231 resultados para Sperm preservation


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Testicular sperm extraction (TESE) associated with intracytoplasmic sperm injection has allowed many men presenting non-obstructive azoospermia to achieve fatherhood. Microdissection TESE (microTESE) was proposed as a method to improve sperm retrieval rates in these patients; however, there have been failures. Little is known about whether microTESE leads to spermatogenic alterations in the contralateral testis. We assessed histological outcomes of experimental microTESE in the contralateral testis of adult male rabbits. Nine adult male rabbits were divided into three groups: control (testicular biopsy to observe normal histological and morphometric values), sham (incision of the tunica vaginalis, and a contralateral testicular biopsy to observe histological and morphometric patterns, 45 days later), and study (left testicular microTESE, and a right testicular biopsy to observe histological and morphometric patterns, 45 days later). Sections were assessed by calculating Johnsen-like scores, and measuring total tubule diameter, lumen diameter and epithelial height. The results were compared using ANOVA and Bonferroni's statistical analysis. Morphometric evaluation of the seminiferous tubules did not demonstrate differences between the three groups. However, microTESE caused spermatogenic alterations, leading to maturation arrest in the contralateral testis.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The routine semen evaluation assessing sperm concentration, motility and morphology, does not identify subtle defects in sperm chromatin architecture. Bulls appear to have stable chromatin, with low levels of DNA fragmentation. However, the nature of fragmentation and its impact on fertility remain unclear and there are no detailed reports characterizing the DNA organization and damage in this species. The intensive genetic selection, the use of artificial insemination and in vitro embryo production associated to the cryopreservation process can contribute to the chromatin damage and highlights the importance of sperm DNA integrity for the success of these technologies. Frozen-thawed semen samples from three ejaculates from a Nellore bull showed high levels of morphological sperm abnormalities (55.8±5.1%), and were selected for complementary tests. Damage of acrosomal (76.9±8.9%) and plasma membranes (75.7±9.3%) as well as sperm DNA strand breaks (13.8±9.5%) and protamination deficiency (3.7±0.6%) were significantly higher compared to the values measured in the semen of five Nellore bulls with normospermia (24.3±3.3%; 24.5±6.1%; 0.6±0.5%; 0.4±0.6% for acrosome, plasma membrane, DNA breaks and protamine deficiency, respectively) (P<0.05). Motility and percentage of spermatozoa with low mitochondrial potential showed no differences between groups. This study shows how routine semen analyses (in this case morphology) may point to the length and complexity of sperm cell damage emphasizing the importance of sperm function testing.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Pós-graduação em Medicina Veterinária - FCAV

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

OBJECTIVE: To assess the presence of microorganism contamination in the preservation solution for transplant organs (kidney/pancreas). Method: Between August 2007 and March 2008, 136 samples of preservation solution were studied prior to graft implantation. Variables related to the donor and to the presence of microorganisms in the preservation solution of organs were evaluated, after which the contamination was evaluated in relation to the recipient culture variable. Univariate and multivariate statistical analyses were performed. RESULTS: The contamination rate of the preservation solution was 27.9%. Coagulase-negative Staphylococcus was the most frequently isolated microorganism. However, highly virulent agents, such as fungi and enterobacteria, were also isolated. In univariate analysis, the variable donor antibiotic use was significantly associated to the contamination of the preservation solution. on the other hand, multivariate analysis found statistical significance in donor antibiotic use and donor's infectious complications variables. CONCLUSIONS: In this study, 27.9% of the preservation solutions of transplant organs were contaminated. Infectious diseases and non-use of antibiotics by the donor were significantly related to the presence of microorganisms in organ preservation solutions. Contamination in organ preservation solutions was not associated with infection in the recipient.