The Development of the Embryo and Membranes of the Humpback Whale, Megaptera nodosa (Bonnaterre)

1960 ◽  
Vol 11 (3) ◽  
pp. 365 ◽  
Author(s):  
CW Stump ◽  
JP Robins ◽  
ML Garde
Keyword(s):  
Umbilical Cord ◽  
Uterine Cavity ◽  
Distal Region ◽  
Yolk Sac ◽  
Consecutive Series ◽  
Chorionic Villi ◽  
Suspensory Ligament ◽  
Foetal Membranes ◽  
Uterine Fluid ◽  
Tubular Form

The material consists of 20 embryos (5-30 mm) and two foetuses (63 mm and 90 mm) collected at whaling stations on Moreton and Norfolk Islands (latitude 27� 11'S. and 29� 5' S. respectively) during late August, September, and early October in 1952-53-54 and 1956. The consecutive series permitted the study of membrane formation and organogenesis. Younger embryos are found in grooves between the folds of endometrium in a constant site in that uterine horn associated with the ovary containing the recent corpus luteum. Older embryos and the early foetus are adapted to lie freely in the uterine fluid, and are devoid of any mechanism for apposition or attachment to the endometrium. Variation in the sequence of the association of the components of the umbilical cord provides suspensory structures for the amnion and yolk sac, and for the embryo a bifid ligament, retained in the early foetus for attachment of the foetal membranes. In the younger foetus the allantoic duct drains the nephric secretion into the uterine cavity. In the older foetus chorionic villi are present. The bifid suspensory ligament forms the major part of the distal region of the umbilical cord. The allantoic duct is reunited with the allantoic sac. Amniogenesis is by folding. During the embryonic period the chorio-amniotic connection forms a suspensory ligament. The yolk sac, attached by a novel ligament to the amnion, is large and functional in the embryo. In the foetus vascular splanchnopleure is present in a tubular form. A rete system develops in the embryo.

Three-Dimensional Sonographic Evaluation of the Position of the Fetal Conus Medullaris at First Trimester

2021 ◽  
pp. 1-8
Author(s):  
Ruben Ramirez Zegarra ◽  
Nicola Volpe ◽  
Evelina Bertelli ◽  
Greta Michela Amorelli ◽  
Luigi Ferraro ◽  
...  
Keyword(s):  
Abdominal Wall ◽  
Umbilical Cord ◽  
Interobserver Agreement ◽  
Interobserver Variability ◽  
First Trimester ◽  
3D Ultrasound ◽  
Conus Medullaris ◽  
Consecutive Series ◽  
Fetal Life ◽  
Umbilical Cord Insertion

<b><i>Objective:</i></b> The objective of this study was to assess the position of the conus medullaris (CM) at the first trimester 3D ultrasound in a cohort of structurally normal fetuses. <b><i>Methods:</i></b> This was a multicenter prospective study involving a consecutive series of structurally normal fetuses between 11 and 13 weeks of gestation (CRL between 45 and 84 mm). All fetuses were submitted to 3D transvaginal ultrasound using a sagittal view of the spine as the starting plane of acquisition. At offline analysis, the position of the CM was evaluated by 2 independent operators with a quantitative and a qualitative method: (1) the distance between the most caudal part of the CM and the distal end of the coccyx (CMCd) was measured; (2) a line perpendicular to the fetal spine joining the tip of the CM to the anterior abdominal wall was traced to determine the level of this line in relation to the umbilical cord insertion (conus to abdomen line, CAL). Interobserver agreement for the CCMd was evaluated. Linear regression analysis was used to determine the association between the CMCd and CRL, and a normal range was computed based on the best-fit model. The absence of congenital anomalies was confirmed in all cases after birth. <b><i>Results:</i></b> In the study period between December 2019 and March 2020, 143 fetuses were recruited. In 130 fetuses (90.9%), the visualization of the CM was feasible. The mean value of the CMCd was 1.09 ± 0.16 cm. The 95% limits of agreement for the interobserver variability in measurement of the CMCd were 0.24 and 0.26 cm. The interobserver variability based on the intra-class correlation coefficient (ICC) for the CCMd was good (ICC = 0.81). We found a positive linear relationship between the CCMd and CRL. In all these fetuses, the CAL encountered the abdominal wall at or above the level of the cord insertion. <b><i>Conclusion:</i></b> In normal fetuses, the assessment of the CM position is feasible at the first trimester 3D ultrasound with a good interobserver agreement. The CM level was never found below the fetal umbilical cord insertion, while the CMCd was noted to increase according to the gestational age, confirming the “ascension” of the CM during fetal life.

