Supported in part by National Institute of Health contracts R01-EY13178, and P30-EY08098 (Bethesda, MD), the Eye and Ear Foundation (Pittsburgh, PA), and unrestricted grants from Research to Prevent Blindness (New York, NY).

伦理声明：批准从医学匹兹堡大学的大学机构审查委员会获得的对象招募开始之前。参与研究之前提供所有受试者签署知情同意书。 1.数据采集<ol><li>压力上升<ol><li>取基线测量（眼压和OCT测量）灌输一滴0.5％丙美卡因的入眼睛。等待3分钟的疗效。 </li><li>轻轻施加压力的时间巩膜与ophthalmodynamometer，将30g在第1组，和5，然后用10克队列2。然后取所需的（眼压及OCT）测量如下<ol><li>眼压测量<ol><li>测量基线眼压。如第1.1节所述升高的压力。 </li><li>在第1组灌输一滴0.5％丙美卡因的，允许3分钟为疗效，并应用将30克的压力来巩膜。当压力被应用，测量眼压使用眼压计厂家专业如下cturer的说明。 </li><li>在第2组，灌输一滴0.5％丙美卡因的，允许3分钟为疗效，并使用ophthalmodynamometer申请将5g巩膜压力。期间使用眼压计根据制造商的说明压力上升测量眼压。 <ol><li>等待5克测定后5分钟。 </li><li>应用将10克巩膜压力ophthalmodynamometer，并使用以下制造商的说明在眼压计中压力上升测量眼压。记录在研究记录中的IOP和条件（ 即基准或10克）。 </li></ol></li></ol></li><li>华侨城扫描<ol><li>座位在OCT扫描仪的主题。输入病人的人口统计数据为新的科目，或者从先前扫描的科目华侨城数据库回忆人口统计数据。 </li><li>选择的前部部分512×128的扫描协议。居中眼在视频图像的窗口。降低扫描器之间的距离和眼睛直到角膜断层图像显示在扫描窗口</li><li>利用口头指令通过引导病人注视在鼻方向定位颞缘到扫描窗口的中心</li><li>获得基线扫描，并查看质量扫描。如果可以接受，保存，如果不能接受，重复此步骤。 <ol><li>接受扫描如果没有闪烁，并且角度被可视化在整个体积而不漂流断图像的边缘或翻转顶部。 </li></ol></li><li>灌输一滴0.5％丙美卡因的，允许3分钟的疗效，并重复步骤1.3.2至1.3.5。 </li><li>为1组，应用将30克巩膜压力ophthalmodynamometer，并获得扫描的同时施加压力的状态。卸下压力和审查质量的扫描。如果可以接受，保存，如果不能接受，重复此步骤。 </li><li>对于队列2，加5克巩膜压力ophthalmodynamomETER，并且获得在扫描的同时施加压力的状态。卸下压力和审查质量的扫描。如果可以接受，保存，如果不能接受，重复此步骤。 </li><li>等待5分钟，让眼睛从5克压力扰动中恢复过来。 </li><li>为第2组，应用将10克巩膜压力ophthalmodynamometer，并获得扫描的同时施加压力的状态。卸下压力和审查质量的扫描。如果可以接受，保存，如果不能接受，重复此步骤。 </li><li>记录扫描时间，条件在研究记录（ 即，基线或10克）和位置。 </li></ol></li></ol></li></ol></li></ol> 2.数据处理<ol><li>插头的高容量的USB存储设备插入十月从华侨城记录菜单中选择“ 导出 ”。指定一个文件位置为USB驱动器上的导出文件。取消选择“.ZIP”选项。输入SC患者姓名答要出口，并选择扫描出口。启动出口。 </li><li>当导出完成后，卸载USB驱动器，并从华侨城删除。请将包含导出图像到图像处理工作站的高容量USB驱动器。 </li><li>在这种情况下的ImageJ推出的图像处理程序。 </li><li>导入原始图像数据;选择“ 文件- &gt;导入- &gt;原始 ”从文件菜单中。选择与结尾的“_cube_raw.img”被从USB驱动器处理的文件。 </li><li>保存使用新名称导入的文件，使原来的图象数据被保存不变（http://www.ori.dhhs.gov/education/products/RIandImages）。 </li><li>进入导入参数如下，图片类型：8位，宽度：512，高度：1,024偏移：0;图片数：128。 </li><li>从插件菜单中选择“&gt; StackReg插件- - &gt;研究egistration”。然后选择“ 刚体“选项。然后选择“ 文件- &gt;另存为- &gt; TIFF”保存对齐堆栈。 </li><li>选择“ 过程- &gt;过滤器- &gt; 3D平均 ”从过程菜单。输入参数X = 1，Y = 1和Z = 1作为过滤器选项。重复此步骤两次。 </li><li>选择“ 文件- &gt;另存为- &gt; TIFF”，保存平均堆栈。旋转鼠标滚轮移动到活动的堆栈帧1。 </li><li>选择“ 过程- &gt;增强局部对比度（CLAHE）”，从处理菜单。使用参数块大小：31，直方图箱：256，最大坡度：5，面膜：没有，勾选“快速”选项。使用右箭头键前进到下一帧。 </li><li>移动到活动堆栈帧2和重复流程 - &gt;增强局部对比度（CLAHE）。重复，直到所有的帧有对比增强。 </li><li>选择“ 文件- &gt;另存为- &gt; TIFF”;保存对比增强栈。然后选择“ 图像- &gt;调整- &gt;大小 ”从图像菜单。取消选择“ 约束纵横比 ”选项，然后输入宽：2048，高：1024值。 </li><li>选择“ 图像- &gt;变换- &gt;垂直翻转 ”从图像菜单。然后选择“ 分析- &gt;设置比例 ”，从分析菜单。以像素为单位输入距离：2048，已知的距离：4000，而像素长宽比：1，然后单击确定。选择“ 文件- &gt;另存为- &gt; TIFF”，保存校准1：1宽高比堆栈。 </li><li>慢慢转动鼠标滚轮来直观地检查扫描，以确定一个鲜明的船只穿越作为一个点的扫描范围内引用。记录在分析电子表格中的图像数目和参考帧号。 </li><li>按左方向键15次赴第一次测量框架。选择“写意SelectionsR21;从工具栏。 </li><li>鼠标放置在SC的中心，按向上箭头。重复此步骤，直到SC充满屏幕。 </li><li>手动段SC由盘旋的边界用鼠标。按住控制（Ctrl）键，然后按D当前图像帧。按住Ctrl键，然后按M.转录SC截面积和测量帧数的测量分析电子表格。取消选择的轮廓区域。按右箭头键3次。直到SC已经在10帧为单位重复此步骤。 </li><li>按左方向键30次返回到第一测量框架。 </li><li>从工具栏中选择直线段工具。 </li><li>借鉴SC上最前到最靠后的位置的直线。按住Ctrl键，然后按D仅当前帧。按住Ctrl键，然后按M.抄表SC长度和帧数来分析电子表格。取消选择的轮廓区域。按下右箭头键3次。直到SC长度已在相同的10帧作为对SC截面积被测量重复此步骤。 </li><li>插入公式SC-IOWD = SC-CSA /轴向长度到电子表格分析除以面积测量的长度测量计算平均SC内壁至外壁的距离（SC-IOWD）。 </li><li>按左方向键30次返回到第一测量框架。 </li><li>从工具栏中选择直线段工具。 </li><li>从画一条直线最前的​​SC到小梁网和前室的边界。确保线垂直于边界。按住Ctrl键，然后按D，然后M. </li><li>绘制从SC的最靠后的位置和TM的边界和前房的线。确保垂直于边界线。按住控制并按下D，则M. </li><li>绘制从SC的中心和TM的边界和前房的线。确保林Ë垂直边界。按住Ctrl键，然后按D仅当前帧。 </li><li>录制三个TM厚度测量和帧号到分析电子表格。要做到这一点按右箭头键3次。直到TM厚度已经在相同的10帧作为对SC截面积被测量重复此步骤。 </li></ol>

