I-methylene blue ekwelapheni ubuthi be-nitrate ne-nitrite ezilwaneni ezinkulu

Umhlambi ungena ensimini yamabele ahlaselwe isomiso ntambama. Kusihlwa izinkomo eziningana sezisalele emuva, ziphefumula ngokushesha, zinolwelwesi olumnyama negazi elinsundu lapho kuhlatshwa umthambo ukuze kukhishwe igazi. Amahhashi asemadlelweni angomakhelwane abonakala engathintekile. Lo mehluko awubangelwa yinhlanhla. Uvela endaweni lapho i-nitrate iphenduka khona i-nitrite, futhi leyo ndawo inquma kokubili ukuxilongwa nohlelo lokusebenzisa ikhambi lokulwa nobuthi.

Iphuzu eliyinhloko lilula: i-nitrate ngokuyinhloko iyisandulela, i-nitrite iyona enobuthi, kanti i-methylene blue esetshenziswa ezinkomeni ezichayeke ku-nitrate yelapha umphumela we-nitrite ku-hemoglobin. Konke okunye okukulesi sihloko kulandela kulezo zinyathelo ezintathu.

I-nitrate iphenduka i-nitrite ngaphakathi kwesilwane

I-nitrate esefodweni ngokwayo iyisithako esibuthakathaka esibangela i-oxidation. Amagciwane aku-rumen ayiguqula ngokuyinciphisa ngezigaba ezimbili, kuqala i-nitrate ibe yi-nitrite, bese i-nitrite iba yi-ammonia. Lapho kufika umthamo omkhulu we-nitrate ngesikhathi esisodwa, isinyathelo sokuqala sishesha ngaphezu kwesesibili. I-nitrite iyanqwabelana, idlulele egazini, bese ibangela i-oxidation yensimbi eku-hemoglobin, iyisuse esimweni se-ferrous esithwala umoya-mpilo iye esimweni se-ferric. Umkhiqizo walokhu yi-methemoglobin, engakwazi ukuthutha umoya-mpilo.

Ukubuyekezwa kobuthi be-nitrate ne-nitrite ku-MSD Veterinary Manual kulinganisela ukuthi i-nitrite inobuthi obucishe buphindwe kayishumi kune-nitrate futhi kuchaza ukulandelana okufanayo. Imithombo evamile yizitshalo zefolishi ezinqwabelanisa i-nitrate njengama-oats, unyaluthi, i-ryegrass, ummbila, ubhekilanga namabele, kanye nokhula olufana ne-pigweed, i-lambsquarter, i-kochia ne-Johnson grass, ukudliwa komanyolo, namachibi noma imithombo engajulile engcoliswe amanzi ageleza phezu komhlabathi. Isomiso, ukusetshenziswa komanyolo omningi we-nitrogen, nokuma kokukhula ngemva kwesimo sezulu esinamafu noma esipholile kwandisa i-nitrate esefodweni.

Iphesenti le-methemoglobin lihlobene nobukhulu besimo kodwa hhayi ngokunembile ngokuphelele; nokho lokhu kuhlobana kuyasiza ekuhleleni ukuphuthuma kokunakekelwa. I-MSD ibeka izimpawu zokuqala njengokushaya kwenhliziyo ngokushesha, ubuthakathaka, ukuqhaqhazela nokungakwazi ukulawula ukunyakaza eduze kwamaphesenti angu-30 kuya ku-40 e-methemoglobin, ukuphefumula kanzima kakhulu okunolwelwesi olunsundu noma oluluhlaza okwesibhakabhaka ngaphezu kwamaphesenti acishe abe ngu-50, kanti ukufa kuvamise ukwenzeka kumaphesenti angu-80 noma ngaphezulu. Igazi elinsundu njengoshokoledi elihlala linsundu lapho lithintana nomoya liyisici esivamile, kodwa alifakazeli lesi simo lodwa, futhi i-methemoglobin ibuyela esimweni sayo ngokushesha ngokwanele ukuthi amasampula athathwe sekwephuzile abonise izinga eliphansi kuneliphezulu elalifinyelelwe. Ukuze kuqinisekiswe, i-MSD ikhetha ukuhlolwa kwe-nitrate ku-plasma ngaphambi kokufa nasoketshezini lweso ngemva kokufa, kuhambisane nokuhlaziywa kwefolishi namanzi. Amanani angaphezu kwe-nitrate ecishe ibe ngu-20 ppm noma i-nitrite engu-0.5 ppm kumasampula afanele athathwe emzimbeni ngokuvamile abonisa ukuchayeka ngokweqile.

Indlela i-methylene blue ebuyisela ngayo amandla okuthwala umoya-mpilo

Ngaphansi kwezimo ezivamile, iningi le-methemoglobin libuyiselwa esimweni salo ngokuncishiswa uhlelo lwe-NADH ne-cytochrome b5 reductase. I-methylene blue isebenzisa indlela yesibili, evame ukuba nendima encane. I-NADPH yamaseli, ekhiqizwa ngomzila we-pentose phosphate, idlulisa ama-electron nge-reductase encike ku-NADPH iye ku-methylene blue, iyiguqule ibe yi-leucomethylene blue, yona bese inciphisa insimbi ye-ferric iyibuyisele ku-hemoglobin ye-ferrous. Ukubuyekezwa kwale ndlela ku-StatPearls kuchaza le ndima yokuthwala ama-electron.

Le nqubo efanayo yamakhemikhali idala isexwayiso esiyinhloko. I-methylene blue iyisidakamizwa se-redox, hhayi nje isithako esivimbela i-oxidation kuphela. Uma igxile kakhulu, nayo ibangela i-oxidation, iphinde yakhe i-methemoglobin futhi ilimaze amaseli abomvu egazi. Yingakho ukusabela okungekuhle kufanele kushukumisele udokotela wezilwane ukuba aphinde ahlole ukuxilongwa, ukumuncwa okuqhubekayo ku-rumen, nesimo samaseli abomvu egazi, kunokuba avele aphinde anikeze amanani amakhulu. Indlela evamile yokucabanga esibhedlela, ehlanganisa ukuxilongwa nge-co-oximetry nokujova ngaphansi kokuqondiswa, ichazwe ku-methylene blue ekwelapheni i-methemoglobinemia.

Ukuqhathanisa izinhlobo nokuchayeka

Leli thebula lisiza ekuthatheni izinqumo. Umugqa ngamunye uhlanganisa indlela yokuchayeka, indawo yokuguquka, nalokho i-methylene blue engakwenza nengakwazi ukukwenza.

Izilwane ezetshisayo: izinkomo, izimvu nezimbuzi

Izinkomo yizona ezithinteka kaningi kakhulu, futhi izinkomba zezinsizakalo zokweluleka ngezolimo zivame ukuzibeka njengeqembu lemfuyo elisengozini enkulu kakhulu. Izimvu nezimbuzi nazo zisengozini ngokusobala kodwa zivame ukuchazwa njengezithinteka kancane kunezinkomo, mhlawumbe ngoba zisingatha imithwalo ye-nitrate ngokushesha. Bheka lokhu kuhlelwa njengomkhuba owusizo, hhayi njengento engaguquki eqinisekisiwe ngokwezamakhemikhali omzimba.

Ukulahleka kokuzala kufanele kunakwe ngokwehlukana. Izinkomazi ezisinda ku-methemoglobinemia enzima ethathe isikhathi eside zingaphuphuma noma zizale amathole afile ezinsukwini ezingaba ngu-5 kuya ku-14 kamuva, okuhambisana nokuntuleka komoya-mpilo embungwini. Ithole eliphile kahle ngakusasa ekuseni alifakazeli ukuthi ukuchayeka bekungatheni, kanti ukuphuphuma ngemva kwesonto akufakazeli ukuchayeka kwesibili.

