Taariikhda abuurista aragtida Hayflick
Leonard Hayflick (wuxuu ku dhashay May 20, 1928 Philadelphia), borofisar ku takhasusay anatomy ee Jaamacadda California ee San Francisco, wuxuu horumariyay aragtidiisa isagoo ka shaqeynayay Machadka Wistar ee Philadelphia, Pennsylvania, 1965. Frank MacFarlane Burnet wuxuu aragtidan u magacaabay Hayflick Buugiisa oo cinwaankiisu yahay Internal Mutagenesis, oo la daabacay 1974. Fikradda xaddidka Hayflick waxay ka caawisay saynisyahannada inay daraasad ku sameeyaan saamaynta gabowga unugga ee jidhka bini'aadamka, horumarka unugyada laga bilaabo heerka uur-jiifka ilaa dhimashada, oo ay ku jirto saameynta gaaban ee dhererka cidhifyada koromosoomyada ee loo yaqaan telomeres
Sannadkii 1961kii, Hayflick waxa uu ka shaqo bilaabay machadka Wistar, halkaas oo uu ku arkay isaga oo eegaya in unugyada bini’aadamku aanay u qaybsamin si aan xad lahayn. Hayflick iyo Paul Moorehead waxay ku sifeeyeen dhacdadan buug keli ah oo cinwaan looga dhigay Beerista Taxanaha ah ee Cadaadiska Unugyada Diploid ee Aadanaha. Hawsha Hayflick ee machadka Wistar waxa ay ugu tala gashay in ay siiso xal nafaqeeyayaal saynisyahano ah oo tijaabo ku sameeyay machadka, balse isla wakhtigaas Hayflick waxa uu ku hawlanaa cilmi baadhis u gaar ah oo ku saabsan saamaynta fayrasku ku leeyahay unugyada. Sannadkii 1965kii, Hayflick waxa uu ku faahfaahiyey fikradda xaddidka Hayflick buug keli ah oo cinwaankiisu yahay “Cilmi-nololeed xaddidan ee Unugyada Diploid-ka Aadanaha ee Deegaanka Macmalka ah”.
Hayflick wuxuu soo gabagabeeyay in unuggu awood u leeyahay inuu dhammaystiro mitosis, ie, habka taranka iyada oo loo marayo qaybinta, kaliya afartan ilaa lixdan jeer, ka dib dhimashadu waxay dhacdaa. Gabagabadani waxay qusaysay dhammaan noocyada kala duwan ee unugyada, hadday yihiin unugyo waaweyn iyo hadday yihiin jeermis. Hayflick wuxuu soo bandhigay mala-awaal iyadoo loo eegayo awoodda wax-ku-noqoshada unugga ee ugu yar ay la xiriirto gabowga iyo, sidaas awgeed, habka gabowga ee jidhka bini'aadamka.
Sannadkii 1974-kii, Hayflick waxa uu aasaasay Machadka Qaranka ee Gabowga ee Bethesda, Maryland.
Machadkani waa laan ka mid ah machadyada caafimaadka qaranka ee Maraykanka. Sannadkii 1982kii, Hayflick waxa kale oo uu noqday guddoomiye ku xigeenka Ururka Maraykanka ee Gerontology, oo la aasaasay 1945 magaalada New York. Intaa ka dib, Hayflick waxa uu ka shaqeeyay in uu faafiyo aragtidiisa oo uu beeniyo aragtida Carrel ee dhimasha-la'aanta gacanta.
Diidmada aragtida Carrel
Alexis Carrel, oo ah dhakhtar Faransiis ah oo la shaqeeyay unugyada wadnaha digaaga horraantii qarnigii labaatanaad, ayaa rumaysnaa in unugyadu ay si aan xad lahayn u taran karaan iyagoo qaybinaya. Carrel wuxuu ku andacooday in uu awooday in uu gaaro kala qaybinta unugyada wadnaha digaaga ee dhexdhexaad nafaqo - habkani wuxuu sii socday in ka badan labaatan sano. Tijaabooyinka uu ku sameeyay unugyada wadnaha digaaga ayaa xoojiyay aragtida qaybinta unugyada aan dhamaadka lahayn. Saynis yahanadu waxay marar badan isku dayeen inay ku celiyaan shaqada Carrel, laakiin tijaabadooda ma aysan xaqiijin "helitaanka" Carrel.
