Comparative analysis of trophoblasts and angiogenesis in human placental compartments / Análisis comparativo de trofoblastos y angiogénesis en compartimentos placentarios humanos

SUMMARY: Trophoblasts perform different functions depending on their location. This study aimed to obtain structural clues about the functions of villous and extravillous trophoblasts by using light and electron microscopy. Term placenta samples were obtained from 10 healthy pregnant women following cesarean sections. Frozen sections were stained with hematoxylin-eosin, semi- thin sections were stained with toluidine blue and examined with a light microscope, while thin sections were contrasted using uranyl acetate-lead citrate and evaluated under an electron microscope. Fine structural features of villous trophoblasts overlapped some villous stromal cells. In addition to the usual appearance of mature capillaries in villous stroma, we demonstrated and reported maturational stages of angiogenetic sprouts in term placenta. Extravillous trophoblasts were classified according to their location: fibrinoid, chorion, trophoblastic, column, maternal vascular endothelium, or decidua. All of these trophoblasts shared some ultrastructural features but also were distinct from each other. In decidua, it was noted that the endothelial lining of some vessels was invaded by a few endovascular trophoblasts with irregular microvilli. These cells shared some ultrastructural properties with both villous trophoblasts and stromal cells. Examination showed that angiogenesis was still present in term placentas and that trophoblasts, endothelial and stromal cells have very similar properties ultrastructurally, suggesting they represent transformational forms.

RESUMEN: Los trofoblastos dependiendo de su ubicación realizan diferentes funciones. Este estudio tuvo como objetivo obtener pistas estructurales sobre las funciones de los trofoblastos vellosos y extravellosos mediante el uso de microscopía óptica y electrónica. Se obtuvieron muestras de placenta a término de 10 mujeres embarazadas sanas después de cesáreas. Las secciones congeladas se tiñeron con hematoxilina-eosina, las secciones semidelgadas se tiñeron con azul de toluidina y se examinaron con un microscopio óptico, mientras que las secciones delgadas se contrastaron con acetato de uranilo-citrato de plomo y se evaluaron con un microscopio electrónico. Las finas características estructurales de los trofoblastos vellosos se superponen a algunas células estromales vellosas. Además de la apariencia habitual de capilares maduros en el estroma velloso, demostramos e informamos etapas de maduración de brotes angiogenéticos en la placenta a término. Los trofoblastos extravellosos se clasificaron según su localización: fibrinoide, corion, trofoblástico, columna, endotelio vascular materno o decidua. Todos estos trofoblastos compartían algunas características ultraestructurales, pero también eran distintos entre sí. En decidua se observó que el revestimiento endotelial de algunos vasos estaba invadido por unos pocos trofoblastos endovasculares con microvellosidades irregulares. Estas células compartían algunas propiedades ultraestructurales tanto con los trofoblastos vellosos como con las células del estroma. El examen mostró que la angiogénesis todavía estaba presente en las placentas a término y que los trofoblastos, las células endoteliales y estromales tienen propiedades ultraestructurales muy similares, lo que sugiere que representan formas de transformación.

Characteristics of the equine placenta at first trimester / Características de la placenta equina en el primer trimestre

The equine placenta is a simple apposition of fetal and maternal tissues, becoming more complex with the formation of microcotyledons around days 75 and 100 of gestation. The present study aimed to describe the gross and microscopic morphology of early equine placenta. Embryonic/fetal membranes from thirty-seven mares were submitted to macroscopic description, light, scanning and transmission microscopy. Overall the gross characteristics of membranes were similar with already described for older stages. However, transmission electron microscopy evidenced high metabolic rate in chorion and allantois, and high secretion profile in amnion and even higher in yolk sac. Gene ontologies enrichment, using published data, pointed several common ontologies in allantoic and amniotic fluids, related to oxygen and iron transport, extracellular space and high-density lipoprotein receptor binding. Overall, the morphological and ontology enrichment could indicate allantois and amnion crosstalk.

La placenta equina es una simple aposición de tejidos fetales y maternos, que se vuelve más compleja con la formación de microcotiledones alrededor de los días 75 y 100 de gestación. El presente estudio tuvo como objetivo describir la morfología macroscópica y microscópica de la placenta equina temprana. Las membranas embrionarias / fetales de treinta y siete yeguas fueron sometidas a descripción macroscópica, luz, escaneo y microscopía de transmisión. En general, las características generales de las membranas fueron similares a las ya descritas para las etapas más antiguas. Sin embargo, la microscopía electrónica de transmisión mostró una alta tasa metabólica en corion y alantoides, y un alto perfil de secreción en amnios e incluso mayor en el saco vitelino. El enriquecimiento de ontologías génicas, utilizando datos publicados, señaló varias ontologías comunes en fluidos alantoideos y amnióticos, relacionados con el transporte de oxígeno y hierro, espacio extracelular y unión a receptores de lipoproteínas de alta densidad. En general, el enriquecimiento morfológico y ontológico podría indicar alantoides y diafonía de amnios.

