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Biomedical subjects

S Furusawa

Publications and source records attributed to S Furusawa.

At least 73 records · Page 4Linked to original sources
PubMed1996

Effects of antitumor activity and protection of shock symptoms by a traditional Chinese medicine (sho-saiko-to) in recombinant human tumor necrosis factor administered mice.

The effects of a traditional Chinese medicine Sho-saiko-to (Kampo prescription) were investigated on the various metabolic disorders and antitumor activity of recombinant human tumor necrosis factor (rhTNF) administered to mice. The glycogen level in liver of rhTNF (5 x 10(4) units/mouse, i.v.)-injected mice was markedly lower at 4 h post-intoxication than that in the control, whereas the administration of rhTNF to Sho-saiko-to (500 mg/kg/d, p.o.)-pretreated mice resulted in a greater level of glycogen than that in rhTNF alone-treated mice. In mice pretreated with Sho-saiko-to, the level of fibrinogen 4 h after rhTNF injection markedly increased as compared to that in mice treated with rhTNF alone. We also estimated the NO2 in murine macrophage cell line J774A.1 using mice serum after administration of Sho-saiko-to. Our results clearly demonstrated that J774A.1 cells stimulated with endotoxin (1 micrograms/ml) and rhTNF (1 x 10(4) units/ml) can effectively produce nitric oxide (NO), and ascertained the suppressive effect of Sho-saiko-to (500 mg/kg/d, p.o)-pretreated serum on NO generation by endotoxin/TNF-activated J774A.1 cells. When the cells were incubated with endotoxin/TNF and Sho-saiko-to pretreated serum (10-100 microliters), the NO level was significantly lower than that in control serum incubated with endotoxin/TNF alone. The effect of Sho-saiko-to (1 and 10 micrograms/ml) on in vitro cytotoxicity by rhTNF in Meth-A Sarcoma cells was observed to be in a dose dependent fashion. In addition, there was a remarkable enhancement of antitumor activity of rhTNF by Sho-saiko-to pretreatment in mice. These findings suggest that the Kampo prescription Sho-saiko-to may protect mice from severe shock syndrome by rhTNF, and that it may enhance rhTNF-induced activity.

Animals↗
PubMed1996

[Studies on reversing effect of multidrug resistance by dipyridamole. I. modulation of epirubicin-induced effects on cell proliferation and cell cycle by dipyridamole].

Dipyridamole, a nucleoside membrane transport inhibitor, enhanced the cytotoxicity of epirubicin for mouse leukemia P388 cells by a factor of 1.8-fold and that for 30-fold doxorubicin-resistant sublines of P388 cells (P388/DOX) by a factor of 6.5-fold. This interaction was shown to be truly synergistic by DNA histogram and median effect analysis. The dipyridamole enhancement of the cytotoxicity of epirubioin was a dose-dependent effect; it was greatest when cells were exposed to dipyridamole before treatment with epirubicin. In cell cycle experiments, 1-5 microM dipyridamole increased the accumulation of G2 + M phase produced by the treatment with 0.5-1 microM epirubicin. Dipyridamole, however, did not appear to alter the patterns of DNA histogram in sensitive cells. These results suggest that the increase of the accumulation of G2 + M phase in resistant cells is an important factor for the interaction between epirubicin and dipyridamole.

Animals↗
PubMed1996

[Studies on reversing effect of multidrug resistance by dipyridamole. II. Inhibition of epirubicin efflux from resistant cells by dipyridamole and its pharmacological effect].

