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N Tabata

Publications and source records attributed to N Tabata.

At least 73 records · Page 4Linked to original sources
PubMed1996

Intracellular localization of antigens recognized by anti-vimentin monoclonal antibodies (mAbs): cross-reactivities of anti-vimentin mAbs with other cellular components.

Monoclonal antibodies were raised against immunoaffinity-purified fusion regulatory protein (FRP)-1 complex from membrane fraction of HeLa cells. Immunoblotting and immunoprecipitation studies showed all ten antibodies reacted with a 55 kDa band of cell lysate and purified vimentin. Interestingly, one of the antibodies (mAb57) cross-reacted with purified tropomyosin and myosin. Further analyses using vimentin chemically cleaved by 2-nitro-5-thio-cyanobenzoic acid, and lambda gt 11 cDNA which encoded a partial sequence of vimentin indicated that six mAbs recognized epitopes between amino acids 1 and 313 and the other four mAbs recognized epitopes in the area between residues 314 and 326. Indirect immunofluorescence microscopy using 3% formalin-fixed, 0.1% Triton X-100 treated HeLa cells revealed that seven antibodies stained various intracellular components other than vimentin, while three antibodies stained vimentin filaments alone. Furthermore, flow cytometric analysis showed one of the antibodies (mAb25) clearly stained the surface of unfixed HeLa cells. All immunofluorescent findings were the same when HeLa, baby hamster kidney (BHK) and murine L229 cells were examined. These results indicate that we could obtain unique anti-vimentin mAbs which show cross-reactivities with previously undescribed cell surface and intracellular molecules including tropomyosin and myosin. Taken together, there are two possibilities that explain our findings: (1) The unknown molecules may have structural similarity to vimentin. (2) Our anti-vimentin mAbs can react specifically with structurally distinct epitopes present on both unknown molecules and vimentin. In either case, our cross-reactive mAbs, which recognized undescribed epitopes on vimentin, maybe provide useful tools for studying intermediate filaments and related cellular components.

Animals↗
PubMed1996

Rhabdomyolysis following administration of cyclophosphamide: a case report in a BMT recipient.

Massive rhabdomyolysis followed by myocardial necrosis was observed in a 14-year-old patient undergoing allogeneic bone marrow transplantation for severe aplastic anemia. Rhabdomyolysis was preceded by the administration of cyclophosphamide as part of a preparative regimen for transplantation Although the specific etiology of this rhabdomyolysis is still unknown, an association with high-dose cyclophosphamide should be noted.

Bone Marrow Transplantation↗
PubMed1995

On an accident by liquid nitrogen--histological changes of skin in cold.

Two young researchers were found lying beside 3 Dewar flasks for liquid nitrogen in a cold experimental room of a university. They were sent to a hospital but died 1.5 h after cardiopulmonary resuscitation. One of the cadavers had dark red discoloration of the skin on the left arm at autopsy. By the histological investigation of the discolored region karyopyknosis and vacuolation of the keratinocytes were noticeably observed in the epidermis. In addition, hyperemia and edematous changes were seen. Hemoglobin (Hb) was not immunodetected in the skin tissue except intravascular erythrocytes. Therefore, these histological findings of the discolored skin can indicate that the skin damage was produced by cold due to liquid nitrogen before death. The cause of death was asphyxia due to oxygen deficiency. There were few autopsy findings which showed the participation of liquid nitrogen in the accident. But, the histological findings of the discolored region demonstrate that liquid nitrogen was involved in this accident.

Accidents, Occupational↗
PubMed1995

Identification of regions on the hemagglutinin-neuraminidase protein of human parainfluenza virus type 2 important for promoting cell fusion.

The hemagglutinin-neuraminidase (HN) and fusion (F) glycoproteins of two paramyxoviruses, human parainfluenza virus type 2 (PIV2) and simian virus 41 (SV41), were expressed in HeLa cells by transfecting with recombinant plasmid harboring each glycoprotein gene. Expressed F proteins could not induce cell fusion by themselves, but evoked prominent cell fusion when coexpressed with homologous HN proteins. It was also proved that PIV2 HN protein could weakly promote SV41 F-mediated cell fusion. By analyzing the fusion-promoting function of chimeric HN proteins of PIV2 and SV41, it was revealed that the N-terminal region (about 16% of total amino acids) of either PIV2 HN or SV41 HN protein could define the type-specific fusion-promoting function for homologous F protein. Analyses of additional chimeras indicated that the N-terminal region in PIV2 HN protein (designated region I, consisting of 94 amino acids) could be reduced to a 58-amino-acid region (region I') which was located at the membrane-proximal end of the ectodomain. Furthermore, PIV2 HN protein proved to promote cell fusion mediated by PIV4A F protein. Unexpectedly, analyses of another set of chimeras revealed that the promoting function of PIV2 HN protein for PIV4A F-mediated cell fusion was not merely carried by its region I but also by another region ranging from residue 148 to 209 (region II). Finally, it was indicated that regions I' (in the presumed stalk domain) and II (in the globular head) in PIV2 HN protein might play important roles in promoting cell fusion mediated by the F proteins.

