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T Kotani

Publications and source records attributed to T Kotani.

At least 163 records · Page 9Linked to original sources
PubMed1992

Diagnostic usefulness of dipeptidyl aminopeptidase IV monoclonal antibody in paraffin-embedded thyroid follicular tumours.

Monoclonal antibodies to dipeptidyl aminopeptidase IV (DAP IV, EC 3.4.14.5) were raised and selectively applied to paraffin-embedded sections of thyroid carcinoma. Five monoclonal antibodies were found to stain paraffin sections of thyroid carcinomas. Using one of these antibodies (44-4), we studied retrospectively aberrant expression of DAP IV in thyroid carcinoma to determine whether immunohistochemical staining with DAP IV antibody is useful in pathological diagnosis. In almost all cases of thyroid follicular and papillary carcinoma, tumour cells were positive (99.0 per cent) with DAP IV, whereas the cases of follicular adenoma showed a low incidence (27.1 per cent) of positive staining. Follicular adenoma with incomplete capsular invasion had a higher positive incidence (50 per cent) than follicular adenoma without incomplete capsular invasion (9.6 per cent). In positive staining cases previously diagnosed as benign tumours, 11 benign cases reacting positively with DAP IV were rediagnosed as carcinoma after re-examination of more thyroid paraffin block sections or serial sections. These findings suggest that DAP IV monoclonal antibody is very useful in distinguishing thyroid follicular carcinoma from follicular adenoma.

Adenoma↗
PubMed1992

Improved PCO2 monitoring during high frequency jet ventilation.

During high frequency jet ventilation (HFJV), it has been shown that Pa(CO)(2) can be predicted by capnography when the frequency was temporarily reduced to obtain a steady expiratory CO(2) tension (P et(CO)(2)). The influence of the sampling site of expiratory gas in the airway and the driving pressure of the ventilator on the difference between Pa(CO)(2) and P et(CO)(2) was investigated in ten adult patients who underwent general anesthesia. During HFJV (frequency: 100 bpm, inspiratory duty cycle; 30%), its frequency was temporarily reduced to 10 bpm in twelve different condition; i.e., 3 different driving pressures (Pd; 20, 30, and 40 psi) at 4 different sampling sites (d; 0, 2, 5, and 10 cm in the endotracheal tube). Both P et(CO)(2) and Pa(CO)(2) were measured simultaneously, and their difference was evaluated by using Student's t-test. The difference between Pa(CO)(2) and Pmax(CO)(2) (the maximum P(CO)(2) value in the airway during exhalation) was minimal, when Pd was greater than 30 psi, and d was greater than 5 cm. The present study suggests that better prediction of Pa(CO)(2) can be done by P et(CO)(2) during HFJV, when d and Pd were set as large as possible to obtain stable expiratory P(CO)(2) curve.

Journal Article↗
PubMed1992

Replication of porcine cytomegalovirus in the 19-PFT cell line.

Replication of porcine cytomegalovirus was examined in fibroblast- and epithelial-like cell lines of the 19-PFT cell line derived from pig fallopian tube. The virus grew well in the fibroblast-like cell line than the epithelial-like cell line. Cytomegalic cytopathic effects of the virus were clearly observed under the microscope after dispersion of the infected cell culture by trypsin-versene and it was demonstrated that cytomegalic cytopathic effects could be used for infectivity titration. Intranuclear inclusions were formed in the infected cells and herpetic virus particles were observed in the nucleus and cytoplasm when infected cells were observed under the transmission electron microscope. Infected cells formed characteristic red plaque.

Animals↗
PubMed1992

Immunohistochemical localization of dipeptidyl aminopeptidase IV in thyroid papillary carcinoma.

