Primitive Intestine Research Articles

"Tailgut cyst" : decipher the enigma to be more informed. Case experience

The "Tailgut cyst" is a unique dysontogenetic entity, whose source of origin is marked by the postnatal persistence of the primitive intestine in the presacral space. Predominantly female in distribution, this generally benign congenital tumor can experience malignant degenerative changes to varying degrees. Given its rarity, its location and its non-specific clinical footprint, the condition most often constitutes a diagnostic dilemma. The management of the pathology is surgical excision, considered as the curative treatment also allowing a final histopathological diagnosis. In this report, we present the case of a woman with a history of Tailgut cyst diagnosed by imaging following exploration for pelvic discomfort and which was successfully managed and pathologically confirmed to be benign after complete surgical resection. We are reviewing the literature to improve understanding and increase awareness of this exceptional clinical scenario in our workflow

Intestinal DHA-PA-PG axis promotes digestive organ expansion by mediating usage of maternally deposited yolk lipids

Although the metabolism of yolk lipids such as docosahexaenoic acid (DHA) is pivotal for embryonic development, the underlying mechanism remains elusive. Here we find that the zebrafish hydroxysteroid (17-β) dehydrogenase 12a (hsd17b12a), which encodes an intestinal epithelial-specific enzyme, is essential for the biosynthesis of long-chain polyunsaturated fatty acids in primitive intestine of larval fish. The deficiency of hsd17b12a leads to severe developmental defects in the primitive intestine and exocrine pancreas. Mechanistically, hsd17b12a deficiency interrupts DHA synthesis from essential fatty acids derived from yolk-deposited triglycerides, and consequently disrupts the intestinal DHA-phosphatidic acid (PA)-phosphatidylglycerol (PG) axis. This ultimately results in developmental defects of digestive organs, primarily driven by ferroptosis. Our findings indicate that the DHA-PA-PG axis in the primitive intestine facilitates the uptake of yolk lipids and promotes the expansion of digestive organs, thereby uncovering a mechanism through which DHA regulates embryonic development.

Intestinal Malrotation, Mesocolic Hernia, and Meckel Diverticulum – Differential Diagnosis of Abdominal Pain in Adults: Case Report and Literature Review

AbstractIntestinal malrotation is a congenital anomaly caused by incomplete rotation or absence of rotation of the primitive intestine along the axis of the upper mesenteric artery during embryonic development. Embryonic development and its anatomical variations were described by Dott in 1923.Intestinal malrotation is a rare condition among adults – prevalent in a mere 0.0001% to 0.19% of the population –, and it may be associated with other anatomical deformities. It can be asymptomatic or manifest with varying intensity, from obstruction to necrosis of intestinal segments. In general, this abnormality is diagnosed in the first year of life; however, symptoms may appear later in life, making diagnosis in adults difficult on account of non-specific symptoms.In the present study, we report a case of intestinal malrotation associated with chronic non-specific symptoms progressing to mesenteric angina.

Quiste pulmonar congénito como causa de neumonías recurrentes. A propósito de un caso

Introducción: Un quiste pulmonar se define como un espacio de parénquima pulmonar que contiene aire o líquido; se presentan asintomáticos o con infecciones respiratorias recurrentes. Se desarrolla por la separación de un segmento de uno de los bronquios principales, como resultado de una gemación anómala del intestino primitivo, con predilección por los lóbulos pulmonares inferiores. Tiene una incidencia mundial baja y pocos casos reportados por la literatura. 
 Objetivo: Describir un caso clínico de Quiste pulmonar congénito como causa de neumonías recurrentes Material y métodos: Estudio descriptivo retrospectivo, presentación de caso clínico. 
 Resultados: Se presenta el caso de una preescolar de 4 años con antecedente de infecciones respiratorias a repetición que es diagnosticada de quiste pulmonar congénito mediante hallazgos imagenológicos, durante el estudio de la patología respiratoria recurrente, tratada quirúrgicamente con lobectomía, con excelentes resultados.
 Conclusiones: Las infecciones respiratorias recurrentes es decir al menos 2 episodios en un año son la principal manifestación de los quistes pulmonares congénito en niños preescolares y escolares que requieren una investigación exhaustiva del aparato respiratorio del niño, ya que una de las principales causas son las malformaciones pulmonares, como es el quiste pulmonar

