-
Cryobiology Dec 2023In order to make dry ice transportation of vitrified embryos practical, a near-equilibrium vitrification was developed using a cryoprotectant solution (EDFS10/10a), by...
In order to make dry ice transportation of vitrified embryos practical, a near-equilibrium vitrification was developed using a cryoprotectant solution (EDFS10/10a), by which mouse embryos at various stages were vitrified in a near-equilibrium environment. EDFS10/10a consisted of 10% (v/v) ethylene glycol, 10% (v/v) MeSO, 0.4 M sucrose and 24% (w/v) Ficoll PM70. This method exhibited the benefits of slow freezing and vitrification, with a low risk of osmotic injury. In this study, we investigated whether mouse oocytes are vitrifiable with EDFS10/10a in a highly dehydrated/concentrated state, and whether they can remain fertilizable and developing into embryos after vitrification. When mature mouse oocytes were vitrified in liquid nitrogen and after 4-28 days of storage at -80 °C, high survival rates were observed (88-99%). Vitrified and warmed oocytes were subjected to partial zona dissection and in vitro fertilized. The rate of 2-cell stage was 80-82%. Blastocyst formation rate was 55-70% which was similar to that of embryos derived from fresh oocytes. After the 2-cell embryos were transferred to recipient mice, the implantation and offspring rates did not differ significantly from those of embryos derived from fresh oocytes, indicating that vitrified oocytes retained the developmental ability. Therefore, it is possible to vitrify mouse oocytes in a near-equilibrium state using EDFS10/10a and conveniently transported using dry ice.
Topics: Mice; Animals; Vitrification; Cryopreservation; Dry Ice; Cryoprotective Agents; Oocytes; Blastocyst
PubMed: 37722470
DOI: 10.1016/j.cryobiol.2023.104586 -
Journal of Cell Science Nov 2019This paper describes a simple, hazard-free and inexpensive procedure that allows researchers to send cultured cells across the globe at ambient temperatures. The method...
This paper describes a simple, hazard-free and inexpensive procedure that allows researchers to send cultured cells across the globe at ambient temperatures. The method enables transit of up to 2 weeks without compromising cell recovery. Its use will assist collaborators in distant laboratories to exchange cells without using dry-ice.
Topics: Animals; Cell Culture Techniques; Cell Survival; Dry Ice; Ice; Laboratories; Rats; Time Factors
PubMed: 31578238
DOI: 10.1242/jcs.238139 -
Cryobiology Mar 2024Cryopreserved semen is routinely shipped in liquid nitrogen. Dry ice could serve as an alternative coolant, however, frozen storage above liquid nitrogen temperatures...
Cryopreserved semen is routinely shipped in liquid nitrogen. Dry ice could serve as an alternative coolant, however, frozen storage above liquid nitrogen temperatures (LN2, -196 °C) may negatively affect shelf-life and cryosurvival. In this study, we determined critical temperatures for storage of cryopreserved stallion sperm. We evaluated: (i) effects of cooling samples to different subzero temperatures (-10 °C to -80 °C) prior to storing in LN2, (ii) stability at different storage temperatures (i.e., in LN2, dry ice, -80 °C and -20 °C freezers, 5 °C refrigerator), and (iii) sperm cryosurvival during storage on dry ice (i.e., when kept below -70 °C and during warming). Furthermore, (iv) we analyzed if addition of synthetic polymers (PVP-40, Ficoll-70) modulates ice crystallization kinetics and improves stability of cryopreserved specimens. Sperm motility and membrane intactness were taken as measures of cryosurvival, and an artificial insemination trial was performed to confirm fertilizing capacity. We found that adding PVP-40 or Ficoll-70 to formulations containing glycerol reduced ice crystal sizes and growth during annealing. Post-thaw sperm viability data indicated that samples need to be cooled below -40 °C before they can be safely plunged and stored in LN2. No negative effects of relocating specimens from dry ice to LN2 and vice versa became apparent. However, sample warming above -50 °C during transport in dry ice should be avoided to ensure preservation of viability and fertility. Moreover, addition of PVP-40 or Ficoll-70 was found to increase sperm cryosurvival, especially under non-ideal storage conditions where ice recrystallization may occur.
Topics: Male; Animals; Horses; Cryopreservation; Semen; Dry Ice; Ice; Polymers; Crystallization; Ficoll; Semen Preservation; Sperm Motility; Spermatozoa; Nitrogen; Povidone
PubMed: 38295927
DOI: 10.1016/j.cryobiol.2024.104852 -
Frontiers in Microbiology 2019The standardization of collection and processing methods for rumen samples is crucial to reduce the level of errors that may affect the analysis and interpretation of...
