Name: lumican extraction from amniotic membrane and determination of its storage temperature
Uploaded: 2022-10-14T14:30:00
Description: Watch this Scientific Journal Video about Lumican Extraction from Amniotic Membrane and Determination of its Storage Temperature at JoVE.com

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Todos los procedimientos experimentales fueron aprobados por la Junta de Revisión Institucional (Proyecto Nº CEI-2020/06/04). La AM se obtuvo del banco de amnios del Instituto de Oftalmología Conde de Valenciana (de sujetos humanos no identificados), preparado tal como lo describen Chávez-García et al.17.
1. Preparación del extracto de membrana amniótica
<ol><li>Obtenga 100 mg de AM del banco de amnios. NOTA: Según un informe anterior, 50 m...

<ol>
	<li>Jirsova, K., Jones, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amniotic+membrane+in+ophthalmology:+properties,+preparation,+storage+and+indications+for+grafting-a+review.">Amniotic membrane in ophthalmology: properties, preparation, storage and indications for grafting-a review.</a> Cell and Tissue Banking. 18 (2), 193-204 (2017).</li><li>Witherel, C., Yu, T., Concannon, M., Dampier, W., Spiller, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immunomodulatory+effects+of+human+cryopreserved+viable+amniotic+membrane+in+a+pro-inflammatory+environment+in+vitro.">Immunomodulatory effects of human cryopreserved viable amniotic membrane in a pro-inflammatory environment in vitro.</a> Cellular and Molecular Bioengineering. 10 (5), 451-462 (2017).</li><li>Ruiz-Ca&#241;ada, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amniotic+membrane+stimulates+cell+migration+by+modulating+transforming+growth+factor-&#946;+signalling.">Amniotic membrane stimulates cell migration by modulating transforming growth factor-&#946; signalling.</a> Journal of Tissue Engineering and Regenerative Medicine. 12 (3), 808-820 (2017).</li><li>Yeh, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Soluble+lumican+glycoprotein+purified+from+human+amniotic+membrane+promotes+corneal+epithelial+wound+healing.">Soluble lumican glycoprotein purified from human amniotic membrane promotes corneal epithelial wound healing.</a> Investigative Opthalmology &amp; Visual Science. 46 (2), 479 (2005).</li><li>Navas, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Anti-Inflammatory+and+anti-fibrotic+effects+of+human+amniotic+membrane+mesenchymal+stem+cells+and+their+potential+in+corneal+repair.">Anti-Inflammatory and anti-fibrotic effects of human amniotic membrane mesenchymal stem cells and their potential in corneal repair.</a> Stem Cells Translational Medicine. 7 (12), 906-917 (2018).</li><li>Maga&#241;a-Guerrero, F., Dom&#237;nguez-L&#243;pez, A., Mart&#237;nez-Aboytes, P., Buentello-Volante, B., Garfias, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+amniotic+membrane+mesenchymal+stem+cells+inhibit+neutrophil+extracellular+traps+through+TSG-6.">Human amniotic membrane mesenchymal stem cells inhibit neutrophil extracellular traps through TSG-6.</a> Scientific Reports. 7, 12426 (2017).</li><li>Garfias, Y., Zaga-Clavellina, V., Vadillo-Ortega, F., Osorio, M., Jimenez-Martinez, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amniotic+membrane+is+an+immunosuppressor+of+peripheral+blood+mononuclear+cells.">Amniotic membrane is an immunosuppressor of peripheral blood mononuclear cells.</a> Immunological Investigations. 40 (2), 183-196 (2010).</li><li>Koob, T., 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=Biological+properties+of+dehydrated+human+amnion/chorion+composite+graft:+implications+for+chronic+wound+healing.">Biological properties of dehydrated human amnion/chorion composite graft: implications for chronic wound healing.</a> International Wound Journal. 10 (5), 493-500 (2013).</li><li>Miyagi, H., Thomasy, S., Russell, P., Murphy, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+hepatocyte+growth+factor+in+corneal+wound+healing.">The role of hepatocyte growth factor in corneal wound healing.</a> Experimental Eye Research. 166, 49-55 (2018).</li><li>Chen, S., Mienaltowski, M., Birk, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+corneal+stroma+extracellular+matrix+assembly.">Regulation of corneal stroma extracellular matrix assembly.</a> Experimental Eye Research. 133, 69-80 (2015).</li><li>Karamanou, K., Perrot, G., Maquart, F., Br&#233;zillon, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lumican+as+a+multivalent+effector+in+wound+healing.">Lumican as a multivalent effector in wound healing.</a> Advanced Drug Delivery Reviews. 129, 344-351 (2018).</li><li>Theocharis, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell-matrix+interactions:+focus+on+proteoglycan-proteinase+interplay+and+pharmacological+targeting+in+cancer.">Cell-matrix interactions: focus on proteoglycan-proteinase interplay and pharmacological targeting in cancer.</a> FEBS Journal. 281 (22), 5023-5042 (2014).</li><li>Saika, S., 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=Role+of+lumican+in+the+corneal+epithelium+during+wound+healing.">Role of lumican in the corneal epithelium during wound healing.</a> Journal of Biological Chemistry. 275 (4), 2607-2612 (2000).</li><li>Dom&#237;nguez-L&#243;pez, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amniotic+membrane+conditioned+medium+(AMCM)+reduces+inflammatory+response+on+human+limbal+myofibroblast,+and+the+potential+role+of+lumican.">Amniotic membrane conditioned medium (AMCM) reduces inflammatory response on human limbal myofibroblast, and the potential role of lumican.</a> Molecular Vision. 