Agradecemos al Dr. Jeffrey Caplan para su formación y asesoramiento sobre la imagen confocal. También agradecemos al Keck Microscopía Electrónica y Laboratorios Dr. Chaoying Ni para la asistencia SEM. Este trabajo está financiado por los Institutos Nacionales de Salud (NIDCD, R01DC008965 y R01DC011377). ABZ reconoce NSF Integrativa de Posgrado Formación y programa (IGERT) para la financiación de la investigación de prácticas.

1. Asamblea biorreactor (vídeo 1) <ol><li> Hacer un molde de aluminio (matriz circular + pin espaciador) con las dimensiones internas y externas predeterminadas (Figura 1). </li><li> Usando el molde desde el paso 1.1, fabricar una membrana de silicona (diámetro: 42 mm, espesor: 1,5 mm, Figura 1) con un manguito arraigada (diámetro: 12 mm, espesor ~ 0,25 mm, en forma de por el pasador de espaciador en la Figura 1) en el medio utilizando un kit de elastómero de silicona disponible en el mercado. </li><li> Hacer un par de bloques de acrílico (Figura 2 (4, 5)) con una abertura circular (diámetro: 24 mm) en el centro, grabar la parte superior (1,8 cm de espesor) e inferior (0,9 cm de espesor) bloques con aristas coincidentes y ranuras . 10 </li><li> Emparedado de la membrana de silicona entre los bloques de acrílico pareadas. Fije el conjunto con cuatro tornillos de las esquinas con un destornillador de torsión micro ajustado a una fuerza constante (35 cN · m). Como resultado, un estanca al agua, 24 mm de ancho y 18 mm de cámara profunda vibración es creada (Figura 2C). </li><li> Montar un &quot;rango extendido mini-woofer 3 (Figura 2D, 8 Ω/20 W) por debajo de la cámara de la vibración a través de otro conjunto de tornillos de las esquinas en el bloque de acrílico inferior. En este punto, un módulo de vibración individual está montado. </li><li> Replicar siete módulos de vibraciones adicionales. Coloque cuatro de ellos a uno de dos barras de aluminio fijos (40 cm x 10 cm x 2,5 cm), colocando las bases de altavoz en orificios circulares uniformemente espaciados (diámetro: 7 cm, espesor: 2 cm) cortadas en los bares. Estabilizar cada altavoz mediante la inserción de un tornillo a través del lado de la barra de aluminio en cada agujero circular. </li><li> Controlar individualmente los altavoces por un selector de altavoces. Conectar altavoces individuales al selector uniendo cables a las entradas positiva y negativa en el cuerpo de altavoz a continuación a las salidas correspondientes en el selector. El selector del altavoz permite que la señal de tque generador de funciones, después de pasar a través de un amplificador de potencia, para alcanzar los ocho altavoces al mismo tiempo (Figura 2E). </li><li> Coloque las dos matrices de cámara, el selector de altavoces y componentes electrónicos asociados en un recinto anti-humedad. Casa todo el conjunto en una incubadora de cultivo celular comercial. </li><li> Alimentar a los cables principales (a través de un tubo de PVC de grado médico) que conecta el amplificador de potencia y el selector de altavoz a través del conjunto de filtro en la parte posterior de la incubadora. </li></ol> 2. Fabricación de la estructura y Caracterización <ol><li> Disolver gránulos de PCL en cloroformo a una concentración de 15% en peso. Cargar la solución en una jeringa de 10 ml tapado con una aguja de punta roma 21 G. </li><li> Bloquee la jeringa en una bomba de inyección programable y ajustar la velocidad de flujo a 1 ml / hr. </li><li> Coloque el colector de aluminio cubierto de aluminio a través de la aguja en posición horizontal, con una aguja de distancia de punta a colector de ~ 18 cm. </li><li> Sujete el alli positivoGator clip a la media de la aguja, y la pinza de cocodrilo de tierra al colector de aluminio, a continuación, establecer el voltaje en la fuente de alimentación de alta tensión de 15 kV. PRECAUCIÓN: