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Biomedical subjects

R Tanaka

Publications and source records attributed to R Tanaka.

At least 595 records · Page 33Linked to original sources
PubMed1988

In vivo and in vitro effect of adoptive immunotherapy of experimental murine brain tumors using lymphokine-activated killer cells.

Adoptive immunotherapy for the experimental murine brain tumor was investigated by using lymphokine-activated killer (LAK) cells both in vitro and in vivo. Supernatants of 48-h culture medium of spleen cells from Wistar rats in the presence of concanavalin A were used as interleukin 2 (IL-2). LAK cells were generated by cocultivation of spleen cells from Fischer rats with IL-2 with the peak reactivity on Day 2 or 3 of culture. Lytic activity was observed against not only syngenic tumor cells but also allogenic and xenogenic tumor cells, while no lytic activity was observed against normal brain cells. The cell depletion test, dye exclusion test, and immunofluorescence method using monoclonal antibodies revealed that LAK cells partially belonged to the population of the activated T-cell group, but the precursor cells did not react with any monoclonal antibodies used. On the basis of these results in vivo study was performed. LAK cells and immune spleen cells were adoptively transferred to the rats i.v. or intratumorally (i.t.) on the seventh day after the inoculation of T9, a gliosarcoma induced by methylcholanthrene from Fischer rats, into the right basal ganglia. Then the survival rate and necrotic foci were compared between the groups treated with those cells and the control. The survival rate of the groups treated with LAK cells was significantly higher than that of the control (administered i.v.; P less than 0.01, administered i.t.; P less than 0.05). But the treatment with immune spleen cells was not effective. The incidence and area of necrotic foci in the tumors treated with LAK cells were greater than those of the others. Microautoradiography was also performed using [3H]thymidine-labeled LAK cells, which were administered i.v. to the models on the 14th day after the inoculation of T9. It was revealed that LAK cells accumulated in the lung shortly after the administration and then in the liver and spleen, especially in the white pulp. IL-2 inhibitor activity of the sera from the tumor-bearing rats was greater than that of normal rats (P less than 0.001), but it was depressed markedly by cyclophosphamide (P less than 0.01). The adoptive transfer of LAK cells may be one of the effective treatments of malignant brain tumor. The nature of IL-2 inhibitors is necessary to be clarified for more effective immunotherapy.

Animals↗
PubMed1988

Gelatinases of metastatic cell lines of murine colonic carcinoma as detected by substrate-gel electrophoresis.

Gelatinases were detected in the conditioned medium of murine colonic carcinoma cells by SDS-polyacrylamide gel electrophoresis using gels copolymerized with gelatin. Several gelatinase activities differing in molecular weight were detected but the major activities migrated with molecular weights of 60,000 and 95,000. The enzymes did not hydrolyze bovine serum albumin or casein, and required calcium for activity. All of the gelatinase activities were inhibited by EDTA, 1,10-phenanthroline and dithiothreitol but not by N-ethylmaleimide and phenylmethylsulfonyl fluoride. The 95,000 dalton gelatinase was separated from the 60,000 dalton gelatinase by affinity chromatography on Ricinus communis agglutinin-agarose, and the former activity was markedly increased in highly metastatic cell lines as compared with its activity in poorly metastatic cell lines.

Animals↗
PubMed1988

Sialosyl cholesterol induces morphological and biochemical differentiations of glioblasts without intracellular cyclic AMP level rise.

Synthesized sialosyl cholesterols, alpha- and beta-D-N-acetylneuraminyl cholesterols (alpha-SC and beta-SC), induced the morphological conversion of normal rat glioblasts from a flat epithelioid morphology to an astrocytic process-bearing (stellate) morphology resembling the conversion by glia maturation factor (GMF). The stellogenic effects were rapid and detectable within 1 h after drug stimulation, and irrelevant to the intracellular cyclic adenosine monophosphate (cAMP) levels. The morphological alteration was ascertained by the fluorescence-visualization of cytoskeletons: alpha-SC elicited the reorganization of GFA protein network to the formation of bundles, the destruction of stress fiber, and the redistribution as plasmalemmal constituents. alpha-SC also evoked biological differentiations represented by an elevation of glial marker proteins, S-100 protein and GFA protein. The results provide a possibility that SC incorporated into plasma membrane may cause morphologically and biochemically astrocyte-like differentiations of glioblast through the alteration of membrane characteristics, the cytoskeletal anchorages to the membrane, the affinity of receptors, and/or the postreceptor responses distinct from cAMP-production system.

