我们想感谢曼弗雷德Kriechbaum Hecus XRS和在奥地利格拉茨的奥地利科学院生物物理研究所和纳米系统研究。 LL和XW部分由美国能源部支持下，NERI-C号DE-FG07-07ID14889奖，美国核管理委员会，根据奖励编号：NRC-38-08-950。部分由美国能源部也支持SWAXS仪器，在裁决号DE-NE0000325。

1。的样品的制备<ol><li>使用一根针，以除去一些样品从样品容器。 </li><li>使用的针，以填补在毛细管（最大直径为2.2毫米）用样品。的毛细管必须填写从底部2和3厘米之间。 </li><li>关闭的毛细血管，熔蜡器在前端。 </li><li>拧下从系统的真空样品架。 </li><li>以毛细管融合的结束（蜡年底），将未熔的样品架。 </li><li>持有人将到系统中，螺杆的地方。 </li></ol> *固体样品（包括粉末样品），可以直接放置在样品架（没有毛细必要），而液体样品必须被放置在一个毛细管。 启动SWAXS机 2。源冷启动程序<ol><li>在推动安全快门按钮，关闭快门。 </li><li>切换主电源按绿色按钮上的“ON”。 </li><li>验证紧急“关闭”按钮，在延伸的位置。 </li><li>按下绿色的按钮切换主电源。 </li><li>确认的联锁LED灯是绿色，表示所有的互锁确定的。 </li><li>等待在触摸屏上加载。它加载后，按“R6”菜单上的。 </li><li>关闭待机键，“ON”的位置。 </li><li>转动透视关键的“ON”位置。红色的X-射线灯应点亮。 </li><li>等待读取待机的水平（30千伏及0.4毫安）的触摸屏。 </li><li>将备安全的关键在“OFF”的位置。按下“启动循环”的按钮，在触摸屏的底部。 </li><li>等待在触摸屏上读额定功率（50千伏和1 mA）。如果使用不同的功率电平，进入配置屏幕，在触摸屏上按“R4”，并输入所需的设置。 </li></ol> 3。冷水机程序<ol><li>打开电源SWITCH在温度控制面板上的“ON”位置。的控制灯和LED温度显示器会亮起。 </li><li>打开电源开关至“ON”的位置上冷水机组。 </li><li>等待，直到温度显示屏显示“OFF”。这是待机模式。 </li><li>按下并按住ENTER按钮（返回符号）约4秒或直到显示的温度指示的实际温度。 </li><li>要改变温度，按向上或向下的箭头。将会显示在温度显示为约8秒的设定值之前，它会返回到的实际值。 </li><li>一旦所需的设定值显示，按ENTER键。这将存储该值。 </li><li>等待，直到实际温度达到所需的设定值。 </li></ol> 注意：如果在任何时候出现错误“E 01”显示的温度显示，按照冷水机组停机指令，填充浇注罐过滤的纯净水洗澡单位l，然后执行冷水机组一次启动程序。 4。关闭冷水机组<ol><li>按“输入”键约4秒。 </li><li>打开电源开关到“OFF”的位置。 </li></ol> 5。打开真空<ol><li>确保真空门被固定就位。 </li><li>真空1和2旋钮转到“ON”位置。 </li><li>等待，直到VAP5真空表的读数小于1.5毫巴的真空度。 </li></ol> 6。检测器的系统设置<ol><li>要设置的气体压力，验证主压力表的减压阀是在至少10巴。 </li><li>打开主阀。 </li><li>慢慢地打开，直到压力达到工作压力阀的工作压力表的8栏。 </li><li>打开第二个主阀</li><li>调整气体的流动，打开主配压阀，气体控制面板上通过转动旋钮到垂直位置。 </li><li>调整流量针型阀，直到压力表读数率约8巴。 </li><li>打开主电源开关至“ON”的位置。 LED灯应点亮。 </li><li>要调整高电压，高电压激活的开关旋转到“ON”的位置。 LED灯应点亮。 </li><li>慢慢转动约3.5KV电压控制旋钮，直至达到压力表上。不要超过4KV。 </li></ol> 7。校准<ol><li>以上的实验步骤进行与样品的已知峰。 </li><li> ASA 3.3用于获得图5峰的强度与通道。 </li><li>进入功能表→“选项”→输入通道和相应的强度。 </li><li> ，转到ASA3，“TPF”选项卡。 </li><li>更改过滤器，左上方1毫米镍（束过滤器）。 </li><li>设置位置32,000（28,000至32,000范围内，大约28000名的临界区）→位置，确保真空度低于5毫巴，确保检测是原因丁1K-10K之间。 </li><li>运行，持续10秒，每秒约52计数。 </li><li>更改能源窗，（或只与样品，不包括过滤器的情况下测量的能量窗）。将最后的奔跑，持续10秒。 </li><li>查找的位置的主光束（例如信道233）。 </li><li>对于其他的运行，更改过滤器再次到2毫米钨（W，梁挡块），从30000开始。 </li><li>查找其他所有的样品峰的位置。 </li><li>使用ImageJ的宏的软件校准SAXS -从强度与信道转换的强度与q（下或d间距）（ 图1）。 </li><li>使用ImageJ的宏软件校准WAXS - ，从强度与信道转换的强度与q（下或d间距）（ 图2）。 </li></ol> 8。软件程序<ol><li>使用该软件ASA 3.3，收集实时数据，实时数据“→”和TPF选项卡→“保存文件。 </li><li>对于EasySWAXS，点击“设备设置”选项卡。 </li><li>输入的“a”，λ，和d的值，以及重心。 </li><li>选择点瞄准。 </li><li>选择球状粒子类型（除非它是公知的是扁平状颗粒的杆）。 </li><li>按一下的吉尼尔情节“选项卡上。的I和Q 2的图形将被显示出来。 </li><li>拖动垂直线包围的部分近似直线的斜率。 </li><li>在屏幕的底部，R值会被显示。这是一个验证的要求。 </li><li>继续拖动垂直线更接近在一起，直到验证值是1和2之间。这是主观的。的R值，或回转半径，是一个估计。 </li></ol> 9。来源关机程序<ol><li>验证的安全性和快速的快门关闭。 </li><li>关闭待机键，“ON”的位置。 </li><li>等待所述触摸屏来读取备用水平。 </li><li>按R5的touchscreen。 </li><li>降低电流到0 A. </li><li>的电压降低到0 A。 </li><li>转动透视键的“OFF”位置。 </li><li>通过按下红色的关闭按钮，切换主电源“OFF”。 </li></ol>

