Ubururu bwa metilene mu bipimo bya G6PD muri laboratwari: icyo irangi rikora mu by'ukuri

Umunyeshuri yitegereza utuyoboro tubiri tw'igerageza nyuma yo kutugumisha ku bushyuhe bwagenwe. Kamwe kahinduye ibara nk'uko byari byitezwe. Akandi ntikabikoze. Umunyeshuri ahita yanzura ko umurwayi wa kabiri afite ubuke bwa glucose-6-phosphate dehydrogenase. Uwo mwanzuro ushobora kuba ari wo, ariko uko yawugezeho birengagiza ihame rituma iki kipimo gikora. Nta kintu kiri mu kayoboro gipima enzime ubwayo mu buryo butaziguye. Akayoboro gapima icyo enzime ikora, gakoresheje ubururu bwa metilene nk'umuhuza.

Iyo ubu buryo bwo gupima binyuze ku kindi kintu bumaze kumvikana, intambwe z'ikizamini, ingero zo kugereranya n'urutonde rurerure rw'ibisubizo bitari byo ntibiba bikigaragara nk'ibintu byashyizweho nta mpamvu.

Igisubizo kigufi

Ubururu bwa metilene mu bipimo bya G6PD ni ikimenyetso cy'ihererekanya rya elegitoroni. Enzime G6PD ikora NADPH, maze sisitemu zishingiye kuri NADPH zigaha elegitoroni ubururu bwa metilene bukiri ubururu, bukajya mu miterere yabwo ya leuco itagira ibara (cyangwa zikabukoresha mu guhererekanya elegitoroni). Imikorere isanzwe ya enzime ituma irangi ryakira elegitoroni neza. Imikorere idahagije ituma kwakira elegitoroni bigenda buhoro cyangwa ntibirangire. Icyo ni cyo kimenyetso cyose ikipimo gitanga.

Uburyo bubiri bwa kera bukoresha irangi rimwe ariko bugatandukana ku kimenyetso cya nyuma gisomwa. Iyo butavanzwe, urujijo rwinshi rurashira.

Ibipimo bibiri, irangi rimwe, ibimenyetso bya nyuma bitandukanye

Icya mbere ni ikipimo cyo kwakira elegitoroni k'ubururu bwa metilene mu buryo butaziguye, cyasobanuwe na Sass na bagenzi be, nyuma gisuzumwa na Gibbs. Aha ikimenyetso cya nyuma ni irangi ubwaryo: ubururu bwa metilene buri mu miterere yatakaje elegitoroni bwakira elegitoroni bukagenda buhinduka leucomethylene blue itagira ibara, kandi umuvuduko w'iryo hinduka ugaragaza ubushobozi bwo gukora NADPH. Inyandiko y'ibanze yerekeye iri suzuma iboneka kuri PubMed munsi ya Sass na bagenzi be (1966).

Icya kabiri ni ikipimo cya Brewer cyo guha elegitoroni methemoglobine. Nitrite ya sodiyumu ibanza gutuma hemoglobine itakaza elegitoroni igahinduka methemoglobine y'umukara wijimye. Ubururu bwa metilene bukora nk'umuhuza mu ihererekanya rya elegitoroni: ubururu bwa metilene bwamaze kwakira elegitoroni buzigeza kuri methemoglobine, bukayihindura hemoglobine itukura. Bityo, ikimenyetso cya nyuma kigaragara ni ibara ry'umukara wijimye ugereranyije n'umutuku, si ubururu ugereranyije no kutagira ibara. Uburyo bwa mbere bwasohotse mu Kinyamakuru cy'Umuryango Mpuzamahanga wita ku Buzima (Brewer na bagenzi be, 1960).

Kwita ikipimo cya Brewer ikipimo cyo gukuraho ibara ry'irangi ntibisobanutse neza mu rwego rwa shimi. Irangi risimburana hagati y'imimerere yaryo; hemoglobine ni yo ihindura ibara. Igishushanyo gikurikira kigaragaza izo nzira zombi.

Igikorwa cya shimi iki kipimo gishingiyeho

G6PD yihutisha intambwe ya mbere yo gutakaza elegitoroni mu nzira ya pentose phosphate:

Glucose-6-phosphate + NADP+ ihinduka 6-phosphogluconolactone + NADPH + H+

Uturemangingo dutukura tw'amaraso dukuze dushingira cyane kuri iyi nzira kugira ngo tubone NADPH, nk'uko bisobanurwa mu nyandiko ya Luzzatto na bagenzi be muri Blood (2020). NADPH ituma glutathione iguma mu miterere yakiriye elegitoroni kandi ikarinda akaremangingo kwangizwa no gutakaza elegitoroni. Ubururu bwa metilene bwinjira muri iyi sisitemu nk'ikintu cyakira elegitoroni. G6PD ihagije itanga NADPH ihagije, na yo igatuma kwakira elegitoroni bigenda neza. G6PD nke ica uru ruhererekane ku ntambwe yarwo ya mbere.

