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Applications of Antiviral Nanoparticles in Cancer Therapy
Published in Devarajan Thangadurai, Saher Islam, Charles Oluwaseun Adetunji, Viral and Antiviral Nanomaterials, 2022
Anusha Konatala, Sai Brahma Penugonda, Fain Parackel, Sudhakar Pola
The antiviral activity of nanoparticles can be measured through different assays. To name a few, techniques like flow cytometry, western blot assay, and real-time PCR are frequently used. Among the imaging techniques applicable, transmission electron microscopy gives clear images of nanoparticles and their binding sites. Some of them are viral quantification assays measuring the virus, while some measure cell death. The plaque assay determines the functionality of nanoparticles by calculating the plaque-forming units per milliliter (PFU value of the virus) (Rigotto et al. 2011; Chen and Liang 2020).
Methods for the Morphological Study of Tracheal and Bronchial Glands
Published in Joan Gil, Models of Lung Disease, 2020
At the electron microscopic (transmission) level, mucous cells have flat, basal nuclei and lucent granules (300-1800 nm in diameter) and the limiting membranes of many of these granules are fused in human lung. In contrast, serous cells have round, centrally located nuclei and granules (300-1000 nm in diameter) with dense contents, and the membranes of most serous cells are not fused (Meyrick and Reid, 1970) (Figure 7). Although transmission electron microscopy has been used for ultrastructural examination of secretory granules by almost all investigators, Kawada et al. (1981) used scanning electron microscopy (SEM) to observe secretory granules in human bronchial gland using a freeze-fracture method that provides tridimensional images of secretory granules. However, the term electron microscopy used in this chapter refers to transmission electron microscopy by ultrathin sectioning except where stated otherwise.
Identifying Nanotoxicity at the Cellular Level Using Electron Microscopy
Published in Suresh C. Pillai, Yvonne Lang, Toxicity of Nanomaterials, 2019
Kerry Thompson, Alanna Stanley, Emma McDermott, Alexander Black, Peter Dockery
Conventionally it is regarded that there are two main types or modes of electron microscopy, transmission electron microscopy (TEM) and scanning electron microscopy (SEM). There have been many adaptations of these techniques, the base microscopes and their associated specimen preparations which include low temperature and cryo techniques. To ensure that the specimen is able to withstand the electron beam, various preparatory techniques (Figure 7.1) must be carried out and will be discussed in greater detail in Section 7.3. When gathering three-dimensional (3D) information about a specimen, the microscopist generally employs the SEM, where it is used to visualise the surface topography of a specimen. TEM images are generally two dimensional (2D) in nature but in recent years and with advances in technology, computational power, and software packages a series of 2D TEM images can be collected via electron tomography (ET) and reconstructed to create a 3D model of the structure of interest.
Progress in the development of stabilization strategies for nanocrystal preparations
Published in Drug Delivery, 2021
Jingru Li, Zengming Wang, Hui Zhang, Jing Gao, Aiping Zheng
The sizes and shapes of nanocrystals were analyzed via scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In SEM, image results are generated through the interaction between the electron beam and atoms at various depths in the sample. For example, by collecting secondary electrons and backscattered electrons, information about the microstructure of the material can be obtained (Figure 7). In a transmission electron microscope, an image is obtained by capturing transmitted electrons in a sample. The accelerated and clustered electron beam can be transmitted to a very thin sample, and the electrons collide with the atoms in the sample and change direction, thereby generating solid angle scattering, which can be used to observe the ultrastructures of particles, and the resolution can reach 0.1 ∼ 0.2 nm (Figure 8).
Monoclonal glomerulopathy with features of cryoglobulinemic glomerulopathy in murine multiple myeloma model
Published in Ultrastructural Pathology, 2020
Ping L. Zhang, Guillermo A. Herrera, Bei Liu
A Vk*MYC model of myeloma in transgenic mice has been previously reported.21 In the current study, the Vk*MYC transgenic mice and wild-type control littermates were bred and maintained according to the established guidelines and an approved protocol by the Medical University of South Carolina Institutional Animal Care and Use Committee. Six wild-type control littermates and 12 Vk*MYC transgenic mice with myeloma at 50–70 weeks were used for the study. Each mouse kidney was divided into two parts. One part was frozen for immunofluorescent studies. The frozen renal tissue was cut for two-step immunofluorescent stains for kappa, and lambda (1:50 dilution for primary kappa and lambda antibodies, Southern Biotechnology Associates, Birmingham, AL). Immunofluorescent staining evaluation was conducted by two of the authors working independently (PLZ, BL). The other part of each kidney was fixed in 3% of glutaraldehyde, and underwent routine processing for electron microscopy. The tissue for electron microscopy was post-fixed in osmium tetroxide, embedded in resin, sectioned, and stained with Methylene Blue-Azure II for light microscopic survey. Tissue was further thin sectioned and stained with uranyl acetate and lead citrate. The grids for electron microscopy were examined using a transmission electron microscope.
Use of electron microscopy to study platelets and thrombi
Published in Platelets, 2020
Maurizio Tomaiuolo, Rustem I. Litvinov, John W. Weisel, Timothy J. Stalker
The study of platelet biology using electron microcopy methods has a long and rich history. It was not long after the introduction of the electron microscope that the first studies of platelet ultrastructure using transmission electron microscopy were published [1]. Conventional electron microscopy is divided into transmission electron microscopy (TEM) and scanning electron microscopy (SEM). In TEM, a beam of electrons is transmitted through a thin section in order to visualize the internal structures. By contrast in SEM, a focused beam of electrons is used to scan the surface of a specimen. A considerable amount of work went into developing the protocols to fix soft tissues so that they could be imaged by electron microscopy, work strongly motivated by the need to visualize tissues and their internal structures in ways that were not possible with any other microscopy technique before. Once the proper fixation protocols had been developed, electron microscopy became instrumental to study platelets, both for basic research [2] and as a diagnostic tool [3]. Today, conventional TEM and SEM approaches remain valuable tools in platelet and thrombosis research, even as EM approaches continue to evolve and new imaging modalities are developed.