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Zhonghua Fu Chan Ke Za Zhi Nov 1989Ten term pregnancy placentas from preeclampsic cases, uncomplicated by essential hypertension, IUGR or renal disease were studied by means of histomorphometric analysis...
Ten term pregnancy placentas from preeclampsic cases, uncomplicated by essential hypertension, IUGR or renal disease were studied by means of histomorphometric analysis and the results were compared with 10 term pregnancy normal placentas. There was no significant statistical difference in the parameters between the two groups. In the membrane rolls and in a portion of placental bed biopsies from preeclampsic patients there was no acute atherosis in the spiral arteries. This study demonstrated that, the morphological and functional changes in the placentas of preeclampsia yielded little effect on fetal growth and that acute atherosis in spiral artery was not pathognomonic of preeclampsia.
Topics: Arteries; Female; Humans; Placenta; Pre-Eclampsia; Pregnancy
PubMed: 2632161
DOI: No ID Found -
Histology and Histopathology Apr 2017The placenta, which is a regulator organ for many metabolic activities between mother and fetus, is critical in influencing the outcome of pregnancy. Therefore, fetal... (Review)
Review
The placenta, which is a regulator organ for many metabolic activities between mother and fetus, is critical in influencing the outcome of pregnancy. Therefore, fetal growth is directly related to the placental development. Placental development depends on the coordinated action of trophoblast proliferation, differentiation and invasion. Studies on cell cycle related proteins that control these events are limited. Abnormal placental development is linked to various pregnancy pathologies such as preeclampsia, intrauterine growth restriction, diabetes mellitus and gestational trophoblastic diseases. The cell cycle mechanism of human placenta should be well understood for a healthy pregnancy outcome. Moreover, how cell cycle related proteins that control placental development are affected in pregnancy pathologies is not fully understood yet. Therefore, the aim of this review is to address the currently available knowledge on cell cycle regulatory proteins involved in human placental development and on the expression differences of these proteins in pathological placentas.
Topics: Cell Cycle Proteins; Female; Humans; Placenta; Placentation; Pregnancy
PubMed: 27665761
DOI: 10.14670/HH-11-832 -
Placenta Sep 2000Paracellular pathways in the haemotrichorial placenta of the rat were studied by electron microscopy using lanthanum hydroxide as an electron dense marker. Near term...
Paracellular pathways in the haemotrichorial placenta of the rat were studied by electron microscopy using lanthanum hydroxide as an electron dense marker. Near term placentae were dually perfused in situ, adding lanthanum to the fetal perfusate. In some placentae outflow pressure on the fetal side was elevated (between 10 and 25 cm H(2)O) to promote filtration of fluid in a fetomaternal direction. Under normal pressure conditions lanthanum particles lined the subendothelial spaces and tubular structures in the inner, syncytial layer of trophoblast. Further penetration of lanthanum into the tubules was blocked by coarse lanthanum aggregates. Elevated fetal hydrostatic pressure resulted in a fluid shift across the placenta (filtration rate 50+/-16 per cent of fetal arterial inflow rate), distending the tubules in the inner trophoblast layer. Lanthanum particles gradually appeared in tubular structures in the middle (syncytial) layer and in the lateral intercellular spaces in the outer (cellular) layer. Finally lanthanum reached the maternal surface of the trophoblast. These pressure effects were only partially reversible. When the fetal pressure was returned to control values, some distension of the tubules persisted and the entire length of the paracellular pathways remained accessible to lanthanum. It is concluded that the placental barrier in the rat contains pressure dependent paracellular pathways connecting the maternal and fetal extracellular compartments.
Topics: Animals; Blood Pressure; Chemical Precipitation; Female; Fetus; Hydrostatic Pressure; Indicators and Reagents; Lanthanum; Maternal-Fetal Exchange; Microscopy, Electron; Placenta; Pregnancy; Rats; Trophoblasts; Umbilical Veins
PubMed: 10985970
DOI: 10.1053/plac.2000.0558 -
Placenta 2004Until recently, tenrecs were classified with insectivores in the order Lipotyphla, but nucleotide sequence data suggest they have closer affinities with a group of...
Until recently, tenrecs were classified with insectivores in the order Lipotyphla, but nucleotide sequence data suggest they have closer affinities with a group of African mammals called Afrotheria. The placenta of Echinops has not been described and no studies involving electron microscopy of the placenta of any species of tenrec have been published. We used light and transmission electron microscopy to examine fixed placentae of embryos ranging from 25-66 mm in length. The placental disk is situated in the antimesometrial portion of the bicornuate uterus. The greater part of the disk consists of a labyrinth underlain by a spongy zone. The interhaemal barrier is unusual in that the trophoblastic component is a single layer of cytotrophoblast. These trophoblast cells have thick areas especially near the nuclei and extensive thin flanges but only occasionally have membrane-closed pore regions. The luminal surface has isolated patches of microvilli, and pinocytotic vesicles are numerous both apically and basally. In the centre of the placental disk is an elaborately folded haemophagous region. The primary folds have allantoic endoderm at one surface and columnar cytotrophoblast at the other. These trophoblast cells have numerous lipid droplets and vesicles, and often contain large yellow pigment crystalloids. The labyrinthine zone ends abruptly at the margins of the placental disk. However, the endoderm and connective tissue of the allantois and a layer of cytotrophoblast extend beyond the placental disk as a paraplacental region. Some of these distinctive features of Echinops placenta are shared with individual afrotherians, but no significant characteristic of definitive placentation is shared by all the Afrotheria.
