Month: September 2022

Darwin comes to town: how cities are creating new species https://www.theguardian.com/cities/2018/jul/23/darwin-comes-to-town-how-cities-are-creating-new-species?CMP=Share_iOSApp_Other View in LinkedIn

CLEAR DISTINCTION. "All normal cells both in vitro and in vivo are mortal and that abnormal cancer cells both in vitro and in vivo are immortal." Cancerous cells are heteroploid while normal cells are diploid. http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

PROPERTIES OF MORTAL CELLS #1. "If derived from human embryos, cell strains undergo about 50 population doublings. The potential cell yield from 50 population doublings is about 20 million metric tons." http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

PROPERTIES OF MORTAL CELLS #2. "Human diploid cells undergo a number of population doublings inversely proportional to donor age. This suggested to us that the finite replicative capacity of cultured normal cells is an expression of aging at the cell level. This notion received considerable experimental support in subsequent years and became the basis for the field of cell aging." http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

PROPERTIES OF MORTAL CELLS #3. "If derived from normal tissue, cell strains have the diploid karyotype and unlike immortal cell lines, normal cell strains are incapable of replication in suspension culture. This property is now called anchorage dependence." http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

PROPERTIES OF MORTAL CELLS #4. "Human cell strains will not produce tumors when inoculated into the hamster cheek pouch or even when directly inoculated into terminal human cancer patients." http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

PROPERTIES OF MORTAL CELLS #5. "Human diploid cell strains can be cryogenically preserved. When, for example, our first widely distributed normal human diploid cell strain WI-38, developed in 1962, is preserved at a particular doubling level and then reconstituted, the number of doublings remaining is equivalent to 50 minus the number of doublings spent prior to preservation." http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

CRYOGENIC PRESERVATION. "The cells have an extraordinary memory and "remember" at what doubling level the were preserved even after 35 years of continuous storage in liquid nitrogen. WI-38 has been cryogenically preserved longer than any other normal human or animal cell population." (There is a very interesting story behind WI-38 cells if you care to look it up). http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

THE IMMORTALITY CONDITION. "If all cell types were continually renewed without loss of function or capacity for self-renewal, organs composed of such cells would be expected to function normally indefinitely. Their host would live forever." http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

THE MORTALITY REALITY. "As Weismann opined, renewal cell populations do not occur in most tissues, and when the do, cell proliferation is not indefinite. In vitro experiments yield similar results. Serially cultured normal cells are mortal and reveal age changes before they die." (Normal cells). http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn