PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “VITELLINE DUCT”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources

[A rare cause of intestinal obstruction revealed during pregnancy (Kamenge University Hospital Center, Bujumbura, Burundi)].

Acute intestinal occlusion is rare during pregnancy, and more exceptional is the source itself of the occlusion we are reporting embryonic. This is actually an embryonic remains: the omphalo-mesenteric (vitellin) duct that did not resorb and has developed into a fibrous cord. The latter, owing to physiological modifications, is responsible of the occlusion. The authors analyse the two facts which, when associated, represent an interesting clinical fact.

Adult↗

Assessment of the umbilical cord outside of the delivery room. Part 2.

The umbilical cord is crucial to the growth and development of the fetus. Careful inspection in the delivery room and throughout the newborn period is essential. Part 1 of this 2-part series, entitled "Look Before You Clamp: Delivery Room Examination of the Umbilical Cord" (Advances in Neonatal Care, Vol. 2, No. 1, pp 19-26), reviewed umbilical problems that present in the delivery room. A number of subtle but significant umbilical cord abnormalities present outside the delivery room. These abnormalities will be the focus of Part 2 of this series. A review of the embryologic development of the umbilical cord enhances the clinician's understanding of umbilical abnormalities that present in the newborn period. The process of umbilical cord separation is outlined. Conditions associated with delayed cord separation are discussed. A systematic approach to the physical examination of the umbilicus is offered, with an emphasis on early detection of abnormalities. Common and uncommon physical findings, such as omphalitis, periumbilical necrotizing fascitis, vitelline duct remnants, and urachal anomalies are presented along with select photographs. A brief discussion of the clinical implications for newborn care is provided for the practicing clinician.

Delivery Rooms↗

An unusual presentation of patent urachus: report of a case.

Congenital umbilical disorders are frequently seen in the pediatric population and are mostly classified as retained umbilical cord structures or failure of umbilical ring closure. Vitelline duct anomalies, urachal anomalies and umbilical herniations comprise the main group of these congenital problems. Here we report a new presentation of vesicoumbilical patency in a 20-day-old male baby. A brief review of the literature concerning the classification of patent urachus to explain the possible mechanism of the anomaly is given.

Hernia, Umbilical↗

A neonate with an intact congenital umbilical appendix: an alternative theory on the etiology of the appendico-umbilical fistula.

Neonatal umbilical anomalies usually represent remains of the vitelline duct or the allantois. We describe a case of an umbilical appendix in a neonate. The vermiform appendix was found to be positioned in the umbilical cord. In a brief literature review we found eight other reports concerning umbilical appendices. In this article we describe a possible embryological explanation for the development of an umbilical appendix, and discuss whether or not the appendiceal umbilical fistulae reported are congenital or iatrogenic. The possible association between an umbilical appendix and different forms of malpositioning and rotation of the gut is also discussed. Protrusion of the neonatal appendix into the umbilical cord represents a different entity of congenital anomalies. It is important to realize that, in the case of an unrecognized umbilical appendix, medical procedures (e.g., canulation or clamping of the umbilicus) may produce an iatrogenic appendico-umbilical fistula. Careful inspection and palpation of the umbilical cord prior to these procedures may prevent a fistula being created. Furthermore, because the possible association between umbilical appendices and different kinds of malpositioning of the gut is so far not wholly elucidated, we recommend further (radiological) investigation in each case of an umbilical appendix. Correct positioning of the bowel needs to be confirmed in order to rule out possible future complications.

Appendectomy↗

Changes in the spermatozoon during fertilization in Hydroides hexagonus (Annelida). I. Passage of the acrosomal region through the vitelline membrane.

