Ringraziamo il Dr. Jeffrey Caplan per la sua formazione e consulenza su confocale. Ringraziamo anche il Keck Electron Microscopy Lab e il Dr. Chaoying Ni per l&#39;assistenza SEM. Questo lavoro è finanziato dal National Institutes of Health (NIDCD, R01DC008965 e R01DC011377). ABZ riconosce NSF Integrativa Graduate Education &amp; Research tirocinio programma (IGERT) per il finanziamento.

Bioreattore Assembly 1. (Video 1) <ol><li> Effettuare uno stampo di alluminio (pressofusione circolare + perno distanziale) con pre-determinati dimensioni interne ed esterne (Figura 1). </li><li> Utilizzando lo stampo dal punto 1.1, fabbricare una membrana di silicone (diametro: 42 mm, spessore: 1,5 mm Figura 1) con un manicotto radicata (diametro: 12 mm, spessore ~ 0,25 millimetri, forma dal perno distanziale in figura 1) mezzo utilizzando un kit disponibile in commercio elastomero siliconico. </li><li> Effettuare una coppia di blocchi acrilici (Figura 2 (4, 5)) con un foro circolare (diametro: 24 mm) al centro, incidere la parte superiore (spessore 1,8 centimetri) e inferiore (spessore 0,9 centimetri) blocchi con nervature ei solchi corrispondenti . 10 </li><li> Panino la membrana di silicone tra i blocchi acrilici associati. Fissare il gruppo con quattro viti d&#39;angolo con un cacciavite coppia di micro impostato su una forza costante (35 cN · m). Come risultato, una tenuta d&#39;acqua, 24 mm di larghezza e 18 mm camera di vibrazione profonda viene creato (Figura 2C). </li><li> Montare un &quot;extended range mini-woofer 3 (Figura 2D, 8 Ω/20 W) sotto la camera di vibrazione attraverso un altro set di viti d&#39;angolo sul blocco acrilico fondo. A questo punto, un singolo modulo vibrazione viene assemblato. </li><li> Replicare sette moduli aggiuntivi vibrazioni. Applicare quattro di loro in uno dei due bar in alluminio fissi (40 cm x 10 cm x 2,5 cm), ponendo le basi degli altoparlanti a fori circolari equidistanti (diametro: 7 cm, spessore: 2 cm) tagliate a barre. Stabilizzare ciascun diffusore inserendo una vite attraverso il lato della barra di alluminio in ogni foro circolare. </li><li> Controllare singolarmente i diffusori da un selettore speaker. Collegare i singoli diffusori al selettore collegando fili agli ingressi positivo e negativo sul corpo diffusore poi alle uscite corrispondenti sul selettore. Il selettore altoparlante consente al segnale da tegli generatore di funzioni, dopo il passaggio attraverso un amplificatore di potenza, di raggiungere tutti otto altoparlanti contemporaneamente (Figura 2E). </li><li> Posizionare i due array da camera, il selettore speaker ed elettronica associati in un recinto anti-umidità. Casa l&#39;intero gruppo in uno spot coltura cellulare incubatore. </li><li> Far passare i cavi principali (attraverso un tubo in PVC di grado medicale) che collega l&#39;amplificatore di potenza e selettore diffusore attraverso il gruppo filtro posteriore del termostato. </li></ol> 2. Fabrication Scaffold e Caratterizzazione <ol><li> Sciogliere pellet PCL in cloroformio ad una concentrazione del 15% in peso. Caricare la soluzione in una siringa da 10 ml con tappo con un ago smussato-ended 21 G. </li><li> Bloccare la siringa su una pompa a siringa programmabile e impostare la portata a 1 ml / hr. </li><li> Posizionare il collettore foglio di alluminio coperto di fronte l&#39;ago in senso orizzontale, con un ago punta a collettore distanza di ~ 18 cm. </li><li> Bloccare il alli positivogator clip per mezzo dell&#39;ago, e il coccodrillo terra al collettore di alluminio, quindi impostare la tensione dell&#39;alimentatore ad alta tensione a 15 kV. ATTENZIONE: alta tensione, mantenere la distanza dal ago. </li><li> Sequenzialmente accendere la pompa a siringa e alimentazione; rapidamente pulito / rimuovere la soluzione di polimero residuo circonda la punta dell&#39;ago con un tovagliolo di carta asciutto prima getti fibre stabile e Taylor cono 19 sono formate. </li><li> Lasciare le fibre di accumulare sul collettore Al ad uno spessore di 250-300 micron ~ (~ 7 ore sotto le condizioni di filatura correnti). Conservare i ponteggi risultanti in un essiccatore a vuoto per 1-2 giorni per rimuovere qualsiasi solvente residuo. </li><li> Immagine i ponteggi, farfugliare ricoperti di oro, utilizzando un microscopio elettronico a scansione per mostrare fibra morfologia coerente. 10 </li></ol> 3. Assemblea bioreattore e Caratterizzazione <ol><li> Punch un disco cilindrica (diametro 8 mm), con quattro braccia (lunghezza: 2mm) dal tappeto come filato PCL (Figura 2A), utilizzando dapprima a 12 mm di diametro biopsia per tagliare il diametro esterno del disco. Quindi utilizzare un secondo, 8 millimetri biopsia per fare quattro due millimetri lunghi tacche equidistanti attorno alla lama circolare per segnare dove le braccia sono da tagliare. Dopo aver eseguito con il punzone 8 mm utilizzare una lama di bisturi per tagliare i bordi delle braccia verso l&#39;esterno. Inserire il scaffold nella scanalatura della membrana di silicone con le braccia tese (Video 1). Appiattire l&#39;impalcatura inserita premendo delicatamente la superficie con una pinzetta piatta. </li><li> Collegare un piccolo pezzo di sottile foglio di alluminio (8 mm x 2 mm forma ortogonale, Figura 2B) al patibolo PCL per aiutare la riflessione laser. </li><li> Fissare il silicone membrana / scaffold PCL assemblato (come specificato nel punto 1.4), nella camera di vibrazione. Aggiungere 1,5 ml di acqua nella camera per idratare il scaffold PCL prima vibrazione. </li><li> Utilizzando il generatore di funzioni, introdurre segno vibrazioniALS (ad esempio, 200 Hz onde sinusoidali con una tensione picco-picco, Vpp, di 0,1 V) alla camera acrilico