Name: real-time, two-color stimulated raman scattering imaging of mouse brain for tissue diagnosis
Uploaded: 2022-02-01T14:40:00
Description: Watch this Scientific Journal Video about Real-Time, Two-Color Stimulated Raman Scattering Imaging of Mouse Brain for Tissue Diagnosis at JoVE.com

这项研究得到了NIH R35 GM133435至D.F.的支持。

所有实验动物程序均根据华盛顿大学动物护理和使用委员会研究所（IACUC）批准的协议（#4395-01）使用200μm，固定，切片的小鼠大脑进行。野生型小鼠（C57BL / 6J菌株）用CO2安乐死。然后，进行开颅手术以提取他们的大脑以固定在磷酸盐缓冲盐水中的4%多聚甲醛中。将大脑嵌入3%琼脂糖和0.3%明胶混合物中，并通过振动切片机切片成200μm厚的切片。
1. 初始对齐</...

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该协议中介绍的双色SRS成像方案取决于单色SRS成像的正确实施。在单色SRS成像中，关键步骤是空间对准、时间对准、调制深度和相移。在空间上，两个光束的组合是通过二向色镜完成的。在将光束发送到二向色镜时，使用几个转向镜进行微调。一旦光束与二向色镜组合，就可以通过用镜子选择组合光束路径以发送到>1 m外的墙壁来确认空间对齐，同时检查组合光束以查看它是否与IR卡重叠。通过显?...

