Ukwahluka kwesifo seCreutzfeldt-Jakob (vCJD), yafunyanwa okokuqala ngo-1996 e-United Kingdom, i-bovine spongiform encephalopathy (BSE okanye isifo 'semad cow') kwaye Isifo se-Zombie deer okanye isifo esingapheliyo sokuchitha (CWD) ezisematheni ngoku zinento enye efanayo – izinto ezibangela izifo ezithathu aziyobhaktheriya okanye iintsholongwane kodwa iiprotheyini 'ezikhubazekileyo' ezibizwa ngokuba 'yi-prions'.
Iiprions zisuleleka kakhulu kwaye zijongene nezifo ezibulalayo, ezinganyangekiyo ze-neurodeergenerative phakathi kwezilwanyana (BSE kunye neCWD) kunye nabantu (vCJD).
| Yintoni Prion? Igama elithi 'prion' sisifinyezo se-'proteinaceous infectious particle'. I-Prion Protein Gene (PRNP) ifaka iikhowudi a protein ebizwa ngokuba yiprion protein (PrP). Kumntu, i-prion protein gene PRNP ikhona kwi-chromosome inombolo ye-20. Iprotheni ye-prion eqhelekileyo ikhona kwi-cell surface ngoko ichazwa njenge-PrPC. 'Isuntswana elosulelayo eliyiproteinaceous' elidla ngokubizwa ngokuba yiprion luguqulelo olungasombulukanga lweprion protein PrP.C kwaye ichazwa njengePrPSc (Sc ngenxa yokuba luhlobo lwe-scrapie okanye uhlobo olungaqhelekanga olunxulumene nesifo esifunyenwe kwisifo se-scrapie kwiigusha). Ngexesha lokwenziwa kolwakhiwo lwenqanaba eliphezulu kunye ne-quaternary, ngamanye amaxesha, kukho iimpazamo kwaye iprotein ilahleka okanye imile kakuhle. Oku ngokuqhelekileyo kulungiswe kwaye kulungiswe kwifomu yokuqala eyenziwa yi-molecule ye-chaperone. Ukuba iprotheni egoqwe kakuhle ayilungiswa, ithunyelwa kwiproteolysis kwaye idla ngokuthotywa. Nangona kunjalo, iprotheni ye-prion ephosakeleyo inokuchasana neproteolysis kwaye ihlale ingaphantsi kwaye iguqule iprotheni ye-prion PrP eqhelekileyo.C kwifomu ye-scrapie engaqhelekanga PrPSc kubangela iproteopathy kunye nokungasebenzi kakuhle kweeseli ezikhokelela kwizifo ezininzi zemithambo-luvo ebantwini nakwizilwanyana. I-scrapie pathological form (PrPSc) yahluke ngokwesakhiwo kwiprotheni eqhelekileyo yeprion (PrPC). Iprotein yeprion eqhelekileyo inama-43% e-alpha helices kunye ne-3% ye-beta sheets ngelixa ifom ye-scrapie engaqhelekanga inama-30% e-alpha helices kunye ne-43% ye-beta sheets. Ukuxhathisa kwePrPSc kwiprotease enzyme kubalelwa kwipesenti ephezulu ngokungaqhelekanga yamaphepha e-beta. |
Izifo ezingapheliyo zokumosha (CWD), ekwabizwa ngokuba yi Isifo seenyamakazi zeZombi sisifo esibulalayo se-neurodeergenerative esichaphazela izilwanyana zomlomo wesibeleko eziquka ixhama, i-elk, i-reindeer, i-sika deer kunye ne-moose. Izilwanyana ezichaphazelekayo zilahlekelwa kakhulu yimisipha ekhokelela ekunciphiseni ubunzima kunye nezinye iimpawu ze-neurologic.
Ukususela ekufumaneni kwayo ekupheleni kwe-1960s, i-CWD isasazeke kumazwe amaninzi aseYurophu (eNorway, eSweden, eFinland, e-Iceland, e-Estonia, eLatvia, eLithuania nasePoland), eMntla Melika (e-USA naseKhanada) nase-Asia (eMzantsi Korea).
Akukho nolunye uhlobo lwe-CWD prion. Iintlobo ezahlukeneyo ezilishumi zibonakaliswe ukuza kuthi ga ngoku. Ubunzima obuchaphazela izilwanyana eNorway nakuMntla Merika zahlukile, kunjalo ke nohlobo oluchaphazela ixhama laseFinland. Ngapha koko, iinguqulelo ezintsha zinokuvela kwixesha elizayo. Oku kubangela umngeni ekuchazeni nasekunciphiseni esi sifo kwimibeleko yesibeleko.
I-CWD prion isasazeka kakhulu into echaphazelekayo kuluntu lwesibeleko kunye nempilo yoluntu yoluntu.
Akukho nyango okanye amayeza akhoyo ngoku.
Izifo ezingapheliyo zokumosha (CWD) AYIFUMANANI ebantwini ukuza kuthi ga ngoku. Akukho bungqina bubonisa ukuba iiprions zeCWD zinokosulela abantu. Nangona kunjalo, uphando lwezilwanyana lubonisa ukuba izilwanyana ezingezona abantu ezidlayo (okanye, zidibana nengqondo okanye ulwelo lomzimba) izilwanyana ezosulelwe yi-CWD zisengozini.
Kukho inkxalabo malunga nokusasazeka kwe-CWD prions ebantwini, mhlawumbi ngokutyiwa kwenyama yexhama okanye i-elk eyosulelekileyo. Ngoko ke, kubalulekile ukuyigcina loo nto ingangeni emntwini ukutya Ikhonkco.
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Iingxelo:
- Amaziko oLawulo lweSifo kunye noThintelo (CDC). Izifo ezingapheliyo zokumosha (CWD). Ifumaneka e https://www.cdc.gov/prions/cwd/index.html
- Atkinson CJ okqhubekayo 2016. I-Prion protein scrapie kunye neprotheni ye-prion eqhelekileyo yeselula. Prion. 2016 Jan-Feb; 10(1): 63–82. DOI: https://doi.org/10.1080/19336896.2015.1110293
- Ilanga, JL, okqhubekayo 2023. Inoveli yePrion Strain njengoMbangela weSifo esiNcinci sokumosha kwiMoose, eFinland. Izifo eziKhuselekileyo eziKhuselekileyo, i-29 (2), i-323-332. https://doi.org/10.3201/eid2902.220882
- Otero A., okqhubekayo 2022. Ukuvela kweentlobo ze-CWD. I-Cell Tissue Res 392, 135-148 (2023). https://doi.org/10.1007/s00441-022-03688-9
- Mathiason, CK Iimodeli ezinkulu zezilwanyana zesifo esingapheliyo sokumosha. I-Cell Tissue Res 392, 21-31 (2023). https://doi.org/10.1007/s00441-022-03590-4
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