scholarly journals Uterine fluid composition of the dwarf ornate wobbegong shark (Orectolobus ornatus) during gestation

2011 ◽  
Vol 62 (6) ◽  
pp. 576 ◽  
Author(s):  
Megan T. Ellis ◽  
Nicholas M. Otway
Keyword(s):  
Reproductive Biology ◽  
Coastal Waters ◽  
Reproductive Strategies ◽  
Yolk Sac ◽  
Gestation Period ◽  
Fluid Composition ◽  
Complex Composition ◽  
Eastern Australia ◽  
Uterine Fluid ◽  
Low Levels

Low fecundity in chondrichthyans makes them extremely susceptible to fishing, so understanding the various reproductive strategies in this group is vital for management. Knowledge of the uterine fluid (UF) composition throughout gestation is fundamental to this understanding, yet is restricted to a few species. This study focussed on the UF composition of the wobbegong (Orectolobus ornatus), which inhabits coastal waters off eastern Australia. The UF was quantified throughout pregnancy. Fluids surrounding uterine eggs had a complex composition, with mean urea (98.48 mmol L–1), sodium (560.25 mmol L–1) and potassium (13.93 mmol L–1) concentrations significantly greater than those in seawater. A change in composition, from complex to simple, occurred after 3–4 months gestation. Major electrolyte concentrations then resembled seawater for the remainder of gestation, suggesting the flushing of the uteri with seawater and evidenced by fluctuating low levels of urea. The gestation period reflected the time for metabolism of yolk stores, osmotic and ionic adjustment, development of functioning immunological systems and prevention of external yolk sac damage. Our study is the first documentation of UF composition for a wobbegong shark and increases understanding of its reproductive biology.

Spatiotemporal expression of three gap junction gene products involved in fetomaternal communication during rat pregnancy

Development ◽  
1991 ◽  
Vol 113 (1) ◽  
pp. 165-181 ◽  
Author(s):  
B. Risek ◽  
N.B. Gilula
Keyword(s):  
Gap Junction ◽  
Post Partum ◽  
Giant Cells ◽  
Yolk Sac ◽  
Chorionic Villi ◽  
Pregnant Uterus ◽  
Decidual Cells ◽  
Visceral Yolk Sac ◽  
Beta 2 ◽  
Specific Regulation

The expression of three different members of the gap junction multigene family, alpha 1 (Cx43), beta 1 (Cx32), and beta 2 (Cx26), was analysed in the rat implantation chamber (a structural unit containing fetal, extraembryonic and maternal components within the pregnant uterus) during mid- and late stages of gestation as well as in the delivering, post-partum and non-pregnant uterus. A differential, spatiotemporal and cell-type-specific regulation of gap junctional coexpression was observed for beta 1 and beta 2 in all epithelia examined (visceral, luminal and glandular), as well as for alpha 1 and beta 2 in decidual cells and keratinocytes of the fetal epidermis. alpha 1 antigen was detected in the mesometrial stroma, mesometrial myometrium, connective tissue, mesothelia of the amnion and visceral yolk sac and in the allantoic mesodermal layer throughout gestation. In addition, expression of alpha 1 in the placental basal zone and trophoblast giant cells coincided with the differentiation of these cells. beta 2 expression was observed prominently in the chorionic villi of the placental labyrinth. The presence of beta 1 and beta 2 in the visceral epithelium (visceral yolk sac = the primary route for embryonic nourishment prior to the formation of the chorioallantoic placenta) and beta 2 in the chorionic villi (placental barrier = the major fetomaternal exchange route) suggests that gap junctions have an important role in fetomaternal communication.

