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Biomedical subjects

T Koike

Publications and source records attributed to T Koike.

At least 595 records · Page 33Linked to original sources
PubMed1991

[Raised polyamines in erythrocytes of DMH administrated rats with colonic cancers and those relationship to tumor volume].

The objective of this study was to assess, in a controlled experimental system, whether the concentrations of polyamines (Pa) in urine or erythrocytes increase during the process of colon carcinogenesis in rats, and whether such changes reflect tumor volume. Colon carcinoma was induced in Sprague-Dawley rats by subcutaneous injection of 1, -2 dimethylhydrazine (DMH). 24-hour urine and blood samples were collected and analysed for their Pa consent, with high pressure liquid chromatographic method. The levels of any Pa derivatives in either urine or erythrocytes at 32 weeks after the administration of DMH were not significantly high compared with the control group at the same week. However, certain increases of Pa in erythrocytes were observed in the levels of putrescine (1.3 times), spermidine (1.3 times), and spermine (1.5 times) respectively compared with the control group and there were high positive correlations between tumor volume and the levels of each Pa derivatives. On the ground of the results, Pa in erythrocytes seems to be the sensitive parameter for tumor volume compared with Pa in urine.

1,2-Dimethylhydrazine↗
PubMed1991

[Surgical treatment of advanced (p-stage III.IV) lung cancer less than 2.0 cm in size].

We treated surgically 567 patients with primary lung cancer from June 1975 to December 1989. There were nine patients with advanced (p-stage III.IV) lung cancer less than 2.0 cm in size. The five year survival rate was 50.8%. The histological diagnosis was adenocarcinoma in 6, squamous cell carcinoma in 3. A curative resection was performed in seven of nine patients. Six patients had one level metastasis of mediastinal lymph node. Three patients in whom relative curative resection was performed at surgery later developed regional recurrence. However, distant metastasis was not evident in all but one of nine patients. In conclusion surgical resection is considered to be significant in patients with advanced (p-stage III.IV) lung cancer less than 2.0 cm in size.

Adenocarcinoma↗
PubMed1990

[Studies on liposomal ferromagnetic particles and a technique of high frequency inductive heating--in vivo studies of rabbits].

The tumor can be more selectively heated by applying of high frequency inductive heating after administration of ferromagnetic particles into a tumor. In order to devise a technique used for the selective hyperthermia of a tumor with high frequency inductive heating, we continued fundamental studies using liposomal ferromagnetic particles (HP-LM), which were prepared as follows: triiron tetoraoxide (Fe3O4) particles were coated with liposomal membrane contained hematoporphyrin with neoplastic affinity. In Vivo Studies of Rabbits: We used high frequency inductive heater (NIHON KOSHUHA CO. LTD. YKN-10), frequency: 400 kHz, out put: 10 kW, coil diameter: 90 mm. VX-2 tumor cells at 1.5 X 10(7) were implanted to the lower thigh of rabbit. When the implanted tumor grew up 3 cm in diameter, A-D group were heated and studied. Group A: In a dose of 200 mg/kg of HP-LM was administered into the femoral artery, Group B: In a dose of 100 mg/kg of Fe3O4 was administered into the femoral artery, Group C: Ligation of femoral artery, Group D: Nonadministrated, and then was immediately heated. Group A: In a dose of 200 mg/kg of HP-LM, with heating for 10 minutes, temperature was elevated 14. 8 degrees C at center of tumor. Group B: In a dose of 100 mg/kg of Fe3O4, with heating for 10 minutes, temperature was elevated 10.6 degrees C at center of tumor. Group C: In a ligation of femoral artery, with heating for 10 minutes, temperature was elevated 6.5 degrees C at center of tumor.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Target cell of leukemic transformation in acute megakaryoblastic leukemia.