sandwich. Utilizzare un voltmetro per misurare con precisione la tensione in ogni ingresso diffusore. Nota: la lettura Vpp dal generatore di funzione diverso dal l&#39;eventuale tensione erogata all&#39;altoparlante. </li><li> Montare l&#39;unico punto LDV e fissare il sensore laser testa in fibra ottica a un treppiede testa pan-tilt. Angle la testa del sensore in modo che sia rivolta perpendicolare al tavolo. Collegare la testa del sensore LDV al modulo di acquisizione dati via cavo coassiale quindi il modulo al portatile tramite USB. </li><li> Focalizzare il fascio laser perpendicolarmente in vari punti predeterminati sulla membrana di silicone (Figura 2B e Figura 3). </li><li> Utilizzando il software di acquisizione dati, registrare lo spostamento intermedio membrana. Fare clic su &quot;Impostazioni di acquisizione&quot; dal menu &quot;Opzioni&quot;; quindi cambiare la modalità di misura a &quot;FFT221;. Quindi, fare clic su &quot;Misura continua&quot; nella barra degli strumenti principale quindi il picco che si forma alla frequenza prescelta (Figura 6D) per registrare lo spostamento. </li><li> Graficamente lo spostamento intermedio membrana normale (w 0) in funzione della posizione relativa sul substrato. Costruire una mappa di colori 3D del profilo di vibratorio superficie con Origin software di analisi dei dati 8.5. </li></ol> 4. Cell Culture vibrante <ol><li> MSC derivate dal midollo osseo sub-cultura umana nei T150 fiasche di coltura tissutale ad una densità di semina iniziale di 4000-5000 cellule / cm 2 in MSC manutenzione media. </li><li> Dopo 7-8 giorni di coltura cellulare (a ~ 85% di confluenza), trypsinize le cellule con un reagente di dissociazione cellulare come accutase, contare con un emocitometro, centrifuga (440 xg per 5 min), e risospendere il pellet cellulare in mezzi freschi manutenzione MSC ad una concentrazione di 4,5 x 10 6 cellule / ml. </li><li> Immergere la scaffo PCLld in etanolo al 70% O / N. Dopo che il solvente viene evaporato, esporre entrambi i lati del ponteggio per germicida luce UV (254 nm) per 5-8 min. </li><li> Bagnare il scaffold PCL in una soluzione fibronectina 20 ug / ml a 37 ° C per 1 ora. Inserire il scaffold fibronectina rivestite nella membrana di silicone. Montare il bioreattore come descritto al punto 1. </li><li> Distribuire 40 ml di sospensione cellulare uniformemente sulla forca PCL protetto. Permettono alle cellule di attaccarsi per 1-1,5 ore prima di aggiungere un ulteriore 1,5 ml di mezzi freschi alla camera vibrazioni. </li><li> Cultura patibolo PCL MSC-carico statico per 3 giorni e aggiornare il supporto dopo il completamento della cultura statica. </li><li> Imporre regimi di vibrazione selezionati i costrutti cellulari. Nota: Per esempio, le cellule vengono sottoposte ad un 1-hr-1-hr-off (OF) vibrazioni a 200 Hz con aw di 0 ~ 40 pm per 12 ore al giorno per 7 giorni. Costruisce sottoposti a stimoli vibratori sono designati come campioni Vib e quelli culrosso staticamente in camere vibrazioni identiche servono controlli statici (Stat). </li></ol> 5. Valutazioni Biologiche <ol><li> Raccogliere 200 microlitri di cellule di coltura da ciascuna camera ogni altro giorno (giorno 1, 3, 5 e 7) e unire le aliquote dello stesso campione insieme (800 ml ciascuna). </li><li> Quantificare la produzione cellulare di matrice metalloproteinasi-1 (MMP1) e HA utilizzando un kit ELISA MMP1 Sviluppo e acido ialuronico kit ELISA competitivo, rispettivamente seguente procedura dei costruttori. Nel frattempo, saggiare la produzione di precursore solubile elastina seguendo la procedura ELISA precedentemente riportato. 8 </li><li> Al termine dell&#39;ultimo ciclo di vibrazione al giorno 7, rimuovere rapidamente i costrutti cellulari dalle camere vibrazione usando pinzette taglienti e brevemente sciacquare con fosfato freddo salina tamponata (PBS, 4 ° C). </li><li> Per il live colorazione / morto, incubare i costrutti con ioduro di propidio (1:2.000 in PBS) eSyto-13 (1:1000 in PBS) per 5 minuti a temperatura ambiente. Immagine costrutti colorati con un microscopio confocale multiphoton. </li><li> Separatamente, snap-congelare i costrutti cellulari PBS-sciacquati in ghiaccio secco ed estrarre l&#39;RNA cellulare totale seguendo un protocollo riportato in precedenza per l&#39;analisi del gene. 9 </li><li> Verificare la quantità e la qualità del RNA estratto utilizzando un UV-Vis. Campioni di RNA con A260/A280 e A260/A230 rapporti di 1,8-2,2 sono utilizzati per la successiva analisi qPCR. </li><li> Reverse trascrivere RNA (500 ng / campione) in cDNA usando un kit disponibile in commercio trascrizione inversa. </li><li> Eseguire la reazione di PCR su un sistema di rilevamento di sequenze in tempo reale usando una miscela master PCR disponibile in commercio seguendo la procedura precedentemente descritto. 8 </li><li> Analizzare i risultati qPCR utilizzando software commerciale di analisi dei dati qPCR. Per garantire l&#39;affidabilità delle analisi dei dati, più geni di riferimento (YWHAZ, TBP, PPIA) sono impiegati come intcontrolli ernal, e la varianza dei rendimenti specifici di primer viene presa in considerazione. 8 </li></ol>

<ol>
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Ingegneria di successo di tessuti funzionali delle corde vocali in vitro richiede la ricreazione di una piega simile microambiente vocale per mediare i comportamenti di cellule multipotenti. E &#39;generalmente accettato che le strutture dei tessuti o organi riflettono le funzioni che sono chiamati a svolgere. 22 Per i tessuti delle corde vocali, le vibrazioni ad alta frequenza che si verificano durante la fonazione sono proposti per essere importante per la maturazione del tessuto. Nel nostro studio...