Distribution of 5-methylcytosine and 5-hydroxymethylcytosine in bovine fetal tissue of the placenta / Distribuição de 5-metilcitosina e 5-hidroximetilcitosina em placenta fetal bovina

5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC) are modified cytosines found in mammals that are involved in the regulation of gene expression. The aim of this study was to characterize the global patterns of 5-mC and 5-hmC of the fetal placenta of Nellore cattle as well as blood and sperm as controls. 5-mC and 5-hmC levels were determined using MethylFlash Methylated/Hydroxymethylated DNA Quantification Kit, respectively. Placenta tissues showed lower levels of 5-mC and 5-hmC compared to sperm. The male cotyledon showed higher levels of 5-hmC than the female. For the first time, the levels of 5-mC and 5-hmC in Bos taurus indicus were characterized, which may contribute to our understanding of the mechanisms of epigenetic regulation in the placenta. The presence of 5-hmC in somatic tissues suggest that 5-hmC has its own biological function and it is not only a byproduct from the oxidation of 5-mC. These results may be of interest in ARTs, especially in cloning in the diagnosis/prognosis of aberrant placentation and the viability of pregnancies.(AU)

5-metilcitosina (5-mC) e 5-hidroximetilcitosina (5-hmC) são citosinas modificadas encontradas nos mamíferos que estão envolvidas com a regulação da expressão gênica. O objetivo do presente estudo foi caracterizar os padrões globais de 5-mC e 5-hmC em placenta fetal de animais da raça Nelore, assim como em sangue e espermatozoides, usados como controles. Os níveis de 5-mC e 5-hmC foram determinados usando os kits MethylFlash Methylated/Hydroxymethylated DNA Quantification, respectivamente. Tecidos placentários apresentaram menores níveis de 5-mC e 5-hmC quando comparados com espermatozoides. Cotilédones de machos apresentaram maiores níveis de 5-hmC do que os de fêmeas. Os níveis de 5-mC e 5-hmC em animais Bos taurus indicus foram caracterizados pela primeira vez, o que pode contribuir para o nosso conhecimento sobre a regulação dos mecanimos epigenéticos na placenta. A presença de 5-hmC em tecidos somáticos sugerem que essa base pode ter sua própria função biológica, sendo não somente um sub-produto da oxidação da 5-mC. Esses resultados podem ser de interesse nas Tecnologias de Reprodução Assistida, especialmente na clonagem, no diagnóstico/prognóstico de placentação aberrante e viabilidade da progênie.(AU)

Ultrastructure of bovine placenta during all gestational period / Ultraestrutura de placenta bovina durante todo o período gestacional

Placentas from pregnant cows with different gestation periods were used. Placental fragments of all groups were processed and evaluated by transmission electron microscopy. After fragment analysis, bovine placenta was observed to be epitheliochorial type in early pregnancy, becoming progressively sinepiteliocorial at the beginning of the second trimester. There are no ultrastructural evidences of inflammation in the region of caruncles throughout gestation, despite the invasion of caruncle proper lamina by trophoblast cells. However, throughout pregnancy and especially at the end, there were evident signs of cell degeneration in both trophoblast and the uterine epithelium. The active trophoblast cells intensely phagocytize cellular debris. There are complex interdigitations between the surface of the trophoblast and the uterine epithelium, which is related to the increase of the exchange surface between mother and fetus. At the end of pregnancy, interdigitations disappear, favoring the detachment and expulsion of the placenta after birth.(AU)

Foram utilizadas placentas de vacas abatidas em frigorífico com diversos tempos gestacionais. Fragmentos de placentomo de todos os grupos foram processados e avaliados em microscopia eletrônica de transmissão. Após análise dos fragmentos, observou-se que a placenta bovina é do tipo epiteliocorial no início da gestação, tornando-se sinepiteliocorial progressivamente a partir do início do segundo mês de gestação. Não existem evidências ultraestruturais de inflamação na região das carúnculas durante toda a gestação, apesar da invasão da lâmina própria caruncular por células trofoblásticas. No entanto, durante toda a gestação e em especial ao seu final, foram observados sinais evidentes de degeneração celular, tanto do trofoblasto como do epitélio uterino. As células trofoblásticas ativas fagocitam intensamente os debris celulares originados dessas degenerações. Existem complexas interdigitações entre a superfície do trofoblasto e do epitélio uterino, o que estaria relacionado com o aumento da superfície de troca entre mãe e feto. Ao final da gestação, praticamente desaparecem essas interdigitações, favorecendo o descolamento e a expulsão da placenta após o parto.(AU)

Immunophenotyping of leukocytes in bovine placenta / Imunofenotipagem de leucócitos na placenta bovina

Lymphocytes and macrophages are the main white cells involved in fetal-maternal tolerance. Little is known about these leukocytes in bovine placenta, such as the quantity and location of these cells. Thus, the objective of this study was to identify lymphocyte and macrophage populations in bovine placenta using specific markers and flow cytometry. This study analyzed samples of placentomes and intercaruncular regions of cows in the three quarters of pregnancy. In the placentomes, during the first quarter of pregnancy, mean percentage of labeled CD3+ cells was 2.34%; CD8+, 1.28%; CD14+, 1.66%; and CD335+, 0.96%. For the intercaruncular region, percentage of CD3+ cells was 0.71%; CD8+, 1.63%; CD14+, 2.81%; and CD335+, 2.81%. In the second quarter, placentomes showed 0.94% CD3+ cells; 0.77% CD8+; 0.72% CD14+; and 0.51% CD335+. In the intercaruncular region, percentage of labeled CD3+ cells was 0.50%; CD8+, 1.81%; CD14+, 2.64%; and CD335+, 0.51%. In the third quarter, placentomes showed labeling of 0.88% CD3+; 0.66% CD8+; 1.06% CD14+; and 0.74% CD335+ cells. In the intercaruncular region, percentage of labeled CD3+ cells was 0.19%; CD8+, 2.23%; CD14+, 2.43%; and CD335+, 0.16%. The results showed that there was a greater immunomarking of leukocytes CD3+ and CD335+ in the placentome when compared to the intercaruncular region during the third trimester. It can be concluded that leukocytes populations in bovine placenta is reduced, probably because of the syndesmochorial characteristic of bovine placenta. This represents a significant barrier for the immunological system of the mother, sharply decreasing the exposure of the conceptus to the mother's immune system.(AU)

