Artículos de revistas: "Vitrification process"

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Faltus, Milos, Alois Bilavcik, Stacy Denise Hammond Hammond, and Jiri Zamecnik. "Vitrification process control by DSC." Cryobiology 109 (December 2022): 23–24. http://dx.doi.org/10.1016/j.cryobiol.2022.11.074.

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Odagaki, Takashi, and Akira Yoshimori. "Localization transition in the vitrification process." Physica B: Condensed Matter 296, no. 1-3 (2001): 174–79. http://dx.doi.org/10.1016/s0921-4526(00)00796-1.

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Short, Rick, Nick Gribble, Edward Turner, and Andrew D. Riley. "Using the Vitrification Test Rig for Process Improvements on the Waste Vitrification Plants." Advances in Science and Technology 73 (October 2010): 176–82. http://dx.doi.org/10.4028/www.scientific.net/ast.73.176.

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The Vitrification Test Rig (VTR) is a full scale non-active waste vitrification plant (WVP), that replicates the lines used for immobilising highly active reprocessing waste at Sellafield in the UK. In the high level waste (HLW) vitrification process, liquid HLW is dried in a rotating tube furnace then mixed with an alkali borosilicate glass frit. This mixture is heated to form a homogeneous product glass that is poured, cooled and stored in steel canisters. The primary function of the VTR is to trial and develop methods to increase the efficiency of high level waste processing at the active WVP. Efficiency gains are mainly achieved by increasing the rate at which the immobilised product is created and by increasing the ratio of HLW to glass frit in the product. The VTR has also been used to investigate the chemistry of various process additions and conditions, the effects of potential fault scenarios, and the processing of dilute waste streams that will be received by WVP in the future. All of these areas have the potential to improve processing efficiency through the optimisation of process conditions and the minimisation of unplanned plant outages. This paper discusses several VTR campaigns that have led to overall improvements of WVP operation.

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Romero, M., and J. M. Rincón. "El proceso de vitrificación/cristalización controlada aplicado al reciclado de residuos industriales inorgánicos." Boletín de la Sociedad Española de Cerámica y Vidrio 39, no. 1 (2000): 155–63. http://dx.doi.org/10.3989/cyv.2000.v39.i1.884.

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Peymani, R., S. Najmabadi, H. Badrzadeh, T. M. Macaso, Z. Azadbadi, and A. Ahmady. "Comparison of two vitrification solutions on the outcome of vitrification/thaw process in a closed vitrification system, V-Kim." Fertility and Sterility 90 (September 2008): S286—S287. http://dx.doi.org/10.1016/j.fertnstert.2008.07.1105.

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F. N. C, Anyaegbunam. "Hazardous Waste Vitrification by Plasma Gasification Process." IOSR Journal of Environmental Science, Toxicology and Food Technology 8, no. 3 (2014): 15–19. http://dx.doi.org/10.9790/2402-08311519.

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Schug, Brett W., and Matthew J. Realff. "Analysis of waste vitrification product-process systems." Computers & Chemical Engineering 22, no. 6 (1998): 789–800. http://dx.doi.org/10.1016/s0098-1354(98)80002-1.

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Masrat-Un-Nisa, Asloob Ahmad Malik, Khursheed Ahmad Sofi, Arjuma Khatun, and Nahida Yousuf. "Recent Advancements in Vitrification Cryodevices for Gamete and Gonadal Tissue." Cryoletters 43, no. 3 (2022): 129–39. http://dx.doi.org/10.54680/fr22310110112.

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Cryopreservation of gametes and gonadal tissue is nowadays primarily accomplished through vitrification. Variables such as cooling rate, viscosity and volume of vitrification solution are critical in gamete vitrification. In addition, sample size and stepwise exposure are also crucial for gonadal tissue vitrification. Recently a class of cryodevices has been developed to reduce the volume of vitrification solution so as to achieve higher cooling rates. Vitrification devices are classified as "open" or "closed" depending on whether the medium comes into direct contact with liquid nitrogen during the process. Examples of the open cryodevices for gamete vitrification are Cryotop, Cryolock, open pulled straw (OPS), etc., and closed devices are Vitrisafe, CryoTip, and high security vitrification kit. Similarly, for tissue vitrification open cryodevices used are needles, cryovials and closed devices used are Cryotissue, ovarian tissue cryosystem, etc. Among all the gamete cryodevices, Cryotop is unique and the best-selling micro-volume storage device. Use of this device has resulted in the highest number of babies born after embryo or oocyte vitrification. Another novel device, Kitasato vitrification system, is a vitrification solution absorber, which is similar to Cryotop but differs in one way, as it possesses a porous membrane that absorbs extra solution from the gamete. This review provides an update on the recent use of cryodevices for gamete and gonadal tissue vitrification.

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Widjiati, Widjiati, Epy Muhammad Luqman, and Portia Sumarsono. "Comparison of Morula and Blastula Embryo Vitrification by Using Cryoprotectant Ethylene Glycol, Propanediol, DMSO and Insulin Transferrin Selenium." KnE Life Sciences 3, no. 6 (2017): 205. http://dx.doi.org/10.18502/kls.v3i6.1129.

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Vitrification is freezing method with low temperature (-196ºC) using high concentrations of cryoprotectants with a view to preventing the formation of ice crystals that can damage cells and decrease the viability of the embryo blastomeres. Embryos post warming which has low viability when transferred to a recipient will decrease the pregnancy rate. Intracellular cryoprotectants used in vitrification is ethylene glycol, propanediol, or DMSO. The third type of cryoprotectants has different capacities to protect the morula and blastocyst stage embryos. This study aims to decide the exact type of cryoprotectants in protecting the morula and blastocyst stage embryos when vitrification process. Research methods were divided into three groups of cryoprotectants that group treatment 1 (P1): Ethylene Glycol 30% + Sucrose 1 M + Insulin Transferrin Selenium 15 mL, group treatment 2 (P2): Propanediol 30% + Sucrose 1 M + Insulin Transferrin Selenium 15 mL, treatment Group 3 (P3): DMSO 30% + Sucrose 1 M + Insulin Transferrin Selenium 15 mL. The data obtained were analyzed by one-way ANOVA. Results of research that use Propanediol at the morula stage embryo vitrification is not significantly different from the Ethylene glycol but significantly different from DMSO. Then use Ethylene Glycol at the blastocyst stage embryo vitrification significantly different with Propanediol and DMSO and DMSO Propanediol but usage is no different. The conclusion of this study is Propanediol used as cryoprotectants in the vitrification process morula stage embryos, while ethylene glycol used as cryoprotectants the blastocyst stage embryo vitrification process.Keywords: vitrification; ethylene glycol; propanediol; DMSO; morula; blastocyst

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10

Odagaki, Takashi. "Non-Ergodicity and Non-Gaussianity in Vitrification Process." Progress of Theoretical Physics Supplement 126 (1997): 9–12. http://dx.doi.org/10.1143/ptps.126.9.

