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Biomedical subjects

S Asano

Publications and source records attributed to S Asano.

At least 307 records · Page 17Linked to original sources
PubMed1994

A time course study for optimal harvest of peripheral blood progenitor cells by granulocyte colony-stimulating factor in healthy volunteers.

In a search for the optimal method to harvest peripheral blood progenitor cells (PBPC) without myeloablative chemotherapy, we administered recombinant human granulocyte colony-stimulating factor (G-CSF) to adult, healthy volunteers and investigated the mobilization rate of the PBPC. The consecutive subcutaneous administration of G-CSF in a dose of 2 micrograms/kg/d for 5 days significantly increased colony-forming units-granulocyte/macrophage (CFU-GM) up to 2340 +/- 980 per mL whole blood with a 30 +/- 21-fold mobilization of PBPC, range 11- to 76-fold. Burst-forming units-erythroid (BFU-E) and mixed erythroid progenitors (CFU-Mix) were also increased, and the mobilization rate was 8.4 +/- 4.5-fold and 7.6 +/- 4.7-fold, respectively. A time course study of PBPC after final G-CSF injection was done for 0 to 30 hours on days 1, 3, and 5. After a single administration of G-CSF (day 1), there was no increment of PBPC during the subsequent 30 hours, but the white blood cell count (WBC) markedly increased. Three days after the injection of G-CSF, no increase of CFU-GM was seen during the first 2 hours, then a significant, time-dependent increase occurred for up to 30 hours. Five days after the injection of G-CSF, there was no increase of CFU-GM during the first 2 hours, and the significant increase at 24 hours was maintained for up to 30 hours. BFU-E and CFU-Mix showed the same pattern of expansion as seen with CFU-GM. Thus, subcutaneous administration of 2 micrograms/kg/d G-CSF for 5 days will lead to a successful PBPC harvest for transplantation, and the most suitable period for this is 24 to 30 hours after the final G-CSF administration.

Adult↗
PubMed1994

The apical chloride channel as part of the function of gastric H+,K(+)-ATPase.

Gastric intracellular tubulovesicles fuse with the apical membrane upon histamine stimulation. Disulfide cross-linking of isolated gastric tubulovesicles by cupper-o-phenanthroline (CuP) opened the chloride channel in the vesicles. A functional monoclonal antibody raised against H+,K(+)-ATPase of gastric vesicles inhibited both the enzyme activity and the CuP-induced opening of the chloride channel. This fact indicates that the chloride channel is part of the function of the ATPase. Another evidence which supports the above concept that both the pump and the chloride channel coexist in the same molecule was obtained in this study. The conformation of H+,K(+)-ATPase was changed in the direction of E2 form by incubation with SCH 28080 or low concentrations of K+. SCH 28080 is an H+,K(+)-ATPase specific inhibitor and binds to the high affinity K+ site. Both SCH 28080 and K+ inhibited the channel opening, indicating that the channel opening by the S-S cross-linking depends on the conformational state of the enzyme.

Animals↗
PubMed1994

Allogeneic bone marrow transplantation in Japan.

Allogeneic bone marrow transplantation (BMT) is being used increasingly to treat diverse diseases in Japan. The distinctive aspects of allogeneic BMT in Japan include the lower incidence of acute graft-versus-host disease, which may be attributable to less disparity in histocompatibility antigens in Japanese. Research in the field of allogeneic BMT in Japan has covered the use of recombinant hemopoietic growth factors, especially granulocyte colony-stimulating factor, and novel immunosuppressive agents.

Bone Marrow Transplantation↗
PubMed1994

A marked decrease in defensin mRNA in the only case of congenital neutrophil-specific granule deficiency reported in Japan.

A deficiency of defensins (human neutrophil peptides, HNP) has been previously demonstrated in two individuals with congenital neutrophil-specific granule deficiency (SGD), but its genetic basis is not well understood. We have studied another case of SGD, the only case reported in Japan, to elucidate the molecular basis of defensin deficiency. Using Western blot analysis, we showed for the first time that HNP-4, a novel human defensin, was also deficient in the patient's neutrophils. Northern blot analysis demonstrated that the defensin mRNA was absent in the bone marrow cells of the patient. Limited Southern blot analysis, using a defensin cDNA probe, did not reveal any differences in fragment patterns of the genomic DNA between the patient and the control. We propose that the defensin deficiency in our patient is a consequence of a marked decrease in defensin mRNA in neutrophil precursors. Our findings were consistent with a previous speculation suggesting that the SGD defect occurs at the level of transcription.

