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Biomedical subjects

S Asano

Publications and source records attributed to S Asano.

At least 19 recordsLinked to original sources

Antidepressant-like effect by postsynaptic 5-HT1A receptor activation in mice.

The antidepressant-like effect of 5-(3(-)[((2S)-1,4-benzodioxan-2-ylmethyl)amino]propoxy)-1,3- benzodioxole (MKC-242), a novel 5-HT1A receptor agonist, was studied in the forced swimming test in mice injected i.c.v. with 5,7-dihydroxytryptamine to destroy 5-HT neurons or treated with p-chlorophenylalanine to inhibit 5-HT synthesis. MKC-242 reduced immobility time of mice pretreated with vehicle and these drugs, although it did not affect their locomotor activity. The anti-immobility effect was antagonized by 5-HT1A receptor antagonists such as propranolol and N-tert-butyl-3-(4-(2-methoxyphenyl)piperazin-1-yl)-2-phenylpropana mide. These findings support the hypothesis that postsynaptic 5-HT1A receptors play an important role in the antidepressant-like effect of 5-HT1A receptor agonists.

5,7-Dihydroxytryptamine

A synergistic increase in transplantable peripheral blood stem cells in mice by co-administration of recombinant human interleukin 6 and recombinant human granulocyte colony-stimulating factor.

We examined the effects of co-administration of recombinant human (rh) IL-6 (10 micrograms/day) and rh granulocyte colony-stimulating factor (G-CSF) (0.35 micrograms/day) on the number of peripheral blood cells and peripheral progenitor cells in mice. Among blood cells counts, only white blood cells were synergistically enhanced by co-administration of rhIL-6 and rhG-CSF. Moreover, it was found that co-administration of rhIL-6 and rhG-CSF also caused a marked synergistic increase in the number of peripheral blood progenitor cells. Namely, in combination with rhG-CSF, which alone induced a 170-fold increase in peripheral granulocyte-macrophage colony-forming units (CFU-GM) on day 14, rhIL-6 synergistically increased the number of CFU-GM to more than 1600-fold higher than the number in control mice. Administration of rhIL-6 alone induced a 46-fold increase in CFU-GM. Similar synergistic increases of other hematopoietic progenitors, such as colony-forming units in spleen and megakaryocyte colony-forming units in blood, were also observed in mice co-administered rhIL-6 and rhG-CSF. The survival rate of lethally irradiated recipient mice transplanted with mononuclear cells from 100 microliters of blood from mice administered rhIL-6 and/or rhG-CSF was examined. When mononuclear cells from mice co-administered rhIL-6 and rhG-CSF were injected, survival rate at day 100 was 92%. In contrast, recipient mice transplanted with mononuclear cells from mice administered either rhIL-6 or rhG-CSF alone showed a survival rate of 31% or 46%, respectively, although transplantation of mononuclear cells from control mice failed to rescue any lethally irradiated recipient mice. These results suggest that co-administration of rhIL-6 and rhG-CSF may be useful for peripheral blood stem cell transplantation.

Animals

Analysis of the genetic information of a DNA segment of a new virus from silkworm.

In 1983, a parvo-like virus (Yamanashi isolate) was newly isolated from silkworm. However, unlike parvovirus, two DNA molecules (VD1 and 2) were always extracted from purified virions. To investigate the structure and organization of the virus genomes, we determined the complete nucleotide sequence of VD2. The sequence consisted of 6031 nucleotides (nts) and contained a large open reading frame (ORF1) with 3513 nts. A smaller open reading frame (ORF2) with 702 nts was found in the complementary sequence. Computer analysis revealed that both ORFs did not code for the major structural proteins (VP1, 2, 3, and 4). These results suggest that VD2 has not enough information to produce progeny virions by itself. Further, the structural importance of the terminal sequence (CTS) common to both VD1 and VD2 was also predicted by a computer analysis.

Amino Acid Sequence

Highly efficient adenovirus-mediated gene transfer into renal cells in culture.