Animals↗
PubMed1988

Disorder in reciprocal innervation upon initiation of voluntary movement in patients with Parkinson's disease.

Reciprocal innervation of the soleus motoneurones upon initiation of voluntary ankle dorsiflexion was investigated in eight patients with Parkinson's disease. H-reflex and visually guided step tracking methods were used for testing motoneurone excitability and for controlling the timing of movement initiation, respectively. While reciprocal inhibition appeared almost simultaneously with the agonist electromyographic (EMG) onset in normal subjects (Kagamihara and Tanaka 1985), facilitation appeared in the majority of patients under the same onset condition. It increased slowly, reaching a maximum at about 100 ms after the EMG onset. It then subsided slowly at around 200-300 ms, and was replaced thereafter by an inhibitory effect. No coactivation of the soleus muscle was detected electromyographically. The facilitation between the EMG onset and the onset of mechanical contraction was attributed to the direct effect of the descending command from the brain, suggesting a certain disorder in controlling the system for reciprocal innervation.

Adult↗
PubMed1988

Application of flow cytometry to differentiating Exophiala dermatitidis, E. moniliae and E. jeanselmei from each other.

We applied a flow cytometry apparatus (FCM) to differentiating Exophiala dermatitidis, E. moniliae and E. jeanselmei from each other. The wavelength of the argon laser emitted from the FCM was 488 nm and the aperture of nozzle from which the stream of fluid containing single cells was blown out was 100 micron. By irradiating the stream with laser by either the forward light scatter (FLS) or by the perpendicular light scatter (PLS), we were able to get two pieces of informations. Histograms displayed by the FLS indicate the cell size, while dot displays by the PLS reflect the cell structure. As a result, E. dermatitidis was clearly differentiated from either E. moniliae or E. jeanselmei by their histograms by FLS. In addition, dot displays by the PLS differentiated E. moniliae from E. jeanselmei. In conclusion, flow cytometry is available for differentiating E. dermatitidis, E. moniliae and E. jeanselmei from each other.

Cell Differentiation↗
PubMed1988

Correlation of DNA ploidy and morphological features of human glioma cell cultures with the establishment of cell lines.

Eleven gliomas were serially cultivated and examined for DNA distribution by flow cytometry and simultaneously for morphological features by light microscopy at the various passage levels until passage 50 at most. Seven gliomas (four low-grade gliomas, three anaplastic gliomas) showed a similar DNA distribution pattern with a main diploid and small tetraploid peaks at various passages. In this group, only one culture formed a permanent cell line, whereas six cultures showed a limited growth ranging from 6 to 24 passages. In contrast, the other four gliomas (each an anaplastic glioma) showed a marked change of DNA distribution through passages and finally a single DNA aneuploid population prospered. Each of these four gliomas yielded established cell lines. Thus, it is suggested that the change of DNA ploidy and prosperity of DNA aneuploid populations in flow cytometry might be used as early and reliable indices for the later establishment of glioma-derived permanent cell lines. Since the changes of DNA distribution are frequently associated with the morphological changes, as seen in the latter group, careful tracing of morphological features is valuable in determining of the fate of cultures, especially in the absence of a flow cytometer. The correlation between the potential to become established cell lines and histology of the original gliomas is also discussed.

Adult↗
PubMed1988

An immunohistochemical study of cytokeratin and glial fibrillary acidic protein in choroid plexus papilloma.

Cellular localization of cytokeratin and glial fibrillary acidic protein (GFAP) was examined in two normal choroid plexuses and five choroid plexus papillomas by the peroxidase-antiperoxidase (PAP) method and double immunofluorescence (IFL) microscopy. Cytokeratin was observed in the majority of epithelial cells in all samples of normal and neoplastic choroid plexuses. On the other hand, GFAP was observed in some of the constituent epithelial cells in two cases of papilloma. Most of these GFAP-positive papilloma cells were simultaneously positive for cytokeratin, as could be seen by the PAP stainings of serial sections and by the double IFL stainings of the same sections. From these findings, it was suggested that normal and neoplastic choroid plexus epithelial cells usually express cytokeratin and that some of the neoplastic cells can simultaneously express both cytokeratin and GFAP.

