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At least 19 recordsLinked to original sources
PubMed1975

Ectopic apudocarcinomas and associated endocrine hyperplasias of the foregut.

Foregut endocrine polypeptide-secreting APUD cells (Amine-Precursor-Uptake and Decarboxylation), in their embryologic migration from neural crest to foregut may become "arrested" in the mesoderm or in other ectopic locations. They may become hyperplastic, adenomatous or malignant. Eight illustrative patients are reported. One patient had "pancreatic hyperparathyroidism" with hypercalcemic crises, pancreatic apudocarcinoma, normal parathyroids, biologically active parathormone, but inert immunochemically to the usual parathyroid antisera. Two had gastrin-secreting malignancies in the mesoderm. Remission after excision, but eventual recurrence of the syndrome due to islet cell hyperplasia required total gastrectomy. One patient had a gastric corpus apudocarcinoma found prospectively with hypergastrinemia which required excision of the tumor. One patient had acromegaly with hypergastrinemia and antral gastrinosis treated by pituitary irradiation, One patient had the antral or intermediary type of the Zollinger-Ellison syndrome with moderate hypergastrinemia, duodenal ulcer and antral gastrinosis, treated by vagotomy and antrectomy. One patient had hyperparathyroidism with antral gastrinosis, treated by parathyroidectomy. One patient had malignant Zollinger-Ellison syndrome and developed associated thyroid parafollicular cell hyperplasia and parathyroid chief cell hyperplasia, treated by total gastrectomy and multiple endocrine excisions. These investigative observations demonstrate ectopic loci and associated hyperplasias which support the concept of migration and bizarre potentiality of polypeptide-secreting cells of the foregut.

Adenoma↗
PubMed1976

Bronchopulmonary foregut malformations. A unifying etiological concept.

Two cases of congenital bronchopulmonary foregut malformation are reported and another 27 cases reviewed and the findings analyzed. The left lower lobe and the entire right lung are the most common locations of pulmonary involvement. The distal portion of the esophagus or cardioesophageal junction was the most common site of communication (83%). The majority of the patients (60%) presented in the first eight months of life, and the incidence in females was nearly twice that in males. Chronic cough, recurrent pneumonias and respiratory distress were the most common clinical findings, whereas two patients were totally asymptomatic. The esophagogram was the single most useful diagnostic procedure (82%). The microscopic structure of the congenital fistula resembled esophagus, bronchus or both. Surgical treatment was curative in most instances. Sime deaths occurred prior to corrective surgery, whereas the postoperative deaths in most instances were related to severe associated congenital anomalies. We believe a common embryologic pathogenesis leads to the formation of a variety of bronchopulmonary foregut malformations. These bronchopulmonary foregut malformations include intralobar and extralobar sequestrations, pulmonary sequestration with patent, or involuted--partial or complete--gastroesophageal communication, esophageal or gastric diverticula, and esophageal or bronchogenic duplication cysts.

Abnormalities, Multiple↗
PubMed1979

[Scanning microscopical observations on the foregut structures o mosquitoes and their role for the ingestion of microfilariae (author's transl)].

Experiments on the transmission of Brugia malayi by various mosquitoes had shown that microfilariae ingested by some species were badly damaged when they reached the stomach, but were much less hurt in others. The structures of the foregut likely to cause these injuries, were investigated and documented by scanning microscope techniques. In Anopheles albimanus, A. arabiensis, A. stephensi and A. pharoensis which have well developed armatures the microfilariae showed a high rate of destruction. In A. stroparvus as well as in Aedes aegypti, Ae. togoi and Culex fatigans in which these structures are missing or poorly developed the larvae were much less affected. From the size, shape and position of the different papillae, spines, rods and cones observed it can be concluded and confirmed that the pharyngeal armature (buccopharyngeal bar) will be by far the most important structure responsible for the injuries of the microfilariae. However, it appears that the characteristics of different filaria species can play an important role in preventing such damages.

Animals↗
PubMed1976

The fine structure of the digestive system of Daphnia pulex (Crustacea: Cladocera).

