the chain of events leading to the stimulation of superoxide generation in fatty acid-treated neutrophils.

Animals↗
PubMed1986

[Benign clear cell tumor of the lung--a study of immunohistochemistry].

A case of benign clear cell tumor of the lung was investigated immunohistochemically and histochemically. The tumor cells showed a packed proliferation pattern composed of two cell types. The one had polygonal, abundant eosinophilic cytoplasm, and the other had clear cytoplasm. These cells contained glycogen in the cytoplasm, detected by PAS and diastase treatment. Immunohistochemically, the tumor was strongly and diffusely stained by anti-vimentin antibody. And anti-NSE and S-100 protein antibodies were also positive in part. But anit keratin, Factor VIII, desmin, myoglobin and myosin antibodies were entirely negative. These results suggest that this tumor is a special neoplasia originating from neural tissue.

Histocytochemistry↗
PubMed1986

Griffonia simplicifolia I-A4 staining of mice glomerular tufts and its alteration in diabetic mice.

An isolectin from Griffonia simplicifolia (GS) seed--GSI-A4--stained the outer aspect of glomerular tuft (GT) intensely in the kidneys of ICR, C57BL/6J, BALB/c and NSY mice. Loss of the GSI-A4 staining was observed in the sclerotic areas of glomeruli in diabetic mice (NSY mice). This interesting staining will be useful for the analysis of the constitutions of GT in various experimental models of renal glomerular diseases in mice.

Animals↗
PubMed1986

[Nuclear DNA fluorocytophotometric analysis of leukemic cells in adult T-cell leukemia/lymphomas (ATLL)].

The nuclear DNA content of the leukemic cells in six cases of ATLL and one of peripheral T-cell malignant lymphoma (PTML) were analyzed by fluorocytophotometry, simultaneously evaluating the nuclear shape and the longest nuclear axis (LNA). The leukemic cells, characterized by the nuclear shape and LNA, had a little hyperdiploid DNA content, and they belonged to GO/GI cells. The life span of the leukemic cells was suggested to be as short as two to three weeks or much longer than the survival time of the patients, evaluating the change of the LNA histogram under chemotherapy from the diagnosis up to the patients' death. One of the ATLLs, showing small leukemic cells and a clinical course of more than three years, might be a new entity, T-CLL-like ATLL.

Adult↗
PubMed1986

Metabolic response of polymorphonuclear leukocyte to arachidonic and linoleic acids.

Various stimuli act on polymorphonuclear leukocytes (PMN), activating membrane-bound phospholipase A2 and C, and diglyceride lipase and then liberating unsaturated fatty acids (USFAs). These liberated USFAs are immediately metabolized through various metabolic pathways such as cyclooxygenase, lipoxygenase, phosphatidylinositol metabolism etc. It is possible that the metabolic intermediates of these pathways reveal various physiological actions. This work was undertaken to clarify whether stimuli on PMN depend on these USFAs themselves or on their oxidation products. The following results were obtained: 1. USFAs such as arachidonate and linoleate stimulate PMN, accelerating superoxide (O2) generation, depolarization of membrane potential and increase in [Ca2+]i. 2. Oxidation products of USFAs have no stimulative effect on PMN. The decrease in the stimulative effect of these USFAs following their oxidation is proportional to the quantitative decrease in non-oxidized linoleate. 3. USFAs accelerate membrane permeability of Ca2+, and their oxidation products enhance non-specific membrane permeability in proportion to the formation of monohydroxy compound. These results suggest that stimulative effects of USFAs on PMN do not depend on their oxidation products but on unoxidized fatty acids. Furthermore, among the oxidation products of the USFAs, monohydroxy compound acts as a strong perturber of membrane and accelerates membrane permeability.

Arachidonic Acid↗
PubMed1985

HTLV-positive and -negative T-cell lymphomas. Morphological and immunohistochemical differences between European and HTLV-positive Japanese T-cell lymphomas.

A total of 56 cases of malignant lymphoma presumed to be of peripheral T-cell origin were investigated with regard to histological and immunohistochemical features. The goal of the study was to determine whether virus-associated T-cell lymphomas can be morphologically or immunohistochemically distinguished from presumably virus-negative T-cell lymphomas. The cases came from endemic and non-endemic regions of Japan, the United Kingdom (including 4 Caribbean cases) and the Federal Republic of Germany. Sera of all Japanese and Caribbean patients and 8 German patients were tested for antibodies to adult T-cell leukaemia virus-associated antigen HTLV-A. In all cases sections were examined blind by 5 well-trained histopathologists. In most cases cryostat sections could be prepared from fresh tissue specimens and stained with a large panel of monoclonal antibodies. All HTLV-A-positive cases were morphologically classifiable as the pleomorphic type of T-cell lymphoma. Approximately 70% of the tested cases of pleomorphic T-cell lymphoma, however, showed a positive serum reaction for HTLV-A. All other types of peripheral T-cell lymphoma (T-immunoblastic lymphoma, chronic lymphocytic leukaemia of T type, T-zone lymphoma, "AILD type" and lymphoepithelioid cell lymphoma) were HTLV-A-negative and mostly observed in European patients. Thus virus-associated T-cell lymphomas appear to be invariably of the pleomorphic type; but pleomorphism is not specific to HTLV-A-positive cases. This was also evident from the results of an experiment in which 2 Japanese histopathologists attempted to recognize HTLV-A positivity in a blind study of pleomorphic T-cell lymphomas. A maximum of about 80% of cases were correctly identified, with about 10% false-positive diagnoses (in HTLV-A-negative or presumably negative cases) and 10% false-negative diagnoses. The immunohistochemical analysis revealed not only many common features but also 2 distinct differences between HTLV-A-positive and -negative T-cell lymphomas. All but one of the HTLV-A-positive cases showed reactivity with anti-Tac and all cases in the virus-positive group were negative for TU14. All other cases were Tac-negative and approximately 65% of these cases exhibited reactivity with TU14. Preliminary cytogenetic observations suggest that there are also differences in specific chromosome aberrations.

Antibodies, Monoclonal↗