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Biomedical subjects

T Kadota

Publications and source records attributed to T Kadota.

At least 145 records · Page 8Linked to original sources

Comparison of therapeutic usefulness of vitamin D3 analogs on osteoporosis caused by ovariectomy in rats.

Ovariectomy induced a remarkable reduction in the ash content of the femur and histologically a disappearance of the trabecular bone in tibial metaphysis accompanying the decrease of serum calcium level and urinary calcium excretion in young immature rats. Treatment with 1 alpha-hydroxyvitamin D3, 1,25-dihydroxyvitamin D3 and 1,24R-dihydroxyvitamin D3 for 3 months from 7 to 9 months after the ovariectomy dose-dependently increased serum and urinary calcium, bone ash, and histologically partly improved a loss of trabeculae. The 24R,25-dihydroxyvitamin D3 doses, on the other hand, produced no therapeutic effect on the bone disorders in ovariectomized rats, except for the slight effect on the increasing activity of serum calcium.

Animals↗

[Comparison of immunochemotherapy and chemotherapy of stage IV gastric carcinoma].

Fifty-eight patients with stage IV gastric carcinoma were studied for the 24-month survival rate after receiving immunochemotherapy (Mitomycin-C + FT 207 + OK 432 + PSK, 29 cases) and chemotherapy Mitomycin-C + FT 207, 29 cases). There were no differences in the background factors influencing survival time between the two groups. The survival rate of the immunochemotherapy group was higher than, that of chemotherapy group throughout the observation period, in addition to statistical significance in some periods. The 50% survival rate was 10 months, in the chemotherapy group and 18 months in immunochemotherapy group. The difference in survival between the nonresected cases with immunochemotherapy and the resected cases with chemotherapy was smaller than that between nonresected cases and resected cases of the chemotherapy or immunochemotherapy group. These results suggested that possibility that immunochemotherapy prolonged the survival of patients with stage IV gastric carcinoma.

Adult↗

[Pituitary hormone responses to exercise at high altitudes].

The secretory responses of the anterior pituitary hormone to physiological stress were studied in healthy male volunteers. Measurements of blood LH, FSH, Prolactin, GH, ACTH, lactate, pyruvate and hematocrit were made from blood samples taken at rest, after 15 minutes at sea level, and at an altitude of 4000 m and 5500 m modulated in a climate-controlled room. The results are summarized as follows: Blood levels of Prolactin and ACTH were increased after exercise at a high altitude. Blood levels of LH and FSH after exercise at each altitude were not significantly different from those at rest. Blood GH level was increased after exercise at any altitude. Blood levels of lactate and pyruvate were increased after exercise at any altitude. These results suggest that the secretory response of the anterior pituitary hormone to physiological stress is prominent in Prolactin, GH and ACTH but not in FSH and LH.

Adrenocorticotropic Hormone↗

Quantification by selected ion monitoring of pipecolic acid, proline, gamma-aminobutyric acid and glycine in rat brain.

A procedure for the simultaneous analysis of brain pipecolic acid, proline, gamma-aminobutyric acid and glycine--amino acids with potent inhibitory actions on the central nervous system--was developed. The identification and quantification of the amino acids were performed with a gas chromatographic--mass spectrometric--computer system using deuterium-labelled amino acids as the internal standards. After separation of the amino acids by high-performance liquid chromatography, the methyl ester heptafluorobutyryl derivatives were prepared. The lower limit of quantification for this method is at the picomole level. The usefulness of this chromatographic procedure has been demonstrated by measurement of trace amounts of pipecolic acid in rat brain.

Animals↗

Mating pheromone-induced alteration of cell surface proteins in the heterobasidiomycetous yeast Tremella mesenterica.

Mating pheromone-induced alteration of the cell surface proteins of haploid cells, presumed to play crucial roles in the specific cell-cell interactions during sexual conjugation of Tremella mesenterica , was investigated. Exposed surface proteins were revealed by lactoperoxidase-catalyzed iodination in combination with polyacrylamide gel electrophoresis and autoradiography. From comparison of the molecular species of 125I-labeled surface proteins of the vegetative and the gamete (mating pheromone-treated) cells of the two compatible mating types (ab and AB), it was suggested that a striking change in cell surface structure occurs during the differentiation; although labeled protein species of the vegetative cells of the two mating types were indistinguishable, several new species, both mating type specific and nonspecific, appeared in the gamete cells. Turnover of the labeled proteins of the vegetative cells was negligible, whereas that of the gamete cells was rapid with release of low-molecular-weight labeled proteins in the medium. A role for the labeled surface proteins of the gamete cells in the cell-cell interactions during sexual conjugation was suggested by the following: the surface changes were induced by mating pheromone; the labeled proteins were preferentially localized on the surface of the mating tube; the labeled species appeared sequentially during the differentiation; and mating type-specific species were present in both mating types.

Animals↗

Thin section and freeze-fracture studies on the synapses in the ventral nucleus of the cat medial geniculate body.

