Gli autori vorrei ringraziare il Dr. David Rowe per gentilmente fornire i topi transgenici e Li Chen per l'assistenza istologico.
La ricerca riportata in questa pubblicazione è stata sostenuta dal National Institute of Dental & Craniofacial Research del National Institutes of Health, sotto Premio numero K08DE025914 e dalla associazione americana di Fondazione ortodontico per Sumit Yadav.

<ol>
	<li>LeResche, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Epidemiology+of+Temporomandibular+Disorders:+Implications+for+the+Investigation+of+Etiologic+Factors.">Epidemiology of Temporomandibular Disorders: Implications for the Investigation of Etiologic Factors.</a> Crit Rev Oral Biol Med. 8 (3), 291-305 (1997).</li><li>Chen, 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=Altered+functional+loading+causes+differential+effects+in+the+subchondral+bone+and+condylar+cartilage+in+the+temporomandibular+joint+from+young+mice.">Altered functional loading causes differential effects in the subchondral bone and condylar cartilage in the temporomandibular joint from young mice.</a> Osteoarthr Cartil. 17 (3), 354-361 (2009).</li><li>Pirttiniemi, P., Kantomaa, T., Sorsa, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+decreased+loading+on+the+metabolic+activity+of+the+mandibular+condylar+cartilage+in+the+rat.">Effect of decreased loading on the metabolic activity of the mandibular condylar cartilage in the rat.</a> Eur J Orthod. 26 (1), 1-5 (2004).</li><li>Chavan, S. J., Bhad, W. A., Doshi, U. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+temporomandibular+joint+changes+in+Twin+Block+and+Bionator+appliance+therapy:+a+magnetic+resonance+imaging+study.">Comparison of temporomandibular joint changes in Twin Block and Bionator appliance therapy: a magnetic resonance imaging study.</a> Prog Orthod. 15 (57), (2014).</li><li>Dutra, E. 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=Cellular+and+Matrix+Response+of+the+Mandibular+Condylar+Cartilage+to+Botulinum+Toxin.">Cellular and Matrix Response of the Mandibular Condylar Cartilage to Botulinum Toxin.</a> PLoS ONE. 11 (10), 0164599 (2016).</li><li>Benjamin, M., Ralphs, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biology+of+fibrocartilage+cells.">Biology of fibrocartilage cells.</a> Int Rev Cytol. 233, 1-45 (2004).</li><li>Shen, G., Darendeliler, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Adaptive+Remodeling+of+Condylar+Cartilage-+A+Transition+from+Chondrogenesis+to+Osteogenesis.">The Adaptive Remodeling of Condylar Cartilage- A Transition from Chondrogenesis to Osteogenesis.</a> J Dent Res. 84 (8), 691-699 (2005).</li><li>Utreja, 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=Cell+and+matrix+response+of+temporomandibular+cartilage+to+mechanical+loading.">Cell and matrix response of temporomandibular cartilage to mechanical loading.</a> Osteoarthr Cartil. 24 (2), 335-344 (2016).</li><li>Kaul, R., 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+Effect+of+Altered+Loading+on+Mandibular+Condylar+Cartilage.">The Effect of Altered Loading on Mandibular Condylar Cartilage.</a> PLoS ONE. 11 (7), 0160121 (2016).</li><li>Dyment, N. 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=High-Throughput,+Multi-Image+Cryohistology+of+Mineralized+Tissues.">High-Throughput, Multi-Image Cryohistology of Mineralized Tissues.</a> J Vis Exp. , e54468 (2016).</li><li>Kawamoto, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+a+new+adhesive+film+for+the+preparation+of+multi-purpose+fresh-frozen+sections+from+hard+tissues,+whole-animals,+insects+and+plants.">Use of a new adhesive film for the preparation of multi-purpose fresh-frozen sections from hard tissues, whole-animals, insects and plants.</a> Arch Histol Cytol. 66 (2), 123-143 (2003).</li><li>Hayman, A. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tartrate-resistant+acid+phosphatase+(TRAP)+and+the+osteoclast/immune+cell+dichotomy.">Tartrate-resistant acid phosphatase (TRAP) and the osteoclast/immune cell dichotomy.</a> Autoimmunity. 41 (3), 218-223 (2008).</li></ol>

Gli autori non hanno nessun concorrenti interessi finanziari.