<ol>
	<li>Bernad&#243;, P., Blackledge, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structural+biology:+Proteins+in+dynamic+equilibrium.">Structural biology: Proteins in dynamic equilibrium.</a> Nature. 468, 1046-1048 (2010).</li><li>Zhang, F., Skoda, M. W. A., Jacobs, R. M. J., Martin, R. A., Martin, C. M., Schreiber, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Protein+Interactions+Studied+by+SAXS:+Effect+of+Ionic+Strength+and+Protein+Concentration+for+BSA+in+Aqueous+Solutions.">Protein Interactions Studied by SAXS: Effect of Ionic Strength and Protein Concentration for BSA in Aqueous Solutions.</a> J. Phys. Chem. B. 111, 251-259 (2007).</li><li>Maranas, J. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+environment+on+local+dynamics+of+macromolecules.">The effect of environment on local dynamics of macromolecules.</a> Current Opinion in Colloid &amp; Interface Science. 12, 29-42 (2007).</li><li>Stribeck, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> X-Ray Scattering of Soft Matter. , (2007).</li><li>Mertens, H. D., Svergun, D. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structural+characterization+of+proteins+and+complexes+using+small-angle+X-ray+solution+scattering.">Structural characterization of proteins and complexes using small-angle X-ray solution scattering.</a> J. Struct. Biol. 172 (1), 128 (2010).</li><li>Svergun, D. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Small-angle+X-ray+and+neutron+scattering+as+a+tool+for+structural+systems+biology.">Small-angle X-ray and neutron scattering as a tool for structural systems biology.</a> Biol. Chem. 391 (7), 737 (2010).</li><li>Putnam, C. D., Hammel, M., Hura, G. L., Tainer, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=X-ray+solution+scattering+(SAXS)+combined+with+crystallography+and+computation:+defining+accurate+macromolecular+structures,+conformations+and+assemblies+in+solution.">X-ray solution scattering (SAXS) combined with crystallography and computation: defining accurate macromolecular structures, conformations and assemblies in solution.</a> Quat. Rev. Biophys. 40, 191-285 (2007).</li><li>Bonini, M., Fratini, E., Baglioni, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=SAXS+study+of+chain-like+structures+formed+by+magnetic+nanoparticles.">SAXS study of chain-like structures formed by magnetic nanoparticles.</a> Materials Science &amp; Engineering C-Biomimetic and Supramolecular Systems. 27 (5-8), 1377-1381 (2007).</li><li>Falletta, E., Ridi, F., Fratini, E., Vannucci, C., Canton, P., Bianchi, S., Castelvetro, V., Baglioni, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+tri-block+copolymer+templated+synthesis+of+gold+nanostructures.">A tri-block copolymer templated synthesis of gold nanostructures.</a> Journal of Colloid and Interface Science. 357 (1), 88-94 (2011).</li><li>Glatter, O., Scherf, G., Schillen, K., Brown, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+a+Poly(ethylene+oxide)+Poly(propylene+oxide)+Triblock+Copolymer+(EO(27)-PO39-EO(27))+in+Aqueous-Solution.">Characterization of a Poly(ethylene oxide) Poly(propylene oxide) Triblock Copolymer (EO(27)-PO39-EO(27)) in Aqueous-Solution.</a> Macromolecules. 27 (21), 6046-6054 (1994).</li><li>Mittelbach, R., Glatter, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+structure+analysis+of+small-angle+scattering+data+from+polydisperse+colloidal+particles.">Direct structure analysis of small-angle scattering data from polydisperse colloidal particles.</a> Journal of Applied Crystallography. 31, 600-608 (1998).</li></ol>

