Die Autoren haben nichts zu offenbaren.

1. Montage des Schlaggerätes ( Bild 1 ) <ol><li> Den Kolben aus einer 1 ml Tuberkulinspritze entfernen. Schneiden Sie das Fass auf die 1-ml-Marke. </li><li> Eine Aerosolbarriere (3 mm Höhe x 4 mm Durchmesser) von einer 200 μl Pipettenspitze entfernen und als Impaktor verwenden. Legen Sie den Impaktor in den Spritzenzylinder. Ziehen Sie vorsichtig den Fass, um den Schlagkörper zum Spitzenende zu bewegen, wobei die flache Seite die Düsenöffnung bedeckt. </li><li> Befestigen Sie das Fassspitzenende an Kunststoffschlauch, das mit dem Kohlendioxid (CO 2 ) Durchflussregler einer Drosophila Anästhesiestation verbunden ist. </li><li> Halten Sie den Fass senkrecht und klemmen Sie ihn an einen Standard-Klemmhalterständer, so dass der Impaktor am Boden des Fasses bleibt. </li><li> Ändern Sie eine 200 μl Pipettenspitze, um den Fliegenhalter zu machen. <ol><li> Schneiden Sie 4 mm von der Spitze, um eine Öffnung von 0,8 mm Durchmesser zu machen, so dass nur der Fliegenkopf ausgesetzt werden kann. HINWEIS: Das thoRax und alle anderen Teile des Fliegenkörpers bleiben in der Pipettenspitze. </li></ol></li><li> Ändern Sie eine 1.000 μl Pipettenspitze und eine 1 mL Spritzen-Nadelkappe, um den Stecker herzustellen. <ol><li> 44 mm von der Spitze der Spitze abschneiden. Nehmen Sie eine 6 mm Länge einer 1 mL Spritzen-Nadelkappe und schieben Sie sie fest in das verbleibende Segment der 1.000 μl Pipettenspitze. </li></ol></li></ol> 2. Bedienung des Schlaggerätes <ol><li> Anästhesieren Sie eine einzelne 2-tägige erwachsene weibliche Fliege mit CO 2 auf einem Fliegenkissen. </li><li> Vorsichtig mit einem feinen Pinsel auf den Fliegenhalter übertragen. Tippen Sie sanft auf den Halter, damit der Fliegenkopf außerhalb des Spitzenendes gesehen wird. Wenn der Fliegen-Rüssel außerhalb der Spitze ausgesetzt ist, stecken Sie ihn vorsichtig mit einer abgestumpelten 1-ml-Spritzenadel in die Spitze. HINWEIS: Achten Sie darauf, den Fliegen-Rüssel in der Halterung zu halten. Andernfalls kann die Fliege an einer saugenden Rüsselverletzung sterben. </li><li> Ziehen Sie die Fliege hochMit dem Stecker auf den Spritzenzylinder auftragen, damit der Fliegenkopf nach unten zeigt. </li><li> Den Gasdruck auf 100 kPa einstellen. Stellen Sie den Durchfluss entsprechend dem Experimentdesign ein. </li><li> Schalten Sie den Durchflussregler schnell ein und aus, so dass der Impaktor einmal auf den Fliegenkopf schlägt. </li><li> Heben Sie den Fliegenhalter an und bewegen Sie ihn über ein Fliegenkissen. Den Fliegenhalter umkehren und vorsichtig an die Seite klopfen Lassen Sie die Fliege in einer leeren Ampulle, um sich zu erholen. </li></ol> 3. Video-unterstützte Bewegungsverfolgung <ol><li> Füllen Sie eine Petrischale mit 6 cm Durchmesser mit transparentem Silikon-Elastomer, um die Tracking-Arena zu machen. Lassen Sie einen Abstand von 3 mm zwischen dem Silizium und dem Tellerdeckel, damit die Fliegen frei laufen können, aber nicht fliegen. </li><li> Anästhesieren Sie vier Fliegen aus dem Schein oder der behandelten Gruppe jedes Mal und legen Sie sie in die Arena. Lassen Sie die Fliegen bei 22 ° C für 1 h. </li><li> Positionieren Sie eine Charge-Coupled Device (CCD) Kamera über den Arenen und notieren Sie für 5 min.</li><li> Analysieren Sie die aufgezeichneten Bewegungsbahnen mit Ctrax-Software (frei verfügbar bei Caltech) 16 . Exportieren Sie die verfolgten Daten in einer Programmiersprache (zB Matlab) -kompatibles Format und analysieren Sie die Daten auf der Grundlage der zurückgelegten Strecke pro Rahmen 17 . Berechnen Sie die mittlere Wanderung für jede Fliege und kombinieren Sie sie mit allen anderen aufgezeichneten Fliegen / Gruppe, um eine mittlere kumulative Distanz zu erhalten, die von der Population von Dateien in derselben Gruppe zurückgelegt wird. </li></ol>

