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D Bonnet

Publications and source records attributed to D Bonnet.

At least 217 records · Page 12Linked to original sources
PubMed1995

[Goodpasture syndrome: role of an epidemiological factor? Apropos of two cases].

Goodpasture's syndrome is a rare pneumorenal syndrome. Although the antigenic target of this auto-immune disorder is now known, its etiology remains debated. We report two cases of Goodpasture's syndrome occurring in similar epidemiologic conditions concerning the moment the disease began, the age and sex of the patients, their place of residence and work and manipulation of chemicals. Thus, a common environmental factor could have been the trigger event of the Goodpasture's syndrome. The epidemiologic features of this disease are reviewed.

Adult↗
PubMed1995

[Percutaneous occlusion of patent ductus arteriosus by the Rashkind double-umbrella device].

BACKGROUND: The transcatheter option consisting of implanting and releasing an occlusive device designed as a double-umbrella is an interesting alternative to surgery aimed to close persistently patent ductus arteriosus. POPULATION AND METHODS: Closure of a duct with the Rashkind device had been planned in 113 children. The procedure was abandoned in 12 with inadequately sized ducts (too large or too small). This study therefore included 101 attempts in patients aged 2.3 months to 18.5 years (m +/- 1 SD = 45.9 +/- 43.2 months) whose weights ranged from 3.3 to 87 kg (m +/- 1 SD = 15.7 +/- 11.7 kg). The narrowest dimension of the duct on the aortograms ranged from 1.2 to 6.2 mm (m +/- 1 SD = 2.9 +/- 0.9 mm). RESULTS: The procedure failed in seven patients because of a too large and/or tubular vessel, causing removal of the device prior to release in five patients, or surgical extraction after it had embolized into a pulmonary artery branch in two patients. An early acute hemolysis requiring again the surgical removal of an instable device in a tubular duct was seen in one case. Two patients had femoral artery occlusion successfully treated with thrombolytic agents. Complete occlusion was immediately proven in 32 (35%) of the 92 successful and stable implantations. These figures raised to 64% (59 cases) prior to discharge. At final follow-up (0.3-59 months, m +/- 1 SD = 13.8 +/- 14.4 months), another 16 total occlusions were observed and one patient was successfully managed by a second implantation. The final occlusion rate was 83% (76 cases). Of the 16 residual shunts, five were surgically suppressed and the remaining were minimal. CONCLUSION: Transcatheter occlusion of the patent ductus arteriosus is safe in children weighing more than 5 kg, having ducts with a narrowing ranging from 1 to 6 mm. It is efficient in five out of six cases and has less disadvantages than surgery.

Adolescent↗
PubMed1995

Transient induction of a peroxidase gene in Medicago truncatula precedes infection by Rhizobium meliloti.

Although key determinative events of the Rhizobium-legume symbiosis are likely to precede bacterial infection, no plant genes have been identified that are expressed strongly prior to infection and nodule morphogenesis. A subtractive hybridization-polymerase chain reaction technique was used to enrich for genes induced during the early phases of the R. meliloti-Medicago truncatula symbiosis. One gene so identified encodes a putative plant peroxidase protein, which we have named Rip1 for Rhizobium-induced peroxidase. The accumulation of rip1 transcript was rapidly and transiently induced by R. meliloti and by the corresponding lipooligosaccharide signal molecule Nod factor RmIV, which was both necessary and sufficient for rip1 induction. The duration of maximal rip1 expression coincided with the preinfection period: transcript levels for rip1 were near maximal by 3 hr postinoculation and declined by 48 hr, coincident with early infection events and the onset of nodule morphogenesis. Furthermore, although rip1 induction preceded bacterial infection by at least 24 hr, the transcript was localized to epidermal cells in the differentiating root zone that was subsequently infected by Rhizobium. Thus, a defining feature of the Rhizobium infection court is the prior induction of rip1 expression.

Amino Acid Sequence↗
PubMed1995

Comparison of the inhibitory effect of AcSDKP, TNF-alpha, TGF-beta, and MIP-1 alpha on marrow-purified CD34+ progenitors.

