部の軍 #W81XWH-08-1-0587、#W81XWH-15-1-0006。ボール州立大学 2010年熱望するグラント。

<ol>
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A., Moradi, M. H., Crowe, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> PID control: new identification and design methods. , 543 (2005).</li><li>Craig, R. R., Bampton, M. C. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coupling+of+substructures+for+dynamics+analysis.">Coupling of substructures for dynamics analysis.</a> American Institute of Aeronautics and Astronautics Journal. 6, 1313-1319 (1968).</li><li>Wasfy, T. M., Noor, A. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Computational+strategies+for+flexible+multibody+systems.">Computational strategies for flexible multibody systems.</a> Appl Mech Rev. 56, 553-613 (2003).</li><li>Kadaba, M. P., Ramakrishnan, H. k., Wootten, M. 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著者は、彼らは競合する金銭的な利益があることを宣言します。

本研究の目的は、高負荷活動期の脛骨の変形を決定する非侵襲的な方法を開発するでした。衝撃荷重により脛骨ひずみ分布の定量化は、脛骨疲労骨折のより良い理解に します。この研究では、サブジェクト固有の筋骨格モデルを開発したとコンピューター シミュレーションは実験室の設定で実行されるドロップ着陸の動きを複製する実行されました。ドロップ着陸高さの脛骨のひずみに及?...

ストレス骨折などの骨のストレス傷害、深刻な過剰使用の傷害の回復の長い期間を必要とする、重要な医療コスト1,2を発生させず。ストレス骨折は一般的な運動および軍事集団の両方。すべてのスポーツ関連傷害、ストレス骨折合計3の 10% を占める。特に、陸上競技選手の高い傷害率 204の顔します。兵士はまたストレス骨折率が高いを経験します。例えば、米陸軍1に対して 6% 負傷率が報告された、イスラエルの軍隊5で 31% 負傷率が報告されました。すべての報告されたストレス骨折の中では、脛骨疲労骨折は最も一般的な 1 つ6,7,8です。
スポーツと脛骨疲労骨折のリスクが高いと身体トレーニングは、高地の影響 (例えば、ジャンプ、着地、切削) に通常関連付けられます。移動中に足が地面に当たったとき体に地面の衝撃が適用されます。筋骨格系及び履物にてこの衝撃を消散します。骨格系は、地面の影響9を吸収する力を適用する筋肉をできるようにレバーのシリーズとして提供しています。脚の筋肉は十分に地面への影響を減らすことはできません、下半身のボーンは残留力を吸収する必要があります。骨の構造は、この過程での変形を経験します。残留への影響力の吸収を繰り返し、骨の microdamages が蓄積し、疲労骨折になる可能性があります。日付、骨に関連した情報を外部地上衝撃力への反作用は制限されています。脛骨骨が動的な運動の中に高い衝撃力で導入する機械負荷に応答する方法を研究することが重要です。脛骨疲労骨折のメカニズムの理解につながる可能性高負荷活動中に脛骨骨変形を調べるします。
骨変形体内測定する従来技術は、インストルメント化されたひずみゲージ10、11,12,13,14,15に依存します。骨表面にひずみゲージを移植する手術が必要です。侵襲により生体内での研究は、ボランティアの小さなサンプルによって制限されます。また、ひずみゲージのみ骨表面の小さな領域を監視できます。最近では、骨の歪みを分析してコンピューター シミュレーションを利用した非侵襲的な方法は、導入された16,17だった。この方法論は、筋骨格系のモデル化と計算機シミュレーションを結合する能力、人間の動きの間に骨の歪みを勉強するには
筋骨格系モデルは骨格や骨格筋によって表されます。スケルトンは、剛体または非変形体である骨セグメントで構成されます。骨格筋は、プログレッシブ ・積分・微分 (PID) アルゴリズムを使用してコント ローラーとしてモデル化されます。3 項の PID 制御は、出力精度18を改善するために推定でエラーを使用します。本質的に、筋肉を表す PID コント ローラーは、時間をかけて筋肉の長さ変化をもたらすに必要な力を開発することによって身体の動きを複製しようとします。PID コント ローラーは、長さ/時間カーブの動きを再現するため力を変更するのにエラーを使用します。このシミュレーションでは、スケルトンを移動し、体の動きを作り出すのために協力するすべての筋肉を調整するための実現可能な解を作成します。
骨格筋骨格モデルに 1 つまたは複数のセグメントは、変形の測定を許可するように、柔軟な体としてモデル化できます。例えば、脛骨骨は要素とノードの数で構成される有限数の要素に分けることが。有限要素 (FE) の分析を通して、柔軟な脛骨の力学的負荷の影響を調べることができます。有限要素解析では、時間をかけて個々 の要素の読み込み応答を計算します。骨の要素およびノードの増加の数、有限要素解析の計算時間が大幅に増加します。
柔軟な体変形の正確な評価と計算コストを減らすためには、モーダル解析が開発し、自動車や航空宇宙産業19,20の内で使用されます。個々 の FE 要素のレスポンス時間領域における機械的負荷を分析する代わりにこのプロシージャは周波数の異なる振動周波数に基づいてオブジェクトの力学的応答を評価します。このメソッドは変形20の正確な測定を提供しながら, 計算時間の大幅な削減の結果します。モーダル解析は、自動車、航空宇宙の分野で機械的疲労研究に広く使用されています、このメソッドのアプリケーション非常に限定されている人間の動き科学。アル Nazerら、二足歩行運動中の脛骨の変形を調べるため、モーダルの有限要素解析と結果16,17を奨励することを報告します。ただし、その方法でした; シミュレーションを駆動する実験から限られた運動学的データのみを使用して影響を大幅実がない地面の影響力のシミュレーションを支援するために使用します。このアプローチは歩行など負荷の少ない遅い動きの勉強のための合理的かもしれませんが、負荷の動きは高地を研究する実行可能なソリューションではありません。したがって、高衝撃活動中に下半身の骨反応を調べるためにそれは以前に報告したメソッドに関連付けられている制限に対処するための革新的なアプローチを開発することが欠かせません。具体的には、正確な実験的運動学的データと実を利用する方法地面衝撃力を開発する必要があります。したがって、本研究の目的は、インパクト活動中に脛骨の歪みを調査するモーダル FE 解析マルチボディの動的シミュレーションを実行するサブジェクト固有の筋骨格モデルを開発することでした。メソッドをテストするさまざまな高さからドロップ着陸によって表される動的衝撃運動が選ばれました。

