Wellcome Trust Harçlar nazik (hibe sayısı 085245/Z/08/Z) kabul edilmektedir. Nottingham Nanoteknoloji ve Nanobilim Merkezi nazik Bu ekipman finansmanı için Raman sistemine erişim veren ve East Midlands Kalkınma Ajansı için kabul edilmektedir.

<ol>
	<li>Hook, A. L., Anderson, D. G., Langer, R., Williams, P., Davies, M. C., Alexander, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+throughput+methods+applied+in+biomaterial+development+and+discovery.">High throughput methods applied in biomaterial development and discovery.</a> Biomaterials. 31, 187-198 (2010).</li><li>Anderson, D. G., Levenberg, S., Langer, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanoliter-scale+synthesis+of+arrayed+biomaterials+and+application+to+human+embryonic+stem+cells.">Nanoliter-scale synthesis of arrayed biomaterials and application to human embryonic stem cells.</a> Nature Biotechnology. 22, 863-866 (2004).</li><li>Mei, Y., Saha, K., Bogatyrev, S. R., Yang, J., Hook, A. L., Kalcioglu, Z. I., Cho, S. W., Mitalipova, M., Pyzocha, N., Rojas, F., Van Vliet, K. J., Davies, M. C., Alexander, M. R., Langer, R., Jaenisch, R., Anderson, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Combinatorial+development+of+biomaterials+for+clonal+growth+of+human+pluripotent+stem+cells.">Combinatorial development of biomaterials for clonal growth of human pluripotent stem cells.</a> Nature Materials. 9, 768-778 (2010).</li><li>Pernagallo, S., Wu, M., Gallagher, M. P., Bradley, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Colonising+new+frontiers-microarrays+reveal+biofilm+modulating+polymers.">Colonising new frontiers-microarrays reveal biofilm modulating polymers.</a> Journal of Materials Chemistry. 21, 96-101 (2011).</li><li>Yang, J., Mei, Y., Hook, A. L., Taylor, M., Urquhart, A. J., Bogatyrev, S. R., Langer, R., Anderson, D. G., Davies, M. C., Alexander, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polymer+surface+functionalities+that+control+human+embryoid+body+cell+adhesion+revealed+by+high+throughput+surface+characterization+of+combinatorial+material+microarrays.">Polymer surface functionalities that control human embryoid body cell adhesion revealed by high throughput surface characterization of combinatorial material microarrays.</a> Biomaterials. 31, 8827-8838 (2010).</li><li>Urquhart, A. J., Anderson, D. G., Taylor, M., Alexander, M. R., Langer, R., Davies, M. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+throughput+surface+characterisation+of+a+combinatorial+material+library.">High throughput surface characterisation of a combinatorial material library.</a> Advanced Materials. 19, 2486-2491 (2007).</li><li>Taylor, M., Urquhart, A. J., Zelzer, M., Davies, M. C., Alexander, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Picoliter+water+contact+angle+measurement+on+polymers.">Picoliter water contact angle measurement on polymers.</a> Langmuir. 23, 6875-6878 (2007).</li><li>Urquhart, A. J., Taylor, M., Anderson, D. G., Langer, R., Davies, M. C., Alexander, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=TOF-SIMS+analysis+of+a+576+micropatterned+copolymer+array+to+reveal+surface+moieties+that+control+wettability.">TOF-SIMS analysis of a 576 micropatterned copolymer array to reveal surface moieties that control wettability.</a> Analytical Chemistry. 80, 135-142 (2008).</li><li>Hook, A. L., Yang, J., Chen, X., Roberts, C. J., Mei, Y., Anderson, D. G., Langer, R., Alexander, M. R., Davies, M. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Acrylate+polymers+with+hydro-responsive+topography.">Acrylate polymers with hydro-responsive topography.</a> Soft Matter. 7, 7194-9197 (2011).</li><li>Pernagallo, S., Unciti-Broceta, A., Diaz-Mochon, J. J., Bradley, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Deciphering+cellular+morphology+and+biocompatibility+using+polymer+microarrays.">Deciphering cellular morphology and biocompatibility using polymer microarrays.</a> Biomedical Materials. 3, (2008).</li></ol>

Biz ifşa etmek başka bir şey var.