Transfer of radioactive iron via the placenta and accessory fetal membranes in the rabbit

1959 ◽  
Vol 197 (1) ◽  
pp. 87-92 ◽  
Author(s):  
J. Davies ◽  
E. B. Brown ◽  
D. Stewart ◽  
C. W. Terry ◽  
J. Sisson
Keyword(s):  
Sharp Increase ◽  
Iron Transport ◽  
Fetal Liver ◽  
Uterine Cavity ◽  
Yolk Sac ◽  
Fetal Membranes ◽  
Steady Increase ◽  
Iron Transfer ◽  
Uterine Mucosa ◽  
Alternative Sites

The distribution of radioactivity in the fetus and placental structures was studied at different stages of gestation in the rabbit following the intravenous injection of radioactive iron as Fe59 sulphate. The following general results were obtained: a) A steady increase in the uptake of radioiron by the fetus and fetal placenta took place with advancing gestation. The rate of uptake showed a sharp increase at about the 20th day. b) The rate of iron transport across the placenta increased during gestation, especially in the last third of pregnancy. c) Radioiron was concentrated in the yolk sac in the early stages and in the fetal liver in the later stages of gestation. No change in the pattern of accumulation of radioiron by the fetus took place when the vessels of the yolk sac were ligated before injection. These results suggest that the yolk sac has no role in iron transport and that early in gestation it may carry on some of the functions of the fetal liver with respect to iron. d) Alternative sites of transport for iron were investigated by the injection of radioiron into the uterine cavity. The results indicate that if iron gains access to the uterine cavity, e.g. via the uterine mucosa or via the chorion and periplacental decidua, it is rapidly absorbed by the yolk sac and enters the fetus. However, such a pathway for iron transfer to the fetus does not seem to be important physiologically.

532. SOLUBLE MEDIATORS IN THE HUMAN UTERINE CAVITY: POTENTIAL ROLES IN EMBRYO IMPLANTATION

2009 ◽  
Vol 21 (9) ◽  
pp. 130
Author(s):  
N. Hannan ◽  
K. L. Meehan ◽  
L. J. F. Rombauts ◽  
L. A. Salamonsen
Keyword(s):  
Chemokine Receptors ◽  
Embryo Implantation ◽  
Uterine Cavity ◽  
Cycle Phase ◽  
Human Trophoblast ◽  
Endometrial Epithelial Cell ◽  
Glandular Secretion ◽  
Uterine Fluid ◽  
Human Chemokines ◽  
Insight Into

Embryo implantation requires synchronized dialogue between a receptive endometrium and an activated blastocyst via locally produced soluble mediators. During the mid-secretory (MS) phase of the menstrual cycle there is increased glandular secretion into the uterine lumen. These secretions likely contain important mediators that modulate the endometrium and support the conceptus during implantation. Previously we identified that several chemokines were maximally produced during the MS phase by endometrial glandular epithelium (GE) (1, 2) and the presence of chemokine receptors on GE and human trophoblast (3). Furthermore recombinant human chemokines and endometrial epithelial cell-conditioned media stimulated trophoblast migration; this was attenuated by neutralizing specific chemokines (3). Chemokines also regulate a variety of adhesion and ECM molecules on trophoblast (4). Thus chemokines have important roles during embryo implantation. We hypothesized that chemokines are secreted into the uterine cavity and may act on the implanting blastocyst and the endometrium. This study aimed to identify chemokines in uterine fluid (collected by flushing the uterine cavity with 5mls of saline) from fertile women during the proliferative (non-receptive; n=4) and MS (receptive; n=4) phases of the cycle, and from women with unexplained infertility during the MS phase (n=4). Uterine fluid was analyzed using quantitative MilliplexTM Luminex® 42-plex cytokine/chemokine assays revealing the presence of IL-8, CCL2, CCL4, CCL7, CCL11, CCL22 and CX3CL1 in uterine fluid from all women. Importantly chemokine profiles were altered with both cycle phase and fertility; for example CCL4 and CCL22 levels were lower in the infertile cohort, where as CCL2 levels were higher in uterine fluid collected during the proliferative phase. Identifying the soluble mediators in human uterine fluid may provide potential markers of endometrial receptivity, insight into the unique microenvironment essential for pregnancy and a profile of maternal factors that influence the implanting blastocyst.

