作者希望感谢瓦莱丽施罗德对这项工作的技术方面的帮助。与这个模型的发展相关的工作由库克生物技术, Inc. (西拉斐特, 在美国) 支持。

在本议定书中使用动物是由圣母大学机构动物照料和使用委员会批准的, 遵循所有的管理要求和准则, 并在由国际实验室动物保育 (AAALAC) 评估和认可协会. 
 1. 选择动物 <ol> <li> 从有信誉的供应商或育种群体中获得无病原体大鼠. 
	注: 通常情况下, 设施兽医或经理可以指示调查员到适当的来源。大约 250 g 体重的老鼠适合这个做法. </li>
	<li> 在手术前的一天, 检查动物以确保它们在临床上是健康的。在这方面, 权衡动物和评估身体状况;注意呼吸的任何异常, 任何开放性的伤口或肿块的存在, 以及动物的一般活动水平。注意手术记录中的任何异常, 并将此类观察视为潜在的排除标准. </li>
</ol> 2。无菌外科动物的麻醉和制备 <ol> <li> 用于镇痛, 管理 1.1-1.2 毫克/千克的持续释放丁丙诺啡, 皮下注射到鼠 2 #160; 手术前. 和 #160; 眼膏对眼睛的应用和管理2毫升温热的无菌生理生理盐水皮下. </li>
	<li> 麻醉鼠腹腔剂量氯胺酮盐酸盐 (90 毫克/千克) 和嗪 (10 毫克/千克)。用少量的眼部润滑剂来预防角膜 dessication。一旦动物和 #8217 的呼吸是稳定的, 不再有任何反应, 一个坚定的脚趾捏, 老鼠已经达到了麻醉水平足够的手术。可接受的麻醉水平可以进一步证实, 存在深, 定期呼吸和正常的眼睛颜色 ( 与 苍白, 这可能意味着不充分的心血管灌注). </li>
	<li> 从耻骨到胸骨, 从侧边到 ventrum, 用商业快船队刮腹腹部。通过向区域应用湿纸巾来去除修剪过的毛发. </li>
	<li> 用碘防腐剂擦洗剃光区域, 然后用70% 的乙醇擦拭。应用手术窗帘, 使切口的窗口可以与潜在的污染隔离. </li>
	<li> 不育的手术礼服, 口罩, 和头发的帽子。用肥皂和不育的外科手套彻底清洗和擦洗双手. </li>
</ol> 3。腹腹疝的制作与修复 <ol> <li> 手术前, 用高压釜消毒手术器械. </li>
	<li> 使用手术刀, 使大约 3-4 厘米垂直切口沿腹中线向下到腹部肌组织的水平。用镊子轻轻提起腹壁, 并通过式阿尔巴创建一个小开口。为了保护部下的内脏, 插入一个钳通过孔和进入腹腔, 作为一个保护指南, 当肌肉壁被切开创造一个大约 2 cm x 2 cm 完全厚度瑕疵, 切开大约 1 cm 侧向从每边式阿尔巴切口两端的中线. </li>
	<li> 放置一个预 2 cm x 2 厘米的机械桥接材料, 4 层 SIS 在这种情况下 ( 图 1 ), 在缺陷. 
	注: 另一种方法是, 可以使用一个衬底的方式, 其中的一部分材料被放置到腹腔, 以弥补缺陷从内部方面. </li>
	<li> 将桥接材料的四角缝合到腹壁肌肉, 使用4-0 丝或尼龙在一个简单的间断缝合模式. 
	注: 使用吸收缝合可方便地识别在收获与可吸收缝合材料上植入的材料. </li>
	<li> 确保材料的每个边缘都与三附加的缝合线相等。检查整个圆周边缘, 以确保不存在可能允许通过腹壁的内脏通过的重大缺口;而且, 如果存在此类缺口, 请放置额外的缝合线以进一步确保边距. </li>
	<li> 用4-0 可吸收缝合线闭合皮下组织, 以一种简单的间断模式。缝合皮肤与手术的主食, 虽然缝线应用在一个简单的中断模式也可以使用. </li>
	<li> 不要让动物无人看管, 直到它恢复了足够的意识, 重新夺回胸骨卧床; 并且, 在完全从麻醉中恢复之前, 不要将已经接受过手术的动物归还给其他动物。在此期间, 保持动物在一个温暖的地区, 以防止体温过低. </li>
	<li> 每天检查已经历此过程的动物, 以确保完全恢复和正常愈合。去除皮钉与主食卸妆 7-10 天后手术. </li>
</ol> 4。植入材料的收获 <ol> <li> 符合研究的需要, 安乐, 二氧化碳过量在室内填充率为10到 30%, 动物在预定时间, 通常在手术后 21-28 天. </li>
	<li> 使用标准的尸检工具, 打开皮肤和腹壁, 并暴露种植体的面积. 
	注意: 如果使用吸收缝合来保护植入物, 那么材料可以通过原始的缝合线 ( 图 2 ) 进行识别. </li>
	<li> 观察任何大体的病理观察, 包括任何不良反应 (如: , 伤口裂开, 脓肿, 液化, 血肿), 粘连程度和对部下脏器的坚韧性. </li>
	<li> 通过切割包括植入物在内的一组广泛的组织来移除植入物部位。将样品放在固定剂中, 如10% 中性缓冲福尔马林, 准备进行组织学检查和鉴定. </li>
</ol>

