Elaine Pranski ve mükemmel teknik yardım için Carolyn Suwyn ve Harry LeVine III, M. Paul Murphy ve Dişli Marla önemli konuşmalar için çok teşekkürler. Finansman RR-00165 PO1AG026423, P50AG025688, AG030539, Woodruff Vakfı ve Emory Üniversitesi Araştırma Komitesi tarafından sağlanmıştır.

Bölüm 1: açıklık doku homojenatlarında Hazırlık <ol><li> Yaklaşık 30 bile havaneli şart vuruş ile (yani ekle 400μl tampon - buz gibi soğuk tampon (artı 2x proteaz inhibitörü kokteyl [Santa Cruz] 0.1M fosfat tamponlu tuzlu [ve Mg + +-serbest Ca + +]) 4 kez hacmi Sabitlenmemiş kortikal doku homojenize Dounce 100 mg doku). </li><li> 3.000 az 5 dakika Spin homojenatlarında g (4 ° C). Dikkatle -80 açıklık süpernatantlar ve bu özler mağaza alikotları kaldırmak ° C kullanana kadar. </li><li> Üreticinin talimatlarına (ThermoFisher) göre, bir bicinchoninic asit (BCA) deneyi ile açıklık homojenatlarında total protein konsantrasyonu (mg / ml) belirleyin. </li></ol> Bölüm 2: SDS-PAGE ile örnek hazırlama <ol><li> Iyi bir 10 ile,% 10-20 Tricine jel (Invitrogen), yanı başına yüklenecek maksimum ses ~ 25μl. Toplam hacmi 2x SDS numune tamponu ve 10x indirgen, yanı başına yüklenecek açıklık Homojenat maksimum ses 10μl. % 20 (w / v) Sade kortikal homojenatlarında 50μg total protein için de izin veren, total protein konsantrasyonu 5 mg / ml &#39;den büyük olması gerekir. Daha az protein 5mg/ml numuneler başına daha az total protein yüklenmesi gerektirecektir. Ancak, yüksek protein düzeyleri monomerik ve toplu Aβ tespiti için en uygun (50 60μg total protein, optimum). Her zaman ortalama toplam protein aynı miktarda yük. </li><li> Her jel için, SeeBlue Plus2 (Invitrogen) gibi bir moleküler ağırlık marker 10μl ile en az bir yük. Pozitif kontrol olarak, sentetik Aβ40 veya başka bir kuyuda Aβ42 peptid (1xPBS içinde seyreltilmiş) 10-100ng çalıştırın. </li><li> Taze çözülmüş, açıklık homojenatlarında kullanarak, buz üzerinde reaksiyon karışımları hazırlayın. Vorteks tüpleri, 5-10 saniye için 100 kuru bir banyo ısı ° C, 5 dakika sonra, hızlı bir şekilde kapağı yoğunlaşma kaldırmak için tüm örnekler dönerler. </li></ol> Bölüm 3: SDS-PAGE Jel elektroforezi <ol><li> Tricine SDS çalışan tampon kullanarak, üreticinin talimatlarına (Invitrogen) göre,% 10-20 Tricine jel üzerine XCell Sure Lock Mini-Cell Gelbox vortekslenmiş numuneleri yükleyin </li><li> Yaklaşık 90 dakika boyunca sabit bir gerilim 125V jel çalıştırın. 4KDa marker bant jel alttan 1 cm kadar numunelerinin çalışılabilmesi edelim. </li></ol> Bölüm 4: Jeller gelen Membranlar aktarma Proteinler <ol><li> Dikkatlice plastik kasa (Invitrogen) üreticinin talimatlarına göre, jeller kaldırmak ve XCell II Blot Modülü içinde transfer sandviç montajı. Pre-Tris-Glycine transfer tampon (% 20 metanol) ile pedleri ve 0.2μm nitroselüloz membranlar ıslak kurutma ve blot pabuçları veya filtre kağıdı / membran sandviç herhangi bir kabarcıkları. </li><li> XCell Gelbox, transfer tamponu ile iç odanın doldurun ve dih 2 O (metanol maruz zamanla plastik gelbox yıpratmak) dış kamara doldurun. </li><li> 2-3 saat boyunca sabit bir 25mA amperajda transfer çalıştırın. </li><li> Transfer tamamlandığında, sandviç yapısızlaştırabileceğimizi ve dih 2 O ve membranlar içine jeller kare plastik petri kaplarına 1xPBS (veya başka uygun bir kap) içine yerleştirin. </li><li> Protein transfer verimliliği görselleştirmek için, jeller Sadece Mavi SafeStain (Invitrogen) ile boyanmış olabilir, Ponceau G Kırmızı leke (Sigma Aldrich) membranlar, hem üreticinin talimatlarına göre. Bu boyama immunoblotting engel olmaz. Boyama yetersiz protein transferi ortaya çıkarsa, Adım 3 transfer süresi değiştirin. </li></ol> Bölüm 5. Antijen-epitop alma ve İmmünoblotting <ol><li> Antijen alma antikor bağlanma membran Aβ epitoplar immunoblotting sırasında ortaya çıkarmada önemli bir adımdır. Herhangi bir vapur, mikrodalga fırın, su banyosu, tutar sabit bir sıcaklık 100 ° C yeterli olacaktır. Bir vapur antijen alımı için, oda sıcaklığında, 1xPBS dolu bir ağır Kapak plastik poşet membran ısı mühür. Sat, önceden ısıtılmış bir vapur düz kese kese genişletmek için ek bir 15 dakika boyunca inkübe başladıktan sonra. Membran aşırı kırışıklıklar önlemek için, poşetten çıkarmadan önce yavaş yavaş soğutmak için izin verin. </li><li> Oda sıcaklığında, membran dikkatle buharda poşetten çıkarın ve 5 dakika 5 dakika (% 0.05 Tween-20 ile Tuzlu, pH 8.0 Tris-Tamponlanmış TBS-T durulama ardından 1xPBS membran, durulama [Sigma] ), yörüngesel bir çalkalayıcı. Titreme, bir saat süreyle bloke çözüm membranı (% 2,5 yağsız süt TBS-T) inkübe edin. Durulama olmadan, (6E10) 1:1,000 [1μg/ml] 1:5,000 [0.2μg/ml] seyreltme Covance, kaçınarak kabarcık engelleme çözümü seyreltilmiş primer antikor içeren bir tabak veya plastik poşet membran transferis Için oda sıcaklığında bir orbital çalkalayıcı 4 sallayarak ° C (uzun inkübasyon daha iyi bir sinyal verebilir) bir saat sonra 24-48 saat inkübe </li><li> TBS-T 30 dakika membran durulayın (tek bir hızlı 3 x 10 dakika çalkalama takip durulama). </li><li> 90 dakika oda sıcaklığında çalkalayıcı engelleme çözümü 1:10,000 seyreltilmiş HRP-konjuge sekonder antikor membran (Amersham ECL koyun anti-fare, GE Healthcare), inkübe edin. </li><li> TBS-T 30 dakika membran durulayın (tek bir hızlı 3 x 10 dakika çalkalama takip durulama). </li><li> Shaker, plastik levha koruyucuları arasındaki, havsız filtre kağıdı üzerinde aşırı reaktif kurulayın ve membran bir film kaset yerleştirmek, 5 dakika boyunca taze SuperSignal West Pico Electrochemiluminescence reaktifi (ThermoFisher) membran kuluçkaya yatmaktadır. Tozsuz Kimwipes gerekirse ek SuperSignal reaktif kurutun. </li><li> 30 dakika 30 saniye aralıklarla Kodak Biomax MR film ortaya çıkarmak ve bir film geliştirici gelişir. 5 dakika sonra, Aβ monomer bantları muhtemelen doymuş olacaktır. </li><li> Membranlar Geri Yükleme sallayarak Plus oda sıcaklığında 30 dakika boyunca tampon sıyırma ve istenirse ek antikorlar ile reprobed (TBS-T durulandıktan sonra) elimden olabilir. </li></ol> Bölüm 6: Temsilcisi immüno: <img src="/files/ftp_upload/1916/1916fig1a.jpg" alt="Şekil 1a" /> <img src="/files/ftp_upload/1916/1916fig1b.jpg" alt="Şekil 1b" /> <img src="/files/ftp_upload/1916/1916fig1c.jpg" alt="Şekil 1c" /> 7 insan denekler 50μg total protein içeren Şekil 1a-c. Aydınlatılmış homojenatlarında multimer Aβ ve APP varlığı için incelenir. Antikor 6E10 İmmünoblotting Aβ monomerlerin, dimerleri, trimerler, tetramers ve tüm Alzheimer durumlarda APP (üst bant) yanı sıra 2 AD durumlarda bol miktarda yüksek molekül ağırlığı Aβ multimerleri ortaya koymaktadır. Sentetik Aβ40 düşük molekül ağırlıklı bantları kimliğini onaylar. AD: Alzheimer hastalığı, LCD&#39;de: demansı olmayan insan (a) 30 dakikalık film pozlama, (b) 5 dakikalık bir film maruz kalma, (c) 30 saniyelik film maruz kalma: Lewy Bodies, ND ile Demans .