没有利益冲突的声明。

比较程序的SWAXS系统的允许众多变量来确定实验分析。从分析中获得的参数，这些参数可以被用于不同的目的，根据样品和实验设置。 SAXS提供纳米尺度的对象的大小和形状有关下列内容的信息，而WAXS重点上的原子和微观尺度的结构（ 如分子晶格，晶胞尺寸对称性）。更具体地，在稀溶液中的颗粒，小角X射线散射可以研究回转，粒子大小和形状的半径;用于高密度的样品，小角X射线散射可?...

<table border="1"><tbody><tr><td> 产品名称 </td><td> 公司 </td></tr><tr><td>该系统3小型和广角X射线散射（SWAXS）相机</td><td> Hecus XRS和IBN， 奥地利格拉茨</td></tr><tr><td> GNOM </td><td> ATSAS 2.3包D. Svergun EMBL-汉堡</td></tr></tbody></table>

small and wide angle x-ray scattering studies of biological macromolecules in solution

在本文中，小型和广角X射线散射（SWAXS）分析大分子通过实验证明。 SWAXS是一种技术，其中X-射线被弹性散射在小角度（通常为0.1 - 5°）和宽角度（通常&gt; 5°）nm的范围中的由非均匀样品。这种技术提供的信息有关的形状，尺寸和分布的大分子，部分有序材料，孔径大小，和表面对体积之比的特征距离。小角度X射线散射（SAXS）是能够提供在1和200nm之间的大分子结构信息，而可以解决广角X射线散射（WAXS）更小布喇0.33 nm和0.49 nm的间距之间的样品的基础上具体的系统设置和检测器。的间距从布拉格定律确定，是依赖于波长和入射角。 在一个SWAXS实验，材料可以是固体或液体，并可能含有固体，液体或气体的域（所谓的粒子）的同一个或另一个的材料中的任何组合。 SWAXS的应用是非常广泛的，包括所有的类型：金属，复合材料，水泥，油，聚合物，塑料，蛋白质，食品和药品的胶体。对于固体样品的厚度被限制为约5毫米。 实验室为基础的SWAXS仪器的使用本文中详细介绍。可用的软件（ 例如 ，GNOM ATSAS 2.3包由D. Svergun的EMBL-的汉堡和EasySWAXS软件的）的SWAXS系统，可以进行的实验，以确定某些参数给定的样本。生物大分子实验的一个例子，是一种水基的水性缓冲液中，可以选择并通过许多方法制备的2％（重量）中溶菌酶的分析。样品制备遵循以下准则编制的示例部分。通过SWAXS实验，的溶菌酶的重要的结构参数， 例如 ，可以分析的回转半径。