alta tensión, mantener la distancia de la aguja. </li><li> Convertir secuencialmente en la bomba de jeringa y la fuente de alimentación; rápidamente limpiar / remover la solución de polímero residual que rodea la punta de la aguja con una toalla de papel seca antes de jets fibra estable y Taylor cono 19 se forman. </li><li> Dejar que las fibras se acumulan en el colector de Al con un grosor de ~ 250-300 micras (~ 7 h bajo las condiciones de hilado actuales). Guarde los andamios resultantes en un desecador de vacío durante 1-2 días para eliminar cualquier disolvente residual. </li><li> Imagen de los andamios, recubrieron por deposición con oro, utilizando un microscopio electrónico de barrido para mostrar la morfología de la fibra consistente. 10 </li></ol> 3. Asamblea biorreactor y Caracterización <ol><li> Haz un disco cilíndrico (diámetro: 8 mm) con cuatro brazos (longitud: 2mm) fuera de la estera como hilado-PCL (Figura 2A) por primera usando un punzón de biopsia de 12 mm de diámetro para cortar el diámetro exterior del disco. A continuación, utilice un segundo, 8 mm punzón de biopsia para hacer cuatro muescas 2 mm de largo espaciados uniformemente alrededor de la hoja circular de anotar dónde están las armas para cortar. Después de anotar con el punzón de 8 mm, utilizar una cuchilla de escalpelo para cortar los bordes de los brazos hacia afuera. Inserte el andamio en la ranura de la membrana de silicona a través de los brazos extendidos (Video 1). Acoplar el andamio insertado presionando suavemente la superficie con unas pinzas de cabeza plana. </li><li> Coloque un pedazo pequeño de fina lámina de aluminio (8 mm x 2 mm, de forma ortogonal, Figura 2B) al cadalso PCL para ayudar a la reflexión del láser. </li><li> Asegure la membrana de silicona / PCL andamio montado (como se detalla en el paso 1.4) en la cámara de vibración. Añadir 1,5 ml de agua en la cámara con el fin de hidratar el andamio PCL antes de la vibración. </li><li> Usando el generador de funciones, introducir señal de vibraciónALS (por ejemplo, 200 Hz ondas sinusoidales con una tensión de pico a pico, Vpp, de 0,1 V) a la cámara de acrílico intercalada. Utilice un voltímetro para medir con precisión el voltaje en cada entrada del altavoz. Nota: la lectura Vpp desde el generador de funciones será diferente de la tensión de la eventual entrega al altavoz. </li><li> Montar la LDV de un solo punto y asegurar la cabeza del sensor láser de fibra óptica en un trípode cabeza pan-tilt. Ángulo de la cabeza del sensor de manera que está apuntando perpendicular al tablero de la mesa. Conectar el cabezal del sensor LDV al módulo de adquisición de datos a través de cable coaxial entonces el módulo a la computadora portátil a través de USB. </li><li> Enfocar el haz de láser perpendicularmente a diversos puntos predeterminados en la membrana de silicona (Figura 2B y Figura 3). </li><li> Utilizando el software de adquisición de datos, registrar el desplazamiento mediados de membrana. Haga clic en &quot;Configuración de adquisición&quot; en el menú &quot;Opciones&quot;; a continuación, cambiar el modo de medición a &quot;FFT221;. A continuación, haga clic en la &quot;medición continua&quot; en la barra de herramientas principal haga clic en el pico que se forma en la frecuencia elegida (Figura 6D) para registrar el desplazamiento. </li><li> Trazar el desplazamiento mediados de membrana normal (w 0) como una función de la posición relativa a través del sustrato. Construir un mapa de colores 3D del perfil vibratoria superficie usando Origen software de análisis de datos 8.5. </li></ol> 4. Vibratorio Cultivo Celular <ol><li> MSC derivadas de médula ósea humana Sub-cultura en frascos de cultivo de tejidos T150 en una densidad de siembra inicial de 4.000-5.000 células / cm 2 en MSC medio de