Cryo letters最新文献

Background: In vitro maturation (IVM) and oocyte cryopreservation are therapeutic options in assisted reproductive technology which is used to preserve fertility in patients with different causes of infertility.

Objective: To analyze in vitro development of vitrified-warmed oocytes in the presence of human follicular fluid (FF) and bone marrow mesenchymal stem cell-conditioned medium (BMSC-CM) as a rescue strategy in fertility preservation.

Materials and methods: BMSC-CM and FF media were used as two natural media. Not only osteogenic and adipogenic differentiation but also flow cytometry was carried out to confirm the nature of mesenchymal stem cells. A total of 327 vitrified-warmed oocytes were randomly assigned to three groups with different maturation media. After 24 h the maturation rate was evaluated. In vitro fertilization and also embryo development were also assessed.

Results: Oocytes matured in the BMSC-CM and FF groups showed a significant increase compared to the control group (76.6+/-2.9, 53.2±1.0 , and 40.8+/-6.1, respectively) (P % 0.05). Embryo cleavage rates in the BMSC-CM were dramatically higher than FF and control groups (85.6+/-2.2, 70.5+/-2.2, and 60.7+/-1.5, respectively). Blastocyst formation rates in the BMSC-CM group were statically different compared to FF and control groups (73.6+/-1.0, 58.5+/-1.0, and 45.8+/-4.2, respectively).

Conclusion: BMSC-CM and FF media not only improve the maturation rate of vitrified warmed oocytes but also significantly increase embryo cleavage and blastocyst rates. DOI: 10.54680/fr23210110512.

Background: Due to the instability in oil/water emulsion, certain labile active ingredients were often not used in cosmetics.

Objective: The present study has tested the effect of freeze-drying to stabilize an oil/water cosmetic emulsion.

Materials and methods: A preliminary freeze-drying process was established at the basis of calorimetric and freeze-drying microscope studies. The stability of labile molecules in the cosmetic emulsion was evaluated at 48 degree C after freeze-drying.

Results: The accelerated stability experiment showed that the freeze-dried emulsion retained 90.1% vitamin C after 28 days at 48 degree C, whereas the oil-water emulsion retained only 28.3% vitamin C. The freeze-dried emulsion had significantly less oil oxidation than did the oil-water emulsion.

Conclusion: Freeze-drying improved the stability of vitamin C and oily active ingredients in cosmetic emulsions. DOI: 10.54680/fr23210110312.

Background: The cryopreservation of the sperm of the depik fish, Rasbora tawarensis, has previously been developed. However, the quality of the sperm post cryopreservation was not satisfactory and might be improved through the application of antioxidants.

Objective: To determine the most suitable antioxidant for the cryopreservation of the depik fish spermatozoa.

Materials and methods: A completely randomized design with a non-factorial experiment was used and the tested antioxidants were glutathione, beta-carotene, ascorbic acid, and butylated hydroxytoluene (BHT) at 6 % concentrations. All treatments had three replications. The sperms were collected from 10 male fishes and diluted with Ringer solution in a ratio of 1: 20 (v/v, sperm: Ringer solution). Then 5% DMSO and 5 % egg yolk were added to the diluted sperms. Furthermore, 6 % of the tested antioxidants were added to the diluents, and then, cryopreservation was carried out in liquid nitrogen for 14 days.

Results: The ANOVA test showed that the application of antioxidants significantly affected the sperm motility, fertility, and hatching rates of the eggs (P < 0.05). Furthermore, the antioxidants also protected the sperm cells during cryopreservation, with glutathione being the best antioxidant.

Conclusion: The application of antioxidants during the cryopreservation of depik fish sperm had a significant effect on motility, fertility and hatchability of eggs post-cryo. Furthermore, glutathione was the most suitable antioxidant. doi.org/10.54680/fr23110110312.

This review addresses a frequently encountered problem of designing an effective cryopreservation procedure for new (not previously cryopreserved) or difficult plant materials. This problem hinders worldwide efforts of applying cryopreservation across a wide genetic base of wild and a number of cultivated plants. We review recent advances in modifications of routinely applied cryoprotective solutions (CPAs) and suggest a practical approach to protocol development which embraces the physiological complexity of plant tissues as well as a wide spectrum of behaviours under CPA treatment. We suggest that vegetative plant materials are classified into four categories based on their size, structure, and the response to osmotic and chemical stresses provoked by CPA mixtures of varied composition and concentration, including alternative osmoprotection and vitrification solutions. A number of up to 15 preset protocols designed specifically for each category is then applied to the material. The protocols resulting in the best regrowth are then combined into the optimized procedure. The main advantage of this system over a conventional "trial-and-error" search for working cryopreservation protocol is a minimal amount of starting materials required for the tests and a relatively accurate prediction of material behaviour under cryopreservation stress provided by the relatively few CPAs treatments. The unifying principles revealed by this approach could broaden a spectrum of wild species and materials which can be safely conserved by cryopreservation. Also anticipated is application of this approach to plant materials of biotechnological value as well as cultivars of agricultural and horticultural crops which do not respond well to standard protocols developed for their kind. doi.org/10.54680/fr23110110112.

Background: Skin cryobanks represent important tools for the conservation of the maximum genetic representation of a population, especially those with a certain degree of threat to extinction, such as the ocelot. A relevant step towards the proper establishment of these banks is the definition of adequate cryopreservation techniques for the conservation of the skin.

Objective: We evaluated the effects of two different techniques [direct vitrification in cryovials (DVC) and solid-surface vitrification (SSV)] for the preservation of ear skin derived from ocelot.

Materials & methods: For both techniques, we vitrified the ear skin using Dulbeccos modified Eagles medium with 3.0 M dimethyl sulfoxide, 0.25 M sucrose, and 10% fetal bovine serum. Non-cryopreserved tissues were used as control (control group). All tissues were analyzed for their morphometric characteristics by conventional histology and morphological / functional analysis by cell ability during the culture.

Results: While tissues cryopreserved by DVC showed similar values for dermis thickness and number of perinuclear halos to the control, tissues cryopreserved by SSV showed similarities to the control regarding the number of melanocytes, percentage of collagen fibers, and numbers of viable cells by apoptosis analysis. Additionally, none of the vitrification techniques affected stratum corneum thickness, number of keratinocytes, tissue proliferative activity, cell viability, or metabolism.

Conclusion: Both vitrification techniques (DVC and SSV) can be used for the conservation of ocelot skin; however, SSV guarantees a higher cellular quality after in vitro tissue culture in most of the parameters evaluated, such as viability, metabolism, and apoptosis analysis. doi.org/10.54680/fr23110110412.