传统的组织诊断依赖于染色方案，然后在光学显微镜下进行检查。病理学家使用的一种常见染色方法是H&E染色：苏木精将细胞核染色为紫蓝色，曙红将细胞外基质染色为粉红色。这种简单的染色仍然是许多组织诊断任务的病理学的金标准，特别是癌症诊断。然而，H&E组织病理学，特别是在术中环境中使用的冷冻切片技术，仍然存在局限性。染色过程是一个费力的过程，涉及组织包埋，切片，固定和染色1。典型的周转时间为20分钟或更长时间。当一次处理多个切片时，在冷冻切片期间执行H&E有时会变得更具挑战性，因为需要在3D中评估细胞特征或生长模式以进行边缘评估。此外，术中组织学技术需要熟练的技术人员和临床医生。在许多情况下，许多医院董事会认证的病理学家数量的限制是术中咨询的一个限制因素。随着数字病理学和基于人工智能的诊断的快速发展兴趣，这种局限性可能会得到缓解2.然而，根据技术人员的经验，H&E染色结果是可变的，这给基于计算机的诊断带来了额外的挑战2。
这些挑战可以通过无标记光学成像技术来解决。其中一种技术是SRS显微镜。SRS 使用同步脉冲激光器（泵浦和斯托克斯）以高效率激发分子振动3.最近的报告表明，蛋白质和脂质的SRS成像可以产生具有完整新鲜组织的H&E等效图像（也称为刺激拉曼组织学或SRH），这绕过了任何组织处理的需要，显着缩短了诊断所需的时间，并且已经在术中进行了调整4。此外，SRS成像可以提供3D图像，当2D图像不足时，它为诊断提供了额外的信息5。SRH是无偏倚的，并生成随时可用于基于计算机的诊断的数字图像。它很快成为术中癌症诊断和肿瘤边缘分析的可能解决方案，特别是在脑癌中6，7，8。最近，还建议对组织的化学变化进行SRS成像，以提供有用的诊断信息，进一步帮助临床医生对不同的癌症类型或9期进行分层。
尽管SRS成像在组织诊断应用中具有巨大的潜力，但由于成像平台的复杂性，包括超快激光器，激光扫描显微镜和复杂的检测电子设备，SRS成像主要局限于专门从事光学的学术实验室。该协议提供了一个详细的工作流程，以演示使用常见的飞秒激光源进行实时双色SRS成像以及从小鼠脑组织生成伪H&E图像。该协议将涵盖以下过程：
对齐和啁啾优化 大多数SRS成像方案使用皮秒或飞秒激光器作为激发源。对于飞秒激光器，激光器的带宽远大于拉曼线宽。为了克服这一限制，使用光谱聚焦方法将飞秒激光器啁啾到皮秒时间尺度，以实现窄光谱分辨率10。只有当时间啁啾（也称为群延迟色散或仅色散）与泵浦和斯托克斯激光器正确匹配时，才能实现最佳光谱分辨率。这里演示了使用高色散玻璃棒优化激光束色散的对准过程和步骤。
频率校准 光谱聚焦SRS的一个优点是，可以通过改变泵浦和斯托克斯激光器之间的时间延迟来快速调谐拉曼激发。与调谐激光波长相比，这种调谐提供了快速成像和可靠的光谱采集。然而，激励频率和时间延迟之间的线性关系需要外部校准。具有已知拉曼峰的有机溶剂用于校准光谱聚焦SRS的拉曼频率。
实时双色成像 提高组织诊断应用中的成像速度以缩短分析大型组织标本所需的时间非常重要。同时对脂质和蛋白质进行双色SRS成像，无需调整激光或延时，从而使成像速度提高了两倍以上。这是通过使用一种新颖的正交调制技术和带有锁相放大器11的双通道解调来实现的。本文介绍了正交调制和双通道图像采集的协议。
外延模式 SRS 成像 迄今为止显示的大多数SRS成像都是在传输模式下进行的。Epi模式成像检测来自组织12的反向散射光子。对于病理学应用，手术标本可能相当大。对于透射模式成像，通常需要组织切片，这不需要额外的时间。相比之下，表观成像可以处理完整的手术标本。由于使用相同的物镜来收集反向散射光，因此也不需要对准透射成像所需的高数值孔径聚光镜。当组织切片困难时，外延模式也是唯一的选择，例如骨骼。以前我们已经证明，对于脑组织，外延模式成像为组织厚度>2 mm13提供了卓越的成像质量。该协议使用偏振分束器（PBS）来收集由组织去极化的散射光子。可以用环形探测器收集更多的光子，但代价是定制探测器组件12的复杂性。PBS方法更易于实现（类似于荧光），标准光电二极管已经用于传输模式检测。
伪 H&E 图像生成 一旦收集了双色SRS图像，就可以对其进行重新着色以模拟H&E染色。本文演示了将脂质和蛋白质SRS图像转换为伪H&E SRS图像以用于病理学应用的过程。实验方案详细说明了生成高质量SRS图像所需的关键步骤。这里显示的程序不仅适用于组织诊断，而且可以适用于许多其他高光谱SRS成像应用，例如药物成像和代谢成像14，15。
一般系统要求 用于该协议的激光系统必须能够输出2个同步飞秒激光束。理想情况下，系统具有光学参数振荡器（OPO），用于其中一束激光束的宽波长调谐。该协议中的设置使用商用激光系统Insight DS+，该系统输出两个激光器（一个1，040 nm的固定光束和一个基于OPO的可调谐光束，范围从680到1，300 nm），重复率为80 MHz。使用的显微镜是建立在商用正置显微镜框架之上的直立激光扫描显微镜。一对5毫米振镜用于扫描激光束。对于选择采用自制激光扫描显微镜的用户，请参阅先前发布的激光扫描显微镜构建方案16。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>100 mm Achromatic Lens</td>
			<td>THORLABS</td>
			<td>AC254-100-B</td>
			<td>Broadband, 650 - 1,050 nm, achromatic lens focal length, 100 mm</td>
		</tr>
		<tr>
			<td>20 MHz bandpass filter</td>
			<td>Minicircuits</td>
			<td>BBP-21.4+</td>
			<td>Lumped LC Band Pass Filter, 19.2 - 23.6 MHz, 50 &#937;</td>
		</tr>
		<tr>
			<td>200 mm Achromatic Lens</td>
			<td>THORLABS</td>
			<td>AC254-200-B</td>
