PubMed Health⌕ Search

Biomedical subjects

L Canepa

Publications and source records attributed to L Canepa.

At least 19 recordsLinked to original sources
PubMed1996

Anaplastic large cell lymphoma: a clinicopathologic study of 53 patients.

Fifty-three consecutive cases of adult CD30+ anaplastic large cell lymphoma (ALCL) have been analyzed. Thirty-six were classified as Hodgkin's disease like variety (HL) (67%) and seventeen as so-called common type (CT) (33%). All cases strongly expressed the CD30/Ki-1 antigen; the neoplastic cells expressed CD15, CD45 and EMA in 60%, 44% and 33% of cases, respectively; T. B and null phenotypes were found in 37%, 17% and 46% of cases. Bulky mediastinal, B symptoms, and extranodal disease at diagnosis were present in 36%, 49% and 25% of cases. EBV encoded latent membrane protein (LMP-1) was found in 10 cases. Of the 13 tested cases only 4 expressed a weak positivity of the CD40 molecule, in a fraction of the tumor cells; in the same cases CD21 was never found. Patients were treated with various protocols; of the 50 evaluable patients, 39 (78%) obtained a complete remission (CR), 3 (6%) a partial remission (PR) and 8 (16%) did not respond. The projected overall disease free survival (DFS) at 36 months is 70%. Only patients with advanced disease stage (III-IV) showed a statistically decreased DFS and survival. Only symptomatic and extranodal disease significantly appeared to influence survival. This study confirms the good outcome of this group of lymphomas and differs from other reports for some clinical (lower percentage of advanced stage, extranodal disease and skin infiltration) and pathological (HL/CT ratio and immunophenotype) features.

Adult↗
PubMed1995

Fluorescence in situ hybridization provides evidence for two-step rearrangement in a masked Ph chromosome formation.

A chronic myelogenous leukemia (CML) patient with a masked Ph chromosome due to the translocation (9;10;22)(q34;q24;q11) is reported. Banding analysis showed a 9q+ chromosome typical of standard t(9;22)(q34;q11), and fluorescence in situ hybridization studies confirmed the involvement of a chromosome 10 in the masked Ph formation and also the presence of 3' ABL-DNA sequences in the der(22). This complex rearrangement could be explained by two consecutive translocations: the first, a standard t(9;22) (q34;q11), the second, a translocation between a chromosome 10 and the der(22) with a breakpoint in sequences derived from chromosome 9 telomeric to the ABL gene. By reverse transcription polymerase chain reaction (RT-PCR), we studied the BCR/ABL transcript junction: a chimeric m-RNA b3-a2, indicating a breakpoint within the major breakpoint cluster region, was found.

Adult↗
PubMed1992

Molecular analysis of clonality in plasma cell dyscrasias.

It has been suggested that multiple myeloma, generally considered a neoplastic disorder of mature plasma cells, may arise from a pluripotent haemopoietic stem cell. The possibility that circulating lymphocytes derive from the same neoplastic progenitor has been tested in a large number of studies in the past few years, as proof of the interest that this subject is raising among scientists, and also of its elusiveness. We studied a group of 29 patients with plasma cell dyscrasias in order to evaluate clonality of haemopoietic cell populations. The X-linked markers hypoxantine phosphoribosyltransferase (HPRT) and phosphoglycerate kinase (PGK) disclosed no monoclonal component in seven heterozygous women. Analysis of immunoglobulin gene rearrangement with four probes showed a germline configuration in samples from 25/29 patients. Only four bone marrow samples from subjects with aggressive disease had rearranged C mu sequence; one had rearrangement of JH and C mu.

Adult↗
PubMed1991

Bound and unbound pyridine dinucleotides in normal and glucose-6-phosphate dehydrogenase-deficient erythrocytes.

We have measured, by a sensitive cycling assay, the concentration of bound and unbound dinucleotides in normal and glucose-6-phosphate dehydrogenase (G6PD)-deficient erythrocytes. Measurement of free NADP in ultrafiltrates confirms that in normal erythrocytes almost all NADP is bound to cytosolic proteins. In glucose-6-phosphate dehydrogenase-deficient erythrocytes unbound NADP is significantly higher than in normal red cells and the NADP+/NADPH ratio is largely in favor of the oxidized form. In normal and glucose-6-phosphate dehydrogenase-deficient erythrocytes essentially all NAD (bound and unbound) is in the oxidized state. About 50% of the total amount of NAD (NAD+ + NADH) is free in the cytosol, with a NAD+/NADH ratio greater than 100.

