우리는 자금에 대한 미국 심장 협회 미드 - 애틀랜틱 제휴를 (0555407U, GLB) 감사드립니다.

<ol><li> 이전 electrospinning로 콜라겐은 육개월 소 진피에서 초산 기반의 프로세스를 사용하여 추출해야합니다. 이 추출된 콜라겐은 다음 dissolutions, precipitations 및 dialyses의 후속 시리즈를 통해 정화됩니다. 일단 콜라겐이 동결 건조된이며, electrospinning 과정을 시작할 수 있습니다. </li><li> polycaprolactone (PCL), 엘라스틴 (ELAS) 및 콜라겐 (콜) : 세 가지 자료 massed 있습니다. 이 자료는 별도로 용해됩니다 1,1​​,1,3,3,3 MG / ML, 각각 100 MG / ML, 200 MG / ML, 그리고 70 농도에 hexafluoro - 2 - 프로파놀 (HFP, TCI 미국). </li><li> 자료 98-2-0의 체적 비율에 다섯 가지의 섬광 튜브에 혼합 아르 PCL - ELAS - 콜 (intima), 45-45-10, 55-35-10 및 65-25-10 PCL - ELAS - 콜 (미디어), 그리고 70-0-30 PCL - ELAS - 콜 (adventitia). </li><li> 버스트, 봉합 보존 및 컴플 라 이언스 테스트를 위해 다층 혈관 이식은 3-1 구성에서 electrospun 동안 uni​​axial 인장 시험 및 개별 레이어 컴플 라 이언스 테스트를 위해 자료의 각 개별적으로 electrospun되었습니다. Uniaxial 인장 시험 공사장 공중 발판이 평평하고 직사각형했다 (2.5 cm x 세로 10.2 cm 두께 X 0.3 cm 길이) 개별 레이어와 다층 이식을 electrospin하는 데 사용되는 2mm 직경의 mandrels 이후 테스트 샘플을 펀칭 너무 작은되었습니다. </li><li> 모두 개인 및 다층 electrospinning 들어, 폴리머 솔루션은 18 게이지 야기한 팁 바늘로 비닐 3 ML 백톤 디킨슨 주사기에 로드된되었고, 세트 디스 펜 서리 속도 주사기 펌프에 위치. 다층 electrospinning 속도가 전환과 계층에 따라 다양한 동안 개인 electrospinning 요금, ML / HR 4로 설정되었습니다. 흐름 속도와 볼륨과 같은되었습니다 : intima 4 ML / 시간의 속도로 electrospun했고 0.5 ML의 볼륨 2 ML / 시간 각각 0.2 ML에 대한 내막과 중간 주사기를 모두 결합 변화가옵니다. 내막 주사기는 다음 차단되었으며 중간 계층은 ML / HR 2 ML / 시간 각 고분자 용액의 0.2 ML에 대한 언론과 adventitia 사이의 전이에 의해 다음 4 0.6 ML에 대한 회전을 허용했다. 마지막으로, 미디어가 중지되었으며 a​​dventitia 4 ML / 시간에서 0.4 ML에 대한 회전을 허용했다. </li><li> 모든 샘플은 이전에 모든 시험 1-18시간 50 MM EDC의 상호 연결되었습니다. </li><li> Uniaxial 인장 시험은 24 시간 동안 PBS에 수산화 한 electrospun 시트 6 샘플에서 수행되었다. &quot;개 - 뼈&quot;모양의 샘플 electrospun 매트에서 펀치와 100 N 부하 셀 및 10.0 mm / 분 확장 속도 MTS Bionix 200 테스트 시스템에서 테스트되었습니다. 피크 응력, 계수, 그리고 휴식의 변형은 TestWorks 버전 4를 사용하여 계산되었다. </li><li> 봉합사 보존 시험은 37 24 시간 동안 PBS에 담가 여섯 가지 electrospun의 이식 6 2mm 내경 관형 표본, ° C, MTS Bionix 200 테스트 시스템에서 50 N로드 셀 (MTS 시스템 주식 회사)와 함께에서 수행되었습니다 미국 국립 표준 연구소 2에서 설명한 절차에 걸쳐 직선에 따라 150.0 mm / 분의 확장 속도. 5-0 상용 PDS II 보라색 monofilament의 봉합은 샘플의 끝에서 2mm를 배치하고 봉합이 이식을 통해 뽑아했다 때까지 연장되었습니다. 피크 부하는 TestWorks 버전 4를 사용하여 g - 무력에 기록되었다. </li><li> 버스트 강도 테스트는 여섯 가지 electrospun의 이식 6 샘플에서 수행되었다. 버스트 튜브, 길이 2~3cm은 장치에 연결된, 그리고 2-0 실크 봉합사와 보안 1.5 mm 직경의 유두를 통해 장착되어, PBS에 수산화되었습니다. 공기 튜브가 2 버스트 때까지 5 mmHg / s의 속도로 압력을 증가, 시스템에 도입되었다. 결과는 튜브가 파열되는 mmHg의 압력으로보고됩니다. </li><li> 동적 준수는 가상의 생리 조건에서 3cm의 길이에서 여섯 가지 electrospun의 이식에서 가져온 여섯 2mm 내경 관형 이식에 대한 결정했습니다. 개별 레이어와 다층 구조 관형 모두 동일한 조건에서 electrospun 및 테스트되었습니다. 표본은 37 PBS로 가득 조직 성장 기술에 의해 개발된 기계 자극 (항목) 생물 반응기 ° C. 통해 지능형 조직 공학 테스트되었습니다 생물 반응기는 50분의 90 세 가지 압력 수준 80분의 120, 그리고 110분의 150 mmHg 수축기 / diastolic가 2 조사 있던 이식의 내부에 1Hz 순환 압력 변화, 3을 제공했습니다. </li></ol> 대표 결과 electrospinning 프로토콜이 올바르게 수행하는 경우, 최종 제품은 부드러운 원활한 튜브 레이어 사이의 박리없이 초기 징후와 함께해야합니다. uniaxial 인장 시험, 파열 강도 시험, 봉합 보존 테스트 및 컴플 라 이언스 테스트가 수행되는 경우, 결과는 중간 계층 강성이 증가로, 엘라스틴의 감소 금액과 관련된 기계적 성질이 stiffer 튜브를 입증해야한다는 의미합니다.

