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Biomedical subjects

S Taira

Publications and source records attributed to S Taira.

85 records · Page 5Linked to original sources
PubMed1985

Alloantigen presentation by B cells: two types of alloreactive T cell hybridomas, B cell-reactive and B cell-nonreactive.

T cell-depleted, Sephadex G-10-passed unstimulated splenic B cells from C57BL/6 mice stimulated splenic T cells from CKB mice to produce IL 2 and to proliferate. The stimulatory ability of the unstimulated B cells was eliminated by 4000 rad irradiation of the unstimulated stimulator B cells. LPS-activated B cells could stimulate responder T cells more efficiently than unstimulated B cells. For further analysis of allostimulation by B cells, we established a series of alloreactive T cell hybridomas. Forty-five percent of these alloreactive T cell hybridomas could be stimulated to produce IL 2 by either macrophage-dendritic cells or unstimulated B cells. Fifty-five percent of these alloreactive T cell hybridomas could be stimulated by macrophage-dendritic cells but not by unstimulated B cells. T cell hybridomas that were not reactive with unstimulated B cells were also nonreactive to LPS-activated B cells. Analysis of two representative I-Ab-reactive T cell hybridoma clones, B cell-reactive clone CB-11.4 and B cell-nonreactive clone HTB-9.3, revealed again that the stimulatory ability of unstimulated B cells was sensitive to 4000 rad irradiation in the activation of CB-11.4 clone and that CB-11.4 could be stimulated more efficiently by LPS-activated B cells than by unstimulated B cells, but HTB-9.3 could not be stimulated by LPS-activated B cells. Thus, there may be two distinct types of T cells in the alloreaction: B-cell-reactive and B cell-nonreactive.

Animals↗
PubMed1984

[Detection of early pregnancy factor in the sera of conceived women before nidation].

In order to apply the early pregnancy factor (EPF) to early diagnosis of fertilization, the establishment of optimal conditions for assay of EPF was attempted, and then EPF in the sera of contracepted and conceived women 4 to 6 days after ovulation were measured. For assay of EPF, 0.25 ml of 1:2 step diluted anti-human lymphocyte serum (ALS), 0.05ml of guinea pig serum as complement and 0.1ml of lymphocytes suspension (1 X 10(7)/ml) pretreated with test serum were mixed and then incubated at 37 degrees C for 90 min. To this mixture 0.1ml of sheep red blood cell suspension (2 X 10(9)/ml) was added and the rosette formation was counted after centrifugation. The rosette inhibition titer (RIT) was expressed as reciprocal of ALS dilutions which resulted in less than 75% of rosette formation as compared with the control. RITs of the conceived women who were assayed on the 5 th day after ovulation were in the range from 16 to 32 X 10(3), while that of the control contraceptive women who were assayed on the same day was in the range from 2 to 4 X 10(3). The sterile women who received AIH but failed to conceive all showed less than 4 X 10(3) as RIT. These results suggest that the assay of EPF is valuable in detecting the early stage of fertilization and possibly may help to differentiate the impairment of embryo implantation from non-fertilization of the ovum as a cause of sterility.

Chaperonin 10↗
PubMed1982

Fetal heart rate accelerations and late decelerations during the course of intrauterine death in chronically catheterized rhesus monkeys.

The appearance of late decelerations and the disappearance of accelerations in the fetal heart rate were observed during the days that preceded intrauterine fetal death in nine chronically instrumented rhesus monkeys. All nine animals had recovered satisfactorily from the initial surgical procedure, as evidenced by normal biophysical and biochemical parameters. After recovery, all the fetuses had shown accelerations and no late decelerations with spontaneous uterine contractions. The mean duration of the preparations was 16.1 days. The duration of the preterminal observation period varied from 3 to 13 days, during which time no experiments were performed. The fetuses died during labor at a mean gestational age of 143 days. Late decelerations were the first sign of fetal deterioration and occurred with a slight but significant decrease in fetal PaO2 without changes in pH, whereas accelerations in fetal heart rate were still present. The loss of accelerations in fetal heart rate was a later phenomenon and was associated with significant reductions in fetal pH and PaO2.

Animals↗
PubMedDate not supplied

A case of ruptured mesenchymal chondrosarcoma of the pancreas.

A 25-year-old woman who underwent surgical removal of a right frontal meningeal mesenchymal chondrosarcoma in 1980 manifested abdominal pain and progressive anemia after a traffic accident in April 1997. CT disclosed a well-enhanced solid mass 2.5 cm in diameter with internal calcific deposits at the tail of the pancreas and a surrounding hematoma of 5.5 cm in diameter. Surgical resection revealed a ruptured metastatic mesenchymal chondrosarcoma of the pancreas.

Adult↗
PubMedDate not supplied

MR imaging of olfactory bulbs and tracts.

Olfactory bulbs are easily detected on coronal T1-weighted MR images. They are situated almost symmetrically opposite either side of the lower end of the olfactory sulci, and, on sagittal images, they are observed as thin soft-tissue bands immediately beneath the frontal lobe base. On axial images they are shown as oval, paramedian structures of intermediate intensity. Visualization of the olfactory tract, however, is not always possible. Our study reveals that, on axial images, detection of the olfactory bulb depends on technical factors; we recommend a 256 x 256 matrix, a 3-mm-thick slice, and less than a 0.6-mm gap. Despite the lack of complete visualization of olfactory bulbs and tracts, MR may be effective in demonstrating diseases of these entities.

Humans↗
PubMedDate not supplied

MR of acoustic neuromas--relationship to cranial nerves.

In this report, the relationship of acoustic neuromas to the adjacent cranial nerves is discussed. On T1-weighted images, the trigeminal nerve was detected in all 13 cases. Mild to marked compression of these nerves by the tumors was observed in eight cases. The extent of compression did not always correspond to the clinical symptoms. In four cases with a maximum tumor diameter of 2 cm or less, the 7th and 8th cranial nerves were identified. There was no facial palsy in these patients. Two patients with a tumor diameter of more than 2 cm also had no facial palsy. All patients, including those with small tumors, complained of hearing loss and/or tinnitus. While MR imaging has some limitations, it is an effective imaging modality for showing the relationship between tumors and nerves.

Adult↗