この研究は、ボストンサイエンティフィック社のニューロモジュレーションによって賄われていた。

1。はじめに： 脊髄刺激、またはSCSは、臨床的に博士ノーマンシーリー、最初に慢性、難治性疼痛（シーリーら 、1967）の患者に対して救済を提供する試みで背側の列を介して刺激電極を移植するときに、1967年以降適用されている。 SCSは、脳の高次中枢（メルザック＆ウォールに痛みの信号の伝送に阻害し、または&quot;ゲートを閉じる&quot;ことができる、タッチと圧力の感覚を媒介する大規模な有髄求心性神経の活性化を仮説ゲートの理論、の臨床的な実装です。 、1965）。 SCSのための技術は、数十年にわたって改善されているより背の列を促進するため、より信頼性の刺激装置と進化しています。 これらの改善の鍵は、臨床的電気刺激に関連する脊髄の神経解剖学と神経生理学の増加理解してきました。この理解は、SCSの計算モデルによって進められてきた。ニューロンの計算モデルは、HodgkinとHuxleyの数学モデルが最初に（ホジキンとハクスリー、1952）に記載されて以来、神経刺激のための基本的なメカニズムを理解するために使用されています。神経活動は、細胞内の電流注入と、細胞外潜在的なフィールドとして印加される電界によって変調される。軸索の近くで細胞外電圧の変化が脱分極すると他の人が過分極する軸索の膜の一部の地域を引き起こす方法を定性的議論Ranck（Ranck、1975）。 SCSのための計算モデルは、当初コバーンとSin（コバーン、1980）によって開発されたものと大幅にStruijkとSCSの三次元場モデル（HolsheimerとStruijk、1988）のHolsheimerの開発から始まり、Holsheimerらが助長された。彼らの計算モデルは、脊髄後索線維（Struijk ら 、1992）のしきい値に関する解剖学的パラメータの効果を推定後根繊維（Struijk ら 、1993b）の励起の可能性のある位置を予測し、CSFの効果を分析臨床的検証と厚さ（Struijk ら、1993a。）（。彼ら 、1994; Holsheimer ら、1995a;。Holsheimerら、1994）。ルート繊維（Holsheimer らを介して脊髄後索線維の選択的刺激を好む、、、モデルは、コンタクトサイズと間隔（HolsheimerとWesselink、1997 HolsheimerとStruijk、1992）のための最適なパラメータを示唆し、刺激のリード設計の設計に大きく貢献。 1995b）。 2。方法： 数理モデルの定義有限要素数学（FEM）モデルは、低胸髄およびその周囲の環境から作成されました。 FEMモデルは、脊髄白と灰白質、脳脊髄液、硬膜、硬膜外の空間組織、脊椎骨、および2つの円筒マルチコンタクトのリード線で構成されていました。各リードには、ポリマーを（非導電性のドメインを、1mmの長さ）絶縁の1mmの長さで区切られた8つの円筒状の白金イリジウム接点（導電性のドメインの3mm長さおよび1.25 mmの直径）、から成っていた。リード線は、脊髄の正中線の両側に硬膜上に、背側に配置、および対称、1ミリメートルれた。モデルでは、連絡先や脊髄の背側表面（dCSF）との間の脳脊髄液の層の&quot;厚さ&quot;が3.2ミリメートルであることが指定されています。モデルの形状は、図1Aに示されていると電気抵抗率を表に与えられて私は、文学（Holsheimer、2002; Wesselink ら 、1999）から主に来る値。ボリュームは、近くに、図1Bに示すように電極が配置されている場所までの領域における高密度メッシュで、100万人以上のノードとメッシュ化された。 <img src="/files/ftp_upload/2443/2443fig1.jpg" alt="図1" /> 図1。脊髄とマルチコンタクトのリードのためのFEMのメッシュの描写。 （A）成分とモデルの構造。 （B）モデルのメッシュを - 唯一の高密度の一部が表示されます。メッシュは、変数ノード密度のセクションに分割なった：連絡先（≤300μm以下）の近くに、絶縁体、硬膜と脊髄（≤750μmの）、硬膜外の空間（≤3000μM）、および脊椎骨（≤5000μM）。 <img src="/files/ftp_upload/2443/2443table1.jpg" alt="表1" /> 表1抵抗FEMドメインの値（Holsheimer、2002;。Wesselinkら 、1999）。と変更は、（硬膜外の空間）の臨床データと一致する。 脊髄の形状（図2）関連文献の情報源からの機能の組み合わせを使用して作成されました。 。Struijk;。