La piega vocale umano, composto da uno strato epiteliale, la lamina propria (LP) e il muscolo vocalis, è un tessuto morbido specializzato che converte il flusso d&#39;aria dai polmoni in onde acustiche per la produzione del suono. 1 corde vocali oscillano regolarmente durante la fonazione normale, esibendo ceppi fino al 30% a frequenze fondamentali che vanno 100-300 Hz. 2 Adult corde vocali LP è una struttura composta da un gradiente superficiale (SLP), intermedio (ILP) e una profondità (DLP) strato. Altri gruppi di classificazione l&#39;epitelio e la SLP come lo strato mucosa, e combina la ILP e DLP nel legamento vocale. 3 Lo strato SLP contiene principalmente una matrice amorfa con fibre di collagene scarsamente disperse, mentre il legamento è arricchita con collagene maturo e fibre di elastina per fornire resistenza sufficiente. 4 La struttura e la meccanica di corde vocali neonato variano significativamente dai loro omologhi maturi. Anche se il meccanismos che regolano lo sviluppo delle corde vocali e la maturazione non sono ancora pienamente compresi, evidenze sperimentali ha sottolineato il ruolo di definizione di stress meccanico vocalizzazione-derivati. Diverse condizioni mediche, tra cui l&#39;abuso vocale, infezioni, sostanze chimiche irritanti e procedure chirurgiche, possono danneggiare la piega vocale. Patologie delle corde vocali colpiscono circa 3-9% della popolazione degli Stati Uniti. Metodi di trattamento correnti per i disturbi delle corde vocali sono limitati 5 e un tessuto approccio ingegneristico a base di cellule staminali è emerso come una strategia promettente per il ripristino della funzionalità delle corde vocali. Cellule staminali mesenchimali (MSC) sono una valida alternativa alle corde vocali fibroblasti primari per vocale ingegneria tissutale piega. 6-9 specifica destino delle cellule staminali e lo sviluppo del tessuto successivo sono mediati dalla specifica nicchia risiedono in, cui la condizione meccanica è un fattore vitale. dieci forze meccaniche sono regolatori essenziali di tessuto morfogenesi unnd omeostasi, particolarmente per tessuti che siano periodicamente sottoposti a carico. 11 Da una prospettiva ingegneria dei tessuti, è stato dimostrato che l&#39;esposizione a fisiologicamente rilevanti stimolazioni meccaniche promuove differenziazione delle cellule staminali e tessuto-specifico rimodellamento della matrice. 12-15 Bioreattori coltura tissutale sono progettati per simulare l&#39;ambiente fisiologico desiderato per cellula o tessuto crescita in vitro. Per vocale ingegneria dei tessuti piega, è particolarmente critico per ricreare l&#39;ambiente meccanico delle phonating corde vocali. Una piega ideale bioreattore vocale dovrebbe effettivamente fornire spunti vibranti di cellule in coltura, permettendo il controllo facile su frequenza, ampiezza e la durata delle vibrazioni. Titze e collaboratori hanno realizzato una piega bioreattore vocale (T1 bioreattore) 16 che combina tratto statico ad alta frequenza (20-200 Hz) oscillazioni di stimolare la produzione cellulare di proteine ​​della matrice. Using questo bioreattore, Webb e colleghi 17 hanno studiato gli effetti di 10 giorni, vibrazioni 100 Hz su fibroblasti dermici in coltura in un acido ialuronico (HA) a base di idrogel. Costrutti soggetti a vibrazioni esposte un&#39;elevata espressione di HA sintasi-2 (HAS2), decorin, fibromodulin e matrice metalloproteinasi-1 (MMP1), rispetto ai controlli statici. Gli effetti di stimolazione sono risultate essere dipendente dal tempo. Più di recente, il nostro gruppo 18 montato una piega bioreattore vocale (J1 bioreattore) utilizzando un amplificatore di potenza, un generatore di funzioni, un altoparlante chiuso e una membrana in silicone circonferenzialmente ancorato che trasferisce l&#39;aria oscillante per le cellule attaccate. Fibroblasti prepuzio neonatali coltivate nel bioreattore J1 stati sottoposti a 1 ora di vibrazione a 60, 110 o 300 Hz, con un ceppo in piano fino al 0,05%. I risultati qPCR suggerito che l&#39;espressione di alcuni geni ECM è stata moderatamente alterata in risposta alle varie frequenze vibratoriee ampiezze. Questi disegni bioreattori, mentre intrigante, hanno diverse limitazioni. Ad esempio, il sistema T1 richiede un gran numero di connettori e barre per l&#39;accoppiamento meccanico, limitando le frequenze massima raggiungibile. Inoltre, le cellule possono essere sottoposti a indesiderabile agitazione e fluido meccanica perturbazione che complicano l&#39;interpretazione dei dati. Il bioreattore J1, invece, presenta relativamente bassa efficienza di conversione energetica e non è facile da usare. Inoltre, le vibrazioni si stacca spesso i costrutti cellulari carichi dalla membrana di silicone sottostante. Il J2 vocale piega bioreattore riportato qui, sviluppata sulla base dello stesso principio della versione J1, è ottimizzata per consistenza e riproducibilità. Le vibrazioni-fonazione mimando vengono generati aerodinamicamente in camere dotate di vibrazione individuale, laddove poli fibroso MSC-popolato (ε-caprolattone) (PCL) impalcature sono effectively assicurato. Laser Doppler Vibrometry (LDV) consente all&#39;utente di verificare il profilo vibratorio del gruppo membrana / scaffold. Nella nostra dimostrazione, MSC sono esposti a 200 Hz vibrazioni sinusoidali con (OF) modello 1-hr-1-hr-off per un totale di 12 ore al giorno per 7 giorni. Risposte cellulari agli stimoli vibratori imposte sono indagati sistematicamente. Nel complesso, la piega vocale J2 offre le caratteristiche più user-friendly, che permette studi di coltura cellulare dinamica per essere condotti in un elevato throughput e della moda riproducibile.

