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Biomedical subjects

F Takaku

Publications and source records attributed to F Takaku.

At least 91 records · Page 5Linked to original sources

Effects of granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor on respiratory burst activity of neutrophils in patients with myelodysplastic syndromes.

The superoxide (O2-)-releasing capacity in response to N-formyl-methionyl-leucyl-phenylalanine (FMLP) and the priming effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF) and granulocyte-macrophage colony-stimulating factor (rhGM-CSF) on FMLP-induced O2- release were investigated in neutrophils from 14 patients with myelodysplastic syndromes (MDS). The O2(-)-releasing capacity in MDS neutrophils varied from patient to patient. As compared with normal neutrophils, the O2(-)-releasing capacity in MDS neutrophils was increased in 9/14 patients, normal in three patients and decreased in two patients. There was no close relationship between the O2(-)-releasing capacity and the peripheral blood neutrophil count or the plasma concentration of C-reactive protein. The priming of neutrophils by rhG-CSF was not observed in five patients, whereas rhGM-CSF primed neutrophils from all patients. The priming effect of rhGM-CSF was consistently greater than that of rhG-CSF in each patient. The intravenous administration of rhG-CSF (300 micrograms/body) to two MDS patients showed an increase in the peripheral blood neutrophil count and enhancement of neutrophil O2- release. These findings demonstrate that the neutrophil O2(-)-releasing capacity in MDS varies from patient to patient and is not always impaired, and that rhGM-CSF is able to prime neutrophils which never respond to rhG-CSF.

Adult↗

Gene therapy.

Explore the source record for details and available documents.

Genetic Therapy↗

Irreversible suppression of CD8 expression in CD4-CD8+ thymocytes upon in vitro stimulation.

CD8 (Ly-2) expression was suppressed in purified murine CD4-CD8+ thymocytes at the mRNA level upon continuous stimulation with PMA and ionomycin in the presence of rIL-2. The level of CD8 expression on CD4-CD8+ thymocytes was reduced gradually during the culture and a majority of them turned into CD4-CD8- cells after 48 hr. This suppression was not transient, since CD8 expression was not recovered on these cells in additional 48 hr of culture without PMA and ionomycin. The suppression was dependent on the concentrations of PMA and ionomycin, and inhibited by adding an immunosuppressant, CsA to the culture. Treatment with either PMA or ionomycin alone did not induce suppression of CD8. Crosslinking of CD3-epsilon chains also induced suppression of CD8 for a part of CD4-CD8+ thymocytes. Interestingly, CD8 expression was hardly suppressed in CD4-CD8+ peripheral T lymphocytes, suggesting that the mechanisms of suppression of CD8 is developmentally regulated. We propose that the suppression of CD8 expression at CD4-CD8+ stage involves an additional mechanism of negative selection of thymic T cells.

Animals↗

[Present state and perspective of cytokine research].

Clinical usefulness of cytokines in cancer treatment has been described. Cytokines presently used in clinical practice are IFNs, IL-2, and hematopoietic growth factors. IFNs and IL-2 used with an expectation of direct antitumor effect of these cytokines have been proven to be specifically effective against certain types of tumors. Hematopoietic growth factors have been used as the adjuvant drugs in cancer treatment and proven to be effective against neutropenia and associated infections after chemotherapy and bone marrow transplantation. Future development of new cytokines and trials on the combination among cytokines and cytokines with chemotherapeutic agents, will promote the usefulness of cytokines in cancer treatment.

Antineoplastic Agents↗

Terminal deoxynucleotidyl transferase and glucocorticoid receptors in rat thymocytes.

Higher level of terminal deoxynucleotidyl transferase (TdT) and peanut agglutinin (PNA)-positive cells were found in those fractions of albumin gradient separated rat thymocytes that had a higher level of glucocorticoid (GC) receptors and a lower level of sialyltransferase (S-T) activity. Incubation of thymocytes in these fractions with dexamethasone inhibited RNA synthesis significantly. Incubation of these thymocytes with tetradecanoylphorbol-acetate (TPA) reduced TdT activity, while increasing S-T activity. The higher level of GC receptors may be responsible for GC sensitivity of TdT-positive thymocytes. In addition, sialyltransferase may be a biochemical marker for thymocyte differentiation.