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舒曼博士收到版权费知识产权由美国麻省理工学院和马萨诸塞州眼耳医院蔡司公司许可

本技术利用非侵入性的观察软组织的机械响应量化的SC崩溃。利用人类尸体的眼睛今后的工作中，需要解剖后校准组织变形实际组织硬度。但是，这样的研究将遭受先前流出模型的相同的限制;具体地，该活肌到组织张力的贡献将不存在。在哺乳动物活眼模型进一步校准可以让影像和TM的刚度直接测量校准。 有几个限制的技术。它尚待证实在其他平台华侨城。该文献表明，相同...

青光眼是全球第二大不可逆转的失明1的原因。升高的眼内压（IOP）是用于青光眼2-7的存在和发展的主要致病危险因素。 &#160;眼压是由房水8的形成和流出之间的平衡调节。最大流出阻力的位置是juxtacanicular组织和Schlemm管（SC）的内壁，SC和小梁网（TM）9-11之间的接口。而TM刚度可以在IOP升高的脸向预防SC崩溃，奥弗等人 12最近证明在青光眼基因表达被改变，从而提高SC内皮变硬，妨碍形成气孔，导致高眼压中青光眼13。 TM形态和刚度与相关设施的流出14,15，强调牛逼他需要测量其生物力学特性。 以旧换新的原子力显微镜测量表明高架刚度眼青光眼患者（81千帕）捐赠的眼睛捐助者无青光眼（4.0千帕）16相比，但这些测量是在解剖离体组织进行。后TM被锚定到经由纵肌细胞中插入到外lamellated和cribiform TM 17的前肌腱睫状肌。睫状肌（CM）的活动可能会增加TM绷紧，酷似TM升高17的刚度。观察改建耐诱导的平滑肌扰动SC崩溃的能力已经显示出在动物模型18。我们已经证明了能够非侵入性图像的主房水外流系统在活的人的眼睛的远端并包括SC使用谱域光学相干断层扫描（OCT）&lt;SUP&gt; 19-21。使用这种技术，我们已经证明，量化TM和SC急性IOP升高22的形态反应的能力。 本文所描述的方法的总体目标是量化活流出道急性IOP升高的在生物体组织中原位形态响应。这种技术具有检查在生理条件下对TM，其中既包括收缩纤维活性的T M和CM以TM刚度内贡献相比，在解剖组织制成公布的测量的优点。背后采用这种技术来观察机械TM响应的理由是，它为我们提供了其他原因无法分析上市公司以旧换新，我们现在知道被直接链接到水流出阻力，眼压第13条的力学性能。辨别收缩组织对整体刚度，小的银的贡献受试者室温进行了检查，并没有与抑制平滑肌的活动由托的管理。

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Spectral Domain OCT</td>
			<td>Zeiss</td>
			<td>Cirrus</td>
			<td></td>
		</tr>
		<tr>
			<td>Imaging Workstation</td>
			<td>Apple</td>
			<td>iMac</td>
			<td></td>
		</tr>
		<tr>
			<td>Ophthalmodynamometer</td>
			<td colspan="3">(Baillairt Matalene Ophthalmodynamometer, Surgical instruments CO., Inc. New York, NY)</td>
		</tr>
		<tr>
			<td>Image Processing Program</td>
			<td>rsb.info.nih.gov/ij</td>
			<td>ImageJ, FIJI</td>
			<td></td>
		</tr>
	</tbody>
</table>

trabecular meshwork response to pressure elevation in the living human eye

小梁网（TM）的机械特性都与流出阻力和眼内压（IOP）调节。这种技术背后的基本原理是直接观察以旧换新急性眼压升高的机械反应。在扫描之前，眼压测量在基线和在IOP升高。角膜缘是在基线和在高眼压扫描谱域光学相干断层扫描（ophthalmodynamometer（ODM）施加于30挤压力g）。扫描处理，以提高使用ImageJ房水外流通路的可视化。血管地标被用于识别在基线和高眼压扫描体积相对应的位置。 Schlemm管（SC）的截面积（SC-CSA）和由前向沿其长轴后路SC长度手动在SC的1毫米段内10个位置测量。平均数内到外壁上的距离（短轴长度）计算为SC的由划分区域其长轴长度。为了检查邻近组织的效果的IOP升高的贡献，重复测量不具有和具有平滑肌松弛与托滴注。 TM迁移进入SC由TM刚度抵抗，但由它附着到相邻的平滑肌睫状体内的支持增强。这种技术是在第一测量生理条件下，人眼内的活的人类TM响应于压力上升的原位 。

利用这些数据采集和图像分析技术，对流出道形态学参数眼压小和大的变化，如SC截面积的影响，获得（ 图1）。我们可以看到，水平高的眼压增加产生的SC的可观察到的塌陷，因为由大的减少的截面面积表示。眼睛看来是能够容纳小增加眼压，就证明了缺乏变化的SC-CSA的（ 图1）。这些结果表明，该技术能够定量流出道的锐角眼压挑战的形态反应。技术或技术没有其他家?...

Watch this Scientific Journal Video about Trabecular Meshwork Response to Pressure Elevation in the Living Human Eye at JoVE.com

Trabecular Meshwork Response to Pressure Elevation in the Living Human Eye

小梁网（TM）迁移进入施累姆氏管的空间可以由急性压力上升来诱导由ophthalmodynamometer，并通过谱域光学相干断层扫描观察。该方法的目标是要量化活流出道急性压力升高的在生物体组织的原位的形态反应。

小梁响应压升高在活的人类眼睛

The mechanical characteristics of the trabecular meshwork (TM) are linked to outflow resistance and intraocular pressure (IOP) regulation. The rationale ...

trabecular-meshwork-response-to-pressure-elevation-living-human

Research

JoVE Journal

Medicine

9.9K 次观看.  University of Pittsburgh School of Medicine. 小梁网（TM）迁移进入施累姆氏管的空间可以由急性压力上升来诱导由ophthalmodynamometer，并通过谱域光学相干断层扫描观察。该方法的目标是要量化活流出道急性压力升高的在生物体组织的原位的形态反应。 

视频: Trabecular Meshwork Response to Pressure Elevation in the Living Human Eye

Epidural Intracranial Pressure Measurement in Rats Using a Fiber-optic Pressure Transducer

Elevated intracranial pressure (ICP) is a significant problem in several forms of ischemic brain injury including stroke, traumatic brain injury and cardiac arrest. This elevation may result in further neurological injury, in the form of transtentorial herniation1,2,3,4, midbrain compression, neurological deficit or increased cerebral infarct2,4. Current therapies are often inadequate to control elevated ICP in the clinical setting5,6,7 . Thus there is a need for accurate methods of ICP measurement in animal models to further our understanding of the basic mechanisms and to develop new treatments for elevated ICP.
In both the clinical and experimental setting ICP cannot be estimated without direct measurement. Several methods of ICP catheter insertion currently exist. Of these the intraventricular catheter has become the clinical 'gold standard' of ICP measurement in humans8. This method involves the partial removal of skull and the instrumentation of the catheter through brain tissue. Consequently, intraventricular catheters have an infection rate of 6-11%9. For this reason, subdural and epidural cannulations have become the preferred methods in animal models of ischemic injury. 
Various ICP measurement techniques have been adapted for animal models, and of these, fluid-filled telemetry catheters10 and solid state catheters are the most frequently used11,12,13,14,15. The fluid-filled systems are prone to developing air bubbles in the line, resulting in false ICP readings. Solid state probes avoid this problem (Figure 1). An additional problem is fitting catheters under the skull or into the ventricles without causing any brain injury that might alter the experimental outcomes. Therefore, we have developed a method that places an ICP catheter contiguous with the epidural space, but avoids the need to insert it between skull and brain. 
An optic fibre pressure catheter (420LP, SAMBA Sensors, Sweden) was used to measure ICP at the epidural location because the location of the pressure sensor (at the very tip of the catheter) was found to produce a high fidelity ICP signal in this model. There are other manufacturers of similar optic fibre technologies13 that may be used with our methodology. Alternative solid state catheters, which have the pressure sensor located at the side of the catheter tip, would not be appropriate for this model as the signal would be dampened by the presence of the monitoring screw. 
Here, we present a relatively simple and accurate method to measure ICP. This method can be used across a wide range of ICP related animal models.

A novel technique to record the pressures within the skull is described. The minimally invasive method uses a fibre-optic pressure sensing system to accurately measure intracranial pressure (ICP) in anaesthetized rats without causing significant brain trauma. The technique may be used in a wide range of experimental models.

硬膜外颅内压测量中使用的光纤压力传感器的大鼠

Elevated intracranial pressure (ICP) is a significant problem in several forms of ischemic brain injury including stroke, traumatic brain injury and ...

科研

医学

Subretinal Injection of Gene Therapy Vectors and Stem Cells in the Perinatal Mouse Eye

The loss of sight affects approximately 3.4 million people in the United States and is expected to increase in the upcoming years.1 Recently, gene therapy and stem cell transplantations have become key therapeutic tools for treating blindness resulting from retinal degenerative diseases. Several forms of autologous transplantation for age-related macular degeneration (AMD), such as iris pigment epithelial cell transplantation, have generated encouraging results, and human clinical trials have begun for other forms of gene and stem cell therapies.2 These include RPE65 gene replacement therapy in patients with Leber's congenital amaurosis and an RPE cell transplantation using human embryonic stem (ES) cells in Stargardt's disease.3-4 Now that there are gene therapy vectors and stem cells available for treating patients with retinal diseases, it is important to verify these potential therapies in animal models before applying them in human studies. The mouse has become an important scientific model for testing the therapeutic efficacy of gene therapy vectors and stem cell transplantation in the eye.5-8 In this video article, we present a technique to inject gene therapy vectors or stem cells into the subretinal space of the mouse eye while minimizing damage to the surrounding tissue.

This surgical technique illustrates the injection of gene therapy vectors and stem cells into the subretinal space of the mouse eye.

基因治疗的载体和干细胞视网膜下注射到老鼠的眼睛

The loss of sight affects approximately 3.4 million people in the United States and is expected to increase in the upcoming years.1 Recently, gene therapy ...

Development of an Audio-based Virtual Gaming Environment to Assist with Navigation Skills in the Blind

Audio-based Environment Simulator (AbES) is virtual environment software designed to improve real world navigation skills in the blind. Using only audio based cues and set within the context of a video game metaphor, users gather relevant spatial information regarding a building's layout. This allows the user to develop an accurate spatial cognitive map of a large-scale three-dimensional space that can be manipulated for the purposes of a real indoor navigation task. After game play, participants are then assessed on their ability to navigate within the target physical building represented in the game. Preliminary results suggest that early blind users were able to acquire relevant information regarding the spatial layout of a previously unfamiliar building as indexed by their performance on a series of navigation tasks. These tasks included path finding through the virtual and physical building, as well as a series of drop off tasks. We find that the immersive and highly interactive nature of the AbES software appears to greatly engage the blind user to actively explore the virtual environment. Applications of this approach may extend to larger populations of visually impaired individuals.

Audio-based Environment Simulator (AbES) is virtual environment software designed to improve real world navigation skills in the blind.

基于音频的虚拟游戏环境的发展，以帮助盲人的导航技巧

Audio-based Environment Simulator (AbES) is virtual environment software designed to improve real world navigation skills in the blind. Using only audio ...