Ultrastructure of the synapses in the ventral nucleus of the cat medial geniculate body was examined with freeze-fracture and thin section techniques. Two types of synapses were recognized in this nucleus. One was the asymmetrical type such as the afferent nerve fiber to the principal cell dendrite or to the process of Golgi type 2 cell. The other was the symmetrical type such as the process of Golgi type 2 cell to the principal cell dendrite. These synapses made conglomerate on the principal cell dendrite called the glomerulus, which was ensheathed by thin sheets of the astroglia and easily recognized by freeze-fracturing. A random distribution of intramembrane particles (IMP) and synaptic vesicle attachment sites were found on the presynaptic P-face of both type synapses. Asymmetrical synapses had distinct aggregates of IMP on the postsynaptic E-face and the area of IMP aggregates on this face is often larger than 0.07 micrometer2. Similar aggregates of IMP occurred on the same face of symmetrical synapses. However, the area of IMP aggregates of this type synapses is frequently smaller than 0.05 micrometer2. IMP composing the aggregate on the postsynaptic E-face showed bimodal distribution in size, having peaks at 10 nm and 13 nm in diameter. The ratio of large IMP (13 nm) to the total number of IMP increased as the synaptic contact on the postsynaptic membrane widened in area. Non-synaptic contacts, having a complex of dense materials and neurofilaments at the subjunctional area and being similar to the filamentous contact in the lateral geniculate body, were frequently observed on the dendrite of the principal cell in thin sections. Clusters of IMP were scattered on the dendritic P-face near around the postsynaptic area and may represent the area being attached with dense materials of the contacts.

Afferent Pathways↗

Danazol suppression of gonadal estradiol-17 beta secretion--report of two sibling cases with a complete form of testicular feminization on gonadal ultrastructure and endocrine status.

It has been established that the pathogenesis of a complete form of testicular feminization syndrome (TFM) is due to end-organ unresponsiveness to androgens. In the present study, two sibling cases with TFM have been reported with special reference to the effect of danazol (a derivative of 17 alpha-ethynyltestosterone) on gonadal estradiol-17 beta (E2) secretion in vivo and in vitro. Both patients showed hypergonadotropic-hypergonadism with good response to LH-RH. In one case, peripheral blood E2 levels seemed to fall independently of gonadotropins during danazol administration in vivo. Administrations of danazol to the culture media also inhibited E2 secretion from the cultured monolayered cells of the testes. These results suggest a direct inhibitory effect of danazol on gonadal E2 secretion. However, the feedback mechanisms of hypothalamic-pituitary units to E2 were preserved in both cases. Spermatogeneses were almost undetectable as in immature embryonal testes when using either light or electron microscopies, though spermatogonia were differentiated from Sertoli cells by these techniques. Finally, plasma T and E2 levels in both patients were considerably lower after gonadectomy.

Adult↗

[Intraperitoneal administration of FT-207 for mouse peritonitis carcinomatosa].

The peritoneal surface of the lesion was observed after treatment by scanning electron microscopy to evaluate the anticancer effect of FT-207. FT-207 (1.0 mg/day) was injected intraperitoneally to the DDN mice in which 3 X 10(7) MM2 tumor cells were inoculated the day before treatment. The anticancer effect was examined from 2nd to 7th consecutive day after tumor cell implantation, and the following results were obtained. 1) In the early phase after injection of FT-207, many macrophage-like cells were observed on the peritoneal surface. 2) Each MM2 tumor cell was covered by many macrophage-like cells, and these tumor cells were destroyed. 3) In the late phase after injection of FT-207, tumor cells were hyperplastic on the peritoneal surface, but less prominent than in the control group. 4) Effusion and adhesion in peritonitis carcinomatosa of FT-207 group were less than in the control group.

Animals↗

[Effect of butorphanol tartrate on cross-fostering in rats].

In the preceding study, neonatal deaths were observed when an analgesic, butorphanol tartrate (BT), was administered subcutaneously to female rats during the perinatal and lactating periods. In the present study, cross-fostering using CRJ:CD (Sprague-Dawley) rats was employed to clarify the cause of death. When the litters naturally delivered from dams receiving BT (25 mg/kg/day, s.c.) during the perinatal period were switched among one another within the BT-treated dams or placed with control (saline-treated) dams, the viability of newborns on postpartum day 3 was significantly lowered. Since some of the BT-treated dams were observed to neglect the delivery cares that were fundamental to dams such as removing amnions, umbilical cords and placentas, as well as gathering and lactating to newborns immediately after natural delivery, it was considered that death after cross-fostering was the result of the pups being emaciated before cross-fostering. This finding was supported by the fact that a significant elevation in the viability was revealed when the newborns Cesarean-delivered from BT-treated dams were placed with control or untreated dams. No significant effects of BT were observed on the viability and body weight of newborns at birth and on those of pups from postpartum day 3 through the weaning day.

Analgesics↗

[Evaluation of chemotherapy of breast cancer (2). Clinical evaluation of the blood and tissue concentrations of FT-207 following intrarectal administration].

