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Biomedical subjects

R Ohno

Publications and source records attributed to R Ohno.

At least 235 records · Page 13Linked to original sources
PubMed1993

Nucleotide sequences of the variable regions of a human monoclonal antibody against HLA-A1, A23, and A24.

Nucleotide sequences of the heavy and light chain variable (VH and VL) regions of a human monoclonal antibody (4-35-7), which recognized HLA-A1, A23 and A24, were determined by means of the reverse transcriptase-polymerase chain reaction. This antibody was generated by Epstein-Barr virus transformation of lymphocytes obtained from a multiparous donor, followed by fusion with mouse myeloma cells. The VH gene segment belonged to the VHIII gene family, and used the DXP4 and JH4 gene segments. This VH gene segment had 92.9% homology to the germline gene VH26, and contained 21 nucleotide substitutions. Fourteen of them generated the replacements of amino acids, while 7 failed to generate the replacement. The ratio of replacement to silent mutations in complementarity determining regions (CDRs) was 7.0. The VL gene segment belonged to the VkI gene family, and used Jk4. This VL gene segment showed 96.1% homology to the germline gene HK102, and contained 11 nucleotide substitutions. Seven of them generated the replacement of amino acids, while 4 failed to generate the replacement. The high ratio of replacement to silent mutations in CDRs of the VH gene segment suggested that the multiparity caused the processes of antigenic selection and somatic mutation, and generated this anti-HLA antibody.

Amino Acid Sequence↗
PubMed1993

G-CSF in the treatment of acute myeloid leukemia: is it safe?

Recent studies of granulocyte colony stimulating factor (G-CSF) in the treatment of myeloid leukemia in Japan have revealed that: 1) G-CSF accelerates neutrophil recovery significantly after intensive chemotherapy or bone marrow transplantation (BMT); 2) G-CSF decreases the number of febrile days and the incidence of documented infections; 3) daily administration of G-CSF, starting from two days before chemotherapy or starting from two days after the end of chemotherapy, tended to increase the remission rate; 4) there is no evidence of stimulation by G-CSF of the growth of myeloid leukemia cells if it is used for a short period of time and if the number of leukemic cells is highly reduced by chemotherapy; 5) there is no evidence that G-CSF administration increases relapse rates of leukemia after chemotherapy or BMT. However, until further randomized studies answer these questions, caution must be exercised to avoid unnecessary stimulation of neutrophil production, and G-CSF should not be given to myeloid leukemia patients with a large number of leukemic cells left.

Bone Marrow Transplantation↗
PubMed1993

Autologous BMT in high risk patients with CALLA-positive ALL: possible efficacy of ex vivo marrow leukemia cell purging with monoclonal antibodies and complement.

Autologous BMT (auto-BMT) has been conducted for 17 high-risk common ALL antigen (CALLA)-positive non-T cell type ALL patients. Ex vivo purging of leukemia cells from infused BM cells was performed using complement and three kinds of mouse monoclonal antibodies reactive to CALLA-positive leukemia cells: NL-1 (IgG2a), NL-22 (IgM), and HL-47 (IgM). Minimal residual leukemia cells in BM were examined by PCR method in Philadelphia chromosome (Ph1)-positive ALL cases. BCR/ABL chimeric transcript, which was positive in BM samples before purging, was shown to be absent after ex vivo purging in all three cases tested. Among four Ph1-positive cases transplanted in first CR, three cases survived in CR remission 77, 29 and 26 months after BMT, and one case died without relapse 4 months after BMT. The other four Ph1-negative cases transplanted in the first CR also remained in CR except one who relapsed. The results of minimal residual leukemia cell studies and clinical data indicate the effectiveness of our ex vivo leukemia cell purging method and auto-BMT in the early stage of CR for patients with high risk ALL.

Adolescent↗
PubMed1993

A randomized controlled study of granulocyte colony stimulating factor after intensive induction and consolidation therapy in patients with acute lymphoblastic leukemia. Japan Adult Leukemia Study Group.