27, 370-383 (2021).</li><li>Vij, N., Roberts, L., Joyce, S., Chakravarti, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lumican+regulates+corneal+inflammatory+responses+by+modulating+Fas-Fas+Ligand+signaling.">Lumican regulates corneal inflammatory responses by modulating Fas-Fas Ligand signaling.</a> Investigative Opthalmology &amp; Visual Science. 46 (1), 88 (2005).</li><li>Mahbod, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amniotic+membrane+extract+preparation:+What+is+the+best+method.">Amniotic membrane extract preparation: What is the best method.</a> Journal of Ophthalmic and Vision Research. 9 (3), 314-319 (2014).</li><li>Ch&#225;vez-Garc&#237;a, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ophthalmic+indications+of+amniotic+membrane+transplantation+in+Mexico:+an+eight+years+Amniotic+Membrane+Bank+experience.">Ophthalmic indications of amniotic membrane transplantation in Mexico: an eight years Amniotic Membrane Bank experience.</a> Cell and Tissue Banking. 17 (2), 261-268 (2015).</li><li>Stenn, K. S., Link, R., Moellmann, G., Madri, J., Kuklinska, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dispase,+a+neutral+protease+from+Bacillus+polymyxa,+is+a+powerful+fibronectinase+and+type+IV+collagenase.">Dispase, a neutral protease from Bacillus polymyxa, is a powerful fibronectinase and type IV collagenase.</a> Journal of Investigative Dermatology. 93 (2), 287-290 (1989).</li><li>Bhatnagar, B. S., Bogner, R. H., Pikal, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Protein+stability+during+freezing:+separation+of+stresses+and+mechanisms+of+protein+stabilization.">Protein stability during freezing: separation of stresses and mechanisms of protein stabilization.</a> Pharmaceutical Development and Technology. 12 (5), 505-523 (2007).</li><li>McClain, A. K., McCarrel, T. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+four+different+freezing+conditions+and+time+in+frozen+storage+on+the+concentration+of+commonly+measured+growth+factors+and+enzymes+in+equine+platelet-rich+plasma+over+six+months.">The effect of four different freezing conditions and time in frozen storage on the concentration of commonly measured growth factors and enzymes in equine platelet-rich plasma over six months.</a> BMC Veterinary Research. 15 (1), 292 (2019).</li><li>Tamhane, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+amniotic+membrane+transplantation+as+an+adjunct+to+medical+therapy+as+compared+with+medical+therapy+alone+in+acute+ocular+burns.">Evaluation of amniotic membrane transplantation as an adjunct to medical therapy as compared with medical therapy alone in acute ocular burns.</a> Ophthalmology. 112 (11), 1963-1969 (2005).</li><li>Shtein, 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=Autologous+serum-based+eye+drops+for+treatment+of+ocular+surface+disease.">Autologous serum-based eye drops for treatment of ocular surface disease.</a> Ophthalmology. 127 (1), 128-133 (2020).</li><li>Shahriari, H., Tokhmehchi, F., Reza, M., Hashemi, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+the+effect+of+amniotic+membrane+suspension+and+autologous+serum+on+alkaline+corneal+epithelial+wound+healing+in+the+rabbit+model.">Comparison of the effect of amniotic membrane suspension and autologous serum on alkaline corneal epithelial wound healing in the rabbit model.</a> Cornea. 27 (10), 1148-1150 (2008).</li><li>Schuerch, K., Baeriswyl, A., Frueh, B., Tappeiner, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficacy+of+amniotic+membrane+transplantation+for+the+treatment+of+corneal+ulcers.">Efficacy of amniotic membrane transplantation for the treatment of corneal ulcers.</a> Cornea. 39 (4), 479-483 (2019).</li><li>Chen, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amniotic+membrane+transplantation+for+persistent+corneal+ulcers+and+perforations+in+acute+fungal+keratitis.">Amniotic membrane transplantation for persistent corneal ulcers and perforations in acute fungal keratitis.</a> Cornea. 25 (5), 564-572 (2006).</li><li>Guo, Q., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+comparison+of+the+effectiveness+between+amniotic+membrane+homogenate+and+transplanted+amniotic+membrane+in+healing+corneal+damage+in+a+rabbit+model.">A comparison of the effectiveness between amniotic membrane homogenate and transplanted amniotic membrane in healing corneal damage in a rabbit model.</a> Acta Ophthalmologica. 89 (4), 315-319 (2011).</li><li>Sabater, A., Perez, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amniotic+membrane+use+for+management+of+corneal+limbal+stem+cell+deficiency.">Amniotic membrane use for management of corneal limbal stem cell deficiency.</a> Current Opinion in Ophthalmology. 28 (4), 363-369 (2017).</li><li>Ahmad, T., 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=Autolysis+of+bovine+skin,+its+endogenous+proteases,+protease+inhibitors+and+their+effects+on+quality+characteristics+of+extracted+gelatin.">Autolysis of bovine skin, its endogenous proteases, protease inhibitors and their effects on quality characteristics of extracted gelatin.</a> Food Chemistry. 265, 1-8 (2018).</li><li>Mullegama, S. V., 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=Nucleic+acid+extraction+from+human+biological+samples.">Nucleic acid extraction from human biological samples.</a> Methods in Molecular Biology. 1897, 359-383 (2019).</li><li>Skog, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+enzymatic+digestion+on+cultured+epithelial+autografts.">The effect of enzymatic digestion on cultured epithelial autografts.</a> Cell Transplantation. 28 (5), 638-644 (2019).</li></ol>