The alimentary canal of Daphnia pulex consists of a tube-shaped foregut, a midgut (mesenteron) with an anterior pair of small diverticula, and a short hindgut. The foregut and hindgut are structurally similar. Each is formed by a low cuboidal epithelium 5 mum tall and lined with a chitinous intima. The midgut wall consists of a simple epithelium resting on a thick beaded basal lamina which is surrounded by a spiraling muscularis. Anteriorly the midgut cells are columnar in shape being 30 mum in height each having a basal nucleus, anteriorly concentrated mitochondria and in apical border of long thin microvilli. Posteriorly the midgut cells become progressively shorter so that in the posteriormost region of the midgut the cells are 5 mum tall and cuboidal in shape. The microvilli concomitantly become shorter and thicker. All mesenteron cells contain the usual cytoplasmic organelles. The paired digestive diverticula are simple evaginations of the midgut. The wall of each consists of a simple epithelium of cuboidal cells 25 mum in height, each with a brushed border of long thin microvilli. Enzyme secretion appears to be holocrine in mode and not confined to any one region of the mesenteron though definitely polarized anteriorly. The thin gut muscularis encircles the entire length of the midgut and caeca. Thick and thin filaments appear to be in a 6:1 ratio.

Animals↗
PubMed1979

Development of pancreatic endocrine cells in the rat fetus.

Prenatal development of rat pancreatic endocrine cells was investigated by the immunoperoxidase technique and the following results were obtained: 1) Glucagon immunoreactive cells are first endocrine element of the pancreas appearing already on day 11 of gestation, when the dorsal pancreatic bud is still quite small and the ventral pancreatic primordium is hardly swollen out. Most of the glucagon reactive cells are located in the epithelium of the foregut and the dorsal pancreatic bud but a few of them are attached to the base of the epithelium from the outside. 2) Insulin and pancreatic polypeptide (PP) immunoreactive cells are first demonstrable in small cell clusters budding from the exocrine tubules on day 14, whereas somatostatin and gastrin reactive cells on day 17 and 18, respectively. These findings support the hypothesis that the majority of pancreatic endocrine cells is derived from the epithelium of the foregut. 3) PP reactive cells, appearing first on day 14, assume gradually a peripheral position in the growing islet of Langerhans. Immediately before birth they attain the population and flattened cell shape comparable to those in adult pancreas. Their counterpart in the duodenum is found as open type basal-granulated cells in the rat fetus. 4) Noteworthily, glucagon-like immunoreactivity is found in some neuron-like cells of the Auerbach's plexus between the muscle layers of the duodenum on day 19.

Animals↗
PubMed2025

Enhancer remodeling by OTX2 directs specification and patterning of mammalian definitive endoderm.

The molecular mechanisms that drive essential patterning events in the mammalian embryo remain poorly understood. Analysis of transcription factor expression kinetics at peri-gastrulation stages of development suggest Otx2 as a candidate regulator of the definitive endoderm, the precursor of all gut-derived organs. Accordingly, timed OTX2 depletion in gastruloids or during directed differentiation results in abnormal definitive endoderm specification in mouse and human, characterized by altered expression of components and transcriptional targets of the canonical WNT signaling pathway, perturbed adhesion and migration programs, and de-repression of regulators of other lineages. These defects cumulate in impaired foregut formation. Mechanistically, OTX2 is required to activate a subset of endoderm-specific enhancers and to suppress select enhancers of other lineages, allowing timely exit from the primitive streak and correct specification of anterior endoderm. Our results establish OTX2 as an early gut regulator and suggest molecular principles underlying spatiotemporal cell identity conserved across germ layers and species.

Otx Transcription Factors↗
PubMed1977

A reversed jejunal segment interposition as feeding gastrostomy.

Permanent feeding gastrostomies are needed for prolonged alimentation in some patients with foregut obstruction. The usual gastric flap or tube may be limited in patients with previous gastric surgery or with a small stomach. In these patients, interposition of a short, vascularized jejunal segment between the anterior wall of the stomach and the outside may be valuable. Periodic intubation is easy. Tested initially in dogs and then applied to selected patients, we have not seen ulcers, regurgitation, soiling, pain, or other complications.

Animals↗
PubMed1977

Origin, destination and mapping of tritocerebral neurons of locust.

The connectivities of the tritocerebrum of locust (Locusta migratoria L., Schistocerca gregaria (Forsk.)) were studied histologically and by means of cobalt chloride infusion. Its neuropil consists partly of fibers which traverse the tritocerebrum and areas consisting of neuropilar agglomerizations ("glomeruli"). The following direct connections between the tritocerebrum and other regions were observed: connections to 1) dorsal and lateral brain regions (mushroom body, optic lobe), 2) the ventral nerve cord, 3) the stomatogastric nervous system (here the protocerebrum and the subesophageal ganglion are also involved in these connections), 4) the retro-cerebral glands (corpora cardiaca, corpora allata), and 5) muscles of the foregut.