Animals↗

Production of a specific monoclonal antibody to terminal deoxynucleotidyl transferase (TdT) and the extensive studies of TdT in patients with hematological malignancies.

Terminal deoxynucleotidyl transferase (TdT) was purified from calf thymus and a monoclonal antibody-producing clone was produced by the fusion of mouse myeloma cells and spleen cells of mice immunized with the purified enzyme. The antigens recognized by an immunoadsorbent column revealed TdT, whose molecular weight was 62 kDa. The extensive study of TdT in 196 patients with hematological disorders was done. The results from immunofluorescent analysis corresponded well to the results of biochemical assays of this enzyme. This monoclonal antibody will provide a useful means for the survey of leukemia and lymphoma patients.

Animals↗

[Effects of rHuEPO on aplastic anemia: results of a phase II clinical study].

The safety and efficacy of recombinant human erythropoietin (epoetin alpha) were investigated in adult aplastic anemia patients whose hemoglobin (Hb) concentration was less than 10g/dl. Epoetin alpha was given subcutaneously every day at a dose of 3,000IU/body for two weeks, and the dosage was increased to 6,000IU, 12,000IU and 24,000IU every two weeks when the increment of Hb was insufficient. In cases in whom Hb concentration increased by more than 1g/dl or whose transfusion requirements reduced to less than 50%, treatment was judged to be effective. The whole rate of efficacy was 34.5% (10/29). Response to epoetin alpha treatment was better in patients whose symptoms were relatively mild. Mild cases responded to the treatment with 6,000IU/body/day, although a dosage of 24,000IU/body/day was required in moderate or severe cases. Neither serious adverse effect nor abnormal laboratory findings were observed. These results suggest that high dose subcutaneous epoetin alpha treatment is effective for the aplastic anemia in terms of increasing Hb concentration and reducing blood transfusions.

Adolescent↗

12-0-Tetradecanoylphorbol 13-acetate (TPA)-induced enzymatic change of human non-T, non-B lymphoid leukemia cell lines.

Culture of two lymphoid leukemia cell lines with 5 x 10(-9) to 10(-7) M 12-0-tetradecanoyl-phorbol 13-acetate (TPA) induced the significant increase in sialyltransferase, acid phosphatase and butyrate esterase activities, the decrease in poly(A) polymerase and terminal deoxynucleotidyl transferase (TdT) activities. B4-, J5-, TdT- or PNA-positive cells were decreased in TPA-treated cells, while B1-positive cells were increased. These results suggest enzymatic changes as an aspect of TPA-induced differentiation in lymphoid leukemia cell lines. These enzymatic activities may be useful markers for the differentiation of lymphoid leukemia cells.

Cell Differentiation↗

[A double-blind dose ranging study of weekly subcutaneous administration of rHuEPO (KRN5702) on post-phlebotomy anemia of patients scheduled for predeposit autologous blood transfusion (multicenter late PhII study)].

Preoperative blood reservation for autologous blood transfusion generally causes anemia. We performed a double blind controlled study to determine the optimal dose of subcutaneous rHuEPO (recombinant human erythropoietin, KRN5702) for preventing preoperative anemia due to blood reservation. Patients received KRN5702 subcutaneously once a week in a doses of 12000, 24000 or 36000 IU by a double blind technique. After storage of 1200 ml of their own blood right before surgery, their hemoglobin (Hb) averaged about 1 and was about 0.5 g/dl lower than the level before administration of KRN5702 in doses of 12000 and 24000 IU, respectively. This fall was significant. In patients receiving KRN5702 in a dose of 36000 IU, the level of Hb rose instead of a fall; Hb immediately before surgery was 1.1% higher than that before administration which, however, was not significant. This elevation indicates a possibility of abnormal elevation of Hb at this dose. The mean Hb value right before surgery was significantly lower in patients receiving 12000 IU KRN5702 than in patients of the other two groups. The recovery rate of Hb was an indicator to reflect improvement of anemic conditions, and increased as the dose increased after the blood reservation. The rate in the 12000 IU group was significantly lower than that in the other two groups; there was not much difference between the other two rates. We estimated that to reserve 1200 ml of autologous blood, 24000 IU of KRN5702 is adequate but not excessive. One patient receiving 24000 IU showed side effects including an elevation of body temperature, rash, and edema.