Pluripotency Markers in Stem Cells of Bats

Stem cells, a special kind of undifferentiated cells, are able indefinitely to go through mitotic cell division without losing their properties and produce differentiated cell lines. Due to their potential use in medicine, there is considerable research interest focusing in the study of embryonic stem cells and adult stem cells. Special emphasis has been placed on the study of embryonic germ cells, which characterized by expressing stem cell markers SSEA-1, SSEA-3, SSEA-4, TRA1-60, TRA1-8, alkaline phosphatase, periodic acid-Schiff and others. Stem cell research in bats could be the guide for further embryologic studies in other wild mammal species. We used SSEA-1, Oct-4, Stella, Sox-9 and Nanog stem cells markers (immunohistochemistry and RT-PCR) and observed the mRNA expression in bat embryos of A. jamaicensis and adult tissues of A. jamaicensis and B. plicata bats. An AP+ cell population and SSEA-1+ (primitive intestine) population were identified using markers during stages, 9, 10, 11 and 12 -the beginning of development. Other positive cell populations were identified (stages 11 and 12) using two other markers: PAS and Oct-4. On the other hand, we observed higher levels of mRNA expression of Oct-4 and Nanog in the first stages but not in more advances stages of development, and the expression of Stella and Sox-9 showed levels of expression alternating times along of stages. This is the first report of pluripotency markers of stem cells in A. jamaicensis, Oct-4 presence in functional gametes of B. plicata adults and the presence of Stella, Nanog and Sox-9 in bat embryonic and adult tissues.

Quiste de duplicación esofágica. Informe de un caso y revisión de la literatura

Los quistes congénitos del mediastino no son frecuentes; su prevalencia en la población adulta es mayor que en los niños. El quiste de duplicación esofágica es la segunda duplicación más frecuente del tubo digestivo después del íleo. Los quistes del intestino anterior (en la división embriológica del intestino primitivo hay intestino anterior y posterior) son el resultado de una división anormal del intestino pri- mitivo. Histológicamente son un saco muscular revestido de epitelio estratificado. La mayoría de estas anomalías son asintomáticas; en la mitad de los pacientes se descubren incidentalmente. En el abordaje diagnóstico del dolor torácico, los quistes del tubo digestivo son poco frecuentes; sin embargo, la fiebre y el dolor agudo pueden ser debidos a maceración o a su ruptura. Se ha descrito su asociación con anormalidades de la columna vertebral como espina bífida, hemivértebras o defectos de la fusión vertebral.

A morphological analysis of the transition between the embryonic primitive intestine and yolk sac in bovine embryos and fetuses

The yolk sac (YS) is the main source of embryonic nutrition during the period when the placenta has not yet formed. It is also responsible for hematopoiesis because the blood cells develop from it as part of the primitive embryonic circulation. The objective of this study was to characterize the transitional area between the YS and primitive gut using the techniques of light microscopy, transmission electron microscopy, and immunohistochemistry to detect populations of pluripotent cells by labeling with Oct4 antibody. In all investigated embryos, serial sections were made to permit the identification of this small, restricted area. We identified the YS connection with the primitive intestine and found that it is composed of many blood islands, which correspond to the vessels covered by vitelline and mesenchymal cells. We identified large numbers of hemangioblasts inside the vessels. The mesenchymal layer was thin and composed of elongated cells, and the vitelline endodermal membrane was composed of large, mono- or binucleated cells. The epithelium of the primitive intestine comprised stratified columnar cells and undifferentiated mesenchymal cells. The transitional area between the YS and the primitive intestine was very thin and composed of cells with irregular shapes, which formed a delicate lumen containing hemangioblasts. In the mesenchyme of the transitional area, there were a considerable number of small vessels containing hemangioblasts. Using Oct4 as a primary antibody, we identified positive cells in the metanephros, primordial gonad, and hepatic parenchyma as well as in YS cells, suggesting that these regions contain populations of pluripotent cells.