In summary, we have shown that adenovirus vector efficiently introduced foreign gene into cultured renal cells both of mesangial and tubular origin. Genes transferred were properly expressed to produce the molecules of expected function. It was possible to introduce the gene into nearly 100% of the cells treated. Expression of the gene began as early as 12 hours after the infection, increased until 48 hours and persisted at least up to eight days. Finally, the vector was non-toxic to the cells, as judged from simple toxicity tests. Successful application of adenovirus vector enables for us to study function of pertinent molecules in suitable host cells and opens a new way for examining renal cellular physiology and pathophysiology.

Adenoviruses, Human

Intracellular ascorbic acid inhibits the Na(+)-Ca2+ exchanger in cultured rat astrocytes.

The effect of ascorbic acid on Ca2+ uptake in cultured rat astrocytes was examined in the presence of ouabain and monensin, which are considered to drive the Na(+)-Ca2+ exchanger in the reverse mode. Ascorbic acid at 0.1-1 mM inhibited Na(+)-dependent Ca2+ uptake significantly but not Na(+)-dependent glutamate uptake in the cells, although the inhibition required pretreatment for more than 30 min. The effect of ascorbic acid on the Ca2+ uptake was blocked by simultaneous addition of ascorbate oxidase (10 U/ml). Na(+)-dependent Ca2+ uptake was also inhibited by isoascorbate at 1 mM but not by ascorbate 2-sulfate, dehydroascorbate, and sulfhydryl-reducing reagents such as glutathione and 2-mercaptoethanol. The inhibitory effect of ascorbic acid was observed even in the presence of an inhibitor of lipid peroxidation, o-phenanthroline, or a radical scavenger, mannitol, and the degrading enzymes such as catalase and superoxide dismutase. On the other hand, the inhibitory effect was not observed under the Na(+)-free conditions that inhibited the uptake of ascorbic acid in astrocytes. When astrocytes were cultured for 2 weeks in a medium containing ascorbic acid, the content of ascorbic acid in the cells was increased and conversely Na(+)-dependent Ca2+ uptake was decreased. These results suggest that an increase in intracellular ascorbic acid results in a decrease of Na(+)-Ca2+ exchange activity in cultured astrocytes and the mechanism is not related to lipid peroxidation.

Animals

Nitroprusside and cyclic GMP stimulate Na(+)-Ca2+ exchange activity in neuronal preparations and cultured rat astrocytes.

The effects of nitric oxide (NO)-generating agents on 45Ca2+ uptake in rat brain slices and cultured rat astrocytes were studied in the presence of monensin, which is considered to drive the Na(+)-Ca2+ exchanger in the reverse mode. Sodium nitroprusside (SNP) at > 10 microM increased monensin-stimulated Ca2+ uptake in the slices, although it did not affect high K(-)-stimulated Ca2+ uptake. Another NO donor, 3-morpholinosydnonimine, was effective. The effect of SNP was antagonized by hemoglobin (50 microM), a NO scavenger, and mimicked by 8-bromo-cyclic GMP (100 microM). In rat brain synaptosomes, SNP increased monensin-stimulated Ca2+ uptake, but it did not affect high K(+)-stimulated Ca2+ uptake. 8-Bromocyclic GMP, but not SNP, increased Na(+)-dependent Ca2+ uptake significantly in synaptic membrane vesicles in the absence of monensin. In cultured rat astrocytes, SNP and 8-bromo-cyclic GMP increased Ca2+ uptake in the presence of ouabain and monensin, which were required for the Ca2+ uptake in the cells. These findings suggest that NO stimulates the Na(+)-Ca2+ exchanger in neuronal preparations and astrocytes in a cyclic GMP-dependent mechanism.

Animals

Increase of noradrenaline release in the hypothalamus of freely moving rat by postsynaptic 5-hydroxytryptamine1A receptor activation.