Polimer mikroarray&#39;ler başarıyla biyolojik bir tahlil roman polimer taraması yüzlerce yeni malzemelerin tespiti için kullanılır ve daha sonra kullanışlı cihazlar kadar ölçeklendirilebilir &#39;hit&#39; malzemelerin belirlenmesi edilmiştir. Bu durumda, tarif edilen yüzey karakterizasyonu biyolojik tahlil sonra kullanılabilecektir ve sadece vurulmasından malzemeler ile ilgili daha fazla ayrıntılı olarak, bu malzemeler incelemek. HTSC Bu yaklaşımı kullanan deneyci mevcut değilse, bu stratejinin ilgi çekici olabilir. Ancak, tam olarak biyolojik-malzeme etkileşimleri öncesinde sonradan genel yapı-fonksiyon eğilimleri gözlemlemek için kullanılabilir HTSC metodolojiler kullanarak biyolojik testler için analiz edilmelidir malzemeler yüzlerce tüm dizi çalışma polimer mikroarrayler kullanmak. İletişim baskı çivili içinde serbestçe yukarı ve aşağı kaydırarak metal pim dayanır. Pim ve pim tutucu temizliği çok önemlidir p sağlanması olmasıdırrinting başarıyla gerçekleşir ve titizlikle yapılmalıdır. Bir baskı çivili içindeki pimi uygun hareket çalıştırın başlamadan önce mevcut hiçbir monomerler ile bir prova yaparak test edilebilir. Pin hareketi tekrarlanabilir elde edilene kadar temizleme aşamasından devam etmelidir. Önemli bir düşünce, monomer karışımın dizayn gitmek gerekir. Kolayca polimerlerin bir kombinatoryal kütüphane üretmek için, kopolimerler yüzlerce farklı oranlarda birkaç monomer karışımı ile oluşur. Bu, bir cam slayt geometri için uygun olan bir 24 x 24 dizi formları olarak Tipik olarak 576 üye kütüphaneler üretmek. En basit yöntem, bir 2:1 oranında pairwise az 24 monomer karışımı olan en kombinatoryal boşluk araştıran bir kombinatoryal kütüphanesi üretmek için. Alternatif olarak, dizi içinde kompozisyon gradyanlar dahil optimum monomer bileşimleri d olmasını sağlar trendleri gözlemler, etkinleştirme için yararlıdıretermined. 22, bu monomerlerin bir örnek ardışık olarak 1 ile 6 ve ikinci bileşenler ile seyreltilen bir ko-monomer karışımı içinde, ilk bileşen olarak kullanılabilir gibi. 5 dilüsyonları kullanılması durumunda, örneğin, 90:10, 75:25, 50:50, 25:75 ve 10:90 oranları, birinci ve ikinci bileşenlerin karıştırılması, bu 488 eşsiz kopolimer çözüm neden olacaktır. 576 toplam getirmek için, genellikle önemli bir referans örnek sokulabilir kullanılan monomerlerin homopolimerleri çoğaltır. 576 monomer çözeltilerinden 2 384 kuyucuğu akar edilmelidir. Robot programlama için bu monomerlerin konumu açısından iki özdeş plakalar daha kolaydır, böylece, bu da monomer çözümleri iki plaka arasında eşit olarak bölünmüş olmalıdır. Zaman önemli bir kısmı çok kanallı bir pipet kullanılarak kaynak plakaları hazırlanmasında kaydedilebilir ve kaynak plakaları tasarımı çok kanallı bir pipet kullanılarak faydalanmak için tespit edilmesi gerekmektedir. &lt;/ P&gt; Dizilerin otomatik HTSC ulaşmak için nokta pozisyonu başarıyla karakterizasyonu aparatı ile aynı hizada olmalıdır. Tipik bir akrilat dizi adım 500-1000 mikron ve polimer spot çapı 300 mikron. En çok XY aşamaları 10 um altında bir çözünürlüğe sahip, böylece, doğru boyut örnek konumlandırma yazılım için girildikten sonra dizisi pozisyonları güvenilir bir şekilde ulaşmak için yüzey karakterizasyonu cihaz için yeterli tolerans vardır. Otomatik konumlandırma sınırlaması aslında dizinin doğru baskı yapıyor. Bu baskı sahnede substrat hareketini önlemek için önemlidir doğru yazdırmayı garantilemek için ya uygun bir slayt boyutları (bir ABD ve AB standart slayt boyutunu ikisinin de geçerli olduğunu unutmayın) ile birlikte vakum emme veya Kıskaç kullanarak. TOF-SIMS numuneler üzerinde herhangi bir kirlenme göreceksiniz son derece yüzeyi hassas bir tekniktir. Böylece, upmost dikkat edilmelidiryüzey ile temas önlemek için. Örnekler sadece ele, ancak ilgi yüzeyi temiz eldiven (tercihen polietilen) ile temizlenmiş ve taze cımbız ile temas etmediği için gerekmektedir. Biz genellikle kloroform ve hekzan ile yıkayın. Ölçümler için önceki örnek depolama en çok ayrı slaytlar tutan bir numune tutucu içinde yapılabilir, örneğin 5 slayt tutucu ya da tutucu 20 kayar. Olduğu Diziler olduğunu, birçok biyolojik tahlil biçimleri ve ekranları ile uyumlu olacak şekilde tasarlanmıştır, kullanılan malzemeye ideal floresans tarayıcılar ve ışık mikroskopları uygun bir mikroskop slayt. Bu biçim de birçok maddi-biyolojik etkileşimleri keşfetmek için uygun olduğu anlamına gelir. Ayrıca, biçim malzemeler yüzlerce paralel olarak taranması için izin verir. Bu, daha fazla sayıda malzeme her bir yeni kimyasal madde tek tek gösterildi bu sayede, geleneksel yöntemlerden daha taranması için olanak sağlar. Biyolojik-malzeme etkileşimleri için artan kapsamı izinBiyolojik yüzey etkileşimi, hem de belirli bir uygulama için uygun malzeme bulma mekanizmaları açıklama amaçlıdır.

