Search results for "Cryopreservation"
showing 8 items of 148 documents
Pancreatic islets from non-heart beating donor pig: Two-layer preservation method in an in vitro porcine model
2011
Purpose Pancreata from non-heart beating donors could represent an unlimited source of islets if their cell viability can be efficiently preserved during the time necessary to process the organs by the use of a better solution of preservation compared to the classic University of Wisconsin solution. The aim of this study was to determine whether it is possible to obtain functioning “alive islets” from non-heart-beating donors by comparing, on a porcine model, the classic “UW ice-store” method with a two-layer cold storage method (TLM) using oxygenated Perfluorocarbons (PFC) and UW. Methods Whole pancreata were harvested from 20 NHBDs female pigs with similar characteristics and preserved fo…
Vitrification of zona-free rabbit expanded or hatching blastocysts: a possible model for human blastocysts.
2003
BACKGROUND: The purpose of this study was to test the effectiveness of one two-step (A) and two one-step (B1 and B2) vitrification procedures on denuded expanded or hatching rabbit blastocysts held in standard sealed plastic straws as a possible model for human blastocysts. The effect of blastocyst size was also studied on the basis of three size categories (I: diameter <200 μm; II: diameter 200-299 μm; III: diameter ≥300 μm). METHODS: Rabbit expanded or hatching blastocysts were vitrified at day 4 or 5. Before vitrification, the zona pellucida was removed using acidic phosphate buffered saline. For the two-step procedure, prior to vitrification, blastocysts were pre-equilibrated in a solut…
Viability and function of the cryopreserved whole rat ovary: comparison between slow-freezing and vitrification
2011
Objective To investigate four different protocols for cryopreservation of the whole rat ovary with intact vasculature to evaluate whether differences exist in post-thawing viability of the ovary after either vitrification or slow freezing. Design Experimental study. Setting Obstetrics and gynecology department. Animal(s) Immature Sprague-Dawley female rats. Intervention(s) Ovaries were isolated with the vascular tree intact up to the bifurcation of the abdominal aorta and were subsequently cannulated. The ovaries were flushed with increasing concentrations of the cryoprotectant dimethyl sulfoxide (DMSO) to either 1.5 or 7 M. The ovaries underwent cryopreservation by vitrification or passive…
Predictors of live birth in women with a history of biochemical pregnancies after assisted reproduction treatment
2020
Abstract Objectives To ascertain whether women with a history of biochemical pregnancies (BPs) in in-vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) treatment cycles have decreased chances of live birth (LB); and (2) to build a predictive model for LB in this particular population of infertile women. Methods In order to achieve the first objective, data from 1536 women that had a LB using autologous fresh or frozen embryos, or dropped out of further IVF/ICSI treatments after completing one to three unsuccessful treatment cycles were retrospectively analyzed. A subpopulation of 90 women that experienced one or more BPs in our assisted reproduction unit were selected to buil…
Additive effect of factors related to assisted conception on the reduction of maternal serum pregnancy-associated plasma protein A concentrations and…
2013
Objective To analyze whether assisted conceptions need adjustments in first-trimester Down syndrome screening and why modifications in screening markers occur. Design Eleven-year cohort retrospective analysis. Setting Maternal-fetal medicine unit. Patient(s) Two thousand eleven naturally conceived normal singleton pregnancies and 2,042 normal singleton pregnancies achieved with assisted conception: 350 by IUI and 1,692 with IVF (n = 328) or intracytoplasmic sperm injection (ICSI; n=1,364), using nondonor (n = 1,086) or donated ova (n = 606), with fresh (n = 1,432) or frozen (n = 260) embryos. Intervention(s) Comparison of ultrasound and biochemical markers of first-trimester Down syndrome s…
Modified cryopreservation and xenotransplantation of human parathyroid tissue.
1999
Introduction: A modified cryopreservation technique for human parathyroid tissue was compared with the standard method using a programmed freezer. Methods: Total parathyroidectomy was performed in three groups of 6-week-old Rowett nude rats. Group I (control) underwent no transplantation of parathyroid tissue (n=9). After 10 days, the rats of groups II (n=15) and III (n=15) underwent xenotransplantation of 20 mg cryopreserved human parathyroid tissue, which had been stored in liquid nitrogen at –196°C for 1–22 months prior to xenotransplantation. The parathyroid tissue was derived from 15 parathyroidectomized patients with renal hyperparathyroidism. Two tissue samples were obtained from eve…
Cryopreservation of Hazelnut (Corylus avellana L.) Axillary Buds from In Vitro Shoots Using the Droplet Vitrification Method
2021
Cryopreservation by droplet vitrification was applied to hazelnut (Corylus avellana L.). axillary buds of the Italian cultivated variety Tonda Gentile Romana, which were collected from in vitro growing shoots, immersed in ice cooled PVS2 or PVS3 for 60 or 90 min, then transferred to a droplet of vitrification solution, placed on a strip of aluminium foil, and plunged into liquid nitrogen (LN). Additionally, the effect on the recovery of the mother plant after cryopreservation was evaluated, following a cold pre-treatment at 4 °C for 3 months. The highest regrowth percentage (56.7%) was obtained after applying PVS3 for 60 min, while the application of PVS2 for the same amount of time reduced…
Flagship species of the Pieniny NP. protected ex situ at PAS BGCBDC seed bank at WARSAW-POWSIN
2014
Pieniny Mts. are important biodiversity hotspot in Central Europe. According to Pieniny National Park Long Term Conservation Plan 2000-2020 small, isolated populations of some of Pieniny NP flagship species can become extinct till 2020. That is why their ex situ preservation at seed bank is justified and reasonable as supplement of active and passive in situ conservation measures carried out by National Park staff. PAS Botanical Garden – Center for Biological Diversity Conservation at Warsaw-Powsin has a long tradition of cooperation with Pieniny National Park (S Poland). This article focuses on the actions undertaken during EU funded conservation project: “Ex situ conservation of native, t…