Pathologie Der Mitose

Politzer, G.

doi:10.1097/00000441-193412000-00026

Cited by 60 publications

(7 citation statements)

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“…Agnes Bluhm (1928) discussed the role of gene mutation in tumorigenesis and reported that leading pathologists had rejected Boveri's thesis. Nevertheless, some years later, a detailed monograph on the pathology of mitosis was written by Georg Politzer (1934) in Vienna. In it he reviewed the Hansemann-Boveri hypothesis and contemporary ideas on the origin of cancer.…”

Section: A Lively Echomentioning

confidence: 99%

Reappraisal of the Hansemann–Boveri hypothesis on the origin of tumors

Hardy

Zacharias

2005

Cell Biology International

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Cancer is now known to be a genetic disease. In tumor development, cell nuclei undergo mutations, which can result in cytologically visible chromosome aberrations. The aneuploid errors may involve amplification or deletion of whole chromosomes or segments thereof. David Hansemann [1858-1920] and Theodor Boveri [1862-1915] were major contributors to early debates on the relationship between chromosomal defects, tumorigenesis and malignancies. In 1890, Hansemann observed asymmetrical nuclear divisions in human epithelial cancers. In these abnormal, but bipolar, divisions, a fraction of the chromosomes fails to segregate properly. Hansemann carefully documented the occurrence of asymmetric divisions in a wide variety of tumors. However, he remained a lifelong skeptic with regard to whether such events could be considered the underlying cause of tumors. Almost a quarter of a century after Hansemann's initial observations, Boveri considered the origin of tumors based on his earlier recognition of the functional specificity of each chromosome. He also explicitly drew on Hansemann's observations in proposing a model for tumorigenesis. Its central tenet was that a tumor typically originates from a single cell that has inherited a defined, but incorrectly combined, set of chromosomes. The rare occurrence of a pluripolar spindle represented Boveri's paradigm for a type of abnormal mitosis that can produce a host of random chromosomal combinations. He suggested that some of these combinations will induce tumorous transformation, and will inevitably arise occasionally. Since pluripolar and unbalanced bipolar divisions fail to distribute the hereditary chromatic material correctly, both of these mechanisms can give rise to tumor progenitors.

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Section: A Lively Echomentioning

confidence: 99%

Reappraisal of the Hansemann–Boveri hypothesis on the origin of tumors

Hardy

Zacharias

2005

Cell Biology International

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“…The disturbance of mitotic and meiotic divisions may also be caused by a comparatively large number of factors. In the recent literature the list of agencies causing irregularities of the nuclear divisions has been steadily increasing (Politzer, 1934;Sax, 1937). Notwithstanding the very different nature of these agencies (temperature, chemicals, X-ray treatment, vital stains, etc.)…”

Section: Gms Per Litermentioning

confidence: 99%

Effects of Calcium Deficiency Upon the Roots of Pisum Sativum

Sorokin

Sommer

1940

American J of Botany

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Solution without calciumFe (as FeS04) was added as needed by the plants.plant. The plants were g-rown in solutions of highly purified salts. A detailed description of the methods employed, as well as of the purification of the salts is given elsewhere (Sommer and Sorokin, 1928). All water was redistilled from a pyrex glass still. The following solutions were employed in this series of experiments:Calcium sulfate in amounts to give calcium concentrations of 0.06, 0.125 and 0.25 parts per million was added to cultures on which the studv of the effects of small amounts of calcium was to be made.The plants, each treatment in triplicate, were grown in 2-liter pyrex beakers. In a preliminary experiment two out of twenty beakers were discarded because plants grown in them without the addition of calcium consistently produced more root growth than plants grown in the other beakers under the same conditions. Specially constructed fitted wooden covers were coated with paraffin and the seedlings, four to each beaker, were set out through cotton plug-ged openings. The beakers were set in galvanized iron tanks filled with water, which came to within about an inch of the top of the beakers. Water

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“…Various authors (Politzer 1934;Stone 1933;M ather 1934) have described phenomena which present a certain similarity to those described above. Stone and M ather found a certain number of metaphases and anaphases which showed a great deal of " fragm entation" .…”

Section: -Discussionmentioning

confidence: 53%

“…I t is clear th a t this hypothesis is not applicable to the three species of O rthoptera I have described here, since in none of them is there any appreciable am ount of terminalization. Politzer (1934) has described pycnotic metaphases and anaphases which result from irradiation. I t is not clear w hat relation exists between pycnosis and the phenomenon of chromosome disintegration; possibly they are only quantitatively different, b u t it seems more likely th a t they are really distinct phenomena.…”

Section: -Discussionmentioning

confidence: 99%

The effect of X-rays on the first meiotic division in three species of orthoptera

White

1937

Proc. R. Soc. Lond. B

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Although several papers have been published which deal with the cytological effects of irradiation, the whole subject is still in the preliminary or exploratory stage. It is clear that a complex sequence of biochemical phenomena result from the irradiation of a tissue, and that these may produce morphological changes in the chromosomes and other constituents of the cell. Generalizations based on the genetical results obtained by irradiating Drosophila sperm are dangerous, since the male gamete is a highly peculiar cell with practically no cytoplasm or nuclear sap. The few papers which have dealt with the effects of X-rays on the meiotic divisions (Helwig 1933; Mather 1934; Stone 1933; Huskins and Hunter 1935; Riley 1936), although interesting, are really only preliminary studies. In a previous paper the author (White 1935) dealt with the effects of irradiation on the spermatogonial (mitotic) divisions of the migratory locust. This, the second paper, deals with certain effects observed at the first meiotic division in three other species of Orthoptera, Mecostethus grossus L., Metrioptera brachyptera L. and Stauroderus ( Chorthippus bicolor Charp. Future papers will deal in further detail with other phenomena resulting from irradiation, the effects of different dosages, etc.

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Pathologie Der Mitose

Cited by 60 publications

References 0 publications

Reappraisal of the Hansemann–Boveri hypothesis on the origin of tumors

Reappraisal of the Hansemann–Boveri hypothesis on the origin of tumors

Effects of Calcium Deficiency Upon the Roots of Pisum Sativum

The effect of X-rays on the first meiotic division in three species of orthoptera

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