En este estudio, se analizó la presencia de lumican en el AME y su correlación directa con su estabilidad bajo diferentes condiciones de almacenamiento. Curiosamente, cuando se cuantificó la concentración total de proteína en AME, la concentración de proteína aumentó después del almacenamiento. La evidencia sugiere tres mecanismos que podrían cambiar la concentración de proteínas en el almacenamiento congelado: la desnaturalización en frío, la concentración congelada de solutos y el despliegue parcial indu...

Uno de los tratamientos más utilizados para las afecciones corneales es el trasplante de membrana amniótica; Sin embargo, en los últimos años, han surgido nuevas propuestas para utilizar diversos componentes del tejido amniótico como tratamientos alternativos y adyuvantes. Entre los componentes más estudiados de AM se encuentran los obtenidos del extracto de AM (AME)1,2,3,4,5,6,7. AM contiene múltiples factores solubles como proteínas antiangiogénicas, interleucinas (IL), inhibidores tisulares de metaloproteinasas (TIMP), proteínas antiinflamatorias mediadas por TSG-6 que inhiben las trampas extracelulares de neutrófilos, factores de crecimiento: factor de crecimiento epidérmico (EGF), factor de crecimiento transformante (TGF) (alfa y beta), factor de crecimiento de queratinocitos (KGF), factor de crecimiento de hepatocitos (HGF) y lumican, que mantiene la transparencia corneal mediante la regulación de la fibrilogénesisde colágeno 1, 2,3,4,5,6,7,8,9.
Lumican es un pequeño proteoglicano rico en leucina (SLRP), uno de los principales componentes extracelulares de la colagenasa intersticial en la matriz del estroma corneal, responsable de organizar las fibras de colágeno y mantener la transparencia corneal 4,10,11. Los proteoglicanos son moléculas de la matriz extracelular (MEC), que son las principales en la realización de la señalización celular y el mantenimiento de la homeostasis intracelular12. Se ha informado que las proteínas ECM impulsan los procesos celulares de proliferación, diferenciación y migración durante la cicatrización de heridas11.
La evidencia indica la posible participación de lumican en el proceso de reepitelización corneal. Saika et al., en un estudio, demostraron que después de una lesión corneal, lumican podría detectarse en queratocitos corneales entre las primeras 8 h y hasta 3 días después de la lesión. Presentando la mayor concentración de lumicano en el segundo y tercer día, este proteoglicano es posteriormente indetectable en el séptimo día13. Estos datos sugieren la participación de lumican en la activación del proceso de reepitelización corneal. Por otro lado, en otro estudio, se informó que la ausencia de lumicano retrasa la reepitelización; Curiosamente, la adición de Lumican podría acelerar el proceso de reepitelización 4,11,13. Asimismo, un estudio reciente ha reportado que lumican puede modular las funciones inflamatorias de los fibroblastos del limbo corneal14, lo que sugiere un papel para lumican como modulador de la respuesta inflamatoria, antifibrótica y reepitelizante. Del mismo modo, lumican puede modular la respuesta corneal interactuando con moléculas de señalización como Fas-FasL. Además, la ausencia de lumican en un modelo de ratón Lum-/- knockout demostró que la falta de señalización lumican impide una reparación corneal adecuada15.
Principalmente, este método tiene como objetivo demostrar una forma factible y accesible de extraer lumican de AM. Con este ventajoso método de extracción lumicana, es posible obtener concentraciones similares de proteínas, disminuyendo el tiempo de procesamiento y haciéndolo más conveniente para los investigadores en comparación con los estudios previos16. Además, este AME lumican podría usarse como adyuvante para procesos de reparación y reepitelización corneal.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>1 N H2SO4 stop solution</td>
			<td>R&#38;D Systems</td>
			<td>DY994</td>
			<td></td>
		</tr>
		<tr>
			<td>100 &#956;L micropipette</td>
			<td>Eppendorf</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>1000 &#956;L micropipette</td>
			<td>Eppendorf</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>15 mm Petri dish</td>
			<td>Symlaboratorios</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>18 G Needle (1.2 mm x 40 mm)</td>
			<td>BD Becton Dickinson&#160;</td>
			<td>305211</td>
			<td></td>
		</tr>
		<tr>
			<td>2 mL microcentrifuge tube</td>
			<td>Eppendorf</td>
			<td>Z606340</td>
			<td></td>
		</tr>
