-
PloS One 2019Plasmodium (P.) falciparum malaria during pregnancy has been frequently associated with severe consequences such as maternal anemia, abortion, premature birth, and...
Plasmodium (P.) falciparum malaria during pregnancy has been frequently associated with severe consequences such as maternal anemia, abortion, premature birth, and reduced birth weight. Placental damage promotes disruption of the local homeostasis; though, the mechanisms underlying these events are still to be elucidated. Autophagy is a fundamental homeostatic mechanism in the natural course of pregnancy by which cells self-recycle in order to survive in stressful environments. Placentas from non-infected and P. falciparum-infected women during pregnancy were selected from a previous prospective cohort study conducted in the Brazilian Amazon (Acre, Brazil). Newborns from infected women experienced reduced birth weight (P = 0.0098) and placental immunopathology markers such as monocyte infiltrate (P < 0.0001) and IL-10 production (P = 0.0122). The placentas were evaluated for autophagy-related molecules. As a result, we observed reduced mRNA levels of ULK1 (P = 0.0255), BECN1 (P = 0.0019), and MAP1LC3B (P = 0.0086) genes in placentas from P. falciparum-infected, which was more striking in those diagnosed with placental malaria. Despite the protein levels of these genes followed the same pattern, the observed reduction was not statistically significant in placentas from P. falciparum-infected women. Nevertheless, our data suggest that chronic placental immunopathology due to P. falciparum infection leads to autophagy dysregulation, which might impair local homeostasis during malaria in pregnancy that may result in poor pregnancy outcomes.
Topics: Adolescent; Adult; Autophagy; Down-Regulation; Female; Humans; Placenta; Plasmodium falciparum; Pregnancy; RNA, Messenger; Young Adult
PubMed: 31805150
DOI: 10.1371/journal.pone.0226117 -
AJR. American Journal of Roentgenology Jun 1997We determined the accuracy of prenatal sonography for detecting placental circumvallation, a placental abnormality associated with increased fetal morbidity and... (Comparative Study)
Comparative Study
OBJECTIVE
We determined the accuracy of prenatal sonography for detecting placental circumvallation, a placental abnormality associated with increased fetal morbidity and mortality.
MATERIALS AND METHODS
We analyzed 62 healthy pregnant (range, 18-36 weeks) patients with focused placental sonography for detection of morphologic abnormality using the published criteria for circumvallate placenta (irregular edge, uplifted margin, or placental sheet or shelf). Placental marginal sonograms were taken at 30 degrees intervals around the entire placental margin. Five experienced sonologists who were unaware of the pathologic findings independently reviewed the placental images and graded the placentas from 1 (definitely normal) to 5 (definitely circumvallate). Receiver operating characteristic (ROC) curves and area under the ROC curve were calculated for each reader. Gross and microscopic pathology was used as the gold standard for all cases.
RESULTS
In the 62 patients, sonography revealed 49 normal placentas (79%), 12 partially circumvallate placentas (19%), and one completely circumvallate placenta (2%). ROC curves for the reviewers resulted in values for area under the curve ranging from .39 to .58. The sonologist who achieved the highest value for the area under the curve classified the 13 cases of proven circumvallation as one case of definite circumvallation, four cases as uncertain or equivocal, and eight cases as probably or definitely normal placentas. Of the normal placentas, 35% were graded as probably or definitely circumvallate by at least one sonologist. All sonologists misgraded the case of complete circumvallation as normal.
CONCLUSION
Focused placental sonograms interpreted by experienced sonologists fail to detect the placental edge abnormality in most cases of circumvallation. In our study, 17 of 49 normal placentas were diagnosed as probably or definitely circumvallate by one or more observers. Our sonologists' interpretations of sonograms showed that complete circumvallation was difficult to assess. Although our study had a limited number of patients, the accuracy of sonography of the placenta for revealing circumvallation appears to be limited.
Topics: Case-Control Studies; Female; Humans; Placenta; Placenta Diseases; Predictive Value of Tests; Pregnancy; Pregnancy Outcome; ROC Curve; Ultrasonography, Prenatal
PubMed: 9168736
DOI: 10.2214/ajr.168.6.9168736 -
Placenta Mar 2013This review covers four topics. 1) Placental pathology in Himalayan mountain people. To determine morphological changes of the placenta at high altitude, pathological... (Review)
Review
This review covers four topics. 1) Placental pathology in Himalayan mountain people. To determine morphological changes of the placenta at high altitude, pathological examination was made of 1000 Himalayan placentas obtained in Nepal and Tibet and the results compared with Japanese placentas delivered at sea level. Characteristic findings in the placental villi of the Himalayan group included high incidences of villous chorangiosis and chorangioma. These processes were clarified by ultrastructural observation. 2) Placentation in Sirenians. The giant Takikawa sea cow, which lived 5 million years ago, was discovered on Hokkaido, Japan. It was an ancestor of the dugong as well as the manatees. Sirenia, the sea cow group, shares a common ancestor with Proboscidea, the elephants, even though they now inhabit quite different environments. A comparison was made of their zonary endothelial type of placentation. 3) Placentation in sharks and rays. The remarkable placentation of hammerhead sharks and manta rays is described. 4) Placentation in the Antarctic minke whale. Placental tissue samples of this whale were obtained from the Japan Institute of Cetacean Research. In an ultrastructural study of the utero-placental junction, microfilamental processes of the allantochorionic zone and crypt formation were visualized.
