Microbial exposure during early human development primes fetal immune cells.

The human fetal immune system begins to develop early during gestation; however, factors responsible for fetal immune-priming remain elusive. We explored potential exposure to microbial agents in utero and their contribution toward activation of memory T cells in fetal tissues. We profiled microbes across fetal organs using 16S rRNA gene sequencing and detected low but consistent microbial signal in fetal gut, skin, placenta, and lungs in the 2nd trimester of gestation. We identified several live bacterial strains including Staphylococcus and Lactobacillus in fetal tissues, which induced in vitro activation of memory T cells in fetal mesenteric lymph node, supporting the role of microbial exposure in fetal immune-priming. Finally, using SEM and RNA-ISH, we visualized discrete localization of bacteria-like structures and eubacterial-RNA within 14th weeks fetal gut lumen. These findings indicate selective presence of live microbes in fetal organs during the 2nd trimester of gestation and have broader implications toward the establishment of immune competency and priming before birth.

Prenatal diagnosis of 913 fetuses samples using copy number variation sequencing.

BACKGROUND: The present study aimed to explore the etiological relationship between fetal abnormalities and copy number variations (CNVs) with the aim of intervening and preventing the birth of children with birth defects in time. METHODS: Samples of 913 fetuses with puncture indications were collected from January 2017 to December 2019. Karyotype analysis and CNV sequencing (CNV-seq) testing was performed for fetuses with ultrasonic abnormalities, a high risk of Down's syndrome and an adverse birth history. All cases were followed up. RESULTS: In total, 123 cases (13.47%) had abnormal karyotypes, including 109 cases with chromosome number abnormalities and 14 cases of chromosomal structural abnormalities. Thirty-seven (4.05%) cases with pathogenic CNVs were detected. The detection rate of pathogenicity CNVs was 12.82% for mixed indications, followed by 7.5% for an adverse birth history, 5.88% at high risk of non-invasive prenatal testing, 5.00% with an abnormal ultrasonic marker, 1.89% at high risk of screening for Down's syndrome and 1.45% with advanced maternal age. There were 12 (1.31%) cases with microduplications and 25 (2.74%) cases with microdeletions. Trisomy 21 (39.02%), trisomy 18 (13.82%) and Turner syndrome (9.76%) were the top three chromosome abnormalities. There were 104, 746 and 63 cases in the 11-13 weeks, 14-27 weeks 28-38 weeks gestational ages, respectively. The abnormal rates of fetal chromosome aneuploidy and the rate of pathogenic CNVs were decreased and increased with the increase of gestational age (p < 0.05), respectively. CONCLUSIONS: Compared with karyotype analysis, CNV-seq can improve the detection rate of chromosomal abnormalities. CNV-seq combined karyotype analysis should be performed simultaneously in fetuses with puncture indications.

Viable bacterial colonization is highly limited in the human intestine in utero.

Mucosal immunity develops in the human fetal intestine by 11-14 weeks of gestation, yet whether viable microbes exist in utero and interact with the intestinal immune system is unknown. Bacteria-like morphology was identified in pockets of human fetal meconium at mid-gestation by scanning electron microscopy (n = 4), and a sparse bacterial signal was detected by 16S rRNA sequencing (n = 40 of 50) compared to environmental controls (n = 87). Eighteen taxa were enriched in fetal meconium, with Micrococcaceae (n = 9) and Lactobacillus (n = 6) the most abundant. Fetal intestines dominated by Micrococcaceae exhibited distinct patterns of T cell composition and epithelial transcription. Fetal Micrococcus luteus, isolated only in the presence of monocytes, grew on placental hormones, remained viable within antigen presenting cells, limited inflammation ex vivo and possessed genomic features linked with survival in the fetus. Thus, viable bacteria are highly limited in the fetal intestine at mid-gestation, although strains with immunomodulatory capacity are detected in subsets of specimens.

Optimization of Pulmonary Vasculature Tridimensional Phenotyping in The Rat Fetus.