Linfócitos e macrófagos são os principais leucócitos envolvidos na tolerância materno-fetal. Pouco se sabe sobre esses leucócitos na placenta bovina, como por exemplo, a quantidade e localização dessas células. Assim, o objetivo desse estudo foi identificar populações de linfócitos e macrófagos na placenta bovina utilizando marcadores específicos e citometria de fluxo. Este estudo analisou amostras de placentônios da região intercaruncular de bovinos nos três trimestres da gestação. No primeiro trimestre, nos placentônios, a porcentagem média de células CD3+ foi 2,34%; CD8+, 1,28%; CD14+, 1,66%; e CD335+, 0,96%. Na região intercaruncular, a porcentagem de células CD3+ foi 0,71%; CD8+, 1,63%; CD14+, 2,81%; e CD335+, 2,81%. No segundo trimestre, os placentônios apresentaram 0,94% de células CD3+; 0,77% de CD8+; 0,72% de CD14+e 0,51% de CD335+. Na região intercaruncular, a porcentagem de células CD3+ foi 0,50%; CD8+, 1,81%; CD14+, 2,64%; e CD335+, 0,51%. No terceiro trimestre, os placentônios apresentaram 0,88% de células marcadas CD3+; 0,66% de CD8+; 1,06% de CD14+ e 0,74% de CD335+. Na região intercaruncular, a porcentagem de células CD3+ foi 0,19%; CD8+, 2,23%; CD14+, 2,43% e CD335+, 0,16%. Os resultados mostraram que a imunomarcação de leucócitos na região do placentônio foi maior do que na região intercaruncular no terceiro trimestre. Concluiu-se que a população de leucócitos CD3+ e CD335+ na placenta bovina está reduzida, provavelmente devido à sua característica sindesmocorial. Essa característica representa uma barreira significante para o sistema imunológico da mãe, o que diminui drasticamente a exposição do concepto ao sistema de defesa da mãe.(AU)

Expression of VEGF and CD68 in the placenta of gestational diabetic mothers (immunohistochemistry and ultrastructural study) / Expresión de VEGF y CD68 en la placenta de madres diabéticas gestacionales (estudio inmunohistoquímico y ultraestructural)

Placental angiogenesis, is essential for embryonic and fetal development. In this study, 18 gestational diabetes mellitus and 22 control pregnancies were included. Gestational diabetes mellitus (GDM) groups compared to the control group significantly higher values were detected (p<0.01). The following histological results were assessed; villous immaturity, chorangiosis, presence of, sncytial knots,mononuclear cell infiltration ischemia and fibrinoid necrosis. To evaluate and compare the placental histology of normal and GDM pregnancies. placentas of pregnant women with gestational diabetes also in terms of angiogenesis and macrophages and ultratructural revealed by examining the possible relationship between fetal complications were investigated.

La angiogénesis de la placenta es esencial para el desarrollo embrionario y fetal. En este estudio, se incluyeron 18 casos de diabetes mellitus gestacional (DMG) y 22 embarazos de control. En grupos los de DMG en comparación con el control, se detectaron valores significativamente mayores (p<0,01) en los siguientes parámetros histológicos que fueron evaluados: inmadurez vellosa, chorangiosis, presencia de nodos sincicial, infiltración celular isquémica mononuclear y necrosis fibrinoide. La investigación de las placentas de mujeres con DMG, reveló mediante el examen en términos de angiogénesis, macrófagos y ultraestructural, la posible relación entre las complicaciones fetales.

Ultrastructural changes in the placental membrane in pregnancies associated with diabetes / Cambios ultraestructurales en la membrana placentaria en embarazos asociados con la diabetes

Placenta is the most accurate record of the infant prenatal experience. If the placenta is examined minutely after delivery, it provides much insight into the prenatal health of the baby and the mother. The weight of placenta is higher in diabetic pregnancy in comparison to the normal pregnancy. To study the cellular changes that might contribute to more weight of placenta in diabetic pregnancies, light microscopic and electron microscopic analysis was performed. Twenty singleton pregnancies complicated with Gestational diabetes mellitus (12 controlled on diet, 8 controlled on insulin) were selected and compared to control group. Tissue sections were processed and analyzed. The placenta of diabetic pregnancies showed no abnormality on gross observation but light microscopic examination revealed, lesions like syncytial knots, fibrinoid necrosis, villous edema, villous fibrosis and capillary proliferation. Transmission electron microscopic examination (TEM) showed changes in almost all the layers of the placental membrane i.e. synctiotrophoblast, cytotrophoblast, trophoblastic basement membrane and fetal capillaries. These changes were observed in the placenta of both groups of patients whether blood sugar level was controlled by diet or insulin, but to different degree. It indicates that control of hyperglycemia only partially prevents the development of placental abnormalities which must be due to some other constituent factor of diabetic state.