<ol>
	<li>Hardy, J., Selkoe, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+amyloid+hypothesis+of+Alzheimer's+disease:+progress+and+problems+on+the+road+to+therapeutics.">The amyloid hypothesis of Alzheimer's disease: progress and problems on the road to therapeutics.</a> Science. 297, 353-356 (2002).</li><li>Haass, C., Selkoe, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Soluble+protein+oligomers+in+neurodegeneration:+lessons+from+the+Alzheimer's+amyloid+beta-peptide.">Soluble protein oligomers in neurodegeneration: lessons from the Alzheimer's amyloid beta-peptide.</a> Nat. Rev. Mol. Cell. Biol. 8, 101-112 (2007).</li><li>Walker, L. C., LeVine, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+cerebral+proteopathies.">The cerebral proteopathies.</a> Neurobiol. Aging. 21, 559-561 (2000).</li><li>Selkoe, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Aging,+amyloid,+and+Alzheimer's+disease:+a+perspective+in+honor.">Aging, amyloid, and Alzheimer's disease: a perspective in honor.</a> of Carl Cotman. Neurochem. Res. 28, 1705-1713 (2003).</li><li>Walsh, D. M., Selkoe, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Abeta+oligomers+-+a+decade+of+discovery.">Abeta oligomers - a decade of discovery.</a> J. Neurochem. 101, 1172-1184 (2007).</li><li>Swerdlow, P. S., Finley, D., Varshavsky, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enhancement+of+immunoblot+sensitivity+by+heating+of+hydrated+filters.">Enhancement of immunoblot sensitivity by heating of hydrated filters.</a> Anal. Biochem. 156, 147-153 (1986).</li><li>Ida, N., Hartmann, T., Pantel, J., Schr&#246;der, J., Zerfass, R., F&#246;rstl, H., Sandbrink, R., Masters, C. L., Beyreuther, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+hetergeneous+A4+peptides+in+human+cerebrospinal+fuid+and+blood+by+a+newly+developed+sensitive+Western+blot+assay.">Analysis of hetergeneous A4 peptides in human cerebrospinal fuid and blood by a newly developed sensitive Western blot assay.</a> J. Biol. Chem. 271, 22908-22914 (1996).</li></ol>