We have previously reported that dipyridamole increases the cytotoxicity of epirubicin and alters the cell cycle in doxorubicin-resistant (P388/DOX) cells, increasing the accumulation of G2/M phase by blocking the cell cycle. In cultured cells, dipyridamole increased dose-dependently the intracellular accumulation of epirubicin in the resistant cells. Simultaneous exposure of the resistant cells to epirubicin and 100 microM dipyridamole resulted in a 4.2-fold increase in proportion to the control level of epirubicin after 60 min. Dipyridamole inhibited the enhanced efflux of epirubicin in doxorubicin-resistant cells. However, dipyridamole had no effect on both the influx and efflux of epirubicin in doxorubicin-sensitive cells. In mice, lethal and bone marrow toxicity induced by epirubicin were potentiated by administration of high-dose of dipyridamole. In addition, in vivo results also demonstrated that dipyridamole in combination with epirubicin produced a significant reversal of the in vivo antitumor activity of epirubicin in mice bearing P388/DOX cells. These data imply the enhancement effects of dipyridamole on the efficacy and toxicity of epirubicin.

Animals↗
PubMed1996

Two chicken B cell lines resistant to ouabain for the production of chicken monoclonal antibodies.

Two chicken B cell lines, termed MuH1 and MuH4, which are resistant to ouabain, were established as fusion partners for production of chicken monoclonal antibody from the parental cell lines R27H1 and R27H4 which were deficient in thymidine kinase activity. The MuH1 synthesized, but did not secrete mu chain, whereas the MuH4 secreted non-specific IgM. Fusions of the MuH1 and MuH4 with spleen cells from chickens immunized with human IgG resulted in successful preparations of hybridomas secreting antibodies specific to human IgG. Transformed cells insensitive to HAT appeared in many culture wells after cell hybridizations with R27H4, but on hybridization with MuH1 or MuH4 the appearance of such unfavorable cells could be avoided by the inclusion of ouabain in HAT medium. Thus, in comparison with the R27H4 line, the MuH1 and MuH4 lines did not provide higher fusion efficiencies, but gave increased opportunities to obtain hybridomas producing specific antibodies. Among a total of eight hybridomas, four derived from HuM1 and four derived from MuH4, seven secreted both IgG and IgM, and the remaining one derived from MuH1 secreted only IgG. In all eight hybridoma lines IgG was specifically reactive to human IgG.

Animals↗
PubMed1996

Production and characterization of polyclonal anti-canine interleukin-8 antibodies.

Polyclonal anti-canine interleukin-8 (cIL-8) antibodies were raised in rabbits immunized with cIL-8 expressed by E. coli. Polyclonal antibodies were purified by affinity chromatography. In the enzyme linked immunosorbent assay (ELISA), the resulting anti- cIL-8 antibodies showed relatively high reactivities with cIL-8 in the fusion proteins of glutathione-S-transferase/cIL-8 (GST/cIL-8) and maltose binding protein/cIL-8 (MBP/cIL-8), but negligible ones with MBP. Furthermore, Western blotting analysis using these polyclonal antibodies showed distinct bands for cIL-8, GST/cIL-8, and MBP/cIL-8. These antibodies also bound to recombinant human IL-8 (rhIL-8) in ELISA but not in Western immunoblotting. The rHIL-8 (50-800 ng/ml) was chemoattractant for canine neutrophils in a dose dependent manner, but the anti-cIL-8 antibodies did not show the inhibitory effect on the chemotactic activity of rhIL-8 of canine neutrophils, when tested by the chemotaxis assay using Boyden chambers. In addition, GST/cIL-8 and rhIL-8 induced strong and rapid shape change responses of canine neutrophils. However, the anti-cIL-8 antibodies inhibited shape change responses induced by GST/cIL-8 but not by rhIL-8.

ATP-Binding Cassette Transporters↗
PubMed1996

One case of pemphigus vulgaris observed in the oral cavity.

We report on a case of pemphigus vulgaris with lesions in the oral cavity as well as an outline of differential diagnosis and treatment. Changes in the pemphigus antibodies in blood assisted in judging the therapeutic effects along with the therapeutic course.

Adult↗
PubMed1996

Internal DNA deletion within the BCL-6 gene on untranslocated chromosome in non-Hodgkin's lymphoma with 3q27 abnormality.