To determine the efficacy and optimal daily dose of recombinant human granulocyte colony-stimulating factor (rG-CSF) after intensive chemotherapy, a prospective randomized study was conducted with daily intravenous administration of 2, 5 or 10 micrograms/kg G-CSF after induction therapy, and 0, 2, 5 or 10 micrograms/kg after consolidation therapy, until neutrophil counts recovered to more than 2000/mm3. The subjects were 41 adult patients with newly diagnosed acute lymphoblastic leukemia (ALL). After the induction therapy, neutrophil recovery to more than 1000/mm3 was significantly faster in the 5 (P = 0.047) and 10 micrograms/kg groups (P = 0.011) than in the 2 micrograms/kg group, but did not differ between the 2 former groups. The median days of neutrophil recovery to more than 1000/mm3 were 8.5, 9 and 12 days, respectively. After the consolidation therapy, neutrophil recovery to more than 1000/mm3 was significantly faster in the 2, 5 and 10 micrograms/kg groups than in the no rG-CSF group (P < 0.001, respectively), but did not differ among the 3 former groups. The median days of neutrophil recovery to more than 1000/mm3 were 12, 11, 10, and 23 days, respectively. Febrile neutropenia and incidence of documented infection tended to be less in the 5 and 10 micrograms/kg groups than in 0 and 2 micrograms/kg groups. A dose of 5 micrograms/kg rG-CSF given by a 30 min infusion daily seems to be an effective and optimal daily dose to accelerate neutrophil recovery after intensive remission induction and consolidation chemotherapy in adults with acute lymphoblastic leukemia (ALL).

Adolescent↗
PubMed1993

[Effective methyl prednisolone pulse therapy for a patient with retinoic acid syndrome in acute promyelocytic leukemia].

A 46-year-old woman with acute promyelocytic leukemia (APL) was treated with all-trans retinoic acid (ATRA) and chemotherapy according to the AML-92, M3 regimen of the Japan Adult Leukemia Study Group (JALSG). Between days 7 and 18 of therapy, she suffered chest discomfort, fever, cough, dyspnea and general fatigue. A chest roentogenogram showed bilateral interstitial infiltrates. Her leukocyte count began to increase rapidly to 6,400/microliters on day 14. Marked hypoxia (PO2 35.9 mmHg) suggested occurrence of retinoic acid (RA) syndrome. She underwent endotracheal intubation and mechanical ventilation with administration of methyl-prednisolone (m-PSL) pulse therapy. Her symptoms promptly abated. Therapy with ATRA was continued and her leukocyte count reached 44,800/microliters on day 19 of therapy. She achieved complete remission on day 48.

Dyspnea↗
PubMed1993

[A "retinoic acid syndrome" observed in two cases of acute promyelocytic leukemia].

Two cases of acute promyelocytic leukemia (APL) treated with all-trans retinoic acid (ATRA) developed fever, dyspnea and chest pain. A chest roentgenogram showed bilateral pleural effusion (case 1) and bilateral interstitial infiltration (case 2). The first case was a 50-year-old female in her first relapse, who was initially diagnosed as having pleuritis tuberculosa and was treated with anti-tuberculotic agents. Her symptoms continued for 44 days and complete remission was achieved 53 days after commencing ATRA therapy. The second case was a previously untreated 46-year-old male. His case had been diagnosed as adult respiratory distress syndrome and he had been treated with prednisolone. His symptoms rapidly improved and complete remission was achieved 38 days after the ATRA therapy. This was the first report of patients in Japan considered to have developed "retinoic acid syndrome (RAS)". In our five APL cases treated with ATRA, the syndrome was not always accompanied by peripheral blood leukocytosis even though the two cases with RAS showed higher leukocyte counts than the other two cases without RAS and also had DIC. We should pay attention to the severe respiratory symptoms that develop in APL patients after ATRA treatment and immediate steroid therapy is required for such patients.

Adult↗
PubMed1993

Multi-institutional study of all-trans-retinoic acid as a differentiation therapy of refractory acute promyelocytic leukemia. Leukaemia Study Group of the Ministry of Health and Welfare.

