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T Tada

Publications and source records attributed to T Tada.

At least 487 records · Page 27Linked to original sources

Activation of calpain in myocardial infarction: an immunohistochemical study using a calpain antibody raised against active site histidine-containing peptide.

Tissue damage resulting from ischemia due to myocardial infarction is thought to be intensified by the proteolytic action of endogenous enzymes. Calpain (calcium dependent cysteine protease) is considered to be a highly likely candidate, since it is activated by calcium ion which increases in concentration under conditions of ischemia. We prepared a mono-specific antibody against the active site histidine stretch, Lys-Leu-Val-Lys-Gly-His-Ala-Tyr-Ser-Val, in the calpain 80 kDa large subunit. The specificity of the antibody was verified by its inhibitory effect on the caseinolytic activity of both mu- and m-calpains, western blotting analysis, and by absorption with the antigen peptide. The antibody was used to localize the intracellular distribution of activated calpains in infarcted regions of the human heart. The results showed that myocardial cells affected by ischemia were stained by the antibody, allowing damaged cells to be distinguished from cells of unaffected regions and that the immunostained regions were essentially the same regions as those identified by dense eosinophilic staining with hematoxylin and eosin. However, the staining pattern obtained with the antibody, was characteristic in denser staining at the cell periphery, whereas the damaged cells were stained homogeneously by hematoxylin and eosin. By the former method, results of staining indicated that the activation site of the calpain proenzyme was in the peri-plasma membrane, whereas by the latter method, diffusely distributed plasma proteins such as albumin and immunoglobulins were visualized as demonstrated in earlier reports.

Animals↗

I-J epitopes are adaptively acquired by T cells differentiated in the chimaeric condition.

I-J has been defined as a locus mapped in the murine major histocompatibility complex (MHC) which encodes serological markers found primarily on the surface of suppressor T cells (TS) and soluble suppressor factors (TSF). Recent studies have, however, revealed that there is no such specialized locus within the MHC at the DNA level. As the existence of I-J determinants at the protein level on functional T cells, T-cell clones and hybridomas has been confirmed by several serological and biochemical studies, this contradiction has raised serious arguments in the immunological community concerning the nature, origin and expression of I-J determinants. We have raised a number of monoclonal antibodies against the polymorphic structure of I-J molecules, and have studied the expression of I-J epitopes on T cells derived from irradiated bone marrow chimaeras in which stem cells of different genotype differentiated into T cells under the foreign host MHC environment. The results, presented here, indicate that I-J epitopes are not primarily determined by the MHC genes of the stem cells themselves, but are adaptively acquired by T cells differentiated in the chimaeric condition according to the environmental MHC phenotype. Thus, the serologically detectable I-J epitopes are found to be associated with inducible T-cell receptors recognizing self class II MHC antigens.

Animals↗

Radiation pneumonitis following multi-field radiation therapy.

The mechanisms of radiation pneumonitis have not been established. In a study on multi-field radiation therapy for lung cancer, one patient developed severe radiation pneumonitis even though the target volume was small. Radiation therapy was performed at a dose of 75 Gy in 50 fractions over five weeks. High-density areas conforming to the radiation field were observed by high-resolution CT. They were observed in the irradiated volume at doses under 20 Gy in the contralateral lung as well as in the ipsilateral lung.

Aged↗

Endodermal cyst in the cerebellopontine angle with immunohistochemical reactivity for CA19-9.

We present a rare case of the endodermal cyst in the cerebellopontine angle with positive immunohistochemical reactivity for CA19-9. The patient was a 67-year-old woman with an endodermal cyst in the cerebellopontine angle who presented with progressive gait disturbance. A magnetic resonance image showed a cerebellopontine angle which was low in signal on T1-weighted, and high on T2-weighted image without gadolinium enhancement. The preoperative diagnosis was an epidermoid or arachnoid cyst. The patient underwent surgery. Since the intraoperative histological diagnosis by frozen section was endodermal cyst, total removal of the cyst wall was achieved for preventing recurrence. The postoperative definitive histological diagnosis was endodermal cyst, type A by Wilkins-Odom classification, lined by mucinous epithelium with an immunohistochemical reactivity for CA 19-9 protein and cytokeratin. This is the first reported case of a huge endodermal cyst in the cerebellopontine angle of an elderly woman which exclusively showed a differentiation toward the midgut epithelium. The histological diagnosis during surgery by frozen section should be performed for proper treatment.