<ol>
	<li>McClure, M. J., Sell, S. A., Barnes, C. P., Bowen, W. C., Bowlin, G. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cross-linking+Electrospun+Polydioxanone-Soluble+Elastin+Blends:+Material+Characterization.">Cross-linking Electrospun Polydioxanone-Soluble Elastin Blends: Material Characterization.</a> Journal of Engineered Fibers and Fabrics. 3, 1-10 (2008).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Cardiovascular implants - Vascular graft protheses. VP20, (1994).</li><li>McClure, M. J., Sell, S. A., Simpson, D. G., Walpoth, B. H., Bowlin, G. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+three-layered+electrospun+matrix+to+mimic+native+arterial+architecture+using+polycaprolactone,+elastin,+and+collagen:+A+preliminary+study.">A three-layered electrospun matrix to mimic native arterial architecture using polycaprolactone, elastin, and collagen: A preliminary study.</a> Acta Biomater. , (2010).</li></ol>

몇몇 저자는 미국이 논문에서 제시에 관한 기술을 출원 국제 특허를 가지고 있고,이 기술은 Organogenesis 주식 허가되었습니다

본 연구의 가장 중요한 부분은 electrospinning 과정입니다. 3-1 입력 출력 노즐을 사용하는 경우, arching 및 충전 손실이 발생할 수 있습니다. 이 발생하면, 회전하는 폴리머와 관련된 전압 용접, &quot;젖은&quot;섬유가 발생하고 세 가지 레이어의 각 사이의 박리를 만들 줄어 듭니다. 따라서, 지속적인 전기 잠재력은 이상적인 다층 튜브를 얻기 위해 필수적입니다. 준수 불일치는 작?...

