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Biomedical subjects

S Takagi

Publications and source records attributed to S Takagi.

At least 469 records · Page 26Linked to original sources
PubMed1988

[A study of progestin, glucocorticoid binding and glycogen content in rat endometrium before and after implantation: effect of antiprogesterone RU-38486].

Pregnant rats were injected with 3H RU38486 into the uterine cavity on day 2, 4, 5 and 8 of pregnancy. Before implantation, the saturable RU binding increased significantly (day 2 vs. 4; 30.0 +/- 2.3 vs. 640.0 +/- 17.9 dpm/g, p less than 0.001). After implantation, the binding became higher at the nidation site (implantation vs. non-implantation site; 1156.1 +/- 237.1 vs. 595.0 +/- 24.3, p less than 0.001, day 5). The dexamethasone suppressive RU binding, on the other hand, showed no significant increase during day 4, 5 and 8. Daily administration of RU38486 during day 4 and 8 caused failure to implant or to develop normal conceptus. The endometrium in these RU treated animals was stained for tissue glycogen and studied light microscopically. The tissue glycogen content appeared to be markedly decreased in RU treated animals but only at the site of implantation. The decrease was observed in both decidua and trophoblasts but not in myometrium or decidual epithelium. The present results indicate; (1) In rats, endometrial progesterone binding increases prior to implantation. (2) After implantation, the nidation site further increases its saturable progesterone uptake compared to the non-implantation site. (3) When normal process of implantation is inhibited by RU38486 administration, there occurs a decrease in the glycogen synthesis at the nidation site, including decidua and trophoblasts.

Animals↗
PubMed1988

Cytolytic antitumor effector cells in long-term cultures of human tumor-infiltrating lymphocytes in recombinant interleukin 2.

Lymphocytes infiltrating human solid tumors (TIL) and autologous peripheral blood lymphocytes (A-PBL) were cultured with 1000 units/ml of recombinant interleukin 2 (rIL2) in long-term cultures. TIL isolated from 26 primary squamous cell carcinomas of the head and neck expanded better (P less than 0.01) and achieved higher total lytic units of activity against fresh tumor cell targets (P less than 0.05) than A-PBL. TIL obtained from primary hepatocellular carcinomas (n = 7) showed a higher degree of expansion than those from metastatic liver tumors (n = 7). Further, TIL from metastatic tumors of the head and neck, liver, and ovary were delayed up to 50 days in their proliferative response to rIL2. Long-term mass cultures in rIL2 of TIL, A-PBL, or normal PBL were serially monitored for cytotoxicity with different cultured and fresh tumor cell targets and for phenotypic markers of the predominating cell populations. Antitumor cytotoxicity was found in cultures enriched in CD3+Leu19+ and/or CD3-Leu19+ cells. Two-color sorting of such cultures followed by cytotoxicity assays confirmed that the human antitumor effectors expressed either the CD3+Leu19+ or CD3-Leu19+ phenotype. CD3+Leu19- cells had little or no antitumor cytotoxicity. The two types of Leu19+ effector cells were present in low numbers in fresh TIL, A-PBL, or normal PBL; in contrast, in some rIL2-expanded long-term cultures, they represented a majority of proliferating cells. This study identifies for the first time two types of antitumor effector cells in rIL2 cultures of human TIL, one of which may represent activated natural killer cells on the basis of the absence of the CD3 and expression of the Leu19 antigen. These antitumor effector cells mediate non-MHC-restricted cytotoxicity of fresh or cultured tumor cell targets of different histologic types.

Cells, Cultured↗
PubMed1988

Monoclonal antibodies facilitate analyses of ocular development in mice.