脊髄の断面は、（亀山ら 、1996亀山らから派生した、とStruijk らの後根（DR）軌道が採用されました。ら 、1993b）。背側カラム（DC）繊維がの規則的な格子（縦縞状方向と100um背腹方向の200um、図2Aを参照）に配置され、rostrocaudal方向に投影。それぞれのDRは、より小さい直径の二股&quot;娘&quot;繊維（図2B）に接続されている大径の&quot;母&quot;繊維としてモデル化されました。 <img src="/files/ftp_upload/2443/2443fig2.jpg" alt="図2" /> 図2。脊髄のモデルの構造。脊髄と脊髄後索線維の位置の（A）トランザクショナルビュー。 （B）背側根は、母の繊維と二股娘の繊維で構成されています。母の繊維の軌跡はStruijk 1993年からデジタル化した。脊髄とDR繊維の（C）三次元ビュー。 モデル調査リード線がモデル内に配置された後は、刺激の2つのタイプは2つのパラレル接点に電流を定義することによって実装されました。 A.：単一のソースシステムの場合は、電流を供給する3つの方法があった一番左の接触はすべての電流を持っています。B.それぞれが現在の50％を提供する2つの接点、C.右端の接触はすべての電流を供給します。我々は、これが臨床応用に真である可能性が低いものの2つの接点のインピーダンスは、等しいと仮定されていることをここで注意してください。 マルチソースのシステムの場合は、各接点は接点間の百分の一の増分電流の変化で制御可能、独自の電流源を持つように定義されました。言い換えると、全電流は2つの接点に配信された場合に、各接触等しい10ミリアンペアを流れる電流の和である限り、各連絡先に電流が合計の端数に指定されたマルチソースシステムで、10mAです。例えば、一番左のお問い合わせは右端の接触はその後3.2ミリアンペアを実現するという6.8ミリアンペアを配信することがあります。マルチソースのシステムの場合は、小数が現在の分割100はこの方法でプログラムされた。 各システムにより背側のカラム内の活性化の領域を計算するには、活性化関数の解析を行った。活性化関数は、細胞外刺激電流が与えられた電極と繊維の形状のために神経組織に適用される膜電位の変化の近似値です。活性化の領域は、活性化関数（または軸索に沿って電圧の単に2番目の差）が所定の閾値（例えば0.1mV/mm2）を超えて、モデル内の繊維の軌跡として定義されていました。刺激の中心点は、活性化の3次元領域の幾何学的な重心として定義して算出した。 刺激の振幅を決定するために、2つの接点は、単極の構成（モデルの境界線から同等の電流密度で供給される電流ソース）のカソード（2つの接点が50％および50％負電位）であることが指定されました。刺激の振幅は、繰り返し活性化（これは常に脊柱の繊維だった）が観察された最初の繊維まで増加した。この最初の活性化は、臨床の現場で患者による知覚障害の最初の知覚に相関すると仮定した。モデルでは、現在は、1.4 *（MA第一繊維を活性化する）に増加したと活性化の結果としての領域の重心を計算した。すべてのステアリングのステップ（100:0〜0:100）の重心が前のステップで決定した振幅を計算した。重心変化の平均分解能は、現在のステップで割ると重心位置の範囲であった。 3。結果： デュアルリード間mediolaterally刺激を操縦するときに、計算モデルは、連絡先ごとに独立した電流源を持つデバイスは、単一のソースシステム（100対3）より背の列への刺激のより多くの中心点をターゲットにできると予測している。その結果、刺激の中心点の調整の分解能は、マルチソースのシステムで30 UM、シングルソースのシステム（図3を参照）と比較して約50倍です。 <img src="/files/ftp_upload/2443/2443fig3.jpg" alt="図3" /> 図3計算モデルでは、次の予測が行われます。 A.デュアルリード構成：単極刺激とリードの間に2.0 mmの分離。 （2mmの鉛の分離と、平均で1 mmのステップサイズ）mediolaterally刺激をシフトするときにすべての連絡先の単一の共有電源を供給B.シングルソースのデバイスは、刺激の3つの中心点をターゲットにすることができます。 C：10％刻み（1％は0.02 mmのステップサイズでfractionalizing時に1％単位、または10の中央の点で現在のfractionalizing時連絡先ごとに専用の電源を持つデバイスは背側の列に横方向に100の中央のポイントをターゲットにすることができますステップと平均で10％ステップ）には0.2 mmである。

