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Biomedical subjects

J Mimaya

Publications and source records attributed to J Mimaya.

At least 55 records · Page 3Linked to original sources

Time-course detection of HIV-1 proviral DNA and genomic RNA by polymerase chain reaction in sera from seropositive and seronegative hemophiliacs treated with clotting factor concentrates.

The detection of HIV-1 proviral DNA and genomic RNA was performed by polymerase chain reaction (PCR) in hemophiliacs treated with non-heated clotting factor concentrates. Reamplification with double PCR was performed on those samples that were negative for single PCR. Primer pairs of the gag, env, and pol regions were used for the amplification of HIV-1 proviral DNA sequences. Amplification of the gag region by the SK38/SK39 primer pair was useful for the detection of proviral DNA sequences. With double PCR, 44 of 47 seropositive samples (93.6%) were PCR-positive. All 23 seronegative samples were PCR-negative. Reverse transcription and PCR amplification (RT-PCR) according to the primer pair of the gag region were performed to detect HIV-1 genomic RNA sequences. Double RT-PCR analysis of the HIV-1 RNA sequence in frozen-preserved sera revealed that 49 of 55 seropositive sera (89.1%) were PCR-positive. Although quantification of the PCR method was not performed in this study, we concluded that, in patients in whom proviral DNA or genomic RNA sequences are detected with difficulty with PCR, the onset and progression of HIV-1 infection is delayed.

Blood Coagulation Factors↗

[Detection of HIV-1 proviral DNA and RNA in serum from HIV-1 sero-positive hemophiliacs by polymerase chain reaction].

We amplified HIV-1 proviral DNA and RNA in serum by DNA-PCR and RT-RCR in 20 HIV-1 seropositive hemophiliacs asymptomatic carrier (AC): 10, AIDS-related complex (ARC):8, AIDS:2). HIV-1 DNA sequences were identified in 44 (93.6%) of 47 specimens. 23 (92.0%) of 25 samples in AC, 13 (100%) of 13 in ARC, 8 (88.8%) of 9 in AIDS had detectable bands. RNA sequences were identified in 36 (85.7%) of 42 specimens. 17 (70.8%) of 24 specimens in AC, 13 (100%) of 13 in ARC, 5 (100%) of 5 in AIDS cases had detectable bands. RNA in serum was strongly positive in two asymptomatic patients with progression to AIDS who showed no changes of other markers. Patients with almost normal CD4 cell counts had trace amounts of proviral DNA and RNA in serum. RNA in serum is the parameter most predictive of progression to AIDS and is detectable earlier than other parameters. From the results of RT-PCR before and after seroconversion, the serum of one patient was shown to be positive at 5 months before seroconversion.

Acquired Immunodeficiency Syndrome↗

[Analysis of cytoplasmic antigens in acute leukemia by flow cytometry].

The expression of cytoplasmic antigens in 77 cases of acute leukemia were analyzed by flow cytometry using the following monoclonal antibodies: CD3, CD22, anti-myeloperoxidase (MPO-7) and anti-mu-heavy chain. CD22 antigen was detected in the cytoplasm of all non-T-ALL patients excluding one not-tested patient. In two patients with unclassified ALL, surface CD22 antigen was not expressed but cytoplasmic CD22 antigen was strongly expressed. Three out of 9 patients with common ALL were cytoplasmic mu-heavy chain-positive, so these patients were diagnosed as Pre-B ALL. In four out of 8 patients with T-ALL, CD3 antigen was not expressed on the cell surface membrane. However all of T-ALL patients excluding one non-tested patient were cytoplasmic CD3-positive. The cytoplasmic expression of myeloperoxidase antigen was detected in twenty out of 21 patients with acute non-lymphoblastic leukemia (ANLL). One megakaryocytic leukemia patient was MPO-negative. In two ANLL patients, the percentage of MPO for conventional cytochemical staining was undetectable or low, but MPO antigens were positive (77% and 70%) for flow cytometric analysis. All of 46 non-T ALL patients were cytoplasmic MPO-negative, however 4 out of 10 T-ALL patients were cytoplasmic MPO-positive. The study proved that the analysis of cytoplasmic CD3, CD22, mu-chain and MPO antigens were very useful to define the cell lineage of leukemia and to classify ALL and ANLL. It is necessary to study further whether the expression of MPO in the cytoplasm of T-ALL was non-specific reaction or whether MPO precursors are expressed in the cytoplasm of T-ALL.

Adolescent↗

[CD5+, CD7+, and CD19+ non-Hodgkin's lymphoma in a child].