To clarify molecular fluctuations during ocular development, we prepared monoclonal antibodies named MAb 111 and MAb 23 which bound differentially to the neural retina, pigmented epithelium, iris and ciliary body. In newborn mice, MAb 111 bound to the pigmented epithelium including the retinal pigmented epithelium, the pigmented layer of the ciliary epithelium and the outer layer of the iris epithelium. MAb 111 also bound to the non-pigmented layer of the ciliary epithelium and the inner layer of the iris epithelium. MAb 23 bound to the neural retina, the pigmented layer of the ciliary epithelium and the outer layer of the iris epithelium. Using these two monoclonal antibodies, we performed immunohistochemical analyses on developing mouse eyes and reached the conclusion that the optic cup has already been determined to differentiate into the retina, ciliary body and iris, on the 15th day of gestation, when the ciliary body and iris are not morphologically demarcated.

Animals↗
PubMed1988

Light-affected ca fluxes in protoplasts from vallisneria mesophyll cells.

In Vallisneria gigantea Graebner mesophyll cells, red light irradiation induces cytoplasmic streaming by decreasing the Ca(2+) concentration in the cytoplasm, while far-red light irradiation inhibits it by increasing the concentration (S Takagi, R Nagai 1985 Plant Cell Physiol 26: 941-951). To examine the effects of light irradiation on Ca(2+) fluxes across the cell membrane, protoplasts are isolated from the mesophyll cells. Changes in Ca(2+) concentration in a solution bathing the protoplasts are monitored by spectrophotometry, using the Ca(2+) -sensitive dye murexide. Red light irradiation induces an increase in Ca(2+) concentration, which means an efflux of Ca(2+) from the protoplasts. Subsequent far-red light irradiation produces a rapid decrease in Ca(2+) concentration down to the dark control level; however, this is not observed in the presence of the Ca(2+) -channel blocker nifedipine. Vanadate inhibits both the streaming and the Ca(2+) efflux induced by red light irradiation. The results suggest that red light and far-red light control Ca(2+) movements across the cell membrane, which in turn regulate the streaming.

Journal Article↗
PubMed1988

Hyperglycemia induced by electrical stimulation of lateral part of dorsal parabrachial nucleus.

Electrical stimulation of the lateral part of the dorsal parabrachial nucleus (PBD) induces hyperglycemia by enhancing glucagon secretion and suppressing insulin secretion in rats. The mechanism of this effect in the light period was examined by use of blockers of the autonomic nervous system. Hexamethonium, a ganglion blocker, and propranolol, a beta-adrenergic blocker, markedly inhibited the hyperglycemic response to stimulation of the lateral part of the PBD (LPBD). In contrast, phenoxybenzamine, an alpha-adrenergic blocker, and atropine methylnitrate, a muscarinic blocker, had no effect. Because previous studies showed that bilateral lesions of the suprachiasmatic nucleus (SCN) eliminated hyperglycemia induced by intracranial injection of 2-deoxy-D-glucose and that blinding largely suppressed the hyperglycemia, the effects of these two treatments on hyperglycemia induced by electrical stimulation of the LPBD were examined. SCN lesions abolished the hyperglycemic response but did not affect the hyperglucagonemic response. Results 4 wk after orbital enucleation were similar to those after SCN lesions. These findings suggest that the SCN and a beta-adrenergic mechanism are involved in the hyperglycemic response to LPBD stimulation.

Animals↗
PubMed1988

Studies on iridoid-related compounds. V. Antitumor activity of iridoid dervs. periodate oxidation products.

In the course of a modification study of iridoid glucosides to investigate their antitumor and antimicrobial activity, we found that about all metaperiodate oxidation products of iridoid glucosides which had no antitumor activity showed potent activity against the leukemia P388 in mice. They were found to be more active than the corresponding aglycones obtained by enzymic hydrolysis of iridoid glucosides. Among them, periodate oxidation product of sweroside showed the most potent activity, of which the maximum total/control (T/C) value was 198% at 200 mg/kg.

Animals↗
PubMed1988

Characterization of novel anti-tumor effector cells in long-term cultures of human tumor-infiltrating lymphocytes.