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著者は、ボストンサイエンティフィック社のニューロモジュレーションの従業員です。

高解像度と脊柱の中央の刺激の地域への能力は、患者の知覚異常、痛みのオーバーラップのよりよい最適化のためにできる可能性があります。つまり、特定の患者に、ある、背の列の活性化の領域は、痛みの領域のカバレッジを最大限に集中することができる一方、最小限の副作用（モーターや自律神経の望ましくない場所に感覚異常を生成または作成することが望ましくない繊維の刺激に起因する効果）。

<ul><li> NEURON（ <a href="http://www.neuron.yale.edu">http://www.neuron.yale.edu</a> ） </li><li> ANSYS（キャノンズバーグ、ペンシルバニア州、 <a href="http://www.ansys.com">http://www.ansys.com</a> ） </li><li> MathWorks社のMATLAB（ナティック、マサチューセッツ、 <a href="http://www.mathworks.com">http://www.mathworks.com</a> ） </li></ul>

dorsal column steerability with dual parallel leads using dedicated power sources:  a computational model

の脊髄刺激（SCS）、痛みを伴う身体領域にわたって刺激誘発性異常感覚の一致は、治療効果のための必要条件である。患者の痛みのパターンは一意であることができるので、一般的な刺激の構成では、背側硬膜外腔に平行に2本のリード線の配置です。この構築物は、より痛みの感覚異常のオーバーラップを達成するために脊柱以上mediolaterally現在のステアリング刺激で柔軟性を提供します。正確な繊維径分布を持つ数学的モデルを使用して、我々は、デュアルパラレルの能力を研究したデュアル並列で隣接コンタクト間に刺激を操縦するためにリードを使用してつながる（1）単一のソースシステムを、そして（2）マルチソースシステム、各連絡先の電流源を捧げた。硬膜外に好位置デュアルパラレル（2 mmの分離）経皮的リード線の付いた低胸髄の容積導体モデルが最初に作成され、電界がANSYS、有限要素モデリングツールを用いて算出した。 10μMの繊維の活性化関数は、脊柱の神経線維で絞輪のノードに沿って細胞外電位の第二の違いとして計算した。アクティベーション（VOA）とVOAの中心点の体積は、活性化関数の所定のしきい値を用いて計算した。モデルは、単一のソース対デュアル8接触刺激のリード線上に専用の電源システムとフィールドのステアリングの結果を比較した。モデルは、マルチソースシステムは、単一のソースシステムよりも背の列に刺激のより多くの中心点をターゲットにすることができます（100対3）と中外側のステアリングの平均ステアリングステップは、マルチソースシステム対1 mmの0.02ミリメートルであることが予測単一のソースシステムのための、50倍に改善。高解像度と脊柱の中央の刺激の地域への能力は、患者の知覚異常、痛みのオーバーラップのよりよい最適化のためにできる可能性があります。

