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Biomedical subjects

S Beaudoin

Publications and source records attributed to S Beaudoin.

At least 19 recordsLinked to original sources
PubMed2006

Fetal lung growth in congenital diaphragmatic hernia.

BACKGROUND: In spite of significant therapeutic progress, the prognosis of congenital diaphragmatic hernia (CDH) remains pejorative in those forms in which the liver is herniated into the chest. The severity of this malformation relies on the pulmonary hypoplasia due to lung compression by the herniated viscera in the thoracic cavity, particularly the liver. This impaired growth concerns the whole pulmonary tissue, i.e. both the vessels and the alveoli. For the clinician, it is mandatory to know the evolution pattern of the lesions, to define the best time to treat them. AIM AND METHOD: The aim of this work was to study the pulmonary lesions along the gestation in fetuses affected byCDH. This morphological study was carried out on 134 human fetuses aged from 22 to 40 weeks of gestation. Anatomical and histological analysis focused on lung weight, alveolar count and wall thickness of the distal vessels. RESULTS: The results indicate that the pulmonary lesions worsen as the pregnancy continues, particularly beyond 30 weeks of gestation. CONCLUSION: Such an anatomical study should bring to the clinicians useful data to enhance the management of the patients.

Female↗
PubMed2005

Familial malrotation: report of three affected siblings.

We herein report the case of three siblings presenting with intestinal malrotation. Their medical history and circumstances of diagnosis are described. Barium meal demonstrated a minor duodenal anomaly in the mother. As far as we can ascertain, this is the third report of isolated familial malrotation in more than one generation, raising questions about its developmental mechanism. We thus highlight in what circumstances familial investigations should be undertaken in case of malrotation.

Adult↗
PubMed2004

Pelvic development in the rabbit embryo: implications in the organogenesis of bladder exstrophy.

Current theses of the development of bladder exstrophy and its variants rely on defective evolution of the urinary tract and cloacal membrane. They do not account satisfactorily for the clinical features reported in children affected by exstrophy, especially the pelvic bone anomaly. We herein describe the normal development of the pelvic ring in the rabbit embryo and its chronological relationship with the lower urinary tract organogenesis. Our results suggest that these events are intricated and allow us to propose a novel mechanism to explain exstrophies.

Animals↗
PubMed2004

Uncommon ureteric ectopias: embryological implications.

We herein report two rare ureteric ectopias, one in the uterus, the second in the rectum. These kinds of ectopias are not easily explained with regard to the classic embryological theories of the too-cranial or too-caudal origin of the ureteric bud on the mesonephric duct. We thus set out new explanations consistent with embryological studies on the narrow contact between the developing paramesonephric and mesonephric ducts, and on the so-called cloacal septation.

Choristoma↗
PubMed2001

Worry: daily self-report in clinical and non-clinical populations.

The present study establishes an ecologically-valid point of reference for generalized anxiety disorder (GAD) treatment outcome studies. Although worry is the main diagnostic criterion for GAD, it is also a common and everyday cognition. Few studies have investigated the normal manifestation of worry in a non-clinical population. For this research, time spent worrying and the tendency to worry were measured in a non-clinical sample (n = 36), where GAD was screened-out, and results were compared to those obtained from a GAD sample (n = 60). Participants recorded the time spent worrying in self-monitoring notebooks for two consecutive weeks and completed the French version of the Penn State Worry Questionnaire (PSWQ). It was found that the non-GAD group reported less time spent worrying on a daily basis as well as a lower tendency to worry than the GAD group. Results are discussed in terms of treatment implications.

Adult↗
PubMed2000

Substrate Morphology and Particle Adhesion in Reacting Systems.

This paper describes an effort to measure and model changes in the adhesion of micron-scale particles to substrates in systems in which chemical reactions are occurring. Contact interactions between polystyrene latex spheres and silicon substrates (with surface oxide) immersed in aqueous KNO(3) solutions were studied. Two important results were obtained. First, it was shown that the AFM can be employed to monitor, in situ, changes in adhesive interactions induced by surface chemical reactions in this system. Second, the morphology of the interacting surfaces plays a controlling role in particle adhesion. In particular, for this system, changes in roughness of the substrate changed the interaction force by nearly 90%. Copyright 2000 Academic Press.

Journal Article↗
PubMed2000

Analysis of Contact Interactions between a Rough Deformable Colloid and a Smooth Substrate.

A model was developed for the effect of van der Waals interactions between a rough, deformable, spherical colloid and a flat, smooth, hard surface in contact. The model demonstrates the significant effect of colloid roughness on removal force. Small changes in colloid roughness produce large changes in the predicted removal force. Several authors attribute discrepancies in the observed interaction force between particles and surfaces to colloid roughness, and our model supports their hypotheses. Experimental data documenting the force required to remove colloids of polystyrene latex from silica substrates in aqueous solution were collected during AFM studies of this system. When colloid roughness exists, as is the case in this work, our model bounds the observed removal force. The predicted range of removal forces is in better quantitative agreement with our removal force data than are forces predicted by classical DLVO theory. Copyright 2000 Academic Press.

