I-methylene blue, i-Prussian blue, ne-hydroxocobalamin: amayeza amathathu okuchasana netyhefu kwiingxaki ezahlukeneyo

Amayeza amathathu anegama lombala elifanayo kodwa phantse ayinanto yimbi afana ngayo. I-methylene blue yidayi eluhlaza okwesibhakabhaka ye-redox. I-Prussian blue sisakhiwo seekristale esiluhlaza okwesibhakabhaka. I-hydroxocobalamin, ethengiswa njenge-Cyanokit, sisandulela esibomvu sevithamini B12. Umfundi owabeka ndawonye ngokwamagama awo unokucinga ukuba enza umsebenzi ofanayo. Akunjalo. Ngalinye lisekelwe kwingcamango eyahlukileyo yento engahambi kakuhle emzimbeni, kwaye ngalinye alisebenzi ngaphandle kwaloo meko.

Unxulumano olucacileyo lufutshane. I-methylene blue ibuyisela ukusebenza kwehemoglobin ethe yayeka ukusebenza ngenxa ye-oxidation. I-hydroxocobalamin ibophelela icyanide ngokuthe ngqo. I-Prussian blue ibamba icesium enemitha ne-thallium ngaphakathi emathunjini ukuze umzimba uzikhuphe. Umbala yinto ebonakalayo. Indlela esebenza ngayo sisiseko sengcamango, kwaye ukudibanisa umbala naloo ndlela yokusebenza kulapho kuvela khona ukubhideka.

Olu luthelekiso lokufundisa, hayi isikhokelo sonyango. Ukukrokrelwa kwe-methemoglobinemia, ukuvezwa kwicyanide, ukuvezwa kwicarbon monoxide, okanye ungcoliseko lwemitha yimeko engxamisekileyo. Tsalela iinkonzo ezingxamisekileyo uze ulandele iingcebiso zendawo zolawulo lwetyhefu kunokuba wenze okuthile usekelwe kwinqaku.

I-methylene blue: umdlulisi obuyisela ukusebenza kwehemoglobin

Ihemoglobin eqhelekileyo ithwala ioksijini ngentsimbi ekwimo ye-ferrous, Fe2+. Kwi-methemoglobinemia loo ntsimbi iye yatshintshwa yi-oxidation yaba kwimo ye-ferric, Fe3+, engakwaziyo ukubophelela ioksijini. Igazi linokubonakala limdaka njengeshokolethi. Umlinganiselo oqhelekileyo weoksijini ngesixhobo esisebenzisa ukubetha kwemithambo unokulahlekisa. Isigulana sinehemoglobin esebenzayo enganelanga nangona imiphunga ingenisa ikhupha umoya.

I-methylene blue iyasebenza kule meko kuba ingumdlulisi weeelectron, njengoko kuchaziwe kwindlela i-methylene blue ehambisa ngayo iielectron phakathi kwabanikeli nabamkeli. Ngaphakathi kwiiseli ezibomvu zegazi, iyancitshiswa ibe yi-leucomethylene blue ngendlela exhomekeke kwi-NADPH, kwaye loo mo incitshisiweyo inika intsimbi ye-ferric iielectron ngaphandle kokusebenzisa ii-enzyme, iyibuyisela kwimo ye-ferrous. Idayi iyajikeleza endaweni yokuphela xa isetyenziswa. Loo ndlela yokusebenza sisizathu sokuba ukusetyenziswa kwe-methylene blue kwi-methemoglobinemia kube yinkqubo yasesibhedlele apho kulinganiswa amanqanaba kuze kujongwe impendulo, kungekhona inkqubo yasekhaya.