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<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">	
		
		<div>
		<table border="1">
		<thead>
		<tr>
		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
		</thead>
		<tbody>
		
<tr>
<td>Polycaprolactone</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Elastin</td>
<td>&nbsp;</td>
<td>Elastin Products Company</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Collagen</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Acetic Acid</td>
<td>&nbsp;</td>
<td>Fisher</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Sodium Chloride</td>
<td>&nbsp;</td>
<td>Fisher</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>TRIS</td>
<td>&nbsp;</td>
<td>Fisher</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>6 L Avanti J-HC Centrifuge</td>
<td>&nbsp;</td>
<td>Beckman Coulter</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>1,1,1,3,3,3 hexafluoro-2-propanol</td>
<td>&nbsp;</td>
<td>TCI America</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>3 ml Becton Dickinson Syringe</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>CZE1000R Rack Mount Power Supply</td>
<td>&nbsp;</td>
<td>Spellman</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>High-Pressure Syringe Pump</td>
<td>&nbsp;</td>
<td>Cole Parmer</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide</td>
<td>&nbsp;</td>
<td>Pierce</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>70 % ethanol</td>
<td>&nbsp;</td>
<td>Sigma Aldrich</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>ImageTool 3.0 software</td>
<td>&nbsp;</td>
<td>Shareware provided by UTHSCSA</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Scanning Electron Microscope</td>
<td>&nbsp;</td>
<td>Zeiss EV050</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>MTS Bionix 200 testing system</td>
<td>&nbsp;</td>
<td>MTS Systems Corp.</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>TestWorks version 4</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Intelligent Tissue Engineering via Mechanical Stimulation (ITEMS) Bioreactor</td>
<td>&nbsp;</td>
<td>Tissue Growth Technologies</td>
<td>&nbsp;</td>
<td>&nbsp;</td>		</tbody>
		</table>
		</div>

tri-layered electrospinning to mimic native arterial architecture using polycaprolactone, elastin, and collagen: a preliminary study

기본 동맥 통해 콜라겐과 엘라스틴은 기계 백본을 제공하는 선박의 파열을 방지하고, 타악기 deformations에 따라 복구를 추진, 중요한 역할을한다. 본 연구의 목표는 엘라스틴의 추가와 45-45-10의 결합, 55-35로 콜라겐과 폴리 (caprolactone) (PCL)으로 구성된 다층 electrospun 도관을 fabricating하여 기본 동맥의 구조를 모방하는 것이었다 - 조직 재생에 도움이되는 유지하면서 10, 65-25-10는 PCL - ELAS - 콜, 기본 동맥 조직을 나타내는 기계적 성질을 설명합니다. 전체 이식 및 개별 레이어는 uniaxial 인장 시험, 동적 준수, 봉합 보존 및 버스트 강도를 사용하여 분석했다. 11.8 MPA - uniaxial 결과는 2.0의 평균 계수 범위를 시연하는 동안 2.8 % / 100 mmHg, - 준수 결과는 중간 / 중간 계층에 대한 변경 사항이 0.8에 이르기까지 전체 그래프트 준수 값 전체 그래프트 동작을 변경하는 것으로 나타났습니다. 계수 및 규정 준수 데이터를 모두 원래 동맥의 범위 내에서 값을 표시합니다. 수학 모델링은 레이어 강성의 변화는 전체 원주 벽 스트레스에 미치는 영향 및 디자인 지원은 재료의 최고의 기계적 조합을 달성할 수있을만큼 보여주 구현되었습니다. 전반적으로, 결과는 그래프트는 레이어 속성을 변경하여 트라이 - 계층 구조를 모방하기위한 수 지적했다.

Watch this Scientific Journal Video about Tri-layered Electrospinning to Mimic Native Arterial Architecture using Polycaprolactone, Elastin, and Collagen: A Preliminary Study at JoVE.com

Tri-layered Electrospinning to Mimic Native Arterial Architecture using Polycaprolactone, Elastin, and Collagen: A Preliminary Study

본 연구의 목적은 동맥 벽 원래 세 계층 아키텍처를 모방하는 것이었다. 이것을 달성하기 위해, electrospinning은 3-1 (입출력) 노즐의 사용과 고용 및 polycaprolactone, 엘라스틴, 콜라겐의 결합되었다.

