Possibility Of Cryopreservation Research Articles

Биоэтические аспекты применения репродуктивных технологий

The demographic situation in the modern world is problematic: the birth rate is declining, the rates of primary and secondary infertility are progressively increasing. Assisted reproductive technologies are methods to solve the problem of infertility. From the point of view of bioethics, there are a number of controversial issues: determining the personal status of the embryo, the ratio of risks and benefits for participants in the procedures, the possibility of cryopreservation, the destruction of “extra embryos”, etc. The purpose of our research was to study the attitude of the population to assessing the importance of bioethical aspects of the use of assisted reproductive technologies. During the study, an anonymous survey was conducted on the Google platform. The study involved 104 respondents of both sexes (83 women, 21 men) of various ages, mostly (59.6 %) in the category of 15–20 years. The survey questions were aimed at determining the degree of awareness of the participants about the problem of infertility and assisted reproductive technologies, the bioethical issues that they affect, as well as the subjective attitude to the use of these methods. Most of the respondents had an idea about the goals of assisted reproductive technologies and the bioethical problems that they generate. The survey participants noted the importance of communication between a doctor and a patient as one of the factors that makes it possible to increase the effectiveness of assisted reproductive technologies protocols: sympathy and moral support should be considered the basic norms of communication between a doctor and a patient with an infertility issue.

Cryopreservation in a Standard Freezer: -28 °C as Alternative Storage Temperature for Amniotic Membrane Transplantation.

Human amniotic membrane (hAM) is usually stored at −80 °C. However, in many regions, cryopreservation at −80 °C is not feasible, making hAM unavailable. Therefore, the possibility of cryopreservation at −28 °C (household freezer) was investigated. hAMs (n = 8) were stored at −80 °C or −28 °C for a mean time of 8.2 months. hAM thickness, epithelial integrity and basement membrane were assessed histologically. The collagen content, concentration of hepatocyte growth factor (HGF) and basic fibroblast growth factor (bFGF) were determined. Elastic modulus and tensile strength were measured. The mean thickness of hAM stored at −28 °C was 33.1 ± 21.6 µm (range 9.7–74.9); thickness at −80 °C was 30.8 ± 14.7 µm (range 13.1–50.7; p = 0.72). Mean collagen content, epithelial cell number and integrity score showed no significant difference between samples stored at −28 °C or −80 °C. Basement membrane proteins were well preserved in both groups. Mean tensile strength and elastic modulus were not significantly different. Concentration of bFGF at −28 °C was 1063.2 ± 680.3 pg/g (range 369.2–2534.2), and 1312.1 ± 778.2 pg/g (range 496.2–2442.7) at −80 °C (p = 0.11). HGF was 5322.0 ± 2729.3 pg/g (range 603.3–9149.8) at −28 °C, and 11338.5 ± 6121.8 pg/g (range 4143.5 to 19806.7) at −80 °C (p = 0.02). No microbiological contamination was detected in any sample. The cryopreservation of hAM at −28 °C has no overt disadvantages compared to −80 °C; the essential characteristics of hAM are preserved. This temperature could be used in an alternative storage method whenever storage at −80 °C is unavailable.

An integrated approach to conservation of rare fern species using the example of Polystichum craspedosorum (Dryopteridaceae) in Amur Region, Far East оf Russia

Currently changes in the earth's vegetative cover have reached a planetary scale. The danger of extinction of species and ecosystems has become increasingly significant. Active measures must be undertaken to restore particular plant species and populations in order to minimise an ongoing loss of species. Polystichum craspedosorum is a cliff-dwelling fern, an East-Asian relict species whose northern range includes the Russian Far East. The northernmost population of this species, located in the Amur Region, is at risk of flooding by the Lower Bureya Dam. A series of measures were developed and implemented to conserve this plant. Plant individuals were translocated from the flood zone to other suitable habitats on the territory of the Amur Region. Monitoring has indicated that, after three years, the translocated plants have their usual seasonal rhythm, sporulation and the formation of gemmae. The survival rate at new places ranged from 60% to 88%. However, the final conclusions about the research efficiency can be made only after long-term monitoring for more than ten years. Cultivation of this species is being done in outdoor conditions at the Amur Branch of the Far Eastern Botanical Garden-Institute of RAS. The seasonal rhythm of cultivated plants was similar to the natural one in both spore production and gemma formation. The species can be assigned to cold hardiness zone 3 and it is promising for cultivation in the Amur Region. The possibility of cryopreservation of P. craspedosorum spores has been studied along with in vitro culture. After ultra-low temperatures, spores did not lose their viability and, thus, they can be stored in cryobanks for a long time. An integrated approach provides the maximum opportunity for the species conservation in nature and in culture. This integrated approach to conservation of a rare fern species is unique for Russia.