Chromosomal translocations involving the band 3q27 are recognized as common specific cytogenetic abnormalities in B cell non-Hodgkin's lymphoma (NHL), and the BCL-6 gene, identified on 3q27 was shown to be disrupted by these translocations. Previously, we have reported biallelic BCL-6 rearrangements occurring in some patients with B cell NHL. In the present study, we describe a NHL patient with t(3;22)(q27;q11) translocation. In this patient, biallelic BCL-6 abnormalities were indicated by Southern blot analysis. Further studies revealed that one of the two independent abnormalities was a juxtaposition to the immunoglobulin (Ig) lambda gene associated with chromosomal translocation, whereas the other was an internal DNA deletion of 1.5 kb area on untranslocated chromosome 3. Deletion junctions were located within the first exon and the 5' region of the first intron. The result provides the evidence that, besides chromosomal translocation, submicroscopic local DNA recombination can cause structural alteration of the BCL-6 gene.

Base Sequence↗
PubMed1996

Augmentation of epirubicin cytotoxicity by cycloheximide.

The effect of cycloheximide (CH) on the cytotoxic activity of the anthracycline antibiotic epirubicin (EPI) was examined in cell cultures of murine leukemia doxorubicin (DOX)-sensitive P388 and -resistant P388 cells. The addition of CH (0.002 mu g/ml) to the growth medium markedly enhanced the EPI-induced cytotoxic effect in sensitive cells as well as that observed in resistant cells. CH, however, did not affect the intracellular content of EPI. The inhibition of DNA synthesis in leukemia cells was remarkable with the combination of EPI and CH compared with each drug alone. These results suggest that the combination of EPI and CH appears to be useful in killing mouse leukemia cells.

Animals↗
PubMed1996

Reversal of multidrug resistance by tacrolimus hydrate.

Tacrolimus hydrate, a potent immunosuppressant produced by Streptomyces tsukubaensis, was examined for its effect on epirubicin activity in multidrug-resistant P388 leukemia (P388/R) cells overexpressing P-glycoprotein and the parent (P388/S) cells. In the absence of modulator, the 50% inhibitory concentration for epirubicin after 48-h incubation, determined using a microculture tetrazolium assay, was 0.8 microgram/ml in P388/R cells and 0.009 microgram/ml in P388/S cells. P388/R cells demonstrated a 90-fold reduction in sensitivity to epirubicin. Tacrolimus hydrate (1 and 10 microM) markedly enhanced epirubicin cytotoxicity by 4.2- and 26.7-fold for P388/R cells. A significant increase in LDH release from cells by tacrolimus hydrate was also observed in P388/R cells treated with epirubicin. Tacrolimus hydrate had a marked effect on epirubicin-induced G2/M blockade in the resistant cells. Both tacrolimus hydrate and cyclosporin A dramatically increased the accumulation of epirubicin by the resistant cells, while these compounds had no effect on epirubicin accumulation in the parent cells. Thus, tacrolimus hydrate is able to down-modulate P-glycoprotein-associated resistance through inhibition of P-glycoprotein function, suggesting that the drug may be a candidate for killing drug-resistant tumor cells.

Animals↗
PubMed1995

Biallelic DNA rearrangements and deletions within the BCL-6 gene in B-cell non-Hodgkin's lymphoma.

Chromosomal translocations involving band 3q27 are recently described common specific cytogenetic abnormalities in B-cell neoplasms, and the BCL-6 gene, identified on 3q27, was shown to be disrupted and over-expressed in lymphoma cells having these chromosomal translocations. In the present study we found rearrangements within the BCL-6 gene in seven out of 35 cases with B-cell non-Hodgkin's lymphoma (NHL). Further analysis revealed that three of these patients with BCL-6 abnormality had multiple rearranged bands hybridized with probes from a single restriction fragment within the major translocation cluster (MTC), suggesting that independent DNA rearrangements would occur on both alleles. Additionally, Southern blot analysis indicated that three patients carry deletions encompassing the area containing the first exon of the BCL-6 gene. Our results suggest that biallelic DNA rearrangements and deletions would occasionally occur in NHL patients with BCL-6 abnormality.