Structural analysis of oocytes, post-fertilization events and embryonic development of the Brazilian endangered teleost Brycon insignis (Characiformes)

The aim of this study was to evaluate the oocytes, post-fertilization events and embryonic development in Brycon insignis, under both scanning electron microscopy and stereomicroscopy. Oocytes and embryos were sampled from spawning up to hatching. Stripped oocytes were spherical, non-adhesive, greenish-brown, possessed a single micropyle, pore-canals and had a mean diameter of 1.46 mm. In 63% of oocytes the germinal vesicle was peripheric. The main post-fertilization events were the fertilization cone formation (20 s), micropyle closure (100-180 s) and agglutination of supernumerary spermatozoa (100-180 s). Embryonic development lasted 30 h at ~24 °C and was characterized by seven stages. Zygote, cleavage, blastula and gastrula stages were first observed at 0.25, 1, 3 and 6 h post-fertilization, respectively. Fertilization rate was determined at the moment of blastopore closure, 10-11 h post-fertilization. The segmentation stage began at 11 h post-fertilization and comprised the development of somites, notochord, optic, otic and Kupffer's vesicles, neural tube, primitive intestine, and development and release of the tail. The larval stage began 21 h post-fertilization and was characterized by the presence of somites, growth and elongation of the larvae. At the hatching stage, embryos presented vigorous contractions of the tail and body leading to chorion rupture (30 h). The morphological characteristics described for B. insignis were similar to that described for other teleost species, and such knowledge is important for a better understanding of reproductive features of a species and useful for ecological and conservational studies.

Structural analysis of the embryonic development inBrycon cephalus(Günther, 1869)

The embryogenesis of Brycon cephalus was established in seven stages: zygote, cleavage, blastula, gastrula, segmentation, larval and hatching, in an incubation period of 11 h (26 degrees C). The zygote phase was observed directly after fertilization and egg hydration. Cleavage began at 0.5 h of incubation and extended up to the morula phase (1.5 h; +100 blastomeres). Cleavage was meroblastic and underwent the following division pattern: the first five divisions were vertical and perpendicular to each other, following the model 2 x 2, 4 x 2, 4 x 4 and 4 x 8. The sixth division was horizontal and occurred at 1.25 h after fertilization, giving rise to two cell layers (4 x 8 x 2) with 64 blastomeres. At the blastula stage (1.25-1.5 h), an irregular space between the blastomeres, the blastocoele, could be detected and the periblast structure initiated. The gastrula (1.75-6.0 h) was characterized by the morphogenetic movements of epiboly, convergence and cell involution, and formation of the embryonic axis. The segmentation stage (7-9 h) comprised the development of somites, the notochord, optic, otic and Kupffer's vesicles, neural tube, primitive intestine and ended with the release of the tail. The larval stage (up to 10 h) was characterized by the presence of 30 somites and growth and elongation of the larvae. At the hatching stage, the embryos presented more than 30 somites and exhibited swimming movements and a soft chorion. The blastomeres presented euchromatic nuclei, indicating a high mitotic activity and many yolk globules in the cytoplasm. The periblast was constituted of a layer with several nuclei and many vesicles, which grew during the epiboly movement.

Embryonic development and skeletogenic gene expression affected by X-rays in the Mediterranean sea urchin Paracentrotus lividus

