We thank John Olsen (Wisconsin Department of Natural Resources), Tom Cooley, Daniel O'Brien and Steve Schmitt (Michigan Department of Natural Resources) and Dr. Daniel Walsh (USGS National Wildlife Health Center) for assistance with tissue acquisition. We also thank the Wisconsin State Laboratory of Hygiene for diagnostic testing services, and Dr. Tonie Rocke and her staff (USGS National Wildlife Health Center) for use of equipment. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

USGS Ulusal Yaban Hayatı Sağlığı Merkezi&#39;nde gerçekleştirilen Hayvan çalışmaları Laboratuar Hayvan Refahı kurallar NIH Ofisi uyarınca ve kurumsal hayvan bakımı ve kullanımı komitesi protokol # EP080716 altında yapıldı. Avcı-hasat hayvanlardan dokular Wisconsin veya Doğal Kaynaklar Michigan Müdürlüklerinden hediye edildi. 1. Çözüm hazırlanması Not: Aşağıda listelenen çözümler aşağıda Bölüm 2 CER deney alt-tabakanın hazırlanması için gereklidir. Daha yüksek konsantrasyonu, stok çözeltilerinden, bu çözümlerin her birinin hazırlanması; stok çözeltileri için tavsiye edilen konsantrasyon listelenen her biri ilgili kimyasal tanımlamanın sonra parantez içinde verilmektedir. Kullanılana kadar 4 ° C&#39;de Yüzey hazırlığı ve mağaza üzerine taze tüm çözümleri hazırlayın. <ol><li> 100 mM s: liziz tamponu için, 10 mM Tris içinde, pH 7.5 (1M Tris, pH 7.5 stok çözeltisi tavsiye edilir) aşağıdaki içeren bir çözelti hazırlamakde sodyum klorid (NaCI, 1 M stok çözelti), 10 mM etilendiamintetraasetik asit (EDTA, 500 mM EDTA, pH 8.0 stok çözelti),% 0.5 NP-40 (% 10 stok çözelti),% 0.5 deoksikolat (DOC,% 10 stok çözeltisi ). </li><li> Dönüşüm tamponu sağlamak için,% 0.05 sodyum dodesil sülfat (SDS,% 10 stok çözelti) ve% 0.5 Triton X-100 1, fosfat tamponlu tuzlu su içinde (% 10 stok çözelti) (PBS, 10, pH 7.4 stok çözelti) ihtiva eden bir çözelti hazırlayın. </li><li> Chaotropic çözümler için, guanidinhidroklorid 1x PBS (GdnHCl, 8 M stok) (10x stok çözelti) iki 3 M çözüm hazırlamak. Konsantre edilmiş hidroklorik asit (HCl) ile 3.5 ± 0.05&#39;e çözümlerden biri pH ayarlayın. İkinci çözeltinin pH değeri pH 7,4 ± 0,05 kalmasını kontrol edin ve konsantre HCI veya sodyum hidroksit (NaOH), gerekirse kullanarak ayarlayın. </li></ol> 2. CER Testi Yüzey Çiftleri hazırlayın <ol><li> Ilgi türlerin sağlıklı olmayan TSE-enfekte beyin dokusu elde edilir ve% 10 ağırlık başına hacim hazırlamakAşağıdaki yöntemlerden herhangi biri kullanılarak parçalama tamponu içinde homojenatı (ağ / hac): Dounce, boncuk değirmeni veya havan ve dibek homojen hale getirilmesi. Ayrıca, şırınga-ve-iğne homojenizasyon onları tabi tabaka aspire ve 27 G şırınga iğne ile kolaylıkla sınırdışı edilebilir kadar artan göstergesi iğneler kullanarak homojenatları ortaya çıkan rafine. <ol><li> Kemirgenler ve diğer küçük memeliler hazırlanan yüzeyler için, bütün beyin (ler) homojenize; Daha büyük memeliler hazırlanan yüzeyler için, homojenatları hazırlamak için obex (beyin sapı) doku kullanın. Beyin homojenatının miktarını seçerken, Aşama 2.6 protein çökelmesi için kullanılan santrifüj kapasitesinin en fazla% 50 hazırlar. </li><li> Edinilmiş beyin dokusunun kalitesi sorgulanabilir ise, SDS-PAGE 16 ve immunoblot 17 alt tabakaya önce hazırlık PrP ​​C düzeylerini değerlendirmek. </li></ol></li><li> Ayrı etiketli plastik konik tüpler iki eşit hacimlerde içine beyin Homojenat bölün. (GdnHCl EkleBeyin homojenatı 1 hacim oranı: pH 3.5 ya da 1, her bir tüpe 7.4 ya da 1 PBS içinde 3 M solüsyonu). </li><li> Iki çözeltinin pH değeri kontrol edin. Konsantre HCI kullanılarak 0.05 ± pH, pH 3.5, substratın pH ayarlayın. Diğer alt-tabakanın pH&#39;ı, pH 7.4 ± 0.05 olarak kalmasını sağlamak ve HCI veya NaOH ile gerektiğinde gerekli olduğu yerde pH&#39;ı ayarlamak. Asit veya bir baz makul ilavesiyle pH değerleri aşılması kaçının. </li><li> 5 saat boyunca oda sıcaklığında (RT), bir ucu-üzerinde-ucunda karıştırıcı çözüm döndürün. </li><li> Her konik bir tüp içinde alt-tabaka çözeltiler metanol dört hacmi eklenerek proteinin çökeltilmesi, girdap, iyice karıştırılmakta ve 16-18 saat süre ile -20 ° C &#39;de inkübe etmek. </li><li> 4 ° C&#39;de 30 dakika boyunca 13,000 x g&#39;de santrifüj ile tortu örnekleri. Dikkatle süzün ve Süpernatantlar atmak ve metanol pelet buharlaşmasına izin verin. Tüp içine sarıldı metanol emmede yardım sağlamak için pamuk uçlu aplikatörler kullanın. Pelet over-dr izin vermeyiny ve metanol artık görünür bir kez, bir sonraki adıma geçin. </li><li> Dönüşüm tampon maddesi içinde yeniden süspanse Protein peletleri. Aşama 2.2 Her tüpe dağıtılmıştır beyin homojenatı başlangıç ​​malzemesinin miktarına eşit dönüşüm tampon bir miktar kullanın. NOT: Bu dönüşüm tampon hem de pH 3.5 ve 7.4 ile muamele edilmiş alt-tabaka preparatlar protein pelet yeniden askıya almak için (deterjan düşük seviyeleri ve fizyolojik bir pH&#39;a sahip) Yukarıdaki adım 1.2 tanımlanan bir çözelti kullanılır kritiktir. </li><li> Bir cuphorn sonikatörde Kısaca sonikasyon altyapı solüsyonları, (% 30 maksimal gücü ° &#39;de 10 sn), 0.5 içine kısım - etiketli bir 1.5 ml mikrosantrifüj tüpleri içinde, 1.0 ml hacim. Her bir alt-tabakanın bir tümbölen üzerinde bir kalite kontrol immüno (adım 2.9) yapın. CER tahlili (Bölüm 4) gerçekleştirmek için hazır olana kadar -80 ° C&#39;de diğer alikotları saklayın. </li><li> Kullanmadan önce CER substrat çiftleri (Şekil 2) kalite kontrolünü gerçekleştirin. Bu adımlar CER alt-tabakalar provid sağlamakDönüşüm çalışmalarında E en iyi sonuçlar. <ol><li> İki yüzeylerde PrP C karşılaştırılabilir miktarda olun. 10-25 SDS-PAGE 16 tarafından her alt tabakanın ul ve 17 imünolekeleme PrP seviyelerini karşılaştırın. 