I-methylene blue kuvavanyo lwe-G6PD elebhu: eyona nto yenziwa yile dayi

Umfundi ubukela iityhubhu ezimbini emva kokuzifukamisa. Enye ijike yanombala olindelekileyo. Enye ayitshintshanga. Umfundi ugqiba kwelokuba isigulana sesibini sinokusilela kwe-glucose-6-phosphate dehydrogenase. Eso sigqibo sisenokuba sichanile, kodwa indlela acinga ngayo itsiba ingcamango eyenza olu vavanyo lusebenze. Akukho nto kwityhubhu ilinganisa i-enzayim ngokuthe ngqo. Ityhubhu ilinganisa oko kuveliswa yi-enzayim, isebenzisa i-methylene blue njengomlamli.

Xa sele kucacile ukuba umlinganiselo awenziwa ngokuthe ngqo, inkqubo, iisampulu zolawulo, noluhlu olude lweziphumo ezingachananga ziyeka ukubonakala ngathi azinasiseko.

Impendulo emfutshane

I-methylene blue kuvavanyo lwe-G6PD sisalathisi se-redox. I-enzayim i-G6PD ivelisa i-NADPH, yaye iinkqubo ezixhomekeke kwi-NADPH zinciphisa i-methylene blue eluhlaza okwesibhakabhaka iye kwimo yayo ye-leuco engenambala (okanye ziyisebenzise ukuhambisa ii-elektroni). Ukusebenza okuqhelekileyo kwe-enzayim kubangela ukuncitshiswa okusebenzayo. Ukusebenza okusilelayo kubangela ukuncitshiswa okucothayo okanye okungagqitywanga. Yiyo yonke loo nto iboniswa luvavanyo.

Iindlela ezimbini zembali zisebenzisa idayi enye kodwa zahlukile kwinto ebonisa isiphelo sovavanyo. Ukuba uyazahlula, uninzi lokubhideka luyaphela.

Iimvavanyo ezimbini, idayi enye, izalathisi zesiphelo ezahlukeneyo

Olokuqala luvavanyo lokuncitshiswa ngokuthe ngqo kwe-methylene blue, olwachazwa nguSass noogxa bakhe lwaza kamva lwavavanywa nguGibbs. Apha isalathisi sesiphelo yidayi ngokwayo: i-methylene blue eluhlaza okwesibhakabhaka ekwimo ye-oksideshini iyancitshiswa isondela kwi-leucomethylene blue engenambala, yaye isantya solo tshintsho sibonisa amandla okuvelisa i-NADPH. Iphepha lokuqala lolu vavanyo lokuhlola lidweliswe kwi-PubMed phantsi kukaSass noogxa bakhe (1966).

Olwesibini luvavanyo lwe-Brewer lokuncitshiswa kwe-methemoglobin. I-sodium nitrite iqala ngokufaka i-hemoglobin kwioksideshini ibe yi-methemoglobin emdaka. Emva koko i-methylene blue isebenza njengomlamli wokudluliselwa kwee-elektroni: i-methylene blue encitshisiweyo idlulisela amandla okunciphisa kwi-methemoglobin, iyibuyisele kwi-hemoglobin ebomvu. Ngoko isalathisi sesiphelo esibonakalayo ngumahluko phakathi kombala omdaka nobomvu, hayi phakathi kombala oluhlaza okwesibhakabhaka nokungabi nambala. Indlela yokuqala yapapashwa kwi-Bulletin of the World Health Organization (Brewer noogxa bakhe, 1960).

Ukubiza uvavanyo lwe-Brewer ngokuba luvavanyo lokupheliswa kombala wedayi akuchananga ngokupheleleyo ngokwekhemistri. Idayi ijikeleza phakathi kweemo zayo; yi-hemoglobin etshintsha umbala. Umzobo ongezantsi ubonisa zombini iindlela.

Intsabelo esisiseko

I-G6PD ikhawulezisa inyathelo lokuqala le-oksideshini kwindlela ye-pentose phosphate:

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

Iiseli ezibomvu zegazi ezivuthiweyo zixhomekeke kakhulu kule ndlela ukuze zifumane i-NADPH, njengoko kuxoxwa kwi-Blood nguLuzzatto noogxa bakhe (2020). I-NADPH igcina i-glutathione ikwimo encitshisiweyo yaye ikhusela iseli kumonakalo we-oksideshini. I-methylene blue ingena kule nkqubo njengomamkeli wee-elektroni. I-G6PD eyaneleyo inika i-NADPH eyaneleyo, ekhokelela ekuncitshisweni okusebenzayo. I-G6PD ephantsi iqhawula eli khonkco kwikhonkco lalo lokuqala.

