Periconceptional folic acid supplementation reduces the occurrence of several human congenital malformations, including craniofacial, heart and neural tube defects. Although the underlying mechanism is unknown, there may be a maternal-to-fetal folate-transport defect or an inherent fetal biochemical disorder that is neutralized by supplementation. Previous experiments have identified a folate-binding protein (Folbp1) that functions as a membrane receptor to mediate the high-affinity internalization and delivery of folate to the cytoplasm of the cell. In vitro, this receptor facilitates the accumulation of cellular folate a thousand-fold relative to the media, suggesting that it may be essential in cytoplasmic folate delivery in vivo. The importance of an adequate intracellular folate pool for normal embryogenesis has long been recognized in humans and experimental animals. To determine whether Folbp1 is involved in maternal-to-fetal folate transport, we inactivated Folbp1 in mice. We also produced mice lacking Folbp2, another member of the folate receptor family that is GPI anchored but binds folate poorly. Folbp2-/- embryos developed normally, but Folbp1-/- embryos had severe morphogenetic abnormalities and died in utero by embryonic day (E) 10. Supplementing pregnant Folbp1+/- dams with folinic acid reversed this phenotype in nullizygous pups. Our results suggest that Folbp1 has a critical role in folate homeostasis during development, and that functional defects in the human homologue (FOLR1) of Folbp1 may contribute to similar defects in humans.
This investigation analyzed the effects of sport identification and brand cohesiveness as predictors of brand fit in a unique sponsorship context by examining consumer responses to event sponsorships of the Dew Action Sports Tour. An additional focus of this research endeavor assessed the impact of brand fit on two important consumer behavioral outcomes: attitude toward sponsors and purchase intentions. Data were collected from 552 attendees at the Louisville, Kentucky stop of the Dew Action Sports Tour. The results of the study support our hypotheses that fit impacts attitude toward the sponsor which has a positive influence on consumer’s purchase intentions. The examination of influence that brand cohesiveness and sport identification have on fit perceptions extends our theoretical understanding of fit in a sponsorship context as up until now, research in this area has focused almost exclusively on outcomes of fit and not on those variables that might influence fit.
The teratogenic effects of valproic acid and its 4-propyl-4-pentenoic acid (4-en) metabolite were investigated in three inbred mouse strains that were known to possess differing sensitivity to heat-induced neural tube defects. In the heat-resistant DBA/2J strain, administration of either valproic acid or the metabolite during the critical period of neural tube development failed to produce any abnormal offspring. Similar treatment in the moderately heat-sensitive LM/Bc strain resulted in up to 19.8% exencephalic fetuses. The highly heat-sensitive SWV strain was also very susceptible to the induction of neural tube defects by either valproic acid or its 4-en metabolite. When administered on gestational day 8 plus 12 hours, the parent compound produced 35% exencephalic fetuses, while the metabolite had a response frequency of 32.4%. Thus, the hierarchy of susceptibility for the induction of neural tube defects in these inbred mouse strains was exactly the same whether the teratogen was a physical agent such as hyperthermia or a chemical compound such as valproic acid. If such diverse agents as these should interact to produce malformations, then it is possible that a wide variety of other agents might interact in a similar manner to produce neural tube defects.
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