Watch this Scientific Journal Video about Dorsal Column Steerability with Dual Parallel Leads using Dedicated Power Sources:  A Computational Model at JoVE.com

Dorsal Column Steerability with Dual Parallel Leads using Dedicated Power Sources:  A Computational Model

脊髄刺激の数学的モデルを使用して、我々は（連絡先ごとに独立した電源を持つマルチソースシステムは背列に刺激のより多くの中心点（100対3）をターゲットにできることがわかったと50倍以上のフィールドステアリング分解能を持っています単一ソースのシステムより0.02ミリメートル対1ミリメートル）。

専用電源を使用してデュアルパラレルのリードで脊柱の操縦：計算モデル

In spinal cord stimulation (SCS), concordance of stimulation-induced paresthesia over painful body regions is a necessary condition for therapeutic ...

dorsal-column-steerability-with-dual-parallel-leads-using-dedicated

Research

JoVE Journal

Medicine

11.7K ビュー.  Neuromodulation. 脊髄刺激の数学的モデルを使用して、我々は（連絡先ごとに独立した電源を持つマルチソースシステムは背列に刺激のより多くの中心点（100対3）をターゲットにできることがわかったと50倍以上のフィールドステアリング分解能を持っています単一ソースのシステムより0.02ミリメートル対1ミリメートル）。

ビデオ: Dorsal Column Steerability with Dual Parallel Leads using Dedicated Power Sources:  A Computational Model

A Novel Capsulorhexis Technique Using Shearing Forces with Cystotome

Purpose:
To demonstrate a capsulorhexis technique using predominantly shearing forces with a cystotome on a virtual reality simulator and on a human eye.
Method:
Our technique involves creating the initial anterior capsular tear with a cystotome to raise a flap. The flap left unfolded on the lens surface. The cystotome tip is tilted horizontally and is engaged on the flap near the leading edge of the tear. The cystotome is moved in a circular fashion to direct the vector forces. The loose flap is constantly swept towards the centre so that it does not obscure the view on the tearing edge.
Results:
Our technique has the advantage of reducing corneal wound distortion and subsequent anterior chamber collapse. The capsulorhexis flap is moved away from the tear leading edge allowing better visualisation of the direction of tear. This technique offers superior control of the capsulorhexis by allowing the surgeon to change the direction of the tear to achieve the desired capsulorhexis size.
Conclusions:
The EYESI Surgical Simulator is a realistic training platform for surgeons to practice complex capsulorhexis techniques. The shearing forces technique is a suitable alternative and in some cases a far better technique in achieving the desired capsulorhexis.

This video demonstrates a novel capsulorhexis technique in modern cataract surgery. Capsulorhexis is the most difficult and important part of phacoemulsification surgery.

胆嚢切開刀で剪断力を用いた新規Capsulorhexisテクニック

Purpose:
To demonstrate a capsulorhexis technique using predominantly shearing forces with a cystotome on a virtual reality simulator and on a human eye....

