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Biomedical subjects

M Kasai

Publications and source records attributed to M Kasai.

At least 253 records · Page 14Linked to original sources
PubMed1994

G-CSF mobilization in steady state for peripheral blood stem cell transplantation.

Peripheral blood stem cells were collected by granulocyte-colony stimulating factor (G-CSF) mobilization in normal volunteers and patients with hematological malignancy in complete remission without anti-cancer drug synchronization. The yields of PBSC and the possibility of G-CSF mobilization in steady state for PBSC transplantation (PBSCT) were studied. For collecting PBSC, G-CSF was subcutaneously injected at the dose of 100 micrograms/m2 on 5 consecutive days. PBSC collection was performed on day 4 and/or 5 by using cell separator, CS-3000. In normal volunteers, the yields of colony forming unit in granulocyte and macrophage (CFU-GM) was 1.9 x 10(4) kg by processing the plasma of 1.5L, and CD34 positive cell was 1.4% on the average. In patients with hematological malignancy in complete remission, the processing volume ranges from 10 to 18L/1-2 cycles, the average CFU-GM number was 2.2 x 10(5)/kg, and the average CD34 positive cell was 2.2%. In acute leukemia case, PBSCT was performed by using G-CSF mobilized PBSC, engraftment was achieved earlier. In conclusion, the yields of G-CSF mobilized PBSC from normal volunteers suggested the possibility of PBSCT and the yields of PBSC from patients in complete remission proved that G-CSF mobilization method in complete remission status could take the place of drug synchronized G-CSF mobilization for which the timing of collection and the drug choice for synchronization are intricate.

Adult↗
PubMed1994

Cytokines involved in graft-versus-host disease.

Graft-versus-host disease (GVHD) is one of the major complications which should be resolved to improve the survival rates in allogeneic bone marrow transplantation (BMT). Recently, several cytokines have been identified, suggesting that they form a cytokine network and play an important role in immune system and hematopoiesis. Among several cytokines, it has been reported that tumor necrosis factor alpha (TNF alpha) and interleukin-6 (IL-6) are mainly involved in GVHD. In the present report, we analyzed the role of cytokines in GVHD. When we measured serum cytokine levels, IL-6, interferon gamma (IFN gamma), and TNF alpha levels were increased prior to the onset of acute GVHD. For chronic GVHD, a similar pattern of cytokine increment was observed. Interestingly, these cytokines appeared to interact synergistically to induce clinical GVHD, suggesting that none of those cytokines does not function solely. Reverse transcriptase-polymerase chain reaction (RT-PCR) showed that increased IL-1 beta mRNA expression was also observed in acute GVHD in addition to increased IL-6 and TNF alpha mRNA expressions. Unexpectedly, no increased IL-2 levels were observed in both assays. In hyperacute GVHD, only IL-6 level was increased. However, in vivo administration of IL-6 into allogeneic bone marrow chimeras did not induce severe GVHD. Therefore, some other factors also appeared to be involved in inducing hyperacute GVHD. Furthermore, it is important to consider the role of inhibitory cytokines such as transforming growth factor beta (TGF beta) or IL-10.

Animals↗
PubMed1994

Cytokine gene expression by concanavalin A-stimulated peripheral mononuclear cells after bone marrow transplantation: an indicator of immunological abnormality due to chronic graft-versus-host disease.

