A comparison between a new vitrification protocol and the slow freezing method in the cryopreservation of prepubertal testicular tissue.

Objective: This study aimed to compare a new vitrification protocol with reduced cryoprotectant exposure to the slow freezing method in the cryopreservation of prepubertal rat testicular tissue.

Methods: Five sexually immature male Wistar rats were submitted to bilateral orchiectomy. Tissue samples from each testicle were fragmented into small pieces and randomly assigned to three groups: Group A, fresh tissue (control); Group B, slow programmable freezing (SPF); and Group C (vitrification).

Viability of homologous and heterologous subcutaneous transplantation of fresh germ cells in rabbits.

Objective: This study aimed to compare heterologous to homologous transplantation of fresh ovarian germ cells in rabbits.

Methods: Twelve female white New Zealand rabbits (Oryctolagus cuniculus) were randomly numbered and submitted to bilateral oophorectomies. The ovaries from the six odd-numbered rabbits were dissected and cortical germinal tissue was digested in collagenase type 1 to obtain six solutions containing stromal and germ cells, which were injected in the abdominal region of the odd-numbered rabbits themselves (homologous transplantation) and of the even-numbered rabbits (heterologous transplantation) off immunosuppression.

The First Ovarian Tissue Transplant between Monozygotic Twin Sisters Discordant for Ovarian function in Latin America.

Ovarian tissue transplant is an alternative to the cryopreservation of oocytes and embryos for the recovery of fertility and natural hormonal activity. The objective of this paper is to report on the first fresh ovarian tissue transplant between monozygotic twin sisters discordant for ovarian function, using the subcortical implant technique of ovarian tissue fragments, to take place in Latin America. A strip representing approximately a quarter of the cortical tissue was removed from the right ovary of the donor sister, cleaned, cut into small fragments and sent to adjacent room, where the receptor sister was concomitantly being prepared to receive the tissue graft.

Vitrification of Human Oocytes and its Contribution to In Vitro Fertilization Programs.

Objeticve: To study the cumulative pregnancy outcome, particularly in terms of live births, with the consecutive transfer of embryos from fresh and vitrified/warmed oocytes to infertile patients in a routine infertility program.

Methods: Patients were initially submitted to in vitro fertilization embryo transfer with fresh embryos, while surplus oocytes were vitrified with the Vitri-Ingá method. Patients who did not succeed to carry their gestation to term underwent a new cycle with embryos from their own warmed oocytes.

A comparison of the effects of oral glutamine dipeptide, glutamine, and alanine on blood amino acid availability in rats submitted to insulin-induced hypoglycemia.

We compared the effects of oral administration of high-dose or low-dose glutamine dipeptide (GDP), alanine (ALA), glutamine (GLN), and ALA + GLN on the blood availability of amino acids in rats submitted to insulin-induced hypoglycemia (IIH). Insulin detemir (1 U/kg) was intraperitoneally injected to produce IIH; this was followed by oral administration of GDP, GLN + ALA, GLN, or ALA. We observed higher blood levels of GLN, 30 min after oral administration of high-dose GDP (1000 mg/kg) than after administration of ALA (381 mg/kg) + GLN (619 mg/kg), GLN (619 mg/kg), or ALA (381 mg/kg).

Short-term but not long-term hypoglycaemia enhances plasma levels and hepatic expression of HSP72 in insulin-treated rats: an effect associated with increased IL-6 levels but not with IL-10 or TNF-α.

The inducible expression of the 70-kDa heat shock proteins (HSP70) is associated with homeostatically stressful situations. Stresses involving sympathetic nervous system (SNS) activation, including α1-adrenergic agonists and physical exercise, are capable of inducing HSP70 expression and release of the HSP70 inducible form, HSP72. However, whether hypoglycaemia is capable of influencing HSP70 status under a stressful situation such as insulin-induced hypoglycaemia (IIH), which also involves SNS activation, is unsettled.

Evaluation of liver glycogen catabolism during hypercortisolism induced by the administration of dexamethasone in rats.

Background: The contribution of liver glycogen catabolism to hyperglycemia and glucose intolerance induced by pharmacological hypercortisolism were investigated.

Methods: For this purpose, adult male Wistar rats that received 1.0 mg/kg dexamethasone (DEX) ip at 8:00 a.

Embryo development and gestation using fresh and vitrified oocytes.

Background: The objective of this study was to compare the gestational results obtained with vitrified/thawed oocytes by a novel vitrification method (Vitri-ingá) to results obtained with fresh oocytes.

Methods: A total of 125 IVF-ET procedures carried out over 2008 were analysed, in which 79 patients received embryos from fresh oocytes (Group 1), and 46 patients received embryos from vitrified/thawed oocytes using Vitri-ingá (Group 2). Fresh and vitrified/thawed oocytes were fertilized and embryos were transferred.

A bovine protocol for training professionals in preimplantation genetic diagnosis using polymerase chain reaction.

Objective: To develop a bovine protocol for training in preimplantation genetic diagnosis (PGD) using PCR.

Design: Randomized study.

Setting: Human reproduction PCR laboratory.

Recovery of natural fertility after grafting of cryopreserved germinative tissue in ewes subjected to radiotherapy.

Objective: To recover natural fertility of ewes that were subjected to ovarian failure induced by radiotherapy with an autologous orthotopic graft of cryopreserved germinative tissue.

Design: Experimental surgery study.

Setting: University hospital unit.