Is the pterygopalatomaxillary suture (sutura sphenomaxillaris) a growing suture in the fetus?

The pterygopalatomaxillary suture is considered as having an important role in the posteroanterior growing of the maxilla. To determine whether this suture is a growing suture in the fetus, we performed a histological study of this suture in a fetus aged of 16 weeks of amenorrhea. Serial sections (5 microm) of the pterygopalatomaxillary suture area have been performed.

Treatment with dehydroepiandrosterone sulfate increases NMDA receptors in hippocampus and cortex.

Our aim was to investigate if the memory-enhancing effects reported for dehydroepiandrosterone sulfate in rodents could be mediated through modulation of NMDA receptors. Using autoradiography we studied the effect of dehydroepiandrosterone sulfate, administered for 5 days (30 mg/kg, i.p.

[The growth of the maxilla in humans. What place for the premaxilla?].

Introduction: The growth of the maxilla in man is still debated. Many authors described an anterior part of the maxillary bone, called premaxilla distinct from the maxilla proper. This description referred to the existence in animals of an incisive or premaxillary bone which does not exist in man.

[Appearance of the branchial system in cervicofacial embryology].

The aortic arch, vascular component of the branchial segment, is considered as its determining element. This is only justified in the conception of a branchial primordium, although this has now been discarded. The direct objections against this theory of a vascular preeminence are presented.

[Human cervico-facial morphogenesis. Evaluation of acquired data and current outlook. Second part: cervical morphogenesis].

After having recalled the formation of the so-called "branchial" organisation, each component of the segmentary units constituting this organisation is analysed, as well as their particularities. This lead us to recognize the existence of only five branchial arches in the human embryo, without an intermediary arch between the fourth arch and the pulmonary arch. This question is moreover linked to the signification of the so-called "ultimobranchial" body, which must be connected with the fourth pharyngeal pouch.

[Human cervico-facial morphogenesis. Evaluation of acquired data and current outlook. (Part 1: facial morphogenesis)].

The embryonic development of the face has been studied in many reviews, this work purposes only to clear up some points which remain obscure concerning cervico-facial morphogenesis. In the first part of this study only the facial development, properly speaking, is considered, although it cannot be separate of cervical development to which a second study will be reserved. In the present study we recall the particular aspects of the neurulation in the cephalic area, then the establishment of the facial processes.

[Degeneration and regeneration of striated skeletal muscle fibers in Duchenne muscular dystrophy].

Like all other muscular dystrophies, Duchenne muscular dystrophy is characterized by the coexistence of degenerative lesions of the muscle fibers and of regenerative changes. The present study has been carried out in order to precise the degree of regeneration at different stages of the disease, by analyzing the expression of several markers of cell proliferation and of muscular differentiation. In the two affected foetuses of our series, the m.

Developmental expression of transforming growth factor-alpha in the upper digestive tract and pancreas of the rat.

This study was designed to examine the developmental expression and the localization of the transforming growth factor alpha (TGF-alpha) in the upper gastrointestinal tract and pancreas of the rat. Immunohistochemical techniques using an antibody against rat TGF-alpha were performed on the stomach, duodenum and pancreas of fetuses (19 to 21 days of gestation), of pups during the suckling period (days 0 to 13 postpartum) and after weaning (day 25 postpartum) and of adults. The temporal appearance of TGF alpha varied depending on the tissues.

[Aspects of facial morphogenesis in the rat].

The facial morphogenesis of the rat has been observed by scanning microscopy on embryos taken every day from the 10th post-coitum day to term. Three points should be noted. Firstly the muzzle has at the beginning of the development an individuality which tends to diminish later.

Growth pattern of the polypeptide-YY cell population in the upper digestive tract of the rat during the perinatal period and after weaning.

The distribution of polypeptide-YY cells within the gastric and duodenal mucosa of the rat and the development of their populations were examined daily from 3 days before birth until day 8 postpartum and after weaning, on day 25 postpartum, using a precise technique of quantification. Polypeptide-YY cells appeared in the stomach around the 19th day of gestation. They were always more numerous in the antral mucosa and particularly in the pyloric sphincter area than in the fundic mucosa.

Comparative development of gastrin and somatostatin cell populations in the pancreas, stomach, and duodenum of the rat during the perinatal period.

The comparative growth patterns of endocrine gastrin and somatostatin cell populations were examined in the rat, during the perinatal period, to investigate possible relationships between their development and that of gastric acid secretion, gastrin and somatostatin hormones being implicated in the regulation of acid secretion. Total cell populations were estimated daily in the pancreas, stomach, and duodenum, by using a quantitative morphological method, from 19 days postcoitum to 8 days postpartum. In the pancreas, both cell types were present at 19 days postcoitum.

Biphasic development of pentagastrin sensitivity in rat stomach.

Rat stomach sensitivity to pentagastrin was examined in fetal (days 19--21) and newborn (5--day-old) preparations in vivo and in vitro. Gastric acidification in vivo was expressed as the gastric content pH and in vitro as the net transepithelial H+ fluxes determined in an Ussing chamber. In both preparations, fetal stomach first responded to pentagastrin on day 20.

Acid secretion in fetal rat stomach in vitro.

In vivo fetal rat stomach produces HCl 48 h before birth. This study examines the mechanisms of H+ secretion from days 19 to 21 before birth. Isolated fetal stomachs were mounted as flat sheets in Ussing chambers for measurement of the transepithelial H+ fluxes (JH+) and short-circuit current (Isc), as indexes of the active ionic fluxes, and for measurement of total ionic conductance (G) and unidirectional mannitol fluxes from serosa to mucosa (JMans leads to m), as indexes of passive permeability.