<ol>
	<li>McKee, A. C., 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=The+first+NINDS/NIBIB+consensus+meeting+to+define+neuropathological+criteria+for+the+diagnosis+of+chronic+traumatic+encephalopathy.">The first NINDS/NIBIB consensus meeting to define neuropathological criteria for the diagnosis of chronic traumatic encephalopathy.</a> Acta Neuropathol. 131, 75-86 (2016).</li><li>Martland, H. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Punch+drunk.">Punch drunk.</a> JAMA. 91 (15), 1103-1107 (1928).</li><li>Millspaugh, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dementia+pugilistica.">Dementia pugilistica.</a> US Naval Med Bull. 35, 297-303 (1937).</li><li>Omalu, B. I., 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=Chronic+traumatic+encephalopathy+in+a+national+football+league+player:+part+II.">Chronic traumatic encephalopathy in a national football league player: part II.</a> Neurosurgery. 59 (5), 1086-1092 (2006).</li><li>Goldstein, L. E., 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=Chronic+traumatic+encephalopathy+in+blast-exposed+military+veterans+and+a+blast+neurotrauma+mouse+model.">Chronic traumatic encephalopathy in blast-exposed military veterans and a blast neurotrauma mouse model.</a> Sci Transl Med. 4 (134), (2012).</li><li>Mez, J., Stern, R. A., McKee, A. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chronic+traumatic+encephalopathy:+where+are+we+and+where+are+we+going?.">Chronic traumatic encephalopathy: where are we and where are we going?.</a> Curr Neurol Neurosci Rep. 13 (12), 407 (2013).</li><li>McKee, A. C., 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=The+spectrum+of+disease+in+chronic+traumatic+encephalopathy.">The spectrum of disease in chronic traumatic encephalopathy.</a> Brain. 136 (Pt 1), 43-64 (2013).</li><li>Petraglia, A. L., 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=The+spectrum+of+neurobehavioral+sequelae+after+repetitive+mild+traumatic+brain+injury:+a+novel+mouse+model+of+chronic+traumatic+encephalopathy.">The spectrum of neurobehavioral sequelae after repetitive mild traumatic brain injury: a novel mouse model of chronic traumatic encephalopathy.</a> J Neurotrauma. 31 (13), 1211-1224 (2014).</li><li>Hirth, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drosophila+melanogaster+in+the+study+of+human+neurodegeneration.">Drosophila melanogaster in the study of human neurodegeneration.</a> CNS Neurol Disord Drug Targets. 9 (4), 504-523 (2010).</li><li>Littleton, J. T., Ganetzky, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ion+channels+and+synaptic+organization:+analysis+of+the+Drosophila+genome.">Ion channels and synaptic organization: analysis of the Drosophila genome.</a> Neuron. 26 (1), 35-43 (2000).</li><li>Appel, L. F., 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=The+Drosophila+Stubble-stubbloid+gene+encodes+an+apparent+transmembrane+serine+protease+required+for+epithelial+morphogenesis.">The Drosophila Stubble-stubbloid gene encodes an apparent transmembrane serine protease required for epithelial morphogenesis.</a> Proc Natl Acad Sci USA. 90 (11), 4937-4941 (1993).</li><li>Piyankarage, S. C., Featherstone, D. E., Shippy, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanoliter+hemolymph+sampling+and+analysis+of+individual+adult+Drosophila+melanogaster.">Nanoliter hemolymph sampling and analysis of individual adult Drosophila melanogaster.</a> Anal Chem. 84 (10), 4460-4466 (2012).</li><li>Katzenberger, R. J., 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=A+Drosophila+model+of+closed+head+traumatic+brain+injury.">A Drosophila model of closed head traumatic brain injury.</a> Proc Natl Acad Sci USA. 110 (44), E4152-E4159 (2013).</li><li>Barekat, A., 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=Using+Drosophila+as+an+integrated+model+to+study+mild+repetitive+traumatic+brain+injury.">Using Drosophila as an integrated model to study mild repetitive traumatic brain injury.</a> Sci Rep. 6, 25252 (2016).</li><li>Katzenberger, R. J., 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=A+Method+to+Inflict+Closed+Head+Traumatic+Brain+Injury+in+Drosophila.">A Method to Inflict Closed Head Traumatic Brain Injury in Drosophila.</a> J Vis Exp. (e52905), (2015).</li><li>Branson, K., Robie, A. A., Bender, J., Perona, P., Dickinson, M. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-throughput+ethomics+in+large+groups+of+Drosophila.">High-throughput ethomics in large groups of Drosophila.</a> Nat Methods. 6 (6), 451-457 (2009).</li><li>Straw, A. D., Dickinson, M. H., 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=Motmot,+an+open-source+toolkit+for+realtime+video+acquisition+and+analysis.">Motmot, an open-source toolkit for realtime video acquisition and analysis.</a> Source Code Biol Med. 4 (5), 1-10 (2009).</li><li>Talavage, T. 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=Functionally-detected+cognitive+impairment+in+high+school+football+players+without+clinically-diagnosed+concussion.">Functionally-detected cognitive impairment in high school football players without clinically-diagnosed concussion.</a> J Neurotrauma. 31 (4), 327-338 (2014).</li><li>Theadom, A., 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=Frequency+and+impact+of+recurrent+traumatic+brain+injury+in+a+population-based+sample.">Frequency and impact of recurrent traumatic brain injury in a population-based sample.</a> J Neurotrauma. 32 (10), 674-681 (2015).</li><li>Drobysheva, D., 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=An+optimized+method+for+histological+detection+of+dopaminergic+neurons+in+Drosophila+melanogaster.">An optimized method for histological detection of dopaminergic neurons in Drosophila melanogaster.</a> J Histochem Cytochem. 56 (12), 1049-1063 (2008).</li></ol>