医学

In vivo Dual Substrate Bioluminescent Imaging

Our understanding of how and when breast cancer cells transit from established primary tumors to metastatic sites has increased at an exceptional rate since the advent of in vivo bioluminescent imaging technologies 1-3. Indeed, the ability to locate and quantify tumor growth longitudinally in a single cohort of animals to completion of the study as opposed to sacrificing individual groups of animals at specific assay times has revolutionized how researchers investigate breast cancer metastasis. Unfortunately, current methodologies preclude the real-time assessment of critical changes that transpire in cell signaling systems as breast cancer cells (i) evolve within primary tumors, (ii) disseminate throughout the body, and (iii) reinitiate proliferative programs at sites of a metastatic lesion. However, recent advancements in bioluminescent imaging now make it possible to simultaneously quantify specific spatiotemporal changes in gene expression as a function of tumor development and metastatic progression via the use of dual substrate luminescence reactions. To do so, researchers take advantage for two light-producing luciferase enzymes isolated from the firefly (Photinus pyralis) and sea pansy (Renilla reniformis), both of which react to mutually exclusive substrates that previously facilitated their wide-spread use in in vitro cell-based reporter gene assays 4. Here we demonstrate the in vivo utility of these two enzymes such that one luminescence reaction specifically marks the size and location of a developing tumor, while the second luminescent reaction serves as a means to visualize the activation status of specific signaling systems during distinct stages of tumor and metastasis development. Thus, the objectives of this study are two-fold. First, we will describe the steps necessary to construct dual bioluminescent reporter cell lines, as well as those needed to facilitate their use in visualizing the spatiotemporal regulation of gene expression during specific steps of the metastatic cascade. Using the 4T1 model of breast cancer metastasis, we show that the in vivo activity of a synthetic Smad Binding Element (SBE) promoter was decreased dramatically in pulmonary metastasis as compared to that measured in the primary tumor 4-6. Recently, breast cancer metastasis was shown to be regulated by changes within the primary tumor microenvironment and reactive stroma, including those occurring in fibroblasts and infiltrating immune cells 7-9. Thus, our second objective will be to demonstrate the utility of dual bioluminescent techniques in monitoring the growth and localization of two unique cell populations harbored within a single animal during breast cancer growth and metastasis.

In vivo Dual Substrate Bioluminescent Imaging

Herein we describe the methods to construct, visualize, and quantify the bioluminescent reactions of both firefly and renilla luciferase enzymes expressed in metastatic breast cancer cells during their growth and metastasis in vivo.

生体デュアル基質生物発光イメージングにおける

Our understanding of how and when breast cancer cells transit from established primary tumors to metastatic sites has increased at an exceptional rate ...

Deep Neuromuscular Blockade Leads to a Larger Intraabdominal Volume During Laparoscopy

Shoulder pain is a commonly reported symptom following laparoscopic procedures such as myomectomy or hysterectomy, and recent studies have shown that lowering the insufflation pressure during surgery may reduce the risk of post-operative pain. In this pilot study, a method is presented for measuring the intra-abdominal space available to the surgeon during laproscopy, in order to examine whether the relaxation produced by deep neuromuscular blockade can increase the working surgical space sufficiently to permit a reduction in the CO2 insufflation pressure. Using the laproscopic grasper, the distance from the promontory to the skin is measured at two different insufflation pressures: 8 mm Hg and 12 mm Hg. After the initial measurements, a neuromuscular blocking agent (rocuronium) is administered to the patient and the intra-abdominal volume is measured again. Pilot data collected from 15 patients shows that the intra-abdominal space at 8 mm Hg with blockade is comparable to the intra-abdominal space measured at 12 mm Hg without blockade. The impact of neuromuscular blockade was not correlated with patient height, weight, BMI, and age. Thus, using neuromuscular blockade to maintain a steady volume while reducing insufflation pressure may produce improved patient outcomes.

This article presents a method for measuring the working abdominal volume during laproscopic myomectomy using the surgical grasper, and applies this technique to obtain pilot data on whether deep neuromuscular blockade (NMB) can enable the use of lower insufflation pressure. Reduced insufflation pressure during laproscopic surgery has been shown to reduce post-operative pain, and thus the use of NMB during surgery may enable improved patient outcomes.

深い神経筋遮断は腹腔鏡の間大きな腹腔内容積につながる

Shoulder pain is a commonly reported symptom following laparoscopic procedures such as myomectomy or hysterectomy, and recent studies have shown that ...

