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N Tabata

Publications and source records attributed to N Tabata.

At least 91 records · Page 5Linked to original sources

Terpendoles, novel ACAT inhibitors produced by Albophoma yamanashiensis. III. Production, isolation and structure elucidation of new components.

Eight new components of terpendoles E to L were isolated and characterized from the culture broth of Albophoma yamanashiensis using a different production medium. All the structures were elucidated by spectroscopic analyses including various NMR experiments, indicating that all the terpendoles have the same indoloditerpene core as terpendoles A to D. Terpendoles J, K and L showed the moderate inhibition against acyl-CoA: cholesterol acyltransferase (ACAT) activity with IC50 values of 38.8, 38.0 and 32.4 microM in rat liver microsomes, respectively. But terpendoles E-I showed weak activities (IC50 145-388 microM).

Animals↗

Amidepsines, inhibitors of diacylglycerol acyltransferase produced by Humicola sp. FO-2942. I. Production, isolation and biological properties.

Humicola sp. FO-2942, a soil isolate, was found to produce a series of new inhibitors of diacylglycerol acyltransferase (DGAT). Three active compounds, designated amidepsines A, B and C, were isolated from the fermentation broth of the producing strain by solvent extraction, silica gel column chromatography, ODS column chromatography and HPLC. Amidepsines inhibit DGAT activity with IC50 values of 10.2 approximately 51.6 microM in an enzyme assay system using rat liver microsomes. Amidepsines also showed specific inhibition of triacylglycerol formation in intact Raji cells, indicating that they inhibit DGAT activity in living cells.

Acyltransferases↗

Amidepsines, inhibitors of diacylglycerol acyltransferase produced by Humicola sp. FO-2942. II. Structure elucidation of amidepsines A, B and C.

Structures of amidepsines A, B, C and D, diacylglycerol acyltransferase (DGAT) inhibitors, were determined by spectroscopic studies including various NMR measurements. They were elucidated as 2-hydroxy-4-[[2-hydroxy-4-[(2,4-dimethoxy-6-methylbenzoyl) oxy]6-methylbenzoyl]-oxy]-6-methylbenzoic acid N-alanine amide for amidepsine A, 2-hydroxy-4-[[2-hydroxy-4-[(2-hydroxy-4-methoxy-6-methylbenzoyl) oxy]6-methylbenzoyl]oxy]-6-methylbenzoic acid N-alanine amide for amidepsine B and 2-hydroxy-4-[[2-hydroxy-4-[(2-hydroxy-4-methoxy-6-methylbenzoyl) oxy]6-methylbenzoyl]oxy]-6-methylbenzoic acid N-valine amide for amidepsine C. Amidepsine D was identified with 2,4-di-O-methylgryphoric acid.

Acyltransferases↗

Tissue distribution of fusion regulatory protein-1 and fusion regulatory protein-2.

OBJECTIVE: To show which organs (tissues or cells) express fusion regulatory protein-1 and -2. DESIGN: Tissue distribution of fusion regulatory protein-1 and -2 was investigated by indirect immunofluorescence and indirect immunoperoxidase techniques on cryostat tissue sections, using anti-fusion regulatory protein-1 and -2 monoclonal antibodies. RESULTS: Immunohistochemical analysis of human tissue sections revealed the expression of fusion regulatory protein-1 on hair follicle epithelium, skeletal muscle sarcolemma, some bone marrow stem cells, stomach surface and glandular epithelia, pancreatic islets, kidney proximal tubules, testicular seminiferous tubules, follicular epithelium and ova in the ovary, and parathyroid gland. Fusion regulatory protein-2 was expressed on kidney glomerular basement membrane and many glandular epithelia, such as the skin, stomach, thyroid gland, and lung. CONCLUSIONS: The distribution suggested that the expression of fusion regulatory protein-1 might be related to proliferation, peptide or protein secretion, and cell fusion. The distribution of fusion regulatory protein-2 was identical to that of the alpha 3 subunit of integrin.

Antigens, Surface↗

Successful bone marrow transplantation in a child with combined IgG subclass deficiency and neutropenia.

An 8-year-old boy with combined IgG1 deficiency and neutropenia underwent allogeneic BMT from his HLA-identical, MLC-negative sister, because immunoglobulin (Ig) infusions and prophylactic antibiotics failed to prevent life-threatening infections. Conditioning was with busulfan and cyclophosphamide, MTX and CYA were given for the prophylaxis of GVHD. For 16 months after BMT no serious infections have occurred and serum IgG1 levels have returned to the normal range without Ig replacement. BMT may be appropriate treatment for patients with IgG subclass deficiency who rarely respond to conservative therapy.

