We describe here a family with autosomal dominant erythrocytosis. In in vitro cultures, performed using the methyl cellulose assay, the number of erythroid colonies was normal or marginally increased when a standard concentration of erythropoietin (Epo) was used, but at lower Epo concentrations, the investigated persons formed more colonies than the controls. The difference was generally greate...

To investigate the consequences of inborn excessive erythrocytosis, we made use of our transgenic mouse line (tg6) that constitutively overexpresses erythropoietin (Epo) in a hypoxia-independent manner, thereby reaching hematocrit levels of up to 0.89. We detected expression of human Epo in the brain and, to a lesser extent, in the lung but not in the heart, kidney, or liver of tg6 mice. Althou...

Background. Paraneoplastic syndromes (PNS) such as hypercalcaemia, hypercholesterolaemia, and erythrocytosis have been described in hepatocellular carcinoma (HCC). Aims. (1) To examine the prevalence, clinical characteristics, and survival of PNS in HCC patients and (2) to evaluate the extent to which each individual PNS impacts on patient survival. Methods. We prospectively evaluated the preva...

RYTHROPOIETIN (Ep) is a glycoprotein hormone E produced mainly by the kidney and is the principle regulator of erythropoiesis.' The level of Ep is normally tightly controlled and helps to maintain a relatively constant red blood cell (RBC) mass.' Occasionally, abnormal production of Ep results in secondary erythrocytosis. Secondary erythrocytosis has been reported in a variety of tumors includi...

I read with great interest the recent paper of Gordeuk et al. on congenital polycythemias/erythrocytoses, in which a diagnostic algorithm based on serum erythropoietin (Epo) concentration in non-phlebotomized patients is presented. As a first step the authors propose classification into primary erythrocytosis (increased red cell mass due to intrinsically abnormal bone marrow erythropoiesis) ver...

OBJECTIVE Myeloproliferative neoplasms (MPNs) like essential thrombocythemia (ET), polycythemia vera (PV), and primary myelofibrosis (PMF) are acquired clonal hematopoietic stem cell disorders and originate from a multipotent hematopoietic stem cell. The SOCS1 and SOCS3 genes are negative regulators of the JAK/STAT signal pathway. In this study we investigate the promoter methylation of these g...

Erythrocytosis was induced in Fischer rats by intrarenal (ir) injection of nickel subsulfide (Ni3S2) in dosages ranging from 0.6 to 10 mg per rat. Measurements of blood packed cell volume (PCV) became increased by one month after ir injection of Ni3S2; reached maximum values at approximately two months; and gradually returned to control values by seven months. The duration and magnitude of eryt...

Excessive erythrocytosis results in severely increased blood viscosity, which may have significant detrimental effects on endothelial cells and, ultimately, function of the vascular endothelium. Because blood-brain barrier stability is crucial for normal physiological function, we used our previously characterized erythropoietin-overexpressing transgenic (tg6) mouse line (which has a hematocrit...