The aim of this study was to compare the inhibitory effect of the tetrapeptide AcSDKP, tumor necrosis factor-alpha (TNF-alpha), which contains the sequence of the peptide, transforming growth factor-beta (TGF-beta), and macrophage inflammatory protein-1 alpha (MIP-1 alpha) on sorted CD34+ cells using both proliferation and clonogenic assays. Although a short treatment with any of the molecules decreased the growth of colony-forming unit granulocyte/macrophage (CFU-GM) and burst-forming unit-erythroid (BFU-E) progenitors (except for TNF-alpha as it is a greater inhibitor for CFU-GM), further experiments using a 6-day liquid culture in the presence of a combination of growth factors (recombinant human interleukin-3 [rhIL-3], IL-6, IL-1 beta, GM colony-stimulating factor [GM-CSF], G-CSF, erythropoeitin [Epo], and stem cell factor [SCF]) allowed us to determine a number of differences between their effects: 1) TGF-beta and TNF-alpha induced a stronger decrease in the proliferation and clonogenicity of CD34+ subsets than MIP-1 alpha and AcSDKP, 2) the dose-response curves appeared different, and 3) contrary to TGF-beta and TNF-alpha, AcSDKP and MIP-1 alpha required repeated addition to induce inhibition. Therefore, our data clearly show that while the inhibitory effect of TNF-alpha and AcSDKP appeared to be different, there is a close similarity in the effect of AcSDKP and MIP-1 alpha on normal human progenitor response to the combination of growth factors used.

Antigens, CD↗
PubMed1995

[Personality disorders in childhood. Classifications and clinical aspects of border-line personalities and narcissism].

The diagnosis of personality disorders is particularly difficult in childhood and requires prolonged psychiatric evaluation. Authors focus discussion upon the diagnosis of borderline and narcissistic personality disorders in children. Although Misès recently favours the term child borderline pathologies covering all personality disorders other than psychosis or neurosis, the american school of psychiatry tends to separate different personality disorders according to DSM-IV diagnosis propositions. The results of rare prospective studies suggest a pathological continuum which remains within the sphere of personality disorders. Further research is in fact necessary to determine the specific evolutive profiles of each personality disorder.

Borderline Personality Disorder↗
PubMed1995

[Round pulmonary lesions after returning from French Guyana. Six cases of american pulmonary histoplasmosis].

From 1989 to 1994, 71 patients were hospitalized for diagnosis of round lung lesions including 49 servicemen under the age of 45 years who had been stationed in tropical areas. In 6 of these servicemen, the diagnosis was pulmonary histoplasmosis at the tertiary stage of histoplasmoma. All had done duty in French Guyana and were negative for human immunodeficiency virus. The subpleural lung opacity was the only lesion in 5 out of 6 patients and was calcified in 4 out of 6 patients. Since skin tests with histoplasmin and serologic testing for histoplasmosis failed to achieve definitive diagnosis, surgical biopsy was performed by conventional thoracotomy in 2 cases and video-assisted thoracic surgery in 4 cases. The specimens obtained confirmed diagnosis of histoplasmosis on mycologic criteria in 3 cases and on a combination of findings including compatible histologic evidence in 3 cases. Treatment consisted in surgical excision of the nodules, for which video-assisted thoracoscopic surgery proved to be an excellent technique because of its simplicity and rapidity.

Adult↗
PubMed1995

[Gene localisation in 12q12 in Holt-Oram atrio-digital syndrome].

The Holt-Oram syndrome, first described in 1960, consists of non-cyanotic congenital heart disease, usually an atrial septal defect, arrhythmias and malformations of the upper limbs affecting the radial segment. The transmission of the syndrome is autosomal dominant with almost complete penetrance. The authors report the localisation of a genetic abnormality of the Holt-Oram syndrome on the long arm of chromosome 12 (12q21-q3) by analysis of linkage in 9 multiplex families (Zmax = 8.19 at locus D12S354). Multipoint analysis showed a genetic interval of 7 centimorgans containing a gene of the Holt-Oram syndrome between loci D12S84 and D12S79 (multipoint lod score, 10 g base 10 = 8.96). In situ hybridization of artificial yeast chromosomes containing the surrounding markers showed that a gene of the Holt-Oram syndrome is located in 12q23-q24. The genetic heterogeneity was demonstrated in 3 families of the Holt-Oram syndrome with polydactyly or without cardiac disease (homog-test: chi 2 = 13.28; p = 0.0001). The localisation of a gene of the Holt-Oram syndrome is, to the authors' knowledge, the first chromosomal localisation of a cardiac malformation with septal defects in man. The identification of this gene should open wide perspectives for genetic research of cardiac morphogenesis and clarify the molecular mechanisms which govern cardiac septation during embryogenesis.

