저자는 원고를 준비하여 시스템 및 지원 Valtresa의 마일즈의 설계 및 제조와 그들의 도움을 쉐그 Schipke, 다니엘 체서에게 감사하고 있습니다.

1. 조직 하베스트 및 준비 <ol><li> 대동맥 밸브는 바로 죽은 후 더 이상 120 이상 파운드 무게 성인 돼지에서 수집해야합니다. </li><li> 멸균 인산과 함께 두 번 밸브를 세척 식염수 (PBS)와 얼음에 실험실로 전송이 버퍼. </li><li> 모든 후속 단계는 무균 조건 하에서 수행되어야합니다. </li><li> 그 전단지가 찢어이나 석회화, 변성의 기호를 표시하지 않도록. 환대에서 거리의 1 / 3 절단하여 대동맥 루트에서 전단지를 제거합니다. </li><li> 플레이스 여섯 잘 접시의 각각의 우물에서 전단지 37 ° C와 5 % CO 2에서 1퍼센트 anti-biotic/anti-mycotic 솔루션와 10 % 태아 소 혈청과 보충 3ml Dulbecco의 수정된 이글 매체와 함께 밤새 품어. </li><li> 대체 절연 세포 6 - 잘 문화 접시에 씨앗을 품고 및 압력 장치에 사용될 수 있듯이. 이전 13 14 설명된대로 밸브 내피 세포와 중간 세포의 분리는 수행할 수 있습니다. </li></ol> 2. 압력 연구 <ol><li> 맞춤 만든 압력 시스템은 대동맥 밸브 조직 15 순환 압력 mechanobiological 효과를 연구하기 위해 설계되었습니다. </li><li> 컴퓨터에 로그인하고 labVIEW 프로그램 (그림 1)을 엽니다. </li><li> 보정 : <ol><li> 이전 실험하기 위해 시스템이 적절히 보정해야합니다. </li><li> 회로 기판에 전원 공급 장치를 연결합니다. 이것은 챔버로 밖의 공기의 흐름을 제어 솔레노이드 밸브에 전원을 제공합니다. </li><li> 압축 공기가 시스템에 연결되어 있는지 확인하고 전체 속도로 공기 공급 장치를 엽니다. </li><li> 신호 증폭기를 켭니다. 전압 독서가 0.00 있는지 확인하십시오. 필요에 따라 조정 </li><li> labVIEW 인터페이스는 &quot;TEST / 기록&quot;라고 표시된 스위치가 있습니다. 스위치가 &quot;TEST&quot;로 설정되어 있는지 확인하십시오. &quot;공기 공급&quot;유입 솔레노이드 밸브를 열고 표시된 버튼을 클릭합니다. </li><li> 가스 압력 조절기를 사용하여, 1 PSI에 압축 공기 챔버의 기압. 챔버의 압력 챔버의 최종 플레이트 후면에있는 디지털 압력 게이지를 사용하여 읽을 수 있습니다. 압력 equilibrated되면, 신호 증폭기에서 전압 독서를 기록합니다. 2, 3, 4 및 5 PSI에 대해 반복합니다. </li><li> 압력 대 전압의 보정 곡선을 구축. 압력은 PSI에서 mmHg로 변환해야합니다. 그래프의 방정식은 labVIEW 프로그램의 코드에 삽입할 수 있습니다 </li></ol></li><li> 압력 챔버에서 알루미늄 전면 플레이트를 제거하고 70 % 에탄올로 챔버를 스프레이. 잔여 에탄올 가스가 분산 수 있도록 10 분 최소 둡니다. </li><li> 챔버에 전단지 샘플을 포함하고있는 여섯 잘 플레이트를 삽입하고 프런트 엔드 플레이트를 교체하십시오. 봉인 손으로 네 개의 스레드 막대 (경판의 각 모서리에 위치)에있는 너트를 강화하여 밀폐 있는지 확인하십시오. 37 ° C 배양기에서 압력 챔버를 놓습니다. 압력 챔버의 구조 다이어그램은 그림 2에 표시됩니다. </li><li> 인터페이스는 압축 공기 입력 및 출력 사이의 시스템의 순환 시간을 제공하기 위해 사용자에게 프롬프트합니다. 이러한 1Hz의 주파수에서 각각 0.6s와 모방에 0.4s diastolic과 수축기 조건에 설정해야합니다. 사용자는 또한 데이터 파일의 경로를 입력합니다. </li><li> labVIEW, 실행을 클릭하고 &quot;레코드&quot;로 &quot;TEST / 레코드가&quot;토글 스위치. </li><li> 압력이 labVIEW 인터페이스에 대한 그래프를 사용하여 원하는 수준에 있는지 확인하십시오. 압력은 가스 압력 조절기를 사용하여 조정할 수 있습니다. </li><li> 시간의 원하는 기간 동안 프로그램을 실행합니다. </li><li> 실험이 완료되면, labVIEW에있는 중지 버튼을 클릭 공기 공급 장치를 끄고 압력 챔버에 배기 밸브를 엽니다. </li><li> 챔버에서 프런트 엔드 플레이트를 제거하고 여섯 잘 플레이트가 포함된 샘플을 검색할 수 있습니다. 샘플은 현재 유전자 발현, 단백질 표현, 조직학, 기계적 성질 등의 분석 수 </li></ol> 3. 대표 결과 : 압력 시스템은 normotensive 하에서 관찰 최대 transvalvular 압력을 시뮬레이션 할 수있어, 내가 무대 II 신경성 조건을 무대. 단, 압력은 생체내에 본질적으로 제로입니다 수축기 압력 기울기를 모방 수 없습니다. 주파수는 0.6s 0.4s의과 배기 시간의 공기 유입 시간, 1Hz에서 관리하고 있습니다. 시스템에서 얻은 정상 및 높은 압력 조건의 대표 압력 파형은 그림 3에서 볼 수 있습니다. <img src="/files/ftp_upload/3316/3316fig1.jpg" alt="그림 1"/> 그림 1 : LabVIEW 인터페이스의 스크린 샷. <img src="/files/ftp_upload/3316/3316fig2.jpg" alt="그림 2"/> 그림 2 : 압력 챔버의 압력 챔버 A. 사시의 도식 그림, 압력 챔버의 B. 사이드보기;압력 챔버의 C. 톱 볼 수 있습니다. <img src="/files/ftp_upload/3316/3316fig3.jpg" alt="그림 3"/> 그림 3 : (A) normotensive, (B) 나는 신경성 스테이지, 그리고 (C) 스테이지 II 신경성 조건에서 압력 챔버 내의 압력 시뮬레이션의 그래프.