La placenta es el registro más preciso de la experiencia prenatal infantil. Si la placenta se examina minuciosamente después del parto, ésta proporciona una visión más acabada de la salud prenatal de la madre y el bebé. El peso de la placenta es mayor en el embarazo con diabetes en comparación con el embarazo normal. Para estudiar los cambios celulares que podrían contribuir a un mayor peso de la placenta en los embarazos diabéticos, se llevó a cabo un análisis a través de microscopía óptica y electrónica. Fueron seleccionados 20 embarazos únicos complicados con diabetes mellitus gestacional (12 controlados por dieta, 8 controlado por insulina) y comparados con un grupo control. Las muestras de tejido fueron procesadas y analizadas. La placenta de los embarazos diabéticos no mostró ninguna anormalidad macroscópica, pero el examen por microscopía de luz reveló lesiones como nudos sinciciales, necrosis fibrinoide, edema velloso, fibrosis de las vellosidades y proliferación capilar. La microscopía electrónica de transmisión (TEM) mostró cambios en casi todas las capas de la membrana sincitiotrofoblástica, es decir, la placenta, citotrofoblasto, membrana basal trofoblástica y capilares fetales. Estos cambios se observaron en la placenta de ambos grupos de pacientes donde el nivel de azúcar en la sangre se controló mediante dieta o insulina, pero en grado diferente. Esto indica que el control de la hiperglicemia sólo impide parcialmente el desarrollo de anormalidades en la placenta, las cuales deben ser causadas por algún otro factor constituyente del estado diabético.

Expression of death cellular receptors FAS/CD95 and DR4 during porcine placentation / Expresión de los receptores de muerte celular FAS/CD95 y DR4 durante la placentación porcina

Apoptosis is a permanent and dynamic physiological process by which an organism eliminates the undesirable cells without causing an inflammatory response. The objective of this work was to study the expression of FAS, DR4 and other members of the TNF-R1 superfamily extrinsic route apoptotic receptors the DNA fragmentation and the cellular apoptosis in placental samples at the early, mid and late pregnancy on +/- 30, +/- 55 and +/- 114 gestational days, respectively. We used placental histological sections of samples fixed in buffered saline formaldehyde. Immunohistochemical techniques were performed to detect the apoptotic receptors, whereas the DNA fragmentation was detected by TUNEL reaction and apoptotic cellular ultrastructure was detected by TEM conventional techniques. Apoptosis related receptors were immunolocalized in the early pig gestation and correlated with apoptosis, suggesting a role in the cellular remodelling of the placenta. At gestation day 55, apoptosis might be correlated to FAS route, but not by DR4-mediating pathway. At the end of gestation, increased apoptosis and both receptors markers were detected showing cellular death due to the extrinsic route through FAS and DR4 receptors. In conclusion, the immunolocalization of FAS and TNF R-1 receptors along the pig placental development correlates with TUNEL reaction and with apoptotic ultrastructure observed by TEM and seems to occur through different pathways along gestation.

La apoptosis es un proceso fisiológico, dinámico y permanente a través del cual un organismo elimina células indeseables sin provocar una respuesta inflamatoria. El objetivo del presente trabajo fue estudiar la expresión de los receptores de la vía extrínseca de apoptosis, FAS, DR4 y otros miembros de la superfamilia TNF-R1, la fragmentación del ADN y la apoptosis celular a través de TEM, en muestras placentarias del inicio, la mitad y el final de la gestación, hacia el día +/- 30, +/- 55 y +/- 114 de preñez, respectivamente. Se realizaron cortes histológicos de las muestras placentarias fijadas en formol tamponado. Para la detección de los receptores de apoptosis se realizaron técnicas inmunohistoquímicas, para el estudio de la fragmentación del ADN se utilizó el ensayo TUNEL y para el análisis de la ultraestructura celular apoptótica la técnica convencional de TEM. La inmunolocalización de los receptores de muerte celular al inicio de la preñez porcina sugiere el rol de la apoptosis en la remodelación celular placentaria. Hacia el día 55 de preñez, la apoptosis detectada ocurriría únicamente a través de la vía del receptor FAS, no del receptor DR4. Al final de la gestación, se detectó un incremento de la apoptosis y la expresión de ambos receptores, indicando que la muerte celular a través de la vía de señalización extrínseca estaría inducida por los receptores FAS y DR4. En conclusión, la inmunolocalización de los receptores FAS y otros miembros del TNF-R1, los resultados de TUNEL y la ultraestructura celular apoptótica observada en la placentación porcina, indican que la apoptosis detectada ocurre por diferentes vías de inducción a lo largo de la gestación.

