31301950和31671288:这个项目是由中国国家自然科学基金委员会（NSFC）的支持。

目前的方法已经建立和验证，收获和存储超过1000个肌肉样品在我们的实验室组织学染色。所有涉及动物护理和使用程序，其次是中国农业部制定的准则。 1.设备的样品采集<ol><li>标签上的每个低温小瓶样品的身份。 注意:低温小瓶是专门设计的新鲜冷冻的组织样品的冷冻切片过程（ 图1A）。将小瓶在模具工厂（ 图1C）由聚丙烯制成。 </li><li>获得以下设备:在合适的液氮罐液氮，安全眼镜或面罩，冰柜手套，10厘米钳子，25厘米镊子，聚苯乙烯泡沫塑料冷却器（内部尺寸:20厘米长×12厘米宽X13.5厘米高;外部尺寸:24厘米长×16厘米宽×15厘米高），塑料薄膜（2.5厘米长×0.8厘米宽×0.1毫米厚），手术刀和A4 PVC结合盖板（21厘米×29.5厘米）（ 图1B）。 </li></ol> 2.肌肉样品的制备<ol><li>填充提前样品收集的液态氮5分钟的泡沫塑料冷却器。 注:液氮的大柱是必需的，因为液态氮的一部分沸腾远离而成为气体时新鲜样品触摸它。为了降低液态氮的转移频率来补充损失，适当尺寸的泡沫聚苯乙烯冷却器必须事先根据样本的数量获得的。 </li><li>一旦获得样品，轻轻将其放置在一张A4 PVC装订封面的并观察肌肉纤维的方向。 注:在这里，我们用从第一背最长肌多丽丝的横截面，以猪最后的腰椎。试样是约12厘米长，宽8厘米和5厘米高。 </li><li>用手术刀，通过试样我做两个平行切口n中的肌肉纤维的方向，在长度约3cm和0.6厘米开。修剪阴刻肌成约0.6厘米宽×0.6厘米高×1.5厘米长的矩形。 注意:测量所述肌肉纤维的截面积的可靠性主要取决于切开肌肉的纤维取向。 </li><li>使用10厘米镊子轻轻把样品在一张塑料薄膜，与肌肉平行切开的纵向轴线向膜（ 图2A）的长边。 注:该塑料薄膜具有两个功能:保持功能，有助于固定肌肉纤维的取向以及防止样品中的裂纹，由于快速冷冻粘合功能。 </li><li>使用镊子，将肌肉组织成标记的低温小瓶的下部中间，就在入口孔之间，然后紧紧盖住小瓶（ 图2B）。 </li></ol> 3.冷冻和储存肌肉样品小号<ol><li>使用25厘米镊子，迅速浸没在液氮中整个深冷小瓶在预冷却的冷却器泡沫塑料，等待直至液氮不沸腾（约10-20或多个）。 注:当液氮沸腾的冷冻管，将浮动，那么仔细沉浸在沸腾的液氮瓶10-20秒。 </li><li>转移肌肉样品至液氮储存罐或用于长期存储一个-80℃冷冻机中。 </li></ol> 4.滑动制备<ol><li>预冷低温恒温器至-20℃和-22℃之间。 </li><li>取下并丢弃旧的切片刀，向下擦拭刀架和防卷板在低温恒温器，安装在低温恒温器一个新的切片刀，而切削厚度设置为8微米。 </li><li>从液氮贮罐的深冷小瓶转移肌肉样品或-80℃冰箱到低温恒温器，在液氮或干冰上运送它。 </LI&gt; <li>等待30分钟的样品与低温恒温器的温度达到平衡。 注意:可能触摸试样的任何设备必须预冷却，因为高温可能会导致冰晶体在试样的形成。 </li><li>安装水溶性二醇和树脂（OCT）的最佳切割温度下的制剂中的试样保持器的样品。切8微米的部分。 注意:垂直调整的切割角与肌肉纤维的取向，这是因为CSAF是肌肉纤维的横截面面积。 </li><li>安装部分向室温的MicroSlide的中心。立即将滑入在-80℃冷冻机的滑动框。不要让幻灯片在室温下干燥。 </li></ol>

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没有利益冲突，财务或其他方面，是作者声明。

在这里，我们描述了冷冻和储存肌肉组织进行肌肉功能的组织评估一个新的，多孔的冷冻管。在这个协议的临界修改的步骤是，在多孔冷冻小瓶的样品直接浸渍在液氮中。据我们所知，这是获取现有的冷冻方法中肌肉冷冻切片（见代表性的结果）优异的冷冻样品的最简单和最快的方式。 面对肌肉的研究人员面临的技术挑战是，冰晶最有可能使用的冷冻变硬的肌肉组织进行切?...