<ol>
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其中一个作者 (CJ) 是由库克生物技术, Inc., 制造商的医疗级 SIS。

腹腹疝修补术的材料非常有趣, 特别是那些提供了一个初步的机械桥, 然后能够纳入宿主组织。在这方面, 研究了多种材料, 包括 SIS、猪脱细胞真皮基质和猪心包。6,7这些材料代表这些组织的胞外基质, 并充当细胞可以迁移和增殖的支架, 从而促进组织的整合。
疝修补材料的评价需要一种易于处理且具有完整愈合能力的动物模型。大?...

腹壁疝是一个常见的临床问题, 可能发生的原因是先天性缺损, 外伤, 或关闭手术伤口累及腹壁。修复通常涉及使用植入物来加强腹壁, 以减少复发率, 在治疗的患者与植入物相比, 那些在腹壁是简单地封闭与缝合。1
手术疝修补往往需要机械架桥的缺陷与植入材料。在这方面, 合成和天然材料都被用于疝气修补。许多合成材料通常是吸收, 包括聚丙烯, 聚对苯二甲酸乙二醇酯聚酯, 和扩大聚四氟乙烯, 而其他合成植入物结合之一的吸收材料与可吸收聚合物如 polygalactine。1相比之下, 天然材料植入物通常来源于动物或人类尸体来源。用于疝修补的天然材料通常富含胶原蛋白, 并作为长和宿主组织整合的支架。
开发和优化腹腹疝修补新材料的愿望需要一个合适的动物模型来评估候选材料。研究已在各种物种进行, 包括绵羊,2猪,3兔,4大鼠,5,6,7,8和狗。9使用大鼠进行此类研究的优势在于, 它们提供了一种易于处理的模型, 可用于各种自交系, 从而控制遗传变异。此外, 与上述其他物种相比, 小鼠整体体表面积较小, 因此可以对可能具有实验性质的材料进行评估, 因此不太丰富。 此外, 与其他种类的老鼠相比, 降低了与其他物种相关的成本, 可以相对提高筛选候选材料的能力, 以便用于腹腹疝的修复。 对材料的考虑通常包括由外科医生的易于处理, 强度, 纳入宿主组织的能力, 生物相容性和抵抗感染。
作为一个例子, 猪小肠黏膜下层 (SIS) 是一种天然生物材料, 已被用于广泛的组织修复适应症, 包括修复腹腹部, 腹股沟, 和膈疝。10,11,12 SIS 迅速并入宿主组织中, 并被发现对感染具有普遍的抵抗力, 因此该材料在受污染的领域具有特殊用途。13,14在大鼠模型中, SIS 表现出了易于处理、拉伸强度和单轴拉伸破坏试验所确定的良好抗拉强度, 并在胶原沉积和新生血管方面促进组织长。6,7
准确的手术桥接缺陷是评估候选修复材料时生产模型的一个基本特征。动物必须充分麻醉和无菌技术严格遵循。此外, 一个标准尺寸的腹壁缺陷, 必须仔细地创建, 然后桥接的方式, 足以保证材料的缺陷的边缘。8本协议提供了一种标准方法, 用于手术创建和修复腹腹疝, 以 SIS 为例, 在大鼠中架桥材料。