<table border="0" cellpadding="0" cellspacing="0" width="853">
	<tbody>
		<tr height="16">
			<td height="16" style="height:17px;width:248px;">silicone elastomer kit</td>
			<td style="width:188px;">Dow Corning</td>
			<td style="width:124px;">Sylgard 184</td>
			<td style="width:293px;">cure the membrane at 100 C for 2 hr</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">PCL</td>
			<td>Sigma Aldrich</td>
			<td>440744-500G</td>
			<td>Mn ~ 80 kDa, dissolve overnight</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">chloroform</td>
			<td>Sigma Aldrich</td>
			<td>C7559-5VL</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">human bone marrow-derived MSCs</td>
			<td>Lonza</td>
			<td>PT-2501</td>
			<td>received with passage 2</td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;">MSC maintenance media</td>
			<td>Lonza</td>
			<td>PT-3001</td>
			<td style="width:293px;">10% FBS in basal media supplemented 
			with L-glutamine, gentamicin and amphotericin</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">Accutase cell dissociation reagent</td>
			<td>Life Technologies</td>
			<td>A11105-01</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">ethanol</td>
			<td>Sigma Aldrich</td>
			<td>E7023-500ML</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">fibronectin</td>
			<td>Sigma Aldrich</td>
			<td>F2006-1MG</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">MMP1 DuoSet ELISA kit</td>
			<td>R&#38;D systems</td>
			<td>DY901</td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">HA ELISA kit</td>
			<td>Echelon Biosciences</td>
			<td>&#160;K-1200&#160;&#160;</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">PBS</td>
			<td>Life Technologies</td>
			<td>14190-136</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">propidium iodide&#160;</td>
			<td>Life Technologies</td>
			<td>P1304MP</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">Syto-13&#160;</td>
			<td>Life Technologies</td>
			<td>S7575</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">QuantiTect reverse transcription kit&#160;</td>
			<td>Qiagen</td>
			<td>205311</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">SYBR Green PCR master mix</td>
			<td>Life Technologies</td>
			<td>4309155</td>
			<td></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;">replacement speaker</td>
			<td style="width:188px;">DAYTON audio 
			(via Parts Express)</td>
			<td>DS90-8</td>
			<td>paper cone, full range (80-13000 Hz), 85dB</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">Ergo Micro torque screwdriver</td>
			<td>Mountz</td>
			<td># 020377</td>
			<td>torque range: 20-120 cN.m</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">stereo speaker selector</td>
			<td>RadioShack</td>
			<td>40-244</td>
			<td>maximum power handling 50 W</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">function generator&#160;</td>
			<td>Agilent&#160;</td>
			<td>33220A</td>
			<td>frequency range 1 &#181;Hz- 20 MHz</td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;">power amplifier&#160;</td>
			<td>PYLE audio</td>
			<td>PylePro PT2400</td>
			<td style="width:293px;">frequency response: 10 Hz-50 kHz, two speaker 
			channels</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">cell culture incubator&#160;</td>
			<td>Thermo Fisher&#160;</td>
			<td>Steri-Cult 3307</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">syringe pump&#160;</td>
			<td>New Era Pump Systems</td>
			<td>NE-300</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">High voltage power supply</td>
			<td>Spellman</td>
			<td>CZE 1000R</td>
			<td>output voltage: 0-30 kV</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">scanning electron microscope&#160;</td>
			<td>JEOL-USA</td>
			<td>JSM-7400F</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">desk gold sputter coater</td>
			<td>Denton Vacuum</td>
			<td>DSK00V-0013</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">Doppler laser vibrometer&#160;</td>
			<td>Polytec</td>
			<td>PDV-100</td>
			<td>non-contact velocity measurement (0-22 kHz)</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">PCR sequence detection system&#160;</td>
			<td>Applied Biosystems</td>
			<td>ABI7300</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">multiphoton confocal microscope</td>
			<td>Zeiss</td>
			<td>Zeiss 510Meta NLO</td>
			<td></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;">UV-VIS Spectrophotometer&#160;</td>
			<td style="width:188px;">NanoDrop Products 
			via Thermo Scientific</td>
			<td>ND-2000</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">VibSoft Data Acquisition Software</td>
			<td>Polytec</td>
			<td></td>
			<td>acquisition bandwidth up to 40 MHz</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">Origin 8.5 data analysis software&#160;</td>
			<td>OriginLab</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">qbasePlus qPCR data analysis software&#160;</td>
			<td>Biogazelle</td>
			<td>V2.3</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">aluminium alloy&#160;</td>
			<td>McMaster-Carr</td>
			<td>Alloy 6061</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">acrylic blocks</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="27">
			<td height="27" style="height:27px;">polycarbonate anti-humidity chamber</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td style="width:293px;">Impact-Resistant&#160;Polycarbonate</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">screws&#160;</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">electronic cable/wire</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">medical grade PVC tubing</td>
			<td>US Plastic Corp.</td>
			<td>Tygon S-50-HL</td>
			<td>clear, biocompatible</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">10 mL syringe&#160;</td>
			<td>Becton Dickinson</td>
			<td>309604</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">21 G blunt ended needle</td>
			<td>Small Parts</td>
			<td>NE-213PL-25</td>
			<td>1-1/2&#34; length</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">Alligator clip adapters&#160;</td>
			<td>RadioShack</td>
			<td>270-354</td>
			<td>fully insulated</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">8 mm biopsy punch</td>
			<td><a href="http://www.sklarcorp.com/ProductListUS.aspx?DepartmentID=10&amp;CategoryID=96">Sklar&#160;Surgical Instruments</a></td>
			<td>96-1152</td>
			<td>sterile, disposable</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">12 mm biopsy punch</td>
			<td>Acuderm (via Fisher Scientific)</td>
			<td style="width:124px;">NC9998681</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">tissue culture flasks</td>
			<td>Corning</td>
			<td></td>
			<td>cell culture treated</td>
		</tr>
	</tbody>
</table>