Adult↗
PubMed1994

Recombinant human non-glycosylated granulocyte-macrophage colony-stimulating factor in allogeneic bone marrow transplantation: double-blind placebo-controlled phase III clinical trial.

In a randomized double-blind placebo-controlled phase III clinical trial, the effects of a non-glycosylated recombinant human granulocyte-macrophage colony-stimulating factor (CSF 39-300) were investigated in patients who had received allogeneic bone marrow transplantation. CSF 39-300 was administered at a daily dose of 10 micrograms/kg (maximum dose, 300 micrograms/body) via three-hour intravenous infusions from days 1 to 21 following reinfusion of the marrow. Twenty-eight patients received CSF 39-300 and 25, placebo. The median number of days to recovery for leucocytes (> or = 1000/mm3), neutrophils (> or = 500/mm3), lymphocytes (> or = 300/mm3) and reticulocytes (> or = 20/1000) were significantly shortened (16 vs 20, 17 vs 21 and 22 vs 28, respectively) with CSF 39-300. The duration of stay in laminar-air-flow room after transplantation was also significantly shortened in the CSF 39-300 group (21 vs 30 days). There was no significant difference in the incidence of acute or chronic graft-versus-host disease between the two groups. A follow-up during the year after transplantation revealed there to be no significant difference in either survival rate or leukemia relapse rate between the two groups. CSF 39-300 is therefore considered useful after allogeneic bone marrow transplantation, especially in the early period.

Adolescent↗
PubMed1993

An ets-related gene, ERG, is rearranged in human myeloid leukemia with t(16;21) chromosomal translocation.

The t(16;21)(p11;q22) translocation is a nonrandom chromosomal abnormality found in several types of myeloid leukemia, which show variable cytomorphological features. We constructed rodent-human somatic cell hybrids containing the der(16) chromosome from leukemic cells of a patient with t(16;21). Using these hybrids, we mapped the translocation breakpoint on the Not I restriction map of chromosome 21 which we had previously constructed. The result showed the proximity of the breakpoint to the ERG gene, a member of the ets oncogene superfamily. Polymerase chain reaction and Southern blot analyses of genomic DNA from the hybrids and from peripheral blood cells and bone marrow cells of patients with t(16;21) showed that the breakpoints were clustered within a single intron in the coding region of the ERG gene. This finding and the results obtained by Northern blot analysis suggested the formation of a chimeric product(s) by fusion of the ERG gene and an unknown counterpart gene on chromosome 16.

Acute Disease↗
PubMed1993

Estrogen stimulates the elaboration of cell/matrix surface-associated inhibitory factor of osteoclastic bone resorption from osteoblastic cells.

Osteoblast-like UMR106 cells secreted bone resorption-stimulating activity (BRSA) under stimulation by human parathyroid hormone 1-34. Most of BRSA was associated with cell/matrix surface and could be extracted by 2 M NaCl. Pretreatment with 17 beta-estradiol (E2) reduced BRSA by enhancing the elaboration of an inhibitory factor of BRSA in a dose-dependent manner, and 10(-9) M 17 beta-E2 showed a significant effect. Neither 17 alpha-E2 nor dihydrotestosterone showed a similar effect. The inhibitory factor of BRSA was also bound to cell/matrix surface, showed affinity for heparin, and was trypsin- and heat-sensitive. Furthermore, this factor could also inhibit resorption pit formation stimulated by 1,25-dihydroxyvitamin D3, interleukin (IL)-1 alpha and IL-6. Elaboration of such an inhibitory factor of bone resorption from osteoblasts may play an important role in the protective effect of estrogen against bone resorption.

Animals↗
PubMed1993

Changes in hematopoiesis-supporting ability of C3H10T1/2 mouse embryo fibroblasts during differentiation.