The localization of dipeptidyl aminopeptidase IV expressed aberrantly in thyroid carcinoma was studied by immunoelectron microscopy using a monoclonal antibody to the enzyme with special reference to enzyme-histochemical staining of the enzyme. Five thyroid papillary carcinomas were investigated including two lymph-node metastases. All cases showed the dense immunoreaction product on the apical membrane and only traces of the product on lateral membranes, endoplasmic reticulum and nuclear membranes. In one case only, the dense product was observed on basal tubular structures. Analysis, using immunogold labelling on pre-embedded cryosections, revealed that dipeptidyl aminopeptidase IV was localized on the luminal surface of cancer cells. Two different distribution patterns of dipeptidyl aminopeptidase IV activity staining, diffuse and apical patterns, reported previously were thought to be due to different amounts of dipeptidyl aminopeptidase IV in the cytoplasm of cancer cells. This enzyme-histochemical staining method is useful for pathological diagnosis of thyroid tumours and can be applied to clinical materials. The enzyme localization is revealed by the staining pattern.

Adolescent↗
PubMed1992

[The effect of ionized calcium concentration on muscle contraction and on the effect of non-depolarizing neuromuscular blocking agent].

The influence of serum ionized calcium (Ca2+) on the muscle contraction and on the effect of non-depolarizing neuromuscular blocking agent, d-tubocurarine (dTc), was investigated. The isolated phrenic nerve-diaphragma preparation of the rat was stimulated directly and indirectly at 0, 0.4, 0.7, 1.4, 2.5 mM of total calcium concentration (Ca2+: 0, 0.39, 0.52, 1.12, 2.32 mM, respectively). With indirect stimulation, no contraction was observed from 0 to 0.4 mM of calcium, but the twitch tension returned to 100 percent of control at over 0.7 mM of calcium. However, with direct stimulation, the twitch tension was obtained up to 100 percent of control independent of Ca2+ concentration. The ED50 of dTc was correlated well with the serum Ca2+. These findings suggest that the decrease of serum Ca2+ concentration interferes with the muscle contraction and potentiates the effect of dTc. We speculate that the site of its action may be primarily prejunctional.

Animals↗
PubMed1991

Expression of dipeptidyl aminopeptidase IV activity in thyroid carcinoma.

Dipeptidyl aminopeptidase IV activity staining was performed in various thyroid tissues to evaluate this enzyme activity as a thyroid tumor marker. A total of 195 thyroid tissues were tested for their enzyme activity expression. All papillary and follicular carcinomas, 40 cases and 3 cases, respectively, showed enzyme activity, although two other carcinomas, one medullary and one anaplastic, were not stained. Follicular adenoma expressed enzyme activity in 4 of 26 cases. Fifty-two cases with adenomatous goiter, 54 with Graves' disease and 13 with chronic thyroiditis were judged to be negative. Five normal thyroids expressed no activity except for occasional positive staining of capillary endothelia. These data suggest that dipeptidyl aminopeptidase IV activity staining is very useful for pathological diagnosis of thyroid tumors.

Dipeptidyl Peptidase 4↗
PubMed1991

Capsular polysaccharide of a slime-forming Lactococcus lactis ssp. cremoris LAPT 3001 isolated from Swedish fermented milk 'långfil'.

Slime-forming Lactococcus lactis ssp. cremoris strain LAPT 3001 isolated from Swedish ropy sour milk 'långfil' was investigated for the chemical nature of its capsule. The capsular material purified by gel filtration chromatography and ion-exchange chromatography consisted of rhamnose, glucose, galactose, glycerol and phosphorus. It is most likely a deacylated lipoteichoic acid.

Chromatography, Gel↗
PubMed1991

Dipeptidyl aminopeptidase IV staining of cytologic preparations to distinguish benign from malignant thyroid diseases.