Polycaprolactone, 엘라스틴, 콜라겐을 사용하여 네이티브 아티 건축을 모방하기 위해 트라이 - 계층 Electrospinning : 예비 연구

Throughout native artery, collagen and elastin play an important role, providing a mechanical backbone, preventing vessel rupture, and promoting recovery ...

tri-layered-electrospinning-to-mimic-native-arterial-architecture

Research

JoVE Journal

Bioengineering

12.8K 조회수.  Virginia Commonwealth University. 본 연구의 목적은 동맥 벽 원래 세 계층 아키텍처를 모방하는 것이었다. 이것을 달성하기 위해, electrospinning은 3-1 (입출력) 노즐의 사용과 고용 및 polycaprolactone, 엘라스틴, 콜라겐의 결합되었다.

비디오: Tri-layered Electrospinning to Mimic Native Arterial Architecture using Polycaprolactone, Elastin, and Collagen: A Preliminary Study

Design of a Cyclic Pressure Bioreactor for the Ex Vivo Study of Aortic Heart Valves

The aortic valve, located between the left ventricle and the aorta, allows for unidirectional blood flow, preventing backflow into the ventricle. Aortic valve leaflets are composed of interstitial cells suspended within an extracellular matrix (ECM) and are lined with an endothelial cell monolayer. The valve withstands a harsh, dynamic environment and is constantly exposed to shear, flexion, tension, and compression. Research has shown calcific lesions in diseased valves occur in areas of high mechanical stress as a result of endothelial disruption or interstitial matrix damage1-3. Hence, it is not surprising that epidemiological studies have shown high blood pressure to be a leading risk factor in the onset of aortic valve disease4. 
The only treatment option currently available for valve disease is surgical replacement of the diseased valve with a bioprosthetic or mechanical valve5. Improved understanding of valve biology in response to physical stresses would help elucidate the mechanisms of valve pathogenesis. In turn, this could help in the development of non-invasive therapies such as pharmaceutical intervention or prevention. Several bioreactors have been previously developed to study the mechanobiology of native or engineered heart valves6-9. Pulsatile bioreactors have also been developed to study a range of tissues including cartilage10, bone11 and bladder12. The aim of this work was to develop a cyclic pressure system that could be used to elucidate the biological response of aortic valve leaflets to increased pressure loads. 
The system consisted of an acrylic chamber in which to place samples and produce cyclic pressure, viton diaphragm solenoid valves to control the timing of the pressure cycle, and a computer to control electrical devices. The pressure was monitored using a pressure transducer, and the signal was conditioned using a load cell conditioner. A LabVIEW program regulated the pressure using an analog device to pump compressed air into the system at the appropriate rate. The system mimicked the dynamic transvalvular pressure levels associated with the aortic valve; a saw tooth wave produced a gradual increase in pressure, typical of the transvalvular pressure gradient that is present across the valve during diastole, followed by a sharp pressure drop depicting valve opening in systole. The LabVIEW program allowed users to control the magnitude and frequency of cyclic pressure. The system was able to subject tissue samples to physiological and pathological pressure conditions. This device can be used to increase our understanding of how heart valves respond to changes in the local mechanical environment.

Design of a Cyclic Pressure Bioreactor for the Ex Vivo Study of Aortic Heart Valves

A cyclic pressure bioreactor capable of subjecting heart valve tissue to physiological and pathological pressure conditions has been designed. A LabVIEW program allows users to control pressure magnitude, amplitude and frequency. This device can be used to study the mechanobiology of heart valve tissue or isolated cells.

의 순환 압력 생물 반응기 설계 예 VIVO</em대동맥 심장 밸브> 학습

The aortic valve, located between the left ventricle and the aorta, allows for unidirectional blood flow, preventing backflow into the ventricle. Aortic ...

연구

생체공학

In vitro Synthesis of Native, Fibrous Long Spacing and Segmental Long Spacing Collagen

Collagen fibrils are present in the extracellular matrix of animal tissue to provide structural scaffolding and mechanical strength. These native collagen fibrils have a characteristic banding periodicity of ~67 nm and are formed in vivo through the hierarchical assembly of Type I collagen monomers, which are 300 nm in length and 1.4 nm in diameter. In vitro, by varying the conditions to which the monomer building blocks are exposed, unique structures ranging in length scales up to 50 microns can be constructed, including not only native type fibrils, but also fibrous long spacing and segmental long spacing collagen. Herein, we present procedures for forming the three different collagen structures from a common commercially available collagen monomer. Using the protocols that we and others have published in the past to make these three types typically lead to mixtures of structures. In particular, unbanded fibrils were commonly found when making native collagen, and native fibrils were often present when making fibrous long spacing collagen. These new procedures have the advantage of producing the desired collagen fibril type almost exclusively. The formation of the desired structures is verified by imaging using an atomic force microscope.

