High-Throughput Contractility Assay for Human Stem Cell-Derived Cardiomyocytes.
High-Throughput Contractility Assay for Human Stem Cell-Derived Cardiomyocytes.
复制标题
人类干细胞来源的心肌细胞的高通量收缩性测定。
DOI：
10.1161/circresaha.119.314844
复制
发表时间：
2019
影响因子：
20.1
通讯作者：
Kim,Deok-Ho
中科院分区：
文献类型：
--
作者：
Miklas,JasonW;Salick,MaxR;Kim,Deok-Ho
与快速傅立叶变换一样，小波变换通常用于图像处理中的去噪、压缩和目标检测。这些变换的相似之处在于它们都将信号或图像转换为频域，允许研究人员快速量化信号中存在的任何重复模式（例如特定的音频音高）或图像中存在的重复模式（例如横纹肌原纤维）。小波的优点是它们提供了图像内重复图案的频率沿着重复结构的位置。相比之下，快速傅立叶变换仅包含频率信息，因此如果整个分析区域包含均匀的单向重复结构，则更有效。为了使用SarcTrack，用户提供一组离散的距离和角度，可以定义任何2个相邻Z盘/M带的相对距离。然后，该算法生成对标准Mortlet母小波和变换这些对的基础上提供的距离和角度的可能列表。这将创建一组小图像，这些图像在各种距离和旋转下类似于理想的肌节。然后，该算法在收缩细胞的视频上逐帧卷积这些小波对。卷积算法在图像中找到与任何定义的小波对非常相似的区域，将该区域标记为已知旋转和距离的肌节。这些小波对允许在单个肌节尺度上量化Z线和M线之间的距离和角度，而不要求肌原纤维是单向的并且具有均匀的肌节长度。这种分析技术的一个有趣的特征是跟踪hPSC-CM中肌节的各种比对的能力。由于可以对细胞中的各种肌节进行全局跟踪，因此导致肌节畸形/解体的病变细胞或药物将在分析值中表现为大的分布。不成熟的hPSC-CM具有较差的肌原纤维排列。尽管hPSC-CM中的许多优势肌原纤维可能平行于心肌细胞的长轴，但将存在随机分布的许多其他肌原纤维。因此，与细胞中的主要肌原纤维相比，这些其他肌原纤维与长轴或收缩轴具有随机取向，将最有可能具有不同的收缩特性。因此，在评估的肌节分析中会发现大量的变异。令人印象深刻的是，我们现在有了能够测量细胞中如此多肌原纤维的分辨率的工具。将联合收割机这种成像技术与当前的细胞图案化策略相结合以产生良好排列的心肌细胞或其他成熟技术以获得成熟和排列的肌节用于分析将是令人兴奋的。这将有助于减少数据中产生的噪音量，非常适合疾病建模和药物发现研究。目前的软件工具仅限于收缩测量。然而，这种成像方式可以与表达钙或电压敏感荧光团的其他工程细胞系结合。这种多路复用特征将拓宽进行筛选潜力的视野，因为可以同时评估收缩和电生理特性。用户定义的小波核跨越离散的距离和角度的集合的要求允许错位肌节检测，然而，在计算能力的显着成本。此外，这迫使分析人员在检测分辨率和分析速度之间进行平衡。第一次...
Like Fast Fourier Transforms, wavelet transforms are often used in image processing for denoising, compression, and object detection. These transforms are similar in that they both convert a signal or image into the frequency domain, allowing a researcher to quickly quantify any repeating pattern that is present in a signal (such as a specific audio pitch) or a repeating pattern that is present in an image (such as a striated myofibril). The advantage of wavelets is that they provide both the frequency of a repeating pattern within an image, along with the location of that repeating structure. In contrast, Fast Fourier Transform only contains frequency information and thus is more effective if the entire analyzed region contains a uniform, unidirectional repeating structure. To use SarcTrack, a user provides a discrete set of distances and angles that could define the relative distances of any 2 neighboring Z-disks/M-bands. The algorithm then generates pairs of standard Mortlet mother wavelets and transforms these pairs based on the possible list of distances and angles provided. This creates a bank of small images that resemble ideal sarcomeres under a variety of distances and rotations. The algorithm then convolutes these wavelet pairs frame-by-frame over a video of contracting cells. The convolution algorithm finds regions within the image that closely resemble any of the defined wavelet pairs, labeling that region as a sarcomere of known rotation and distance. These wavelet pairs allow quantification of distances and angles between Z-lines and M-lines at the single sarcomere scale, with no requirement that myofibrils be unidirectional and have uniform sarcomere lengths. One of the interesting features of this analysis technique is the ability to track various alignments of sarcomeres in hPSC-CMs. Because global tracking of various sarcomeres in a cell can be performed, a diseased cell or a drug that results in malformation/disassembly of sarcomeres will manifest as a large distribution in analyzed values. Immature hPSC-CMs have poor arrangement of myofibrils. Whereas many of the dominant myofibrils in an hPSC-CM will probably be parallel to the long axis of the cardiomyocyte, there will be many other myofibrils randomly distributed. Consequently, these other myofibrils with random orientations to the long axis or the axis of contraction will most likely have different contractile properties compared with the main myofibrils in the cell. As a result, there will be a great deal of variation found within the assessed sarcomere analysis. It is impressive that we now have tools that have the resolution to measure so many myofibrils in the cell. It would be exciting to combine this imaging technology with current cell patterning strategies to generate well-aligned cardiomyocytes or other maturation techniques to obtain mature and aligned sarcomeres for analysis. 7 This will help to reduce the amount of noise generated in the data and be well suited to disease modeling and drug discovery studies. The current software tool is restricted to contractile measurements. However, this imaging modality could be coupled with other engineered cell lines that express calcium or voltage sensitive fluorophores. This multiplexing feature would broaden the field of view for the screening potential performed as both contractile and electrophysiological properties could be assessed at once. The requirement of user-defined wavelet kernels spanning a discrete set of distances and angles does allow for misaligned sarcomere detection, however, at a significant cost of computational power. Additionally, this forces the analyst to balance between detection resolution and speed of analysis. A first …
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影响因子：
23.9
作者：
Burridge, Paul W.;Keller, Gordon;Gold, Joseph D.;Wu, Joseph C.
通讯作者：
Wu, Joseph C.
影响因子：
4.1
作者：
Boudou, Thomas;Legant, Wesley R.;Chen, Christopher S.
通讯作者：
Chen, Christopher S.
DOI：
10.1016/j.ymeth.2015.09.005
发表时间：
2016-02-01
期刊：
Methods (San Diego, Calif.)
影响因子：
--
作者：
Beussman KM;Rodriguez ML;Leonard A;Taparia N;Thompson CR;Sniadecki NJ
通讯作者：
Sniadecki NJ
影响因子：
5.5
作者：
Pasqualin, Come;Gannier, Francois;Maupoil, Veronique
通讯作者：
Maupoil, Veronique
DOI：
10.1007/978-1-4939-8597-5_7
发表时间：
2018-01-01
期刊：
EXPERIMENTAL MODELS OF CARDIOVASCULAR DISEASES: METHODS AND PROTOCOLS
影响因子：
--
作者：
Gorski, Przemek A.;Kho, Changwon;Oh, Jae Gyun
通讯作者：
Oh, Jae Gyun