Diese Arbeit wurde von der Johns Hopkins University School of Medicine Fakultät Startup Fund an LC unterstützt

Tiermodelle, die CTE-Merkmale, wie neurophysiologische Veränderungen, neuropathologische Kennzeichen und neurobehaviorale Defizite, treu modellieren, sind für die Aufdeckung von Krankheitsmechanismen und für die Entwicklung diagnostischer und therapeutischer Ziele unerlässlich. Es ist verständlich, dass kein Tiermodell einer menschlichen Erkrankung perfekt ist, um alle klinisch relevanten Endpunkte nachzuahmen. Allerdings glauben wir, dass ein robustes CTE-Modell die folgenden drei Anforderungen erfüllen sollte: (...

Chronische Traumatische Enzephalopathie (CTE) wurde vor kurzem als eine deutliche neurodegenerative Erkrankung, getrennt von anderen Tauopathien wie Alzheimer-Krankheit 1 erkannt. Im Gegensatz zu Alzheimer-Krankheit und anderen üblichen Tauopathien, deren wichtigste Risikofaktoren das Alter und eine Familiengeschichte der Demenz vorantreiben, bedeutet CTE, wie durch seinen Namen angedeutet, eine enge Verbindung mit einer Geschichte des Hirntraumas, die höchstwahrscheinlich bei Sportsportlern, Wie Boxer und Fußballspieler, sowie in Militärveteranen 2 , 3 , 4 , 5 . Es wird angenommen, dass sie durch wiederholte, konkurrierende und unerschütterliche Schläge zum Kopf initiiert wird. Patienten können Symptome und Anzeichen wie kognitive Defizite, Stimmungs- und Verhaltensänderungen und Bewegungsdysfunktion darstellen, die sich mit der Alzheimer-Krankheit signifikant überschneiden, frontotemporalDemenz, Lewy-Körper-Demenz und Parkinson-Krankheit 6 . Im Gegensatz dazu zeigen post-mortem-Untersuchungen des Hirngewebes ein deutliches Muster der hyperphosphorylierten Tau-Akkumulation, die kleine Blutgefäße in den Tiefen der kortikalen Sulci umgibt, ein pathognomonisches Merkmal, das bei den anderen degenerativen Zuständen nicht beobachtet wurde 7 . Allerdings ist bislang wenig über die Pathogenese bekannt, die zu einer Manifestation der Krankheit führt. Dies ist zum großen Teil auf das Fehlen eines treuen Tiermodells zurückzuführen - erst vor kurzem wurden Nagetiermodelle erzeugt 5 , 8 . Diese Modellorganismen haben die Nachteile einer kostenintensiven Versorgung und einer relativ langen Lebensdauer, die sich nicht für neurodegenerative Krankheitsstudien eignen. Im Vergleich zu Säugetier-Pendants sind wirbellose Tiere wie Drosophila eine hervorragende Alternative mit ihrer kostengünstigen Instandhaltung,Umfangreiche Werkzeuge zum Sezieren von genetischen Determinanten und relativ kurzer Lebensdauer 9 . Bemerkenswert ist, dass fliege und menschliche Gehirne evolutionär konservierte molekulare und zelluläre Wege sowie anatomische Ähnlichkeiten 10 , 11 , 12 teilen. Zwei geniale Drosophila- Modelle zur Untersuchung traumatischen Hirnverletzungen wurden bisher 13 , 14 gemeldet. Das erste von Katzenberger und Kollegen entworfene &quot;High Impact Trauma&quot; (HIT) -Gerät enthielt frei bewegende Fliegen in einer Plastikfläschchen, die an das freie Ende einer Metallfeder 13 , 15 gebunden war. Als die Plastikfläschchen aufrecht und freigegeben wurde, schlug sie ein Polyurethan-Pad und verlieh den Fliegen ein Trauma, als sie auf die Fläschchenwand prallten und sich erholten. Im Gegensatz dazu haben Barekat und Kollegen eine andere Auslieferungsmethode entworfenDie Omni Perle Ruptor-24 Homogenisatorplattform 14 . Fliegen wurden mit CO 2 unfähig und in ein 2 mL Schraubverschlussrohr gegeben, das an dem Homogenisator befestigt war und vorprogrammierten Schüttelbedingungen unterworfen wurde. Ein Vorteil der Verwendung des Gewebe-Homogenisatorsystems ist, dass der Experimentator die Intensität der Verletzung, die Dauer der Verletzung und die Anzahl der Verletzungskämpfe modulieren könnte. Allerdings leiden beide Regime den gleichen Nachteil: Primäre Verletzungen des Kopfes werden zufällig in Bezug auf die Auswirkungen Lage und Stärke zugefügt. Darüber hinaus führten beide Methoden zu einer beträchtlichen Mortalität, die durch unvermeidliche Kollateralschäden an anderen Körperteilen und inneren Organen verursacht wurde. Hier beschreiben wir eine neuartige Methode, um mTBI in Fruchtfliegen zu induzieren. Unser Gerät besteht aus einem gasbetriebenen ballistischen Impaktor. Im Vergleich zu den bestehenden Drosophila Modellen 14 , 15 hat unsere Methode den einzigartigen Vorteil, Messungen zu liefernDie nur auf den frei beweglichen Fliegenkopf gerichtet ist, so dass die genaue Steuerung verschiedener Faktoren, wie zB Einflussschwere, das Zeitintervall zwischen den Auswirkungen und die Gesamtzahl der anhaltenden Auswirkungen ermöglicht wird.