Topics: Animals; Dugong; Female; Humans; Japan; Oceans and Seas; Placenta; Placentation; Pregnancy; Pregnancy, Animal; Species Specificity
PubMed: 23332416
DOI: 10.1016/j.placenta.2012.11.021 -
Placenta Dec 2013Placental glutamine synthesis has been demonstrated in animals and is thought to increase the availability of this metabolically important amino acid to the fetus.... (Comparative Study)
Comparative Study
INTRODUCTION
Placental glutamine synthesis has been demonstrated in animals and is thought to increase the availability of this metabolically important amino acid to the fetus. Glutamine is of fundamental importance for cellular replication, cellular function and inter-organ nitrogen transfer. The objective of this study was to investigate the role of glutamate/glutamine metabolism by the isolated perfused human placenta in the provision of glutamine to the fetus.
METHODS
Glutamate metabolism was investigated in the isolated dually perfused human placental cotyledon. U-¹³C-glutamate was used to investigate the movement of carbon and ¹⁵N-leucine to study movement of amino-nitrogen. Labelled amino acids were perfused via maternal or fetal arteries at defined flow rates. The enrichment and concentration of amino acids in the maternal and fetal veins were measured following 5 h of perfusion.
RESULTS
Glutamate taken up from the maternal and fetal circulations was primarily converted into glutamine the majority of which was released into the maternal circulation. The glutamine transporter SNAT5 was localised to the maternal-facing membrane of the syncytiotrophoblast. Enrichment of ¹³C or ¹⁵N glutamine in placental tissue was lower than in either the maternal or fetal circulation, suggesting metabolic compartmentalisation within the syncytiotrophoblast.
DISCUSSION
Placental glutamine synthesis may help ensure the placenta's ability to supply this amino acid to the fetus does not become limiting to fetal growth. Glutamine synthesis may also influence placental transport of other amino acids, metabolism, nitrogen flux and cellular regulation.
CONCLUSIONS
Placental glutamine synthesis may therefore be a central mechanism in ensuring that the human fetus receives adequate nutrition and is able to maintain growth.
Topics: Amino Acid Transport Systems, Neutral; Biological Transport; Carbon Isotopes; Cell Membrane; Female; Fetal Development; Glutamic Acid; Glutamine; Humans; In Vitro Techniques; Kinetics; Leucine; Maternal-Fetal Exchange; Models, Biological; Nitrogen Isotopes; Perfusion; Placenta; Placental Circulation; Pregnancy; Trophoblasts
PubMed: 24183194
DOI: 10.1016/j.placenta.2013.10.003 -
Archives of Gynecology and Obstetrics Feb 2003Recent studies described the presence of elastic fibres within stem villi of human term placenta. This particular study focuses on changes of the elastic fibre system in...
Recent studies described the presence of elastic fibres within stem villi of human term placenta. This particular study focuses on changes of the elastic fibre system in placental villous tree from placentas of different gestational ages. The presence of elastic fibres was researched by light and electron microscopy in first-, second-trimester and term human placentas. Light microscopic analysis revealed elastic fibres in the stroma of main stem villi and in large vessels present in the chorionic plate of term placentas. Transmission electron microscopy revealed a wide variation in microfibrillar component deposition in placentas from all the gestational ages studied. Although minimal amount of the microfibrillar component was observed only in some main stem villi of second-trimester placentas, abundant microfibrillar material was present in all types of placental villi in placental sections from term pregnancies. The amorphous component was only occasionally identified in sections from the chorionic plate of second trimester placentas. In ultra-thin sections from placental tissues from the 37th to the 42nd weeks of gestation, we can observe the amorphous component of the elastic fibres. Bundles of microfibrils with scanty participation of the amorphous component of the elastic fibres can be observed in stem villi. In mature intermediate villi, cells and their processes with distinct plasma membranes were seen close to some bundles of microfibrillar component, at times with small spots of the amorphous component. This study shows that elastic fibres of the villous stroma, are mainly composed of the microfibrillar component, while the amorphous component appears more frequently in advanced stages of villous differentiation of term placentas.
Topics: Elastic Tissue; Female; Gestational Age; Humans; Microscopy, Electron; Muscle Fibers, Skeletal; Placenta; Pregnancy; Pregnancy Trimesters
PubMed: 12592420
DOI: 10.1007/s00404-002-0314-7 -
Early Human Development Jun 1984Ninety five placentae from normal term and 'normal' preterm pregnancies have been analysed by morphometry. The growth of the whole placenta, of the microscopic placental...
Ninety five placentae from normal term and 'normal' preterm pregnancies have been analysed by morphometry. The growth of the whole placenta, of the microscopic placental constituents and of the villous surface area has been measured in placentae from uncomplicated pregnancies from 10 weeks of gestation to term to provide data for comparison with values from placentae from pathological pregnancies. No evidence for placental senescence is found in the placentae from normal pregnancies up to term although the rate of growth of the villous surface area decreases gradually from approximately 34 weeks gestation. Evidence is given to suggest that in normal pregnancy villi continue to elaborate until term. The relationship of villous surface area to fetal growth is assessed.