<table border="0" cellpadding="0" cellspacing="0" width="573">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Isoflurane (Isoflo)</td>
			<td style="width:71px;">Henry Schine Animal Health</td>
			<td align="right" style="width:119px;">17579</td>
			<td style="width:167px;">gas anesthetic</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Optixcare Eye Lubricant</td>
			<td style="width:71px;">Henry Schine Animal Health</td>
			<td style="width:119px;">OPX4240</td>
			<td>Ocular lubricant</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Oster clippers</td>
			<td style="width:71px;">Henry Schine Animal Health</td>
			<td align="right" style="width:119px;">6092</td>
			<td>hair clippers</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Betadine surgical scrub</td>
			<td style="width:71px;">Henry Schine Animal Health</td>
			<td align="right" style="width:119px;">1618</td>
			<td>antiseptic iodophor</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Sterile scalpel</td>
			<td style="width:71px;">Henry Schine Animal Health</td>
			<td align="right" style="width:119px;">329</td>
			<td>#10 scalpel</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">9&#34; x 12&#34; disposable surgical drape</td>
			<td style="width:71px;">Braintree Scientific, Inc.</td>
			<td style="width:119px;">SP-RPS</td>
			<td>Surgical drape</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">4-0 nylon suture</td>
			<td style="width:71px;">Braintree Scientific, Inc.</td>
			<td style="width:119px;">SUT 812</td>
			<td>Suture material</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">4-0 Absorbable Suture</td>
			<td style="width:71px;">Henry Schine Animal Health</td>
			<td align="right" style="width:119px;">29242</td>
			<td>Synthetic absorbable suture</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">9 mm Autoclips and applier</td>
			<td style="width:71px;">Braintree Scientific, Inc.</td>
			<td style="width:119px;">ACS KIT</td>
			<td>Surgical staples for closure of skin incision</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Torbugesic/analgesic</td>
			<td style="width:71px;">Henry Schine Animal Health</td>
			<td align="right" style="width:119px;">12084</td>
			<td>Butorphanol tartarate for post-operative analgesia</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Small intestinal submucosa (SIS)</td>
			<td style="width:71px;">Cook Biotech, Inc.</td>
			<td style="width:119px;"></td>
			<td>Implant material for bridging experimental abdominal wall defect</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Rats</td>
			<td style="width:71px;">Harlan, Inc.</td>
			<td style="width:119px;">Sprague Dawley</td>
			<td>Animal for hernia modeling</td>
		</tr>
	</tbody>
</table>

use of a rat model to study ventral abdominal hernia repair

腹腹疝是一个相对常见的临床情况, 有时需要疝 (手术修复)。腹腹疝的修复通常需要植入一种材料, 作为横跨腹壁缺损的机械桥。生物材料, 如猪小肠黏膜下层 (SIS), 也充当细胞生长到植入体的晶格, 并能自然地融入宿主组织。这种修复材料的开发得益于动物模型的使用, 其中实验性的腹壁缺损很容易被创造出来, 并且可以以可重现的方式修复。本文所提供的方法描述了大鼠腹腹疝的手术制作和修复。当 SIS 用于修复实验性腹腹疝时, 该模型在植入后28天内迅速纳入宿主组织。组织学上, 其植入的材料纳入宿主组织的特点是一个强大的纤维反应。未来的改良和应用大鼠腹疝模型可能会涉及糖尿病和/或肥胖动物, 作为一种手段, 更密切模仿人类的共同疾病。

在植入后28天, SIS 通常会将良好的合并到宿主组织中 (图 2)。在大多数情况下, 有残余的 SIS 明显, 虽然必须经常探索组织, 以确定植入的材料。组织学分析证实了大体的病理观察, 说明良好的组织合并主要纤维组织和很少残留 SIS (图 3)。这些结果证明了大鼠腹腹疝模型的实用性。大鼠易于获得和维持, 一般在手术后迅速恢复。在植入的生物材料中的?...

