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Biomedical subjects

K Hatake

Publications and source records attributed to K Hatake.

At least 19 recordsLinked to original sources

Inhibitory effects of cadmium ion on extracellular Ca(2+)-independent contraction of rat aorta.

In vitro effects of cadmium ion on vasoconstriction, particularly on vasoconstriction independent of extracellular Ca2+, were investigated using isolated rat aorta. Aorta incubation with CdCl2 (0.01, 0.1 mM) significantly attenuated contractile responses to KCl and phenylephrine in the medium containing normal Ca2+ (2.5 mM). The contractile response to phenylephrine in the presence of calcium channel antagonists, nifedipine (1 microM) or verapamil (1 microM), was markedly inhibited by CdCl2 (0.1 mM). In the medium without Ca2+, phenylephrine (10 microM) induced a phasic contraction, which was markedly inhibited by CdCl2 (0.1 mM). In the medium without Ca2+, phorbol 12-myristate 13-acetate (1 microM) and okadaic acid (10 microM) caused tonic contractile responses, which were strongly attenuated by CdCl2 (0.1 mM) pretreatment. Contractile response to sodium fluoride (5 approximately 15 mM) in the absence of extracellular Ca2+ was strongly attenuated by CdCl2 (0.1 mM) pretreatment. These results suggest that cadmium ion depresses an extracellular Ca(2+)-independent component of agonist-induced vasoconstriction by hindering an intracellular contractile mechanism(s).

Animals

Endothelium-dependent relaxation resistant to NG-nitro-L-arginine in rat aorta.

Experiments were designed to determine whether cyclic GMP-independent relaxation is involved in the endothelium-dependent vascular relaxation response of rat aortic strip to acetylcholine. The relaxation response to acetylcholine in the presence of 3 x 10(-4) M NG-nitro-L-arginine was apparent when the precontraction was induced by norepinephrine at 5 x 10(-9) M or 10(-8) M. The relaxation response to acetylcholine resistant to NG-nitro-L-arginine was abolished by 10(-6) M atropine, 10 mM tetraethylammonium, or endothelium removal, but was not inhibited by 10(-5) M indomethacin, 3 x 10(-6) M oxyhemoglobin or 10(-5) M glibenclamide. The response was virtually abolished when the vascular strips had been preconstricted with 20 mM KCl. The increase in vascular cyclic GMP levels induced by 10(-5) M acetylcholine was completely abolished by 3 x 10(-4) M NG-nitro-L-arginine. These results suggest that acetylcholine-induced endothelium-dependent relaxation resistant to NG-nitro-L-arginine in rat aorta is unmasked when the precontractile force is caused by lower concentrations of norepinephrine and the relaxation is mediated by a cyclic GMP-independent mechanism, possibly an endothelium-derived hyperpolarizing factor.

Acetylcholine

Augmentation of cancer chemotherapy by preinjection of human macrophage colony-stimulating factor in L1210 leukemic cell-inoculated mice.

Human macrophage colony-stimulating factor (hM-CSF) is a potent stimulator of the effector functions of monocytes/macrophages. We investigated the antitumor effects of this factor in CDF1 male mice inoculated with L1210 cells, a mouse B-cell leukemia line. Mice preinoculated with various numbers of L1210 cells on day 0 were given intravenous injections of vehicle (human serum albumin; HSA) (100 micrograms/kg/day) or hM-CSF (20 micrograms/kg/day) for 3 days from day 1. In mice preinoculated with 10(2) L1210 cells but not with 10(3) or more L1210 cells, a marked increment in survival rate was observed with hM-CSF treatment. We next examined the effect of hM-CSF treatment combined with chemotherapy on the survival of mice that had been preinoculated with 10(5) L1210 cells. In our system, the administration of 4.9 mg/kg adriamycin (ADM) alone slightly prolonged survival of the tumor-bearing mice, but all of the mice died within 20 days. When hM-CSF was injected for 3 days before this ADM treatment, the invasion and proliferation of tumor cells in the liver and spleen were markedly inhibited and 50% of the mice were still alive at day 50. We detected inhibitory activity toward L1210 growth in serum of mice administered with hM-CSF, and the degree of the inhibitory activity was correlated with the level of nitrite (NO2-) in the serum. When L1210 cells were co-cultured with peritoneal macrophages from mice intraperitoneally injected with hM-CSF, the uptake of [3H]thymidine in L1210 cells was inhibited. The inhibition was abolished by the addition of NG-monomethyl-L-arginine, an inhibitor of NO2- synthesis, suggesting that the reactive nitrogen oxide intermediate is involved in hM-CSF-induced inhibition of L1210 growth.