Questo manoscritto descritto metodi per la misurazione di morfometrica e analisi cellulare del murini condili mandibolari e mandibole. Le misure morfometriche radiografica è utilizzabile anche per analizzare altre ossa da piccoli animali da esperimento. Inoltre, l'analisi cellulare (cellule quantificazione e mappatura di distanza di cartilagine) non sono limitati al condilo mandibola roditore, ma può essere utilizzato per quantificare le sezioni istologiche di numerosi tessuti.
Modelli di topi transgenici che esprimono reporter fluorescenti sono ottimi strumenti per comprendere visivamente cambiamenti nell'espressione genica. Modello del topo reporter fluorescenti doppio-collagene (Col2a1XCol10a1) utilizzato in questo rapporto era particolarmente adatto per lo studio di MCC, dato che i transgeni sono espressi nella regione prehypertrophic e ipertrofica di MCC così quella distribuzione di collagene potrebbero essere valutati. Se il ricercatore non ha accesso a un modello di topi transgenici che esprimono reporter fluorescenti, altri metodi di analisi di espressione di proteina istologiche, quali l'immunofluorescenza, possono essere utilizzati.
Per le misure morfometriche, il passo fondamentale prima di prendere le immagini di radiografia mobile è quello di rimuovere tutti i tessuti molli della mandibola o delle ossa per essere analizzati. Muscolare eccessivo o molli associata alle ossa potrebbero mascherare le misure reali delle strutture. È importante essere consapevoli dei limiti del sistema di radiografia mobile. Come ogni radiografia, è una rappresentazione 2-dimensionale di una struttura 3-dimensionale, e sovrapposizione di strutture e manufatti deve essere interpretati con cautela. Inoltre, il posizionamento delle ossa nell'armadietto radiografica deve essere coerenza.
La quantificazione cellulare mediante contando il numero di pixel positivo è un metodo efficiente per quantificazione istologica in una regione ricca di cella come MCC, ma la limitazione di questo approccio è che non fornisce il numero preciso delle cellule. Inoltre, dal momento che quantifica solo i pixel selezionati, è consigliabile quantificare tutte le immagini di interesse utilizzando lo stesso pixel "campionamento" per evitare la quantificazione di pixel di diversa intensità quando l'analisi di immagini diverse.
Un Consiglio nel quantificare le sezioni istologiche è generale per analizzare più sezioni seriali di ogni campione (in questo manoscritto, tre sezioni di serie sono state analizzate per ogni condilo), dato che solitamente si osservano variazioni all'interno di ciascun campione.
La metodologia menzionata nei nostri esperimenti è semplice, facile da usare e può essere utilizzata in qualsiasi studio di tessuto mineralizzato che reporter vengono utilizzati topi. Con la metodologia esistente, è possibile visualizzare le celle che sono macchiate per trappola (Col2a1 o Col10a1) o EdU (Col1a1 o Col2a1) prevedendo la co-localizzazione delle cellule.

TMJ è un unico giunto portante che si trova nella regione craniofacial ed è costituito di fibrocartilagine. Il MCC del TMJ è essenziale per la funzione articolare, compreso movimento della mascella senza ostacoli mentre parlando e masticare, ma esso è influenzato dalle malattie degeneranti, compreso l'osteoartrite1. L'ATM ha la capacità di adattarsi a stimoli esterni e le alterazioni di carico, portando a cambiamenti strutturali e cellulari ai componenti del MCC2,3,4,5. Le proprietà portanti di MCC possono essere spiegate dalle interazioni tra i suoi costituenti, compresa l'acqua, la rete di collagene e densamente proteoglicani. Il MCC ha quattro distinte zone cellulari che esprimono diversi tipi di proteine di collagene e non-collagene: 1) l'area superficiale o articolare; 2) la zona proliferativa, composta di cellule mesenchimali indifferenziate e che risponde al carico di richieste; 3) la zona di prehypertrophic, composto da condrociti maturi esprimendo il collagene di tipo 2; e 4) l'ipertrofica di zona, la regione dove i condrociti ipertrofici esprimendo collagene tipo 10 die e sottoposti a calcificazione. La regione non mineralizzato è ricca di proteoglicani che offrono resistenza alle forze di compressione6.
C'è la mineralizzazione continua alla zona ipertrofica del MCC, dove si verifica la transizione da Condrogenesi ad osteogenesi, garantendo la robusta struttura minerale dell'osso subcondrale del condilo mandibolare7. Cambiamenti cellulari nelle regioni unmineralized e mineralizzate in ultima analisi, portano a cambiamenti morfologici e strutturali nel condilo mandibolare e mandibola. Mantenimento dell'omeostasi cellulare tutte le regioni di MCC e la mineralizzazione della porzione subchondral sono essenziali per la salute, capacità di carico e l'integrità dell'ATM.
Il modello di topo transgenico collagene multipli (come descritto da Utreja et al.) 8 è un ottimo strumento da utilizzare per comprendere i cambiamenti nell'espressione di collagene poiché tutti i transgeni sono espressi in MCC. Per un'approfondita valutazione istologica, macchie istologiche sono utilizzate per studiare la deposizione di matrice, mineralizzazione, proliferazione delle cellule e apoptosi, come pure l'espressione della proteina presso gli strati differenti delle cellule del MCC.
In questo manoscritto, istologico e le analisi morfometriche vengono utilizzate per valutare i cambiamenti strutturali e cellulari nell'osso MCC e subcondrale del condilo mandibola di topi. Inoltre, un metodo di quantificazione delle cellule, per analizzare le immagini istologiche fluorescente e per il mapping di vetrini da microscopio chiaro, è descritto. Compressione statica TMJ caricamento metodo che causa cambiamenti cellulari e morfologiche al MCC e subchondral dell'osso9, è illustrata anche per convalidare i nostri metodi.
I metodi descritti qui possono essere utilizzati per determinare morfometriche e cambiamenti istologici nel condilo mandibolare e mandibola di roditori o di analizzare altre regioni di ossificazione endochondral e la morfologia dei tessuti mineralizzati aggiuntive.

