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Biomedical subjects

M Pederson

Publications and source records attributed to M Pederson.

5 recordsLinked to original sources
PubMed1989

Genotoxicity evaluation in patients on phenobarbital monotherapy by sister chromatid exchange.

The potential of phenobarbital to interact with DNA has been studied using the sister chromatid exchange (SCE) assay in peripheral lymphocytes of nine adult male patients with epilepsy and of their matched controls. All patients were otherwise healthy individuals, treated chronically with phenobarbital in monotherapy. No statistically significant differences in SCE levels were found between the patient and control groups. Smoking was associated with increased SCE frequencies. The experiment was repeated with five available patients, using a slightly modified methodology. Although different SCE scores were obtained, the results of both tests were comparable.

Adult↗
PubMed1980

Immunologic phenotype in 30 patients with diffuse large-cell lymphoma.

Frozen sections of 30 diffuse large-cell ("histiocytic") lymphomas that had arisen in both nodal and extranodal sites were stained with immunoglobulin light-chain and heavy-chain reagents, with nonoclonal antibodies to THAT HAD ARISEN IN BOTH NODAL AND EXTRANODAL SITES WERE STAINED WITH IMMUNOGLOBULIN LIGHT-CHAIN AND HEAVY-CHAIN REAGENTS, WITH MONOCLONAL ANTIBODIES TO T and B-cell antigens, and with an esterase marker for macrophages. Fourteen lymphomas expressed immunoglobulin light chains and were shown to be monoclonal; F(ab')2 fragments were sometimes necessary to demonstrate their monoclonal nature. Mu (IgM) was the most frequently expressed heavy chain, but in many patients other heavy chains were found. None of the lymphomas stained with T-cell antibodies or the esterase; 15 did not stain for immunoglobulin, but 13 of these 15 did express Ia antigen. These immunologic markers identified eight different phenotypes. Retrospective clinical analysis of the patients suggested that those who were immunoglobulin-positive had more advanced disease and shorter survival, but confirmation of the clinical relevance of immunologic phenotype will require prospective studies.

Adult↗
PubMed1978

A study of lymphoproliferative diseases comparing immunofluorescence with immunohistochemistry.

Sections of lymph nodes from patients with lymphoproliferative disorders were stained by immunofluorescence and immunoperoxidase methods. Staining with anti-kappa and anti-lambda antibodies employed F(ab')2 fragments of purified antibodies to avoid binding via Fc receptors. Frozen-section immunofluorescence revealed that B-cell lymphomas were composed of monoclonal populations of Ig-bearing cells. With immunohistochemical technics, however, a significant number of B-cell lymphomas either did not stain for Ig or showed spurious staining. The possible reasons for lack of staining in some cases and spurious staining in others are discussed. As currently applied to lymphoproliferative disorders, immunofluorescence appears to be more senitive and more speific than immunohistochemistry.

Cell Transformation, Neoplastic↗
PubMedDate not supplied

Comparative effects of phenytoin and/or phenobarbital treatment on sister chromatid exchange.

The potential of the widely prescribed antiepileptic drugs (AEDs) phenytoin (PHT) and phenobarbital (PB) to interact with genetic material was tested using sister chromatid exchange (SCE) assay. Thirty adult male patients with epilepsy receiving long-term AED therapy (16 with PHT, 6 with PB, and 8 with combined PHT and PB therapy) and 30 healthy controls were selected for the study of SCE frequencies in peripheral lymphocytes. The patients and controls were carefully screened and matched for sex, age, and smoking habits. All potential probands with exposure to factors known or suspected of affecting the SCE frequencies were excluded. Statistical analyses did not show any significant differences between the SCE rates of PHT- and/or PB-treated patients and controls, indicating a lack of mutagenicity of the tested drugs as expressed by induction of SCE on adult recipients. Smoking, however, affected the SCE levels considerably. The smokers had higher SCE frequencies than the nonsmokers, both among patients and controls. Caffeine consumption was also associated with SCE increases in patients but not in controls.

Adult↗