We treated 70 acute promyelocytic leukemia (APL) patients with daily oral 45 mg/m2 all-trans-retinoic acid (ATRA) in two multi-institutional prospective studies. Of 64 evaluable patients, 21 were refractory to initial induction chemotherapy; 10 were refractory to salvage chemotherapy; 17, five, and four were in the first, second and, third relapse, respectively; and seven were previously untreated due to old age. In the first study with ATRA from China, 18 out of 22 (82%) evaluable patients achieved complete remission (CR). Initial peripheral leukemia cell counts were significantly less in the CR cases (p < 0.01); < 100/microliters in 17 out of 18 CR cases, and > or = 200/microliters in all failure cases. In the second study with ATRA from Hoffmann-La Roche, if initial leukemia cell counts were more than 200/microliters, chemotherapy was first given and then ATRA was started. Of 42 evaluable patients, 36 (86%) achieved CR. Morphological evidence of differentiation was noted in all CR cases. Patients achieving CR received standard consolidation and maintenance chemotherapies, and the 20-month predicted disease-free survival rate is 76% for cases achieving their first CR with ATRA. Toxicities attributable to ATRA were minimal and included cheilitis, xerosis, dermatitis, gastrointestinal disorders, bone pain, liver damage, and high serum triglyceridemia.

Adolescent↗
PubMed1993

[State of the art of chemotherapy for adult acute leukemia in Japan].

For a disease like leukemia with an annual incidence of 3 to 4 per a 100,000 population, a multicenter cooperative study is essential to develop better therapeutic regimens. Our Japan Adult Leukemia Study Group (JALSG) started its first multicenter cooperative study in 1987. In the AML 87 study, response-oriented individualized induction therapy produced 78% complete remissions in 252 consecutive adult AML, a higher remission rate than that of any multicenter studies in the U.S.A. and Europe. For further development of clinical study for cancer in Japan, financial support to highly qualified clinical study groups by the government is urgently needed.

Acute Disease↗
PubMed1993

[Clinical Oncology Groups in Japan: experience of the Japan Adult Leukemia Study Group (JALSG)].

Although Grants-in-Aid of the Ministry of Health and Welfare support a considerable number of clinical cancer studies in Japan, there is no established clinical oncology group in Japan which is supported by the government or public grants. The Japan Adult Leukemia Study Group is a voluntary clinical oncology group, established in 1987; it started with 14 institutions and had 45 institutions as of 1993. Operating funds are donated from each participating institution with some help from a Grant-in-Aid of the Ministry of Health and Welfare of Japan. Establishment of government-supported nation-wide clinical oncology groups is urgently needed for further development of high quality clinical cancer studies in Japan.

Acute Disease↗
PubMed1993

[Differentiation therapy of acute promyelocytic leukemia with all-trans retinoic acid].

We treated 70 patients with acute promyelocytic leukemia (APL) with daily oral 45 mg/m2 all-trans retinoic acid (ATRA) in 2 multi-institutional prospective studies. Of 63 evaluable patients, 21 were resistant to initial induction chemotherapy, 10 were resistant to salvage chemotherapy after relapse, 17 were in the first relapse, 4 in the second relapse, 4 in the third relapse, and 7 were previously untreated. In the first study with ATRA from China, 18 (82%) of 22 evaluable patients achieved CR within 8 to 53 days with a median of 29 days. Initial peripheral leukemia cell counts were significantly less in the CR cases (p < 0.01). They were less than 100/mm3 in 17 of 18 CR cases, and more than 200/mm3 in all failure cases. Patients achieving CR received standard consolidation and maintenance chemotherapies, and the 16-month predicted continuing CR rate is 60%. Based on the first study, in the second study with ATRA from Hoffmann-La Roche AG, if initial peripheral leukemia cell counts were more than 200/mm3, chemotherapy was first given and then ATRA was started. Of 41 evaluable patients, 36 (88%) achieved CR within 11 to 91 days with a median of 34 days. Of 3 patients who received preceding chemotherapy due to high leukemia cell counts, 2 achieved CR. Morphological evidence of differentiation was noted in all CR cases, with Auer rods in mature segmented neutrophils in 13 cases. The clinical signs of DIC decreased rapidly within a few days and disappeared in CR cases. Toxicities attributable to ATRA were minimal and included cheilitis, xerosis, dermatitis, gastrointestinal disorders, bone pain, liver damage and high serum triglyceridemia.