Tekereza irangi nk'igipimo cyerekana lisansi isigaye, aho kuritekereza nka moteri. Rigaragaza uko NADPH iboneka. Ikindi kintu cyose gihindura uko NADPH iboneka, cyangwa uko igisubizo gisomwa, gishobora guhindura igipimo nta mpinduka yabaye muri jene.

Uko uburyo bw'ikipimo cya Brewer bukorwa

Uko imiti y'igerageza itegurwa kwagiye guhinduka mu myaka mirongo ishize, bityo ibisobanuro bigenewe kwigisha ntibigomba kwitiranywa n'amabwiriza yo gupima mu buvuzi. Buri laboratwari ikurikiza amabwiriza yayo y'imikorere asanzwe yemejwe. Ukizirikana icyo cyitonderwa, uburyo bwa kera bwo gukoresha utuyoboro bukorwa mu buryo bukurikira, nk'uko bwanditswe hakoreshejwe utuyoboro dutatu tugumishwa ku bushyuhe bwagenwe mu gihe cy'amasaha 3 muri ubu buryo bwashyizwe mu bikorwa bukanatangazwa:

1. Akayoboro k'umurwayi: amaraso yose hiyongereyeho glucose, nitrite ya sodiyumu n'ubururu bwa metilene. Nitrite ikora methemoglobine, glucose igatanga ibikenerwa mu bikorwa by'uturemangingo dutukura, naho irangi rigatanga uburyo bwo guhererekanya elegitoroni bushingiye kuri NADPH.
2. Urugero rwo kugereranya rwatakaje elegitoroni: amaraso hiyongereyeho nitrite na glucose ariko nta bururu bwa metilene. Rugaragaza ibara rya nyuma ry'umukara wijimye rya methemoglobine, ari ryo shusho y'ubuke bwa enzime.
3. Urugero rwa hemoglobine rwo kugereranya: amaraso hiyongereyeho amazi. Rugaragaza ibara rya nyuma ritukura rya hemoglobine, ari ryo shusho isanzwe.
4. Gumisha utuyoboro twose ku bushyuhe buri hafi ya 37 C, akenshi mu gihe cy'amasaha 3, uvanga buhoro.
5. Vanga agace gato k'ibiri muri buri kayoboro n'amazi yatunganyijwe hakoreshejwe kuyahindura umwuka no kongera kuwuhindura amazi, kugira ngo uturemangingo dushwanyuke kandi amabara ashobore kugereranywa neza.
6. Gereranya akayoboro k'umurwayi n'ingero ebyiri zo kugereranya. Gusubira ku ibara ritukura bigaragaza ubushobozi bugaragara bwo gutanga elegitoroni. Kuguma ku ibara ry'umukara wijimye byerekana ko hashobora kuba hari ubuke bukabije bwa enzime.

Uburyo bumwe bwa kera bwo gutegura iki kipimo bwakoreshaga amaraso agera kuri 1 mL hamwe n'imiti y'igerageza iri hafi ya 180 mM ya nitrite ya sodiyumu, 280 mM ya dextrose na 0.4 mM y'ubururu bwa metilene. Fata iyi mibare nk'urugero rwo mu nyandiko z'ubushakashatsi, aho kuyifata nk'amabwiriza akoreshwa hose.

Gusoma igisubizo

Isuzuma ry'ibanze ritanga igisubizo kidafite ingano ritandukanya neza ibisubizo hafi ya 30 kugeza kuri 40 ku ijana by'imikorere isanzwe, nk'uko bisobanurwa muri iyi nyandiko ya Malaria Journal isesengura ibyuho mu gutahura ubuke bwa G6PD. Bityo, igisubizo gisanzwe cy'isuzuma ry'ibanze gisobanura ko ikipimo kitatangiye ubuke bukabije. Nticyemeza ko imikorere ari isanzwe mu buryo bwuzuye.

Impamvu isuzuma ry'ibanze rishobora kuyobya

Ubwiyongere bwa reticulocytes nyuma yo gusenyuka kw'uturemangingo dutukura tw'amaraso ni bwo buryo buzwi cyane bwo kubona igisubizo gisanzwe kitari cyo. Uturemangingo dutukura tukiri duto na reticulocytes bifite G6PD nyinshi kurusha uturemangingo dushaje. Mu gihe cy'isenyuka ritunguranye ry'uturemangingo dutukura, uturemangingo dushaje cyane kandi dufite ubuke bukabije dushobora kuba twamaze gusenyuka, hagasigara uturemangingo tukiri duto imikorere yatwo igatanga igisubizo gisanzwe mu gipimo. Izi mpamvu zishingiye ku mikorere y'umubiri zinayobya ibipimo bitanga ingano, si ibipimo bikoresha irangi gusa.