Passage of maternal immunoglobulins to the pouch young of a marsupial. Setonix brachyurus

1973 ◽  
Vol 21 (2) ◽  
pp. 171 ◽  
Author(s):  
M Yadav ◽  
M Eadie
Keyword(s):  
Amniotic Fluid ◽  
Serum Antibody ◽  
Allantoic Fluid ◽  
Yolk Sac ◽  
Milk Whey ◽  
Serum Immunoglobulins ◽  
Antibody Titres ◽  
Uterine Fluid

Prenatal and precolostral newborn quokkas, S. brachyurus, had no immunoglobulins in their serum. Immunoglobulins were not detected in the yolk-sac fluid, the amniotic fluid, or the allantoic fluid, but were present in the uterine fluid, the colostrum, and milk whey. Immunoglobulins were present in the serum of neonatal quokkas that had suckled for at least 24 hr. Initial immunization of a female with Salmonella adelaide flagella and bacteriophage 0 x 174 antigen resulted in high titres of antibodies in her blood 1 week later, but there was a lag of less than 1 week before anti-S. adelaide agglutinins and a lag of 2 weeks before antiphage antibodies were detectable in the serum of the suckling pouch young. A further delay of 2 weeks occurred before serum antibody titres were as high in pouch young as they were in the mother. At no time in development did antibody titres in the sera of pouch young exceed those of the mother. The ability to absorb antibody in the gut ceased 2-3 weeks after the 6-month-old young left the pouch.

HISTOCHEMICAL DISTRIBUTION OF SOME HYDROXYSTEROID DEHYDROGENASES IN THE PLACENTA, FOETAL MEMBRANES AND UTERINE MUCOSA OF THE MOUSE

1968 ◽  
Vol 40 (2) ◽  
pp. 189-NP ◽  
Author(s):  
V. BOTTE ◽  
S. TRAMONTANA ◽  
G. CHIEFFI
Keyword(s):  
First Generation ◽  
Second Generation ◽  
Giant Cells ◽  
Yolk Sac ◽  
Histochemical Reaction ◽  
Hydroxysteroid Dehydrogenases ◽  
Foetal Membranes ◽  
Uterine Mucosa ◽  
Endodermal Cells ◽  
Yolk Sac Placenta

SUMMARY The placenta, foetal membranes and uterine mucosa of mice (pregnant for 8–17 days) have been investigated by histochemical methods for NAD-dependent 3β-hydroxysteroid dehydrogenase (3β-HSDH), and for NAD-and NADP-dependent 17α- and 17β-hydroxysteroid dehydrogenases (17α- and 17β-HSDH), 11α- and 11β-hydroxysteroid dehydrogenases (11α- and 11β-HSDH), and 20β-hydroxysteroid dehydrogenase (20β-HSDH). 3β-HSDH was found to be distributed in the trophoblastic giant cells of the first generation with both pregnenolone and DHA as substrates, and in the giant cells of the second generation and of the labyrinth and the endodermal cells of the inverted yolk sac placenta, but only with DHA as substrate. 17α-HSDH and 17β-HSDH, NAD-dependent, were present in both the first and second generation giant cells and in the giant cells of the labyrinth as well as in the endodermal cells of the inverted yolk sac placenta. With NADP as cofactor, 17α-HSDH and 17β-HSDH were weakly positive with all the substrates used in the giant cells of the second generation and of the labyrinth, while NADP-dependent 17β-HSDH was present in the first generation giant cells and in the endodermal cells of the inverted yolk sac placenta but only with oestradiol-17β as substrate. The histochemical reaction for 11α-HSDH, both NAD- and NADP-dependent, was limited to trophoblastic giant cells of the second generation and of the labyrinth; 11β-HSDH, both NAD- and NADP- dependent, was distributed in the giant cells of the second generation and of the labyrinth, the epithelial cells of the uterine mucosa and the decidua basalis. The histochemical reaction for 20β-HSDH, NAD- and NADP-dependent, was weakly positive in the giant cells of the first generation only.