Acute megakaryoblastic leukemia (AMkL) is a newly defined acute leukemia in which the differentiation of proliferating blasts is arrested at the megakaryocytic precursor stage. In order to clarify whether a target cell of leukemic transformation in AMkL is a cell committed to megakaryocytic lineage, or a multipotential stem cell, we examined AMkL patients with regard to: a) the presence of myelodyplastic features in residual erythroid and granulocytic cells, b) coexistence of myeloperoxidase (MPO)-positive blasts with megakaryoblasts, and c) the presence of the same chromosomal abnormality in erythroid and granuloid colony-forming cells as seen in megakaryoblasts. Regarding the former two items, results were compared with those from megakaryoblastic crisis of chronic myelocytic leukemia (CML-MkBC) and transient myeloproliferative disorder in Down syndrome (DS-TMD), which are thought to be multipotential stem cell disorders. Among 18 patients with AMkL, three, all complicating myelofibrosis, had marked myelodysplastic changes of erythroid series and/or granulocytic series. In 4 out of 7 patients with CML-MkBC, 5 out of 8 patients with DS-TMD, and 7 out of 18 patients with AMkL, MPO-positive blasts, even though rare, were observed in addition to PPO-positive blasts. All except one of these patients with AMkL also showed complicating myelofibrosis. In one case of AMkL with myelofibrosis, chromosomal analysis of cultured cells of individual colonies revealed that all the analysable metaphases from both CFU-GM and BFU-E had the same chromosomal abnormality as megakaryoblasts. This study has clarified that a considerable proportion of AMkL cases, particularly those with complicating myelofibrosis or showing acute myelofibrosis, arise against the background of a multipotential stem cell disorder, even if blasts are exclusively megakaryocytic in phenotype.

Cell Transformation, Neoplastic↗
PubMed1990

The immunosuppressant FK-506 prevents progression of diabetes in nonobese diabetic mice.

A novel immunosuppressive compound, FK-506, isolated from Streptomyces has potent immunosuppressive activities. To investigate the effect of FK-506 on the course of diabetes in nonobese diabetic (NOD) mice, we gave this drug to these animals, from the age of 8 weeks, intraperitoneally, in doses of 0.1 mg (2.5 mg/kg/day) or 0.01 mg (0.25 mg/kg/day) three times a week. Overt diabetes were observed in 75.5% of control mice by the age of 20 weeks. In contrast, no diabetes occurred in mice given 0.1 mg of FK-506. Sixteen percent of mice treated with 0.01 mg of the drug became diabetic. Administration of this drug prevented the progression of insulitis in NOD mice. The mice given 0.1 mg of FK-506 lost weight, but this was reversible.

Animals↗
PubMed1990

Effect of water sorption and thermal stress on cavity adaptation of dental composites.

The effect of water sorption of composite and thermal stress on the marginal adaptation to the dentin cavity wall was evaluated by measurement of the gap width between composite fillings and the dentin cavity wall. The wall of a cylindrical dentin cavity prepared in the proximal surface of extracted human molars was cleaned with neutralized 0.5 M EDTA and pre-treated with one of three experimental dentin primers [35% hydroxyethyl methacrylate (HEMA), 35% HEMA containing 5% glutaraldehyde, and 35% glyceryl methacrylate]. A light-activated composite (Silux, 3M Co., St. Paul, MN) was used to fill the cavity after application of a bonding agent (Clearfil New Bond, Kuraray Co., Osaka, Japan). The marginal gap width was measured after the specimens were immersed in water and thermal-cycled. The initial contraction gap of the tested bonding systems was closed completely by the water sorption of the composite for six hours, and such a marginal adaptation was not interrupted by 60 thermal cycles between 10 and 45 degrees C. Among the dentin primers tested, only the 35% aqueous solution of glyceryl methacrylate mediated gap-free fillings in all specimens.

Composite Resins↗
PubMed1990

Role of 1,25-dihydroxycholecalciferol in growth-plate cartilage: inhibition of terminal differentiation of chondrocytes in vitro and in vivo.

The effects of vitamin D metabolites on alkaline phosphatase [ALPase; orthophosphoric-monoester phosphohydrolase (alkaline optimum), EC 3.1.3.1] activity, a marker of terminal differentiation, in chondrocyte cultures and growth plates in vivo were examined. In cultures of pelleted rabbit growth-plate chondrocytes, 1,25-dihydroxycholecalciferol (1,25-dihydroxyvitamin D3) increased the contents of DNA and macromolecules containing uronic acid (proteoglycans). It also decreased ALPase activity with an ED50 of less than 1 nM. Other vitamin D3 metabolites, such as 24,25-dihydroxycholecalciferol and 25-hydroxycholecalciferol, had little effect on these biochemical parameters. In rachitic growth plates, the uronic acid content was half that in normal growth plates, whereas ALPase activity was 2.5 times that in normal growth plates. Administration of 1,25-dihydroxycholecalciferol at a low dose (0.1 micrograms per kg of body weight) to rachitic rats increased the uronic acid content 1.4-fold and decreased ALPase activity by 40%. This compound, like 24,25-dihydroxycholecalciferol (10 micrograms per kg of body weight), increased the calcium level of the blood. However, administration of 24,25-dihydroxycholecalciferol had little effect on the uronic acid and ALPase contents in growth plates. These observations suggest that 1,25-dihydroxycholecalciferol is a bioactive form of vitamin D that plays an important role in the control of chondrocyte terminal differentiation.

