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T Sumida

Publications and source records attributed to T Sumida.

At least 181 records · Page 10Linked to original sources
PubMed1986

[Intervillous blood-gas status, especially oxygenation during cesarean section].

Intervillous (IV), arterial (MA), and umbilical venous (UV) and arterial (UA) blood-gas values were measured in 36 healthy pregnant women. The patients were divided into three equal groups and underwent elective cesarean sections under spinal block. Oxygen was administered through a nasal cannula (group OL) or a mask (group OH), through group RA received no oxygen inhalation. Mean MAPO2 in each group was 102.0, 213.9 and 482.4 mmHg, respectively. Intervillous PO2 (Mean +/- SD mmHg) was 49.0 +/- 7.1 in group RA, 63.1 +/- 14.5 in group OL, 84.6 +/- 25.2 in group OH, oxygen saturation (%) was 83.2 +/- 6.0, 89.6 +/- 5.5 and 94.3 +/- 2.6, respectively, and oxygen content (CO2: ml/dl) was 12.7 +/- 0.9, 13.7 +/- 1.0 and 14.4 +/- 0.5, severely. There were significant differences in the intervillous oxygen values among the three groups. The intervillous acid-base value in group RA (pH: 7.389 +/- 0.013, PCO2: 33.9 +/- 2.3 mmHg and BD: 4.4 +/- 0.9 m mol/l) showed no significant differences from those of the other groups. Mean UVCO2 was somewhat greater than mean IVCO2 in any group due to the relatively higher oxygen affinity of fetal blood. Both IV and UVPO2 were not so elevated with oxygen inhalation and this was assumed to be due to characteristics of the oxyhemoglobin dissociation curve. The other results produce reliable evidence that placental circulation is not affected by maternal hyperoxia and that an increase in (IV-UA)PO2 facilitates oxygen transfer to the fetus.

Carbon Dioxide↗
PubMed1985

Novel mechanisms of specific suppression of anti-hapten antibody response mediated by monoclonal anti-carrier antibody.

The cellular mechanisms of the antibody-induced suppression of immune responses were analyzed in the keyhole limpet hemocyanin (KLH) system. Some of the monoclonal anti-KLH antibodies, like KLH-specific suppressor T cell factor (KLH-TsF), were demonstrated to suppress the anti-2,4-dinitrophenyl IgG but not IgM plaque-forming cell responses in a KLH-specific and H-2-restricted manner. The anti-KLH antibodies with suppressive activity reacted with, and in turn, stimulated the suppressor hybridoma (34S-281) with the anti-idiotypic receptor complementary to the idiotypic KLH-TsF of the inducer type. Moreover, because the suppressive activity of the anti-KLH antibody was completely abolished by the treatment of responding spleen cells with anti-Lyt-2 and complement, it was apparent that the suppressive antibody activated suppressor T cell pathways. The isotype or affinity of antibodies is not related to the suppressive activity, because suppressive and nonsuppressive antibodies possess a similar affinity belonging to the same Ig isotypes. It also has been demonstrated that the Fc portion is not the functional site, because the F(ab')2 fragment still has the activity. The antibody specificity is found to be important for determining whether the antibody is suppressive or not. In fact, anti-KLH 26, but not other antibodies without activity, recognizes the particular KLH epitope seen by KLH-TsF, and exclusively interacts with the anti-idiotypic suppressor T cells. Thus, the anti-idiotypic suppressor T cell receives signals both from the suppressive anti-KLH antibody and from KLH-TsF, and transmits the antibody-induced suppressor signals to the effector-suppressor pathway. The size of the repertoire of anti-idiotypic suppressor T cells involved in the suppression seems to be very limited, because only four out of 120 monoclonal anti-KLH antibodies were found to have suppressor activity. The possible mechanisms of the cell interaction mediated by the suppressive antibody are discussed.

Animals↗
PubMed1984

Activation of acceptor-suppressor hybridoma with antigen-specific suppressor T cell factor of two-chain type: requirement of the antigen- and the I-J-restricting specificity.