Cellular changes in the placenta in pregnancies complicated with diabetes / Cambios celulares en la placenta en embarazos complicados con diabetes

Placenta is the most accurate record of the infant prenatal experience. After delivery if the placenta is examined minutely, it provides much insight into the prenatal health of the baby and the mother. In diabetic pregnancy, placental weight is higher in comparison to normal pregnancy. To study the cellular differences that might contribute to larger size of placenta, light microscopic analysis was performed on 25 full term placentas, out of which 20 were of Gestational diabetes mellitus (12 controlled on diet, 8 controlled on insulin) and 5 control group. Tissue sections were processed and analyzed. Birth weight of neonate, placental weight, vascular pattern of chorionic blood vessels and site of attachment of umbilical cord were recorded. In the placenta of diabetic pregnants, gross abnormalities were uncommon but microscopic examination exhibited, to a varying degree, lesions like syncytial knots, fibrinoid necrosis, villous edema, villous fibrosis and capillary proliferation. These findings indicate that control of hyperglycemia only partially prevents the development of placental abnormalities which must be due to some other constituent factor of diabetic state.

La placenta es el registro más preciso de la experiencia prenatal infantil. Después del parto, si la placenta se examina minuciosamente, esta proporciona una visión de la salud prenatal del bebé y la madre. En el embarazo con diabetes, el peso de la placenta es mayor en comparación con el embarazo normal. Para estudiar las diferencias celulares que podrían contribuir al mayor tamaño de la placenta, se realizó el análisis en microscópico de luz en 25 placentas de término, de las cuales 20 fueron diabetes mellitus gestacional (12 controladas por dieta, 8 controlodas por insulina) y 5 del grupo control. Los cortes fueron procesados y analizados. El peso al nacer de los recién nacidos, el peso de la placenta, el patrón vascular de los vasos sanguíneos coriónicos y el lugar de inserción del cordón umbilical fueron registrados. En la placenta de las embarazadas con diabetes, alteraciones graves fueron poco frecuentes, pero el exámen microscópico mostró, en grado variable, lesiones como nudos sincisiales, necrosis fibrinoide, edema de las vellosidades, vellosidades fibrosas y proliferación capilar. Estos resultados indican que el control de la hiperglucemia sólo en parte impide el desarrollo de anormalidades de la placenta las cuales deben producirce por algún otro factor constituyente del estado diabético.

Características morfológicas y morfométricas de la placenta de término, en recién nacidos pequeños para la edad gestacional (PEG) en la ciudad de Temuco-Chile / Morphometric and morphological characteristics of the placenta at term, in small for gestational age newborns (SGA) in the city of Temuco-Chile

El metabolismo placentario, el intercambio de sustancias y la producción de hormonas son funciones vitales de la placenta para mantener y promover el desarrollo normal del feto. Existen factores de riesgo que alteran este patrón en el caso del retardo del crecimiento intrauterino, cuyo resultado será un recién nacido (RN) pequeño para la edad gestacional (PEG) que presentará una mayor morbilidad, crecimiento físico e intelectual comprometido y una mayor probabilidad de desarrollar durante la vida adulta diferentes patologías. Los objetivos del presente trabajo son: 1. Reconocer las diferencias en los parámetros morfométricos, como el área de las vellosidades, el área de los vasos, el número de vasos y el área del sinciciotrofoblasto de las placentas de PEG en relación con placentas de recién nacidos AEG y 2. Relacionar el diagnóstico neonatal de PEG con las características morfométricas. Se utilizaron 25 placentas de término (37-42 semanas), 12 de recién nacidos adecuados a la edad gestacional (AEG), y 13 de recién nacidos pequeños para la edad gestacional (PEG). Las muestras fueron obtenidas de la maternidad del Hospital Hernán Henríquez Aravena de Temuco, IX Región Chile. De cada placenta se tomaron dos segmentos pericordonales, desde la placa subcorial hasta la placa basal y luego fueron fijadas en formalina tamponada al 10 por ciento. Las técnicas histológicas utilizadas fueron H-E azul de Alcián, Tricrómico de Masson, PAS-Hematoxilina y PAS-Diastasa. El área de las vellosidades mostraron diferencias significativas entre el grupo control (AEG) y el grupo PEG con p = 0,0194. En el grupo de PEG el área de los vasos fue significativamente mayor, con un valor de 234,05 i,m² en comparación con el grupo control cuyo promedio fue de 150.99 lm² (p = 0,0001). El número de vasos sanguíneos por vellosidad libre no mostró diferencias significativas. En relación con el área del sinciciotrofoblasto la diferencia no resultó ser significativamente ...

The placental metabolism, the exchange of substances and the production of hormones are vital functions of the placenta to maintain and promote the normal development of the fetus. There are risk factors that disrupt this pattern in the case of intrauterine growth retardation, whose outcome will be a small for gestational age (SGA) newborn having a higher morbidity, physical and intellectual growth pledged and greater probability of develop different pathologies during adulthood. The aims of this study are: 1 .-recognize the morphometric parameters differences as the area of the villi, the area of the vessel, the number of vessels and the area of placental syncytiotrophoblast SGA in connection with placentas of newborns AGA and 2.- relate the diagnosis of neonatal SGA with morphometric characteristics. We used 25 placenta at term (37-42 weeks), 12 newborns appropriate to the gestational age (AEG), and 13 small for gestational age infants (SGA). The samples were obtained from the Maternity Hospital Hernán Henriquez Aravena of Temuco, Chile IX Región. In each placenta two segments were taken from the subchorionic plate to the basal plate and then were fixed in 10 percent formalin buffered. The histological techniques used were H- E Alcián blue, Masson's Trichromic, Pas-hematoxylin Pas-diastase. The area of the villi showed significant differences between the control group (AEG) and the PEG group with p = 0.0194. In the group of PEG the area of vessels was significantly higher, with a value of 234.05 mm² compared with the control group whose average was 150.99 mm² (p = 0.0001). The number of blood vessels for free villi sampling not significant differences. Regarding the area of syncytiotrophoblast the difference was not significantly (p = 0.1410). In conclusion it was determined that PEG newborns placenta showed significant differences at the blood vessel area and free chorial villi area in relation to the AEG placenta.