<table border="1"><tbody><tr><td> Reaktif / ekipman Adı </td><td> Şirket </td><td> Katalog / Model numarası </td></tr><tr><td> Epoksi slaytlar </td><td> GENETIX </td><td> K2652 </td></tr><tr><td> Yazıcı İletişim </td><td> Biodot </td><td> XYZ3060 Platformu </td></tr><tr><td> Metal pin </td><td> ArrayIt </td><td> 946MP6B </td></tr><tr><td> TOF-SIMS enstrüman </td><td> ION-TOF </td><td></td></tr><tr><td> XPS enstrüman </td><td> Kratos </td><td></td></tr><tr><td> WCA aparatı </td><td> Krüss </td><td> DSA 100 </td></tr><tr><td> AFM </td><td> Bruker </td><td> Boyut Simge </td></tr><tr><td> RPMI-1640 hücre kültür besiyeri </td><td> Sigma-Aldrich </td><td> R0883 </td></tr><tr><td> SYTO17 </td><td> Invitrogen </td><td> S-7579 </td></tr></tbody></table>

polymer microarrays for high throughput discovery of biomaterials

Karışım, homojen bir karışım, iki veya daha fazla bileşenin bir araya getiren bir birim işlem olup. Bu eser bir in-line statik mikser kullanarak iki kıvamlı sıvı akışı karıştırma içerir. Mikser bileşenleri arasındaki arayüzey temas artırmak için kesilme ve yayılma akışı kullanan bir split-ve-rekombinasyona tasarımdır. Bir prototip split-ve-rekombinasyona (SAR) karıştırıcı plakaları bir PVC boru içinde yerinde yapılan ince lazer kesimli Poli (metil metakrilat) (PMMA) bir dizi hizalayarak tarafından yaptırılmıştır. Bu cihaz içinde karıştırma Şekil l&#39;deki fotoğrafta gösterilmiştir. 1. Kırmızı boya deney sıvısı bir kısmına ilave edildi ve büyük (boyanmamış) bileşeni içine karıştırılarak küçük bileşen olarak kullanılmıştır. Bu karıştırma bölümü içinden akması karıştırıcı girişinde, izleme sıvının enjekte tabaka iki tabaka ayrılmıştır. Sonraki her karıştırma bölümü üzerinde, yatay katmanlar sayısı çoğaltılır. Sonuç olarak, boya tek bir akış thr homojen dağılırcihazın kesit oughout. Ünitesinde karıştırılarak% 0.2 Carbopol ve benzeri kompozisyon katkılı tracer sıvı Newton olmayan bir test sıvısı, kullanma manyetik rezonans görüntüleme (MRG) ile görselleştirilir. MRG moleküler kimyasal ve fiziksel çevrenin yanı sıra mikron santimetre uzunluk ölçekleri ile ilgili örnek yapısı çok güçlü bir deneysel probu. Bu duyarlılık fiziksel, kimyasal ve / veya herhangi bir insana gözenekli ortam 1, 2 gıdalar arasında değişen malzemelerin biyolojik özelliklerini karakterize etmek için bu tekniklerin geniş uygulama sonuçlandı. Burada kullanılan ekipman ve şartlar bu tür yağlar da dahil olmak üzere normal su ve organik sıvılar gibi NMR mobil 1 H, önemli miktarlarda içeren görüntüleme sıvılar için uygundur. Geleneksel MRI endüstriyel ortamlar için uygundur ve bir laboratuvar (Şekil 2) içinde taşınabilir uğramamış süper iletken mıknatıslar kullanmıştır. Son gelişmeler in mıknatıs teknolojisi büyük hacimli inşaat görüntüleme işlemi akışları için uygun endüstriyel uyumlu mıknatıslar izin var. Burada, MRG karıştırma işlemi sırasında farklı eksen konumlarında mekansal çözüme bileşen konsantrasyonu sağlar. Bu çalışma belgeleri gerçek zamanlı kişisel bakım ürünleri için bir uygulama ile karıştırma ve dağıtım yoluyla yüksek viskoz akışkanların karıştırılması.

