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There were also no differences in gene expression of the glucose Slc2a1 and Slc2a3 and System A amino acid transporters Slc38a1 , Slc38a2 and Slc38a4 in the placental Lz between the three groups of dams at D16 Fig. This occurred in the absence of any significant change in Slc2a1 or Slc2a3 expression in the placental Lz Fig.
An asterisk denotes significant difference from the normoxic ad libitum fed N group at the same age.
There were also no significant differences in Slc2a1 or Slc2a3 expression in the placental Lz between the three groups of dams at D19 Fig. The D19N values are identical to those shown in Fig. On D19, an asterisk denotes a significant difference from the normoxic ad libitum fed N group at the same age.
The present study demonstrates that maternal inhalation hypoxia modifies placental phenotype and maternal resource allocation to fetal growth. The placental changes were both morphological and functional in origin and occurred without any change in placental weight. The specific nature of these phenotypical changes and their effect on fetal growth depended on the timing and severity of the hypoxic insult and also, in some instances, reflected the concomitant maternal hypophagia. In addition to the changes in placental morphology induced by maternal hypoxia, there were also functional and metabolic adaptations in the placenta with consequences for resource allocation, particularly at D This suggests that adaptation of the placental System A amino acid transport system depends on the specific maternal environment and the timing of the environmental challenge.
In summary, the mouse placenta adapts to help maintain fetal growth in response to moderate but not severe hypoxia. The placenta therefore integrates these multiple signals to optimize maternal resource allocation to the fetus with respect to the prevailing environment. However, further studies are required to establish the importance of other signalling pathways and differential regulation of Akt phosphorylation at its two phosphorylation sites with respect to environmental sensing and adaptation of the placenta.
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The authors would like to thank all the staff of the animal facility for their care of the mice, as well as Nuala Daw, Melanie Monk and Emma Eastwood for their assistance with the biochemical analyses. We would also like to thank Gavin Jarvis for his statistical advice. Volume , Issue 5. If you do not receive an email within 10 minutes, your email address may not be registered, and you may need to create a new Wiley Online Library account.
Clinical Therapeutics. J Clin Immunol 16 : — These data would be very valuable for the development of new diagnosis tools, since most methods used in the national territory come from European countries and from North America and are created from regional strains, and also to allow the development of new drugs, more effective that those currently used which are not effective in many clinical situations. Philadelphia, WB Sauders Company, p. Another aspect not well publicized, not only in Brazil but around the world in general, is the matter of screening blood for toxoplasmosis, at least for immunocompromised patients and in transplant patients Vaz et al.
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Research Paper Open Access. Email: ans48 cam. This is achieved by the so-called epigenetic imprinting, a methylation de-methylation process that changes the normal functionality of a gene. By doing so, fetuses decrease their metabolic needs and thus become able to survive a a hostile environment with limited supplies.
A fetus deprived early has all the time to adapt, reduce energy demands and survive to be born alive. In contrast, a fetus deprived in the last weeks of pregnancy does not have the time to adapt and is more likely to die before birth. This is quite apparent on the demographics of fetal demise. Proportionately small babies are at increased risk of high blood pressure in adulthood but do not have an increased risk of coronary heart disease. As adults, individuals who were disproportionately short at birth tend to have abnormalities of systems controlled by the liver, and have increased rates of coronary heart disease.
These effects may be the result of adverse effects on liver development associated with central blood flow redistribution later in gestation brain sparing phenomenon.
When oxygen and energy supplies are inadequate due to placental insufficiency, the cardiovascular system distributes most of the available oxygen and nutrients to the brain, the heart and the adrenals the glands that produce the stress hormones ; the rest of the body suffers receives reduced oxygen and nutrient supplies. Neonates with a low birth weight in relation to their length skinny babies are thought to be at increased risk to develop insulin resistance and coronary heart disease in adulthood as a result of fetal under-nutrition in the weeks leading up to delivery after 28 weeks gestation.
Consistent with this, a recent follow-up study of men and women whose mothers were exposed to famine in pregnancy showed that third- trimester famine exposure resulted in impaired glucose tolerance insulin resistance in the offspring in later adult life. As might be expected, the predominant type of fetal growth restriction varies greatly in different populations. These variations may contribute to geographic differences in the prevalence of coronary heart disease. Studies of the famine of — in the Netherlands led to the rigid concept that thinness at birth results from influences operating in the last trimester of pregnancy.
Outside the setting of famine, both animal and human studies indicate that fetal under-nutrition late in pregnancy is, however, more commonly a consequence of a maternal-placental supply deficit that has its origins earlier in gestation. This is usually the result of early developmental damage to the structure, size and function of the placenta without the presence of maternal malnutrition.
Such placental deficiencies are easy to be missed prior to 28 weeks because of a unique relation between the time and rate of growth of the placenta and the time and rate of the fetus. The placenta develops and reaches almost full capacity in terms of maternal supply by weeks. Infection with either C. Cases positive for pathogenic Leptospira spp. Immunohistochemical analysis failed to visualize C. The degree of agreement between the serological and the molecular diagnostic techniques for C.
This study investigated, concomitantly, the prevalence of C.
DNA in bovine abortion material and seroconversion in affected dams and highlights the underestimation associated with using a single staining technique. Although detection of any of these pathogens does not equate invariably to causality with respect to bovine abortion, their presence does invariably represent a high zoonotic risk and a possible reservoir of infection for other animals. The frequency of antibodies specific for C. However, previous studies reported similar seropositivity for C.
With However, such high seropositivity rates have to be interpreted with caution. Firstly, a single seropositive result is not necessarily related to the etiology of the abortion and might be due to a previous exposure [ 43 ]. Secondly, serological tests may not be C. The frequency of Leptospira spp. The implication of a positive titer to serovar Hardjo on fetal loss remains controversial as many studies failed to show a causal association between seropositivity and abortion [ 22 , 45 , 46 , 47 , 48 ], while others described Hardjo as a cause of abortions [ 49 , 50 ].
The interpretation of the serological results for Leptospira spp. Although Sejroe was the second most prevalent serovar 14 cases , 12 cases were positive for serovars Hardjo and Sejroe, belonging to the same serogroup. Yet, Hardjo presented the higher titer in 10 cases making Australis six cases the second most frequent serovar. Abortion in cattle due to serovar Hardjo is a chronic event with a variable serological response at the time of abortion [ 22 ] and confirmation of infection by MAT is difficult because maternal antibody production mostly occurs prior to fetal death [ 52 ].
Molecular detection of DNA of abortifacient agents has been shown to be highly sensitive and specific [ 37 , 53 , 54 , 55 ].
By real-time PCR we detected C. These findings, although obtained with different techniques, may reflect different endemicity.
Furthermore, we showed the capacity of C. Of the 21 real-time PCR positive cases of C. In contrast, 23 cases with positive sera were negative by real-time PCR suggesting previous exposure to C. It is important to keep in mind that real-time PCR is highly sensitive and thus able to detect low levels of C.