The molecular mechanisms of activation of immunoregulatory T cells were characterized by using two complementary suppressor T cell hybridoma systems: the KLH-specific monoclonal suppressor factor (KLH-TsF), and the inducible acceptor-suppressor hybridoma line with anti-idiotypic receptor for KLH-TsF. It was demonstrated that the identity of the KLH specificity and genetic specificity was required for the TsF-acceptor interaction. These specificities were found to be mediated by the two polypeptide chains of TsF: KLH-binding, Ct-bearing heavy chain and I-J+ light chain. These two chains were essential for stimulation of the acceptor hybridoma. The results were also confirmed by the findings that the mixture of the 11S and 13S mRNA translation products reconstituted the active TsF to stimulate the acceptor hybridoma. Furthermore, the genetic restriction observed was found to be mediated by the I-J+ light chain and to be governed by the gene linked to the H-2 complex but not to the Igh genes. The gene controlling the restriction specificity was strongly suggested to be in the intra-H-2 complex, but not outside of the H-2 complex.

Animals↗
PubMed1984

[The influence of maternal oxygen inhalation for 30 to 60 minutes on fetal oxygenation].

Healthy parturients with uterine displacement received oxygen inhalation before and during spinal anesthesia for elective cesarean section. Oxygen was administered through a mask (group OH2 : 20 cases) or via a nasal cannula (group OH1: 20 cases) for 33 to 69 minutes. All patients were in the right lateral position prior to spinal block and were in the left tilt after the anesthesia. The fetal blood-gas values were relatively evaluated among the OH2, OH1 and OH groups which received oxygen via a cannula for 9 to 17 minutes. The maternal artery PO2 values for the OH2 group (the mean: 491.7 +/- 61.4mmHg) were significantly higher than those for the OH1 and OH groups (244.5 +/- 28.0 and 225.0 +/- 62.9mmHg, respectively). The umbilical vein PO2 (46.1 +/- 7.5mmHg) and SO2 (87.6 +/- 6.3%) of the OH2 group were also significantly greater than those of the other groups (PO2: 36.1 +/- 4.1mmHg, SO2: 77.3 +/- 6.0% in the OH1 group and PO2: 37.5 +/- 6.4mmHg, SO2: 77.6 +/- 10. 3% in the OH group, respectively). The Apgar scores and both the maternal and fetal acid-base values for all groups were excellent. The umbilical vein to artery PO2 and SO2 gradients of the OH2 group were significantly greater than those of the other groups. It is emphasized that maternal hyperoxia with uterine displacement improves fetal oxygenation without adversely affecting the fetal acid-base state, even if it is excessive and maintained for 60 minutes.

Acid-Base Equilibrium↗
PubMed1983

Acceptor-suppressor T cell hybridoma with a receptor recognizing antigen-specific suppressor factor.

An acceptor hybridoma with a receptor that recognizes the keyhole limpet hemocyanin (KLH)-specific suppressor T cell factor (KLH-TsF) was established after the fusion of C57BL/6 splenic T cells enriched with KLH-coated petri dishes. The cloned hybridoma (34S-281) could be specifically activated by stimulation with the conventional KLH-TsF or monoclonal KLH-TsF from three different hybridomas in the absence of the relevant antigen (KLH) and it started to produce another factor that suppresses the antibody response against DNP-KLH in a KLH-specific fashion. The KLH specificity of the TsF was required for activation. The new factor was found not to bind the KLH but to be absorbed with the KLH-TsF-producing hybridoma. It is thus strongly suggested that the acceptor site has a complementary structure (antiidiotype) for the KLH-TsF. Moreover, the idiotypic determinant on KLH-TsF was found to have a structure similar to that on some of the anti-KLH antibodies, since the acceptor hybridoma was specifically killed by the conventional anti-KLH antibodies and complement. Drawing on the above results, the idiotype-antiidiotype network in the conventional antigen system is discussed.

Animals↗
PubMed1983

Ultrastructural characteristics of duodenal somatostatinomas. II. Granules and vesicles.