Alzheimer hastalığı 1,4,5 patogenezinde Aβ agregasyonunun önemine rağmen, az sayıda çalışma açıklanan veya insan kortikal doku örnekleri 2 farklı Aβ multimerlerin sayısal dağılımı var. Yaygın olarak kullanılan immünohistokimyasal teknikler sabit kortikal doku, farklı multimer Aβ türlerin ayrımcılığa izin vermez. Sabitlenmemiş kortikal doku homojenatlarında, Aβ multimerleri ayrılmış ve biyokimyasal jel elektroforezi ve antikor tabanlı algılama yöntemleri kullan...

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		<thead>
		<tr>
		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
		</thead>
		<tbody>
		
<tr>
<td>Complete Protease Inhibitor Cocktail Tablets</td>
<td>&nbsp;</td>
<td>Santa Cruz Biotechnology</td>
<td>Sc-29130</td>
<td>1 tablet in 25ml buffer</td>
</tr>
<tr>
<td>BCA Protein Assay kit</td>
<td>&nbsp;</td>
<td>ThermoFisher Scientific</td>
<td>23225</td>
<td>&nbsp;</td>
<tr>
<td>XCell SureLock Mini-Cell and XCell II Blot Module Kit CE Mark</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>EI0002</td>
<td>&nbsp;</td>
<tr>
<td>Novex Tricine SDS Sample Buffer (2X)</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>LC1676</td>
<td>&nbsp;</td>
<tr>
<td>NuPAGE Sample Reducing Agent (10X)</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>NP0004</td>
<td>&nbsp;</td>
<tr>
<td>SeeBlue Plus2 Pre-Stained Standard</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>LC5925</td>
<td>&nbsp;</td>
<tr>
<td>Novex 10-20% Tricine Gel 1.0 mm, 10 well</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>EC6625BOX</td>
<td>&nbsp;</td>
<tr>
<td>Nitrocellulose membranes, 0.2 &mu;m pore size</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>LC2000</td>
<td>&nbsp;</td>
<tr>
<td>Novex Tricine SDS Running Buffer (10X)</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>LC1675</td>
<td>&nbsp;</td>
<tr>
<td>Novex Tris-Glycine Transfer Buffer (25X)</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>LC3675</td>
<td>&nbsp;</td>
<tr>
<td>SimplyBlue SafeStain</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>LC6060</td>
<td>Will not interfere with immunostaining</td>
</tr>
<tr>
<td>ATX Ponceau S Red staining solution</td>
<td>&nbsp;</td>
<td>Sigma Aldrich</td>
<td>09276</td>
<td>Will not interfere with immunostaining</td>
</tr>
<tr>
<td>Kapak heat sealable plastic sample pouches</td>
<td>&nbsp;</td>
<td>Fisher Scientific</td>
<td>0181225AA</td>
<td>&nbsp;</td>
<tr>
<td>6E10 mouse monoclonal antibody to A&beta;(1-16)</td>
<td>&nbsp;</td>
<td>Covance</td>
<td>SIG-39320</td>
<td>Dilute 1:1,000 up to 1:5,000 for WB</td>
</tr>
<tr>
<td>Tween 20</td>
<td>&nbsp;</td>
<td>Sigma Aldrich</td>
<td>P2287</td>
<td>&nbsp;</td>
<tr>
<td>ECL Mouse IgG, HRP-Linked Whole A&beta; (from sheep)</td>
<td>&nbsp;</td>
<td>GE Healthcare Life Sciences</td>
<td>NA931-1ML</td>
<td>Dilute at 1:10,000</td>
</tr>
<tr>
<td>SuperSignal West Pico Chemiluminescent Substrate</td>
<td>&nbsp;</td>
<td>ThermoFisher</td>
<td>34077</td>
<td>&nbsp;</td>
<tr>
<td>Kodak Biomax MR Film</td>
<td>&nbsp;</td>
<td>Carestream Health</td>
<td>870 1302</td>
<td>&nbsp;</td>		</tbody>
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sds-page/immunoblot detection of a&beta; multimers in human cortical tissue homogenates using antigen-epitope retrieval

