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Biomedical subjects

M F Martelli

Publications and source records attributed to M F Martelli.

At least 145 records · Page 8Linked to original sources
PubMed1982

The in vitro effect of a calf thymus extract (thymostimulin) on T cell phenotypes in cord blood lymphocytes.

An investigation was carried out on the in vitro effect of a calf thymus extract, thymostimulin, on the distribution of T cell phenotypes as defined by OKT3, OKT4, and OKT8 murine monoclonal antibodies and on E-rosetting cells in human cord blood lymphocytes from healthy newborns. The percentages of E-rosette-forming lymphocytes and OKT3+ total T population were lower in newborns than in adults (E-rosettes: 43.8% +/- 13% vs 57.9% +/- 7.9%, p less than 0.01; OKT3+ cells: 53.3% +/- 15.5% vs 79.9% +/- 4.7%, p less than 0.01), while the OKT4+/OKT8+ (helper/suppressor) cell ratio was normal in both (newborns: 3.40; adults: 2.44-NS). Thymostimulin increased the number of E-rosette-forming cells from 43.8% +/- 13% to 49.9% +/- 12.7% (p less than 0.01), as well as the percentage of phenotypic T lymphocytes. The highest increases were observed in the OKT4+ cells (37.7% +/- 14% to 49.1% +/- 13.8%, p less than 0.001), while smaller changes were observed in the OKT3+ cells (53.3% +/- 15.5% to 58.1% +/- 13.3%, p less than 0.02) and OKT8+ cells (12.8% +/- 6.4% to 16.6% +/- 6.5%, p less than 0.02). The results of the present study suggest that thymostimulin mainly provokes an increase in the helper T cell phenotype in cord blood lymphocytes.

Antigens, Surface↗
PubMed1981

Sideroblastic anemia associated wtih hairy cell leukemia.

A patient with leukemic reticuloendotheliosis ("hairy cell" leukemia) with sideroblastic anemia and an epinephrine-induced platelet-aggregation abnormality is presented. Immunologic membrane marker studies supported a B-lymphocyte origin of the hairy cells. It is hypothesized that a defect in the pluripotent marrow stem cell may be responsible for the hairy cell leukemia and for the intrinsic abnormalities in erythrocytes and platelets.

Aged↗
PubMed1981

Cell surface marker analysis in diagnosis of the early phase of chronic lymphocytic leukaemia.

Cell surface marker analysis was carried out in 50 CLL patients; 15 were preclinical or low count, that is with a total peripheral lymphocyte count well below 15,000/cmm and little or no infiltrative syndrome. Data of the cell surface marker in these 15 patients were compared with those of 15 patients with non-neoplastic benign lymphocytosis. Monoclonal B-cell compartment proliferation was found in low count cases, with analogous immnofunctional characteristics to typical CLL. On the other hand, there was a symmetrical increase in both T and B cell compartments in non-neoplastic lymphocytosis. This suggests that cell marker analysis is a very useful diagnostic tool during the preclinical phase of CLL, as it permits it to be readily differentiated from non-neoplastic lymphocytosis.

Aged↗
PubMed1981

Non-blastic meningeal leukemia during the myelofibrotic phase of chronic myeloid leukemia.

Myeloblastic involvement of the central nervous system has been noted in the course of chronic myeloid leukemia in the blastic phase; meningeal leukemia in the chronic phase of CML is almost unknown. We report on a case of CML in which meningeal infiltration by cells of the granulocytes series in all stage of cellular maturation developed 15 years after initial diagnosis and seven months after a myelofibrotic transformation of the systemic disease.

Adult↗
PubMed1980

Erythrophagocytosis by undifferentiated lung carcinoma cells.

A case is reported of undifferentiated metastatic lung carcinoma in which both a supraclavicular lymph node and bone marrow were infiltrated by anaplastic tumor cells which had engulfed erythrocytes and nucleated elements. The possibility of a histiocytic origin for the phagocytizing neoplastic cells was excluded by ultrastructural, cytochemical, and immunoperoxidase studies. This investigation shows that epithelial tumor cells may, at times develop phagocytizing activity, a phenomenon observed in certain experimentally induced tumors. The mechanism responsible for this phenomenon is not clear.