To investigate the functional change of stromal cells along with differentiation, we used a differentiation-inducible mouse embryo fibroblast cell line, C3H10T1/2 (10T1/2). Stably determined preadipocyte and myoblast cell lines were established after a brief exposure of 10T1/2 cells to 5-azacytidine. These cell lines terminally differentiated into adipocytes and myotubes, respectively, under appropriate conditions. The hematopoiesis-supporting ability of each 10T1/2-derived cell line was examined by coculture with FACS-sorted murine hematopoietic stem cells (Thy-1lo c-kit+ Lin-). The number of granulocyte-macrophage progenitors (CFU-GM) was slightly reduced after 7 days of culture with parent 10T1/2 fibroblasts, whereas a marked increase in CFU-GM number was observed when the cells were cultured on preadipocytes. Mature adipocytes and myogenically determined cell lines, on the other hand, did not support CFU-GM growth. Further, Northern analysis showed that the preadipocyte cell line acquired the ability to produce a significant amount of stem cell factor (SCF), interleukin-6 (IL-6), leukemia inhibitory factor, and macrophage colony-stimulating factor mRNAs in response to IL-1 or lipopolysaccharide stimulation. Terminal adipocytic differentiation resulted in reduced ability to express these cytokine mRNAs. Similarly, highest IL-6 activity was detected in the supernatant of preadipocyte culture, whereas adipocytes did not secrete IL-6 even after IL-1 stimulation. Interestingly, hematopoiesis-nonsupporting myoblasts and myotubes also expressed abundant SCF mRNA, suggesting that SCF, per se, may not be sufficient for stem cell growth and survival. The 10T1/2-derived cell lines could provide a valuable tool to aid in the analysis of stromal cell development and the search for novel stromal factors.

Adipose Tissue↗
PubMed1993

Effect of prostaglandin D2 on the femoral bone mineral density in ovariectomized rats.

We studied the effects of prostaglandin D2 (PGD2) on the femoral bone mineral density (BMD) and other related parameters in ovariectomized (OVx) and sham-operated rats. BMD was measured in vivo by dual energy X-ray absorptiometry (DXA) for the period of 36 days or 112 days after operation. When 9- or 10-week-old rats were used at the time of operation, the femoral BMD increased during these periods. Ovariectomy resulted in a marked suppression of this steady increase in BMD at both proximal and distal ends of the femur. Subcutaneous administration of a slow-release preparation of PGD2 on days 1 and 21 not only prevented the ovariectomy-induced suppression of BMD, but also augmented the steady increase in BMD of the sham-operated rats. When medication was started on day 70, the depressed rate of increase in BMD was restored to the control level. Serum calcitonin (CT) and parathyroid hormone (PTH) levels were not affected by either ovariectomy or by PGD2 administration. Body weight and bone length were increased, but uterine weight was decreased by ovariectomy. PGD2 administration showed no effects on these parameters. There was a significant increase in the fasting level of urinary hydroxyproline excretion after ovariectomy, and PGD2 administration had no significant effect on this parameter either. These results indicate that the prevention of osteopenia in OVx rats and the increase in BMD in sham-operated and post-OVx rats by PGD2 administration are due to its stimulatory effect on bone formation.

Absorptiometry, Photon↗
PubMed1993

DNA replication of parvovirus B 19 in a human erythroid leukemia cell line (JK-1) in vitro.

A major limitation of studies on the parvovirus B 19, a causative agent of transient aplastic crisis, has been the absence of appropriate cell lines permissive for the virus. In the present study, a human erythroid leukemia cell line (JK-1) was shown to support B 19 virus DNA replication in vitro. Forty-eight hours after virus inoculation of JK-1 liquid cell cultures, the average number of B 19 genome copies was estimated at 3,000 per cell by DNA dot blot analysis. The addition of erythropoietin increased B 19 copy number to 10,000 per cell. The presence of replicative forms of the B 19 virus genome was genome was demonstrated by Southern blot analysis. Although persistent infection of B 19 virus was not observed in JK-1 cells, this culture system will be of value in elucidating the molecular basis of the erythroid specificity of parvovirus B 19.

DNA Replication↗
PubMed1993

Sustained c-kit expression in a human erythroleukemia cell line (HEL) after megakaryocytic differentiation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA).

Changes in c-kit proto-oncogene expression were examined in a human erythroleukemia cell line, HEL, during 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced megakaryocytic differentiation. When HEL cells were treated with 10(-7) M TPA, glycophorin A expression and hemoglobin synthesis were reduced, while the expression of GP IIb/IIIa was induced in association with the morphological changes. Northern blot analysis showed that, during this megakaryocytic differentiation of HEL cells, c-kit mRNA expression persisted even after there was an apparent reduction in c-myc mRNA. This finding supports the idea that the expression of c-kit, a marker of primitive hematopoietic progenitors, may persist along with differentiation toward a megakaryocytic lineage.

Base Sequence↗
PubMed1993

Immunohistologic detection of the primary follicle (PF) in human fetal and newborn lymph node anlages.