Imithamo eshicilelwe ye-methylene blue yezinkomo iyehluka ngoba ivela ezinhlotsheni ezahlukene zobufakazi. Umbhalo wamanje we-MSD unikeza u-4 kuya ku-15 mg/kg noma ngaphezulu ngomthambo kancane, usebenzisa ingxube engamaphesenti angu-1 kuya ku-2, umthamo nokuphinda kunqunywe ubukhulu besimo nokumuncwa okuqhubekayo, futhi usho ngokusobala ukuthi yizilwane ezetshisayo kuphela ezibekezelela ngokuphepha amanani aphezulu. Eceleni kwaleyo nkomba kukhona izivivinyo ezincane nemibiko yasensimini: ukuhlolwa kwezinkomazi kwakudala kwathola ukuthi u-1 mg/kg wawanele ngaphansi kwezimo zako, ucwaningo lwezidakamizwa ezimvini lwahlola u-15 mg/kg ngomthambo, izivivinyo zezimbuzi zahlola u-1 kuya ku-4 mg/kg, amaqembu angu-4 mg/kg enza kangcono kakhulu, kanti imibiko yasensimini ichaza ukululama eduze kuka-4 mg/kg kanye nesigameko esisodwa esingajwayelekile senkomazi eduze kuka-20 mg/kg. Ucwaningo lwango-1984 ngokuhamba kwe-methylene blue emzimbeni wezimvu luyisibonelo esihle salolu hlobo: lusekela ukucabanga ngokubekezelelwa kwayo, hhayi ilebula yokusetshenziswa.

Ezinqumweni zikadokotela wezilwane nge-methylene blue ye-methemoglobinemia ezimvini, incazelo esebenzayo ukuthi alikho inani elilodwa elisebenza kuzo zonke izigameko. Ukukhiqizwa okuqhubekayo ku-rumen kusho ukuthi isilwane esilulamayo singaphinde sigule njengoba kumuncwa i-nitrite eyengeziwe, yingakho i-MSD ibopha ukuphinda ekuchayekeni okuqhubekayo kunasesimisweni esingaguquki. Ukunakekelwa okusekelayo kwenziwa kanye nalokhu: ukuphathwa okunciphisa ukucindezeleka ukuze kuncishiswe isidingo somoya-mpilo, ukususwa ekudleni nasemanzini okusolwayo, ukudla okuphephile esikhundleni sakho, nokunaka ukugeleza kwegazi ezicutshini. I-methylene blue ejovwayo iyacasula endaweni ejovwe kuyo, ngakho ukufinyelela okuphephile emthanjeni nokuyifaka kancane ngomthambo kubalulekile, futhi kufanele kulindelwe ukushintsha umbala kwezicubu, umchamo nezinzwa zemishini. Imikhawulo yodayi nezifutho ekwelapheni izilwane inikeza umongo wemikhawulo ebanzi ephathelene nezinhlobo.

Amahhashi ayindaba ehlukile

Amahhashi avubela i-fibre engxenyeni engemuva yamathumbu kunokuba ayivubele ku-rumen. Amagciwane aku-cecum anganciphisa i-nitrate, kodwa ukuguquka kuncane kakhulu kunasezinkomeni, ngakho amahhashi amadala ngokuvamile awasengozini enkulu ye-nitrate esefodweni. I-nitrite esivele yakhekile idlula lokhu kuvikeleka futhi ihlala iyingozi.