The standardization of collection and processing methods for rumen samples is crucial to reduce the level of errors that may affect the analysis and interpretation of the data. The aim of this study was to compare two processing methods and their impacts on the microbial community composition analysis, from material that was either immediately frozen or samples that were stored as cell pellets after removing the supernatant prior to freezing. Eight rumen-fistulated Brahman steers received chloroform as an antimethanogenic compound for 21 days. Rumen fluid samples (60 mL per animal) were collected using a probe covered with two layers of cheesecloth at 3 h post feeding at day 0 prior-treatment (control period) and day 21 of treatment. One sub-set of samples were placed in dry ice and stored at -80°C (Method 1) for subsequent DNA extraction, while a second subset of samples was centrifuged, the supernatant removed and the microbial pellet and rumen contents placed in dry ice and stored at -80°C (Method 2) prior to DNA extractions. Phylogenetic based methods (Illumina Miseq) targeting the 16S rRNA gene were used to characterize the bacterial and archaeal communities from both collection methods for the control and treatment periods. The results from this study showed that the chloroform treatment was significantly different for all beta diversity measures regardless of the processing method used. Significant differences in the relative abundances of some bacteria and archaea, such as Elusimicrobia, Fibrobacteres, Lentisphaerae, Spirochaetes, and Verrucomicrobia and Methanomassiliicoccaceae, were observed at higher levels in the Method 2. These microbial populations are known to have fragile cell wall structures and are susceptible to cell lysis. Regardless of the processing method used, both identified the key microbial groups and can be used to compare the relative shifts in the rumen microbiome between treatments. However, immediately freezing samples might alter the abundance of material from species that are more readily lysed and will not be suitable for studies that aim to assign absolute abundance values to these species within the rumen.
PubMed: 31114550
DOI: 10.3389/fmicb.2019.00861 -
Materials (Basel, Switzerland) Aug 2022This article presents the results of a numerical experimental study on the simulation of the dry ice compaction process. The first part of the article presents a...
This article presents the results of a numerical experimental study on the simulation of the dry ice compaction process. The first part of the article presents a description of the material used, material models and the methodology of experimental research. In the second part, numerical and experimental study results are presented. For the purpose of comparison, a parametric method based on the residual sum of squares was used. The application of the indicated method fills the gap in the available literature as the authors are not aware of any existing data from previous studies on the method of comparing the results of numerical tests in terms of the obtained results and the change of the value of the tested parameter as a function of another variable. The results of this study can be useful in research work aimed at further development of the process of extrusion and compaction of dry ice using Drucker-Prager/Cap and modified Cam-Clay material models for instance for optimization of geometric parameters of parts and components of the main assembly of the machine used in the process of dry ice extrusion.
PubMed: 36013907
DOI: 10.3390/ma15165771 -
Journal of Fish Biology Mar 2020Larval fishes provide a valuable metric for assessing and monitoring species, populations, and ecosystem trends and condition. However, taxonomic resolution for this...
Larval fishes provide a valuable metric for assessing and monitoring species, populations, and ecosystem trends and condition. However, taxonomic resolution for this life stage is inherently problematic because of their individual sizes, limited morphological characteristics and high tissue degradation rates. There is little research on methods that rapidly preserve larval tissues for later morphological and molecular identification. The goal of this study was to test methods of rapidly killing fish embryos that maintain both morphological and molecular integrity. Rapid cooling with dry ice successfully maintained morphological and molecular integrity and may offer a simple and cost-effective approach for larval fish identification.
Topics: Animals; DNA Barcoding, Taxonomic; Dry Ice; Embryo, Nonmammalian; Fishes; Preservation, Biological
PubMed: 31893466
DOI: 10.1111/jfb.14248 -
JDS Communications Nov 2023The objective of this research was to evaluate the suitability of whey permeate powder for ice cream. Three white mixes were formulated with equivalent total solids,...
The objective of this research was to evaluate the suitability of whey permeate powder for ice cream. Three white mixes were formulated with equivalent total solids, fat, and carbohydrates, but different concentrations of lactose and added sugar. Vanilla ice creams contained either reduced lactose (RL, 3.8% lactose and 17% added sugar), standard lactose (SL, 5.8%; 15%), or high lactose (HL, 7.8%; 13%). Trained panelists evaluated 8 body and texture, and 6 flavor characteristics through 10 mo of storage. All ice creams maintained low mean scores (<4.0/15.0 cm) for crumbly, lacks freshness, nonfat dry milk flavor, and whey, and moderate mean scores (5.0-8.3/15.0 cm) for gummy, melt rate, melt viscosity, sweet, and vanilla flavor for 10 mo. In mo 1 and 10, consumers in Iowa (n = 94, n = 55) and in mo 4 and 6, consumers in Kansas (n = 44; n = 56) rated the acceptability of the ice creams. Overall acceptability, flavor, and texture acceptability for products did not significantly differ until mo 10, when HL mean scores decreased lower than SL ice cream mean scores. The lower scores are attributed to crumbly and sandy texture defects, noted by trained panelists, only for HL ice cream stored 10 mo. The research demonstrates that whey permeate powder can be used to produce ice creams of acceptable quality for up to 10 mo.
