Thirty years' experience of open-repair surgery for pectus excavatum: development of a metal-free procedure.

Objective: Throughout the history of surgery for pectus excavatum (PE), the Nuss procedure and open repair have been performed with many modifications, with most of these procedures using a metal bar. However, the use of a metal bar has several drawbacks. Thus, we aimed to develop a procedure that did not require a metal bar.

Molecular analysis of endoderm regionalization.

We have engaged in a number of studies in our laboratory that have focused on the molecular mechanisms underlying gut formation, with particular attention being paid to the establishment of regional differences found in the entire gut and within each digestive organ. We have found from our analyses that the presumptive fate of the endoderm in the embryos of vertebrates is determined quite early during development, but the realization of this fate often requires molecular cues from the neighboring tissues such as the lateral plate mesoderm and the mesenchyme derived from it. The mesenchyme seems often to exert instructive or supportive induction effects and, in some cases, a completely inhibitory role during the differentiation of the endodermal epithelium.

Distinct roles of presynaptic dopamine receptors in the differential modulation of the intrinsic synapses of medium-spiny neurons in the nucleus accumbens.

Background: In both schizophrenia and addiction, pathological changes in dopamine release appear to induce alterations in the circuitry of the nucleus accumbens that affect coordinated thought and motivation. Dopamine acts principally on medium-spiny GABA neurons, which comprise 95% of accumbens neurons and give rise to the majority of inhibitory synapses in the nucleus. To examine dopamine action at single medium-spiny neuron synapses, we imaged Ca2+ levels in their presynaptic varicosities in the acute brain slice using two-photon microscopy.

Adenovirus-mediated WGA gene delivery for transsynaptic labeling of mouse olfactory pathways.

Detailed knowledge of neuronal connectivity patterns is indispensable for studies of various aspects of brain functions. We previously established a genetic strategy for visualization of multisynaptic neural pathways by expressing wheat germ agglutinin (WGA) transgene under the control of neuron type-specific promoter elements in transgenic mice and Drosophila. In this paper, we have developed a WGA-expressing recombinant adenoviral vector system and applied it for analysis of the olfactory system.

Demonstration of sucrase immunoreactivity of the brush border induced by duodenal mesenchyme in chick stomach endoderm.

When stomach endoderm of chick embryos was recombined and cultured with duodenal mesenchyme, the endoderm developed a brush border structure over a large area and also differentiated into mucous cells in a small area according to its own developmental fate. In the present investigation, we examined whether the induced brush border structure expressed sucrase antigen by immunoelectron microscopy using the antiserum raised against chicken sucrase. Sucrase immunoreactivity could be detected as ferritin particles in the region where the brush border was induced, whereas it was never detected on microvilli of endodermal cells which differentiated into the mucous cells.

Analysis of Epithelial Protein Profiles of Prostatic Glands Induced Heterotypically in the Bladder Epithelium of the Rat: (mesenchymal-epithelial interaction/prostate-specific/heterotypic differentiation/urinary bladder/urogenital sinus).

When urinary bladder epithelia of rats were grown in association with fetal urogenital sinus mesenchyme, prostatic morphogenesis was induced. The epithelial proteins were examined by HPLC fractionation followed by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE). More than 500 bands of silver-stained epithelial proteins were analyzed.

Heterotypic induction of stomach-like glands in the urogenital sinus endoderm under the influence of stomach mesenchyme of foetal rats.

Urogenital sinus endoderm of 16.5-day rat foetuses was combined with stomach mesenchyme and the recombinants were either treated with testosterone and grown in vitro or cultured beneath the kidney capsule of adult male rats of the same strain. It was found that testosterone stimulated mitosis in the urogenital endoderm.

Epithelial Metaplasia Induced Amnionic Ectoderm by the Dermis of Chicken Embryos : (mesenchymal-epithelial interaction/feather/scale/skin/keratin).

Amnionic ectoderm of 6.8-day chicken embryos was associated with 6.8-day dorsal dermis or 13-15-day scale dermis and cultured on host chorio-allantoic membrane for 8 days.