Bone Marrow↗
PubMed1980

Protein A-peroxidase conjugates for two-stage immunoenzyme staining of intracellular antigens in paraffin-embedded tissues.

Staphylococcal protein A conjugated to horseradish peroxidase was employed in an indirect immuno-staining technique to identify intracellular antigens in paraffin-embedded tissues. The sections were incubated with specific antisera and the antigen-IgG complexes demonstrated with protein A-peroxidase conjugate. Immunoglobulins, lysozyme and insulin were satisfactorily detected by this technique. A comparison of this method with the PAP, "labelled antigen" and peroxidase-labelled antibody sandwich techniques was made.

Antigens↗
PubMed1980

Topographical localization of intracellular immunoglobulins in hairy cells by immunoelectron microscopy.

Ultrastructural characterization and localization of intracellular immunoglobulin in peripheral blood mononuclear cells from a patient with hairy cell leukemia were studied by the direct immunoperoxidase technique. Approximately 20--30% of hairy cells stained positive for gamma-heavy and K-light chains, and this staining was limited to certain rough endoplasmic reticulum profiles. These ultrastructural findings can be considered an additional argument for the B cell origin of hairy cells.

Endoplasmic Reticulum↗
PubMed1979

[Cellular immunity in patients with Hodgkin's disease: modification induced by incubating lymphocytes with fetal calf serum and Hodgkin's serum].

The capacity of peripheral blood lymphocytes from fifteen patients with untreated Hodgkin's disease to form E-rosettes with sheep erytrocytes and to respond to PHA stimulation was found to be impaired in 47% of patients. When peripheral blood lymphocytes were incubated overnight in culture medium containing 20% fetal calf serum, E-RFC levels and the capacity to respond to PHA returned to normal. These functions were resuppressed by additional incubation with Hodgkin's disease serum but not from normal serum. The Hodgkin's disease serum inhibited normal peripheral blood lymphocytes to form E-rosettes and to respond to PHA.

Animals↗
PubMed1978

[Rosette formation test with mouse erythrocytes in chronic lymphatic leukosis: correlation with other membrane receptors].

The lymphocyte subpopulations of CLL patients have been studied. IgM and IgD membrane-associated immunoglobulins alone or in combination have been found, IgG being present in only one case. A marked increase in mouse-complement receptors (as shown by the EACt rosettes) as compared with human complement receptors (as shown by the EACa rosettes) was observed. The population of SIg-bearing lymphocytes was significantly greater than that of complement bearing lymphocytes. Moreover a mean percentage of 60.7 +/- 17 of the leukaemic lymphocytes formed rosettes with mouse red blood cells. In a significant number of patients the E-rosettes forming cells were also increased.

Erythrocytes↗
PubMed1978

Trimethoprim-induced elevation of dihydrofolate reductase activity in human leukocytes.

The administration of trimethoprim (TMP)--a diamino benzylpyrimidine compound which binds very tightly the bacterial dihydrofolate reductase--was accompanied by the appearance of measurable levels of dihydrofolate reductase in peripheral leukocytes from patients with nonhematological diseases. In all instances, enzyme activity rose rapidly between the fourth and eighth day after TMP. The time course of the rise and fall of dihydrofolate activity approaches cellular life span and is similar to that obtained after methotrexate or triamterene administration. Dihydrofolate reductases, partially purified from leukocytes of patients treated with TMP, bone marrow and leukemic leukocytes, had simila molecular weights, pH optima, Ki of inhibitor (methotrexate); they were stimulated to the same degree by KCl and urea. Electrophoresis of the enzyme on cellulose acetate strip resulted in the separation of two enzymatically active protein components. No differences in the electrophoretic behavior of the three blood cell enzymes were noted. The findings noted above are consistent with the suggestion that the observed rise in dihydrofolate reductase activity is a quantitative one. Moreover, the effect of TMP in vivo is discussed in comparison with the currently held hypothesis for methotrexate action (stabilization by the drug of a previously synthetized enzyme).

Electrophoresis, Cellulose Acetate↗