Uphononongo lwamawele akutsha nje lubonise iindlela ezintsha zokuhlaziya intliziyo eyonakeleyo
Ukungaphumeleli kwentliziyo kuchaphazela ubuncinci abantu abazizigidi ezingama-26 kwihlabathi liphela kwaye kunoxanduva lokufa okuninzi. Ngenxa yokunyuka kwabantu abalupheleyo, ukunyamekela intliziyo isiba yimfuno ekhokelela ekunyukeni kwenkcitho. Kubekho inkqubela phambili ebonakalayo kunyango lonyango lwe intliziyo kwaye amanyathelo amaninzi okuthintela ayathathwa, nangona kunjalo, ukufa kunye nokugula kusephezulu kakhulu. Zimbalwa kakhulu iindlela zoNyango olukhoyo kwaye ubukhulu becala luxhomekeke kuqhaqho-fakelo lwentliziyo kwizigulana ezikwinqanaba lokugqibela kwaye ziqhubela phambili kukusilela kwentliziyo ngokupheleleyo.
Umzimba wethu unawo amandla angaqhelekanga okuziphilisa, umzekelo isibindi sinokuphinda sihlaziyeke xa sonakele, ulusu lwethu naso ixesha elininzi kwaye intso enye inokuthatha indawo yokusebenza kabini. Ngelishwa, oku akuyonyani kuninzi lwamalungu ethu abalulekileyo - kubandakanywa nentliziyo. Xa intliziyo yomntu yonakele - ebangelwa sisifo okanye ukwenzakala - umonakalo ungunaphakade. Umzekelo, emva kokuhlaselwa yintliziyo, izigidi okanye iibhiliyoni zeeseli zezihlunu zentliziyo zinokulahleka ngonaphakade. Le lahleko iyenza buthathaka intliziyo ngokuthe ngcembe kwaye ikhokelele kwiimeko ezimandundu ezifana nokusilela kwentliziyo, okanye amanxeba entliziyweni anokubonakalisa ukufa. Ukungaphumeleli kwentliziyo ngokuqhelekileyo kubangela ukuba i-cardiomyocytes (uhlobo lweeseli) lunqongophele. Ngokungafaniyo ne-newts kunye ne-salamanders, abantu abadala abanakukwazi ukuphinda baphinde baphinde bakhulise amalungu onakeleyo njengentliziyo. Kwimbumba yomntu okanye xa usana lukhula esibelekweni. intliziyo iiseli ziyahlukana kwaye ziphindaphindeke nto leyo enceda intliziyo ukuba ikhule kwaye ikhule iinyanga ezilithoba. Kodwa izilwanyana ezanyisayo ezibandakanya abantu azinawo amandla okuhlaziya intliziyo njengoko ziphulukana nobu buchule emva koko kwaye ngokupheleleyo emva kweveki yokuzalwa. Iiseli zezihlunu zentliziyo zilahlekelwa amandla azo okwahlula kwaye ziphindaphindeke kwaye ngenxa yoko azikwazi ukuphinda zikhule. Oku kuyinyani nakwezinye iiseli zomntu - ingqondo, umqolo njl Nangona esi ikwasisizathu sokuba kungabikho thumba lentliziyo - amathumba abangelwa kukukhula okungalawulekiyo kweeseli. Ukuba, nangona kunjalo, kunokwenziwa ukuba ezi seli ziphinde zihlukane kwakhona, oku kunokukhokelela "ekuhlaziyweni" kwenani lezicubu kunye nokunceda ukulungisa ilungu.
Inye kuphela inketho apho nabani na xa ephethwe buthathaka okanye intliziyo eyonakele okanye isifo sentliziyo kukufumana uqhaqho-fakelo lwentliziyo. Oku kunemiba emininzi echaphazela ngokubanzi uqhaqho-fakelo ekubeni yinyani kwizigulane ezininzi. Okokuqala, intliziyo enikelwe “ngumnikeli” kufuneka ibe yintliziyo ephilileyo phambi kokuba lowo unikeleyo asweleke, nto leyo ethetha ukuba intliziyo ifuna ukuvunwa kubantu abatsha abasweleke ngenxa yokugula okanye ukwenzakala kwaye ezi meko azibachaphazeli. intliziyo nangayiphi na indlela. Isigulana esilindelekileyo kufuneka sihambelane nentliziyo yomxhasi ukuze sifumane uqhaqho-fakelo. Oku kuguqulela ekubeni kukulinda ixesha elide. Njengenye indlela enokwenzeka, ukubanakho ukwenza isihlunu esitsha entliziyweni ngokuhlukana kweeseli kunokunika ithemba kwizigidi ezinentliziyo eyonakeleyo. Iinkqubo ezininzi ziye zazanywa kwaye zavavanywa luluntu lwezenzululwazi, nangona kunjalo, iziphumo ukuza kuthi ga ngoku azisebenzi.