<table border="0" cellpadding="0" cellspacing="0" width="575">
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:143px;">CT Scanner</td>
			<td style="width:123px;">GE Medical System</td>
			<td style="width:107px;">N/A</td>
			<td style="width:203px;">Light Speed VCT. For performing tibia CT scan.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Motion Capture System</td>
			<td>Vicon Inc</td>
			<td>N/A</td>
			<td>Vicon FX40 high speed cameras. For performing 3D motion capture.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Force plates</td>
			<td>AMTI Inc</td>
			<td>N/A</td>
			<td>Collecting 3D ground reaction forces</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Vicon Nexus</td>
			<td>Vicon Inc</td>
			<td>N/A</td>
			<td>Motion capture software program. For processing visual marker trajectory data.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Visual 3D</td>
			<td>C-Motion Inc</td>
			<td>N/A</td>
			<td>Biomechanics analysis software. For computing 3D kinematics and kinetics of human movements.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">MATLAB</td>
			<td>Mathworks Inc</td>
			<td>N/A</td>
			<td>Computer programming software. For performing raw data filtering, data conversion, and data processing.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">ADAMS 2012</td>
			<td>MSC Software Inc</td>
			<td>N/A</td>
			<td>Multibody dynamic computer simulation program.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">LifeMOD</td>
			<td>Lifemodeler Inc</td>
			<td>N/A</td>
			<td>A software Plug-in in ADAMS. For building human body musculo-skeletal models.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">MIMICS 13</td>
			<td>Materialise Inc</td>
			<td>N/A</td>
			<td>Image processing program. A 3D modeling tool to process imaging data. For creating 3D tibia model from CT scans.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">MARC 2012</td>
			<td>MSC Software Inc</td>
			<td>N/A</td>
			<td>Finite element analysis software. For performing volumn meshing, generating tibia FE model, and running modal FE analysis.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">SPSS 19</td>
			<td>IBM Inc</td>
			<td>N/A</td>
			<td>Statistical analysis software.</td>
		</tr>
	</tbody>
</table>

subject-specific musculoskeletal model for studying bone strain during dynamic motion