Microscopic examination of placenta of rats prenatally exposed to Aloe barbadensis: a preliminary study / Examen microscópico de la placenta de ratas prenatalmente expuestas a Aloe barbadensis: estudio preliminar

Aloe barbadensis is the most widely used both commercially and therapeutic properties. It has been used for an array of ailments since ancient times as a medicinal plant. There are more than 360 different species of Aloe. Its products have been used in health foods for medical and preservative purposes. The objective of this study was to search the effects of Aloe barbadensis on the rat's placenta. Gel form of Aloe barbadensis is used in the study. It is commercial, preserved but otherwise untreated form of Aloe Barbadensis gel capsul. Female Wistar Albino rats were divided into three groups. Placenta specimens from each groups were processed for the microscopic examination. Trophoblastic giant cells and spongiotrophoblasts were decreased in number after Aloe barbadensis: trophoblastic giant cells which showed degenerative changes. The nuclei of these giant cells were going degeneration characterized by pyknosis and bizarrely shaped. Extracellular matrix production around the cells was increased, thicker and more irregular basal membrane like formation around the cells. Decreased and ab normal vessel formation in labyrinth área was clear and reduced functional capacity of the trophoblastic barier. The study shows that, in the presence of Aloe barbadensis, relevant alterations associated with a possible compensatory adjustment to maintain adequate metabolic exchange take place in the structure of placenta. Our results also demonstrated that the exposure to Aloe barbadensis during pregnancy not led to fetal growth retardation, fetal death, abortion or teratogenic effect.

Aloe barbadensis es ampliamente utilizada comercialmente, debido a sus propiedades terapéuticas. Desde la antigüedad, se ha utilizado como planta medicinal para combatir una variedad de enfermedades. Hay más de 360 especies diferentes de Aloe. Sus productos han sido utilizados en los alimentos saludables para propósitos médicos y preventivos. El objetivo de este estudio fue buscar los efectos del Aloe barbadensis en la placenta de la rata. Se utilizó gel de Aloe barbadensis en el estudio. Su presentación comercial, cápsulas de gel de Aloe barbadensis de uso preventivo, no de tratamiento. Ratas Wistar albinas hembras se dividieron en tres grupos. Las placentas de cada uno de los especímenes de los grupos fueron procesadas para el examen microscópico. Las células gigantes trofoblásticas y los espongioblastos disminuyeron de número después de ser expuestas aAloe barbadensis; las células trofoblásticas gigantes mostraron cambios degenerativos. Los núcleos de estas células gigantes se caracterizaron por la degeneración, mostrando picnosis y forma extraña. La producción de matriz extracelular alrededor de las células se incrementó, hubo engrosamiento y formación de una membrana basal más irregular alrededor de las células. La disminución y formación de vasos anormales en la zona del laberinto eran evidentes y además hubo reducción de la capacidad funcional de la barrera trofoblástica. El estudio mostró que, en presencia de Aloe barbadensis, las alteraciones asociadas con un posible ajuste compensatorio paraman tener un nivel adecuado de intercambio metabólico, tienen lugar en la estructura de la placenta. Nuestros resultados también demostraron que la exposición al Aloe barbadensis durante el embarazo no produjo retraso del crecimiento fetal, muerte fetal, aborto ni efecto teratogénico.

Histological changes of human placenta in prolonged pregnancy

Prolonged pregnancy has been shown to be significantly related to increased risk of perinatal morbidity and mortality. This study aims to determine whether placentas of prolonged pregnancies have developed histological changes compared to those of term gestation and to identify these changes, if any. It also aims to test whether such changes might begin before 42 weeks of gestation and to evaluate the impact of placental histological changes in prolonged pregnancies on the perinatal outcomes. Al-Batool Teaching hospital in Mosul city in Northern Iraq, and Laboratory of Postgraduate Studies at the Department of Anatomy, Histology and Embryology in Mosul College of Medicine. This study examined placentas obtained from 220 non-hypertensive, non-diabetic, non- smoker, Rh positive singleton pregnant women who delivered in the hospital over a period of 2 months extending from Aug 1[st]. - Sep 30[th] 2005. These women were classified into three groups: Group 1; includes women who delivered between 38-41 weeks of gestation [n = 100], Group 2; includes those delivered between 41-42 weeks [n = 60] and group 3; includes women delivered beyond 42 weeks [n= 60]. Sections of group 2 and 3 placental disks showed various histological changes with different frequencies compared with those of group 1. These changes included hypovascular chorionic villi, syncytial knotting, villous stromal fibrosis, cytotrophoblastic hyperplasia, paucity of vasculosyncytial membranes, thickening of the trophoblastic basement membranes, chorionamnionitis, deciduitis, calcifications, in addition to fibromuscular sclerosis and obliterative endarteritis of the fetal stem arteries. Adverse perinatal outcomes were more frequent in group 2 and 3 compared with group 1. A dependent association was identified between adverse perinatal outcomes and several placental histological changes including cytotrophoblastic hyperplasia [p< 0.05], thickening of the trophoblastic basement membrane [p < 0.01], paucity of the vasculosyncytial membranes [VSMs] [p < 0.01], fibromuscular sclerosis [p < 0.05], and obliterative endarteritis of the fetal stem arteries [p < 0.05]. A significant proportion of prolonged pregnancy placentas has developed various histological changes in different proportions compared with those delivered at term with a clear impact on perinatal outcomes