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			<td height="21" style="width:392px;height:21px;">MX20 Radiography System</td>
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			<td style="width:119px;"></td>
			<td></td>
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			<td height="21" style="width:392px;height:21px;">Shandon Cryomatrix embedding resin</td>
			<td style="width:219px;">Thermo Scientific</td>
			<td style="width:119px;">6769006</td>
			<td></td>
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			<td height="21" style="width:392px;height:21px;">Manual microscope Axio Imager Z1</td>
			<td style="width:219px;">Carl Zeiss</td>
			<td style="width:119px;">208562</td>
			<td></td>
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			<td height="21" style="width:392px;height:21px;">yellow fluorescent protein filter&#160; - EYFP</td>
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			<td height="21" style="width:392px;height:21px;">cyan fluorescent protein filter - ECFP</td>
			<td style="width:219px;">Chroma Technology Corp</td>
			<td style="width:119px;">49001</td>
			<td></td>
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			<td height="21" style="width:392px;height:21px;">red fluoresecent protein filter - Cy5</td>
			<td style="width:219px;">Chroma Technology Corp</td>
			<td style="width:119px;">49009</td>
			<td></td>
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			<td height="21" style="width:392px;height:21px;">sodium acetate anhydrous</td>
			<td style="width:219px;">Sigma-Aldrich</td>
			<td style="width:119px;">S2889</td>
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			<td height="23" style="width:392px;height:23px;">sodium L-tartrate dibasic dihydrate&#160;</td>
			<td style="width:219px;">Sigma-Aldrich</td>
			<td style="width:119px;">228729</td>
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			<td height="21" style="width:392px;height:21px;">sodium nitrite&#160;</td>
			<td style="width:219px;">Sigma-Aldrich</td>
			<td style="width:119px;">237213</td>
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			<td height="21" style="width:392px;height:21px;">ELF97 substrate</td>
			<td style="width:219px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">E6600</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;">ClickiT EdU Alexa Fluor 594 HCS kit</td>
			<td style="width:219px;">Life Technologies</td>
			<td style="width:119px;">C10339&#160;</td>
			<td>includes EdU (5-ethynyl-2&#39;-deoxyuridine)&#160;</td>
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			<td height="21" style="width:392px;height:21px;">DAPI (4&#39;,6-Diamidino-2-Phenylindole, Dihydrochloride)</td>
			<td style="width:219px;">Thermo Scientific</td>
			<td style="width:119px;">D1306</td>
			<td></td>
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			<td height="21" style="width:392px;height:21px;">Sodium phosphate dibasic&#160;</td>
			<td style="width:219px;">Sigma-Aldrich</td>
			<td>S3264</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="width:392px;height:21px;">Sodium phosphate monobasic&#160;</td>
			<td style="width:219px;">Sigma-Aldrich</td>
			<td style="width:119px;">71505</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="width:392px;height:21px;">Toluidine Blue O&#160;</td>
			<td style="width:219px;">Sigma-Aldrich</td>
			<td style="width:119px;">T3260</td>
			<td></td>
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			<td height="25" style="width:392px;height:25px;">Adobe Photoshop&#160;</td>
			<td style="width:219px;">Adobe Systems Incorporated</td>
			<td style="width:119px;"></td>
			<td></td>
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		<tr height="24">
			<td height="24" style="width:392px;height:24px;">Phosphate buffered saline tablets (PBS)</td>
			<td style="width:219px;">Research Products International</td>
			<td style="width:119px;">P32080-100T</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;">CNA Beta III Nickel-Free Archwire</td>
			<td>Ortho Organizers, Inc.</td>
			<td style="width:119px;"></td>
			<td></td>
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			<td height="21" style="height:21px;">GraphPad Prism&#160;</td>
			<td>GraphPad Software, Inc.</td>
			<td style="width:119px;"></td>
			<td></td>
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a morphometric and cellular analysis method for the murine mandibular condyle

Il giunto temporomandibular (TMJ) ha la capacità di adattarsi agli stimoli esterni, e cambiamenti di carico possa influenzare la posizione dei condili, così come i componenti strutturali e cellulari della cartilagine del condilo mandibola (MCC). Questo manoscritto descrive metodi per l'analisi di questi cambiamenti e un metodo per alterare il caricamento dell'ATM in topi (cioè, alla compressione statica TMJ caricamento). La valutazione strutturale qui illustrata è un approccio semplice morfometriche che utilizza il software Digimizer e viene eseguito nelle radiografie di piccole ossa. Inoltre, l'analisi del cellulare cambia leader alle alterazioni nell'espressione del collagene, rimodellamento osseo, divisione cellulare, e distribuzione di proteoglycan in MCC è descritto. La quantificazione di questi cambiamenti nelle sezioni istologiche - contando i pixel fluorescenti positivi utilizzando software e il mapping di distanza di misurazione di immagine e zona macchiata con Digimizer - è dimostrato anche. I metodi qui illustrati non sono limitati a TMJ murino, ma ha potuto essere usati su altre ossa di piccoli animali da esperimento e in altre regioni di ossificazione endochondral.