7.4 ve 3.5 alt-tabakalar birbirinin% 10 ~ dahilinde pH protein seviyeleri, alt-tabaka çiftlerinin CER çalışmalarda kullanım için uygun ise. NOT: PrP immünblotlarında geniş PrP C bozulma kanıt göstermek gerekir. PrP imünoreaktivite özellikle&gt; 20 kDa olmalıdır. Bu moleküler kütleye daha az Grupları bozunma ürünleri olabilir. Bantlama desen substrat çiftleri arasında kabaca eşit olmalıdır. </li><li> Her iki alt tabaka PrP Cı duyarlı PK olması gerektiği gibi, 100 ug / ml bir son konsantrasyonda PK ile her bir alt tabaka 10-25 ul tedavi ve ısı bir çalkalayıcıda 1 saat süreyle 37 ° C&#39;de 1000 rpm&#39;de örnekleri özet. SDS-PAGE 16 ve 17 imünolekeleme kalan herhangi bir sinyal PrP değerlendirin.PrP res ile Yüzeyleri CER çalışmalarında kullanılmak için uygun değildir. </li></ol></li></ol> 3. TSE Ajan tohumları hazırlayın <ol><li> Çevrede türünden TSE ile enfeksiyona uğramış beyin dokusu elde edilir ve 1 x PBS, pH 7.4 içinde homojenat yukarıdaki adım 2.1 listelenen yöntemler kullanılarak (a / h), 10% hazırlar. Not: Tohumlar aynı zamanda merkezi sinir sistemi dışındaki diğer TSE ile enfeksiyona uğramış doku elde edilebilir, bununla birlikte, TSE ile enfeksiyona uğramış periferik dokularda türetilen tohumlar ile beyin türevi substratların dönüşüm etkinliği daha deneysel yayınlanmış literatürde değerlendirilmemiştir. </li><li> 100 içine Homojenat (ler) elde edilen kısım - hazır olana kadar -80 ° C de, 0.5 ml mikrosantrifüj tüpleri içinde 300 ul hacim ve mağaza CER deneyi gerçekleştirmek için. </li></ol> 4. CER Testi Not: CER deney bir türden (&quot;tohum&quot; olarak verilen), PrP TSE nispeten küçük bir miktarının ilave edilmesini içerirkısmen pH 3.5 ya da 7.4 ya da C&#39;da denatüre edilmiş olan başka bir türden (enfekte edilmemiş beyin &quot;alt-tabaka&quot; olarak verilen), PrP ° C&#39;lik bir kıyasla, daha fazla içine. Uzun bir çalkalama enkübasyon süresinin ardından, her bir reaksiyon PrP TSE PrP C şablon odaklı dönüştürme PrP res kalan PK sindirim hem de immün algılama sonra densitometrik sinyali ile değerlendirilir. Daha önce pH değeri 3.5 vs 7.4 de denatüre yüzeylerde PrP res seviyelerini karşılaştırılması tür engeli bir ölçü sağlar. Bu deney prosedürü bir deneme genel görünüşü Şekil 1&#39;de verilmiştir. <ol><li> Yavaş yavaş bulaşmamış CER substrat çiftleri çözülme buz yatağı (yaklaşık 1 saat çözülme zamanı) üstüne yerleştirerek ve TSE-enfekte tohum çözümleri (tahlil daha önce hem pH 3.5 ve 7.4 de denatüre yüzeylerde eşit hacimlerde gerektirir). </li><li> Tamamen çözülmüş sonra, aspirat ve ardından aracılığıyla her bir taban çözüm sınırdışı27 G iğne şırınga birkaç kez yeniden homojenize. Kısaca, 30% maksimum güç ° &#39;de 10 saniye boyunca her bir TSE ile enfeksiyona uğramış tohum çözeltisi sonikasyon. Dönüşüm reaksiyonları hazırlarken buz üzerinde tüm çözümleri tutun. </li><li> TSE ajanı başına Etiket 5 ayrı düşük bağlanma, ince duvarlı PCR tüpleri test edilir. </li><li> PH 3.5 hazırlanmış, pH 7.4 ve (b) CER alt-tabaka hazırlanır: (a) CER alt-tabaka 95 ul% 10 TSE ile enfeksiyona tohum çözeltisi 5 ul ekleyerek, bu tüpler dönüşüm reaksiyonları hazırlayın. <ol><li> Her deney örneği için, önce her iki pH değeri 3.5 ve 7.4 de denatüre CER substrat çiftleri paralel reaksiyonlar hazırlamak. </li><li> Ampirik belirlenmesi yoluyla enfekte olmamış beyin yüzeye TSE ajanı tohum oranları optimize. Ortak tohum: kullanılan alt-tabaka oranları 100 ul toplam reaksiyon hacmi korumak ve 1:99 ul 2:98 ul ve 5:95 ul bulunmaktadır. Çoğu uygulama için, 5:95 ul tohumu: Yüzey hacim oranı uygun ve inci ne sunulmuştur edilirprotokoldür. </li></ol></li><li> Aşağıdaki gibi, TSE maddesi başına üç kontrol numuneleri, test edilen hazırlayın: (a) giriş PrP res için bir kontrol olarak 95 ul dönüşüm tamponu,% 10 TSE ile enfeksiyona tohum çözeltisi 5 ul; (b) pH değeri 3.5 ve non-spesifik olmayan şablonu dönüşüm için kontrol olarak (C), pH 7.4&#39;te hazırlanan 95 ul substrata 5 ul dönüşüm tampon eklemek. </li><li> Kısaca iyi tohum ve alt tabakayı karıştırmak için kapalı PCR tüpünde her örnek vorteks. PCR tüp kapağına sıkışan reaksiyon karışımının herhangi hacmi kaldırmak için düşük hızda tezgah üstü mini santrifüj bir anlık darbe ile izleyin. </li><li> PCR tüpleri kabul donanımlı bir tezgah üst termo-çalkalayıcı içine ayrı ayrı etiketli PCR tüpleri yükleyin örnekleri. 24 saat boyunca 37 ° C&#39;de 1000 rpm&#39;de örnekleri çalkalayın. </li><li> Izlenerek (ağırlık / hacim) ve FK-100 ug / ml &#39;lik bir nihai konsantrasyona kadar% 2&#39;lik bir nihai konsantrasyona kadar Sarkosyl ilave sarsma. Özet örnekleri termo-karıştırıcısı içinde 1 saat boyunca 37 ° C&#39;de 1,000 rpm&#39;de. NOT: PrP C PK sindirim örneklerin sonrası dönüşüm yardımları için Sarkosyl eklenmesi. Giremeyen numuneler (4.5 Adım) yanlış pozitif sinyaller neredeyse Sarkosyl eklenmesiyle ortadan kalkar. </li><li> 17 immunoblotting SDS-PAGE 16 her bir numune içinde Kalan PrP res 5 dakika boyunca 95 ° C&#39;ye kadar, SDS-PAGE numune tampon maddesi, ısı örnekleri ekleyin ve çözmek. Not: Örnek tampon ve ısıtma ek olarak, örnekler hemen işlenebilir veya örnekleri -20 ° C&#39;de saklandı veya -80 ° C önce immunoblotting sonra. Burada sunulan tüm veriler Novex NuPAGE jel ve transfer sistemleri kullanılarak üretildi. CER tahlilinden Tüm örnekler örnek tamponu ve üreticinin talimatlarına uygun olarak indirgeme maddesi ile muamele edilmiştir. Numuneler daha sonra 5 dakika boyunca 95 ° C&#39;de ısıtıldı ve her numune için 30 ul% 12 Bis-Tris hazır jel yüklenmiştir. </li><li> Bir tedbir olarak dönüşüm verimliliği oranı (CER) hesaplayıntür bariyer. Dansitometri 17 ile PrP res Tedbir seviyeleri ve pH 3.5 örnek olduğu pH 7.4 numunenin toplam yoğunluğunu bölmek. Bir yüzdesini üretmek için 100 ile çarpın. </li><li> Belirli bir TSE ajanı ile bir tür için ortalama CER ± standart sapma oluşturmak için bağımsız deneysel çoğaltır gelen verileri derlemek. </li></ol>