Amino Acid Sequence↗
PubMed1995

Molecular characterization of fusion regulatory protein-1 (FRP-1) that induces multinucleated giant cell formation of monocytes and HIV gp160-mediated cell fusion. FRP-1 and 4F2/CD98 are identical molecules.

Fusion regulatory protein (FRP)-1 regulates virus-mediated cell fusion and fusion of monocytes. Eleven of fifteen N-terminal amino acids of FRP-1 were the same as the amino acid sequence of 4F2/CD98 heavy chain. FRP-1 molecules were detected in Con A- or IL-2-stimulated lymphocytes, while FRP-1 was rare on resting lymphocytes. These properties of FRP-1 are similar to those of 4F2/CD98. Treatment of monocytes with anti-4F2/CD98 mAbs resulted in cell fusion, and other mAbs directed against 4F2/CD98 induced formation of multinucleated giant cells of Cd+U2ME-7 cells, a CD4+U937 cell line transfected with the HIV gp160 gene. Both anti-4F2/CD98 and anti-FRP-1 mAbs reacted with murine L929 cells expressing human 4F2/CD98 transiently or constitutively. When Newcastle disease virus (NDV)-infected L929 cells expressing human FRP-1/CD98 were incubated with mAb 4-5-1, an anti-FRP-1 mAb, multinucleated giant cells were induced; thus, FRP-1/CD98 molecules expressed in L929 cells are functional for fusion regulatory activity.

Amino Acid Sequence↗
PubMed1995

A cell fusion-inhibiting monoclonal antibody binds to the presumed stalk domain of the human parainfluenza type 2 virus hemagglutinin-neuraminidase protein.

Previously, we obtained a neutralizing monoclonal antibody directed against the hemagglutinin-neuraminidase (HN) protein of human parainfluenza type 2 virus (PIV2), which was able to prevent cell fusion without affecting the hemagglutinating and neuraminidase activities. In this study, four escape mutants of PIV2 have been obtained under pressure of the monoclonal antibody. Intriguingly, the HN protein of each mutant proved to have two amino acid substitutions, one of which is at 83Asn or 91Lys, and another one is at 150Leu, 160Ala, or 186Met. One mutant designated F13, which has substitutions at 83Asn and 186Met in the HN protein, could not cause cell fusion in HeLa cells despite its multiple replication, while the other mutants formed typical syncytial cells. The deduced amino acid sequence of F13 fusion (F) protein proved to be identical to that of wild-type F protein, and furthermore, protein expression analyses have revealed that the low-fusion phenotype of F13 was due to its mutated HN protein, whose antigenicity to the monoclonal antibody was abolished by the single mutation at 83Asn. These observations have suggested that the principal epitope for the monoclonal antibody resides in the presumed stalk domain of the HN protein, which may play an important role in promoting cell fusion.

Amino Acid Sequence↗
PubMed1995

Successful treatment of an infant with veno-occlusive disease developed after allogeneic bone marrow transplantation by tissue plasminogen activator, heparin and prostaglandin E1.

A 15-month-old boy with severe aplastic anemia developed veno-occlusive disease (VOD) after allogeneic bone marrow transplantation (BMT), in which the preparative regimen included 50 mg/kg/day cyclophosphamide and anti-lymphocyte globulin for 4 consecutive days. The diagnosis was made based on clinical symptoms and data including, hepatomegaly, right upper quadrant abdominal pain, jaundice, ascites, coagulopathy and thrombocytopenia which was refractory to transfusions of platelet concentrate. We gave 2, 3, 5 and 5 mg/day/body of recombinant tissue plasminogen activator (tPA) followed by heparin and prostaglandin E1 (PGE1) effectively and without significant side effect on days 9, 10, 13 and 14, respectively. Clinical and biochemical improvement was steady and dramatic. We suggest that tPA following continuous heparin and PGE1 infusion may be useful in the treatment of VOD even in infantile cases.