Bone Marrow Transplantation↗

Expression of fusion regulatory proteins (FRPs) on human peripheral blood monocytes. Induction of homotypic cell aggregation and formation of multinucleated giant cells by anti-FRP-1 monoclonal antibodies.

Fusion regulatory proteins (FRPs) are newly defined cell surface molecules that enhance and/or induce virus-mediated cell fusion. Anti-FRP-1 Abs reacted with all of the established cells derived from humans and monkeys, whereas FRPs were found to be selectively expressed on a fraction of monocytes in human PBMCs. Granulocytes expressed no FRP-1 molecules, but approximately 18% of granulocytes expressed FRP-2 molecules. Alveolar macrophages also expressed FRP-1 molecules. FRP-1 expression was enhanced by culture of monocytes, but CD14 expression was not influenced by cultivation. Anti-FRP-1 Abs induced homotypic cell aggregation and multinucleated giant cell formation of monocytes. Anti-beta 2 integrin Ab blocked anti-FRP-1 Ab-induced cell aggregation, and anti-beta 1 integrin Ab and fibronectin inhibited anti-FRP-1 Ab-induced polykaryocyte formation. There was no competitive binding to monocytes between anti-FRP-1 Ab and anti-beta 1 or anti-beta 2 integrin Ab or fibronectin. Furthermore, there was no enhancement of beta 1 and beta 2 integrin expression by anti-FRP-1 Ab on monocytes. These findings suggest that anti-FRP-1 Ab activated integrin systems, and that the functions of anti-FRP-1 Ab were demonstrated through the activated integrin systems. Furthermore, it is inferred that integrin systems are involved in polykaryocyte formation of monocytes.

Amino Acid Sequence↗

Case report: repeated neonaticides in Hokkaido.

Five cases of repeated neonaticides were reported in Hokkaido, the northernmost island of Japan, during the 10 years from 1983 to 1992. Four or more neonates were involved in each case by each mother. All the suspected mothers were not mentally ill. Two of them were single and the rest were married. Each husband was not aware of the pregnancy of his wife, because he was away from home very often. The main motive of murder seemed to be economic and/or to save appearances. Sentences were 1 year penal servitude with a stay of 3 years for one case, but 30-42 months in prison for the other four cases. We rarely find reports of repeated infanticides committed by the same mother in European countries and the United States.

Adult↗

Fusion properties of cells constitutively expressing human parainfluenza virus type 4A haemagglutinin-neuraminidase and fusion glycoproteins.

We established HeLa cell lines that constitutively expressed the fusion (F) and/or haemagglutinin-neuraminidase (HN) glycoproteins of human parainfluenza virus type 4A (PIV-4A) and used them to analyse the roles of these glycoproteins in virus-induced cell fusion. No syncytium formation occurred, even in HeLa cells expressing both the F and HN proteins (HeLa-4aF+HN cells). Also no syncytium was found in a mixed culture of cells expressing the F protein (HeLa-4aF) and the HN protein (HeLa-4aHN). Syncytia were observed in HeLa-4aF cells transfected with the HN gene, but no syncytium formation was found in HeLa-4aHN cells transfected with the F gene. Co-cultivation of HeLa-4aF+HN cells with HeLa-4aF cells generated large polykaryocytes, whereas co-cultivation with HeLa-4aHN cells induced no cell fusion. Infection of HeLa-4aF cells with PIV-4A generated large syncytia and degenerated nuclei, whereas little or no polykaryocytes were found in HeLa-4aHN cells infected with PIV-4A. From the above findings, the following conclusions were drawn: (i) the expression of both the F and HN proteins in the same cell is necessary for cell fusion; (ii) the expression of the F protein alone enhances susceptibility to cell fusion; (iii) the constitutive expression of the HN protein promotes resistance to paramyxovirus-induced cell fusion.

Cell Fusion↗

T cell subsets in peripheral blood and cerebrospinal fluid from children with aseptic meningitis.