24,25-Dihydroxyvitamin D 3↗
PubMed1990

The relationship between anti-IgE auto-antibodies and the IgE response to wasp venom during immunotherapy.

During immunotherapy with wasp venom, levels of venom-specific IgE antibodies increase and then fall, whereas the concentration of IgG antibodies rises and then remains at a high level. Successful treatment is therefore associated with both increased concentrations of serum IgG and decreased serum IgE antibodies to venom. In this study we have investigated the possible role of auto-antibodies in inducing the decrease in serum IgE antibody. Levels of auto-anti-IgE were measured by a radioimmunoassay. Anti-IgE auto-antibodies were not generated during immunotherapy and there was no significant difference in the levels of anti-IgE auto-antibodies between patients whose venom-specific IgE antibody levels fell more than fivefold after immunotherapy and those patients in whom IgE antibody levels did not change significantly. We conclude that anti-IgE auto-antibodies do not play a part in IgE suppression induced by immunotherapy.

Autoantibodies↗
PubMed1990

Expression of IgH promoter/enhancer Ly-1 transgene in hematopoietic chimeric mice generated by embryonic stem cell line.

We have produced hematopoietic chimeric mice from an embryonic stem (ES) cell line carring Ly-1 cDNA under the control of IgH promoter and enhancer. Various amounts of serum IgM (5-86% of total IgM) in chimeric mice were of ES origin and 30-60% of IgM-positive B cells from the chimeric mice analyzed were reconstituted from ES cells. Using these chimeric mice, the expression of the Ly-1 transgene on lymphoid tissues was examined by polymerase chain reaction assay with primers specific for the transgene, and by cell sorter analysis. Transcription of the Ly-1 transgene was detected in spleen cells, thymocytes and lymph node cells; however, the expression of the Ly-1 molecule was observed only on lipopolysaccharide (LPS)-stimulated splenic IgM-positive B cells but not on resting splenic B cells. There was no significantly increased expression of Ly-1 on splenic T cells and thymocytes. Thus, our findings demonstrate that conventional splenic B cells could express the Ly-1 transgene on their surface in vivo after LPS stimulation. Also discussed is the ES-derived chimeric hematopoietic system.

Animals↗
PubMed1990

Potent mitogenic effects of parathyroid hormone (PTH) on embryonic chick and rabbit chondrocytes. Differential effects of age on growth, proteoglycan, and cyclic AMP responses of chondrocytes to PTH.

The effect of PTH on chondrocyte proliferation as a function of cartilage age was examined. PTH[1-34] induced a 12- to 15-fold increase in the efficiency of colony formation in soft agar by chondrocytes from embryonic 13- to 19-d-old chickens and fetal 25-d-old rabbits with a 10-fold increase in their DNA content. It also caused a 2.5-fold increase in [3H]thymidine incorporation into DNA in fetal 25-d-old rabbit chondrocytes. No mitogenic responses to PTH were observed, however, in postnatal 7- to 21-d-old chick chondrocytes or postnatal 21-d-old rabbit chondrocytes. This age dependency was observed only with PTH: fibroblast growth factor, epidermal growth factor, and insulin stimulated chondrocyte proliferation irrespective of cartilage age. The absence of a mitogenic effect in postnatal chondrocytes was not due to a decrease in number or a reduction in affinity of receptors for PTH. PTH also increased [35S]sulfate incorporation into proteoglycans and the cyclic AMP level in fetal and postnatal chondrocytes, but at 100-fold higher concentrations (10(-8)-10(-7) M) than those (10(-10)-10(-9) M) required for the stimulation of cell division. These results suggest that PTH is a potent mitogen for embryonic chondrocytes, and that its mitogenic effect disappears selectively after birth.

Age Factors↗
PubMed1990

Long-term results in a case of meningioma treated by embolization alone--case report.

