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Biomedical subjects

M Holub

Publications and source records attributed to M Holub.

At least 109 records · Page 6Linked to original sources
PubMed1975

The polycystic organ in senescent athymic nude mice and in euthymic mice.

The polycystic organ thought to be the thymic rudiment in "athymic" nude mice increased with age and continues its secretory activity even in senescent nude mice. Only the epithelial lining of the cysts undergoes pressure atrophy. Analogous polycystic structures can be found also in euthymic mice with or without the nu gene. A lymphoepithelial rudiment is found in the thymic area of nude mice; it may represent the true endodermal thymic rudiment and generate the T cells. In addition, a peculiar, sometimes enlarged and thymus-like node is present laterocaudally from the polycystic organ.

Age Factors↗
PubMed1975

Adherent and non-adherent mouse peritoneal exudate cells.

Administration of proteose peptone to donors of peritoneal exudate cells resulted not only in quantitative increase in the mono-histiocytic cells but also in their activation as judged by their rapid adherence to surfaces, strong acid phosphatase reaction and increased numbers of lysosomes and phagocytic vacuoles. The three-hour adherent fraction of peritoneal exudate cells (from normal as well as peptone-stimulated mice) contains a large number of activated lymphocytes and fibroblastoid cells and is not enriched in macrophages. Moreover, the adherent cells, when collected by scraping, are unsuitable for immediate biological use since they lose the enzymatic equipment. For purification of histiocytes and macrophages by adherence, the 2-day cultivation of peritoneal cells was found to be optimal, as judged by the number of acid phosphatase positive cells. Their decrease after 4-day cultivation may indicate over-growth of the fibroblast and epithelial cell lineages. The non-adherent fraction was found to be enriched in lymphocytes as well as in mast cells; numerous macrophages were observed, too.

Animals↗
PubMed1975

Sesquiterpene lactones. XVI. In vitro studies on cytotoxic properties of sesquiterpene lactones in tissue cultures of human and animal malignant cells.

Cytoxicity of 18 new sesquiterpene lactones and related compounds was studied by tissue culture method using human malignant KB and HeLa cells, normal RK 13 animal cells, and by the modified plate test of Miyamura. On the basis of criteria of CCNSC HIH, USA, seven compounds with ED50 activities between 0-41 and 3-5 mug/ml were qualified for further investigation in vivo. Cytotoxic activity of sesquiterpene lactones was dependent on presence of an unsaturated lactone ring, (see article). As a rule activity of germacranolids was higher than that of guaianolides.

Animals↗
PubMed1975

Transplantation models using the regional lymph node.

Several transplantation models, using the regional lymph node, to study the transplantation reaction in strictly defined and simple conditions were devised. Lymphoid cells were transplanted to inbred rats and mice at the sites drained by one regional lymph node; the experimental design was chosen so as to permit theoretically a one-way reaction, either the host-versus-graft (HVG) or the graft-versus-host (GVH) reaction. The changes in the lymph nodes draining the site of cell injection (weight increase, histology, lymphocyte activation) were very similar in both transplantation reactions. They were ascribed to a humoral mediator released upon the contact of lymphoid cells from two genetically different individuals. The direct demonstration of a mediator which is capable of activating the regional lymph node in vivo introduces some new aspects into the process of sensitization after transplantation.

Animals↗