Kwisifundo esitsha esishicilelwe kwi Iseli, abaphandi kwiYunivesithi yaseCalifornia, eSan Francisco, eU.SA okokuqala ngqa baphuhlise indlela esebenzayo kunye nezinzile kwiimodeli zezilwanyana ukwenza iiseli zentliziyo yabantu abadala (i-cardiomyocytes) zahlula kwaye ngaloo ndlela ziyakwazi ukulungisa inxalenye eyonakalisiweyo yentliziyo.1. Ababhali bachonge iijini ezine ezibandakanyekayo kulwahlulo lweeseli (ziiseli eziziphindaphinda ngokwazo). Xa ezi zakhi zofuzo zidityaniswe nejene ezibangela ukuba i-cardiomyocyte evuthiweyo iphinde ingene kumjikelo weseli, babona ukuba iiseli ziyahlula kwaye zivelise kwakhona. Ngoko ke, xa umsebenzi wezi mfuza zine ezibalulekileyo waphuculwa, i intliziyo izicubu zibonise ukuvuselelwa. Emva kokungaphumeleli kwentliziyo kwisigulane, le ndibaniselwano iphucula umsebenzi wentliziyo. I-Cardiomyocytes ibonise i-15-20 yepesenti yecandelo kwisifundo esikhoyo (xa kuthelekiswa nepesenti ye-1 kwizifundo zangaphambili) ukuqinisa ukuthembeka kunye nokusebenza kakuhle kwesi sifundo. Olu phononongo lunokwandiswa ngokobuchwephesha tp amanye amalungu kuba ezi genes zine ziyinto eqhelekileyo. Lo ngumsebenzi ofanelekileyo kakhulu kuba naluphi na uphando kwi intliziyo okokuqala intsonkothe kakhulu kwaye okwesibini ukuhanjiswa kofuzo kufuneka kwenziwe ngononophelo ukuze kungabangeli naziphi na iithumba emzimbeni. Lo msebenzi unokujika ube yindlela enamandla kakhulu yokuhlaziya intliziyo kunye namanye amalungu omzimba.
Olunye uphando olwenziwa yiStem Cell Institute, kwiYunivesithi yaseCambridge, e-UK, luphuhlise indlela entsha yokulungisa intliziyo izicubu ezinokuthi umxhasi angafuneki kwaphela2. Baye basebenzisa iiseli ze-stem ukukhulisa amabala aphilayo "emisipha yentliziyo" kwibhubhoratri eyi-2.5 yeesentimitha zesikwere kuphela kodwa zikhangeleka njengesixhobo esinamandla sokunyanga izigulane ezinesifo senhliziyo. Ezi patches zinethemba eliqaqambileyo lokufunyanwa ngokwendalo kwisigulana intliziyo okt sisihlunu “esisebenza ngokupheleleyo” esibetha kwaye sifinyeze kanye njengesihlunu sentliziyo esiqhelekileyo. Indlela yangaphambili yokutofa iiseli ze-stem emzimbeni ukulungisa intliziyo ayiphumelelanga kuba iiseli ze-stem azizange zihlale ngaphakathi. intliziyo isihlunu kodwa endaweni yoko yalahleka egazini. Isiqwenga sangoku "siphila" kunye "nokubetha" kwezicubu zentliziyo ezinokudityaniswa nelungu (kule meko intliziyo) yaye ngaloo ndlela nawuphi na umonakalo unokulungiswa. Amabala anjalo anokukhuliswa xa kukho imfuneko yesigulana. Oku kuya kudlula imfuneko yokulinda umnikezeli ohambelanayo. Ezi patshi zinokukhuliswa kusetyenziswa i intliziyo iiseli zesigulana zisusa iingozi ezibandakanyekayo kuqhaqho-fakelo lwamalungu. Ukulinganisa isiziba kwi-a intliziyo eyonakele yinkqubo ehlaselayo kwaye ifuna iimpembelelo zombane ezichanekileyo zokwenza intliziyo ibetha idityaniswe kakuhle kunye nepetshi. Kodwa imingcipheko ebandakanyekayo kolu hlobo lwenkqubo ingcono ukuba uqhaqho-fakelo lwentliziyo lulonke oluhlasela kakhulu. Iqela lilungiselela ulingo lwezilwanyana kunye nolingo lwezonyango phakathi kweminyaka emi-5 ngaphambi kokuba oku kusetyenziswe ngokubanzi intliziyo izigulane.
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{Unokufunda iphepha lokuqala lophando ngokunqakraza ikhonkco le-DOI elinikwe ngezantsi kuluhlu lwemithombo ecatshulweyo (s)}
Umthombo (s)
1. U-Mohamed et al. 2018,. UkuLawulwa koMjikelo weCell ukukhuthaza ukuKhuliswa kweCardiomyocyte yabantu abadala kunye nokuvuselelwa kweCardiac. iseli. https://doi.org/10.1016/j.cell.2018.02.014
2. IYunivesithi yaseCambridge 2018. Ukupakisha intliziyo eyaphukileyo. http://www.cam.ac.uk/research/features/patching-up-a-broken-heart. [Ifikeleleke ngoMeyi 1 2018]