骨ストレス傷害、スポーツや軍事訓練。トレーニング中に繰り返し大規模な地面の影響力が原因であります。下半身の骨の変形骨ストレス傷害のメカニズムを理解する力の高地の効果を決定することが不可欠です。従来のひずみゲージの測定は脛骨変形生体内での研究に使用されています。このメソッドは、プロシージャの侵襲性、少数の被験者と小さな骨表面積から限られた歪みデータの関与などの制限に関連付けられます。現在の研究は、高衝撃荷重条件下における脛骨骨歪みの研究への新しいアプローチをご紹介する予定です。健康な男性 (19 年、80 kg、1,800 mm) を表す件名固有の筋骨格系モデルが作成されました。柔軟な有限要素脛骨モデルは、被験者の右脛骨のコンピューター断層撮影 (CT) スキャンに基づいて作成されました。研究所モーション キャプチャを行った (26, 39、52 cm) 高さが異なるからドロップ着陸の運動学と地盤の反力を得る。ドロップ着陸中の脛骨の歪みを数値化する柔軟な脛骨のモーダル解析と組み合わせて多動的なコンピューター シミュレーションを行った。計算脛骨ひずみデータ以前生体内研究とよく一致しました。脛骨疲労骨折の傷害メカニズムの理解を深めることにつながる大規模コホートのインパクト活動中に脛骨の骨の歪みを勉強するこの非侵襲的アプローチを適用できることは明らかです。

健康な白人男性 (19 歳、高さ 1,800 mm、質量 80 kg) 研究のために志願しました。データ収集の前に件名レビュー、および、研究に参加する前に大学制度検討委員会によって承認された同意書をサインします。ヘルシンキ宣言の下で実験を行った。実験は次のプロトコルに基づいて行われました。
順方向の動的シミュレーショ?...

Watch this Scientific Journal Video about Subject-specific Musculoskeletal Model for Studying Bone Strain During Dynamic Motion at JoVE.com

動的運動中の骨の歪みを研究するための被験者固有の筋骨格モデル |バイオエンジニアリング |ビデオ

Subject-specific Musculoskeletal Model for Studying Bone Strain During Dynamic Motion

着陸時に下半身の骨は大きな機械的負荷を経験し、変形します。骨の変形の影響に関連付けられている骨ストレス傷害のメカニズムを理解するための測定が不可欠です。対象特定筋骨格モデリングと有限要素解析を統合する手法は、ダイナミックな動きの中に脛骨の歪みを測定する使用されます。

サブジェクト固有筋骨格モデル動的モーションの間に骨の歪みを勉強のため

Bone stress injuries are common in sports and military trainings. Repetitive large ground impact forces during training could be the cause. It is ...

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Unit 1

Transformations of Stress and Strain

Musculoskeletal System

SCIENTISTS IN ACTION

9.6K ビュー.  Ball State University. 着陸時に下半身の骨は大きな機械的負荷を経験し、変形します。骨の変形の影響に関連付けられている骨ストレス傷害のメカニズムを理解するための測定が不可欠です。対象特定筋骨格モデリングと有限要素解析を統合する手法は、ダイナミックな動きの中に脛骨の歪みを測定する使用されます。

ビデオ: Subject-specific Musculoskeletal Model for Studying Bone Strain During Dynamic Motion

Microfabricated Platforms for Mechanically Dynamic Cell Culture

The ability to systematically probe in vitro cellular response to combinations of mechanobiological stimuli for tissue engineering, drug discovery or fundamental cell biology studies is limited by current bioreactor technologies, which cannot simultaneously apply a variety of mechanical stimuli to cultured cells. In order to address this issue, we have developed a series of microfabricated platforms designed to screen for the effects of mechanical stimuli in a high-throughput format. In this protocol, we demonstrate the fabrication of a microactuator array of vertically displaced posts on which the technology is based, and further demonstrate how this base technology can be modified to conduct high-throughput mechanically dynamic cell culture in both two-dimensional and three-dimensional culture paradigms.