mantenimiento. </li><li> Después de 7-8 días de cultivo celular (hasta ~ 85% de confluencia), trypsinize las células con un reactivo de disociación celular como accutase, contar utilizando un hemocitómetro, se centrifuga (440 g durante 5 min), y volver a suspender el sedimento celular en fresca MSC medios de mantenimiento a una concentración de 4,5 x 10 6 células / ml. </li><li> Sumerja el Scaffo PCLld en el 70% de etanol O / N. Después de evaporar el disolvente, exponer ambos lados del andamio para germicida de luz UV (254 nm) para 5-8 min. </li><li> Remojar el andamio PCL en una solución de fibronectina 20 mg / ml a 37 ° C durante 1 hora. Inserte el andamiaje de fibronectina recubierto en la membrana de silicona. Montar el biorreactor como se detalla en el paso 1. </li><li> Distribuir 40 l de la suspensión celular de manera uniforme en el cadalso PCL garantizado. Permitir que las células se unan durante 1-1,5 h antes de la adición de un adicional de 1,5 ml de medio fresco a la cámara de vibración. </li><li> Cultura al cadalso PCL-MSC cargado estáticamente durante 3 días y actualizar los medios de comunicación al término de la cultura estática. </li><li> Imponer regímenes de vibración seleccionados para los constructos celulares. Nota: A modo de ejemplo, las células se someten a una 1-hr-a-1-hr-desactivación (OF) de vibración a 200 Hz con aw 0 de ~ 40 m durante 12 horas al día durante un máximo de 7 días. Las construcciones sometidas a estímulos vibratorios se designan como muestras Vib y esas culturojo estáticamente en cámaras de vibraciones idénticas servir como controles estáticos (Stat). </li></ol> 5. Evaluaciones biológicas <ol><li> Recoger 200 l de medios de cultivo celular a partir de cada cámara de cada dos días (días 1, 3, 5, y 7) y agrupar las partes alícuotas de la misma muestra juntos (800 l cada uno). </li><li> Cuantificar la producción celular de la matriz metaloproteinasa-1 (MMP1) y HA mediante un kit de ELISA MMP1 Desarrollo y un kit de ELISA competitiva ácido hialurónico, respectivamente, siguiendo el procedimiento de los fabricantes. Mientras tanto, el ensayo de la producción de precursor de la elastina soluble en siguiendo el procedimiento de ELISA se informó anteriormente. 8 </li><li> Al finalizar el último ciclo de la vibración en el día 7, eliminar rápidamente los constructos celulares de las cámaras de vibración utilizando pinzas afiladas y enjuagarlos con frío tampón fosfato salino (PBS, 4 ° C) brevemente. </li><li> Para la tinción vivo / muerto, incubar las construcciones con yoduro de propidio (1:2.000 en PBS) ySyto-13 (1:1.000 en PBS) simultáneamente durante 5 min a TA. Imagen de las construcciones teñidos con un microscopio confocal multifotónica. </li><li> Por separado, complemento congelar los constructos celulares se enjuagaron con PBS en hielo seco y se extrae el ARN celular total después de un protocolo se informó anteriormente para el análisis de genes. 9 </li><li> Verificar, la cantidad y la calidad del ARN extraído usando un espectrofotómetro UV-Vis. Las muestras de ARN con A260/A280 y A260/A230 proporciones de 1.8 a 2.2 se utilizan para el análisis de qPCR posterior. </li><li> Transcribir inversamente el ARN (500 ng / muestra) en ADNc usando un kit de transcripción inversa disponibles comercialmente. </li><li> Realizar la reacción de PCR en un sistema de detección de secuencias en tiempo real usando una mezcla maestra de PCR disponible comercialmente siguiendo el procedimiento detallado anteriormente. 8 </li><li> Analizar los resultados qPCR utilizando software comercial para el análisis de datos qPCR. Para garantizar la fiabilidad de los análisis de datos, múltiples genes de referencia (YWHAZ, PDD, PPIA) se emplean como intcontroles ernal, y la varianza de las eficiencias de cebadores específicos se tiene en cuenta. 8 </li></ol>