		<tr>
			<td>20 mL plastic syringe&#160;</td>
			<td>BD Becton Dickinson&#160;</td>
			<td>302562</td>
			<td></td>
		</tr>
		<tr>
			<td>20 &#956;L micropipette</td>
			<td>Eppendorf</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>20-200 &#956;L micropipette</td>
			<td>Eppendorf</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>5 mL microcentrifuge tube</td>
			<td>Eppendorf</td>
			<td>30119401</td>
			<td></td>
		</tr>
		<tr>
			<td>96-well microplate</td>
			<td>SARSTEDT</td>
			<td>821581</td>
			<td></td>
		</tr>
		<tr>
			<td>Aluminum foil</td>
			<td>N/A</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Amniotic membrane</td>
			<td>Instituto de Oftalmologia Conde de Valenciana Amnion Bank</td>
			<td></td>
			<td>100 mg</td>
		</tr>
		<tr>
			<td>Balanced salt solution</td>
			<td>Bausch + Lomb</td>
			<td>BSS-403802</td>
			<td></td>
		</tr>
		<tr>
			<td>Beaker</td>
			<td>N/A</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>BioRender&#160;</td>
			<td>BioRender</td>
			<td></td>
			<td>figures design&#160;</td>
		</tr>
		<tr>
			<td>Compact Rocker</td>
			<td>BioRad</td>
			<td>970822DD</td>
			<td>Mod. 5202SD-BIO</td>
		</tr>
		<tr>
			<td>complete, EDTA-free, Protease inhibitor 
			cocktail tablets</td>
			<td>Roche</td>
			<td>11 873 580 001</td>
			<td>Protease Inhibitor</td>
		</tr>
		<tr>
			<td>Daiggner vortex Genie 2</td>
			<td>A.Daigger &#38; Co. , INC</td>
			<td>22220A</td>
			<td></td>
		</tr>
		<tr>
			<td>Dispase II</td>
			<td>Gibco</td>
			<td>17105-041</td>
			<td></td>
		</tr>
		<tr>
			<td>ELISA plate spectrometer</td>
			<td>Thermo Labsystems&#160;</td>
			<td>35401106</td>
			<td>Multiscan</td>
		</tr>
		<tr>
			<td>Freezer</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>GraphPad Prism&#160;</td>
			<td>GraphPad Software, Inc</td>
			<td>version 9</td>
			<td>statistical analysis and graphic program&#160;</td>
		</tr>
		<tr>
			<td>Human lumican DuoSet ELISA kit</td>
			<td>R&#38;D Systems</td>
			<td>DY2846-05</td>
			<td>includes human Lumican capture antibody</td>
		</tr>
		<tr>
			<td>Incubator&#160;</td>
			<td>Forma Scientific&#160;</td>
			<td>3326 S/N 36481-7002</td>
			<td></td>
		</tr>
		<tr>
			<td>Inverted light Microscope</td>
			<td>Olympus&#160;</td>
			<td>6A13921</td>
			<td>to confirm de-epithelialization&#160; Mod.CK2</td>
		</tr>
		<tr>
			<td>Laminar flow hood</td>
			<td>Forma Scientific&#160;</td>
			<td>14753-567</td>
			<td>Mod.1184</td>
		</tr>
		<tr>
			<td>Liquid nitrogen</td>
			<td>N/A</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Mortar</td>
			<td>N/A</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Multi-channel pipettor</td>
			<td>Eppendorf</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Nitrogen Tank</td>
			<td>Thermo Scientific</td>
			<td></td>
			<td>Mod. Biocan 20</td>
		</tr>
		<tr>
			<td>Paper towels</td>
			<td>N/A</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Phosphate-buffered saline</td>
			<td>R&#38;D Systems</td>
			<td>DY006</td>
			<td></td>
		</tr>
		<tr>
			<td>Pierce Modified Lowry Protein Assay Kit</td>
			<td>Thermo Scientific</td>
			<td>23240</td>
			<td></td>
		</tr>
		<tr>
			<td>Plate sealers</td>
			<td>R&#38;D Systems</td>
			<td>DY992</td>
			<td></td>
		</tr>
		<tr>
			<td>Reagent diluent</td>
			<td>R&#38;D Systems</td>
			<td>DY995</td>
			<td>1% BSA in PBS, pH 7.2-7.4, 0.2 &#956;m filtered</td>
		</tr>
		<tr>
			<td>Refrigerated centrifuge</td>
			<td>centurion scientific Ltd&#160;</td>
			<td>15877</td>
			<td>Mod. K2015R</td>
		</tr>
		<tr>
			<td>Rubber policeman cell scraper</td>
			<td>NEST</td>
			<td>710001</td>
			<td>for mechanical de-epithelialization</td>
		</tr>
		<tr>
			<td>Scalpel knife</td>
			<td>Braun</td>
			<td>BB521</td>
			<td>No. 10 or 21</td>
		</tr>
		<tr>
			<td>Streptavidin-HRP 40-fold concentrated&#160;</td>
			<td>R&#38;D Systems</td>
			<td>part 893975</td>
			<td></td>
		</tr>
		<tr>
			<td>Substrate tetramethylbenzidine (TMB) solution</td>
			<td>R&#38;D Systems</td>
			<td>DY999</td>
			<td></td>
		</tr>
		<tr>
			<td>Toothed tweezers</td>
			<td>Invent Germany</td>
			<td>6b</td>
			<td>inox&#160;</td>
		</tr>
		<tr>
			<td>Ultrapure water</td>
			<td>PISA</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Wash buffer</td>
			<td>R&#38;D Systems</td>
			<td>WA126</td>
			<td>0.05% Tween 20 in PBS, pH 7.2-7.4</td>
		</tr>
	</tbody>
</table>

lumican extraction from amniotic membrane and determination of its storage temperature