			<td>Broadband, 650 - 1,050 nm, achromatic lens focal length, 200 mm</td>
		</tr>
		<tr>
			<td>Achromatic Half Waveplate</td>
			<td>Union Optic</td>
			<td>WPA2210-650-1100-M25.4</td>
			<td>Broadband half waveplate</td>
		</tr>
		<tr>
			<td>Achromatic Quarter Waveplate</td>
			<td>Union Optic</td>
			<td>WPA4210-650-1100-M25.4</td>
			<td>Broadband quarter waveplate</td>
		</tr>
		<tr>
			<td>Beam Sampler</td>
			<td>THORLABS</td>
			<td>BSN11</td>
			<td>10:90 Plate Beamsplitter</td>
		</tr>
		<tr>
			<td>Dichroic Mirror</td>
			<td>THORLABS</td>
			<td>DMSP1000</td>
			<td>Other dichroics with a center wavelength around 1,000 nm can be used.</td>
		</tr>
		<tr>
			<td>DMSO (Dimethyl sulfoxide)</td>
			<td>Sigma Aldrich</td>
			<td>472301</td>
			<td>Solvent for calibration of Raman shift. Other solvents with known Raman peaks can be used.</td>
		</tr>
		<tr>
			<td>Electrooptic Amplitude Modulator</td>
			<td>THORLABS</td>
			<td>EO-AM-NR-C1</td>
			<td>Two EOMs are needed for orthogonal modulation and dual-channel imaging. Resonant version is recommended so lower driving voltage can be used.</td>
		</tr>
		<tr>
			<td>False H&#38;E Staining Script</td>
			<td>Matlab</td>
			<td></td>
			<td>https://github.com/TheFuGroup/HE_Staining</td>
		</tr>
		<tr>
			<td>Fanout Buffer</td>
			<td>PRL-414B</td>
			<td>Pulse Research Lab</td>
			<td>1:4 TTL/CMOS Fanout Buffer and Line Driver, for generating the EOM driving frequency and the reference to the lock-in</td>
		</tr>
		<tr>
			<td>Fast Photodiode</td>
			<td>THORLABS</td>
			<td>DET10A2</td>
			<td>Si Detector, 1 ns Rise Time</td>
		</tr>
		<tr>
			<td>Frequency Divider</td>
			<td>PRL-220A</td>
			<td>Pulse Research Lab</td>
			<td>TTL Freq. Divider (f/2, f/4, f/8, f/16), for generating 20MHz from the laser output.</td>
		</tr>
		<tr>
			<td>Highly Dispersive Glass Rods</td>
			<td>Union Optic</td>
			<td>CYLROD01</td>
			<td>High dispersion H-ZF52A Rod lens 120 mm, SF11 Rod lens 100 mm</td>
		</tr>
		<tr>
			<td>Insight DS+</td>
			<td>Newport</td>
			<td></td>
			<td>Laser system capable of outputting two synchronzied pulsed lasers (one fixed beam at 1, 040 nm and one tunable beam, ranging from 680-1,300 nm) with a repetition rate of 80 MHz.&#160;</td>
		</tr>
		<tr>
			<td>Lock-in Amplifier</td>
			<td>Liquid Instruments</td>
			<td>Moku Lab</td>
			<td>Lock-in amplifier to extract SRS signal from the photodiode. A Zurich Instrument HF2LI or similar instrument can be used as well.</td>
		</tr>
		<tr>
			<td>Mirrors</td>
			<td>THORLABS</td>
			<td>BB05-E03-10</td>
