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1.
An enzyme-linked immunosorbent assay (ELISA) system for the quantitation of human monocytic colony-stimulating factor (hM-CSF) was established, which was based on the "dual antibody immunometric sandwich" principle using horse and rabbit polyvalent antibodies against human urinary colony-stimulating factor (CSF-HU). The minimal detectable level of hM-CSF was 10 U/mL, and the assays showed good reproducibility. As measured by this method, the average serum hM-CSF level of 20 normal adults was 540 +/- 110 U/mL (range, 300 to 800 U/mL). The peak of hM-CSF measured by ELISA was identical to that measured by bioassay when semipurified CSF-HU was fractionated by reversed-phase high performance liquid chromatography (HPLC). This method detected two types of hM-CSF, which had approximate molecular weights of 85 Kd (CSF-HU) and 45 Kd in human serum and urine; the ratio of 85:45 Kd was very high in serum and the amounts of the two types were nearly equal in urine. After anticancer chemotherapy, the serum hM- CSF level of one half of the patients with hematological malignancy was elevated according to the reduction in neutrophil number, while it was almost in the normal range in the other half of the patients, indicating the possibility that anticancer chemotherapy damaged the hM- CSF-producing cells. This ELISA method may be useful for monitoring the serum hM-CSF level after anticancer chemotherapy.  相似文献   
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The SH2 domain-containing inositol 5'-phosphatase (SHIP) is crucial in hematopoietic development. To evaluate the possible tumor suppressor role of the SHIP gene in myeloid leukemogenesis, we examined primary leukemia cells from 30 acute myeloid leukemia (AML) patients, together with eight myeloid leukemia cell lines. A somatic mutation at codon 684, replacing Val with Glu, was detected in one patient, lying within the signature motif 2, which is the phosphatase active site. The results of an in vitro inositol 5'-phosphatase assay revealed that the mutation reduced catalytic activity of SHIP. Leukemia cells with the mutation showed enhanced Akt phosphorylation following IL-3 stimulation. K562 cells transfected with the mutated SHIP-V684E cDNA showed a growth advantage even at lower serum concentrations and resistance to apoptosis induced by serum deprivation and exposure to etoposide. These results suggest a possible role of the mutated SHIP gene in the development of acute leukemia and chemotherapy resistance through the deregulation of the phosphatidylinositol-3,4,5-triphosphate (PI(3,4,5)P3)/Akt signaling pathway. This is the first report of a mutation in the SHIP gene in any given human cancer, and indicates the need for more attention to be paid to this gene with respect to cancer pathogenesis.  相似文献   
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Conservation Genetics Resources - We have developed microsatellite DNA markers for Mesopodopsis orientalis (Tattersall 1908), a widely distributed mysid crustacean in shallow waters of the coastal...  相似文献   
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Fetuin is a biocompatible plasma protein and strongly enhances phagocytosis of bacteria, DNA and apoptotic cells by peripheral blood cells such as monocytes, macrophages and dendritic cells. We developed a novel gene delivery system: ternary complexes constructed with pDNA, polyethylenimine (PEI) and fetuin. Without covalent binding, fetuin was able to coat pDNA–PEI complexes, and stable anionic nanoparticles formed at a weight ratio greater than 30. Optimised pDNA–PEI–fetuin complexes significantly decreased the cytotoxicity of pDNA–PEI complexes in the melanoma cell line B16F10. Furthermore, the pDNA–PEI–fetuin complexes had higher transgene efficiency compared to that of commercial lipofectin previously reported in B16F10 cells despite an anionic surface. The pDNA–PEI–fetuin complexes did not agglutinate with erythrocytes. The pDNA–PEI–fetuin complexes had high gene expression in the spleen after intravenous administration in mice. Thus, the pDNA–PEI–fetuin complexes were a useful in vivo gene delivery system with tropism for the spleen.  相似文献   
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Multiple myeloma(MM) is a neoplasia of plasma cells in bone marrow. High dose chemotherapy followed by stem cell transplantation and new drugs such as thalidomide and bortezomib have improved the survival in MM. However, most of patients with myeloma are incurable so there is a need for the new therapeutic approaches that have been developed against molecular targets and pathway. It has been reported that activation of NF-kappaB pathway was required to survival of myeloma cells and this pathway was the potential target for anti -MM therapy. Recently we reported diverse genetic aberrations that activated NF-kappaB signaling in MM. In this section, the molecular pathogenesis of myeloma, especially the new findings related with NF-kappaB activation, will be reviewed in Japanese.  相似文献   
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We examined the effects of gamma-aminobutyric acid (GABA) on the blood pressure in spontaneously hypertensive rats and normotensive Wistar-Kyoto rats. A single oral administration (0.5 mg/kg) significantly lowered the systolic blood pressure in spontaneously hypertensive rats, but not in normotensive rats. In the mesenteric arterial bed, the perivascular nerve stimulation-induced increase in perfusion pressure and noradrenaline release were significantly inhibited by GABA in spontaneously hypertensive rats, but not in normotensive rats, and attenuated by the selective GABA(B) receptor agonist, baclofen, but not by the selective GABA(A) receptor agonist muscimol. The inhibitory effects of GABA on the perivascular nerve stimulation-induced increase in perfusion pressure and noradrenaline release were completely antagonized by the selective GABA(B) receptor antagonist, saclofen, but not by the selective GABA(A) receptor antagonist, bicuculline. These results suggest that, in spontaneously hypertensive rats, GABA has an antihypertensive effect due to its inhibition of noradrenaline release from sympathetic nerves in the mesenteric arterial bed via presynaptic GABA(B) receptors.  相似文献   
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During development thalamocortical (TC) axons establish lamina-specific connections with cortical cells, and in later developmental stages TC projections are modified by activity-dependent processes. Recent studies have demonstrated that brain-derived neurotrophic factor and neurotrophin-3 are expressed in the cortex with distinct developmental time courses, and are involved not only in the formation of the TC projection but also in the subsequent refinement processes. Evidence further suggests that these actions of neurotrophins are achieved in cooperation with membrane-associated molecules expressed in cortical cells.  相似文献   
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