Adult↗

[Clinical study of GM-CSF in patients with aplastic anemia and myelodysplastic syndrome. (CSF39-300 Study Group)].

We administered granulocyte-macrophage colony stimulating factor (GM-CSF) to patients with aplastic anemia and myelodysplastic syndrome (MDS), as a phase III trial. The GM-CSF was given by 3 hrs intravenous drip infusion daily for at least fourteen days. Twenty-five patients with aplastic anemia and nineteen patients with MDS were evaluable for efficacy. Peripheral blood granulocyte counts, especially neutrophil counts and eosinophil counts, increased markedly by the administration of GM-CSF in each disease. Fifteen patients with MDS and nineteen patients with aplastic anemia responded to the GM-CSF. Dose-related increase of granulocytes were seen in patients with MDS, but no relation was seen in patients with aplastic anemia. Adverse effects were observed in some patients and flu-like syndrome including fever, general fatigue and anorexia were seen most commonly but were transient. Our results showed that GM-CSF is a potent stimulator of hematopoiesis in patients with aplastic anemia and MDS.

Adolescent↗

[Clinical study of fluconazole for systemic fungal infections with hematological disorders].

Fluconazole (FLCZ) was administered orally or intravenously to 161 patients with systemic fungal infections complicated with hematological disorders and it was possible to evaluate clinical efficacies in 109 patients. Systemic fungal infections were documented in 48 patients and suspected in 61 patients. The overall clinical efficiency rates were 43.8% (21/48) in patients with documented fungal infections, and 55.7% (34/61) in patients with suspected fungal infections. Therefore, the overall clinical efficacy rate was 50.5% (55/109). Side effects were observed in 5 patients with an incident rate of 3.1% (5/161), but there was none of them was serious. These results indicate that FLCZ is an agent with good potential in treatment of systemic fungal infections in patients with hematological disorders.

Adolescent↗

Disappearance of Ph1 chromosome with intensive chemotherapy and detection of minimal residual disease by polymerase chain reaction in a patient with blast crisis of chronic myelogenous leukemia.

We diagnosed a patient with chronic myelogenous leukemia (CML) in chronic phase (CP) on the basis of clinical findings, Ph1 chromosome detected by cytogenetic analysis, and bcr-abl fusion mRNA detected by reverse transcriptase-dependent polymerase chain reaction (RT-PCR). One month after diagnosis, the patient developed extramedullary blast crisis in the lymph nodes, and then medullary blast crisis in the bone marrow, in which different surface markers were shown. Combination chemotherapy with BH-AC, VP16, and mitoxantrone was administered; this resulted in rapid disappearance of the lymphadenopathy, restoration of normal hematopoiesis, and no Ph1 chromosome being detected by cytogenetic analysis. RT-PCR performed to detect the residual Ph1 clone revealed that although the Ph1 clone was preferentially suppressed, it was still residual. The intensive chemotherapy regimen preferentially suppressed the Ph1-positive clone and led to both clinical and cytogenetic remission in this patient with BC of CML; we suggest that RT-PCR is a sensitive and useful method for detecting minimal residual disease during the clinical course of this disease.

Adult↗

[Recent trends of gene therapy of human patients].