Assessing Myogenic Response and Vasoactivity In Resistance Mesenteric Arteries Using Pressure Myography

Small resistance arteries constrict and dilate respectively in response to increased or decreased intraluminal pressure; this phenomenon known as myogenic response is a key regulator of local blood flow. In isobaric conditions small resistance arteries develop sustained constriction known as myogenic tone (MT), which is a major determinant of systemic vascular resistance (SVR). Hence, ex vivo&#160;pressurized preparations of small resistance arteries are major tools to study microvascular function in near-physiological states. To achieve this, a freshly isolated intact segment of a small resistance artery (diameter ~260 &#956;m) is mounted onto two small glass cannulas and pressurized. These arterial preparations retain most in vivo characteristics and permit assessment of vascular tone in real-time. Here we provide a detailed protocol for assessing vasoactivity in pressurized small resistance mesenteric arteries from rats; these arteries develop sustained vasoconstriction - approximately 25% of maximal diameter - when pressurized at 70 mmHg. These arterial preparations may be used to study the effect of investigational compounds on relationship between intra-arterial pressure and vasoactivity and determine changes in microvascular function in animal models of various diseases.

Pressure myography is used to assess vasoactivity of small arteries that develop sustained constriction when pressurized. This manuscript provides a detailed protocol to assess in isolated segments of small mesenteric arteries from rats, vasoactivity and the effect of intraluminal pressure on vascular diameter.

评估肌反应及血管活性阻力肠系膜动脉使用压力肌动描记

Small resistance arteries constrict and dilate respectively in response to increased or decreased intraluminal pressure; this phenomenon known as myogenic ...

Intrauterine Telemetry to Measure Mouse Contractile Pressure In Vivo

A complex integration of molecular and electrical signals is needed to transform a quiescent uterus into a contractile organ at the end of pregnancy. Despite the discovery of key regulators of uterine contractility, this process is still not fully understood. Transgenic mice provide an ideal model in which to study parturition. Previously, the only method to study uterine contractility in the mouse was ex vivo isometric tension recordings, which are suboptimal for several reasons. The uterus must be removed from its physiological environment, a limited time course of investigation is possible, and the mice must be sacrificed. The recent development of radiometric telemetry has allowed for longitudinal, real-time measurements of in vivo intrauterine pressure in mice. Here, the implantation of an intrauterine telemeter to measure pressure changes in the mouse uterus from mid-pregnancy until delivery is described. By comparing differences in pressures between wild type and transgenic mice, the physiological impact of a gene of interest can be elucidated. This technique should expedite the development of therapeutics used to treat myometrial disorders during pregnancy, including preterm labor.

Intrauterine Telemetry to Measure Mouse Contractile Pressure In Vivo

This manuscript provides a protocol for implanting telemeters in the mouse for the purpose of measuring intrauterine pressures during pregnancy.

宫内遥测来衡量鼠标收缩压力<em&gt;在体内</em

A complex integration of molecular and electrical signals is needed to transform a quiescent uterus into a contractile organ at the end of pregnancy. ...

Cardiac Catheterization in Mice to Measure the Pressure Volume Relationship: Investigating the Bowditch Effect

Animal models that mimic human cardiac disorders have been created to test potential therapeutic strategies. A key component to evaluating these strategies is to examine their effects on heart function. There are several techniques to measure in vivo cardiac mechanics (e.g., echocardiography, pressure/volume relations, etc.). Compared to echocardiography, real-time left ventricular (LV) pressure/volume analysis via catheterization is more precise and insightful in assessing LV function. Additionally, LV pressure/volume analysis provides the ability to instantaneously record changes during manipulations of contractility (e.g., &#946;-adrenergic stimulation) and pathological insults (e.g., ischemia/reperfusion injury). In addition to the maximum (+dP/dt) and minimum (-dP/dt) rate of pressure change in the LV, an accurate assessment of LV function via several load-independent indexes (e.g., end systolic pressure volume relationship and preload recruitable stroke work) can be attained. Heart rate has a significant effect on LV contractility such that an increase in the heart rate is the primary mechanism to increase cardiac output (i.e., Bowditch effect). Thus, when comparing hemodynamics between experimental groups, it is necessary to have similar heart rates. Furthermore, a hallmark of many cardiomyopathy models is a decrease in contractile reserve (i.e., decreased Bowditch effect). Consequently, vital information can be obtained by determining the effects of increasing heart rate on contractility. Our and others data has demonstrated that the neuronal nitric oxide synthase (NOS1) knockout mouse has decreased contractility. Here we describe the procedure of measuring LV pressure/volume with increasing heart rates using the NOS1 knockout mouse model.

