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Biomedical subjects

A Petit

Publications and source records attributed to A Petit.

At least 91 records · Page 5Linked to original sources
PubMed1993

Pili torti with congenital deafness (Bjornstad's syndrome)--report of three cases in one family, suggesting autosomal dominant transmission.

Pili torti is a rare hair shaft abnormality in which the hair is flattened and intervals twisted at irregular through 180 degrees about its axis. Pili torti may occur as a congenital defect or as an acquired disorder (secondary to patchy alopecia from a variety of causes). When it is congenital, it may be isolated and determined by an autosomal dominant gene or associated with various rare syndromes, including ectodermal dysplasias, neurological defects and metabolic disturbances. The association of neurosensory hearing loss and pili torti has been recognized as Bjornstad's syndrome since 1965. As far as we know, only 15 cases of this syndrome have been reported. We describe here three cases of Bjornstad's syndrome in one family.

Adolescent↗
PubMed1993

Correlative Association between Resident Plasmids and the Host Chromosome in a Diverse Agrobacterium Soil Population.

Soil samples collected from a fallow field which had not been cultivated for 5 years harbored a population of Agrobacterium spp. estimated at 3 x 10 CFU/g. Characterization of 72 strains selected from four different isolation media showed the presence of biovar 1 (56%) and bv. 2 (44%) strains. Pathogenicity assays on five different test plants revealed a high proportion (33%) of tumorigenic strains in the resident population. All tumorigenic strains belonged to bv. 1. Differentiation of the strains by restriction fragment length polymorphism analysis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis of cellular proteins, and utilization patterns of 95 carbon substrates (Biolog GN microplate) revealed a diversified bv. 1 population, composed of five distinct chromosomal backgrounds (chr A, C, D, E, and F), and a homogeneous bv. 2 population (chr B). chr A, B, C, and D were detected at similar levels throughout the study site. According to opine metabolism, pathogenicity, and agrocin sensitivity, chr A strains carried a nopaline Ti plasmid (pTi), whereas chr C strains had an octopine pTi. In addition, four of six nontumorigenic bv. 1 strains (two chr D, one chr E, and one chr F) had distinct and unusual opine catabolism patterns. chr B (bv. 2) strains were nonpathogenic and catabolized nopaline. Although agrocin sensitivity is a pTi-borne trait, 14 chr B strains were sensitive to agrocin 84, apparently harboring a defective nopaline pTi similar to pAtK84b. The other two chr B strains were agrocin resistant. The present analysis of chromosomal and plasmid phenotypes suggests that in this Agrobacterium soil population, there is a preferential association between the resident plasmids and their bacterial host.

Journal Article↗
PubMed1993

Subcutaneous emphysema and pneumomediastinum following dental extraction.

A case of acute subcutaneous emphysema of the lateral region of the neck is described. The patient, a 26-year-old woman, also had radiologic evidence of pneumomediastinum. She completely recovered in a few days under prophylactic antibiotherapy. In this case, subcutaneous and mediastinal emphysema was most probably due to the introduction of air into the soft tissue during dental surgery using compressed air equipment.

Adult↗
PubMed1993

A role for extracellular calcium in the regulation of placental lactogen release by angiotensin-II and dopamine in human term trophoblastic cells.

We previously reported that angiotensin-II (AII) stimulated and dopamine (DA) inhibited the release of human placental lactogen (hPL) from trophoblastic cells. The mechanisms of action involved in these endocrine regulations are poorly known. In this study, we investigated the role of Ca2+ as a potential cellular mediator of the effects of AII and DA. Incubation of freshly isolated human term trophoblastic cells with DA led to a dose-dependent inhibition of 45Ca2+ influx, with a maximum of 55 +/- 5% and an EC50 of 10 +/- 3 mumol/L. This DA-inhibited Ca2+ influx was reversed by spiperone, a D2-dopamine receptor antagonist. Preincubation of cells with pertussis toxin completely blocked the inhibitory effect of DA on placental 45Ca2+ influx. Nifedipine (10(-5) mol/L), like DA, inhibited 45Ca2+ influx (41 +/- 3% inhibition). Moreover, nifedipine decreased hPL release (57 +/- 10%; EC50, 0.25 +/- 0.09 mumol/L). Coincubation of DA and nifedipine did not enhance the inhibitory effects of these agents on either 45Ca2+ influx or hPL release. The incubation of trophoblastic cells with [Sar1]AII, a potent agonist of AII, led to a dose-dependent stimulation of 45Ca2+ influx. The maximal stimulation was 221 +/- 37% of the control value, with an EC50 of 50 +/- 15 nmol/L. This stimulation was inhibited by coincubation with the AII antagonist [Sar1,Ala8]AII. [Sar1]AII-stimulated Ca2+ influx was blocked by preincubation with pertussis toxin. Bay K 8644 also stimulated 45Ca2+ influx (238 +/- 41% of the control). Moreover, Bay K 8644 stimulated hPL release. The maximal stimulation was 180 +/- 22% of the control value, with an EC50 of 0.40 +/- 0.30 mumol/L. Coincubation of Bay K 8644 and AII did not led to additional stimulation of either 45Ca2+ influx or hPL release. These results suggest that Ca2+ influx is one mechanism that mediates AII and DA regulation of hPL release in human term trophoblastic cells.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed1993

[Squamous erythema annulare centrifugum].

