labarai

Cutar Alzheimer, wanda aka fi sani da tsofaffi, ya addabi yawancin mutane.

Ɗaya daga cikin ƙalubale a cikin maganin cutar Alzheimer shi ne cewa isar da magungunan warkewa zuwa nama na kwakwalwa yana iyakance ta hanyar shingen jini-kwakwalwa. Binciken ya gano cewa duban dan tayi mai ƙarancin ƙarfi da MRI ke jagoranta na iya sake buɗe shingen jini-kwakwalwa a cikin marasa lafiya da cutar Alzheimer ko wasu cututtukan jijiyoyin jijiya, gami da cutar Parkinson, ciwace-ciwacen ƙwayar cuta, da kuma amyotrophic lateral sclerosis.

Wani ƙaramin gwaji na ƙayyadaddun ra'ayi na baya-bayan nan a Cibiyar Nazarin Neuroscience ta Rockefeller a Jami'ar West Virginia ya nuna cewa marasa lafiya da cutar Alzheimer waɗanda suka sami jiko na aducanumab tare da duban dan tayi da aka mayar da hankali ga ɗan lokaci ya buɗe shingen kwakwalwar jini na ɗan lokaci ya rage nauyin amyloid beta (Aβ) na kwakwalwa a gefen gwaji. Binciken na iya buɗe sabbin kofofin zuwa jiyya don rashin lafiyar kwakwalwa.

Katangar kwakwalwar jini tana kare kwakwalwa daga abubuwa masu cutarwa yayin da ke barin mahimman abubuwan gina jiki su wuce. Amma shingen jini-kwakwalwa kuma yana hana isar da magungunan warkewa zuwa kwakwalwa, ƙalubalen da ke da zafi musamman lokacin da ake magance cutar Alzheimer. Yayin da duniya ke da shekaru, yawan masu fama da cutar Alzheimer na karuwa a kowace shekara, kuma hanyoyin magance su ba su da iyaka, suna sanya nauyi mai nauyi a kan kiwon lafiya. Aducanumab shine amyloid beta (Aβ) -wanda ke daure monoclonal antibody wanda Hukumar Abinci da Magunguna ta Amurka (FDA) ta amince da ita don maganin cutar Alzheimer, amma shigarsa na shingen kwakwalwar jini yana da iyaka.

Duban dan tayi mai da hankali yana samar da raƙuman inji waɗanda ke haifar da oscillations tsakanin matsawa da dilution. Lokacin allurar cikin jini da fallasa zuwa filin ultrasonic, kumfa suna damfara da fadada fiye da nama da jini da ke kewaye. Wadannan oscillations suna haifar da damuwa na inji akan bangon tashar jini, yana haifar da matsananciyar haɗin kai tsakanin ƙwayoyin endothelial don shimfiɗawa da buɗewa (Hoto a ƙasa). A sakamakon haka, amincin shingen jini-kwakwalwa ya lalace, yana barin ƙwayoyin cuta su yaɗu cikin kwakwalwa. Katangar kwakwalwar jini tana warkewa da kanta cikin kimanin awanni shida.