小角X射线散射和WAXS完全可以提供结构信息的样品通过以下参数：回转，颗粒的大小和形状，解决方案的结构因子，具体的内表面和孔径大小，晶格的类型和尺寸，和电子密度1的半径。也可应用于小角X射线散射和WAXS研究蛋白质动力学2。 的结构信息SWAXS实验得到的实验检测到的光谱和该系统的计算结果进行比较。的计算结果，计算在一个合理的有效电位<sub...

Watch this Scientific Journal Video about Small and Wide Angle X-Ray Scattering Studies of Biological Macromolecules in Solution at JoVE.com

Small and Wide Angle X-Ray Scattering Studies of Biological Macromolecules in Solution | Bioengineering | Video

Small and Wide Angle X-Ray Scattering Studies of Biological Macromolecules in Solution

小型和广角X-射线散射（SWAXS）过程的演示已经成为有助于在研究生物大分子。通过使用特定的角度的方法和准备的仪器和程序，从SWAXS的实验数据显示大分子的原子和纳米尺度的表征。

小型和广角X-射线散射研究生物大分子的解决方案

In this paper, Small and Wide Angle X-ray Scattering (SWAXS) analysis of macromolecules is demonstrated through experimentation. SWAXS is a technique ...

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17.9K 次观看.  Rensselaer Polytechnic Institute. 小型和广角X-射线散射（SWAXS）过程的演示已经成为有助于在研究生物大分子。通过使用特定的角度的方法和准备的仪器和程序，从SWAXS的实验数据显示大分子的原子和纳米尺度的表征。

视频: Small and Wide Angle X-Ray Scattering Studies of Biological Macromolecules in Solution

Fabrication of Electrochemical-DNA Biosensors for the Reagentless Detection of Nucleic Acids, Proteins and Small Molecules

As medicine is currently practiced, doctors send specimens to a central laboratory for testing and thus must wait hours or days to 
receive the results. Many patients would be better served by rapid, bedside tests. To this end our laboratory and others have developed a versatile, reagentless 
biosensor platform that supports the quantitative, reagentless, electrochemical detection of nucleic acids (DNA, RNA), proteins (including antibodies) and small 
molecules analytes directly in unprocessed clinical and environmental samples. In this video, we demonstrate the preparation and use of several biosensors in this 
"E-DNA" class. In particular, we fabricate and demonstrate sensors for the detection of a target DNA sequence in a polymerase chain reaction mixture, an HIV-specific antibody and the drug cocaine. The preparation procedure requires only three hours of hands-on effort followed by an overnight incubation, and their use requires only minutes.

"E-DNA" sensors, reagentless, electrochemical biosensors that perform well even when challenged directly in blood and other complex matrices, have been adapted to the detection of a wide range of nucleic acid, protein and small molecule analytes. Here we present a general procedure for the fabrication and use of such sensors.

无试剂检测核酸，蛋白质和小分子的电化学DNA生物传感器的制备

As medicine is currently practiced, doctors send specimens to a central laboratory for testing and thus must wait hours or days to 
receive the results. ...

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In situ TEM of Biological Assemblies in Liquid

Researchers regularly use Transmission Electron Microscopes (TEMs) to examine biological entities and to assess new materials. Here, we describe an additional application for these instruments- viewing viral assemblies in a liquid environment. This exciting and novel method of visualizing biological structures utilizes a recently developed microfluidic-based specimen holder. Our video article demonstrates how to assemble and use a microfluidic holder to image liquid specimens within a TEM. In particular, we use simian rotavirus double-layered particles (DLPs) as our model system. We also describe steps to coat the surface of the liquid chamber with affinity biofilms that tether DLPs to the viewing window. This permits us to image assemblies in a manner that is suitable for 3D structure determination. Thus, we present a first glimpse of subviral particles in a native liquid environment.