In this protocol, we demonstrate the fabrication of a microactuator array of vertically displaced posts on which the technology is based, and how this base technology can be modified to conduct high-throughput mechanically dynamic cell culture in both two-dimensional and three-dimensional culture paradigms.

機械的にダイナミックな細胞培養のための微細加工プラットフォーム

The ability to systematically probe in vitro cellular response to combinations of mechanobiological stimuli for tissue engineering, drug discovery or ...

生物工学

Microfluidic Mixers for Studying Protein Folding

The process by which a protein folds into its native conformation is highly relevant to biology and human health yet still poorly understood. One reason for this is that folding takes place over a wide range of timescales, from nanoseconds to seconds or longer, depending on the protein1. Conventional stopped-flow mixers have allowed measurement of folding kinetics starting at about 1 ms. We have recently developed a microfluidic mixer that dilutes denaturant ~100-fold in ~8 &mu;s2. Unlike a stopped-flow mixer, this mixer operates in the laminar flow regime in which turbulence does not occur. The absence of turbulence allows precise numeric simulation of all flows within the mixer with excellent agreement to experiment3-4.
Laminar flow is achieved for Reynolds numbers Re &le;100. For aqueous solutions, this requires micron scale geometries. We use a hard substrate, such as silicon or fused silica, to make channels 5-10 &mu;m wide and 10 &mu;m deep (See Figure 1). The smallest dimensions, at the entrance to the mixing region, are on the order of 1 &mu;m in size. The chip is sealed with a thin glass or fused silica coverslip for optical access. Typical total linear flow rates are ~1 m/s, yielding Re~10, but the protein consumption is only ~0.5 nL/s or 1.8 &mu;L/hr. Protein concentration depends on the detection method: For tryptophan fluorescence the typical concentration is 100 &mu;M (for 1 Trp/protein) and for FRET the typical concentration is ~100 nM.
The folding process is initiated by rapid dilution of denaturant from 6 M to 0.06 M guanidine hydrochloride. The protein in high denaturant flows down a central channel and is met on either side at the mixing region by buffer without denaturant moving ~100 times faster (see Figure 2). This geometry causes rapid constriction of the protein flow into a narrow jet ~100 nm wide. Diffusion of the light denaturant molecules is very rapid, while diffusion of the heavy protein molecules is much slower, diffusing less than 1 &mu;m in 1 ms. The difference in diffusion constant of the denaturant and the protein results in rapid dilution of the denaturant from the protein stream, reducing the effective concentration of the denaturant around the protein. The protein jet flows at a constant rate down the observation channel and fluorescence of the protein during folding can be observed using a scanning confocal microscope5.

In this work we explain the fabrication and use of a microfluidic mixer capable of mixing two solutions in ~8 &mu;s. We also demonstrate the use of these mixers with spectroscopic detection using UV fluorescence and fluorescence resonance energy transfer (FRET).

タンパク質の折り畳みを研究するためのマイクロ流体ミキサー

The process by which a protein folds into its native conformation is highly relevant to biology and human health yet still poorly understood. One reason ...

Correlative Microscopy for 3D Structural Analysis of Dynamic Interactions

Cryo-electron tomography (cryoET) allows 3D visualization of cellular structures at molecular resolution in a close-to-physiological state1. However, direct visualization of individual viral complexes in their host cellular environment with cryoET is challenging2, due to the infrequent and dynamic nature of viral entry, particularly in the case of HIV-1. While time-lapse live-cell imaging has yielded a great deal of information about many aspects of the life cycle of HIV-13-7, the resolution afforded by live-cell microscopy is limited (~ 200 nm). Our work was aimed at developing a correlation method that permits direct visualization of early events of HIV-1 infection by combining live-cell fluorescent light microscopy, cryo-fluorescent microscopy, and cryoET. In this manner, live-cell and cryo-fluorescent signals can be used to accurately guide the sampling in cryoET. Furthermore, structural information obtained from cryoET can be complemented with the dynamic functional data gained through live-cell imaging of fluorescent labeled target.
In this video article, we provide detailed methods and protocols for structural investigation of HIV-1 and host-cell interactions using 3D correlative high-speed live-cell imaging and high-resolution cryoET structural analysis. HeLa cells infected with HIV-1 particles were characterized first by confocal live-cell microscopy, and the region containing the same viral particle was then analyzed by cryo-electron tomography for 3D structural details. The correlation between two sets of imaging data, optical imaging and electron imaging, was achieved using a home-built cryo-fluorescence light microscopy stage. The approach detailed here will be valuable, not only for study of virus-host cell interactions, but also for broader applications in cell biology, such as cell signaling, membrane receptor trafficking, and many other dynamic cellular processes.