<table border="0" cellpadding="0" cellspacing="0" width="692">
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">Aerosol Barrier</td>
			<td style="width:151px;">USA Scientific</td>
			<td style="width:119px;">1120-8810</td>
			<td style="width:207px;">Used as an impactor</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">200 ul Pipette Tip</td>
			<td style="width:151px;">USA Scientific</td>
			<td style="width:119px;">1111-0706</td>
			<td>Used as a fly head holder</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">1000 ul Pipette Tip</td>
			<td style="width:151px;">USA Scientific</td>
			<td style="width:119px;">1122-1830</td>
			<td>Used as a connector</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">1 ml Tuberculin Syringe</td>
			<td style="width:151px;">Becton Dickinson</td>
			<td style="width:119px;">309625</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">60 mm Petri Dishes</td>
			<td style="width:151px;">Fisher Scientific</td>
			<td>FB0875713A</td>
			<td>Used as a tracking arenas</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">Flow Regulator</td>
			<td>Genesee Scientific</td>
			<td style="width:119px;">59-122WC</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">Standard Clamp Holder/stand</td>
			<td style="width:151px;">EISCO Scientific</td>
			<td style="width:119px;">CH0688</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">Fine Brush</td>
			<td style="width:151px;">Genesee Scientific</td>
			<td style="width:119px;">59-204</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">Flypad</td>
			<td style="width:151px;">Genesee Scientific</td>
			<td style="width:119px;">59-114</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">Sylgard Silicone Elastomer</td>
			<td style="width:151px;">Dow Corning</td>
			<td>4019862</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">CCD Camera</td>
			<td style="width:151px;">Microsoft&#160;</td>
			<td style="width:119px;">HD-5000</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Ctrax Walking Fly Tracker</td>
			<td style="width:151px;">Caltech</td>
			<td style="width:119px;">Ctrax 0.2.11</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;">MATLAB Image Processing Toolbox</td>
			<td style="width:151px;">MATLAB</td>
			<td style="width:119px;">R2015b</td>
			<td></td>
		</tr>
	</tbody>
</table>

a novel method to model chronic traumatic encephalopathy in drosophila

Chronische traumatische Enzephalopathie (CTE) ist eine etablierte neurodegenerative Erkrankung, die eng mit der Exposition gegenüber repetitiver milder Traumatischer Hirnverletzung (mTBI) assoziiert ist. Die Mechanismen, die für ihre komplexen pathologischen Veränderungen verantwortlich sind, bleiben trotz eines kürzlichen Konsenses, um die neuropathologischen Kriterien zu definieren, weitgehend schwer. Hier beschreiben wir eine neuartige Methode, um ein Modell des CTE in Drosophila melanogaster ( Drosophila ) zu entwickeln, um die Schlüsselgene und Wege zu identifizieren, die zu der charakteristischen hyperphosphorylierten Tauakkumulation und dem neuronalen Tod im Gehirn führen. Einstellbare Festigkeitsstöße, um eine leichte, verletzte Verletzung zuzufügen, werden direkt an den Fliegenkopf abgegeben, wobei der Kopf einer schnellen Beschleunigung und Verzögerung ausgesetzt wird. Unsere Methode eliminiert die potenziellen Probleme, die mit anderen Drosophila- MTBI-Modellen verbunden sind ( zB kann der Todesfall durch Schäden verursacht werdenAndere Körperteile oder innere Organe). Die weniger arbeits- und kostenintensive Tierpflege, die kurze Lebensdauer und umfangreiche genetische Werkzeuge machen die Fruchtfliegen ideal, um die CTE-Pathogenese zu untersuchen und es möglich zu machen, großflächige, genomweit vorwärts genetische und pharmakologische Bildschirme durchzuführen. Wir gehen davon aus, dass die laufende Charakterisierung des Modells wichtige mechanistische Erkenntnisse über Krankheitsverhütung und therapeutische Ansätze generieren wird.

Um ein CTE-Modell mit erwachsenen Drosophila zu etablieren , haben wir die Wirksamkeit unseres Gerätes bei der Vermeidung einer einzigen geschlossenen Verletzung festgestellt. Um die Variationen in Bezug auf Genotyp, Geschlecht oder Alter zu beseitigen, haben wir im Experiment 2-tägige Canton-S WT weibliche Fliegen verwendet. Wir konnten die Festigkeit des Impaktors leicht kontrollieren, indem wir die Strömungsgeschwindigkeit von CO 2 bei einem konstanten Gasdruck ...