Statistiche descrittive sono state effettuate per esaminare la distribuzione delle misure morfometriche (lunghezza mandibular, condylar lunghezza, larghezza condylar) e le analisi istologiche. I risultati sono stati confrontati fra il gruppo caricato (cioè, i topi sottoposti a carico di compressione con la molla in titanio beta) e il gruppo di controllo (cioè, i topi di controllo che non hanno ricevuto alcuna procedura di corrispondenza). Differenze statisticamente significative fra i mezzi sono state determinate mediante test t spaiato e un valore di p < 0,05 è stato ritenuto per essere statisticamente significativa.
Le misure morfometriche, come descritto nel passaggio 4 e nella figura 3, sono state eseguite nelle mandibole di interfaccia caricata e nei gruppi di controllo. Il gruppo caricato ha presentato con lunghezza mandibola significativamente aumentato (caricato: 16.62 ± 0,23 mm contro controllo: 16.21 ± 0,2 mm; p < 0,05) e la lunghezza della testa del condilo (caricato: 4,6 mm, SD 0,08 mm contro controllo: 4,4 mm; SD 0,06; p < 0,05) rispetto al gruppo di controllo. Tuttavia, non c'era differenza significativa nella larghezza del condilo tra gruppi (caricato: 3,06 ± 0,12 mm contro controllo: 2,9 ± 0,11; p = 0,09).
Quantificazione della distribuzione del collagene usando il metodo descritto nel passaggio 8 ha rivelato significativamente ha aumentato l'espressione di Col10a1 in MCC dei condili del gruppo caricato rispetto al controllo (caricato: 4,46 ± 21% contro controllo: 7,50% ± 2.03%; p < 0,005; Figura 8 A e D). D'altra parte, c'era no statisticamente differenza nell'espressione Col2a1 tra il caricato e gruppi di controllo (caricato: 4,85% ± 1.95% contro controllo: 2.92% ± 1,89%; p = 0,13; Figura 8 B ed E). Inoltre, l'analisi dell'attività di trappola ha mostrato le regioni di trappola-positiva aumentate nella regione subcondrale dei condili dei topi caricati (caricato: 5,28% ± 1,45% contro controllo: 2,41% ± 1,39%; p < 0,05; Figura 8 C e F). Allo stesso modo, abbiamo osservato aumento della proliferazione cellulare, come indicato dall'aumentare cellule EdU-positive in MCC del gruppo caricato rispetto ai topi di controllo (caricato: 6,23% ± 1,89% contro controllo: 1,90% ± 1,03%; p < 0,05; Figura 9 A e C).
Distribuzione di proteoglycan in MCC di caricato e topi di controllo è stato quantificato valutando la zona di tinto blu di toluidina e la mappa di distanza, come descritto nel passaggio 9 e Figura 7. Abbiamo trovato mappatura distanza significativamente aumentata in MCC dei condili del gruppo caricato rispetto al controllo (caricato: 210.22 µm ± 4,11 µm contro controllo: 187.36 µm ± 8,64 µm; p < 0,005; Figura 9 B e D). Tuttavia, la zona di proteoglycan-macchiato non era statisticamente differente fra il caricato e gruppi di controllo (caricato: 203,897.93 µm2 ± 10,171.00 µm2 contro controllo: 202,875.09 µm2 ± 33,419.09 µm2; p = 0,94; Figura 9 B ed E)
<img alt="Figure 8" class="xfigimg" src="/files/ftp_upload/55998/55998fig8.jpg"> Figura 8 : Risultati rappresentativi: (A) cellule Col10a1-positive nelle sezioni sagittali del MCC dei condili da controllo e topi caricati. Ci sono numeri aumentati cellule Col10a1-positive nel gruppo caricato (D). (B) cellule Col2a1-positive in controllo e topi caricati. Non c'è alcuna differenza in cellule Col2a1-positive tra gruppi (E). (C) trappola colorazione nei condili di controllo e topi caricati. Attività aumentata di trappola nel gruppo caricato rispetto al controllo (F). Gli istogrammi (D-F) rappresentano i mezzi ± SD per n = 4 per ogni gruppo. * * Significativa differenza tra controllo e caricati nei gruppi (p < 0,005). Barra della scala = 200 µm. <a href="//cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/55998/55998fig8large.jpg" target="_blank">Clicca qui per visualizzare una versione più grande di questa figura.</a>
<img alt="Figure 9" class="xfigimg" src="/files/ftp_upload/55998/55998fig9.jpg"> Figura 9:risultati rappresentativi: (A) EdU colorazione nei condili di controllo e topi caricati. Aumento della proliferazione cellulare nel gruppo caricato, come rappresentato dalla aumentata EdU-positivo cellule (C). (B) toluidina blu colorazione nei condili del controllo e topi caricati. Aumento dello spessore di cartilagine nei topi caricati, come mostrato da mapping di distanza aumentata nel gruppo sperimentale (D). Nessuna differenza nella zona proteoglycan-macchiato tra controllo e nei gruppi caricati ((E)). Istogrammi (C-E) rappresentano i mezzi ± SD per n = 4 per ogni gruppo. * * Significativa differenza tra controllo e caricati nei gruppi (p < 0,005). Barra della scala = 200 µm. <a href="//cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/55998/55998fig9large.jpg" target="_blank">Clicca qui per visualizzare una versione più grande di questa figura.</a>