Watch this Scientific Journal Video about Use of a Rat Model to Study Ventral Abdominal Hernia Repair at JoVE.com

Use of a Rat Model to Study Ventral Abdominal Hernia Repair

这篇手稿描述了与腹壁缺损 (疝气) 的创建和修复相关的方法。这种模型可以用来研究修复策略, 如那些使用植入材料。本论文以猪小肠黏膜下层为例, 对实验性疝修补术进行了探讨。

大鼠模型在腹腹疝修补术中的应用研究

Ventral abdominal hernia is a relatively common clinical condition that sometimes requires herniorraphy (surgical repair). The repair of ventral abdominal ...

use-of-a-rat-model-to-study-ventral-abdominal-hernia-repair

Research

JoVE Journal

Bioengineering

9.1K 次观看.  University of Minnesota. 这篇手稿描述了与腹壁缺损 (疝气) 的创建和修复相关的方法。这种模型可以用来研究修复策略, 如那些使用植入材料。本论文以猪小肠黏膜下层为例, 对实验性疝修补术进行了探讨。

视频: Use of a Rat Model to Study Ventral Abdominal Hernia Repair

The Three-Dimensional Human Skin Reconstruct Model: a Tool to Study Normal  Skin and Melanoma Progression

Most in vitro studies in experimental skin biology have been done in 2-dimensional (2D) monocultures, while accumulating evidence suggests that cells behave differently when they are grown within a 3D extra-cellular matrix and also interact with other cells (1-5). Mouse models have been broadly utilized to study tissue morphogenesis in vivo. However mouse and human skin have significant differences in cellular architecture and physiology, which makes it difficult to extrapolate mouse studies to humans. Since melanocytes in mouse skin are mostly localized in hair follicles, they have distinct biological properties from those of humans, which locate primarily at the basal layer of the epidermis. The recent development of 3D human skin reconstruct models has enabled the field to investigate cell-matrix and cell-cell interactions between different cell types. The reconstructs consist of a "dermis" with fibroblasts embedded in a collagen I matrix, an "epidermis", which is comprised of stratified, differentiated keratinocytes and a functional basement membrane, which separates epidermis from dermis. Collagen provides scaffolding, nutrient delivery, and potential for cell-to-cell interaction. The 3D skin models incorporating melanocytic cells recapitulate natural features of melanocyte homeostasis and melanoma progression in human skin. As in vivo, melanocytes in reconstructed skin are localized at the basement membrane interspersed with basal layer keratinocytes. Melanoma cells exhibit the same characteristics reflecting the original tumor stage (RGP, VGP and metastatic melanoma cells) in vivo. Recently, dermal stem cells have been identified in the human dermis (6). These multi-potent stem cells can migrate to the epidermis and differentiate to melanocytes.

In this report, we describe the three-dimensional skin reconstruct model which mimics human skin in architecture and composition. Melanocyte physiology, melanoma progression and the fate of dermal stem cells have been investigated using the skin reconstruct model. The model is also useful as a preclinical tool for drug assessment.

三维人体皮肤重建模型:一种工具来研究正常皮肤恶性黑色素瘤进展

Most in vitro studies in experimental skin biology have been done in 2-dimensional (2D) monocultures, while accumulating evidence suggests that cells ...

科研

生物工程

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

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

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

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

循环压力为生物反应器的设计体外主动脉心脏瓣膜的研究

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

Fabrication and Application of Rose Bengal-chitosan Films in Laser Tissue Repair

Photochemical tissue bonding (PTB) is a sutureless technique for tissue repair, which is achieved by applying a solution of rose bengal (RB) between two tissue edges1,2. These are then irradiated by a laser that is selectively absorbed by the RB. The resulting photochemical reactions supposedly crosslink the collagen fibers in the tissue with minimal heat production3. In this report, RB has been incorporated in thin chitosan films to fabricate a novel tissue adhesive that is laser-activated. Adhesive films, based on chitosan and containing ~0.1 wt% RB, are fabricated and bonded to calf intestine and rat tibial nerves by a solid state laser (&lambda;=532 nm, Fluence~110 J/cm2, spot size~0.5 cm). A single-column tensiometer, interfaced with a personal computer, is used to test the bonding strength. The RB-chitosan adhesive bonds firmly to the intestine with a strength of 15 &plusmn; 6 kPa, (n=30). The adhesion strength drops to 2 &plusmn; 2 kPa (n=30) when the laser is not applied to the adhesive. The anastomosis of tibial nerves can be also completed without the use of sutures. A novel chitosan adhesive has been fabricated that bonds photochemically to tissue and does not require sutures.