骨骼肌是从视营养和处理点产肉动物的最有价值的组分。在肉制品行业中，有两个特别重要的方面:肌肉生长的效率和所产生的肉的质量。由于肌肉的主要成分，肌肉纤维是直接关系到生长性能和动物1鲜肉的质量。例如，纤维的总数目（TNF）和纤维（CSAF）的截面积大多确定肌肉质量和肉品质;同时，肌纤维类型（FTC）强烈影响鲜肉的质量2。因此，肌纤维特征在动物操纵是增加核心的盈利能力和农场1的竞争力的一个非常有效的方法。 迄今为止，一些内在因素和外在因素已被确定操纵肌纤维characterist集成电路1。这种操纵可以通过动物的特定基因，的针对性地选择如在牛3 筒箭毒碱基因，绵羊4 美臀基因和RYR1和IGF2基因猪5来实现。此外，饮食控制和特定的激素治疗起到肌纤维特性6重要的作用。因此，结合遗传和营养因素的做法也许能提高瘦肉量和肉质。然而，在肌纤维的研究在肉类行业受到限制，因为肌纤维结构的阐明仍然是一个挑战。 肌纤维属性是使用组织化学方法，如肌球蛋白三磷酸腺苷酶（ATP酶）测定法鉴定。此方法依赖于酶位于的薄（6-8微米）冷冻切片的事实肌纤维可以用某些产品进行化学反应。然而，肌肉中的水含量是在猪，兔，小鼠，和人大于75％，而不管位置（ 即，背，腹，或后肢）7。在肌肉这种高水分含量导致通常遇到的问题-冷冻切片的制备过程中，如先前所描述8,9 -冷冻伪影。在大多数情况下，这几乎是不可能适当地冻结在屠宰场生产线的肌肉组织，根据我们的经验。 这里介绍的协议描述在我们的实验室用于冻结肌肉组织中高通量地冷冻切片一个简单而有效的方法。这种方法的亮点是被设计用于在液氮中快速冷冻的肌肉组织新冷冻小瓶。当前工作流可以同时促进组织冷冻和处理优异的肌肉冷冻切片，用清晰可见细胞质隔室和肌纤维的紧密并置到周围的组织。此外，该协议可以被应用到各种各样的用于组织分析选项，因为液氮不与组织混合。

<table><tbody><tr><td>Cryostat Microtome</td><td>&amp;nbsp;Leica</td><td>Leica CM1950</td><td></td></tr><tr><td>Digital Microscope&amp;nbsp;</td><td>Nikon</td><td>Nikon DS-U3</td><td></td></tr><tr><td>&amp;nbsp;Cryogenic Vial&amp;nbsp;&amp;nbsp; Plastic film</td><td></td><td></td><td>Designed by ourself</td></tr><tr><td>Liquid Nitrogen</td><td></td><td></td><td>Commomly-used</td></tr><tr><td>Scalpel</td><td></td><td></td><td>Commomly-used</td></tr><tr><td>10 cm forceps</td><td></td><td></td><td>Commomly-used</td></tr><tr><td>25 cm tweezer</td><td></td><td></td><td>Commomly-used</td></tr><tr><td>Safety glass</td><td></td><td></td><td>Commomly-used</td></tr><tr><td>Freezer gloves</td><td></td><td></td><td>Commomly-used</td></tr></tbody></table>

a multi-hole cryovial eliminates freezing artifacts when muscle tissues are directly immersed in liquid nitrogen

研究骨骼肌生理面临适当地处理标本清晰可见细胞质车厢，以获得部分技术挑战。另一个障碍是肌纤维周围组织的紧密并置。因为组织固定，石蜡包埋的过程导致肌纤维的收缩，凝固硬化是肌肉组织用于切片的最佳手段。然而，一个经常遇到的问题，冰晶的形成，因为肌肉中的水含量高的冰冻切片的制备过程中发生。这里介绍的协议首先描述了一种通过在液氮中浸渍它们适当冷冻肌肉组织的简单且有效的方法。与单独使用液氮的问题是，它会导致氮气屏障形成的组织，其充当绝缘体和抑制的组织的冷却旁边。为了避免这种"蒸汽膜"的效果，一个NE瓦特冷冻管被设计为增加周围组织表面的液体流的速度。这是通过在小瓶中的壁中的总共14个流入孔冲孔来实现。根据气泡动力学，在较小的气泡和机会较少液体流动的结果更高的速率形成气体屏障。当液氮流入通过入口孔冷冻管，围绕组织的流速足够快，以消除气体阻隔。相比于使用预先冷却的异戊烷中冷冻肌肉组织的方法，该协议是简单和更有效的，并且可以被用于在通量方式冻结肌肉。此外，这种方法最适用于那些没有获得异戊烷，这是在室温下极易燃的机构。

