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International audience; Massive proliferation of some toxic marine dinoflagellates is responsible for the occurrence of harmful algal blooms and the contamination of fish and shellfish worldwide. Pinnatoxins (PnTx) (A-H) comprise an emerging phycotoxin family belonging to the cyclic imine toxin group. Interest has been focused on these lipophilic, fast-acting and highly potent toxins because they are widely found in contaminated shellfish, and can represent a risk for seafood consumers. PnTx display a potent antagonist effect on nicotinic acetylcholine receptors (nAChR), and in this study we assessed in vivo the ability of PnTx-G to cross physiological barriers to reach its molecular target. Radiolabeled [3H]-PnTx-G synthesized with good radiochemical purity and yield retained the high affinity of the natural toxin. Oral gavage or intravenous administration to adult rats and digital autoradiographic analyses revealed the biodistribution and toxicokinetics of [3H]-PnTx-G, which is rapidly cleared from blood, and accumulates in the liver and small intestine. The labeling of peripheral and brain adult/embryo rat tissues highlights its ability to cross the intestinal, blood-brain and placental barriers. High-resolution 3D-imaging and in vitro competition studies on rat embryo sections revealed the specificity of [3H]-PnTx-G binding and its selectivity for muscle and neuronal nAChR subtypes (such as α7 subtype). The use of a human perfused cotyledon model and mass spectrometry analyses disclosed that PnTx-G crosses the human placental barrier. The increasing worldwide occurrence of both the dinoflagellate Vulcanodinium rugosum and PnTx-contaminated shellfish, due to climate warming, raises concerns about the potential adverse impact that exposure to pinnatoxins may have for human health.

L’incontinence urinaire d’effort est l’incontinence la plus fréquente chez la femme. Le sujet principal de cette revue de la littérature porte sur l’efficacité des différentes méthodes intra-cavitaires, dans la prise en charge ré-éducative de cette pathologie.

The human placenta is at the interface between maternal and fetal circulations, and is crucial for fetal development. The nanoparticles of cerium dioxide (CeO2 NPs) from air pollution are an unevaluated risk during pregnancy. Assessing the consequences of placenta exposure to CeO2 NPs could contribute to a better understanding of NPs&rsquo, effect on the development and functions of the placenta and pregnancy outcome. We used primary villous cytotrophoblasts purified from term human placenta, with a wide range of CeO2 NPs concentrations (0.1&ndash, 101 &mu, g/cm2) and exposure time (24&ndash, 72 h), to assess trophoblast uptake, toxicity and impact on trophoblast differentiation and endocrine function. We have shown the capacity of both cytotrophoblasts and syncytiotrophoblasts to internalize CeO2 NPs. CeO2 NPs affected trophoblast metabolic activity in a dose and time dependency, induced caspase activation and a LDH release in the absence of oxidative stress. CeO2 NPs decreased the fusion capacity of cytotrophoblasts to form a syncytiotrophoblast and disturbed secretion of the pregnancy hormones hCG, hPL, PlGF, P4 and E2, in accordance with NPs concentration. This is the first study on the impact of CeO2 NPs using human primary trophoblasts that decrypts their toxicity and impact on placental formation and functions

International audience; Controlled distribution of a drug by its association to a nanocarrier is a promising approach for the treatment of pregnancy disorders such as preeclampsia. For this application, tracking both the nanocarrier and the drug is necessary to ensure the safety of both the mother and the foetus. This study reports a method to visualize and quantify the uptake of liposomal formulations in placental tissue using florescent labelling and appropriate analytical tools. Lipoplexes were labelled with a fluorescent lipid, DOPE-NBD while the encapsulated siRNA was fluorescently labelled with rhodamine. Lipoplexes were incubated with villous placenta explants, explants were imaged with confocal microscopy, then DOPE-NBD was extracted from the explant and quantified by HPLC. Qualitative evaluation by confocal microscopy showed the presence of lipoplexes and siRNA into the outer layer of the placental explants, the syncytiotrophoblast. For quantitative evaluation, an HPLC method for the quantification of fluorescent lipid DOPE-NBD in placental tissue was developed and validated. The developed method was applied to quantify the DOPE-NBD uptake in the placental tissue. Increased amounts of DOPE-NBD were detected in placental explants when increasing the incubation concentration of lipoplexes. This study provides a method to evaluate the interactions between liposomal formulation and the placental barrier.