In situ TEM of Biological Assemblies in Liquid

Here we describe a procedure to image viral complexes in liquid at nanometer resolution using a transmission electron microscope.

就地 液体生物组件的 TEM

Researchers regularly use Transmission Electron Microscopes (TEMs) to examine biological entities and to assess new materials. Here, we describe an ...

Characterization Of Multi-layered Fish Scales (Atractosteus spatula) Using Nanoindentation, X-ray CT, FTIR, and SEM

The hierarchical architecture of protective biological materials such as mineralized fish scales, gastropod shells, ram&#8217;s horn, antlers, and turtle shells provides unique design principles with potentials for guiding the design of protective materials and systems in the future. Understanding the structure-property relationships for these material systems at the microscale and nanoscale where failure initiates is essential. Currently, experimental techniques such as nanoindentation, X-ray CT, and SEM provide researchers with a way to correlate the mechanical behavior with hierarchical microstructures of these material systems1-6. However, a well-defined standard procedure for specimen preparation of mineralized biomaterials is not currently available. In this study, the methods for probing spatially correlated chemical, structural, and mechanical properties of the multilayered scale of A. spatula using nanoindentation, FTIR, SEM, with energy-dispersive X-ray (EDX) microanalysis, and X-ray CT are presented.

Characterization Of Multi-layered Fish Scales Atractosteus spatula Using Nanoindentation, X-ray CT, FTIR, and SEM

This paper presents the methods used for probing spatially correlated chemical, structural, and mechanical properties of the multilayered scale of Atractosteus spatula (A. spatula) using nanoindentation, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and X-ray computed tomography (X-ray CT). The experimental results have been used to investigate the design principles of protective biological materials.

表征多层鱼鳞（中<em&gt; Atractosteus锅铲</em&gt;）基于纳米压痕技术，X射线CT，红外光谱和SEM

The hierarchical architecture of protective biological materials such as mineralized fish scales, gastropod shells, ram&#8217;s horn, antlers, and turtle ...

Studying Soft-matter and Biological Systems over a Wide Length-scale from Nanometer and Micrometer Sizes at the Small-angle Neutron Diffractometer KWS-2

The KWS-2 SANS diffractometer is dedicated to the investigation of soft matter and biophysical systems covering a wide length scale, from nm to &#181;m. The instrument is optimized for the exploration of the wide momentum transfer Q range between 1x10-4 and 0.5 &#197;-1 by combining classical pinhole, focusing (with lenses), and time-of-flight (with chopper) methods, while simultaneously providing high-neutron intensities with an adjustable resolution. Because of its ability to adjust the intensity and the resolution within wide limits during the experiment, combined with the possibility to equip specific sample environments and ancillary devices, the KWS-2 shows a high versatility in addressing the broad range of structural and morphological studies in the field. Equilibrium structures can be studied in static measurements, while dynamic and kinetic processes can be investigated over time scales between minutes to tens of milliseconds with time-resolved approaches. Typical systems that are investigated with the KWS-2 cover the range from complex, hierarchical systems that exhibit multiple structural levels (e.g., gels, networks, or macro-aggregates) to small and poorly-scattering systems (e.g., single polymers or proteins in solution). The recent upgrade of the detection system, which enables the detection of count rates in the MHz range, opens new opportunities to study even very small biological morphologies in buffer solution with weak scattering signals close to the buffer scattering level at high Q.
In this paper, we provide a protocol to investigate samples with characteristic size levels spanning a wide length scale and exhibiting ordering in the mesoscale structure using KWS-2. We present in detail how to use the multiple working modes that are offered by the instrument and the level of performance that is achieved.

Here, we present a protocol to investigate soft matter and biophysical systems over a wide mesoscopic length scale, from nm to &#181;m that involves the use of the KWS-2 SANS diffractometer at high intensities and an adjustable resolution.