In vitro Synthesis of Native, Fibrous Long Spacing and Segmental Long Spacing Collagen

Simple and reproducible procedures are described for making three structurally distinct collagen assemblies from a common commercially available Type I collagen monomer. Native type, fibrous long spacing or segmental long spacing collagen can be constructed by varying the conditions to which the 300 nm long and 1.4 nm diameter monomer building block is exposed.

기본, 섬유 긴 간격 및 Segmental 긴 간격 콜라겐의 체외 합성에

Collagen fibrils are present in the  extracellular matrix of animal tissue to provide structural scaffolding and  mechanical strength. These native ...

An Improved Method for the Preparation of Type I Collagen From Skin

Soluble type 1 collagen (COL1) is used extensively as an adhesive substrate for cell cultures and as a cellular scaffold for regenerative applications. Clinically, this protein is widely used for cosmetic surgery, dermal injections, bone grafting, and reconstructive surgery. The sources of COL1 for these procedures are commonly nonhuman, which increases the potential for inflammation and rejection as well as xenobiotic disease transmission. In view of this, a method to efficiently and quickly purify COL1 from limited quantities of autologously-derived tissues would circumvent many of these issues; however, standard isolation protocols are lengthy and often require large quantities of collagenous tissues. Here, we demonstrate an efficient COL1 extraction method that reduces the time needed to isolate and purify this protein from about 10 days to less than 3 hr. We chose the dermis as our tissue source because of its availability during many surgical procedures. This method uses traditional extraction buffers combined with forceful agitation and centrifugal filtration to obtain highly-pure, soluble COL1 from small amounts of corium. Briefly, dermal biopsies are washed thoroughly in ice-cold dH2O after removing fat, connective tissue, and hair. The skin samples are stripped of noncollagenous proteins and polysaccharides using 0.5 M sodium acetate and a high speed bench-top homogenizer. Collagen from residual solids is subsequently extracted with a 0.075 M sodium citrate buffer using the homogenizer. These extracts are purified using 100,000 MW cut-off centrifugal filters that yield COL1 preparations of comparable or superior quality to commercial products or those obtained using traditional procedures. We anticipate this method will facilitate the utilization of autologously-derived COL1 for a multitude of research and clinical applications.

Traditional procedures for the isolation of soluble type 1 collagen (COL1) require about 10 days from start to finish because of lengthy buffer incubations and laborious resuspensions of fibrils. Here, we describe a means to purify COL1 from small dermal biopsies in less than 3 hr.

피부에서 타입 I 콜라겐의 제조를위한 개선 된 방법

Soluble type 1 collagen (COL1) is used extensively as an adhesive substrate for cell cultures and as a cellular scaffold for regenerative applications. ...

Imaging Denatured Collagen Strands In vivo and Ex vivo via Photo-triggered Hybridization of Caged Collagen Mimetic Peptides

Collagen is a major structural component of the extracellular matrix that supports tissue formation and maintenance. Although collagen remodeling is an integral part of normal tissue renewal, excessive amount of remodeling activity is involved in tumors, arthritis, and many other pathological conditions. During collagen remodeling, the triple helical structure of collagen molecules is disrupted by proteases in the extracellular environment. In addition, collagens present in many histological tissue samples are partially denatured by the fixation and preservation processes. Therefore, these denatured collagen strands can serve as effective targets for biological imaging. We previously developed a caged collagen mimetic peptide (CMP) that can be photo-triggered to hybridize with denatured collagen strands by forming triple helical structure, which is unique to collagens. The overall goals of this procedure are i)&#160;to image denatured collagen strands resulting from normal remodeling activities in vivo, and ii) to visualize collagens in ex vivo tissue sections using the photo-triggered caged CMPs. To achieve effective hybridization and successful in vivo and ex vivo imaging, fluorescently labeled caged CMPs are either photo-activated immediately before intravenous injection, or are directly activated on tissue sections. Normal skeletal collagen remolding in nude mice and collagens in prefixed mouse cornea tissue sections are imaged in this procedure. The imaging method based on the CMP-collagen hybridization technology presented here could lead to deeper understanding of the tissue remodeling process, as well as allow development of new diagnostics for diseases associated with high collagen remodeling activity.

