Search PubMed⌕ Search

Biomedical subjects

M Bertini

Publications and source records attributed to M Bertini.

At least 91 records · Page 5Linked to original sources
PubMed1982

Immune complexes and circulating antibodies against autologous leukaemic cells in patients with acute leukaemias.

Serum of patients with different forms of acute leukaemias were analysed either for the presence of circulating antibodies against autologous leukaemic cells or for that of soluble immune complexes. At the moment of their diagnosis, twelve of twenty-five patients with different types of leukaemias, showed circulating serum immunoglobulins capable of binding to the leukaemic cell surface (LCS). These anti-LCS immunoglobulins were of the IgG class and were detectable by a binding assay employing glutaraldehyde-fixed target cells and radioiodinated Staphylococcus aureus Protein A. Their digestion with pepsin showed that the site involved in the binding was in the F(ab')2 fragment. The anti-LCS immunoglobulins were observed in patients with non-lymphatic leukaemias but not in the four cases of acute lymphocytic leukaemia studied. Forty percent of the patients with anti-LCS immunoglobulins had high levels of circulating immune complexes, detectable by a competitive test with bovine conglutinin and an enzymatically-active antigen-antibody probe. After cytostatic chemotherapy, the level of circulating immune complexes decreased in all the patients, while the anti-LCS immunoglobulins remained constantly detectable and appeared also in those who were negative at the day of the diagnosis.

Adolescent↗
PubMed1981

Independence of REM density from other REM sleep parameters before and after REM deprivation.

The aim of our work was to investigate the interrelationships among rapid eye movement (REM) percent, latency, and density and their variations during different nights in an adequate REM-deprivation study. Twenty male subjects slept for 7 consecutive nights in the laboratory: 2 adaptation, 1 base line, 2 deprivation, and 2 recovery. Wilcoxon's test showed a significant increase in REM percent and a decrease in REM latency from base line to recovery nights. REM density on the contrary showed a decrease, possibly due to dilution caused by increased time spent in stage REM. Eye movement activity appears to remain stable after REM deprivation. Furthermore, REM density showed no correlation with other REM sleep measures, while its highly significant correlations across nights make it a reliable and stable descriptor of an individual's sleep pattern. The independence of eye movement activity with respect to other parameters of REM sleep is suggested.

Adolescent↗
PubMed1978

Tumor-specific and tumor-associated membrane antigens of Rous sarcoma virus transformed hamster fibroblasts.

Hamster fibroblasts transformed by an env- strain of Rous sarcoma virus (RSV) express at their surface tumor-associated antigens of unknown origin and a tumor-specific antigen (VCSA) which is not expressed by hamster fibroblasts transformed by unrelated DNA or RNA oncogenic viruses. This antigen was detectable by rabbit antibodies and a complement-dependent 51Cr-release cytotoxicity assay and is common to RSV-transformed cells of different animal species. By comparing the anti-VCSA serum which antisera directed against purified gp85, gs-proteins, reverse transcriptase or detergentlysed virus particles, it was shown that VCSA is not a known virion structural protein. Moreover, VCSA expression does not correlate with viral replication since it is not detectable in chick embryo fibroblasts productively infected with the transformation-defective virus RAV-1 which shares virus structural genes with RSV. Finally, in hamster cells transformed by an RSV mutant, temperature-sensitive for the ability to transform the host cell, VCSA expression at the cell surface correlates with the expression of the transforming gene.

Animals↗
PubMed1978

Immunochemical purification of probe-labeled plasma membrane proteins: an approach to the molecular anatomy of the cell surface.

The probe 2,4,6-trinitrobenzene sodium sulfonate may be used under appropriate conditions for selective labeling of plasma membrane proteins exposed at the outer cell surface. Labeled proteins, solubilized by detergents, can be purified by reverse immunoadsorption using antiprobe antibodies covalently linked to Sepharose 4B. This method has been applied to an investigation of the outer cell surface structure of chicken embryo and hamster fibroblasts. Coelectrophoresis in sodium dodecyl sulfate-polyacrylamide gels of probe-labeled membrane proteins purified from baby hamster kidney fibroblasts have shown that 7 major protein groups of different molecular weight are exposed on both control and Rous sarcoma or polyoma virus-transformed cells. Moreover, the transformed cells display a nonvirion component of 80--100 k daltons that is not labeled by the probe in normal cells. In fibroblasts transformed by a temperature sensitive Rous sarcoma virus mutant, that transforms at 37 degrees C but not at 41 degrees C, the expression of this component is related to the expression of the transformed phenotype.

Animals↗
PubMed1975

Evidence for a membrane carrier molecule common to embryonal and tumour-specific antigenic determinants expressed by a mouse transplantable tumour.

Rabbits were primed with membrane antigens solubilized from BALB/c embryo cells. After boosting with membrane antigens solubilized from a syngeneic transplantable adenocarcinoma, they developed a 'secondary' response against tumour-specific antigenic determinants. The antibodies against these determinants neither reacted with nor were absorbed by the antigens prepared from embryonal cells. However, the antigen displaying the tumour-specific determinants was bound by a reversed immunoadsorbent of insoluble anti-embryo antibodies. Indirect immunofluorescence experiments performed on adenocarcinoma cells in culture showed that, under conditions where redistribution of cell membrane components was induced, the anti-embryo antiserum aggregated the tumour-specific determinants. The purification of embryo and tumour-specific antigens achieved by affinity chromatography on insoluble antibody columns yielded three polypeptides of molecular weight close to 25,000, 20,000, and 10,000 Daltons respectively. It is suggested that the antigenic determinants responsible for tumour and embryo specificities in adenocarcinoma were located on the same molecule, or, more likely, on molecules which are closely associated in the plasma membrane and that do not dissociated in bile salts.

Adenocarcinoma↗