Ischemic Tissue Injury in the Dorsal Skinfold Chamber of the Mouse: A Skin Flap Model to Investigate Acute Persistent Ischemia

Despite profound expertise and advanced surgical techniques, ischemia-induced complications ranging from wound breakdown to extensive tissue necrosis are still occurring, particularly in reconstructive flap surgery. Multiple experimental flap models have been developed to analyze underlying causes and mechanisms and to investigate treatment strategies to prevent ischemic complications. The limiting factor of most models is the lacking possibility to directly and repetitively visualize microvascular architecture and hemodynamics. The goal of the protocol was to present a well-established mouse model affiliating these before mentioned lacking elements. Harder et al. have developed a model of a musculocutaneous flap with a random perfusion pattern that undergoes acute persistent ischemia and results in ~50% necrosis after 10 days if kept untreated. With the aid of intravital epi-fluorescence microscopy, this chamber model allows repetitive visualization of morphology and hemodynamics in different regions of interest over time. Associated processes such as apoptosis, inflammation, microvascular leakage and angiogenesis can be investigated and correlated to immunohistochemical and molecular protein assays. To date, the model has proven feasibility and reproducibility in several published experimental studies investigating the effect of pre-, peri- and postconditioning of ischemically challenged tissue.

The window of the murine dorsal skinfold chamber presented visualizes a zone of acute persistent ischemia of a musculocutaneous flap. Intravital epi-fluorescence microscopy permits for direct and repetitive assessment of the microvasculature and quantification of hemodynamics. Morphologic and hemodynamic results can further be correlated with histological and molecular analyses.

マウスの背部皮脂商工における虚血性組織損傷：皮膚弁モデル急性永続虚血を調査する

Despite profound expertise and advanced surgical techniques, ischemia-induced complications ranging from wound breakdown to extensive tissue necrosis are ...

Isometric Contractility Measurement of the Mouse Mesenteric Artery Using Wire Myography

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and drugs. It is widely used in many studies on the physiological functions of vascular smooth muscle, the pathogenesis of vascular diseases such as hypertension, and the development of smooth muscle relaxant drugs. The mouse is a widely used model animal with a large pool of disease models and genetically modified strains. We introduced this method to measure the isometric contraction of mouse mesenteric artery in detail. A 1.4-mm segment of mouse mesenteric resistance artery was isolated and mounted on a myograph chamber by passing two steel wires through its lumen. After equilibration and normalization steps, the vessel segment was potentiated by a high-K+ solution twice prior to the contraction assay. As an example of the application of this method in drug development, we measured the relaxant effect of a novel natural substance, neoliensinine, isolated from a Chinese herb, embryos of the lotus seed (Nelumbo nucifera Gaertn.) on mouse mesenteric arteries. The vessel segments mounted on the myograph chamber were stimulated with a high-K+ solution. When the force tension reached a stable sustained phase, cumulative doses of neoliensinine were added to the chamber. We found that neoliensinine had a dose-dependent relaxant effect on smooth muscle contraction, thus suggesting that it bears potential activity against hypertension. In addition, as the vessel segment can survive at least 4 hours after mounting and maintain contractility induced by the high-K+ solution for many times, we suggest that the wire myograph system may be used for the time-consuming process of drug screening.

The wire myograph technique is used to investigate vascular smooth muscle functions and screen new drugs. We report a detailed protocol for measuring the isometric contractility of the mouse mesenteric artery and for screening new relaxants of vascular smooth muscle.

ワイヤー図法を使用してマウスの腸間膜動脈の等尺性収縮力測定

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and ...