We describe a correlative microscopy method that combines high-speed 3D live-cell fluorescent light microscopy and high-resolution cryo-electron tomography. We demonstrate the capability of the correlative method by imaging dynamic, small HIV-1 particles interacting with host HeLa cells.

ダイナミックな相互作用の3次元構造解析のための相関顕微鏡

Cryo-electron tomography (cryoET) allows 3D visualization of cellular structures at molecular resolution in a close-to-physiological state1. However, ...

Home-Based Monitor for Gait and Activity Analysis

Current outcomes in neuromuscular disorder clinical trials include motor function scales, timed tests, and strength measures performed by trained clinical evaluators. These measures are slightly subjective and are performed during a visit to a clinic or hospital and constitute therefore a point assessment. Point assessments can be influenced by daily patient condition or factors such as fatigue, motivation, and intercurrent illness. To enable home-based monitoring of gait and activity, a wearable magneto-inertial sensor (WMIS) has been developed. This device is a movement monitor composed of two very light watch-like sensors and a docking station. Each sensor contains a tri-axial accelerometer, gyroscope, magnetometer, and a barometer that record linear acceleration, angular velocity, the magnetic field of the movement in all directions, and barometric altitude, respectively. The sensors can be worn on the wrist, ankle, or wheelchair to record the subject&#8217;s movements during the day. The docking station enables data uploading and recharging of sensor batteries during the night. Data are analyzed using proprietary algorithms to compute parameters representative of the type and intensity of the performed movement. This WMIS can record a set of digital biomarkers, including cumulative variables, such as total number of meters walked, and descriptive gait variables, such as the percentage of the most rapid or longest stride that represents the top performance of patient over a predefined period of time.

This innovative device uses magneto-inertial sensors to permit gait and activity analysis in uncontrolled environments. Currently in the qualification process as an outcome measure in the European Medical Agency, one of the applications will be to serve as a clinical endpoint in clinical trials in neuromuscular diseases.

歩行とアクティビティ分析のためのホームベースのモニター

Current outcomes in neuromuscular disorder clinical trials include motor function scales, timed tests, and strength measures performed by trained clinical ...

Calvarial Model of Bone Augmentation in Rabbit for Assessment of Bone Growth and Neovascularization in Bone Substitution Materials

The basic principle of the rabbit calvarial model is to grow new bone tissue vertically on top of the cortical part of the skull. This model allows assessment of bone substitution materials for oral and craniofacial bone regeneration in terms of bone growth and neovascularization support. Once animals are anesthetized and ventilated (endotracheal intubation), four cylinders made of polyether ether ketone (PEEK) are screwed onto the skull, on both sides of the median and coronal sutures. Five intramedullary holes are drilled within the bone area delimited by each cylinder, allowing influx of bone marrow cells. The material samples are placed into the cylinders which are then closed. Finally, the surgical site is sutured, and animals are awaken. Bone growth may be assessed on live animals by using microtomography. Once animals are euthanized, bone growth and neovascularization may be evaluated by using microtomography, immune-histology and immunofluorescence. As the evaluation of a material requires maximum standardization and calibration, the calvarial model appears ideal. Access is very easy, calibration and standardization are facilitated by the use of defined cylinders and four samples may be assessed simultaneously. Furthermore, live tomography may be used and ultimately a large decrease in animals to be euthanized may be anticipated.

Here we present a surgical protocol in rabbits with the aim to assess bone substitution materials in terms of bone regeneration capacities. By using PEEK cylinders fixed onto rabbit skulls, osteoconduction, osteoinduction, osteogenesis and vasculogenesis induced by the materials may be evaluated either on live or euthanized animals.

骨置換材料における骨成長と新生血管の評価のためのウサギにおける骨増強の卵子モデル

The basic principle of the rabbit calvarial model is to grow new bone tissue vertically on top of the cortical part of the skull. This model allows ...