<ol>
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L., Griffith, B. J., Wishart, D. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Shaking+Alone+Induces+De+Novo+Conversion+of+Recombinant+Prion+Proteins+to+beta-Sheet+Rich+Oligomers+and+Fibrils.">Shaking Alone Induces De Novo Conversion of Recombinant Prion Proteins to beta-Sheet Rich Oligomers and Fibrils.</a> PLoS One. 9 (6), e98753 (2014).</li><li>Mathiason, C. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Susceptibility+of+domestic+cats+to+chronic+wasting+disease.">Susceptibility of domestic cats to chronic wasting disease.</a> J Virol. 87 (4), 1947-1956 (2013).</li><li>Seelig, D. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lesion+Profiling+and+Subcellular+Prion+Localization+of+Cervid+Chronic+Wasting+Disease+in+Domestic+Cats.">Lesion Profiling and Subcellular Prion Localization of Cervid Chronic Wasting Disease in Domestic Cats.</a> Vet Pathol. , (2014).</li><li>Stewart, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetic+predictions+of+prion+disease+susceptibility+in+carnivore+species+based+on+variability+of+the+prion+gene+coding+region.">Genetic predictions of prion disease susceptibility in carnivore species based on variability of the prion gene coding region.</a> PLoS One. 7 (12), e50623 (2012).</li><li>Russell, W. M., Burch, R. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The Principles of Humane Experimental Technique. Metheun. , (1959).</li></ol>

The authors have nothing to disclose.

Bu protokolün başarıyla tamamlanması için, dikkat substrat hazırlanması (adım 2.1.2) ve dönüşüm reaksiyonlarının (adım 4.4.2) için madde oranı için tohum için kullanılan bulaşmamış beyin dokusunda PrP C seviyelerine dikkat edilmelidir. Bizim tecrübelerimize göre, beyinleri sürece PrP C immunoblotting (Şekil 4) ile mevcut olduğu gibi, önemli bir dönem otopsi sonrası CER substrat olarak kullanılmak üzere elde edilebilir. Aslında, bazı otoliz CER ça...

Bulaşıcı sünger tipi ansefalopatiler (TSEler prion hastalıkları, vs.), hayvanlarda ve insanlarda çeşitli etkiler uzun kuluçka dönemleri ile ölümcül nörodejeneratif hastalıkların bir grubudur. TSElerin varsayılan etiyolojik ajan bir enfeksiyon, hastalık ile ilişkili olarak PrP ​​(PrP C) normal hücre formunun şablon odaklı dönüştürme yoluyla kendi kendine yayılma kapasitesine sahip konakçı prion proteini (PrP), bir yanlış katlanmış izomer oluşur enfekte konak 1 merkezi sinir sistemi dokularında biriken formu (PrP TSE). Bulaşıcı memeli prionların genellikle türler arası iletim olayları 2 sınırlayıcı &quot;TSE tür engeli&quot; kavramına yol açmıştır bir türe özgü bir şekilde, konak-to-host dan iletir. prion tür bariyer biyolojik belirleyicileri iyi anlaşılmış değildir. Bulaşıcı PrP TSE ve ana PrP Cı C arasında amino asit dizisi benzerliğibir kuvvetle dönüşüm 3-5 gerçekleşir, ancak in vivo 6,7 gözlenen tüm prion iletim olayları açıklamak için yetersiz kalır mı etkilemektedir. Böylece, TSE tür engellerin karakterizasyonu büyük ölçüde hayvan meydan çalışmaları güvenerek etti: diğerinden prionlara verilen bir türe naif hayvanların teşhir ve hastalığın başlangıcında ve iletim verimliliği göstergeleri olarak saldırı hızı ortaya çıkan kuluçka süresi ölçme. Insan olmayan primat, PrP C ifade eden fareler da çalışma 8, bu tür kullanılır. transgenik fare üretimi ve uzun süreli prion biyoanalizlerin yanı sıra, hayvan kullanımının etik hususlar ile ilgili maliyetler, TSE türleri engellerin deneysel soruşturma engeller vardır. TSEler insan türü bariyer değerlendirilmesi, insan PrP C ifade etmek üzere geliştirilen fareler üzerinde dayanır. Bu fareler insan TSElerinin veya t değişikliklere yenik uzun kuluçka dönemleri gerektirirhızlı hastalık başlangıcı 9 o insan PrP C molekülü. Bu farelerde insan olmayan TSEler için İnkübasyon süreleri zorlu negatif sonuçların yorumunu yapıyor normal fare ömrü ötesine uzanabilir. Sigara insan primatlar da insan türü engelleri incelenmesi için vekiller olarak kullanılmıştır, ama insan konakta ilerlerken bu çalışmalar tam hastalığı özetlemek olmayabilir hayvan deneyleri ve insan olmayan primatların diğer türleri gibi aynı sorunlarla doludur. Hayvan biyodeneyler bir TSE için bir türün hassasiyetini ölçmek için &quot;altın standart&quot; yöntemi kalır, ancak engeller, maliyetler ve bu canlı hayvan çalışmalarının etik alternatifler soruşturma mecbur var. PrP TSE tarafından seribaşı bir proteinaz K (PK) dirençli devlet (PrP res) ev sahipliği PrP C dönüşüm değerlendirilmesine dayanmaktadır in vitro tahliller, bir dizi gelişmiş ve TSE sp araştırmak için kullanılmıştırecies engelleri 10-12. In vitro tahlillerin örnekleri, hücre içermeyen dönüşüm tahlilleri, protein siklik amplifikasyon (PMCA) yanlış katlanması ve dönüşüm verimliliği oranının (CER) deney 10-14 içerir. Bu testlerin hiçbiri doğal enfeksiyondan sonra tür engelleri katılan hesap periferik faktörler içine alırken, tüm TSEler için potansiyel duyarlı ana belirlemek için yararlı olabilir. Burada normal beyin homojenatlanndaki elde edilen iki denatüre PrP substratı tezgah üstü prion dönüştürme reaksiyonlarında kullanıldığı CER tahlili için protokol, (Şekil 1) 13 sunulmaktadır. PH değeri 7.4 &#39;de denatüre alt-tabaka PrP Cı sadece bir tür bariyer 14 yokluğunda reaksiyona içine ekildi PrP TSE PrP res dönüştürülebilir. Bunun aksine, pH 3.5, diğer alt-tabaka PrP C denatürasyonu PrP res aşağıdaki kuluçkalama dönüştürülmesini sağlarve herhangi bir türden elde edilen PrP TSE ile dönüşüm için bir kontrol olarak işlev görür. pH 3.5 substratın pH 7.4 alt-tabaka görece PrP res PrP C dönüşüm oranı tür bariyer bir ölçü sağlar. Bu da, CER deneyi, çeşitli TSElerin laboratuar farelerin türler arası bilinen tahmin eder ve kronik bitkinlik hastalığını (CWD) ve diğer TSEler 14 Hammond koyun dahil olmak üzere birçok memeli türünden, bir tür bariyer tahmin çabalarında deneyi kullandık bulmuşlardır 15. Yararlı Bu metodoloji bulacaksınız TSE türleri engelleri ya da PrP C -to-PRP res dönüşüm değerlendirilmesi hızlı tarama sağlayan bir araç ilgilenen Müfettişler.