Administration, Oral↗
PubMed1993

Unexpected heterogeneity of PML/RAR alpha fused mRNA detected by nested polymerase chain reaction in acute promyelocytic leukemia.

We have analyzed ten APL patients using reverse transcription polymerase chain reaction (RT-PCR) technique to detect PML/RAR alpha fused mRNA. All patients in this study had PML/RAR alpha fused mRNA (three cases of the short type and seven cases of the long type), although the chromosomal translocation t(15;17) was not detected in one patient. After ethidium bromide staining, two-thirds of the short type and all cases of the long type were found to have multiple PCR products (192 and 93 base pair (bp) bands in the short type and 666, 522, 263, and 164 bp in the long type). A total of six distinct fused mRNAs were sequenced (P1R1, P1R2, P3R1, P2R1, and P2R2). Southern hybridization analysis showed only one rearranged band in each of the patients. These results suggest that the longest mRNAs in each type are the authentic fused mRNAs and the other smaller mRNAs are generated through splicing events. In RAR alpha, a novel fusion point (R2) was identified within the fourth exon. This uncommon splicing may be caused by the instability of the splicing mechanism of the rearranged PML/RAR alpha gene. Among the ten APL patients, no correlation was observed between the type of fused mRNA and the clinical characteristics examined.

Adult↗
PubMed1993

[Differentiation therapy of acute promyelocytic leukemia with all-trans retinoic acid].

We treated 70 patients with acute promyelocytic leukemia (APL) with daily oral 45 mg/m2 all-trans retinoic acid (ATRA) in 2 multi-institutional prospective studies. Of 63 evaluable patients, 21 were resistant to initial induction chemotherapy, 10 were resistant to salvage chemotherapy after relapse, 17 were in the first relapse, 4 in the second relapse, 4 in the third relapse, and 7 were previously untreated. In the first study with ATRA from China, 18 (82%) of 22 evaluable patients achieved CR within 8 to 53 days with a median of 29 days. Initial peripheral leukemia cell counts were significantly less in the CR cases (p < 0.01). They were less than 100/cmm in 17 of 18 CR cases, and more than 200/cmm in all failure cases. Patients achieving CR received standard consolidation and maintenance chemotherapies, and the 16-month predicted continuing CR rate is 60%. Based on the first study, in the second study with ATRA from Hoffmann-La Roche AG, if initial peripheral leukemia cell counts were more than 200/cmm, chemotherapy was first given and then ATRA was started. Of 41 evaluable patients, 36 (88%) achieved CR within 11 to 91 days with a median of 34 days. Of 3 patients who received preceding chemotherapy due to high leukemia cell counts, 2 achieved CR. Morphological evidence of differentiation was noted in all CR cases, with Auer rods in mature segmented neutrophils in 13 cases. The clinical signs of DIC decreased rapidly within a few days and disappeared in CR cases. Toxicities attributable to ATRA were minimal and included cheilitis, xerosis, dermatitis, gastrointestinal disorders, bone pain, liver damage and high serum triglyceridemia.

Administration, Oral↗
PubMed1992

The effect of amino acid substitution at position 219 of Citrobacter freundii cephalosporinase on extension of its substrate spectrum.

