Search PubMed⌕ Search

Biomedical subjects

C Dresch

Publications and source records attributed to C Dresch.

At least 55 records · Page 3Linked to original sources

Effect of beta adrenergic agonists and beta blocking agents on hemopoiesis in human bone marrow.

The effect of propranolol (non specific blocking agent), acebutolol (beta 1 blocking agent), butoxamine (beta 2 blocking agent) and several beta adrenergic agonists was studied on 3H-thymidine (3H-TdR) incorporation and granulo-monocyte colony formation in agar by human bone marrow. Only butoxamine and propranolol decreased 3H-TdR incorporation by total normal bone marrow cells at concentrations above 10(-6) M for butoxamine and 10(-5) M for propranolol. Autoradiography showed that inhibition of 3H-TdR incorporation by butoxamine was slightly more pronounced on neutrophil precursors than on red cell precursors (neutrophil series LI..53 and erythroblasts .67 compared to control bone marrow cells at 10(-5) M concentration). The development of granulo-monocyte colonies in agar culture was delayed by preincubation with butoxamine at concentrations above 5 X 10(-6) M. Hydroxyurea suicide showed that this was due to a decrease in the number of CFU-C in S phase. beta 2 blocking agents are able to decrease the number of normal hematopoietic cells entering S phase. This effect is seen on both neutrophil and erythroblastic precursors and on granulo-monocyte progenitors. It could be used as a means of protecting bone marrow cells during cancer intensive chemotherapy.

Adrenergic beta-Agonists↗

Resistance to therapy of acute leukemia developing in the course of polycythemia vera.

Thirteen patients in whom acute leukemia developed in the course of polycythemia vera were initially treated with vincristine and prednisone in an attempt at remission induction. None responded, and four died during this initial course of therapy. Induction was then attempted in the nine survivors, using cytosine arabinoside and adriamycin. Only one complete remission of 38 weeks and one partial remission were achieved, while median survival was 32 days. Poor results may reflect both the intrinsic biologic properties of the acute leukemia occurring in this setting and the advanced age of the patients.

Acute Disease↗

Phagocytosis of neutrophil polymorphonuclears by macrophages in human bone marrow: importance in granulopoiesis.

The cytological and electron-microscopic appearance of aneutrophil phagocytosis by macrophages in normal human bone marrow is described. This feature can be observed in every normal bone marrow and is especially frequent in autoimmune disease. Bone marrrow phagocytosis of polymorphonuclear neutrophils seems to be a physiological process resulting from the random egress of neutrophils from bone marrow to blood.

Bone Marrow↗

Granulomonocyte colony-forming cells in cord blood.

The number of colony-forming cells (CFC) in cord blood has been found to be widely dispersed (478 +/- 1003/ml or 3-5200). However, a few samples (7 of 37 in this series) contained more than 478 CFC/ml and in four of these cases a history of prenatal hypertension or infection was found. In the other 30 cases the mean number of CFC was 140.6 +/- 116.9/ml blood (3-390), which, however, remains much higher than data found for adult blood. In these 30 cased the mean number of cord blood CFC in newborns of less than 37 weeks gestational age was found significantly higher (194.2 +/- 125.8/ml) than in full-term babies (99.7 +/- 93./ml, P less than 0.025). Cord blood CFC were shown to be early developing, high cycling cells. Velocity sedimentation separation showed only one population of CFC in blood with low cloning efficiency similar in size to adult blood CFC, but with a higher suicide level. Two populations of different sizes were separated in cord blood with high cloning efficiency, the larger cell population being similar to the adult bone marrow, early developing CFC. In premature newborns and in some perinatal conditions, hematopoiesis is characterized by a high level of circulating CFC with the appearance of a population of large cycling cells. The relationship between these findings and neonatal hematology is discussed.

Cell Separation↗

Hydroxyurea suicide study of the kinetic heterogeneity of colony forming cells in human bone marrow.

