著者は、原稿を準備するための支援システムとValtresaのマイルズの設計と製造とその支援のためのシャッドSchipkeとダニエルチェサーに感謝しています。

1。組織の収穫と準備<ol><li>大動脈弁はすぐに死の後にこれ以上の120を超えるポンドの重量を量る成人豚から収集する必要があります。 </li><li>滅菌リン酸で二回バルブを洗浄する生理食塩水（PBS）と氷の上で研究室への輸送は、バッファリング。 </li><li>後続のすべての手順は、無菌条件下で実行する必要があります。 </li><li>そのチラシが裂けたり、石灰化、変性の兆候を示していないことを確認します。アニュラスからの距離の1 / 3をカットすることで大動脈基部からチラシを取り外します。 </li><li>場所のシックスウェルプレートの個々のウェルのチラシと37℃、5％CO 2で1％anti-biotic/anti-mycoticソリューションおよび10％ウシ胎児血清を添加した3ミリリットルダルベッコ変法イーグル培地で一晩インキュベートする。 </li><li>別の、分離した細胞は6ウェル培養プレートに播種し、加圧装置で使用することができますように。以前に13、14を説明するように弁内皮細胞と間質細胞の単離を行うことができます。 </li></ol> 2。圧力研究<ol><li>カスタムメイドの圧力システムは、大動脈弁の組織15周期的圧力のmechanobiological効果を研究するように設計されています。 </li><li>コンピュータにログオンし、LabVIEWのプログラム（図1）を開きます。 </li><li>キャリブレーション： <ol><li>実験前に、システムが適切に校正されるべきである。 </li><li>回路基板に電源を接続します。これにより、チャンバ内へと外の空気の流れを制御するソレノイドバルブに電力を供給します。 </li><li>圧縮空気がシステムに接続されていることを確認し、完全な速度に空気の供給を開きます。 </li><li>信号増幅器の電源をオンにします。電圧測定値が0.00であることを確認してください。必要に応じて調整する</li><li> LabVIEWインタフェースは、&quot;TEST / RECORD&quot;とマークされたスイッチがあります。スイッチが&quot;TEST&quot;に設定されていることを確認してください。入口電磁弁を開くには&quot;エアサプライ&quot;とマークされたボタンをクリックします。 </li><li>ガス圧力レギュレータを使用して、1 PSIで圧縮空気とチャンバーを加圧する。チャンバー内の圧力は、チャンバの後端-プレート上にあるデジタル圧力計を使用して読み取ることができます。圧力が平衡化されていると、信号増幅器から電圧の読み値を記録。 2、3、4、5 PSIについて、この手順を繰り返します。 </li><li>圧力対電圧の検量線を作成します。圧力はPSIからmmHgに変換する必要があります。グラフから方程式は、LabVIEWプログラムのコードに配置することができます</li></ol></li><li>圧力室からアルミフロントプレートを取り外し、70％エタノールでチャンバーをスプレー。残留エタノールガスが放散できるように、最低10分間放置。 </li><li>室にリーフレットのサンプルを含む6ウェルプレートを置き、フロントエンドプレートを交換してください。シールは手で4つのねじ山付きロッド（エンドプレートの各隅にある）上にあるナットを締めて、気密であることを確認してください。 37℃インキュベーターに圧力室を配置。圧力室の概略図を図2に示します。 </li><li>インタフェースは、圧縮空気の入力と出力の間にシステムサイクル時間を提供するためにユーザに促します。これらは、0.6秒に設定され、1Hzの周波数で、それぞれ、収縮期血圧および拡張期の条件を模倣するために0.4秒してください。また、ユーザーは、データファイルのパスを入力する必要があります。 </li><li> LabVIEWでは、&quot;RECORD&quot;のトグル&quot;TEST / RECORD&quot;を実行して切り替える]をクリックします。 </li><li>圧力は、LabVIEWのインターフェイス上でグラフを用いて所望のレベルにあることを確認してください。圧力は、ガス圧力調整器を使用して調整することができます。 </li><li>時間の希望の長さのためのプログラムを実行します。 </li><li>実験が完了すると、は、LabVIEW上でストップボタンをクリックして空気の供給をオフにし、圧力室に排気バルブを開く。 </li><li>チャンバーからフロントエンドプレートを取り外し、サンプルを含む6ウェルプレートを取得。サンプルは遺伝子発現、タンパク質発現、組織学、機械的特性等について分析することができる</li></ol> 3。代表的な結果： 圧力システムは正常血圧の下で観察された最大圧較圧力をシミュレートすることができる、I期およびII期血圧の条件を上演。しかし、圧力は、生体内で実質的にゼロである収縮期圧較差を、模倣することができませんでした。周波数は0.6秒と0.4秒の排気時間の空気入口の時間で、1Hzで維持されます。システムから得られた正常と高い圧力の条件の代表的な圧力波形を図3に見ることができます。 <img src="/files/ftp_upload/3316/3316fig1.jpg" alt="図1"/> 図1：LabVIEWのインターフェースのスクリーンショット。 <img src="/files/ftp_upload/3316/3316fig2.jpg" alt="図2"/> 図2：圧力室の圧力室A.等角図の模式図、圧力室のB.サイドビュー。圧力室のC.上から見た図。 <img src="/files/ftp_upload/3316/3316fig3.jpg" alt="図3"/> 図3：（A）正常血圧、（B）私は高血圧ステージ、および（C）ステージII高血圧の条件での圧力室内の圧力のシミュレーションのグラフ。

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利害の衝突は宣言されません。

圧力システムが正常に拡張期圧較圧力の代表だった周期圧力に大動脈弁尖を露呈した。圧力は40 mmHgにドロップされたとしてしかし、それは、収縮期圧較圧力を模倣することができませんでした。圧較圧力は上行大動脈の圧力と左心室の間の差である。拡張期の間に、バルブが閉じているときに、圧力差は、正常血圧の条件と90 mmHgの下で80mmHgされており、I期およびII期の高血圧は、それぞれ?...