<ol>
	<li>Titze, I. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanical-Stress+in+Phonation.">Mechanical-Stress in Phonation.</a> J. Voice. 8, 99-105 (1994).</li><li>Titze, I. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+the+Relation+Between+Subglottal+Pressure+and+Fundamental-Frequency+in+Phonation.">On the Relation Between Subglottal Pressure and Fundamental-Frequency in Phonation.</a> J. Acoust. Soc. Am. 85, 901-906 (1989).</li><li>Gray, S. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cellular+physiology+of+the+vocal+folds.">Cellular physiology of the vocal folds.</a> Otolaryngol. Clin. N. Am. 33, 679-698 (2000).</li><li>Thibeault, S. L., Gray, S. D., Bless, D. M., Chan, R. W., Ford, C. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Histologic+and+rheologic+characterization+of+vocal+fold+scarring.">Histologic and rheologic characterization of vocal fold scarring.</a> J. Voice. 16, 96-104 (2002).</li><li>Hansen, J. K., Thibeault, S. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Current+understanding+and+review+of+the+literature:+Vocal+fold+scarring.">Current understanding and review of the literature: Vocal fold scarring.</a> J. Voice. 20, 110-120 (2006).</li><li>Pittenger, M. F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multilineage+potential+of+adult+human+mesenchymal+stem+cells.">Multilineage potential of adult human mesenchymal stem cells.</a> Science. 284, 143-147 (1999).</li><li>Hanson, S. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+Mesenchymal+Stem+Cells+From+Human+Vocal+Fold+Fibroblasts.">Characterization of Mesenchymal Stem Cells From Human Vocal Fold Fibroblasts.</a> Laryngoscope. 120, 546-551 (2010).</li><li>Tong, Z., Duncan, R. L., Jia, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modulating+the+behaviors+of+mesenchymal+stem+cells+via+the+combination+of+high-frequency+vibratory+stimulations+and+fibrous+scaffolds.">Modulating the behaviors of mesenchymal stem cells via the combination of high-frequency vibratory stimulations and fibrous scaffolds.</a> Tissue Eng. Part A. 19, 1862-1878 (2013).</li><li>Tong, Z., Sant, S., Khademhosseini, A., Jia, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Controlling+the+Fibroblastic+Differentiation+of+Mesenchymal+Stem+Cells+Via+the+Combination+of+Fibrous+Scaffolds+and+Connective+Tissue+Growth+Factor.">Controlling the Fibroblastic Differentiation of Mesenchymal Stem Cells Via the Combination of Fibrous Scaffolds and Connective Tissue Growth Factor.</a> Tissue Eng. Part A. 17, 2773-2785 (2011).</li><li>Jones, D. L., Wagers, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=No+place+like+home:+anatomy+and+function+of+the+stem+cell+niche.">No place like home: anatomy and function of the stem cell niche.</a> Nat. Rev. Mol. Cell Biol. 9, 11-21 (1038).</li><li>Wang, J. H., Thampatty, B. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanobiology+of+Adult+and+Stem+Cells.">Mechanobiology of Adult and Stem Cells.</a> Int. Rev. of Cell Mol. Biol. 271, 301-346 (2008).</li><li>Doroski, D. M., Levenston, M. E., Temenoff, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cyclic+tensile+culture+promotes+fibroblastic+differentiation+of+marrow+stromal+cells+encapsulated+in+poly+(ethylene+glycol)-based+hydrogels.">Cyclic tensile culture promotes fibroblastic differentiation of marrow stromal cells encapsulated in poly (ethylene glycol)-based hydrogels.</a> Tissue Eng. Part A. 16, 3457-3466 (2010).</li><li>Kim, B. S., Nikolovski, J., Bonadio, J., Mooney, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cyclic+mechanical+strain+regulates+the+development+of+engineered+smooth+muscle+tissue.">Cyclic mechanical strain regulates the development of engineered smooth muscle tissue.</a> Nat. Biotechnol. 17, 979-983 (1999).</li><li>Webb, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cyclic+strain+increases+fibroblast+proliferation,+matrix+accumulation,+and+elastic+modulus+of+fibroblast-seeded+polyurethane+constructs.">Cyclic strain increases fibroblast proliferation, matrix accumulation, and elastic modulus of fibroblast-seeded polyurethane constructs.</a> J. Biomech. 39, 1136-1144 (2006).