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Odagaki, T. "Non-Ergodicity and Non-Gaussianity in Vitrification Process." Progress of Theoretical Physics Supplement 126 (May 16, 2013): 9–12. http://dx.doi.org/10.1143/ptp.126.9.

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12

Blatter, A., N. Koch, and U. Kambli. "The process of spontaneous vitrification evaluated by calorimetry." Journal of the Less Common Metals 145 (December 1988): 81–88. http://dx.doi.org/10.1016/0022-5088(88)90264-0.

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13

Chang, Ching-Chien, Daniel B. Shapiro, and Zsolt Peter Nagy. "The effects of vitrification on oocyte quality." Biology of Reproduction 106, no. 2 (2021): 316–27. http://dx.doi.org/10.1093/biolre/ioab239.

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Abstract Vitrification, is an ultra-rapid, manual cooling process that produces glass-like (ice crystal-free) solidification. Water is prevented from forming intercellular and intracellular ice crystals during cooling as a result of oocyte dehydration and the use of highly concentrated cryoprotectant. Though oocytes can be cryopreserved without ice crystal formation through vitrification, it is still not clear whether the process of vitrification causes any negative impact (temperature change/chilling effect, osmotic stress, cryoprotectant toxicity, and/or phase transitions) on oocyte quality, which translates to diminished embryo developmental potential or subsequent clinical outcomes. In this review, we attempt to assess the technique’s potential effects and the consequence of these effects on outcomes.

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14

Yang, Yanzhou, Jie Chen, Hao Wu, et al. "The Increased Expression of Connexin and VEGF in Mouse Ovarian Tissue Vitrification by Follicle Stimulating Hormone." BioMed Research International 2015 (2015): 1–13. http://dx.doi.org/10.1155/2015/397264.

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Ovarian follicular damages were caused by cryoinjury during the process of ovarian vitrification and ischemia/reperfusion during the process of ovarian transplantation. And appropriate FSH plays an important role in antiapoptosis during ovarian follicle development. Therefore, in this study, 0.3 IU/mL FSH was administered into medium during mouse ovarian cryopreservation by vitrification to ascertain the function of FSH on ovarian vitrification and avascular transplantation. The results suggested that the expressions of Cx37, Cx43, apoptotic molecular caspase-3, and angiogenesis molecular VEGF were confirmed using immunohistochemistry, western blotting, and real-time PCR, and the results suggested that the treatment with FSH remarkably increased the number of morphologically normal follicles in vitrified/warmed ovaries by upregulating the expression of Cx37, Cx43, VEGF, and VEGF receptor 2, but downregulating the expression of caspase-3. In addition, the vitrified/warmed ovaries were transplanted, and the related fertility was analyzed, and the results suggested that the fertility, neoangiogenesis, and follicle reserve were remarkably increased in the FSH administrated group. Taken together, administration of 0.3 IU/mL FSH during ovarian cryopreservation by vitrification can maintain ovarian survival during ovarian vitrification and increases the blood supply with avascular transplantation via upregulation of Cx43, Cx37, and VEGF/VEGFR2, as well as through its antiapoptotic effects.

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Campbell, Lia H., and Kelvin G. M. Brockbank. "Development of a Vitrification Preservation Process for Bioengineered Epithelial Constructs." Cells 11, no. 7 (2022): 1115. http://dx.doi.org/10.3390/cells11071115.

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The demand for human bioengineered tissue constructs is growing in response to the worldwide movement away from the use of animals for testing of new chemicals, drug screening and household products. Presently, constructs are manufactured and delivered just in time, resulting in delays and high costs of manufacturing. Cryopreservation and banking would speed up delivery times and permit cost reduction due to larger scale manufacturing. Our objective in these studies was development of ice-free vitrification formulations and protocols using human bioengineered epithelial constructs that could be scaled up from individual constructs to 24-well plates. Initial experiments using single EpiDerm constructs in vials demonstrated viability >80% of untreated control, significantly higher than our best freezing strategy. Further studies focused on optimization and evaluation of ice-free vitrification strategies. Vitrification experiments with 55% (VS55) and 70% (VS70) cryoprotectant (CPA) formulations produced constructs with good viability shortly after rewarming, but viability decreased in the next days, post-rewarming in vitro. Protocol changes contributed to improved outcomes over time in vitro. We then transitioned from using glass vials with 1 construct to deep-well plates holding up to 24 individual constructs. Construct viability was maintained at >80% post-warming viability and >70% viability on days 1–3 in vitro. Similar viability was demonstrated for other related tissue constructs. Furthermore, we demonstrated maintenance of viability after 2–7 months of storage below −135 °C.

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Liu, Yue, Andy Lin, Terrence R. Tiersch, and William Todd Monroe. "A 3D Printed Vitrification Device for Storage in Cryopreservation Vials." Applied Sciences 11, no. 17 (2021): 7977. http://dx.doi.org/10.3390/app11177977.

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Sperm cryopreservation by vitrification is a promising approach for small-bodied animals such as zebrafish (Danio rerio). However, most vitrification tools adopted in aquatic research were initially designed for applications other than sperm (such as human embryo freezing) and, thus, pose challenges for adoption to sperm vitrification. Three-dimensional (3D) printing combined with open hardware sharing is an emerging strategy to address challenges in the development of cryopreservation tools. The goal of this study was to develop a 3D printed Vitrification Device for Cryo-Vials (VDCV) that can be integrated with the existing vial storage systems. The VDCV combined the vitrification and handling components to achieve functions of sample handling, vitrification, storage, and identification. The vitrification component featured a base, a stem, and a loop. A total of 36 configurations with various loop lengths (8, 10, and 12 mm); loop widths (2.0, 2.5, 3.0, and 3.5 mm); and support structures (open, transverse, and axial) of the VDCD prototypes were designed, fabricated, and tested. Device handling orientations (horizontal and vertical holding angles prior to and during freezing) were also investigated. Computer simulations estimated that the cooling rate of the samples ranged from 0.6–1.5 × 105 °C/min in all the configurations. Prior to freezing, loops with axial supports produced a minimum of 92% film retention. The overall trends of full vitrification occurrence were observed: horizontal plunging > vertical plunging, and axial support > transverse support and open loop. A loop length of 8 mm had the highest overall vitrification occurrence (86–100%). No significant differences (p = 0.6584) were shown in a volume capacity (5.7–6.0 µL) among the three supporting configurations. A single unit of VDCV can provide loading efficiencies of about 6 × 107 sperm/vial, pooling of samples from 3–6 males/vial, and fertilization for 1800 eggs/vial. The VDCV are low-cost (<$0.5 material cost per unit) and can be customized, standardized, securely labeled, and efficiently stored. The prototypes can be accessed by user communities through open-fabrication file sharing and fabricated with consumer-level 3D printers, thus facilitating community-level standardization.