Imaging Denatured Collagen Strands In vivo and Ex vivo via Photo-triggered Hybridization of Caged Collagen Mimetic Peptides

This procedure demonstrates in vivo near IR fluorescence imaging of collagen remodeling activities in mice as well as ex vivo staining of collagens in tissue sections using caged collagen mimetic peptides that can be photo-triggered to hybridize with denatured collagen strands.

변성 콜라겐 물가 이미징<em&gt; 생체 내</em&gt;와<em&gt; 예 생체 내</em&gt; 리테이너 타입 콜라겐 미메시스 펩티드의 사진 트리거 하이브리드를 통해

Collagen is a major structural component of the extracellular matrix that supports tissue formation and maintenance. Although collagen remodeling is an ...

Combination of Microstereolithography and Electrospinning to Produce Membranes Equipped with Niches for Corneal Regeneration

Corneal problems affect millions of people worldwide reducing their quality of life significantly. Corneal disease can be caused by illnesses such as Aniridia or Steven Johnson Syndrome as well as by external factors such as chemical burns or radiation. Current treatments are (i) the use of corneal grafts and (ii) the use of stem cell expanded in the laboratory and delivered on carriers (e.g., amniotic membrane); these treatments are relatively successful but unfortunately they can fail after 3-5 years. There is a need to design and manufacture new corneal biomaterial devices able to mimic in detail the physiological environment where stem cells reside in the cornea. Limbal stem cells are located in the limbus (circular area between cornea and sclera) in specific niches known as the Palisades of Vogt. In this work we have developed a new platform technology which combines two cutting-edge manufacturing techniques (microstereolithography and electrospinning) for the fabrication of corneal membranes that mimic to a certain extent the limbus. Our membranes contain artificial micropockets which aim to provide cells with protection as the Palisades of Vogt do in the eye.

We report a technique for the fabrication of micropockets within electrospun membranes in which to study cell behavior. Specifically, we describe a combination of microstereolithography and electrospinning for the production of PLGA (Poly(lactide-co-glycolide)) corneal biomaterial devices equipped with microfeatures.

마이크로 광 및 전기 방사의 조합은 각막 재생을위한 틈새를 장착 멤브레인을 생산하는

Corneal problems affect millions of people worldwide reducing their quality of life significantly. Corneal disease can be caused by illnesses such as ...

Planar Gradient Diffusion System to Investigate Chemotaxis in a 3D Collagen Matrix

The importance of cell migration can be seen through the development of human life. When cells migrate, they generate forces and transfer these forces to their surrounding area, leading to cell movement and migration. In order to understand the mechanisms that can alter and/or affect cell migration, one can study these forces. In theory, understanding the fundamental mechanisms and forces underlying cell migration holds the promise of effective approaches for treating diseases and promoting cellular transplantation. Unfortunately, modern chemotaxis chambers that have been developed are usually restricted to two dimensions (2D) and have complex diffusion gradients that make the experiment difficult to interpret. To this end, we have developed, and describe in this paper, a direct-viewing chamber for chemotaxis studies, which allows one to overcome modern chemotaxis chamber obstacles able to measure cell forces and specific concentration within the chamber in a 3D environment to study cell 3D migration. More compelling, this approach allows one to successfully model diffusion through 3D collagen matrices and calculate the coefficient of diffusion of a chemoattractant through multiple different concentrations of collagen, while keeping the system simple and user friendly for traction force microscopy (TFM) and digital volume correlation (DVC) analysis.

Cell migration is an important part of human development and life. In order to understand the mechanisms that can alter cell migration, we present a planar gradient diffusion system to investigate chemotaxis in a 3D collagen matrix, which allows one to overcome modern diffusion chamber limitations of existing assays.

평면 그라데이션 확산 시스템은 3D 콜라겐 매트릭스에 화성을 조사하기 위해

The importance of cell migration can be seen through the development of human life. When cells migrate, they generate forces and transfer these forces to ...