			<td>Broadband Dielectric Mirror, 750 - 1,100 nm. Silver mirrors can also be used.</td>
		</tr>
		<tr>
			<td>Motorized Delay Stage</td>
			<td>Zaber</td>
			<td>X-DMQ12P-DE52</td>
			<td>Delay stage for fine control of the temporal overlap of the pump and the Stokes lasers. Any other motorized stage should work.</td>
		</tr>
		<tr>
			<td>Oil Immersion Condensor</td>
			<td>Nikon</td>
			<td>CSC1003</td>
			<td>1.4 NA. Other condensers with NA&#62;1.2 can be used.</td>
		</tr>
		<tr>
			<td>Oscilloscope</td>
			<td>Tektronix</td>
			<td>TDS7054</td>
			<td>Any other oscilloscope with 400 MHz bandwdith or higher should work.</td>
		</tr>
		<tr>
			<td>Phase Shifter</td>
			<td>SigaTek</td>
			<td>SF50A2</td>
			<td>For shifting the phase of the modulation frequency</td>
		</tr>
		<tr>
			<td>Photodiode</td>
			<td>Hamamatsu Corp</td>
			<td>S3994-01</td>
			<td>Silicon PIN diode with large area (10 x 10 cm2). Other diodes with large area and low capacitance can be used.</td>
		</tr>
		<tr>
			<td>Polarizing Beam Splitter</td>
			<td>Union Optic</td>
			<td>PBS9025-620-1000</td>
			<td>Broadband polarizing beamsplitter</td>
		</tr>
		<tr>
			<td>Refactive Index Database</td>
			<td></td>
			<td></td>
			<td>refractiveindex.info</td>
		</tr>
		<tr>
			<td>Retro-reflector</td>
			<td>Edmund Optics</td>
			<td>34-408</td>
			<td>BBAR Right Angle Prism. Other prisms or retroreflector can be used.</td>
		</tr>
		<tr>
			<td>RF Power Amplifier</td>
			<td>Minicircuits</td>
			<td>ZHL-1-2W+</td>
			<td>Gain Block, 5 - 500 MHz, 50 &#937;</td>
		</tr>
		<tr>
			<td>Scan Mirrors</td>
			<td>Cambridge Technologies</td>
			<td>6215H</td>
			<td>We used a 5mm mirror set with silver coating</td>
		</tr>
		<tr>
			<td>ScanImage</td>
			<td>Vidrio</td>
			<td>ScanImage Basic</td>
			<td>Laser scanning microscope control software</td>
		</tr>
		<tr>
			<td>Shortpass Filter</td>
			<td>THORLABS</td>
			<td>FESH1000</td>
			<td>25.0 mm Premium Shortpass Filter, Cut-Off Wavelength: 1,000 nm. For efficient suppression of the Stokes, two filters may be necessary.</td>
		</tr>
		<tr>
			<td>Upright Microscope</td>
			<td>Nikon</td>
			<td>Eclipse FN1</td>
			<td>Any other microscope frame can be used. If a laser scanning microscope is available, it can be used directly. Otherwise, a galvo scanner and scan lens needed to be added to the microscope.</td>
		</tr>
		<tr>
			<td>Water Immersion Objective</td>
			<td>Olympus</td>
			<td>XLPLN25XWMP2</td>
			<td>The multiphoton 25X Objective has a NA of 1.05. Other similar objectives can be used.</td>
		</tr>
	</tbody>
</table>