Β-amiloid anormal katlama ve polimerizasyon (Aβ) peptid Alzheimer hastalığının patogenezinde nörodejeneratif kaskad başlatmak için düşünülüyor<sup&gt; 1</sup&gt;. Alzheimer hastalığında beyin senil plakların çekirdeklerinde bulunan β-sheet-zengin amiloid fibriller içine kendini agregasyonu eğilimli ya da 42 amino asit peptid - Aβ ağırlıklı bir 40. Giderek artan kanıtlar, bu düşük molekül ağırlıklı çözünen Aβ multimerleri fibriler Aβ amiloid daha toksik<sup&gt; 2</sup&gt;. Beyin dokusunda düşük ve yüksek molekül ağırlığı multimer Aβ türlerin tanımlanması ve ölçülmesi, Alzheimer hastalığı araştırmalarında önemli bir hedefi olduğunu ve aynı zamanda istihdam yöntemleri, diğer proteopathies toksik multimerlerin belirlenmesi ve tanımlanması için uygulanabilir<sup&gt; 3</sup&gt;. Doğal olarak ortaya çıkan Aβ multimerleri Aβ-spesifik antikorların immün SDS-poliakrilamid jel elektroforezi ile tespit edilebilir. Ancak, multimer Aβ ayrılması ve algılama, yüksek konsantrasyonlu kortikal homojenatlarında ve küçük gözenek boyutu nitroselüloz membranlar antijen alımı kullanımını gerektirir. Burada bir açıklık insan kortikal homojenatlarında hazırlanması için teknik, SDS-PAGE ile protein ayırma, ve antijen-epitopu alma / Aβ peptidin N-terminal bölgesi için antikor 6E10 Western blotting açıklar. Bu protokolü kullanarak, sürekli olarak insanlarda Alzheimer patolojisi ile Aβ monomerlerin, dimerleri, trimerler, tetramers ve kortikal doku yüksek molekül ağırlığı multimerleri algılayabilir.

Watch this Scientific Journal Video about SDS-PAGE/Immunoblot Detection of AÃŽÂ² Multimers in Human Cortical Tissue Homogenates using Antigen-Epitope Retrieval at JoVE.com

SDS-PAGE/Immunoblot Detection of A&#946; Multimers in Human Cortical Tissue Homogenates using Antigen-Epitope Retrieval

Biz insan kortikal homojenatlarında açıklık, SDS-PAGE ile protein ayırma, antijen alımı ve Aβ peptid antikor immunoblotting hazırlanması için kullanılan bir tekniktir açıklar. Bu protokolü kullanarak, biz sürekli olarak insanlarda Alzheimer patolojisi olan kortikal doku monomerik ve multimer Aβ algılar.

İnsan Kortikal Doku Aβ multimerlerin SDS-PAGE/Immunoblot Algılama Antijen-epitop Alma kullanarak homojenatlarında

The anomalous folding and polymerization of the &beta;-amyloid (A&beta;) peptide is thought to initiate the neurodegenerative cascade in Alzheimer's ...

sds-pageimmunoblot-detection-multimers-human-cortical-tissue

Research

JoVE Journal

Neuroscience

SDS-PAGE/Immunoblot Detection of A&beta; Multimers in Human Cortical Tissue Homogenates using Antigen-Epitope Retrieval

24.0K Görüntüleme.  Emory University. Biz insan kortikal homojenatlarında açıklık, SDS-PAGE ile protein ayırma, antijen alımı ve Aβ peptid antikor immunoblotting hazırlanması için kullanılan bir tekniktir açıklar. Bu protokolü kullanarak, biz sürekli olarak insanlarda Alzheimer patolojisi olan kortikal doku monomerik ve multimer Aβ algılar.

Video: SDS-PAGE/Immunoblot Detection of Aβ Multimers in Human Cortical Tissue Homogenates using Antigen-Epitope Retrieval

Cryopreservation of Cortical Tissue Blocks for the Generation of Highly Enriched Neuronal Cultures

In this study, we outline a standardized protocol for the successful cryopreservation and thawing of cortical brain tissue blocks to generate highly enriched neuronal cultures. For this protocol the freezing medium used is 10% dimethyl sulfoxide (DMSO) diluted in Hank's Buffered Salt Solution (HBSS). Blocks of cortical tissue are transferred to cryovials containing the freezing medium and slowly frozen at -1&deg;C/min in a rate-controlled freezing container. Post-thaw processing and dissociation of frozen tissue blocks consistently produced neuronal-enriched cultures which exhibited rapid neuritic growth during the first 5 days in culture and significant expansion of the neuronal network within 10 days. Immunocytochemical staining with the astrocytic marker glial fibrillary acidic protein (GFAP) and the neuronal marker beta-tubulin class III, revealed high numbers of neurons and astrocytes in the cultures. Generation of neural precursor cell cultures after tissue block dissociation resulted in rapidly expanding neurospheres, which produced large numbers of neurons and astrocytes under differentiating conditions. This simple cryopreservation protocol allows for the rapid, efficient, and inexpensive preservation of cortical brain tissue blocks, which grants increased flexibility for later generation of neuronal, astrocyte, and neuronal precursor cell cultures.