Cinga ngedayi njengesilinganisi samafutha, hayi njengenjini. Ibonisa ubukho be-NADPH. Nantoni na enye etshintsha obo bukho, okanye isiphumo esifundwayo, inokushenxisa inaliti ngaphandle kotshintsho kwimfuza.

Indlela eqhutywa ngayo inkqubo yohlobo lwe-Brewer

Iindlela zokulungisa ii-reagent ziye zahluka kumashumi eminyaka, ngoko ingcaciso yokufundisa mayingaphazanyiswa nenkqubo yekliniki. Ilebhu nganye ilandela inkqubo yayo yokusebenza esemgangathweni eqinisekisiweyo. Ngalo mqathango engqondweni, ulungiselelo lweetyhubhu lwakudala lusebenza ngolu hlobo lulandelayo, ngendlela ebhalwe ngeetyhubhu ezintathu nokufukamisa iiyure ezi-3 kule ndlela yokuphumeza epapashiweyo:

1. Ityhubhu yesigulana: igazi elipheleleyo kunye ne-glucose, i-sodium nitrite, ne-methylene blue. I-nitrite ivelisa i-methemoglobin, i-glucose ixhasa imetabolism yeeseli ezibomvu zegazi, yaye idayi ibonelela ngendlela yokuhambisa ii-elektroni exhomekeke kwi-NADPH.
2. Isampulu yolawulo efakwe kwioksideshini: igazi kunye ne-nitrite ne-glucose kodwa ngaphandle kwe-methylene blue. Ibonisa umbala omdaka we-methemoglobin ekupheleni kovavanyo, ongumfanekiso wokusilela.
3. Isampulu yolawulo ye-hemoglobin: igazi kunye namanzi. Ibonisa umbala obomvu we-hemoglobin ekupheleni kovavanyo, ongumfanekiso oqhelekileyo.
4. Fukamisa zonke iityhubhu kufutshane ne-37 C, ngokuqhelekileyo iiyure ezi-3, uzixuba ngobunono.
5. Xuba ngamanzi inxalenye encinci yesampulu yetyhubhu nganye, usebenzisa amanzi adistiliweyo ukuqhekeza iiseli nokwenza uthelekiso lombala lubonakale ngokucacileyo.
6. Thelekisa ityhubhu yesigulana neesampulu ezimbini zolawulo. Ukubuyela kumbala obomvu kubonisa amandla amakhulu okunciphisa. Ukuhlala kufutshane nombala omdaka kubonisa ukuba kusenokubakho ukusilela okukhulu.

Olunye ulungiselelo lwembali lwasebenzisa malunga ne-1 mL yegazi nee-reagent ezikufutshane ne-180 mM ye-sodium nitrite, i-280 mM ye-dextrose, ne-0.4 mM ye-methylene blue. La manani mawathathwe njengomzekelo ovela kuncwadi lwenzululwazi, hayi njengemilinganiselo esebenza kuyo yonke indawo.

Ukufunda isiphumo

Uvavanyo lokuhlola olungalinganisi bungakanani lwahlula kakuhle kufutshane nama-30 ukuya kuma-40 ekhulwini okusebenza okuqhelekileyo, njengoko kuxoxwa kolu hlalutyo lwe-Malaria Journal malunga nezikhewu ekufumaniseni i-G6PD. Ngoko isiphumo esiqhelekileyo sovavanyo lokuhlola sithetha ukuba uvavanyo alufumananga ukusilela okukhulu. Asiqinisekisi ukuba ukusebenza kuqhelekile ngokupheleleyo.

Kutheni ukuhlola kunokulahlekisa

Ukwanda kwee-reticulocyte emva kwe-hemolysis ngumzekelo oqhelekileyo wesiphumo esibonakala siqhelekile kodwa singachananga. Iiseli ezibomvu zegazi eziselula nee-reticulocyte zine-G6PD engaphezulu kuneeseli ezindala. Ngexesha lesiganeko se-hemolysis esiqatha, ezona seli zindala nezisilelayo kakhulu zisenokuba sele zitshatyalalisiwe, kushiyeke iqela leeseli eziselula ezibonisa ukusebenza okuqhelekileyo kuvavanyo. Le nkqubo yebhayoloji ikwalahlekisa iimvavanyo ezilinganisa ubungakanani, hayi iimvavanyo zokuhlola ngedayi kuphela.

