Navegando por Palavras-chave "cryopreservation"
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- ItemSomente MetadadadosEffect of cryopreservation on sperm apoptotic deoxyribonucleic acid fragmentation in patients with oligozoospermia(Elsevier B.V., 2006-09-01) Paula, Thais Serzedello de [UNIFESP]; Bertolla, Ricardo Pimenta [UNIFESP]; Spaine, Deborah Montagnini [UNIFESP]; Cunha, Maria Adelaide [UNIFESP]; Schor, Nestor [UNIFESP]; Cedenho, Agnaldo Pereira [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Objective: To verify of the increase in sperm apoptotic DNA fragmentation during cryopreservation is greater in oligozoospermic patients than in normozoospermic controls.Design: Controlled prospective study.Setting: patients in an academic research environment.Patient(s): Forty-seven patients with oligozoospermia (concentration < 10 x 10(6) sperm/mL) and 30 normozoospermic men.Intervention(s): Sperm cryopreservation using a standard protocol with a test-yolk buffer, glycerol as the cryoprotectant.Main Outcome Measure(s): Rate of apoptotic sperm DNA fragmentation as assessed by the terminal deoxynucleotidyl-mediated deoxyuridine triphosphate nickend labeling (TUNEL) assay, graded in apoptotic or nonapoptotic, before and after cryopreservation.Result(s): An increase in apoptotic DNA fragmentation was observed in all the groups, regardless of sperm concentration. Normozoospermic men presented a smaller rate of apoptotic DNA fragmentation than oligozoospermic patients, both in pre- and postcryopreservation samples. the increase in DNA fragmentation was similar in both groups.Conclusion(s): Cryopreservation induces apoptotic sperm DNA fragmentation in men, regardless of sperm concentration. Men with oligozoospermia present with higher precryopreservation and postcryopreservation apoptotic sperm DNA fragmentation. the increase in DNA fragmentation is similar in both groups.
- ItemAcesso aberto (Open Access)Effects of the technique of cryopreservation and dilution/centrifugation after thawing on the motility and vitality of spermatozoa of oligoasthenozoospermic men(Sociedade Brasileira de Urologia, 2003-04-01) Esteves, Sandro C. [UNIFESP]; Spaine, Deborah M. [UNIFESP]; Cedenho, Agnaldo Pereira [UNIFESP]; Srougi, Miguel [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)OBJECTIVE: Comparing in human semen samples with low initial quality, the effects of 2 techniques of cryopreservation and dilution/centrifugation after thawing on the spermatic motility and vitality. MATERIALS AND METHODS: Semen samples from 15 oligo and/or asthenozoospermic individuals assisted in the infertility sector of a tertiary hospital were obtained through masturbation. The samples were divided into 2 portions of equal volume, and diluted (1:1; v/v) with the cryoprotector containing glycerol (Test yolk buffer). One portion was frozen through the technique of liquid nitrogen vapor with static phases (group I - GI), while the other was frozen through a programmable biological freezer with linear speed (Planer, Kryo 10, series III) (group II - GII). The following parameters were assessed before freezing and after thawing: percentage of spermatozoa with progressive motility (Prog%) and percentage of live spermatozoa (Vit%). After defrosting, Prog% was assessed before and after removal of cryoprotector diluent, in different time intervals (zero, 3 h, and 24 h). The statistical analysis has been accomplished by using the non-parametric tests of Wilcoxon and Friedman. RESULTS: There was significant reduction of Prog% and Vit% from before freezing to after defrosting in both groups, I and II (p < 0.001). Values of Prog% and Vit% were not statistically different between groups, after thawing. It has been observed a significant reduction in Prog% among portions frozen with the automated technique after dilution and centrifugation for removal of cryoprotector (p = 0.006). After cryoprotector removal, Prog% has been kept unaltered, in both groups, during the first 3 hours of incubation, although being superior in group I (p = 0,04). There was a significant decrease in Prog% after 24 hours of incubation, in both groups (p < 0,01). CONCLUSION: For human semen samples with low initial quality, freezing through vapor technique or through the automated technique showed to be equivalent in regarding recovery of live spermatozoa with progressive motility. The effects of dilution and centrifugation to remove the cryoprotector had a negative impact only in samples frozen through the automated technique. In both techniques, progressive motility is kept constant during the first 3 hours after thawing and removal of the cryoprotector, but is drastically diminished by the end of an incubation period of 24 hours.