construction and characterization of a novel vocal fold bioreactor

In vitro engineering of mechanically active tissues requires the presentation of physiologically relevant mechanical conditions to cultured cells. To emulate the dynamic environment of vocal folds, a novel vocal fold bioreactor capable of producing vibratory stimulations at fundamental phonation frequencies is constructed and characterized. The device is composed of a function generator, a power amplifier, a speaker selector and parallel vibration chambers. Individual vibration chambers are created by sandwiching a custom-made silicone membrane between a pair of acrylic blocks. The silicone membrane not only serves as the bottom of the chamber but also provides a mechanism for securing the cell-laden scaffold. Vibration signals, generated by a speaker mounted underneath the bottom acrylic block, are transmitted to the membrane aerodynamically by the oscillating air. Eight identical vibration modules, fixed on two stationary metal bars, are housed in an anti-humidity chamber for long-term operation in a cell culture incubator. The vibration characteristics of the vocal fold bioreactor are analyzed non-destructively using a Laser Doppler Vibrometer (LDV). The utility of the dynamic culture device is demonstrated by culturing cellular constructs in the presence of 200-Hz sinusoidal vibrations with a mid-membrane displacement of 40 &#181;m. Mesenchymal stem cells cultured in the bioreactor respond to the vibratory signals by altering the synthesis and degradation of vocal fold-relevant, extracellular matrix components. The novel bioreactor system presented herein offers an excellent in vitro platform for studying vibration-induced mechanotransduction and for the engineering of functional vocal fold tissues.

Le impalcature PCL fabbricati da elettrofilatura contengono pori interstiziali dimensioni micron e fibre aggrovigliate in modo casuale, con un diametro medio di 4,7 micron (Figura 4A). Con un ingrandimento maggiore, scanalature e nanoscala pori sono visibili su singole fibre (Figura 4B). Rivestimento dei ponteggi con fibronectina migliora idrofilia e facilita l&#39;adesione iniziale delle cellule / diffusione sul patibolo PCL (osservazione inedito). Forme d&...

Watch this Scientific Journal Video about Construction and Characterization of a Novel Vocal Fold Bioreactor at JoVE.com

Construction and Characterization of a Novel Vocal Fold Bioreactor

A novel vocal fold bioreactor capable of delivering physiologically relevant, vibratory stimulation to cultured cells is constructed and characterized. This dynamic culture device, when combined with a fibrous poly(&#949;-caprolactone) scaffold, creates a vocal fold-mimetic environment that modulates the behaviors of mesenchymal stem cells.

Costruzione e caratterizzazione di un Fold bioreattore Novel Vocal

In vitro engineering of mechanically active tissues requires the presentation of physiologically relevant mechanical conditions to cultured cells. To ...

construction-and-characterization-of-a-novel-vocal-fold-bioreactor

Research

JoVE Journal

Bioengineering

9.1K Views.  University of Delaware. A novel vocal fold bioreactor capable of delivering physiologically relevant, vibratory stimulation to cultured cells is constructed and characterized. This dynamic culture device, when combined with a fibrous poly(ε-caprolactone) scaffold, creates a vocal fold-mimetic environment that modulates the behaviors of mesenchymal stem cells.

Video: Construction and Characterization of a Novel Vocal Fold Bioreactor

Engineering Biological-Based Vascular Grafts Using a Pulsatile Bioreactor

Much effort has been devoted to develop and advance the methodology to regenerate functional small-diameter arterial bypasses. In the physiological environment, both mechanical and chemical stimulation are required to maintain the proper development and functionality of arterial vessels1,2.
Bioreactor culture systems developed by our group are designed to support vessel regeneration within a precisely controlled chemo-mechanical environment mimicking that of native vessels. Our bioreactor assembly and maintenance procedures are fairly simple and highly repeatable3,4. Smooth muscle cells (SMCs) are seeded onto a tubular polyglycolic acid (PGA) mesh that is threaded over compliant silicone tubing and cultured in the bioreactor with or without pulsatile stimulation for up to 12 weeks. There are four main attributes that distinguish our bioreactor from some predecessors. 1) Unlike other culture systems that simulate only the biochemical surrounding of native blood vessels, our bioreactor also creates a physiological pulsatile environment by applying cyclic radial strain to the vessels in culture. 2) Multiple engineered vessels can be cultured simultaneously under different mechanical conditions within a controlled chemical environment. 3) The bioreactor allows a mono layer of endothelial cells (EC) to be easily coated onto the luminal side of engineered vessels for animal implantation models. 4) Our bioreactor can also culture engineered vessels with different diameter size ranged from 1 mm to 3 mm, saving the effort to tailor each individual bioreactor to fit a specific diameter size. 
The engineered vessels cultured in our bioreactor resemble native blood vessels histologically to some degree. Cells in the vessel walls express mature SMC contractile markers such as smooth muscle myosin heavy chain (SMMHC)3. A substantial amount of collagen is deposited within the extracellular matrix, which is responsible for ultimate mechanical strength of the engineered vessels5. Biochemical analysis also indicates that collagen content of engineered vessels is comparable to that of native arteries6. Importantly, the pulsatile bioreactor has consistently regenerated vessels that exhibit mechanical properties that permit successful implantation experiments in animal models3,7. Additionally, this bioreactor can be further modified to allow real-time assessment and tracking of collagen remodeling over time, non-invasively, using a non-linear optical microscopy (NLOM)8. To conclude, this bioreactor should serve as an excellent platform to study the fundamental mechanisms that regulate the regeneration of functional small-diameter vascular grafts.

