Biomedical subjects

R Barresi

Publications and source records attributed to R Barresi.

27 records · Page 2Linked to original sources

PubMed1985

Demonstration of phosphoglucomutase 1 in a subclone of the K-562 cell line.

Phosphoglucomutase 1, an enzyme mapping on the short arms of chromosome 1, is constantly missing in the leukemic cell line K-562 in spite of the presence of three No. 1 chromosomes. In the present work, a subclone of the cell line, K-562 (S)P, is described, where the enzyme can be demonstrated, thus excluding a small deletion as the cause for the lack of expression of phosphoglucomutase 1. The relationship between the presence of the enzyme and the karyotype changes in this subclone is analyzed. Addition of several inducers to the standard K-562 line failed to elicit expression of the enzyme.

Cell Line↗

PubMed1984

Regulation of acetylcholinesterase expression in the K-562 cell line.

Acetylcholinesterase, an erythroid marker constitutively expressed in K-562 cells, can be further induced by sodium butyrate. The highest level of acetylcholinesterase induction is reached in approximately equal to 3 days, in parallel with increased hemoglobin expression. Acetylcholinesterase induction is reversible, and repeated addition of butyrate is necessary to maintain a high level of the enzyme. Actinomycin D inhibits the induction.

Acetylcholinesterase↗

PubMed1983

Fibroblastoid colony-forming cells in myeloproliferative disorders.

The properties of human bone marrow fibroblastoid colonies (CFU-F) were studied in normal subjects and in patients with myeloproliferative disorders. Colony incidence was within normal values in all groups of patients analyzed except for myelodisplastic syndromes, with higher mean value. The growth rate of CFU-F is inversely related to the initial colony-forming efficiency both in normal subjects and in patients. Direct correlation between CFU-F and granulocyte-macrophage colony-forming unit (GM-CFU) was detected only in normal subjects, but lacked in patients. Higher number of CFU-F was observed in subjects with increased incidence of bone marrow megakaryocytes or peripheral blood platelets, irrespective of the underlying disorders and the platelet-derived growth-factorenhanced cloning efficiency of bone marrow fibroblasts.

Blood Platelets↗

PubMed1983

Expression of erythroid acetylcholinesterase in the K-562 leukemia cell line.

Differentiation-dependent expression of enzyme loci was evaluated in two human leukemic cell lines, the pluripotent leukemia cell line K-562 and the promyelocytic-like cell line HL-60. Acetylcholinesterase, a marker of erythroid differentiation, was present in K-562 cells and absent in HL-60 cells. This difference between the two lines was apparently unrelated to dosage effect; other enzymes carried on trisomic chromosomes in K-562 cells did not show dosage effect. Acetylcholinesterase activity was higher in subclone K-562 (S), which shows higher expression of hemoglobin. Electrophoretic mobility of acetylcholinesterase from K-562 (S) was of fetal type.

Acetylcholinesterase↗

PubMed1981

Urinary granulopoietic activity in chronic myelogenous leukemia: follow-up and correlation with various phases of the disease.

Daily urinary colony-stimulating factor (CSF) output was tested in 16 patients with chronic myeloid leukemia, 12 of which were in stable phase and 4 in blast crisis of the disease. The CSF of stable-phase patients varied within normal range, while all patients in blast crisis had values lower than normal. Also the number of CFUC ranged within normal values in stable-phase patients, while no colony growth was detectable in blast-crisis patients. Sequential studies (28 or 11 months) of 2 patients revealed an inverse relation between daily urinary CSF and presence of peripheral immature or blast cells in the patient in stable or blast phase, respectively.

Adult↗

PubMed1981

Urinary colony-stimulating factor in acute leukemia follow-up and correlation with various phases of the disease.

Urinary colony-stimulating factor (CSF) was assayed in 19 patients with various leukemias and was monitored in various phases of acute leukemia in 3 patients. Significantly higher CSF levels were found at the onset of leukemia with a monoblastic component. Continuous monitoring of CSF in a patient with acute myelomonocytic leukemia revealed a decrease in CSF level during the remission phase, followed by a rebound to high levels preceding the clinical and hematological relapse. Concomitantly, a colony-inhibitory factor (CIF) was detected. Both CSF and CIF of this patient were isolated and partially characterized.

Acute Disease↗

PubMed1981

Marrow colony stimulating activity in chronic myelogenous leukemia.

Colony stimulating activity (CSA) from bone marrow adherent cells was tested in various myeloproliferative disorders in comparison with chronic myelogenous leukemia (CML). A higher level of medullary CSA was found in acute leukemias with monoblastic component, as contrasted with low values in other acute non lymphocytic leukemias (ANLL). In CML, while the majority of patients had CSA values within normal interval, few patients had consistently higher level of this activity. Comparative analysis of growth pattern in agar or in liquid culture suggests that significant increase in medullary CSA production can be related to an abnormal regulation of granulopoiesis.

Bone Marrow↗

PubMed1980

Preparation of colony stimulating activity from human leukemic urine: hydrophobic chromatography on propylamine-agarose.

Urinary colony stimulating factor (CSF) from human leukemic urine is retained on propylamine-agarose hydrophobic chromatography; about 70% of total activity is eluted by the addition of 1 M NaCl with significant increase in specific activity. Incomplete binding of urinary CSF to this resin further confirm that biological activity is a heterogeneous pool of different molecular species. Analysis of the macro- and microscopic composition of colonies indicates that CSF resulting from this purification step maintains the ability to stimulate both granulocytic and macrophage progenitors.

Chromatography, Agarose↗

PubMed1979

Composition of human granulocytic colonies as a function of the purification stage of CSF.

Granulopoietic colonies grown in presence of human placental conditioned medium (HPCM), before and after partial purification, were characterized in terms of number of colonies, colony size and cellular composition. Our data demonstrate that the removal of inhibitors present in crude HPCM preparations results in a higher number of CFUC which are wider in size and with different cellular composition.

Bone Marrow Cells↗