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Biomedical subjects

A Breton

Publications and source records attributed to A Breton.

At least 19 recordsLinked to original sources
PubMed2000

Protein kinase C-alpha participates in FcgammaR-mediated phagocytosis in macrophages.

Phagocytosis of IgG-opsonized particles by macrophages requires the activation of protein kinase C (PKC), a family of protein serine/threonine kinases. In the present study, we have investigated the role of the PKC-alpha isoenzyme in FcgammaR-mediated phagocytosis using clones of the mouse macrophage cell line RAW 264. 7 overexpressing a dominant-negative (DN) mutant of PKC-alpha. Overexpression of DN PKC-alpha had no effect on the attachment of IgG-opsonized sheep red blood cells, but inhibited their internalization. Further analysis of the signaling events induced by IgG-opsonized sheep red blood cells revealed that whereas tyrosine phosphorylation of Syk was normal, phosphorylation of ERK 1/2 (p42/44) was impaired in DN PKC-alpha-overexpressing macrophages. These observations suggest a role for PKC-alpha in the regulation of FcgammaR-induced phagocytosis and signal transduction.

Animals↗
PubMed1999

Chronic intestinal pseudoobstruction syndrome: clinical analysis, outcome, and prognosis in 105 children. French-Speaking Group of Pediatric Gastroenterology.

Our aim was to collect a large number of cases to characterize clinical presentation, outcome, and prognosis of chronic intestinal pseusoobstruction in children. We conducted a retrospective multicenter study that included children treated for chronic intestinal pseusoobstruction defined as recurrent episodes of intestinal obstruction with no mechanical obstruction, excluding Hirschsprung's disease. In all, 105 children, 57 boys and 48 girls, were studied, including five familial forms. Prenatal diagnosis was made in 18 patients. Eighty patients were less than 12 months old at onset; the disease began at birth for 37 patients. The most frequent signs were abdominal distension, vomiting, and constipation. Megacystis was noted in myopathies (7 cases), neuropathies (10 cases) and unclassified forms (13 cases). For all but three cases (two patients with CMV infection, one with Munchhausen-by-proxy syndrome), the associated diseases and disorders could not account for chronic intestinal pseusoobstruction as a secondary disorder. At least one full-thickness biopsy from the digestive tract was studied for 99 patients. The diagnosis recorded was visceral neuropathy in 58 cases, visceral myopathy in 17 cases, and uncertain or normal biopsy results in 24 cases. Seventy-eight children were fed intravenously, and only 18 were able to be fed orally throughout their illness. Seventy-one patients underwent surgery during their illness, and 217 surgical procedures, a mean of 3 per patient, were performed. Ostomy was the most performed procedure. Follow-up continued in 89 patients for 3 months to 16 years (mean 85 months). Forty-two patients were still fed by parenteral (39 patients) or enteral nutrition (3 patients) at the time of the study. Eleven patients died between the age of 1 month and 14 years 7 months.

Age of Onset↗
PubMed1998

[Food allergies and intolerances in children].

Allergies and food intolerance together comprise the manifestations of "adverse food reaction". The best known and most common are: allergy to cow's milk proteins (prevalence 0.5% to 7.5%), intolerance to lactose (prevalence after weaning 5 to 100%) and gluten intolerance (prevalence 0.5%). Treatment of these conditions is based on management of the diet by exclusion (or reduction) of the responsible food or antigen.

Celiac Disease↗
PubMed1998

[Pseudo-periodic disease with hyperimmunoglobulinemia D: a never-ending story with probable prenatal onset].

UNLABELLED: Diagnosis of inflammatory non-infectious diseases with a neonatal onset is often retrospective. It may lead to aggressive and iatrogenic procedures. PATIENT: A 6-year-old boy was suffering, since birth, from recurrent febrile attacks including rashes, gastrointestinal manifestations and inflammatory joint involvement. This syndrome, partially improved with steroids, could have been of antenatal onset. Since the age of 4 years, the patient is considered as having hyper-IgD syndrome (HIDS). DISCUSSION: HIDS must be distinguished from familial Mediterranean fever. Patients suffer from recurrent fever concomitant to inflammatory joint involvement, abdominal distress, skin lesions, swollen lymph nodes and hepatosplenomegaly (especially seen in children). All patients have high serum IgD (> 100 UI/mL) and IgA levels. Nevertheless, a high IgD level is not specific. Our case could also be part of the CINCA (chronic, infantile, neurological, cutaneous and articular) syndrome, which includes similar early manifestations associated with a constant neurological and frequent ophthalmological involvement and epiphyseal changes; to date, these last three manifestations are not present in our patient. CONCLUSION: HIDS and CINCA syndrome are not known to be modified by any effective therapeutic agent. When presenting at birth, these inflammatory diseases must be considered as entities with a rarely described potential severity.