Lumican es un pequeño proteoglicano rico en leucina en la membrana amniótica humana (AM) que promueve la epitelización corneal y la organización de las fibras de colágeno, manteniendo la transparencia corneal. En el presente trabajo, se propone un método de extracción de proteínas de AM para obtener lumican. Además, se evalúa la estabilidad de lumicano en el extracto AM (AME) almacenado a diferentes temperaturas y períodos de tiempo. 100 mg de AM fueron descongelados y desepitelizados mecánicamente. La AM desepitelizada se congeló y trituró hasta obtener un polvo fino, que se solubilizó con 2,5 mL de tampón salino con inhibidores de la proteasa y se centrifugó para la extracción de proteínas. El sobrenadante se recolectó y almacenó a -20 °C, 4 °C y temperatura ambiente (RT) durante 6, 12, 20 y 32 días. Posteriormente, lumican se cuantificó en cada AME. Esta técnica permite un protocolo accesible y adquirible para la extracción lumican de AM. La concentración de Lumican se vio afectada por el tiempo de almacenamiento y las condiciones de temperatura. Lumican en el AME de 12 días almacenado a -20 °C y 4 °C fue significativamente mayor que otros AME. Esta extracción lumica podría ser útil para desarrollar tratamientos y soluciones farmacéuticas. Se necesitan estudios adicionales para determinar los usos de AME lumican en el proceso de reepitelización y cicatrización de heridas.

Los resultados se informan como el valor medio ± la desviación estándar (DE). Se realizaron pruebas t de Student y análisis de varianza (ANOVA). Los valores de p < 0,05 se consideraron estadísticamente significativos. El análisis estadístico se realizó utilizando software estadístico (ver Tabla de materiales).
La cantidad total de proteína en el AME se vio afectada por el tiempo y las condiciones de almacenamiento. La concentración de proteína bas...

Watch this Scientific Journal Video about Lumican Extraction from Amniotic Membrane and Determination of its Storage Temperature at JoVE.com

Lumican Extraction from Amniotic Membrane and Determination of its Storage Temperature

El presente protocolo describe la extracción de lumican de la membrana amniótica (AM) y sus condiciones de almacenamiento como extracto de AM (AME) a -20 °C, 4 °C y temperatura ambiente (RT) durante 6, 12, 20 y 32 días para cuantificar sus proteínas y la concentración de lumicano.

Extracción de Lumican de la membrana amniótica y determinación de su temperatura de almacenamiento

Lumican is a small leucine-rich proteoglycan in the human amniotic membrane (AM) that promotes corneal epithelialization and the organization of collagen ...

Este método tiene como objetivo demostrar una técnica sencilla para la extracción de proteínas, útil para la obtención de proteínas abundantes y otros factores. Esta técnica podría utilizarse para extraer otros factores y proteínas presentes en la membrana amniótica y también, para obtener proteínas de otras fuentes como animales y tejidos vegetales. Comience descongelando 100 miligramos de la membrana amniótica obtenida del banco de amnios.Una vez descongelada, agregue 10 mililitros de la solución salina equilibrada estéril a una placa de Petri y lave la membrana durante dos minutos. Luego, retire la solución salina balanceada utilizada en un vaso de precipitados y repita el proceso hasta que no haya rastro de medio de glicerol visible en la placa de Petri. A continuación, agregue 10 mililitros de dispasa II a la membrana e incube a 37 grados centígrados y 5% de dióxido de carbono durante 30 minutos.Al final de la incubación, realice una desepitelización mecánica con un raspador de células de policía de goma. Luego, visualice la membrana bajo un microscopio invertido para confirmar la desepitelización. A continuación, lave la membrana amniótica desepitelizada con la solución salina equilibrada estéril como se demostró anteriormente, y colóquela en un tubo de microcentrífuga de dos mililitros.Luego, sumerja el tubo que contiene la membrana en nitrógeno líquido durante 40 minutos. Después de la congelación con nitrógeno líquido, muele manualmente la membrana durante dos o tres minutos en un mortero, preenfriado a menos 85 grados centígrados, hasta que se obtenga un polvo fino. A continuación, agregue 2,5 mililitros de solución inhibidora de la proteasa y solubilice la membrana finamente pulverizada.Limpie las paredes de mortero con la ayuda de un cuchillo de bisturí y transfiera la mezcla a un tubo de cinco mililitros. Vórtice el tubo durante 30 segundos. Luego, homogeneice la mezcla de tejido centrifugando primero a 34 G durante 20 minutos a cuatro grados centígrados, e inmediatamente centrifugando nuevamente a 3, 360 G durante 20 minutos a cuatro grados centígrados.Al final de la centrifugación, recoja el sobrenadante, que es el extracto de membrana amniótica, en un tubo nuevo. Luego, alícuota 0.7 mililitros en un tubo de microcentrífuga diferente de dos mililitros para varios puntos de tiempo y temperaturas. La cantidad total de proteína y la concentración de lumicano en el extracto de membrana amniótica se vieron afectadas por el tiempo y las condiciones de almacenamiento.La concentración de proteína basal fue similar entre todos los extractos de membrana amniótica. Sin embargo, se observó una concentración de proteína significativamente alta en el extracto almacenado durante 32 días a cuatro grados centígrados y 20 días a menos 20 grados centígrados. Lumican en el extracto de membrana amniótica fue significativamente mayor en la muestra almacenada durante un período de 12 días en comparación con las muestras almacenadas durante 30, 20 y seis días a cuatro y menos 20 grados centígrados.Estos resultados sugirieron que el tiempo de almacenamiento y la temperatura adecuados para lograr la mayor concentración de lumicano es de 12 días a menos 20 grados centígrados. Ejerza el máximo cuidado mientras conecta a tierra la membrana amniótica congelada. La conexión a tierra debe ser suave, ya que podría caerse del mortero.Se necesitan estudios adicionales para determinar el papel del extracto de membrana amniótica lumican en las células epiteliales corneales y para determinar la dosis ideal de lumican para la reepitelización corneal.

