Akụkọ ihe mere eme nke okike nke echiche Hayflick
Leonard Hayflick (amuru May 20, 1928 na Philadelphia), prọfesọ nke anatomy na Mahadum California dị na San Francisco, mepụtara echiche ya mgbe ọ na-arụ ọrụ na Wistar Institute na Philadelphia, Pennsylvania, na 1965. Frank MacFarlane Burnet kpọrọ echiche a mgbe Hayflick nọ na ya. akwụkwọ ya akpọrọ Internal Mutagenesis, nke e bipụtara na 1974. Echiche nke oke Hayflick nyeere ndị ọkà mmụta sayensị aka inyocha mmetụta nke ịka nká cell na ahụ mmadụ, mmepe cell site na ogbo embrayo ruo ọnwụ, gụnyere mmetụta nke mbelata ogologo nke nsọtụ chromosomes a na-akpọ. telomeres.
N'afọ 1961, Hayflick malitere ịrụ ọrụ na Wistar Institute, bụ ebe ọ chọpụtara na mkpụrụ ndụ mmadụ anaghị ekewa ruo mgbe ebighị ebi. Hayflick na Paul Moorehead kọwara ihe omume a n'ime otu akwụkwọ akụkọ akpọrọ Serial Cultivation of Human Diploid Cell Strains. Ọrụ Hayflick na Wistar Institute bu n'obi inye ihe ngwọta na-edozi ahụ maka ndị ọkà mmụta sayensị mere nnwale na ụlọ ọrụ ahụ, mana n'otu oge ahụ Hayflick na-etinye aka na nyocha nke ya banyere mmetụta nje na sel. N'afọ 1965, Hayflick kọwapụtara echiche nke oke Hayflick n'otu akwụkwọ akụkọ akpọrọ "Limited Lifespan of Human Diploid Cell Strains in the Artificial Environment".
Hayflick bịara na nkwubi okwu na cell nwere ike imezu mitosis, ya bụ, usoro ọmụmụ site na nkewa, naanị ugboro iri anọ na iri isii, mgbe nke ahụ gasịrị, ọnwụ na-apụta. Nkwubi okwu a metụtara ụdị sel niile, ma ndị okenye ma ọ bụ sel nje. Hayflick weputara echiche nke opekempe nwere ike imepụtaghachi cell na ịka nká yana, ya mere, na usoro ịka nká nke ahụ mmadụ.
Na 1974, Hayflick mebere National Institute on Aging na Bethesda, Maryland.
Ụlọ ọrụ a bụ ngalaba nke US National Institutes of Health. Na 1982, Hayflick ghọkwara osote onye isi oche nke American Society for Gerontology, hiwere na 1945 na New York. N'ikpeazụ, Hayflick rụrụ ọrụ ime ka echiche ya gbasaa ma gbaghaa ozizi Carrel nke anwụghị anwụ.
Nkwughachi nke echiche Carrel
Alexis Carrel, bụ dọkịta na-awa France nke na-arụ ọrụ na anụ ahụ anụ ọkụkọ na mmalite narị afọ nke iri abụọ, kwenyere na mkpụrụ ndụ nwere ike ịmụpụta ruo mgbe ebighị ebi site n'ikewa. Carrel kwuru na ya nwere ike nweta nkewa nke mkpụrụ ndụ obi ọkụkọ na nri nri - usoro a gara n'ihu ruo ihe karịrị afọ iri abụọ. Nnwale ya na anụ ahụ anụ ọkụkọ mere ka ozizi nke nkewa cell na-adịghị agwụ agwụ sikwuo ike. Ndị ọkà mmụta sayensị agbalịwo ugboro ugboro imeghachi ọrụ Carrel, ma nyocha ha ekwenyeghị na "nchọpụta" nke Carrel.
Nkatọ nke ozizi Hayflick
N'afọ ndị 1990, ụfọdụ ndị ọkà mmụta sayensị, dị ka Harry Rubin na Mahadum California dị na Berkeley, kwuru na njedebe Hayflick na-emetụta naanị mkpụrụ ndụ mebiri emebi. Rubin tụrụ aro na mmebi cell nwere ike ịkpata n'ihi mkpụrụ ndụ ndị dị na gburugburu ebe dị iche na ebe mbụ ha dị na ahụ, ma ọ bụ ndị ọkà mmụta sayensị na-ekpughe sel ndị dị na ụlọ nyocha.
Nyocha ọzọ banyere ihe mere ịka nká
N'agbanyeghị nkatọ, ndị ọkà mmụta sayensị ndị ọzọ ejiriwo echiche Hayflick mee ihe dị ka ihe ndabere maka nyocha ọzọ gbasara ihe gbasara ịka nká cellular, karịsịa telomeres, nke bụ akụkụ njedebe nke chromosomes. Telomeres na-echebe chromosomes ma belata mmụgharị na DNA. N'afọ 1973, ọkà mmụta sayensị Russia bụ A. Olovnikov tinyere ozizi Hayflick nke ọnwụ cell na ọmụmụ ya banyere njedebe nke chromosomes na-adịghị amụba onwe ha n'oge mitosis. Dị ka Olovnikov si kwuo, usoro nkewa sel na-akwụsị ozugbo cell ahụ enwekwaghị ike imepụtaghachi nsọtụ nke chromosomes ya.
Otu afọ ka e mesịrị, na 1974, Burnet kpọrọ Hayflick theory the Hayflick limit, na-eji aha a n'akwụkwọ ya, Internal Mutagenesis. N'ime obi ọrụ Burnet bụ echiche na ịka nká bụ ihe dị mkpa dị n'ime mkpụrụ ndụ nke ụdị ndụ dị iche iche, yana na ọrụ ha dị mkpa kwekọrọ na tiori a maara dị ka njedebe Hayflick, nke na-ewepụta oge ọnwụ nke akụkụ ahụ.
Elizabeth Blackburn nke Mahadum San Francisco na onye ọrụ ibe ya Jack Szostak nke Harvard Medical School na Boston, Massachusetts, tụgharịrị na tiori Hayflick limit na ọmụmụ ha banyere nhazi nke telomeres na 1982 mgbe ha nwere ihe ịga nke ọma n'ịkpọchi na ikewapụ telomeres.
N'afọ 1989, Greider na Blackburn mere nzọụkwụ ọzọ n'ịmụ ihe gbasara ịka nká cell site na ịchọta enzyme a na-akpọ telomerase (enzyme sitere na otu transferases nke na-achịkwa nha, ọnụọgụ na nucleotide mejupụtara chromosome telomeres). Greider na Blackburn chọpụtara na ọnụnọ telomerase na-enyere mkpụrụ ndụ anụ ahụ aka izere ọnwụ e mere atụmatụ.
N'afọ 2009, Blackburn, D. Szostak na K. Greider nwetara Nrite Nobel na Physiology ma ọ bụ ọgwụ na okwu "maka nchọpụta ha chọpụtara usoro nchebe nke chromosomes site na telomeres na enzyme telomerase." Nchọpụta ha dabere na oke Hayflick.