- ItemSomente MetadadadosIs sperm cryopreservation an option for fertility preservation in patients with spinal cord injury-induced anejaculation?(Elsevier B.V., 2010-07-01) Silva, Barbara Ferreira da [UNIFESP]; Borrelli, Milton [UNIFESP]; Fariello, Roberta Maria [UNIFESP]; Restelli, Adriana Ester [UNIFESP]; Del Giudice, Paula Toni [UNIFESP]; Spaine, Deborah Montagnini [UNIFESP]; Bertolla, Ricardo Pimenta [UNIFESP]; Cedenho, Agnaldo Pereira [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Objective: To evaluate the effects of cryopreservation on sperm mitochondrial activity and nuclear DNA integrity in men with spinal cord injury.Design: Prospective controlled study.Setting: Patients in an academic research environment.Patient(s): Men with and without spinal cord injury-induced anejaculation.Intervention(s): Electroejaculation or penile vibrating stimulation semen cryopreservation using a commercial TEST-yolk-buffer technique.Main Outcome Measure(s): Rate of sperm DNA fragmentation as assessed by the comet assay, graded in Classes I (high DNA integrity) to IV (high DNA fragmentation). Mitochondrial activity as assessed by a method in which active mitochondria precipitate 3,3'-diaminobenzidine. Cells were classified as I (all active) to IV (all inactive). Semen was cryopreserved in a Test-yolk buffer, and motility, DNA fragmentation, and mitochondrial activity were analyzed precryopreservation and postthaw.Result(s): Before cryopreservation, when the study (SCI) and control groups were compared, no statistically significant differences were found with respect to concentration or total sperm count; however, the SCI group presented significantly lower ejaculate volume, decreased sperm morphology, and an increase in the round cell and neutrophils counts. in both groups, cryopreservation was associated with an increase in DNA fragmentation, a decrease in mitochondrial activity, and a decrease in motility, of which the latter was of greater importance in the control group.Conclusion(s): Cryopreservation causes a decrease in conventional seminal variables as well as in mitochondrial activity and DNA fragmentation. However, these were no more detrimental to sperm from men with SCI than to sperm from the control group. (Fertil Steril(R) 2010;94:564-73. (C) 2010 by American Society for Reproductive Medicine.)
- ItemSomente MetadadadosLight and Transmission Electronic Microscopy Evaluation of Lyophilized Corneas(Lippincott Williams & Wilkins, 2008-08-01) Farias, Roberta Jansen de Mello [UNIFESP]; Sousa, Luciene Barbosa de [UNIFESP]; Lima Filho, Acácio Alves de Souza [UNIFESP]; Lourenço, Andréia Cristina dos Santos [UNIFESP]; Tanakai, Marcia H.; Freymüller-Haapalainen, Edna [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Sorocaba Eye BankPurpose: Cornea storage for longer periods is still a challenge for corneal Surgeons. The purpose of this study was to find a method to lyophilize corneas for anterior lamellar transplant and to evaluate. them by light and transmission electronic microscopy.Methods: Corneal flaps were created by using a microkeratome. Corneas were lyophilized with a cryoprotectant (2.3 mol sacarousis for 40 minutes) and without a cryoprotectant in a lyophilization machine (Modulyon D). The corneas were rehydrated with distilled water, balanced saline solution (BSS), and phosphate-buffered saline, after which they were evaluated by microscopy. A cornea that did not undergo lyophilization served as a control.Results: Lyophilization without a cryoprotectant did not preserve the corneal structure. This finding was also observed when lyophilizing and rehydrating the corneas with distilled water or phosphate-buffered saline. We found that lyophilizing corneas and rehydrating them with 11 mL of BSS for 30 minutes preserved the general corneal structure, the parallelism of the collagen fibers, the Bowman layer, and the epithelial basement membrane for 15 and 30 days and for as long as 1 year or more.Conclusions: Lyophilization with sacarousis and rehydration with BSS may be a good method for anterior lamellar transplantation.
- ItemSomente MetadadadosRecovery of fertility after grafting of cryopreserved germinative tissue in female rabbits following radiotherapy(Oxford Univ Press, 2004-06-01) Almodin, Carlos Gilberto [UNIFESP]; Minguetti-Camara, V. C.; Meister, H.; Ferreira, JOHR; Franco, R. L.; Cavalcante, A. A.; Radaelli, MRM; Bahls, A. S.; Moron, Antonio Fernandes [UNIFESP]; |Murta, Carlos Geraldo Viana [UNIFESP]; Materbaby Reprod Humana & Genet; Universidade Estadual de Maringá (UEM); Universidade Federal de São Paulo (UNIFESP); Univ Fed Espirito SantoBACKGROUND: Many cancer survivors face infertility as a consequence of the aggressive treatment they must undergo. Cryopreservation of ovarian tissue before chemotherapy or radiotherapy may allow for tissue transplantation after the treatment, and restoration of fertility. We tested the potential of an orthotopic autografting of cryopreserved germinative tissue in female rabbits with ovarian failure following radiotherapy. METHODS: Ten adult multiparous female rabbits were randomly allocated into two groups, five in group I (control) and five in group II (transplant). All rabbits underwent right oophorectomy with cryopreservation of the germinative tissue, followed by sterilization of the remaining left ovary by radiotherapy. Later, group II rabbits received in the irradiated left ovary an implant of the frozen germinative tissue from the right ovary, whose small pieces were freely spread intracortically in a procedure we named 'intracortical sowing of germinative tissue' (ISGT). RESULTS: All group II rabbits conceived following spontaneous mating within 6 months of the transplant, whereas none of the remaining rabbits in group I had conceived up to 11 months after transplant. CONCLUSIONS: This study suggests that fertility can be restored in rabbits by sowing cortical tissue in a previously irradiated ovary. the clinical feasibility of this technique remains to be determined.