Analysis of the dependence of respiratory data during spontaneous ventilation at rest

Inspiratory duration (TI), cycle duration (TTOT), and tidal volume (VT) were continuously measured in 11 normal subjects during 400 respiratory cycles. Small breath to breath changes in these variables were separately analyzed. For each of these variables, successive observations are not statistically independent; "large" values tend to be followed by "large" values. A respiratory feedback may be involved in this sequential dependence. In that case, any known system of respiratory control could be associated with it, even those with time constant or delay longer than one cycle duration.     

Sequence of a human immunoglobulin gamma 3 heavy chain constant region gene: comparison with the other human C gamma genes.

We report the first and complete nucleotide sequence of a human gamma 3 heavy chain constant region gene (C gamma 3). This gene displays the same organization than the others C gamma genes and exhibits normal RNA splice and polyadenylation sites. A comparison of its primary sequence with those of C gamma 1, C gamma 2 and C gamma 4 genes confirms the high degree of homology (95%) of the human family in both coding and non-coding regions, and the divergence of the hinge region. The C gamma 3 gene we sequenced codes for a Gm(b) gamma 3 chain (EZZ). Comparison with other known protein sequences reveals that only two specific aminoacids are involved in the Gm(b) and Gm(g) allotypes, which suggests an important part of the spatial configuration in the allotypic specificities.     

Characterization of temperate phages ofBacillus subtilis

Nine known temperature phages ofBacillus subtilis, including four that are newly isolated (ϱ6, ϱ10, ϱ14, and ϱ18), have been compared. Analysis by serology, immunity, host range, and adsorption site similarity place the phages into four groups: Group I, ϕ105, ϱ6, ϱ10, and ϱ14, which are 80–90% related; Group II, SPO2; Group III, ϕ3T and ϱ11, 100% related; and Group IV, SP16. The phage ϱ18 is largely uncharacterized, but is heteroimmune to other groups.     

Experimental infections with Nematodirus spathiger in rabbits.

The feasibility of infecting laboratory rabbits experimentally with the ovine nematode Nematodirus spathiger was examined. Eight-week-old rabbits were dosed either with 5000 or with 17,000 third-stage larvae and killed on days 10, 21 or 42 post-infection. With the lower dose, 20 to 40% of the inoculum were recovered at necropsy. Similar values were observed with the 17,000 dose on days 10 and 21 post-infection, but on day 42 the worm population was residual (0.6%). With both dose levels, during the course of infection, the worm populations were mainly composed of fourth-stage larvae and worm egg excretion was low. N. spathiger mainly inhabited the proximal jejunum. The results were compared with N. spathiger infection in sheep to assess the usefulness of the rabbit as an experimental model for Nematodirus infection.     

Sympatric Breeding Auks Shift between Dietary and Spatial Resource Partitioning across the Annual Cycle

When species competing for the same resources coexist, some segregation in the way they utilize those resources is expected. However, little is known about how closely related sympatric breeding species segregate outside the breeding season. We investigated the annual segregation of three closely related seabirds (razorbill Alca torda , common guillemot Uria aalge and Brünnich’s guillemot U . lomvia ) breeding at the same colony in Southwest Greenland. By combining GPS and geolocation (GLS) tracking with dive depth and stable isotope analyses, we compared spatial and dietary resource partitioning. During the breeding season, we found the three species to segregate in diet and/or dive depth, but less in foraging area. During both the post-breeding and pre-breeding periods, the three species had an increased overlap in diet, but were dispersed over a larger spatial scale. Dive depths were similar across the annual cycle, suggesting morphological adaptations fixed by evolution. Prey choice, on the other hand, seemed much more flexible and therefore more likely to be affected by the immediate presence of potential competitors.     

Winter diet of the little auk (Alle alle) in the Northwest Atlantic

The little auk (Alle alle) is one of the most numerous seabirds in the world, but their winter prey selection has never been thoroughly studied. In the present study, we analyzed the proventricular contents of 205 little auks caught in coastal areas off southwest Greenland during December–February and off Newfoundland in March. Large Calanoid copepods are known to be the main prey during summer. We found krill to become the crucial winter prey in both areas, followed by Themisto spp. and young capelin (Mallotus villosus). No difference was found between the diet of juvenile and adult birds. Copepods constituted around 1 % of the diet and close to all copepods were in birds caught near Cape Farwell in December. These findings provide new and important insight into the forage ecology of the little auk, and they support other studies showing that large Calanoid copepods in the Arctic decent for winter hibernation at depths that are below the diving range of the little auks. More studies to determine offshore diet and annual variation are, however, needed in order to get a more complete picture.     

Proteomic Biomarkers Associated with Streptococcus agalactiae Invasive Genogroups

Group B streptococcus (GBS, Streptococcus agalactiae) is a leading cause of meningitis and sepsis in newborns and an etiological agent of meningitis, endocarditis, osteoarticular and soft tissue infections in adults. GBS isolates are routinely clustered in serotypes and in genotypes. At present one GBS sequence type (i.e. ST17) is considered to be closely associated with bacterial invasiveness and novel proteomic biomarkers could make a valuable contribution to currently available GBS typing data. For that purpose we analyzed the protein profiles of 170 genotyped GBS isolates by Surface-Enhanced Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (SELDI). Univariate statistical analysis of the SELDI profiles identified four protein biomarkers significantly discriminating ST17 isolates from those of the other sequence types. Two of these biomarkers (MW of 7878 Da and 12200 Da) were overexpressed and the other two (MW of 6258 Da and 10463 Da) were underexpressed in ST17. The four proteins were isolated by mass spectrometry-assisted purification and their tryptic peptides analyzed by LC-MS/MS. They were thereby identified as the small subunit of exodeoxyribonuclease VII, the 50S ribosomal protein L7/L12, a CsbD-like protein and thioredoxin, respectively. In conclusion, we identified four candidate biomarkers of ST17 by SELDI for high-throughput screening. These markers may serve as a basis for further studies on the pathophysiology of GBS infection, and for the development of novel vaccines.