The 9-year-old boy was admitted to Shizuoka Children's Hospital because of cervical lymphoadenopathy. Complete blood count showed normal RBC and platelet counts. WBC was 2700/microliters with no tumor cells. Bone marrow aspirate showed normocellularity with 34% tumor cells. Lymph node biopsy from his right neck was performed and the patient was diagnosed as non-Hodgkin's lymphoma (lymphoblastic type). Surface marker analysis disclosed that the tumor cells were positive for CD5, CD7, CD19, CD38, CD71, and Ia antigen. Chromosomal analysis of the cervical lymph node revealed 46, XY, t(7;14) (p15;q32). Molecular investigation with appropriate probe showed germ-line configurations of IgH gene, TcR beta gene, and TcR gamma gene, and one rearranged band of TcR delta gene. Monoclonality of tumor cells was demonstrated from chromosomal analysis and molecular study. CD7 and CD19 are not lineage specific antigens because CD7 is expressed on immature AML cells and CD19 is expressed on T ALL cells or AML cells. Moreover, TcR delta rearrangement is considered to occur at early phase of hematolymphoid cells. Based on these data, tumor cells of this patient is considered to originate from immature lymphoid cell, so-called lymphoid stem cell.

Antigens, CD19↗

Retrospective analysis of late intensification therapy with high-dose methotrexate for standard-risk acute lymphoblastic leukemia in childhood (CCLSG-S811 study). The Children's Cancer and Leukemia Study Group.

Using the CCLSG-S811 protocol for children with standard-risk acute lymphoblastic leukemia (ALL), late intensification therapy (LIT) with high-dose methotrexate (HD-MTX) was conducted without randomization. Of 118 eligible patients, 114 attained complete remission and 82 maintained continuous complete remission (CCR) for at least 3 years, completing the entire S811 regimen. Among the latter, 74 patients received LIT with HD-MTX between 2-3 years after CCR onset. MTX (2,000 mg/m2 per dose per week) was administered by 24 h infusion and three doses were given every 12 weeks. Leucovorin rescue (15 mg/m2 i.v.) every 6 h was initiated 12 h after the end of MTX infusion for seven doses. As regular maintenance chemotherapy, intermittent (Regimen A) or continuous (Regimen B) MTX plus 6-mercaptopurine (6MP) combined with pulses of prednisolone and vincristine was administered (Koizumi S, Fujimoto T, Takeda T, et al. Cancer 1988; 61: 1292-1300). Retrospective analysis revealed that patients on Regimen A who started LIT earlier (within 2 years of CCR onset (n = 23)) showed a higher rate of event-free survival (EFS) at 8 years (95.5% +/- 4.4%, mean +/- S.E.) than patients who started LIT later (2.5 years after CCR onset (n = 18, 66.2% +/- 11.3%, p less than 0.01)). In addition, the superiority of four or five courses of the LIT (n = 39) as compared to 2 or 3 courses (n = 35) was noted for both regimens. The data suggest that early and aggressive LIT with HD-MTX may improve the long-term survival of childhood ALL patients.

Antineoplastic Combined Chemotherapy Protocols↗

Successful treatment of acute leukemia with t(4;11) in an infant with congenital hypothyroidism.

We describe a case of acute leukemia with t(4;11) (q21;q23) in a 3-month-old girl suffering from congenital hypothyroidism. The blast cells were cytochemically and immunologically classifiable as acute lymphoblastic leukemia of an early B-cell lineage (HLA-DR +, B4 +, CALLA-). but we treated this patient with a protocol designed mainly for acute nonlymphocytic leukemia, employing Adriamycin, vincristine, and cytosine arabinoside. Although the prognosis of this type of leukemia is known to be extremely poor, our patient is currently alive and in continuous complete remission lasting 35 months to date. This case may demonstrate a potential alternative therapeutic strategy for acute leukemia with t(4;11) as well as clinical evidence for the mixed-lineage characteristics of this condition. However, the pathogenetic role of congenital hypothyroidism in the development of acute leukemia is still uncertain.

Antineoplastic Combined Chemotherapy Protocols↗

[Hemopoietic factor producing hepatocellular carcinoma in a child].

A 12-year-old boy with hepatocellular carcinoma presented with marked neutrophilia up to 69,200/microliters and elevation of serum colony stimulating activity (CSA) and burst promoting activity (BPA). After resection of the tumor, neutrophil count returned to the normal value and hemopoietic activities in serum decreased. However, on relapse, both elevated to the preoperative levels. Hemopoietic activities in the medium conditioned with tumor tissue were investigated using normal human bone marrow as the target cells, and both CSA and BPA were demonstrated. From these findings, it could be considered that the tumor tissue produced a substance that stimulated both myelopoiesis and erythropoiesis.

Carcinoma, Hepatocellular↗

Identification of myeloid origin in undifferentiated congenital leukemia by in vitro marrow culture study.

A case of congenital leukemia that originally did not express any lineage-specific antigenic markers is presented. The blast cell morphologic appearance was L1 according to French-American-British (FAB) classification and showed lymphoid characteristics by cytochemical staining and transmission electron microscopy. However, immunophenotyping using a variety of monoclonal antibodies did not confirm the lymphoid origin. Furthermore, the immunoglobulin heavy chain and T-cell receptor beta-chain genes were in germ-line configuration. The in vitro culture study defined the leukemia as of myeloid origin. The semisolid methylcellulose culture showed an acute non-lymphocytic leukemia-type growth pattern. Bone marrow blasts underwent myeloid differentiation with positive myeloperoxidase and butyrate esterase activity during a suspension culture. These findings indicate that this case represents an acute undifferentiated leukemia that has probably arisen from the malignant transformation of stem cells of myeloid progeny.