Sutures are usually needed to repair tissue during surgical procedures. However, their application can be problematic as they are invasive and may damage tissue. The fabrication and application methods of a novel tissue adhesive are here reported. This adhesive film is laser-activated and does not require the use of sutures.

激光对生物组织的修复孟加拉玫瑰红壳聚糖膜的制备及应用

Photochemical tissue bonding (PTB) is a sutureless technique for tissue repair, which is achieved by applying a solution of rose bengal (RB) between two ...

Manufacturing Devices and Instruments for Easier Rat Liver Transplantation

Orthotopic rat liver transplantation is a popular model, which has been shown in a recent JoVE paper with the use of the "quick-linker" device. This technique allows for easier venous cuff-anatomoses after a reasonable learning curve. The device is composed of two handles, which are carved out from scalpel blades, one approximator, which is obtained by modifying Kocher's forceps, and cuffs designed from fine-bore polyethylene tubing. The whole process can be performed at a low-cost using common laboratory material. The present report provides a step-by-step protocol for the design of the required pieces and includes stencils.

We describe the design of the &#x201C;quick-linker&#x201D; device for easier orthotopic rat liver transplantation.

大鼠肝移植更容易的制造设备和仪器

Orthotopic rat liver transplantation is a popular model, which has been shown in a recent JoVE paper with the use of the "quick-linker" device. This ...

Athymic Rat Model for Evaluation of Engineered Anterior Cruciate Ligament Grafts

Anterior cruciate ligament (ACL) rupture is a common ligamentous injury that often requires surgery because the ACL does not heal well without intervention. Current treatment strategies include ligament reconstruction with either autograft or allograft, which each have their associated limitations. Thus, there is interest in designing a tissue-engineered graft for use in ACL reconstruction. We describe the fabrication of an electrospun polymer graft for use in ACL tissue engineering. This polycaprolactone graft is biocompatible, biodegradable, porous, and is comprised of aligned fibers. Because an animal model is necessary to evaluate such a graft, this paper describes an intra-articular athymic rat model of ACL reconstruction that can be used to evaluate engineered grafts, including those seeded with xenogeneic cells. Representative histology and biomechanical testing results at 16 weeks postoperatively are presented, with grafts tested immediately post-implantation and contralateral native ACLs serving as controls. The present study provides a reproducible animal model with which to evaluate tissue engineered ACL grafts, and demonstrates the potential of a regenerative medicine approach to treatment of ACL rupture.

Animal models are important tools for the evaluation of tissue-engineered grafts. This paper presents the protocol for preparing an electrospun biodegradable polymer graft for use in anterior cruciate ligament tissue engineering, as well as a surgical protocol for implantation in a rat model.

无胸​​腺大鼠模型工程前交叉韧带移植评估

Anterior cruciate ligament (ACL) rupture is a common ligamentous injury that often requires surgery because the ACL does not heal well without ...

In Vitro Permeation of FITC-loaded Ferritins Across a Rat Blood-brain Barrier: a Model to Study the Delivery of Nanoformulated Molecules

Brain microvascular endothelial cells, supported by pericytes and astrocytes endfeet, are responsible for the low permeation of large hydrosoluble drugs through the blood-brain barrier (BBB), causing difficulties for effective pharmacological therapies. In recent years, different strategies for promoting brain targeting have aimed to improve drug delivery and activity at this site, including innovative nanosystems for drug delivery across the BBB. In this context, an in vitro approach based on a simplified cellular model of the BBB provides a useful tool to investigate the effect of nanoformulations on the trans-BBB permeation of molecules. This study describes the development of a double-layer BBB, consisting of co-cultured commercially available primary rat brain microvascular endothelial cells and astrocytes. A multiparametric approach for the validation of the model, based on the measurement of the transendothelial electrical resistance and the apparent permeability of a high molecular weight dextran, is also described. As proof of concept for the employment of this BBB model to study the effect of different nanoformulations on the translocation of fluorescent molecules across the barrier, we describe the use of fluorescein isothiocyanate (FITC), loaded into ferritin nanoparticles. The ability of ferritins to improve the trans-BBB permeation of FITC was demonstrated by flux measurements and confocal microscopy analyses. The results suggest this is a useful system for validating nanosystems for delivery of drugs across the BBB.