<table border="1"><tbody><tr><th>試薬の名前</th><th>会社</th><th>カタログ番号</th><th>コメント（省略可能） </th></tr><tr><td> DMEM </td><td>シグマ</td><td> D5671 </td><td></td></tr><tr><td>ダルベッコPBS </td><td>シグマ</td><td> D5652 </td><td></td></tr><tr><td> Anti-mycotic/antibioticソリューション</td><td>シグマ</td><td> A5955 </td><td></td></tr><tr><td>ウシ胎仔血清</td><td> ThermoScientific </td><td> SH30070 </td><td></td></tr><tr><td>バイトンのダイヤフラム電磁弁</td><td>マクマスターカー</td><td> 4868K11 </td><td></td></tr><tr><td>圧力トランスデューサー</td><td>オメガエンジニアリング株式会社</td><td> PX302 - 200GV </td><td></td></tr><tr><td>ロードセルのコンディショナー</td><td>アンコールエレクトロニクス、（株） </td><td> 4025-101 </td><td></td></tr><tr><td>データ集録（DAQ）モジュール</td><td>測定コンピューティング</td><td> PMD1608 </td><td></td></tr></tbody></table>

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

左心室と大動脈の間にある大動脈弁は、心室に逆流を防止する、単方向の血流が可能になります。大動脈弁尖は、細胞外マトリックス（ECM）内に懸濁し、そして内皮細胞単層で裏打ちされています間質細胞で構成されています。バルブは、過酷な、動的な環境に耐え、絶えずせん断、屈曲、緊張、および圧縮にさらされています。研究は、内皮中断や間質マトリックスの損傷1-3の結果として、高い機械的応力の領域で発生する病気の弁に石灰化病変を示している。したがって、それは疫学的研究は、大動脈弁疾患4の発症の主要な危険因子であることが高血圧を示していることは驚くべきことではない。 弁疾患のため現在入手可能な唯一の治療法の選択肢はbioprostheticまたは機械的なバルブ5と病気の弁の手術の代替品です。物理的なストレスに応答して、バルブの生物学の理解の向上には、バルブの病因のメカニズム解明に役立つだろう。ターンでは、このような薬剤介入や予防などの非侵襲的な治療法の開発に役立つ可能性があります。いくつかのバイオリアクターは、以前はネイティブまたは人工心臓弁6-9のmechanobiologyを研究するために開発されている。拍動性バイオリアクターは、軟骨10、骨11、膀胱12を含む組織の範囲を研究するために開発されている。この作業の目的は、上昇圧力荷重に対する大動脈弁尖の生物学的応答を解明するために使用することができる周期的圧力のシステムを開発することでした。 システムはサンプルを配置し、電気機器を制御するために周期的な圧力、圧力サイクルのタイミングを制御するためにバイトンダイヤフラム電磁弁、およびコンピュータを生産するのアクリルチャンバーから成っていた。圧力は圧力変換器を用いてモニターし、信号はロードセルのコンディショナーを使用して調整した。 LabVIEWプログラムは、適切な速度でシステムに圧縮空気をポンプするために、アナログデバイスを使用して圧力を調節。システムは、大動脈弁に関連付けられている動的な圧較圧レベルを模倣し、鋸歯状の波がでバルブの開度を描いた急激な圧力降下が続く拡張期の間にバルブ前後存在していることを圧較圧力勾配の典型的な圧力が徐々に増加し、生産収縮。 LabVIEWプログラムは、ユーザーが周期的圧力の大きさと周波数を制御することを可能にしました。システムは、生理学的および病理学的圧力の条件に組織サンプルを施すことができた。このデバイスは、心臓弁は、ローカルの機械環境の変化に対応方法についての我々の理解を高めるために使用することができます。

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

生理学的および病理学的圧力の条件に心臓弁組織を施すことのできる周期的圧力のバイオリアクターを設計されています。 LabVIEWプログラムは、ユーザーが圧力の大きさ、振幅と周波数を制御することができます。このデバイスは、心臓弁の組織または単離された細胞のmechanobiologyを研究するために使用することができます。

のための周期的圧力のバイオリアクターの設計生体外で</em大動脈心臓弁の>研究

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 ビュー.  Mississippi State University. 生理学的および病理学的圧力の条件に心臓弁組織を施すことのできる周期的圧力のバイオリアクターを設計されています。 LabVIEWプログラムは、ユーザーが圧力の大きさ、振幅と周波数を制御することができます。このデバイスは、心臓弁の組織または単離された細胞のmechanobiologyを研究するために使用することができます。

ビデオ: 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.

ハートの患者固有のモデリング：心室繊維配向の推定

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

生物工学

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.

組織工学のための二軸メカニカルローディングバイオリアクターの設計

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.

ベンチトップリアクターの操作

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.

ケーススタディとして、タバコにおける一過性タンパク質発現：実験アプローチのデザインを使用した複雑系のキャラクタリゼーション

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.

新生児患者シミュレータでの解剖学的に現実的な新生児心臓モデル

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.

マウス心臓の研究のための光シート蛍光顕微鏡

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.

内視鏡的粘膜下注入材料の性能の評価のための新しいEx Vivoモデル

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.

房室弁の二軸の機械特性

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.

滑膜関節バイオメカニクス、メカノバイオロジー、物理調節の研究のための摩擦試験バイオリアクター装置

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.

血管化複合同種移植のための 生体外 灌流ベースのバイオリアクターを用いたラット後肢の調達と脱細胞化

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

のための周期的圧力のバイオリアクターの設計生体外で研究