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R Ruvidić

Publications and source records attributed to R Ruvidić.

At least 19 recordsLinked to original sources
PubMed1990

Drug-induced agranulocytosis: bone marrow granulocytic progenitor cells.

Bone marrow CFU-GM and cluster forming cells were studied in ten patients in different stages of drug-induced agranulocytosis using a methylcellulose cell culture technique in vitro. In the aplastic phase of the disease (A), the number of both CFU-GM and cluster forming cells was decreased in comparison to normal values. In the regenerative phase of the disease (R), the number of both granulocytic progenitors increased but did not reach normal values. In patients considered to be recovered from acute agranulocytosis (Rec), a decreased number of progenitors persisted indicating residual damage at this granulocytic cell level. It is suggested that agranulocytosis is due to isolated damage of granulocytic cells and predictable cascade of events within different cell compartments could be used as an in vivo model for investigation of the regulation of granulopoiesis.

Agranulocytosis↗
PubMed1990

Endogenous BFU-E in peripheral blood in diagnosis of polycythemia vera.

Erythroid progenitors (CFU-E and BFU-E) growth in vitro from bone marrow and peripheral blood of patients with polycythemia vera (PV) was studied using a methylcellulose culture technique. The aim of the study was to find out whether the in vitro colony formation of peripheral blood could be used in the differential diagnosis of PV. In all 25 patients studied, endogenous colonies were found in the bone marrow and peripheral blood. The parallel study of both bone marrow and peripheral blood erythroid progenitors indicates that the presence of endogenous BFU-E in peripheral blood is a dependable test for PV. The results presented here showed that the abnormalities in PV erythroid progenitors are expressed at the level of both CFU-E and BFU-E, suggesting multiple changes in the erythroid progenitors. Our finding indicate that peripheral blood BFU-E differ from bone marrow BFU-E with regard to their dependence for further differentiation on BPA, the activity present in PHA-LCM.

Adult↗
PubMed1990

Erythropoiesis in paroxysmal nocturnal hemoglobinuria.

Ten patients with paroxysmal nocturnal hemoglobinuria were studied. The diagnosis was made on the basis of hemolytic anemia, a positive Ham test and hemosiderinuria. Six patients had primary paroxysmal nocturnal hemoglobinuria evolved from aplastic anemia. These four patients also had a milder form of the disease, Over long periods of the follow-up, large variations of hemoglobin values and red blood cell counts were observed. Both absolute and percent reticulocyte counts were increased. Erythroblast counts in the bone marrow were 3-5 times higher than normal. Reticulocyte counts in the bone marrow were 3-5 times higher than normal. Reticulocyte counts showed wide variations but substantially smaller than those in autoimmune hemolytic anemias. Serum iron was either normal or increased, while the bone marrow iron store was high or low. However, the finding of urinary hemosiderin in all cases spoke against depletion of iron stores. The red blood cell life span was moderately shortened. Kinetic studies with 59Fe showed a high red blood cell iron incorporation, while the curves frequently had irregular shapes (broken curve) or an early, abrupt fall. Studies of late erythroid progenitors (CFU-E) indicated that this compartment was preserved. Even after long observation periods was no stem cell pool depletion due to an increased red blood cell demand observed.

Anemia, Aplastic↗
PubMed1986

Acute erythremic myelosis (DiGuglielmo) following atypical aplastic anemia.

A patient presented with acute erythromyelosis (DiGuglielmo) which was developed after 3 yr of aplastic anemia. Aplastic anemia differed from the classical form, since erythroid cells and megakaryocytes were relatively preserved in the bone marrow. Treatment with androgens induced the increase of hematocrit and reticulocyte as well as general improvement. The sudden appearance of hemorrhagic syndrome due to thrombocytopenia was associated with aggravation of anemia and granulocytopenia. In the bone marrow, giant multinuclear proerythroblasts with bizarre nuclear morphology and PAS positivity with coarse granules was found. Serum erythropoietin (Ep) level was high. Bone marrow cells culture in vitro revealed two types of erythroid colonies: typical and giant multinuclear cells, both benzidine-positive. The number of colonies was irrespective to the Ep dose. "Autonomous" Ep independent growth of these colonies was also demonstrated. The number of colonies was more than 3 times higher per number of cells seeded when compared to normals, which indicated malignant proliferation and Ep independent growth. Treatment with 6-mercaptopurine and transfusions was without effect and the patient died after 15 days with signs of cerebral bleeding.

Acute Disease↗
PubMed1985

Myelopoiesis and erythropoiesis of bone marrow cells cultured in vitro in patients recovered from aplastic anaemia.

Methylcellulose culture assay was used to detect committed haemopoietic stem cells, CFU-C and CFU-E, in aplastic anaemia patients with autologous haemopoietic reconstitution. Severe diminution of CFU-C was found in all the patients studied and the absence of a dose-response to colony stimulating factor (CSF) was demonstrated. A reduced number of CFU-E and lower erythropoietin (Ep) sensitivity of those progenitors was detected as well. Autologous serum added to the bone marrow cultures of these patients enhanced the growth of CFU-C but inhibited CFU-E growth. According to the results presented, some residual damage at the stem cell level is suggested.

Adult↗
PubMed1985

A study of disturbances in granulocytopoiesis in humans using a diffusion chamber system.

Data are presented demonstrating that bone marrow granulocytic cells from normal persons continuously proliferate and mature during 5 d of cultivation in a diffusion chamber system (DC). Bone marrow granulocytopoiesis in 3 patients with different granulocytopoietic disorders was investigated using DC. In patient 1, with drug-induced agranulocytosis, bone marrow aspirated on the "day of recovery" revealed intensive proliferation in DC resulting in a highly significant increase of mature granulocytes. Patient 2 suffered from chronic neutropenia of unknown aetiology. After 5 d cultivation of bone marrow in DC an increase of metamyelocytes was observed, indicating delayed maturation of granulocytic cells. Patient 3 had neutropenia probably due to the splenic sequestration. Data obtained with DC suggest stimulated granulocytopoiesis in this patient. The results obtained using DC reflect the particular phase of the disease in which bone marrow was aspirated. It may be concluded that this method could provide additional data in quantitative and functional disorders of granulocytes.

Adolescent↗
PubMed1983

[Immunoneutropenia].

A patient with two episodes of acute agranulocytosis was described. Recovery was followed by an unusually slow increase in the number of peripheral blood granulocytes in spite of the presence of granulocyte precursors in the bone marrow. High level of circulating immune complexes as well as an increased number of immunoglobulins on the surface of granulocyte membrane was demonstrated throughout the course of the disease. When the level of CIC and the number of Ig-NG decreased and attained normal values, the number of granulocytes increased rapidly. The possibility that immune complexes were responsible for this neutropenia was suggested.

Adult↗
PubMed1979

Erythropoietin in patients with anaemia in rheumatoid arthritis.

Iron status and erythropoietin (Ep) level in serum and urine were determined in 30 patients with anaemia in rheumatoid arthritis. The anaemia in these patients was mild and fulfilled the criteria for anaemia of chronic disorders. The iron status of these patients differed from the iron status in patients with sideropenic anaemia. Serum Ep, level, measured indirectly by the polycythaemic mouse bioassay, was either not detected or when detected it did not correspond to the degree of anaemia. The data suggest that the failure to produce sufficient amount of Ep, among other causes, could be important in the pathogenesis of anaemia in rheumatoid arthritis.

Adult↗