<table border="0" cellpadding="0" cellspacing="0" width="944">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:296px;">Name of Material/ Equipment</td>
			<td style="width:205px;">Company</td>
			<td style="width:157px;">Catalog Number</td>
			<td style="width:287px;">Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:296px;">12% Bis-Tris SDS-PAGE gels</td>
			<td style="width:205px;">Life Technologies</td>
			<td style="width:157px;">NP0342</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:296px;">0.5 mm zirconium oxide beads</td>
			<td style="width:205px;">Next Advance</td>
			<td style="width:157px;">ZROB05&#160;</td>
			<td style="width:287px;">Other varieties of beads are also effective</td>
		</tr>
		<tr height="66">
			<td height="66" style="height:66px;width:296px;">Antibodies</td>
			<td style="width:205px;">various suppliers</td>
			<td style="width:157px;"></td>
			<td style="width:287px;">Select appropriate primary and secondary antibodies for immunoblot detection of PrPres from species of interest</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:296px;">Bead homogenizer</td>
			<td style="width:205px;">Next Advance</td>
			<td style="width:157px;">BBY24M</td>
			<td style="width:287px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:296px;">Centrifuge&#160;</td>
			<td style="width:205px;">Beckman Coulter</td>
			<td style="width:157px;">369434</td>
			<td style="width:287px;">High speed with temperature control</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:296px;">Conical tubes</td>
			<td style="width:205px;">any brand</td>
			<td style="width:157px;"></td>
			<td style="width:287px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:296px;">Cotton-tipped applicator</td>
			<td style="width:205px;">Uline</td>
			<td style="width:157px;">S-18991</td>
			<td style="width:287px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:296px;">Cuphorn sonicator</td>
			<td style="width:205px;">Heat Systems-Ultrasonics</td>
			<td style="width:157px;">W-380</td>
			<td style="width:287px;">Heat Systems-Ultrasonics, Inc. is now Qsonica, LLC</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:296px;">Densitometry software program</td>
			<td style="width:205px;">UVP</td>
			<td style="width:157px;">Vision Works LS Image Acquisition and Analysis software</td>
			<td style="width:287px;">Other programs, such as NIH ImageJ, will also work</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:296px;">Dounce homogenizer</td>
			<td style="width:205px;">Kimble Chase</td>
			<td style="width:157px;">885300</td>
			<td style="width:287px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:296px;">End-over-end mixer</td>
			<td style="width:205px;">Labnet International</td>
			<td style="width:157px;">H5600</td>
			<td style="width:287px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Ethylenediaminetetra acetic acid</td>
			<td style="width:205px;">Boston Bioproducts</td>
			<td style="width:157px;">P-770</td>
			<td style="width:287px;">Hazardous chemical: eye irritation</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">Guanidine hydrochloride, 8M</td>
			<td style="width:205px;">Thermo Fisher Scientific</td>
			<td style="width:157px;">24115</td>
			<td style="width:287px;">Hazardous chemical: acute toxicity, skin irritation, eye irritation</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Heating block</td>
			<td style="width:205px;">Fisher Scientific</td>
			<td style="width:157px;">11-718</td>
			<td style="width:287px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Hydrochloric acid</td>
			<td style="width:205px;">Sigma-Aldrich&#160;</td>
			<td style="width:157px;">435570</td>
			<td style="width:287px;">Hazardous chemical: strong acid</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;">Lithium dodecyl sulfate sample buffer, 4X</td>
			<td style="width:205px;">Life Technologies</td>
			<td style="width:157px;">NP0008</td>
			<td style="width:287px;">Hazardous chemical: skin &#38; respiratory irritation, serious eye damage, flammable solid</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">Methanol</td>
			<td style="width:205px;">Fisher Scientific</td>
			<td style="width:157px;">A454-4</td>
			<td style="width:287px;">Hazardous chemical: acute toxicity, flammable liquid</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Microcentrifuge tubes</td>
			<td style="width:205px;">any brand</td>
			<td style="width:157px;"></td>
			<td style="width:287px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Mini-centrifuge</td>
			<td style="width:205px;">Labnet International</td>
			<td style="width:157px;">C1301</td>
			<td style="width:287px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">N-lauroyl-sarcosine (sarkosyl)</td>
			<td style="width:205px;">Sigma-Aldrich&#160;</td>
			<td style="width:157px;">L-5125</td>
			<td style="width:287px;">Hazardous chemical: acute toxicity, skin irritation, eye damage</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:296px;">Nonidet P-40</td>
			<td style="width:205px;">Amresco</td>
			<td style="width:157px;">M158</td>
			<td style="width:287px;">Hazardous chemical: skin irritation, eye damage</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:296px;">SDS-PAGE gel system</td>
			<td style="width:205px;">Life Technologies</td>
			<td style="width:157px;">NuPAGE electrophoresis system</td>
			<td style="width:287px;">Other SDS-PAGE systems will also work</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:296px;">PCR tubes (low-binding)</td>
			<td style="width:205px;">Axygen</td>
			<td style="width:157px;">PCR-02-L-C</td>
			<td style="width:287px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:296px;">Pestle homogenizer</td>
			<td style="width:205px;">Fisher Scientific</td>
			<td style="width:157px;">03-392-106</td>
			<td style="width:287px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:296px;">pH meter</td>
			<td style="width:205px;">Sentron</td>
			<td style="width:157px;">SI600</td>
			<td style="width:287px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:296px;">Polyvinyldifluoride membrane</td>
			<td style="width:205px;">Millipore</td>
			<td style="width:157px;">IPVH00010</td>
			<td style="width:287px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:296px;">Proteinase K</td>
			<td style="width:205px;">Promega</td>
			<td style="width:157px;">V3021</td>
			<td style="width:287px;">Hazardous chemical: skin &#38; eye irritation, respiratory sensitisation, organ toxicity</td>
		</tr>
		<tr height="23">
			<td height="23" style="height:23px;width:296px;">Reducing agent for SDS-PAGE samples, 10X</td>
			<td style="width:205px;">Life Technologies</td>
			<td style="width:157px;">NP0009</td>
			<td style="width:287px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:296px;">Sodium Chloride</td>
			<td style="width:205px;">Fisher Scientific</td>
			<td style="width:157px;">7647-14-5</td>
			<td style="width:287px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:296px;">Sodium deoxycholate</td>
			<td style="width:205px;">Sigma-Aldrich&#160;</td>
			<td style="width:157px;">D6750</td>
			<td style="width:287px;">Hazardous chemical: acute toxicity</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:296px;">Sodium dodecyl sulfate</td>
			<td style="width:205px;">Thermo Fisher Scientific</td>
			<td style="width:157px;">28364</td>
			<td style="width:287px;">Hazardous chemical: acute toxicity, skin irritation, eye damage, flammable solid</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:296px;">Sodium hydroxide</td>
			<td style="width:205px;">Sigma-Aldrich&#160;</td>
			<td style="width:157px;">S5881</td>
			<td style="width:287px;">Hazardous chemica; strong base</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:296px;">Syringe</td>
			<td style="width:205px;">BD Biosciences</td>
			<td style="width:157px;">various</td>
			<td style="width:287px;">Use syringe size appropriate to volumes of substrate to be homogenized</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:296px;">Syringe needles</td>
			<td style="width:205px;">BD Biosciences</td>
			<td style="width:157px;">various</td>
			<td style="width:287px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:296px;">Thermoshaker (PCR tube shaker)</td>
			<td style="width:205px;">Hangzhou All Sheng Instruments</td>
			<td style="width:157px;">MS-100</td>
			<td style="width:287px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:296px;">Tris base</td>
			<td style="width:205px;">Bio Basic&#160;</td>
			<td style="width:157px;">77-86-1</td>
			<td style="width:287px;">Hazardous chemical: skin, eye, respiratory irritation</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:296px;">Triton X-100</td>
			<td style="width:205px;">Integra Chemical Company</td>
			<td style="width:157px;">T756.30.30</td>
			<td style="width:287px;">Hazardous chemical: acute toxicity, eye irritation</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:296px;">Vortexer</td>
			<td style="width:205px;">Fisher Scientific</td>
			<td style="width:157px;">12-812</td>
			<td style="width:287px;"></td>
		</tr>
	</tbody>
</table>