Topics: Animals; Eulipotyphla; Female; Microscopy, Electron; Placenta; Pregnancy
PubMed: 14972454
DOI: 10.1016/j.placenta.2003.08.009 -
The Kobe Journal of Medical Sciences Feb 1994Morphological studies were done on 109 placentae of 6 to 43 gestational weeks. Soft x-ray figures are useful for detecting the development of the placenta, which is...
Morphological studies were done on 109 placentae of 6 to 43 gestational weeks. Soft x-ray figures are useful for detecting the development of the placenta, which is closely correlated to enlargement of cotyledon and vascular growth in the chorionic villi. At histological figures, chorionic villi, corresponding to intermediate mature villi at the early gestational weeks, reveal large size with edematous stroma and prominent interstitial cells. Their size becomes smaller with aging, with decreased interstitial cells and stroma. At the early gestational period until 23 weeks, chorionic villi are lined by two cell layers of S-(syncytial) and C-(cytotrophoblastic) cells. After 24 gestational weeks C-inner lining decreases in number. Syncytial knots become marked after 32 weeks. As aging, the intervillous space becomes narrow and is occupied by the small sized terminal and mature chorionic villi with congestive capillaries. Syncytial knots and fibrin deposit around chorionic villi are increased with placental aging. By the immunohistoenzymatical examination, S-lining is positive by hCG (human Chorionic Gonadotropin) at the early gestation, but is markedly positive by hPL(human Placental Lactogen) and SP-1 (Specific Protein 1) lately.
Topics: Chorionic Villi; Female; Gestational Age; Humans; Placenta; Placentation; Radiography
PubMed: 8035558
DOI: No ID Found -
The Journal of Veterinary Medical... Nov 2008In order to investigate the morphological effects of ketoconazole on hypertrophied placentas, we examined the sequential histopathological changes in the placenta from...
In order to investigate the morphological effects of ketoconazole on hypertrophied placentas, we examined the sequential histopathological changes in the placenta from rats exposed to ketoconazole. Ketoconazole was administered orally at 0 and 25 mg/kg/day during gestation days (GDs) 12 to 14, and the placentas were sampled on GDs 15, 17 and 21. All dams showed neither effect on body weight nor any abnormal clinical signs during the experimental period. In the treated group, the placentas appeared more hypertrophic with increases in the weight, diameter and thickness on GD 21. Histopathologically, increased thickness was noted in the labyrinth zone and basal zone on GDs 17 and 21, while on GD 15 the change had been already evident in the former zone. In the labyrinth zone, the mitotic figures of the trophoblasts were significantly elevated on GD 15. A multiple cystic dilatation of maternal sinusoids was observed in some placentas on GDs 15, 17 and 21. In the basal zone, an increase in spongiotrophoblasts and clusters of glycogen cells were detected on GDs 17 and 21. In the decidua basalis, there were no significant changes in either histology or thickness between the control and treated group during GDs 15 to 21. In conclusion, ketoconazole increased the population of composed cells in the labyrinth and basal zone, leading to placental hypertrophy in pregnant rats.
Topics: Animals; Apoptosis; Decidua; Female; Fetal Death; Ketoconazole; Mitosis; Organ Size; Placenta; Pregnancy; Rats
PubMed: 19057135
DOI: 10.1292/jvms.70.1179 -
American Journal of Reproductive... 1993Investigations to date on localization of placental insulin receptors (IR) at the ultrastructural level focused on the maternal facing side of the placenta but did not...
PROBLEM
Investigations to date on localization of placental insulin receptors (IR) at the ultrastructural level focused on the maternal facing side of the placenta but did not allow localization of IRs to intracellular compartments.
METHOD
The ultrastructural localization of IR in placentae from early and term gestation was studied using the immunogold technique and a monoclonal antibody against the external domain of the IR (clone MA20).
RESULTS
At 10 wk gestation, there were high levels of IR in both cytotrophoblast and syncytiotrophoblast, with sparse microvillous labeling. Fetal vessels contained various amounts of IR while stromal cells were also labeled. By 13 wk, this pattern was unchanged; however, at term, fewer IR were present in the syncytiotrophoblast, with more label on microvilli than before. Fetal vessels were well labeled, while stromal cells appeared unchanged. Intense labeling of fetal erythrocytes provided an internal positive control, while omission of the primary antiserum produced loss of binding.
CONCLUSION
The data suggest a spatiotemporal alteration in placental IR distribution during pregnancy, possibly reflecting a shift in control of placental growth and metabolism from mother to fetus.
