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T Amenomori

Publications and source records attributed to T Amenomori.

32 records · Page 2Linked to original sources
PubMed1986

Cytogenetic evidence for partially committed myeloid progenitor cell origin of chronic myelomonocytic leukaemia and juvenile chronic myeloid leukaemia: both granulocyte-macrophage precursors and erythroid precursors carry identical marker chromosome.

We used a micromethod for cytogenetic analysis from single haematopoietic colonies to study two adults with chronic myelomonocytic leukaemia (CMML) and a boy with juvenile chronic myeloid leukaemia (JCML) carrying distinct chromosome abnormalities, 7q-, der(21), and trisomy 21. We wanted to know if both granulocyte-macrophage (GM) and erythroid precursors are involved in the abnormal clone. In all three patients, their chromosome abnormality was seen in almost all metaphases obtained from GM-colonies and erythroid bursts. Peripheral blood leucocytes stimulated with phytohaemagglutinin exhibited only normal karyotypes. Clones of B-cell produced by Epstein-Barr virus had only normal karyotypes in the CMML patients. These findings indicate that CMML and JCML are clonal haemopathies that originate in a partially committed myeloid progenitor cell.

Aged↗
PubMed1985

A micromethod for chromosome preparation from individual hematopoietic colonies cultured in methylcellulose.

We report a micromethod for chromosome preparation from individual hematopoietic colonies cultured in methylcellulose. The entire process was carried out on poly-Lysine (PL)-coated slides. Individual colonies were transferred into 10 microliter of 0.075 M KCl and placed on PL-coated slides. After hypotonic treatment of the colony cells and their attachment to the slides, the cells were fixed by a three-step procedure as follows: addition of a 30% fixative (3:1 methanol:acetic acid) diluted with the hypotonic solution, addition of 20% ethanol, and subsequent immersion of the slides in a 100% fixative. The slides were flame dried and Giemsa stained. Q- and G-banding techniques also were used. These procedures provided analyzable chromosome preparations, even from colonies containing fewer than 50 cells.

Aged↗
PubMed1985

CFU-C abnormalities and cytochemical defects in bone marrow of adult patients during remission of acute leukemia.

Twenty-three adult patients in complete remission (CR) from acute leukemia were investigated for the steady-state bone marrow (BM) CFU-C concentration and the cytochemical findings of neutrophils and monocytes. There was considerable variation in CFU-C concentrations among patients. Patients with abnormality high or low values tended to relapse earlier. Repeated assays revealed constant CFU-C values in individual long-term cases of remission (4 cases). One case of M4 (myelomonocytic) and the case of M5b (monocytic) leukemia revealed a complete lack of nonspecific esterase activity in CR monocytes as well as initial leukemic promonocytes; they also showed abnormally high or low concentrations of CFU-C and relapsed early. This finding suggests that hematopoiesis in CR bone marrow occurs from abnormal stem cells common to initial, acute leukemic clones in such cases.

Acute Disease↗
PubMed1985

A comparative study of immunological and cytochemical profiles between adult and childhood acute lymphoblastic leukemias (ALLs): heterogeneity in adult common ALL.

To investigate the biological differences between adult and childhood acute lymphoblastic leukemia (ALL), leukemic blasts from 33 patients with ALL (22 adults and 11 children) and from 11 patients in the lymphoid crisis of chronic myeloid leukemia (CML) were studied using cytochemical and immunological markers and also by the outcome of their treatment. The cytochemical studies showed that blasts from seven of the adult ALL patients were dense-granular-positive (DG-positive) for beta-glucuronidase, whereas the blasts from the children were negative except for one (with T-ALL). In the adults with common ALL (cALL), survival of patients DG-positive for this enzyme were significantly shorter than that of eight patients with a scattered granular pattern (p less than 0.05). The mean ratio between the percentage of blasts positive for cALL antigen (cALLA) to that of blasts positive for terminal deoxynucleotidyl transferase (TdT) in the adult group with cALL (0.6 +/- 0.3) was significantly lower (p less than 0.01) than in the group of children with cALL (1.1 +/- 0.2) or in the lymphoid-crisis group (1.5 +/- 1.0). These findings indicate that adult cALL consists of two distinct subpopulations, one with less differentiated phenotype (cALL-/TdT+) and the other with more (cALL+/TdT+). In contrast, the blast cells in childhood cALL and some patients in lymphoid crisis had a relatively homogeneous population with the latter phenotypes. The results suggest that the clonotypic cells in adult ALL, particularly in cALL, appear to be more immature than those in childhood ALL. The beta-glucuronidase patterns indicate a further heterogeneity in adult ALL.

Adolescent↗
PubMed1985

Lymphoid crisis with T-cell phenotypes in a patient with Philadelphia chromosome negative chronic myeloid leukaemia.