TIL were isolated from human solid tumors and cultured in rIL 2. Long-term TIL lines from primary tumors showed a shorter lag period, better expansion, and higher anti-tumor activity in vitro than those from metastatic tumors. The anti-tumor effector cells in TIL and A-PBL cultures had CD3+ Leu 19+ and CD3- Leu19+ phenotypes and morphology consistent with LGL/LAK cells. These cells mediated lysis of both autologous and allogeneic fresh tumor cell targets, while CD3+ Leu19- cells had little or no antitumor cytotoxicity.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1988

Differential effects of dibutyryl cyclic adenosine monophosphate and simple sugars on NK and LAK activities suggesting differences of their cytotoxic mechanism.

The increase of intracellular cyclic AMP levels suppresses the cytotoxic activities of lymphocytes and monosaccharides interfere with cell to cell and cell to cytokine interactions, and these effects on natural killer (NK)/antibody-dependent cell-mediated cytotoxicity (ADCC) and lymphokine activated killer (LAK) activities were examined. Dibutyryl cyclic AMP markedly suppressed NK, IL-2-augmented NK and ADCC activities in a dose-dependent manner but not previously induced LAK activity. Induction of LAK was inhibited. Dibutyryl cyclic GMP had no effect. Addition of mannose 6-phosphate and galactose 6-phosphate strongly inhibited NK and ADCC activities, but not LAK activity. These results suggest that the lytic mechanism for NK and ADCC activity is different from that of LAK activity.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1988

[A case of clivus chordoma showing hemorrhage in the posterior fossa].

We are reporting a rare case of clivus chordoma with fatal hemorrhage in the posterior fossa. A 38-year-old woman afflicted with sudden onset of severe headache and vomiting. On neurological examination, she was mildly lethargic. She had slight dysarthria and nystagmus, but no cranial nerve abnormalities. Craniogram revealed erosive changes in the right petrous bone. CT scan showed a massive intracerebellar hemorrhage and isodense mass in the sphenoid sinus, which were not enhanced by contrast medium. She became comatose and died 3 days later. No operation was performed. Autopsy revealed massive hemorrhage in the posterior fossa and yellowish, gelatinous tumor extending from the right clivus to the sphenoid sinus. Histological examination showed a chordoma. This case demonstrates that the hemorrhage associated with brain tumor, especially in posterior fossa, produces a significant sudden elevation of intracranial pressure and leads clinically to a rapid loss of consciousness and death soon after the onset.

Adult↗
PubMed1988

Ureteral stenosis secondary to common iliac aneurysm: a case report and review of the literature in Japan.

A case of right ureteral obstruction secondary to right common iliac aneurysm presenting as right hydronephrosis is reported and the literature is reviewed. A 66-year-old man was admitted to our hospital with lower abdominal pain and was treated by bypass operation with artificial vessel and uretero-ureterostomy of right ureter under the diagnosis of right ureteral stenosis secondary to right iliac aneurysm. Histological examination showed arteriosclerotic aneurysm and a fibrillary inflammatory change in peri-ureteral tissue without any hemosiderin-laden macrophages. Intravenous pyelography showed improvement of right hydronephrosis 45 days after operation. To date 11 cases including our case have been reported in Japan, 10 in males and the other in a female. Initial symptoms were either lumbago or an abdominal mass with palpitation in many cases. The treatment was by resection of aneurysm with bypass grafting or ureterolysis.

Aged↗
PubMed1988

[Arm rotation during abduction of the shoulder in the scapular plane].

The arm rotation during abduction of the shoulder in the scapular plane was investigated in 11 volunteers. The degree and direction of the arm rotation were measured using five potentiometers, and were analysed by a computer system. In eight volunteers, the arm always rotated externally (1.5 degrees-4.9 degrees of rotation for each 10 degrees of abduction); in one volunteer it rotated internally (0.9 degree of rotation for each 10 degrees of abduction); and in the two remaining volunteers it rotated without showing a constant tendency during the abduction. The degree of arm rotation was correlated to the tilting angle of the acromial articular surface which was measured radiographically. A tendency of external rotation of the arm is suggested to occur during abduction in the scapular plane along with the decrease of the tilting angle of the acromial articular surface.

Adult↗