The response of IFN-gamma, IL-2 and IL-5 mRNA expression to the stimulation of concanavalin A (Con A) in peripheral blood mononuclear cells (PBMC) after bone marrow transplantation (BMT) was analyzed using reverse-transcriptase polymerase chain reaction (RT-PCR) to assess the recovery of T cell function. The subjects were 23 patients undergoing allogeneic BMT, 1 syngeneic BMT, 1 autologous BMT and 2 normal individuals. IFN-gamma mRNA expression increased after Con A stimulation in 6 patients who had limited chronic graft versus host disease (GVHD), 14 patients who did not have chronic GVHD, each one patient receiving syngeneic and autologous BMT and 2 normal individuals. On the other hand, IFN-gamma mRNA expression was not increased by Con A stimulation in 4 patients who had extensive chronic GVHD. Also, the concentration of IFN-gamma in cultured medium in a patient with extensive chronic GVHD was not detectable. A similar low response of IL-2 and IL-5 mRNA expression to Con A was observed in these patients with extensive chronic GVHD. These findings indicate that the cytokine productive capacity of T cell (IFN-gamma and IL-2 could be produced by type 1 T helper (Th1) cells and IL-5 could be produced by type 2 T helper (Th2) cells) was suppressed in patients who had extensive chronic GVHD, while that capacity was almost normal in patients without chronic GVHD and with limited chronic GVHD. Therefore, the analysis of cytokine gene response to Con A stimulation may provide useful information regarding immune reconstitution after BMT.

Adolescent↗
PubMed1994

Hyperacute graft-versus-host disease accompanied by increased serum interleukin-6 levels.

Hyperacute graft-versus-host disease (GVHD), which progresses severely and rapidly, was observed in three patients with acute leukemia transplanted with bone marrow cells from human leukocyte antigens (HLA)-identical and mixed leukocyte reactions (MLR)-negative siblings. Hyperacute GVHD developed in these patients within 7 days after bone marrow transplantation (BMT) and was rapidly aggravated inspite of cyclosporin A (CyA) and short-term methotrexate (MTX) prophylaxis and treatment with bolus methylprednisolone (mPSL). These patients showed markedly increased serum interleukin-6 (IL-6) levels after BMT, whereas other cytokines such as interferon gamma (IFN gamma), tumor necrosis factor alpha (TNF alpha), and IL-2 were not increased compared with pretreatment levels. These findings suggest that markedly increased IL-6 levels may be related to hyperacute GVHD.

Acute Disease↗
PubMed1994

Serum cytokine levels in bone marrow transplantation: synergistic interaction of interleukin-6, interferon-gamma, and tumor necrosis factor-alpha in graft-versus-host disease.

In patients with acute graft-versus-host disease (GVHD), IL-6 gradually increased > 14 days before clinical onset of acute GVHD and decreased when acute GVHD disappeared. Interferon-gamma (IFN gamma) levels increased < 14 days before clinical acute GVHD and decreased at the disappearance of acute GVHD. Tumor necrosis factor-alpha (TNF alpha) levels increased almost simultaneously with the onset of acute GVHD and also decreased when it disappeared. However, these results do not necessarily mean that the increased levels of IL-6, IFN gamma and TNF alpha induced acute GVHD; they merely show that acute GVHD is observed more frequently in patients with increased IL-6, IFN gamma and TNF alpha levels than in those with normal levels. Although increased IL-6 levels were also observed in patients without acute GVHD, concomitant increase of IFN gamma and TNF alpha was not detected in such cases, showing that IL-6 can be increased by even graft-versus-host reaction (GVHR) which may not develop into clinical acute GVHD. Taken together, acute GVHD appeared to be induced by synergistic interaction of IL-6, IFN gamma and TNF alpha, consistent with a cytokine cascade. A similar interaction of IL-6 and TNF alpha was also observed in chronic GVHD. Although IFN gamma levels were slightly increased in chronic GVHD and sometimes aggravated the disease status, IL-6 and TNF alpha appeared to be more closely involved in the induction of chronic GVHD. In autologous BMT, increased cytokine levels were not observed unless IL-2 was administered.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1994

15-Deoxyspergualin controls cyclosporin- and steroid-resistant intestinal acute graft-versus-host disease after allogeneic bone marrow transplantation.

We report a case of cyclosporin- and methylprednisolone-resistant intestinal acute graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation which responded to a new immunosuppressant, 15-deoxyspergualin (DSG). Endoscopy showed lymphoid hyperplasia with CD3+, CD4+, CD8- lymphocyte infiltration into the submucosa of the jejunum and colon. DSG effectively suppressed this intestinal acute GVHD.