assessing transmissible spongiform encephalopathy species barriers with an in vitro prion protein conversion assay

Studies to understanding interspecies transmission of transmissible spongiform encephalopathies (TSEs, prion diseases) are challenging in that they typically rely upon lengthy and costly in vivo animal challenge studies. A number of in vitro assays have been developed to aid in measuring prion species barriers, thereby reducing animal use and providing quicker results than animal bioassays. Here, we present the protocol for a rapid in vitro prion conversion assay called the conversion efficiency ratio (CER) assay. In this assay cellular prion protein (PrPC) from an uninfected host brain is denatured at both pH 7.4 and 3.5 to produce two substrates. When the pH 7.4 substrate is incubated with TSE agent, the amount of PrPC that converts to a proteinase K (PK)-resistant state is modulated by the original host&#8217;s species barrier to the TSE agent. In contrast, PrPC in the pH 3.5 substrate is misfolded by any TSE agent. By comparing the amount of PK-resistant prion protein in the two substrates, an assessment of the host&#8217;s species barrier can be made. We show that the CER assay correctly predicts known prion species barriers of laboratory mice and, as an example, show some preliminary results suggesting that bobcats (Lynx rufus) may be susceptible to white-tailed deer (Odocoileus virginianus) chronic wasting disease agent.

CER testinin başarılı kullanımı dönüşüm reaksiyonlarında kullanılan substrat çiftlerinin kalitesine büyük ölçüde bağlıdır. Bu nedenle, alt-tabaka çiftini CER hazırlanması için prosedürler takip edilerek, bir kalite kontrol immünoblot (Şekil 2) yapılmalıdır. Her iki yüzeyler için, tahlil imünoblotlama ile 10-25 ul. PrP Cı her alt-tabaka olarak kolaylıkla tespit edilebilir ve PrP C düzeyleri ikisi arasında yaklaşık olarak aynı olmalıdır. Imm?...

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Assessing Transmissible Spongiform Encephalopathy Species Barriers with an In Vitro Prion Protein Conversion Assay

Measuring the barrier to the interspecies transmission of prion diseases is challenging and typically involves animal challenges or biochemical assays. Here, we present an in vitro prion protein conversion assay with the ability to predict species barriers.

Bir ile Bulaşıcı Süngerimsi Ensefalopati Türler Engelleri değerlendirilmesi<em&gt; İn Vitro</em&gt; Prion Proteini Dönüştürme Deneyi

Studies to understanding interspecies transmission of transmissible spongiform encephalopathies (TSEs, prion diseases) are challenging in that they ...

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Assessing Transmissible Spongiform Encephalopathy Species Barriers with an In Vitro Prion Protein Conversion Assay

7.7K Görüntüleme.  USGS National Wildlife Health Center. Measuring the barrier to the interspecies transmission of prion diseases is challenging and typically involves animal challenges or biochemical assays. Here, we present an in vitro prion protein conversion assay with the ability to predict species barriers.