Adult↗
PubMed1988

Immunohistochemical analysis of tumor-infiltrating lymphocytes and major histocompatibility antigens in human gliomas and metastatic brain tumors.

A subpopulation of tumor-infiltrating lymphocytes (TILs) and the expression of major histocompatibility complex (MHC) antigens of the tumor cells were examined in 14 glioma and 13 metastatic brain tumor tissues. In both tumors, most of the TILs were T lymphocytes, and both phenotypes of the cytotoxic/suppressor and helper/inducer T lymphocyte were found. On examination of MHC antigens, beta 2-microglobulin was shown intensely on tumor cells in all cases, and the monomorphic determinant of the human leukocyte antigen (HLA-DR) was shown in 10 glioma and in 5 metastatic cases. The correlation between the number of TILs and MHC antigen expression on tumor cells was equivocal as a whole in cases of both glioma and metastatic brain tumor.

Adolescent↗
PubMed1988

Cyclic nucleotides and the activity of glia maturation factor in the hypoplastic cerebellum of developing jaundiced Gunn rats.

Developmental changes of cyclic nucleotides were studied in the hypoplastic cerebellum of jaundiced Gunn rats over the period of postnatal days 8 to 30. The mitogenic activity of glia maturation factor was also measured at day 15. In jaundiced homozygotes (jj), the amount of cyclic GMP on a protein basis was not significantly different from that in control heterozygotes (j+) at either day 8 or 15, but at day 30 it was reduced to about 19% of the control. On the other hand, a lowered nucleotide level on a wet weight basis in jj rats was already statistically significant at day 15. In contrast to cyclic GMP, the rates of increase of cyclic AMP on a wet weight basis were almost the same in the two groups of rats, but the nucleotide levels on a protein basis at days 15 and 30 were a little, but significantly, higher in jj rats than in j+ rats. The activity of glia maturation factor in jj rats was found to be 1.5-3 times as high as that in j+ rats. Possible implications of the present results are discussed.

Animals↗
PubMed1988

Analysis of peroxidase-negative acute unclassifiable leukemias by monoclonal antibodies. 1. Acute myelogenous leukemia and acute myelomonocytic leukemia.

In this study, pretreatment peripheral and/or bone marrow blasts from 12 patients with acute unclassifiable leukemia (AUL) expressing the myeloid-related cell-surface antigen (CD 11) were isolated for further analysis. Despite a lack of myeloperoxidase (MPO) activity, 1 patient's blasts contained cytoplasmic Auer rods. The circulating blasts from another patient expressed MPO while maintaining the same surface phenotype during 20 months of clinical follow-up. In addition, the blasts from 3 cases demonstrated both myelomonocytic and monocyte-specific surface antigens, whereas the remaining 9 cases completely lacked any monocyte-specific antigen detectable by monoclonal antibodies, Mo2, My4 and Leu M3 (CD 14). The first case eventually was diagnosed as acute myelomonocytic leukemia and the second as acute myelogenous leukemia by means of immunophenotypic analysis using flow cytometry (FACS IV). In addition, the presence of MPO protein was identified in the cytoplasm of blast cells from 5 patients with AUL by means of a cytoplasmic immunofluorescence test using a monoclonal antibody (MA1). Our study indicates that non-T, non-B AUL expressing OKM1 (CD 11) antigens include acute leukemias which are unequivocally identifiable as being of either myeloid or myelomonocytic origin. However, further investigations, including immunophenotypic and cytoplasmic analysis, ultrastructural cytochemistry and gene analysis with molecular probes (tests applicable to normal myeloid cells), are necessary in order to determine the actual origin of blasts and to recognize the differentiation stages of the various types of leukemic cells from patients with undifferentiated forms of leukemia.

Antibodies, Monoclonal↗
PubMed1988

Pseudogout associated with primary hyperparathyroidism: management in the immediate postoperative period for prevention of acute pseudogout attack.

Three cases of pseudogout associated with primary hyperparathyroidism are reported. Preoperative radiological studies revealed association of pseudogout. Considering the frequent development of acute pseudogout attack following parathyroidectomy, prevention of a sudden decrease in the serum calcium concentration was attempted using calcium supplement therapy starting on the first postoperative day in all three cases. Serum calcium slowly decreased to the normal range, and the postoperative courses were uneventful. From these experiences, we advocate that calcium supplement therapy is worth trying for the prevention of acute pseudogout attack following parathyroidectomy.

Aged↗