Ubururu bwa metilene mu burozwe bwa nitrati na nitriti mu matungo manini

Umukumbi ujyanwa kurisha amasaka yazahajwe n'amapfa nyuma ya saa sita. Bigeze nimugoroba, inka nyinshi zisigara inyuma, zihumeka vuba, zifite ibice bitwikiriye imyanya y'umubiri byijimye n'amaraso y'ikigina igihe bayafatiye mu mutsi. Amafarashi ari mu rwuri ruhana imbibi na rwo asa n'aho nta cyo yabaye. Iryo tandukaniro si amahirwe. Rituruka ku hantu nitrati ihindukira nitriti, kandi aho hantu ni ho hagena uko ikibazo gisuzumwa n'uko hategurwa umuti urwanya uburozi.

Ingingo y'ingenzi iroroshye: nitrati ahanini ni intangiriro y'ihinduka, nitriti ni yo burozi, kandi ubururu bwa metilene buhabwa inka zahuye na nitrati bukemura ingaruka za nitriti kuri hemoglobine. Ibindi byose biri muri iyi nyandiko bishingira kuri izo ntambwe eshatu.

Nitrati ihinduka nitriti imbere mu nyamaswa

Nitrati iri mu bwatsi ubwayo ifite ubushobozi buke bwo gutera okisidasiyo. Mikorobe zo mu gifu cya mbere ziyihindura mu byiciro bibiri: mbere na mbere nitrati ihinduka nitriti, hanyuma nitriti igahinduka amoniya. Iyo nitrati nyinshi igeze icyarimwe, icyiciro cya mbere cyihuta kurusha icya kabiri. Nitriti iriyongera, ikinjira mu maraso, igatera okisidasiyo ku cyuma kiri muri hemoglobine, ikagihindura kiva mu mimerere ya ferrous itwara ogisijeni kikajya mu mimerere ya ferric. Icyo bivamo ni methemoglobine, idashobora gutwara ogisijeni.

Inyandiko ya MSD Veterinary Manual ku burozwe bwa nitrati na nitriti igereranya ko nitriti ifite uburozi bukubye hafi inshuro icumi ubwa nitrati, kandi isobanura urwo ruhererekane rw'ihinduka. Inkomoko zisanzwe ni ibimera biribwa n'amatungo bibika nitrati, nka oats, uburo, ryegrass, ibigori, ibihwagari n'amasaka; ibyatsi bibi nka pigweed, lambsquarter, kochia n'ubwatsi bwa Johnson; kurya ifumbire; ndetse n'ibidendezi cyangwa amariba magufi yandujwe n'amazi atemba ava ku butaka. Amapfa, gukoresha ifumbire ya azote nyinshi no guhagarara kw'imikurire nyuma y'ibihe by'ibicu cyangwa ubukonje byongera nitrati mu bwatsi.

Ijanisha rya methemoglobine ntirihura neza buri gihe n'uburemere bw'ikibazo, ariko isano bifitanye ifasha kumenya izigomba kwitabwaho mbere. MSD ishyira ibimenyetso bya mbere, nk'umutima utera vuba, intege nke, gutengurwa no kudahuza imigendere, hafi ya methemoglobine iri kuri 30 kugeza kuri 40 ku ijana; guhumeka bigoranye cyane hamwe n'ibice bitwikiriye imyanya y'umubiri by'ikigina cyangwa by'ubururu bikagaragara hejuru ya hafi 50 ku ijana; naho urupfu rukaba rukunze kubaho kuri 80 ku ijana cyangwa hejuru. Amaraso y'ikigina gisa na shokola, akomeza kuba ikigina iyo ageze mu kirere, ni ikimenyetso kiranga iki kibazo ariko nticyihariye kuri cyo gusa. Methemoglobine kandi isubira uko yari iri vuba bihagije ku buryo ingero zafashwe zitinze zigaragaza agaciro kari munsi y'urugero rwo hejuru rwari rwagezweho. Kugira ngo byemezwe, MSD ihitamo gupima nitrati muri plasma mbere y'urupfu, no mu matembabuzi yo mu jisho nyuma yarwo, hakiyongeraho isesengura ry'ubwatsi n'amazi. Indangagaciro zirenga hafi 20 ppm za nitrati cyangwa 0.5 ppm za nitriti mu ngero zikwiye zafashwe mu mubiri akenshi zerekana ko inyamaswa yahuye n'ingano ikabije.