A Human 3D Extracellular Matrix-Adipocyte Culture Model for Studying Matrix-Cell Metabolic Crosstalk

The extracellular matrix (ECM) plays a central role in regulating tissue homeostasis, engaging in crosstalk with cells and regulating multiple aspects of cellular function. The ECM plays a particularly important role in adipose tissue function in obesity, and alterations in adipose tissue ECM deposition and composition are associated with metabolic disease in mice and humans. Tractable in vitro models that permit dissection of the roles of the ECM and cells in contributing to global tissue phenotype are sparse. We describe a novel 3D in vitro model of human ECM-adipocyte culture that permits study of the specific roles of the ECM and adipocytes in regulating adipose tissue metabolic phenotype. Human adipose tissue is decellularized to isolate ECM, which is subsequently repopulated with preadipocytes that are then differentiated within the ECM into mature adipocytes. This method creates ECM-adipocyte constructs that are metabolically active and retain characteristics of the tissues and patients from which they are derived. We have used this system to demonstrate disease-specific ECM-adipocyte crosstalk in human adipose tissue. This culture model provides a tool for dissecting the roles of the ECM and adipocytes in contributing to global adipose tissue metabolic phenotype and permits study of the role of the ECM in regulating adipose tissue homeostasis.

We describe a 3D human extracellular matrix-adipocyte in vitro culture system that permits dissection of the roles of the matrix and adipocytes in contributing to adipose tissue metabolic phenotype.

マトリックス細胞代謝クロストークを研究するためのヒト3D細胞外マトリックス-脂肪細胞培養モデル

The extracellular matrix (ECM) plays a central role in regulating tissue homeostasis, engaging in crosstalk with cells and regulating multiple aspects of ...

Controlled Strain of 3D Hydrogels under Live Microscopy Imaging

External forces are an important factor in tissue formation, development, and maintenance. The effects of these forces are often studied using specialized in vitro stretching methods. Various available systems use 2D substrate-based stretchers, while the accessibility of 3D techniques to strain soft hydrogels, is more restricted. Here, we describe a method that allows external stretching of soft hydrogels from their circumference, using an elastic silicone strip as the sample carrier. The stretching system utilized in this protocol is constructed from 3D-printed parts and low-cost electronics, making it simple and easy to replicate in other labs. The experimental process begins with polymerizing thick (&#62;100 &#956;m) soft fibrin hydrogels (Elastic Modulus of ~100 Pa) in a cut-out at the center of a silicone strip. Silicone-gel constructs are then attached to the printed-stretching device and placed on the confocal microscope stage. Under live microscopy the stretching device is activated, and the gels are imaged at various stretch magnitudes. Image processing is then used to quantify the resulting gel deformations, demonstrating relatively homogenous strains and fiber alignment throughout the gel&#8217;s 3D thickness (Z-axis). Advantages of this method include the ability to strain extremely soft hydrogels in 3D while executing in situ microscopy, and the freedom to manipulate the geometry and size of the sample according to the user&#8217;s needs. Additionally, with proper adaptation, this method can be used to stretch other types of hydrogels (e.g., collagen, polyacrylamide or polyethylene glycol) and can allow for analysis of cells and tissue response to external forces under more biomimetic 3D conditions.

The presented method involves uniaxial stretching of 3D soft hydrogels embedded in silicone rubber while allowing live confocal microscopy. Characterization of the external and internal hydrogel strains as well as fiber alignment are demonstrated. The device and protocol developed can assess the response of cells to various strain regimes.

ライブ顕微鏡イメージング下での3Dヒドロゲルの制御株

External forces are an important factor in tissue formation, development, and maintenance. The effects of these forces are often studied using specialized ...