Amino Acid Oxidoreductases

Transformation into acute basophilic leukaemia in a patient with myelodysplastic syndrome.

We describe a patient with basophilic leukaemia following a 2-year period with myelodysplastic syndrome (refractory anaemia). The marrow showed 59.4% of blasts with 25.0% of mature and immature basophils. The leukaemic blasts contained granules, positively stained with toluidine blue but negative for peroxidase. The basophilic differentiation was confirmed by ultrastructural analysis demonstrating immature basophil granules. In addition, a morphological transition from immature blasts to more mature basophils was observed. Immunophenotypic analysis of blasts and basophils showed positive for CD5, CD7, CD13, CD33 and CD34. Cytogenetic investigation showed an abnormal karyotype, 46,XY,del(5)(q31q35), in 11% of the cells examined when the initial diagnosis of refractory anaemia was made. However, expansion of the same clone up to 100% was observed concomitantly with transformation to basophilic leukaemia.

Anemia, Refractory

Methicillin-resistant Staphylococcus aureus: colonization and development of infection in patients with haematological disorders.

A retrospective study of 53 patients with haematological disorders whose bacterial cultures were positive for methicillin-resistant Staphylococcus aureus (MRSA), was performed to analyse the risk factors for MRSA infection, and the prognostic factors. Sixteen patients showed colonization by MRSA but never developed infection(C), 16 showed colonization and subsequent infection(C-I), while 21 had MRSA infection at the time of first culture (I). Poor performance status, thrombocytopenia, increased serum urea nitrogen and decreased serum cholinesterase were more prominent in (I) than (C) + (C-I). The risk factors associated with the development of infection from colonization were age and serum cholinesterase. In addition, lower respiratory tract infection as a type of infection, non-remission status of the haematological malignancy and an inappropriate antibiotic therapy were associated with a poor prognosis for MRSA infection.

Blood Urea Nitrogen

Monocyte chemoattractant protein-1 stimulates tumor necrosis and recruitment of macrophages into tumors in tumor-bearing nude mice: increased granulocyte and macrophage progenitors in murine bone marrow.

Monocyte chemoattractant protein-1 (MCP-1) belongs to the newly recognized "chemokine" superfamily of activation-inducible cytokines. We report here that MCP-1 gene-transferred mouse myeloma cells modulate tumor necrosis in myeloma-bearing nude mice. We established an MCP-1-producing myeloma cell line (X63-MCP-1) by transfection with human MCP-1 cDNA as well as interleukin-8-producing X63 cells (X63 IL-8). Each cell line showed the same growth characteristics in vitro, and 1 x 10(7) cells per mouse were injected into the peritoneal cavity resulting in the formation of tumors. Hematologic studies, including peripheral white blood cell counts and differentiation, showed no differences among the groups. They formed tumors in the same manner, which we observed from weeks 2.5 to 9. MCP-1 mice showed more tumor necrosis and infiltration of the macrophages into the tissue surrounding the tumor. In situ hybridization, using a partial cDNA as a probe, showed that macrophages contained MCP-1 mRNA. Bone marrow cell colony-forming assay showed a greater number of both granulocyte and macrophage colonies in MCP-1 mouse femur than in those of controls or interleukin-8 mice. MCP-1 has no direct stimulatory activity on stem cells, but longer exposure to MCP-1 in vivo might stimulate both granulocyte and macrophage progenitors and recruitment of macrophages into tumors, and it might explain the antitumor activity of macrophages in tumor-bearing nude mice.