Uko ubururu bwa metilene bukuraho iyo nzitizi

Mu mimerere isanzwe, methemoglobine nyinshi isubizwa uko yari iri n'uburyo bukoresha NADH na cytochrome b5 reductase. Ubururu bwa metilene bwifashisha inzira ya kabiri, isanzwe igira uruhare ruto. NADPH yo mu turemangingo, ikorwa binyuze mu nzira ya pentose phosphate, itanga elegitoroni zinyura muri reductase ikenera NADPH zikagera ku bururu bwa metilene, zikabuhindura leucomethylene blue. Iyi na yo isubiza icyuma cya ferric mu mimerere ya ferrous muri hemoglobine. Inyandiko ya StatPearls ku buryo ibi bikorwa isobanura uru ruhare rwo gutwara elegitoroni.

Iyo mikorere ya shimi ni yo kandi itera impamvu nyamukuru yo kwitonda. Ubururu bwa metilene ni umuti ukora mu guhererekanya elegitoroni, si umuti urwanya okisidasiyo gusa. Iyo ubwinshi bwawo buri hejuru, ubwawo butera okisidasiyo, bukongera gukora methemoglobine kandi bukangiza uturemangingo dutukura tw'amaraso. Ni yo mpamvu kutabona impinduka nziza bikwiye gutuma umuganga w'amatungo yongera gusuzuma niba ikibazo cyamenyekanye neza, niba nitriti ikomeje kwinjira mu maraso ivuye mu gifu cya mbere, n'imiterere y'uturemangingo dutukura tw'amaraso, aho gukomeza gutanga ingano nini kurushaho gusa. Uburyo rusange bukoreshwa mu bitaro, harimo gusuzumisha co-oximetry no gutera umuti hakurikiranwa n'umuganga, busobanurwa mu nyandiko ubururu bwa metilene kuri methemoglobinemia.

Kugereranya amoko n'uko ahura n'uburozi

Iyi mbonerahamwe ifasha mu gufata icyemezo. Buri murongo uhuza inzira uburozi bwinjiramo, aho ihinduka ribera, n'ibyo ubururu bwa metilene bushobora gukora n'ibyo budashobora gukora.

Inyamaswa zuza: inka, intama n'ihene

Inka ni zo zikunze kwibasirwa cyane, kandi inyandiko zigenewe gufasha aborozi zikunze kuzishyira ku mwanya wa mbere mu matungo yoroshye kwibasirwa. Intama n'ihene na zo ziribasirwa, ariko akenshi zivugwa ko zigirwaho ingaruka nke ugereranyije, bishoboka ko biterwa n'uko zitunganya nitrati nyinshi vuba kurushaho. Uru rutonde rukwiye gufatwa nk'icyerekezo gifasha, aho kurufata nk'itegeko rya biyoshimi ryamaze kwemezwa burundu.

Gutakaza ibyari guturuka ku kororoka bikwiye kwitabwaho ukwabyo. Inka zirokotse methemoglobinemia ikomeye yamaze igihe kirekire zishobora gukuramo inda cyangwa kubyara inyana zapfuye nyuma y'iminsi hafi 5 kugeza kuri 14, ibyo bikaba bihuye no kubura ogisijeni kw'inda. Inyana imeze neza mu gitondo gikurikiyeho ntihamya ko uburozi bwari buke, kandi gukuramo inda nyuma y'icyumweru ntibihamya ko habayeho kongera guhura n'uburozi.