Ileyibhile yangoku ye-methylene blue ichaza ukusetyenziswa okuvunyiweyo njenge-methemoglobinemia efunyenweyo kubantu abadala nakubantwana, ngedosi eqhelekileyo yabantu abadala neyabantwana eyi-1 mg nge-kg, efakwa emthanjeni kwisithuba semizuzu emi-5 ukuya kwengama-30, enokuphindwa kube kanye ukuba amanqanaba okanye iimpawu ziyaqhubeka. Iinkcukacha zemida yedosi, imiqathango yokuyiphinda, nexesha lokutshintshela kolunye ungenelelo zichazwe kwileyibhile yangoku ye-methylene blue, kwaye imibuzo esebenzayo yendlela yokuyinika nokubeka iliso ichazwa kwindlela i-methylene blue enikwa ngayo ngedosi nenokubekwa ngayo iliso.

Imida emithathu ibalulekile. Okokuqala, ukunqongophala kwe-glucose-6-phosphate dehydrogenase sisithintelo esisemthethweni sokusetyenziswa, kuba unikezelo lwe-NADPH olufunekayo ukunciphisa idayi luyaphazamiseka, nto leyo eyenza iyeza lingasebenzi ize inyuse umngcipheko wokonakala kweeseli ezibomvu zegazi. Okwesibini, i-methylene blue ithintela i-monoamine oxidase A kubuninzi obulinganiswa ngeenanomolar, ngoko ukuyinika kunye nee-SSRI, ii-SNRI, ii-MAOI, kunye nee-opioid eziliqela kunesilumkiso esikwibhokisi malunga ne-serotonin syndrome, umba oxoxwa kukhuseleko lwe-methylene blue nokusebenzisana kwayo namanye amayeza. Okwesithathu, ukungasebenzi kakuhle kwezintso kutshintsha ubungakanani bokuchanabeka komzimba kweli yeza, kwaye ileyibhile imisela ukuba izigulana ezinokungasebenzi kakuhle okuphakathi okanye okukhulu zifumane idosi enye kuphela. Akukho nanye kwezi engumbandela omncinane. Nganye ivela kwakwingcamango enye yokudlulisa: iyeza eliboleka unikezelo lweeelectron zeseli nelichaphazela ii-enzyme ze-monoamine liya kusebenzisana nazo zombini.

I-methylene blue nayo inembali ekunyangeni ityhefu yecyanide, eqala ngeminyaka yee-1930s, kodwa imbali ayiyonkqubo yangoku. Abaphandi bokuqala bacebisa iziphumo ezibangelwa yi-redox okanye ezilamlelwa yi-methemoglobin, kwaye ngeminyaka yee-1950s iyeza lagwetywa njengelingasebenzi ngokwaneleyo kwicyanide xa lithelekiswa neendlela ze-nitrite ne-thiosulfate. Namhlanje alivunyelwanga ukunyanga ityhefu yecyanide e-US. Izifundo ezihlaziyiweyo ngeempuku neeseli malunga necyanide ziimpawu zophando lwangaphambi kovavanyo ebantwini, hayi isizathu sokulisebenzisa kwimeko engxamisekileyo yecyanide.

I-hydroxocobalamin: iziko lecobalt elibophelela icyanide

Icyanide ivala i-cytochrome c oxidase kwiimitochondria, ngoko iiseli azikwazi ukusebenzisa ioksijini nokuba ioksijini esegazini lemithambo ibonakala yanele. Oku kulandelwa yi-lactic acidosis, ukutshintsha kwengqondo, kunye nokusilela kwenkqubo yentliziyo nemithambo yegazi. Ingcamango yonyango kukususa icyanide ngokwayo, hayi ukutshintsha ihemoglobin.

I-hydroxocobalamin, ethengiswa njenge-Cyanokit, ikwenza oko ngokuthe ngqo. Iziko layo lecobalt libophelela i-ion yecyanide endaweni ye-hydroxo ligand yayo, lenze i-cyanocobalamin, eyivithamini B12 eqhelekileyo, ekhutshwa zizintso. Oku kukubamba nokwahlula, hayi ukujikeleza kwe-redox. Idosi evunyiweyo yabantu abadala yi-5 g efakwa emthanjeni kwisithuba esimalunga nemizuzu eli-15, kuze kunikwe enye i-5 g ukuba impendulo ayonelanga, ukuya kubuninzi be-10 g. Yiloo nto uthelekiso lwe-methylene blue ne-Cyanokit lusonjululwa ngokukhawuleza xa umbuzo ubekwe ngokuchanekileyo: kwityhefu yecyanide eyaziwayo okanye ekrokrelwayo, i-hydroxocobalamin liyeza langoku lokuqala elisetyenziswayo eUnited States, kunye nemveliso eyahlukileyo ye-nitrite ne-thiosulfate kwiimeko ezikhethiweyo. I-methylene blue ayinakuthatha indawo yayo kuloo msebenzi.