Watch this Scientific Journal Video about Polymer Microarrays for High Throughput Discovery of Biomaterials at JoVE.com

Polymer Microarrays for High Throughput Discovery of Biomaterials

Bir çip üzerinde fotopolimerizasyon tekniği kullanılarak bir polimer mikro oluşumu açıklaması. Atomik kuvvet mikroskobu, temas açısı ölçümleri, X-ışını fotoelektron spektroskopisi ve uçuş ikincil iyon kütle spektrometresi ve hücre bağlanma testinin zaman kullanarak yüksek aktarım yüzey karakterizasyonu da açıklanmıştır.

Biyomalzemelerin Yüksek Verimli Discovery için Polimer Mikroarray&#39;ler

The discovery of novel biomaterials that are optimized for a specific biological application is readily achieved using polymer microarrays, which allows a ...

polymer-microarrays-for-high-throughput-discovery-of-biomaterials

Universidad de Cartagena UDEC

Research

JoVE Journal

Bioengineering

14.4K Görüntüleme.  University of Nottingham. Bir çip üzerinde fotopolimerizasyon tekniği kullanılarak bir polimer mikro oluşumu açıklaması. Atomik kuvvet mikroskobu, temas açısı ölçümleri, X-ışını fotoelektron spektroskopisi ve uçuş ikincil iyon kütle spektrometresi ve hücre bağlanma testinin zaman kullanarak yüksek aktarım yüzey karakterizasyonu da açıklanmıştır.

Video: Polymer Microarrays for High Throughput Discovery of Biomaterials

Candida albicans Biofilm Chip (CaBChip) for High-throughput Antifungal Drug Screening

Candida albicans remains the main etiological agent of candidiasis, which currently represents the fourth most common nosocomial bloodstream infection in US hospitals1. These opportunistic infections pose a growing threat for an increasing number of compromised individuals, and carry unacceptably high mortality rates. This is in part due to the limited arsenal of antifungal drugs, but also to the emergence of resistance against the most commonly used antifungal agents. Further complicating treatment is the fact that a majority of manifestations of candidiasis are associated with the formation of biofilms, and cells within these biofilms show increased levels of resistance to most clinically-used antifungal agents2. Here we describe the development of a high-density microarray that consists of C. albicans nano-biofilms, which we have named CaBChip3. Briefly, a robotic microarrayer is used to print yeast cells of C. albicans onto a solid substrate. During printing, the yeast cells are enclosed in a three dimensional matrix using a volume as low as 50 nL and immobilized on a glass substrate with a suitable coating. After initial printing, the slides are incubated at 37 &deg;C for 24 hours to allow for biofilm development. During this period the spots grow into fully developed "nano-biofilms" that display typical structural and phenotypic characteristics associated with mature C. albicans biofilms (i.e. morphological complexity, three dimensional architecture and drug resistance)4. Overall, the CaBChip is composed of ~750 equivalent and spatially distinct biofilms; with the additional advantage that multiple chips can be printed and processed simultaneously. Cell viability is estimated by measuring the fluorescent intensity of FUN1 metabolic stain using a microarray scanner. This fungal chip is ideally suited for use in true high-throughput screening for antifungal drug discovery. Compared to current standards (i.e. the 96-well microtiter plate model of biofilm formation5), the main advantages of the fungal biofilm chip are automation, miniaturization, savings in amount and cost of reagents and analyses time, as well as the elimination of labor intensive steps. We believe that such chip will significantly speed up the antifungal drug discovery process.

Candida albicans Biofilm Chip CaBChip for High-throughput Antifungal Drug Screening

We have developed a high-density microarray platform consisting of 3D nano-biofilms of C. albicans called CaBChip. The susceptibility profile of drugs tested on a CaBChip is comparable to the conventional 96-well plate model, suggesting that the fungal chip is ideally suited for true high-throughput screening of antifungal drugs.

Yüksek verim Antifungal İlaç Tarama Candida albicans Biyofilm Chip (Ca BChip)

Candida  albicans remains the main etiological agent of candidiasis, which  currently represents the fourth most common nosocomial bloodstream infection ...

