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Low Energy Particle Accelerators and Laboratories
Published in Vlado Valković, Low Energy Particle Accelerator-Based Technologies and Their Applications, 2022
The Jefferson Lab Low Energy Recirculator Facility is powered by a smaller SRF accelerator. Formerly known as the Free-Electron Laser (FEL), the facility holds power records in the production of infrared, ultraviolet and terahertz laser light. The FEL was used in a variety of scientific studies, such as developing processes for producing high-quality carbon and boron-nitride nanotubes, identifying laser light wavelengths for use in medical treatments and in micromachining studies.
Magnetic Control of Biogenic Micro-Mirror
Published in Shoogo Ueno, Bioimaging, 2020
Optical fiber-based measurement systems were used with the superconducting magnet or the electromagnet, depending on the magnetic field intensity required. In the magnetic field region were an optical quartz sample cell, mirrors (if necessary), and optical fibers from a light source and to a cooled CCD spectrophotometer. The magnetic field, incident light, and observation directions had three different modes (MODE-I, II, III) for the evaluation of light scattering anisotropies of the micro-crystals in an aqueous solution, as depicted in Figure 10.2(b). Micro-crystals of cellulose and hexagonal boron nitride (h-BN) were prepared from powder products (Ceolus, from pulp Type-Iβ cellulose, Asahi Kasei co. Ltd., Japan, and boron nitride powder GP, DENKA co Ltd., Japan).
Effects of boron-containing compounds on immune responses: review and patenting trends
Published in Expert Opinion on Therapeutic Patents, 2019
Karla S. Romero-Aguilar, Ivonne M. Arciniega-Martínez, Eunice D. Farfán-García, Rafael Campos-Rodríguez, Aldo A. Reséndiz-Albor, Marvin A. Soriano-Ursúa
Boric acid is the BCC with the most reported effects on the immune response, acting as the spearhead for BCC pharmacology. However, its use is limited because other compounds, with higher potency and efficacy on the identified targets and responding to the mechanism for its action, have been identified. BCCs involved in immunomodulation are key in patenting trends and drug development. In this sense, the potential applications of nanotechnological boron-based compounds are relevant, as an example, boron-nitride nanotubes and hexagonal boron nitrides are useful as efficient nanocarriers for cancer drugs and potent agents that modulate the response to neoplastic cells [48,49,134–139]. Recently, drugs acting on the proteasome and inflammasome have been applied in medicine, with good results in cancer, infectious diseases, and other maladies. Active research in this field has allowed for the identification and development of compounds modulating innate and adaptive immunity, along with the effects formerly identified for BCCs, which include modulation of cluster differentiation and production of cytokines. In addition, BCCs exert effects on inflammation induced by infectious and noninfectious agents. The potential of several compounds for use in humans after descriptions of a safe toxicological profile, as well as their frequent use without toxicity, comparable to boron-free compounds, indicates that the pharmaceutical industry and academic research groups should expend resources for understanding the role and limitations of BCCs that act as potential drugs in pathologies associated with immune disorder.
In vivo Toxicity Assessment of Silver Nanoparticles in Homeostatic versus Regenerating Planarians
Published in Nanotoxicology, 2019
Nathalie Leynen, Frank G.A.J Van Belleghem, Annelies Wouters, Hannelore Bove, Jan-Pieter Ploem, Elsy Thijssen, Sabine A.S. Langie, Robert Carleer, Marcel Ameloot, Tom Artois, Karen Smeets
In this study, we used the freshwater planarian Schmidtea mediterranea to study underlying mechanisms of nanoparticle toxicity on stem cells, regeneration and development in vivo. Planarians have gained interest as toxicological models for compounds such as carcinogens or neurotoxicants (Inden et al. 2004; Gentile, Cebrià, and Bartscherer 2011; Hagstrom et al. 2015; Stevens et al. 2017). They were established as a model for assessing nanotoxicity in studies on boron nitride NPs (Salvetti et al. 2015) and AgNPs (Kustov et al. 2014). Because of their large pool of pluripotent stem cells, planarians can regenerate any damaged or amputated tissue, including the entire nervous system, which makes them attractive organisms for (neuro-)developmental research (Hagstrom, Cochet-Escartin, and Collins 2016). In addition, as regeneration is induced by amputation, adults can be studied in parallel with genetically identical regenerating animals. We exposed the worms to uncoated (NC-AgNPs) and PVP-coated (PVP-AgNPs) spherical AgNPs with a nominal size of 20 nm (actual primary particle size: ±35 nm) to address changes in physicochemical parameters and toxic effects related to the addition of a coating. Homeostatic animals were compared to regenerating animals in order to specifically screen for stem cell-related and developmental effects. To ensure that our results were reproducible and meaningful, an important part of this study was devoted to the determination of the particle characteristics and cellular uptake. This enabled us to link variations in physicochemical parameters during AgNP exposure with the observed effects.
Ecotoxicological assessment of commercial boron nitride nanotubes toward Xenopus laevis tadpoles and host-associated gut microbiota
Published in Nanotoxicology, 2021
Lauris Evariste, Emmanuel Flahaut, Clément Baratange, Maialen Barret, Florence Mouchet, Eric Pinelli, Anne Marie Galibert, Brigitte Soula, Laury Gauthier
Boron nitride nanotubes were obtained from BNNT LLC (USA). They correspond to the ‘BNNT P1-Beta Products’ range of materials as classified on the website of the company (http://www.bnnt.com/products). This material is described as containing hexagonal boron nitride (h-BN) and boron as well as being catalyst free (elemental B and N > 99.9%) with ca. 25% of Boron in addition to BNNT. According to the manufacturer, the specific surface area is >200 m2/g. Sample was used as-received, after simple grinding (agate mortar and pestle) in order to make it suitable for the experiments and characterization. The sample was characterized by X-ray diffraction (XRD), Brunauer-Emmet-Teller (BET), TGA, TEM, Raman and chemical elemental analysis.