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Trifunović, Vanja. "Vitrification as a method of soil remediation." Zastita materijala 62, no. 3 (2021): 166–79. http://dx.doi.org/10.5937/zasmat2103166t.

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Various types of contaminated soil and hazardous waste that have a negative impact on the environment and human health can be treated with the vitrification process. This process is based on thermal treatment of contaminated soil or waste at high temperatures, with the addition of additives, whereby the soil/waste melts and a stable glass is formed. The resulting glass and glass-ceramic products have good mechanical resistance, chemically are resistant and immobilize contaminants, thus preventing their further negative impact on the environment. This paper presents a literature review of the vitrification process of different types of contaminated soil and hazardous waste.

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Lan, Tianyang, Kang Zhang, Feifei Lin, et al. "Effects of MICU1-Mediated Mitochondrial Calcium Uptake on Energy Metabolism and Quality of Vitrified-Thawed Mouse Metaphase II Oocytes." International Journal of Molecular Sciences 23, no. 15 (2022): 8629. http://dx.doi.org/10.3390/ijms23158629.

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Background: Oocyte vitrification has been widely used in the treatment of infertility and fertility preservation. However, vitrification-induced mitochondrial damage adversely affects oocyte development. Several studies have reported that mitochondrial calcium uptake protein 1 (MICU1) regulates the uptake of mitochondrial calcium by the mitochondrial calcium uniporter (MCU) and subsequently controls aerobic metabolism and oxidative stress in mitochondria, but research considering oocytes remains unreported. We evaluated whether the addition of MICU1 modulators enhances mitochondrial activity, pyruvate metabolism, and developmental competence after warming of MII oocytes. Methods: Retrieved MII oocytes of mice were classified as vitrified or control groups. After thawing, oocytes of vitrified group were cultured with or without DS16570511 (MICU1 inhibitor) and MCU-i4 (MICU1 activator) for 2 h. Results: Mitochondrial Ca2+ concentration, pyruvate dephosphorylation level, and MICU1 expression of MII oocytes were significantly increased after vitrification. These phenomena were further exacerbated by the addition of MCU-i4 and reversed by the addition of DS16570511 after warming. However, the mitochondrial membrane potential (MMP) and adenosine triphosphate (ATP) in vitrified-warmed MII oocytes drop significantly after vitrification, which was improved after MCU-i4 treatment and decreased significantly after DS16570511 treatment. The vitrification process was able to elicit a development competence reduction. After parthenogenetic activation, incubation of the thawed oocytes with MCU-i4 did not alter the cleavage and blastocyst rates. Moreover, incubation of the thawed oocytes with DS16570511 reduced the cleavage and blastocyst rates. Conclusions: MICU1-mediated increasing mitochondrial calcium uptake after vitrification of the MII oocytes promoted the pyruvate oxidation, and this process may maintain oocyte development competence by compensating for the consumption of ATP under stress state.

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Marco-Jiménez, F., L. Casares-Crespo, and J. S. Vicente. "Porcine oocyte vitrification in optimized low toxicity solution with open pulled straws." Zygote 22, no. 2 (2012): 204–12. http://dx.doi.org/10.1017/s0967199412000524.

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SummaryOne of the greatest challenges for reproductive cryobiologists today is to develop an efficient cryopreservation method for human and domestic animal oocytes. The objective of the present study was to optimize a low toxicity solution called VM3 to vitrify porcine oocytes using an open pulled straw (OPS) device and to evaluate the effects on viability, chromosomal organization and cortical granules distribution. Two experiments were conducted in this study. Firstly, we determined the minimum concentration of cryoprotectant present in the VM3 solution required (7.6 M) for vitrification using an OPS device. The appearance of opacity was observed when using a cooling solution at –196°C; no observable opacity was noted as vitrification. In addition, the ultrastructure of oocytes in VM3 or VM3 optimized solution was examined using cryo-scanning electron microscopy. The minimum total cryoprotectant concentration present in VM3 solution necessary for apparent vitrification was 5.6 M when combined with use of an OPS device. Use of both vitrification solutions showed a characteristic plasticized surface. In the second experiment, the relative cytotoxicity of vitrification solutions (VM3 and VM3 optimized) was studied. Oocyte viability, chromosomal organization and the cortical granules distribution were assessed by fluorescent stain. After warming, oocyte survival rate was similar to that of fresh oocytes. The vitrification process significantly reduced correct chromosomal organization and cortical granules distribution rates compared with the fresh oocytes group. However, correct chromosomal organization and cortical granules distribution rates did not differ among oocytes placed in different vitrification solutions. In conclusion, our data demonstrated that the VM3 solution can be optimized and that reduction in concentration to 5.6 M enabled vitrification of oocytes with an OPS device, however use of the VM3 optimised solution had no beneficial effect on vitrification of porcine oocytes.

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Deptula, Andrzej, Magdalena Milkowska, Wieslawa Lada, et al. "Vitrification of Nuclear Wastes by Complex Sol-Gel Process." Advanced Materials Research 518-523 (May 2012): 3216–20. http://dx.doi.org/10.4028/www.scientific.net/amr.518-523.3216.

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For synthesis of silica glasses designed to contain high-level nuclear wastes，a patented complex sol-gel process has been used. Surrogates of the nuclear waste elements Cs, Sr, Co, and Nd (generically denoted Me) were used. Gels in the forms of powders and sintered compacts were prepared by hydrolysis and polycondensation of tetraethoxide/Me nitrate solutions, which contained ascorbic acid as a catalyst. Transformation to final products was studied by thermogravimetric analysis, infrared spectroscopy, and X-ray diffraction. Preliminary testing of Me leaching was also completed in water. Most of the final products were porous; only a single dense form was resistant to leaching.

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Langerman, M. A., and R. J. MacKinnon. "Scaling considerations for modelling the in situ vitrification process." Applied Mathematical Modelling 15, no. 10 (1991): 542–49. http://dx.doi.org/10.1016/0307-904x(91)90056-u.

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Hoang, V. V. "Atomic mechanism of vitrification process in simple monatomic nanoparticles *." European Physical Journal D 61, no. 3 (2011): 627–35. http://dx.doi.org/10.1140/epjd/e2011-10651-1.