Staining for dipeptidyl aminopeptidase IV (DAP IV [EC: 3.4.14.5]) activity was applied to aspiration biopsy specimens or imprint preparations of surgical biopsy specimens from thyroid tumors. Material was obtained from 55 patients with histologically proven thyroid diseases: 9 with papillary carcinoma, 5 with follicular carcinoma, 11 with follicular adenoma, 13 with adenomatous goiter, 8 with Hashimoto's thyroiditis, and 9 with other benign conditions. Most tumor cells, follicular lumina in cell clusters, and intranuclear inclusions were strongly positive for DAP IV in all examples of papillary or follicular carcinoma. In contrast, only a few epithelial cells were labeled for DAP IV in follicular adenoma and adenomatous goiter. Some Hürthle cells in Hashimoto's thyroiditis also were positive for DAP IV. When a DAP IV scoring system based on the percentage of positive cells and staining intensity was used, all benign tissues except one (from a follicular adenoma) were found to have extremely low scores. These results indicate that staining for DAP IV activity is a simple but useful tool to aid in distinguishing benign from malignant thyroid neoplasms.

Adenocarcinoma↗
PubMed1991

[A case of postpartum fever caused by Mycoplasma hominis infection].

A 26-year-old housewife was admitted to our hospital with a history of high fever after previous cesarean delivery. She had premature rupture of the membrane on the 41st week of pregnancy and the amniotic fluid was found to be cloudy on the fourth day after rupture. Therefore, cesarean delivery was performed. On the first day of operation, her body temperature increased up to 38 degrees C in spite of the treatment with Latamoxef (LMOX), 3 g/day. A sample of intrauterine material yielded M. hominis in pure culture. After administration of Minocycline (MINO) with antimycoplasmal activity, the clinical symptoms improved by the 11th day of operation. Sera obtained after the infection showed antibodies to M. hominis in ELISA study. These results suggested that the cause of this postpartum fever was M. hominis infection.

Adult↗
PubMed1991

[Detection of immature granulocytes and atypical and/or abnormal lymphocytes using scatterplots of Coulter STKS].

Scatterplots of the Coulter STKS were studied in order to make better analyses of morphological abnormality of leukocytes. The analytical pattern of a sample failed to completely prevent blood coagulation, especially platelet aggregation, showed the poor separation between lymphocyte and neutrophil populations. On the scatterplot, a small population was occasionally observed in the lower area of normal lymphocyte population with elevation of room temperature, being thought an artificial population. When atypical and/or abnormal lymphocytes increased, the pattern was characterized by the distribution of large lymphoid cells spreading over monocyte population area. The characteristics became clear in proportion to the percentage of large lymphoid cells. To detect immature granulocytes, we introduced a criterion originated in our laboratory. Using the detection criterion, we could obtain the satisfactory results with sensitivity of 85%, specificity of 93%, efficiency of 91% and coefficient correlation (r) of 0.73. It is concluded that the pattern analysis and the detection criterion are useful in the experiments using routine laboratory samples and valuable in clinical implication.

Autoanalysis↗
PubMed1990

Experimental murine thyroiditis induced by porcine thyroid peroxidase and its transfer by the antigen-specific T cell line.

Thyroid peroxidase purified from porcine thyroid (pTPO) was found to induce an experimental murine thyroiditis with genetic restriction which was very different from that induced by mouse thyroglobulin (mTg). C57BL/6 and C57BL/10 (both H-2b) were good responders for thyroiditis, whereas A/J (H-2a), BALB/c (H-2d), DBA/2 (H-2d), CBA (H-2k), C3H/He (H-2k), and SJL/J (H-2s) were poor responders. Genetic analyses using congenic or recombinant strains revealed the following results: The H-2-linked gene (probably the I-A subregion) had a weak association with the induction of thyroiditis, and at least one non-H-2-linked gene controlled the development of thyroid lesions; antibody production to pTPO, porcine thyroglobulin (pTg) and mTg did not correlate with the incidence of thyroiditis in any strain. None of the murine thyroid microsome-specific antibodies tested by the indirect immunofluorescent technique was detected. The T cell line specific for pTPO was successfully transferred to produce thyroid lesions in C57BL/6 mice. Thyroiditis appeared 3 days after the transfer of T cell blasts, and a low concentration of anti-pTPO antibodies was detected concurrently. Thyroid lesions remained up to 48 days with almost the same extent of thyroiditis, but anti-pTPO antibodies gradually increased. In the vaccination experiments using either 0.645 C/kg (2500 rad)-irradiated or 0.3% glutaraldehyde-fixed T cell blasts, the induction of thyroid lesions by transfer was strongly suppressed. Glutaraldehyde fixation was more effective than X-irradiation in preventing thyroiditis after the transfer of T cell blasts. Vaccination also suppressed significantly the development of thyroid lesions after pTPO administration.