Ingano z'ubururu bwa metilene zigenewe inka zivugwa mu nyandiko zasohotse ntizihura, kuko zituruka ku bwoko butandukanye bw'ibimenyetso by'ubushakashatsi. Inyandiko iriho ubu ya MSD ivuga 4 kugeza kuri 15 mg/kg cyangwa kurenga zitangwa buhoro mu mutsi, zivuye mu muti ushonga uri kuri 1 kugeza kuri 2 ku ijana. Ingano no gusubiramo bigenwa n'uburemere bw'ikibazo n'uburozi bukomeza kwinjira mu maraso, kandi ivuga yeruye ko inyamaswa zuza ari zo zonyine zihanganira ingano zo hejuru mu buryo butekanye. Hiyongeraho ubushakashatsi buto na raporo zo mu bworozi: ubushakashatsi bwa kera ku nka bwasanze 1 mg/kg ihagije mu mimerere yabwo; ubushakashatsi ku mikorere y'umuti mu ntama bwasuzumye 15 mg/kg zitangwa mu mutsi; ubushakashatsi ku ihene bwagerageje 1 kugeza kuri 4 mg/kg, amatsinda yahawe 4 mg/kg akagira ibisubizo byiza kurusha ayandi; naho raporo zo mu bworozi zivuga gukira hafi kuri 4 mg/kg, ndetse n'urugero rudasanzwe rw'inka yahawe hafi 20 mg/kg. Ubushakashatsi bwo mu 1984 ku rugendo rw'umuti mu mubiri w'intama bugaragaza neza iki cyiciro: bufasha gutekereza ku bushobozi bwo kwihanganira umuti, ntibutanga amabwiriza yemewe yo ku kirango.

Mu byemezo by'ubuvuzi bw'amatungo byo gukoresha ubururu bwa metilene kuri methemoglobinemia mu ntama, isomo rifatika ni uko nta mubare umwe ukwiriye buri kibazo. Gukomeza gukorwa kwa nitriti mu gifu cya mbere bivuga ko inyamaswa yatangiye gukira ishobora kongera kuremba uko indi nitriti yinjira mu maraso. Ni yo mpamvu MSD ihuza gusubiramo umuti n'uburozi bukomeje kwinjira, aho kubishingira kuri gahunda idahinduka. Ubuvuzi bwo gufasha inyamaswa bukorerwa hamwe n'ibi: kuyifata mu buryo butayitera umunaniro kugira ngo hagabanuke ogisijeni ikenera, kuyikura ku biryo n'amazi bikekwa, kuyisimburiza ibiryo bitekanye, no kwita ku maraso agera mu ngingo. Ubururu bwa metilene butangwa mu nshinge burakaza aho bwatewe, bityo kwemeza ko inzira yo mu mutsi imeze neza no gutanga umuti buhoro mu mutsi ni ngombwa. Guhinduka kw'ibara ry'ingingo, inkari n'ibyuma byumva ibipimwa na byo bikwiye kwitegwa. Imipaka ku marangi n'imiti iterwa hanze mu buvuzi bw'amatungo ishyira mu murongo mugari inzitizi zishingiye ku moko.

Amafarashi ni ikibazo cyihariye

Mu mafarashi, isya ry'ibintu birimo fibre rikorerwa mu gice cy'inyuma cy'amara aho kuba mu gifu cya mbere. Mikorobe zo mu mara y'impumyi zishobora guhindura nitrati, ariko irihinduka ni nke cyane ugereranyije no mu nka, bityo amafarashi akuze muri rusange ntibasirwa na nitrati yo mu bwatsi nk'inka. Nitriti yari isanzwe yarakozwe inyura kuri ubwo burinzi, igakomeza kuba akaga.

