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Biomedical subjects

S Misawa

Publications and source records attributed to S Misawa.

At least 325 records · Page 18Linked to original sources
PubMed1984

Unusual karyotypic changes and B cell involvement in a case of lymph node blast crisis of chronic myelogenous leukemia.

A patient with Philadelphia chromosome (Ph1) positive chronic myelogenous leukemia (CML) entered a blast crisis localized to lymph nodes. On light microscopy, by morphology and histochemical staining, the blasts were undifferentiated. In spite of terminal deoxynucleotidyl transferase positivity, some of the lymph node cells expressed a myeloid differentiation antigen, OKM1, and were peroxidase positive by transmission electron microscopy (TEM). However, the majority of cells were peroxidase negative on TEM and expressed OKT-10, a marker found on both primitive myeloid and lymphoid cells. Cultures of lymph node cells stimulated with Epstein-Barr virus or lipopolysaccharide (LPS) revealed the Ph1, indicating B cell involvement in the CML. T cells from cultures stimulated with L4-phytohemagglutinin and T cell growth factor were negative for the Ph1. In unstimulated lymph node cells, the uncomplicated Ph1 could not be demonstrated; instead, a unique complex karyotype involving a masked Ph1 was identified in these and the LPS cultures. This karyotype was not found in bone marrow (BM) metaphase cells. Instead, BM cells showed either the simple Ph1 or the Ph1 with a rearrangement involving chromosomes 13 and 20. The patient had transient responses to three chemotherapy regimens, two of which were designed to treat acute lymphocytic leukemia, but he died 8 months after disease acceleration without BM blast crisis. These findings are compatible with an extramedullary blast crisis originating in a primitive cell with both myeloid and lymphoid characteristics.

Adult↗
PubMed1984

The "loss" of centromeres from chromosomes of aged women.

Both aneuploid cells in mitosis and nondisjunction in meiosis increase with advancing age. The cause(s) of these phenomena remains unknown. Here, it was confirmed that a positive Cd-band reflects the presence of a functioning centromere while a negative reaction is indicative of its inactivation or loss. We applied the Cd-banding technique to mitotic spreads obtained from 14 aged and 13 control females (peripheral blood culture). Of 6,474 scored chromosomes from the aged women, 62(0.96%) were Cd-negative; this was the case in 12 of 3,861 (0.31%) chromosomes from the younger controls. The difference was highly significant (P less than .001). About 60% of the 62 Cd-negative chromosomes from aged women belong to the C group. Chromosomes from six of the 14 aged females were additionally examined by either the C-band or the distamycin-DAPI technique; of 2,080 chromosomes, 13 (0.63%) showed premature separation of their centromeres (control: 7/5, 080, 0.14%). Our findings suggest that in aged women, the chromosomes tend to lose their Cd-positive material and the function of the centromere.

Aged↗
PubMed1983

A variant 8;21 translocation in acute myeloblastic leukemia.

A three-way rearrangement involving chromosomes 1, 8, and 21 was observed in bone marrow cells from a female with acute myeloblastic leukemia, subtype M2 (AML-M2). The translocation break points in chromosomes 8 and 21 were identical to those found in the standard t(8;21) that is associated with this disease type. A review of this and four previously reported cases involving variant 8;21 translocations indicates that a consistent pattern of exchange may be involved in these complex rearrangements even though the third chromosome affected may differ.

Adult↗
PubMed1983

Cytogenetic evidence of clonal evolution in a case of hemopoietic dysplasia with a 5q- chromosome.

A 70-year-old Japanese male with hemopoietic dysplasia is described. Cytogenetic investigation revealed an abnormal karyotype, 46,XY,del(5)(q13q33), in all metaphases examined at the time of diagnosis. Eight months later, a newly appearing abnormal hyperdiploid karyotype, 47,XY,5q-, +21, was observed in 74% of the cells analyzed, which was associated with evolution of the disease when a pathologic diagnosis of a myeloproliferative disorder was made.

Aged↗
PubMed1981

Effects of amino acids, especially taurine and gamma-aminobutyric acid (GABA), on analgesia and calcium depletion induced by morphine in mice.

The analgesic effect of morphine was antagonized in mice by intracerebroventricular pretreatment with taurine, gamma-aminobutyric acid (GABA) or glycine and was potentiated by ethylene glycol tetra-acetic acid (EGTA) but not altered by L-glutamate or L-aspartate. The potentiation of morphine analgesia by EGTA was reversed by a concentration of taurine that did not alter the tail-flick response. The selective depletion of 45Ca2+ from synaptic vesicles observed with morphine administration was significantly inhibited by taurine injection (1.2 mumol/brain, i.vt.) but was not altered by the same dose of GABA. Inhibition of ATP-dependent 45Ca2+ uptake in synaptosomes by morphine was also completely reversed by taurine (10(-2)M which by itself did not alter 45Ca2+ uptake. These results suggest that antagonism of morphine analgesia by taurine may be caused by blockade of the morphine-induced inhibition of both ATP-dependent synaptosomal 45Ca2+ uptake and changes in synaptic vesicular 45Ca2+ localization, while the antagonism by GABA was not associated with synaptosomal Ca2+.

Amino Acids↗
PubMed1981

The HLA antigens of two Negrito populations in the Philippines.

HLA antigens were determined for the A, B and C loci among 86 Aetas of west-central Luzon and 87 Mamanwas of north-eastern Mindanao, Philippines. The overall antigenic profiles of these two groups were essentially similar to those of other Asian-Pacific populations with some peculiarities in common with Papua New Guineans. However, the results of heterogeneity tests and the comparison of statistically significant phenotypic associations showed a highly significant difference between the Aeta and the Mamanwa groups. It was postulated that the two "Negrito" groups represent different migrations to the Philippines.

Black People↗