Topics: Chorionic Villi; Female; Fetus; Gestational Age; Growth; Humans; Placenta; Pregnancy
PubMed: 6745150
DOI: 10.1016/0378-3782(84)90074-4 -
The American Journal of Surgical... Aug 1998Massive chronic intervillositis (MCI) is an infrequently recognized placental lesion thought to be of immunologic origin that has been associated with poor fetal...
Massive chronic intervillositis (MCI) is an infrequently recognized placental lesion thought to be of immunologic origin that has been associated with poor fetal outcome. It is characterized by a prominent inflammatory infiltrate in the intervillous space, composed mainly of monocytes and macrophages that can simulate a maternal malignant disorder involving the placenta. The villi are characteristically spared. We report 74 cases of placental malarial infection with morphologic features of MCI. In all cases, the massive inflammatory infiltrate was limited to the intervillous space, which appeared largely obliterated. Increased fibrin deposition and prominent syncytial knots were frequent associated findings. Inflammatory cells were CD45 and CD68 positive, consistent with a monocyte-macrophage population. Some polymorphonuclear leukocytes and scattered T and B lymphocytes were also present. Villi were not inflamed. Malarial pigment was present in all cases, and parasitized maternal erythrocytes were evident in 73 of 74 patients. The histologic pattern of MCI was observed in 17.6% of placentas with malarial parasites. Malarial MCI affected predominantly primigravida women (77%) and was associated with a reduced birth weight, which in 39 (53%) of the infants was less than 2500 g, and a low gestational age. None of the infants with placentas with MCI died in the early neonatal period. Morphologic changes of MCI are seen in a significant percentage of placentas with malarial infection, especially in primigravida women, and are associated with a low birth weight. Malarial infection should therefore be considered in the differential diagnosis of massive intervillous infiltrates.
Topics: Chorionic Villi; Chronic Disease; Female; Humans; Immunohistochemistry; Inflammation; Malaria; Placenta; Pregnancy; Pregnancy Complications, Parasitic
PubMed: 9706981
DOI: 10.1097/00000478-199808000-00011 -
Placenta Mar 2008This workshop focused on describing clinical problems identified in the placentae of cloned animals and some of the potential biological mechanisms by which these...
This workshop focused on describing clinical problems identified in the placentae of cloned animals and some of the potential biological mechanisms by which these anomalies arise. It was shown that placental anomalies related to somatic cell nuclear transfer (SCNT) in cattle often can be detected by ultrasonography early in gestation, enabling preventive clinical intervention. On the mechanistic front, the vascular defects in the placenta appear to be associated with anomalies in the expression of VEGF system, which could lead to the aberrant placentomes and generalized oedema seen in some gestations. Moreover, an upstream transcription factor (Mash2) controlling the differentiation of trophoblast into binucleate cells may be involved in the poor implantation rates of SCNT embryos. Finally, epigenetic patterns in placenta can be disrupted by fairly simple in vitro manipulations, which could explain the extreme anomalies observed in the placenta of SCNT pregnancies.
Topics: Animals; Cloning, Organism; Education; Female; Placenta; Placental Insufficiency; Pregnancy
PubMed: 18281092
DOI: 10.1016/j.placenta.2007.11.010 -
Biology of Reproduction Feb 1996Despite the amazing diversity of placental architecture across species, a number of common elements can be found, including the ability of all placentae to synthesize... (Review)
Review
Despite the amazing diversity of placental architecture across species, a number of common elements can be found, including the ability of all placentae to synthesize and metabolize steroid hormones; the assignment of steroidogenic activities to specific trophoblast phenotypes; the use of novel mechanisms to control expression of steroidogenic enzyme genes, which differ from those employed in the adrenal cortex and gonads; and interactions with the maternal and fetal compartments encompassing supply of steroid hormone precursors as well as regulatory influences of maternal ovarian and pituitary hormones and fetal adrenal cortical steroids.
Topics: Animals; Female; Fetus; Humans; Placenta; Pregnancy; Steroids; Trophoblasts
PubMed: 8788180
DOI: 10.1095/biolreprod54.2.303 -
Gynecologic and Obstetric Investigation 198061 placentae were submitted to a study in vitro after deliveries. The ultrasonographic scanning was performed under the condition of immersing them in water and then...
61 placentae were submitted to a study in vitro after deliveries. The ultrasonographic scanning was performed under the condition of immersing them in water and then comparing their images with the anatomical structure by cutting the placentae corresponding to the scanning line. Histological examinations were performed to confirm the anatomical structure. The ultrasonographic findings were classified in 5 types and their correlation with fetal maturity and fetal distress is discussed.
Topics: Adult; Female; Fetal Distress; Gestational Age; Humans; In Vitro Techniques; Placenta; Pregnancy; Pregnancy Complications; Ultrasonography
PubMed: 7450569
DOI: 10.1159/000299846