OBJECTIVE To evaluate the efficacy of a new ultravitrification technique with a low concentration of cryoprotectants. DESIGN Ultravitrification research. SETTING Private assisted reproduction center. PATIENT(S) Oocytes donated voluntarily with the aim of research. INTERVENTION(S) Ultravitrification with different protocols of 100 mature oocytes and 100 immature oocytes divided in four g...

We describe here a new cryobiological and neurobiological technique, aldehyde-stabilized cryopreservation (ASC), which demonstrates the relevance and utility of advanced cryopreservation science for the neurobiological research community. ASC is a new brain-banking technique designed to facilitate neuroanatomic research such as connectomics research, and has the unique ability to combine stable...

BACKGROUND To develop novel cryopreservation methods, we estimated the permeability coefficients Lp (hydraulic conductivity) and P(EG) (cryoprotectant permeability) of mature human oocytes after exposure to ethylene glycol (EG) and tested the efficiency of a multi-step slow cooling protocol based on this cryoprotectant. METHODS Oocytes were perfused with 1.5 mol/l EG for 10 min. Oocyte volume...

OBJECTIVE To develop an efficient technique to preserve primordial follicles from cryopreserved ovarian tissue. DESIGN Frozen-thawed and fresh preantral follicles were mechanically isolated for viability testing, and their morphology was histologically analyzed. SETTING Laboratory of Animal Reproduction, Faculty of Veterinary Medicine and Zootechny, University State of São Paulo, Brazil. ...

The beneficial human gut microbe Faecalibacterium prausnitzii is a 'probiotic of the future' since it produces high amounts of butyrate and anti-inflammatory compounds. However, this bacterium is highly oxygen-senstive, making it notoriously difficult to cultivate and preserve. This has so far precluded its clinical application in the treatment of patients with inflammatory bowel diseases. The ...

Our aim was to optimize a cryoprotectant treatment for vitrification of immature porcine cumulus-oocyte complexes (COCs). Immature COCs were vitrified either in 35% ethylene glycol (EG), 35% propylene glycol (PG) or a combination of 17.5% EG and 17.5% PG. After warming, the COCs were in vitro matured (IVM), and surviving oocytes were in vitro fertilized (IVF) and cultured. The mean survival rat...

AIM Oocyte cryopreservation remains largely experimental, with live birth rates of only 2-4% per thawed oocyte. In this study, we present a nanoliter droplet technology for oocyte vitrification. MATERIALS & METHODS An ejector-based droplet vitrification system was designed to continuously cryopreserve oocytes in nanoliter droplets. Oocyte survival rates, morphologies and parthenogenetic devel...