Differential action of diffusible molecules in long-term marrow culture on proliferation of leukaemic and normal haemopoietic cells

The capacity of diffusible molecules in the fluid phase of long-term human bone marrow culture (LTMC) to exert preferential adverse effects on leukaemic relative to normal haemopoietic cells has been investigated. Responses of isolated cell populations were assessed in diffusion chamber inserts which permitted contact with fluid phase molecules but not with the adherent stromal cell layer of the LTMC system. Growth of AML cells in diffusion chambers was inhibited during co-culture with LTMC of autologous leukaemic bone marrow, and the same effect was produced during co-culture with normal LTMC. No inhibitory action was exerted on growth of normal haemopoietic precursors under the same conditions. Comparable responses were observed with human leukaemic cell lines and patient leukaemic cells, and studies on cell lines demonstrated inhibition of growth was induced by molecules generated in LTMC which caused accumulation in G1 phase of leukaemic cells of both myeloid and lymphoid lineage. The inhibitory effect was not reproduced by TGF beta, IFN gamma, IFN alpha, TNF alpha, LIF, SCF or Il-6, and was not impaired by inhibitors of nitric oxide or PGE production in the LTMC. These observations suggest the action of diffusible molecules of undefined constitution contributes to the preferential loss of leukaemic cells in LTMC.

Novel translocation (2;4) with consistent involvement of 2p23 in acute nonlymphocytic leukemia (M2)

A translocation involving the short arm of chromosome 2 and the long arm of chromosome 4 is described in three patients, all of whom had acute nonlymphocytic leukemia (M2). One patient had M2 de novo, one progressed from refractory anemia with excess blasts in transformation to M2 over a 4-month period, and one had had sideroblastic anemia 30 years prior to development of M2. In all three patients, the translocation involved the breakpoint p23 on chromosome 2, but the breakpoints on chromosome 4 varied between q25, q31, and q35. Translocations specifically involving 2p23 have not previously been described in leukemia, but more cases are required to identify a specific association with either the FAB type or prognosis.

Effect of gamma irradiation and water activity on mycotoxin production of Alternaria in tomato paste and juice

Gamma-irradiation, water activity (aw) and incubation temperature were found to affect the production of tenuazonic acid (TZA) by Alternaria alternata in tomato paste and juice. By increasing the irradiation doses, the dry weight as well as TZA decreased greatly until complete inhibition at 4 kGy. Greatest production of TZA occurred at 0.98 aw (57.5 micrograms/g and 26.3 micrograms/g) for both tomato paste and juice, respectively, at 25 degrees C. Changing temperature and aw altered the relative amounts of TZA produced in tomato paste und juice by unirradiated and irradiated conidia of A. alternata. Only trace amount of TZA was detected at 0.98 aw (1.50 micrograms/g) by 3 kGy-irradiated conidia in tomato paste, while it was inhibited completely in juice. Increasing gamma-irradiation doses and decreasing water activities decreased greatly or inhibited TZA production in both tomato paste and juice.

Ethanolaminuria: a non-specific laboratory finding in the seriously ill infant

Ethanolamine is a compound that is frequently seen in urinary amino acid analysis. Although there is a single report of increased ethanolamine excretion associated with a distinctive storage disease in two siblings, the significance of ethanolaminuria is not known. We measured urinary ethanolamine/creatinine ratios in 102 hospitalized infants under two years of age and examined the clinical correlations in six cases whose ratios were more than five-fold higher than the maximum value for the established reference range. We found that ethanolamine excretion was strongly dependent on age even when the data were corrected for significant positive skewing. Increased ethanolamine excretion was common in the first week of life, but five of the six cases we specifically studied were characterized by progressive, debilitating illness and three of the six patients subsequently died. Although we found no evidence of a storage disorder, we did note that there was evidence of neuronal white matter degeneration in most but not all cases. Thus, ethanolaminuria appears to be a non-specific sign of severe neurological disease rather than a distinctive feature of a specific inborn error of metabolism.

Multiple general anaesthesia with Althesin

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Metastases of glioblastoma multiforme to cervical lymph nodes. Report of two cases

✓ Two cases of occipital glioblastoma multiforme are reported in which a metastatic lesion involving the cervical lymph nodes on the side of the previous craniotomy was verified during life. This suggests to the authors that the brain tumor metastasized via lymphatic channels.