Kapronczay Károly szerk.: Orvostörténeti közlemények 230-233. (Budapest, 2015)
KÖZLEMÉNYEK - Elek Gábor—Müller Miklós: Bauer Ervin és a rákkutatás
88 Comm, de Hist. Artis Med. 230-233 (2015) cells), etc. Sometimes conclusions were drawn even from inanimate models (disjunction of oil-chloroform drops in the presence of soda crystals) (Spek, see Bertalanffy 1932 229; Heréik 1934 187-189). Numerous methods (staining, microscopic birefringence, microdissection by micromanipulator, deformation and sedimentation during centrifugation, swelling) indicated that density, viscosity and permeability of the cell membrane are periodically altered as division progresses. Such changes manifested as anisotropic shrinkage in solutions of various salt concentration, etc.(see Heilbrunn 1928 35-53), involving only a segment of the cell surface (Spek 1924). The plane of the cell division is the equatorial one; perpendicular to that is the polar plane. According to Spek cell division was initiated by the equatorial relaxation (swelling theory) but Heilbrunn saw polar condensation playing this role (gelifica- tion theory, Heilbrunn 1928 255-297; see Bertalanffy 1932 230-232, 287). The cell membrane was assumed to be a lipid pellicle, therefore lipid solvents and fatty acids were also used to start or influence division (Loeb 1906 245; Heilbrunn 1928 202-214). Such toxic agents could not be present continuously in all phases of the division; after short exposure they had to be washed out from the cell suspension. Esters of fatty acids were less toxic (Heilbrunn 1928 246-247). Since these were surface active materials, the question of the role of surface tension in cell division was raised. It is remarkable that the role of nucleus in cell division was not appreciated yet. Although already Boveri knew of the constant relation between chromatin and cytoplasm in the cell, the nucleus was supposed to be only an organelle of oxidation (see Loeb 1906 36, 100-101). ,.Little is known for certain about „ the role of the nucleus in the life of the cell“ (Krüger 1926) ’(quotes Bertalanffy 1932 214). Colloidal biology explained the important phenomena of cell-life by the activity of the cytoplasm (see Elek 2014). Contemporary biological theories sought the cause of cell division in some kind of short periodical stress (crisis) between the material requirement and its fulfilment that disturbs the cell’s othervise regular resting state (the equilibrium, Loeb 1906 101). ,The protoplasm... represents a complex system of equilibrium states. These are secured in a marvellous way against changes in external conditions. After conditions change, they lead to the next, equally characteristic and plasma specific equilibrium state’(Spek 1928). The successor cell was thought to begin its life at a minimum level of energy. This level increases in the course of its life because more and more energy is necessary to maintain this equilibrium. The fundamental idea behind all cell division theories was that during division energy is liberated, therefore it is a spontaneous process (Rashevsky 1960 181, 244). In consequence, the young new cell begins its life at an energy level, that is lower than where the old cell ended its life. The surface energy surplus of the successor cells (see above) was thought to be spontaneously absorbed in the stress of the cell division. Theories and treatment of cancer at the beginning of 20th century A number of agents were known even then to cause cancer: cell free filtrates of tumours in chickens (Rous 1911), chemicals: painting the skin with coal tar (Yamagiva and Ichikawa 1914), aniline dyes (bladder cancer), physical factors: radiant energy, etc. The role of some bacteria (Bacillus tumefaciens: Blumenthal) and parasites (Spiroptera neoplastica: Fibiger, etc.) could not be excluded as carcinogenic agents at that time (see Baló 1962 230,233-234, 237; Borst 1923 653-670), an assumption later proved to be erroneous. The definitive diagno