real-time, two-color stimulated raman scattering imaging of mouse brain for tissue diagnosis

受激拉曼散射（SRS）显微镜已成为一种用于组织诊断的强大光学成像技术。近年来，双色SRS已被证明能够提供苏木精和曙红（H&E）等效的图像，从而可以快速可靠地诊断脑癌。这种能力使令人兴奋的术中癌症诊断应用成为可能。组织的双色SRS成像可以使用皮秒或飞秒激光源完成。飞秒激光器具有支持灵活成像模式的优势，包括快速高光谱成像和实时双色SRS成像。具有啁啾激光脉冲的光谱聚焦方法通常与飞秒激光器一起使用，以实现高光谱分辨率。 
双色SRS采集可通过正交调制和锁相检测实现。脉冲啁啾、调制和表征的复杂性是该方法广泛采用的瓶颈。本文提供了一个详细的协议，以演示光谱聚焦SRS的实现和优化，以及在外延模式下小鼠脑组织的实时双色成像。该协议可用于广泛的SRS成像应用，这些应用利用了SRS的高速和光谱成像能力。

优化光谱分辨率： 通过材料的色散受色散介质（长度和材料）和波长的影响。改变色散棒长度会影响光谱分辨率和信号尺寸。这是一种给予和接受的关系，可以根据应用的不同而进行不同的权衡。视杆将光束脉冲从频率宽、时间窄到频率窄、时间宽拉伸。 图7 显示了改变棒长度对光谱分辨率的影响。 图7A 显示光谱分辨率非常差;这种设?...

