Vaccination with recombinant alphavirus or immune-stimulating complex antigen against respiratory syncytial virus

Respiratory syncytial virus (RSV) causes severe respiratory diseases in infants and young children. Inappropriate immunity to the virus can lead to disease enhancement upon subsequent infection. In this study, we have characterized the antiviral immunity elicited by the recombinant Semliki Forest virus (SFV) encoding the RSV fusion (F) and attachment (G) protein, and compared with that induced by the immune-stimulating complex (ISCOM)-incorporated FG proteins. Antiviral immunity against RSV elicited nasally or parentally by either of the immunogen having divergent profiles could reduce lung RSV titers upon challenge. However, resistance to RSV without disease enhancement was only observed in those vaccinated with SFV recombinants via nasal route. Presence of postvaccination pulmonary IFN-gamma response to the H-2K(d)-restricted T cell epitope (F(85-93); KYKNAVTEL) was found to be associated with absence of enhanced pulmonary disease and goblet cell hyperplasia as well as reduced Th2-cytokine expression. This result demonstrates that the SFV recombinants can result in enhanced clearance of RSV without enhancing the RSV-associated disease, and underlines the importance in priming pulmonary MHC class I-restricted T cells when RSV FG-based vaccines are used.     

Differences in growth between offspring of anadromous and freshwater brown trout Salmo trutta

In this study, individual growth of juvenile offspring of anadromous and freshwater resident brown trout Salmo trutta and crosses between the two from the River Imsa, Norway, was estimated. The juveniles were incubated until hatching at two temperatures (±S.D. ), either 4.4 ± 1.5°C or 7.1 ± 0.6°C. Growth rate was estimated for 22 days in August–September when the fish on average were c. 8 g in wet mass, and the estimates were standardized to 1 g fish dry mass. Offspring of anadromous S. trutta grew better at both 15 and 18°C than offspring of freshwater resident S. trutta or offspring of crosses between the two S. trutta types. This difference appears not to result from a maternal effect because anadromous S. trutta grew better than the hybrids with anadromous mothers. Instead, this appears to be an inherited difference between the anadromous and the freshwater resident fish lending support to the hypothesis that anadromous and freshwater resident S. trutta in this river differ in genetic expression. Egg incubation temperature of S. trutta appeared not to influence the later growth as reported earlier from the studies of Atlantic salmon Salmo salar.     

Projected free fall trajectories

We are very adept at using the purely two-dimensional information we get from our retinae to manoever and react to the three-dimensional world: witness the tennis player returning a 100 mph serve. In another article (Saxberg 1987) we have shown how gravity can in theory be used as a constraint to determine the initial conditions of a three-dimensional free fall trajectory from the two-dimensional central projection of the trajectory. We have developed a simple video game to investigate what information is important to humans trying to solve a problem of this sort: predicting where a ball will fall. We show that humans do not seem to use the trajectory information suggested by the theoretical results in (Saxberg 1985), but rely on other sources of information, such as the size of the image on the projection surface.     

Interactions between immune-stimulating complexes (ISCOMs) and peritoneal mononuclear leucocytes.

Studies were undertaken in mice using immune-stimulating complexes (ISCOMs) or micelles prepared from envelope glycoproteins of human influenza virus (PR8) and matrix (i.e., ISCOM skeleton without incorporated antigen). Electron microscopic studies showed that ISCOMs, in contrast to micelles, have a remarkable affinity for cell membranes and seem to rapidly promote their own internalization by cells to which they adhere. PR8 ISCOMs, but not matrix nor micelles, significantly increased the expression of membrane Ia by peritoneal mononuclear leucocytes 24 hr after intraperitoneal immunization.     

Deep phylogeographic splits and limited mixing by sea surface currents govern genetic population structure in the mangrove genus Lumnitzera (Combretaceae) across the Indonesian Archipelago

The Indonesian Archipelago accommodates the largest mangrove area in Southeast Asia and possesses the world's richest composition of mangrove species. The archipelago comprises areas of the biogeographic regions Sunda and Wallacea, separated by Wallace's line. Here, we used the true mangrove species Lumnitzera littorea and Lumnitzera racemosa as a study case for understanding the effects of phylogeographic history, sea surface currents, and geographical distance on genetic diversity and genetic structure. We sampled 14 populations of L. littorea (N = 106) and 21 populations of L. racemosa (N = 152) from Indonesia and used 3122 and 3048 SNP loci, respectively, genotyped using the ddRADseq approach. We assessed genetic diversity, genetic structure, and effective dispersal of the populations and related them to geographical distance and sea surface currents. Our study revealed low levels of genetic variation at the population level in Lumnitzera. Pronounced genetic differentiation between populations indicated two phylogroups in both species. While in L. littorea the two phylogroups were largely separated by Wallace's line, L. racemosa showed a northwest vs. southeast pattern with strong mixture in Wallacea. Our findings provide novel insights into the phylogeography of the mangrove genus Lumnitzera and the role of sea surface currents in the Indonesian Archipelago.     

Projected free fall trajectories

How we manage to reconstruct the three-dimensional character of the world from the two-dimensional representations on our retinae has been a lively subject of research in the last ten or fifteen years. One principle that has emerged unifying many of these ideas is the need for constraints to allow the visual system to interpret the images it receives as three-dimensional. These constraints come from assumptions about the nature of the situation that produced the image. We have looked at how gravity can be used as a constraint in the case of a free fall trajectory projected onto an image plane by central projection. We have examined several possible methods for deriving the initial conditions of the trajectory from the two-dimensional projection, and examined their behavior under noisy and noiseless conditions, using both image simulations and videotapes of a real ball. We show that there are several ways to robustly compute the initial conditions of the parabolic trajectory from the image data in the presence of noise.     

Continuous outmigration and sequential encountering of environmental cues are important for successful homing of hatchery-reared,anadromous brown trout Salmo trutta

When rehabilitating and reintroducing trout Salmo trutta in rivers, it is a goal that as many as possible survive, home and form self-sustaining populations. Hatchery-reared, anadromous S. trutta have significant lower ability to return to the area where they were raised if (a) transported in a closed tank to sea and released 5 km from the River Imsa, relative to those that were (b) transported when swimming in a partly submerged tank with sea water run-through, while being slowly towed by a boat the same distance or (c) released at the outlet of the River Imsa. Thus, if deprived from environmental cues during part of the way, they lose their ability to home.