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L de Saint Martin

Publications and source records attributed to L de Saint Martin.

7 recordsLinked to original sources
PubMed2004

Chlamydia pneumoniae IgG serological status and venous thromboembolism: a cross-sectional hospital based study.

OBJECTIVE: To search for a link between Chlamydia pneumoniae serological status and venous thromboembolic disease. METHODS: From March 1992 to October 1999, we conducted a cross-sectional hospital-based study of consecutive unselected outpatients referred to us for clinical suspicion of venous thromboembolism. We compared the Chlamydia pneumoniae serological status with respectively, the venous thromboembolism, the deep vein thrombosis and the proximal deep vein thrombosis status. RESULTS: Among 1193 patients registered for suspected venous thromboembolism, 1010 samples were available (499 negative and 511 positive patients for venous thromboembolism). Seventy-nine patients were Chlamydia pneumoniae positive. Our work failed to demonstrate any clear association between Chlamydia pneumoniae and venous thromboembolism status. Nevertheless, we identified a statistical difference regarding Chlamydia pneumoniae seropositivity and proximal vein thrombosis status (adjusted odds ratio of 1.70, CI95%: 1.05 to 2.77). CONCLUSION: The presence of Chlamydia pneumoniae antibodies might be a minor risk factor for venous thrombosis.

Aged↗
PubMed2001

A cross sectional study of antiphospholipid-protein antibodies in patients with venous thromboembolism.

OBJECTIVE: To look for an association between venous thromboembolism (VTE) and antiphospholipid antibodies (aPL) in patients without Systemic Lupus Erythematosus (SLE) when implementing, beside conventional assays, new tests for aPL screening directed towards purified proteic targets. METHODS: We conducted a cross-sectional, hospital-based study of consecutive unselected outpatients. We compared VTE+ patients to VTE- among 398 consecutive unselected outpatients referred for clinical suspicion of VTE. To detect aPL, the following ELISAs were performed: 1) a conventional standardized ELISA 2) an improved APA assay, 3) an anti-Beta2GPI ELISA, 4) an anti-Annexin V ELISA, 5) an anti-Prothrombin ELISA. We sought an association between VTE and aPL through a quantitative (t-test) and a qualitative comparison (chi-square test, according to the cut-off values set as the 95th percentile of aPL distribution). First we conducted an analysis of all patients. Then we stratified them into 2 subgroups, with or without a wellknown risk factor for VTE (prolonged immobilization >72h, surgery or trauma within the past three months, current malignancy). RESULTS: 61% of patients were classified as VTE-positive. Before stratification, we did not find any significant association between the VTE status and aPL. However, after stratification, in the subgroup without risk factors for VTE, the frequency of positive values as regards the anti Prothrombin antibodies detection was significantly higher in VTE+ patients (p = 0,04). CONCLUSION: The presence of anti Prothrombin antibodies might be an independent risk factor of VTE. However systematic screening for aPL in non SLE patients referred for VTE suspicion at the time of the thrombo-embolic event has little clinical relevance.

Adult↗
PubMed1997

Interaction of Neisseria meningitidis with a polarized monolayer of epithelial cells.

An important step in the pathogenesis of Neisseria meningitidis is the crossing of two cellular barriers, one in the nasopharynx and one in the brain. To approach the mechanisms by which this bacterium can achieve these goals, we studied the interactions between N. meningitidis and a monolayer of polarized tight junction-forming T84 cells grown on filter units. A capsulated, piliated, Opa-, and Opc- N. meningitidis strain is shown to be capable of adhering to and crossing this monolayer several orders of magnitude more efficiently than an isogenic nonpiliated derivative. This bacterial interaction does not affect the barrier function of tight junctions, as assessed by (i) the absence of modification of the transepithelial resistance, (ii) the lack of increase of [3H]inulin penetration across the monolayer, and (iii) the absence of delocalization of ZO-1, a tight junction protein. Electron microscopy studies and confocal examinations demonstrated that N. meningitidis (i) induces cytoskeletal rearrangements with actin polymerization beneath adherent bacteria, (ii) is intimately attached to the apical membrane of the cells, and (iii) can be internalized inside cells. Immunofluorescent staining with antipilus antibodies showed evidence that meningococcal piliation was dramatically reduced at later time points of bacterial cell interaction compared to the early phase of this interaction. In addition, adhesive bacteria recovered from an infected monolayer are piliated, capsulated, Opa-, and Opc-, a phenotype similar to that of the parental strain. Taken together, these data demonstrate that following pilus-mediated adhesion, N. meningitidis is involved in an intimate attachment which requires a bacterial component different from Opa and Opc and that meningococci cross a monolayer of tight-junction-forming epithelial cells by using a transcellular pathway rather than a paracellular route.

Actins↗
PubMed1995

The Neisseria meningitidis haemoglobin receptor: its role in iron utilization and virulence.

The Neisseria meningitidis haemoglobin receptor gene, hmbR, was cloned by complementation in a porphyrin-requiring Escherichia coli mutant. hmbR encodes an 89.5 kDa outer membrane protein which shares amino acid homology with the TonB-dependent receptors of Gram-negative bacteria. HmbR had the highest similarity to Neisseria transferrin and lactoferrin receptors. The utilization of haemoglobin as an iron source required internalization of the haemin moiety by the cell. The mechanism of haemin internalization via the haemoglobin receptor was TonB-dependent in E. coli. A N. meningitidis hmbR mutant was unable to use haemoglobin but could still use haemin as a sole iron source. The existence of a second N. meningitidis receptor gene, specific for haemin, was shown by the isolation of cosmids which did not hybridize with the hmbR probe, but which were able to complement an E. coli hemA aroB mutant on haemin-supplemented plates. The N. meningitidis hmbR mutant was attenuated in an infant rat model for meningococcal infection, indicating that haemoglobin utilization is important for N. meningitidis virulence.

Aldehyde Oxidoreductases↗
PubMed1995

Balint's syndrome.

Explore the source record for details and available documents.

Acquired Immunodeficiency Syndrome↗
PubMed1993

[Generalized BCG infection after intravesical instillations of Calmette-Guerin bacillus].

BCG has been disappointing as immunotherapy of numerous cancers, but it has been clinically successful in the intravesical treatment of bladder carcinomas sparing the muscle coat; it has indeed become the reference treatment for this type of cancer. However, complications are repeatedly reported, including generalized BCGitis. We report such a case with positive BCG culture. From the cases already published there emerges a homogeneous and often subacute clinical presentation suggestive of an ordinary pathogen. Bacteriology is not very helpful, even when recent techniques are used, and therefore the diagnosis rests on the context and, when samples are taken, on suggestive histological findings. To discuss the physiopathology of BCGitis--generalized immune reaction or multifocal BCG proliferation--is not useless since treatment depends on it. It is probable that these 2 mechanisms working together can be incriminated justifying the prescription of both antibiotics and corticosteroids. When this is done, the prognosis seems to be favourable in most patients. Yet a strict respect of contra-indications and a very careful subsequent radiotherapy should reduce the risks.

Administration, Intravesical↗