Antineoplastic Combined Chemotherapy Protocols↗

Comparison of intermittent or continuous methotrexate plus 6-mercaptopurine in regimens for standard-risk acute lymphoblastic leukemia in childhood (JCCLSG-S811). The Japanese Children's Cancer and Leukemia Study Group.

From 1981 to 1983, 131 previously untreated patients with acute lymphoblastic leukemia (ALL) standard-risk group were entered to the protocol JCCLSG-S811. Of 119 eligible patients, 115 (96.6%) attained complete remission by treatment with prednisone (PRD) plus vincristine (VCR) or vindesine (VDS). After preventive central nervous system (CNS) therapy including 18 Gy cranial irradiation and three doses of intrathecal methotrexate (MTX), the patients were assigned randomly to the two maintenance chemotherapies, Regimen A and Regimen B. Regimen A (intermittent regimen) consisted of PRD (120 mg/m2/day by mouth for 5 days) plus 6-mercaptopurine (6MP) (175 mg/m2/day by mouth for 5 days) plus VCR (2.0 mg/m2 intravenously) alternating biweekly with MTX (225 mg/m2 intravenously). Regimen B (continuous regimen) consisted of 6MP (50 mg/m2/day by mouth) plus MTX (20 mg/m2/week by mouth) combined with pulses of PRD and VCR (the same dosages as Regimen A) every 4 weeks. As the late intensification therapy (LIT), five courses of high-dose MTX (2000 mg/m2 per dose per week intravenously for three doses every 12 weeks) with leucovorin rescue were administered to all patients who were in continuous complete remission (CCR) for more than 2 years. Sixty and 55 patients, respectively, were registered in Regimen A and B. The CCR rates in Regimen A and B were 75.1% +/- 5.8% (mean +/- 1 SE) and 49.7% +/- 7.3% (P less than 0.01) at 4 years, and 72.1% +/- 6.3% and 49.7% +/- 7.3% (P less than 0.05) at 5 years, respectively. In Regimen B, CNS and testicular relapses increased after 3 years of CCR. In addition, the patients in Regimen B had a much higher incidence of infections than Regimen A. The LIT did not seem to have important effects on the duration of CCR. From these data we conclude that the intermittent cyclic regimen of 6MP and MTX may be more effective as compared to the continuous administration of these drugs in the maintenance chemotherapy.

Antineoplastic Combined Chemotherapy Protocols↗

Clinical characteristics of infant acute leukemia with or without 11q23 translocations.

Of 34 infants less than 1 year of age with acute leukemia, 20 had an 11q23 translocation (group I), 8 had t(4;11), 5 had t(11;19), 3 had t(1;11), 2 had t(10;11), 1 had t(9;11), and the other had an 11q+ chromosome. Nine had other chromosome changes (group II), including t(1;19), t(8;14), 5q- chromosome, or +8 in one each, and a translocation involving 7p22 in two. The other five had normal diploidy in their leukemic cells (group III). Thus, the 11q23 translocation was seen in 50% of the leukemic infants, and in as high as 75% of the infants less than 6 months old. While the 7p22 translocations were both seen in those less than 6 months, the four chromosome abnormalities without 11q23 translocation mentioned above and normal diploidy were found only in those 6 months old or more. The group I patients had higher leukocyte counts than the group II (p less than 0.05) or group III (p less than 0.01) patients. Of the 20 group I patients, 16 were classified as having ALL, and 4 were classified as having ANLL. Eleven of 15 ALLs with the 11q23 translocation showed an Ia+, CALLA-, and B4+ (8 of 9 examined) immunophenotype. Coexpression of lymphoid and myeloid Ags was seen in four ALLs and two ANLLs with the 11q23 translocation. The survival of group II patients (median, 9 months) was significantly shorter than that of group I (median, 19 months) (p less than 0.05) or group III (median, 44 months) (p less than 0.01) patients; the difference in the survival between group I and group III patients was not significant. It is noteworthy that 5 of the 20 group I patients have survived 20 months or more without relapsing.

Antigens, Differentiation↗

Erythropoiesis during an erythroblastic phase of chronic myeloproliferative disorder associated with monosomy 7.

A chronic myeloproliferative disorder associated with monosomy 7 is described in a 3 1/2-year-old boy. His presenting features closely resembled those of juvenile chronic myeloid leukaemia (JCML). Cytogenetic study of bone marrow cells showed that all of the metaphases examined had chromosome 7 deletions. He developed an erythroblastic phase, characterized by anaemia, marked erythroid hyperplasia of bone marrow and the appearance of nucleated red blood cells in the peripheral blood. During the erythroblastic phase, blood transfusion resulted in a suppression of erythropoiesis as evidenced in both the peripheral blood and bone marrow. The in vitro culture studies showed that the erythroid precursor was dependent upon erythropoietin (Ep) for differentiation and proliferation during the erythroblastic phase. However, the Ep dose-response curve showed that a peak of erythroid colony formation occurred at a lower concentration than in the healthy controls. These findings suggest that although the erythroid precursor remains under the control of Ep, it has an increased sensitivity to Ep during the erythroblastic phase of monosomy 7.

Blast Crisis↗