BACKGROUND Cryopreservation of ovarian tissue can be used to preserve the fertility of patients who are about to receive treatment(s) that could compromise their future ovarian function. Here we evaluate the effectiveness of a vitrification protocol by carrying out a systematic comparison with a conventional slow-freezing method on human ovarian tissue. METHODS Human ovarian samples (mean age...

Ten methods to preserve phytoplankton populations for flow cytometric analyses were tested. These methods were differentiated by the rate of freezing and thawing, and the use or non-use of cryoprotectants (DMSO and/or glycerol) and chemical fixation. After freezing, the samples were stored in liquid nitrogen. These methods were tested on 3 freshwater and marine algal species. Different intensit...

Backgroud: Oocyte cryopreservation is critical in assisted reproduction techniques. However, the effect of cryopreservation on the oocyte has not been widely explored yet. Currently a thorough understanding of oocyte cryobiology is urgently required due to its far lag behind the forces propelling the clinical application of oocyte cryopreservation. Methods: In this study, we used two different ...

BACKGROUND Successful cryopreservation of oocytes and embryos is essential not only to maximize the safety and efficacy of ovarian stimulation cycles in an IVF treatment, but also to enable fertility preservation. Two cryopreservation methods are routinely used: slow-freezing or vitrification. Slow-freezing allows for freezing to occur at a sufficiently slow rate to permit adequate cellular deh...

We study opinion formation in a population of leftists, centrists and rightist. In an interaction between neighbouring agents, a centrist and a leftist can become both centrists or leftists (and similarly for a centrist and a rightist), while leftists and rightists do not affect each other. The evolution is controlled by the initial density of centrists ρ0. For any spatial dimension the system ...

BACKGROUND Ovarian tissue cryopreservation is the only option for preserving fertility in prepubertal girls and cancer patients requiring immediate treatment. Following ovarian tissue cryopreservation, fertility can be restored after tissue transplant or in vitro follicle maturation. METHODS Macaque (n= 4) ovarian cortex was cryopreserved using slow-rate freezing (slow freezing) or vitrificat...

The purpose of this study was to determine the negative effects (cryodamage) on human spermatozoa after freeze-thawing and to determine whether freeze-thawing of spermatozoa with a programmed slow freezer is better than freezing with liquid nitrogen vapour (rapid freezing) with regard to alterations in sperm chromatin and morphology in semen from fertile (donor) and subfertile, IVF/ICSI, patien...

STUDY QUESTION Does directional freezing improve the structural and functional integrity of ovarian fragments compared with conventional slow freezing and to whole ovary cryopreservation? SUMMARY ANSWER Compared with slow freezing, the use of directional freezing significantly improves all structural and functional parameters of ovarian fragments assessed in vitro and, overall, whole ovaries ...