的冷冻管插图和普通实验室设备的冷冻切片的制备过程中冷冻肌肉示于图1。的冷冻小瓶在一个模具厂由聚丙烯制成。每个小瓶中总共具有14个流入孔:一种是在盖;另一个是在底部;和其余12形成四个平行线，每个具有在90℃到彼此的四个孔。这些入口孔可以液氮的流速加快组织旁边避免"蒸汽膜"时效果液氮接触组织。因此，很少有冰晶形成冷冻样本英寸重要的是?...

Watch this Scientific Journal Video about A Multi-hole Cryovial Eliminates Freezing Artifacts when Muscle Tissues are Directly Immersed in Liquid Nitrogen at JoVE.com

A Multi-hole Cryovial Eliminates Freezing Artifacts when Muscle Tissues are Directly Immersed in Liquid Nitrogen

这个协议描述的过程通过直接让他们与液氮冷冻的肌肉组织。该协议还突出一个新的离心管，可避免氮气的"毯效应"，当液氮接触样本的组织表面上。

的多孔冷冻管省去冻结工件时肌肉组织在液氮中直接浸入

Studies on skeletal muscle physiology face the technical challenge of appropriately processing the specimens to obtain sections with clearly visible ...

a-multi-hole-cryovial-eliminates-freezing-artifacts-when-muscle

Universidad de Cartagena UDEC

Research

JoVE Journal

Biology

11.2K 次观看.  Jiangxi Agricultural University. 这个协议描述的过程通过直接让他们与液氮冷冻的肌肉组织。该协议还突出一个新的离心管，可避免氮气的"毯效应"，当液氮接触样本的组织表面上。 

视频: A Multi-hole Cryovial Eliminates Freezing Artifacts when Muscle Tissues are Directly Immersed in Liquid Nitrogen

Manual Blot-and-Plunge Freezing of Biological Specimens for Single-Particle Cryogenic Electron Microscopy

Imaging biological specimens with electrons for high-resolution structure determination by single-particle cryogenic electron microscopy (cryoEM) requires a thin layer of vitreous ice containing the biomolecules of interest. Despite numerous technological advances in recent years that have propelled single-particle cryoEM to the forefront of structural biology, the methods by which specimens are vitrified for high-resolution imaging often remain the rate-limiting step. Although numerous recent efforts have provided means to overcome hurdles frequently encountered during specimen vitrification, including the development of novel sample supports and innovative vitrification instrumentation, the traditional manually operated plunger remains a staple in the cryoEM community due to the low cost to purchase and ease of operation. Here, we provide detailed methods for using a standard, guillotine-style manually operated blot-and-plunge device for the vitrification of biological specimens for high-resolution imaging by single-particle cryoEM. Additionally, commonly encountered issues and troubleshooting recommendations for when a standard preparation fails to yield a suitable specimen are also described.

This manuscript outlines the blot-and-plunge method to manually freeze biological specimens for single-particle cryogenic electron microscopy.

用于单颗粒低温电子显微镜的生物标本的手动印迹和切入式冷冻

Imaging biological specimens with electrons for high-resolution structure determination by single-particle cryogenic electron microscopy (cryoEM) requires ...