Here, we describe a method for efficient cryopreservation and thawing of cortical brain tissue blocks to generate highly enriched neuronal cultures. This simple protocol provides flexibility for later generation of neuronal, astrocyte, and neuronal precursor cell cultures.

Yüksek zenginleştirilmiş Nöronal Kültürlerin Üretimi için Kortikal Doku Blokları, Kriyoprezervasyon

In this study, we outline a standardized protocol for the successful cryopreservation and thawing of cortical brain tissue blocks to generate highly ...

Nörobilim

Time-lapse Live Imaging of Clonally Related Neural Progenitor Cells in the Developing Zebrafish Forebrain

Precise patterns of division, migration and differentiation of neural progenitor cells are crucial for proper brain development and function1,2. To understand the behavior of neural progenitor cells in the complex in vivo environment, time-lapse live imaging of neural progenitor cells in an intact brain is critically required. In this video, we exploit the unique features of zebrafish embryos to visualize the development of forebrain neural progenitor cells in vivo. We use electroporation to genetically and sparsely label individual neural progenitor cells. Briefly, DNA constructs coding for fluorescent markers were injected into the forebrain ventricle of 22 hours post fertilization (hpf) zebrafish embryos and electric pulses were delivered immediately. Six hours later, the electroporated zebrafish embryos were mounted with low melting point agarose in glass bottom culture dishes. Fluorescently labeled neural progenitor cells were then imaged for 36hours with fixed intervals under a confocal microscope using water dipping objective lens. The present method provides a way to gain insights into the in vivo development of forebrain neural progenitor cells and can be applied to other parts of the central nervous system of the zebrafish embryo.

The present video demonstrates a method which takes advantage of the combination of electroporation and confocal microscopy to perform live imaging on individual neural progenitor cells in the developing zebrafish forebrain. In vivo analysis of the development of forebrain neural progenitor cells at a clonal level can be achieved in this way.

Gelişmekte olan Zebra balığı önbeyin klonal olarak ilişkilidir Sinir Progenitör Hücreler Zaman atlamalı Canlı Görüntüleme

Precise patterns of division, migration and differentiation of neural progenitor cells are crucial for proper brain development and function1,2. To ...

High Sensitivity 5-hydroxymethylcytosine Detection in Balb/C Brain Tissue

DNA hydroxymethylation is a long known modification of DNA, but has recently become a focus in epigenetic research. Mammalian DNA is enzymatically modified at the 5th carbon position of cytosine (C) residues to 5-mC, predominately in the context of CpG dinucleotides. 5-mC is amenable to enzymatic oxidation to 5-hmC by the Tet family of enzymes, which are believed to be involved in development and disease. Currently, the biological role of 5-hmC is not fully understood, but is generating a lot of interest due to its potential as a biomarker. This is due to several groundbreaking studies identifying 5-hydroxymethylcytosine in mouse embryonic stem (ES) and neuronal cells. Research techniques, including bisulfite sequencing methods, are unable to easily distinguish between 5-mC and 5-hmC . A few protocols exist that can measure global amounts of 5-hydroxymethylcytosine in the genome, including liquid chromatography coupled with mass spectrometry analysis or thin layer chromatography of single nucleosides digested from genomic DNA. Antibodies that target 5-hydroxymethylcytosine also exist, which can be used for dot blot analysis, immunofluorescence, or precipitation of hydroxymethylated DNA, but these antibodies do not have single base resolution.In addition, resolution depends on the size of the immunoprecipitated DNA and for microarray experiments, depends on probe design. Since it is unknown exactly where 5-hydroxymethylcytosine exists in the genome or its role in epigenetic regulation, new techniques are required that can identify locus specific hydroxymethylation. The EpiMark 5-hmC and 5-mC Analysis Kit provides a solution for distinguishing between these two modifications at specific loci. The EpiMark 5-hmC and 5-mC Analysis Kit is a simple and robust method for the identification and quantitation of 5-methylcytosine and 5-hydroxymethylcytosine within a specific DNA locus. This enzymatic approach utilizes the differential methylation sensitivity of the isoschizomers MspI and HpaII in a simple 3-step protocol. Genomic DNA of interest is treated with T4-BGT, adding a glucose moeity to 5-hydroxymethylcytosine. This reaction is sequence-independent, therefore all 5-hmC will be glucosylated; unmodified or 5-mC containing DNA will not be affected. This glucosylation is then followed by restriction endonuclease digestion. MspI and HpaII recognize the same sequence (CCGG) but are sensitive to different methylation states. HpaII cleaves only a completely unmodified site: any modification (5-mC, 5-hmC or 5-ghmC) at either cytosine blocks cleavage. MspI recognizes and cleaves 5-mC and 5-hmC, but not 5-ghmC. The third part of the protocol is interrogation of the locus by PCR. As little as 20 ng of input DNA can be used. Amplification of the experimental (glucosylated and digested) and control (mock glucosylated and digested) target DNA with primers flanking a CCGG site of interest (100-200 bp) is performed. If the CpG site contains 5-hydroxymethylcytosine, a band is detected after glucosylation and digestion, but not in the non-glucosylated control reaction. Real time PCR will give an approximation of how much hydroxymethylcytosine is in this particular site. In this experiment, we will analyze the 5-hydroxymethylcytosine amount in a mouse Babl/C brain sample by end point PCR.