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Ševelová, Helena, and Miloslava Lopatářová. "Closed system for bovine oocyte vitrification." Acta Veterinaria Brno 81, no. 2 (2012): 201–6. http://dx.doi.org/10.2754/avb201281020201.

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The aim of our study was to develop a vitrification carrier for bovine oocyte cryopreservation. The carrier was to be cheap enough, elementary in its construction and meet contemporary requirements for a safe closed system. In a closed system, a cell is prevented from direct exposure to liquid nitrogen, thus minimizing the risk of cross-contamination. Furthermore, two questions regarding the proper vitrification technique were resolved: if it is necessary to partially denude the oocytes before the vitrification process or whether intact cumulus oocyte complexes should be frozen; and if it is more advantageous to preheat the vitrification solutions to female body temperature (39 °C) or to keep them at room temperature. Our results show that it is better to partially denude the oocytes prior to vitrification because cryopreserved intact cumulus oocyte complexes often proved dark, non-homogeneous or fragmented cytoplasm after warming, with many of them having visibly widened perivitelline spaces or fractured zonae pellucidae as a result of extensive damage during vitrification. Consequently, intact cumulus oocyte complexes showed significantly lower numbers of cleavage stage embryos on Day 3 compared to partially denuded oocytes (7.4% and 26%, respectively). On the other hand, the survival rate and following development of fertilized oocytes in preheated vitrification solution were equal to results reached at room temperature conditions. In conclusion, results achieved with the newly developed carrier were comparable to previously published studies and therefore they could be recommended for common use.

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Madrid Gaviria, Stephania, Sergio A. Morado, Albeiro López Herrera, et al. "Resveratrol supplementation promotes recovery of lower oxidative metabolism after vitrification and warming of in vitro-produced bovine embryos." Reproduction, Fertility and Development 31, no. 3 (2019): 521. http://dx.doi.org/10.1071/rd18216.

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Although vitrification is the current method of choice for oocyte and embryo cryopreservation, it may have detrimental effects on reduction–oxidation status and mitochondrial activity. The aim of this study was to evaluate the effect of supplementing invitro culture (IVC) media and/or vitrification solutions with the antioxidant resveratrol on active mitochondria, mitochondrial superoxide production and lipid peroxidation. Abattoir-derived oocytes were matured and fertilised invitro using standard procedures. Following IVF (21h later), zygotes were cultured in IVC medium supplemented with 0 or 0.5µM resveratrol. On Day 7, blastocysts were vitrified using the Cryotech Vitrification Kit (Cryo Tech Laboratory) with or without 0.5µM resveratrol. After warming, active mitochondria, mitochondrial superoxide production and lipid peroxidation were evaluated using Mito Tracker Green FM, MitoSOX Red and BODIPY581/591 C11 staining respectively. The vitrification–warming process significantly increased active mitochondria and mitochondrial superoxide production in bovine embryos (P&lt;0.05, ANOVA). The addition of 0.5µM resveratrol to the IVC medium or vitrification solutions significantly attenuated the increase in active mitochondria (P&lt;0.05), but not in mitochondrial superoxide production, whereas embryos cultured and vitrified with resveratrol showed the highest values for both parameters (P&lt;0.05). Regarding lipid peroxidation, no significant differences were detected between treatments. In conclusion, resveratrol supplementation of IVC medium or vitrification solutions contributes to recovery of an embryo’s ‘quieter’ state (i.e. lower oxidative metabolism) after vitrification. However, supplementation of both solutions with resveratrol seemed to have a pro-oxidant effect.

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Nowok, Andrzej, Piotr Kuś, Mateusz Dulski, et al. "Role of intermolecular interactions and conformational changes in the polymorphism and vitrification process of 2,2′′-bis-substituted para-terphenyls." CrystEngComm 22, no. 18 (2020): 3164–78. http://dx.doi.org/10.1039/d0ce00351d.

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Lin, Chiahsin, Wen-Chung Hsieh, Kanokpron Loeslakwiboon, Cheng-Liang Huang, Ting-Chun Chen, and Sujune Tsai. "Refined Techniques for Enabling Long-Term Cryo-Repository Using Vitrification and Laser Warming." Bioengineering 10, no. 5 (2023): 605. http://dx.doi.org/10.3390/bioengineering10050605.

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Vitrification and ultrarapid laser warming are crucial for the cryopreservation of animal embryos, oocytes, and other cells of medicinal, genetic, and agricultural value. In the present study, we focused on alignment and bonding techniques for a special cryojig that combines a jig tool and jig holder into one piece. This novel cryojig was used to obtain a high laser accuracy of 95% and a successful rewarming rate of 62%. The experimental results indicated that our refined device improved laser accuracy in the warming process after long-term cryo-storage through vitrification. We anticipate that our findings will lead to cryobanking applications that use vitrification and laser nanowarming to preserve cells and tissues from a wide range of species.

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W Lestari, Silvia, Nurin N. Fitriyah, and Ria Margiana. "An Update of Oocyte Vitrification: A Modification of Sucrose and Trehalose as Extracellular Cryoprotectant." Biomedical and Pharmacology Journal 11, no. 1 (2018): 209–14. http://dx.doi.org/10.13005/bpj/1365.

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As well as the development of assisted reproductive technology (ART), as the current treatment of woman who failed in achieving pregnancy, the development of an advance vitrification method also grows rapidly. The successful of oocyte vitrification depends on the type and the concentration of cryoprotectant. This study was addressed to elaborate empirical evidence and recent studies of sucrose and trehalose as an extracellular CPA with the aim of achieving the success of oocyte vitrification. Several researchers in agreement that trehalose, as extracellular cryoprotectant, also has a role as intracellular cryoprotectant by microinjection with high survival rates as the outcome. Moreover, the combination of sucrose or trehalose as an extracellular cryoprotectant and others intracellular cryoprotectant have different survival rates which might occur because of the differences between the composition and concentration of sucrose or trehalose. The appropriate type and concentration of sugar as an extracellular cryoprotectant for oocyte cryopreservation are sucrose or trehalose in 0.5M concentration. Nevertheless, it requires further study to optimize oocyte vitrification process.

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Su, Fengmin, Yiming Fan, Chi Zhang, Yifan Wang, Yanyang Wang, and Benli Peng. "Vitrification by Transient Vacuum Flashing Spray Cooling of Liquid Nitrogen." Cryoletters 43, no. 3 (2022): 167–74. http://dx.doi.org/10.54680/fr22310110212.