Adapting the Electrospinning Process to Provide Three Unique Environments for a Tri-layered In Vitro Model of the Airway Wall

Electrospinning is a highly adaptable method producing porous 3D fibrous scaffolds that can be exploited in in vitro cell culture. Alterations to intrinsic parameters within the process allow a high degree of control over scaffold characteristics including fiber diameter, alignment and porosity. By developing scaffolds with similar dimensions and topographies to organ- or tissue-specific extracellular matrices (ECM), micro-environments representative to those that cells are exposed to in situ can be created. 
The airway bronchiole wall, comprised of three main micro-environments, was selected as a model tissue. Using decellularized airway ECM as a guide, we electrospun the non-degradable polymer, polyethylene terephthalate (PET), by three different protocols to produce three individual electrospun scaffolds optimized for epithelial, fibroblast or smooth muscle cell-culture. Using a commercially available bioreactor system, we stably co-cultured the three cell-types to provide an in vitro model of the airway wall over an extended time period.
This model highlights the potential for such methods being employed in in vitro diagnostic studies investigating important inter-cellular cross-talk mechanisms or assessing novel pharmaceutical targets, by providing a relevant platform to allow the culture of fully differentiated adult cells within 3D, tissue-specific environments.

Adapting the Electrospinning Process to Provide Three Unique Environments for a Tri-layered In Vitro Model of the Airway Wall

Advancements in biomaterial technologies enable the development of three-dimensional multi-cell-type constructs. We have developed electrospinning protocols to produce three individual scaffolds to culture the main structural cells of the airway to provide a 3D in vitro model of the airway bronchiole wall.

전기 방사를 적응하는 것은 트라이 계층에 대한 세 가지 독특한 환경을 제공하기 위해<em&gt; 체외</em&gt;기도 벽의 모델

Electrospinning is a highly adaptable method producing porous 3D fibrous scaffolds that can be exploited in in vitro cell culture. Alterations to ...

Preparation of 3D Collagen Gels and Microchannels for the Study of 3D Interactions In Vivo

Historically, most cellular processes have been studied in only 2 dimensions. While these studies have been informative about general cell signaling mechanisms, they neglect important cellular cues received from the structural and mechanical properties of the local microenvironment and extracellular matrix (ECM). To understand how cells interact within a physiological ECM, it is important to study them in the context of 3 dimensional assays. Cell migration, cell differentiation, and cell proliferation are only a few processes that have been shown to be impacted by local changes in the mechanical properties of a 3-dimensional ECM. Collagen I, a core fibrillar component of the ECM, is more than a simple structural element of a tissue. Under normal conditions, mechanical cues from the collagen network direct morphogenesis and maintain cellular structures. In diseased microenvironments, such as the tumor microenvironment, the collagen network is often dramatically remodeled, demonstrating altered composition, enhanced deposition and altered fiber organization. In breast cancer, the degree of fiber alignment is important, as an increase in aligned fibers perpendicular to the tumor boundary has been correlated to poorer patient prognosis1. Aligned collagen matrices result in increased dissemination of tumor cells via persistent migration2,3. The following is a simple protocol for embedding cells within a 3-dimensional, fibrillar collagen hydrogel. This protocol is readily adaptable to many platforms, and can reproducibly generate both aligned and random collagen matrices for investigation of cell migration, cell division, and other cellular processes in a tunable, 3-dimensional, physiological microenvironment.

Preparation of 3D Collagen Gels and Microchannels for the Study of 3D Interactions In Vivo

Collagen is a core component of the ECM, and provides essential cues for several cellular processes ranging from migration to differentiation and proliferation. Provided here is a protocol for embedding cells within 3D collagen hydrogels, and a more advanced technique for generating randomized or aligned collagen matrices using PDMS microchannels.

3D 상호 작용의 연구에 대한 3D 콜라겐 젤과 마이크로 채널 준비<em&gt; 생체</em

Historically, most cellular processes have been studied in only 2 dimensions.  While these studies have been informative about general cell signaling ...

