Search results for "fertilization"

Noble gas and CO2 isotopic signatures of the lithospheric mantle underneath Mexico and the Canary Islands: clues from mantle xenoliths and arc lavas

2022

Studying the isotopic composition of fluids trapped in mantle xenoliths opens avenues to understand the origin and cycling of volatiles in the Earth’s upper mantle. In this PhD dissertation, new and in most cases the very first data regarding the isotopic (noble gases and CO2) characterization of the lithospheric mantle portions of three different geodynamic environments are presented: (i) Central and NW Mexico, a continental setting dominated by extension; (ii) the Transmexican Volcanic Belt (TMVB) a subduction setting, and (iii) the Canary Islands, particularly El Hierro and Lanzarote, two oceanic islands formed by mantle plume-derived intraplate volcanism. In total 32 peridotites (includ…

A Primary Evaluation of Potential Small-Molecule Inhibitors of the Astacin Metalloproteinase Ovastacin, a Novel Drug Target in Female Infertility Tre…

2020

Abstract Despite huge progress in hormonal therapy and improved in vitro fertilization methods, the success rates in infertility treatment are still limited. A recently discovered mechanism revealed the interplay between the plasma protein fetuin‐B and the cortical granule‐based proteinase ovastacin to be a novel key mechanism in the regulation of fertilization. Upon sperm–egg fusion, cleavage of a distinct zona pellucida component by ovastacin destroys the sperm receptor, enhances zona robustness, and eventually provides a definitive block against polyspermy. An untimely onset of this zona hardening prior to fertilization would consequently result in infertility. Physiologically, this proc…

The pre-zygote identity as a moral issue.

2008

Inhibitor of the Cytochrome Oxidase of Unfertilized Sea Urchin Eggs

1960

IN a previous communication1 the presence of an inhibitor of cytochrome oxidase in the unfertilized sea urchin egg was described. It was shown that its activity decreases considerably following fertilization, that it is a low-molecular compound, that it is heat- and alkali-labile and that its action is of a competitive type.

Nitrous oxide emission by agricultural soils: a review of spatial and temporal variability for mitigation

2012

CT3 ; EnjS4; International audience; This short review deals with soils as an important source of the greenhouse gas N2O. The production and consumption of N2O in soils mainly involve biotic processes: the anaerobic process of denitrification and the aerobic process of nitrification. The factors that significantly influence agricultural N2O emissions mainly concern the agricultural practices (N application rate, crop type, fertilizer type) and soil conditions (soil moisture, soil organic C content, soil pH and texture). Large variability of N2O fluxes is known to occur both at different spatial and temporal scales. Currently new techniques could help to improve the capture of the spatial va…

Mir-661: A key Factor in Embryo-Maternal dialog With Potential Clinical Application to Predict Implantation Outcome?

2015

Implantation resulting in a full-term pregnancy is, by large, more than a passive process in which the developed conceptus is passively glued to the uterus through adhesive molecules. It is the result of a perfectly orchestrated dialog between a viable embryo and a receptive endometrium, through a mixture of paracrine and juxtacrine processes in which many key proteins and growth factors play fundamental roles (Pellicer et al., 2002.) Since their discovery, microRNAs have become prominent regulatory candidates, providing missing links for a few biological pathways in this process, although their exact role in human normal embryo formation and endometrial preparation for pregnancy remains un…

Effects of Organic and Chemical N-fertilization on Yield and Morpho-biological Features in Coriander (Coriandrum sativum L.).

2009

Although MAPs are subjected to a growing interest (from growers, transformation industries, public and private institutions), a full introduction of such species into the Mediterranean cropping systems still needs the pointing out of many aspects. An important task concerns some aspects of cropping technique, whose definition could allow these crops to optimize the yields (both from the qualitative and the quantitative point of view), also allowing the best exploitation of land resources. One of the most crucial aspects is linked to plant fertilization, above all with Nitrogen. The trial that we report the results of has been performed in 2003- 04 and 2004-05 with the aim to study the effec…

Bioindicators and nutrient availability through whole soil profile under orange groves after long-term different organic fertilizations

2019

We investigated long-term (18 years) effects of three organic (cow manure (CM), poultry manure (PM), compost from agro-industry orange wastes (OW)) and one inorganic fertilization (IF) on various soil biological indicators (microbial biomass C, soil respiration, total phospholipid fatty acids (PLFAs), total bacteria, Gram-positive and Gram-negative bacteria and fungi) and nutrient contents (total and extractable organic C, total and mineral N, available P and K) along the profile of a Typic Haplustept under orange Mediterranean orchards. All fertilizers were added on the same N content basis (190 kg N ha−1 per year). Variables related to carbon cycling gradually worsened with depth, regardl…

Unpredicted ovulations and conceptions during early pregnancy: an explanatory mechanism of human superfetation

2012

In this bioessay, a literature review on human superfetation was performed in order to find epidemiological variables associated with this phenomenon. Thereafter, an explanatory mechanism of superfetation compatible with the endocrinological, histological and physiological changes undergone by women during early pregnancy is proposed. Superfetation can be defined as the ovulation, fertilisation and implantation of a second or additional embryo(s) during pregnancy. The literature review evidences a small discordance in gestational age between dizygotic twins in humans (range: 2–4 weeks; mean ± s.e.m.: 3.3 ± 0.3 weeks). This difference is compatible with a luteal out-of-phase (LOOP; i.e. atyp…

Oxidative homeostasis in follicular fluid and reproductive outcomes – from bench to bedside

2022

Free radicals and oxidant molecules are part of our organism in a stable balance. However, when addressing female infertility, questions about their role in oocyte quality arise. This review outlines the major alterations of redox homeostasis in the follicular fluid through pathophysiological conditions in female reproduction and its potential effect on IVF outcome. A review of the literature was accurately performed. Manuscripts investigating follicular fluid biomarkers, especially related to oxidant molecules, were screened and used in this review. Studies assessing the follicular reactive species were found and screened. Moreover, studies assessing the IVF outcomes related to biomarkers …