Comparative, functional, developmental, and some morphological studies on animal anatomy require accurate visualization of three-dimensional structures. Nowadays, several widely applicable methods exist for non-destructive whole-mount imaging of animal tissues. The purpose of this study was to optimize specimen preparation and develop a method for quantitative analysis of the total pulmonary vasculature in fetal rats. Tissues were harvested at E21 and fetuses fixed overnight in 4% paraformaldehyde/phosphate buffered saline. They were treated with 25% Lugol solution for 72 hours to ensure perfusion. Four different methods were used for fetal specimen preparation; isolated lung, upper torso, direct right ventricle contrast injection, and whole body with partial thoracic skin excision. The microCT scan was performed, and pulmonary vasculature was segmented. Vessels were analyzed for diameter, length, and branching. Of the four preparation methods, only whole body with partial thoracic skin excision resulted in adequate reconstruction of the pulmonary vasculature. In silico generated 3D images gathered by micro CT showed pulmonary vasculature distributed throughout the lung, which was representative of the shape and structure of the lungs. The mean number of vessels segmented in the pulmonary tree was 900 ± 24 with a mean diameter of 134.13 µm (range 40.72-265.69 µm). While up to the 30th generation of vessels could be segmented, both for arteries and veins, the majority of branching was between the 21st and 30th generations. Passive diffusion of contrast material enables quantitative analysis of the fetal pulmonary vasculature. This technique is a useful tool to analyze the characteristics and quantify the fetal pulmonary vasculature.

Evolutionary implications of fetal and maternal microvillous surfaces in epitheliochorial placentae.

According to the "parent-offspring conflict hypothesis" the rapid evolution and diversification of the mammalian placenta is driven by divergent optima of resource allocation between fetus and mother. The fetus has an interest to maximize its resource intake, while the mother has an interest to restrict the transfer of resources, and thus retain resources for subsequent pregnancies. In the epitheliochorial placenta, the contacting fetal and maternal surfaces at the feto-maternal interface are covered with microvilli, which leads to an increase of membrane surfaces available for transport processes. Because membranes are the site of active transport, the conflict hypothesis predicts that the fetal surfaces at the feto-maternal interfaces are larger than the maternal ones. We use transmission electron microscopy and a stereological method to estimate the factors by which the apical fetal and maternal membranes are enlarged by the microvilli. Ten species with an epitheliochorial placenta were studied. Focused ion beam-scanning electron microscopy (FIB-SEM) was used to create three-dimensional models of the interdigitating microvilli of the bovine and porcine placenta. In all species, the fetal surface was larger than the maternal. This was due to a higher number of fetal microvilli and to the presence of membrane folds at the base of the fetal, but not of maternal microvilli. Our results suggest that the ultrastructural morphology of the feto-maternal interface in the epitheliochorial placenta is shaped by conflicting interests between fetus and mother and thus represent a so far neglected arena of the parent-offspring conflict.

The Kyoto Collection of Human Embryos and Fetuses: History and Recent Advancements in Modern Methods.

The Kyoto Collection of Human Embryos and Fetuses, the largest collection of human embryos worldwide, was initiated in the 1960s, and the Congenital Anomaly Research Center of Kyoto University was established in 1975 for long-term storage of the collection and for the promotion of research into human embryonic and fetal development. Currently, the Kyoto Collection comprises approximately 45,000 specimens of human embryonic or fetal development and is renowned for the following unique characteristics: (1) the collection is considered to represent the total population of fetal specimens nationwide in Japan, (2) it comprises a large number of specimens with a variety of external malformations, and (3) for most specimens there are clinical and epidemiological data from the mothers and the pregnancies concerned. Therefore, the specimens have been used extensively for morphological studies and could potentially be used for epidemiological analysis. Recently, several new approaches such as DNA extraction from formalin-fixed specimens or geometric morphometrics have been adopted and it is to be expected that further technological advances will facilitate new studies on the specimens of the Kyoto Collection as well as of other human embryo collections worldwide. Permanent preservation of the Kyoto Collection is, therefore, of paramount importance so that it will continue to contribute to human embryological studies in the future.

Ultramorphological Characteristics of Podocyte Development in the Human Fetal Metanephros.