Uburyo bwo guhitamo umuti urwanya uburozi na bwo burahinduka. Mu bushakashatsi bwa kera bwagereranyaga igenzurwa rya methemoglobine mu turemangingo dutukura tw'amaraso, ubururu bwa metilene bwongereye gusubiza methemoglobine uko yari iri mu turemangingo tw'abantu, ariko ntibwabikora mu tw'amafarashi (ubushakashatsi ku turemangingo dutukura tw'amaraso y'amafarashi). Inyandiko ku burozi mu mafarashi na zo zisobanura ukwazo ko ubururu bwa metilene ubwabwo bushobora gutera hemolysis ijyana n'utubumbe twa Heinz n'uturemangingo twa eccentrocyte dukomoka kuri okisidasiyo. Zinaburira ku kubukoresha mu bibazo biterwa na okisidasiyo, nk'uburozi bw'igiti cya maple gitukura. Nta na kimwe muri ibi gihamya ko umuti udashobora na rimwe gufasha ifarashi runaka, ariko byombi bibuza ikosa rikunze gukorwa ryo kugabanya ingano yo muri gahunda y'inka hakurikijwe ibiro. Ifarashi ikekwa kuba ifite methemoglobinemia iterwa na nitriti ikeneye isuzuma ryayo bwite, kumenya icyateye okisidasiyo no gusuzuma ibyago, aho gukoresha imbonerahamwe y'ingano igenewe inyamaswa zuza.

Inyamaswa zo mu rugo n'amafi yo mu bigega bigaragaza impamvu kugendera ku biro gusa bidakora

Injangwe ni zo zigaragaza cyane impamvu yo kwitonda. Hemoglobine y'injangwe yoroshye cyane kwangirika mu miterere bitewe na okisidasiyo, kandi guhabwa ubururu bwa metilene bwinshi cyangwa kenshi bitera utubumbe twa Heinz na hemolysis aho kuzikiza. Imbwa ntizoroshye kwangirika nk'injangwe, ariko na zo zishyirwa mu moko yibasirwa mu bushakashatsi bugereranya amoko. Ibintu bitera okisidasiyo inyamaswa zo mu rugo zihura na byo biratandukanye, kuko akenshi biba ari imiti, ibinyabutabire n'ibintu zamize, aho kuba nitrati yo mu rwuri.

Mu mafi, uburyo ikibazo kibamo buratandukanye rwose. Nitriti yinjirira mu myanya y'ubuhumekero, bityo igikwiye guhindurwa mbere y'umuti uwo ari wo wose ni imiterere ya shimi y'amazi, cyane cyane ihiganwa rya chloride no gukuramo nitriti. Ubururu bwa metilene ku mafi butangwa hakurikijwe ubwinshi bwabwo mu mazi amafi ashyirwamo, hitawe ku bwoko, igihe amara muri ayo mazi, ubushyuhe n'ingaruka ku kayunguruzo gakoresha mikorobe. Ubu buryo busobanurwa mu nyandiko kuvura hakoreshejwe ubururu bwa metilene mu mazi yihariye no mu kigega. Agaciro ka mg kuri litiro mu mazi inyamaswa ishyirwamo ntigashobora guhindurwa ngo kabe mg kuri kg zitangwa mu mutsi w'inyana, kandi gahunda y'inyana ntishobora kuvangwa n'amazi menshi ngo ikoreshwe mu kigega cy'amafi.

Amatungo atanga ibiribwa asaba n'icyemezo gishingiye ku mategeko

Nta kirango gisanzwe cy'umuti urwanya uburozi w'ubururu bwa metilene cyemewe na FDA ku nka, intama cyangwa ihene. FDA ishyira ubururu bwa metilene kuri aya moko mu bintu by'ibanze bisabwa kwemerwa mu gutegura imiti irwanya uburozi ku matungo atanga ibiribwa, bikiri gusuzumwa (urupapuro rwa FDA ku gutegura imiti ivanzwe). Uwo ni umwanya ku rutonde rwo gusuzumwa, si ukwemerwa kandi si igihe cyo gutegereza mbere yo gukoresha ibikomoka ku matungo nk'ibiribwa.