Ultra structural of the human placenta under effect of the pre eclampsia

The human placenta is a transient organ that mediates physiological exchange between the mother and the developing fetus. It is genetically programmed for an existence of 9 months, It is important to realize that the placenta has both fetal and maternal parts and is therefore composed of cells of two different genotypes, also it focused by some diseases, the pre-eclampsia is one of them the incidence of pre eclampsia varies between 5 and 10 per cent depending on the exact definition used and the population studied, the pre-eclampsia is a major cause of morbidity and mortality in both the mother and fetus, the etiology and pathogenesis of pre-eclampsia is unknown, but reduced choriodecidual blood flow and uteroplacental ischemia is constant features, This study was performed to investigate the ultra structural changes of the placenta under effect of pre-eclampsia. Twenty full term [38-40 weeks of gestation] placentae were used in this study, 10 placentae obtained from normal females aged thirty to thirty five years old after normal vaginal delivery, the other 10 placentae obtained from females aged thirty to thirty five years old and diagnosed pre-eclampsia patient, Two samples were taken from the maternal surface and prepared to examined by the electron microscope. The structure of the placenta was affected in the patient suffering from pre-eclampsia where the nucleus of the trophoblast cells has dark chromatin with irregularity in the nuclear envelop, the cytoplasm were contained degenerative areas and irregular shaped vacuoles the mitochondrial degeneration were apparent, the fibroblast and lymphocytes infiltration were found, the wall of the villus blood vessels was thick with damage of the endothelial lining, also the microvilli on the outer surface of the syncytiotrophoblast were reduced and rudimentary

Apoptosis in normal and diabetic human placenta: light and electron microscopic study

Apoptosis, or programmed cell death, is an active process by which dysfunctional cells are eliminated to maintain normal tissue function. Apoptosis is important for normal placental development. Apoptotic cells have been identified in both the maternal and fetal compartments of the placenta during normal pregnancy. The aim of this work was to study the physiologically occurring phenomenon "apoptosis" in full term normal placentas compared with diabetic ones. Ten multipara full term pregnant women were used in this study. They were divided into two groups, control group contained five normal women, and diabetic group, contained five diabetic women treated with insulin during pregnancy. Placental specimens were obtained immediately after normal vaginal delivery and were processed for both light and electron microscopic examination. Light and electron microscopic examination of normal specimens showed the normal structure of chorionic villi of full term placenta. Apoptotic cells were detected normally in all layers of placental villi. Light microscopic examination, of the diabetic placental specimens showed many degenerated chorionic villi. Its, syncytiotrophoblastic covering was thin, degenerated and necrotic. Syncytial knots were more frequently observed. Collagen fibers were increased in stroma of the degenerated villi. Fetal capillaries were dilated, congested and lined by degenerated endothelial cells. Apoptotic cells appeared more numerous in all layers of diabetic placental villi compared to controls. Electron microscopic examination of diabetic placental villi revealed destruction of syncytial microvilli. Syncytial cytoplasm was markedly vacuolated. Trophoblastic basement membrane was irregularly thickened. Marked increase of collagen fibers was observed in the villous stroma. Fetal capillaries were extremely dilated and were lined by degenerated endothelial cells. Apoptotic cells were more frequently seen in all layers of placental villi compared to normal ones. In conclusion, apoptosis occurred physiologically in normal placenta and increased dramatically in diabetic placenta

Anatomical aspects of the placenta of the sloth, Bradypus variegatus, Schinz, 1825

Sloth plows euterians mammals, belonging to the order Edentata, sub-order Xenarthra, infra-order Tardigrada, family Bradipodidae, which comprehend three specimen, Bradypus tridadctylus, Bradypus variegates and Bradypus torquatus. They plows few work found in the literature related to the anatomy of the placenta of this specimen. The material used in this research was consisted of 3 placentas of Bradypus variegatus of adult females (Briton, 1941) original of the Forests of the City of Recife and Zone of the Forest of the State of Pernambuco with average weight 4,2 Kg. Placentas were fixed in buffered glutaraldehyed 4 per cent, pH 7,4, 0,1M and processed goes optical microscopy. Macroscopically was observed that the placenta of the sloth is composed of discoidal lobes and had the fundal position of the uterine cavity. The fetal membranes identified were chorium, applied on the uterine surface and, amnion adherent to inner face of chorium. In the specimen examined presented vestige of allantois sack and vitelline sack in these gestational phase. Anatomically, placenta of Bradypus variegatus could be classified like chorium-amniotic. Microscopic analysis of the placenta showed endothelial cells of maternal vessel hypertrophied and fetal components without cellular limits identified. The fetal tissue presented an epithelioid aspect with fetal vessel surrounded to connective tissue and epithelioid cells or next to maternal vessel. According our description, Placenta of Bradypus variegatus could be classified microscopically in syndesmochorial and endotheliochorial