The aim of this study was to determine the developmental characteristics of podocytes in the human fetal metanephros using scanning electron microscopy, light microscopy, and transmission electron microscopy. Kidney samples of 15 human fetuses of both sexes (gestational age 10-22 weeks) were analyzed. At the S-shaped body stage, primitive podocytes were arranged in a layer of cuboidal cells beneath the vascular cleft. When observed from Bowman's space, the demarcation between adjacent podocytes was not clear, but mild depressions indicated cell boundaries. At the more advanced S-shaped body stage, podocytes were polygonal, with a flat apical surface. They were in close contact, but boundaries between adjacent cells were distinct. After initial separation of their apical parts, podocytes continued to separate from each other along their lateral sides. Their shape changed from polygonal to spherical, resembling clusters of grapes. Cytoplasmic buds could be seen at the base of some podocytes initially, when all podocytes were spherical. Parallel with the development of the first capillary loops, wider intercellular spaces were noted between elliptical-shaped podocytes. Podocytes then developed cytoplasmic processes and became flattened and star shaped. Their cell bodies separated from the glomerular basement membrane through the insertion of thick processes under the cell body. Thick primary processes ramified to form the foot processes, which interdigitated on the surface of capillary loops. During the capillary loop stage, the degree of differentiation of the podocytes varied among various glomerular regions, as well as within the same capillary loop.

Effects of Hydroxyurea Exposure on the Rat Cerebellar Neuroepithelium: an Immunohistochemical and Electron Microscopic Study Along the Anteroposterior and Mediolateral Axes.

We present a histological study of the cell death of cerebellar neuroepithelial neuroblasts following treatment with the cytotoxic agent hydroxyurea (HU) during the embryonic life. Pregnant rats were treated with a single dose of HU (300 mg/kg) at embryonic days 13, 14, or 15 of gestation, and their fetuses were studied from 5 to 35 h after treatment to elucidate the mechanisms of HU-induced fetotoxicity. Quantification of several parameters such as the density of pyknotic, mitotic, and PCNA-immunoreactive cells indicated that HU compromises the survival of the cerebellar neuroepithelium neuroblasts. On the other hand, our light and electron microscopic investigations during the course of prenatal development indicated that HU leads to two types of cell death: apoptosis and cells presenting cytoplasmic vacuolization, altered organelles, and a recognizable cell nucleus. Both modalities of cell death resulted in a substantial loss of cerebellar neuroepithelium cells. Current results suggest that HU exposure during gestation is toxic to the cerebellar neuroepithelium. Moreover, they allow to examine the mechanisms of HU-induced toxicity during the early development of the central nervous system. Our data also suggest that it is essential to avoid underestimating the adverse effects of HU when administered during early prenatal life.

Functional and structural microanatomy of the fetal sciatic nerve.

INTRODUCTION: The ultrastructure of a nerve has implications for surgical nerve repair. The aim of our study was to characterize the fascicular versus fibrillar anatomy and the autonomic versus somatic nature of the fetal sciatic nerve (SN). METHODS: Immunohistochemistry for vesicular acetylcholine transporter, tyrosine hydroxylase, and peripheral myelin protein 22 was performed to identify cholinergic, adrenergic, and somatic axons, respectively, in the human fetal SN. Two-dimensional (2D) analysis and 3D reconstructions were performed. RESULTS: The fetal SN is composed of one-third stromal tissue and two-thirds neural tissue. Autonomic fibers are predominant over somatic fibers within the neural tissue. The distribution of somatic fibers is initially random, but then become topographically organized after intra- and interfascicular rearrangements have occurred within the nerve. CONCLUSIONS: The fetal model presents limitations but enables illustration of the nature of the nerve fibers and the 3D fascicular anatomy of the SN. Muscle Nerve 56: 787-796, 2017.

Molecular genotyping of placental site and epithelioid trophoblastic tumours; female predominance.

