Search results for "sperma"

PSCDGs of mouse multipotent adult germline stem cells can enter and progress through meiosis to form haploid male germ cells in vitro

2010

Spermatogonial stem cells (SSCs) provide the basis for spermatogenesis throughout adult life by undergoing self-renewal and differentiation into sperm. SSC-derived cell lines called multipotent adult germline stem cells (maGSCs) were recently shown to be pluripotent and to have the same potential as embryonic stem cells (ESCs). In a differentiation protocol using retinoic acid (RA) and based on a double selection strategy, we have shown that ESCs are able to undergo meiosis and produce haploid male germ cells in vitro. Using this differentiation protocol we have now succeeded to generate haploid male germ cells from maGSCs in vitro. maGSCs derived from a Stra8-EGFP transgenic mouse line wer…

CEP63 deficiency promotes p53-dependent microcephaly and reveals a role for the centrosome in meiotic recombination

2015

Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAM

Acrosin, the peculiar sperm-specific serine protease.

1991

The sperm enzyme acrosin has long been known as one of the key enzymes in the mammalian fertilization process. Elucidation of primary structures of preproacrosin from various species have allowed a deeper insight into the structural organization and the complex evolution of the sperm proteinase acrosin. In addition to the typical elements of serine proteases, the acrosin molecule possesses one novel domain that might convey DNA-binding properties.

Afterword to

2016

Morphometric comparison by the ISAS

2016

DNA fragmentation has been shown to be one of the causes of male infertility, particularly related to repeated abortions, and different methods have been developed to analyze it. In the present study, two commercial kits based on the SCD technique (Halosperm® and SDFA) were evaluated by the use of the DNA fragmentation module of the ISAS® v1 CASA system. Seven semen samples from volunteers were analyzed. To compare the results between techniques, the Kruskal–Wallis test was used. Data were used for calculation of Principal Components (two PCs were obtained), and subsequent subpopulations were identified using the Halo, Halo/Core Ratio, and PC data. Results from both kits were significantly …

Computer-assisted sperm morphometry fluorescence-based analysis has potential to determine progeny sex

2016

This study was designed to determine the ability of computer-assisted sperm morphometry analysis (CASA-Morph) with fluorescence to discriminate between spermatozoa carrying different sex chromosomes from the nuclear morphometrics generated and different statistical procedures in the bovine species. The study was divided into two experiments. The first was to study the morphometric differences between X- and Y-chromosome-bearing spermatozoa (SX and SY, respectively). Spermatozoa from eight bulls were processed to assess simultaneously the sex chromosome by FISH and sperm morphometry by fluorescence-based CASA-Morph. SX cells were larger than SY cells on average (P < 0.001) although with impo…

Repetitive DNAs in the slug Milax nigricans: association of ribosomal (18S–28S and 5S rDNA) and (TTAGGG)n telomeric sequences) in the slug M. nigrica…

2003

Spermatocyte chromosomes of the slug Milax nigricans (Mollusca: Gastropoda: Pulmonata) were studied using silver staining (Ag-NOR) and fluorescent in situ hybridization (FISH) with four repetitive DNA probes [18S rDNA, 5S rDNA, (TTAGGG)n and (GATA)n]. Silver impregnation was inadequate to localize the chromosome sites of nucleolus organizer regions (NORs) since no silver dots occurred on the chromosomes at spermatogonial metaphase and a diffuse silver stainability could be observed on the bivalents at metaphase-I. Unlike silver staining, single-colour rDNA FISH consistently mapped major ribosomal sites (18S-28S rDNA) on two small-sized chromosomes in spermatogonial cells and on the correspo…

Kinematics and subpopulations' structure definition of blue fox (Alopex lagopus) sperm motility using the ISAS® V1 CASA system.

2013

Contents Over recent years, technological advances have brought innovation in assisted reproduction to the agriculture. Fox species are of great economical interest in some countries, but their semen characteristics have not been studied enough. To advance the knowledge of function of fox spermatozoa, five samples were obtained by masturbation, in the breeding season. Kinetic analysis was performed using ISAS® v1 system. Usual kinematic parameters (VCL, VSL, VAP, LIN, STR, WOB, ALH and BCF) were considered. To establish the standardization for the analysis of samples, the minimum number of cells to analyse and the minimum number of fields to capture were defined. In the second step, the pre…

Myxoid liposarcoma of the spermatic cord: US and MR imaging findings.

2013

We report a patient with myxoid liposarcoma of the spermatic cord in whom combined use of both ultrasound (US) and MRI helped to suggest the diagnosis. The lesion was solid at US and vascularized at color Doppler. T1-weighted MRI did not show fat within it; on T2-weighted images it had high signal intensity, with a cyst-like appearance. It is known that fat-poor myxoid liposarcomas with high water content may mimic a cystic lesion on non-contrast-enhanced MR; then, a combination of MRI findings, suggesting a cyst, and of US findings, showing the mass was actually solid and vascularized, allowed preoperatively the diagnosis of fat-poor myxoid liposarcoma. © 2013 Wiley Periodicals, Inc.

Effect of frame rate capture frequency on sperm kinematic parameters and subpopulation structure definition in boars, analysed with a CASA-Mot system.

2018

Motility is the most widely used indicator of sperm quality. Computer-Assisted Semen Analysis (CASA) allows the objective evaluation of sperm motility parameters. CASA technology is a common tool to predict semen doses in farm animal reproduction. The kinds of video cameras used until now for image acquisition have presented limited frame rates (FR), which have a negative influence on the quality of the obtained data. The aim of the present work was to define the optimal frame rate for a correct evaluation of boar sperm motility and its subpopulation structure. Eighteen ejaculates from nine mature boars of the Pietrain breed were used. Using the ISAS® v1 CASA-Mot system, with a video camera…