In Vitro Permeation of FITC-loaded Ferritins Across a Rat Blood-brain Barrier: a Model to Study the Delivery of Nanoformulated Molecules

A method to establish an in vitro model of blood-brain barrier based on a co-culture of rat brain microvascular endothelial cells and astrocytes is described and validated. This system proved to be a valid tool to study the effect of nanoformulation on the trans-barrier permeation of fluorescent molecules.

跨越大鼠血脑屏障FITC加载铁蛋白体外渗透:一个模型来研究Nanoformulated分子的交付

Brain microvascular endothelial cells, supported by pericytes and astrocytes endfeet, are responsible for the low permeation of large hydrosoluble drugs ...

Applications of In Vivo Functional Testing of the Rat Tibialis Anterior for Evaluating Tissue Engineered Skeletal Muscle Repair

Despite the regenerative capacity of skeletal muscle, permanent functional and/or cosmetic deficits (e.g., volumetric muscle loss (VML) resulting from traumatic injury, disease and various congenital, genetic and acquired conditions are quite common. Tissue engineering and regenerative medicine technologies have enormous potential to provide a therapeutic solution. However, utilization of biologically relevant animal models in combination with longitudinal assessments of pertinent functional measures are critical to the development of improved regenerative therapeutics for treatment of VML-like injuries. In that regard, a commercial muscle lever system can be used to measure length, tension, force and velocity parameters in skeletal muscle. We used this system, in conjunction with a high power, bi-phase stimulator, to measure in vivo force production in response to activation of the anterior crural compartment of the rat hindlimb. We have previously used this equipment to assess the functional impact of VML injury on the tibialis anterior (TA) muscle, as well as the extent of functional recovery following treatment of the injured TA muscle with our tissue engineered muscle repair (TEMR) technology. For such studies, the left foot of an anaesthetized rat is securely anchored to a footplate linked to a servomotor, and the common peroneal nerve is stimulated by two percutaneous needle electrodes to elicit muscle contraction and dorsiflexion of the foot. The peroneal nerve stimulation-induced muscle contraction is measured over a range of stimulation frequencies (1-200 Hz), to ensure an eventual plateau in force production that allows for an accurate determination of peak tetanic force. In addition to evaluation of the extent of VML injury as well as the degree of functional recovery following treatment, this methodology can be easily applied to study diverse aspects of muscle physiology and pathophysiology. Such an approach should assist with the more rational development of improved therapeutics for muscle repair and regeneration.

Applications of In Vivo Functional Testing of the Rat Tibialis Anterior for Evaluating Tissue Engineered Skeletal Muscle Repair

We describe an in vivo protocol to measure dorsiflexion of the foot following stimulation of the peroneal nerve and contraction of the anterior crural compartment of the rat hindlimb. Such measurements are an indispensable translational tool for evaluating skeletal muscle pathology and tissue engineering approaches to muscle repair and regeneration.

中的应用<em&gt;在体内</em&gt;评定组织的鼠胫骨前的功能测试工程化骨骼肌修复

Despite the regenerative capacity of skeletal muscle, permanent functional and/or cosmetic deficits (e.g., volumetric muscle loss (VML) resulting from ...

The Arteriovenous (AV) Loop in a Small Animal Model to Study Angiogenesis and Vascularized Tissue Engineering

A functional blood vessel network is a prerequisite for the survival and growth of almost all tissues and organs in the human body. Moreover, in pathological situations such as cancer, vascularization plays a leading role in disease progression. Consequently, there is a strong need for a standardized and well-characterized in vivo model in order to elucidate the mechanisms of neovascularization and develop different vascularization approaches for tissue engineering and regenerative medicine.
We describe a microsurgical approach for a small animal model for induction of a vascular axis consisting of a vein and artery that are anastomosed to an arteriovenous (AV) loop. The AV loop is transferred to an enclosed implantation chamber to create an isolated microenvironment in vivo, which is connected to the living organism only by means of the vascular axis. Using 3D imaging (MRI, micro-CT) and immunohistology, the growing vasculature can be visualized over time. By implanting different cells, growth factors and matrices, their function in blood vessel network formation can be analyzed without any disturbing influences from the surroundings in a well controllable environment. 
In addition to angiogenesis and antiangiogenesis studies, the AV loop model is also perfectly suited for engineering vascularized tissues. After a certain prevascularization time, the generated tissues can be transplanted into the defect site and microsurgically connected to the local vessels, thereby ensuring immediate blood supply and integration of the engineered tissue. By varying the matrices, cells, growth factors and chamber architecture, it is possible to generate various tissues, which can then be tailored to the individual patient's needs.