1. 5-Hydroxytryptamine (5-HT) plays a role in the regulation of noradrenergic neurones in the brain, but the precise mechanism of regulation of noradrenaline (NA) release by 5-HT1A receptors has not been defined. The present study describes the effect of a highly potent and selective 5-HT1A receptor agonist, 5-(3-[[(2S)-1,4-benzodioxan-2-ylmethyl)]amino]propoxy)-1,3-b enzodioxole HC1 (MKC-242), on NA release in the hypothalamus using microdialysis in the freely moving rat. 2. Subcutaneous injection of MKC-242 (0.5 mg kg-1) increased extracellular levels of NA and its metabolite, 3-methoxy-4-hydroxyphenylglycol, in the hypothalamus and hippocampus. 3. The 5-HT1A receptor agonists, 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT) (0.2 mg kg-1) and buspirone (3 mg kg-1) mimicked the effect of MKC-242 in increasing NA release in the hypothalamus. 4. The effects of MKC-242 and 8-OH-DPAT in the hypothalamus were antagonized by pretreatment with WAY100135 (10 mg kg-1), a silent 5-HT1A receptor antagonist. 5. Local administration of 8-OH-DPAT (10-100 microM), citalopram (1 microM), a 5-HT reuptake inhibitor, and MDL72222 (10 microM), a 5-HT3 receptor antagonist, into the hypothalamus, had no effect on NA release. 6. Intracerebroventricular injection with 5,7-dihydroxytryptamine caused a marked reduction in brain 5-HT content, but the treatment affected neither basal NA levels nor the MKC-242-induced increase in NA release. 7. The effect of MKC-242 in increasing NA release was not attenuated by repeated treatment with the drug (0.5 mg kg-1, once a day for 2 weeks). 8. The present results suggest that activation of postsynaptic 5-HT1A receptors increases NA release in the hypothalamus.

5,7-Dihydroxytryptamine

[Therapeutic evaluation of combination therapy using human native immunoglobulin preparation for i.v. administration, with antibiotics and G-CSF in severe infections in the field of internal medicine].

A human native immunoglobulin liquid preparation for intravenous injection, was used in combination with antibiotics and G-CSF to study its efficacy and safety in 49 patients with severe infections (Granulocyte counts were or= 38 degrees C) which had not responded to antibiotic and G-CSF therapy of a 3-day or more duration. As a result of the Committee judgment, 49 patients were included in this study; 30 (61.7%) were included in efficacy and safety analysis. The analysis of 30 patients consisted of 9 patients (30.0%) with suspected septicemia, 5 (16.7%) with pneumonia, and 4 (13.3%) with septicemia. All patients had severe underlying diseases such as leukemia and malignant lymphoma. Clinical efficacy of Immunoglobulin preparation was judged by the doctors in charge to be "excellent" and "good" in 70.0% of the total cases. The rate of effectiveness was calculated from the results of the Committee judgment was 83.3% when "excellent" and "good" cases were included. No side effects were observed in all cases. Our results suggest that the immunoglobulin in combination with G-CSF is very effective on patients with severe infections.

Adult

[Efficacy of combination chemotherapy with miconazole and G-CSF in deep mycosis accompanying hematological diseases].

In order to examine the efficacy of the combination chemotherapy with miconazole and G-CSF, patients with deep mycosis and suspected deep mycosis were divided into 3 groups. Group I: miconazole and G-CSF were administered simultaneously. Group II: miconazole was administered later during G-CSF administration. Group III: only miconazole was administered. Of a total of 117 cases 105 cases were analyzed including group I 37 cases, group II 39 cases and group III 29 cases, excluding 12 dropout and inadequate cases. Of the 105 cases, deep mycosis were 31 and suspected deep mycosis were 74, and underlying diseases were hematological malignancies such as leukemias. Efficacy judged mainly by the change of fever was 62.2% (23/37) in group I, 43.6% (17/39) in group II, and 41.4% (12/29) in group III, respectively. Efficacy was better in the patients whose neutrophil counts increased from less than 500/microliters to more than 500/microliters (group I 75.0%, group II 72.7%) than in the patients whose neutrophil counts were less than 500/microliters throughout the time of miconazole administration (group I 33.3%, group II 33.3%). Adverse effects were minimal in 3 groups (group I 15.4%, group II 17.4%, group III 15.6%). It is concluded that the combination with miconazole and G-CSF is effective in the treatment of deep fungal infections.