在小角度中子衍射仪KWS-2研究软物质和生物系统在广泛的长度尺度从纳米，微米尺寸

The KWS-2 SANS diffractometer is dedicated to the investigation of soft matter and biophysical systems covering a wide length scale, from nm to &#181;m. ...

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 ...

A Novel Technique for Generating and Observing Chemiluminescence in a Biological Setting

Intraoperative imaging techniques have the potential to make surgical interventions safer and more effective; for these reasons, such techniques are quickly moving into the operating room. Here, we present a new approach that utilizes a technique not yet explored for intraoperative imaging: chemiluminescent imaging. This method employs a ruthenium-based chemiluminescent reporter along with a custom-built nebulizing system to produce ex vivo or in vivo images with high signal-to-noise ratios. The ruthenium-based reporter produces light following exposure to an aqueous oxidizing solution and re-reduction within the surrounding tissue. This method has allowed us to detect reporter concentrations as low as 6.9 pmol/cm2. In this work, we present a visual guide to our proof-of-concept in vivo studies involving subdermal and intravenous injections in mice. The results suggest that this technology is a promising candidate for further preclinical research and might ultimately become a useful tool in the operating room.

This protocol describes a new intraoperative imaging technique that uses a ruthenium complex as a source of chemiluminescent light emission, thereby producing high signal-to-noise ratios during in vivo imaging. Intraoperative imaging is an expanding field that could revolutionize the way that surgical procedures are performed.

在生物环境的新技术的产生和观测化学发光

Intraoperative imaging techniques have the potential to make surgical interventions safer and more effective; for these reasons, such techniques are ...

Patterning Bioactive Proteins or Peptides on Hydrogel Using Photochemistry for Biological Applications

There are many biological stimuli that can influence cell behavior and stem cell differentiation. General cell culture approaches rely on soluble factors within the medium to control cell behavior. However, soluble additions cannot mimic certain signaling motifs, such as matrix-bound growth factors, cell-cell signaling, and spatial biochemical cues, which are common influences on cells. Furthermore, biophysical properties of the matrix, such as substrate stiffness, play important roles in cell fate, which is not easily manipulated using conventional cell culturing practices. In this method, we describe a straightforward protocol to provide patterned bioactive proteins on synthetic polyethylene glycol (PEG) hydrogels using photochemistry. This platform allows for the independent control of substrate stiffness and spatial biochemical cues. These hydrogels can achieve a large range of physiologically relevant stiffness values. Additionally, the surfaces of these hydrogels can be photopatterned with bioactive peptides or proteins via thiol-ene click chemistry reactions. These methods have been optimized to retain protein function after surface immobilization. This is a versatile protocol that can be applied to any protein or peptide of interest to create a variety of patterns. Finally, cells seeded onto the surfaces of these bioactive hydrogels can be monitored over time as they respond to spatially specific signals.

In this method, we use photopolymerization and click chemistry techniques to create protein or peptide patterns on the surface of polyethylene glycol (PEG) hydrogels, providing immobilized bioactive signals for the study of cellular responses in vitro.

生物活性蛋白或多肽在水凝胶上的应用

There are many biological stimuli that can influence cell behavior and stem cell differentiation. General cell culture approaches rely on soluble factors ...

Development of Microfluidic Devices to Study the Elongation Capability of Tip-growing Plant Cells in Extremely Small Spaces

In vivo, tip-growing plant cells need to overcome a series of physical barriers; however, researchers lack the methodology to visualize cellular behavior in such restrictive conditions. To address this issue, we have developed growth chambers for tip-growing plant cells that contain a series of narrow, micro-fabricated gaps (~1 &#181;m) in a poly-dimethylsiloxane (PDMS) substrate. This transparent material allows the user to monitor tip elongation processes in individual cells during microgap penetration by time-lapse imaging. Using this experimental platform, we observed morphological changes in pollen tubes as they penetrated the microgap. We captured the dynamic changes in the shape of a fluorescently labeled vegetative nucleus and sperm cells in a pollen tube during this process. Furthermore, we demonstrated the capability of root hairs and moss protonemata to penetrate the 1 &#181;m gap. This in vitro platform can be used to study how individual cells respond to physically constrained spaces and may provide insights into tip-growth mechanisms.