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BACKGROUND: The transient vacuum flashing spray cooling of liquid nitrogen (LN2 ) on a microstructured surface can provide ultra-fast cooling rate and may improve cell survival rates. OBJECTIVE: To utilize flashing spray cooling of LN2 instead of film boiling to improve further cell vitrification. METHOD: This study analyzed the effects of the three key parameters (flow rate of liquid nitrogen, ambient pressure, and spray distance) on the cooling process by experimentation. RESULTS: The experimental results showed that the vacuum flashing spray cooling of LN2 can gain higher cooling rates than that achieved by film boiling in conventional vitrification methods. The three parameters all affected the vacuum flash evaporation spray cooling of LN2, and their effect trends were not monotonous but followed a parabolic trend that increased and then decreased. That is, the three parameters all have optimum values to the cooling process. CONCLUSION: Vacuum flash evaporation spray cooling can develop the ultra-fast cooling rates needed to enhance cell vitrification.

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Roth, G., and S. Weisenburger. "Vitrification of high-level liquid waste: glass chemistry, process chemistry and process technology." Nuclear Engineering and Design 202, no. 2-3 (2000): 197–207. http://dx.doi.org/10.1016/s0029-5493(00)00358-7.

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Isachenko, V., I. Lapidus, E. Isachenko, et al. "Human ovarian tissue vitrification versus conventional freezing: morphological, endocrinological, and molecular biological evaluation." REPRODUCTION 138, no. 2 (2009): 319–27. http://dx.doi.org/10.1530/rep-09-0039.

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Cryopreservation as a process can be divided into two methods: conventional freezing and vitrification. The high effectiveness of vitrification in comparison with conventional freezing for human oocytes and embryos is shown, whereas data on human ovarian tissue are limited. The aim of this study was to compare the safety and effectiveness of conventional freezing and vitrification of human ovarian tissue. Ovarian tissue fragments from 15 patients were transported to the laboratory within 22–25 h in a special, isolated transport box that can maintain a stable temperature of between 5 and 8 °C for 36 h. Small pieces of ovarian tissue (0.3–1×1–1.5×0.7–1 mm) were randomly distributed into three groups: group 1, fresh pieces immediately after receiving transport box (control); group 2, pieces after vitrification; and group 3, pieces after conventional freezing. After thawing, all the pieces were culturedin vitro. The viability and proliferative capacity of the tissue byin vitroproduction of hormones, development of follicles, and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) gene expression after culture were evaluated. A difference between freezing and vitrification was not found in respect to hormonal activity and follicle quality. The supernatants showed 17-β estradiol concentrations of 365, 285, and 300 pg/ml respectively, and progesterone concentrations of 3.82, 1.99, and 1.95 ng/ml respectively. It was detected that 95, 80, and 83% follicles respectively were morphologically normal. The molecular biological analysis, however, demonstrated that theGAPDHgene expression in ovarian tissue after vitrification was dramatically decreased in contrast to conventional freezing. For cryopreservation of human ovarian tissue, conventional freezing is more promising than vitrification, because of higher developmental potential.

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31

Fu, Xufeng, Yaping Yan, Shanshan Li, et al. "Vitrification of Rhesus Macaque Mesenchymal Stem Cells and the Effects on Global Gene Expression." Stem Cells International 2017 (2017): 1–14. http://dx.doi.org/10.1155/2017/3893691.

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Mesenchymal stem cells (MSCs) are one of the most promising adult stem cells for clinical application in a cell therapy. The development of large-scale cryopreservation techniques, such as vitrification, for MSCs is a prerequisite for clinical therapies. Dimethyl sulfoxide (DMSO) and ethylene glycol (EG) are two types of cryoprotectants widely used for cell vitrification. However, the effects of DMSO and EG on the biological characteristics and transcriptome profiles of MSCs after cryopreservation remain unknown. In the present study, the viability, immunophenotype of cell surface markers, proliferation, differentiation potency, and global gene expression of rhesus macaque bone marrow-derived MSCs vitrified using DMSO and EG were studied. The results showed that vitrification did not affect the morphology, surface markers, and differentiation of the MSCs, and compared to DMSO, EG better protected cell viability and proliferation. Most importantly, vitrification resulted in changes in a large number of transcripts of MSCs either preserved using DMSO or EG. This report is the first to examine the effects of DMSO and EG on global gene expression in stem cells. These results will be beneficial to understanding the biological process involved in MSC vitrification and will contribute to improving cryopreservation protocols that maintain transcriptomic identity with high cryosurvival for preclinical research and clinical long-term storage.

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32

Li, Yong, Xue Gang Liu, and Jin Chen. "The Application Research of Concentration & Denitration Technology in Advanced Reprocessing Process." Advanced Materials Research 560-561 (August 2012): 637–43. http://dx.doi.org/10.4028/www.scientific.net/amr.560-561.637.

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The proper management of spent fuel arising from nuclear power production is a key issue for the sustainable development of nuclear energy. While conventional reprocessing process, PUREX process, was successful to recover uranium and plutonium, in recent years some countries have turned to focus on advanced reprocessing process, which features of partitioning of minor actinides (MA) and long-lived fission products(LLFP). Most advanced reprocessing processes under development involve new extractants and additional extraction cycles. In China, TRPO extraction process has been developed to partition MA/LLFP from high-level liquid waste(HLLW) since early 1980’s. In parallel to R&D work on separation technologies, studies on concentration & denitration process have been evolved to prepare feed solutions to suit qualifications of extraction. Industrially, concentration & denitration is the internationally recognized standard to treat HLLW released from PUREX before vitrification. It enables to minimize the volume of interim storage, to restrain the corrosion of storage tank, to recover nitric acid in HLLW and to reduce the required evaporation duty of the vitrification process. Generally, the constitution of concentrated HLLW has little impact on the following vitrification process. But when concentration & denitration acts as pretreatment process of partitioning, the composition of actinides, fission products, and nitric acid in concentrated HLLW solution plays significant role in extraction process. A series of technical issues relevant to the connection between concentration ﹠denitration and extractions should be solved. This paper describes current status of concentration & denitration technology utilized in industry and under reprocessing plants. The specific separation requirements in advanced reprocessing process and challenges to apply concentration & denitration process are addressed. Besides, concentration & denitration process was tested in laboratory to adjust feed solutions for TRPO and Cyanex301 partitioning. Results demonstrate its promising prospect in advanced reprocessing process.

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33

Nakahara, Keisuke. "Vitrification Process for Recovery of Phosphorus from Sewage Sludge Ash." RESOURCES PROCESSING 50, no. 2 (2003): 68–73. http://dx.doi.org/10.4144/rpsj1986.50.68.