OBJECTIVE: To investigate a large series of placental site trophoblastic tumours (PSTT) and epithelioid trophoblastic tumours (ETT) and determine the relationship between their development and the type and sex of both the immediately antecedent and causative pregnancies. METHODS: The antecedent pregnancy was determined from patient records in 92 cases with a confirmed diagnosis of PSTT, ETT or mixed PSTT/ETT. In a subset of 57 cases, type and sex of the causative pregnancy was established by molecular genotyping of tumour tissue microdissected from formalin-fixed, paraffin-embedded blocks. RESULTS: The antecedent pregnancy was a normal live birth in 59 (64%) cases, a hydatidiform mole in 19 (21%) and other pregnancy loss in 14 (15%). Where the sex was recorded, 36 (78%) of 46 antecedent normal pregnancies were female, a significantly greater proportion than expected (p<0.0001). Genotyping of 57 cases found 15 (26%) to derive from hydatidiform moles while 42 (74%) arose in non-molar pregnancies. Where the causative pregnancy was non-molar, 38 (91%) tumours arose in female conceptions, significantly greater than expected (p<0.0001). Analysis of short tandem repeats on the X chromosome in three tumours with an XY chromosomal constitution confirmed that the X chromosome was maternal in origin. CONCLUSIONS: PSTT and ETT predominantly arise in female pregnancies but can develop in male pregnancies. A male derived X chromosome is not required for the development of these tumours. While these tumours are predominantly female it is not because most originate in complete hydatidiform moles.

Characterization of paneth cells in alpacas (Vicugna pacos, Mammalia, Camelidae).

Paneth cells are secretory epithelial cells of the innate immune system of the intestine of several mammals, including alpacas. Little is known about the latter; thus, in the present study we described the morphology and histochemical characteristics of Paneth cells in healthy fetuses, and young and adult alpacas. For this purpose, samples of duodenum, jejunum and ileum were taken from 6 fetuses at different days of pregnancy (between days 221-330), 66 offsprings (between 0 and 45-days-old) and 5 adult alpacas (>2-years-old). Samples were fixed in 10% buffered formalin and processed for histological and morphometrical analysis using HE and Masson Trichomics technique. Immunohistochemistry was used to identify Paneth cells using anti-lysozyme antibody. In addition, the lectinhistochemichal binding-pattern of Paneth cells granules was evaluated. Lyzozyme was immunohistochemically detected in the granules of Paneth cells from day 283 of pregnancy in all the small intestinal sections of the studied fetuses. In newborn alpacas Paneth cells were initially found in the duodenum, but the following days (days 18-21 after birth) they were also found in the ileum. Their size gradually increased after birth, but then no significant differences were found. In adult alpacas the number was lower than offsprings. We suggest that Paneth cells early differentiate in the small intestine of alpacas, and the increase in their number during the first two weeks of life strongly support their possible involvement in the intestinal defensive functions against the enteric diseases that occur during the lactancy stage.

[Topography, relations and transformation of lumbar lymphatic sacs].

The peculiarities of the structure, skeletotopy, and syntopy of the lumbar lymphatic collector were studied on 20 5-8 week-old embryos and on 80 9-36 week-old fetuses using a complex macro-microscopic method. It is found that the lumbar lymphatic collector in fetuses at 9-10 weeks was represented by retroperitoneal and retroaortic lymphatic sacs that had a fusion mode of formation and were interconnected. Retroperitoneal sac was located in the projection of L(I)-L(IV) and was in contact with the anterior surface of the abdominal aorta and inferior vena cava, aortic lumbar paraganglia, abdominal aortic plexus and ganglia of sympathetic trunk. Retroaortic sack at L(I)-L(II) was adjacent to posterior surface of the aorta, the lumbar vertebrae and the medial crus of the diaphragm. These topical relations were preserved throughout the whole fetal period. However, in fetuses of 11-13 weeks lymphatic sacs formed the lymphatic plexuses, while in fetuses of 14-36 weeks they formed lumbar lymph nodes and their interconnecting vessels.

Foetal dilated cardiomyopathy with left ventricular thrombosis.

Serial foetal echocardiography showed the development of severe left ventricular systolic dysfunction and thrombosis in a previously healthy foetus. Normal cardiac findings in a mid-trimester foetus do not exclude subsequent dilated cardiomyopathy.

Diagnostic accuracy of fundal height and handheld ultrasound-measured abdominal circumference to screen for fetal growth abnormalities.