Alprostadil↗
PubMed1995

Hydroa vacciniforme-like lymphomatoid papulosis in a Japanese child: a new subset.

An 8-year-old Japanese girl had a 9-month history of a self-healing papulovesicular eruption on her face, scalp, and neck that resembled hydroa vacciniforme (HV). Histologically, there was a dense infiltration of small lymphocytic cells and scattered large atypical cells expressing CD30. Study of gene rearrangement showed no monoclonality in the infiltrating cells. To our knowledge, this is the second case of lymphomatoid papulosis with clinical features resembling HV. However, we also found descriptions in the literature of two other Japanese children with malignant lymphoma who both initially had clinical features resembling HV. These findings suggest that these cases of HV-like disease constitute a subset of lymphomatoid papulosis that is highly likely to progress to malignant lymphoma.

Child↗
PubMed1995

Nodular melanoma in 62 Japanese patients: influence of initial surgical treatment on local recurrence and prognosis.

The incidence of malignant melanoma is much lower in Japanese than in Caucasians, and the commonest type of melanoma in Japanese is acral lentiginous melanoma (ALM). In contrast to the improved prognosis noted in ALM, it is now of increasing concern that there is a rise in both the frequency and mortality of nodular melanoma. During the 25 years from 1970 to 1994, we observed 190 patients with melanoma, including 62 nodular melanomas and 96 ALM, at the Department of Dermatology, Tohoku University Hospital, Sendai, Japan. We retrospectively reviewed the recurrence and survival rates of nodular melanoma observed. The proportion of nodular melanoma, once comprising only 24% of all melanomas, showed a sharp increase to 40% after 1982. The anatomical sites of the primary tumor were the hands and feet (29%), extremities excluding hands and feet (27%), head and neck (23%), and trunk (21%). Comparison of the stages of nodular melanoma when diagnosed showed that the proportion of stage III remained highest throughout the whole period, but that of stage II melanomas increased after 1982. After treatment, local recurrence occurred far more frequently in nodular melanoma (19%) than in ALM (1%). The prognosis of nodular melanoma was also less favorable than that of ALM, although it slightly improved after 1982; the 5-year survival rates before and after 1982 were 34 and 50%, respectively. Twenty-eight patients with nodular melanoma had underwent simple excision or incisional biopsy of the primary tumor at another institution and were later referred to us for further intensive care or for the treatment of local recurrence and/or metastases.(ABSTRACT TRUNCATED AT 250 WORDS)

Combined Modality Therapy↗
PubMed1995

Immunoelectron microscopic localization of gelatinase A in human gastrointestinal and skin carcinomas: difference between cancer cells and fibroblasts.

Previous reports revealed a discrepancy in gelatinase A localization in human cancers; i.e., protein localization in cancer cells and mRNA localization in stromal fibroblastic cells. To clarify this, we conducted immunoelectron microscopic study of gelatinase A in cancer and stromal cells in human gastrointestinal and skin carcinomas. Although both carcinoma cells and fibroblasts were positive for gelatinase A, the subcellular localizations were different. On immunoelectron microscopy, fibroblasts showed immunoreactivity in the lumen of the rough endoplasmic reticulum (rER) or in the cytosol on the surface of rER, demonstrating synthesis of the protein. Carcinoma cells showed diffuse deposition of gelatinase A in the cytosol, suggesting the accumulation of the antigen both in adenocarcinoma and squamous cell carcinoma. Immunoreactivity along the cell membrane was demonstrated in one case of skin carcinoma. Macrophages showed also diffuse deposition of gelatinase A in the cytosol. In conclusion, we found a qualitative difference of gelatinase A localization between carcinoma cells and fibroblasts, and concluded that carcinoma cells may not be important in the secretion of gelatinase A.

Adenocarcinoma↗
PubMed1995

Transient low level of IgG3 induced by sepsis.

Staphylococcus aureus sepsis developed in a 14 year old girl. Immunological evaluation revealed low level of IgG3, although total IgG level was normal. The level of IgG3 increased gradually along with the recovery from sepsis. Immunoglobulin replacement therapy might have been useful in this patient, even though the total immunoglobulin level was within normal limits.

Adolescent↗
PubMed1995

Identification of fusion regulatory protein (FRP)-1/4F2 related molecules: cytoskeletal proteins are associated with FRP-1 molecules that regulate multinucleated giant cell formation of monocytes and HIV-induced cell fusion.