In order to examine the transfer of antitumor drug in breast cancer after administration of FT-207 suppository, FT and 5-FU concentrations in blood, tumor tissues, normal tissues and axillary lymph nodes were determined respectively. FT and 5-FU concentrations in tumor tissues were higher than those in normal tissues or lymph nodes in every cases, and there was a significant difference between FT and 5-FU concentration in blood and tumor tissues. Blood levels of FT and 5-FU remained quite constant at 16 and 20 hours after administration, respectively. Accordingly, it was suggested that the administration of FT-207 suppository to breast cancer was very effective as an adjuvant chemotherapy.

Breast↗

[Effect of solcoseryl and combined therapy of solcoseryl and FT-207 for mice bearing meth-A tumor].

The effects of a combined chemotherapy of solcoseryl and FT-207 on tumor growth, delayed hypersensitivity and cell population of the spleen were studied using inbred BALB/c mice. Meth-A tumor cells (2 X 10(6] were inoculated into the back of 5 to 6 week old BALB/c male mouse. Animals were divided into three groups: Solcoseryl group, in which 0.04 mg of solcoseryl was injected intravenously three times before inoculation and four times after inoculation; Combined group, in which 1.2 mg of FT-207 and 0.04 mg of solcoseryl were injected intravenously four times after inoculation; FT-207 group, in which 1.2 mg of FT-207 was injected four times after inoculation, with out solcoseryl administration. Following results were obtained: Solcoseryl group showed enhanced immunity and tumor suppression; Decreased immunity due to FT-207 was recovered by administration of solcoseryl but no tumor suppression was observed and, Decreased T-cell population of spleen due to FT-207 was recovered by administration of solcoseryl. These facts suggested that solcoseryl was useful because of making recovery possible from decreased immunity due to chemotherapy.

Actihaemyl↗

[Case of breast cancer associated with Recklinghausen's disease].

Malignant epithelial tumors associated with Recklinghausen disease are very rare. A 32-year-old female with Recklinghausen disease was admitted to our hospital complaining of a 5 X 4 cm left breast mass. A malignant tumor of the breast was diagnosed by mammography, echography and clinical features. Radical mastectomy was performed and pathological examination showed papillotubular adenocarcinoma. Three cases of breast cancer associated with Recklinghausen disease reported in the Japanese literature were reviewed.

Adenocarcinoma↗

[Case of gastrin-producing carcinoid, adenocarcinoma and xanthoma of the stomach].

A rare case with gastrin-producing carcinoid, adenocarcinoma and xanthoma of the stomach is presented. A 69-year-old male underwent total gastrectomy with splenectomy and distal pancreatectomy. The histological type of the carcinoid was poorly differentiated (type D), and argyrophil cell carcinoma. Immunoperoxidase staining of the carcinoid was positive for gastrin and negative for glucagon, somatostatin or insulin. The histological findings of the carcinoma were tub 2, medullary, INF alpha, se, ly 2, v 1, ow(-), aw(-), n 1. Histologically, the xanthoma consisted of foamy macrophages accumulated in the lamina propria.

Adenocarcinoma↗

[The effect of cysteamine on the duodenal defense mechanism in the vagotomized rats--with special reference to the parietal cell vagotomy with CO2-laser].

The parietal cell vagotomy with CO2-Laser defocused beam has been developed and its efficacy was confirmed in cysteamine induced duodenal ulcer in rat. Rats were classified into the truncal, parietal cell and Laser vagotomy groups and control. After cysteamine was administered, the change of the Brunner's gland were examined histologically for each group. Duodenal ulcer was seen and the depletion of the Brunner's glands was observed in all control rats. Duodenal ulcer formation was prevented in all vagotomized rats regardless of the type of vagotomy and the preservation of synthetic activity of the Brunner's gland was noted. However, multiple gastric ulcer was seen in truncal vagotomy group. Laser vagotomy was done very easily and safely. It consumed much less time and prevented duodenal ulcer formation. It prevented the cysteamine induced duodenal ulcer formation in rats by preservation of the Brunner's gland activity.

Animals↗

[Physical dependence liabilities of butorphanol, a narcotic antagonist, and its main metabolites, norbutorphanol and hydroxybutorphanol].

After the intravenous injection of butorphanol or norbutorphanol in rats every 1 hr for 3 days, naloxone-induced body weight loss and withdrawal syndrome were observed to some degree. A slow-released emulsion containing each of the test drugs was injected subcutaneously in guinea-pigs, and naloxone was administered after 2 or 3 days. BT caused little jumping response even at a dose of 600 mg/kg, and the reaction was significantly weaker than that of pentazocine. No jumping responses were recognized in the cases of NB (600 mg/kg). In morphinized rats, the injection of BT or HB caused potent body weight loss, and these rats exhibited withdrawal syndrome which was more potent than that by pentazocine at the same dose. The body weight losses by the injection of NB and pentazocine were to the same degree, and these changes were significantly different from that of the saline control. BT inhibited the adenylate cyclase activity of the rat caudate nuclei, and the effect was weaker than that of pentazocine. NB showed a slight inhibition, and HB had no effect on the activity. These results suggest that the physical dependence liability of butorphanol is less than that of pentazocine, and the potent mu-antagonistic character of butorphanol is based on the liability. NB, a mu-agonist, makes dependence production possible. The ability of HB is negligible.

Animals↗