The kinetics of granulomonocyte colony forming cells have been studied in unfractionated normal human bone marrow by hydroxyurea suicide and in cells separated by velocity sedimentation. Sequential studies revealed two subpopulations of colony forming cells, having different sizes and different multiplication potentialities. There are large cells with a high suicide rate which develop small granulocyte and monocyte colonies during the first week of culture in semi-solid agar. Smaller cells develop larger colonies of granulocytes, monocytes and eosinophils between 2 and 3 weeks of culture. Only granulocyte progenitors have a substantial suicide rate in this small cell population. This population is also less responsive to stimulation than is the large cell class, which is a more highly differentiated progeny. The role of these different kinetics of colony forming cells is discussed in the context of the heterogeneity of the in vitro differentiation of neutrophil, monocyte and eosinophil lines.

Bone Marrow Cells↗

Maintenance therapy of 32P-induced remission in polycythemia vera. A clinical trial of chlorambucil and hydroxy-urea in 109 cases.

In 109 patients with polycythemia vera, previously treated by 32P without maintenance therapy, a trial was carried out to determine the best way to reduce the number of injections needed. Chlorambucil and hydroxy-urea have been used to lengthnen the remission. Both of them are well tolerated and compatible with follow-up at reasonable time intervals. Chlorambucil maintenance increases the mean duration of remission by 12 months, the best results being observed when the drug was used continuously, instead of an intermittent (3 consecutive days every fortnight) schedule. Hydroxy-urea does not produce statistically demonstrable advantage whatever it is given, continuously or intermittently. Our study shows that, if a long-term cooperative study of the possible advantage of maintenance therapy in P.V. was undertaken in the future, low-dosage maintenance by chlorambucil could be the treatment of choice.

Chlorambucil↗

Erythrokinetic studies in myelofibrosis: their significance for prognosis.

Eighty-three patients with myelofibrosis have been studied by erythrokinetics and have been followed up until death or for at least 12 months. Because of a large plasma volume the venous haematocrit gives only a poor idea of the red blood cell volume. The red cell survival was reduced in the majority of cases but significant haemolysis was rare. The amount of haemolysis of autologous and isologous red cells was similar, suggesting an extra-corpuscular origin for the haemolysis. Plasma iron turnover was always increased, sometimes markedly, but red cell iron incorporation was reduced in 70% of cases, indicating ineffective erythropoiesis. Surface counting showed an absence on diminution of sacral iron fixation and a rapid and marked splenic uptake in more than 90% of the cases; uptake of iron by the liver occurred in half the cases, usually not very high; iron release from the spleen was absent or reduced in 67% of the cases. The degree of ineffective erythropoiesis as measured by radio-iron incorporation and release by the spleen, the amount of haemolysis, and the red cell volume were strongly correlated with prognosis. These factors enabled a more precise prediction to be made of the clinical outcome in the 2 years following the study, than the clinical data alone. A prospective study might show whether erythrokinetic studies are also useful in determining the choice of treatment.

Aged↗

Prognostic value of in vitro bone marrow culture in refractory anaemia with excess of myeloblasts.

Bone marrow from 17 patients with refractory anaemia with excess of myeloblasts (RAEM) was cultured in methylcellulose semi-solid medium. Compared with normal bone marrow, 3 patterns of growth occurred corresponding with different clinical stages of the condition. Patients whose bone marrow grew normal colonies and those who produced a predominance of microclusters had the longest life expectance, while those who produced a predominance of macroclusters had the shortest life expectancy with a high rate of acute leukaemic transformation. Colony culture appears to be a useful prognostic tool in the condition.

Adult↗

The influence of circadian variations in plasma iron on the measure of plasma iron turnover.

In 92 cases studied in vivo with 59Fe, the variations of plasma iron during the study were measured. Errors in calculation of plasma iron turnover of up to 25% can be made in normosideremic patients if such variations are not taken into account. In hypersideremic patients the variations of plasma iron are low or nil; in hyposideremic patients the slow variations of plasma iron concentration do not alter the rapid slope of radio-iron removal.

Anemia, Hypochromic↗

[Immune deficiences during pyoderma gangrenosum associated with a polycythemia vera].

A deficiency in cellular immunity was demonstrated in a patient suffering from polycythaemia rubra vera in the myelofibrosis stage. Intradermal reactions to classical antigens (candidine, trichophytine, streptokinase, streptodornase, tuberculine) were negative, as was the di-nitrofluorobenzene test. However, the T lymphocyte count was normal. There was no disturbance in humoral immunity. Phagocytosis was normal but leucocyte migration, studied in vitro, was nil. The possibility of an intrinsic abnormality in the polynuclear neutrophil is evoked.