Animals↗
PubMed1976

[Thymic carcinoid. Case report and review of the literature (author's transl)].

A case of a primary thymic carcinoid tumour of a 32 year old male is reported, and the previously published 25 cases are reviewed. The neoplasms occur in adults, predominantly in males: they are located in the anterior or antero-superior mediastinum. The only sufficient treatment is the surgical excision; through radiotherapy may be indicated in some cases, too. The tumour is characterized by the formation of rosettes, ribbons and garlands; sheet-like or medullary areas, and large clusters with central necrosis. The tumour is positive for the Grimelius argyrophil silver stain. Ultrastructurally numerous dense-core "neurosecretory" granules are observed. The formal pathogenesis is similar to that of carcinoid tumours of other locations; particularly of those arriving from derivates of the foregut, respectively from the APUD cell system. At present it cannot be decided whether this particular tumour of the thymus represents an autochthonic thymic carcinoid or simply a teratoma with a differentiation in one direction in the sence of a simplified teratoma.

Adrenocorticotropic Hormone↗
PubMed1976

Nonfunctioning argyrophilic tumor (APUDoma) of the hepatic duct: simplified methods of detecting biogenic amines in tissue.

This report documents a foregut endocrine neoplasm in an unusual location, the main hepatic bile duct, and describes simplified methods of detecting similar endocrine tumors. Formaldehyde fume-induced fluorescence (FIF) is a quick, specific method to demonstrate biogenic amines. FIF combined with histochemical procedures showing abundant alpha-glycerol phosphate dehydrogenase and esterases indicates the neural crest origin of these and related neoplasms. Amine precursor uptake and decarboxylation (APUD) is a significant marker of these cells and gives them their name.

Adult↗
PubMed1975

Sites of organic acid production and pattern of digesta movement in the gastrointestinal tract of geese.

Sixteen geese were used to assess the movement of fluid and particulate digesta through their gastrointestinal tracts and to determine the diurnal variation in organic acid levels for the various segments of the tract. Fluid (polyethylene glycol and chronium-labeled ethylenediaminetetraacetic acid) and particulate markers (2 and 5 mm long) were administered with the meal. Animals were killed at given intervals after the administration of markers. The gastrointestinal tract was divided into nine segments for measurement of markers, pH, volatile fatty acids (VFA), and lactic acid contents. The data indicated a rapid evacuation of fluid marker from the foregut (crop, ventriculus, and proventriculus), while particulate markers were retained for extended periods of time. Retention of fluid marker was observed only within the cecum. Retrograde movement of particulate marker was demonstrated from the duodenum to ventriculus and proventriculus. Retrograde movement of fluid marker was observed from the cloaca to the colon, cecum, and distal third of the small intestine. However, particulate marker showed no retrograde movement in these segments of tract. Highest VFA levels were observed in the cecum. Retention of digesta and production of VFA within the colon were less than those noted for the dog, pig and pony. Lactic acid comprised less than 10% of the organic acids present in the gastrointestinal tract and were at their highest levels in the proximal and mid small intestine.

Animals↗
PubMed1977

Sites of organic acid production and patterns of digesta movement in the gastrointestinal tract of the rock hyrax.

The rock hyrax, smallest of the present day ungulates and a near relative of the elephant, has a gastrointestinal tract of such complex nature that it may be considered ccomparable to both the simple and complex stomach mammals, and also to birds. They have a stomach to body weight capacity equal to that of sheep. But for all its complexity, the passage of ingesta is reasonably rapid. However, there are three major sites of digesta retention and microbial fermentation of the ingested material. The cranial stomach provides the first major site of fermentation with VFA levels comparable to those observed in the rumen (125-145 mM/liter). Quantities of lactic acid are also produced in the foregut where the pH may vary from 2 to 5.5. The ingested particulate material is exclusively retained in the cranial half of the stomach for 4 hours after consumption, and partially retained in the entire stomach for greater than 24 hours. The mid-gut sacculation provides the second major site of fermentation with the retention of the digesta in this gut segment for up to 16 hours. The two ceca provide the third site. Concentrations of VFA in these latter two gut segments approaches 80 mM/liter, while the near stable and neutral pH corresponds to the absence of lactic acid production.

Animals↗
PubMed1979

Leishmania in phlebotomid sandflies. VII. On the taxonomic status of Leishmania peruviana, causative agent of Peruvian 'uta', as indicated by its development in the sandfly, Lutzomyia longipalpis.

