Among 761 consecutive patients with chronic myeloproliferative disorders (CMD), it was found that 18 (nine men and nine women) did not fulfill at presentation the established diagnostic criteria for ...the typical forms. In seven patients, the diagnosis of CMD was made on the basis of an intense and persistent thrombocytosis that complicated splenectomy. The other 11 patients had various combinations of the following signs suggesting CMD: splenomegaly, bone marrow myeloid hyperplasia and/or slight myelofibrosis, mild thrombocytosis and/or leukocytosis, and rare immature myeloid cells in the peripheral blood. All patients were younger than 46 years of age (median age, 31.5 years; range, 20 to 45 years). A major thrombotic event was the most frequent presenting feature (eight of 18 cases), and thrombotic complications supervened in seven of the eight splenectomized patients (six in the portal system), raising the overall rate of patients with thrombotic events in their history to 11 of 18. At a median follow‐up of 50 months (range, 24 to 241 months), three patients had died of thrombotic complications (two after splenectomy). The 15 surviving patients had stable disease, and 12 of them were not receiving cytoreductive therapy. Spontaneous growth of circulating burst‐forming units erythroid was demonstrated in one patient, and erythroid responsiveness to erythropoietin appeared higher than in the normal controls in four. Spontaneous in vitro platelet aggregation in whole blood and/or platelet‐rich plasma was seen in five of seven patients. It was concluded that a difficult to identify, slowly progressive form of CMD occurs in young people, that it carries a high risk of thrombosis, and that splenectomy is a high risk procedure in these cases. Cancer 68:2310–2318, 1991.
Glycopeptides were extracted by papain digestion from old and young human erythrocyte membranes and fractionated on DEAE-Sephadex A-25. Chemical characterization of the unfractionated samples and of ...the main peak eluted from the column indicates that glycoproteins of the erythrocyte membrane undergo significant decreases in sialic acid and galactosamine content with aging.
Erythrocyte membrane glycoproteins undergo various types of modification during the life of the cell in the circulation; when only sialic acid is removed, the younger red cells can be repaired in the ...liver and return to the circulation. Otherwise, when an autolytic mechanism removing a sialopeptide becomes active as a consequence of the metabolic impairment of the cell, the erythrocyte is probably trapped by the hemocatheretic organs and destroyed.
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