Watch this Scientific Journal Video about Real-Time, Two-Color Stimulated Raman Scattering Imaging of Mouse Brain for Tissue Diagnosis at JoVE.com

Real-Time, Two-Color Stimulated Raman Scattering Imaging of Mouse Brain for Tissue Diagnosis

受激拉曼散射（SRS）显微镜是一种功能强大、无损且无标记的成像技术。一种新兴应用是刺激拉曼组织学，其中蛋白质和脂质拉曼转变处的双色SRS成像用于生成假苏木精和曙红图像。在这里，我们演示了用于组织诊断的实时双色SRS成像方案。

用于组织诊断的小鼠脑实时双色受激拉曼散射成像

Stimulated Raman scattering (SRS) microscopy has emerged as a powerful optical imaging technique for tissue diagnosis. In recent years, two-color SRS has ...

该协议将演示光谱聚焦SRS显微镜的实现和优化，以及如何将其用于实时激励拉曼组织学应用。该技术的主要优点是，一旦仪器正确对齐，就可以快速处理样品，因为SRS不需要组织处理和染色。该协议适用于其他SRS应用，而不仅限于组织学。这些应用包括小分子、药物、细胞和组织。首先为泵浦光束安装一对消色差透镜，以将激光束尺寸放大两倍作为起点。将 100 和 200 毫米的镜头放置在彼此相距约 300 毫米的位置。然后将泵浦光束对准两个透镜的中心。接下来在第二个透镜后面放置一面镜子，将光束发送到一米多远的墙壁上。使用红外卡跟踪从镜子到墙壁的光束，并检查光束的大小是否发生变化。如果光束的大小随距离而变化，则准直光束。通过安装一个二向色镜和几个转向镜进行调整，将两个激光束组合在一起。通过监测二向色镜后两个不同位置的光束，优化泵和斯托克斯的空间重叠，这些光束相距约一米。迭代调整转向镜，然后调整二向色镜，使斯托克斯光束与泵光束对齐。当扫描镜处于停放位置时，通过调整一对转向镜，确保将组合光束发送到激光扫描显微镜扫描镜的中心。在聚光镜之后，使用另一对焦距分别为100毫米和30毫米的透镜，将传输的光束传递到光电二极管上，确保两个光束都包含在光电二极管内。然后安装两个低通滤波器以阻挡调制的斯托克斯光束。在斯托克斯光束路径中放置一个光束采样器，以拾取10%的光束并将其发送到快速光电二极管以检测80兆赫兹脉冲序列。取扇出缓冲器的一个输出，并用带通滤波器对其进行滤波，以获得20兆赫兹的正弦波。然后使用RF衰减器将输出峰峰值电压调节至约500毫伏。将得到的输出发送到移相器，从而允许使用电压源对RF相位进行微调。将此输出发送到RF功率放大器，并将放大器的输出连接到EOM。在疏通斯托克斯光束后，通过在光束路径中放置光电二极管来优化第一个EOM的调制深度。调整EOM电压和四分之一波片，直到调制深度看起来令人满意。在二向色镜后放置光电二极管以检测激光束。首先阻挡斯托克斯光束，然后放大示波器上的一个泵脉冲峰值。放置垂直光标，用示波器标记此峰值的时间位置。现在阻挡泵梁，并疏通斯托克斯梁。转换延迟级，将示波器上的峰值位置与上一步中的标记位置临时匹配。通过计算匹配两束光束所需的延迟距离，然后拉长较快光束的光束路径或缩短较慢光束的光束路径。接下来，用DMSO和双面胶带作为垫片准备显微镜载玻片样品，以将样品固定在载玻片和盖玻片之间。将样品放在显微镜上，盖玻片面朝向显微镜物镜，并在明场照明下观察I片中的样品。在玻璃胶带界面处的顶层和底层气泡处找到样品的焦点，然后将焦点移动到胶带的两层之间。接下来将可调谐光束输出设置为798纳米。根据聚光镜的光通量，将目标焦点处的泵浦和斯托克斯光束的光功率调整为约40毫瓦。然后在MATLAB中打开扫描图像，然后单击标有焦点的按钮开始扫描。在电流扫描器之前调整转向镜，将直流信号居中放在通道一个显示屏上。移动电动延迟级，并密切观察通道二显示屏上显示的锁相输出。最后调整时间延迟以最大化交流信号强度。调整二向色镜，使 SRS 信号在交流通道上居中。然后调整锁相放大器的相位，使信号最大化。将样品载玻片安装到显微镜上，并在样品聚焦时将两束光束的功率调整到每个光束约40毫瓦后，如前所述。从 MATLAB 打开扫描图像。然后通过扫描对应于DMSO的2， 913反厘米拉曼峰的延迟级来找到最大SRS信号。获取对应于DMSO的2， 913反厘米拉曼峰的SRS图像。在 ImageJ 中打开图像，然后选择帧中心的一个小区域。使用测量函数可以计算所选区域中值的均值和标准差。对于频率访问校准，请保存高光谱扫描，延迟级范围覆盖DMSO的2，913和2，994反厘米拉曼峰。然后保存与高光谱数据集相对应的载物台位置。对载物台位置和拉曼位移在 2、913 和 2、994 反厘米处执行线性回归。使用线性回归方程，将延迟位置转换为相应的拉曼频率。为了校准光谱分辨率，根据先前的位置估计载物台位置，由于插入棒而增加光程长度。重新对齐光束空间重叠，因为添加玻璃棒时光束的轻微偏差。在第一个EOM之后，在浸泡光束路径中安装一个偏振分束器，一个四分之一波板和第二个EOM。拔下第二个 EOM 的信号输入，然后将信号输入插入第一个 EOM，然后将其打开。通过将光束发送到第一个EOM，将斯托克斯光束调制为20兆赫兹。调整第一个EOM的倾斜度和位置，以确保光束通过EOM晶体居中。用双面胶带，显微镜载玻片和盖玻片制备组织载玻片样品。将样品放在显微镜上，盖玻片面朝向显微镜物镜。对于落射模式SRS成像，在光束进入显微镜之前安装一个半波板，以改变进入显微镜的光束的偏振。在物镜上方放置一个偏振分束器，以使去极化的背面反射光束到达探测器。接下来，使用75毫米消色差透镜和30毫米非球面透镜将背散射光子从物镜的后孔径传递到光电探测器。安装探测器以收集偏振分束器所引导的背散射光。然后安装一个滤波器，以阻止调制光束进入探测器。改变棒长度会影响光谱分辨率。当不使用玻璃啁啾棒时，DMSO的两个拉曼峰根本无法分辨。玻璃啁啾棒数量的增加开始在令人满意的点上解析两个峰值。匹配的啁啾声可解析两个峰值，并可用于根据频率校准载物台位置。用于对DMSO光谱进行成像的正交偏振的两个时间延迟脉冲序列显示了具有可接受调制深度和时间分离的SRS激励之间的时间延迟。相反，较差的双色SRS相移会产生倒置或负峰。此处显示了在2，850和2，930反向厘米的离体小鼠脑组织处的实时双色SRS成像。原始脂质和蛋白质图像被颜色编码以产生描绘脂质和蛋白质贡献的单一图像。还进行了假苏木精和曙红复色，以模仿苏木精和曙红染色用于病理学应用。空间时间重叠和空间分辨率优化是SRS空间聚焦方法最重要的步骤。该方法一般适用于其他泵浦探针显微镜实验，如瞬态吸收显微镜。该方法还允许对细胞和组织中的非荧光分子进行成像。这里介绍的方法加快了图像采集时间，以便将来在临床上翻译受激拉曼组织学。

Research

JoVE Journal

Bioengineering

Non-contact, Label-free Monitoring of Cells and Extracellular Matrix using Raman Spectroscopy

非接触，无标签使用拉曼光谱研究细胞和细胞外基质的监测

Non-destructive, non-contact and label-free technologies to monitor cell and tissue cultures are needed in the field of biomedical research.1-5 However, ...