Nendlela yokucabanga ngekhambi lobuthi iyashintsha. Ocwaningweni lwakudala lokuqhathanisa ukulawulwa kwe-methemoglobin kumaseli abomvu egazi, i-methylene blue yandisa ukuncishiswa kwayo kumaseli abantu kodwa hhayi kumaseli amahhashi (ucwaningo ngamaseli abomvu egazi amahhashi). Izinkomba zesayensi yobuthi emahhashini zichaza ngokwehlukana ukuthi i-methylene blue ngokwayo ingabangela ukubhujiswa kwamaseli abomvu egazi okuhlobene nemizimba ye-Heinz nama-eccentrocyte ngenxa ye-oxidation, futhi zixwayisa ngokusetshenziswa kwayo ezimweni ezibangelwa yi-oxidation njengobuthi besihlahla se-maple esibomvu. Alikho kulawa maphuzu elifakazela ukuthi lesi sidakamizwa asisoze sasiza ihhashi elithile, kodwa uma ehlanganiswa avimba iphutha elivamile lokunciphisa inqubo yezinkomo ngokwesisindo. Ihhashi okusolwa ukuthi line-methemoglobinemia ebangelwa yi-nitrite lidinga ukuxilongwa kwalo, ukuhlonzwa kwesithako esibangela i-oxidation nokuhlolwa kwengozi, hhayi ithebula lemithamo yezilwane ezetshisayo.

Izilwane ezifuywayo nezinhlobo zama-aquarium zibonisa ukuthi kungani ukulinganisa ngesisindo kwehluleka

Amakati asenza sicace kakhulu isexwayiso. I-hemoglobin yamakati ithambekele ngokungajwayelekile ekushintsheni ukwakheka kwayo ngenxa ye-oxidation, futhi ukuchayeka okuphezulu noma okuphindaphindiwe ku-methylene blue kukhiqiza imizimba ye-Heinz nokubhujiswa kwamaseli abomvu egazi kunokuba kulaphe. Izinja azibuthakathaka njengamakati kulokhu kodwa zisabalwa phakathi kwezinhlobo ezizwela kakhulu ezifundweni zokuqhathanisa. Ukuchayeka kwezilwane ezifuywayo ezintweni ezibangela i-oxidation nakho kuhlukile ngohlobo, ngoba izidakamizwa, amakhemikhali nezigameko zokugwinya izinto yizona ezivame kakhulu kunokuba kube yi-nitrate yasemadlelweni.

Izinhlanzi zibonisa indlela ehluke ngokuphelele. I-nitrite ingena ngeziphefumulo, ngakho indawo esemqoka yokungenelela yisimo samakhemikhali samanzi, ikakhulukazi ukuncintisana kwe-chloride nokususwa kwe-nitrite, ngaphambi kwanoma yisiphi isidakamizwa. I-methylene blue yezinhlanzi ilinganiswa ngokugxila kwayo emanzini okucwiliswa kuwo, kubhekwa uhlobo, isikhathi, izinga lokushisa nemiphumela esihlungini sebhayoloji, uhlelo oluchazwe ku-kwelashwa ngokucwilisa nge-methylene blue nangokwelapha ithangi. Inani lika-mg ngelitha emanzini okucwiliswa kuwo alinakuguqulwa libe yinani lika-mg nge-kg elifakwa ngomthambo ethole, futhi inqubo yethole ayinakuhlanjululwa ukuze isetshenziswe ethangini.

Izilwane ezikhiqiza ukudla zengeza isinqumo esiphathelene nemithetho

Ayikho ilebula evamile yekhambi lobuthi le-methylene blue lezinkomo, izimvu noma izimbuzi egunyazwe yi-FDA. I-FDA ibala i-methylene blue yalezi zinhlobo njengesithako esiyinqwaba esiphakanyiselwe amakhambi obuthi ezilwane ezikhiqiza ukudla, esisacubungulwa njengamanje (ikhasi le-FDA lokuhlanganiswa kwezidakamizwa), okuyisikhundla emgqeni wokucubungulwa, hhayi ukugunyazwa futhi hhayi isikhathi sokulinda ngaphambi kokusebenzisa imikhiqizo yesilwane.