Watch this Scientific Journal Video about A Morphometric and Cellular Analysis Method for the Murine Mandibular Condyle at JoVE.com

A Morphometric and Cellular Analysis Method for the Murine Mandibular Condyle

Questo manoscritto presenta metodi per l'analisi morfometrica e cambiamenti cellulari all'interno del condilo mandibolare di roditori.

Un metodo di analisi cellulare per condilo mandibolare murino e morfometrica

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8.2K Views.  University of Connecticut Health Center. Questo manoscritto presenta metodi per l'analisi morfometrica e cambiamenti cellulari all'interno del condilo mandibolare di roditori.

Video: A Morphometric and Cellular Analysis Method for the Murine Mandibular Condyle

Use of Rotorod as a Method for the Qualitative Analysis of Walking in Rat

High speed videoanalysis of the details of movement can provide a source of information about qualitative aspects of walking movements. When walking on a rotorod, animals remain in approximately the same place making repetitive movements of stepping. Thus the task provides a rich source of information on the details of foot stepping movements. Subjects were hemi-Parkinson analogue rats, produced by injection of 6-hydroxydopamine (6-OHDA) into the right nigrostriatal bundle to deplete nigrostriatal dopamine (DA). The present report provides a video analysis illustration of animals previously were filmed from frontal, lateral, and posterior views as they walked (15). Rating scales and frame-by-frame replay of the video records of stepping behavior indicated that the hemi-Parkinson rats were chronically impaired in posture and limb use contralateral to the DA-depletion. The contralateral limbs participated less in initiating and sustaining propulsion than the ipsilateral limbs. These deficits secondary to unilateral DA-depletion show that the rotorod provides a use task for the analysis of stepping movements.

The rotorod test is used to assess motor status in the walking movement of hemi-Parkinson analogue rats.

L&#39;uso di Rotorod come un metodo per l&#39;analisi qualitativa del Camminare in Rat

High speed videoanalysis of the details of movement can provide a source of information about qualitative aspects of walking movements. When walking on a ...

Ricerca

Biologia

Murine Renal Transplantation Procedure

Renal orthotopic transplantation in mice is a technically challenging procedure. Although the first kidney transplants in mice were performed by Russell et al over 30 years ago (1) and refined by Zhang et al years later (2), few people in the world have mastered this procedure. In our laboratory we have successfully performed 1200 orthotopic kidney transplantations with &gt; 90% survival rate. The key points for success include stringent control of reperfusion injury, bleeding and thrombosis, both during the procedure and post-transplantation, and use of 10-0 instead of 11-0 suture for anastomoses.
Post-operative care and treatment of the recipient is extremely important to transplant success and evaluation. All renal graft recipients receive antibiotics in the form of an injection of penicillin immediately post-transplant and sulfatrim in the drinking water continually. Overall animal health is evaluated daily and whole blood creatinine analyses are performed routinely with a portable I-STAT machine to assess graft function.

Renal transplantation in mice is a technically challenging procedure that requires careful post-operative care and treatment for success.

Murino procedura trapianto renale

Renal orthotopic transplantation in mice is a technically challenging procedure. Although the first kidney transplants in mice were performed by Russell ...

A Neuronal and Astrocyte Co-Culture Assay for High Content Analysis of Neurotoxicity