Adrenal Cortex Hormones↗

Cell kinetics in human cyclic neutropenia.

Cell kinetics have been studied at several periods in a patient with typical cyclic neutropenia. Peripheral blood granulocyte labelling showed an increased destruction in the preleucopenic phase. Bone marrow colony-forming cells and blood leucocyte colony forming activity were normal or above the normal range. The major abnormalities were found in sequential studies of bone marrow proliferation measured by "in vitro" 3H-thymidine flash labelling. A fall in the labelling index of promyelocytes was observed in the second part of the cycle. Incubation of normal human bone marrow cells with patient's granulocytes showed a marked decrease in 3H-thymidine incorporation, compared with incubation with the same number of normal granulocytes. Human cyclic neutropenia seems to be due to a factor secreted by abnormal polymorphonuclears inhibiting myeloid proliferation.

Adult↗

Cell culture studies in 19 cases of refractory aneamia: comparison of clinical data with in vivo erythrokinetic studies.

A total of 19 cases of chronic refractory anaemia underwent simultaneous in vivo erythrokinetic study and in vitro bone marrow culture. They were followed up clinically for at least 2 years. Good correlation has been found between erythrokinetic data (simultaneous quantitative and qualitative disorders of erythroblastic proliferation in preleukaemic states; pure qualitative disorders in primary sideroblastic anaemia) and the results of culture of granulocyte precursors in the bone marrow (small number of colonies, reduced size of colonies in preleukaemic states; normal number and growth in non malignant refractory anaemia). It would seem thus that both examinations are of practical interest in clinical haematology, making it possible to foresee the malignant evolution of some refractory anaemias.

Adult↗

Eosinophil colony formation in semisolid cultures of human bone marrow cells.

A method for in situ staining and scoring of eosinophil colonies and clusters in the whole culture dish has been developed for agar cultures of human marrow cells. Cultures stimulated by human placental conditioned medium were found to develop the same proportion of eosinophil, neutrophil, and monocyte colonies as cultures stimulated by conventional peripheral white cell underlayers. Eosinophil colonies and clusters always contained pure populations of eosinophils, and no mixed colonies of eosinophils with other cells were observed. Eosinophil colony formation was delayed in onset relative to neutrophil or monocyte colony formation, but by day 14 eosinophil colonies comprised 20% of all colonies. Eosinophil colonies were absent in cultures of marrow cells from patients with acute myeloid leukemia in relapse, but eosinophil colonies and clusters were found with higher than normal frequency in cultures from acute leukemic patients in remission. A high frequency of eosinophil colonies and clusters was also observed in cultures from three patients with idiopathic thrombocytopenic purpura. The new staining procedure should permit a wide range of studies on eosinophil precursor populations in the marrows of patients with various diseases.

Bone Marrow Cells↗

Granulopoiesis : studies of bone marrow culture in chronic granulocytopenia and comparison with granulocyte kinetics.

Granulopoiesis was studied in 20 cases of chronic granulocytopenia (adults and children; acquired and congenital). Bone marrow colony growth in methylcellulose culture was compared with the turnover-rate of blood granulocytes labelled with 51Cr and with the bone marrow granulocyte labelling index (L.I.) after "in vitro" flash labelling with 3H-thymidine (3H-TDR). There was a positive correlation between colony forming cells (C.F.C.) content and turnover rate and between C.F.C. content and bone marrow cellularity but there was no statistically valid correlation between C.F.C. content and labelling index. In patients with acquired granulocytopenia the colony counts were increased in cases with autoimmune destruction of neutrophils and in one patient during granulocytic regeneration. The C.F.C. numbers were low in cases with neutropenia associated with granulocyte hypoplasia but the prognosis was better in those cases with the highest colony count. On the other hand, colony counts were variable and had no prognostic value in cases of neutropenia secondary to a bone marrow abnormality in maturation or mutiplication, either acquired or congenital, as revealed by turnover studies and autoradiographic data.

Adolescent↗