scholarly journals Embryonic Annexes

2018 ◽  
Vol 1 (4) ◽  
pp. 301-309
Author(s):  
Mariana Rojas ◽  
Ángel Rodríguez
Keyword(s):  
Germ Cells ◽  
Primordial Germ Cells ◽  
Chorionic Villus ◽  
Yolk Sac ◽  
Placental Lactogen ◽  
Mechanical Trauma ◽  
Temperature Changes ◽  
Suspensory Ligament ◽  
Different Types ◽  
Extraembryonic Membranes

In vertebrates, depending on the environment in which an embryo develops, different types of extraembryonic membranes are formed. In placental mammals the following extraembryonic membranes are formed: amnion, yolk sac, allantois, chorion and placenta. Extraembryonic membranes perform functions vital to the embryo. The amnion protects the embryo from drying, the mechanical trauma, temperature changes and adhesions which can distort it. The yolk sac is present in all vertebrates. In mammals allows the formation of the first blood vessels and the first blood, home to the primordial germ cells for some time; however, in fish and birds these have nutritional importance. In birds and mammals such as cattle, sheep and pig the allantois receives urinary wastes; this structure also contributes part of the bladder and at the time of birth becomes the suspensory ligament, urachus. The chorion form chorionic villus, which can produce hormones such as chorionic gonadotropin and human placental lactogen. A portion of the chorionic sac helps form the placenta.

155. UNDERSTANDING THE CROSSTALK IN THE HUMAN UTERINE CAVITY: ROLES FOR SOLUBLE MEDIATORS DURING EMBRYO IMPLANTATION

2010 ◽  
Vol 22 (9) ◽  
pp. 73
Author(s):  
N. Hannan ◽  
P. Paiva ◽  
K. L. Meehan ◽  
C. Hincks ◽  
L. J. F. Rombauts ◽  
...  
Keyword(s):  
Menstrual Cycle ◽  
Embryo Implantation ◽  
Uterine Cavity ◽  
Uterine Receptivity ◽  
Adhesive Properties ◽  
Infertile Women ◽  
Functional Studies ◽  
Glandular Secretion ◽  
Uterine Fluid ◽  
Insight Into

Embryo implantation requires synchronized dialogue between a receptive endometrium and an activated blastocyst via locally produced soluble mediators. During the mid-secretory (MS) phase of the menstrual cycle there is increased glandular secretion into the uterine lumen. These secretions contain important mediators that modulate the endometrium and support the conceptus during implantation. Analysis of the composition of uterine fluid across the menstrual cycle and in fertile and infertile women will, therefore, provide new insights into uterine receptivity. We hypothesized that multiplex platform analysis of human uterine lavages would identify soluble mediators important for the establishment of pregnancy in humans. Lavages were collected (by flushing the uterine cavity with 5mL of saline) from fertile and infertile women during the MS phase and from fertile women during the mid-proliferative (MP) phase of the menstrual cycle. Comparison of lavages from the three cohorts was performed using quantitative MilliplexTM Luminex® cytokine/chemokine assays containing 42-analytes. Luminex analysis detected a number of cytokines in uterine fluid, revealing 8 soluble mediators previously unknown in the endometrium and present in human uterine fluid including, PDGF-AA, TNFβ, sIL-2Rα, Flt-3 ligand, sCD40L, IL-7, IFNα2 and GRO. Furthermore comparison of the three cohorts revealed VEGF levels were significantly higher in the fertile (MS) fluid when compared to infertile. Functional studies demonstrated that rhVEGF treatment significantly increased the adhesive properties in cells present at the maternal-fetal interface. These findings suggest VEGF plays a role in regulating embryo implantation. Furthermore identifying the soluble mediators in uterine fluid may provide potential markers of endometrial receptivity, insight into the unique microenvironment essential for pregnancy and a profile of maternal factors that influence the implanting blastocyst.

Placenta, Umbilical Cord and Foetal Membranes

2007 ◽  
pp. 34-34
Author(s):  
Sudha Salhan ◽  
Harsha Gaikwad ◽  
Indira Ganeshan ◽  
Meetu Salhan
Keyword(s):  
Umbilical Cord ◽  
Foetal Membranes
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