High Content Analysis (HCA) assays combine cells and detection reagents with automated imaging and powerful image analysis algorithms, allowing measurement of multiple cellular phenotypes within a single assay. In this study, we utilized HCA to develop a novel assay for neurotoxicity. Neurotoxicity assessment represents an important part of drug safety evaluation, as well as being a significant focus of environmental protection efforts. Additionally, neurotoxicity is also a well-accepted in vitro marker of the development of neurodegenerative diseases such as Alzheimer's and Parkinson's diseases. Recently, the application of HCA to neuronal screening has been reported. By labeling neuronal cells with &beta;III-tubulin, HCA assays can provide high-throughput, non-subjective, quantitative measurements of parameters such as neuronal number, neurite count and neurite length, all of which can indicate neurotoxic effects. However, the role of astrocytes remains unexplored in these models. Astrocytes have an integral role in the maintenance of central nervous system (CNS) homeostasis, and are associated with both neuroprotection and neurodegradation when they are activated in response to toxic substances or disease states. GFAP is an intermediate filament protein expressed predominantly in the astrocytes of the CNS. Astrocytic activation (gliosis) leads to the upregulation of GFAP, commonly accompanied by astrocyte proliferation and hypertrophy. This process of reactive gliosis has been proposed as an early marker of damage to the nervous system. The traditional method for GFAP quantitation is by immunoassay. This approach is limited by an inability to provide information on cellular localization, morphology and cell number. We determined that HCA could be used to overcome these limitations and to simultaneously measure multiple features associated with gliosis - changes in GFAP expression, astrocyte hypertrophy, and astrocyte proliferation - within a single assay. In co-culture studies, astrocytes have been shown to protect neurons against several types of toxic insult and to critically influence neuronal survival. Recent studies have suggested that the use of astrocytes in an in vitro neurotoxicity test system may prove more relevant to human CNS structure and function than neuronal cells alone. Accordingly, we have developed an HCA assay for co-culture of neurons and astrocytes, comprised of protocols and validated, target-specific detection reagents for profiling &beta;III-tubulin and glial fibrillary acidic protein (GFAP). This assay enables simultaneous analysis of neurotoxicity, neurite outgrowth, gliosis, neuronal and astrocytic morphology and neuronal and astrocytic development in a wide variety of cellular models, representing a novel, non-subjective, high-throughput assay for neurotoxicity assessment. The assay holds great potential for enhanced detection of neurotoxicity and improved productivity in neuroscience research and drug discovery.

This article describes a novel protocol and reagent set designed for sensitive measurement of neurotoxic effects of compounds and treatments on co-cultures of neurons and astrocytes using high content analysis. Results demonstrate that high content analysis represents an exciting novel technology for neurotoxicity assessment.

Un neuronale e astrociti Co-Cultura Assay per l&#39;analisi dei contenuti elevati di neurotossicità

High Content Analysis (HCA) assays combine cells and detection reagents with automated imaging and powerful image analysis algorithms, allowing ...

A high-throughput method to globally study the organelle morphology in S. cerevisiae

High-throughput methods to examine protein localization or organelle morphology is an effective tool for studying protein interactions and can help achieve an comprehensive understanding of molecular pathways. In Saccharomyces cerevisiae, with the development of the non-essential gene deletion array, we can globally study the morphology of different organelles like the endoplasmic reticulum (ER) and the mitochondria using GFP (or variant)-markers in different gene backgrounds. However, incorporating GFP markers in each single mutant individually is a labor-intensive process. Here, we describe a procedure that is routinely used in our laboratory. By using a robotic system to handle high-density yeast arrays and drug selection techniques, we can significantly shorten the time required and improve reproducibility. In brief, we cross a GFP-tagged mitochondrial marker (Apc1-GFP) to a high-density array of 4,672 nonessential gene deletion mutants by robotic replica pinning.  Through diploid selection, sporulation, germination and dual marker selection, we recover both alleles. As a result, each haploid single mutant contains Apc1-GFP incorporated at its genomic locus. Now, we can study the morphology of mitochondria in all non-essential mutant background. Using this high-throughput approach, we can conveniently study and delineate the pathways and genes involved in the inheritance and the formation of organelles in a genome-wide setting.

GFP-fusion proteins are widely used to visualize organelles by confocal microscopy. However, screening for mutations that affect the morphology of organelles generally requires individual mutagenesis and is time consuming. Here, we demonstrate a method to simultaneously incorporate organelle-GFP markers in almost 5,000 non-essential genes in yeast.

Un high-throughput metodo per studiare la morfologia globale organello in S. cerevisiae

High-throughput methods to examine protein localization or organelle morphology is an effective tool for studying protein interactions and can help ...

A High-Throughput Method For Zebrafish Sperm Cryopreservation and In Vitro Fertilization

This is a method for zebrafish sperm cryopreservation that is an adaptation of the Harvey method (Harvey et al., 1982).  We have introduced two changes to the original protocol that both streamline the procedure and increase sample uniformity.  First, we normalize all sperm volumes using freezing media that does not contain the cryoprotectant. Second, cryopreserved sperm are stored in cryovials instead of capillary tubes.  The rates of sperm freezing and thawing (&delta;&deg;C/time) are probably the two most critical variables to control in this procedure.  For this reason, do not substitute different tubes for those specified.  Working in teams of 2 it is possible to freeze the sperm of 100 males per team in ~2 hrs.  Sperm cryopreserved using this protocol has an average of 25% fertility (measured as the number of viable embryos generated in an in vitro fertilization divided by the total number of eggs fertilized) and this percent fertility is stable over many years.

A High-Throughput Method For Zebrafish Sperm Cryopreservation and In Vitro Fertilization

This is a high-throughput sperm cryopreservation protocol for zebrafish. Sperm cryopreserved using this protocol has an average of 25% fertility in subsequent vitro fertilization and is stable over many years.

A High-Throughput Metodo per la crioconservazione dello sperma e Zebrafish In Vitro Fecondazione

This is a method for zebrafish sperm cryopreservation that is an adaptation of the Harvey method (Harvey et al., 1982).  We have introduced two changes to ...

