Duplication of 1q in a child with down syndrome and myelodysplastic syndrome.

Cytogenetic analysis of bone marrow cells was performed on a 2-year-old African-American male with Down syndrome (DS) and myelodysplastic syndrome (MDS), specifically refractory anemia with excess blasts in transformation (RAEB-T). Chromosome analysis showed, in addition to the constitutional trisomy 21, a trisomy of chromosome 11 and a dup(1)(q23q31). This duplication of 1q is apparently a new chromosomal abnormality in a child with MDS.

Leukemia cutis: Darier's sign in a neonate with acute lymphoblastic leukemia.

Infantile leukemia accounts for only 3% of childhood leukemia. Leukemia cutis occurs in 25% to 30% of infants with congenital leukemia and is more frequently associated with acute myeloid leukemia than with acute lymphoblastic leukemia. We describe an infant in whom hyperpigmented macules that developed when the patient was 2 weeks old demonstrated Darier's sign when he was 4 weeks old.

Control of the growth of leukemic cells (L1210) through manipulation of trace metals.

Trace metals have a role in the activity of the enzyme ribonucleotide reductase (RR) which is essential for the synthesis of DNA and the growth of lymphocytes. Manipulation of the intracellular metals of leukemic cells has been proposed for the therapeutic control of cell growth. We studied the effects of prolonged metal deprivation (Fe, Cu, Zn) on cell growth and RR activity of murine leukemic lymphocytes in culture in metal-depleted media.

Growth, ribonucleotide reductase and metals in murine leukemic lymphocytes.

Trace metals are essential for the growth and several other properties of human lymphocytes. We studied the effects of media with variable concentrations of three metals (Fe2+, Cu2+, Zn2+), a metal chelator (deferoxamine, DFX) and a cell-growth inhibitor (hydroxyurea) on the growth, intracellular metal concentration and activity of the enzyme ribonucleotide reductase in murine leukemic lymphocytes (L1210). Intracellular concentrations of Fe and Cu fluctuated within narrow limits in normal media, but decreased to very low concentrations in metal-poor media.