Our group has developed a bioreactor culture system that mimics the physiological pulsatile stresses of the cardiovascular system to regenerate implantable small-diameter vascular grafts.

Ingegneria biologica basata innesti vascolari Utilizzando un bioreattore pulsatile

Much effort has been devoted to develop and advance the methodology to regenerate functional small-diameter arterial bypasses. In the physiological ...

Ricerca

Bioingegneria

Synthetic, Multi-Layer, Self-Oscillating Vocal Fold Model Fabrication

Sound for the human voice is produced via flow-induced vocal fold vibration. The vocal folds consist of several layers of tissue, each with differing material properties 1. Normal voice production relies on healthy tissue and vocal folds, and occurs as a result of complex coupling between aerodynamic, structural dynamic, and acoustic physical phenomena. Voice disorders affect up to 7.5 million annually in the United States alone 2 and often result in significant financial, social, and other quality-of-life difficulties. Understanding the physics of voice production has the potential to significantly benefit voice care, including clinical prevention, diagnosis, and treatment of voice disorders.
Existing methods for studying voice production include in vivo experimentation using human and animal subjects, in vitro experimentation using excised larynges and synthetic models, and computational modeling. Owing to hazardous and difficult instrument access, in vivo experiments are severely limited in scope. Excised larynx experiments have the benefit of anatomical and some physiological realism, but parametric studies involving geometric and material property variables are limited. Further, they are typically only able to be vibrated for relatively short periods of time (typically on the order of minutes).
Overcoming some of the limitations of excised larynx experiments, synthetic vocal fold models are emerging as a complementary tool for studying voice production. Synthetic models can be fabricated with systematic changes to geometry and material properties, allowing for the study of healthy and unhealthy human phonatory aerodynamics, structural dynamics, and acoustics. For example, they have been used to study left-right vocal fold asymmetry 3,4, clinical instrument development 5, laryngeal aerodynamics 6-9, vocal fold contact pressure 10, and subglottal acoustics 11 (a more comprehensive list can be found in Kniesburges et al. 12)
Existing synthetic vocal fold models, however, have either been homogenous (one-layer models) or have been fabricated using two materials of differing stiffness (two-layer models). This approach does not allow for representation of the actual multi-layer structure of the human vocal folds 1 that plays a central role in governing vocal fold flow-induced vibratory response. Consequently, one- and two-layer synthetic vocal fold models have exhibited disadvantages 3,6,8 such as higher onset pressures than what are typical for human phonation (onset pressure is the minimum lung pressure required to initiate vibration), unnaturally large inferior-superior motion, and lack of a "mucosal wave" (a vertically-traveling wave that is characteristic of healthy human vocal fold vibration).
In this paper, fabrication of a model with multiple layers of differing material properties is described. The model layers simulate the multi-layer structure of the human vocal folds, including epithelium, superficial lamina propria (SLP), intermediate and deep lamina propria (i.e., ligament; a fiber is included for anterior-posterior stiffness), and muscle (i.e., body) layers 1. Results are included that show that the model exhibits improved vibratory characteristics over prior one- and two-layer synthetic models, including onset pressure closer to human onset pressure, reduced inferior-superior motion, and evidence of a mucosal wave.

The methodology for fabricating synthetic vocal fold models is described. The models are life-sized and mimic the multi-layer structure of the human vocal folds. Results show the models to self-oscillate at pressures comparable to lung pressure and demonstrate flow-induced vibratory responses that are similar to those of human vocal folds.

Sintetico, Multi-Layer, Auto-oscillante Fabrication Vocal modello Fold

Sound for the human voice is produced via flow-induced vocal fold vibration. The vocal folds consist of several layers of tissue, each with differing ...

Design of a Biaxial Mechanical Loading Bioreactor for Tissue Engineering

We designed a loading device that is capable of applying uniaxial or biaxial mechanical strain to a tissue engineered biocomposites fabricated for transplantation. While the device primarily functions as a bioreactor that mimics the native mechanical strains, it is also outfitted with a load cell for providing force feedback or mechanical testing of the constructs. The device subjects engineered cartilage constructs to biaxial mechanical loading with great precision of loading dose (amplitude and frequency) and is compact enough to fit inside a standard tissue culture incubator. It loads samples directly in a tissue culture plate, and multiple plate sizes are compatible with the system. The device has been designed using components manufactured for precision-guided laser applications. Bi-axial loading is accomplished by two orthogonal stages. The stages have a 50 mm travel range and are driven independently by stepper motor actuators, controlled by a closed-loop stepper motor driver that features micro-stepping capabilities, enabling step sizes of less than 50 nm. A polysulfone loading platen is coupled to the bi-axial moving platform. Movements of the stages are controlled by Thor-labs Advanced Positioning Technology (APT) software. The stepper motor driver is used with the software to adjust load parameters of frequency and amplitude of both shear and compression independently and simultaneously. Positional feedback is provided by linear optical encoders that have a bidirectional repeatability of 0.1 &mu;m and a resolution of 20 nm, translating to a positional accuracy of less than 3 &mu;m over the full 50 mm of travel. These encoders provide the necessary position feedback to the drive electronics to ensure true nanopositioning capabilities. In order to provide the force feedback to detect contact and evaluate loading responses, a precision miniature load cell is positioned between the loading platen and the moving platform. The load cell has high accuracies of 0.15% to 0.25% full scale.

