Genomic choice of codons in 16 microbial species.

We study the codon usage over whole set of ORFs of 16 unicellular microbial species: eight archaebacteria, seven eubacteria, and one eukarya. We first try to define, for each species, the neutral expected codon usage to better approach subsequently the influence of selection. Overlapping triplets counted from the complete DNA genomic sequence and mean amino acid composition of ORFs allow us to build satisfying expected codon usage for each species. Within species deviation from this neutral model is then studied through Correspondence Analysis and characterization with bias index, N(C)' (effective number of codons reported to neutral model). Our results are compared to previously published ones for three species and let appear good agreement in spite of very different methods. We thus propose set of codons probably preferred by selection for nine other species. In the four last species, no clear preference can be evidenced. Finally, we characterize variation of codon usage over functional categories. We propose that the high degree of bias of proteins involved in translation, ribosomal structure and biogenesis has a positive influence on overexpression of the corresponding genes under optimum growth conditions and is a negative regulator of the same genes when amino acids become limited resources.

[An uncommon cause of persistent fever in France]. / Une fièvre au long cours inhabituelle en France.

Miliary tuberculosis is rare and requires rapid diagnosis. Outcome is fatal in 25% of the cases. Since radiography and laboratory tests contribute little to early diagnosis, clinical findings are primordial. Antituberculosis antibiotic therapy is frequently started before microbiological confirmation of the diagnosis.

[Cyclophosphamide-induced interstitial pneumopathy. Course data of bronchoalveolar lavage apropos of a case and review of the literature]. / Pneumopathie interstitielle liée au cyclophosphamide. Données évolutives du lavage broncho-alvéolaire à propos d'un cas et revue de la littérature.

A patient treated with cyclophosphamide for breast cancer developed functional and clinicoradiological signs of sub-acute diffuse interstitial pneumopathy. Bronchoalveolar lavage revealed lymphocyte alveolitis. Differential diagnoses were excluded and the course was favorable after cyclophosphamide withdrawal. The bronchoalveolar lavage results obtained initially and at follow-up and two previous lavages reported in the literature demonstrate the importance of this examination in the diagnosis of drug-induced pneumopathy.

[An unusual tumor of the mediastinum]. / Une tumeur du médiastin inhabituelle.

We report a case of dual parathyroid adenoma associated with an ectopic gland in the right latero-esophageal region of the mediastinum revealed by asymptomatic hypercalcemia. Because of this dual localization and the lack of MBI uptake on the mediastinal scintigram, thoracotomy was used as the first line approach instead of cervicotomy.

[Travel and patients with allergies]. / Le voyage du sujet allergique.

By changing their surroundings and lifestyle, travelers with allergic conditions exposed themselves to new risks. The main perennial allergens are house dust mites which thrive in tropical areas and can be especially sensitizing. The risk of seasonal reactions to grass-pollens varies from region to region. Reactions to some highly sensitizing respiratory allergens can occur in travelers who return to regions where they were previously exposed. Subjects with food allergies should beware of possible reactions to ingredients in exotic dishes. The bites of several insects can cause anaphylactic reactions. Some medications required for tropical travel (e.g. antimalarial drugs) can trigger severe hypersensitivity reactions. Avoidance of allergens is more difficult during travel. Travelers with allergic conditions should carry alert identification cards and medications for routine as well as emergency treatment including self-injectable adrenaline.

[Travel and chronic respiratory insufficiency]. / Le voyage de l'insuffisant respiratoire chronique.

Changes in climate, altitude and lifestyle during travel confronts patients presenting chronic respiratory insufficiency with special problems. A major challenge is related to high altitude during air travel. To limit risks, a preflight examination is necessary to ascertain respiratory status. Patients requiring oxygen therapy must ensure availability both during the flight and at the destination. Patients with asthma or chronic bronchitis must bring along a sufficient supply of usual inhalers. All patients should carry a doctor's letter describing their condition and listing medications. Using these elementary precautions, patients with chronic respiratory insufficiency can safely enjoy sightseeing and outdoor leisure activities.