Chromosome Mapping↗
PubMed1995

[Pulmonary atresia with ventricular septal defect: therapeutic strategy in newborn infants].

Pulmonary atresias with ventricular septal defect, a right ventricular infundibulum and pulmonary artery separated by an imperforated membrane and a complete pulmonary tree with two branches in continuity are called "favourable" forms of this malformation. The authors studied 29 neonates, less than 1 month old, in whom the malformation was both ductus- and prostaglandin-dependent, prostaglandin infusion being essential for pulmonary flow and impossible to stop because of the resulting severe hypoxia. The choice of treatment depended on the anatomical form defined by angiocardiography. In the 19 regular forms with regular pulmonary arteries with little hypoplasia, percutaneous perforation-dilatation was successful in 3 out of 5 attempts with one secondary death and 2 good results leading to complete repair; anastomosis was performed in 9 cases with 3 deaths, 1 partial result and 5 good results which were followed by complete repair in 3 cases; primary complete repair attempted in 7 cases led to 1 death and 6 successes completed in 3 cases by reoperation for left pulmonary artery stenosis. In the 10 less favourable anatomical forms with stenosis or severe hypoplasia or the pulmonary branches, only palliative procedures were proposed: 2 perforations-dilatations which only gave partial results, 7 anastomoses with 1 death and 4 partial results; and 1 ventriculo-pulmonary connection without closure of the ventricular septal defect (good result). In view of the good results obtained over the 6 years of the study, the authors advise primary complete correction for the anatomically favourable forms of the malformation when weaning from prostaglandin infusion is impossible.(ABSTRACT TRUNCATED AT 250 WORDS)

Angiocardiography↗
PubMed1995

[Percutaneous dilatation of recurrent coarctation of the aorta in the 1st year of life].

It is not rare for surgery of coarctation of the aorta to be complicated by recurrence of the lesion at medium-term, especially when it is performed very early in life. Advances in interventional catheterisation now offer an alternative to surgical reoperation. This study is a retrospective analysis of balloon angioplasty in 20 patients in whom isthmic stenosis had been operated before the age of one month in 19 cases, in whom recurrent coarctation was identified 3.2 +/- 2.1 months later. The percutaneous angioplasty was performed by a femoral arterial approach at an average age of 5.4 +/- 2.3 months. The femoral pulses returned together with a fall in the transisthmic systolic pressure gradient from 58.3 +/- 23.4 mmHg to 18.3 +/- 12.5 mmHg, and the isthmic lumen increased by +117 +/- 52%. Judged by the residual pressure gradient, the results were good, the best results being observed in the shortest and most severe stenoses. After a maximum follow-up of 5 years (average: 20.1 +/- 16.6 months), the angioplasty was successful in 14 cases (70%), 4 cases had a mild residual gradient (20%) and 2 were failures (10%). None of the patients required reoperation. There were no fatalities or early aneurysmal complications in the dilated zone monitored by echocardiography and magnetic resonance imaging. The only complication was femoral artery obstruction (6 cases) which was successfully thrombolysed in 5 cases but which recurred at long-term in 3 cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic Coarctation↗
PubMed1995

Inhibitory peptides in hematopoiesis.

This paper will review the present knowledge on two small chemically unrelated peptides, the pentapeptide pGlu-Glu-Asp-Cys-Lys (pEEDCK) and the tetrapeptide acetyl-N-Ser-Asp-Lys-Pro (AcSDKP, Seraspenide) focusing on 1) their inhibitory effects on normal hematopoiesis, 2) their effect on malignant cells, especially leukemic cells, and 3) their potential clinical use as marrow protectors during cancer therapy.

Animals↗
PubMed1994

Site-directed mutagenesis of the P2 region of the Rous sarcoma virus gag gene: effects on Gag polyprotein processing.