Dhaleecaynta aragtida Hayflick
Sagaashameeyadii, saynisyahano, sida Harry Rubin oo ka tirsan Jaamacadda California ee Berkeley, ayaa sheegay in xadka Hayflick uu quseeyo oo keliya unugyada dhaawacan. Rubin waxa uu soo jeediyay in dhaawaca unuggu uu sababi karo unugyadu oo ku sugan deegaan ka duwan deegaanka ay asal ahaan ka soo jeedaan ee jidhka, ama ay saynisyahannadu soo bandhigaan unugyada shaybaadhka.
Baaritaan dheeraad ah oo lagu sameeyo ifafaalaha gabowga
In kasta oo dhaleeceyntu jirto, saynisyahano kale ayaa u adeegsaday aragtida Hayflick oo saldhig u ah cilmi baaris dheeraad ah oo lagu sameeyo ifafaalaha gabowga gacanta, gaar ahaan telomeres, kuwaas oo ah qaybaha dhamaadka koromosoomyada. Telomeres waxay ilaaliyaan koromosoomyada waxayna yareeyaan isbeddellada DNA-da. Sannadkii 1973-kii, saynis yahankii Ruushka ahaa ee A. Olovnikov waxa uu cilmi-baadhistiisa ku dabaqay aragtida Hayflick ee dhimashada unugga ee dhammaadka koromosoomyada kuwaas oo aan dib isu soo saarin inta lagu jiro mitosis. Sida laga soo xigtay Olovnikov, habka qaybinta unuggu wuxuu dhammaanayaa isla marka unugu aanu dib u soo saari karin dhamaadka koromosoomyadiisa.
Sannad ka dib, 1974-kii, Burnet waxa uu ugu yeedhay aragtida Hayflick xadka Hayflick, isaga oo magacan ku dhex isticmaalaya warqadiisa, Mutagenesis Internal. Xuddunta shaqada Burnet waxa ay ahayd malo ah in gabowga uu yahay arrin ka dhex jirta unugyada noocyada kala duwan ee nolosha, iyo in hawshooda muhiimka ahi ay la mid tahay aragtida loo yaqaan xadka Hayflick, taas oo dejisa wakhtiga dhimashada noolaha.
Elizabeth Blackburn oo ka tirsan Jaamacadda San Francisco iyo saaxiibkeed Jack Szostak oo ka tirsan Dugsiga Caafimaadka Harvard ee Boston, Massachusetts, waxay u jeesteen aragtida xaddidaadda Hayflick ee daraasaddooda qaabdhismeedka telomeres 1982 markii ay ku guulaysteen inay xidhaan oo go'doomiyaan telomeres.
1989kii, Greider iyo Blackburn waxay qaadeen tillaabadii xigtay ee daraasadda ifafaalaha gabowga unugga iyagoo helay enzyme la yiraahdo telomerase (ensaymes ka tirsan kooxda wareejinta oo koontaroolaysa cabbirka, tirada iyo halabuurka nucleotide ee koromosoomyada telomeres). Greider iyo Blackburn waxay ogaadeen in joogitaanka telomerase ay ka caawiso unugyada jidhku inay iska ilaaliyaan dhimashada qorshaysan.
Sannadkii 2009, Blackburn, D. Szostak iyo K. Greider waxay heleen abaalmarinta Nobel Prize ee Physiology ama Medicine iyadoo ereyga "helitaanka hababka ilaalinta koromosoomyada ee telomeres iyo telomerase enzyme." Cilmi-baadhistoodu waxay ku salaysnayd xadka Hayflick.