The EpiMark 5-hmC and 5-mC Analysis Kit can be used to analyze and quantitate 5-methylcytosine and 5-hydroxymethylcytosine within a spe cific locus. The kit distinguishes 5-mC from 5-hmC by the addition of glucose to the hydroxyl group of 5-hmC via an enzymatic reaction utilizing &beta;-glucosyltransferase (T4-BGT). When 5-hmC occurs In the context of CCGG, this modification converts a cleavable MspI site to a non-cleavable site.

Balb / C Beyin Dokusu Yüksek Hassasiyet 5-hydroxymethylcytosine Algılama

DNA hydroxymethylation is a long known modification of DNA, but has recently become a focus in epigenetic research.   Mammalian DNA is enzymatically ...

Coherence between Brain Cortical Function and Neurocognitive Performance during Changed Gravity Conditions

Previous studies of cognitive, mental and/or motor processes during short-, medium- and long-term weightlessness have only been descriptive in nature, and focused on psychological aspects. Until now, objective observation of neurophysiological parameters has not been carried out - undoubtedly because the technical and methodological means have not been available -, investigations into the neurophysiological effects of weightlessness are in their infancy (Schneider et al. 2008).
While imaging techniques such as positron emission tomography (PET) and magnetic resonance imaging (MRI) would be hardly applicable in space, the non-invasive near-infrared spectroscopy (NIRS) technique represents a method of mapping hemodynamic processes in the brain in real time that is both relatively inexpensive and that can be employed even under extreme conditions. The combination with electroencephalography (EEG) opens up the possibility of following the electrocortical processes under changing gravity conditions with a finer temporal resolution as well as with deeper localization, for instance with electrotomography (LORETA).
Previous studies showed an increase of beta frequency activity under normal gravity conditions and a decrease under weightlessness conditions during a parabolic flight (Schneider et al. 2008a+b). Tilt studies revealed different changes in brain function, which let suggest, that changes in parabolic flight might reflect emotional processes rather than hemodynamic changes. However, it is still unclear whether these are effects of changed gravity or hemodynamic changes within the brain. Combining EEG/LORETA and NIRS should for the first time make it possible to map the effect of weightlessness and reduced gravity on both hemodynamic and electrophysiological processes in the brain. Initially, this is to be done as part of a feasibility study during a parabolic flight. Afterwards, it is also planned to use both techniques during medium- and long-term space flight.
It can be assumed that the long-term redistribution of the blood volume and the associated increase in the supply of oxygen to the brain will lead to changes in the central nervous system that are also responsible for anaemic processes, and which can in turn reduce performance (De Santo et al. 2005), which means that they could be crucial for the success and safety of a mission (Genik et al. 2005, Ellis 2000).
Depending on these results, it will be necessary to develop and employ extensive countermeasures. Initial results for the MARS500 study suggest that, in addition to their significance in the context of the cardiovascular and locomotor systems, sport and physical activity can play a part in improving neurocognitive parameters. Before this can be fully established, however, it seems necessary to learn more about the influence of changing gravity conditions on neurophysiological processes and associated neurocognitive impairment.

The effect of weightlessness and hypergravity on both hemodynamic and electrophysiological processes in the brain is going to be followed during parabolic flight by EEG and NIRS techniques. 
A feasibility study of a more complex experiment, which is planned to carry out during medium- and long-term space flight.

Beyin Kortikal Fonksiyon ve değiştirildi Yerçekimi Koşullar sırasında Nörobilişsel Performansı arasındaki uyum,

Previous studies of cognitive, mental and/or motor processes during short-, medium- and long-term weightlessness have only been descriptive in nature, and ...