lumican-extraction-from-amniotic-membrane-determination-its-storage

Research

JoVE Journal

Medicine

Technique of Subnormothermic Ex Vivo Liver Perfusion for the Storage, Assessment, and Repair of Marginal Liver Grafts

The success of liver transplantation has resulted in a dramatic organ shortage. In most transplant regions 20-30% of patients on the waiting list for liver transplantation die without receiving an organ transplant or are delisted for disease progression. One strategy to increase the donor pool is the utilization of marginal grafts, such as fatty livers, grafts from older donors, or donation after cardiac death (DCD). The current preservation technique of cold static storage is only poorly tolerated by marginal livers resulting in significant organ damage. In addition, cold static organ storage does not allow graft assessment or repair prior to transplantation.
These shortcomings of cold static preservation have triggered an interest in warm perfused organ preservation to reduce cold ischemic injury, assess liver grafts during preservation, and explore the opportunity to repair marginal livers prior to transplantation. The optimal pressure and flow conditions, perfusion temperature, composition of the perfusion solution and the need for an oxygen carrier has been controversial in the past.
In spite of promising results in several animal studies, the complexity and the costs have prevented a broader clinical application so far. Recently, with enhanced technology and a better understanding of liver physiology during ex vivo perfusion the outcome of warm liver perfusion has improved and consistently good results can be achieved.
This paper will provide information about liver retrieval, storage techniques, and isolated liver perfusion in pigs. We will illustrate a) the requirements to ensure sufficient oxygen supply to the organ, b) technical considerations about the perfusion machine and the perfusion solution, and c) biochemical aspects of isolated organs.

Technique of Subnormothermic Ex Vivo Liver Perfusion for the Storage, Assessment, and Repair of Marginal Liver Grafts

Marginal grafts, such as fatty livers, grafts from older donors, or livers retrieved after cardiac death (DCD) tolerate conventional, cold static storage only poorly. We developed a novel model of subnormothermic ex vivo liver perfusion for preservation, assessment, and repair of marginal liver grafts prior to transplantation.

Técnica de Subnormothermic<em&gt; Ex Vivo</em&gt; Perfusión hepática para el Almacenamiento, Evaluación y Reparación de marginales injertos hepáticos

The success of liver transplantation has resulted in a dramatic organ shortage. In most transplant regions 20-30% of patients on the waiting list for ...

Investigación

Medicina

Modeling Encephalopathy of Prematurity Using Prenatal Hypoxia-ischemia with Intra-amniotic Lipopolysaccharide in Rats

Encephalopathy of prematurity (EoP) is a term that encompasses the central nervous system (CNS) abnormalities associated with preterm birth. To best advance translational objectives and uncover new therapeutic strategies for brain injury associated with preterm birth, preclinical models of EoP must include similar mechanisms of prenatal global injury observed in humans and involve multiple components of the maternal-placental-fetal system. Ideally, models should produce a similar spectrum of functional deficits in the mature animal and recapitulate multiple aspects of the pathophysiology. To mimic human systemic placental perfusion defects, placental underperfusion and/or chorioamnionitis associated with pathogen-induced inflammation in early preterm birth, we developed a model of prenatal transient systemic hypoxia-ischemia (TSHI) combined with intra-amniotic lipopolysaccharide (LPS). In pregnant Sprague Dawley rats, TSHI via uterine artery occlusion on embryonic day 18 (E18) induces a graded placental underperfusion defect associated with increasing CNS damage in the fetus. When combined with intra-amniotic LPS injections, placental inflammation is increased and CNS damage is compounded with associated white matter, gait and imaging abnormalities. Prenatal TSHI and TSHI+LPS prenatal insults meet several of the criteria of an EoP model including recapitulating the intrauterine insult, causing loss of neurons, oligodendrocytes and axons, loss of subplate, and functional deficits in adult animals that mimic those observed in children born extremely preterm. Moreover, this model allows for the dissection of inflammation induced by divergent injury types.