A case of squamous erythema annulare centrifugum has been observed. It was characterized by striking clinical features and peculiar histological findings, including necrosis of keratinocytes. A search for causative factors was negative. Treatment with tar ointment (Brocq) rapidly resulted in dramatic healing of the lesions; however, the usual features of annular psoriasis were absent in our case.

Erythema↗
PubMed1992

Does high level production of SHV-type penicillinase confer resistance to ceftazidime in Enterobacteriaceae?

We report the isolation of a clinical isolate of Klebsiella pneumoniae that showed resistance to ceftazidime (MIC: 8 micrograms/ml), susceptibility to aztreonam (MIC: 2 micrograms/ml) and cefotaxime (MIC: 0.015 micrograms/ml). A synergistic effect between clavulanic acid and ceftazidime or aztreonam against this strain was also observed. The strain hyperproduced SHV-1 penicillinase (990 U/g) which is encoded by a self-transferrable plasmid of at least 150 kb. That the ceftazidime-resistance phenotype could be due to hyperproduction of SHV-1 penicillinase is supported by the study of a spontaneous ceftazidime-resistant mutant in vitro obtained from an Escherichia coli strain containing plasmid p453 encoding the SHV-1. Indeed, this mutant hyperproducing SHV-1 (2200 U/g) was resistant to ceftazidime (MIC: 16 micrograms/ml) and aztreonam (MIC: 8 micrograms/ml) but susceptible to cefotaxime (MIC: 0.03 ng/ml). Clavulanic acid showed a synergistic effect when associated with ceftazidime or aztreonam. In contrast, the hyperproduction of TEM-1 (790 U/g) did not confer a ceftazidime- and aztreonam-resistant phenotype while hyperproduction of both TEM-1 and SHV-1 increased the resistance to amoxycillin/clavulanic acid and to cephalothin.

Ceftazidime↗
PubMed1992

Structural rearrangements of chromosome 13 as additional abnormalities in Burkitt lymphoma and type 3 acute lymphoblastic leukemia.

We report three cases of chromosome 13 rearrangements as additional abnormalities in two patients with Burkitt lymphoma (BL) and one with type 3 acute lymphoblastic leukemia (ALL). Involvement of chromosome 13 has been reported most often as 13q+, without identification of the supplementary chromosomal material; in our three cases with 13q+, we identified two duplications: dup(13)(q13q22) and dup(13)(q21q22).

Aged↗
PubMed1992

Characterization of chromosomally encoded penicillinases in clinical isolates of Klebsiella pneumoniae.

Four Klebsiella pneumoniae strains, isolated in two geographically distant French hospitals, were found to produce constitutive beta-lactamases with an unusual isoelectric point for this species (8.1). The four enzymes were chromosomally encoded and related to the Ambler's class A plasmid-mediated SHV-type enzymes. The four enzymes were predominantly penicillinases, with good activity against amino- and ureidopenicillins. They poorly hydrolysed cephalothin, cephaloridine and cefoperazone and did not hydrolyse third-generation cephalosporins and aztreonam. The four enzymes were susceptible to the inhibitory effect of clavulanic acid. Finally, the strains were all found to produce an acetyl-esterase. The acetyl-esterases catalysized hydrolysis of the acetoxy group of cephalothin and cefotaxime although this did not affect their antibacterial activities. These esterases were not susceptible to the inhibitory effect of clavulanic acid and EDTA.

Chromosomes, Bacterial↗
PubMed1992

Evidence for a correlation between auxin production and host plant species among strains of Pseudomonas syringae subsp. savastanoi.

Auxin production by 131 strains of Pseudomonas syringae subsp. savastanoi was investigated with the aim of looking for correlations among this characteristic and the origin of the strains, the types of symptoms, and the host plant. Most of the P.syringae subsp. savastanoi strains, except those isolated from ash, produced auxin and harbored iaa genes. Among ash strains, which were pathogenic only on ash, only 2 out of 33 were found to produce auxin and to harbor iaa genes.

Indoleacetic Acids↗
PubMed1992

Correlation between echographic gastric emptying and appetite: influence of psyllium.

The correlation between ultrasonographic gastric emptying and appetite was studied. Echographic evaluation of gastric emptying by measurement of the antral vertical diameter and assessment of sensations of hunger and satiety using analogue visual scales were performed simultaneously in 12 healthy volunteers. Measurements were carried out after the intake of 10.8 g psyllium or placebo in a randomised, crossover, double blind trial. The correlation between echographic gastric emptying and sensations of hunger and satiety was excellent (p < 0.001) after the intake of either psyllium or placebo. Psyllium significantly delayed gastric emptying from the third hour after a meal. It increased the sensation of satiety and decreased hunger at the sixth hour after the meal. The association between echographic measurement and visual scales is a simple method of evaluating the relationship between the stomach and appetite. The pharmacodynamic effect of psyllium should be confirmed by longterm therapeutic trials.