Murine Model of Central Venous Stenosis using Aortocaval Fistula with an Outflow Stenosis

Central venous stenosis is an important entity contributing to arteriovenous fistula (AVF) failure. A murine AVF model was modified to create a partial ligation of the inferior vena cava (IVC) in the outflow of the fistula, mimicking central venous stenosis. Technical aspects of this model are introduced. The aorta and IVC are exposed, following an abdominal incision. The infra-renal aorta and IVC are dissected for proximal clamping, and the distal aorta is exposed for puncture. The IVC at the midpoint between the left renal vein and the aortic bifurcation is carefully dissected to place an 8-0 suture beneath the IVC. After clamping the aorta and IVC, an AVF is created by puncturing the infra-renal aorta through both walls into the IVC with a 25 G needle, followed by ligating a 22 G intra-venous (IV) catheter and IVC together. The catheter is then removed, creating a reproducible venous stenosis without occlusion. The aorta and IVC are unclamped after confirming primary hemostasis. This novel model of central vein stenosis is easy to perform, reproducible, and will facilitate studies on AVF failure.

An aortocaval fistula was created by puncturing the murine infra-renal aorta through both walls into the inferior vena cava and was followed by creation of a stenosis in its outflow via partial ligation of the inferior vena cava. This reproducible model can be used to study central venous stenosis.

流出狭窄を伴う大軌道瘻を用した中枢静脈狭窄のマウスモデル

Central venous stenosis is an important entity contributing to arteriovenous fistula (AVF) failure. A murine AVF model was modified to create a partial ...

A Porcine Corneal Endothelial Organ Culture Model Using Split Corneal Buttons

Experimental research on corneal endothelial cells is associated with several difficulties. Human donor corneas are scarce and rarely available for experimental investigations as they are normally needed for transplantation. Endothelial cell cultures often do not translate well to in vivo situations. Due to the biostructural characteristics of non-human corneas, stromal swelling during cultivation induces substantial corneal endothelial cell loss, which makes it difficult to perform cultivation for an extended period of time. Deswelling agents such as dextran are used to counteract this response. However, they also cause significant endothelial cell loss. Therefore, an ex vivo organ culture model not requiring deswelling agents was established. Pig eyes from a local slaughterhouse were used to prepare split corneal buttons. After partial corneal trephination, the outer layers of the cornea (epithelium, bowman layer, parts of the stroma) were removed. This significantly reduces corneal endothelial cell loss induced by massive stromal swelling and Descemet&#39;s membrane folding throughout longer cultivation periods and improves general preservation of the endothelial cell layer. Subsequent complete corneal trephination was followed by the removal of the split corneal button from the remaining eye bulb and cultivation. Endothelial cell density was assessed at follow-up times of up to 15 days after preparation (i.e., days 1, 8, 15) using light microscopy. The preparation technique used allows a better preservation of the endothelial cell layer enabled by less stromal tissue swelling, which results in slow and linear decline rates in split corneal buttons comparable to human donor corneas. As this standardized organo-typically cultivated research model for the first time allows a stable cultivation for at least two weeks, it is a valuable alternative to human donor corneas for future investigations of various external factors with regards to their effects on the corneal endothelium.

Here, a step-by-step protocol for the preparation and cultivation of porcine split corneal buttons is presented. As this organo-typically cultivated organ culture model shows cell death rates within 15 days, comparable to human donor corneas, it represents the first model allowing long-term cultivation of non-human corneas without adding toxic dextran.

分割角膜ボタンを用いてのブタ角膜内皮器培養モデル

Experimental research on corneal endothelial cells is associated with several difficulties. Human donor corneas are scarce and rarely available for ...

In Vivo Quantification of Hip Arthrokinematics during Dynamic Weight-bearing Activities using Dual Fluoroscopy

Several hip pathologies have been attributed to abnormal morphology with an underlying assumption of aberrant biomechanics. However, structure-function relationships at the joint level remain challenging to quantify due to difficulties in accurately measuring dynamic joint motion. The soft tissue artifact errors inherent in optical skin marker motion capture are exacerbated by the depth of the hip joint within the body and the large mass of soft tissue surrounding the joint. Thus, the complex relationship between bone shape and hip joint kinematics is more difficult to study accurately than in other joints. Herein, a protocol incorporating computed tomography (CT) arthrography, three-dimensional (3D) reconstruction of volumetric images, dual fluoroscopy, and optical motion capture to accurately measure the dynamic motion of the hip joint is presented. The technical and clinical studies that have applied dual fluoroscopy to study form-function relationships of the hip using this protocol are summarized, and the specific steps and future considerations for data acquisition, processing, and analysis are described.