Acute Disease↗
PubMed1994

Nuclear proteins binding to a novel target sequence within the recombination hotspot regions of Bcl-2 and the immunoglobulin DH gene family.

The chromosomal breakpoints of follicular lymphomas carrying the t(14;18)(q32;q21) are known to be clustered within a 150-bp region in the major breakpoint region (mbr) of the Bcl-2 oncogene. We have demonstrated that nuclear proteins specifically bind to a novel target sequence within this 150-bp region and a region of Dxp genes, members of the immunoglobulin (Ig) diversity (DH) gene family. One protein, designated BCLF-1, appears to be specifically expressed in lymphoid lineage cells. Two other proteins, BCLF-2 and -3, bind only to the complementary single strand of the target sequence. The manner in which these proteins interact with the target sequence is similar to the interaction of the ReHF-1 and -2 proteins to the signal-like sequence at the chromosomal breakpoint junctions in patients with the t(8;14)(q24;q11) and t(1;14)(p32;q11) translocations. It was further suggested that the BCLF-1 is quite similar to or identical to the ReHF-1. It is therefore hypothesized that these conserved target sequences found in recombination hotspot regions may define novel sequence motifs recognized by two classes of DNA binding proteins. One class of DNA binding proteins is specifically expressed in lymphoid cells while the other class binds to the complementary single strand DNA. These binding activities may play a crucial role in chromosomal translocation in lymphoid neoplasms.

Base Sequence↗
PubMed1994

[Reversal of myelofibrosis is an important pre-transplant factor for bone marrow grafting--a successful case of allogeneic bone marrow transplantation for an acute megakaryoblastic leukemia].

We report a successful ereated case of acute megakaryoblastic leukemia (AMKL) with myelofibrosis (MF), which achieved a disease free condition, with disappearance of MF, for over 24 months after allogeneic bone marrow transplantation (BMT) and summarized cases of MF receiving BMT reported in Japan to evaluate the influence of MF on engraftment of bone marrow (BM). A 40-year-old man was admitted on Jan. 29, 1991 due to anemia and thrombocytopenia. BM aspiration resulted in a dry tap and MF and cells stained positive with anti-GPIIb/IIIa (CD41a) antibody were demonstrated by BM the biopsy specimen. Complete remission was achieved by multi-drug chemotherapy including behenoylcytosine arabinoside, etoposide, mitoxantrone and prednisolone (PLS). After preconditioning with little BU+CY, BMT was performed from an HLA-identical brother on Jan. 16, 1992. From day 9 of post BMT, acute skin graft versus host disease (grade 1) was observed, which was controlled by 60 mg/day of PSL. Engraftment was achieved on day 12. Although cystitis developed, he was discharged on Apr. 5, 1992 and remains disease free. Including the present case, seven allogeneic BMT patient with MF have been reported so far in Japan. Four cases in whom MF recovered before BMT showed better results than other three cases that still showed MF at BMT. Reversal of MF seems to be a favorable pre-transplant factor for successful BMT in patients with MF.

Adult↗
PubMed1994

[Clinical application of gene technology to monitor bone marrow transplantation].

We assessed the origin of peripheral blood cells and bone marrow cells obtained from 15 patients after allogeneic bone marrow transplantation (allo BMT) by sensitive two-step polymerase chain reaction (PCR) amplification of MCT118, a variable number of tandem repeats regions (VNTR), that can be used to detect the DNA pattern of a minor cell population of only 1% without using radioisotopes. Mixed chimerism(MC) was detected in the haematopoietic cells of 3 patients. Two patients developed relapse of leukaemia after the detection of MC and one patient died of bone marrow hypoplasia 7 months after BMT. These findings indicate the clinical usefulness of this method to monitor patients with MC. Also, we analyzed cytokine gene expression in peripheral blood mononuclear cells during the development of graft-versus-host disease (GVHD) in patients who underwent allo BMT using a semiquantitative reverse-transcriptase polymerase chain reaction (RT-PCR). The expression of interleukin(IL)-1 beta, IL-6, and tumor necrosis factor (TNF)-alpha mRNA was increased during the development of GVHD and the degree of this increment depended on the severity of the disease. These findings suggest that IL-1 beta, IL-6, and TNF-alpha produced by peripheral blood mononuclear cells play an important role in the development of GVHD. Therefore, analysis of MC and cytokine mRNA expression using the PCR technique after allogeneic bone marrow transplantation provide important information for treatment and monitoring of marrow transplant patients.