Hoton yana nuna tasirin duban dan tayi akan bangon capillary lokacin da kumfa masu girman micrometer ke kasancewa a cikin tasoshin jini. Saboda babban matsawa na iskar gas, kumfa suna yin kwangila kuma suna fadada fiye da naman da ke kewaye da su, suna haifar da damuwa na inji akan sel endothelial. Wannan tsari yana haifar da buɗewar haɗin gwiwa kuma yana iya haifar da ƙarshen astrocyte don fadowa daga bangon tashar jini, yana lalata amincin shingen jini-kwakwalwa da haɓaka yaduwar rigakafin mutum. Bugu da kari, endothelial Kwayoyin fallasa zuwa mayar da hankali duban dan tayi inganta su aiki vacuolar kai ayyukan da suppressed efflux famfo aikin, game da shi rage kwakwalwa ta yarda da antibodies. Hoto B yana nuna jadawalin jiyya, wanda ya haɗa da ƙididdigar ƙididdiga (CT) da kuma hoton maganadisu na maganadisu (MRI) don haɓaka tsarin maganin duban dan tayi, 18F-flubitaban positron emission tomography (PET) a tushe, jiko na rigakafi kafin mayar da hankali ga maganin duban dan tayi da jiko na microvesicular yayin jiyya, da kuma kula da sauti na microvesicular watsawa siginar amfani da duban dan tayi. Hotunan da aka samu bayan mayar da hankali ga duban dan tayi sun hada da T1-nau'i-nau'i-nau'i-nau'i mai girma MRI, wanda ya nuna cewa jini-kwakwalwa shamaki a bude a cikin duban dan tayi da aka yi magani yankin. Hotunan yanki guda bayan sa'o'i 24 zuwa 48 na kulawa da duban dan tayi sun nuna cikakkiyar waraka daga shingen kwakwalwar jini. Wani 18F-flubitaban PET scan a lokacin biyo baya a cikin ɗaya daga cikin marasa lafiya 26 makonni daga baya ya nuna raguwar matakan Aβ a cikin kwakwalwa bayan jiyya. Hoto C yana nuna saitin duban dan tayi mai jagorar MRI yayin jiyya. Kwalkwali transducer hemispherical yana ƙunshe da tushen duban dan tayi sama da 1,000 waɗanda ke haɗuwa zuwa wuri guda ɗaya a cikin kwakwalwa ta amfani da jagora na ainihin lokaci daga MRI.

A cikin 2001, an fara nuna duban dan tayi mai da hankali don haifar da buɗe shingen jini-kwakwalwa a cikin nazarin dabbobi, kuma binciken da ya biyo baya ya nuna cewa duban dan tayi na iya haɓaka isar da magunguna da inganci. Tun daga wannan lokacin, an gano cewa duban dan tayi mai da hankali zai iya buɗe shingen kwakwalwar jini cikin aminci a cikin marasa lafiya masu cutar Alzheimer waɗanda ba sa karɓar magani, kuma yana iya isar da ƙwayoyin rigakafi zuwa ƙwayoyin cutar kansar nono.

Tsarin isar da microbubble

Microbubbles ne mai duban dan tayi bambanci wakili wanda yawanci amfani da su lura da jini ya kwarara da jini a cikin duban dan tayi ganewar asali. A lokacin maganin duban dan tayi, an yi allurar dakatar da octafluoropropane mai rufaffen phospholipid wanda ba shi da pyrogenic. Microbubbles sun tarwatse sosai, tare da diamita daga ƙasa da μm zuwa fiye da μm 10. Octafluoropropane iskar gas ce mai tsayayye wacce ba a daidaita ta kuma ana iya fitar da ita ta huhu. Harsashi mai lipid wanda ke nannade da daidaita kumfa yana kunshe da lebobin dan adam guda uku na halitta wadanda aka daidaita su ta irin wannan hanyar zuwa phospholipids na endogenous.

Generation na mayar da hankali duban dan tayi

Mai da hankali duban dan tayi yana samuwa ta hanyar kwalkwali transducer hemispherical wanda ke kewaye da kan mara lafiya (Hoto 1C). Kwalkwali yana sanye da maɓuɓɓugan duban dan tayi na 1024 masu zaman kansu, waɗanda aka fi mayar da hankali a zahiri a tsakiyar ɓangarorin. Waɗannan hanyoyin duban dan tayi ana yin su ta hanyar mitar rediyo na sinusoidal kuma suna fitar da raƙuman ruwa na ultrasonic ta hanyar hoton maganadisu. Mai haƙuri yana sanye da kwalkwali kuma ruwan da aka cire yana kewayawa a kai don sauƙaƙe watsawar duban dan tayi. Duban dan tayi yana tafiya ta cikin fata da kwanyar zuwa makasudin kwakwalwa.