The name Leishmania peruviana was given by Velez (1913) to the parasite responsible for a form of cutaneous leishmaniasis known as 'uta'; this disease occurs in the Peruvian Andes. Clinical similarities between uta and 'oriental sore', which is caused by Leishmania tropica of the Eastern Hemisphere, have, however, led to the suggestion that uta is simply due to L. tropica, which was introduced into Latin America by African slaves or European immigrants. Leishmania species are divisible into three distinct sections, according to their pattern of development in their natural (phlebotomine) vectors. One of these sections, the PERIPYLARIA, contains the subspecies of Leishmania braziliensis, and is characterized by parasites that undergo a phase of development attached to the wall of the hindgut (pylorus and ileum), in addition to multiplication in the midgut and subsequent invasion of the foregut. Such development is unknown in any other group of leishmaniae, including those groups of the section SUPRAPYLARIA, which includes parasites of the L. tropica complex. Three isolates of L. peruviana were studied in laboratory-bred sandflies, Lutzomyia longipalpis (Lutz & Neiva), and all showed consistent and prolific development of rounded or stumpy flagellates attached to the wall of the hindgut and, in some instances, growth of free, elongate promastigotes throughout the midgut. Development of both L. tropica and L. major, in the same insect, was restricted to massive development of free flagellates in the midgut, up to the cardial valve. From the behaviour of L. peruviana in the sandfly, its slow growth in hamster skin and the small size of its amastigotes, it is concluded that this parasite is (a) distinctly different from both L. tropica and L. major, and (b) closely related to subspecies of L. braziliensis within the section PERIPYLARIA. On this evidence it is also concluded that L. peruviana is indigenous to the American continent. The specific name is best retained for the time being (rather than L. braziliensis peruviana).

Animals↗
PubMed1976

Neuroendocrine embryology and the APUD concept.

In the Vertebrata the great majority of cells producing hormonal peptides belong to the APUD series and share its distinctive cytochemical and ultrastructural characteristics. According to the concept all members of the series are to be regarded as derivatives of neuroectoderm or of specialized (placodal) ectoderm. For most of the APUD cells this criterion is fulfilled in that their origin from neural tube, neural ridges or neural crest can be considered proven. Complete proof is not yet available for the APUD cells of the gastrointestinal tract and pancreas, and indeed much contrary evidence can be cited. Despite the latter, our embryological studies show: (1) that the hypothalamohypophyseal complex is wholly neuroectodermal; (2)that the chronology of neural crest dispersion is such that this tissue could be responsible for observed APUD cell contributions to the foregut; (3) that placodal ectoderm makes important contributions to pharyngeal pouch endocrine derivatives in birds and mammals; and (4) that the amphibian parathyroid gland is derived from the same layer of neural ectoderm as the hypothalamo-hypophyseal axis. Supporting immunocytochemical studies indicate that peptides belonging to the APUD series are more widely distributed than hitherto recognized and it is concluded: (1) that the whole of peptide endocrinology is neuroendocrinology; and (2) that the APUD cells, with a few cells hitherto regarded as being outside the series, form a third (Endocrine) division of the nervous system to add to the existing Somatic and Autonomic divisions.

APUD Cells↗
PubMed1979

The carcinoid tumour.

Carcinoid tumours are by no means rare. The wide range of sites in which they occur is explained by their origin from APUD cells of the neural crest. These cells migrate to all parts of the alimentary tract during embryonic life, and ultimately are found as well in various gut derivatives such as the respiratory, pancreatic and biliary systems. On the basis of a series of 31 carcinoid tumours seen at the Royal Prince Alfred Hospital in a five-year period, the distinctive clinical and histological features of carcinoids of foregut, midgut and hindgut origin are reviewed. Diagnosis, treatment and results are discussed, and recommendations regarding management of the patient with a carcinoid tumour are given.

Adolescent↗
PubMed1977

The cellular structure of bronchial carcinoids.

A histological and electronmicroscopic study of bronchial carcinoids indicated that these tumours are argyrophilic in keeping with their occurrence in tissue of embryologically foregut origin. Normal bronchi contain cells that resemble, in their electronmicroscopic content, intestinal Kultschitzky-type cells. Characteristic of the carcinoid cell is the presence of intracellular neurosecretory granules seen on electronmicroscopy despite the apparent absence of argentaffin granules under light microscopy.

Bronchial Neoplasms↗