We describe a method to investigate the capability of tip-growing plant cells, including pollen tubes, root hairs, and moss protonemata, to elongate through extremely narrow gaps (~1 &#181;m) in a microfluidic device.

微流控装置在极小空间中研究尖端生长植物细胞的伸长能力

In vivo, tip-growing plant cells need to overcome a series of physical barriers; however, researchers lack the methodology to visualize cellular behavior ...

Using Nanoplasmon-Enhanced Scattering and Low-Magnification Microscope Imaging to Quantify Tumor-Derived Exosomes

Infected or malignant cells frequently secrete more exosomes, leading to elevated levels of disease-associated exosomes in the circulation. These exosomes have the potential to serve as biomarkers for disease diagnosis and to monitor disease progression and treatment response. However, most exosome analysis procedures require exosome isolation and purification steps, which are usually time-consuming and labor-intensive, and thus of limited utility in clinical settings. This report describes a rapid procedure to analyze specific biomarkers on the outer membrane of exosomes without requiring separate isolation and purification steps. In this method, exosomes are captured on the surface of a slide by exosome-specific antibodies and then hybridized with nanoparticle-conjugated antibody probes specific to a disease. After hybridization, the abundance of the target exosome population is determined by analyzing low-magnification dark-field microscope (LMDFM) images of the bound nanoparticles. This approach can be easily adopted for research and clinical use to analyze membrane-associated exosome biomarkers linked to disease.

Clinical translation of exosome-derived biomarkers for diseased and malignant cells is hindered by the lack of rapid and accurate quantification methods. This report describes the use of low-magnification dark-field microscope images to quantify specific exosome subtypes in small volume serum or plasma samples.

纳米等离子体增强散射和低放大显微镜成像对肿瘤衍生外质体的定量

Infected or malignant cells frequently secrete more exosomes, leading to elevated levels of disease-associated exosomes in the circulation. These exosomes ...

Use of Micro X-ray Computed Tomography with Phosphotungstic Acid Preparation to Visualize Human Fibromuscular Tissue

Manual dissection and histological observation are common methods used to investigate human tissues. However, manual dissection can damage delicate structures&#160;while processing and histological observation provide limited information through cross-sectional imaging. Micro X-ray computed tomography (microCT) is an effective tool for obtaining three-dimensional information without damaging specimens. However, it shows limited efficiency in differentiating soft tissue parts. Use of contrast-enhancing agents, like phosphotungstic acid (PTA), can solve this problem by improving soft tissue contrast. We implemented microCT with PTA to investigate the human orbicularis retaining ligament (ORL), which is a delicate structure in the orbit area. In this method, harvested specimens are fixed in formalin, dehydrated in serial ethanol solutions, and stained with a PTA solution. After staining, microCT scanning, 3D reconstruction, and analysis are performed. Skin, ligaments, and muscles can be clearly visualized using this method. The specimen size and duration of staining are essential features of the method. The suitable specimen thickness was about 5&#8211;7 mm, above which the process was slowed, and the optimum duration was 5&#8211;7 days, below which an empty hole in the central area occasionally occurred. To maintain the location and direction of small pieces during cutting, sewing on the same region of each part is recommended. Furthermore, preliminary analyses of the anatomical structure are needed to correctly identify each piece. Parafilm can be used to prevent drying, but care should be taken to prevent specimen distortion. Our multidirectional observation showed that the ORL is composed of a multilayered meshwork of continuous plates, rather than thread-like fibers, as reported previously. These results suggest that microCT scanning with PTA is useful for examining specific compartments within complex structures of human tissue. It may be helpful in the analyses of cancer tissues, nerve tissues, and various organs, like the heart and liver.

Micro X-ray computed tomography is effective in obtaining three-dimensional information from undamaged human specimens but has limited success in observing soft tissues. The use of phosphotungstic acid contrast agent can resolve this issue. We implemented this contrast agent to examine human delicate fibromuscular tissues (the orbicularis retaining ligament).

使用微X射线计算机断层扫描与磷酸制备可视化人类纤维肌组织

Manual dissection and histological observation are common methods used to investigate human tissues. However, manual dissection can damage delicate ...