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Kikuchi, Ryunosuke. "Vitrification Process for Treatment of Sewage Sludge and Incineration Ash." Journal of the Air & Waste Management Association 48, no. 11 (1998): 1112–15. http://dx.doi.org/10.1080/10473289.1998.10463766.

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35

Egorov, E. A., and V. V. Zhizhenkov. "Influence of Mechanical Vitrification on Flexible-Chain Polymer Drawing Process." International Journal of Polymeric Materials 22, no. 1-4 (1993): 41–47. http://dx.doi.org/10.1080/00914039308012056.

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36

Odagaki, T., J. Matsui, and M. Higuchi. "Dynamical characteristics of the vitrification process of an ideal system." Journal of Physics: Condensed Matter 10, no. 49 (1998): 11491–98. http://dx.doi.org/10.1088/0953-8984/10/49/035.

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37

Ranganathan, S., and P. Ramachandra Rao. "Thermodynamic modelling of the spontaneous vitrification process using transformation diagrams." Calphad 34, no. 4 (2010): 387–92. http://dx.doi.org/10.1016/j.calphad.2010.07.004.

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38

Iwaszko, Józef, Monika Zajemska, Anna Zawada, Stanisław Szwaja, and Anna Poskart. "Vitrification of environmentally harmful by-products from biomass torrefaction process." Journal of Cleaner Production 249 (March 2020): 119427. http://dx.doi.org/10.1016/j.jclepro.2019.119427.

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39

Yoshioka, M., S. Torata, J. Igarashi, T. Takahashi, and M. Horie. "Glass melter and process development for PNC Tokai vitrification facility." Waste Management 12, no. 1 (1992): 7–16. http://dx.doi.org/10.1016/0956-053x(92)90003-2.

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40

Faizah, Zakiyatul, R. Haryanto Aswin, Hamdani Lunardhi, and Widjiati Widjiati. "Hyaluronan Expression on Vitrified Oocytes Before and After In Vitro Maturation (EKSPRESI HYALURONAN PADA OOSIT YANG DIVITRIFIKASI SEBELUM DAN SESUDAH MATURASI IN VITRO)." Jurnal Veteriner 19, no. 1 (2018): 71. http://dx.doi.org/10.19087/jveteriner.2018.19.1.71.

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Oocyte vitrification is a major challenge in assisted reproductive technology. Oocyte vitrification with cumulus cells provide benefits in the process of maturation and fertilization. Vitrification leads to rapid temperature changes, therefore the decreasing in temperature could damage the cells even when the morphology was normal. Vitrification of mature oocytes is common because of its low sensitiveness towards low temperatures than immature oocytes. The aim of the research was to compare the effect of vitrification before and after in vitro maturation to the expression of hyaluronan. Maturation was operated in medium TC 50 ?L in CO2 incubators for 24 hours. Vitrification started with washing oocyte in PBS basic medium supplemented with 20% serum for 1-2 minutes, then in equilibration medium PBS + 20% serum + 10% ethylene glycol for 10-14 minutes, then transferred to 20% serum + PBS + 0.5 M sucrose + 15% ethylene glycol + PROH 15% for 25-30 seconds. Thawing was processed by submerging the oocytes in the media: 1). PBS + 20% serum + 0.5 M sucrose (K1); 2) PBS + 20% serum + 0.25 M sucrose (K2); and 3).PBS + 20% serum + 0.1 M sucrose (K3). Immunocytochemical stain was performed to evaluate the hyaluronan expression. Remmele scale index (Immunoreactive score, IRS) was used to read the result. There was no differences of hyaluronan expression in oocyte and cumulus group of K1, K2 and K3 at p< 0.05, statistically. We concluded that there was no difference of hyaluronan expression on oocyte and cumulus between vitrified oocyte of pre and post in vitro maturation which indicated that oocyte could be vitrified in the immature and mature state.

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41

Sayenko, Sergii, Volodymyr Shkuropatenko, Yevhenii Svitlychnyi, et al. "Vitrification of a Simulator of Vat Residues from Liquid Radioactive Waste." East European Journal of Physics, no. 1 (March 2, 2023): 94–101. http://dx.doi.org/10.26565/2312-4334-2023-1-11.

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The study on the posibility of the use of the optimal glass compositions for vitrification of an imitator of vat residues of liquid radioactive waste from nuclear power plants with VVER-1000 reactors was carried out. The main process parameters such as vitrification temperature, strength, corrosion resistance, absence of crystalline phases, minimization of glass-forming additives and inclusion the maximum amount of waste were analyzed. It has been established that the melting temperature of lead-borosilicate glass matrices was 1150 °C, which satisfies the requirements for vitrification of low- and medium-level waste. The ultimate compressive strength of the obtained samples of glass matrices was 136.0 MPa. In addition, it has been shown that lead-borosilicate glass matrices are the most resistant to leaching. The cesium leaching rate was 1.5·10-5 g/cm2·day.

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42

Wang, Mengying, Plamen Todorov, Wanxue Wang, et al. "Cryoprotectants-Free Vitrification and Conventional Freezing of Human Spermatozoa: A Comparative Transcript Profiling." International Journal of Molecular Sciences 23, no. 6 (2022): 3047. http://dx.doi.org/10.3390/ijms23063047.

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Introduction: Spermatozoa cryopreservation is an important technique to preserve fertility for males. This study aimed at exploring the stability of epigenetics information in human spermatozoa, manipulated by two different technologies, freezing and vitrification. Methods: Spermatozoa samples were distributed into three groups: 1. Fresh spermatozoa (control group), 2. Frozen spermatozoa, 3. Vitrified spermatozoa. Epigenetic differences of fresh and cryopreserved spermatozoa were evaluated using high-throughput RNA sequencing. Results: Differentially expressed genes (DEGs) in frozen (1103 genes) and vitrified (333 genes) spermatozoa were evaluated. The bioinformatical analysis identified 8 and 15 significant pathways in groups of frozen and vitrified spermatozoa, respectively. The majority of these pathways are most relevant to immune and infectious diseases. The DEGs of the fertilization process are not detected during vitrification. The freezing process induces more down-regulation of genes and is relevant to apoptosis changes and immune response. Conclusion: Cryopreservation of human spermatozoa is an epigenetically safe method for male fertility preservation. Cryoprotectant-free vitrification can induce more minor biological changes in human spermatozoa, in comparison with conventional freezing.

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43

Matrosov, Andrey, Arkady Soloviev, Elena Ponomareva, et al. "Finite Element Modeling of Crystallization with Temperature Jump to Improve Cryopreservation of Fish Germ Cells." Processes 12, no. 2 (2024): 413. http://dx.doi.org/10.3390/pr12020413.

