Search PubMed⌕ Search

Biomedical subjects

G Pelletier

Publications and source records attributed to G Pelletier.

At least 739 records · Page 41Linked to original sources
PubMedDate not supplied

Management of a case of twin-to-twin transfusion syndrome by a combined surgical approach.

OBJECTIVE: The management of a case of severe twin-to-twin transfusion syndrome at 24 weeks of gestation is presented, using a combined surgical and medical approach. METHODS: Operative fetoscopy was used to coagulate placental vessels crossing the intertwin membranes. Repeated intrauterine transfusions were used to correct recurrent anemia in the donor twin. Selective three-dimensional placental angiography and directed histological analysis were used to study the placenta after delivery. RESULTS: Resolution of twin-to-twin transfusion syndrome was obtained by coagulation of placental anastomoses, but was followed by recurrent anemia in the donor twin. This was successfully treated by serial intrauterine blood transfusions, and 2 healthy twins were delivered at 31 weeks of gestation. One artery-to-vein anastomosis was demonstrated to be the only communication left between the two circulations. CONCLUSIONS: This case illustrates the limitations of placental surgery in twin-to-twin transfusion syndrome and highlights the need for ultrasound and Doppler follow-up of these high-risk fetuses to indicate further treatment. Placental anastomoses can be overlooked by macroscopic examination and injection technique, but can be demonstrated by placental angiography.

Adult↗
PubMedDate not supplied

Stimulus-response incompatibility effects on event-related potentials in children with attention-deficit hyperactivity disorder.

In order to test the hypothesis of a response choice deficit in attention-deficit hyperactivity disorder (ADHD) children, event-related potentials (ERPs) were recorded from 30 scalp electrodes in 21 ADHD and 21 normal boys during a spatial stimulus-response compatibility (SRC) task. ADHD children made fewer correct responses than control children, but did not show a larger incompatibility effect on response speed and accuracy. In ERPs, ADHD children had longer N1 latency and larger condition effect on the frontal N2, which would reflect a greater frontal involvement for the correct responses. The ADHD group who performed the SRC task first showed a larger condition effect on an early occipital P3 only, while the ADHD group who performed the SRC task second showed a larger condition effect on a later central P650 component and on a late parietal NSW, as compared with normal controls. These results suggest strategic differences in information processing in ADHD children, rather than a specific deficit.

Attention Deficit Disorder with Hyperactivity↗
PubMedDate not supplied

ERPs and behavioral inhibition in a Go/No-go task in children with attention-deficit hyperactivity disorder.

In order to study the behavioral responses and the brain inhibition process in children with attention-deficit hyperactivity disorder (ADHD), Event-Related Potentials (ERPs) were recorded from 30 scalp electrodes in 21 ADHD and 21 normal boys during performing a Go/No-go task. ADHD children made fewer correct responses to both Go and No-go stimuli than normal controls. The frontal N2 amplitude was larger for No-go stimuli than Go stimuli in both groups, reflecting inhibition of responding. Smaller N2 amplitudes to No-go stimuli were found in ADHD children, but only when the Go/No-go task was performed after a first stimulus-response compatibility (SRC) task. In addition, the controls exhibited a prolonged N2 only when the Go/No-go task was performed second. However, the ADHD subjects exhibited this prolonged N2 when the task was first, but not when it was second. These results suggest an inhibitory regulation problem rather an inhibition deficit in ADHD children.

Attention Deficit Disorder with Hyperactivity↗
PubMedDate not supplied

[Natural antiallergenic factors in bile].

Two groups of substances having an antihistaminic activity were found on purifying bovine bile. It has already been found that bile acids inhibit contraction of guinea pig ileum; another principle has been isolated which is one thousand times more active than the bile acids; this (these) substance(s)--SAN (" substance antiallergique naturelle ")--seems to have more inhibitory effect on smooth muscle contraction induced by SRSA than histamine, acetylcholine, bradikinin and serotonin. SAN is also able to inhibit the Schultz-Dale reaction. These findings indicate that SAN could be a possible antiallergic agent.

Animals↗
PubMedDate not supplied

Ontogeny of 3 beta-hydroxysteroid dehydrogenase/delta 5-delta 4 isomerase (3 beta-HSD) in human testis as studied by immunocytochemistry.