Adult↗
PubMed1995

Inhibition of doxorubicin-induced cell death in vitro and in vivo by cycloheximide.

We studied the effects of the protein synthesis inhibitor, cycloheximide (CH), on cell killing by doxorubicin (DOX) in vitro and in vivo. At the concentration of CH used (1 microgram/ml) the cytotoxicity of DOX was reduced in cultured P388 leukemia cells. An analysis of the DNA histogram obtained by flow cytometry showed that DOX exerts its growth-inhibitory effect by blocking the cell cycle at the G2/M phase in P388 cells. Treatment with CH diminished this blocking effect. When CH was added to the growth medium before DOX exposure, no change in intracellular DOX accumulation was observed. Treatment with CH (15 mg/kg) significantly diminished the lethality of DOX (20 mg/kg) in mice and it also reduced the antitumor activity of mice with P388 leukemia. Thus, CH inhibited cell death induced by DOX in vitro and in vivo. These results suggest that CH has an antagonistic effect on the pharmacological actions of DOX in cells and mice. The cytoprotective effect of CH may be due to protein synthesis inhibition.

Animals↗
PubMed1995

Depressive effect of a traditional Chinese medicine (sho-saiko-to) on endotoxin-induced nitric oxide formation in activated murine macrophage J774A.1 cells.

The present study investigated whether or not Sho-saiko-to (crude powder extract, TJ-9) can suppress nitric oxide (NO) generation by endotoxin-activated J774A.1 cells in order to study the preventive mechanism of Sho-saiko-to against endotoxemia. In this experiment, we estimated the NO2- in the murine macrophage cell line J774A.1 using the Griess method. Our results clearly demonstrated that J774A.1 cells stimulated with endotoxin (0.01-10 micrograms/ml) can effectively produce NO, and the production was dependent on the dose of endotoxin. On the other hand, we investigated the suppressive effect of TJ-9 (10-100 micrograms/ml) on NO generation by endotoxin (0.1 microgram/ml)-activated J774A.1 cells. The NO level when the cells were incubated with endotoxin and TJ-9 (10-20 micrograms/ml) was slightly lower than that in cells treated with endotoxin alone. In contrast, treatment with TJ-9 (50-100 micrograms/ml) significantly inhibited endotoxin-activated NO generation in J774A.1 cells, whereas the treatment with TJ-9 (10-100 micrograms/ml) alone was ineffective in inducing NO formation and in inhibiting cell viability in the J774A.1 cells. These findings suggest that a Kampo presciption of Sho-saiko-to shows a suppressive effect on NO generation in macrophages stimulated with endotoxin, and that it may be useful in improving endotoxin-shock symptoms.

Animals↗
PubMed1995

Effects of 6-Hydroxydopamine on the antibody response to the hapten dinitrophenyl in the chicken.

Antibody responses to the hapten dinitrophenyl (DNP) and the concentration of catecholamine in chickens received a single injection of 6-Hydroxydopamine (6-OHDA) into the chorioallantoic cavity at the embryonal stage were evaluated. A significantly enhanced anti-DNP IgA response and a markedly decreased level of noradrenaline in the peripheral blood were observed in chickens treated with 400 micrograms of 6-OHDA at 14 days of incubation. These results suggested the immunomodulatory influence of the sympathetic nervous system.

2,4-Dinitrophenol↗
PubMed1995

Flow cytometric analysis and immunohistochemistry of delayed-type hypersensitivity responses in mice immunized with rat hepatocytes.

