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Pregnancy in pigs includes the events of conceptus (embryo/fetus and placental membranes) elongation, implantation, and placentation. Placentation in pigs is defined microscopically as epitheliochorial and macroscopically as diffu...
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Pregnancy in pigs includes the events of conceptus (embryo/fetus and placental membranes) elongation, implantation, and placentation. Placentation in pigs is defined microscopically as epitheliochorial and macroscopically as diffuse. In general, placentation can be defined as the juxtapositioning of the endometrial/uterine microvasculature to the chorioallantoic/placental microvasculature to facilitate the transport of nutrients from the mother to the fetus to support fetal development and growth. Establishment of epitheliochorial placentation in the pig is achieved by: (1) the secretions of uterine glands prior to conceptus attachment to the uterus; (2) the development of extensive folding of the uterine–placental interface to maximize the surface area for movement of nutrients across this surface; (3) increased angiogenesis of the vasculature that delivers both uterine and placental blood and, with it, nutrients to this interface; (4) the minimization of connective tissue that lies between these blood vessels and the uterine and placental epithelia; (5) interdigitation of microvilli between the uterine and placental epithelia; and (6) the secretions of the uterine glands, called histotroph, that accumulate in areolae for transport though the placenta to the fetus. Placentation in pigs is not achieved by invasive growth of the placenta into the uterus. In this chapter, we summarize current knowledge about the major events that occur during the early stages of implantation and placentation in the pig. We will focus on the microanatomy of porcine placentation that builds off the excellent histological work of Amoroso and others and provide a brief review of some of the key physiological, cellular, and molecular events that accompany the development of “implantation” in pigs.
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There is an increasing awareness of the deleterious effects attributed to mycotoxins during their fate within the gut, particularly for deoxynivalenol (DON), zearalenone (ZEN), ochratoxin A (OTA), fumonisin B1 (FB1), aflatoxin B1 ...
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There is an increasing awareness of the deleterious effects attributed to mycotoxins during their fate within the gut, particularly for deoxynivalenol (DON), zearalenone (ZEN), ochratoxin A (OTA), fumonisin B1 (FB1), aflatoxin B1 (AFB1), and patulin (PAT). Evidence indicates that disruption of the epithelial barrier is well established. However, intestinal barrier function on its luminal side involves two other partners, mucus and microbiota, which have rarely been considered in the context of mycotoxin exposure. The current review aimed at providing a summary of DON, ZEN, OTA, FB1, AFB1, and PAT effects on intestinal barrier function, with special focus on mucus and microbiota. DON, ZEN, OTA, FB1, AFB1, and PAT are known to markedly affect epithelial cell integrity and functions. Regarding mucus, DON is the most documentated mycotoxin. In vivo, toxicological impact of DON generally has only been assessed through goblet cell number. Evaluation of the mycotoxins/mucus interplay considering other indicators such as composition, thickness, and penetrability of mucus, mucin O-glycosylation thus warrants further attention. With respect to microbiota, few short-term studies to date have been reported indicating deleterious effects. However, long-term exposure to mycotoxins may also produce significant changes in microbiota composition and metabolic activity, which requires further experimentation. In conclusion, mucus and microbiota are key targets for dietary mycotoxins although assessment of induced effects is preliminary. A significant research effort is now underway to determine the adverse consequences of mycotoxins on mucus and microbiota considered as individual but also as tightly connected gut players.
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A metal-free catalytic method for the synthesis of 2-deoxy glycosides and disaccharides has been developed using stable 2-deoxy glucosyl and galactosyl acetate donors. They could react with a variety of acceptors in the presence o...
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A metal-free catalytic method for the synthesis of 2-deoxy glycosides and disaccharides has been developed using stable 2-deoxy glucosyl and galactosyl acetate donors. They could react with a variety of acceptors in the presence of catalytic amount of TMSOTf at 0癈 to form glycosides, glycoconjugates, and disaccharides with excellent ?selectivity (> 19:1) and yields (up to 99%) in a short time (0.5 h). With this expedient method, several new compounds against human K562 and SMMC7721 cell lines were obtained and tested with in vitro antitumor bioactivities.
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AP@LZ is an electronic organiser that was designed to support the day-to-day activities of persons with Alzheimer's disease. To assess the potential of this technology, three participants (NI, JB, RD) were approached to take part ...
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AP@LZ is an electronic organiser that was designed to support the day-to-day activities of persons with Alzheimer's disease. To assess the potential of this technology, three participants (NI, JB, RD) were approached to take part in the study. They benefited from a structured cognitive intervention to learn how to operate AP@LZ; the intervention included the following learning stages: Acquisition, Application and Adaptation. Pre- and post-intervention measures were collected. NI, for whom a longitudinal study was conducted, still continued to use AP@LZ 24 months post-intervention. JB and RD also showed a gradual improvement in their performance throughout the intervention phase (sessions 1 to 19 for JB: performance increased from 50 to 100%; sessions 1 to 25 for RD: from 56 to 89%). The results of the use of AP@LZ in activities of daily living suggest that the application was beneficial for three persons with Alzheimer's disease whose profiles differed notably (age, cognitive and social profiles). Thus, results indicate that they were all able to learn how to operate AP@LZ's functions and to use them in their activities of daily living. Cognitive intervention appears to play an important role for the promotion of learning and adoption of such technology.
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