Watch this Scientific Journal Video about A Novel Method to Model Chronic Traumatic Encephalopathy in Drosophila at JoVE.com

A Novel Method to Model Chronic Traumatic Encephalopathy in Drosophila

Hier beschreiben wir einen neuen Ansatz, um in Drosophila melanogaster eine geschlossene traumatische Hirnverletzung zuzufügen. Unsere Methode hat den Vorteil, direkt wiederkehrende Stöße mit einstellbarer Kraft auf den Kopf allein zu liefern. Eine weitere Erforschung des wirbellosen Systems wird dazu beitragen, die Pathogenese der chronischen traumatischen Enzephalopathie zu erhellen.

Eine neuartige Methode zur Modellierung chronisch traumatischer Enzephalopathie in<em&gt; Drosophila</em

Chronic Traumatic Encephalopathy (CTE) is an established neurodegenerative disease that is closely associated with exposure to repetitive mild Traumatic ...

a-novel-method-to-model-chronic-traumatic-encephalopathy-in-drosophila

Research

JoVE Journal

Neuroscience

A Novel Method to Model Chronic Traumatic Encephalopathy in Drosophila

8.2K Aufrufe.  Johns Hopkins University School of Medicine.  Hier beschreiben wir einen neuen Ansatz, um in Drosophila melanogaster eine geschlossene traumatische Hirnverletzung zuzufügen. Unsere Methode hat den Vorteil, direkt wiederkehrende Stöße mit einstellbarer Kraft auf den Kopf allein zu liefern. Eine weitere Erforschung des wirbellosen Systems wird dazu beitragen, die Pathogenese der chronischen traumatischen Enzephalopathie zu erhellen. 

Serie: A Novel Method to Model Chronic Traumatic Encephalopathy in Drosophila

Novel Apparatus and Method for Drug Reinforcement

Animal models of reinforcement have proven to be useful for understanding the neurobiological mechanisms underlying drug addiction. Operant drug self-administration and conditioned place preference (CPP) procedures are expansively used in animal research to model various components of drug reinforcement, consumption, and addiction in humans. For this study, we used a novel approach to studying drug reinforcement in rats by combining traditional CPP and self-administration methodologies. We assembled an apparatus using two Med Associate operant chambers, sensory stimuli, and a Plexiglas-constructed neutral zone. These modifications allowed our experiments to encompass motivational aspects of drug intake through self-administration and drug-free assessment of drug/cue conditioning strength with the CPP test. In our experiments, rats self-administered cocaine (0.75 mg/kg/inj, i.v.) during either four (e.g., the "short-term") or eight (e.g., the "long-term") alternating-day sessions in an operant environment containing distinctive sensory cues (e.g., olfactory and visual). On the alternate days, in the other (differently-cued) operant environment, saline was available for self-infusion (0.1 ml, i.v.). Twenty-four hours after the last self-administration/cue-pairing session, a CPP test was conducted. Consistent with typical CPP findings, there was a significant preference for the chamber associated with cocaine self-administration. In addition, in animals undergoing the long-term experiment, a significant positive correlation between CPP magnitude and the number of cocaine-reinforced lever responses. In conclusion, this apparatus and approach is time and cost effective, can be used to examine a wide array of topics pertaining to drug abuse, and provides more flexibility in experimental design than CPP or self-administration methods alone.

Operant drug self-administration and conditioned place preference (CPP) procedures are expansively used in research to model various components of drug reinforcement, consumption, and addiction in humans. In this report, we combined traditional CPP and self-administration methods as a novel approach to studying drug reinforcement and addiction in rats.

Neuartige Geräte und Verfahren zur Drug Reinforcement

Animal models of reinforcement have proven to be useful for understanding the neurobiological mechanisms underlying drug addiction.  Operant drug ...