Adolescent↗
PubMed1993

Effects of a protein-free diet or food restriction on the immune system of Wistar and Buffalo rats at different ages.

The effects of a protein-free diet or food restriction on the immune system were examined in two rat strains, Wistar and Buffalo, in different age-groups. Unlike Wistar rats, Buffalo rats have an unusually hyperplastic thymus and a large number of peripheral T cells. The protein-free diet (PFD) in rats resulted in marked thymic involution together with a reduction of splenic T cells, both in number and in antibody response to sheep red blood cells. The depressive effect of the PFD on the immune system was more serious in young immature rats than in older rats, but less serious in Buffalo rats having enhanced T cell functions regardless of age. Thymic involution was also accelerated in both strains of rats by feeding them a restricted amount of the control diet containing well-balanced nutrients (food restriction, FR). In the FR experiment, no significant change was observed in immune functions of Wistar rats. A slight reduction was observed in the immune functions of Buffalo rats with FR, but absolute levels were distinctly higher in Buffalo rats than in Wistar rats even after FR. These results suggested (1) that the thymic function is sensitive to protein deficiency; (2) that a well-balanced dietary condition is necessary for immunological maturation in the early stage of life and preservation of immune functions at older age; (3) that animals having higher immune functions are more resistant to malnutrition than ordinary ones.

Aging↗
PubMed1993

Influence of the mucin coat on the survival of rabbit and mouse embryos stored at 0 degrees C.

To examine the factors affecting the survival of refrigerated embryos, rabbit and mouse morulae were stored at 0 degrees C in modified phosphate-buffered saline (PB1) or in PB1 containing 0.75 M sucrose. Survival was defined as the ability to develop into an expanded blastocyst in culture. The data was analyzed with special reference to the presence of a mucin coat around the embryos. When rabbit morulae were stored in isotonic PB1 for 2, 4, 6, and 8 days, survival rates were 98%, 88%, 85%, and 50%, respectively. However, if the mucin coat had been removed before storage, the rates were lower (95%, 75%, 36%, and 3%, respectively). Sucrose impaired the survival of rabbit morulae irrespective of the presence of the mucin coat. Only 11% of mouse morulae survived 2 days of storage in PB1 medium, but if the medium contained sucrose, survival rates after storage for 2, 3, 4, and 5 days were higher (83%, 55%, 31%, and 7%, respectively). To provide them with a mucin coat around the zona pellucida, mouse embryos were incubated in a rabbit oviduct. Survival rates of these embryos after storage in the presence of sucrose did not decrease over 4 days of refrigeration (98-92%), and the rates after storage for 5, 6, and 7 days were 65%, 40%, and 30%, respectively; embryos that had been stored for 5 days were transferred to recipient mice, and live young were born. Agar embedding of mouse morulae did not have the same effect as the mucin coat.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Adducts of mitomycin C and DNA in EMT6 mouse mammary tumor cells: effects of hypoxia and dicumarol on adduct patterns.