Adolescent↗
PubMed1992

Anti-lamin-B autoantibodies in a patient with cold urticaria.

Anti-lamin-B autoantibodies at a significant level had been found on two occasions in the serum of a 56-year-old woman who was suffering from an apparently idiopathic chronic cold urticaria. Anti-lamin autoantibodies can be detected in various autoimmune disorders including hepatitis, vasculitis and peripheral blood cytopenia. In our patient, there was no other clinical or biological abnormality. A chance association cannot be ruled out.

Autoantibodies↗
PubMed1992

[Leg cellulitis caused by Aeromonas hydrophila. Medical treatment].

A case of cellulitis of the leg caused by Aeromonas hydrophila in a cirrhotic patient is reported. The starting point of the infection could not be determined with certainty, but a direct local inoculation during foot-baths was suspected. Because of clinical signs suggestive of erysipelas, the disease was initially treated without success with penicillin G, which raises questions concerning the choice of the initial antibiotic therapy for cellulitis of the leg in immunocompromised patients, pending the bacteriological results. A purely medical treatment (adequate antibiotic therapy) resulted in complete cure of this patient, despite the fact that his lesions were necrotizing.

Aeromonas hydrophila↗
PubMed1992

[Isolated hemangioma of the left ventricle. Value of coronaroangiography for the etiological diagnosis].

A four year old child was admitted for investigation of a cardiac murmur and cardiomegaly. Echocardiography showed a large left ventricular tumour, the extension of which was accurately defined by nuclear magnetic resonance imaging and the etiology confirmed by coronary angiography. Holter recordings showed salvoes of ventricular tachycardia. This is an interesting case because, despite echocardiography and nuclear magnetic resonance imaging, the precise nature of the tumour was revealed only by coronary angiography. This investigation also showed a significant decrease of the left ventricular ejection fraction. It is the only described haemangioma complicated by this type of ventricular hyperexcitability. Therefore, coronary angiography would seem to be necessary in the investigation of isolated myocardial masses which remain unidentified by non-invasive methods.

Cardiomegaly↗
PubMed1992

[Photodynamic therapy by coloring laser. Can it represent a therapeutic alternative for small epidermoid cancers of the esophagus?].

Our aim was to assess the efficacy of photodynamic therapy in inoperable patients with small esophageal carcinoma. Eleven patients were treated for squamous cell carcinomas ranging in size from 1 to 3 cm2. Hematoporphyrin (between 3 and 5 mg/kg) was injected intravenously and then the tumor irradiated at endoscopy 72 hours later with a dye laser (630 nm) at an energy of 250 joules/cm2. Complete destruction of the lesion was obtained in 6 cases with negative biopsies at 1 month. In all 6 patients, no recurrence was seen after a median follow-up of 4 months (range: 2-38). Partial destruction of the tumor was obtained in 4 cases while treatment was a complete failure in the last patient. Two instances of mild cutaneous photosensitization occurred. Two patients treated for recurrence after radiotherapy, died of esophageal perforation directly related to the procedure. Photodynamic therapy appears to be a possible effective treatment for esophageal squamous cell carcinoma in inoperable patients when other curative treatment modalities are not possible.

Aged↗
PubMed1992

[Results of the surgical repair of branch pulmonary artery stenosis in tetralogy of Fallot].

This study was based on the follow-up of 55 patients with tetralogy of Fallot and operated for branch pulmonary artery stenosis. Twenty two patients were followed up clinically (Group I): 91% of the patients were asymptomatic at the end of the first operative year. Thirty three patients (Group II) underwent control catheter studies after an average of 2.5 years after complete repair: only 70% of these were asymptomatic at 1 year; 8 were reoperated after an average of 3.6 years. The surgical result could only be evaluated by control catheter studies. The results were therefore based on the data obtained from Group II: this selection resulted in a pessimistic bias as the outcome in the two groups was significantly different. The stenoses were congenital and/or iatrogenic. They were located on the left branch (55%), the right branch (9%), the bifurcation (24%), separately on the two branches (12%). The diversity of the operative techniques and materials used reflects the difficulty of this surgery. The cumulative results were good in 33% of cases, average in 28% and poor in 39%. The results were better in isolated branch stenosis than in stenosis of the bifurcation, though not statistically significant. The results were related to age, body weight, the type, the site, the length, the association of stenoses and the material used. Significant predictive factors for a good result were: Gore-Tex (p less than 0.05) and pericardial pedicle (p less than 0.005). The average follow-up of patients with the latter type of patch was only 2 years. These results require confirmation by studies of larger numbers of patients followed up for a longer period.

Cardiac Catheterization↗