A case of Philadelphia (Ph1) chromosome negative chronic myeloid leukaemia (CML) developed lymphoid crisis. Immunological marker studies disclosed that the lymphoid cells were sheep erythrocyte-rosetting-, Leu-1+, Leu-5+, OKT-4+, OKT-8+, common ALL antigen-, HLA-DR-, cytoplasmic and surface immunoglobulin-, MAS 036C(antithymocyte)+ (after in vitro culture) and terminal deoxynucleotidyl transferase-, indicating T-cell phenotypes, probably of common thymocytes. Cytochemical staining also demonstrated immature T-cell characters: dot-positivity for acid phosphatase and beta-glucuronidase, and negative for acid alpha-naphthyl acetate esterase. All bone marrow metaphases exhibited normal karyotypes. Our observation suggests that the neoplastic features of a common stem cell for myeloid and lymphoid cell lines are very similar in Ph1 positive and negative CMLs, and that the stem cell can differentiate towards T-lineage.

Adult↗
PubMed1985

Low-dose cytosine arabinoside regimen induced a complete remission with normal karyotypes in a case with hypoplastic acute myeloid leukaemia with No. 8-trisomy: in vitro and in vivo evidence for normal haematopoietic recovery.

Complete remission was achieved in a case of hypoplastic acute myeloid leukaemia with chromosomal aberration of No. 8-trisomy by giving very low dose of cytosine arabinoside (ara-C), 10 mg (7 X 5 mg/m2)/d, by 24 h continuous intravenous infusion for 20 d. We observed a definite cytoreduction phase in the bone marrow (BM) before normal haematopoiesis resumed. The remission BM showed only normal karyotypes in all metaphases examined. Granulocyte/macrophage colonies and erythroid bursts recovered sufficiently in numbers and cytogenetic study on single colonies and bursts revealed only normal karyotypes. These observations provide evidence that a low dose ara-C regimen can induce remission by cytoreduction which diverts the growth advantage from the leukaemic clone to the normal clones.

Chromosomes, Human, 6-12 and X↗
PubMed1985

Cytochemistry of acute promyelocytic leukemia (M3): leukemic promyelocytes exhibit heterogeneous patterns in cellular differentiation.

Cytochemical investigation of leukemic promyelocytes from 25 cases of acute promyelocytic leukemia (M3) disclosed two major cellular differentiation categories: (1) the pure neutrophilic (N) type (16 cases) with strong myeloperoxidase (MPO) and naphthol-ASD chloroacetate esterase (Es-chl), but lacking the monocytic enzyme NaF-sensitive alpha-naphthyl butyrate esterase (Es-b), and (2) the mixed neutrophilic/monocytoid (N/M) type (seven cases) with strong Es-b as well as strong MPO, all cases exhibiting Es-dual (Es-b + Es-chl) positive cells. Two more cases with unusual phenotypes were noted: one with intense lysozyme activity but without Es-b and the other with toluidine blue-methachromasia and negative MPO. Promyelocytes from the control group, consisting of nine cases of t(8;21) M2 AML and ten cases with normal bone marrow, lacked such cytochemical heterogeneity. HL-60, an M3 cell line that can be induced to differentiate toward monocytic lineage in vitro, was almost negative for Es-b in the uninduced condition. Cytogenetically, eight cases of N type and five of N/M type had the t(15;17) abnormality. Thus at least two differentiation patterns were observed in M3 leukemia with fidelity (N type) and infidelity (N/M type) for normal granulocytic differentiation. In this series, there was no statistically significant difference in clinical features (remission rate and survival) between the two types. Our study suggests that the development of M3 leukemia is not exclusively restricted to the neutrophilic pathway, but more heterogeneously related to myelomonocytic differentiation.

Adolescent↗
PubMed1984

Reduced helper (OKT4+): suppressor (OKT8+) T ratios in aplastic anaemia: relation to immunosuppressive therapy.

T cell subset composition of peripheral blood and bone marrow from 22 patients with aplastic anaemia (AA) was studied by monoclonal antibodies (OKT3, OKT4 and OKT8). In the peripheral blood, OKT3 (pan-T), OKT4 (helper/inducer-T) and OKT8 (suppressor-T) cells varied widely in number. The ratios of OKT4:OKT8 exhibited the same tendency. However, a subgroup of AA with a reduced ratio of lower than 1.0 was present both in cases with or without prior prednisolone therapy. Of the eight patients treated with immunosuppressants, four with reduced ratios responded, whereas the other four with normal or higher ratios did not. The ratios of two of four responders gradually reached the normal level. These results suggest that the reduced OKT4:OKT8 ratio may be related to the cell-mediated immunosuppressive mechanism postulated as a cause of stem cell inhibition in a subgroup of AA, and indicate prospectively the effectiveness of immunosuppressive therapy.

Adolescent↗