OBJECTIVE: We sought to compare fundal height and handheld ultrasound-measured fetal abdominal circumference (HHAC) for the prediction of fetal growth restriction (FGR) or large for gestational age. STUDY DESIGN: This was a diagnostic accuracy study in nonanomalous singleton pregnancies between 24 and 40 weeks' gestation. Patients underwent HHAC and fundal height measurement prior to formal growth ultrasound. FGR was defined as estimated fetal weight less than 10%, whereas large for gestational age was defined as estimated fetal weight greater than 90%. Sensitivity and specificity were calculated and compared using methods described elsewhere. RESULTS: There were 251 patients included in this study. HHAC had superior sensitivity and specificity for the detection of FGR (sensitivity, 100% vs 42.86%) and (specificity, 92.62% vs 85.24%). HHAC had higher specificity but lower sensitivity when screening for LGA (specificity, 85.66% vs 66.39%) and (sensitivity, 57.14% vs 71.43%). CONCLUSION: HHAC could prove to be a valuable screening tool in the detection of FGR. Further studies are needed in a larger population.

[The mother-placenta-fetus system in diffuse toxic goiter: Morphopathological aspects].

OBJECTIVE: to compare the clinical and morphological parallels of the mother-placenta-fetus system in diffuse toxic goiter (DTG) through current morphological examinations. SUBJECTS AND METHODS: Sixty-five women whose pregnancy occurred with DTG were examined using both clinical and morphological studies (light, scanning electron, and atomic-force microscopies and macro- and microelement analysis); the placenta and uterus were investigated. RESULTS: Destructive changes and microrelief impairment, resulting from circulatory disorders (ischemia) and hemic hypoxia, were observed in the presence of DTG during pregnancy. Abnormal placental immaturity developed; the number of terminal villi decreased; sclerosis occurred. The magnitude of changes showed up to a greater extent in the myometrium, umbilical cord, and placenta of women, whose pregnancy occurred with DTG, and in patients with disease recurrence. In preeclampsia, plethora, stasis, and thrombosis were added to circulatory disorders. CONCLUSION: Not only the diagnosis itself of DTG, but also the type of its course and the pattern of obstetric disease, primarily preeclampsia, affect the state of structural components of the uteroplacental unit.

Human fetal ductal plate revisited. I. ductal plate expresses NCAM, KIT, MET, PDGFRA, and neuroendocrine antigens (NSE, chromogranin, synaptophysin, and CD56).

BACKGROUND: The molecular mechanisms of ductal plate (DP) development and differentiation (DD) in human fetal livers (HFLs) are unclear. MATERIALS AND METHODS: The author immunohistochemically investigated expressions of NCAM, KIT, KIT, PDGFRA, and neuroendocrine antigens in 32 HFLs. RESULTS: The processes of human intrahepatic bile duct (IBD) DD could be categorized into four stages: DP, remodeling DP, remodeled DP, and mature IBD. NCAM was always expressed in DP and remodeling DP, but not in remodeled DP and mature IBD. The biliary elements were positive for cytokeratin (CK)7, 8, 18, and 19. The hepatoblasts were positive for CK8 and CD18, but negative for CK7 and CK19; however, periportal hepatoblasts showed biliary-type CKs (CK7 and CK19). NCAM was always expressed in DP and remodeling DP, but not in remodeled DP and mature IBD. KIT was occasionally (12/32 cases) expressed in DP and remodeling DP, but not in remodeled DP and mature IBD. NCAM expression was also seen in some hepatoblasts and hematopoietic cells and neurons. KIT was also expressed in some hepatoblasts, hematopoietic cells, and mast cells. MET and PDGFRA were strongly expressed in DP, remodeling DP, remodeled DP, and mature IBD. MET and PDGFRA were also strongly expressed in hepatoblasts and hematopoietic cells. MET and PDGFRA were not expressed in portal mesenchyme, portal veins, sinusoids, and hepatic veins. DP showed immunoreactive chromogranin, synaptophysin, neuron-specific enolase (NSE), and CD56. Expressions of chromogranin and CD56 were infrequently seen in remodeling DP. No expressions of these four neuroendocrine antigens were seen in remodeled DP and mature IBD. The nerve fibers were consistently positive for chromogranin, synaptophysin, NSE, and CD56 in the portal mesenchyme in the stages of remodeling DP, remodeled DP, and mature IBDs. CONCLUSIONS: The data suggest that NCAM, KIT/stem cell factor-signaling, NSE, hepatocyte growth factor/MET signaling, PDGFα/PDGFRA signaling, chromogranin, synaptophysin, and CD56 play important roles in DD of biliary cells of HFL. They also suggest that the DP cells having neuroendocrine molecules give rise to hepatic stem/progenitor cells.