Zimbini iziphumo ezisebenzayo ezivela kwikhemistri yayo. Iyeza libomvu kakhulu, ngoko ububomvu bolusu nomchamo bulindelekile, yaye ukutshintsha kombala womchamo ngamanye amaxesha kuthatha iiveki. Ukufunxa kwalo ukukhanya ngamandla kukwaphazamisa iimvavanyo zaselabhoratri ezilinganisa umbala kunye nemilinganiselo ye-co-oximetry ye-carboxyhemoglobin, i-methemoglobin, ne-oxyhemoglobin, ubukhulu necala lempazamo buhluka ngokwesixhobo sokuhlalutya. Ugqirha ongakwaziyo oku unokufunda gwenxa kwaamanani asetyenziselwa ukuvavanya ityhefu. Ikhithi yakudala yecyanide esekelwe kwi-amyl nitrite, i-sodium nitrite, ne-sodium thiosulfate yayisebenza ngokwahlukileyo: i-nitrite yayisenza i-methemoglobin ngabom ukuze ibophelele icyanide, ngoxa i-thiosulfate yayinceda ukuguqula icyanide ibe yi-thiocyanate. Elo qhinga linciphisa amandla okuthwala ioksijini kwaye linokuthoba uxinzelelo lwegazi, nto leyo engeyiyo inzuzo xa ukuphefumla umsi kuthetha ukuba necarbon monoxide isenokuba ikhona. I-hydroxocobalamin iyayiphepha loo lahleko ngokubophelela icyanide ngaphandle kokwenza i-methemoglobin.

I-Prussian blue: isibambisi seekristale esihlala emathunjini

I-Prussian blue, ethengiswa njenge-Radiogardase, yi-ferric hexacyanoferrate enganyibilikiyo. Igama elithi cyanide kuloo fomyula lichaza ii-ligand ezivalelwe kwikristale yentsimbi, hayi icyanide ekhululekileyo, kwaye ayinandima ekunyangeni ityhefu yecyanide. Ukusetyenziswa kwayo okuvunyiweyo kukungcoliseka ngaphakathi emzimbeni yicesium enemitha okanye yi-thallium enemitha okanye engenamitha.

Ingcamango yayo kukutshintshiselana kwee-ion ngaphakathi emathunjini. Iikristale azifunxwa ngodonga lwamathumbu olungonakalanga. Zihlala emathunjini, zibambe ii-ion zecesium okanye ze-thallium kwisakhiwo seekristale, kuquka ii-ion ezikhutshwa kwinyongo, zize ziphazamise ukuphinda zijikeleze phakathi kwamathumbu nesibindi ukuze intsimbi eninzi iphume kwilindle. Iphepha le-CDC lonyango nge-Prussian blue lichaza kwaloo ndlela ngamagama alula: ibamba ezi ntsimbi emathunjini ize ikhawulezise ukukhutshwa kwazo ngelindle. Inkqubo yabantu abadala nabafikisayo yi-3 g ngomlomo kathathu ngemini, ngeedosi eziphantsi ezisekelwe kubunzima babantwana abancinane, yaye idla ngokuqhubeka iintsuku ezingama-30 okanye ngaphezulu ngoxa kubekwa iliso kungcoliseko.