Ultrastructural findings of granules and vesicles appearing in tumor cells of somatostatinoma are reported. Except for D granules, one granule and four kinds of vesicles were discerned. Some tumor cells had granules of the exocrine type which were similar to those of the chief cells of the stomach. Very small clear vesicles (YO and KO) had accumulated mainly in the apical region of the somatostatinoma cells. Both vesicles were round, unit-membrane bounded and clear in the center, each measuring about 90 and 30 nm in diameter. The cored vesicles normally seen in the sympathetic system were revealed. Doughnut vesicles characterized by double contour membranes were detected together with the cored vesicles. A mixture of exocrine cells of the chief cell-type in the paraneuroma has not been previously reported. And we have as yet very little information as to the doughnut vesicle.

Adenoma, Islet Cell↗
PubMed1982

A breast carcinoid tumor with special reference to ultrastructural study.

A case of a carcinoid tumor of the left breast of an 83-year-old male is reported. On light microscopy the tumor showed the classical pattern of a carcinoid tumor. Neurosecretory granules were verified ultrastructurally, membrane-bound, about 180 nm in diameter, and possessing electron-dense contents. Some tumor cells had long slender cytoprocesses with small clear round granules other than neurosecretory ones.

Aged↗
PubMed1980

Ultrastructural studies of a thymic carcinoid tumor.

A case of a thymic carcinoid tumor is presented. The tumor was a mass measuring 7 by 6 by 5 cm in size. Microscopically, the tumor was composed of a mixture of round, cytoplasm-rich cells in addition to the predominantly spindle-shaped cells. The ultrastructural observation showed many secretory granules, about 120 mmu in size, in almost every cell of the tumor. In the cytoplasm many microfilaments were seen, in places forming large nodules and bundles. Centrioles were often observed in the tumor cells. Sometimes three or even more centrioles were seen in a single cell.

Aged↗
PubMed1979

Somatostatinoma of the duodenum.

An adenocarcinoma of the second portion of the duodenum in a 26-year-old male is presented. The patient was suffering from pain in the epigastrium. Immunofluorescent studies revealed that it consisted almost exclusively of cells with a distincly positive somatostatin-like immunoreactivity. Ultrastructurally, the cytoplasm of the tumor cells had numerous large round granules (about 400 micrometers) with variable electron density. Most of these cells closely resembled the D cells normally seen in the duodenum and the islets of the pancreas, although a few argyrophil cells could be demonstrated by light microscopy. Radioimmunoassay of extracts of the tumor revealed a large amount of somatostatin (2260 pg/mg); substance P and VIP were detected also. Somatostatinoma has been known to occur in the pancreas, but this seems to be the first somatostatinoma found in the intestine.

Adenocarcinoma↗
PubMed1979

Ultrastructure of mesodermal mixed tumor of the uterus.

A case of mesodermal mixed tumor arising in the uterus of a 57-year-old woman is presented. The tumor was a mixture of adenocarcinoma with occasional squamous metaplasia, stromal sarcoma, myxosarcoma and chondrosarcoma. Light and electron microscopic examinations of the tumor revealed close transition between stromal sarcomatous component and each of other sarcomatous and carcinomatous component. The histogenesis of mixed mesodermal tumor was discussed and it was concluded that the tumor might be derived from endometrial stromal cell which possessed the pluripotency to differentiate toward various epithelial and mesenchymal tissues including the heterologous mesenchymal tissue.

Adenocarcinoma↗
PubMed1978

Norepinephrine-producing tumors of bilateral breasts: a case report.

There was a tumor in the left breast which was suspected to be carcinoid tumor at excisional biopsy. Autopsy revealed the same tumor in the right nipple. In the cells of the bilateral tumors a number of argylophil granules were diffusely demonstrated and the neurosecretory ones were verified electronmicroscopically. In the urine of the patient a moderate amount of norepinephrine was excreted. It was presumed that the norepinephrine might have been produced from the breasts. In the literature reviewed, the case of breast carcinoid has not been reported previously.

Aged↗