</li><li>Kim, Y. J., Sah, R. L. Y., Grodzinsky, A. J., Plaas, A. H. K., Sandy, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanical+Regulation+of+Cartilage+Biosynthetic+Behavior+-+Physical+Stimuli..">Mechanical Regulation of Cartilage Biosynthetic Behavior - Physical Stimuli..</a> Arch. Biochem. Biophys. 311, 1-12 (1994).</li><li>Titze, I. 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=Design+and+validation+of+a+bioreactor+for+engineering+vocal+fold+tissues+under+combined+tensile+and+vibrational+stresses.">Design and validation of a bioreactor for engineering vocal fold tissues under combined tensile and vibrational stresses.</a> J. Biomech. 37, 1521-1529 (2004).</li><li>Kutty, J. K., Webb, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vibration+stimulates+vocal+mucosa-like+matrix+expression+by+hydrogel-encapsulated+fibroblasts.">Vibration stimulates vocal mucosa-like matrix expression by hydrogel-encapsulated fibroblasts.</a> J. Tissue Eng. Regen. Med. 4, 62-72 (2010).</li><li>Farran, A. J. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+and+Characterization+of+a+Dynamic+Vibrational+Culture+System.">Design and Characterization of a Dynamic Vibrational Culture System.</a> J. Tissue Eng. Regen. Med. , (2011).</li><li>Reneker, D. H., Yarin, A. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrospinning+jets+and+polymer+nanofibers.">Electrospinning jets and polymer nanofibers.</a> Polymer. 49, 2387-2425 (2008).</li><li>Wang, Y., Theobald, P., Tyrer, J., Lepper, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+application+of+scanning+vibrometer+in+mapping+ultrasound+fields.">The application of scanning vibrometer in mapping ultrasound fields.</a> J. Phys.: Conf. Ser. 1, 167-173 (2004).</li><li>Brown, W. S., Morris, R. J., Hollien, H., Howell, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Speaking+Fundamental-Frequency+Characteristics+as+a+Function+of+Age+and+Professional.">Speaking Fundamental-Frequency Characteristics as a Function of Age and Professional.</a> J. Voice. 5, 310-315 (1991).</li><li>Ingber, D. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cellular+mechanotransduction:+putting+all+the+pieces+together+again.">Cellular mechanotransduction: putting all the pieces together again.</a> Faseb J. 20, 811-827 (2006).</li><li>Titze, I. 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=Design+and+validation+of+a+bioreactor+for+engineering+vocal+fold+tissues+under+combined+tensile+and+vibrational+stresses.">Design and validation of a bioreactor for engineering vocal fold tissues under combined tensile and vibrational stresses.</a> J. Biomech. 37, 1521-1529 (2004).</li><li>Moore, J., Thibeault, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Insights+Into+the+Role+of+Elastin+in+Vocal+Fold+Health+and+Disease.">Insights Into the Role of Elastin in Vocal Fold Health and Disease.</a> J. Voice. 26, 269-275 (2012).</li><li>Thibeault, S. L., Bless, D. M., Gray, S. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Interstitial+protein+alterations+in+rabbit+vocal+fold+with+scar.">Interstitial protein alterations in rabbit vocal fold with scar.</a> J. Voice. 17, 377-383 (2003).</li><li>Branski, R. C., Verdolini, K., Sandulache, V., Rosen, C. A., Hebda, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vocal+fold+wound+healing:+A+review+for+clinicians.">Vocal fold wound healing: A review for clinicians.</a> J. Voice. 20, 432-442 (2006).</li><li>Clark, I. A., Swingler, T. E., Sampieri, C. L., Edwards, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+regulation+of+matrix+metalloproteinases+and+their+inhibitors.">The regulation of matrix metalloproteinases and their inhibitors.</a> Int. J. Biochem. Cell B. 40, 1362-1378 (2008).</li><li>Silver, F. H., Horvath, I., Foran, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Viscoelasticity+of+the+vessel+wall:+The+role+of+collagen+and+elastic+fibers.">Viscoelasticity of the vessel wall: The role of collagen and elastic fibers.</a> Crit. Rev. Biomed. Eng. 29, 279-301 (2001).</li><li>Kutty, J. K., Webb, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tissue+Engineering+Therapies+for+the+Vocal+Fold+Lamina+Propria.">Tissue Engineering Therapies for the Vocal Fold Lamina Propria.</a> Tissue Eng. Part B: Rev. 15, 249-262 (2009).</li></ol>