Video: Assessing Transmissible Spongiform Encephalopathy Species Barriers with an In Vitro Prion Protein Conversion Assay

Biomarkers in an Animal Model for Revealing Neural, Hematologic, and Behavioral Correlates of PTSD

Identification of biomarkers representing the evolution of the pathophysiology of Post Traumatic Stress Disorder (PTSD) is vitally important, not only for objective diagnosis but also for the evaluation of therapeutic efficacy and resilience to trauma. Ongoing research is directed at identifying molecular biomarkers for PTSD, including traumatic stress induced proteins, transcriptomes, genomic variances and genetic modulators, using biologic samples from subjects' blood, saliva, urine, and postmortem brain tissues. However, the correlation of these biomarker molecules in peripheral or postmortem samples to altered brain functions associated with psychiatric symptoms in PTSD remains unresolved. Here, we present an animal model of PTSD in which both peripheral blood and central brain biomarkers, as well as behavioral phenotype, can be collected and measured, thus providing the needed correlation of the central biomarkers of PTSD, which are mechanistic and pathognomonic but cannot be collected from people, with the peripheral biomarkers and behavioral phenotypes, which can.
Our animal model of PTSD employs restraint and tail shocks repeated for three continuous days - the inescapable tail-shock model (ITS) in rats. This ITS model mimics the pathophysiology of PTSD 17, 7, 4, 10. We and others have verified that the ITS model induces behavioral and neurobiological alterations similar to those found in PTSD subjects 17, 7, 10, 9. Specifically, these stressed rats exhibit (1) a delayed and exaggerated startle response appearing several days after stressor cessation, which given the compressed time scale of the rat's life compared to a humans, corresponds to the one to three months delay of symptoms in PTSD patients (DSM-IV-TR PTSD Criterian D/E 13), (2) enhanced plasma corticosterone (CORT) for several days, indicating compromise of the hypothalamopituitary axis (HPA), and (3) retarded body weight gain after stressor cessation, indicating dysfunction of metabolic regulation.
The experimental paradigms employed for this model are: (1) a learned helplessness paradigm in the rat assayed by measurement of acoustic startle response (ASR) and a charting of body mass; (2) microdissection of the rat brain into regions and nuclei; (3) enzyme-linked immunosorbent assay (ELISA) for blood levels of CORT; (4) a gene expression microarray plus related bioinformatics tools 18. This microarray, dubbed rMNChip, focuses on mitochondrial and mitochondria-related nuclear genes in the rat so as to specifically address the neuronal bioenergetics hypothesized to be involved in PTSD.

We describe a rat model of post traumatic stress disorder (PTSD) that reveals the persistent alterations in neuroendocrine function and the delayed long-term, exaggerated fear response, characteristic of PTSD patients. The animal model and methods described here are useful for correlating biomarkers in brain nuclei, which are mechanistic but cannot be measured in patients, with biomarkers in peripheral white blood cells, which can.

TSSB, Nöral Hematolojik ve Davranış Bağlantılı Revealing için Hayvan Modelinde Biyobelirteçler

Identification of biomarkers representing the evolution of the pathophysiology of Post Traumatic Stress Disorder (PTSD) is vitally important, not only for ...

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Assessing Teratogenic Changes in a Zebrafish Model of Fetal Alcohol Exposure

Fetal alcohol syndrome (FAS) is a severe manifestation of embryonic exposure to ethanol. It presents with characteristic defects to the face and organs, including mental retardation due to disordered and damaged brain development. Fetal alcohol spectrum disorder (FASD) is a term used to cover a continuum of birth defects that occur due to maternal alcohol consumption, and occurs in approximately 4% of children born in the United States. With 50% of child-bearing age women reporting consumption of alcohol, and half of all pregnancies being unplanned, unintentional exposure is a continuing issue2. In order to best understand the damage produced by ethanol, plus produce a model with which to test potential interventions, we developed a model of developmental ethanol exposure using the zebrafish embryo. Zebrafish are ideal for this kind of teratogen study3-8. Each pair lays hundreds of eggs, which can then be collected without harming the adult fish. The zebrafish embryo is transparent and can be readily imaged with any number of stains. Analysis of these embryos after exposure to ethanol at different doses and times of duration and application shows that the gross developmental defects produced by ethanol are consistent with the human birth defect. Described here are the basic techniques used to study and manipulate the zebrafish FAS model.

In order to understand the molecular mechanisms of the ethanol-induced developmental damage, we have developed a zebrafish model of ethanol exposure and are exploring the physical, cellular, and genetic alterations that occur after ethanol exposure1. We then seek to find potential interventions and rapidly test them in this animal model.

Fetal Alkol Pozlama bir Zebra balığı Modelinde teratojenik değişiklikler değerlendirilmesi

Fetal alcohol syndrome (FAS) is a severe manifestation of embryonic exposure to ethanol. It presents with characteristic defects to the face and organs, ...

Isolation of Soluble and Insoluble PrP Oligomers in the Normal Human Brain

The central event in the pathogenesis of prion diseases involves a conversion of the host-encoded cellular prion protein PrPC into its pathogenic isoform PrPSc 1. PrPC is detergent-soluble and sensitive to proteinase K (PK)-digestion, whereas PrPSc forms detergent-insoluble aggregates and is partially resistant to PK2-6. The conversion of PrPC to PrPSc is known to involve a conformational transition of &alpha;-helical to &beta;-sheet structures of the protein. However, the in vivo pathway is still poorly understood. A tentative endogenous PrPSc, intermediate PrP* or "silent prion", has yet to be identified in the uninfected brain7.
Using a combination of biophysical and biochemical approaches, we identified insoluble PrPC aggregates (designated iPrPC) from uninfected mammalian brains and cultured neuronal cells8, 9. Here, we describe detailed procedures of these methods, including ultracentrifugation in detergent buffer, sucrose step gradient sedimentation, size exclusion chromatography, iPrP enrichment by gene 5 protein (g5p) that specifically bind to structurally altered PrP forms10, and PK-treatment. The combination of these approaches isolates not only insoluble PrPSc and PrPC aggregates but also soluble PrPC oligomers from the normal human brain. Since the protocols described here have been used to isolate both PrPSc from infected brains and iPrPC from uninfected brains, they provide us with an opportunity to compare differences in physicochemical features, neurotoxicity, and infectivity between the two isoforms. Such a study will greatly improve our understanding of the infectious proteinaceous pathogens. The physiology and pathophysiology of iPrPC are unclear at present. Notably, in a newly-identified human prion disease termed variably protease-sensitive prionopathy, we found a new PrPSc that shares the immunoreactive behavior and fragmentation with iPrPC 11, 12. Moreover, we recently demonstrated that iPrPC is the main species that interacts with amyloid-&beta; protein in Alzheimer disease13. In the same study, these methods were used to isolate Abeta aggregates and oligomers in Alzheimer's disease13, suggesting their application to non-prion protein aggregates involved in other neurodegenerative disorders.

A new species of cellular prion protein (PrPC) has recently been identified in uninfected human brains using the methods described here. These methods can be used to isolate various PrP species, while some of them are also useful in isolating other misfolded protein aggregates from human brains.