Adult

A morphologic study of lung secretory leukoprotease inhibitor in pneumonia.

The present study was undertaken to determine the localization of cells laden with secretory leukoprotease inhibitor (SLPI) in bronchial/bronchiolar epithelium (B/Br-E) by histochemical techniques to see whether SLPI production occurs in conjunction with pathologic bronchopneumonia. Ten lung were obtained at autopsy from patients between 63 and 100 yr of age, including six with pathologic pneumonia and four without pneumonia. SLPI-laden cells in the B/Br-E corresponded mostly to goblet cells with apparent hyperplasia. A morphometric study performed on the B/Br-E indicated that the percentage of SLPI-laden cells was significantly correlated with the percentage of mucus-containing cells (r = 0.72, p < 0.001). This trend was similar in the bronchi (r = 0.60, p < 0.05) and in the bronchioles (r = 0.90, p < 0.01). The increased percentage of mucus and SLPI-laden cells in the B/Br-E was closely correlated with acute inflammatory changes in the adjacent alveoli, particularly in bronchi rather than in bronchioles. From these observations we conclude that the number of SLPI-laden cells in the airways increases in correlation with goblet cell hyperplasia. In addition, these morphologic changes are associated with the existence of acute inflammatory cell infiltration in the alveolar area.

Aged

Effects of serotonin1A agonists on anoxia-induced impairment of protein synthesis in rat brain slices.

Earlier in vivo experiments suggest that serotonin1A (5-HT1A) agonists are new tools for the treatment of experimental cerebral ischemia. The present study examined this idea in an in vitro system. Incubation of rat brain slices under anoxic conditions for 30 min decreased protein synthesis that was assayed in a normoxic medium by measuring the incorporation of [14C]lysine into trichloroacetic acid-insoluble tissue extracts. The 5-HT1A agonists 8-hydroxy-2-(di-n-propylamino) tetralin (10-100 microM) and buspirone (50 microM) attenuated the anoxia-induced decrease in protein synthesis in the slices. Although the degree of the effect is small, it may be relevant to the neuroprotective effect in the in vivo experiments.

8-Hydroxy-2-(di-n-propylamino)tetralin

Clinical significance of serial measurement of the serum levels of soluble interleukin-2 receptor and soluble CD8 in malignant lymphoma.

We serially measured the serum levels of soluble interleukin-2 receptor (sIL-2R) and soluble CD8 (sCD8) in 36 patients with malignant lymphoma (33 non-Hodgkin's lymphoma cases and three Hodgkin's disease cases). The level of serum sIL-2R was significantly elevated in patients with active disease (18) compared to those in remission (18), and correlated with the clinical stage of the lymphoma. The temporal profile of the sIL-2R level reliably represented the disease status, which was judged clinically, during the course of the disease. In three patients, the tumor bulk paralleled the sIL-2R level. On the other hand, a less significant correlation was found between the serum sCD8 level and disease activity. The serial measurement of sCD8 appeared to be less useful for monitoring the disease activity, although there was a significant correlation between the sCD8 and sIL-2R levels. This study indicates that serial measurement of the serum sIL-2R level may be useful for monitoring the tumor burden in response to treatment and for early detection of disease progression in malignant lymphoma.

Adult

HRX gene rearrangement in secondary acute lymphoblastic leukemia.