International concern over environmental nuclear contamination of salt water fisheries and coastal resources has attracted the interests of ecologists, marine biologists and stakeholders. There are not many studies on the effects of X-rays, a component of radionuclides emissions, on embryonic development and gene expression. The sea urchin embryo is emerging as a useful model system for environmental and eco-toxicological studies. Here, we describe how X-rays affect development and gene expression in embryos of the Mediterranean sea urchin Paracentrotus lividus. Cleavage embryos were exposed to doses from 0.1 to 5 Gy, using an Ag source of X radiation. We found a dose-dependent increase in developmental delays and severe morphological defects in embryos microscopically inspected at two endpoints, 24 and 48 h after irradiation. By analogy with classical toxicity tests parameters we defined the No Observed Effect Dose at 0.1 Gy, the Lowest Observed Effect Dose at 0.5 Gy and ED50 at 1.0 Gy. Major perturbations concerned primitive intestine and skeleton differentiation and development: X-rays exposed embryos had both no gut and arms or poorly and abnormally developed ones. We found a dose-dependent reduction in the mRNA levels of two skeleton-specific genes, Pl-SM30 (spicule matrix 30) and Pl-msp130 (matrix spicule protein 130), as measured by semi-quantitative RT-PCR and whole mount in situ hybridization, respectively. These findings indicate the sea urchin embryo as a sensible bioindicator of X-radiation and propose its use as an alternative model, emphasizing the need for further investigation aimed to protect ecosystem health.

Early fetal development of the small intestine mucosa in cattle (Bos primigenius taurus)

The development of the bovine small intestine was examined in 24 embryos and fetuses by light microscopic, scanning and transmission electron microscopic methods. Special reference was paid to the genesis of the epithelium and particularly of the villi intestinales. The primitive intestine consists of one layer of epithelial cells surrounded by mesenchym and tunica serosa. The fetal intestine (up to the 24th week of gestation) shows all the morphologic structures of the adult. In small intestine the development of cryptae and villi intestinales starts before the 7th week of gestation and progresses with a proximo-distal gradient. Epithelial proliferation that gives rise to primary epithelial villi makes epithelium become temporarily stratified. Finger-like secondary villi develop by proliferation of the mesenchym. In addition to this process mucosal folds occur in duodenum giving rise to villi by segmentation. At the same time the differentiation of epithelium starts. The fetal small intestine, like many other fetal tissues displays masses of glycogen.

Expression of the L-type pyruvate kinase gene and the hepatocyte nuclear factor 4 transcription factor in exocrine and endocrine pancreas.

The L-pyruvate kinase (L-PK) gene is slightly active in normal and tumoral endocrine pancreatic tissues while, in vivo, this gene is not transcribed in the exocrine pancreas. Nevertheless, the L-PK gene is re-expressed at a very low level in cultured 266.6 cells derived from an exocrine pancreas carcinoma. The L-PK gene is early activated in endodermal tissues, e.g. yolk sac and primitive intestine; it remains transcribed in fetal pancreas. In adult, L-PK gene expression is restricted to some endocrine cells. Hepatocyte nuclear factor (HNF) 1 and HNF4 are the main tissue-restricted transcription factors involved in tissue-specific expression of the L-PK gene. HNF1 concentration is similar in liver and all pancreatic cells. HNF4 concentration is high in liver, much lower in islets of Langerhans, endocrine pancreatic tumors, and cultured insulinoma cells, and is scarcely detectable in adult exocrine pancreas. This distribution of HNF4 parallels the expression of the L-PK gene. In vivo footprinting experiments show that the HNF1 binding site is similarly occupied in both adult liver and adult pancreas, in which this gene is practically inactive. In this latter tissue, however, the HNF4 binding site is differently occupied with respect to the liver. Since the chromatin structure remains open around the L-PK promoter in pancreas, the L-PK gene can probably be re-expressed under certain circumstances, for instance in cancerous pancreatic cells.

The urachus--an aid to the diagnosis of pneumoperitoneum.