Cytosol↗
PubMed1989

Clonal B lymphocytes lack bcr rearrangement in Ph-positive chronic myelogenous leukaemia.

Philadelphia (Ph) chromosome-positive chronic myelogenous leukaemia (CML) was studied in a subject heterozygous for the X chromosome-linked alloenzyme system of glucose-6-phosphate dehydrogenase (G6PD). Determination of G6PD mosaicism showed homogeneous expression in granulocytes, erythrocytes and platelets. Cytogenetic studies showed the typical Ph translocation in all metaphases from bone marrow and peripheral blood myeloid cells, bcr rearrangement was detected in bone marrow and in granulocytes. B cells were stimulated with Epstein-Barr virus (EBV) in order to evaluate involvement of lymphocytes, EBV-transformed lymphoblastoid cells expressed a single G6PD phenotype and therefore probably derived from the leukaemic stem cell. However they had a normal karyotype and a constitutional bcr restriction pattern. Molecular analysis in this case of CML clarifies the differentiative potential of cells belonging to the leukaemic clone, by demonstrating that clonal Ph-negative B cells maintain normal differentiative capacity and have a bcr gene sequence which is not rearranged.

B-Lymphocytes↗
PubMed1989

Molecular analysis of the bcr rearrangement in a case of Ph'-negative blastic crisis of Ph'-positive chronic myelogenous leukemia.

We describe here a patient with Ph'-positive chronic myelogenous leukemia (CML) who developed a Ph'-negative blastic crisis. The blast DNA was analyzed on two different occasions, at the beginning of the blastic phase and at the end, shortly before the patient's death. Although cells from both samples had no Ph' chromosome marker (not even a masked one) we could detect a rearrangement of the bcr gene in the second DNA sample, using a '3'-bcr' probe. The same probe and a '5'-bcr' probe failed to detect any rearranged band in the first DNA sample. No rearrangement was identified at the c-myc and N-ras loci, while a slight c-myc amplification was evident in both DNA samples tested.

Blast Crisis↗
PubMed1989

Catalase and glutathione peroxidase are equally active in detoxification of hydrogen peroxide in human erythrocytes.

Genetic deficiencies of glucose-6-phosphate dehydrogenase (G6PD) and NADPH predispose affected erythrocytes to destruction from peroxides. Conversely, genetic deficiencies of catalase do not predispose affected erythrocytes to peroxide-induced destruction. These observations have served to strengthen the assumption that the NADPH/glutathione/glutathione peroxidase pathway is the principal means for disposal of H2O2 in human erythrocytes. Recently, however, mammalian catalase was found to have tightly bound NADPH and to require NADPH for the prevention and reversal of inactivation by its toxic substrate (H2O2). Since both catalase and the glutathione pathway are dependent on NADPH for function, this finding raises the possibility that both mechanisms destroy H2O2 in human erythrocytes. A comparison of normal and acatalasemic erythrocytes in the present study indicated that catalase accounts for more than half of the destruction of H2O2 when H2O2 is generated at a rate comparable to that which leads to hemolysis in G6PD- deficient erythrocytes.

Carbon Dioxide↗
PubMed1987

A case of ataxia telangiectasia with unbalanced glucose 6-phosphate dehydrogenase mosaicism in the granulocytic/monocytic lineages.

Ataxia telangiectasia is a genetically determined disease with multi-system abnormalities and a high incidence of neoplasia. In order to define the nature of the association between ataxia telangiectasia and malignancy, we investigated a patient with the disease and heterozygote for the Mediterranean variant of the X-linked marker glucose 6-phosphate dehydrogenase. Enzymatic mosaicism in hemopoietic and nonhemopoietic cells was evaluated with the 2-deoxy glucose 6-phosphate technique. While erythrocytes, platelets, and lymphocytes expressed the same double-enzyme phenotype as tissues of nonhemopoietic origin, granulocytes and monocytes expressed almost exclusively the Mediterranean-type enzyme. We suggest that, as the result of genetic instability at the hemopoietic stem-cell level, the granulocytic/monocytic progeny enjoyed a proliferative advantage and became the predominant clone.

Ataxia Telangiectasia↗
PubMed1985

Clonal development from a progenitor with restricted differentiative expression in acute lymphoblastic leukemia.