Biyomühendislik

Combinatorial Synthesis of and High-throughput Protein Release from Polymer Film and Nanoparticle Libraries

Polyanhydrides are a class of biomaterials with excellent biocompatibility and drug delivery capabilities. While they have been studied extensively with conventional one-sample-at-a-time synthesis techniques, a more recent high-throughput approach has been developed enabling the synthesis and testing of large libraries of polyanhydrides1. This will facilitate more efficient optimization and design process of these biomaterials for drug and vaccine delivery applications. The method in this work describes the combinatorial synthesis of biodegradable polyanhydride film and nanoparticle libraries and the high-throughput detection of protein release from these libraries. In this robotically operated method (Figure 1), linear actuators and syringe pumps are controlled by LabVIEW, which enables a hands-free automated protocol, eliminating user error. Furthermore, this method enables the rapid fabrication of micro-scale polymer libraries, reducing the batch size while resulting in the creation of multivariant polymer systems. This combinatorial approach to polymer synthesis facilitates the synthesis of up to 15 different polymers in an equivalent amount of time it would take to synthesize one polymer conventionally. In addition, the combinatorial polymer library can be fabricated into blank or protein-loaded geometries including films or nanoparticles upon dissolution of the polymer library in a solvent and precipitation into a non-solvent (for nanoparticles) or by vacuum drying (for films). Upon loading a fluorochrome-conjugated protein into the polymer libraries, protein release kinetics can be assessed at high-throughput using a fluorescence-based detection method (Figures 2 and 3) as described previously1. This combinatorial platform has been validated with conventional methods2 and the polyanhydride film and nanoparticle libraries have been characterized with 1H NMR and FTIR. The libraries have been screened for protein release kinetics, stability and antigenicity; in vitro cellular toxicity, cytokine production, surface marker expression, adhesion, proliferation and differentiation; and in vivo biodistribution and mucoadhesion1-11. The combinatorial method developed herein enables high-throughput polymer synthesis and fabrication of protein-loaded nanoparticle and film libraries, which can, in turn, be screened in vitro and in vivo for optimization of biomaterial performance.

This method describes the combinatorial synthesis of biodegradable polyanhydride film and nanoparticle libraries and the high-throughput detection of protein release from these libraries.

Kombinatorik Sentezi ve Polimer Film ve Nanoparçacık Kütüphaneler gelen Yüksek throughput Protein Yayın

Polyanhydrides are a class of biomaterials with excellent biocompatibility and drug delivery capabilities. While they have been studied extensively with ...

High-throughput Synthesis of Carbohydrates and Functionalization of Polyanhydride Nanoparticles

Transdisciplinary approaches involving areas such as material design, nanotechnology, chemistry, and immunology have to be utilized to rationally design efficacious vaccines carriers. Nanoparticle-based platforms can prolong the persistence of vaccine antigens, which could improve vaccine immunogenicity1. Several biodegradable polymers have been studied as vaccine delivery vehicles1; in particular, polyanhydride particles have demonstrated the ability to provide sustained release of stable protein antigens and to activate antigen presenting cells and modulate immune responses2-12.
The molecular design of these vaccine carriers needs to integrate the rational selection of polymer properties as well as the incorporation of appropriate targeting agents. High throughput automated fabrication of targeting ligands and functionalized particles is a powerful tool that will enhance the ability to study a wide range of properties and will lead to the design of reproducible vaccine delivery devices.
The addition of targeting ligands capable of being recognized by specific receptors on immune cells has been shown to modulate and tailor immune responses10,11,13 C-type lectin receptors (CLRs) are pattern recognition receptors (PRRs) that recognize carbohydrates present on the surface of pathogens. The stimulation of immune cells via CLRs allows for enhanced internalization of antigen and subsequent presentation for further T cell activation14,15. Therefore, carbohydrate molecules play an important role in the study of immune responses; however, the use of these biomolecules often suffers from the lack of availability of structurally well-defined and pure carbohydrates. An automation platform based on iterative solution-phase reactions can enable rapid and controlled synthesis of these synthetically challenging molecules using significantly lower building block quantities than traditional solid-phase methods16,17.
Herein we report a protocol for the automated solution-phase synthesis of oligosaccharides such as mannose-based targeting ligands with fluorous solid-phase extraction for intermediate purification. After development of automated methods to make the carbohydrate-based targeting agent, we describe methods for their attachment on the surface of polyanhydride nanoparticles employing an automated robotic set up operated by LabVIEW as previously described10. Surface functionalization with carbohydrates has shown efficacy in targeting CLRs10,11 and increasing the throughput of the fabrication method to unearth the complexities associated with a multi-parametric system will be of great value (Figure 1a).

In this article, a high throughput method is presented for the synthesis of oligosaccharides and their attachment to the surface of polyanhydride nanoparticles for further use in targeting specific receptors on antigen presenting cells.

