Analysis of the erythrocyte membrane protein of an atypical case of congenital dyserythropoietic anaemia type II (CDA II) by electrophoresis on polyacrylamide gels revealed marked abnormalities. One-dimensional analysis showed a pronounced decrease in levels of B1.1 components, an increase in the level of B1.4 and the appearance of new components in the A region as well as in the C region of the gel. There were no artefacts due either to the presence of early red cells or to abnormally high levels of proteolytic enzyme activity in the CDA II preparations. Two-dimensional analysis confirmed the alterations in membrane components showing two novel A region species not reported in other studies of this disease. Abnormalities in components of such large molecular size may explain the greater degree of membrane perturbation seen in the present case and support the idea that CDA II may embrace more than one disease entity.
A primary objective, realized in this study, was the preparation from avian erythroid cells of chromatin free of contaminating membrane, as a prerequisiste to the study of chromatin acidic proteins from cells throughout the maturation pathway. Cells are lysed in saponin (S), washed in Nonidet-P40 (N), and plasma membrane removed by high-speed rotating knives (K). Purified SNK nuclear bodies are recovered free of membrane after centrifugation through 2.35 M sucrose. The chromatin acidic proteins from such preparations of the three major avian erythroid cell types were studied. Reticulocyte SNK chromatin was compared with reticulocyte chromatin derived from saponin lysis of cells and subsequent dispersion in EDTA solutions (Harlow et al. (1972), Cell Differ. 2, 341). The dispersed preparation has a lower acidic protein/DNA ratio, but the pattern of these proteins is more complex, presumably due to the contaminating membrane. In examining SNK acidic proteins throughout the maturation pathway it is clear that there are quantitative and qualitative differences. In the dividing erythroblast, the pattern of proteins is complex and the amount relative to DNA is 1.25:1.0. For nondividing, but transcriptionally active reticulocytes and also for transcriptionally inactive erythrocytes, the pattern is very much simpler, being dominated by three bands visible on sodium dodecyl sulfate polyacrylamide gels. The ratios of chromatin acidic proteins in these preparations relative to DNA are 0.69:1.0 and 0.36:1.0, respectively. These results, obtained with purified populations of cells from a single cell line, indicate a strong positive correlation between the transcriptional activity of the cell and both the amount and complexity of non-histone proteins associated with chromatin. The correlation does not indicate whether the proteins are the cause or result of increased transcription.
A rapidly fatal T-cell lymphoma developed in a 25-year-old man who, over a period of seven years, had been treated with radiotherapy and combination chemotherapy for Hodgkin's disease (HD). Non-Hodgkin's lymphoma (NHL) is increasingly being recognized as a late sequel of therapy for HD, but this is the first case in which NHL of T-cell type has been identified in such circumstances.Cancer 48:1586-1589, 1981.OR SOME YEARS it has been recognized that pa-
Case ReportIn June 1972. a man then aged 18 presented with an enlarged left cervical lymph node. Investigations, including staging laparotomy with splenectomy, showed him to have nodular sclerosing HD. Stage 111,A (Fig. I ) . He was initially treated with six courses of quadruple chemotherapy (mustine hydrochloride, vincristine, procarbazine. and pred-
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