科研

生物化学

Electron Cryotomography of Bacterial Cells

While much is already known about the basic metabolism of bacterial cells, many fundamental questions are still surprisingly unanswered, including for instance how they generate and maintain specific cell shapes, establish polarity, segregate their genomes, and divide. In order to understand these phenomena, imaging technologies are needed that bridge the resolution gap between fluorescence light microscopy and higher-resolution methods such as X-ray crystallography and NMR spectroscopy.
Electron cryotomography (ECT) is an emerging technology that does just this, allowing the ultrastructure of cells to be visualized in a near-native state, in three dimensions (3D), with "macromolecular" resolution (~4nm).1, 2 In ECT, cells are imaged in a vitreous, "frozen-hydrated" state in a cryo transmission electron microscope (cryoTEM) at low temperature (&lt; -180&deg;C). For slender cells (up to ~500 nm in thickness3), intact cells are plunge-frozen within media across EM grids in cryogens such as ethane or ethane/propane mixtures. Thicker cells and biofilms can also be imaged in a vitreous state by first "high-pressure freezing" and then, "cryo-sectioning" them. A series of two-dimensional projection images are then collected through the sample as it is incrementally tilted along one or two axes. A three-dimensional reconstruction, or "tomogram" can then be calculated from the images. While ECT requires expensive instrumentation, in recent years, it has been used in a few labs to reveal the structures of various external appendages, the structures of different cell envelopes, the positions and structures of cytoskeletal filaments, and the locations and architectures of large macromolecular assemblies such as flagellar motors, internal compartments and chemoreceptor arrays.1, 2
In this video article we illustrate how to image cells with ECT, including the processes of sample preparation, data collection, tomogram reconstruction, and interpretation of the results through segmentation and in some cases correlation with light microscopy.

We illustrate here how to use electron cryotomography (ECT) to study the ultrastructure of bacterial cells in near-native states, to "macromolecular" (~4 nm) resolution.

细菌细胞的电子Cryotomography

While much is already known about the basic metabolism of bacterial cells, many fundamental questions are still surprisingly unanswered, including for ...

生物学

Tissue Triage and Freezing for Models of Skeletal Muscle Disease

Skeletal muscle is a unique tissue because of its structure and function, which requires specific protocols for tissue collection to obtain optimal results from functional, cellular, molecular, and pathological evaluations. Due to the subtlety of some pathological abnormalities seen in congenital muscle disorders and the potential for fixation to interfere with the recognition of these features, pathological evaluation of frozen muscle is preferable to fixed muscle when evaluating skeletal muscle for congenital muscle disease. Additionally, the potential to produce severe freezing artifacts in muscle requires specific precautions when freezing skeletal muscle for histological examination that are not commonly used when freezing other tissues. This manuscript describes a protocol for rapid freezing of skeletal muscle using isopentane (2-methylbutane) cooled with liquid nitrogen to preserve optimal skeletal muscle morphology. This procedure is also effective for freezing tissue intended for genetic or protein expression studies. Furthermore, we have integrated our freezing protocol into a broader procedure that also describes preferred methods for the short term triage of tissue for (1) single fiber functional studies and (2) myoblast cell culture, with a focus on the minimum effort necessary to collect tissue and transport it to specialized research or reference labs to complete these studies. Overall, this manuscript provides an outline of how fresh tissue can be effectively distributed for a variety of phenotypic studies and thereby provides standard operating procedures (SOPs) for pathological studies related to congenital muscle disease.

The analysis of skeletal muscle tissues to determine structural, functional, and biochemical properties is greatly facilitated by appropriate preparation. This protocol describes appropriate methods to prepare skeletal muscle tissue for a broad range of phenotyping studies.

组织分流和冻结的骨骼肌疾病模型

Skeletal muscle is a unique tissue because of its structure and function, which requires specific protocols for tissue collection to obtain optimal ...

Tandem High-pressure Freezing and Quick Freeze Substitution of Plant Tissues for Transmission Electron Microscopy

Since the 1940s transmission electron microscopy (TEM) has been providing biologists with ultra-high resolution images of biological materials. Yet, because of laborious and time-consuming protocols that also demand experience in preparation of artifact-free samples, TEM is not considered a user-friendly technique. Traditional sample preparation for TEM used chemical fixatives to preserve cellular structures. High-pressure freezing is the cryofixation of biological samples under high pressures to produce very fast cooling rates, thereby restricting ice formation, which is detrimental to the integrity of cellular ultrastructure. High-pressure freezing and freeze substitution are currently the methods of choice for producing the highest quality morphology in resin sections for TEM. These methods minimize the artifacts normally associated with conventional processing for TEM of thin sections. After cryofixation the frozen water in the sample is replaced with liquid organic solvent at low temperatures, a process called freeze substitution. Freeze substitution is typically carried out over several days in dedicated, costly equipment. A recent innovation allows the process to be completed in three hours, instead of the usual two days. This is typically followed by several more days of sample preparation that includes infiltration and embedding in epoxy resins before sectioning. Here we present a protocol combining high-pressure freezing and quick freeze substitution that enables plant sample fixation to be accomplished within hours. The protocol can readily be adapted for working with other tissues or organisms. Plant tissues are of special concern because of the presence of aerated spaces and water-filled vacuoles that impede ice-free freezing of water. In addition, the process of chemical fixation is especially long in plants due to cell walls impeding the penetration of the chemicals to deep within the tissues. Plant tissues are therefore particularly challenging, but this protocol is reliable and produces samples of the highest quality.