Generation of Neural Stem Cells from Discarded Human Fetal Cortical Tissue

Neural stem cells (NSCs) reside along the ventricular zone neuroepithelium during the development of the cortical plate. These early progenitors ultimately give rise to intermediate progenitors and later, the various neuronal and glial cell subtypes that form the cerebral cortex. The capacity to generate and expand human NSCs (so called neurospheres) from discarded normal fetal tissue provides a means with which to directly study the functional aspects of normal human NSC development 1-5. This approach can also be directed toward the generation of NSCs from known neurological disorders, thereby affording the opportunity to identify disease processes that alter progenitor proliferation, migration and differentiation 6-9. We have focused on identifying pathological mechanisms in human Down syndrome NSCs that might contribute to the accelerated Alzheimer's disease phenotype 10,11. Neither in vivo nor in vitro mouse models can replicate the identical repertoire of genes located on human chromosome 21. 
Here we use a simple and reliable method to isolate Down syndrome NSCs from aborted human fetal cortices and grow them in culture. The methodology provides specific aspects of harvesting the tissue, dissection with limited anatomical landmarks, cell sorting, plating and passaging of human NSCs. We also provide some basic protocols for inducing differentiation of human NSCs into more selective cell subtypes.

A simple and reliable method on isolation and culture of neural stem cells from discarded human fetal cortical tissue is described. Cultures derived from known human neurological disorders can be used for characterization of pathological cellular and molecular processes, as well as provide a platform to assess pharmacological efficacy.

Atılan İnsan Fetal Kortikal Doku Sinir Kök Hücre Üretimi

Neural stem cells (NSCs) reside along the ventricular zone neuroepithelium during the development of the cortical plate. These early progenitors ...

Fiber-optic Implantation for Chronic Optogenetic Stimulation of Brain Tissue

Elucidating patterns of neuronal connectivity has been a challenge for both clinical and basic neuroscience. Electrophysiology has been the gold standard for analyzing patterns of synaptic connectivity, but paired electrophysiological recordings can be both cumbersome and experimentally limiting. The development of optogenetics has introduced an elegant method to stimulate neurons and circuits, both in vitro1 and in vivo2,3. By exploiting cell-type specific promoter activity to drive opsin expression in discrete neuronal populations, one can precisely stimulate genetically defined neuronal subtypes in distinct circuits4-6. Well described methods to stimulate neurons, including electrical stimulation and/or pharmacological manipulations, are often cell-type indiscriminate, invasive, and can damage surrounding tissues. These limitations could alter normal synaptic function and/or circuit behavior. In addition, due to the nature of the manipulation, the current methods are often acute and terminal. Optogenetics affords the ability to stimulate neurons in a relatively innocuous manner, and in genetically targeted neurons. The majority of studies involving in vivo optogenetics currently use a optical fiber guided through an implanted cannula6,7; however, limitations of this method include damaged brain tissue with repeated insertion of an optical fiber, and potential breakage of the fiber inside the cannula. Given the burgeoning field of optogenetics, a more reliable method of chronic stimulation is necessary to facilitate long-term studies with minimal collateral tissue damage. Here we provide our modified protocol as a video article to complement the method effectively and elegantly described in Sparta et al.8 for the fabrication of a fiber optic implant and its permanent fixation onto the cranium of anesthetized mice, as well as the assembly of the fiber optic coupler connecting the implant to a light source. The implant, connected with optical fibers to a solid-state laser, allows for an efficient method to chronically photostimulate functional neuronal circuitry with less tissue damage9 using small, detachable, tethers. Permanent fixation of the fiber optic implants provides consistent, long-term in vivo optogenetic studies of neuronal circuits in awake, behaving mice10 with minimal tissue damage.

The development of optogenetics now provides the means to precisely stimulate genetically defined neurons and circuits, both in vitro and in vivo. Here we describe the assembly and implantation of a fiber optic for chronic photostimulation of brain tissue.

Beyin Dokusu Kronik Optogenetic uyarılması için Fiber-optik İmplantasyon

Elucidating patterns of neuronal connectivity has been a challenge for both clinical and basic neuroscience. Electrophysiology has been the gold standard ...

Quantification of Cerebral Vascular Architecture using Two-photon Microscopy in a Mouse Model of HIV-induced Neuroinflammation

Human Immunodeficiency Virus 1 (HIV-1) infection frequently results in HIV-1 Associated Neurocognitive Disorders (HAND), and is characterized by a chronic neuroinflammatory state within the central nervous system (CNS), thought to be driven principally by virally-mediated activation of microglia and brain resident macrophages. HIV-1 infection is also accompanied by changes in cerebrovascular blood flow (CBF), raising the possibility that HIV-associated chronic neuroinflammation may lead to changes in CBF and/or in cerebral vascular architecture. To address this question, we have used a mouse model for HIV-induced neuroinflammation, and we have tested whether long-term exposure to this inflammatory environment may damage brain vasculature and result in rarefaction of capillary networks. In this paper we describe a method to quantify changes in cortical capillary density in a mouse model of neuroinflammatory disease (HIV-1 Tat transgenic mice). This generalizable approach employs in vivo two-photon imaging of cortical capillaries through a thin-skull cortical window, as well as ex vivo two-photon imaging of cortical capillaries in mouse brain sections. These procedures produce images and z-stack files of capillary networks, respectively, which can be then subjected to quantitative analysis in order to assess changes in cerebral vascular architecture.

This paper describes a method by which the vascular architecture in the brain can be quantified using in vivo and ex vivo two-photon microscopy.