Encephalopathy of prematurity encompasses the central nervous system abnormalities associated with injury from preterm birth. This report describes a clinically relevant rat model of in utero transient systemic hypoxia-ischemia and intra-amniotic lipopolysaccharide administration (LPS) that mimics chorioamnionitis, and the related impact of infectious stimuli and placental underperfusion on CNS development.

Modelado Encefalopatía del Prematuro El uso prenatal hipoxia-isquemia con lipopolisacárido intraamniótica en ratas

Encephalopathy of prematurity (EoP) is a term that encompasses the central nervous system (CNS) abnormalities associated with preterm birth. To best ...

Using an Ingestible Telemetric Temperature Pill to Assess Gastrointestinal Temperature During Exercise

Exercise results in an increase in core body temperature (Tc), which may reduce exercise performance and eventually can lead to the development of heat-related disorders. Therefore, accurate measurement of Tc during exercise is of great importance, especially in athletes who have to perform in challenging ambient conditions. In the current literature a number of methods have been described to measure the Tc (esophageal, external tympanic membrane, mouth or rectum). However, these methods are suboptimal to measure Tc during exercise since they are invasive, have a slow response or are influenced by environmental conditions. Studies described the use of an ingestible telemetric temperature pill as a reliable and valid method to assess gastrointestinal temperature (Tgi), which is a representative measurement of Tc. Therefore, the goal of this study was to provide a detailed description of the measurement of Tgi using an ingestible telemetric temperature pill. This study addresses important methodological factors that must be taken into account for an accurate measurement. It is recommended to read the instructions carefully in order to ensure that the ingestible telemetric temperature pill is a reliable method to assess Tgi at rest and during exercise.

This study describes an accurate, reliable and non-invasive technique to continuously measure gastrointestinal temperature during exercise. The ingestible telemetric temperature pill is suitable to measure gastrointestinal temperature in laboratory settings as well as in field based settings.

El uso de una temperatura píldora ingerible telemétrico para evaluar la temperatura gastrointestinal durante el ejercicio

Exercise results in an increase in core body temperature (Tc), which may reduce exercise performance and eventually can lead to the development of ...

Esophageal Heat Transfer for Patient Temperature Control and Targeted Temperature Management

Controlling patient temperature is important for a wide variety of clinical conditions. Cooling to normal or below normal body temperature is often performed for neuroprotection after ischemic insult (e.g. hemorrhagic stroke, subarachnoid hemorrhage, cardiac arrest, or other hypoxic injury). Cooling from febrile states treats fever and reduces the negative effects of hyperthermia on injured neurons. Patients are warmed in the operating room to prevent inadvertent perioperative hypothermia, which is known to cause increased blood loss, wound infections, and myocardial injury, while also prolonging recovery time. There are many reported approaches for temperature management, including improvised methods that repurpose standard supplies (e.g., ice, chilled saline, fans, blankets) but more sophisticated technologies designed for temperature management are typically more successful in delivering an optimized protocol. Over the last decade, advanced technologies have developed around two heat transfer methods: surface devices (water blankets, forced-air warmers) or intravascular devices (sterile catheters requiring vascular placement). Recently, a novel device became available that is placed in the esophagus, analogous to a standard orogastric tube, that provides efficient heat transfer through the patient&#39;s core. The device connects to existing heat exchange units to allow automatic patient temperature management via a servo mechanism, using patient temperature from standard temperature sensors (rectal, Foley, or other core temperature sensors) as the input variable. This approach eliminates vascular placement complications (deep venous thrombosis, central line associated bloodstream infection), reduces obstruction to patient access, and causes less shivering when compared to surface approaches. Published data have also shown a high degree of accuracy and maintenance of target temperature using the esophageal approach to temperature management. Therefore, the purpose of this method is to provide a low-risk alternative method for controlling patient temperature in critical care settings.

This study presents a novel method to provide efficient patient temperature control for cooling or warming patients. A single use, triple lumen device is placed into the esophagus, analogous to a standard orogastric tube, and connects to existing heat exchange units to perform automatic patient temperature management.

Transferencia de calor del esófago para el Control de temperatura del paciente y gestión de la temperatura objetivo

Controlling patient temperature is important for a wide variety of clinical conditions. Cooling to normal or below normal body temperature is often ...

Microelectrode Impalement Method to Record Membrane Potential from a Cannulated Middle Cerebral Artery

Membrane potential (Vm) of vascular smooth muscle cells determines vessel tone and thus blood flow to an organ. Changes in the expression and function of ion channels and electrogenic pumps that regulate Vm in disease conditions could potentially alter Vm, vascular tone, and blood flow. Thus, a basic understanding of electrophysiology and the methods necessary to accurately record Vm in healthy and diseased states are essential. This method will allow modulating Vm using different pharmacological agents to restore Vm. Although there are several methods, each with its advantages and disadvantages, this article provides protocols to record Vm from cannulated resistance vessels such as the middle cerebral artery using the microelectrode impalement method. Middle cerebral arteries are allowed to gain myogenic tone in a myograph chamber, and the vessel wall is impaled using high resistance microelectrodes. The Vm signal is collected through an electrometer, digitized, and analyzed. This method provides an accurate reading of the Vm of a vessel wall without damaging the cells and without changing the membrane resistance.