T cell subsets in peripheral blood (PB) and cerebrospinal fluid (CSF) obtained from patients with aseptic meningitis were studied using quantitative two-color fluorescence analysis with a flow cytometer. The percentage of HLA-DR+/CD3+ lymphocytes (activated T cells) in CSF was significantly increased in the recovery phase when compared to the acute phase, while no significant change in the activated T cells in PB was observed. More interestingly, CD4+ T lymphocytes in CSF were increased in the acute phase and subsequently decreased in the recovery phase. Instead, CD8+ T lymphocytes gradually accumulated into the CSF in the recovery phase, resulting in a successive decrease in the CD4/CD8 ratio. On the other hand, the CD4/CD8 ratio in PB remained normal during the course of aseptic meningitis. The present results suggest that T lymphocytes (CD4+ subset in the acute phase and CD8+ in the recovery phase) could be infiltrated and further activated at the site of inflammation, possibly in the subarachnoid space in the patients with aseptic meningitis.

Antibodies, Monoclonal↗

Arohynapenes A and B, new anticoccidial agents produced by Penicillium sp. Taxonomy, fermentation, and structure elucidation.

Penicillium sp. FO-2295, a water isolate, was found to produce a series of new anticoccidial compounds. Two active compounds, designated arohynapenes A and B, were isolated from the fermentation broth of the producing strain by solvent extration and preparative HPLC. Arohynapene A was deduced to be (2E,4E)-5-(5-hydroxy-2,6,8-trimethyl-5,6,7,8-tetrahydronaphtale ne)-2,4- pentadienoic acid, and arohynapene B was (2E,4E)-5-(2-hydroxymethyl-6,8-dimethyl-5,6,7,8-tetrahydronapht alene)-2,4- pentadienoic acid. Arohynapenes inhibited the growth of Eimeria tenella in an in vitro assay using BHK-21 cells as a host. No schizont in the cells was observed at concentrations ranging above 35.0 microM and 7.0 microM for arohynapenes A and B, respectively.

Coccidiostats↗

Cytosaminomycins, new anticoccidial agents produced by Streptomyces sp. KO-8119. I. Taxonomy, production, isolation and physico-chemical and biological properties.

Streptomyces amakusaensis KO-8119, a soil isolate, was found to produce a series of new anticoccidial compounds. Four active compounds, designated as cytosaminomycins A, B, C and D, were isolated from the fermentation broth of the producing strain by solvent extraction, silica gel column chromatography and preparative HPLC. Cytosaminomycins inhibited the growth of Eimeria tenella in an in vitro assay system using primary chicken embryonic cells as a host. No schizont in the cells was observed at concentrations ranging from 0.3 to 0.6 microgram/ml for cytosaminomycins A, B and C, and at 2.5 micrograms/ml for cytosaminomycin D.

Aminoglycosides↗

CD34+ spindle-shaped cells selectively disappear from the skin lesion of scleroderma.

BACKGROUND AND DESIGN: The pathogenesis of scleroderma is still unknown. Recently, it has become possible to identify different subpopulations of dermal spindle-shaped cells using anti-CD34 and anti-factor XIIIa antibodies. To elucidate whether entire populations of dermal fibroblasts or only a subpopulation of cells are involved in the fibrosis of scleroderma, we compared the staining pattern of these antibodies and antiprocollagen antibody in paraffin-embedded skin sections from the lesions of 27 patients with scleroderma and 15 patients with other collagen diseases and from normal skin of 17 subjects. Cryostat sections from both involved and uninvolved skin of four patients with scleroderma were also stained with anti-CD34, anti-factor XIIIa, and anti-proline-4-hydroxylase antibodies. RESULTS: CD34+ cells were few or absent in the lesions of scleroderma, while a number of CD34+ cells were found in the lesions of other collagen diseases and in normal skin. In contrast, large numbers of factor XIIIa-and procollagen-positive cells were noted in the lesions of scleroderma. Even in the study in which cryostat sections were used, CD34+ cells were totally absent from the lesions of scleroderma, while there were numerous proline-4-hydroxylase-positive cells. Furthermore, although detectable in the clinically uninvolved skin of these patients, CD34+ cells were less frequent and more slender than those in normal skin. CONCLUSION: Immunohistologic staining with anti-CD34 and other antibodies to dermal spindle-shaped cells demonstrated a selective disappearance of CD34+ spindle-shaped cells from the lesions of scleroderma. It suggests that CD34+ cells might be important target cells in the autoreactive phenomenon in scleroderma.

Adolescent↗

An immunohistochemical study on pulmonary surfactant of infants diagnosed as sudden infant death syndrome.

Pulmonary tissues from 22 autopsy cases diagnosed as sudden infant death syndrome (SIDS) were examined by immunoperoxidase method using monoclonal antibodies against human pulmonary surfactant apoproteins. In all cases except one, a moderate or large amount of pulmonary surfactant existed in the alveolar spaces. In the cytoplasm of the alveolar type II cells of most cases, a variable number of reaction products were also recognized. This study suggested that SIDS babies suffered lethal hypoxic state, but the staining intensity of pulmonary surfactant did not show a clear difference in sleeping positions.