Oku kuchaza ngokuthe ngqo uphendlo oluthelekisa i-Prussian blue ne-methylene blue. I-methylene blue isebenza egazini njengomdlulisi weeelectron. I-Prussian blue isebenza emathunjini njengesibambisi esingafunxwayo. Enye ibuyisela ukusebenza kweprotheyini equlethe intsimbi. Enye inciphisa ixesha lokuhlala kwentsimbi emzimbeni. Ukuzitshintshanisa kungashiya zombini iingxaki zinganyangwanga: i-methemoglobin ingahlala ikwimo ye-oxidation, ize icesium iqhubeke nokuphinda ijikeleze.

Icarbon monoxide: apho i-methylene blue ingenandawo khona

Icarbon monoxide ibophelela kwihemoglobin ngamandla angaphezulu kakhulu kuneoksijini ize itshintshe igophe lokwahlukana kwayo neoksijini, ngoxa ikwasebenza kwiindawo zentliziyo nezemitochondria. Unyango oluqhelekileyo kukususa umntu kwindawo yokuchanabeka kunye nokumnika ioksijini eyi-100 ekhulwini de iimpawu ziphele, ngokuqhelekileyo kangangeeyure eziliqela, kuze kuqwalaselwe ioksijini enikwa phantsi koxinzelelo oluphezulu kwiimeko ezithile ezinzima ezifana nokuphazamiseka okukhulu kwenkqubo yemithambo-luvo, ukungabikho zingqondweni, ukuchaphazeleka kwentliziyo, okanye i-acidosis enzima. Imithombo karhulumente wobumbano yeemeko ezingxamisekileyo eqokelelwe kwingqokelela ye-CDC yemithombo yonyango olungxamisekileyo ibeka ioksijini nonyango oluxhasayo embindini wale ndlela.

Ngoko ke uphendlo lwe-methylene blue kwityhefu yecarbon monoxide lusekelwe kwimpazamo evakala isengqiqweni: ukuba idayi eluhlaza okwesibhakabhaka ilungisa enye ingxaki yehemoglobin, mhlawumbi ilungisa nenye. Ayenzi njalo. Iyeza alinako ukusetyenziswa okuvunyiweyo kwicarbon monoxide, kwaye iinkqubo zangoku zonyango lwecarbon monoxide azilibandakanyi. Le ngcamango indala, yacetyiswa kuphando lwezilwanyana ekuqaleni kweminyaka yee-1930s yaza yakhatywa luvavanyo oluyigxekayo kwisithuba sonyaka, kwaye uphando olunye lwangoku ngeempuku olukhankanywa ngamanye amaxesha lwavavanya ukhuseleko olubambezelekileyo lwemithambo-luvo emva kokuchanabeka kunokuba luvavanye ukubuyiselwa ngokukhawuleza kwe-carboxyhemoglobin. Intsimbi etshintshwe yi-oxidation nentsimbi ebotshelelwe yicarbon monoxide ziimo ezahlukeneyo zeprotheyini enye, kwaye umdlulisi olungiselelwe eyokuqala akanamsebenzi uqinisekisiweyo kweyesibini. Abafundi abalandela lo mda baya kuwufumana uluncedo xa ujongwa kunye nembonakalo ebanzi yophando lwe-methylene blue, eyahlula ukusetyenziswa okuvunyiweyo ebantwini kwiimpawu ezivela kuphando lweeseli nezilwanyana.

Ukujonga ecaleni komnye nomnye ngaphambi kwalo naluphi na uthelekiso

Thelekisa loo theyibhile neempazamo ezintathu eziqhelekileyo. Amagama afanayo awathethi ukuba zijolise kwizinto ezifanayo. Umbala oqaqambileyo awuthethi ukuba zineempawu ezifanayo zamayeza; ububomvu be-hydroxocobalamin nobuluhlaza okwesibhakabhaka bezinye ezimbini abutsho nto ngokukwazi kwazo ukutshintshana. Kwaye isiphumo sovavanyo kolunye uhlobo lwetyhefu asidluliselwa kolunye uhlobo lwetyhefu oluvakala nje lusondelelene nalo. Kuqala iingcamango, kulandele iileyibhile, kwaye izigqibo ezingxamisekileyo zenziwe kunye noogqirha beenkonzo ezingxamisekileyo.