Ngokuvamile sicabanga ngamalensi okuxhumana njengamadivayisi wezokwelapha alula ukulungisa izinkinga zethu zombono. Eqinisweni, ama-lens axhumene nawo ajwayelekile futhi asakazeke emhlabeni jikelele ukuthi umphakathi ubhekana nabo njengempahla kunokuba amadivayisi wezokwelapha. Kodwa namuhla, amalense oxhumana nawo asetshenziselwa ukwelapha izinkinga zamehlo ezinzima zezokwelapha. Sekuyisikhathi eside odokotela bezinyosi basebenzise "ama-lens wokuxhumana ama-bandia" ukuze baphathe izinkinga zamehlo njenge-filamentary keratitis, izimo eziphuthumayo ze-epithelial kanye nokukhubazeka okune-corneal nama-abrasions.
Muva nje, amadivaysi oxhumana ne-lens afana ne-Prokera aletha izakhiwo zokuphulukisa kwi-cornea nge-amniotic tissue. Amathissi amniotic athathwa kusuka e-placenta futhi asetshenziselwa ukwakha uhlobo lwe-lens yokubopha ukusiza ekuphulukiseni i-cornea. Kodwa-ke, abacwaningi sebeqalile ukusebenzisa amalensi okuxhumana ukuze basize isiko namaseli athile anempilo ezigulini. Lezi lens ezinama-cell e-stem zisetshenziselwa ukuphatha izifo eziphezulu zamehlo.
Yiziphi Amaseli Okuqala?
Ama-stem cells amangqamuzana emzimbeni wethu angasebenzi futhi alinde ukuba abe ngamaseli akhethekile ukwenza imisebenzi ethile. Kunezinhlobo ezimbili zama cell stem: amangqamuzana e-embryonic stem namaseli omdala asempumalanga (ngezinye izikhathi abizwa ngokuthi amangqamuzana angama-somatic stem.) Lawa maseli angakwazi ukuhlukanisa izinhlobo ezahlukene zeseli njengezikhumba, iso, isisindo nama-muscle amaseli. Ama-stem omdala amangqamuzana atholakala ezindaweni eziningi emzimbeni futhi ahlale elele kuze kube yilapho isifo noma ukulimala kwezicubu kwenzeka.
Bese behlukanisa izinhlobo ezahlukene zeseli ukuze bathathe isikhundla sesishukela. Bacatshangwa ukuthi bakwazi ukwahlukanisa futhi baziphindaphinda ngokwabo kuze kube phakade.
Ngokuphambene, amangqamuzana e-embryonic stem avela kuphela kumbungu wesintu omdala ongu-4-5. Lapho isetshenziselwa ucwaningo, zakhiwa ebhokisatri futhi azitholakali ngqo emphakathini.
Amaseli e-embryonic stem akwazi ukwahlukanisa kunoma yiziphi izicubu emzimbeni womuntu, kanti amangqamuzana omuntu omdala anqunyelwe kulokho angakhula khona. Ukuphikisana kukhona okuzungeze ukusetshenziswa kwamaseli ase-stem ekunakekelweni kwezokwelapha, kodwa ngokuvamile lokhu kuhilela amangqamuzana e-stry embryonic, njengoba amangqamuzana omdala omdala angatholakala ngokuqondile emzimbeni futhi angabandakanyi imibungu yabantu.
Isebenza kanjani?
Elula futhi engabizi, inqubo ayiyona ingavamile futhi ayidingi ukusetshenziswa kwezicubu zomuntu wangaphandle noma imikhiqizo yezilwane. Inani elincanyana kakhulu lezincubu ezisuka kweso lesiguli livunwa ama-stem cells. Zibekwe kuma-lens wokuxhumana aphethwe yi-FDA-avunyelwe. Lawa maseli akhuliswa futhi agculwe ku-serum yesiguli.
Ama-stem amangqamuzana akhula ngokushesha futhi afaka ubuso bomlingo wokuxhumana emayelana namasonto amabili kuya kwamathathu. Uma i-lens isethelwe esweni lesiguli, amangqamuzana ayafudukela ku-cornea ngenqubo ososayensi abangayiqondi. Amaseli aqala ukukhula futhi adale ungqimba oluthile lwamaseli angaba nethemba lokubuyisela umbono futhi alungise ukuphazamiseka kwamehlo. I-lens ingaba yi-biodegradable. Awekho ama-sutures futhi akukho mishini ewudingayo edingekayo ukuqedela inqubo.
Izindlela zokwelashwa zangaphambilini zisebenzisa ama-stem cells abandakanyekayo ukuhlanganisa ama-cell esweni esebenzisa izicubu zomuntu ezinikelwe.
Noma kunjalo, izinga lokuphumelela lihluka futhi likwazi ukuhluleka ngemva kweminyaka embalwa njengoba iso lokuphulukisa lingakwazi ukugcina amangqamuzana amancane. Ukusebenzisa amaseli we-stem wesiguli esikhundleni samaseli we-stem omnikeli angase aqede ukukhathazeka ngokulahlwa. Lokhu kungase kusize kakhulu ezimweni lapho amabhange amancane ahlala khona aphelile noma engatholakali, noma ezindaweni ezingenawo amabhange amancane okufakelwa. Ama-lensi amasha okuxhumana angenawo amakhemikhali afaka amapokhethi angene endlini futhi avikele amaseli asemathunjini.
Yini Ama-Cell Stem Contact Amalensi Okuphathwayo?
Amalensi oxhumana nawo agcwele ama-stem cell ahloswe ngokuyinhloko ekwelapheni izinkinga ze- cornea , isakhiwo esicacile se-dome-like on the front of the eye.
Ukulimala kwe-corneal ngokuvamile kuthinta uhlaka olungaphandle lwama-cornea, amangqamuzana e-epithelial, futhi kungabangelwa izibazi kusukela ekuhlinzeni, izibazi ezibulalayo, izifo, izifo ezingenalutho nokuvuvukala kwamehlo abomile kakhulu. Izimpawu zesifo se-corneal zifaka ubuhlungu, ukubhuka, ukushintshashintsha komqondo nokuzwela ukukhanya.
Isimo esivame kakhulu esiphathwa nge-stem cell i-lens esakhulile yileli lensimbi ye-limbal stem cell. Ukuntuleka kwe-Limbal stem cell kungabangelwa ukuhlukunyezwa okuvela emlilweni wokushisa, ukushisa okushisayo kanye nesimo sezakhi zofuzo okuthiwa i-congenital aniridia. Ngokuthakazelisayo, odokotela babona ukwanda kweziguli ezine-limbal stem cell deficiency ezivela kwezinye izinto ezifana nokugqoka kwesikhatsi eside sokuxhumana, i-ocular surface, njenge- eye ehlala njalo, ukuhlinzwa kwe-cataract kanye nezinhlinzeko ezithile ze-glaucoma ne-pterygium.
> Umthombo:
> Di Girolamo, uNick. Ikhono Lokuxhumana Lens Lens for Extension and Transplantation of Autologous Epithelial Progenitors for Ukuvuselelwa Kwama-Ocular Surface. Ukufakelwa kwezitshalo , 2009.