Obtaining high-quality transmission electron microscopy images is challenging, especially in the case of plant cells, which have abundant large water-filled vacuoles and aerated spaces. Tandem high-pressure freezing and quick freeze substitution greatly reduce preparation time of plant samples for TEM while producing samples with excellent ultrastructural preservation.

串联高压冷冻和植物组织中快速冷冻替代透射电子显微镜

Since the 1940s transmission electron microscopy (TEM) has been providing biologists with ultra-high resolution images of biological materials. Yet, ...

Fiber Type and Subcellular-Specific Analysis of Lipid Droplet Content in Skeletal Muscle

Skeletal muscle lipid infiltration, known as myosteatosis, increases with obesity and ageing. Myosteatosis has also recently been discovered as a negative prognostic factor for several other disorders such as cardiovascular disease and cancer. Excessive lipid infiltration decreases muscle mass and strength. It also results in lipotoxicity and insulin resistance depending on total intramyocellular lipid content, lipid droplet (LD) morphology, and subcellular distribution. Fiber type (oxidative vs glycolytic) is also important, since oxidative fibers have a greater capacity to utilize lipids. Because of their crucial implications in pathophysiology, in-depth studies on LD dynamics and function in a fiber type-specific manner are warranted.
Herein, a complete protocol is presented for the quantification of intramyocellular lipid content and analysis of LD morphology and subcellular distribution in a fiber type-specific manner. To this end, serial muscle cryosections were stained with the fluorescent dye Bodipy and antibodies against myosin heavy chain isoforms. This protocol enables the simultaneous processing of different muscles, saving time and avoiding possible artifacts and, thanks to a personalized macro created in Fiji, the automatization of LD analysis is also possible.

Increasing evidence indicates that excessive infiltration of lipids inside skeletal muscle results in lipotoxicity and diabetes. Here, we present a complete protocol, including tissue processing, staining with Bodipy, image acquisition, and analysis, to quantify the size, density, and subcellular distribution of lipid droplets in a fiber-type specific manner.

骨骼肌中脂质液滴含量的纤维类型和亚细胞特异性分析

Skeletal muscle lipid infiltration, known as myosteatosis, increases with obesity and ageing. Myosteatosis has also recently been discovered as a negative ...

医学

Plunge Freezing: A Tool for the Ultrastructural and Immunolocalization Studies of Suspension Cells in Transmission Electron Microscopy

Transmission Electron Microscopy (TEM) is an extraordinary tool for studying cell ultrastructure, in order to localize proteins and visualize macromolecular complexes at very high resolution. However, to get as close as possible to the native state, perfect sample preservation is required. Conventional electron microscopy (EM) fixation with aldehydes, for instance, does not provide good ultrastructural preservation. The slow penetration of fixatives induces cell reorganization and loss of various cell components. Therefore, conventional EM fixation does not allow for an instantaneous stabilization and preservation of structures and antigenicity. The best choice for examining intracellular events is to use cryofixation followed by the freeze-substitution fixation method that keeps cells in their native state. High-pressure freezing/freeze-substitution, which preserves the integrity of cellular ultrastructure, is the most commonly used method, but requires expensive equipment. Here, an easy-to-use and low-cost freeze fixation method followed by freeze-substitution for suspension cell cultures is presented.

This manuscript describes an easy-to-use and low-cost cryofixation method for visualizing suspension cells by transmission electron microscopy.

暴跌冻结:在透射电子显微镜的超微结构和免疫组化研究工具悬架细胞

Transmission Electron Microscopy (TEM) is an extraordinary tool for studying cell ultrastructure, in order to localize proteins and visualize ...