The primary goal of this article is to provide details of how to record membrane potential (Vm) from the middle cerebral artery using the microelectrode impalement method. The cannulated middle cerebral artery is equilibrated to gain myogenic tone, and the vessel wall is impaled using high resistance microelectrodes.

Método de empalamiento de microelectrodos para registrar el potencial de la membrana a partir de una arteria cerebral media cannulada

Membrane potential (Vm) of vascular smooth muscle cells determines vessel tone and thus blood flow to an organ. Changes in the expression and function of ...

Chemiluminescence-based Assays for Detection of Nitric Oxide and its Derivatives from Autoxidation and Nitrosated Compounds

Nitric oxide (NO) activity in vivo is the combined results of its direct effects, the action of its derivatives generated from NO autoxidation, and the effects of nitrosated compounds. Measuring NO metabolites is essential to studying NO activity both at vascular levels and in other tissues, especially in the experimental settings where exogenous NO is administered. Ozone-based chemiluminescence assays allow precise measurements of NO and NO metabolites in both fluids (including plasma, tissue homogenates, cell cultures) and gas mixtures (e.g., exhaled breath). NO reacts with ozone to generate nitrogen dioxide in an excited state. The consequent light emission allows photodetection and the generation of an electric signal reflecting the NO content of the sample. Aliquots from the same sample can be used to measure specific NO metabolites, such as nitrate, nitrite, S-nitrosothiols, and iron-nitrosyl complexes. In addition, NO consumed by cell-free hemoglobin is also quantified with chemiluminescence analysis. An illustration of all these techniques is provided.

Here, we present protocols for detecting nitric oxide and its biologically relevant derivatives using chemiluminescence-based assays with high sensitivity.

Ensayos basados en quimioluminiscencia para la detección de óxido nítrico y sus derivados de la autoxidación y compuestos nitrosados

Nitric oxide (NO) activity in vivo is the combined results of its direct effects, the action of its derivatives generated from NO autoxidation, and the ...

Dynamic Continuous Blood Extraction from Rat Heart via Noninvasive Microdialysis Technique

Dynamic analysis of blood components is of great importance in understanding cardiovascular diseases and their related diseases, such as myocardial infarction, arrhythmia, atherosclerosis, cardiogenic pulmonary edema, pulmonary embolism, and cerebral embolism. At the same time, it is urgent to break through the continuous heart blood sampling technique in live rats to evaluate the effectiveness of distinctive ethnic medicine therapy. In this study, a blood microdialysis probe was implanted in the right jugular vein of rats in a precise and noninvasive surgical procedure. Cardiac blood samples were then collected at a rate of 2.87 nL/min to 2.98 mL/min by connecting to an online microdialysis sample collection system. Even more momentously, the acquired blood samples can temporarily be stored in microdialysis containers at 4 &#176;C. The microdialysis-based online continuous blood collection program from rat heart has greatly guaranteed the quality of blood samples, advancing and invigorating the scientific rationality of the research on systemic cardiovascular diseases and evaluating ethnomedicine therapy from the perspective of hematology.

Dynamic Continuous Blood Extraction from Rat Heart via Noninvasive Microdialysis Technique

The present protocol describes a simple and efficient method for the real-time and dynamic collection of rat heart blood using the microdialysis technique.

Extracción dinámica continua de sangre del corazón de rata mediante una técnica de microdiálisis no invasiva

Dynamic analysis of blood components is of great importance in understanding cardiovascular diseases and their related diseases, such as myocardial ...

Extracción económica de ADN de diatomeas con un kit modificado

Extraction of Diatom DNA from Water Samples and Tissues

Diatom testing is an essential auxiliary means in forensic practice to determine whether the corpse drowned in water and to infer the drowning location. Diatom testing is also an important research content in the field of the environment and plankton. The diatom molecular biology testing technology, which focuses on diatom DNA as the primary research object, is a new method of diatom testing. Diatom DNA extraction is the basis of diatom molecular testing. At present, the kits commonly used for diatom DNA extraction are expensive, which increases the cost of carrying out related research. Our laboratory improved the general whole blood genomic DNA rapid extraction kit and obtained a satisfactory diatom DNA extraction effect, thus providing an alternative economical and affordable DNA extraction solution based on glass beads for related research. The diatom DNA extracted using this protocol could satisfy many downstream applications, such as PCR and sequencing.

Autor destacado: Pruebas de diatomeas para el examen forense de ahogamiento 

This article describes a protocol for diatom DNA extraction using a modified common DNA extraction kit.

Extracción de ADN de diatomeas a partir de muestras de agua y tejidos

Diatom testing is an essential auxiliary means in forensic practice to determine whether the corpse drowned in water and to infer the drowning location. ...