In the previous paper the structure of the acrosomal region of the spermatozoon was described. The present paper describes the changes which this region undergoes during passage through the vitelline membrane. The material used consisted of moderately polyspermic eggs of Hydroides hexagonus, osmium-fixed usually 9 seconds after insemination. There are essentially four major changes in the acrosome during passage of the sperm head through the vitelline membrane. First, the acrosome breaks open apically by a kind of dehiscence which results in the formation of a well defined orifice. Around the lips of the orifice the edges of the plasma and acrosomal membranes are then found to be fused to form a continuous membranous sheet. Second, the walls of the acrosomal vesicle are completely everted, and this appears to be the means by which the apex of the sperm head is moved through the vitelline membrane. The lip of the orifice comes to lie deeper and deeper within the vitelline membrane. At the same time the lip itself is made up of constantly changing material as first the material of the outer zone and then that of the intermediate zone everts. One is reminded of the lip of an amphibian blastopore, which during gastrulation maintains its morphological identity as a lip but is nevertheless made up of constantly changing cells, with constantly changing outline and even constantly changing position. Third, the large acrosomal granule rapidly disappears. This disappearance is closely correlated with a corresponding disappearance of a part of the principal material of the vitelline membrane from before it, and the suggestion is made that the acrosomal granule is the source of the lysin which dissolves this part of the vitelline membrane. Fourth, in the inner zone the fifteen or so short tubular invaginations of the acrosomal membrane, present in the normal unreacted spermatozoon, lengthen considerably to become a tuft of acrosomal tubules. These tubules are the first structures of the advancing sperm head to touch the plasma membrane of the egg. It is notable that the surface of the acrosomal tubules which once faced into the closed acrosomal cavity becomes the first part of the sperm plasma membrane to meet the plasma membrane of the egg. The acrosomal tubules of Hydroides, which arise simply by lengthening of already existing shorter tubules, are considered to represent the acrosome filaments of other species.

Acrosome↗

A new description of the reproductive system of Schistosoma mansoni (Trematoda: Schistosomatidae) analyzed by confocal laser scanning microscopy.

Classical schemes of the adult Schistosoma mansoni reproductive system have been described. In our study, whole adult worms derived from unisexual or mixed infections and stained with carmine chlorine were virtually and tomographically analyzed under confocal laser scanning microscopy. We found that: (1) there were morphological differences in the ovary, vitteline glands and testicular lobes between specimens derived from unisexual or mixed infections; (2) there was always a single lobed ovary (three or four lobes), presenting differentiation from the anterior to the posterior lobes, where the most mature oocytes were located; (3) the proximal segment of oviduct was connected to an ampullary dilatation, full of tailed spermatozoa, characterizing a seminal receptacle; (4) there was no long vitelline duct, but a short one that begins at the end of the proximal region of the vitelline gland; (5) long cells of Mehlis' gland placed radially around the ootype were not observed. Otherwise, the ootype was only lined by thick cuboidal epithelial cells with plaited bases and nuclei with flabby chromatin, making a clear distinction from the uterine epithelium. This morphological feature suggests that each cell represents a gland. (6) In coupled males, the specimens located inside the gynaecophoric canal had smaller testicular lobes, suckers, and body length and width when compared to their partners. Our results show that the reproductive system does not follow a unique pattern within flatworms. Due to its better resolution, confocal laser scanning microscopy, using a reflected mode with tomographic sections, allows new interpretations, modifying the adopted and current descriptions of the internal morphological structures of S. mansoni adult worms.

Animals↗

Scanning and transmission electron microscopy of the female reproductive system of Schistosoma margrebowiei Le Roux, 1933.

Transmission electron microscopy shows that the uterus of female Schistosoma margrebowiei possesses the same ultrastructure as that of the tegument but lacks spines and sense organs. It does not possess secretory cells and opens at the gonopore which by scanning electron microscopy was seen to be composed of numerous leaf-like protrusions. The morphology of the ovary is comparable with that of other Digenea. Immature and mature ova possess cortically arranged granules and occur within the posterior zone of the ovary. Cilia and lamellae line the luminal surface of the oviduct and ootype, the lamellae running unidirectionally along the duct. Only a single type of secretory cell is seen within Mehlis' gland and this produces dense bodies which are associated with Goldi bodies. Narrow cytoplasmic channels supported by microtubules deliver these secretory bodies to the ootype. The vitelline duct is lined with cilia and lamellae and the vitelline gland contains four types of cells, S1, S2, S3 and S4. Calcareous corpuscles are found within mature S4 cells.

Animals↗

Immunohistochemical localization of connective tissue growth factor (CTGF) in the mouse embryo between days 7.5 and 14.5 of gestation.