Cryosectioning of Contiguous Regions of a Single Mouse Skeletal Muscle for Gene Expression and Histological Analyses

With this method, consecutive cryosections are collected to enable both microscopy applications for tissue histology and enrichment of RNA for gene expression using adjacent regions from a single mouse skeletal muscle. Typically, it is challenging to achieve adequate homogenization of small skeletal muscle samples because buffer volumes may be too low for efficient grinding applications, yet without sufficient mechanical disruption, the dense tissue architecture of muscle limits penetration of buffer reagents, ultimately causing low RNA yield. By following the protocol reported here, 30 &#956;m sections are collected and pooled allowing cryosectioning and subsequent needle homogenization to mechanically disrupt the muscle, increasing the surface area exposed for buffer penetration. The primary limitations of the technique are that it requires a cryostat, and it is relatively low throughput. However, high-quality RNA can be obtained from small samples of pooled muscle cryosections, making this method accessible for many different skeletal muscles and other tissues. Furthermore, this technique enables matched analyses (e.g., tissue histopathology and gene expression) from adjacent regions of a single skeletal muscle so that measurements can be directly compared across applications to reduce experimental uncertainty and to reduce replicative animal experiments necessary to source a small tissue for multiple applications.

Consecutive cryo-sections are collected to enable histological applications and enrichment of RNA for gene expression measurements using adjacent regions from a single mouse skeletal muscle. High-quality RNA is obtained from 20 - 30 mg of pooled cryosections and measurements are directly compared across applications.

一个单一的鼠标骨骼肌的相邻区Cryosectioning的基因表达和组织学分析

With this method, consecutive cryosections are collected to enable both microscopy applications for tissue histology and enrichment of RNA for gene ...

Cryogenic Sample Loading into a Magic Angle Spinning Nuclear Magnetic Resonance Spectrometer that Preserves Cellular Viability

Dynamic nuclear polarization (DNP) can dramatically increase the sensitivity of magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy. These sensitivity gains increase as temperatures decrease and are large enough to enable the study of molecules at very low concentrations at the operating temperatures (~100 K) of most commercial DNP-equipped NMR spectrometers. This leads to the possibility of in-cell structural biology on cryopreserved cells for macromolecules at their endogenous levels in their native environments. However, the freezing rates required for cellular cryopreservation are exceeded during typical sample handling for DNP MAS NMR and this results in loss of cellular integrity and viability. This article describes a detailed protocol for the preparation and cryogenic transfer of a frozen sample of mammalian cells into a MAS NMR spectrometer.

Presented here is a protocol for cryogenic transfer of frozen samples into the dynamic nuclear polarization (DNP) magic angle spinning (MAS) nuclear magnetic resonance (NMR) probe. The protocol includes directions for rotor storage prior to the experiment and directions for viability measurements before and after the experiment.

低温样品加载到魔法角度旋转核磁共振光谱仪中，可保持细胞生存能力

Dynamic nuclear polarization (DNP) can dramatically increase the sensitivity of magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy. ...

Regulating Temperature in the Lab: Preserving Samples Using Cold

Preservation of laboratory samples, specimens, and reagents using extreme cold is routinely performed in biomedical research labs. This video will discuss some of the methods for keeping laboratory samples cold and will explain the correct cooling method to use for each experimental requirement.
For example, cooling agents, such as ice and dry ice, are typically used when keeping samples cold during experiments. This video discusses the physical properties of the most commonly used cooling agents, as well as safety precautions for working with them.
When it comes to keeping samples cold in between experiments, cooling equipment, including laboratory grade refrigerators and freezers can be used to preserve samples for extended period of time. Also discussed in this video are types of samples and reagents that can be stored in the commonly-available laboratory cooling equipment.
Finally, the concept of cryopreservation is introduced as a process through which tissues, cells, and biomolecules are cooled to sub-zero temperatures, thereby effectively stopping all sample-degrading biological activity. Several methods of cryopreservation are discussed that minimize or eliminate the formation of damaging ice crystals.

Preserving Samples Using Cold: Cooling Agents and Instruments, and Cryopreservation

实验室中的温度控制:冷却保存样品

Preservation of laboratory samples, specimens, and reagents using extreme cold is routinely performed in biomedical research labs.  This video will ...

教育

JoVE Science Education

基础生物学

常用的实验室技术

Snap Freezing of Muscle Tissue for Sectioning: A Protocol to Obtain Ultrathin Sections of Rapidly Frozen Murine Muscle Tissue

Source: Bonetto, A. et al. <a href="https://jove.unicartagenaproxy.elogim.com/video/54893" target="_blank">The Colon-26 Carcinoma Tumor-bearing Mouse as a Model for the Study of Cancer Cachexia.</a> J. Vis. Exp. (2016)
This video describes the procedure for snap freezing muscle tissue and obtaining its thin sections. The technique can help study cancer-related cachexia in colon cancer mouse models.