Forschung

Neurowissenschaften

Lateral Fluid Percussion: Model of Traumatic Brain Injury in Mice

Traumatic brain injury (TBI) research has attained renewed momentum due to the increasing awareness of head injuries, which result in morbidity and mortality. Based on the nature of primary injury following TBI, complex and heterogeneous secondary consequences result, which are followed by regenerative processes 1,2. Primary injury can be induced by a direct contusion to the brain from skull fracture or from shearing and stretching of tissue causing displacement of brain due to movement 3,4. The resulting hematomas and lacerations cause a vascular response 3,5, and the morphological and functional damage of the white matter leads to diffuse axonal injury 6-8. Additional secondary changes commonly seen in the brain are edema and increased intracranial pressure 9. Following TBI there are microscopic alterations in biochemical and physiological pathways involving the release of excitotoxic neurotransmitters, immune mediators and oxygen radicals 10-12, which ultimately result in long-term neurological disabilities 13,14. Thus choosing appropriate animal models of TBI that present similar cellular and molecular events in human and rodent TBI is critical for studying the mechanisms underlying injury and repair.
Various experimental models of TBI have been developed to reproduce aspects of TBI observed in humans, among them three specific models are widely adapted for rodents: fluid percussion, cortical impact and weight drop/impact acceleration 1. The fluid percussion device produces an injury through a craniectomy by applying a brief fluid pressure pulse on to the intact dura. The pulse is created by a pendulum striking the piston of a reservoir of fluid. The percussion produces brief displacement and deformation of neural tissue 1,15. Conversely, cortical impact injury delivers mechanical energy to the intact dura via a rigid impactor under pneumatic pressure 16,17. The weight drop/impact model is characterized by the fall of a rod with a specific mass on the closed skull 18. Among the TBI models, LFP is the most established and commonly used model to evaluate mixed focal and diffuse brain injury 19. It is reproducible and is standardized to allow for the manipulation of injury parameters. LFP recapitulates injuries observed in humans, thus rendering it clinically relevant, and allows for exploration of novel therapeutics for clinical translation 20.
We describe the detailed protocol to perform LFP procedure in mice. The injury inflicted is mild to moderate, with brain regions such as cortex, hippocampus and corpus callosum being most vulnerable. Hippocampal and motor learning tasks are explored following LFP.

Lateral fluid percussion (LFP), an established model of traumatic brain injury in mice, is demonstrated. LFP fulfills three major criteria for animal models: validity, reliability and clinical relevance. The procedure, consisting of surgical craniotomy, fixation of hub followed by induction of injury, resulting in focal and diffuse injuries, is described.

Lateral Fluid-Percussion: Modell Schädel-Hirn-Verletzungen in Mäuse

Traumatic brain injury (TBI) research has attained renewed momentum due to the increasing awareness of head injuries, which result in morbidity and ...

A Low-cost Method for Analyzing Seizure-like Activity and Movement in Drosophila

Video tracking systems have been used widely to analyze Drosophila melanogaster movement and detect various abnormalities in locomotive behavior. While these systems can provide a wealth of behavioral information, the cost and complexity of these systems can be prohibitive for many labs. We have developed a low-cost assay for measuring locomotive behavior and seizure movement in D. melanogaster. The system uses a web-cam to capture images that can be processed using a combination of inexpensive and free software to track the distance moved, the average velocity of movement and the duration of movement during a specified time-span. To demonstrate the utility of this system, we examined a group of D. melanogaster mutants, the Bang-sensitive (BS) paralytics, which are 3-10 times more susceptible to seizure-like activity (SLA) than wild type flies. Using this novel system, we were able to detect that the BS mutant bang senseless (bss) exhibits lower levels of exploratory locomotion in a novel environment than wild type flies. In addition, the system was used to identify that the drug metformin, which is commonly used to treat type II diabetes, reduces the intensity of SLA in the BS mutants.

A Low-cost Method for Analyzing Seizure-like Activity and Movement in Drosophila

Using a webcam and a combination of free and inexpensive software programs, locomotive patterns in Drosophila melanogaster can be analyzed to detect differences in the speed, distance, and time of various motor activities.

Ein Low-Cost-Methode für die Analyse von Beschlagnahme-ähnliche Aktivität und Bewegung in<em&gt; Drosophila</em

Video tracking systems have been used widely to analyze Drosophila melanogaster movement and detect various abnormalities in locomotive behavior. While ...

A Novel Method of Drug Administration to Multiple Zebrafish (Danio rerio) and the Quantification of Withdrawal

Anxiety testing in zebrafish is often studied in combination with the application of pharmacological substances. In these studies, fish are routinely netted and transported between home aquaria and dosing tanks. In order to enhance the ease of compound administration, a novel method for transferring fish between tanks for drug administration was developed. Inserts that are designed for spawning were used to transfer groups of fish into the drug solution, allowing accurate dosing of all fish in the group. This increases the precision and efficiency of dosing, which becomes very important in long schedules of repeated drug administration. We implemented this procedure for use in a study examining the behavior of zebrafish in the light/dark test after administering ethanol with differing 21 day schedules. In fish exposed to daily-moderate amounts of alcohol there was a significant difference in location preference after 2 days of withdrawal when compared to the control group. However, a significant difference in location preference in a group exposed to weekly-binge administration was not observed. 
This protocol can be generalized for use with all types of compounds that are water-soluble and may be used in any situation when the behavior of fish during or after long schedules of drug administration is being examined. The light/dark test is also a valuable method of assessing withdrawal-induced changes in anxiety.

A Novel Method of Drug Administration to Multiple Zebrafish Danio rerio and the Quantification of Withdrawal

A novel method for reducing variability when exposing fish to drugs is explained. Fish exposed to various patterns of ethanol exposure were found to have altered anxiety levels during withdrawal in a light/dark scototaxic assay.

Eine neue Methode der Drug Administration auf mehrere Zebrafisch (<em&gt; Danio rerio</em&gt;) Und die Quantifizierung der Widerrufs

Anxiety testing in zebrafish is often studied in combination with the application of pharmacological substances. In these studies, fish are routinely ...