Guhabwa amaraso vuba aha bihisha ubuke bwa enzime kuko uturemangingo dutukura tw'uwatanze amaraso twongeramo enzime yatwo mu cyitegererezo. Mayo Clinic Laboratories ishyira guhabwa amaraso mu bituma ibisubizo bya enzime bitizerwa, hamwe n'ubwiyongere bwa reticulocytes n'ukwivanga kw'uturemangingo twera tw'amaraso.

Abagore bafite kopi ebyiri zitandukanye za jene ya G6PD ni bo bagoye cyane gusuzuma. Guhagarikwa kw'imikorere ya kromozome X kutagengwa n'ihitamo runaka bituma habaho uruvange rw'uturemangingo dutukura dusanzwe n'udufite ubuke bwa enzime, kandi imikorere yabyo yose ishobora kuva ku buke bukabije ikagera ku isa n'isanzwe. Isuzuma ry'ibanze ritanga igisubizo kidafite ingano rikunze kutabona imikorere iri hagati. Inyandiko za WHO ku bipimo bya G6PD zisobanura uyu mupaka mu buryo burambuye.

Igihe cy'icyitegererezo, ubushyuhe kibikwaho, uko gusoma ibara rya nyuma bishingira ku muntu urireba, hematocrit n'ubuziranenge bw'imiti y'igerageza byongera urujijo mu isesengura hejuru y'izi ngaruka zishingiye ku mikorere y'umubiri.

Isuzuma ry'ibanze si ukwemeza ubuke bwa enzime

Igisubizo cy'isuzuma ry'ibanze cyerekana ubuke, imikorere iri hagati cyangwa kidahuye n'ibigaragara ku murwayi gisaba ikipimo gitanga ingano y'imikorere ya enzime G6PD. WHO ifata uburyo bwo gupima imikorere hakoreshejwe kwinjizwa kw'urumuri, ku bushyuhe bugenzurwa, nk'uburyo ngenderwaho. Muri icyo kipimo, hongerwa glucose-6-phosphate na NADP+ mu cyitegererezo cy'uturemangingo dutukura twashwanyujwe, maze NADPH ikozwe igakurikiranwa hakoreshejwe ukwiyongera kw'urumuri rwinjizwa kuri 340 nm. Umuvuduko w'ihinduka ujyana n'imikorere ya enzime, akenshi igahuzwa n'ingano ya hemoglobine ikagaragazwa mu bipimo kuri garama. Imikorere ikoreshwa ubu muri laboratwari z'ubuvuzi ivunagurwa mu nyandiko y'urutonde rw'ibipimo rwa Mayo yerekeye imikorere ya G6PD.

Gusobanura igisubizo bishingira ku ntera ngenderwaho yemejwe na laboratwari, akenshi igashyirwa mu rwego rwo kugereranya n'imikorere isanzwe mu baturage, ubuke bukavugwa kenshi hafi y'urugabano rwa 30 ku ijana, n'imikorere iri hagati ikaba hejuru yarwo. Ibisabwa WHO igena ku bipimo bya G6PD (2022) bisobanura urwo rwego rwo gusuzuma. Niba gusenyuka kw'uturemangingo dutukura cyangwa guhabwa amaraso vuba aha bituma kugena imiterere y'imikorere ya enzime bitizerwa, subiramo ikipimo nyuma y'uko uruvange rw'uturemangingo dutukura rusubiye mu buringanire; ibipimo bya molekile na byo bishobora kongera amakuru ariko ntibisimbure gupima enzime.

Itandukaniro rikwiye kubahirizwa

Ubururu bwa metilene muri ibi bipimo ni umuti w'igerageza ukoreshwa muri laboratwari hanze y'umubiri. Ibyo bitandukanye n'ikiganiro ku mutekano wo guha umurwayi ubururu bwa metilene, gisobanurwa mu mabwiriza ku bihe ubururu bwa metilene butagomba gukoreshwamo. Ibikorwa bya shimi byo mu binyabuzima birabihuza, kuko uwo muti na wo ushingira ku kwakira elegitoroni guturuka kuri NADPH, ariko irangi riri mu kayoboro k'igerageza si ingano y'umuti iri mu maraso. Kugira ngo umenye uko irangi rikora mu gusiga ingirabuzimafatizo mu bundi buryo, reba amahame yo gusiga hakoreshejwe ubururu bwa metilene; naho ku muryango wa shimi ribarizwamo, reba amarangi ahererekanya elegitoroni muri laboratwari.

Isuzuma ry'ibanze ribaza niba ubushobozi bwo gutanga elegitoroni busa n'ubukora neza. Ikipimo cyo kwemeza kibaza ingano ya enzime ihari mu by'ukuri. Irangi risubiza neza ikibazo cya mbere, igihe nta muntu urisaba gusubiza icya kabiri.