The Arteriovenous AV Loop in a Small Animal Model to Study Angiogenesis and Vascularized Tissue Engineering

We describe a microsurgical approach for the generation of an arteriovenous (AV) loop as a model for analyzing vascularization in vivo in an isolated and well-characterized environment. This model is not only useful for the investigation of angiogenesis, but is also optimally suited for engineering axially vascularized and transplantable tissues.

在小型动物模型的动静脉（AV）循环研究血管生成和血管组织工程

A functional blood vessel network is a prerequisite for the survival and growth of almost all tissues and organs in the human body. Moreover, in ...

The Use of a &#946;-lactamase-based Conductimetric Biosensor Assay to Detect Biomolecular Interactions

Biosensors are becoming increasingly important and implemented in various fields such as pathogen detection, molecular diagnosis, environmental monitoring, and food safety control. In this context, we used &#946;-lactamases as efficient reporter enzymes in several protein-protein interaction studies. Furthermore, their ability to accept insertions of peptides or structured proteins/domains strongly encourages the use of these enzymes to generate chimeric proteins. In a recent study, we inserted a single-domain antibody fragment into the Bacillus licheniformis BlaP &#946;-lactamase. These small domains, also called nanobodies, are defined as the antigen-binding domains of single chain antibodies from camelids. Like common double chain antibodies, they show high affinities and specificities for their targets. The resulting chimeric protein exhibited a high affinity against its target while retaining the &#946;-lactamase activity. This suggests that the nanobody and &#946;-lactamase moieties remain functional. In the present work, we report a detailed protocol that combines our hybrid &#946;-lactamase system to the biosensor technology. The specific binding of the nanobody to its target can be detected thanks to a conductimetric measurement of the protons released by the catalytic activity of the enzyme.

In this work, we report a new method to study protein-protein interactions using a conductimetric biosensor based on the hybrid &#946;-lactamase technology. This method relies on release of protons upon hydrolysis of &#946;-lactams.

基于β-酶的电导生物传感器检测技术在分子间相互作用中的应用

Biosensors are becoming increasingly important and implemented in various fields such as pathogen detection, molecular diagnosis, environmental ...

An Efficient and Reproducible Protocol for Distraction Osteogenesis in a Rat Model Leading to a Functional Regenerated Femur

This protocol describes the use of a newly developed external fixator for distraction osteogenesis in a rat femoral model. Distraction osteogenesis (DO) is a surgical technique leading to bone regeneration after an osteotomy. The osteotomized extremities are moved away from each other by gradual distraction to reach the desired elongation. This procedure is widely used in humans for lower and upper limb lengthening, treatment after a bone nonunion, or the regeneration of a bone defect following surgery for bone tumor excision, as well as in maxillofacial reconstruction. Only a few studies clearly demonstrate the efficiency of their protocol in obtaining a functional regenerated bone, i.e., bone that will support physiological weight-bearing without fracture after removal of the external fixator. Moreover, protocols for DO vary and reproducibility is limited by lack of information, making comparison between studies difficult. The aim of this study was to develop a reproducible protocol comprising an appropriate external fixator design for rat limb lengthening, with a detailed surgical technique that permits physiological weight-bearing by the animal after removal of the external fixator.

This study describes a reproducible and detailed protocol using a newly developed external fixator for distraction osteogenesis (DO) in a femoral rat model which permits physiological weight-bearing by the animal after removal of the external fixator.

大鼠牵张成骨的高效可再生性协议

This protocol describes the use of a newly developed external fixator for distraction osteogenesis in a rat femoral model. Distraction osteogenesis (DO) ...