Measuring 3D In-vivo Shoulder Kinematics using Biplanar Videoradiography

The shoulder is one of the human body's most complex joint systems, with motion occurring through the coordinated actions of four individual joints, multiple ligaments, and approximately 20 muscles. Unfortunately, shoulder pathologies (e.g., rotator cuff tears, joint dislocations, arthritis) are common, resulting in substantial pain, disability, and decreased quality of life. The specific etiology for many of these pathologic conditions is not fully understood, but it is generally accepted that shoulder pathology is often associated with altered joint motion. Unfortunately, measuring shoulder motion with the necessary level of accuracy to investigate motion-based hypotheses is not trivial. However, radiographic-based motion measurement techniques have provided the advancement necessary to investigate motion-based hypotheses and provide a mechanistic understanding of shoulder function. Thus, the purpose of this article is to describe the approaches for measuring shoulder motion using a custom biplanar videoradiography system. The specific objectives of this article are to describe the protocols to acquire biplanar videoradiographic images of the shoulder complex, acquire CT scans, develop 3D bone models, locate anatomical landmarks, track the position and orientation of the humerus, scapula, and torso from the biplanar radiographic images, and calculate the kinematic outcome measures. In addition, the article will describe special considerations unique to the shoulder when measuring joint kinematics using this approach.

Biplane videoradiography can quantify shoulder kinematics with a high degree of accuracy. The protocol described herein was specifically designed to track the scapula, humerus, and the ribs during planar humeral elevation, and outlines the procedures for data collection, processing, and analysis. Unique considerations for data collection are also described.

ビプラナービデオラジオグラフィーを用いた3Dインビボショルダーキネマティクスの測定

The shoulder is one of the human body's most complex joint systems, with motion occurring through the coordinated actions of four individual joints, ...

Cantilever Bending of Murine Femoral Necks

Fractures in the femoral neck are a common occurrence in individuals with osteoporosis. Many mouse models have been developed to assess disease states and therapies, with biomechanical testing as a primary outcome measure. However, traditional biomechanical testing focuses on torsion or bending tests applied to the midshaft of the long bones. This is not typically the site of high-risk fractures in osteoporotic individuals. Therefore, a biomechanical testing protocol was developed that tests the femoral necks of murine femurs in cantilever bending loading to replicate better the types of fractures experienced by osteoporosis patients. Since the biomechanical outcomes are highly dependent on the flexural loading direction relative to the femoral neck, 3D printed guides were created to maintain a femoral shaft at an angle of 20&#176; relative to the loading direction. The new protocol streamlined the testing by reducing variability in alignment (21.6&#176; &plusmn; 1.5&#176;, COV = 7.1%, n = 20) and improved reproducibility in the measured biomechanical outcomes (average COV = 26.7%). The new approach using the 3D printed guides for reliable specimen alignment improves rigor and reproducibility by reducing the measurement errors due to specimen misalignment, which should minimize sample sizes in mouse studies of osteoporosis.

The present protocol describes the development of a reproducible testing platform for murine femoral necks in a cantilever bending set-up. Custom 3D printed guides were used to consistently and rigidly fix the femurs in optimal alignment.

マウス大腿骨首のカンチレバー曲げ

Fractures in the femoral neck are a common occurrence in individuals with osteoporosis. Many mouse models have been developed to assess disease states and ...

A GMP-Compliant Procedure for the Generation of Gene-Modified T cells

The field of Adoptive Cell Therapy (ACT) has been revolutionized by the development of genetically modified cells, specifically Chimeric Antigen Receptor (CAR)-T cells. These modified cells have shown remarkable clinical responses in patients with hematologic malignancies. However, the high cost of producing these therapies and conducting extensive quality control assessments has limited their accessibility to a broader range of patients. To address this issue, many academic institutions are exploring the feasibility of in-house manufacturing of genetically modified cells, while adhering to guidelines set by national and international regulatory agencies.
Manufacturing genetically modified T cell products on a large scale presents several challenges, particularly in terms of the institution's production capabilities and the need to meet infusion quantity requirements. One major challenge involves producing large-scale viral vectors under Good Manufacturing Practice (GMP) guidelines, which is often outsourced to external companies. Additionally, simplifying the T cell transduction process can help minimize variability between production batches, reduce costs, and facilitate personnel training. In this study, we outline a streamlined process for lentiviral transduction of primary human T cells with a fluorescent marker as the gene of interest. The entire process adheres to GMP-compliant standards and is implemented within our academic institution.

This protocol outlines the process of transducing primary human T cells with a gene of interest, ensuring compatibility with Good Manufacturing Practice (GMP) standards.

遺伝子改変T細胞の作製のためのGMP準拠手順

The field of Adoptive Cell Therapy (ACT) has been revolutionized by the development of genetically modified cells, specifically Chimeric Antigen Receptor ...