科研

生物工程

Universal Hand-held Three-dimensional Optoacoustic Imaging Probe for Deep Tissue Human Angiography and Functional Preclinical Studies in Real Time

通用型手持式三维光声成像探测深部组织人力造影和功能的临床前研究中实时

The exclusive combination of high optical contrast and excellent spatial resolution makes optoacoustics (photoacoustics) ideal for simultaneously ...

Using Cell-substrate Impedance and Live Cell Imaging to Measure Real-time Changes in Cellular Adhesion and De-adhesion Induced by Matrix Modification

使用Cell-基板阻抗和活细胞成像，以衡量矩阵修改诱导实时变化的细胞粘附和去粘附

Cell-matrix adhesion plays a key role in controlling cell morphology and signaling. Stimuli that disrupt cell-matrix adhesion (e.g., myeloperoxidase and ...

Real-time Monitoring of High Intensity Focused Ultrasound (HIFU) Ablation of In Vitro Canine Livers Using Harmonic Motion Imaging for Focused Ultrasound (HMIFU)

Real-time Monitoring of High Intensity Focused Ultrasound HIFU Ablation of In Vitro Canine Livers Using Harmonic Motion Imaging for Focused Ultrasound HMIFU

高强度的实时监控聚焦超声（HIFU）消融<em&gt;体外</em&gt;使用谐运动成像的聚焦超声犬肝脏（HMIFU）

Harmonic Motion Imaging for Focused Ultrasound (HMIFU) is a technique that can perform and monitor high-intensity focused ultrasound (HIFU) ablation. An ...

Hand-held Clinical Photoacoustic Imaging System for Real-time Non-invasive Small Animal Imaging

手持式实时非侵入性小动物成像的临床光声成像系统

Translation of photoacoustic imaging into the clinic is a major challenge. Handheld real-time clinical photoacoustic imaging systems are very rare. Here, ...

A Protocol for Real-time 3D Single Particle Tracking

一种实时3D 单粒子跟踪协议

Real-time three-dimensional single particle tracking (RT-3D-SPT) has the potential to shed light on fast, 3D processes in cellular systems. Although ...

In Situ Microscopy for Real-time Determination of Single-cell Morphology in Bioprocesses

In Situ Microscopy for Real-time Determination of Single-cell Morphology in Bioprocesses

在原位生物过程单细胞形态实时测定的显微镜

In situ monitoring in microbial bioprocesses is mostly restricted to chemical and physical properties of the medium (e.g.,pH value and the dissolved ...

In Vivo Two-Color 2-Photon Imaging of Genetically-Tagged Reporter Cells in the Skin

在 Vivo 双色 2 光子成像中,基因标记报告器细胞在皮肤中

Fibroblasts are mesenchymal cells that change their morphology upon activation, ultimately influencing the microenvironment of the tissue they are located ...

Real-Time Intravital Multiphoton Microscopy to Visualize Focused Ultrasound and Microbubble Treatments to Increase Blood-Brain Barrier Permeability

实时活体内多光子显微镜可可视化聚焦超声和微气泡处理，以提高血脑屏障通透性

The blood-brain barrier (BBB) is a key challenge for the successful delivery of drugs to the brain. Ultrasound exposure in the presence of microbubbles ...

In vivo Imaging of Biological Tissues with Combined Two-Photon Fluorescence and Stimulated Raman Scattering Microscopy

In vivo Imaging of Biological Tissues with Combined Two-Photon Fluorescence and Stimulated Raman Scattering Microscopy

体内 使用双光子荧光和受激拉曼散射显微镜对生物组织进行成像

Stimulated Raman scattering (SRS) microscopy enables label-free imaging of the biological tissues in its natural microenvironment based on intrinsic ...