This article describes the measurement of murine left ventricular function via pressure/volume analysis at different heart rates.

心导​​管在小鼠测量压力体积的关系：调查的影响鲍迪奇

Animal models that mimic human cardiac disorders have been created to test potential therapeutic strategies. A key component to evaluating these ...

A Mouse Model of Retinal Ischemia-Reperfusion Injury Through Elevation of Intraocular Pressure

Retinal ischemia-reperfusion (I/R) is a pathophysiological process contributing to cellular damage in multiple ocular conditions, including glaucoma, diabetic retinopathy, and retinal vascular occlusions. Rodent models of I/R injury are providing significant insights into mechanisms and treatment strategies for human I/R injury, especially with regard to neurodegenerative damage in the retinal neurovascular unit. Presented here is a protocol for inducing retinal I/R injury in mice through elevation of intraocular pressure (IOP). In this protocol, the ocular anterior chamber is cannulated with a needle, through which flows the drip of an elevated saline reservoir. Using this drip to raise IOP above systolic arterial blood pressure, a practitioner temporarily halts inner retinal blood flow (ischemia). When circulation is reinstated (reperfusion) by removal of the cannula, severe cellular damage ensues, resulting ultimately in retinal neurodegeneration. Recent studies demonstrate inflammation, vascular permeability, and capillary degeneration as additional elements of this model. Compared to alternative retinal I/R methodologies, such as retinal arterial ligation, retinal I/R injury by elevated IOP offers advantages in its&#160;anatomical specificity, experimental tractability, and technical accessibility, presenting itself as a valuable tool for examining neuronal pathogenesis and therapy in the retinal neurovascular unit.

This article describes a procedure for inducing retinal ischemia-reperfusion injury by elevated intraocular pressure in mice. Retinal ischemia-reperfusion injury by elevated intraocular pressure serves to model human pathologies characterized by compromised oxygen and nutrient delivery in the retina, enabling researchers to examine potential cellular mechanisms and treatments for human diseases of the retinal neurovascular unit.

视网膜缺血再灌注损伤的小鼠模型通过眼压升高

Retinal ischemia-reperfusion (I/R) is a pathophysiological process contributing to cellular damage in multiple ocular conditions, including glaucoma, ...

Precision Implementation of Minimal Erythema Dose (MED) Testing to Assess Individual Variation in Human Inflammatory Response

Minimal erythema dose (MED) testing is frequently used in clinical settings for determining the smallest amount of ultraviolet (UV) irradiation necessary to produce erythema (inflammatory reddening) on the surface of the skin. In this context, the MED is regarded as a key factor in determining starting doses for UV phototherapy for common skin conditions such as psoriasis and eczema. In research settings, MED testing also has potential to be a powerful tool for assessing within- and between-persons variation in inflammatory responses. However, MED testing has not been widely adopted for use in research settings, likely owing to a lack of published guidelines, which is a barrier to obtaining reproducible results from this assay. Also, protocols and equipment for establishing MED vary widely, making it difficult to compare results across laboratories. Here, we describe a precise and reproducible method to induce and measure superficial erythema using newly designed protocols and methods that can easily be adapted to other equipment and laboratory environments. The method described here includes detail on procedures that will allow extrapolation of a standardized dosage schedule to other equipment so that this protocol can be adapted to any UV radiation source.

Precision Implementation of Minimal Erythema Dose MED Testing to Assess Individual Variation in Human Inflammatory Response

Minimal erythema dose (MED) testing is used to establish dosage schedules for ultraviolet radiation phototherapy. It can assess individual variation in inflammatory response but lacks methodology for achieving reproducible results. Here, we present a precision implementation of MED and demonstrate its ability to capture individual variation in inflammatory response.

精确实施最小红斑剂量（MED）测试，以评估人体炎症反应中的个体变异

Minimal erythema dose (MED) testing is frequently used in clinical settings for determining the smallest amount of ultraviolet (UV) irradiation necessary ...