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This article is devoted to the further development of a viable technology for low-temperature cryopreservation of reproductive cells of sturgeon fish using acoustic–mechanical fields and intelligent control of the freezing process. Before vitrification begins, the piezoactuator acts on a mixture of cryoprotectant and reproductive cells. This promotes intensive mixing of the cryoprotector and its diffusion through the cell membrane. When vitrification is carried out directly, a phase transition phenomenon is observed, accompanied by crystal formation. This article presents a new mathematical model describing this process as developed by the authors. The corresponding boundary conditions are formulated. Numerical experiments were carried out using the finite element method. It has been established that during vitrification without the use of a cryoprotectant, a sharp temperature jump is observed at the front of the crystalline formation boundary. The use of a cryoprotectant leads to a slowdown in the process of crystal formation, that is, to a weakening of the effect of one of the most important cryoprotective factors. The comparison with full-scale experiments showed qualitative agreement with the experimental results, which indicates the adequacy of the proposed model. The results obtained can be used in the future during the vitrification process and the evaluation of the quality of cryofreezing. The application of a new methodological approach to methods of long-term preservation at low temperatures of the genetic and reproductive material of hydrobionts using acoustic and mechanical effects and an intelligent control module opens up great opportunities for the creation of new cost-effective biotechnologies that make it possible to make the transition to a new type of aquatic farms, increase the stability of aquaculture, in general, to make environmental protection measures to save rare and endangered species more effective.

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44

Do, V. H., S. Catt, J. E. Kinder, S. Walton, and A. W. Taylor-Robinson. "Vitrification of in vitro-derived bovine embryos: targeting enhancement of quality by refining technology and standardising procedures." Reproduction, Fertility and Development 31, no. 5 (2019): 837. http://dx.doi.org/10.1071/rd18352.

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Bovine invitro fertilisation technology has been widely exploited in commercial settings. The majority of invitro-derived cattle embryos are transferred into recipient cows as recently collected (i.e. ‘fresh’) embryos due to the lack of a reliable cryopreservation method that results in favourable pregnancy rates following transfer of thawed embryos. This is a primary reason for the poor industry uptake of this extreme temperature freezing process. Numerous investigations into vitrification have revealed the importance of rapid cooling and warming rates, enhancing embryo viability after cryopreservation compared with conventional slow freezing. Those studies spawned a considerable assortment of cryovessels and diversity of procedures, delivering variable rates of success, which makes performing vitrification consistently a practical challenge. Hence, further research is required in order to both optimise and standardise vitrification methodology and to design a cryovessel that enables direct transfer of vitrified embryos to recipients after warming. In parallel with improvements in vitrification, it is important to continue to raise the quality of invitro-derived cattle embryos through modifications in laboratory culture techniques. The twin goals of methodology refinement and standardisation, leading to embryo quality enhancement, are each imperative if invitro fertilisation technology is to be adopted in the field.

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45

Vajta, Gábor. "Vitrification in human and domestic animal embryology: work in progress." Reproduction, Fertility and Development 25, no. 5 (2013): 719. http://dx.doi.org/10.1071/rd12118.

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According to the analysis of papers published in major international journals, rapidly increasing application of vitrification is one of the greatest achievements in domestic animal and especially human embryology during the first decade of our century. This review highlights factors supporting or hampering this progress, summarises results achieved with vitrification and outlines future tasks to fully exploit the benefits of this amazing approach that has changed or will change many aspects of laboratory (and also clinical) embryology. Supporting factors include the simplicity, cost efficiency and convincing success of vitrification compared with other approaches in all species and developmental stages in mammalian embryology, while causes that slow down the progress are mostly of human origin: inadequate tools and solutions, superficial teaching, improper application and unjustified concerns resulting in legal restrictions. Elimination of these hindrances seems to be a slower process and more demanding task than meeting the biological challenge. A key element of future progress will be to pass the pioneer age, establish a consensus regarding biosafety requirements, outline the indispensable features of a standard approach and design fully-automated vitrification machines executing all phases of the procedure, including equilibration, cooling, warming and dilution steps.

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46

de Mello, Fernanda, Daniel Jaen Alonso, Natália Pires Vieira Morais de Faria, et al. "Alterations in Gene Expression and the Fatty Acid Profile Impact but Do Not Compromise the In Vitro Maturation of Zebrafish (Danio rerio) Stage III Ovarian Follicles after Cryopreservation." Animals 13, no. 22 (2023): 3563. http://dx.doi.org/10.3390/ani13223563.

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The vitrification of ovarian follicles is a strategic tool that may contribute to advances in aquaculture and the conservation of many important species. Despite the difficulties inherent to the cryopreservation of oocytes, some successful protocols have been developed for different species, but little is known about the capacity of oocytes to develop after thawing. Therefore, the profiles of the reproductive pathway genes and fatty acid membrane composition during the initial stages of development were analyzed in fresh ovarian follicles and follicles after the vitrification process. There were differences in the expression of the hypothalamic–pituitary–gonad axis genes during the follicular development in the control group as well as in the vitrified group. Similarly, alterations in the composition of fatty acids were observed after vitrification. Despite this, many alterations were observed in the vitrified group; more than half of the stage III ovarian follicles were able to grow and mature in vitro. Therefore, the vitrification of ovarian follicles may impact them at molecular and membrane levels, but it does not compromise their capability for in vitro maturation, which indicates that the technique can be a strategic tool for aquaculture.

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47

Yun, Jong-Il, Reinhardt Klenze, and Jae-Il Kim. "Laser-Induced Breakdown Spectroscopy for the On-Line Multielement Analysis of Highly Radioactive Glass Melt Simulants. Part II: Analyses of Molten Glass Samples." Applied Spectroscopy 56, no. 7 (2002): 852–58. http://dx.doi.org/10.1366/000370202760171518.

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The paper presents the application of laser-induced breakdown spectroscopy (LIBS) for the on-line multielement analyses of glass melts in a vitrification process of high level liquid waste (HLLW). The third harmonic pulse of an Nd:YAG laser is used for the generation of plasma on the molten glass surface and the plasma emission is monitored by an echelle spectrometer with an intensified charge-coupled device (ICCD), which simultaneously covers the wavelength range from 200 to 780 nm. Twelve different reference HLLW glass melts with a complex composition of about 27 chemical elements are simulated on a laboratory scale, varying the HLLW component concentration. By real-time analyses of the reference glasses at 1200 °C, the analytical method is calibrated. A multivariate regression approach with partial least squares (PLS) is used for the data evaluation. The LIBS method thus calibrated is then applied for the multielement analysis of molten glass samples from the prototype vitrification plant under operation in our institute. The results underline that the LIBS method can be applied to a vitrification process for the on-line multielement analysis of highly radioactive glass melts.

