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M Gajewski

Publications and source records attributed to M Gajewski.

22 records · Page 2Linked to original sources
PubMed1988

Influence of lipid peroxidation and hydrogen peroxide on muscarinic cholinergic receptors and ATP level in rat myocytes and lymphocytes.

Isolated rat neonatal cardiac myocytes and rat lymph-node lymphocytes were treated with Fe2+ cumene hydroperoxide or hydrogen peroxide. The intensity of lipid peroxidation was estimated by measuring production of malondialdehyde (MDA). The level of muscarinic cholinergic receptors was determined by [3H]-QNB binding. Cumene hydroperoxide treatment was found to induce lipid peroxidation in both myocytes and lymphocytes, the process being more pronounced in myocytes. An important decrease of muscarinic cholinergic receptor level and a significant drop of intracellular ATP level in these cells were simultaneously observed. In both cell types, hydrogen peroxide treatment decreased the ATP level while lipid peroxidation and muscarinic cholinergic receptors were unaffected. The different effect of hydrogen peroxide on lipid peroxidation and the level of muscarinic cholinergic receptors on the one hand and the ATP level on the other suggests that this substance acts mainly in the intracellular space.

Adenosine Triphosphate↗
PubMedDate not supplied

Automated donor-recipient identification systems as a means of reducing human error in blood transfusion.

Clerical and administrative errors are the most common mistakes in blood banking, with errors of sample or patient identification accounting for the majority of mistakes. In an effort to reduce the incidence of human errors, three automated donor-recipient identification systems were developed and were evaluated under clinical conditions. After two years of development and bench testing, each set of equipment was tested, along with established procedures, at a large clinical center, a medium-sized community hospital and a regional donor center. Although none of the systems, as tested, proved acceptable under clinical conditions, a great deal was learned about prototype equipment testing in the clinical setting. Future development of identification systems for clinical use should respond to carefully defined problems, apply in all areas of the hospital or donor center, and be convenient and reliable. The development of the equipment should involve established manufacturers and be subject to exacting preclinical testing.

Blood Banks↗
PubMedDate not supplied

Muscarinic cholinergic receptors of rat lymphocytes: effect of antigen stimulation and local brain lesion.

Expression of muscarinic cholinergic receptors (m-AchR) on thymocytes and lymphocytes supports a hypothesis of direct interaction between autonomic innervation and the immune system. Using a muscarinic antagonist, [3H]quinuclidinyl benzilate ([3H]QNB), we revealed different characteristics of m-AchR expression in lymphocytes isolated from the spleen, peripheral blood or thymus of Wistar rats. To further explore the mechanisms controlling m-AchR expression in lymphocytes we have addressed two questions: (i) whether local brain lesions will affect [3H]QNB binding activity of lymphocytes and (ii) whether different antigens will alter m-AchR expression in lymphocytes. We report here that electrolytic lesions of the area hypothalamica anterior resulted in a significant increase in [3H]QNB-specific binding in thymocytes 7 days after neurosurgery. In contrast, local lesions of other hypothalamic structures (area preoptica medialis, area hypothalamica posterior) or sensomotor cortex did not affect m-AchR expression in thymocytes. No apparent changes of [3H]QNB-binding activity were found in lymphocytes isolated from rat spleen or peripheral blood after operation. Both T-cell-dependent (sheep red blood cells) and T-cell-independent (Vi antigen of Salmonella typhi) antigens induced a significant increase in [3H]QNB-specific binding in spleen lymphocytes while [3H]QNB-binding activity of peripheral blood lymphocytes did not change. A different pattern of lymphocyte m-AchR expression found in various lymphoid tissues after immunization or brain lesions suggests a local involvement of cholinergic mechanisms in neuroimmune interaction.

Animals↗