Muri Leta Zunze Ubumwe za Amerika, ikoreshwa ryawo rero rigomba kunyura ku muganga w'amatungo hakurikijwe ingingo zemerera gukoresha umuti bitandukanye n'ibiri ku kirango. Itegeko risobanura ikoreshwa ry'imiti mu matungo risaba umubano wemewe hagati y'umuganga w'amatungo, umukiriya n'inyamaswa ivurwa. Ku matungo atanga ibiribwa, risaba kandi igihe cyagutse cyo gutegereza gishyigikiwe n'ubushakashatsi, hamwe no kumenya amatungo yavuwe no gushyiraho ingamba zo kwirinda ibisigazwa by'umuti. Ubushakashatsi bwa vuba ku bisigazwa by'umuti mu nka umunani zifite ubuzima bwiza zahawe mu mutsi 6 mg/kg z'ubururu bwa metilene bwateguwe buvanze bwabaze ibihe bishingiye kuri ubwo bushakashatsi: iminsi 5 ku mata n'iminsi 6 ku nyama (ubushakashatsi ku rugendo rw'umuti mu mubiri w'inka no ku gihe cyo gutegereza). Iyo mibare ireba imiterere y'ubwo bushakashatsi. Si igihe cyo gutegereza cyemewe na FDA, kandi inama zigezweho ku bisigazwa by'umuti mu nyamaswa yavuwe zikwiye gutangwa n'umuganga uyikurikirana, yifashishije amasoko nka FARAD.

Amategeko y'i Burayi arakaze kurushaho ku rwego rw'ikinyabutabire ubwacyo. Ibinyabutabire bifite ibikorwa by'umuti ku moko atanga ibiribwa muri rusange bikenera gushyirwa ku rutonde rugaragaza urugero ntarengwa rw'ibisigazwa byemewe, cyangwa gushyirwa mu cyiciro kingana na byo mu mategeko y'Umuryango w'Ubumwe bw'u Burayi ku bisigazwa (amabwiriza ya EMA ku bisigazwa). Isuzuma ry'uwo muryango ryavuze ubururu bwa metilene mu bintu bitanditswe ngo byemererwe gukoreshwa ku matungo atanga ibiribwa. Bukwiye kuvugwa nk'ubutemerewe gukoreshwa bisanzwe ku matungo atanga ibiribwa muri uwo muryango, aho guhimba icyiciro cy'ibibujijwe. Amafarashi ari mu matungo ashobora gutanga ibiribwa akenera iryo genzura na yo mbere yo gukoresha umuti hakurikijwe uruhererekane rw'amahitamo yemerewe n'amategeko.

Urukurikirane rugufi rw'ibyemezo ku muganga w'amatungo ukurikirana ikibazo

Emeza methemoglobinemia kandi ushake icyateye okisidasiyo icyarimwe: amaraso y'ikigina hamwe n'impinduka ku bice bitwikiriye imyanya y'umubiri, umutima utera vuba no guhumeka bigoranye birayerekeza; naho gupima nitrati muri plasma cyangwa mu matembabuzi yo mu jisho, hamwe no gupima ubwatsi n'amazi, bikerekeza ku nkomoko. Banza ukureho uko inyamaswa ihura n'uburozi, kuko ubururu bwa metilene butangwa igihe nitriti ikomeje kwinjira mu maraso ivuye mu gifu cya mbere bukemura ikimenyetso mu gihe igifu cya mbere gikomeza gukora impamvu yacyo. Hitamo uburyo bujyanye n'ubwoko mbere yo guhitamo ingano: amafarashi ntashobora kwifashisha urugero rushingirwaho rw'ubururu bwa metilene rw'inyamaswa zuza; ku njangwe hakenewe kwitonda cyane kurusha izindi ku ngaruka za okisidasiyo; naho amafi akenera gukosora imiterere y'amazi hakurikijwe uburyo bwo kuyashyira mu mazi arimo umuti, buvugwa mu nyandiko ikoreshwa n'inzitizi mu bworozi bw'ibinyabuzima byo mu mazi. Tanga umuti buhoro mu mutsi ufite inzira yizewe, ukurikirane kongera kuremba na hemolysis, kandi wandike uko amata n'inyama bizakoreshwa hakurikijwe amategeko y'aho uri ku bisigazwa by'imiti, mbere y'uko inyamaswa yongera kwinjira mu ruhererekane rw'ibiribwa.