Utofelo-gazi lwakutshanje lufihla ukusilela kuba iiseli ezibomvu zegazi zomnikeli zongeza i-enzayim yazo kwisampulu. I-Mayo Clinic Laboratories idwelisa utofelo-gazi phakathi kwezizathu zeziphumo ze-enzayim ezingathembekanga, kunye nokwanda kwee-reticulocyte nokuphazamiseka okubangelwa ziiseli ezimhlophe zegazi.

Abasetyhini abane-heterozygosity ngabona banzima ukuvavanya. Ukungasebenzi kwe-X-chromosome okwenzeka ngokungakhethiyo kuvelisa umxube weeseli ezibomvu zegazi eziqhelekileyo nezisilelayo, yaye ukusebenza kwazo xa zizonke kunokuba naphi na phakathi kokusilela okukhulu nokubonakala kuqhelekile. Iimvavanyo zokuhlola ezingalinganisi bungakanani zihlala ziphoswa zii-phenotype eziphakathi. Amaxwebhu e-WHO ngovavanyo lwe-G6PD axoxa ngalo mda ngokweenkcukacha.

Ubudala besampulu, iqondo lobushushu lokugcinwa kwayo, ukuxhomekeka kombala wesiphelo kwindlela umntu awubona ngayo, i-hematocrit, nomgangatho wee-reagent zongeza ukuphazamiseka kuhlalutyo phezu kwale miphumo yebhayoloji.

Ukuhlola asikokuxilonga

Isiphumo sovavanyo lokuhlola esibonisa ukusilela, esiphakathi, okanye esingahambelaniyo nemeko yekliniki sifuna uvavanyo lwe-enzayim ye-G6PD olulinganisa ubungakanani. I-WHO ithatha i-spectrophotometry yokulinganisa ubungakanani, eneqondo lobushushu elilawulwayo, njengendlela esisiseko sokuthelekisa. Kolo vavanyo, isampulu yeeseli ezibomvu zegazi eziqhekeziweyo ifumana i-glucose-6-phosphate ne-NADP+, yaye i-NADPH eyenziwayo ilandelwa ngokunyuka kokufunxwa kokukhanya kwi-340 nm. Isantya sotshintsho silingana nokusebenza kwe-enzayim, ngokuqhelekileyo okulungelelaniswa nesixa se-hemoglobin njengeeyunithi ngegram. Iindlela zangoku zeelebhu zekliniki zishwankathelwe kwinqaku lekhathalogu yovavanyo lwe-Mayo ngokusebenza kwe-G6PD.

Ukutolikwa kusebenzisa uluhlu lwamaxabiso esalathiso oluqinisekiswe yilebhu, oludla ngokusekelwa ekusebenzeni okuqhelekileyo kuluntu, kuxoxwe ngokusilela kufutshane nomda wama-30 ekhulwini nangokusebenza okuphakathi ngaphezu kwawo. Iinkcazelo ze-WHO zeempawu ezijoliswe kuzo kwiimveliso zovavanyo lwe-G6PD (2022) zichaza eso sikhokelo sokuxilonga. Ukuba i-hemolysis okanye utofelo-gazi lwakutshanje lwenza ukumiselwa kwe-phenotype kungathembeki, phinda uvavanyo emva kokuba iqela leeseli ezibomvu zegazi libuyele ekulinganeni, yaye uvavanyo lwemolekyuli lunokongeza ulwazi ngaphandle kokuthatha indawo yokulinganiswa kwe-enzayim.

Umda ofanele ugcinwe

I-methylene blue kwezi mvavanyo yi-reagent yelebhu esetyenziswa ngaphandle komzimba. Loo nto yeyengxoxo eyahlukileyo kukhuseleko lokunika isigulana i-methylene blue, oluxoxwa kwisikhokelo seemeko apho i-methylene blue ingafanele isetyenziswe. Ibhayokhemistri iyazidibanisa, kuba iyeza nalo lixhomekeke ekuncitshisweni okuxhomekeke kwi-NADPH, kodwa idayi ekwityhubhu yovavanyo ayiyodosi esegazini. Ukuze uqonde indlela idayi esebenza ngayo njengedayi yokudyobha kwenye imeko, jonga imigaqo yokudyobha nge-methylene blue, uze, ukuze uqonde iqela layo ngokwekhemistri, ujonge iidayi ze-redox elebhu.

Ukuhlola kubuza ukuba amandla okunciphisa abonakala esebenza ngokupheleleyo na. Ukuqinisekisa kubuza ukuba ingakanani na i-enzayim ekhoyo ngokwenene. Idayi iwuphendula kakuhle umbuzo wokuqala, ukuba akukho mntu uyicela ukuba iphendule owesibini.