Fusion regulatory proteins (FRPs) regulate virus-mediated cell fusion and multinucleated giant cell formation of monocytes. Anti-FRP-1 mAbs immunoprecipitated 80 kDa and 38 kDa proteins from HeLa cells. After long exposure other bands were detected, suggesting the presence of molecule(s) associated with FRP-1. To identify the molecule(s), we prepared monoclonal antibodies against immunoaffinity-purified FRP-1 complex derived from membrane fractions of HeLa cells. Immunofluorescence microscopy revealed that these monoclonal antibodies recognized the intracytoplasmic molecules in HeLa cells. Using immunoblotting, the antibodies reacted with 200 kDa, 70 kDa, 55 kDa and 35 kDa molecules, so we designated these molecules as FRP-related molecules (FRMs). Subsequently, we performed gene cloning from a HeLa lambda gt11 cDNA library using anti-FRM mAbs and immunoblotting analysis with either purified cytoskeletal proteins or specific antibodies against various cytoskeletal proteins. Three kinds of positive clone were obtained, which encoded partial sequences of vimentin, tropomyosin, and heat shock cognate protein 70 (hsc70). The 200 kDa molecule was expected to be a myosin heavy chain, judging from the immunoblotting pattern. Immunoblotting confirmed that these purified proteins were readily recognized by anti-FRM mAbs. Furthermore, anti-vimentin and anti-myosin mAbs reacted with the precipitates by anti-FRP-1 mAb, indicating a physical association between FRP-1 molecules and these cytoskeletal proteins. When anti-FRP-1 mAb was added to culture fluids of HeLa cells, the cell-shape and immunofluorescence-pattern stained with anti-FRM mAbs changed. Taken together, the fusion regulatory molecular complex is suggested to consist of at least FRP-1, hsc70, actomyosin and vimentin systems.

Antibodies, Monoclonal↗
PubMed1995

Pyripyropenes, Novel ACAT inhibitors produced by Aspergillus fumigatus. III. Structure elucidation of pyripyropenes E to L.

Eight new pyripyropenes, E to L, were isolated from the culture broth of Aspergillus fumigatus FO-1289-2501 selected as a higher producer by NTG mutation. Structural elucidation indicated that all the pyripyropenes have the same pyridino-alpha-pyrone sesquiterpene core as pyripyropenes A to D. Among them, pyripyropene L showed the most potent inhibition against acyl-CoA: cholesterol acyltransferase (ACAT) activity with an IC50 value of 0.27 microM in rat liver microsomes.

Animals↗
PubMed1995

Terpendoles, novel ACAT inhibitors produced by Albophoma yamanashiensis. II. Structure elucidation of terpendoles A, B, C and D.

Structures of terpendoles A, B, C and D, novel acyl-CoA: cholesterol acyltransferase (ACAT) inhibitors, were determined by spectroscopic studies. All terpendoles consist of diterpene and indole moieties in common. Terpendoles A, C and D possess an additional isoprenyl unit via oxygen atom(s) of their diterpene moieties. The relative stereochemistries of terpendoles C and D were confirmed by NOE experiments and X-ray crystallographic analysis.

Anti-Bacterial Agents↗
PubMed1995

Fudecalone, a new anticoccidial agent produced by Penicillium sp. FO-2030.

Penicillium sp. FO-2030, a soil isolate, was found to produce a new anticoccidial compound. The active compound, designated fudecalone, was isolated from the fermentation broth of the producing strain by solvent extraction, silica gel column chromatography and preparative HPLC. The structure of fudecalone was elucidated to be 3,3a,6,6a,7,8,9,10-octahydro-1-hydroxy-4,7,7-trimethyl-1H-naphtho[1,8a- c]furan-6-one mainly by spectroscopic studies including various NMR measurements. The anticoccidial activity using cell systems indicated that schizont formation of monensin-resistant Eimeria tenella was completely inhibited by fudecalone at concentrations more than 16 microM.

Animals↗
PubMed1995

Isochromophilones III-VI, inhibitors of acyl-CoA:cholesterol acyltransferase produced by Penicillium multicolor FO-3216.

New azaphilones named isochromophilones III-VI were isolated from the culture broth of Penicillium multicolor FO-3216 as inhibitors of acyl-CoA: cholesterol acyltransferase (ACAT). Their structures were elucidated by NMR and other spectroscopic analyses. The IC50 values of isochromophilones III, IV, V and VI for ACAT activity in an enzyme assay using rat liver microsomes were calculated to be 110, 50, 50 and 120 microM, respectively.

Animals↗