Animals↗
PubMed1990

Transcellular iodide transport and iodination on the apical plasma membrane by monolayer porcine thyroid cells cultured on collagen-coated filters.

Isolated porcine thyroid follicular cells were cultured on a collagen-coated Millipore filter to form a monolayer. The monolayer could translocate 125I added in the medium beneath the filter (basal medium) into the medium above the monolayer (apical medium) and form an iodide concentration gradient of several-fold. Transcellular iodide pump activity was observed when the cells were cultured with TSH in the basal medium. In the absence of TSH, the translocation of iodide was very slow. The concentration of TSH required to activate the iodide pump was 0.1-0.3 mU/ml. Addition of ClO4- to the basal medium inhibited transcellular transport, whilst addition of ClO4- to the apical medium was much less effective. Constituents labelled with 125I in the apical medium were analysed. The amount of protein-bound 125I measured by acid precipitation was 3-8% of the total radioactivity. The residual radioactivity was found to be iodide ion by paper chromatography. Further analysis by sodium dodecylsulphate-polyacrylamide gel electrophoresis revealed that most of the 125I-labelled protein was at the position of bovine serum albumin which had been added to the culture medium. The monolayer culture of cells on collagen-coated filter would be a useful experimental system for analysing thyroid cell functions for which the cell polarity is essential.

Animals↗
PubMed1990

[Thyroid peroxidase].

Thyroid Peroxidase (TPO) is a key enzyme in the synthesis of thyroid hormone and is a major thyroid microsomal antigen corresponding to anti-microsomal autoantibodies in thyroid autoimmune diseases. We studied the autoantigenicity, thyroiditogenicity and gene structure of TPO. In micro-ELISA using human TPO as a target, all sera from patients with anti-microsomal antibodies contained IgG class of antibodies to TPO and some sera had IgM class of antibodies. The competitive inhibition test revealed that TPO is the major thyroid microsomal antigen. Experimental murine thyroiditis was successfully induced by the immunization of porcine TPO. Susceptibility of thyroiditis in each strain was very different from that of thyroiditis induced by thyroglobulin. T-cell line specific for porcine TPO could mediate thyroid lesions. Two kinds of full length cDNAs to human TPO were isolated from cDNA library which was constructed from mRNA purified from thyroid with Graves' disease. The longer one consisted of 3,048 nucleotides and its open-reading-frame was likely to encode 933 amino acids. The shorter one lacked 171 nucleotides at the middle portion of the longer one. The structure-gene for human TPO was located on 2q and consisted of 17 exons. One hundred and seventy-one nucleotides deleted in the shorter cDNA exactly corresponded to the 10th exon.

Animals↗
PubMed1989

Stable high level expression of human thyroid peroxidase in cultured Chinese hamster ovary cells.

An expression plasmid containing both human thyroid peroxidase and mouse dihydrofolate reductase cDNAs was transfected into chinese hamster ovary cells. The stably transformed cells constitutively expressed immunoreactive thyroid peroxidase on the cell surface. These cells were further used to establish a subline producing a large amount of thyroid peroxidase by selecting clones resistant to methotrexate. The molecular weight of the expressed thyroid peroxidase was the same as purified human thyroid peroxidase. This expressed protein had peroxidase activity when determined by guaiacol oxidation. Furthermore, the expressed thyroid peroxidase was immunoreactive to sera of patients with autoimmune thyroid disease in which autoantibodies to thyroid peroxidase appeared.

Animals↗