Animals

Quantitative analysis of the two macrophage colony-stimulating factor mRNA expressed in a human stromal cell line by reverse transcription-polymerase chain reaction (RT-PCR).

We established a quantitative analysis system for 4.0 kb and 1.6 kb macrophage colony-stimulating factor (M-CSF) mRNA, using reverse transcription-polymerase chain reaction. Using this system, we performed quantitative analysis of the two mRNAs expressed in the human stromal cell line, KM102, in the resting condition and when stimulated by various concentrations of interferon-gamma (IFN-gamma). The expression of 1.6 kb M-CSF mRNA was more efficiently stimulated by IFN-gamma than that of 4.0 kb M-CSF mRNA. The alternative splicing of a single M-CSF gene has been shown to generate several M-CSF proteins with different localization; we believe that molecular analysis of the transcription products by this system is important to better understand the physiological significance of the different species of M-CSF derived from each mRNA.

Base Sequence

Aclarubicin inhibits phosphatidylinositol hydrolysis and contraction of rat aorta.

The effects of aclarubicin on phosphatidylinositol hydrolysis and contractile responses were investigated in isolated rat aorta. In the aclarubicin-pretreated aorta, the basal level of [3H]inositol monophosphate accumulation was significantly lower whereas [3H]phosphoinositide formation was significantly higher than in the saline-pretreated control aorta. Phenylephrine-, 5-hydroxytryptamine- and sodium fluoride-stimulated increases in [3H]inositol monophosphate accumulation were also significantly reduced in the aclarubicin-treated aorta compared to the control. Contractile forces induced by 5-hydroxytryptamine and sodium fluoride were markedly diminished in the aclarubicin-treated aorta. These results suggest that aclarubicin inhibits phosphatidylinositol hydrolysis at a level of phospholipase C activation, which is involved in the reduction of agonist-induced contraction of rat aorta.

Aclarubicin

Induction of tumor necrosis factor in mice by recombinant human macrophage colony-stimulating factor.

The effect of recombinant human macrophage colony-stimulating factor (rhM-CSF) on endogenous production of tumor necrosis factor (TNF) was investigated in mice. The intravenous injection of lipopolysaccharide (LPS) after the administration of rhM-CSF via the same route induced the production of endogenous cytotoxic activity in serum as assessed by using TNF-sensitive murine L929 cells. The intravenous injection of LPS alone or rhM-CSF alone did not induce cytotoxic activity. The priming effect of rhM-CSF was transient and the optimal duration between injections of primer and trigger was 3 h, while the optimal duration between trigger injection and serum sampling was 1 h after LPS injection. Moreover, preinjection of rhM-CSF enhanced the priming effect of recombinant mouse interferon-gamma. No triggering effect of rhM-CSF was observed. The cytotoxic activity in the serum was completely neutralized by anti-mouse TNF-alpha polyclonal antibody. These results indicate that rhM-CSF can be used as a priming agent for endogenous production of TNF in vivo, and raise the possibility of using rhM-CSF in cancer immunotherapy.

Animals

Development of acute myeloblastic leukaemia in a case of aplastic anaemia treated with granulocyte colony-stimulating factor.

We report a case of aplastic anaemia (AA) treated with granulocyte colony-stimulating factor (G-CSF) terminating as acute myeloblastic leukaemia (AML). Because of severe pneumonia, 250 micrograms of G-CSF was administered for 30 d to promote neutrophil recovery. Following G-CSF therapy, myeoblasts appeared, and the diagnosis of AML was then made. The myeloblasts proliferated in response to G-CSF in vitro and in vivo. In AA, development of AML after treatment with G-CSF is rare. Therefore a careful observation for leukaemic transformation is necessary in long-term administration of G-CSF for AA.

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