Recent trends of gene therapy in the USA, European countries and in Japan are reviewed. Although only the gene treatment for ADA deficiency was shown to be effective, many clinical trials of gene treatment for cancer or other disorders have already been approved by the RAC of NIH. In Japan, the Ministry of Health and Welfare started to make a guide line for human somatic cell gene treatment. This guide line is expected to be publicized by the end of March of 1993. It is therefore, expected that gene treatment will start in Japan in the very near future.

Adenosine Deaminase↗

[Phase II clinical study of recombinant human erythropoietin on the anemia associated with multiple myeloma].

Safety and efficacy of recombinant human erythropoietin (epoetin alpha) were investigated in anemic patients with multiple myeloma whose hemoglobin (Hb) concentration was less than 10g/dl. Epoetin alpha (3,000IU/body) was given subcutaneously daily for two weeks and the dosage was increased to 6,000IU, 12,000IU and 24,000IU every two weeks when the increment of Hb was insufficient. Cases in which Hb concentration increased by more than 1g/dl or in which blood transfusion requirements decreased by more than 50% were judged to be effective. The overall rate of efficacy was 52.6% (10/19). Response to epoetin alpha treatment was better in patients whose blood erythropoietin level was relatively low. The majority of patients responded to the treatment with up to 6,000IU/body/day but a dosage of more than 12,000IU/body/day was required in some cases. No serious adverse effects or abnormal laboratory findings were observed. These results suggest that high-dose subcutaneous epoetin alpha treatment is effective for anemia associated with multiple myeloma in terms of increasing Hb concentration and reducing blood transfusion.

Aged↗

[Phase II clinical study of recombinant human erythropoietin on the anemia of myelodysplastic syndrome].

The safety and efficacy of recombinant human erythropoietin (epoetin alpha) were investigated in anemic patients with myelodysplastic syndrome (MDS) whose hemoglobin (Hb) concentration was less than 10g/dl. Epoetin alpha was given subcutaneously daily at a dose of 3,000IU/body for two weeks and the dosage was increased to 6,000IU, 12,000IU, and 24,000IU at two week interval when the increment of Hb was insufficient. Patients in whom the Hb concentration increased by more than 1g/dl or whose blood transfusion requirement reduced to below 50% were considered to be cases of effective treatment. The overall rate of effectiveness was 20.6% (7/34). Response to epoetin alpha treatment was better in patients with refractory anemia (RA) or RA with ringed sideroblasts (RARS). The high dose epoetin alpha (12,000-24,000IU/body/day) was required for the patients to respond. These results suggest that the high dose subcutaneous epoetin alpha treatment is effective for the anemia associated with MDS in terms of increasing Hb concentration and reducing blood transfusion.

Adolescent↗

Frequent mutations in the p53 gene in human myeloid leukemia cell lines.

The p53 gene is currently considered to function as a tumor-suppressor gene in various human malignancies. In hematologic malignancies, alterations in the p53 gene have been shown in some human leukemias and lymphomas. Although mutations in the p53 gene are infrequent in acute myelogenous leukemia (AML) patients, we show in this report that alterations in the p53 gene are frequent in myeloid leukemia cell lines. We studied alterations of the p53 gene in nine human myeloid leukemia cell lines by reverse transcriptase-polymerase chain reaction (RT-PCR), single-strand conformation polymorphism (SSCP) analysis, and direct sequencing. Expression of the p53 gene was not detected at all by RT-PCR in two of the nine cell lines. In these two cell lines, Southern blot analysis showed gross rearrangements and deletions in both of the p53 alleles. Six of the nine cell lines were found to express only mutant p53 mRNA by RT-PCR/SSCP analysis and direct sequencing, and wild-type p53 mRNA was not detected. Two of the mutant p53 mRNAs were shown to be products of abnormal splicing events induced by intronic point mutations. Taken together, eight of nine human myeloid leukemia cell lines expressed no or an undetectable amount of wild-type p53 mRNA. Three of the eight cell lines were growth factor-dependent. Our results suggest that inactivation of the p53 gene may be a common feature in myeloid leukemia cell lines and may play an important role in the establishment of these cell lines.

Base Sequence↗