Development of extrahepatic bile duct excluding gall bladder in human fetuses: histological, histochemical, and immunohistochemical analysis.

BACKGROUND: The fetal development of extrahepatic bile ducts (EBD) is unkown. MATERIALS AND METHODS: Development of EBD was examined by immunohistochemistry in 16 fetuses of 7-40 gestational week (GW). Gall bladder (GB) was not investigated. RESULTS: At seven GW, a hepato-pancreatic bud (HPB) was seen near the hepatic hilus. At eight GW, embryonic EBD, GB and pacreas developed from HPB. Portal veins (PV) and hepatic arteries (HAs) were present in EBD at eight GW. Liver parenchyma was already present in seven GW. At eight GW, EBD at porta hepatis (PH) was already established; PH EBD was derived from ductal plate (DP). The distal and middle EBD gradually develeped and took shape of EBD at nine GW. In PH, cystic and hepatic ducts developed from DP at eight GW. EBD developed further, accompanying many nerve fibers (NF) at PH and distal and middle EBD. Apparent PV and HA were seen around 12 GW. Around 20 GW, HA and capillaries proliferated, giving rise to peribiliary capillary plexus (PCP) in all parts of EBD. EBD grew gradually further, and around 30 GW extrahepatic peribiliary glands (EPG) emerged from EBD but not from cystic duct. Around 36 GW, exocrine pancreatic acinar cells emerged from remodeled DP at PH. At term (40 GW), EBD was established but was as yet immature. Numerous NF were present around EBD. Histochemically, EBD epithelium had no mucins at 7-12 GW but contained neutral and acidic mucins at 23-40 GW. EPG had abundant neutral and acidic mucins. Immunohistochemically, alpha-fetoprotein (AFP) was consistently positive in the epithelial and mesenychyma. The NF and muscles of HPB present at seven GW were positive for neural cell adhesion molecule (NCAM), neuron-specific enolase (NSE), platelet-derived growth factor receptor-α (PDGFRA), and KIT, but they disappeared in nine GW. Expressions of cytokeratin (CK) seven and CK19 in EBD and EPG were slight or none, while expression of CK8 was moderate, and that of CK18 was strong. NF were positive for NCAM, NSE, synaptophysin, and chromogranin, and PDGFRA. MUC1 and MUC6 apomucins were noted in EBD and EPG. EPG contained numerous endocrine cells positive for chromogranin, synaptophysin, NCAM and NSE. A few endocrine cells positive for these antigens were seen in EBD. Numeous KIT-positive stem cells (SC) were seen in PH, EBD, PV, HA, PCP, and EPG. NCAM-positive and bcl-2-positive SC were also located in these structures. Epithelial cells of EBD and EPG showed expressions of MET, PDGFRA, CA19-9, MUC1, MUC2, MUC6, KIT, bcl-2, and ErbB2. No expressions of HepPar1, carcinoembryonic antigen (CEA), and epithelial membrane antigen (EMA) were noted. CONCLUSIONS: Although the findings have limitatios because this study of humans are descriptive one, the present data suggest that the processes of the development and differentiation of EBD system may be associated with EBD SC, CK prolifes, SFC/KIT signaling, HGF/MET signaling, PDGRa/PDGFRA signaling, fibroblast growth factor/ErbB2 signaling, neuroendocrine lineage, NF differentiation, pancreatic aninar cell differentiation, PCP differentiation, MUC apomucins differentiation, and expressions of AFP and CA19-9. HepPar1, EMA and CEA were not involved in them.