Two findings diagnostic of pneumoperitoneum, which may be seen on roentgenograms taken in the supine position, have previously been described: (a) the visible outer surface of bowel loops (5) and (b) a visible falciform ligament (4). Another finding, the urachus conspicuously outlined by free air, made the diagnosis of pneumoperitoneum possible in the case reported below. Miller (2) noted that the urachus was occasionally visible on supine roentgenograms of infants with pneumoperitoneum, but no such adult case was found in our review of the literature. A 75-year-old female was admitted to St. Anthony's Hospital eight hours after the sudden onset of epigastric pain. Shortly prior to admission nausea and vomiting had occurred. There was no previous history of abdominal distress, weight loss, change of bowel habit, hematemesis, or melena. The patient had been taking cortisone for chronic arthritis. She had no history of genitourinary abnormality. Physical examination disclosed moderate abdominal distension. The umbilicus was in normal position. Tympany was elicited upon percussion of the abdomen. Bowel sounds were infrequent and high-pitched. Upper abdominal tenderness was present, without rebound. A complete blood count and urinalysis were normal. The blood urea nitrogen was 48 mg per 100 ml. A “fiat film” of the abdomen showed a sharply defined triangular midline longitudinal soft-tissue shadow overlying the pelvis, not typical of bowel pattern or of any shadow normally seen (Fig. 1). The possibility that this was urachus was considered. The outer wall of one loop of small bowel was questionably visualized, but the falciform ligament could not be seen. An additional roentgenogram obtained in erect position confirmed a large pneumoperitoneum (Fig. 2). The patient was noted to have a protuberant lower abdomen, and it was apparently for this reason that air had selectively collected in the lower abdomen in the supine position. At celiotomy, moderate amounts of gas were released as the parietal peritoneum was incised. Bile-stained fluid was aspirated. A small perforation of the anterior wall of the duodenal bulb was identified and repaired. The exploration of the abdomen revealed a deep midline fold anteriorly in its lower part, lined by parietal peritoneum. Its appearance was in keeping with a prominent but normal urachal remnant. The bladder was in normal position. The postoperative course was uneventful. Embryology and Anatomy The cloaca originates from the caudal end of the primitive intestine with eventual differentiation into intestine and urinary bladder (3). The allantoic stalk develops as an endodermal diverticulum from the cloaca, without functional significance except that it accompanies the umbilical arteries which bring the maternal and fetal circulation into communication.

Annular pancreas.

The pancreas develops from ventral and dorsal buds (anlage) each with its own duct originating from the primitive intestine, which at a later stage develops into the second, or descending, portion of the duodenum.¹ The dorsal bud, forming part of the head, the body and the tail of the pancreas, grows toward the spleen. The ventral bud is divided into right and left parts. While the left part atrophies, the right one rotates dorsally and forms the remainder of the head of the pancreas. Failure of rotation of this ventral pancreatic bud together with rotation of the duodenum, results in the encirclement of the second part of the duodenum in its upper two-thirds. Usually the encirclement is complete, but sometimes there is a gap anteriorly. The annular pancreatic tissue usually drains through a duct which passes around the entire duodenum before entering the main pancreatic duct, or it opens

Annular pancreas. Report of case with unusual presenting symptoms and cure.

The term annular denotes a condition whereby a part of the pancreas forms a more or less complete ring around the second portion of the duodenum causing obstruction of varying degree. This entity was first described by Tiedeman in 1818. The condition is not common; about 88 1 cases are described in the literature in patients ranging in age from 2 days to 74 years. 2 The condition may be symptomless, if obstruction is incomplete, and may be found accidentally at autopsy or at surgery when other pathology was suspected. It is important to think of this condition when obstruction occurs high in the gastrointestinal tract in children or when vague epigastric symptoms present themselves in an adult. Embryologically the pancreas develops from two sites, the ventral and dorsal anlagen, each with its duct arising from the primitive intestine which later forms the second portion of the duodenum. 3

DEVELOPMENT OF THE URACHUS.

Early in intrauterine life, the allantois is given off from the posterior end of the primitive intestine; its walls are composed of entoderm and mesoderm provided by the hind end of the primitive groove posterior to the anal membrane. The anal membrane consists of ectoderm and entoderm, i. e., it has no mesodermic tissue. As the anal membrane becomes curled forward to form in conjunction with the lateral infoldings of the embryo the hypogastrium and to contract the umbilical opening, the junction of the intra-embryonal and extra-embryonal portions of the allantois is contracted. A spur of tissue exists between the allantois and the yolk sac or umbilical vesicle. This spur increases and grows backwards through the primitive intestine until it divides the primitive gut into an upper part (intestine) and a lower part, continuous with the allantois, which forms the urinary bladder. Thus the walls of the bladder are formed,