Normal İnsan Beyin Çözünür ve çözünmez PrP Oligomerleri İzolasyonu

The central event in the pathogenesis of prion diseases involves a conversion of the host-encoded cellular prion protein PrPC into its pathogenic isoform ...

Simulating Pancreatic Neuroplasticity: In Vitro Dual-neuron Plasticity Assay

Neuroplasticity is an inherent feature of the enteric nervous system and gastrointestinal (GI) innervation under pathological conditions. However, the pathophysiological role of neuroplasticity in GI disorders remains unknown. Novel experimental models which allow simulation and modulation of GI neuroplasticity may enable enhanced appreciation of the contribution of neuroplasticity in particular GI diseases such as pancreatic cancer (PCa) and chronic pancreatitis (CP). Here, we present a protocol for simulation of pancreatic neuroplasticity under in vitro conditions using newborn rat dorsal root ganglia (DRG) and myenteric plexus (MP) neurons. This dual-neuron approach not only permits monitoring of both organ-intrinsic and -extrinsic neuroplasticity, but also represents a valuable tool to assess neuronal and glial morphology and electrophysiology. Moreover, it allows functional modulation of supplied microenvironmental contents for studying their impact on neuroplasticity. Once established, the present neuroplasticity assay bears the potential of being applicable to the study of neuroplasticity in any GI organ.

Simulating Pancreatic Neuroplasticity: In Vitro Dual-neuron Plasticity Assay

Neuronal plasticity is an increasingly recognized, but insufficiently understood feature of the gastrointestinal (GI) tract. Here, in the example of human pancreatic disorders, we present an in vitro neuroplasticity assay for the study of neuronal plasticity in the GI tract at both morphological and functional level.

Pankreas Nöroplastisite benzetme:<em&gt; In Vitro</em&gt; Dual-nöron Plastisitesi Deneyi

Neuroplasticity is an inherent feature of the enteric nervous system and gastrointestinal (GI) innervation under pathological conditions. However, the ...

Using Adeno-associated Virus as a Tool to Study Retinal Barriers in Disease

M&#252;ller cells are the principal glial cells of the retina. Their end-feet form the limits of the retina at the outer and inner limiting membranes (ILM), and in conjunction with astrocytes, pericytes and endothelial cells they establish the blood-retinal barrier (BRB). BRB limits material transport between the bloodstream and the retina while the ILM acts as a basement membrane that defines histologically the border between the retina and the vitreous cavity. Labeling M&#252;ller cells is particularly relevant to study the physical state of the retinal barriers, as these cells are an integral part of the BRB and ILM. Both BRB and ILM are frequently altered in retinal disease and are responsible for disease symptoms.
There are several well-established methods to study the integrity of the BRB, such as the Evans blue assay or fluorescein angiography. However these methods do not provide information on the extent of BRB permeability to larger molecules, in nanometer range. Furthermore, they do not provide information on the state of other retinal barriers such as the ILM. To study BRB permeability alongside retinal ILM, we used an AAV based method that provides information on permeability of BRB to larger molecules while indicating the state of the ILM and extracellular matrix proteins in disease states. Two AAV variants are useful for such study: AAV5 and ShH10. AAV5&#160;has a natural tropism for photoreceptors but it cannot get across to the outer retina when administered into the vitreous when the ILM is intact (i.e., in wild-type retinas). ShH10 has a strong tropism towards glial cells and will selectively label M&#252;ller glia in both healthy and diseased retinas. ShH10 provides more efficient gene delivery in retinas where ILM is compromised. These viral tools coupled with immunohistochemistry and blood-DNA analysis shed light onto the state of retinal barriers in disease.

To investigate the blood-retinal barrier permeability and the inner limiting membrane integrity in animal models of retinal disease, we used several adeno-associated virus (AAV) variants as tools to label retinal neurons and glia. Virus mediated reporter gene expression is then used as an indicator of retinal barrier permeability.

Aracı Olarak Adeno-ilişkili virüs kullanarak Hastalığında Retina Engelleri Eğitim için

M&#252;ller cells are the principal glial cells of the retina. Their end-feet form the limits of the retina at the outer and inner limiting membranes ...

A Piglet Model of Neonatal Hypoxic-Ischemic Encephalopathy

Birth asphyxia, which causes hypoxic-ischemic encephalopathy (HIE), accounts for 0.66 million deaths worldwide each year, about a quarter of the world&#8217;s 2.9 million neonatal deaths. Animal models of HIE have contributed to the understanding of the pathophysiology in HIE, and have highlighted the dynamic process that occur in brain injury due to perinatal asphyxia. Thus, animal studies have suggested a time-window for post-insult treatment strategies. Hypothermia has been tested as a treatment for HIE in pdiglet models and subsequently proven effective in clinical trials. Variations of the model have been applied in the study of adjunctive neuroprotective methods and piglet studies of xenon and melatonin have led to clinical phase I and II trials1,2. The piglet HIE model is further used for neonatal resuscitation- and hemodynamic studies as well as in investigations of cerebral hypoxia on a cellular level. However, it is a technically challenging model and variations in the protocol may result in either too mild or too severe brain injury. In this article, we demonstrate the technical procedures necessary for establishing a stable piglet model of neonatal HIE. First, the newborn piglet (&#60; 24 hr old, median weight 1500 g) is anesthetized, intubated, and monitored in a setup comparable to that found in a neonatal intensive care unit. Global hypoxia-ischemia is induced by lowering the inspiratory oxygen fraction to achieve global hypoxia, ischemia through hypotension and a flat trace amplitude integrated EEG (aEEG) indicative of cerebral hypoxia. Survival is promoted by adjusting oxygenation according to the aEEG response and blood pressure. Brain injury is quantified by histopathology and magnetic resonance imaging after 72 hr.

Hypoxic-ischemic encephalopathy following perinatal asphyxia can be studied using animal models. We demonstrate the procedures necessary for establishing a piglet model of neonatal hypoxic-ischemic encephalopathy.

Yenidoğan Hipoksik-İskemik Ensefalopati A Piglet Modeli

Birth asphyxia, which causes hypoxic-ischemic encephalopathy (HIE), accounts for 0.66 million deaths worldwide each year, about a quarter of the ...

Modeling Encephalopathy of Prematurity Using Prenatal Hypoxia-ischemia with Intra-amniotic Lipopolysaccharide in Rats

Encephalopathy of prematurity (EoP) is a term that encompasses the central nervous system (CNS) abnormalities associated with preterm birth. To best advance translational objectives and uncover new therapeutic strategies for brain injury associated with preterm birth, preclinical models of EoP must include similar mechanisms of prenatal global injury observed in humans and involve multiple components of the maternal-placental-fetal system. Ideally, models should produce a similar spectrum of functional deficits in the mature animal and recapitulate multiple aspects of the pathophysiology. To mimic human systemic placental perfusion defects, placental underperfusion and/or chorioamnionitis associated with pathogen-induced inflammation in early preterm birth, we developed a model of prenatal transient systemic hypoxia-ischemia (TSHI) combined with intra-amniotic lipopolysaccharide (LPS). In pregnant Sprague Dawley rats, TSHI via uterine artery occlusion on embryonic day 18 (E18) induces a graded placental underperfusion defect associated with increasing CNS damage in the fetus. When combined with intra-amniotic LPS injections, placental inflammation is increased and CNS damage is compounded with associated white matter, gait and imaging abnormalities. Prenatal TSHI and TSHI+LPS prenatal insults meet several of the criteria of an EoP model including recapitulating the intrauterine insult, causing loss of neurons, oligodendrocytes and axons, loss of subplate, and functional deficits in adult animals that mimic those observed in children born extremely preterm. Moreover, this model allows for the dissection of inflammation induced by divergent injury types.

