Impact of adrenalectomy and dexamethasone treatment on testicular morphology and sperm parameters in rats: insights into the adrenal control of male reproduction

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

IS CLEISTOSPERMY AND COENOSPERMY RELATED TO SPERM TRANSFER? A COMPARATIVE STUDY OF THE MALE REPRODUCTIVE SYSTEM OF PACHYGRAPSUS TRANSVERSUS AND PACHYGRAPSUS GRACILIS (BRACHYURA: GRAPSIDAE)

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

Microdissection testicular sperm extraction causes spermatogenic alterations in the contralateral testis

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.

Reintroducing the red-billed curassow in Brazil: Population viability analysis points to potential success

Reintroduction can be enhanced by data from long-term post-release monitoring, which allows for modeling opportunities such as population viability analysis (PVA). PVA-relevant data were gathered via long-term monitoring of reintroduced red-billed curassows at the Guapiacu Ecological Reserve (REGUA), located in Rio de Janeiro, Brazil, over 25 months. In the present article, we (1) assess the robustness of the reintroduction plan, (2) evaluate the viability of the current reintroduced population, and (3) examine mitigation options to increase the viability of this population. VORTEX indicates that the initial plan, fully implemented, was likely to establish a viable population at REGUA. The current population is unviable; the best mitigation strategies are to eliminate hunting altogether, or at least reduce it by half, and to supplement ten immature pairs in 2015. A positive long-term outcome at REGUA is still possible; we encourage the Brazilian government and private stakeholders to consider population supplementation, both to achieve success at REGUA and to improve the evidence base for future reintroductions. (C) 2014 Associacao Brasileira de Ciencia Ecologica e Conservacao. Published by Elsevier Editora Ltda.

Effect of hydrogen peroxide on thawed ovine sperm motility

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

Preservation of wild feline semen by freeze-drying: experimental model

According to the Convention on International Trade in Endangered Species, 36 wild feline species are threatened by extinction or severely endangered, and to save them is the target of several conservation programs. This study aimed to assess the viability of the freeze-drying technique for domestic cat sperm cells, with the ultimate goal of transferring this technology to the wild feline species. The domestic cat is an excellent experimental model for wild felids. It is in this scenario that the freeze-drying process (low-temperature vacuum dehydration) of sperm cells shows its value in preserving male cats' germplasm. Results from membrane and DNA integrity analysis are promising and validates the use of frozen-dried sperm samples in intracytoplasmic sperm injections (ICSIs). Further studies are still necessary to evaluate the ICSI embryo production using domestic cat frozen-dried sperm and the possibility of using such technology with wild felines.

Principais marcadores utilizados na avaliação da qualidade do sêmen de animais domésticos

Methods of semen cryopreservation allow changes in spermatic cells, such as damage in plasma and acrossomal membrane and modifications in mitochondrial function due to a disorder in the lipidic bilayer. For effective oocyte fertilization, spermatozoa require functional competent membranes, and intact organelles, acrosome and DNA. However, most laboratory methods used to evaluate semen quality are not highly correlated with fertilizing capacity. The discovery of a variety of fluorochromes and compounds conjugated to fluorescent probes has enabled an accurate assessment of the viability, integrity and function of spermatozoa. Among the most used probes that label the various compartments of the sperm cell there are the membrane impermeable fluorescent dyes to test the membrane integrity, as well as acylated dyes that pass the intact membrane. For the acrossomal integrity the most commonly used method is lectins labeled by a fluorescent probe. The acrosome reaction and spermatic capacitation is detected by the evaluation of membrane architecture and disorder of lipids in plasma membrane. Mitochondrial function can be determined using markers for their aerobic activity. The DNA status of spermatozoa has been determined using the metachromatic properties of Acridine Orange, and the DNA fragmentation can also be assessed by TUNEL assay. Finally, DNA condensation is analyzed using a single cell DNA gel electrophoresis assay that indicates DNA compactation. This monograph aims to compile the various tests used to detect damaged spermatozoa under cryopreservation methods, searching for improve the predictive value of semen analysis with the intention of a successful conception

Congelação de células espermáticas provenientes de epidídimo de gatos domésticos contendo antioxidante no meio diluidor

Pós-graduação em Medicina Veterinária - FCAV

Viability of Lactobacillus acidophilus La-5 in the presence of Williopsis saturnus var. suaveolens

Maintaining the viability of probiotic microorganisms from production to consumption has long been a technological challenge for the food industry. The objectives of this study were to evaluate the in vitro interaction between Lactobacillus acidophilus La-5 and Williopsis saturnus var. suaveolens and the effect of this yeast on acidification kinetics, viability of Lactobacillus acidophilus and post-acidification in fermented milk during refrigerated storage at 5 °C. The in vitro study showed a positive interaction between the acid cell free-supernatant (CFS) of probiotic bacteria La-5 and the yeast. The addition of W. saturnus var. suaveolens increased the fermentation time due to consumption of the organic acids produced by L. acidophilus. During the refrigerated storage of the samples, the presence of the yeast increased the viability of L. acidophilus and reduced post-acidification. However, the mechanism of such interaction of bacteria and yeast is not fully understood.

Immediate and late analysis of dental pulp stem cells viability after indirect exposition to alternative in-office bleaching strategies

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

Effect of LPS treatment on the viability and chemokine synthesis by epithelial cells and gingival fibroblasts

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

Impaired protamination and sperm DNA damage in a Nellore bull with high percentages of morphological sperm defects in comparison to normospermic bulls

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.