Pepsinogen Induction in Chick Stomach Epithelia by Reaggregated Proventricular Mesenchymal Cells In Vitro: (stomach/organ culture/pepsinogen/induction/epithelial-mesenchymal interaction).

In vitro organ culture system which permits embryonic chick proventriculus (glandular stomach) to synthesize pepsinogen de novo was developed. Explants of the proventricular rudiment were cultured on Millipore filters in Medium 199 with Earle's salts supplemented with 50% 12-day embryo extract at 38°C in 95% air and 5% CO . In these culture conditions, pepsinogen, a functional marker protein of proventriculus, was first detected after 3 days of cultivation of 6-day chick proventricular rudiment.

Developmental changes in the ability to express embryonic pepsinogen in the stomach epithelia of chick embryos.

The avian stomach is subdivided into two parts, the proventriculus and the gizzard. It has been shown that the gizzard epithelium can express embryonic chick pepsinogen (ECPg) antigen, a marker protein of the proventricular epithelium, as well as normal proventricular epithelium, under the appropriate experimental conditions. To study the possible mechanisms involved in the suppression of ECPg synthesis in the gizzard epithelium during normal development, we carried out heterotypic and heterochronic recombination experiments of the epithelium and mesenchyme of these two organ rudiments.

Immunological Relationships among Embryonic and Adult Chicken Pepsinogens: A Study with Monoclonal and Polyclonal Antibodies: (chicken pepsinogens/development/antibodies/immunocytochemistry/immunoblotting).

To investigate the immunological relationships of pepsinogen isozymes present in embryonic and adult chicken proventriculi, we obtained monoclonal and polyclonal antibodies to these pepsinogens. Zymograms and immunoblots demonstrated that monoclonal antibody Y37 reacted with both embryonic and slow-migrating adult pepsinogens, while polyclonal antibodies against embryonic pepsinogen and fast-migrating adult pepsinogen were specific for these respective antigens. Shift from embryonic to adult-type pepsinogen occurred at about the time of hatching and the localizations of embryonic and adult-type pepsinogens within proventricular gland cells were found to differ by the indirect immunofluorescence method.

Gizzard epithelium of chick embryos can express embryonic pepsinogen antigen, a marker protein of proventriculus.

The avian stomach is composed of two distinct organs, the proventriculus and the gizzard. Pepsinogen expression in the proventricular and gizzard epithelia of chick embryos was investigated immunohistochemically with anti-embryonic chick pepsinogen (anti-ECPg) antiserum. In normal development, the ECPg antigen was expressed only in the glandular epithelial cells of the embryonic proventriculus from the 8th day of incubation onwards.

Histogenesis of the Os Penis and Os Clitoridis in Rats: (chondrogenesis/bone formation/testosterone/genital tubercle).

The development of the os penis in normal male rats and the os clitoridis in the females treated with testosterone were studied histologically and histochemically. Alcian blue-positive materials, alkaline phosphatase activities and calcium deposit were detected. The os penis of the rats was composed of a proximal segment and a distal one.

DIFFERENTIATION OF THE DIGESTIVE TRACT EPITHELIUM UNDER THE INFLUENCE OF THE HETEROLOGOUS MESENCHYME OF THE DIGESTIVE TRACT IN THE BIRD EMBRYOS.

The endoderm of the oesophagus, proventriculus, gizzard or small intestine of the 5-day-old chick or quail embryo was cultivated in combination with homologous or heterologous mesenchyme on a WxxxOLFFyyy and HxxxAFFHNyyy medium for 7 to 21 days or on the chorio-allantoic membrane (CAM) for 8 days. With homologous mesenchyme the epithelium always differentiated homotypically. In association with heterologous mesenchyme, the differentiation of the epithelium was both homotypical and heterotypical depending on the region of the digestive tract.

Heterotypic differentiation of chick allantoic endoderm under the influence of various mesenchymes of the digestive tract.

Dissociation and reassociation experimentsin vitro were carried out to investigate the differentiation potency of chick allantoic endoderm under the influence of digestive tract mesenchymes. 1. The allantoic endoderm, when cultured alonein vitro, shows no differentiation whatsoever.