Characterization of a Novel Human Organotypic Retinal Culture Technique

Previous human organotypic retinal culture (HORC) models have utilized detached retinas; however, without the structural support conferred by retinal pigment epithelium-choroid (RPE-choroid) and sclera, the integrity of the fragile retina can easily be compromised. The aim of this study was to develop a novel HORC model that contains the retina, RPE-choroid and sclera to maintain retinal integrity when culturing retinal explants.
After cutting circumferentially along the limbus to remove iris and lens, four deep incisions were made to flatten the eyecup. In contrast to previous HORC protocols, a trephine was used to cut through not only the retina but also the RPE-choroid and sclera. The resultant triple-layered explants were cultured for 72 h. Hematoxylin and Eosin staining (H&#38;E) was used to assess anatomical structures and retinal explants were further characterized by immunohistochemistry (IHC) for apoptosis, M&#252;ller cell integrity and retinal inflammation. To confirm the possibility of disease induction, explants were exposed to high glucose (HG) and pro-inflammatory cytokines (Cyt), to mimic diabetic retinopathy (DR). The Luminex magnetic bead assay was used to measure DR-related cytokines released into the culture medium.
H&#38;E staining revealed distinct retinal lamellae and compact nuclei in retinal explants with the underlying RPE-choroid and sclera, while retinas without the underlying structures exhibited reduced thickness and severe nuclei loss. IHC results indicated absence of apoptosis and retinal inflammation as well as preserved M&#252;ller cell integrity. The Luminex&#160;assays showed significantly increased secretion of DR-associated pro-inflammatory cytokines in retinal explants exposed to HG + Cyt relative to baseline levels at 24 h.
We successfully developed and characterized a novel HORC protocol in which retinal integrity was preserved without apoptosis or retinal inflammation. Moreover, the induced secretion of DR-associated pro-inflammatory biomarkers when exposing retinal explants to HG + Cyt suggests that this model could be used for clinically translatable retinal disease studies.

This study aims to develop a novel human organotypic retinal culture (HORC) model that prevents compromising retinal integrity during explant handling. This is achieved by culturing the retina with the overlying vitreous and the underlying retinal pigment&#160;epithelium-choroid (RPE-choroid) and sclera.

新型人类组织特征视网膜培养技术的特征

Previous human organotypic retinal culture (HORC) models have utilized detached retinas; however, without the structural support conferred by retinal ...

Cardiac Response to &#946;-Adrenergic Stimulation Determined by Pressure-Volume Loop Analysis

Determination of the cardiac function is a robust endpoint analysis in animal models of cardiovascular diseases in order to characterize effects of specific treatments on the heart. Due to the feasibility of genetic manipulations the mouse has become the most common mammalian animal model to study cardiac function and to search for new potential therapeutic targets. Here we describe a protocol to determine cardiac function&#160;in vivo using pressure-volume loop measurements and analysis during basal conditions and under &#946;-adrenergic stimulation by intravenous infusion of increasing concentrations of isoproterenol. We provide a refined protocol including ventilation support taking into account the positive end-expiratory pressure to ameliorate negative effects during open-chest measurements, and potent analgesia (Buprenorphine) to avoid uncontrollable myocardial stress evoked by pain during the procedure. All together the detailed description of the procedure and discussion about possible pitfalls enables highly standardized and reproducible pressure-volume loop analysis, reducing the exclusion of animals from the experimental cohort by preventing possible methodological bias.

Cardiac Response to &amp;#946;-Adrenergic Stimulation Determined by Pressure-Volume Loop Analysis

Here we describe a cardiac pressure-volume loop analysis under increasing doses of intravenously infused isoproterenol to determine the intrinsic cardiac function and the &#946;-adrenergic reserve in mice. We use a modified open-chest approach for the pressure-volume loop measurements, in which we include ventilation with positive end-expiratory pressure.

通过压力-体积环路分析确定心脏对β肾上腺素能刺激的反应

Determination of the cardiac function is a robust endpoint analysis in animal models of cardiovascular diseases in order to characterize effects of ...