Ngakho e-United States ukusetshenziswa kwaso kwenziwa ngodokotela wezilwane ngaphansi kwezinhlinzeko zokusebenzisa umuthi ngaphandle kwemigomo yelebula. I-Animal Medicinal Drug Use Clarification Act idinga ubudlelwano obuvumelekile phakathi kukadokotela wezilwane, umnikazi nesilwane eselashwayo, kanti ezilwaneni ezikhiqiza ukudla idinga isikhathi sokulinda eseluliwe esisekelwe ngokwesayensi, kanye nokuhlonzwa kwesilwane nezindlela zokuvikela ezinsaleleni zomuthi. Ucwaningo lwamuva ngezinsalela zomuthi ezinkomeni eziyisishiyagalombili eziphilile ezanikezwa u-6 mg/kg we-methylene blue ehlanganisiwe ngomthambo lwabala izikhathi ezithathwe kulolo cwaningo zezinsuku ezingu-5 zobisi nezinsuku ezingu-6 zenyama (ucwaningo ngokuhamba komuthi emzimbeni wezinkomo nangesikhathi sokulinda). Lawo manani angawalolo hlelo locwaningo. Awasona isikhathi sokulinda esigunyazwe yi-FDA, futhi izeluleko zamanje ngezinsalela zomuthi esilwaneni eselashiwe kufanele zitholakale ngodokotela wezilwane oselaphayo nemithombo efana ne-FARAD.

Imithetho yaseYurophu iqinile kakhulu ezingeni lesithako. Izithako ezisebenzayo ngokwemithi ezisetshenziselwa izinhlobo ezikhiqiza ukudla ngokuvamile zidinga ukufakwa ohlwini lomkhawulo omkhulu wezinsalela noma ukuhlukaniswa okufanayo ngaphansi kohlaka lwe-EU lwezinsalela (isiqondiso se-EMA ngezinsalela), futhi ukuhlolwa kwe-EU kuye kwakhuluma nge-methylene blue phakathi kwezithako ezingabhaliselwe ukusetshenziswa ezilwaneni ezikhiqiza ukudla. Yichaze njengengagunyaziwe ukusetshenziswa okuvamile ezilwaneni ezikhiqiza ukudla e-EU kunokuba usungule isigaba sokwenqatshelwa. Amahhashi anesimo sokuba sengxenyeni yochungechunge lokudla adinga ukuhlolwa okufanayo ngaphambi kwanoma yikuphi ukusetshenziswa ngaphansi kohlelo lwe-cascade.

Ukulandelana okufushane kwezinqumo zikadokotela wezilwane oselaphayo

Qinisekisa i-methemoglobinemia futhi ufune isithako esibangela i-oxidation ngesikhathi esifanayo: igazi elinsundu kanye nokushintsha kolwelwesi, ukushaya kwenhliziyo ngokushesha nokuphefumula kanzima kukhomba lesi simo, kanti ukuhlolwa kwe-nitrate ku-plasma noma oketshezini lweso, kwefolishi nokwamanzi kukhomba umthombo. Susa ukuchayeka kuqala, ngoba i-methylene blue enikezwa ngesikhathi ukumuncwa ku-rumen kuqhubeka yelapha uphawu kuyilapho i-rumen iqhubeka ikhiqiza imbangela. Khetha uhlaka lohlobo lwesilwane ngaphambi kwenani: amahhashi awakwazi ukuboleka ububanzi obuyisethenjwa be-methylene blue bezilwane ezetshisayo, amakati adinga ukuqapha okukhulu kakhulu nge-oxidation, kanti izinhlanzi zidinga ukulungiswa kwamanzi kusetshenziswa indlela yokucwilisa echazwe ku-kusetshenziswa nemikhawulo ekufuyweni kwezilwane zasemanzini. Yifake kancane ngomthambo ngokufinyelela okuphephile, qapha ukuphinde kugule nokubhujiswa kwamaseli abomvu egazi, futhi ubeke isimo sobisi nenyama ngokubhala phansi ngaphansi kwemithetho yendawo yezinsalela ngaphambi kokuba isilwane siphinde singene ochungechungeni lokudla.