Journal Article↗
PubMed2000

Anatomical basis of surgical repair of hypospadias by spongioplasty.

Despite the numerous surgical procedures reported for hypospadias repair, little attention has been given to the precise assessment of penile anatomy in this malformation. In this study of 51 cases of hypospadias, we describe the particular anatomy of the corpus spongiosum encountered, highlighting its relationships with the other features observed in the different forms of this anomaly. It appears that the level where the corpus spongiosum diverges into two limbs particularly induces the degree of penile curvature that influences the severity in this malformation. We report a new technique of anatomic repair of the penis in hypospadias.

Follow-Up Studies↗
PubMed1999

A case of malrotation and situs ambiguus.

Isolated levocardia is a rare condition in which intestinal malrotation may be encountered. The case herein reported is particularly uncommon and raises a number of questions about the development of abdominal symmetry.

Child, Preschool↗
PubMed1998

Anatomic study of the umbilical vein and ductus venosus in human fetuses: ultrasound application in prenatal examination of left congenital diaphragmatic hernia.

For clinicians it is very difficult to evaluate the prognosis of a left congenital diaphragmatic hernia (CDH) at prenatal ultrasound examination. Surgical studies show that the presence of a large part of the liver in the chest is a criterion of poor prognosis. However, ultra-sonography encounters some difficulties in determining the precise position of the liver in the thoracic cavity. The aim of this anatomic study was to define the relationship between the position of the liver and the path of the ductus venosus and of the umbilical v., which are easily recognizable at prenatal sonography. Twenty dead fetuses were used for the study (12 with a left CDH and 8 without). All fetuses underwent radiographic assessment, anatomic dissection and cross-sectional study. The angle between the umbilical v. and the ductus venosus in different planes was measured. The more the liver was in the thorax, the greater was the angle between the ductus venosus and the sagittal plane, and the less the angle between the ductus venosus and the umbilical v. These angles can be easily measured by prenatal ultrasound examination of the fetus. Our findings suggest that it is now possible to offer the clinician a new and reliable way to determine the prognosis of a left CDH before birth.

Autopsy↗
PubMed1997

[Hernia in children].

Congenital hernia seems to be the right term to define "hernia in childhood". Especially in newborn and infant, it is possible to observe numerous different pathologies which have nothing in common apart their congenital origin. Some as inguinal or umbilical hernia are very commonly encountered and others us omphalocele, gastroschisis or diaphragmatic hernia are quite rare and involved in the field of prenatal diagnosis and neonatal surgery.

Abdominal Muscles↗
PubMed1997

Anatomical basis of a common embryological origin for epispadias and bladder or cloacal exstrophies.

Epispadias, bladder exstrophy and its variants are in the first place usually considered as urological anomalies. Embryological theses and therapeutic approaches are mainly based upon this aspect. We challenge this point of view, in order to bring out a new axis of research about this still misknown pathologic field. A review of 16 cases of bladder exstrophy, 6 epispadias cases, and one cloacal exstrophy case, which had never been described before, revealed that the almost constant bony defect of the pelvic ring was linked with the severity of the visceral features, and with the continence status in epispadias cases. The commonly admitted theories about exstrophy development are based on a primary defect of the cloacal membrane. We suggest that the first anomaly could lie in a lack of rotation in the pelvic ring primordia.

Bladder Exstrophy↗
PubMed1997

[Surgical approach on rabbit embryos. A model trial of bladder exstrophy].

We describe herein a new model of surgical approach of an early mammalian embryo. Indeed the developmental mechanisms of numerous congenital anomalies, such as bladder exstrophy, remain obscure, and progresses in their knowledge must be achieved to propose better treatments. But up to now all the successful reports in experimental models of early produced malformations concerned birds or batracians, whose development is very different from human. We used the rabbit. Twenty-five time matted does were operated at 12.5 days of gestation. Out of their 247 embryos, 99 underwent a surgical procedure. Forty-eight were injured in order to produce an exstrophy. In 18 cases, the embryo extruded from the uterine cavity and could not be reintegrated, and 2 sacs were found empty. The remaining 31 were only exteriorized. Nine additional does received intravenous teratogen at 12.5 days of gestation. In the group of operated embryos we obtained 6 full-term fetuses, one of whom had a cloacal exstrophy. No exstrophy was noted among the intact embryos, neither in the 87 fetuses submitted to the teratogen. We conclude that: it is possible to operate on an early mammalian embryo, and to obtain further growth until term and that the exstrophy we observed in one case resulted from the surgical specific procedure.