Dissertação de mestrado em Tecnologia e Ciência Alimentar, Desde sempre que a alimentação, a segurança e qualidade alimentar constituem uma preocupação à humanidade. As mudanças da sociedade nos hábitos de vida, de rotina e de alimentação resultaram na alteração das preferências dos consumidores. Atualmente, o consumidor opta por produtos de rápida confeção, como também tem havido uma maior preocupação e exigência em termos da segurança e qualidade dos produtos. O principal objetivo estabelecido para a presente dissertação consiste no controlo da qualidade e segurança alimentar numa unidade de produção (2ª transformação) de refeições e acompanhamentos de arroz esterilizados. Recentemente, a empresa Ernesto Morgado, S.A ficou certificada pela IFS Food, que exige o controlo e verificação do processo produtivo, garantindo a qualidade e segurança dos produtos comercializados, bem como a satisfação dos consumidores. Assim sendo, o estágio centrou-se no acompanhamento na unidade industrial nas diversas etapas de fabrico, de forma a controlar os potenciais perigos alimentares, desde a receção das matérias-primas até à expedição do produto acabado. Para além disso, realizaram-se atividades de rotina no laboratório de qualidade e segurança alimentar da empresa, relativamente à matéria-prima e ao produto acabado. No laboratório efetuaram-se controlos à estabilidade do produto e à integridade das embalagens, para além da inspeção visual de metais, do controlo sensorial do lote de fabrico e da verificação de potenciais resíduos de alergénios., Nutritious food, food safety and quality have always been a concern for everyone involved in food systems. Changes in society, lifestyle, routines, food habits dictated consumer’s preferences. Today, consumers choose convenience and ready-to-eat food products though, increasingly demanding for higher levels of safety and quality. The main objective established for this dissertation was to assess the controls of food safety and quality in the production (2nd processing) of sterilized meals and side dishes based on rice. Recently, the company Ernesto Morgado S.A., has been certified by IFS Food, which requires the control and verification of the production process, ensuring the quality and safety of marketed products, as well as, consumer satisfaction. Accordingly, the internship focused on monitoring the procedures established in the industrial unit at the various stages of manufacture, in order to control potential food hazards, from raw materials receiving to shipping of the finished product. In addition, routine activities were carried out in the company's food quality and safety laboratory for raw material and finished product. Laboratory controls were performed on product stability, packaging integrity, visual inspection of metals, sensory analysis of the production batches and checking for residues of allergens.

International audience; The chorionic villus of the human placenta is the source of specific endocrine functions and nutrient exchanges. These activities are ensured by the syncytiotrophobast (ST), which bathes in maternal blood. The ST arises and regenerates throughout pregnancy by fusion of underlying cytotrophoblasts (CT). Any anomaly of ST formation or regeneration can affect pregnancy outcome and fetal growth. Because of its direct interaction with maternal blood, the ST is sensitive to drugs, pollutants and xenohormones. Ex vivo assays of perfused cotyledon show that formaldehyde, a common pollutant present in furniture, paint and plastics, can accumulate in the human placenta and cross to the fetal compartment. By means of RT-qPCR, immunoblot and immunocytochemistry experiments, we demonstrate in vitro that formaldehyde exerts endocrine toxicity on human trophoblasts, including a decrease in the production of protein hormones of pregnancy. In addition, formaldehyde exposure triggered human trophoblast fusion by upregulating syncitin-1 receptor expression (ASC-type amino-acid transporter 2: ASCT2). Moreover, we show that formaldehyde-exposed trophoblasts present an altered redox status associated with oxidative stress, and an increase in ASCT2 expression intended to compensate for this stress. Finally, we demonstrate that the adverse effects of formaldehyde on trophoblast differentiation and fusion are reversed by N-acetyl-L-cysteine (Nac), an antioxidant.