Géodynamique andine : résumé étendus = Andean geodynamics : extended abstracts

Les données isotopiques Sr, Nd et Pb des roches volcaniques miocènes à récentes de la région du Salar d'Antofalla et de la Cordillère andine adjacente (sud Puna, NW argentin) montrent une zonation entre deux régions. Ceci est attribué à des variations de composition du socle précambrien sous-jacent, et n'est pas dû à différents types de socles sous des terrains allochtones possiblement accrétés entre ces deux régions. (Résumé d'auteur

OmpA and antigenic diversity of bovine Chlamydophila pecorum strains

Infections with the intracellular bacterium Chlamydophila (C.) pecorum are highly prevalent worldwide in cattle. These infections cause significant diseases such as polyarthritis, pneumonia, enteritis, genital infections and fertility disorders, and occasionally sporadic bovine encephalomyelitis. Subclinical respiratory infections of calves with C. pecorum have been associated with airway obstruction, pulmonary inflammation, and reduced weight gains. This investigation examined four chlamydial strains with biological properties of C. pecorum isolated from feces of clinically normal cattle, from calves with pneumonia, and from bulls with posthitis. The objective was to characterize the evolutionary relationships of these bovine chlamydial isolates to other chlamydiae by genetic analysis of the ompA gene, and by the immunological cross-reactivities in Western immunoblot analysis. PCR typing of the ompA gene identified these isolates as C. pecorum. The OmpA-deduced amino acid dissimilarities between these four strains spanned 10-20%. In phylogenetic analysis, the four isolates clustered with C. pecorum ruminant, porcine, and koala strains of different geographic origins rather than with each other. All four isolates showed different patterns of Western immunoblot reactivity with antiserum against bovine C. pecorum strain LW63, and, interestingly, no cross-reactivity of the OmpA proteins with the anti-LW613 OmpA antibodies. These data underscore the polyphyletic population structure of C. pecorum and suggest that the spectrum of C. pecorum OmpA proteins in a host species can occupy the entire evolutionary bandwidth within C. pecorum. The variant immunoblot reactivities support the notion of considerable genomic plasticity of C. pecorum

Fungal contamination of paraffin wax blocks in a pathology archive

While searching for paraffin wax blocks for research purposes in our archive we detected numerous larval and some dead adult moths. Some wax blocks were riddled with a white-brown crumbling substance. The entire archive was checked and profoundly-infested blocks were separated from unaffected blocks. Mycological and parasitological investigations were performed. Fungi were identified by culture and polymerase chain reaction, which revealed high sequence homology to six different fungal species. The moths were determined to be Nemapogon personellus. A total of 8,484 wax blocks had to be removed from the archive and destroyed. Pathologists should be alerted to the importance of checking the humidity of the air where archival material is stored

Abstract REINAS: the Real-Time Environmental Information Network and Analysis System

and Analysis System (REINAS) is a distributed system supporting the conduct of regional environmental science research at the desk top. Continuous real-time data acquired from dispersed sensors is stored in a logically integrated but physically distributed data base. An integrated problemsolving environment is under development which supports visualization and modeling. REINAS is intended to provide insight into historical, current, and predicted oceanographic and meteorological conditions. REINAS permits both collaborative and single-user scientific work in a distributed environment