We designed a novel mechanical loading bioreactor that can apply uniaxial or biaxial mechanical strain to a cartilage biocomposite prior to transplantation into an articular cartilage defect.

Progettazione di un biassiale Carico meccanico bioreattore per l&#39;ingegneria tissutale

We  designed a loading device that is capable of applying uniaxial or biaxial  mechanical strain to a tissue engineered biocomposites fabricated for  ...

Operation of a Benchtop Bioreactor

Fermentation systems are used to provide an optimal growth environment for many different types of cell cultures. The ability afforded by fermentors to carefully control temperature, pH, and dissolved oxygen concentrations in particular makes them essential to efficient large scale growth and expression of fermentation products. This video will briefly describe the advantages of the fermentor over the shake flask. It will also identify key components of a typical benchtop fermentation system and give basic instruction on setup of the vessel and calibration of its probes. The viewer will be familiarized with the sterilization process and shown how to inoculate the growth medium in the vessel with culture. Basic concepts of operation, sampling, and harvesting will also be demonstrated. Simple data analysis and system cleanup will also be discussed.

Fermentors are used to increase culture yield and productivity of bioengineered cells. After screening multiple microbial or animal cell culture candidates in shake flasks, the next logical step is to increase the selected culture&#x2019;s biomass with the fermentor. This video demonstrates the setup and operation of a typical benchtop bioreactor system.

Il funzionamento di un bioreattore da banco

Fermentation systems are used to provide an optimal growth environment for many different types of cell cultures. The ability afforded by fermentors to ...

Nonhuman Primate Lung Decellularization and Recellularization Using a Specialized Large-organ Bioreactor

There are an insufficient number of lungs available to meet current and future organ transplantation needs. Bioartificial tissue regeneration is an attractive alternative to classic organ transplantation. This technology utilizes an organ&#39;s natural biological extracellular matrix (ECM) as a scaffold onto which autologous or stem/progenitor cells may be seeded and cultured in such a way that facilitates regeneration of the original tissue. The natural ECM is isolated by a process called decellularization. Decellularization is accomplished by treating tissues with a series of detergents, salts, and enzymes to achieve effective removal of cellular material while leaving the ECM intact. Studies conducted utilizing decellularization and subsequent recellularization of rodent lungs demonstrated marginal success in generating pulmonary-like tissue which is capable of gas exchange in vivo. While offering essential proof-of-concept, rodent models are not directly translatable to human use. Nonhuman primates (NHP) offer a more suitable model in which to investigate the use of bioartificial organ production for eventual clinical use.
The protocols for achieving complete decellularization of lungs acquired from the NHP rhesus macaque are presented. The resulting acellular lungs can be seeded with a variety of cells including mesenchymal stem cells and endothelial cells. The manuscript also describes the development of a bioreactor system in which cell-seeded macaque lungs can be cultured under conditions of mechanical stretch and strain provided by negative pressure ventilation as well as pulsatile perfusion through the vasculature; these forces are known to direct differentiation along pulmonary and endothelial lineages, respectively. Representative results of decellularization and cell seeding are provided.

Whole-organ decellularization produces natural biological scaffolds that may be used for regenerative medicine. The description of a nonhuman primate model of lung regeneration in which whole lungs are decellularized and then seeded with adult stem cells and endothelial cells in a bioreactor that facilitates vascular circulation and liquid media ventilation is presented.

There are an insufficient number of lungs available to meet current and future organ transplantation needs. Bioartificial tissue regeneration is an ...

Investigating the Three-dimensional Flow Separation Induced by a Model Vocal Fold Polyp

The fluid-structure energy exchange process for normal speech has been studied extensively, but it is not well understood for pathological conditions. Polyps and nodules, which are geometric abnormalities that form on the medial surface of the vocal folds, can disrupt vocal fold dynamics and thus can have devastating consequences on a patient&#39;s ability to communicate. Our laboratory has reported particle image velocimetry (PIV) measurements, within an investigation of a model polyp located on the medial surface of an in&#160;vitro driven vocal fold model, which show that such a geometric abnormality considerably disrupts the glottal jet behavior. This flow field adjustment is a likely reason for the severe degradation of the vocal quality in patients with polyps. A more complete understanding of the formation and propagation of vortical structures from a geometric protuberance, such as a vocal fold polyp, and the resulting influence on the aerodynamic loadings that drive the vocal fold dynamics, is necessary for advancing the treatment of this pathological condition. The present investigation concerns the three-dimensional flow separation induced by a wall-mounted prolate hemispheroid with a 2:1 aspect ratio in cross flow, i.e. a model vocal fold polyp, using an oil-film visualization technique. Unsteady, three-dimensional flow separation and its impact of the wall pressure loading are examined using skin friction line visualization and wall pressure measurements.

Vocal fold polyps can disrupt vocal fold dynamics and thus can have devastating consequences on a patient&#39;s ability to communicate. Three-dimensional flow separation induced by a wall-mounted model polyp and its impact on the wall pressure loading are examined using particle image velocimetry, skin friction line visualization, and wall pressure measurements.

Investigare la separazione tridimensionale del flusso indotta da un modello di polipo piega vocale

The fluid-structure energy exchange process for normal speech has been studied extensively, but it is not well understood for pathological conditions. ...

Characterization of Leukocyte-platelet Rich Fibrin, A Novel Biomaterial

Autologous platelet concentrates represent promising innovative tools in the field of regenerative medicine and have been extensively used in oral surgery. Unlike platelet rich plasma (PRP) that is a gel or a suspension, Leukocyte-Platelet Rich Fibrin (L-PRF) is a solid 3D fibrin membrane generated chair-side from whole blood containing no anti-coagulant. The membrane has a dense three dimensional fibrin matrix with enriched platelets and abundant growth factors. L-PRF is a popular adjunct in surgeries because of its superior handling characteristics as well as its suturability to the wound bed. The goal of the study is to demonstrate generation as well as provide detailed characterization of relevant properties of L-PRF that underlie its clinical success.