Encephalopathy of prematurity encompasses the central nervous system abnormalities associated with injury from preterm birth. This report describes a clinically relevant rat model of in utero transient systemic hypoxia-ischemia and intra-amniotic lipopolysaccharide administration (LPS) that mimics chorioamnionitis, and the related impact of infectious stimuli and placental underperfusion on CNS development.

Prematüre Modelleme Ensefalopati Sıçanlarda İçi amniyotik Lipopolisakkarid ile Prenatal Hipoksi-iskemi kullanma

Encephalopathy of prematurity (EoP) is a term that encompasses the central nervous system (CNS) abnormalities associated with preterm birth. To best ...

Assessing Specificity of Anticancer Drugs In Vitro

A procedure for assessing specificity of anticancer drugs in vitro using cultures containing both tumor and non-tumor cells is demonstrated. The key element is the quantitative determination of a tumor-specific genetic alteration in relation to a universal sequence using a dual-probe digital PCR assay and the subsequent calculation of the proportion of tumor cells. The assay is carried out on a culture containing tumor cells of an established line and spiked-in non-tumor cells. The mixed culture is treated with a test drug at various concentrations. After the treatment, DNA is prepared directly from the survived adhesive cells in wells of 96-well plates using a simple and inexpensive method, and subjected to a dual-probe digital PCR assay for measuring a tumor-specific genetic alteration and a reference universal sequence. In the present demonstration, a heterozygous deletion of the NF1 gene is used as the tumor-specific genetic alteration and a RPP30 gene as the reference gene. Using the ratio NF1/RPP30, the proportion of tumor cells was calculated. Since the dose-dependent change of the proportion of tumor cells provides an in vitro indication for specificity of the drug, this genetic and cell-based in vitro assay will likely have application potential in drug discovery. Furthermore, for personalized cancer-care, this genetic- and cell-based tool may contribute to optimizing adjuvant chemotherapy by means of testing efficacy and specificity of candidate drugs using primary cultures of individual tumors.

Assessing Specificity of Anticancer Drugs In Vitro

The goal of this protocol is to assess specificity of anticancer drugs in vitro using mixed cultures containing both tumor and non-tumor cells.

Antikanser İlaçların Özgüllük değerlendirilmesi<em&gt; İn Vitro</em

A procedure for assessing specificity of anticancer drugs in vitro using cultures containing both tumor and non-tumor cells is demonstrated. The key ...

Forskolin-induced Swelling in Intestinal Organoids: An In Vitro Assay for Assessing Drug Response in Cystic Fibrosis Patients

Recently-developed cystic fibrosis transmembrane conductance regulator (CFTR)-modulating drugs correct surface expression and/or function of the mutant CFTR channel in subjects with cystic fibrosis (CF). Identification of subjects that may benefit from these drugs is challenging because of the extensive heterogeneity of CFTR mutations, as well as other unknown factors that contribute to individual drug efficacy. Here, we describe a simple and relatively rapid assay for measuring individual CFTR function and response to CFTR modulators in vitro. Three dimensional (3D) epithelial organoids are grown from rectal biopsies in standard organoid medium. Once established, the organoids can be bio-banked for future analysis. For the assay, 30-80 organoids are seeded in 96-well plates in basement membrane matrix and are then exposed to drugs. One day later, the organoids are stained with calcein green, and forskolin-induced swelling is monitored by confocal live cell microscopy at 37 &#176;C. Forskolin-induced swelling is fully CFTR-dependent and is sufficiently sensitive and precise to allow for discrimination between the drug responses of individuals with different and even identical CFTR mutations. In vitro swell responses correlate with the clinical response to therapy. This assay provides a cost-effective approach for the identification of drug-responsive individuals, independent of their CFTR mutations. It may also be instrumental in the development of future CFTR modulators.

Forskolin-induced Swelling in Intestinal Organoids: An In Vitro Assay for Assessing Drug Response in Cystic Fibrosis Patients

This protocol describes an assay for measuring CFTR function and CFTR modulator responses in cultured tissue from subjects with cystic fibrosis (CF). Biopsy-derived intestinal organoids swell in a cAMP-driven fashion, a response that is defective (or strongly reduced) in CF organoids and can be restored by exposure to CFTR modulators.

Forskolin kaynaklı bağırsak Organoids şişme: Bir<em&gt; İn Vitro</em&gt; Deney Kistik Fibrozis Hastalarında İlaç Tepki değerlendirilmesi için

Recently-developed cystic fibrosis transmembrane conductance regulator (CFTR)-modulating drugs correct surface expression and/or function of the mutant ...

Neonatal Murine Cochlear Explant Technique as an In Vitro Screening Tool in Hearing Research

While there have been remarkable advances in hearing research over the past few decades, there is still no cure for Sensorineural Hearing Loss (SNHL), a condition that typically involves damage to or loss of the delicate mechanosensory structures of the inner ear. Sophisticated in vitro and ex vivo assays have emerged in recent years, enabling the screening of an increasing number of potentially therapeutic compounds while minimizing resources and accelerating efforts to develop cures for SNHL. Though homogenous cultures of certain cell types continue to play an important role in current research, many scientists now rely on more complex organotypic cultures of murine inner ears, also known as cochlear explants. The preservation of organized cellular structures within the inner ear facilitates the in situ evaluation of various components of the cochlear infrastructure, including inner and outer hair cells, spiral ganglion neurons, neurites, and supporting cells. Here we present the preparation, culture, treatment, and immunostaining of neonatal murine cochlear explants. The careful preparation of these explants facilitates the identification of mechanisms that contribute to SNHL and constitutes a valuable tool for the hearing research community.

Neonatal Murine Cochlear Explant Technique as an In Vitro Screening Tool in Hearing Research

The goal of this protocol is to demonstrate the preparation, culture, treatment, and immunostaining of neonatal murine cochlear explants. The technique can be utilized as an in vitro screening tool in hearing research.

Yenidoğan Murin Koklear Explant Tekniği<em&gt; In vitro</em&gt; İşitme Araştırmalarında Tarama Aracı

While there have been remarkable advances in hearing research over the past few decades, there is still no cure for Sensorineural Hearing Loss (SNHL), a ...