6-CH3-3H-Mitomycin C (MC) was used to identify MC-DNA adducts formed in EMT6 mouse mammary tumor cells. DNA was isolated from cells treated with 3H-MC. The DNA was enzymatically digested, and the digest was analyzed for 3H-labeled adducts by high performance liquid chromatography. All four major adducts previously isolated and characterized in cell-free systems were detected: two different monoadducts and two bisadducts forming DNA-interstrand and DNA-intrastrand cross-links, respectively. No MC-DNA adducts other than the DNA interstrand cross-link had been shown previously to be formed in living cells. A MC-deoxyguanosine adduct of unknown structure was also detected in DNA from EMT6 cells; this adduct was also formed with purified EMT6 DNA. High performance liquid chromatography analysis was further applied to study the relationship between DNA adducts and cytotoxicity. The number of adducts increased with the concentration of MC in both aerobic and hypoxic cells. At a constant drug level, more adducts were observed in cells treated under hypoxic conditions than in cells treated aerobically; at 2 microM MC, 4.8 x 10(-7) and 3.1 x 10(-7) adducts/nucleotide were observed under hypoxic and aerobic conditions, respectively. The increased adduct frequency under hypoxia correlates with the known increased cytotoxicity of MC to EMT6 cells under hypoxic conditions. In addition, a higher ratio of cross-linked adducts to monoadducts was observed in hypoxic cells. The high performance liquid chromatography techniques were also used to examine the effects of dicumarol (DIC) on adduct patterns in cells treated simultaneously with 3H-MC. The MC-DNA adduct frequencies in DIC-treated cells were increased 1.5-fold under hypoxia and decreased 1.6-fold under aerobic conditions from those observed without DIC. This finding correlates with the known DIC-induced increase and decrease in the cytotoxicity of MC in hypoxic and aerobic EMT6 cells, respectively. The monoadduct resulting from monofunctionally activated MC was suppressed by DIC under both hypoxic and aerobic conditions. In addition, DIC induced the selective formation of an unknown DNA-associated radiolabeled substance in hypoxic cells; this is hypothesized to be a cytotoxic DNA lesion produced by a DIC-stimulated oxido-reductase. The methodology developed to measure MC adduct patterns may be useful as an indicator of distinct enzymatic activation processes for this drug.

Aerobiosis↗
PubMed1993

Induction of protein-DNA complexes in HeLa S3 cells by KW-2149, a new derivative of mitomycin C.

KW-2149 is a new water-soluble analogue of mitomycin C which shows a broad spectrum antitumor activity in experimental tumor models including mitomycin C-resistant tumors and is less hematotoxic than mitomycin C. We have found that KW-2149 increases protein-DNA complexes in HeLa S3 cells using the potassium/sodium dodecyl sulfate precipitation method which recovers largely DNA bound covalently to protein but does not precipitate DNA bound noncovalently to proteins. In contrast, no increase of the protein-DNA complexes are shown in cells treated with mitomycin C. Thus, KW-2149 binds covalently with both DNA and protein, and this may mediate for KW-2149 the potent and characteristic antitumor activity compared with mitomycin C.

Antineoplastic Agents↗
PubMed1993

Synapse formation in dissociated cell cultures of embryonic chick cerebral neurons.

The development of synapses was confirmed in the primary cultures of dissociated cerebral cortex neurons from chick embryos. Whole-cell patch clamp recording applied to dissociated neurons from 6- to 12-day-old embryos revealed that these neurons form functional synapses. In these cultures, both excitatory and inhibitory postsynaptic responses were observed. Synaptogenesis in our cultures seemed to be in proportion to the embryonic equivalent days, which are the sum of the days in incubation and culture.

Animals↗
PubMed1993

Channel opening process is responsible for the slow component in the flux measurement of membrane vesicles.

The time course of tracer ion efflux from vesicles of uniform size, each of which contains an ion channel was theoretically analyzed. It is shown that the apparent flux rate reflects the opening rate of the channel when the flux rate is much higher than the channel gating rates. The theory was also developed for the system of vesicles whose volume is changed by an osmotic pressure jump with permeable solutes. The theory was applied to analyze the results obtained from ion flux measurements with sarcoplasmic reticulum vesicles, where ion fluxes through anion and cation channels have been observed by the tracer method, the volume change-light scattering method and the fluorescence quenching method. The results were successfully interpreted with the present model referring to the results from the electrical single channel recordings.

Fluorescence↗