Leucocyte-Platelet Rich Fibrin (L-PRF) represents an FDA cleared preparation of autologous platelet concentrates that possesses unique fibrin architecture, enriched platelets and abundant growth factors. Here, we present a protocol for chair-side generation of L-PRF as well as evaluate its mechanical properties including uniaxial testing and suture retention strength testing.

Caratterizzazione di leucociti-piastrine Rich fibrina, un biomateriale Novel

Autologous platelet concentrates represent promising innovative tools in the field of regenerative medicine and have been extensively used in oral ...

A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities

A novel reactor design, coined a high density bioreactor (HDBR), is presented for the cultivation and study of high density microbial communities. Past studies have evaluated the performance of the reactor for the removal of COD1 and nitrogen species2-4 by heterotrophic and chemoautotrophic bacteria, respectively. The HDBR design eliminates the requirement for external flocculation/sedimentation processes while still yielding effluent containing low suspended solids. In this study, the HDBR is applied as a photobioreactor (PBR) in order to characterize the nitrogen removal characteristics of an algae-based photosynthetic microbial community. As previously reported for this HDBR design, a stable biomass zone was established with a clear delineation between the biologically active portion of the reactor and the recycling reactor fluid, which resulted in a low suspended solid effluent. The algal community in the HDBR was observed to remove 18.4% of total nitrogen species in the influent. Varying NH4+ and NO3- concentrations in the feed did not have an effect on NH4+ removal (n=44, p=0.993 and n=44, p=0.610 respectively) while NH4+ feed concentration was found to be negatively related with NO3- removal (n=44, p=0.000) and NO3- feed concentration was found to be positively correlated with NO3- removal (n=44, p=0.000). Consistent removal of NH4+, combined with the accumulation of oxidized nitrogen species at high NH4+ fluxes indicates the presence of ammonia- and nitrite-oxidizing bacteria within the microbial community.

A novel reactor design, coined a high density bioreactor (HDBR), is presented for the cultivation and study of high density microbial communities. Here, the HDBR is successfully applied in a photobioreactor (PBR) configuration for the study of nitrogen metabolism by a mixed high density algal community.

Un bioreattore Novel per l&#39;alta densità di coltivazione diverse comunità microbiche

A novel reactor design, coined a high density bioreactor (HDBR), is presented for the cultivation and study of high density microbial communities. Past ...

Construction and Setup of a Bench-scale Algal Photosynthetic Bioreactor with Temperature, Light, and pH Monitoring for Kinetic Growth Tests

The optimal design and operation of photosynthetic bioreactors (PBRs) for microalgal cultivation is essential for improving the environmental and economic performance of microalgae-based biofuel production. Models that estimate microalgal growth under different conditions can help to optimize PBR design and operation. To be effective, the growth parameters used in these models must be accurately determined. Algal growth experiments are often constrained by the dynamic nature of the culture environment, and control systems are needed to accurately determine the kinetic parameters. The first step in setting up a controlled batch experiment is live data acquisition and monitoring. This protocol outlines a process for the assembly and operation of a bench-scale photosynthetic bioreactor that can be used to conduct microalgal growth experiments. This protocol describes how to size and assemble a flat-plate, bench-scale PBR from acrylic. It also details how to configure a PBR with continuous pH, light, and temperature monitoring using a data acquisition and control unit, analog sensors, and open-source data acquisition software.

This paper describes the assembly process and operation of a bench-scale photosynthetic bioreactor that can be used, in conjunction with other methods, to estimate pertinent kinetic growth parameters. This system continuously monitors the pH, light, and temperature using sensors, a data acquisition and control unit, and open-source data acquisition software.

Costruzione e messa a punto di un biotestattore fotosintetico di alghe a bilanciere a banco con monitoraggio della temperatura, della luce e del pH per test di crescita cinetica

The optimal design and operation of photosynthetic bioreactors (PBRs) for microalgal cultivation is essential for improving the environmental and economic ...

Preparation and Characterization of Novel HDL-mimicking Nanoparticles for Nerve Growth Factor Encapsulation

The objective of this article is to introduce preparation and characterization methods for nerve growth factor (NGF)-loaded, high-density, lipoprotein (HDL)-mimicking nanoparticles (NPs). HDLs are endogenous NPs and have been explored as vehicles for the delivery of therapeutic agents. Various methods have been developed to prepare HDL-mimicking NPs. However, they are generally complicated, time consuming, and difficult for industrial scale-up. In this study, one-step homogenization was used to mix the excipients and form the prototype NPs. NGF is a water-soluble protein of 26 kDa. To facilitate the encapsulation of NGF into the lipid environment of HDL-mimicking NPs, protamine USP was used to form an ion-pair complex with NGF to neutralize the charges on the NGF surface. The NGF/protamine complex was then introduced into the prototype NPs. Apolipoprotein A-I was finally coated on the surface of the NPs. NGF HDL-mimicking NPs showed preferable properties in terms of particle size, size distribution, entrapment efficiency, in vitro release, bioactivity, and biodistribution. With the careful design and exploration of homogenization in HDL-mimicking NPs, the procedure was greatly simplified, and the NPs were made scalable. Moreover, various challenges, such as separating unloaded NGF from the NPs, conducting reliable in vitro release studies, and measuring the bioactivity of the NPs, were overcome.

Simple homogenization was used to prepare novel, high-density, lipoprotein-mimicking nanoparticles to encapsulate nerve growth factor. Challenges, detailed protocols for nanoparticle preparation, in vitro characterization, and in vivo studies are described in this article.

Preparazione e caratterizzazione di novel nanoparticelle che imitano HDL per l&#39;incapsulamento del fattore di crescita del nervo

The objective of this article is to introduce preparation and characterization methods for nerve growth factor (NGF)-loaded, high-density, lipoprotein ...