Andrologie bei onkologischen Erkrankungen

In dermato-oncological treatment there are many gonadotoxic interventions. Alkylating and hormonally active substances as well as gonadal irradiation, in particular, are known to have afertilization-limiting effect in men. Since 2017 certified skin cancer centers in Germany therefore have the task to implement counselling on preservation of fertility. This is supported by the S2k guidelines on preservation of fertility in oncological treatment. Because recommendation of the various interventions from the dermato-oncological guidelines are dependent on the stage, the authors advocate at least the question "Is the desire to have children of interest to you?" when patients reach the appropriate stage. Fertility protection of men via cryopreservation of ejaculates or testicular tissue is then a simple and safe option. The procedure is standardized and usually available. In addition, the possibility of cryopreservation of testicular tissue from prepubertal male children and infants is now available via the new Androprotect project. If signs of hypogonadism occur during therapy, atreatment can be considered by weighing up the effects of testosterone but in this case it is important to take the anabolic and immunomodulating effects into account.

A robust, state-of-the-art amperometric microbiosensor for glutamate detection

Scientific knowledge of glutamate (GLU) neurobiology is severely hampered by the inadequacy of the available in vivo brain sampling techniques. Due to the crucial role of GLU in central nervous system function and pathology, the development of a reliable sampling device is mandatory. GLU biosensor holds potential to address many of the known issues of in vivo GLU measurement. We report here on the development and test of a labor- and cost-effective microbiosensor, suitable to be applied for measuring brain GLU. A glycerol-based cryopreservation method was also tested. Needle type Pt biosensors were coated with a permselective Nafion–Poly(o-phenylenediamine) layer and cross-linked to l-glutamate oxidase with poly(ethylene glycol) diglycidyl ether. Tested in vitro, the device shows high sensitivity and specificity for GLU, while being poorly influenced by common interfering substances such as ascorbate, dopamine and dihydroxyphenylacetic acid. Further, the cryopreservation procedure kept sensitivity unaltered for 30 days and possibly longer. We conclude that a highly efficient GLU biosensor of minimal dimensions can be consistently and affordably constructed with relative ease. Together with the possibility of cryopreservation this shall foster diffusion and exploitation of GLU biosensors technology.

Cryopreservation of veliger larvae of trumpet shell, Charonia sauliae: an essential preparation to artificial propagation

Trumpet shell, Charonia sauliae, is an endangered and valuable species, but its artificial propagation protocol has not been successfully established. To estimate the possibility of cryopreservation for larvae of C. sauliae, which is a potential preparation for its artificial reproduction and further research, in this study a protocol for the cryopreservation of veliger larvae of trumpet shell was optimized. Through a two-step cryopreservation procedure, four kinds of cryoprotectants (ethylene glycol, 1, 2-propanediol, dimethyl sulfoxide and glycerol) were employed at three concentrations (1.0, 1.5 and 2.0 molL−1) respectively and survival rates of larvae were determined after a storage of 1h. The larvae frozen with these four cryoprotectants after 1 h storage were cultured, and then survival rates were determined at 24, 72 and 120 h after thawing. Dimethyl sulfoxide at a concentration of 1.5 molL−1 showed the best protective effect in all experiments (p 0.05).

10.1007/s11827-008-1004-9

Structural and functional changes in cytoplasmic membranes and cell organelles play a crucial role in cell damage at low temperatures. These changes are reversible if adequate measures are taken to protect biological membranes against cold-induced injuries. In this study, the possibility of cryopreservation of membrane integrity by long-term storage of samples at low temperatures (−80°C) is demonstrated using differentiated nuclear blood cells as an example. In addition to classical methods, freezing of human leukocyte suspensions was carried out in a novel nontoxic cryoprotecting solution under a newly developed exponential freezing program based on the use of cryoprotectors and repair additives. This program ensures the same cryopreservation effect as the linear program, but is economically more efficient and less labor-consuming. After exponential freezing in a cryoprotecting solution and storage at −80°C, blood leukocytes retain their eosin resistance (91 ± 5% of thawed leukocytes) and phagocytic activity (76.7 ± 14.7% of thawed neutrophils) for 180 days. The novel technology of cell cryopreservation employing a nontoxic cryoprotecting solution, exponential freezing program, and fast thawing is economically efficient, easy to perform and applicable to storage of any animal cells.