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관심 없음 충돌 선언하지 않습니다.

압력 시스템은 성공적으로 diastolic transvalvular 압력을 대표했다 순환 압력에 대동맥 밸브 전단지를 노출. 압력은 40 mmHg로 감소 그러나, 그것은 수축기 transvalvular 압력을 모방 수 없습니다. Transvalvular 압력은 오름차순 대동맥의 압력과 좌심실 사이의 차이입니다. 심장 확장하는 동안, 밸브가 닫힐 때, 압력 차이가 normotensive 조건 90 mmHg 이하 80mmHg이며 무대 II의 고혈압은 각각 단계 100mmHg. 수축기 동안, ...

<table border="1"><tbody><tr><th> 시약의 이름 </th><th> 회사 </th><th> 카탈로그 번호 </th><th> 댓글 (옵션) </th></tr><tr><td> DMEM </td><td> 시그마 </td><td> D5671 </td><td></td></tr><tr><td> Dulbecco의 PBS </td><td> 시그마 </td><td> D5652 </td><td></td></tr><tr><td> Anti-mycotic/antibiotic 솔루션 </td><td> 시그마 </td><td> A5955 </td><td></td></tr><tr><td> 태아 소 혈청 </td><td> ThermoScientific </td><td> SH30070 </td><td></td></tr><tr><td> Viton의 격막 솔레노이드 밸브 </td><td> 맥매스터 카 </td><td> 4868K11 </td><td></td></tr><tr><td> 압력 변환기 </td><td> 오메가 엔지니어링 주식 회사 </td><td> PX302 - 200GV </td><td></td></tr><tr><td> 로드 셀 컨디셔너 </td><td> 앙코르 전자 주식 회사 </td><td> 4025-101 </td><td></td></tr><tr><td> 데이터 수집 (DAQ) 모듈 </td><td> 측정 컴퓨팅 </td><td> PMD1608 </td><td></td></tr></tbody></table>

design of a cyclic pressure bioreactor for the ex vivo study of aortic heart valves