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48

Fuller, D., J. Herrick, J. Graham, and J. Barfield. "42 Vitrification of invitro-produced feline embryos." Reproduction, Fertility and Development 32, no. 2 (2020): 146. http://dx.doi.org/10.1071/rdv32n2ab42.

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Preservation of feline embryos is useful in propagating endangered species, preserving valuable genetics, and supporting biomedical research. Although a wide variety of cryoprotectants (CP) and protocols are successfully used for vitrification of invitro-produced (IVP) embryos, there are often species-specific differences in viability of embryos post-warming. The purpose of this study was to evaluate the viability of IVP feline embryos after vitrification using two common CPs, propanediol (PrOH) or ethylene glycol (EG). Embryos were produced with oocytes and frozen-thawed epididymal sperm collected from local spay-neuter clinics using a published IVP protocol developed for producing domestic feline embryos. Day 7 early blastocysts (stage 5), blastocysts (stage 6), and expanded blastocysts (stage 7) were evaluated for quality (grade 1 or 2) and randomly assigned to one of three treatments: vitrification with PrOH (n=32), vitrification with EG (n=31), or control (n=47), which was allowed to continue in culture until Day 8. The vitrification protocol was as follows. The base medium for all vitrification media was a HEPES-buffered feline optimized culture medium (FOCMH). Embryos were placed in 0.5mL of equilibration medium (7.5% dimethyl sulfoxide, 7.5% PrOH or EG, 0.5M sucrose, 10% Ficoll, and 20% fetal calf serum (FCS)) for 5min at room temperature. Individual embryos were then moved to 20-μL drops of vitrification medium (15% dimethyl sulfoxide, 15% PrOH or EG, 0.5M sucrose, 10% Ficoll, and 20% FCS) at room temperature for 30s before being loaded onto Cryolock devices and plunged into liquid nitrogen. Warming was done using a 3-step process for all vitrified embryos. First, embryos were moved from liquid nitrogen directly to 0.5mL of 1M sucrose, 10% Ficoll, and 20% FCS at 37°C for 1min. Next, embryos were moved to 0.5mL of 0.5M sucrose, 10% Ficoll, and 20% FCS at 20°C for 3min. Finally, embryos were transferred to 0.5mL of FOCMH for 5min at 37°C. All warmed embryos were cultured in medium, optimized for feline embryos, with 5% FCS and evaluated for re-expansion of the blastocoele and progression in development at 24 and 48h. Results are from five replicates. Embryos vitrified in EG exhibited higher percentages of viable embryos 24h after warming (84%) than embryos vitrified in PrOH (59%; P&lt;0.05). The continued embryonic growth of viable embryos after culture for 48h showed equivalent developmental rates, at 87, 96, and 100% for control, EG-treated, and PrOH-treated embryos, respectively (P&gt;0.05). Results indicate EG is a more successful CP treatment for vitrification of feline embryos when evaluating viability 24h post-warming. We report a higher viability of embryos post-thaw than previous studies using the same CPs (Pope et al. 2012 Reprod. Domest. Anim. 47, 125). This may be due to the shorter exposure time to the CPs we used during the vitrification process. We conclude that EG and PrOH are effective CPs for Day 7 feline IVP embryos using this protocol. Further research is needed to increase treatment numbers and evaluate pregnancy rates from embryos transferred post-warming.

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49

Gutierrez-Castillo, Emilio, Hao Ming, Brittany Foster, et al. "Effect of vitrification on global gene expression dynamics of bovine elongating embryos." Reproduction, Fertility and Development 33, no. 5 (2021): 338. http://dx.doi.org/10.1071/rd20285.

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Embryo vitrification involves exposure to high concentrations of cryoprotectants and osmotic stress during cooling and warming in the cryopreservation process. Many of these factors can potentially affect gene expression. In this study, invitro-produced bovine embryos at the blastocyst stage were subjected to vitrification. Four recipients each were used for transferring non-vitrified (n=80) and vitrified (n=80) embryos. A total of 12 non-vitrified and 9 vitrified viable day-14 (D14) embryos were recovered by uterine flushing. RNA-seq analysis of the whole embryo or isolated trophectoderm (TE) from vitrified and fresh recovered D14 embryos revealed a total of 927 and 4376 genes with changed expression in embryos and TE isolates, respectively, as a result of vitrification. In addition, we found 671 and 61 genes commonly up- or downregulated in both vitrified whole embryos and TE. Commonly upregulated pathways by vitrification included epithelial adherens junctions, sirtuin signalling, germ cell–sertoli cell junction, ATM signalling, NER and protein ubiquitination pathways. The commonly downregulated pathways included EIF2 signalling, oxidative phosphorylation, mitochondrial dysfunction, regulation of eIF4 and p70S6K signalling and mTOR signalling pathways. Our analysis identified specific pathways and implicated specific gene expression patterns affecting embryo developmental competence that are important to cryopreservation.

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50

Zakošek Pipan, Maja, Margret L. Casal, Nataša Šterbenc, Irma Virant Klun, and Janko Mrkun. "Vitrification Using Soy Lecithin and Sucrose: A New Way to Store the Sperm for the Preservation of Canine Reproductive Function." Animals 10, no. 4 (2020): 653. http://dx.doi.org/10.3390/ani10040653.

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A challenge in freezing semen for short and long-term availability is avoiding damage to intact spermatozoa caused by the freezing process. Vitrification protocols provide better results through less manipulation of semen and shorter freezing time compared to slow freezing techniques. Our research was aimed at improving vitrification methods for canine semen. Semen quality was determined in 20 ejaculates after collection. Each ejaculate was divided into eight aliquots, each with a different extender. The control extender contained TRIS, citric acid, fructose, and antibiotics. Soy lecithin and sucrose were added to the control extender at different concentrations to make up the test extenders and final concentration of 50 × 106 spermatozoa/mL. From each group, a 33 µL (1.65 × 106 spermatozoa) suspension of spermatozoa was dropped directly into liquid nitrogen and devitrified at least one week later and evaluated as before. Soy lecithin at 1% and 0.25 M sucrose added to the base vitrification media effectively preserved all sperm qualities. Our results demonstrate the effectiveness of our methods. Vitrification media containing sucrose and soy lecithin cause a minimal decline in quality of canine semen after devitrification. Furthermore, extenders used in our research did not contain egg yolk, which was replaced by soy lecithin, thus allowing for ease of shipping to other countries with strict requirements.

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