Quantitative Analysis of Climbing Defects in a Drosophila Model of Neurodegenerative Disorders

Locomotive defects resulting from neurodegenerative disorders can be a late onset symptom of disease, following years of subclinical degeneration, and thus current therapeutic treatment strategies are not curative. Through the use of whole exome sequencing, an increasing number of genes have been identified to play a role in human locomotion. Despite identifying these genes, it is not known how these genes are crucial to normal locomotive functioning. Therefore, a reliable assay, which utilizes model organisms to elucidate the role of these genes in order to identify novel targets of therapeutic interest, is needed more than ever. We have designed a sensitized version of the negative geotaxis assay that allows for the detection of milder defects earlier and has the ability to evaluate these defects over time. The assay is performed in a glass graduated cylinder, which is sealed with a wax barrier film. By increasing the threshold distance to be climbed to 17.5 cm and increasing the experiment duration to 2 min&#160;we have observed a greater sensitivity in detecting mild mobility dysfunctions. The assay is cost effective and does not require extensive training to obtain highly reproducible results. This makes it an excellent technique for screening candidate drugs in Drosophila mutants with locomotion defects.

We present an optimized inexpensive and reliable negative geotaxis assay in Drosophila melanogaster as a model for neurodegenerative disorders. Being more sensitive to mild locomotor defects, this assay will help screen for potential genetic interactions and drug targets.

Quantitative Analyse der Kletter Defekte in einem Drosophila Modell von neurodegenerativen Erkrankungen

Locomotive defects resulting from neurodegenerative disorders can be a late onset symptom of disease, following years of subclinical degeneration, and ...

A Method to Inflict Closed Head Traumatic Brain Injury in Drosophila

Traumatic brain injury (TBI) affects millions of people each year, causing impairment of physical, cognitive, and behavioral functions and death. Studies using Drosophila have contributed important breakthroughs in understanding neurological processes. Thus, with the goal of understanding the cellular and molecular basis of TBI pathologies in humans, we developed the High Impact Trauma (HIT) device to inflict closed head TBI in flies. Flies subjected to the HIT device display phenotypes consistent with human TBI such as temporary incapacitation and progressive neurodegeneration. The HIT device uses a spring-based mechanism to propel flies against the wall of a vial, causing mechanical damage to the fly brain. The device is inexpensive and easy to construct, its operation is simple and rapid, and it produces reproducible results. Consequently, the HIT device can be combined with existing experimental tools and techniques for flies to address fundamental questions about TBI that can lead to the development of diagnostics and treatments for TBI. In particular, the HIT device can be used to perform large-scale genetic screens to understand the genetic basis of TBI pathologies.

A Method to Inflict Closed Head Traumatic Brain Injury in Drosophila

Here we describe a method to inflict closed head traumatic brain injury (TBI) in Drosophila. This method provides a gateway to investigate the cellular and molecular mechanisms that underlie TBI pathologies using the vast array of experimental tools and techniques available for flies.

Eine Methode, um geschlossene Kopftraumatische Hirnverletzung in Verursacht<em&gt; Drosophila</em

Traumatic brain injury (TBI) affects millions of people each year, causing impairment of physical, cognitive, and behavioral functions and death. Studies ...

Recording EEG in Freely Moving Neonatal Rats Using a Novel Method

EEG is a useful method to detect electrical activity in the brain. Moreover, it is a widely used diagnostic tool for various neurological conditions, such as epilepsy and neurodegenerative disorders. However, it is technically difficult to obtain EEG recordings in neonates as it requires specialized handling and great care. Here, we present a novel method to record EEG in neonatal rat pups (P8-P15). We designed a simple and reliable electrode using computer pin loci; it can be easily implanted into the skull of a rat pup to record high-quality EEG signals in the normal and epileptic brain. Pups were given an intraperitoneal (i.p.) injection of the neurotoxin kainic acid (KA) to induce epileptic seizures. The surgical implantation performed in this procedure is less expensive than other EEG procedures for neonates. This method allows one to record high-quality and stable EEG signals for more than 1 week. Furthermore, this procedure can also be applied to adult rats and mice to study epilepsy or other neurological disorders.

Here, we introduce a novel technique designed to record electroencephalography (EEG) in freely moving neonatal epileptic pups and describe its procedures, features, and applications. This method allows one to record EEG for more than 1 week.

Aufzeichnung von EEG in frei bewegten neonatalen Ratten mit einer neuartigen Methode

EEG is a useful method to detect electrical activity in the brain. Moreover, it is a widely used diagnostic tool for various neurological conditions, such ...

