Cryobiology

Artificial insemination with cryopreserved semen is a well-developed technique commonly used for controlled reproduction in cattle. However, despite current technical advances, cryopreservation continues to damage bull spermatozoa, resulting in a loss of approximately 30 to 50% of viable spermatozoa post thawing. To further improve the efficiency of cryopreservation of bull spermatozoa, understanding the molecular mechanisms underlying the cryobiological properties that affect cryoinjuries during cryopreservation process of bull spermatozoa is required...

PURPOSE:  Local ablative therapies have become an established treatment option in interventional oncology. Radiofrequency ablation (RFA) and microwave ablation (MWA) are a standard of care in the treatment of hepatocellular carcinoma (HCC). Currently, there is an increasing interest in cryotherapy, one of the oldest ablation techniques. It has some unique characteristics with regard to technology and mechanism of action. MATERIALS AND METHODS:  A systematic literature search using the terms cryotherapy, cryosurgery and cryoablation was performed...

Ice formation, mainly consisting of ice nucleation, ice growth, and ice recrystallization, is ubiquitous and crucial in wide-ranging fields from cryobiology to atmospheric physics. Despite active research for more than a century, the mechanism of ice formation is still far from satisfactory. Meanwhile, nature has unique ways of controlling ice formation and can provide resourceful avenues to unravel the mechanism of ice formation. For instance, antifreeze proteins (AFPs) protect living organisms from freezing damage via controlling ice formation, for example, tuning ice nucleation, shaping ice crystals, and inhibiting ice growth and recrystallization...

Confucius said study the past if you would define the future and a popular statement says that history depends on who writes it. To talk about history it is necessary to find and define a milestone where to start the narration. The intention of this quick review is to take the reader through moments and selected publications; part and pieces of memories showing how the concept of cryopreservation, specifically for mouse sperm, was conceived and sustained as we know it today. Beginning with the development of the microscope (1677) and continuing through the 17th century with the first documented observation by L...

Freeze-thaw stress causes various types of cellular damage, survival and/or proliferation defects, and metabolic alterations. However, the mechanisms underlying how cells cope with freeze-thaw stress are poorly understood. Here, model dough fermentations using two baker's yeast strains, 45 and YF, of Saccharomyces cerevisiae were compared after 2 weeks of cell preservation in a refrigerator or freezer. YF exhibited slow fermentation after exposure to freeze-thaw stress due to low cell viability. A DNA microarray analysis of the YF cells during fermentation revealed that the genes involved in oxidative phosphorylation were relatively strongly expressed, suggesting a decrease in the glycolytic capacity...

To model the cryobiological responses of cells and tissues, the cellular membrane permeability characteristics are often measured at suprazero temperatures as well as at subzero temperatures with and without the presence of extra-cellular ice. These measured membrane permeability characteristics are then used to predict the responses of cells and tissues for a given thermal insult with the ultimate aim of mitigating the damage caused during the freeze-thaw process. This brief review articles summarizes efforts from my research group over the past 15 years as related to cryobiology of mammalian ovarian tissue sections, i...

Between 1970 and 2012, vertebrate abundance has declined by 58% with an average annual decline of 2%, calling for serious action to prevent a mass extinction and an irreversible loss of biodiversity. Cryobanks and cryopreservation have the potential to assist and improve ex situ and in situ conservation strategies by storing valuable genetic material. A great deal of studies concerning cryopreservation have been performed within the class Mammalia, although no systematic overview has previously been presented...

Cryopreservation provides valuable genes for further breeding of elite cultivars, and cryotherapy improves the production of virus-free plants in Malus spp., thus assisting the sustainable development of the apple industry. Apple (Malus spp.) is one of the most economically important temperate fruit crops. Wild Malus genetic resources and existing cultivars provide valuable genes for breeding new elite cultivars and rootstocks through traditional and biotechnological breeding programs. These valuable genes include those resistant to abiotic factors such as drought and salinity, and to biotic factors such as fungi, bacteria and aphids...

Spermatozoa undergo apoptotic changes during the cryopreservation process. These changes, recently termed spermptosis, resemble the cryopreservation induced delayed onset of cell death observed after thawing of somatic cells. Due to its importance in cryobiology, methods to easily identify spermptotic cells are warranted. In this study, a well-validated method for identification of spermatozoa with caspase 3 activity was compared with use of the combination of Hoechst 33342 (H-42) and ethidium homodimer (Eth-1)...

No abstract text is available yet for this article.