The Pr76Gag and Pr180Gag-Pol polyprotein precursors of Rous sarcoma virus contain a 22-amino-acid spacer peptide, called p2, located between the amino acid sequences of the mature Gag proteins MA and p10. This spacer peptide is present in stoichiometric amounts in the virion, albeit cleaved into two parts, but its function is unknown. The primary sequence of this peptide includes a region that is highly conserved among retroviruses, consisting of four prolines followed by tyrosine. We have investigated the role of p2, particularly the polyproline motif, in the virus life cycle by site-directed mutagenesis. Mutations in this region result in the intracellular accumulation of a truncated Gag precursor, due either to a block in the intracellular processing of the precursor or to the premature activation of the viral protease. Since in cells infected by Rous Sarcoma Virus there is no significant intracellular processing of the Gag polyprotein precursor, our data suggest that the p2 domain plays a role in controlling the activation of the protease. These mutations also result in a reduction in virus particle release, probably as a direct consequence of the aberrant precursor processing since a construct in with both p2 and the protease active site were mutated did not exhibit aberrant processing of the Gag polyproteins and formed particles with an efficiency similar to that of the wild type. This indicates that it is the viral protease that is responsible for the aberrant processing and suggests that the p2 region is not required for assembly. Although the virus genomic RNA packaged into virions produced by the p2 mutants is more susceptible to degradation, it appears that the p2 domain does not have a direct role in RNA packaging and protection.

Amino Acid Sequence↗
PubMed1994

A gene for Holt-Oram syndrome maps to the distal long arm of chromosome 12.

Holt-Oram syndrome (HOS) is an autosomal dominant condition of unknown origin characterized by congenital septal heart defects with associated malformations of the upper limbs (radial ray). Here, we report on the mapping of a gene causing HOS to the distal long arm of chromosome 12 (12q21-qter) by linkage analysis in nine informative families (Zmax = 6.81 at theta = 0 at the D12S354 locus). Also, multipoint linkage analysis places the HOS gene within the genetic interval between D12S84 and D12S79 (multipoint lod-score in log base 10 = 8.10). The mapping of a gene for HOS is, to our knowledge, the first chromosomal localization of a gene responsible for congenital septal heart defect in human. The characterization of the HOS gene will hopefully shed light on the molecular mechanisms that govern heart septation in the early stages of embryogenesis.

Abnormalities, Multiple↗
PubMed1994

[Demonstration of subclinical pulmonary alveolitis in spondylarthropathies].

Restrictive ventilatory dysfunction, lowered diffusing capacity, and apical fibrosis have been reported in ankylosing spondylitis. To investigate the pathogenesis of these abnormalities, we studied distal airspace cytology by performing bronchoalveolar lavage in 34 spondyloarthropathy patients (ankylosing spondylitis, n = 16; reactive arthritis, n = 4; axial psoriatic arthritis, n = 2; and undifferentiated spondyloarthropathy with HLA B27-positivity in every case but one, n = 12). Mean age was 32.4 +/- 13.7 years. None of the study patients had apical fibrosis, lower respiratory tract infection, or exposure to airborne pollutants other than tobacco smoke. The control group was composed of nine subjects who had no lung or inflammatory diseases and were not using medications. Significantly higher proportions of lymphocytes were found in bronchoalveolar lavage specimens from patients, as compared with controls. This difference was not influenced by smoking or medication use (non steroidal antiinflammatory drugs, sulfasalazopyridine). Alveolar lymphocytosis was not correlated with laboratory tests for disease activity (erythrocyte sedimentation rate, serum IgA levels) or with the presence of restrictive ventilatory dysfunction. Increases in the proportion of lymphocytes were of similar magnitude in patients with ankylosing spondylitis and in those with other spondyloarthropathies. Absolute total cell counts and relative neutrophil counts were similar in patients and controls. However, among the patients with spondyloarthropathies, those with a disease duration of more than five years had a significantly higher proportion of neutrophils than those with a disease duration of less than five years. These findings demonstrate that spondyloarthropathy patients have subclinical lymphocyte alveolitis. Although of unclear significance, this alveolitis may be related to the development of apical fibrosis in some patients with ankylosing spondylitis.

Adult↗