Aged↗

Intraluminal irradiation for T2M0 esophageal cancer: effect of patient selection on prognosis.

The contribution of intraluminal irradiation to the prognosis of T2M0 esophageal cancer was examined with reference to patient selection. To determine the effect of patient selection, we used esophagrams to assess the potential difficulty of inserting a tube for intraluminal irradiation in 39 patients who were treated with external irradiation prior to 1982. Twenty-two patients were assessed as likely to have been able to undergo intraluminal irradiation (group 1) while 17 were assessed as unlikely to have been able to undergo the procedure (group 2). Of 36 patients treated after 1983, 19 patients were treated with a combination of intraluminal irradiation and external beam therapy (group 3) and 17 by external irradiation alone (group 4). The median survival times of groups 1, 2, 3, and 4 were 10.8, 6.4, 12.0, and 8.5 months, respectively. The prognosis of patients treated with combination therapy (group 3) was superior to that of those treated before 1982 (groups 1 + 2). However, there was no improvement in the prognosis of T2M0 esophageal cancer treated by radiotherapy after the introduction of intraluminal irradiation, and the difference between the survival curves of patients treated by combination therapy (group 3) and with a wide esophageal lumen (group 1) was not significant. Our study thus showed that the selection of patients according to the insertability of the intraluminal therapy tube affected the prognosis.

Aged↗

Cerebrospinal fluid cytology in immature teratoma of the central nervous system. A case report.

The present case shows the usefulness of cerebrospinal fluid (CSF) cytology in the diagnosis of leptomeningeal dissemination by immature teratoma. The tumor arose in the thoracolumbar spinal cord of a 14-year-old male. The initial histopathologic diagnosis was made on the tumor tissue taken at laminectomy. Postoperatively, CSF cytology revealed epithelial cell clusters, scattered squamous epithelial cells and small bundles of striated muscle fibers in the background of many histiocytes and inflammatory cells. Although these cells showed only slight cytologic atypia, their presence in the subarachnoid space suggested the leptomeningeal spread of well-differentiated portions of the immature teratoma. The postmortem examination revealed the primary tumor in the spinal cord and multiple metastatic nodules in the brain.

Adolescent↗

Autoimmune thyroiditis induced in mice depleted of particular T cell subsets. II. Immunohistochemical studies on the thyroiditis lesion.

The intravenous (i.v.) administration of Lyt-1dull T cells into syngeneic (C57BL/6 x C3H/He)F1 T cell-depleted B cell mice resulted in the induction of typical thyroiditis exhibiting massive cellular infiltration. The present study investigated which types of lymphoid cells infiltrate in the thyroiditis lesion and whether immunohistologic change takes place on epithelial cells of thyroid follicles. Both L3T4+ and Lyt-2+ T cells were found in the lesion, although the frequency of infiltration was higher in the former than in the latter. Thyroiditis was also induced by injection of Lyt-1dull L3T4+ but not of Lyt-1dull Lyt2+ T cells, indicating the critical role of a part of L3T4+ T cell subset (Lyt-1dull L3T4+ T cell subpopulation) in inducing thyroiditis. Only rare Lyt-2+ T cells were seen in such a thyroiditis lesion. Infiltrating T cells were predominantly of L3T4+, and these L3T4+ T cells formed cellular infiltrating lesion together with moderate number of B cells and relatively small number of macrophages. Importantly, class II MHC antigens were detected on epithelial cells of thyroid follicles. Such class II MHC expression was observed in coincidence with the area of cellular infiltration in the thyroid. These results demonstrate that: (1) a part of L3T4+ T cells which is required for the induction of thyroiditis by adoptive cell transfer infiltrates into the inflammatory lesion, (2) the induction of the thyroiditis lesion is formed by these L3T4+ T cells as well as B cells and macrophages, but does not necessarily depend on the participation of Lyt-2+ T cell subset, and (3) the aberrant expression of class II MHC antigens on thyroid epithelial cells coincides with cellular infiltration.

Animals↗