A Rapid High-throughput Method for Mapping Ribonucleoproteins (RNPs) on Human pre-mRNA

Sequencing RNAs that co-immunoprecipitate (co-IP) with RNA binding proteins has increased our understanding of splicing by demonstrating that binding location often influences function of a splicing factor.  However, as with any sampling strategy the chance of identifying an RNA bound to a splicing factor is proportional to its cellular abundance.  We have developed a novel in vitro approach for surveying binding specificity on otherwise transient pre-mRNA. This approach utilizes a specifically designed oligonucleotide pool that tiles across introns, exons, splice junctions, or other pre-mRNA.  The pool is subjected to some kind of molecular selection. Here, we demonstrate the method by separating the oligonucleotide into a bound and unbound fraction and utilize a two color array strategy to record the enrichment of each oligonucleotide in the bound fraction. The array data generates high-resolution maps with the ability to identify sequence-specific and structural determinates of ribonucleoprotein (RNP) binding on pre-mRNA.  A unique advantage to this method is its ability to avoid the sampling bias towards mRNA associated with current IP and SELEX techniques, as the pool is specifically designed and synthesized from pre-mRNA sequence. The flexibility of the oligonucleotide pool is another advantage since the experimenter chooses which regions to study and tile across, tailoring the pool to their individual needs.  Using this technique, one can assay the effects of polymorphisms or mutations on binding on a large scale or clone the library into a functional splicing reporter and identify oligonucleotides that are enriched in the included fraction.  This novel in vitro high-resolution mapping scheme provides a unique way to study RNP interactions with transient pre-mRNA species, whose low abundance makes them difficult to study with current in vivo techniques.  



A Rapid High-throughput Method for Mapping Ribonucleoproteins RNPs on Human pre-mRNA

Due to the transient nature of pre-mRNA, it can be difficult to isolate and study in vivo. Here, we present a novel in vitro approach to investigate RNA-protein interactions using a synthetic oligo pool that tiles across selected regions of pre-mRNA.

Un rapido ad alta velocità Metodo per ribonucleoproteine ​​Mapping (RNP) su Human pre-mRNA

Sequencing RNAs that co-immunoprecipitate (co-IP) with RNA binding proteins has increased our understanding of splicing by demonstrating that binding ...

Blue Native Polyacrylamide Gel Electrophoresis (BN-PAGE) for Analysis of Multiprotein Complexes from Cellular Lysates

Multiprotein complexes (MPCs) play a crucial role in cell signalling, since most proteins can be found in functional or regulatory complexes with other proteins (Sali, Glaeser et al. 2003). Thus, the study of protein-protein interaction networks requires the detailed characterization of MPCs to gain an integrative understanding of protein function and regulation. For identification and analysis, MPCs must be separated under native conditions. In this video, we describe the analysis of MPCs by blue native polyacrylamide gel electrophoresis (BN-PAGE). BN-PAGE is a technique that allows separation of MPCs in a native conformation with a higher resolution than offered by gel filtration or sucrose density ultracentrifugation, and is therefore useful to determine MPC size, composition, and relative abundance (Sch&auml;gger and von Jagow 1991); (Sch&auml;gger, Cramer et al. 1994). By this method, proteins are separated according to their hydrodynamic size and shape in a polyacrylamide matrix. Here, we demonstrate the analysis of MPCs of total cellular lysates, pointing out that lysate dialysis is the crucial step to make BN-PAGE applicable to these biological samples. Using a combination of first dimension BN- and second dimension SDS-PAGE, we show that MPCs separated by BN-PAGE can be further subdivided into their individual constituents by SDS-PAGE. Visualization of the MPC components upon gel separation is performed by standard immunoblotting. As an example for MPC analysis by BN-PAGE, we chose the well-characterized eukaryotic 19S, 20S, and 26S proteasomes.

Blue Native Polyacrylamide Gel Electrophoresis BN-PAGE for Analysis of Multiprotein Complexes from Cellular Lysates

In this video, we describe the characterization of multiprotein complexes (MPCs) by blue native polyacrylamide gel electrophoresis (BN-PAGE). In a first dimension, dialyzed cellular lysates are separated by BN-PAGE to identify individual MPCs. In a second dimension SDS-PAGE, MPCs of interest are further subdivided to analyze their constituents by immunoblotting.

Blu nativi poliacrilammide gel elettroforesi (BN-PAGE) per l&#39;analisi di complessi multiproteici da lisati cellulari

Multiprotein complexes (MPCs) play a crucial role in cell signalling, since most proteins can be found in functional or regulatory complexes with other ...