좌심실과 대동맥 사이에 대동맥 밸브, 뇌실에 역류 방지, 단방향 혈액의 흐름을 허용합니다. 대동맥 밸브 전단지는 세포외 매트릭스 (ECM) 내에 정지 및 내피 세포 monolayer로 채워져 있습니다 침입형 세포로 구성되어 있습니다. 밸브는 거칠고, 역동적인 환경을 withstands하고 지속적으로 전단, 굴곡, 인장 및 압축에 노출됩니다. 연구 내피 중단하거나 중간 매트릭스 손상 1-3의 결과로 높은 기계적 응력 영역에서 발생하는 질병 밸브에 calcific 병변을 보이지 않고있다. 따라서, 그것은 역학 연구 대동맥 밸브 질환 4 발병의 주요 위험 요인으로 고혈압을 보여준 것은 놀라운 일이 아니다. 밸브 질환에 대해 현재 사용할 수있는 유일한 치료 방법은 bioprosthetic 또는 기계적 밸브 5 낡고 밸브의 수술 대신합니다. 물리적 스트레스에 대한 응답으로 밸브 생물학의 개선 이해 밸브 pathogenesis의 메커니즘을 명료하게하다 도움이 될 것이다. 차례로,이 같은 제약 개입이나 방지와 같은 비침습 요법의 개발에 도움을 줄 수 있습니다. 여러 bioreactors는 이전에 다음 ID로 기본 설계 또는 심장 밸브 6-9의 mechanobiology을 연구하기 위해 개발되었습니다. 타악기 bioreactors 또한 연골 10 골 11 방광을 포함하여 12 조직의 범위를 연구하기 위해 개발되었습니다. 이 작품의 목적은 증가 압력 하중에 대동맥 밸브 전단지의 생물 학적 반응을 명료하게하다하는 데 사용할 수있는 순환 압력 시스템을 개발하는 것이었습니다. 이 시스템은 샘플을 장소와 순환 압력, 압력 사이클의 타이밍을 제어하는​​ viton의 격막 솔레노이드 밸브, 전기 장치를 제어하는​​ 컴퓨터를 생산하는 아크릴 챔버로 구성되어. 압력은 압력 변환기를 사용하여 모니터링할 있었고, 신호는 부하 셀 컨디셔너를 사용하는 시설되었다. LabVIEW 프로그램은 적절한 속도로 시스템에 압축 공기를 펌프하는 아날로그 장치를 사용하여 압력을 규제. 시스템은 대동맥 밸브와 연결된 동적 transvalvular 압력 수준을 했었, 소우 치아 파의 밸브 개방을 묘사한 날카로운 압력 강하 다음 음절 연장 기간 동안 밸브에 걸쳐 존재하는 transvalvular 압력 구배의 전형적인 압력의 점진적 증가, 생산 수축기. LabVIEW 프로그램은 사용자가 주기적 압력의 크기와 주파수를 제어할 수있었습니다. 시스템은 생리와 병리 학적 압력 조건에 조직 샘플을 대상 수있었습니다. 이 장치는 심장 밸브가 로컬 기계 환경의 변화에​​ 대응하는 우리의 이해를 높이기 위해 사용할 수 있습니다.

Watch this Scientific Journal Video about Design of a Cyclic Pressure Bioreactor for the Ex Vivo Study of Aortic Heart Valves at JoVE.com

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

생리학 및 병리 학적 압력 조건에 심장 밸브 조직을 쓰는 수있는 순환 압력 생물 반응기는 설계되었습니다. LabVIEW 프로그램은 사용자가 압력 크기, 진폭 및 주파수를 제어할 수 있습니다. 이 장치는 심장 밸브 조직이나 격리 세포의 mechanobiology을 연구하는 데 사용할 수 있습니다.

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 ...

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

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15.6K 조회수.  Mississippi State University. 생리학 및 병리 학적 압력 조건에 심장 밸브 조직을 쓰는 수있는 순환 압력 생물 반응기는 설계되었습니다. LabVIEW 프로그램은 사용자가 압력 크기, 진폭 및 주파수를 제어할 수 있습니다. 이 장치는 심장 밸브 조직이나 격리 세포의 mechanobiology을 연구하는 데 사용할 수 있습니다.