In Vivo Quantification of Hip Arthrokinematics during Dynamic Weight-bearing Activities using Dual Fluoroscopy

Dual fluoroscopy accurately captures in vivo dynamic motion of human joints, which can be visualized relative to reconstructed anatomy (e.g., arthrokinematics). Herein, a detailed protocol to quantify hip arthrokinematics during weight-bearing activities of daily living is presented, including the integration of dual fluoroscopy with traditional skin marker motion capture.

イン・ヴィヴォ 二重蛍光法による動的体重負荷活動における股関節運動学の定量化

Several hip pathologies have been attributed to abnormal morphology with an underlying assumption of aberrant biomechanics. However, structure-function ...

Modified Posterior Vertebral Column Resection for Patients with Thoracolumbar Kyphotic Deformity

Old compression vertebrae fracture or congenital kyphoscoliosis with abnormal vertebral body development and other diseases that invade the spine may cause severe thoracolumbar kyphotic deformity, often accompanied by intractable low back pain or compression of the spinal cord, leading to severe neurological symptoms or even paralysis. If conservative treatment cannot relieve the symptoms or correct the deformities, surgical treatment is usually needed. For severe kyphotic deformity, reconstruction of the physiological curvature and rigid fixation determine the prognosis of the patients. Osteotomy and orthopedics are the standard procedure for deformities with severe compression of the front and middle column, but the trauma to the patients is high, with a long operation time and massive blood loss. To avoid these disadvantages, we have developed a modified technique to remove the diseased vertebra unilaterally. In this technique, we use a modified trephine to resect the vertebral columns like in the pedicle screw technique by adding a locking instrument that can restrict the trephine to lower the risk of osteotomy and shorten the surgery time and blood loss.

We describe a modified technique for resecting the posterior vertebral column unilaterally based on a modified trephine for patients with thoracolumbar kyphotic deformity.

胸腰椎後弯変形症に対する修正後脊柱切除術

Old compression vertebrae fracture or congenital kyphoscoliosis with abnormal vertebral body development and other diseases that invade the spine may ...

Rat DRG 圧縮モデルのための標準化された Tuina プロトコル

Analgesic Effect of Tuina on Rat Models with Compression of the Dorsal Root Ganglion Pain

Neuropathic pain is a prevalent condition that affects 6.9%-10% of the population and results from nerve damage due to various etiologies, such as lumbar disc herniation, spinal canal stenosis, and intervertebral foramen stenosis. Although Tuina, a traditional Chinese manual therapy, has shown analgesic effects in clinical practice for the treatment of neuropathic pain, its underlying neurobiological mechanisms remain unclear. Animal models are essential for elucidating the basic principles of Tuina. In this study, we propose a standardized Tuina protocol for rats with compression of the dorsal root ganglion (DRG), which involves inducing DRG compression by inserting a stainless steel rod into the intervertebral foramen, performing Tuina manipulation with specific parameters of location, intensity, and frequency in a controlled environment, and assessing the behavioral and histopathological outcomes of Tuina treatment. This article also discusses the potential clinical implications and limitations of the study and suggests directions for future research on Tuina.

著者スポットライト:背根神経節の痛みの圧縮を伴うラットモデルに対するTuinaの鎮痛効果  

This article presents a manipulation for treating chronic compression of the dorsal root ganglion in rats using Tuina therapy, along with a method for evaluating its effectiveness based on pain behavior and histopathological results.

背根神経節痛の圧迫を伴うラットモデルに対する推拿の鎮痛効果

Neuropathic pain is a prevalent condition that affects 6.9%-10% of the population and results from nerve damage due to various etiologies, such as lumbar ...