Extramedullary Haematopoiesis (extramedullary + haematopoiesi)

Distribution by Scientific Domains


Selected Abstracts


Extramedullary haematopoiesis surrounding the pituitary gland after cord blood transplantation

NEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 2 2007
E. Kusumi
No abstract is available for this article. [source]


Epidural extramedullary haemopoiesis in thalassaemia

JOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 2 2002
Süreyya Boyacigil
SUMMARY Intrathoracic extramedullary haematopoiesis is a rare condition. Involvement of the spinal epidural space with haematopoietic tissue is rather unusual. A 31-year-old-man with a known diagnosis of ,-thalassaemia was referred with focal back pain. Magnetic resonance imaging revealed diffuse bone-marrow changes, thoracic paraspinal masses and lobulated epidural masses, suggesting extramedullary haemopoiesis. The patient was treated with radiotherapy and blood transfusions. Follow-up MRI was performed for evaluation efficacy of the treatment. [source]


Chronic Pharmacological and Safety Evaluation of HematideÔ, a PEGylated Peptidic Erythropoiesis-Stimulating Agent, in Rodents

BASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 2 2009
Kathryn W. Woodburn
To support the safety of long-term dosing of chronic renal failure patients, a comprehensive toxicology programme was implemented including rat subchronic and chronic studies. Rats were administered 0, 0.1, 1 and 10 mg/kg of Hematide every 3 weeks for 3 months via subcutaneous injection or for 6 months via intravenous injection. The dosing period was followed by a 6-week follow-up period. The primary pharmacology of Hematide resulted in erythroid polycythemia as measured by elevated haemoglobin levels that were time- and dose-dependent. The pharmacology profiles were similar regardless of administration route. For example, for male rats at Day 90, subcutaneous dosing resulted in haemoglobin increases of 2.7, 4.5 and 6.9 g/dl for 0.1, 1 and 10 mg Hematide/kg respectively, compared to 2.8, 5.7 and 7.4 g/dl increases for intravenous dosing. Histopathological changes were related to the prolonged severe polycythemia induced in normocythemic animals administered an erythropoiesis-stimulating agent. The findings included extramedullary haematopoiesis in the spleen and liver, bone marrow hypercellularity and organ congestion. Microscopic findings were reversible, demonstrating a return towards control findings within 6 weeks following cessation of dosing. Systemic exposures, based on both area under the curve (AUC) and maximum concentration (Cmax), were substantially greater for intravenous than subcutaneous administration. No Hematide-specific antibodies were detected. In conclusion, Hematide is a potent erythropoiesis-stimulating agent, and the studies provide support for the safety of clinical development, including chronic dosing, for the treatment of anaemia associated with chronic renal failure. [source]


Incidental discovery of presacral tumour in a healthy patient: extramedullary haematopoiesis caused by a sacral fracture?

BRITISH JOURNAL OF HAEMATOLOGY, Issue 1 2006
Natasha Forster
No abstract is available for this article. [source]


Spleen neoangiogenesis in patients with myelofibrosis with myeloid metaplasia

BRITISH JOURNAL OF HAEMATOLOGY, Issue 5 2004
Giovanni Barosi
Summary Neoangiogenesis is an integral component of bone marrow myeloproliferation in patients with myelofibrosis with myeloid metaplasia (MMM). As extramedullary haematopoiesis is a constitutive feature of MMM, we studied spleen neoangiogenesis by a computerized image analysis in MMM patients. Compared with five normal subjects, spleen CD34-staining capillary vascular density (CVD) was 2·1,3·03 times higher than the upper range of normal in six of the 15 (40%) MMM patients. CD8-staining sinusoidal vascular density (SVD) was constantly normal or lesser than normal and was inversely correlated with CVD (R = ,0·53; P = 0·04). In MMM patients who did not receive cytoreductive or radiation therapy in the month before splenectomy (n = 9), the CVD was a significant determinant of spleen size (R = 0·88; P = 0·04). In MMM patients, the number of spleen CD34+ haematopoietic stem cells was increased from 1·2 to 98 times the upper limit of normal, and predicted the expansion of CVD (R = 0·57; P = 0·03). A population of cells expressing the CD34+/CD133+/VEGFR-2+ angiopoietic phenotype was present in the blood and spleen of five of seven patients. These results document that neoangiogenesis is an integral component of spleen re-localization of haematopoietic stem cells and suggest a cellular mechanism for spleen neoangiogenesis. [source]