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Ingeniería con éxito de los tejidos de las cuerdas vocales funcionales in vitro requiere la recreación de un microambiente veces como vocal para mediar en el comportamiento de las células multipotentes. En general se acepta que las estructuras de tejidos u órganos reflejan las funciones que se requieren para llevar a cabo. 22 Para los tejidos de las cuerdas vocales, se proponen las vibraciones de alta frecuencia que se producen durante la fonación a ser importante para la maduración de los tej...

El pliegue vocal humano, compuesto por una capa epitelial, la lámina propia (LP) y el músculo vocal, es un tejido blando especializada que convierte el flujo de aire de los pulmones a las ondas acústicas para la producción de sonido. 1 Las cuerdas vocales oscilan regularmente durante la fonación normal, exhibiendo cepas de hasta 30% en las frecuencias fundamentales que van desde 100 hasta 300 Hz. 2 adultos vocal LP veces es una estructura compuesta de un gradiente superficial (SLP), un compuesto intermedio (ILP) y un (DLP) capa profunda. Otros grupos de clasificación del epitelio y la SLP como la capa mucosa, y combina la ILP y DLP en el ligamento vocal. 3 La capa SLP contiene principalmente una matriz amorfa con fibras colágenas escasamente dispersas, mientras que el ligamento está enriquecida con colágeno maduro y las fibras de elastina para proporcionar suficiente resistencia. 4 La estructura y la mecánica de las cuerdas vocales recién nacidos varían significativamente de sus contrapartes maduros. Aunque el mecanismos que regulan el desarrollo de las cuerdas vocales y la maduración aún no se entienden completamente, la evidencia experimental ha señalado a los roles que definen a los esfuerzos mecánicos derivados de la vocalización. Varias condiciones médicas, incluyendo el abuso de la voz, infecciones, irritantes químicos y procedimientos quirúrgicos, pueden dañar la cuerda vocal. Trastornos de las cuerdas vocales afectan a un estimado de 3.9% de la población de los EE.UU.. Los métodos actuales de tratamiento para los trastornos de las cuerdas vocales se limitan 5 y un enfoque de la ingeniería de tejidos a base de células madre se ha convertido en una estrategia prometedora para restaurar la función de las cuerdas vocales. Las células madre mesenquimales (MSC) son una alternativa adecuada a los fibroblastos de las cuerdas vocales principales para la ingeniería de tejidos vocal fold. 6-9 especificación del destino de células madre y el desarrollo del tejido posterior son mediados por el nicho específico que residen en, de los cuales la condición mecánica es un factor vital. 10 Las fuerzas mecánicas son reguladores esenciales de tejidos morfogénesis unND homeostasis, sobre todo para los tejidos que están sometidos rutinariamente a la carga. 11 Desde una perspectiva de la ingeniería de tejidos, se ha demostrado que la exposición a estímulos mecánicos fisiológicamente relevantes promueve la diferenciación de células madre y remodelación de la matriz específica de tejido. 12-15 Biorreactores de cultivo de tejidos están diseñados para simular el entorno fisiológico deseado para la célula o tejido crecimiento in vitro. Para vocal ingeniería tisular veces, es especialmente crítico para recrear el ambiente mecánico de las cuerdas vocales fonación. Un biorreactor de las cuerdas vocales ideal debe cumplir efectivamente las señales vibratorias a células de cultivo, permitiendo el control fácil sobre la frecuencia, amplitud y duración de las vibraciones. Titze y compañeros de trabajo idearon un biorreactor vocal veces (biorreactor T1) 16 que combina estiramiento estático con alta frecuencia (20-200 Hz) oscilaciones para estimular la producción celular de proteínas de la matriz. Usíng este biorreactor, Webb y colegas 17 estudiaron los efectos de 10 días-, 100-Hz vibraciones en fibroblastos dérmicos cultivados en un ácido hialurónico (HA) a base de hidrogel. Las construcciones sometidas a vibraciones mostraron una elevada expresión de HA sintasa-2 (HAS2), decorina, fibromodulina y la metaloproteinasa de matriz-1 (MMP-1), relativa a los controles estáticos. Se encontró que los efectos estimulantes de ser dependiente del tiempo. Más recientemente, nuestro grupo de 18 reunió a un biorreactor de las cuerdas vocales (biorreactor J1) con un amplificador de potencia, un generador de funciones, un altavoz cerrado y una membrana de silicona circunferencialmente ancladas que transfiere el aire oscilante a las células unidas. Fibroblastos de prepucio neonatal cultivados en el biorreactor J1 se sometieron a 1 hora de vibración a 60, 110 o 300 Hz, con una cepa en el plano de hasta 0,05%. Los resultados qPCR sugirieron que la expresión de algunos genes ECM fue alterado moderadamente en respuesta a las múltiples frecuencias vibratoriasy amplitudes. Estos diseños de biorreactores, mientras intrigante, tienen varias limitaciones. Por ejemplo, el sistema T1 requiere un gran número de conectores y barras de acoplamiento mecánico, la limitación de las frecuencias máximas alcanzables. Por otra parte, las células pueden ser sometidos a agitación y indeseable de fluido perturbación mecánica que complican la interpretación de los datos. El biorreactor J1, por otro lado, exhibe relativamente baja eficiencia de conversión de energía y no es fácil de usar. Además, la vibración con frecuencia separa los constructos de células cargado de la membrana de silicona subyacente. El J2 biorreactor de las cuerdas vocales informado aquí, diseñado basado en el mismo principio que la versión J1, está optimizado para la consistencia y reproducibilidad. Las vibraciones de fonación que imitan se generan aerodinámicamente en cámaras de vibración montados individualmente cuando poli fibrosa poblada-MSC (ε-caprolactona) (PCL) andamios son effectively asegurado. Láser Doppler vibrometría (LDV) permite al usuario verificar el perfil vibratorio del conjunto de membrana / andamio. En nuestra demostración, las MSC se exponen a 200 Hz vibraciones sinusoidales con una (DE) patrón 1-hr-a-1-hr-off para un total de 12 horas al día durante 7 días. Las respuestas celulares a las señales vibratorias impuestas son investigadas sistemáticamente. En general, el pliegue vocal J2 ofrece la mayor cantidad de funciones fáciles de usar, lo que permite estudios de cultivo celular dinámico para llevarse a cabo en un alto rendimiento y la moda reproducible.