The enzyme complex 3 beta-hydroxy-5-ene-steroid dehydrogenase/delta 5-delta 4 isomerase (3 beta-HSD) is involved in the biosynthesis of all classes of active steroids, including androgens. To correlate possible changes in 3 beta-HSD with the well-known variations in testosterone secretion during development, the authors localized this enzyme by immunocytochemistry during fetal and postnatal periods of development in the human testis. In the fetal testis, 3 beta-HSD was detected in Leydig cells during the second and third trimester of gestation. In 8-month-old and 11-year-old boys, however, no immunoreaction could be detected in the testis. In pubertal boys, Leydig cells appeared well developed and immunopositive. Since the fluctuations in 3 beta-HSD immunoreactivity are similar to those already observed for androgen secretion, activation of 3 beta-HSD by trophic hormones may play an important role in androgen production during fetal and postnatal development.

Adolescent↗
PubMedDate not supplied

Light and electron microscopical immunolocalization of neuropeptide Y-containing nerves in the hamster gallbladder.

Neuropeptide Y (NPY)-containing nerve structures were detected in the Syrian hamster gallbladder by using peroxidase-antiperoxidase immunohistochemical staining and immunoelectron microscopic techniques. In addition, Alcian blue-P.A.S. was used to differentiate two types of surface cells in the epithelium of the gallbladder: the columnar cells and the tuft cells. NPY-immunoreactive varicose nerve fibers were detected in the adventitial layer of the arterioles, precapillary arterioles and around axial venules of mucosal folds; they were not observed in the capillary beds. Since NPY is associated with norepinephrine (NE) in the sympathetic nerves, it could prolong the adrenergic vasoconstrictive effects. We propose that NPY and NE are simultaneously released to restrict the blood flow in the subepithelial capillary beds by increasing vascular resistance thereby perturbing the absorption of water and electrolytes.

Animals↗
PubMedDate not supplied

[Hepatic and renal toxicity of paracetamol in chronic alcoholic patient].

After taking paracetamol regularly in therapeutic doses, a non-cirrhotic alcoholic subject developed hepatic necrosis and acute renal failure. This case is compared with 13 others found in the literature, and the clinical, biochemical and histological characteristics of such accidents are described. The severity of the acute renal failure is proven by the fact that 50% of the patients had to be put under dialysis. The potentiation of acetaminophen renal and hepatic toxicity by alcohol toxicity is discussed. The principal mechanism of enhancement is the activation of the cytochrome P 450 system associated with depletion of intracellular glutathione.

Acetaminophen↗
PubMedDate not supplied

Ultrasonography, angiography, computed tomography and magnetic resonance in nodular regenerative hyperplasia of the liver: report of a pseudo-tumoral case.

Ultrasonographic, computed tomographic, and angiographic abnormalities of nodular regenerative hyperplasia have been described in very few cases. We report here the case of a 50-year-old man with round, well-limited hypoechogenic lesions involving the two lobes of the liver, and hypervascular, poorly delineated angiographic lesions. Computed tomography and magnetic resonance of the liver were normal. Histological examination of large liver specimens provided by intraoperative biopsy allowed the diagnosis of nodular regenerative hyperplasia. Such a pseudo-tumoral ultrasonographic and angiographic pattern must be recognized in order to avoid diagnostic and therapeutic mistakes, especially since percutaneous liver biopsy usually fails to diagnose this disease.

Biopsy↗
PubMedDate not supplied

Conflict of interest.

Explore the source record for details and available documents.

Conflict, Psychological↗
PubMedDate not supplied

DRG's and home care.

Explore the source record for details and available documents.

Costs and Cost Analysis↗
PubMedDate not supplied

[Hairy cell leukemia. I.--Clinical, biological and evolutive study on twenty-eight cases (author's transl)].

A clinical and laboratory evaluation of 28 patients with hairy cells leukemia is performed. Twenty-two had splenomegaly and all but one had a pancytopenia with 5 to 70% of hairy cells in blood. A tartrate-resistant acid phosphatase activity was positive in the hairy cells of 11 patients of 14 studied. In all patients a myelofibrosis and a leukemic infiltration were found in a bone-marrow biopsy of iliac crest. Hemodilution by splenomegaly, mild hemolysis and dyshematopoiesis were observed in 10 patients by a 51Cr or 59Fe isotopic exploration. In seven cases an immunological study of the hairy cells was performed, a high percentage of the leukemic cells of these 7 patients had polyclonal surface Ig but without resynthesis of monoclonal S Ig which is a feature usually associated with B lymphocytes. In the blood of these patients normal T and B lymphocytes were decreased. A splenectomy was done in 12 patients (43%) always for severe pancytopenia Splenectomy was not randomised. Spleen weights ranged from 1 085 to 3 600 g. In splenectomised patients the level of hemoglobin, segmented cells and thrombocytes was significantly higher after surgery. The survival rate is better in the splenectomised group (median survival 57 months) than in the non-splenectomised group (median survival 19 months). Infectious diseases were frequent in all patients but less after splenectomy. Fourteen patients died, 8 owing to pancytopenia.

Adult↗