The human tri-thorax gene (HRX) also called ALL-1 (Acute Lymphocytic Leukemia-1) as well as MLL (Myeloid-lymphoid or Mixed-lineage Leukemia) gene, is disrupted in the majority of leukemias with chromosomal abnormalities involving 11q23. The alteration of the gene is related to leukemogenesis of various types such as acute myelogenous leukemia (AML), acute lymphoblastic leukemia (ALL), and acute mixed lineage leukemia. The gene is also rearranged in cases of secondary AML developing after exposure to chemotherapeutic agents, especially topoisomerase II inhibitors. In at least one report, genomic analysis of this recombination site showed the breakpoint to be a topoisomerase II binding site and that exposure to the inhibitor could induce the rearrangement. If exposure induces the rearrangement of the gene, secondary ALL as well as secondary AML could occur after exposure to these agents, because the type of leukemias with rearranged HRX gene is not limited to AML. We present here such a case of secondary ALL with this gene rearrangement which occurred during adjuvant chemotherapy for breast cancer. Although less cases of secondary ALL are reported in comparison with those of secondary AML, such case reports have been accumulating. The incidence of this type of leukemia should be clarified in the future.

Antineoplastic Agents

[The effects of recombinant human granulocyte colony-stimulating factor on protracted neutropenia in patients with acute myelogenous leukemia. (rG.CSF Clinical Study Group)].

A clinical study to investigate the efficacy and safety of recombinant human G-CSF (rG.CSF) was performed in patients with acute myelogenous leukemia who had had protracted neutropenia. The drug was administered d.i.v. at a dose of 5 micrograms/kg. Sixty-four patients entered the study, of whom 61 patients were evaluable for safety and 58 patients evaluable for efficacy. The treatment produced an early recovery in neutrophil count in the patients who had had protracted neutropenia (< 1,000/microliters) of over 10 days. Among relapsed cases and cases showing > 20% blasts in the bone marrow, many showed blast stimulation in response to rG.CSF, suggesting difficulty in attaining complete remission by subsequent chemotherapy in such cases. The present data indicates that it is desirable to use the drug in lower-blast-count states in order to attain safe and sufficient therapeutic effects in patients with acute myelogenous leukemia who have had protracted neutropenia.

Adolescent

[A randomized controlled study of rG.CSF in patients with neutropenia after induction therapy for acute myelogenous leukemia. (rG.CSF Clinical Study Group)].

A randomized treated/non-treated study of rG.CSF (5 micrograms/kg/d, d.i.v.) in patients with acute myelogenous leukemia was conducted to assess its efficacy on fever (> or = 38 degrees C) or documented infection after induction therapy. Of 95 patients enrolled, 46 patients were evaluable for safety and 43 for efficacy in the treated group of 47 patients while 37 of 48 patients were eligible for data analysis in the untreated group. Mare patients showed a recovery in the blood neutrophil count (to > 1,000/microliters) during rG.CSF treatment (14 days) than in the non-treated group (p = 0.039) while the number of febrile patients and duration of fever did not significantly differ between the two groups. The treatment with rG.CSF enabled an early recovery in neutrophil count in the patients with neutropenia and overt signs of infection after induction therapy, but there was no hastened allevistion of symptoms of infection in these patients.

Adolescent

[A randomized double-blind controlled study of recombinant human granulocyte colony-stimulating factor in patients with neutropenia induced by consolidation chemotherapy for acute myeloid leukemia. (rG.CSF clinical study group)].

A multicenter, randomized, double-blind controlled study was performed to evaluate the efficacy and safety of recombinant human granulocyte colony-stimulating factor (rG.CSF) in reducing infectious morbidity and neutropenia induced by consolidation chemotherapy for acute myeloid leukemia (AML). One hundred and twenty-four eligible patients were randomized to receive either rG.CSF (5 micrograms/kg/d d.i.v.; 59 patients) or placebo (65 patients) for 14 days from the day after chemotherapy. All of them were included in the safety analysis, while 57 patients receiving rG.CSF and 64 patients receiving placebo were included in the efficacy analysis. The duration of neutropenia as well as the incidence of fever and febrile neutropenia, and frequency of antibiotic therapy required, were all significantly reduced in the rG.CSF group. No serious adverse reactions were encountered; there was no significant difference between the two groups in terms of incidence of adverse events. These results demonstrate that rG.CSF is beneficial to alleviate neutropenic episodes induced by consolidation chemotherapy in patients with AML.

Adolescent