An Explant Assay for Assessing Cellular Behavior of the Cranial Mesenchyme

The central nervous system is derived from the neural plate that undergoes a series of complex morphogenetic movements resulting in formation of the neural tube in a process known as neurulation. During neurulation, morphogenesis of the mesenchyme that underlies the neural plate is believed to drive neural fold elevation. The cranial mesenchyme is comprised of the paraxial mesoderm and neural crest cells. The cells of the cranial mesenchyme form a pourous meshwork composed of stellate shaped cells and intermingling extracellular matrix (ECM) strands that support the neural folds. During neurulation, the cranial mesenchyme undergoes stereotypical rearrangements resulting in its expansion and these movements are believed to provide a driving force for neural fold elevation. However, the pathways and cellular behaviors that drive cranial mesenchyme morphogenesis remain poorly studied. Interactions between the ECM and the cells of the cranial mesenchyme underly these cell behaviors. Here we describe a simple ex vivo explant assay devised to characterize the behaviors of these cells. This assay is amendable to pharmacological manipulations to dissect the signaling pathways involved and live imaging analyses to further characterize the behavior of these cells. We present a representative experiment demonstrating the utility of this assay in characterizing the migratory properties of the cranial mesenchyme on a variety of ECM components.

The cranial mesenchyme undergoes dramatic morphogenic movements that likely provides a driving force for elevation of the neural folds1,2. Here we describe a simple ex vivo explant assay to characterize the cellular behaviors of the cranial mesenchyme during neurulation. This assay has numerous applications including being amenable to pharmacological manipulations and live imaging analyses.

Un test per la valutazione dei comportamenti Espianto cellulare del Mesenchima cranio

The central nervous system is derived from the neural plate that undergoes a series of complex morphogenetic movements resulting in formation of the ...

Single-cell Microinjection for Cell Communication Analysis

Gap junctions are intercellular channels that allow the communication of neighboring cells. This communication depends on the contribution of a hemichannel by each neighboring cell to form the gap junction. In mammalian cells, the hemichannel is formed by six connexins, monomers with four transmembrane domains and a C and N terminal within the cytoplasm. Gap junctions permit the exchange of ions, second messengers, and small metabolites. In addition, they have important roles in many forms of cellular communication within physiological processes such as synaptic transmission, heart contraction, cell growth and differentiation. We detail how to perform a single-cell microinjection of Lucifer Yellow to visualize cellular communication via gap-junctions in living cells. It is expected that in functional gap junctions, the dye will diffuse from the loaded cell to the connected cells. It is a very useful technique to study gap junctions since you can evaluate the diffusion of the fluorescence in real time. We discuss how to prepare the cells and the micropipette, how to use a micromanipulator and inject a low molecular weight fluorescent dye in an epithelial cell line.

We describe here how to perform a single-cell microinjection of Lucifer Yellow to visualize cellular communication via gap-junctions in living cells, and provide some useful tips. We expect that this paper will help everyone to evaluate the degree of cellular coupling due to functional gap junctions. Everything described here could be, in principle, adapted to other fluorescent dyes with molecular weight below 1,000 Daltons.

Microiniezione cella singola per l&#39;analisi cellulare comunicazione

Gap junctions are intercellular channels that allow the communication of neighboring cells. This communication depends on the contribution of a ...

Isolation of Murine Valve Endothelial Cells

Normal valve structures consist of stratified layers of specialized extracellular matrix (ECM) interspersed with valve interstitial cells (VICs) and surrounded by a monolayer of valve endothelial cells (VECs). VECs play essential roles in establishing the valve structures during embryonic development, and are important for maintaining life-long valve integrity and function. In contrast to a continuous endothelium over the surface of healthy valve leaflets, VEC disruption is commonly observed in malfunctioning valves and is associated with pathological processes that promote valve disease and dysfunction. Despite the clinical relevance, focused studies determining the contribution of VECs to development and disease processes are limited. The isolation of VECs from animal models would allow for cell-specific experimentation. VECs have been isolated from large animal adult models but due to their small population size, fragileness, and lack of specific markers, no reports of VEC isolations in embryos or adult small animal models have been reported. Here we describe a novel method that allows for the direct isolation of VECs from mice at embryonic and adult stages. Utilizing the Tie2-GFP reporter model that labels all endothelial cells with Green Fluorescent Protein (GFP), we have been successful in isolating GFP-positive (and negative) cells from the semilunar and atrioventricular valve regions using fluorescence activated cell sorting (FACS). Isolated GFP-positive VECs are enriched for endothelial markers, including CD31 and von Willebrand Factor (vWF), and retain endothelial cell expression when cultured; while, GFP-negative cells exhibit molecular profiles and cell shapes consistent with VIC phenotypes. The ability to isolate embryonic and adult murine VECs allows for previously unattainable molecular and functional studies to be carried out on a specific valve cell population, which will greatly improve our understanding of valve development and disease mechanisms.

The ability to isolate heart valve endothelial cells (VECs) is critical for understanding mechanisms of valve development, maintenance, and disease. Here we describe the isolation of VECs from embryonic and adult Tie2-GFP mice using FACS that will allow for studies determining the contribution of VECs in developmental and disease processes.

Isolamento di cellule murine endoteliali Valve

Normal valve structures consist of stratified layers of specialized extracellular matrix (ECM) interspersed with valve interstitial cells (VICs) and ...