PubMed: 38045891
DOI: 10.3168/jdsc.2023-0382 -
International Journal of Emergency... Dec 2017The goal of this article was to provide an overview of the literature available on carbon dioxide intoxication. Articles were included based on their focus on medical or... (Review)
Review
The goal of this article was to provide an overview of the literature available on carbon dioxide intoxication. Articles were included based on their focus on medical or physiological effects of carbon dioxide. Studies related to decompression sickness were excluded. Mechanisms of carbon dioxide poising (both as an asphyxiant and as a toxicant) were described. Our review suggested that precautions are needed when handling dry ice or while working in confined spaces. Pre-hospital responders also need to pay attention for the possible diagnosis of CO intoxication for their own safety. When confronted with a victim, he/she should be removed from the dangerous area as fast as possible and oxygen should be administered. Without adequate treatment, victims may show acute reduced cognitive performance, respiratory failure, and circulatory arrest. Therefore, carbon dioxide poisoning is a rare but not to miss diagnosis in the emergency department.
PubMed: 28378268
DOI: 10.1186/s12245-017-0142-y -
Biomaterials Advances Aug 2022Freeze-drying is a process of choice to texture hydrogel scaffolds with pores formed by an ice-templating mechanism. Using state-of-the-art microscopies (cryo-EBSD,...
Freeze-drying is a process of choice to texture hydrogel scaffolds with pores formed by an ice-templating mechanism. Using state-of-the-art microscopies (cryo-EBSD, μCT, CLSM), this work evidences and quantifies the effect of crosslinking and ice nucleation temperature on the porous structure of thin hydrogel scaffolds freeze-dried at a low cooling rate. We focused on a polysaccharide-based hydrogel and developed specific protocols to monitor or trigger ice nucleation for this study. At a fixed number of intermolecular crosslinks per primary molecule (p = 5), the mean pore size in the dry state decreases linearly from 240 to 170 μm, when ice nucleation temperature decreases from -6 °C to -18 °C. When ice nucleation temperature is fixed at -10 °C, the mean pore size decreases from 250 to 150 μm, as the crosslinking degree increases from p = 3 to p = 7. Scaffold infiltration ability was quantified with synthetic microspheres. The seeding efficiency was assessed with MC3T3-E1 individual cells and HepaRG™ spheroids. These data collapse into a single master curve that exhibits a sharp transition from 100 % to 0 %-efficiency as the entity diameter approaches the mean pore size in the dry state. Altogether, we can thus precisely tune the porosity of these 3D materials of interest for 3D cell culture and cGMP production for tissue engineering.
Topics: Freeze Drying; Hydrogels; Ice; Porosity; Tissue Engineering
PubMed: 35891598
DOI: 10.1016/j.bioadv.2022.212973 -
Journal of the Mechanical Behavior of... Jul 2017To obtain hydroxyapatite (HA) coatings with high crystallinity which have long-term stability in clinical applications, coarse powders were usually injected to less...
To obtain hydroxyapatite (HA) coatings with high crystallinity which have long-term stability in clinical applications, coarse powders were usually injected to less energetic plasma. However, the HA coatings accumulated by partly melted particles usually have high porosity and poor mechanical properties, especially poor bonding strength. In this work, by profiting its quenching and mechanical impact, dry-ice blasting was in-situ employed during plasma spray process to improve the microstructure characterization and bonding strength of HA coatings. In addition, the influence of in-situ dry-ice blasting on the phase composition and crystallinity of plasma-sprayed HA coatings was investigated. The results show that a significant reduction of porosity and an apparent increase in bonding strength are revealed in plasma-sprayed HA coatings due to the cleaning effect of dry-ice blasting on the convex unmelted particles and splashing fragments. HA coatings prepared by the combination process of plasma spraying and dry-ice blasting have a compromise structure with minimum globular pores but with pronounced microcracks. The disappearance of CaO phase and the increase in crystallinity also derive from the application of dry-ice blasting.
Topics: Coated Materials, Biocompatible; Dry Ice; Durapatite; Materials Testing; Surface Properties
PubMed: 28292707
DOI: 10.1016/j.jmbbm.2017.03.003