Canje-canje a cikin kaurin kwanyar da yawa zai shafi yaduwa na duban dan tayi, wanda zai haifar da ɗan lokaci daban-daban don duban dan tayi don isa ga rauni. Ana iya gyara wannan murɗaɗɗen ta hanyar samun ƙididdiga masu ƙididdiga masu ƙima don samun bayanai game da siffar kwanyar, kauri, da yawa. Samfurin kwaikwaiyo na kwamfuta na iya ƙididdige canjin lokaci da aka biya na kowane siginar tuƙi don mayar da hankali mai kaifi. Ta hanyar sarrafa lokaci na siginar RF, duban dan tayi na iya zama mai mai da hankali ta hanyar lantarki kuma a sanya shi don rufe adadi mai yawa na nama ba tare da motsa tsarin tushen duban dan tayi ba. Ana ƙayyade wurin wurin abin da aka yi niyya ta hanyar hoton maganadisu na kai yayin sanye da kwalkwali. Ƙarfin da aka yi niyya yana cike da grid mai girma uku na makin anga na ultrasonic, wanda ke fitar da raƙuman ruwa na ultrasonic a kowane wurin anga na 5-10 ms, ana maimaita kowane sakan 3. Ƙarfin ultrasonic yana ƙaruwa a hankali har sai an gano siginar kumfa da ake so, sa'an nan kuma riƙe don 120 seconds. Ana maimaita wannan tsari akan wasu raga har sai an rufe ƙarar manufa gaba ɗaya.

Bude shingen kwakwalwar jini yana buƙatar girman raƙuman sauti don wuce ƙayyadaddun kofa, wanda ya wuce abin da ke tattare da shinge yana ƙaruwa tare da karuwa mai girma har sai lalacewar nama ya faru, wanda aka bayyana a matsayin erythrocyte exosmosis, zubar jini, apoptosis, da necrosis, duk waɗannan sau da yawa suna hade da rushewar kumfa (wanda ake kira cavitation inertial). Ƙofar ya dogara da girman microbubble da kayan harsashi. Ta hanyar ganowa da fassarar siginar ultrasonic da aka warwatse ta microbubbles, ana iya kiyaye bayyanarwa a cikin kewayon aminci.

Bayan maganin duban dan tayi, an yi amfani da MRI mai nauyin T1 tare da ma'anar bambanci don sanin ko an buɗe shingen kwakwalwar jini a wurin da aka yi niyya, kuma an yi amfani da hotuna masu nauyin T2 don tabbatar da ko zubar da jini ko zubar da jini ya faru. Waɗannan abubuwan lura suna ba da jagora don daidaita wasu jiyya, idan ya cancanta.

Kimantawa da tsammanin tasirin warkewa

Masu bincike sun ƙididdige tasirin jiyya a kan nauyin Aβ na kwakwalwa ta hanyar kwatanta 18F-flubitaban positron emission tomography kafin da kuma bayan jiyya don tantance bambanci a cikin girman Aβ tsakanin yankin da aka bi da shi da kuma wani yanki mai kama a gefe guda. Binciken da aka yi a baya na wannan ƙungiyar ya nuna cewa kawai mayar da hankali ga duban dan tayi na iya rage matakan Aβ kadan. Ragewar da aka samu a wannan gwaji ya ma fi na binciken da aka yi a baya.

A nan gaba, fadada jiyya zuwa bangarorin biyu na kwakwalwa zai zama mahimmanci don kimanta ingancinsa wajen jinkirta ci gaban cututtuka. Bugu da ƙari, ana buƙatar ƙarin bincike don ƙayyade aminci da inganci na dogon lokaci, kuma kayan aikin warkewa masu tsada waɗanda ba su dogara da jagorar MRI na kan layi ba dole ne a haɓaka don samun fa'ida. Duk da haka, binciken ya haifar da kyakkyawan fata cewa jiyya da magungunan da ke bayyana Aβ na iya rage ci gaban Alzheimer a ƙarshe.