Anti-Inflammatory Agents↗
PubMed1997

Antineutrophil cytoplasmic antibodies in children with inflammatory bowel disease: prevalence and diagnostic value.

BACKGROUND: Antineutrophil cytoplasmic antibodies (ANCA), particularly perinuclear ANCA (p-ANCA), have been found more frequently in sera from patients with ulcerative colitis (UC) than in sera from Crohn's disease (CD) or unclassified enterocolitis (UE) patients. This 2-center study examined sera from 102 pediatric patients with inflammatory bowel disease (IBD) to evaluate their diagnostic value and assess their relationship with disease features, distribution, activity and treatment. METHODS: The serum ANCA of 102 children with IBD were measured: 33 UC, 64 CD and 5 UE with various disease locations and degrees of activity. The mean age at the onset of symptoms was 10.7 years (1 to 16.3 years). Sera from 26 unaffected first degree relatives and 20 children without IBD were also investigated. ANCA were detected using indirect immunofluorescence of ethanol-fixed granulocytes. RESULTS: There were ANCA in the sera of 24/33 children with UC (73%), 9/64 with CD (14%) and 4/5 with UE (80%). p-ANCA were more frequent than cytoplasmic-ANCA in positive sera: UC = 67%, CD = 57% and UE = 75%. The presence of ANCA was 73% sensitive and 81% specific for a diagnosis of UC, compared to other IBD (p < 0.001). Three children with proved sclerosing cholangitis associated with UC were all positive. There was no link between ANCA-positive sera and disease activity, or other endoscopic or clinical criteria. ANCA were detected in 4/26 first degree relatives (15%) and in 1/20 control subjects (5%). CONCLUSIONS: Because of their sensitivity and specificity, ANCA may be helpful in the clinical assessment of patients with IBD, and especially those with UC. However, there is no link between the pressure of p-ANCA and the site of UC or its activity, so that it cannot be used to monitor medical treatment or surgical indications.

Adolescent↗
PubMed1996

Glycoside and polysaccharide hydrolase activity of the rumen anaerobic fungus Caecomyces communis (Sphaeromonas communis SENSU ORPIN) at early and final stages of the developmental cycle.

The rumen anaerobic fungus Caecomyces communis was grown in a fermentor in Lowe medium. We studied four polysaccharide hydrolases and three glycoside hydrolases at early and final stages. We found a difference in cell association for these enzymes depending on the developmental stage. The endocellulase and beta-D-fucosidase were early synthesized, and their activities decreased at the end of the developmental cycle. On the contrary, the beta-D-glucosidase, beta-D-xylosidase and xylanase activities increased during the cycle. The avicelase and the CM-cellulase activities linked with thalli increased, whereas the extracellular activities of these enzymes decreased.

Animals↗
PubMed1996

Polysaccharide hydrolase production by the rumen fungus Caecomyces communis.

The anaerobic fungus Caecomyces communis was grown in a fermentor in either a discontinuous cultivation system or in a culture system with daily withdrawal and addition of fresh medium. Lowe and Orpin media were tested. The Lowe medium was best for the stimulation of enzyme production, the Orpin medium, for the stimulation of fungal growth and enzyme release. Xylanase activity was predominant among the polysaccharide hydrolases. Most of the enzymes studied were associated with cells except when the culture medium contained glucose or Ray grass hay. Enzymatic activities were constitutive, but their level was regulated by a carbon source. Cellulase production in both the cellular and extracellular fractions and the extracellular xylanase activity were stimulated by the presence of glucose. Cell-associated xylanase activity, however, was stimulated by glucose plus cellobiose. The presence of glucose enhanced enzyme release.

Animals↗
PubMed1995

Location by fluorescence microscopy of glycosidases and a xylanase in the anaerobic gut fungi Caecomyces communis, Neocallimastix frontalis, and Piromyces rhizinflata.

beta-D-Glucosidase, beta-D-fucosidase, beta-D-xylosidase, and beta-D-cellobiopyranosidase activities in Caecomyces communis, Neocallimastix frontalis, and Piromyces rhizinflata, located with fluorescent conjugates, occur throughout the whole thallus as from zoospore germination and disappear before sporulation. beta-D-Galactosidase and alpha-L-arabinopyranosidase activities are low or nonexistent. A xylanase, detected by indirect immunofluorescence, was observed at the surface of the vegetative cells, vesicles, or rhizoids. Cross-reactions prove the existence of analogies in structure among the enzymes of these anaerobic gut fungi.

