The evolution of complex organs is a source of controversy because they require the contributions of many adaptations to function properly. We argue that placentas are complex, that they have evolved multiple times in Poeciliopsis, and that there are closely related sister taxa that have either no placentas or intermediate stages in the evolution of a placenta. Furthermore, placentas can evolve...

background: the objective of the study was to evaluate the presence of neospora caninum organisms in the brain of aborted fetuses and placentas of full-term calves born of seropositive cows. methods: during 2006-2007, 12 brains of aborted calves from neospora seropositive cattle and 7 pla­centas from seropositive dams giving birth to full-term calves, from four dairy cattle farms located around...

Preeclampsia (PE), a hypertensive disorder of pregnancy, is hypothesized to be associated with, if not mechanistically related to abnormal placental function. However, the exact mechanisms regulating the pathogenesis of PE remain unclear. While many studies have investigated changes in gene expression in the PE placenta, the role of epigenetics in PE associated placental dysfunction remains unc...

The immunological milieu in the placenta may be crucial for priming the developing foetal immune system. Early imbalances may promote the establishment of immune-mediated diseases in later life, including allergies. The initial exposure to allergens seems to occur in utero, but little is known about allergen-induced placental cytokine and chemokine release. The release of several cytokines and ...

Apoptosis and its associated regulatory mechanisms are physiological events crucial to the maintenance of placental homeostasis; imbalance of these processes, however, such as occurs under various pathological conditions, may compromise placenta function and, consequently, pregnancy success. Increased apoptosis occurs in the placentas of pregnant women with several developmental disabilities, w...

To determine the relative contributions of tobacco smoking and P-450 metabolism (cytochrome P-450iAi) in the formation of benzo(a)pyrenediol-epoxide and other polycyclic aromatic hydrocarbon-DNA adducts in vivo, 16 human placentas were assayed for aryl hydrocarbon hydroxylase activity and (±)r-7,f-8-dihydroxy-c-9,10-epoxy-7,8,9,10-tetrahydrobenzo(a)pyrene-DNA adduci levels. Immunoaffinity chro...

DNA methylation plays a critical role in the regulation of gene expression, genomic DNA stability, cell proliferation, and malignant transformation. Common cellular features including fast tissue expansion, invasive growth, and active angiogenesis, have been noticed between placental development and tumorigenesis by many investigators. While the DNA hypomethylation and transcriptional activatio...

It is postulated that inadequate remodeling of the uterine spiral arteries in preeclampsia leads to focal ischemia and generation of inflammatory cytokines, such as tumor necrosis factor (TNF alpha) and interleukins (ILs), by the placenta. Our objective was to compare TNF alpha, IL-1 alpha, IL-1 beta, and IL-6 levels in placentas from patients with preeclampsia and normal term pregnancies. Beca...

This study investigated how maternal overnutrition and obesity regulate expression and activation of proteins that facilitate lipid transport in the placenta. To create a maternal overnutrition and obesity model, primiparous C57BL/6 mice were fed a high-fat (HF) diet throughout gestation. Fetuses from HF-fed dams had significantly increased serum levels of free fatty acid and body fat. Despite ...

Glucose transporter 4 (GLUT4) protein expression was characterized in human and rodent term placentas. A 50-kDa protein was detected, by immunoblotting, in term human placenta at levels averaging 25% of those found in white adipose tissue. It was also present, albeit at lower levels, in mouse and rat placentas. The specificity of the 50-kDa signal was established by using skeletal muscle and pl...