Topics: Chorionic Villi; Female; Humans; Immunohistochemistry; Placenta; Pregnancy; Receptor, Insulin; Trophoblasts
PubMed: 8311922
DOI: 10.1111/j.1600-0897.1993.tb00614.x -
Placenta 1983Six placentae from small for gestational age infants were examined by both light and electron microscopy. These were from pregnancies in which all maternal or fetal...
Six placentae from small for gestational age infants were examined by both light and electron microscopy. These were from pregnancies in which all maternal or fetal factors known to be associated with intrauterine growth retardation, including maternal cigarette smoking, were excluded. At the light microscopic level the only significant finding was an excess of villous cytotrophoblastic cells whilst electron microscopy showed these placentae to be characterized by villous cytotrophoblastic hyperplasia, focal syncytial necrosis, microvillous abnormalities, reduced syncytial secretory activity, irregular thickening of the trophoblastic basement membrane and the presence of small fetal villous vessels with multilayered basement membranes. It is thought that most of the observed abnormalities are due to uteroplacental ischaemia and it is possible that the fetal vascular abnormalities are a reflection of the fetal growth retardation. There is little evidence that the functional efficiency of the placenta is impaired in these cases and it is suggested that the principal factor in the pathogenesis of fetal growth retardation is a restriction of nutrient supply to the fetus because of an inadequate degree of physiological change within the maternal spiral vessels.
Topics: Adult; Basement Membrane; Chorionic Villi; Female; Fetal Growth Retardation; Humans; Infant, Newborn; Infant, Small for Gestational Age; Placenta; Pregnancy; Trophoblasts
PubMed: 6856589
DOI: 10.1016/s0143-4004(83)80018-6 -
Journal of Comparative Pathology Jan 2019The aim of this study was to describe the lectin-binding pattern in the placentas of cows infected experimentally with Neospora caninum. Four cows were inoculated...
The aim of this study was to describe the lectin-binding pattern in the placentas of cows infected experimentally with Neospora caninum. Four cows were inoculated intravenously with 1 × 10 tachyzoites of the NC-1 strain of N. caninum at 150 ± 7 days of pregnancy. Two control cows were administered a placebo. An indirect fluorescence antibody test (IFAT) was performed on serum samples obtained before and after the inoculation. The cows were killed at 30 and 37 days post inoculation. Samples of placenta were taken for histopathology and lectin histochemistry. Fetal tissues and fluids were collected for histopathology and IFAT, respectively. All infected cows had high antibody titres. All fetuses had characteristic histopathological lesions, including non-suppurative meningoencephalitis, myocarditis, hepatitis and myositis, suggesting N. caninum infection. Only two infected fetuses developed specific antibodies. Mild non-suppurative inflammatory infiltrates were recorded in the placentae. Differences in the lectin-binding pattern were observed between infected animals and controls in the glycocalyx (CON-A and WGA) and apical cytoplasm (RCA-I and CON-A) of the trophoblastic cells; giant trophoblastic cells (CON-A and DBA); glycocalyx (PNA, WGA) and apical cytoplasm (CON-A, WGA, PNA, DBA and RCA-I) of endometrial cells; trophoblast of the interplacentomal region (WGA); endothelium (CON-A, SBA, RCA-1 and WGA); and finally, mesenchyme (CON-A, RCA-1, SBA, PNA and DBA). These findings indicate that there is a distinctive pattern of lectin binding in the placenta of cattle infected with N. caninum. The direct effect of the presence of the protozoa as well as the altered expression of cytokines could explain these changes in the maternofetal interface.
Topics: Animals; Cattle; Cattle Diseases; Coccidiosis; Female; Fluorescent Antibody Technique, Indirect; Lectins; Neospora; Placenta; Pregnancy
PubMed: 30691605
DOI: 10.1016/j.jcpa.2018.10.172 -
Nature Communications Mar 2024Accurate placenta pathology assessment is essential for managing maternal and newborn health, but the placenta's heterogeneity and temporal variability pose challenges...
Accurate placenta pathology assessment is essential for managing maternal and newborn health, but the placenta's heterogeneity and temporal variability pose challenges for histology analysis. To address this issue, we developed the 'Histology Analysis Pipeline.PY' (HAPPY), a deep learning hierarchical method for quantifying the variability of cells and micro-anatomical tissue structures across placenta histology whole slide images. HAPPY differs from patch-based features or segmentation approaches by following an interpretable biological hierarchy, representing cells and cellular communities within tissues at a single-cell resolution across whole slide images. We present a set of quantitative metrics from healthy term placentas as a baseline for future assessments of placenta health and we show how these metrics deviate in placentas with clinically significant placental infarction. HAPPY's cell and tissue predictions closely replicate those from independent clinical experts and placental biology literature.
Topics: Infant, Newborn; Humans; Pregnancy; Female; Placenta; Deep Learning
PubMed: 38548713
DOI: 10.1038/s41467-024-46986-2