Animals↗
PubMed1995

Gastroesophageal reflux after repair of congenital diaphragmatic hernia.

Seventy-four survivors of congenital diaphragmatic hernia (CDH) repair were reviewed for gastroesophageal reflux (GER). Twenty-nine patients had a prenatal diagnosis of CDH, 31 had the diagnosis established during the first 60 minutes of life, and 14 had a late diagnosis. Fifty-seven of the 60 patients with a prenatal diagnosis or diagnosis at birth had their CDH repaired during the first 24 hours of life. Thirty-six of the 37 patients with clinical signs of GER and 10 patients without typical clinical signs had documented GER. The overall incidence of GER was 62% (46 of 74). The 46 comprised 22 of the 29 patients (75.8%) with a prenatal diagnosis of CDH, 21 of the 31 (67.7%) with a diagnosis at birth, and 3 of the 14 with a late diagnosis. Eleven patients had surgical treatment of GER. A significant correlation was found between GER and the preoperative thoracic position of the stomach (32 v 8, GER+ v GER-; P < .01) and GER and the prenatal diagnosis of CDH (22 v 7, GER+ v GER-; P < .01). Duration of artificial ventilation (68.97 +/- 15.33 days v 14.14 +/- 3.89 days, GER+ v GER-; P < .005) and duration of hospitalization (22.04 +/- 3.59 weeks v 3.9 +/- 0.88 weeks, GER+ v GER-; P < .0003) were significantly longer for the patients with pathological GER. To decrease the morbidity related to GER, we propose using diaphragmatic patches during hernia repair to lower the strain on the crus, and using parietal patches to lower intraabdominal pressure after reintroduction of the herniated viscera.

Female↗
PubMed1995

Gastroesophageal reflux in neonates with congenital abdominal wall defect.

Gastroesophageal reflux (GER), not yet described as a real complication, takes place very often in neonates with congenital abdominal wall defect. Our aim was to determine whether it is due to abdominal hyperpressure alone, or if another factor is involved in this occurrence. Thus we studied one group of 80 gastroschises and one of 67 omphaloceles, treated in our department between December 82 and December 92. Overall occurrence was found to be about 50% in both groups. The main feature is the particular severity of GER in neonates with wide omphalocele who required staged closure, leading to further surgical antireflux procedure. We suggest that this procedure could be performed earlier, at the time of closure, for these babies in whom moreover the anatomic approach is favorable.

Abdominal Muscles↗
PubMedDate not supplied

In utero allotransplantation of retrovirally transduced fetal hepatocytes in primates: feasibility and short-term follow-up.

In utero allotransplantation of fetal hepatocytes into a preimmune fetus could be used in early treatment of many inherited hepatic metabolic diseases. This study was designed to assess the tolerance to hepatocyte transplantation and to test the feasability and toxicity of such an injection in a primate model. Fetal hepatocytes were obtained from two 120-day-old Macaca mulatta fetuses and cryopreserved. They were thawed, cultured in vitro, and transduced with a recombinant retrovirus expressing beta-galactosidase. Transduction efficiency was 75-85%. Three unrelated fetuses (90, 100, and 104 days old) were each given 1-2 x 10(7) transduced cells via the umbilical vein. This caused vasospasm and severe bradycardia. Two fetuses died in the 48 hours after transplantation; the third survived and was killed at the end of gestation. No evidence of the infused cells was found. Three fetuses (90 days old) were, therefore, given 3-4 10(7) hepatocytes by direct intrahepatic injection. All the fetuses survived without side effect. Donor cells were not apparent from histochemical staining and PCR reactions. There was no evidence of inflammatory reaction. These findings indicate that the protocole could be improved by increasing the number of transplanted cells and using specific hepatic promoters in the retroviral vectors to achieve an effective postnatal chimerism.

Animals↗
PubMedDate not supplied

Outcome of 116 moderate renal pelvis dilatations at prenatal ultrasonography.

To determine the incidence of urinary tract abnormalities detected in the presence of moderate fetal renal pelvis dilatation, we followed up pre- and postnatally 116 fetuses and children between 1985 and 1995. At prenatal ultrasound, 50 (43%) fetuses showed regressive dilatations, 57 (49%) a stable pattern, and 9 (8%) an evolutive pattern. In the presence of an evolutive dilatation, urinary tract obstruction was present in 8 cases. When a stable pattern was observed, i.e., a patent uropathy was present, surgical correction was performed in 27 of 53 (51%) cases. Regarding the postnatal evolution of 50 prenatal regressive moderate dilatations, we observed in 12 of 50 (24%) vesicoureteric reflux, of which 5 (10%) required surgical correction, and it is concluded that careful and extensive follow-up is mandatory.

Dilatation, Pathologic↗