Melt Electrospinning Writing of Three-dimensional Poly(&#949;-caprolactone) Scaffolds with Controllable Morphologies for Tissue Engineering Applications

This tutorial reflects on the fundamental principles and guidelines for electrospinning writing with polymer melts, an additive manufacturing technology with great potential for biomedical applications. The technique facilitates the direct deposition of biocompatible polymer fibers to fabricate well-ordered scaffolds in the sub-micron to micro scale range. The establishment of a stable, viscoelastic, polymer jet between a spinneret and a collector is achieved using an applied voltage and can be direct-written. A significant benefit of a typical porous scaffold is a high surface-to-volume ratio which provides increased effective adhesion sites for cell attachment and growth. Controlling the printing process by fine-tuning the system parameters enables high reproducibility in the quality of the printed scaffolds. It also provides a flexible manufacturing platform for users to tailor the morphological structures of the scaffolds to their specific requirements. For this purpose, we present a protocol to obtain different fiber diameters using melt electrospinning writing (MEW) with a guided amendment of the parameters, including flow rate, voltage and collection speed. Furthermore, we demonstrate how to optimize the jet, discuss often experienced technical challenges, explain troubleshooting techniques and showcase a wide range of printable scaffold architectures.

Melt Electrospinning Writing of Three-dimensional Poly(&amp;#949;-caprolactone) Scaffolds with Controllable Morphologies for Tissue Engineering Applications

This protocol serves as a comprehensive guideline to fabricate scaffolds via electrospinning with polymer melts in a direct writing mode. We systematically outline the process and define the appropriate parameter settings for achieving targeted scaffold architectures.

조직 공학 응용 프로그램에 대 한 제어 형태학과 3 차원 Poly(ε-caprolactone) 장비의 전기 글 녹아

This tutorial reflects on the fundamental principles and guidelines for electrospinning writing with polymer melts, an additive manufacturing technology ...

Creating a Structurally Realistic Finite Element Geometric Model of a Cardiomyocyte to Study the Role of Cellular Architecture in Cardiomyocyte Systems Biology

With the advent of three-dimensional (3D) imaging technologies such as electron tomography, serial-block-face scanning electron microscopy and confocal microscopy, the scientific community has unprecedented access to large datasets at sub-micrometer resolution that characterize the architectural remodeling that accompanies changes in cardiomyocyte function in health and disease. However, these datasets have been under-utilized for&#160;investigating the role of cellular architecture remodeling in cardiomyocyte function. The purpose of this protocol is to outline how to create an accurate finite element model of a cardiomyocyte using high resolution electron microscopy and confocal microscopy images. A detailed and accurate model of cellular architecture has significant potential to provide new insights into cardiomyocyte biology, more than experiments alone can garner. The power of this method lies in its ability to computationally fuse information from two disparate imaging modalities of cardiomyocyte ultrastructure to develop one unified and detailed model of the cardiomyocyte. This protocol outlines steps to integrate electron tomography and confocal microscopy images of adult male Wistar (name for a specific breed of albino rat) rat cardiomyocytes to develop a half-sarcomere finite element model of the cardiomyocyte. The procedure generates a 3D finite element model that contains an accurate, high-resolution depiction (on the order of ~35 nm) of the distribution of mitochondria, myofibrils and ryanodine receptor clusters that release the necessary calcium for cardiomyocyte contraction from the sarcoplasmic reticular network (SR) into the myofibril and cytosolic compartment. The model generated here as an illustration does not incorporate details of the transverse-tubule architecture or the sarcoplasmic reticular network and is therefore a minimal model of the cardiomyocyte. Nevertheless, the model can already be applied in simulation-based investigations into the role of cell structure in calcium signaling and mitochondrial bioenergetics, which is illustrated and discussed using two case studies that are presented following the detailed protocol.

This protocol outlines a novel method to create a spatially detailed finite element model of the intracellular architecture of cardiomyocytes from electron microscopy and confocal microscopy images. The power of this spatially detailed model is demonstrated using case studies in calcium signaling and bioenergetics.

Cardiomyocyte 시스템 생물학에서 세포 아키텍처의 역할을 연구 하기 Cardiomyocyte의 구조적으로 현실적인 유한 요소 형상 모델 생성

With the advent of three-dimensional (3D) imaging technologies such as electron tomography, serial-block-face scanning electron microscopy and confocal ...