Effect of smoking on the human placenta morphological and ultrastructural study

Smoking is one of the most harmful habits facing the community. Smoking causes major health problems especially in pregnant women because it is one of the causes of premature labour and low birth weight. The hazards of smoking either to the fetus or to the placenta are due to its effect on the blood vessels of the placenta. Under electron microscope the placenta of the smoking women showed vaccuolation and thick basement membrane of the trophoblast, increase in synthetical knob and also decrease in the number of microvilli of the synthetiotrophoblast. The aim of this study was to prove that smoking during pregnancy has an adverse effect on the placenta and baby and to advice pregnant women to avoid smoking during pregnancy whether active or passive

histological study of human placental villi at different gestational ages by scanning electron microscopy

Five specimens were taken from normal full-term placentae immediately after delivery and other five were obtained from placentae at 10-14 weeks of gestation after therapeutic abortion. All specimens obtained were immersed in 4% glutaraldehyde in phosphate buffer and prepared to be examined by scanning electron microscopy. The study concluded that human placental villi was designed in a highly specialized pattern to allow a maximum absorptive capacity per surface area. This was achieved by a complete covering of villi by numerous microvilli, furrows in the villi to increase its surface area and an increased number of microvilli with age to face demands of growing fetus. Normal healthy placentae had no areas devoid of microvilli on the chorionic villous surface. The presence of such areas may be due to pathological conditions and most probably related to fetal biology and may have deleterious effect on the growing fetus

Análise morfológica da placenta da paca (Agouti paca, Linnaeus, 1766: Estudo ao microscópio de luz e à microscopia eletrônica de transmissäo / Morphological analysis of the placenta of paca (Agouti paca L., 1766): Study with light microscopy and transmission electron microscopy

Foram estudados os aspectos morfológicos de nove placentas de paca (Agouti paca, L., 1766) mediante análises em microscopia de luz e eletrônica de transmissäo dos fragmentos teciduais correspondentes à porçäo de maior conexäo placentária em diferentes fêmeas gestantes, nos estágios intermediário e final da prenhez. Realizamos este estudo, pois, aliada à necessidade da procura de novas espécies que atuem como modelos experimentais adequados, havia a disponibilidade deste roedor em nosso meio; por outro lado, o melhor conhecimento dos aspectos reprodutivos destes animais oferece subsídios ao estabelecimento de criatórios racionais desta espécie, uma vez que a preservaçäo deste vertebrado é necessária, além do grande interesse comercial em torno de sua carne. Os resultados mostraram que este roedor possui uma placenta do tipo vitelina e outra do tipo corioalantoidiana, sendo este órgäo do tipo hemocorial, labiríntico, que se apresenta histologicamente composto por lóbulos divididos em três regiöes distintas: o centro do lóbulo, o labirinto e o interlóbulo. Na regiäo do centro do lóbulo, verificou-se a presença de artérias e veias; e em sua regiäo periférica estavam presentes dois sistemas tubulares arranjados de forma paralela, onde as lacunas sangüíneas e os capilares estavam em íntimo contato, formando a regiäo do labirinto. O interlóbulo era composto de artérias e veias. O trofoblasto era o principal componente da placenta, que, independentemente da regiäo onde se encontrava, mostrava-se de natureza sincicial. Ultra-estruturalmente a barreira placentária da paca foi classificada como hemomonocorial

Apoptosis en trofoblasto de pacientes con aborto espontáneo recurrente de causa no identificada / Apoptosis in trophoblast of patients with recurrent spontaneous abortion of non identified cause

El aborto espontáneo recurrente de causa no identificada o idiopático es un importante problema de salud reproductiva. En este trabajo se ha iniciado el estudio de uno de los mecanismos que podrían mediar en esta patología del embarazo humano, La hipótesis general que se propone, es que en los casos de pacientes con aborto espontáneo recurrente de causa no identificada (AER), existen fenómenos en el entorno materno/feto/placentario que se manifiestan en daño en la funcionalidad y/o vitalidad del tejido placentario. La hipótesis planteada fue consistente con el hallazgo de activación masiva de muerte celular programada en todos los casos con AER estudiados en este trabajo.

Ultrastructure of the villous fibrinoid in the human full-term placenta

El material fibrinoide de las vellosidades coriales humanas ha sido estudiado con el microscopio electrónico. Fueron identificados cuatro constituyentes en la substancia fibrinoide: una matriz homogénea, amorfa; microfilamentos, restos celulares y corpúsculos calcificados. Los microfilamentos no presentan periodicidad, son muy abundantes y se disponen irregularmente. Los restos celulares derivan, probablemente, del sinciciotrofoblasto degenerado, mientras que los corpúsculos calcificados son semejantes a los corpúsculos de Michaelis-Gutmann. Los resultados obtenidos sugieren que el material fibrinoide deriva tanto de la degeneración del sinciciotrofoblasto como de la síntesis por las células de Langhans residuales y las células X