Three patients with acute lymphoblastic leukemia (ALL) and heterozygous for the Mediterranean variant of glucose-6-phosphate dehydrogenase (G6PD) have been investigated with the 2-deoxyglucose-6-phosphate (2dG6P) method to determine the number and type of progenitor cells in which the disease arose. A monoclonal origin was established for the lymphoblasts, while the other hemopoietic cell lines were not involved in the leukemic process.

Child↗
PubMed1984

Clonal origin of cells restricted to monocytic differentiation in acute nonlymphocytic leukemia.

Two patients with acute monocytic leukemia and heterozygous for the Mediterranean variant of the X-linked enzyme, glucose-6-phosphate dehydrogenase (G6PD), were investigated to determine the number and type of progenitor cells involved. Mosaicism for Mediterranean G6PD was assessed by the different rate of utilization of 2-deoxy glucose-6-phosphate (2dG6P) by normal and Mediterranean variants of G6PD. The monocytoid blasts were found to express one type of G6PD only, indicating their clonal origin from a common progenitor cell, whereas all other hemopoietic cell populations tested expressed the heterozygous phenotype. The finding of a unique involvement of the monocytic line in two cases of acute nonlymphocytic leukemia (ANLL) represents further evidence of heterogeneity of stem cell involvement in ANLL.

Cell Differentiation↗
PubMed1983

Reexpression of normal stem cells in erythroleukemia during remission.

A patient with erythroleukemia and heterozygous for the Mediterranean variant of the X-linked enzyme glucose-6-phosphate dehydrogenase (G6PD) was studied to determine the number and type of progenitor cells in which the disease arose. G6PD mosaicism was assessed by the different rate of utilization of 2-deoxy-glucose-6-phosphate (2dG6P) by normal and Mediterranean variants of G6PD. Erythroleukemia is established as a clonal disease involving a precursor cell common to the erythroid and myeloid lines. After intensive chemotherapy, restoration of nonmonoclonal hemopoiesis is achieved, as indicated by the reappearance of the mosaic phenotype in hemopoietic cell populations.

Aged↗
PubMed1982

Primary thrombocythemia: clonal origin of platelets, erythrocytes, and granulocytes in a GdB/GdMediterranean subject.

A patient with primary thrombocythemia, who was heterozygous for glucose-6-phosphate dehydrogenase deficiency (GdB/GdMed), was investigated to test for the clonal origin of this myeloproliferative disorder. In order to assess somatic cell mosaicism in various tissues, we have made use of the different rate of utilization of 2-deoxyglucose-6-phosphate, an analog of glucose-6-phosphate, by normal glucose-6-phosphate dehydrogenase and by the Mediterranean variant: the results demonstrate that essential thrombocythemia is a clonal disease involving the erythrocytic, granulocytic, and megakaryocytic series, without affecting monocytes, T lymphocytes, and non-T lymphocytes.

Aged↗
PubMed1981

Marked karyotype abnormalities in two cases of acute myelogenous leukemia.

Two patients with acute myelogenous leukemia with severe chromosome abnormalities are described. The cytogenetic analysis shows the following karyotype: patient No. 1: 41,XY,-1,-2,-4,-5,-13,-15,-17,-18,-22,+5 markers; patient No. 2: 46,XY,-2,-5,-7,-13,+16,-21,-21,+5 markers. In each patient one set of double minute chromosomes was observed.

Aged↗
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↗
PubMedDate not supplied

Feprazone: absence of hemolytic effects in glucose-6-phosphate dehydrogenase-deficient subjects.

Some drugs, including nonsteroidal antiinflammatory compounds, can be hemolytic in glucose-6-phosphate dehydrogenase-deficient patients. We have studied the potential hemolytic activity of feprazone, a nonsteroidal antiinflammatory compound in vitro and in vivo. Agents that may be hemolytic for glucose-6-phosphate dehydrogenase-deficient erythrocytes will stimulate the hexose monophosphate shunt in normal erythrocytes. Eleven normal subjects were treated with feprazone and their erythrocytes were incubated in their own sera (containing active feprazone metabolites) and [1-14C]-glucose. Because no statistically significant increase in 14CO2 evolution was observed, 15 pediatric male patients with glucose-6-phosphate dehydrogenase deficiency who required antiinflammatory treatment were treated with feprazone. No hemolytic crises and no statistically significant changes of hematologic tests were observed.

Adolescent↗