Study of the ureter structure in anencephalic fetuses

Purpose The objective of this paper is to analyze the structure of the ureter in normal and anencephalic human fetuses. Materials and Methods We studied 16 ureters from 8 human fetuses without congenital anomalies aged 16 to 27 weeks post-conception (WPC) and 14 ureters from 7 anencephalic fetuses aged 19 to 33 WPC. The ureters were dissected and embedded in paraffin, from which 5 µm thick sections were obtained and stained with Masson trichrome, to quantify smooth muscle cells (SMC) and to determine the ureteral lumen area, thickness and ureteral diameter. The samples were also stained with Weigert Resorcin Fucsin (to study elastic fibers) and Picro-Sirius Red with polarization and immunohistochemistry analysis of the collagen type III fibers to study collagen. Stereological analysis of collagen, elastic system fibers and SMC were performed on the sections. Data were expressed as volumetric density (Vv-%). The images were captured with an Olympus BX51 microscope and Olympus DP70 camera. The stereological analysis was done using the Image Pro and Image J programs. For biochemical analysis, samples were fixed in acetone, and collagen concentrations were expressed as micrograms of hydroxyproline per mg of dry tissue. Means were statistically compared using the unpaired t-test (p < 0.05). Results The ureteral epithelium was well preserved in the anencephalic and control groups. We did not observe differences in the transitional epithelium in the anencephalic and control groups. There was no difference in elastic fibers and total collagen distribution in normal and anencephalic fetuses. SMC concentration did not differ significantly (p = 0.1215) in the anencephalic and control group. The ureteral lumen area (p = 0.0047), diameter (p = 0.0024) and thickness (p = 0.0144) were significantly smaller in anencephalic fetuses. Conclusions Fetuses with anencephaly showed smaller diameter, area and thickness. These differences could indicate ...

Neuroprotective effect of magnesium sulfate and dexamethasone on intrauterine ischemia in the fetal rat brain: ultrastructural evaluation.

AIM: The aim of this study was to investigate the neuroprotective effect of magnesium sulfate and dexamethasone on oxidative damage in intrauterine ischemia. MATERIAL AND METHODS: In this study, 19-day pregnant rats were divided into five groups. Fetal brain ischemia was achieved in the ischemia/ reperfusion (I/R) group by bilaterally closing the utero-ovarian artery with aneurysm clips for 30 min and subsequently removing the aneurysm clips for 60 min for reperfusion. Mg (600 mg/kg) and dexamethasone (0.25 mg/kg) were administered 20 min before the I/R insult. The lipid peroxidation in the brain tissue was determined by the concentration of thiobarbituric acid reactive substances (TBARS). The mitochondrial score was calculated after an evaluation with electron microscopy. RESULTS: Both the electron microscope and TBARS data showed a significant difference between the control and I/R groups. The Mg and dexamethasone treatment groups exhibited significantly lower TBARS values compared to the IR group. Similarly, the mitochondrial scores in the Mg and dexamethasone treatment groups were significantly lower than those in the I/R group. CONCLUSION: Result showed that magnesium sulfate and dexamethasone prevent lipid peroxidation and reduce mitochondrial injury thus suggests neuroprotective effects in fetal rat brain in intrauterine ischemia-reperfusion (I/R) injury.

Histomorphometric and immunohistochemical study of the goat reticulum during prenatal development.

This study sought to describe the morphological changes taking place in the goat reticulum during prenatal development, using histomorphometric and immunohistochemical techniques. A total of 140 goat embryos and foetuses were used, from the first stages of prenatal life until birth. Differentiation of the reticulum as a separate compartment of the primitive gastric tube was observed at 35 days of prenatal life (23% gestation). By 38 days (25% gestation) the reticular wall comprised three layers: an internal epithelial layer, a middle layer of pluripotential blastemic tissue and an external layer or serosa. Primary reticular crests were visible at 59 days (38% gestation) as evaginations of the epithelial stratum basale, marking the earliest histological differentiation of future reticular cells. Secondary reticular crests were observed at 87 days (61% gestation). Corneum papillae first became apparent on the lateral surface of primary reticular crests at 101 days (64% gestation). The muscularis mucosae was visible by 101 days (64% gestation) in primary reticular crests. Neuroendocrine cells were detected by synaptophysin at 64 days (43% gestation), while glial cell markers (glial fibrillary acidic protein and vimentin) were observed at 64 days (43% gestation) and 38 days (25% gestation), respectively. The peptidergic innervation markers such as neuropeptide Y and vasoactive intestinal polypeptide were detected at 75 days (50% gestation). In conclusion, prenatal development of the reticulum - like that of the rumen - appears to take place somewhat earlier in goats than in sheep or cattle, but at a similar rate to that reported in deer.