The cephalosporinase of Citrobacter freundii GN346 is a class-C beta-lactamase comprising 361 amino acids. The substitution of the glutamic acid at position 219 in the enzyme by lysine was previously shown to broaden its substrate specificity to unfavorable substrates such as oxyimino cephalosporins [Tsukamoto, K., Ohno, R. & Sawai, T. (1990) J. Bacteriol. 172, 4348-4351]. To investigate the cause of this phenomenon, Glu219 was changed to glutamine, cysteine or tryptophan. All the resultant enzymes showed higher cefuroxime-hydrolytic activities than the wild type, the order of increasing cefuroxime-hydrolytic activity being as follows: Trp greater than Lys greater than Cys greater than Gln greater than Glu. The rate of hydrolysis of cefuroxime by the Trp219 enzyme was approximately 3 x 10(4) times that of the wild-type enzyme. The order of increasing cefuroxime hydrolysis was approximately proportional to the molecular volume of the amino acid substituted and independent of the ionic character of the amino acids. The cysteine residue at position 219 in the Cys219 enzyme allowed its complete reaction with an SH-blocking reagent, 4-chloromercuriphenylsulfonic acid. The modified enzyme with the bulkier residue showed a 45% higher cefuroxime-hydrolytic activity than the untreated enzyme. These results suggested that extension of the substrate spectrum may be attributed to alteration in the configuration of the enzyme around position 219.

Amino Acids↗
PubMed1992

Phase II study: treatment of non-Hodgkin's lymphoma with an oral antitumor derivative of bis(2,6-dioxopiperazine).

BACKGROUND: Although razoxane (ICRF-159), a derivative of bis(2,6-dioxopiperazine), has shown significant antitumor activity in several murine tumors, inadequate bioavailability has limited its clinical efficacy. Sobuzoxane (MST-16), another derivative of bis(2,6-dioxopiperazine), has shown activity against a broad spectrum of murine tumors and human tumor xenografts in nude mice and a lack of cross-resistance to vincristine, doxorubicin, cyclophosphamide, fluorouracil, etoposide, and mitomycin C. These findings suggest that MST-16 has a mode of cytocidal activity different from that of other antitumor agents. PURPOSE: The present late phase II study was conducted to evaluate the clinical efficacy and toxicity of MST-16 in non-Hodgkin's lymphoma (NHL). METHODS: As part of a multi-institutional cooperative study, we conducted a study of MST-16 in 27 patients with NHL who were assessable for drug efficacy and toxicity. MST-16, a bis(2,6-dioxopiperazine) analogue and an inhibitor of topoisomerase II, was administered orally at a dose of 1600 mg/m2 a day for 5-7 days at intervals of 2-3 weeks. RESULTS: Response consisted of one complete remission and seven partial remissions in 27 assessable patients. Response was achieved at a median of 13 days (range, 9-62 days) after initiation of therapy and lasted a median of 46 days (range, 29-155 days). Major toxic effects were leukopenia in 70% of the patients, thrombocytopenia in 44%, and gastrointestinal disorders in 37%. CONCLUSIONS: MST-16 was shown to be effective in NHL and deserves further clinical trial, since the drug shows little cross-resistance to available antitumor drugs. IMPLICATIONS: Phase II clinical studies of MST-16 in treatment of breast cancer, gastric cancer, and adult T-cell leukemia and lymphoma are also being conducted in Japan. Future trials of combination chemotherapy using MST-16 with other antitumor drugs are warranted in view of the additive effects observed in studies of MOLT-3 cells and studies of L1210 leukemia in mice.

Administration, Oral↗
PubMed1992

Antibody dependent cell mediated cytotoxicity on human cervical carcinoma cell line, ME-180, with human monoclonal antibody.

A human monoclonal antibody (MCA), CLN-IgG, showed cytotoxic effect in vitro against the cervical carcinoma cell line, ME-180, by antibody dependent cell-mediated cytotoxicity (ADCC). To determine which fractions of cells in peripheral blood lymphocyte (PBL) mediate ADCC, PBL were separated with nylon wool column and sheep red blood cells (SRBC). Both adherent cells (monocyte) and non-T, non-B cells showed cytotoxicity by ADCC. Human non-T, non-B cells showed higher cytotoxic activity against ME-180 cells than monocytes. Furthermore murine effector cells were less effective in ADCC than human effector cells with human MCA.

Antibodies, Monoclonal↗