Animals↗
PubMed1995

[Bone abnormalities and fetal cytomegalovirus infection].

BACKGROUND: Viruses, such as those of congenital rubella and cytomegalovirus infection, have been associated with bone lesions of rarefaction. CASE REPORT: A full-term neonate was admitted at bith (birth weight: 1,630 mg; head circumference: 29 cm) for hypotrophy. A severe growth retardation had been diagnosed at 32 weeks of gestation. The fetal karyotype was normal. Search for maternal toxoplasmosis, syphilis and rubella was negative. The neonate had a complex heart defect; skeletal X-ray films showed metaphyseal transverse bands of rarefaction of the long bones and longitudinally streaked band of sclerosis and rarefaction at the ends of the femora. Urine culture was highly positive for CMV while CMV IgM were negative and CMV IgG highly positive in serum. CONCLUSIONS: Neonatal bone changes usually seen in congenital rubella infection may also be observed in CMV infection.

Bone and Bones↗
PubMed1991

DNA of some anaerobic rumen fungi: G + C content determination.

The nuclear DNAs from five species of anaerobic rumen fungi have been isolated and purified by means of two extraction methods (with and without 8 M urea). Their G + C contents have been characterized by the thermal denaturation procedure of Marmur and Doty. As has already been shown in Neocallimastix frontalis, the results obtained by the two techniques demonstrated a very low G + C content (less than 20%) and the constant presence of satellite DNA.

Animals↗
PubMed1991

Piromyces rhizinflata nov. sp., a strictly anaerobic fungus from faeces of the Saharian ass: a morphological, metabolic and ultrastructural study.

A new species of strictly anaerobic chytridiomycete was isolated from dried faeces of the Saharian ass that had been stored for up to 150 days. Because of its monocentric thallus and uniflagellate zoospores it belongs to the genus Piromyces. It exhibits a high affinity for P. mae and P. dumbonica but differs from them in its morphological and ultrastructural characteristics. Its flagellar apparatus is similar to that of all previously reported fungi.

Animals↗
PubMed1990

Use of lectins for a comparative study of cell wall composition of different anaerobic rumen fungal strains.

The technique based on fluorescein-linked lectins used to determine the cell wall structure of anaerobic rumen fungi belonging to genera: Neocallimastix, Piromonas and Sphaeromonas, appears to be an interesting tool for distinguishing between strains. Furthermore this technique shows differences of cell wall composition between different parts of the thallus (spores, sporangia, rhizoïds).

Anaerobiosis↗
PubMed1990

Anaeromyces mucronatus nov. gen., nov. sp. A new strictly anaerobic rumen fungus with polycentric thallus.

A new species of strictly anaerobic fungus was isolated from the cow rumen. It is characterized by a polycentric thallus, a polynuclear rhizomycelium, mucronate zoosporangia and uniflagellated zoospores. It is also singular in that the sporocysts do not react to the specific lectins of L-fucose, N-acetyl-D-galactosamine and diacetyl chitobiose. These characteristics justify the creation of a new genus.

Anaerobiosis↗
PubMed1989

Acute monocytic leukemia with B cell markers expression following B chronic lymphocytic leukemia.

A case of chronic lymphocytic leukemia (CLL) treated with chlorambucil, followed by the development of an acute monoblastic leukemia, is described. Cytofluorometric quantitative immunophenotype was determined during the blastic phase. Whereas small lymphocytes displayed a CD19+; CD24+; CD37+; CD5+ phenotype, the blastic population exhibited, besides CD13, CD14 and CD15 positivity, which is usually noted in such a monoblastic leukemia, definite CD9, CD10, CD22, CD24, CD37, CD5 and CD4 staining. Such results argue against a complete independence between the two clones, although their similarity could not be demonstrated.

Aged↗
PubMed1987

Keratitis, ichthyosis, and deafness (KID) syndrome. Vertical transmission and death from multiple squamous cell carcinomas.

A father and daughter had typical clinical features of the keratitis, ichthyosis, and deafness (KID) syndrome, as described by Skinner et al in 1981. To our knowledge, ours is the first observation of a vertical transmission of this syndrome. The mechanism of inheritance is uncertain. These two patients as well as the 26 previously described exhibited a typical hyperkeratotic eruption, which should not be confused with ichthyosis. The characteristic features are diffuse hyperkeratosis, keratotic plaques, reticulated hyperkeratosis on the face, peribuccal grooves, and heavy-grain leatherlike keratoderma. The occurrence of multiple squamous cell carcinomas underlines the seriousness of this congenital ectodermal defect. Etretinate can relieve the lesions without actually improving the chances of survival.

Adult↗