Any biological material contains dissolved gases that affect physical and biological processes associated with cooling and freezing. However, in the cryobiology literature, little attention has been paid to the effect of gasses on cryopreservation. We studied the influence of helium, neon, krypton, xenon, argon, nitrogen, and sulfur hexafluoride on the survivability of HeLa and L929 cell lines during cryopreservation. Saturation of a cell suspension with helium, neon, and sulfur hexafluoride enhanced survival of HeLa and L929 cells after cryopreservation. Helium exerted the most significant effect. For a range of noble gases, the efficiency of the positive effect decreased as the molecular mass of the gas increased. This paper discusses possible mechanisms for the influence of gases on the cryopreservation of biological material. The most probable mechanism is the disruption of the frozen solution structure with gas-filled microbubbles produced during water crystallization. Ultimately, it was concluded that helium and neon can be used to improve methods for cryopreservation of cell suspensions with a low concentration of conventional penetrating cryoprotectants or even without them.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.cryobiol.2021.07.004 | DOI Listing |
J Chem Phys
January 2025
Institute of Thermodynamics and Thermal Process Engineering, University of Stuttgart, Pfaffenwaldring 9, D-70569 Stuttgart, Germany.
Effective potential methods, obtained by applying a quantum correction to a classical pair potential, are widely used for describing the thermophysical properties of fluids with mild nuclear quantum effects. In case of strong nuclear quantum effects, such as for liquid hydrogen and helium, the accuracy of these quantum corrections deteriorates significantly, but at present no simple alternatives are available. In this work, we solve this issue by developing a new, three-parameter corresponding-states principle that remains applicable in the regions of the phase diagram where quantum effects become significant.
View Article and Find Full Text PDFPhys Med Biol
January 2025
Department of Accelerator and Medical Physics, National Institutes for Quantum Science and Technology, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, JAPAN.
The tumor microenvironment characterized by heterogeneously organized vasculatures causes intra-tumoral heterogeneity of oxygen partial pressure at the cellular level, which cannot be measured by current imaging techniques. The intra-tumoral cellular heterogeneity may lead to a reduction of therapeutic effects of radiation. The purpose of this study was to investigate the effects of the heterogeneity on biological effectiveness of H-, He-, C-, O-, and Ne-ion beams for different oxygenation levels, prescribed dose levels, and cell types.
View Article and Find Full Text PDFNanoscale
November 2024
Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC-Universidad de Zaragoza, 50018 Zaragoza, Spain.
A direct nanowriting procedure using helium- and neon-focused ion beams and spin-coated organometallic thin films is introduced and applied to the fabrication of Pd-enriched metallic structures in a single lithography step. This process presents significant advantages over multi-step resist-based lithography and focused beam-induced deposition using gaseous precursors, such as its simplicity and speed, respectively. The optimized process leads to Pd-rich structures with low electrical resistivity values of 141 and 152 μΩ cm under Ne or He fluences of 1000 and 5000 μC cm, respectively.
View Article and Find Full Text PDFSensors (Basel)
September 2024
V.I. Il'ichev Pacific Oceanological Institute FEB RAS, 690041 Vladivostok, Russia.
This paper describes the design and principle of operation of a 20 m laser strainmeter of unequal-arm type created on the basis of a Michelson interferometer and frequency-stabilized helium-neon laser. The interferometry methods used allow the measurement of the displacement of an Earth's crust section on the base of the laser strainmeter with an accuracy of 30 pm in the frequency range from 0 (conventionally) to 1000 Hz. This laser strainmeter, when connected to an accurate time system providing an accuracy of 1 μs, should structurally become a part of the laser interferometric seismoacoustic observatory, consisting of spatially separated laser strainmeters installed in various regions of Russia.
View Article and Find Full Text PDFBMC Plant Biol
August 2024
Pharmacognosy Department, Isfahan Pharmaceutical Sciences Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
Background: In the past two decades, the impacts of Helium-Neon (He-Ne) laser on stress resistance and secondary metabolism in plants have been studied, but the signaling pathway which by laser regulates this process remains unclear. Therefore, the current study sought to explore the role of RBOH-dependent signaling in He-Ne laser-induced salt tolerance and elicitation of secondary metabolism in Salvia officinalis. Seeds were primed with He-Ne laser (6 J cm) and peroxide hydrogen (HO, 5 mM) and 15-old-day plants were exposed to two salinity levels (0, 75 mM NaCl).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!