Novel Assay for Cold Nociception in Drosophila Larvae

How organisms sense and respond to noxious temperatures is still poorly understood. Further, the mechanisms underlying sensitization of the sensory machinery, such as in patients experiencing peripheral neuropathy or injury-induced sensitization, are not well characterized. The genetically tractable Drosophila model has been used to study the cells and genes required for noxious heat detection, which has yielded multiple conserved genes of interest. Little is known however about the cells and receptors important for noxious cold sensing. Although, Drosophila does not survive prolonged exposure to cold temperatures (&#8804;10 &#186;C), and will avoid cool, preferring warmer temperatures in behavioral preference assays, how they sense and possibly avoid noxious cold stimuli has only recently been investigated.
Here we describe and characterize the first noxious cold (&#8804;10 &#186;C) behavioral assay in Drosophila. Using this tool and assay, we show an investigator how to qualitatively and quantitatively assess cold nociceptive behaviors. This can be done under normal/healthy culture conditions, or presumably in the context of disease, injury or sensitization. Further, this assay can be applied to larvae selected for desired genotypes, which might impact thermosensation, pain, or nociceptive sensitization. Given that pain is a highly conserved process, using this assay to further study&#160;thermal nociception will likely glean important understanding of pain processes in other species, including vertebrates.

Novel Assay for Cold Nociception in Drosophila Larvae

Here we demonstrate a novel assay to study cold nociception in Drosophila larvae. This assay utilizes a custom-built Peltier probe capable of applying a focal noxious cold stimulus and results in quantifiable cold-specific behaviors. This technique will allow further cellular and molecular dissection of cold nociception.

Neuartige Assay für kalte Nozizeption in<em&gt; Drosophila</em&gt; Larvae

How organisms sense and respond to noxious temperatures is still poorly understood. Further, the mechanisms underlying sensitization of the sensory ...

CMAP Scan MUNE (MScan) - A Novel Motor Unit Number Estimation (MUNE) Method

Like other methods for motor unit number estimation (MUNE), compound muscle action potential (CMAP) scan MUNE (MScan) is a non-invasive electrophysiologic method to estimate the number of functioning motor units in a muscle. MUNE is an important tool for the assessment of neuropathies and neuronopathies. Unlike most MUNE methods in use, MScan assesses all the motor units in a muscle, by fitting a model to a detailed stimulus-response curve, or CMAP scan. It thereby avoids the bias inherent in all MUNE methods based on extrapolating from a small sample of units. Like &#39;Bayesian MUNE,&#39;&#160;MScan analysis works by fitting a model, made up of motor units with different amplitudes, thresholds, and threshold variabilities, but the fitting method is quite different, and completed within five minutes, rather than several hours. The MScan off-line analysis works in two stages: first, a preliminary model is generated based on the slope and variance of the points in the scan, and second, this model is then refined by adjusting all the parameters to improve the fit between the original scan and scans generated by the model.
This new method has been tested for reproducibility and recording time on 22 amyotrophic lateral sclerosis (ALS) patients and 20 healthy controls, with each test repeated twice by two blinded physicians. MScan showed excellent intra- and inter-rater reproducibility with ICC values of &#62;0.98 and a coefficient of variation averaging 12.3 &#177; 1.6%. There was no difference in the intra-rater reproducibility between the two observers. Average recording time was 6.27 &#177; 0.27 min.
This protocol describes how to record a CMAP scan and how to use the MScan software to derive an estimate of the number and sizes of the functioning motor units. MScan is a fast, convenient, and reproducible method, which may be helpful in diagnoses and monitoring disease progression in neuromuscular disorders.

CMAP Scan MUNE MScan - A Novel Motor Unit Number Estimation MUNE Method

This protocol describes a new method to estimate the number of functioning motor units in a muscle, by fitting a model to a detailed stimulus-response curve of the compound muscle action potential. It is quick and easy to perform and analyze and has excellent reproducibility.

CMAP Scannen MUNE (MScan) - eine neuartige Motoreinheit Nummer (MUNE) Schätzmethode

Like other methods for motor unit number estimation (MUNE), compound muscle action potential (CMAP) scan MUNE (MScan) is a non-invasive electrophysiologic ...

A Novel In Vitro Model of Blast Traumatic Brain Injury

Traumatic brain injury is a leading cause of death and disability in military and civilian populations. Blast traumatic brain injury results from the detonation of explosive devices, however, the mechanisms that underlie the brain damage resulting from blast overpressure exposure are not entirely understood and are believed to be unique to this type of brain injury. Preclinical models are crucial tools that contribute to better understand blast-induced brain injury. A novel in vitro blast TBI model was developed using an open-ended shock tube to simulate real-life open-field blast waves modelled by the Friedlander waveform. C57BL/6N mouse organotypic hippocampal slice cultures were exposed to single shock waves and the development of injury was characterized up to 72 h using propidium iodide, a well-established fluorescent marker of cell damage that only penetrates cells with compromised cellular membranes. Propidium iodide fluorescence was significantly higher in the slices exposed to a blast wave when compared with sham slices throughout the duration of the protocol. The brain tissue injury is very reproducible and proportional to the peak overpressure of the shock wave applied.

A Novel In Vitro Model of Blast Traumatic Brain Injury

This paper describes a novel model of primary blast traumatic brain injury. A compressed-air driven shock tube is used to expose in vitro mouse hippocampal slice cultures to a single shock wave. This is a simple and rapid protocol generating a reproducible brain tissue injury with a high throughput.

Eine neuartige In-vitro- Modell von traumatischen Hirnverletzungen Blast

Traumatic brain injury is a leading cause of death and disability in military and civilian populations. Blast traumatic brain injury results from the ...