Polianhidrid Nanopartiküller Yüksek throughput Karbonhidrat sentezi ve işlevsel

Transdisciplinary approaches involving areas such as material design, nanotechnology, chemistry, and immunology have to be utilized to rationally design ...

Evaluation of Biomaterials for Bladder Augmentation using Cystometric Analyses in Various Rodent Models

Renal function and continence of urine are critically dependent on the proper function of the urinary bladder, which stores urine at low pressure and expels it with a precisely orchestrated contraction. A number of congenital and acquired urological anomalies including posterior urethral valves, benign prostatic hyperplasia, and neurogenic bladder secondary to spina bifida/spinal cord injury can result in pathologic tissue remodeling leading to impaired compliance and reduced capacity1. Functional or anatomical obstruction of the urinary tract is frequently associated with these conditions, and can lead to urinary incontinence and kidney damage from increased storage and voiding pressures2. Surgical implantation of gastrointestinal segments to expand organ capacity and reduce intravesical pressures represents the primary surgical treatment option for these disorders when medical management fails3. However, this approach is hampered by the limitation of available donor tissue, and is associated with significant complications including chronic urinary tract infection, metabolic perturbation, urinary stone formation, and secondary malignancy4,5.
Current research in bladder tissue engineering is heavily focused on identifying biomaterial configurations which can support regeneration of tissues at defect sites. Conventional 3-D scaffolds derived from natural and synthetic polymers such as small intestinal submucosa and poly-glycolic acid have shown some short-term success in supporting urothelial and smooth muscle regeneration as well as facilitating increased organ storage capacity in both animal models and in the clinic6,7. However, deficiencies in scaffold mechanical integrity and biocompatibility often result in deleterious fibrosis8, graft contracture9, and calcification10, thus increasing the risk of implant failure and need for secondary surgical procedures. In addition, restoration of normal voiding characteristics utilizing standard biomaterial constructs for augmentation cystoplasty has yet to be achieved, and therefore research and development of novel matrices which can fulfill this role is needed.
In order to successfully develop and evaluate optimal biomaterials for clinical bladder augmentation, efficacy research must first be performed in standardized animal models using detailed surgical methods and functional outcome assessments. We have previously reported the use of a bladder augmentation model in mice to determine the potential of silk fibroin-based scaffolds to mediate tissue regeneration and functional voiding characteristics.11,12 Cystometric analyses of this model have shown that variations in structural and mechanical implant properties can influence the resulting urodynamic features of the tissue engineered bladders11,12. Positive correlations between the degree of matrix-mediated tissue regeneration determined histologically and functional compliance and capacity evaluated by cystometry were demonstrated in this model11,12. These results therefore suggest that functional evaluations of biomaterial configurations in rodent bladder augmentation systems may be a useful format for assessing scaffold properties and establishing in vivo feasibility prior to large animal studies and clinical deployment. In the current study, we will present various surgical stages of bladder augmentation in both mice and rats using silk scaffolds and demonstrate techniques for awake and anesthetized cystometry.

Surgical stages of bladder augmentation are described using 3-D scaffolds in murine and rat models. To test the efficacy of biomaterial configurations for use in bladder augmentation, techniques for both awake and anesthetized cystometry are presented.

Çeşitli Kemirgen Modeller sistometrik Analizleri kullanarak Mesane Büyütme için Biyomalzeme Değerlendirilmesi

Renal function and continence of urine are critically dependent on the proper function of the urinary bladder, which stores urine at low pressure and ...

A Full Skin Defect Model to Evaluate Vascularization of Biomaterials In Vivo

Insufficient vascularization is considered to be one of the main factors limiting the clinical success of tissue-engineered constructs. In order to evaluate new strategies that aim at improving vascularization, reliable methods are required to make the in-growth of new blood vessels into bio-artificial scaffolds visible and quantify the results. Over the past couple of years, our group has introduced a full skin defect model that enables the direct visualization of blood vessels by transillumination and provides the possibility of quantification through digital segmentation. In this model, one surgically creates full skin defects in the back of mice and replaces them with the material tested. Molecules or cells of interest can also be incorporated in such materials to study their potential effect. After an observation time of one&#8217;s own choice, materials are explanted for evaluation. Bilateral wounds provide the possibility of making internal comparisons that minimize artifacts among individuals as well as of decreasing the number of animals needed for the study. In comparison to other approaches, our method offers a simple, reliable and cost effective analysis. We have implemented this model as a routine tool to perform high-resolution screening when testing vascularization of different biomaterials and bio-activation approaches.