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

Patient-specific Modeling of the Heart: Estimation of Ventricular Fiber Orientations

Patient-specific simulations of heart (dys)function aimed at personalizing cardiac therapy are hampered by the absence of in vivo imaging technology for clinically acquiring myocardial fiber orientations. The objective of this project was to develop a methodology to estimate cardiac fiber orientations from in vivo images of patient heart geometries. An accurate representation of ventricular geometry and fiber orientations was reconstructed, respectively, from high-resolution ex vivo structural magnetic resonance (MR) and diffusion tensor (DT) MR images of a normal human heart, referred to as the atlas. Ventricular geometry of a patient heart was extracted, via semiautomatic segmentation, from an in vivo computed tomography (CT) image. Using image transformation algorithms, the atlas ventricular geometry was deformed to match that of the patient. Finally, the deformation field was applied to the atlas fiber orientations to obtain an estimate of patient fiber orientations. The accuracy of the fiber estimates was assessed using six normal and three failing canine hearts. The mean absolute difference between inclination angles of acquired and estimated fiber orientations was 15.4 &deg;. Computational simulations of ventricular activation maps and pseudo-ECGs in sinus rhythm and ventricular tachycardia indicated that there are no significant differences between estimated and acquired fiber orientations at a clinically observable level.The new insights obtained from the project will pave the way for the development of patient-specific models of the heart that can aid physicians in personalized diagnosis and decisions regarding electrophysiological interventions.

A methodology to estimate ventricular fiber orientations from in vivo images of patient heart geometries for personalized modeling is described. Validation of the methodology performed using normal and failing canine hearts demonstrate that that there are no significant differences between estimated and acquired fiber orientations at a clinically observable level.

심장의 환자 별 모델링 : 심실 섬유 오리엔테이션의 추정

Patient-specific  simulations of heart (dys)function aimed at personalizing cardiac therapy are hampered  by the absence of in vivo imaging technology for ...

연구

생체공학

Design of a Biaxial Mechanical Loading Bioreactor for Tissue Engineering

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

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

조직 공학을위한 이축 기계 로딩 생물 반응기의 설계

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

Operation of a Benchtop Bioreactor

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

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

벤치 탑 생물 반응기의 운전

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

Characterization of Complex Systems Using the Design of Experiments Approach: Transient Protein Expression in Tobacco as a Case Study

Plants provide multiple benefits for the production of biopharmaceuticals including low costs, scalability, and safety. Transient expression offers the additional advantage of short development and production times, but expression levels can vary significantly between batches thus giving rise to regulatory concerns in the context of good manufacturing practice. We used a design of experiments (DoE) approach to determine the impact of major factors such as regulatory elements in the expression construct, plant growth and development parameters, and the incubation conditions during expression, on the variability of expression between batches. We tested plants expressing a model anti-HIV monoclonal antibody (2G12) and a fluorescent marker protein (DsRed). We discuss the rationale for selecting certain properties of the model and identify its potential limitations. The general approach can easily be transferred to other problems because the principles of the model are broadly applicable: knowledge-based parameter selection, complexity reduction by splitting the initial problem into smaller modules, software-guided setup of optimal experiment combinations and step-wise design augmentation. Therefore, the methodology is not only useful for characterizing protein expression in plants but also for the investigation of other complex systems lacking a mechanistic description. The predictive equations describing the interconnectivity between parameters can be used to establish mechanistic models for other complex systems.

We describe a design of experiments approach that can be used to determine and model the influence of transgene regulatory elements, plant growth and development parameters, and incubation conditions on the transient expression of monoclonal antibodies and reporter proteins in plants.

사례 연구로 담배에 과도 단백질 발현 : 실험 접근의 디자인을 사용하여 복잡한 시스템의 특성

Plants provide multiple benefits for the production of biopharmaceuticals including low costs, scalability, and safety. Transient expression offers the ...

Anatomically Realistic Neonatal Heart Model for Use in Neonatal Patient Simulators

Neonatal patient simulators (NPS) are artificial patient surrogates used in the context of medical simulation training. Neonatologists and nursing staff practice clinical interventions such as chest compressions to ensure patient survival in the case of bradycardia or cardiac arrest. The simulators used currently are of low physical fidelity and therefore cannot provide qualitative insight into the procedure of chest compressions. The embedding of an anatomically realistic heart model in future simulators enables the detection of cardiac output generated during chest compressions; this can provide clinicians with an output parameter, which can deepen the understanding of the effect of the compressions in relation to the amount of blood flow generated. Before this monitoring can be achieved, an anatomically realistic heart model must be created containing: two atria, two ventricles, four heart valves, pulmonary veins and arteries, and systemic veins and arteries. This protocol describes the procedure for creating such a functional artificial neonatal heart model by utilizing a combination of magnetic resonance imaging (MRI), 3D printing, and casting in the form of cold injection molding. Using this method with flexible 3D printed inner molds in the injection molding process, an anatomically realistic heart model can be obtained.