Delayed-type hypersensitivity (DTH) responses to rat hepatocytes (HCs) in mice were investigated by flow cytometric analysis and immunohistochemistry with monoclonal antibodies directed against murine class II, CD4, and CD8 antigens. Mice were immunized subcutaneously (s.c.) with 10(6) rat HCs (referred to as s.c.-immunized mice), and control mice were injected s.c. with sterile Hanks' solution (non-immunized mice). Four days later, 10(5) rat HCs were injected into the footpad of s.c.-immunized mice and non-immunized mice. The DTH response in s.c.-immunized mice significantly increased after challenge when compared to that in non-immunized mice. The numbers of class II+, CD4+, and CD8+ cells in the footpad, and CD4+ and CD8+ cells in the inguinal lymph node of s.c.-immunized mice significantly increased during the DTH response. An increase in the number of CD4+ cells in the footpad of s.c.-immunized mice after challenge was more significant than that of non-immunized mice. The number of CD4+ cells increased more markedly in the footpad of s.c.-immunized mice as compared to that of CD8+ cells. Furthermore, immunohistochemical studies of the footpad of s.c.-immunized mice showed more severe infiltration of CD4+ cells rather than CD8+ cells at the injection site of rat HCs. These results suggest that the DTH response in the footpad of mice immunized with rat HCs is associated with severe infiltration of CD4+ cells.

Animals↗
PubMed1995

Detection of the chemotactic factor for canine peripheral blood mononuclear cells and polymorphonuclear cells in the culture supernatant of Cos7 cells transfected with canine interleukin-8 cDNA.

Chemotactic activities in the culture supernatants of Cos7 cells transfected with a cloned canine IL-8 cDNA (pcIL-8SR alpha 14) were evaluated by using mononuclear cells (MNC) and polymorphonuclear cells (PMN) from the peripheral blood of dogs. The culture supernatants of Cos7 cells were collected 66 hr after the transfection of pcIL-8SR alpha 14 (Cos7/cIL-8). Chemotactic activities in the culture supernatants for MNC and PMN were determined as migration distances in Millipore membrane filters in a modified Boyden's chamber method. Peroxidase staining for MNC was effective not only for cells in cytospun smears but also for cells migrated in the filters. PMN in cytospun smears were well stained by peroxidase staining, whereas migrated PMN in the filters were stained weakly. Chemotactic activities in the culture supernatant of Cos7/cIL-8 cells for both MNC and PMN were significantly higher than those of control Cos7 cells. In addition, the culture supernatant of Cos7/cIL-8 cells was chemotactic for peroxidase negative nonadherent MNC (lymphocytes), but not for peroxidase positive adherent MNC (monocytes). This Cos7/cIL-8 supernatant also showed chemotactic activities for neutrophils in a dose dependent manner. These results suggest that the culture supernatant of Cos7/cIL-8 is chemotactic for lymphocytes as well as for neutrophils.

Animals↗
PubMed1995

Enhancing effects of chicken egg white derivatives on the phagocytic response in the dog.

Immunostimulative effects of chicken egg white derivatives (EWD) on phagocytic responses of peripheral blood mononuclear cells (MNC) and polymorphonuclear cells (PMN) in dogs were evaluated by flow cytometric analysis. Peripheral blood leukocytes (PBL) cultured with EWD showed the enhanced phagocytic response. The response was maximal when PBL were cultured with 100 - 400 micrograms/ml of EWD for 3 - 12 hr. Furthermore, significantly increased phagocytic responses were also induced even when PBL were cultured with protein components (200 micrograms/ml) of EWD such as conalbumin, flavoprotein and ficin-papain inhibitor for 3 hr. In addition, the enhancing effect of EWD on the phagocytic responses was also observed in MNC cultured with EWD (200 micrograms/ml) for 4 hr but not in PMN cultured with EWD in the same procedures. The supplement of the supernatant (20%) of MNC cultured with EWD (200 micrograms/ml) for 24 hr at 37 degrees C to PBL and MNC resulted in the enhancement of their phagocytic responses. In contrast, the supernatant of PMN cultured with EWD for 24 hr at 37 degrees C did not show any significant enhancing effect on the phagocytic responses of PBL, MNC and PMN. These results suggest that EWD has an enhancing effect on phagocytosis of MNC and PMN, which may be mediated through active humoral substances produced by EWD-stimulated MNC.

Adjuvants, Immunologic↗