A Full Skin Defect Model to Evaluate Vascularization of Biomaterials In Vivo

Vascularization is key to approaches in successful tissue engineering. Therefore, reliable technologies are required to evaluate the development of vascular networks in tissue-constructs. Here we present a simple and cost-effective method to visualize and quantify vascularization in vivo.

A Tam Cilt Hata Modeli Biyomateryallerin vaskülarizasyonunu değerlendirin<em&gt; In Vivo</em

Insufficient vascularization is considered to be one of the main factors limiting the clinical success of tissue-engineered constructs. In order to ...

A Coupled Experiment-finite Element Modeling Methodology for Assessing High Strain Rate Mechanical Response of Soft Biomaterials

This study offers a combined experimental and finite element (FE) simulation approach for examining the mechanical behavior of soft biomaterials (e.g. brain, liver, tendon, fat, etc.) when exposed to high strain rates. This study utilized a Split-Hopkinson Pressure Bar (SHPB) to generate strain rates of 100-1,500 sec-1. The SHPB employed a striker bar consisting of a viscoelastic material (polycarbonate). A sample of the biomaterial was obtained shortly postmortem and prepared for SHPB testing. The specimen was interposed between the incident and transmitted bars, and the pneumatic components of the SHPB were activated to drive the striker bar toward the incident bar. The resulting impact generated a compressive stress wave (i.e. incident wave) that traveled through the incident bar. When the compressive stress wave reached the end of the incident bar, a portion continued forward through the sample and transmitted bar (i.e. transmitted wave) while another portion reversed through the incident bar as a tensile wave (i.e. reflected wave). These waves were measured using strain gages mounted on the incident and transmitted bars. The true stress-strain behavior of the sample was determined from equations based on wave propagation and dynamic force equilibrium. The experimental stress-strain response was three dimensional in nature because the specimen bulged. As such, the hydrostatic stress (first invariant) was used to generate the stress-strain response. In order to extract the uniaxial (one-dimensional) mechanical response of the tissue, an iterative coupled optimization was performed using experimental results and Finite Element Analysis (FEA), which contained an Internal State Variable (ISV) material model used for the tissue. The ISV material model used in the FE simulations of the experimental setup was iteratively calibrated (i.e. optimized) to the experimental data such that the experiment and FEA strain gage values and first invariant of stresses were in good agreement.

The current study prescribes a coupled experiment-finite element simulation methodology to obtain the uniaxial dynamic mechanical response of soft biomaterials (brain, liver, tendon, fat, etc.). The multiaxial experimental results that arose because of specimen bulging obtained from Split-Hopkinson Pressure Bar testing were rendered to a uniaxial true stress-strain behavior when simulated through iterative optimization of the finite element analysis of the biomaterial.

Yumuşak Biyomalzeme Yüksek Deformasyon Hızı Mekanik Tepki değerlendirilmesi için Coupled Deney-sonlu Eleman Modelleme Metodolojisi

This study offers a combined experimental and finite element (FE) simulation approach for examining the mechanical behavior of soft biomaterials (e.g. ...

Sandwich-like Microenvironments to Harness Cell/Material Interactions

Cell culture has been traditionally carried out on bi-dimensional (2D) substrates where cells adhere using ventral receptors to the biomaterial surface. However in vivo, most of the cells are completely surrounded by the extracellular matrix (ECM), resulting in a three-dimensional (3D) distribution of receptors. This may trigger differences in the outside-in signaling pathways and thus in cell behavior.
This article shows that stimulating the dorsal receptors of cells already adhered to a 2D substrate by overlaying a film of a new material (a sandwich-like culture) triggers important changes with respect to standard 2D cultures. Furthermore, the simultaneous excitation of ventral and dorsal receptors shifts cell behavior closer to that found in 3D environments. Additionally, due to the nature of the system, a sandwich-like culture is a versatile tool that allows the study of different parameters in cell/material interactions, e.g., topography, stiffness and different protein coatings at both the ventral and dorsal sides. Finally, since sandwich-like cultures are based on 2D substrates, several analysis procedures already developed for standard 2D cultures can be used normally, overcoming more complex procedures needed for 3D systems.

The following protocol describes the procedure to assemble sandwich-like cultures to be used as an intermediate stage between bi-dimensional (2D) and three-dimensional (3D) cellular environments. The engineered systems can have applications in microscopy, biomechanics, biochemistry and cell biology assays.

Sandviç gibi mikroçevrelerde Hücre / Malzeme Etkileşimleri Harness

Cell culture has been traditionally carried out on bi-dimensional (2D) substrates where cells adhere using ventral receptors to the biomaterial surface. ...

