Search results for "fertilization"

Extensive nuclear gyration and pervasive non-genic transcription during primordial germ cell development in zebrafish.

2020

ABSTRACT Primordial germ cells (PGCs) are the precursors of germ cells, which migrate to the genital ridge during early development. Relatively little is known about PGCs after their migration. We studied this post-migratory stage using microscopy and sequencing techniques, and found that many PGC-specific genes, including genes known to induce PGC fate in the mouse, are only activated several days after migration. At this same time point, PGC nuclei become extremely gyrated, displaying general broad opening of chromatin and high levels of intergenic transcription. This is accompanied by changes in nuage morphology, expression of large loci (PGC-expressed non-coding RNA loci, PERLs) that ar…

APOPTOTIC ANALYSIS OF CUMULUS CELLS FOR THE SELECTION OF COMPETENT OOCYTES TO BE FERTILIZED BY INTRACYTOPLASMIC SPERM INJECTION (ICSI)

2015

Oocyte quality is one of the main factors for the success of in vitro fertilization protocols. Apoptosis is known to affect oocyte quality and may impair subsequent embryonic development and implantation. The aim of this study was to investigate the apoptosis rate of single and pooled cumulus cells of cumulus cell–oocyte complexes (COCs), as markers of oocyte quality, prior to intracytoplasmatic sperm injection (ICSI).We investigated the apoptosis rate by TUNEL assay (DNA fragmentation) and caspase-3 immunoassay of single and pooled cumulus cells of COCs. The results showed that DNA fragmentation in cumulus cells was remarkably lower in patients who achieved a pregnancy than in those who di…

Impact on ICSI outcomes of adding 24 h of in vitro culture before testicular sperm freezing: a retrospective study.

2015

To compare sperm parameters and intracytoplasmic sperm injection (ICSI) outcomes for testicular spermatozoa frozen on the day of the biopsy (DO) with those frozen after 24 h of in vitro culture (D1).In this retrospective study, from 1999 to 2012, forty-nine azoospermic patients were included to compare sperm (motility and viability) and outcomes (fertilization (FR), implantation (IR), pregnancy (PR) and delivery rates (DR)).The in vitro culture increased total motility (+2.8 %, p = 0.0161) but decreased viability (-8.3 %, p = 0.007). After 24 h of culture, the post-thaw changes in motility and viability were not significant. Twenty-six couples underwent ICSI: thirty-four ICSI were performed…

Human Oviductal Gonadotropin-Releasing Hormone: Possible Implications in Fertilization, Early Embryonic Development, and Implantation1

2000

The oviduct is host to gametes and early embryos at a critical point in their lives. It is clear that the interactions of gametes/early embryo with the maternal oviduct in an autocrine and paracrine manner provide a microenvironment that enhances fertilization, early embryonic development, and implantation. Moreover, there is considerable evidence that an extrahypothalamic GnRH may play a substantial role as a molecular autocrine/paracrine regulator in these events. Gametes and preimplantation embryos express GnRH and GnRH receptor at both messenger ribonucleic acid (mRNA) and protein levels. However, whether GnRH is produced by the human oviduct has not yet been demonstrated. We used RT-PC…

Effect of potassium fertilization on the hydraulic conductance of laurel plants

2009

The effect of potassium fertilization on hydraulic conductance was tested in 2-year-old potted laurel seedlings, grown in a greenhouse at the Botanical Garden of Palermo. Plants were divided into a control group (+K) and a potassium starved group (-K). A set of randomly chosen -K plants received irrigation with 25 mM KCl (KCl plants) 24 hours before measurements, to test the short term effect of potassium fertilization. Measurements were carried out in July and October 2008. Whole-plant hydraulic conductance was measured by the evaporative flux method; root and shoot hydraulic conductance were measured by the vacuum chamber. Potassium availability or season did not significantly affect leaf…

Phosphate-Nitrogen fertilizatio effect on faba bean bioagronomic response

2007

Effect of foliar nutrition on olive oil characteristics in cv 'Nocellara del Belice'

2008

How much can regional agri-environmental measures contribute to SOC stocking in the soils of Sicily?

2014

Soils have a great potential in stocking soil organic carbon SOC, but how much can human activities, and particularly agricultural ones, contribute to increase (or decrease) the SOC content? Which kind of agricultural practices are the most effective? From the soil database of Sicily we have selected 52 profiles, whose first 40 cm from the soil surface were analyzed for the SOC, of which 15 analyzed also for nitrogen N content, localized in the clayey hills and limestone marine terraces of the western Sicily, cultivated with grain crops and orchards (mainly olive groves and vineyards), surveyed and analyzed in a period from 1995 to 2008. By interviews to the farmers owners of those parcels,…

SOME COMPARATIVE REMARKS ON THE TRANSIENT CHANGE IN LACTIC ACID CONTENT IN SEA URCHIN EGGS FOLLOWING FERTILIZATION.

1964

Abstract During the first few minutes following fertilization a transient increase in the concentration of lactic acid occurs in the eggs of Arbacia lixula , whereas no change at all is observed in the eggs of Paracentrotus liuidus . In the eggs of Psammechinus miliaris there is a transient decrease, soon followed by a recovery so that the level of the unfertilized egg is again reached.

Management of irrigation water and nutrient demands of tomato (Lycopersicon esculentum Mill.) using urban treated wastewater from a pilot-scale horiz…

2017

The reuse of treated wastewater (TWW) in crop irrigation is an advanced and rational approach to water resource management in agriculture. Results would seem to demonstrate that it could be an extremely important tool in the reduction of freshwater (FW) consumption in agriculture, at the same time helping to increase crop yields through the transfer of nutrients required for crop growth. In arid and semi-arid areas of the Mediterranean, constructed wetlands can play a key role in the treatment and reuse of wastewater due to their multifunctional nature. The aim of this study was to manage water and nutrient requirements of tomato (Lycopersicon esculentum Mill.) using TWW from a pilot-scale …