The Experts below are selected from a list of 48 Experts worldwide ranked by ideXlab platform
Timothy J. Garrett - One of the best experts on this subject based on the ideXlab platform.
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Precast Gelatin-Based Molds for Tissue Embedding Compatible with Mass Spectrometry Imaging
Analytical Chemistry, 2017Co-Authors: Emily L. Gill, Vinata Vedam-mai, Richard A. Yost, Timothy J. GarrettAbstract:Preparation of Tissue for matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI) generally involves Embedding the Tissue followed by freezing and cryosectioning, usually between 5-25 μm thick, depending on the Tissue type and the analyte(s) of interest. The brain is approximately 60% fat; it therefore lacks rigidity and poses structural preservation challenges during sample preparation. Histological sample preparation procedures are generally transferable to MALDI-MSI; however, there are various limitations. Optimal cutting temperature compound (OCT) is com-monly used to embed and mount fixed Tissue onto the chuck inside the cryostat during cryosectioning. However, OCT con-tains potential interferences that are detrimental to MALDI-MSI, whilst fixation is undesirable for the analysis of some ana-lytes either due to extraction or chemical modification (i.e. polar metabolites). Therefore a method for both fixed and fresh Tissue compatible with MALDI-MSI and histology is desirable ...
Emily L. Gill - One of the best experts on this subject based on the ideXlab platform.
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Precast Gelatin-Based Molds for Tissue Embedding Compatible with Mass Spectrometry Imaging
Analytical Chemistry, 2017Co-Authors: Emily L. Gill, Vinata Vedam-mai, Richard A. Yost, Timothy J. GarrettAbstract:Preparation of Tissue for matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI) generally involves Embedding the Tissue followed by freezing and cryosectioning, usually between 5-25 μm thick, depending on the Tissue type and the analyte(s) of interest. The brain is approximately 60% fat; it therefore lacks rigidity and poses structural preservation challenges during sample preparation. Histological sample preparation procedures are generally transferable to MALDI-MSI; however, there are various limitations. Optimal cutting temperature compound (OCT) is com-monly used to embed and mount fixed Tissue onto the chuck inside the cryostat during cryosectioning. However, OCT con-tains potential interferences that are detrimental to MALDI-MSI, whilst fixation is undesirable for the analysis of some ana-lytes either due to extraction or chemical modification (i.e. polar metabolites). Therefore a method for both fixed and fresh Tissue compatible with MALDI-MSI and histology is desirable ...
Vladimir Havlicek - One of the best experts on this subject based on the ideXlab platform.
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poly n 2 hydroxypropyl methacrylamide based Tissue Embedding medium compatible with maldi mass spectrometry imaging experiments
Analytical Chemistry, 2011Co-Authors: Martin Strohalm, J Strohalm, Filip Kaftan, Lukas Krasný, Michael Volný, Petr Novak, Karel Ulbrich, Vladimir HavlicekAbstract:Traditional Tissue-sectioning techniques for histological samples utilize various Embedding media to stabilize the Tissue on a sectioning target and to provide a smooth cutting surface. Due to the ion suppression effect in MALDI ionization and number of background peaks in the low-mass region, these media are not suitable for mass spectrometry imaging (MSI) experiments. To overcome this, droplets of water are often used to mount the Tissue on a sectioning target, but the ice block formed around the Tissue does not provide a good support for sectioning of fragile samples. In this work, we propose a novel Embedding media, compatible with MALDI ionization and MSI experiments, based on poly[N-(2-hydroxypropyl)methacrylamide] (pHPMA). Using a reversible addition–fragmentation chain transfer polymerization technique, well-defined pHPMA polymer with narrow mass distribution was prepared. Benefits of the resulted pHPMA-based Embedding media were tested on different Tissue samples.
Charles E Murry - One of the best experts on this subject based on the ideXlab platform.