A 73-year-old female, unable to walk without a cane, was hospitalized for evaluation of left sensorimotor disturbance. Computed tomographic (CT) scans revealed a large parasagittal mass, which was markedly and homogeneously enhanced by contrast material. Bilateral external carotid angiograms showed that the middle meningeal arteries supplied the tumor. Both CT and angiographic findings suggested a right frontal parasagittal meningioma. Catheter embolization with Ivalon (polyvinyl alcohol foam) particles was carried out prior to the planned surgery for the purpose of decreasing intraoperative hemorrhage from the tumor. However, her clinical symptoms began to improve 9 days after the embolization procedure, and surgery was decided against because of her advanced age and symptomatic improvement. Ten months after embolization, she was able to walk unassisted and CT scans showed a 60% reduction of the pre-embolization tumor size. Four years after embolization, she remained nearly asymptomatic despite some regrowth of the tumor.

Aged↗
PubMed1990

Reconstruction for the vertebral artery stenosis at its origin--bypass surgery using a saphenous vein graft with external shunting.

Eight patients with vertebral artery (VA) stenosis at its origin were surgically treated by a new reconstructive technique. Two patients suffered vertebrobasilar transient ischemic attacks, and five had brainstem and/or cerebellar infarction. All patients had multiple stenotic lesions, including bilateral VA stenoses in one and unilateral VA stenosis plus contralateral VA occlusion in seven. They underwent a subclavian artery to VA bypass using a saphenous short vein graft with external shunting. Postoperatively, no patients had aggravated neurological symptoms, and angiography showed all bypasses to be patent. One had an episode of transient loss of consciousness 8 months postoperatively, but the others showed no episodes of ischemia during an average follow-up period of 2 years and 10 months. The results indicate that this procedure is safer and more useful than other surgical procedures.

Aged↗
PubMed1990

[Severe pancytopenic episodes in two cases with mosquito-allergy].

Two young females were admitted one by one because of peculiar skin eruptions suggesting mosquito-allergy and severe pancytopenia with normo-hypercellular bone marrow. The outcome of the first case was fatal on account of severe pancytopenia, immune deficiency and marked jaundice 14 months after the initial pancytopenic episode. In the post-mortem examination, HMR (histiocytic medullary reticulosis) was highly suggestive since hepatosplenomegaly with increase of Kupffer cells and large histiocytes including some atypical cells were detected. The second patient was treated with splenectomy because the past treatment were unsatisfactory in the first case and another cases in literatures. After the operation, the patient sustained almost normal blood cell level for 11 months without any treatment. As for the histopathological findings of resected spleen and lymphnodes, some erythrophagocytic mature histiocytes were found, but no atypical cells was detected. The relationship with pancytopenia, mosquito-allergy and HMR was discussed on the two cases and literatures.

Adolescent↗
PubMed1990

[A case report of superior vena cava reconstruction using a heparin-coated temporary bypass tube].

A 56-year-old woman with stage IIIB (c-T1N3M0) small cell lung cancer was treated with combination chemotherapy (CAVE). After five cycles of chemotherapy a surgical resection was performed. As mediastinal lymph nodes (#2, 3, 3a) had invaded to the superior vena cava, a heparin-coated tube was inserted into the left innominate vein and the right auricular appendage as a temporary bypass. Advantages of a heparin-coated tube for the temporary SVC bypass are as follows. 1) simple operative procedure. 2) enough flexibility to be kept out of the operative field. 3) no need for anticoagulants, consequently less bleeding resulted.

Blood Vessel Prosthesis↗
PubMed1990

Somatostatin receptors on human lymphocytes and leukaemia cells.

Receptors for somatostatin were identified on mitogen-activated human peripheral blood lymphocytes (PBL) and human leukaemic cells in 87.5% of lymphoblastic leukaemia and in 12.5% of non-lymphocytic leukaemia, using a somatostatin radiobinding assay. The specific binding of 125I-somatostatin of these cells increased linearly with the cell numbers and was suppressed by non-iodinated somatostatin. We investigated the distribution of fluorescent somatostatin to mitogen-activated PBL by using a fluorescence-activated cell sorter (FACS). Over 95% of the cell populations bound fluorescent somatostatin and no distinct predilection was found among certain lymphocyte subpopulations and somatostatin receptor-positive cells. Scatchard analysis showed a single class (low affinity) of binding site on mitogen-activated PBL and two classes (high and low affinity) of specific binding sites on lymphoblastic leukaemia cells.

Cell Separation↗