Search results for "Embryo"

Long non-coding RNAs during embryogenesis of the sea urchin

2014

Intriguing studies suggest that long non-coding RNAs (lncRNAs) tend to act in cis with neighboring protein-coding genes. Based on this notion, we assessed whether lncRNAs originate from adjacent genomic regions of selected protein-coding genes, such as early-H2A histone and strim1, that play important functions during development of the sea urchin Paracentrotus lividus. Downregulation of H2A expression relies on the sns5 chromatin insulator placed at the 3'-end of H2A. Northern blot hybridization show that a lncRNA (of ~600 nt), not overlapping with the H2A mRNA, is transcribed from sns5, following H2A expression. The strim1 locus encodes the first echinoderm TRIM-containing factor which fu…

Geographical Variation in Egg Mass and Egg Content in a Passerine Bird

2011

Reproductive, phenotypic and life-history traits in many animal and plant taxa show geographic variation, indicating spatial variation in selection regimes. Maternal deposition to avian eggs, such as hormones, antibodies and antioxidants, critically affect development of the offspring, with long-lasting effects on the phenotype and fitness. Little is however known about large-scale geographical patterns of variation in maternal deposition to eggs. We studied geographical variation in egg components of a passerine bird, the pied flycatcher (Ficedula hypoleuca), by collecting samples from 16 populations and measuring egg and yolk mass, albumen lysozyme activity, yolk immunoglobulins, yolk and…

Sea urchin embryos as an in vivo model for the assessment of manganese toxicity: developmental and stress response effects.

2008

Manganese (Mn), one of the most abundant metals in nature present in rocks, soil and water, is also found in soft bottom sediments of the oceans. It represents a trace element that is accumulated and utilized by all forms of life and plays multiple roles ranging from bone mineralization to cellular protection. Although Mn is an essential nutrient, exposure of cells/organisms to high levels of Mn cause toxicity. In the marine environment, increased concentrations of bio-available Mn often result from anthropogenic activities, and consequently, Mn represents a new important factor in environmental contamination. Emission of Mn into the marine environment occurs from metallurgic and chemical i…

Manganese-exposed embryos as blueprints to study signaling pathways involved in development

2012

Extracellular vesicles in the human maternal-embryo crosstalk during the preconception period

2020

ANTECEDENTES: nuestro grupo demostró que el endometrio humano secreta exosomas (EXOs) al líquido endometrial (LE) con un contenido en miRNAs específico que puede ser internalizado por el embrión para favorecer la adhesión embrionaria. OBJETIVOS: definir y caracterizar los diferentes tipos de vesículas extracelulares (VEs) secretados por el endometrio humano al LE y estudiar su contenido en DNA, determinar si es internalizado por el embrión y si afecta a su regulación energética. MATERIALES Y MÉTODOS: El aislamiento de las VEs del LE se realizó mediante centrifugación diferencial. Se estudió su morfología, marcadores moleculares, tamaño y concentración a lo largo del ciclo menstrual. Su cont…

Placentofagia: moda, mit czy terapia?

2018

The article describes the increasingly popular phenomenon of placentophagy. It is becoming more and more common in the First World countries of the West, where a woman can take her placenta home after delivering a baby. It is forbidden under the Polish law. The first part of the text focuses on the origins of placentophagy, the reasons for its popularity and for showcasing motives for which people eat parts of their own bodies. The text explores opinions confirming the positive impact of placenta consumption and the medical evidence refuting the majority of these theses. The second part of the article is in turn focused on practices of treating placenta in traditional culture and the reason…

Intestinal distribution and fecundity of two species ofDiplostomumparasites in definitive hosts

2005

This paper investigated the intestinal distribution and fecundity of 2 species ofDiplostomumparasites,D. spathaceumandD. pseudospathaceum, in 2 species of definitive hosts, herring gull (Larus argentatus) and common gull (L. canus), using both empirical field data and experimental infections. At the level of individual hosts, the parasite species occupied different parts within the intestine, but the fecundity of the worms, measured as the number of eggs in the uterus, did not differ between the parasite species except in wild common gulls. Interestingly, egg numbers in individual hosts were positively correlated between the parasite species suggesting that some birds provided better resour…

The paradox of the Italian clinical embryologist in the national public health system: hints towards harmonization of a postgraduate educational curr…

2022

Clinical embryologists are highly trained laboratory professionals with multiple roles, including laboratory, clinical, biobanking and quality system management. In most European countries, clinical embryologists are trained to work in Medically Assisted Reproduction (MAR) centres without a specifically dedicated educational path. The criteria required for employment vary according to the educational structure and the public or private nature of the centre. We have herein described the educational profile required by Italian clinical embryologists to work in MAR centres of the National Health System (NHS). Public centres currently represent 36% of all the Italian MAR clinics. According to t…

Data from: Surrounding pathogens shape maternal egg care but not egg production in the European earwig

2017

Pathogens are ubiquitous in nature and typically entail major fitness costs in their hosts. These costs can be particularly important when individuals exhibit poor immune defenses, as it is often the case during early developmental stages. Hence, selection should favor parental strategies limiting the risks of pathogen exposure and infection in their offspring. In this study, we investigated 1) whether females of the European earwig Forficula auricularia avoid areas contaminated with spores of the entomopathogenic fungus Metarhizium brunneum prior to and at egg laying, as well as 2) whether spore presence entails an increase in females’ investment into both pre-hatching forms of care and cl…

Data from: Mother and offspring fitness in an insect with maternal care: phenotypic trade-offs between egg number, egg mass and egg care

2014

Background: Oviparous females have three main options to increase their reproductive success: investing into egg number, egg mass and/or egg care. Although allocating resources to either of these three components is known to shape offspring number and size, potential trade-offs among them may have key impacts on maternal and offspring fitness. Here, we tested the occurrence of phenotypic trade-offs between egg number, egg mass and maternal expenditure on egg care in the European earwig, Forficula auricularia, an insect with pre- and post-hatching forms of maternal care. In particular, we used a series of laboratory observations and experiments to investigate whether these three components n…