This protocol describes a procedure for creating functional artificial neonatal heart models by utilizing a combination of magnetic resonance imaging, 3D printing, and injection molding. The purpose of these models is for integration into the next generation of neonatal patient simulators and as a tool for physiological and anatomical studies.

신생아 환자 시뮬레이터에 사용 하기 위해 해부학 현실적인 신생아 심장 모델

Neonatal patient simulators (NPS) are artificial patient surrogates used in the context of medical simulation training. Neonatologists and nursing staff ...

Light-sheet Fluorescence Microscopy for the Study of the Murine Heart

Light-sheet fluorescence microscopy has been widely used for rapid image acquisition with a high axial resolution from micrometer to millimeter scale. Traditional light-sheet techniques involve the use of a single illumination beam directed orthogonally at sample tissue. Images of large samples that are produced using a single illumination beam contain stripes or artifacts and suffer from a reduced resolution due to the scattering and absorption of light by the tissue. This study uses a dual-sided illumination beam and a simplified CLARITY optical clearing technique for the murine heart. These techniques allow for deeper imaging by removing lipids from the heart and produce a large field of imaging, greater than 10 x 10 x 10 mm3. As a result, this strategy enables us to quantify the ventricular dimensions, track the cardiac lineage, and localize the spatial distribution of cardiac-specific proteins and ion-channels from the post-natal to adult mouse hearts with sufficient contrast and resolution.

This study uses a dual-sided illumination light-sheet fluorescence microscopy (LSFM) technique combined with optical clearing to study the murine heart.

Murine 심장 연구에 대 한 빛-시트 형광 현미경 검사 법

Light-sheet fluorescence microscopy has been widely used for rapid image acquisition with a high axial resolution from micrometer to millimeter scale. ...

A New Ex Vivo Model for the Evaluation of Endoscopic Submucosal Injection Material Performance

Increasing the performance of submucosal injection materials (SIMs) is important for endoscopic therapy of early gastrointestinal cancer. It is essential to establish an ex vivo model that can evaluate SIM performance accurately, for developing high-performance SIMs. In our previous study, we developed a new ex vivo model that can be used to evaluate the performance of various SIMs in detail by applying constant tension to the specimen&#39;s ends. We also confirmed that the proposed new ex vivo model allows accurate submucosal elevation height (SEH) measurement under uniform conditions and detailed comparisons of the performances of various types of SIMs. Here, we describe the new ex vivo model and explain the detailed setup methodology of this model. Since all parts of the new model were easy to obtain, the setup of the new model could be completed quickly. SEH of various SIMs could be measured more accurately by using the new model. The critical factor that determines SIM performance can be identified using the new model. SIM development speed will drastically increase after the factor has been identified.

A New Ex Vivo Model for the Evaluation of Endoscopic Submucosal Injection Material Performance

We developed a new ex vivo model that applies constant tension to the porcine gastric specimen. This development made it possible to evaluate the performance (the height and duration of the submucosal elevation) of various SIMs accurately.&#160; The detailed setup methodology of this new model is explained.

내 시경 Submucosal 주입 재료 성능 평가 대 한 새로운 Ex Vivo 모델

Increasing the performance of submucosal injection materials (SIMs) is important for endoscopic therapy of early gastrointestinal cancer. It is essential ...

Biaxial Mechanical Characterizations of Atrioventricular Heart Valves

Extensive biaxial mechanical testing of the atrioventricular heart valve leaflets can be utilized to derive&#160;optimal parameters used in constitutive models, which provide a mathematical representation of the mechanical function of those structures. This presented biaxial mechanical testing protocol involves (i) tissue acquisition, (ii) the preparation of tissue specimens, (iii) biaxial mechanical testing, and (iv) postprocessing of the acquired data. First, tissue acquisition requires obtaining porcine or ovine hearts from a local Food and Drug Administration-approved abattoir for later dissection to retrieve the valve leaflets. Second, tissue preparation requires using tissue specimen cutters on the leaflet tissue to extract a clear zone for testing. Third, biaxial mechanical testing of the leaflet specimen requires the use of a commercial biaxial mechanical tester, which consists of force-controlled, displacement-controlled, and stress-relaxation testing protocols to characterize the leaflet tissue&#39;s mechanical properties. Finally, post-processing requires the use of data image correlation techniques and force and displacement readings to summarize the tissue&#39;s mechanical behaviors in response to external loading. In general, results from biaxial testing demonstrate that the leaflet tissues yield a nonlinear, anisotropic mechanical response. The presented biaxial testing procedure is advantageous to other methods since the method presented here allows for a more comprehensive characterization of the valve leaflet tissue under one unified testing scheme, as opposed to separate testing protocols on different tissue specimens. The proposed testing method has its limitations in that shear stress is potentially present in the tissue sample. However, any potential shear is presumed negligible.