The primary follicle (PF) emerges as a globular nest of follicular dendritic cells (FDC) and lymphocytes in the lymph node anlage in the 16th gestational week. It increases in size with age but no germinal center is found until several months later, after birth. Using a panel of monoclonal antibodies, the authors have defined phenotypes of component cells of the PF. The PF contains a B-cell population including IgM+, CD20+, CD21+, and CD24+ cells, together with a T-cell population including CD3+, CD4+, CD5+, and CD8+ but no IgG+ cells. It also contains many CD5+ B cells and several IgD+ and alkaline phosphatase-positive cells but few CD15+, CD25+, CD30+, CD38+, and Ki-67+ cells. CD24+ and dendritic reticulum (DRC)-1+ cells show an irregular meshwork pattern in the PF. CD5+ B cells appear even before the formation of the PF and increase after formation of the PF. The lymphocytic phenotype of the PF is similar to that of the mantle zone of the secondary follicle. The phenotypic characteristics indicate that the PF appears as an aggregation of CD5+ B cells and plays an important role as the ancestor of the secondary follicle as well as helper T cells and FDC.

Antigens, CD↗
PubMed1993

Analysis of the expression of seven G protein alpha subunit genes in hematopoietic cells.

Various heterotrimeric GTP-binding proteins may have important functions in hematopoietic cells. There has been no comprehensive information, however, regarding their expression in various-lineage hematopoietic cells. In this report, the expression level of seven G protein alpha subunits (Gs alpha, Gi1 alpha, Gi2 alpha, Gi3 alpha, Go alpha-1, Go alpha-2, and Gx alpha) in 13 hematopoietic cell lines were analyzed by Northern blot analysis. Gi1 alpha, Go alpha-1, Go alpha-2, and Gx alpha, were expressed in a limited number of cell lines whereas Gs alpha, Gi2 alpha, and Gi3 alpha were expressed ubiquitously in nearly all cell lines tested. Gi1 alpha was expressed selectively in a pre-T cell line, P30/PHK among lymphoid-lineage cell lines and a myeloblastic cell line, KG-1 among myelomonocytoid cell lines. Go alpha-1 was expressed only in a chronic myelocytic-leukemia cell line, K-562, whereas Go alpha-2 was not expressed in any cell lines tested after ordinary exposure of autoradiography (within 4 days). Gx alpha was expressed abundantly in a rat basophilic-leukemia cell line, RBL-2H3, and expressed in K-562. A barely detectable amount of Gx alpha messenger ribonucleic acid (mRNA) was found after a long exposure of autoradiography in several cell lines with megakaryoblastoid phenotype.

Animals↗
PubMed1993

Activin A: an autocrine inhibitor of initiation of DNA synthesis in rat hepatocytes.

The present study was conducted to examine the effect of activin A on growth of rat hepatocytes. EGF induced a 10-fold increase in DNA synthesis as assessed by [3H]thymidine incorporation in cultured hepatocytes. When activin A was added together with EGF, DNA synthesis induced by EGF was markedly inhibited. Inhibition was detected at a concentration of 10(-10) M, and 5 x 10(-9) M activin A almost completely blocked EGF-mediated DNA synthesis. Similarly, activin A completely blocked DNA synthesis induced by hepatocyte growth factor/scatter factor. Activin A was capable of inhibiting EGF-mediated DNA synthesis, even when added 36 h after the addition of EGF. With the same time interval, TGF-beta also blocked EGF-induced DNA synthesis. Although both activin A and TGF-beta inhibited growth of hepatocytes in a similar manner, either activin A or TGF-beta did not compete with each other in their binding when assessed by competitive binding using an iodinated ligand. When hepatocytes were incubated with EGF, release of bioactivity of activin A into culture medium was detected after 48 h or later. Activity of activin A was released from parenchymal cells but not from nonparenchymal cells. mRNA for beta A subunit of activin was detected only slightly in unstimulated hepatocytes, but markedly increased at 48 h after the addition of EGF. To determine whether endogenously produced activin A affects DNA synthesis, we examined the effect of follistatin, an activin-binding protein that blocks the action of activin A. An addition of follistatin significantly enhanced EGF-induced DNA synthesis. Finally, in partial hepatectomized rat, expression of mRNA for beta A subunit in liver was markedly increased 24 h after the partial hepatectomy. These results indicate that activin A inhibits initiation of DNA synthesis in hepatocytes by acting on its own receptor and that activin A acts as an autocrine inhibitor of DNA synthesis in rat hepatocytes.

Activins↗