Using Tomoauto: A Protocol for High-throughput Automated Cryo-electron Tomography

Cryo-electron tomography (Cryo-ET) is a powerful three-dimensional (3-D) imaging technique for visualizing macromolecular complexes in their native context at a molecular level. The technique involves initially preserving the sample in its native state by rapidly freezing the specimen in vitreous ice, then collecting a series of micrographs from different angles at high magnification, and finally computationally reconstructing a 3-D density map. The frozen-hydrated specimen is extremely sensitive to the electron beam and so micrographs are collected at very low electron doses to limit the radiation damage. As a result, the raw cryo-tomogram has a very low signal to noise ratio characterized by an intrinsically noisy image. To better visualize subjects of interest, conventional imaging analysis and sub-tomogram averaging in which sub-tomograms of the subject are extracted from the initial tomogram and aligned and averaged are utilized to improve both contrast and resolution. Large datasets of tilt-series are essential to understanding and resolving the complexes at different states, conditions, or mutations as well as obtaining a large enough collection of sub-tomograms for averaging and classification. Collecting and processing this data can be a major obstacle preventing further analysis. Here we describe a high-throughput cryo-ET protocol based on a computer-controlled 300kV cryo-electron microscope, a direct detection device (DDD) camera and a highly effective, semi-automated image-processing pipeline software wrapper library tomoauto developed in-house. This protocol has been effectively utilized to visualize the intact type III secretion system (T3SS) in Shigella flexneri minicells. It can be applicable to any project suitable for cryo-ET.

We present a protocol on how to utilize high-throughput cryo-electron tomography to determine high resolution in situ structures of molecular machines. The protocol permits large amounts of data to be processed, avoids common bottlenecks and reduces resource downtime, allowing the user to focus on important biological questions.

Tomoauto kullanma: Bir Protokol Yüksek verim Otomatik Cryo-elektron Tomografi için

Cryo-electron tomography (Cryo-ET) is a powerful three-dimensional (3-D) imaging technique for visualizing macromolecular complexes in their native ...

A Microfluidic Platform for High-throughput Single-cell Isolation and Culture

Studying the heterogeneity of single cells is crucial for many biological questions, but is technically difficult. Thus, there is a need for a simple, yet high-throughput, method to perform single-cell culture experiments. Here, we report a microfluidic chip-based strategy for high-efficiency single-cell isolation (~77%) and demonstrate its capability of performing long-term single-cell culture (up to 7 d) and cellular heterogeneity analysis using clonogenic assay. These applications were demonstrated with KT98 mouse neural stem cells, and A549 and MDA-MB-435 human cancer cells. High single-cell isolation efficiency and long-term culture capability are achieved by using different sizes of microwells on the top and bottom of the microfluidic channel. The small microwell array is designed for precisely isolating single-cells, and the large microwell array is used for single-cell clonal culture in the microfluidic chip. This microfluidic platform constitutes an attractive approach for single-cell culture applications, due to its flexibility of adjustable cell culture spaces for different culture strategies, without decreasing isolation efficiency.

Here, we present a protocol for isolating and culturing single cells with a microfluidic platform, which utilizes a new microwell design concept to allow for high-efficiency single cell isolation and long-term clonal culture.

Yüksek verim Tek hücreli İzolasyonu ve Kültür mikroakışkan Platformu

Studying the heterogeneity of single cells is crucial for many biological questions, but is technically difficult. Thus, there is a need for a simple, yet ...

High-throughput Identification of Bacteria Repellent Polymers for Medical Devices

Medical devices are often associated with hospital-acquired infections, which place enormous strain on patients and the healthcare system as well as contributing to antimicrobial resistance. One possible avenue for the reduction of device-associated infections is the identification of bacteria-repellent polymer coatings for these devices, which would prevent bacterial binding at the initial attachment step. A method for the identification of such repellent polymers, based on the parallel screening of hundreds of polymers using a microarray, is described here. This high-throughput method resulted in the identification of a range of promising polymers that resisted binding of various clinically relevant bacterial species individually and also as multi-species communities. One polymer, PA13 (poly(methylmethacrylate-co-dimethylacrylamide)), demonstrated significant reduction in attachment of a number of hospital isolates when coated onto two commercially available central venous catheters. The method described could be applied to identify polymers for a wide range of applications in which modification of bacterial attachment is important.

A high-throughput microarray method for the identification of polymers which reduce bacterial surface binding on medical devices is described.

Tıbbi Cihazlar Bakterilerin yüksek verimlilik Kimlik Savar Polimerler

Medical devices are often associated with hospital-acquired infections, which place enormous strain on patients and the healthcare system as well as ...

Biyomalzemelerin Yüksek Verimli Discovery için Polimer Mikroarray'ler

Özet

Daha Fazla Video Keşfet

Bu videodaki bölümler