Connective tissue growth factor (CTGF) is a 38 kDa modular protein that is involved in processes such as cell proliferation, survival, migration, adhesion and extracellular matrix production. Target cells for CTGF include fibroblasts, smooth muscle cells and endothelial cells. Using a specific peptide antibody, CTGF was localized in tissue sections obtained from mouse embryos between days 7.5 and 14.5 of gestation. On day 7.5, CTGF was present at high levels in the embryonic ectoderm, mesoderm, and chorion, with weaker levels in the squamous endoderm. No CTGF was detected in Reichert's membrane, parietal endoderm, and visceral endoderm. Decidual cells of the maternal uterus stained strongly for CTGF. There was no specific staining for CTGF on day 11.5 but by day 13.5, the protein was detectable in a limited number of structures, most notably the liver, thymus, lung, and intestine. By day 14.5, staining for CTGF had become extensive and was present at high or moderate levels in the thymus, aorta, trachea, liver, lung, adrenal gland, kidney, iliac sinus, olfactory region, tongue, pharynx, esophagus, thyroglossal duct, choroid plexi, Rathke's pouch, stomach, pancreas, and midgut. Relatively weak staining was present in the heart and dorsal root ganglia. There was no staining in the vitelline duct or in the outer cortical or medullary regions of the brain. Among specific cell types, CTGF was localized at high levels in secretory and absorptive epithelial cells and liver parenchyma cells, at moderate levels in vascular endothelial cells and myoblasts and at low levels in mesenchymal and connective tissue cells. These data show that various tissues and organ systems produce CTGF in a specific temporo-spatial pattern during embryogenesis and support a role for CTGF in cellular differentiation and development during prenatal life.

Animals↗

Segmental mega-ileum presenting as anaemia.

Three cases are described of an unusual malformation of the ileum at the site of the vitelline duct, which presented with chronic anaemia. In each case localized mega-ileum was associated with a simple, non-specific ulcer leading to chronic blood loss. Two cases were at the site of and associated with a Meckel's diverticulum, while the third case was at the same level and associated with a vascular abnormality probably of vitelline artery origin. Ths syndrome of adult segmental ileal dilatation associated with non-specific ulcer and chronic anaemia does not appear to have been described previously.

Abnormalities, Multiple↗

[The study of the ultrastructure of the female reproductive system in a parasite of bats Allassogonoporus amphoraeformis (Digenea: Allassogonoporidae)].

The morphology and fine structure of the female reproductive system of allassogonoporid trematode Allassogonoporus amphoraeformis have been described for the first time. The ovary consists of the germ cells being at various developmental stages and supporting cells of two types. The oviduct, seminal receptacle with its short duct and the proximal portion of Laurer's canal are lined by flattened cellular epithelium with lamellae and cilia on its luminal surface and well-developed basal infoldings. The distal part of Laurer's canal and metraterm are tegumental in structure and are characterized by sparse secretory inclusions and lacking of spines. Mehlis' glands of two types open into ootype. The uterus wall is composed of highly flattened epithelial cells surrounded by basal lamina and sparse muscle bundles. Vitelline lobules consist only of the vitelline cells at various developmental stages. The mature vitelline cells contain two types of inclusions: vitelline droplets and rarely scattered lipids. Vitelline ducts are lined by cellular epithelium with highly folded luminal surface and devoid of cilia. Presented results are compared with earlier obtained data on other lecithodendrioiden trematode Prosthodendrium ascidia ([symbol: see text], 1990).

Animals↗

Possible mechanisms of cadmium fetotoxicity in golden hamsters and mice: uptake by the embryo, placenta and ovary.

Pregnant golden hamsters and mice of different gestational ages were injected intravenously with 109CdCl(2). The whole animal or the uterus and embryos were submitted to autoradiography. Cadmium administered on the 8th day accumulated in the primitive gut of the embryos. No cadmium was detected in the embryos after administration on or after the 9th day (hamster) and 11th day (mouse). This finding can be explained by the ability of cadmium to pass from the yolk-sac cavity into the primitive gut (where it is absorbed) before the closure of the vitelline duct but not later. This uptake by the embryo might explain the severe malformations produced by cadmium given on the 8th day as compared with the 9th day in the hamster. Cadmium is also heavily accumulated in the decidua (mainly the antimesometrial part), the yolk sac, the ectoplacental cone, and later in the chorioallantoic placenta-possibly disturbing the maternal-embryonic relationship and fetal nutrition. A high accumulation in the CL and the follicles and in the pituitary may also disturb reproductive function.

Animals↗

Hemopoiesis in the human yolk sac.