Humans↗

IgE-mediated hypersensitivity and contact sensitivity to multiple environmental allergens in atopic dermatitis.

BACKGROUND AND DESIGN: Atopic dermatitis (AD) is a chronic eczematous skin disease that develops in a patient with atopic diathesis, which is characterized by an increased liability to produce IgE antibodies for environmental allergens mostly derived from other living organisms. Experimentally, eczematous skin lesions cannot be induced by immediate IgE-mediated reactions alone. They are produced by cell-mediated allergic contact reactions, and recently contact sensitivity to various environmental allergens has been demonstrated in patients with AD. However, the pathologic role of IgE-mediated skin hypersensitivity or that of delayed-type hypersensitivity to various environmental allergens in AD is not fully evaluated. They have been studied separately and against only specific allergens. Thus, we performed a combined testing procedure consisting of radioallergosorbent test, prick, and scarification patch tests for eight environmental allergens in 97 Japanese adult patients with AD; 48 of them had a history of atopic respiratory diseases (ARD), whereas the remaining 49 had no history of ARD (pure AD). RESULTS: Patients with AD, particularly those with ARD (AD+ARD), showed a higher incidence of positive radioallergosorbent test and prick test results as well as patch test results against multiple environmental allergens than healthy age-matched control subjects. Among them, we found a significantly high positive correlation between radioallergosorbent test scores and patch test reactions to two allergens, Japanese cedar, and Dermatophagoides farinae allergens in patients with AD. However, the patients with AD displayed a significantly lower incidence of positive patch test reactions to Candida albicans allergen than the healthy control subjects. Patients with AD with negative C albicans patch tests tended to have higher levels of total serum IgE including anti-C albicans IgE antibody. We found negative correlations between total serum IgE levels including specific antibodies and patch test reactions to C albicans allergen. CONCLUSIONS: Except for the dissociated reactivities to C albicans allergen consisting of decreased contact sensitivity and heightened IgE response, generally both IgE-mediated skin hypersensitivity and delayed-type hypersensitivity to various environmental allergens are pronounced in patients with AD. The combined use of these in vivo and in vitro tests is useful to estimate the immunological state of patients with AD.

Adolescent↗

Sialyl LewisX expression on human Langerhans cells.

Recently, it has been demonstrated that the skin-infiltrating T cells express cutaneous lymphocyte-associated antigen, which is the ligand of E-selectin or endothelial-leukocyte adhesion molecule, suggesting that cutaneous lymphocyte-associated antigen functions as the homing receptor of the skin infiltrating T cells. In contrast, the mechanism for the migration of Langerhans cells from the bone marrow to the skin has not been clarified. Sialyl LewisX acts as a ligand for endothelial-leukocyte adhesion molecule and granule membrane protein 140. We examined the expression of sialyl LewisX in epidermal dendritic cells in human skin. Two-color immunofluorescence study on an epidermal sheet revealed that human leukocyte antigen DR+ or CD1a+ epidermal dendritic cells were partially sialyl LewisX+, although all of the sialyl LewisX+ dendritic cells were human leukocyte antigen DR+ and CD1a+. Further analysis of these dendritic cells by flow cytometry demonstrated that most of the human leukocyte antigen DR+ and CD1a+ epidermal cells expressed sialyl LewisX, although the magnitude of its expression was more variable than that of CD1a expression, and that some of human leukocyte antigen DR+ cells were clearly sialyl LewisX-. Immunoperoxidase study of normal skin showed the presence of sialyl LewisX+ dendritic cells not only in the epidermis but also in the upper dermis. These data demonstrating the heterogeneity of the expression of sialyl LewisX by epidermal Langerhans cells suggest their possible relationship to the stage of maturation as well as to the migration of Langerhans cells from the bone marrow to the skin.

Flow Cytometry↗

Loxoprofen--another NSAID associated with acute asthmatic death.

Loxoprofen sodium (sodium 2[4-(2-oxocyclopentylmethyl) phenyl] dehydrate; CAS #68767-14-6) is a nonsteroidal, inflammatory drug marketed only in Japan. A case report describes its association with an acute asthmatic death with features resembling those evoked by similar drugs. The analytic methodology is reported. The blood levels of loxoprofen were in the therapeutic range. The tissue concentrations are reported.

Anti-Inflammatory Agents, Non-Steroidal↗