Arylneuraminidase activity of Pseudomonas aeruginosa does not degrade natural substrates such as human respiratory mucins.

The culture supernatant from a single Pseudomonas aeruginosa strain has been reported to show neuraminidase activity, leading to the speculation that this bacterium may use this enzyme as a virulence factor to act on host macromolecules. In order to extend this finding, we have examined the activity of concentrated P. aeruginosa culture supernatants and cells on synthetic and natural substrates containing sialic acid, such as human respiratory mucins. Four P. aeruginosa strains showed some activity on the synthetic substrate 4-methylumbelliferyl-alpha-D-N-acetylneuraminic acid but failed to liberate N-acetylneuraminic acid from six different natural substrates. Attempts to induce enzyme production by use of human respiratory mucins in the culture medium were also unsuccessful. The supernatants also showed N-acetyl-beta-D-glucosaminidase-like activity on a synthetic substrate but did not liberate N-acetylhexosamines from natural substrates. We conclude that the neuraminidase-like activity observed in P. aeruginosa can be defined as an arylneuraminidase and that the possession of a neuraminidase active on natural substrates is not a common attribute of P. aeruginosa strains.     

Cell and cytokine profiles in nasal secretions from patients with nasal polyposis: effects of topical steroids and surgical treatment

BACKGROUND: Nasal polyposis (NP), a chronic inflammatory disease of the paranasal sinus mucosa, is frequently associated with asthma. Previous reports showed that surgical treatment for nasal polyps may influence asthma evolution. We hypothesized that sinus surgery may alter the cytokine network in nasal secretions. METHODS: We evaluated the characteristics (cells and mediators) of nasal lavages in nine patients with untreated NP (group A), 17 patients treated with topical steroids (group B), 21 patients treated by nasal surgery endonasal ethmoidectomy associated with topical steroids (group C), and 12 healthy subjects (controls). RESULTS: Percentages of both eosinophils and neutrophils were higher in NP patients than in controls. Percentages of eosinophils and interleukin-5 (IL-5) level were higher in group A than in group C and controls. There was a positive correlation between IL-5 and eosinophils. In marked contrast, IL-8, IL-10, and IL-1beta levels were significantly higher in group C than in groups A and B and controls; TNF-alpha concentration was significantly lower in group C than in groups A and B and controls; and there was a negative correlation between IL-10 and TNF-alpha. The percentage of eosinophils was higher in asthmatic patients with NP than in nonasthmatic patients. In addition, in group C, asthmatic patients also had a significantly higher level of IL-10 than nonasthmatic patients. CONCLUSIONS: Our study demonstrates that percentages of eosinophils and neutrophils, and IL-5 level were increased in nasal secretions from untreated patients with NP. Topical steroid treatment is associated with a decrease of inflammatory cells and mediators. In marked contrast, nasal surgery is associated with marked changes, in cytokine profile in nasal secretions, that are clearly different from those of controls and topical steroid-treated NP patients.     

Pseudomonas aeruginosa recognizes carbohydrate chains containing type 1 (Gal beta 1-3GlcNAc) or type 2 (Gal beta 1-4GlcNAc) disaccharide units.

The adhesion of Pseudomonas aeruginosa to type 1 (Gal beta 1-3GlcNAc) and type 2 (Gal beta 1-4GlcNAc) disaccharide determinants was studied in a microtiter adhesion assay and a thin-layer chromatography bacterial overlay assay. The oligosaccharides were prepared from human breast milk and human urine and were conjugated to hexadecylaniline to form neoglycolipids that were used in were used in the assays. Both the mucoid and the nonmucoid strains that were studied recognized the disaccharide determinants Sialylation of the oligosaccharides did not suppress binding in the thin-layer chromatography assay, but alpha 2-6-linked sialic acid blocked binding in the microtiter assay. The use of bovine serum albumin instead of gelatin as a blocking agent against nonspecific binding completely suppressed binding in the thin-layer chromatography assay. Isogenic nonpiliated mutants of nonmucoid strains constructed by interrupting the pilin gene retained their adhesive capacity for the disaccharide units, indicating that binding to the disaccharides was mediated by a nonpilus adhesin(s). Furthermore, two monoclonal antibodies that recognize the type 2 disaccharide determinant (Gal beta 1-4GlcNAc) partially inhibited adhesion of a pair of piliated and nonpiliated isogenic strains to mucin. This study suggests that P. aeruginosa utilizes a nonpilus adhesin(s) to bind to disaccharide units commonly found in mucins, in addition to pili and alginate, two previously described adhesins.     

Vaginal vault suspension by posterior transobturator sling

OBJECTIVE: A study on the feasibility and safety of a new surgical procedure of vaginal vault suspension using a polypropylene mesh placed in the uterovaginal septum by a posterior transobturator approach. PATIENTS AND METHODS: Longitudinal study from March 2002 to January 2006 of patients treated by this new surgical procedure. Postoperative visits, including an interview and a physical examination were made at two, six and 12 months and annually thereafter. The minimal required follow-up time was 12 months up to January 2007. RESULTS: Seventy-eight patients were included. Three cases of intraoperative bleeding occurred. In these cases no transfusion was required and no complications were observed later on. The mean hospital stay was five days (range 3-9). The mean follow-up time was 20.36 months (range 12-48). Six recurrences were observed in the medial compartment (8%) and two anterior recurrences (2%). There was no recurrence in the posterior compartment. New-onset moderate dyspareunia was noted in 13% of the cases and a severe in two cases. No erosion occurred. DISCUSSION AND CONCLUSION: The analysis of our experience shows that vaginal vault suspension by posterior transobturator approach is a safe and simple procedure, and demonstrates its median efficacy. Further, this study should confirm these results over the long-term follow-up.     

Cancer : saison 1 et saison 2

A 42 years patient with breast cancer relates the announcement of her disease, four years ago, associated with a denial of the disease. The recurrence of the disease under the form of bone metastasis, a year ago, erases the initial selfdenial strategy. The patient’s life and rythm are therefore shattered; the patient’s paintings reveal this evolution. The psychotherapy engaged at the beginning of the disease allows a return to a repressed past and the search of the “father’s name”.     

Neonatal status epilepticus due to lamination disorder without significant cell death

Background: Malformations of the cerebral cortex may be associated with severe epilepsy and status epilepticus. It has been shown that status epilepticus models induce excitotoxic cell death. In humans, very few data are available. Case and results: We report a case of a multifocal disorder of the lamination diagnosed in a neonate, borne at 30 weeks’ gestation, who died from a refractory status epilepticus at two months and half. This abnormality was not detected by repeated MRI studies. Only microscopic investigations permitted to identify this disorder of the lamination. We found also little cell death or cell loss. Discussion: Our report highlights the possible false negative results of MRI in a newborn. We can also discuss that immature human brain maybe less sensitive to neuronal injury than mature as described in animal models.