The prediction of nonideal chemical potentials in aqueous solutions is important in fields such as cryobiology, where models of water and solute transport-that is, osmotic transport-are used to help develop cryopreservation protocols and where solutions contain many varied solutes and are generally highly concentrated and thus thermodynamically nonideal. In this work, we further the development of a nonideal multisolute solution theory that has found application across a broad range of aqueous systems. This theory is based on the osmotic virial equation and does not depend on multisolute data...

Aquaporins (AQPs) play a vital role for the transport of water and solutes across cell membranes. Classification of these ubiquitous proteins into three categories (orthodox AQPs, aquaglyceroporins and superaquaporins) is based on their sequence similarity and substrate selectivity. In the male reproductive tract of mammals, most AQPs (except AQP6 and AQP12) are found in different organs (including testis, efferent ducts and epididymis). AQP1 and AQP9 are the most abundant AQPs in the efferent ducts and epididymis and play a crucial role for the secretion/reabsorption dynamics of luminal fluid during sperm transport and maturation...

Thermodynamic phase behavior is affected by curved interfaces in micro- and nanoscale systems. For example, capillary freezing point depression is associated with the pressure difference between the solid and liquid phases caused by interface curvature. In this study, the thermal, mechanical, and chemical equilibrium conditions are derived for binary solid-liquid equilibrium with a curved solid-liquid interface due to confinement in a capillary. This derivation shows the equivalence of the most general forms of the Gibbs-Thomson and Ostwald-Freundlich equations...

No abstract text is available yet for this article.

An ability to store cells (if they cannot be used fresh) reduces cell wastage, thereby increasing the supply of transplantable material. Cell storage is also valuable in scientific research, allowing material to be archived and experiments to be repeated from the same tissue source and facilitating research collaboration by allowing stored samples to be distributed. Cryopreservation is currently considered the most promising and successful, long-term biological conservation method. Its use has led to optimizing survival, improving protocols and stem cell and neuroglia viability, thereby assuring its future use in neuroregeneration and restoration regarding cell therapy...

In tissue engineering, decellularized scaffolds have been proved to have remarkable capacity to promote regeneration in various organs such as kidney, heart, lung, and liver. Marrying the field of cryobiology and reproductive medicine resulted in considerable progress and breakthroughs, which led to the emergence of ovarian tissue cryopreservation and transplantation as a promising option for fertility preservation. Here we describe an innovative application of decellularized tissue scaffolds as a regenerative platform for reconstruction of ovarian grafts for auto-transplantation...

Cryopreservation has become a central technology in many areas of clinical medicine, biotechnology, and species conservation within both plant and animal biology. Cryoprotective agents (CPAs) invariably play key roles in allowing cells to be processed for storage at deep cryogenic temperatures and to be recovered with high levels of appropriate functionality. As such, these CPA solutes possess a wide range of metabolic and biophysical effects that are both necessary for their modes of action, and potentially complicating for cell biological function...

This chapter will describe the use of the Irvine Scientific(®) vitrification and warming solutions (Vit Kits(®)) along with a detailed protocol for the correct use of the CryoTip(®) vitrification device for human embryos and oocytes. Successful pregnancies have been reported after carrying out rapid vitrification methods of oocytes, cleavage stage embryos, and blastocysts using the CryoTip(®) (Popwell et al. Fertil Steril, 101:e20, 2014; Kuwayama et al. Reprod Biomed 11:608-614, 2005; Kuwayama et al. Fertil Steril 84:S187, 2005; Kuwayama et al...

Due to their high biological complexity, e.g., their close cell-to-cell contacts, cryopreservation of human pluripotent stem cells with standard slow-rate protocols often is inefficient and can hardly be standardized. Vitrification that means ultrafast freezing already showed very good viability and recovery rates for this sensitive cell system, but is only applicable for low cell numbers, bears a high risk of contamination, and can hardly be implemented under GxP regulations. In this chapter, a sterile plate-based vitrification method for adherent pluripotent stem cells and their derivatives is presented based on a procedure and device for human embryonic stem cells developed by Beier et al...

The control of ice nucleation is of fundamental significance in many process technologies related to food and pharmaceutical science and cryobiology. Mechanical perturbation, electromagnetic fields and ice-nucleating agents (INAs) have been known to induce ice nucleation in a controlled manner. But these ice-nucleating methods may suffer from cumbersome manual operations, safety concerns of external fields, and biocompatibility and recovery issues of INA particles, especially when used in living systems. Given the automatic ice-seeding nature of INAs, a promising solution to overcome some of the above limitations is to engineer a biocomposite that accommodates the INA particles but minimizes their interactions with biologics, as well as enabling the recovery of used particles...