This protocol involves characterizations of atrioventricular valve leaflets with force-controlled, displacement-controlled, and stress-relaxation biaxial mechanical testing procedures. Results acquired with this protocol can be used for constitutive model development to simulate the mechanical behavior of functioning valves under a finite element simulation framework.

Biaxial 기계 Characterizations 것 심장 밸브의

Extensive biaxial mechanical testing of the atrioventricular heart valve leaflets can be utilized to derive&#160;optimal parameters used in constitutive ...

A Friction Testing-Bioreactor Device for Study of Synovial Joint Biomechanics, Mechanobiology, and Physical Regulation

In primary osteoarthritis (OA), normal 'wear and tear' associated with aging inhibits the ability of cartilage to sustain its load-bearing and lubrication functions, fostering a deleterious physical environment. The frictional interactions of articular cartilage and synovium may influence joint homeostasis through tissue level wear and cellular mechanotransduction. To study these mechanical and mechanobiological processes, a device capable of replicating the motion of the joint is described. The friction testing device controls the delivery of reciprocal translating motion and normal load to two contacting biological counterfaces. This study adopts a synovium-on-cartilage configuration, and friction coefficient measurements are presented for tests performed in a phosphate-buffered saline (PBS) or synovial fluid (SF) bath. The testing was performed for a range of contact stresses, highlighting the lubricating properties of SF under high loads. This friction testing device can be used as a biomimetic bioreactor for studying the physical regulation of living joint tissues in response to applied physiologic loading associated with diarthrodial joint articulation.

The present protocol describes a friction testing device that applies simultaneous reciprocal sliding and normal load to two contacting biological counterfaces.

마찰 테스트 - 활막 관절 생물 역학, Mechanobiology 및 물리적 조절 연구를위한 생물 반응기 장치

In primary osteoarthritis (OA), normal 'wear and tear' associated with aging inhibits the ability of cartilage to sustain its load-bearing and lubrication ...

Procurement and Decellularization of Rat Hindlimbs Using an Ex Vivo Perfusion-Based Bioreactor for Vascularized Composite Allotransplantation

Patients with severe traumatic injuries and tissue loss require complex surgical reconstruction. Vascularized composite allotransplantation (VCA) is an evolving reconstructive avenue for transferring multiple tissues as a composite subunit. Despite the promising nature of VCA, the long-term immunosuppressive requirements are a significant limitation due to the increased risk of malignancies, end-organ toxicity, and opportunistic infections. Tissue engineering of acellular composite scaffolds is a potential alternative in reducing the need for immunosuppression. Herein, the procurement of a rat hindlimb and its subsequent decellularization using sodium dodecyl sulfate (SDS) is described. The procurement strategy presented is based upon the common femoral artery. A machine perfusion-based bioreactor system was constructed and used for ex vivo decellularization of the hindlimb. Successful perfusion decellularization was performed, resulting in a white translucent-like appearance of the hindlimb. An intact, perfusable, vascular network throughout the hindlimb was observed. Histological analyses showed the removal of nuclear contents and the preservation of tissue architecture across all tissue compartments.

Procurement and Decellularization of Rat Hindlimbs Using an Ex Vivo Perfusion-Based Bioreactor for Vascularized Composite Allotransplantation

We describe the surgical technique and decellularization process for composite rat hindlimbs. Decellularization is conducted using low-concentration sodium dodecyl sulfate through an ex vivo machine perfusion system.

혈관화된 복합 동종 이식을 위한 생체 내 관류 기반 생물반응기를 사용한 쥐 뒷다리의 조달 및 탈세포화

Patients with severe traumatic injuries and tissue loss require complex surgical reconstruction. Vascularized composite allotransplantation (VCA) is an ...

의 순환 압력 생물 반응기 설계 예 VIVO 학습