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An Improved Cryosection Method for Polyethylene Glycol Hydrogels Used in Tissue Engineering
Tissue Engineering Part C: Methods, 2013Co-Authors: Jia-ling Ruan, Nathaniel L. Tulloch, Veronica Muskheli, E. Erin Genova, Peter D. Mariner, Kristi S. Anseth, Charles E MurryAbstract:The high water content of hydrogels allows these materials to closely mimic the native biological extracellular conditions, but it also makes difficult the histological preparation of hydrogel-based bioengineered Tissue. Paraffin-Embedding techniques require dehydration of hydrogels, resulting in substantial collapse and deformation, whereas cryosectioning is hampered by the formation of ice crystals within the hydrogel material. Here, we sought to develop a method to obtain good-quality cryosections for the microscopic evaluation of hydrogel-based Tissue-engineered constructs, using polyethylene glycol (PEG) as a test hydrogel. Conventional sucrose solutions, which dehydrate cells while leaving extracellular water in place, produce a hydrogel block that is brittle and difficult to section. We therefore replaced sucrose with multiple protein-based and nonprotein-based solutions as cryoprotectants. Our analysis demonstrated that overnight incubation in bovine serum albumin (BSA), fetal bovine serum (FBS), polyvinyl alcohol (PVA), optimum cutting temperature (OCT(®)) compound, and Fisher HistoPrep frozen Tissue-Embedding media work well to improve the cryosectioning of hydrogels. The protein-based solutions give background staining with routine hematoxylin and eosin, but the use of nonprotein-based solutions PVA and OCT reduces this background by 50%. These methods preserve the Tissue architecture and cellular details with both in vitro PEG constructs and in constructs that have been implanted in vivo. This simple hydrogel cryosectioning technique improves the methodology for creation of good-quality histological sections from hydrogels in multiple applications.
Sameer R. Sonkusale - One of the best experts on this subject based on the ideXlab platform.
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A toolkit of thread-based microfluidics, sensors, and electronics for 3D Tissue Embedding for medical diagnostics
Microsystems & Nanoengineering, 2016Co-Authors: Pooria Mostafalu, Kyle A. Alberti, Qiaobing Xu, Mohsen Akbari, Ali Khademhosseini, Sameer R. SonkusaleAbstract:Threads, traditionally used in the apparel industry, have recently emerged as a promising material for the creation of Tissue constructs and biomedical implants for organ replacement and repair. The wicking property and flexibility of threads also make them promising candidates for the creation of three-dimensional (3D) microfluidic circuits. In this paper, we report on thread-based microfluidic networks that interface intimately with biological Tissues in three dimensions. We have also developed a suite of physical and chemical sensors integrated with microfluidic networks to monitor physiochemical Tissue properties, all made from thread, for direct integration with Tissues toward the realization of a thread-based diagnostic device (TDD) platform. The physical and chemical sensors are fabricated from nanomaterial-infused conductive threads and are connected to electronic circuitry using thread-based flexible interconnects for readout, signal conditioning, and wireless transmission. To demonstrate the suite of integrated sensors, we utilized TDD platforms to measure strain, as well as gastric and subcutaneous pH in vitro and in vivo.Biodevices: Woven and wearable three-dimensional circuitryImplantable and wearable diagnostic devices could integrate more smoothly into living Tissue through 3D thread-based platforms. Such devices will transform the diagnosis and treatment of diseases by facilitating continuous, in situ monitoring of an individual’s health. However, as well as requiring costly and highly specialized manufacturing procedures, existing substrates are limited to two dimensions, which restricts their ability to penetrate multiple layers of Tissue. In their quest for suitable alternatives, Sameer Sonkusale at Tufts University, United States, and his co-workers have developed a microfluidic platform that uses threads as substrates and functional constituents. The threads exhibit different physical, chemical and biological functions, producing a network of sensors, microfluidic channels and electronic components. The platform can measure both pH and strain in vitro and in vivo, which demonstrates its potential for implementation in clothing and implants.
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a toolkit of thread based microfluidics sensors and electronics for 3d Tissue Embedding for medical diagnostics
Microsystems & Nanoengineering, 2016Co-Authors: Pooria Mostafalu, Kyle A. Alberti, Qiaobing Xu, Mohsen Akbari, Ali Khademhosseini, Sameer R. SonkusaleAbstract:Implantable and wearable diagnostic devices could integrate more smoothly into living Tissue through 3D thread-based platforms. Such devices will transform the diagnosis and treatment of diseases by facilitating continuous, in situ monitoring of an individual’s health. However, as well as requiring costly and highly specialized manufacturing procedures, existing substrates are limited to two dimensions, which restricts their ability to penetrate multiple layers of Tissue. In their quest for suitable alternatives, Sameer Sonkusale at Tufts University, United States, and his co-workers have developed a microfluidic platform that uses threads as substrates and functional constituents. The threads exhibit different physical, chemical and biological functions, producing a network of sensors, microfluidic channels and electronic components. The platform can measure both pH and strain in vitro and in vivo, which demonstrates its potential for implementation in clothing and implants.