HIV kaynaklı Nöroinflamasyondan bir Fare Modeli İki foton Mikroskop kullanarak Serebral Vasküler Mimarlık Niceleme

Human Immunodeficiency Virus 1 (HIV-1) infection frequently results in HIV-1 Associated Neurocognitive Disorders (HAND), and is characterized by a chronic ...

Quantification of Filamentous Actin (F-actin) Puncta in Rat Cortical Neurons

Filamentous actin protein (F-actin) plays a major role in spinogenesis, synaptic plasticity, and synaptic stability. Changes in dendritic F-actin rich structures suggest alterations in synaptic integrity and connectivity. Here we provide a detailed protocol for culturing primary rat cortical neurons, Phalloidin staining for F-actin puncta, and subsequent quantification techniques. First, the frontal cortex of E18 rat embryos are dissociated into low-density cell culture, then the neurons grown in vitro for at least 12-14 days. Following experimental treatment, the cortical neurons are stained with AlexaFluor 488 Phalloidin (to label the dendritic F-actin puncta) and microtubule-associated protein 2 (MAP2; to validate the neuronal cells and dendritic integrity). Finally, specialized software is used to analyze and quantify randomly selected neuronal dendrites. F-actin rich structures are identified on second order dendritic branches (length range 25-75 &#181;m) with continuous MAP2 immunofluorescence. The protocol presented here will be a useful method for investigating changes in dendritic synapse structures subsequent to experimental treatments.

Quantification of Filamentous Actin F-actin Puncta in Rat Cortical Neurons

Filamentous actin (F-actin) plays an important role in spinogenesis, synaptic plasticity, and synaptic stability. Quantification of F-actin puncta is therefore a useful tool to study the integrity of synaptic structures. This protocol describes the procedures of quantifying F-actin puncta labeled with Phalloidin in low-density primary cortical neuronal cultures.

Rat Kortikal Nöronlar Filamentli Aktin (F-aktin) puncta Niceleme

Filamentous actin protein (F-actin) plays a major role in spinogenesis, synaptic plasticity, and synaptic stability. Changes in dendritic F-actin rich ...

Quantification of Endosome and Lysosome Motilities in Cultured Neurons Using Fluorescent Probes

In the brain, membrane trafficking systems play important roles in regulating neuronal functions, such as neuronal morphology, synaptic plasticity, survival, and glial communications. To date, numerous studies have reported that defects in these systems cause various neuronal diseases. Thus, understanding the mechanisms underlying vesicle dynamics may provide influential clues that could aid in the treatment of several neuronal disorders. Here, we describe a method for quantifying vesicle motilities, such as motility distance and rate of movement, using a software plug-in for the ImageJ platform. To obtain images for quantification, we labeled neuronal endosome-lysosome structures with EGFP-tagged vesicle marker proteins and observed the movement of vesicles using a time-lapse microscopy. This method is highly useful and simplify measuring vesicle motility in neurites, such as axons and dendrites, as well as in the soma of both neurons and glial cells. Furthermore, this method can be applied to other cell lines, such as fibroblasts and endothelial cells. This approach could provide a valuable advancement of our understanding of membrane trafficking.

The investigation of membrane trafficking is crucial for understanding neuronal functions. Here, we introduce a method for quantifying vesicle motility in neurons. This is a convenient method that can be adapted to the quantification of membrane trafficking in the nervous system.

Floresan Probları Kullanan Kültürlü Nöronlarda Endozom ve Lizozom Hareketlerinin Nicelendirilmesi

In the brain, membrane trafficking systems play important roles in regulating neuronal functions, such as neuronal morphology, synaptic plasticity, ...

Visualization of Cortical Modules in Flattened Mammalian Cortices

The cortex of mammalian brains is parcellated into distinct substructures or modules. Cortical modules typically lie parallel to the cortical sheet, and can be delineated by certain histochemical and immunohistochemical methods. In this study, we highlight a method to isolate the cortex from mammalian brains and flatten them to obtain sections parallel to the cortical sheet. We further highlight selected histochemical and immunohistochemical methods to process these flattened tangential sections to visualize cortical modules. In the somatosensory cortex of various mammals, we perform cytochrome oxidase histochemistry to reveal body maps or cortical modules representing different parts of the body of the animal. In the medial entorhinal cortex, an area where grid cells are generated, we utilize immunohistochemical methods to highlight modules of genetically determined neurons which are arranged in a grid-pattern in the cortical sheet across several species. Overall, we provide a framework to isolate and prepare layer-wise flattened cortical sections, and visualize cortical modules using histochemical and immunohistochemical methods in a wide variety of mammalian brains.

This article describes a detailed methodology to obtain flattened tangential sections from mammalian cortices and visualize cortical modules using histochemical and immunohistochemical methods.

Görselleştirme düzleştirilmiş memeli Cortices'deki kortikal modülleri

The cortex of mammalian brains is parcellated into distinct substructures or modules. Cortical modules typically lie parallel to the cortical sheet, and ...