The endodermal layer of the human yolk sac was examined three-dimensionally with light microscopy on serial sections using scanning electron microscopy and transmission electron microscopy to find the origin of hemopoiesis in the yolk sac. Cell-labelling techniques were also employed using the monoclonal anti-transferrin receptor antibody. Orifices of the endodermal and intracellular tubules facing the yolk-sac cavity were demonstrated on the endodermal surface. Various-sized blood cells in various stages of differentiation and maturation were distributed in the yolk-sac cavity and tubules and were observed also at the orifices of the tubules. The morphological and the immunological findings suggest that blood cells with large nuclei in the endodermal layer are the most immature. The present results suggest that blood cells originate from the endodermal layer and are carried to the embryo through the yolk sac cavity and the vitelline duct. It is probable that the endodermal and intracellular systems of tubules have an important role in the transport of blood cells, including stem cells.

Antibodies, Monoclonal↗

Coexistence of a Meckel's diverticulum and a urachal remnant.

Meckel's diverticulum, which is a remnant of the omphalomesenteric or vitelline duct, is the most common congenital abnormality of the gastrointestinal system. Urachal abnormalities, resulting from anomalous urogenital development, are not observed frequently and case reports are mainly represented in literature. The presence of these two congenital anomalies together is a very rare pathology. Complications arising from a Meckel's diverticulum or urachal remnant may clinically mimic acute appendicitis and other surgical pathologies. We report on a patient who underwent surgery for acute appendicitis when it was discovered that the symptoms were produced by a perforated Meckel's diverticulitis. In the course of the surgery, a urachal remnant was found to coexist with the diverticulum.

Adolescent↗

The differentiation of clonal rat yolk sac tumor cell lines cultivated with dibutyryl-cyclic 3', 5'-adenosine monophosphate.

Five rat yolk sac tumor cell lines were cloned from a yolk sac tumor line which originally arose following fetectomy. The doubling time of each of the cloned tumor lines was about 50 h. All of the cloned tumor cell lines synthesized and secreted AFP and albumin but there was a gradual decrease in the synthesis of these proteins during serial passage. The cells formed clusters which looked like vitelline ducts or the parietal yolk sac and they also had basement membranes which closely resembled Reichert's membrane. When the cloned cell lines were cultivated in the presence of 1 mM dibutyryl cyclic-AMP, myotube-like and neuron-like cells appeared. Acetylcholine esterase and creatine phosphokinase activity were present when myotube-like cells were present whereas acetylcholine esterase activity predominated when neuron-like cells were present.

Acetylcholinesterase↗

Histological analysis of spontaneous abortions with trisomy 2: first description of an embryo.

Three spontaneous abortions with trisomy 2 were analyzed histologically. In one of these, beside chorionic membranes and villi, yolk sac, yolk stalk, body stalk and an embryo are described. Concerning the development stage there seems to be an order; villi and body stalk (16 days), embryo (end of 3rd week to beginning of 4th week) and yolk sac with yolk stalk (2nd half of 4th week).

Abortion, Missed↗

The lining of the gut in the developing rat embryo. Its relation to the hypoblast (primary endoderm) and the notochord.

A light microscopical study of the morphogenesis of the gut in the rat embryo was undertaken to provide a careful map of temporal changes in the topographical relations of the (definitive) endoderm, the notochord and the hypoblast (primary endoderm). The borderline between the (definitive) endoderm and the hypoblast that appears upon gastrulation defines the lateral extension of the future gut epithelium. Within this initially semiglobular disk, the foregut and hindgut originate sequentially as blind, rapidly growing pouches. Upon the turning of the embryo, the hardly growing peripheral part of the disk becomes located in the vitelline duct. Within the head process, endodermal and notochordal cells could not be separately identified. However, slightly more posteriorly notochordal cells are seen to become embedded into the endoderm of the foregut during gastrulation. This process is not seen over the hindgut and may explain why the detachment of the notochord from the (fore)gut begins caudally.

Animals↗

CT manifestations of ileal dysgenesis.

Ileal dysgenesis is an uncommon condition of unknown etiology occurring in the distal ileum in the region of the vitelline duct. The CT appearance of this lesion, although not previously described to our knowledge, is characteristic. We report a patient with ileal dysgenesis who had an abdominal CT scan to evaluate chronic iron deficiency anemia and protein-losing enteropathy. Recognition of this lesion by pediatric radiologists is important; so that surgical treatment, which is simple and effective, can be initiated quickly.

Anemia, Iron-Deficiency↗