<table border="0" cellpadding="0" cellspacing="0" width="853">
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			<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.

Los andamios PCL fabricadas por electrospinning contienen poros intersticiales clasificadas micrón y fibras enredadas al azar con un diámetro medio de 4,7 micras (Figura 4). A un aumento superior, ranuras nanoescala y poros son visibles en fibras individuales (Figura 4B). El recubrimiento de los andamios con fibronectina mejora hidrofilicidad y facilita la adhesión celular inicial / difusión en el cadalso PCL (observación no publicada). Formas de onda s...

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.

Construcción y caracterización de un Fold biorreactor Novela 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 vistas.  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.

La ingeniería biológica basada en los injertos vasculares El uso de un biorreactor pulsátil

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

Investigación

Bioingeniería

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.

Sintético, multi-capa, auto-oscilante Fabricación Vocal Modelo Doble

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.

Diseño de un Carga mecánica Biaxial biorreactor para Ingeniería de Tejidos

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.

La operación de un biorreactor de sobremesa

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.

Investigación De La Separación De Flujo Tridimensional Inducida Por Un Pólipo Modelo De Pliegue Vocal

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.

Caracterización de los leucocitos-plaquetas Rich fibrina, una novela de Biomateriales

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 biorreactor Novela de alta densidad de cultivo de diversas comunidades microbianas

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.

Construcción y configuración de un biorreactor fotosintético de algas a escala de banco con control de temperatura, luz y pH para pruebas de crecimiento cinético

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.

Preparación y caracterización de nuevas nanopartículas que imitan las HDL para la encapsulación del factor de crecimiento nervioso

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