Behavior of adult and young grassland songbirds at fledging

The behavior of adults and young at the time of fledging is one of the least understood aspects of the breeding ecology of birds. Current hypotheses propose that fledging occurs either as a result of parent‐offspring conflict or nestling choice. We used video recordings to monitor the behavior of nestling and adult grassland songbirds at the time of fledging. We observed 525 nestlings from 166 nests of 15 bird species nesting in grasslands of Alberta, Canada, and Wisconsin, USA. Overall, 78% of nestlings used terrestrial locomotion for fledging and 22% used wing‐assisted locomotion. Species varied in propensity for using wing‐assisted locomotion when fledging, with nestling Grasshopper Sparrows (Ammodramus savannarum) and Henslow's Sparrows (Centronyx henslowii) often doing so (47% of fledgings) and nestling Song Sparrows (Melospiza melodia), Common Yellowthroats (Geothlypis trichas), and Chestnut‐collared Longspurs (Calcarius ornatus) rarely doing so (3.5% of fledgings). For 390 fledging events at 127 nests, camera placement allowed adults near nests to be observed. Of these, most young fledged (81.5%) when no adult was present at nests. Of 72 fledging events that occurred when an adult was either at or approaching a nest, 49 (68.1%) involved feeding. Of those 49 fledgings, 30 (62.1%) occurred when one or more nestlings jumped or ran from nests to be fed as an adult approached nests. The low probability of nestlings fledging while an adult was at nests, and the tendency of young to jump or run from nests when adults did approach nests with food minimize opportunities for parents to withhold food to motivate nestlings to fledge. These results suggest that the nestling choice hypothesis best explains fledging by nestlings of ground‐nesting grassland songbirds, and fledging results in families shifting from being place‐based to being mobile and spatially dispersed.     

Multiple sclerosis: urinary amine measurement for orthomolecular diagnosis

Urinary amines from 53 people who have multiple sclerosis and 58 controls have been separated and measured quantitatively by means of low-resolution ion-exchange procedure. Dependences on multiple sclerosis and on sex have been detected. The multiple-sclerosis-dependent pattern has been tested for diagnostic value by means of the weighted non-correlation index method.     

The ecology of Belizean mangrove-root fouling communities: patterns of epibiont distribution and abundance,and effects on root growth

The aerial prop roots of the neotropical red mangrove,Rhizophora mangle L., begin growing well above highest high water (HHW) and often extend well below lowest low water (LLW) before rooting in the benthic substratum. In Belize, Central America, prop roots growing below LLW are colonized by diverse assemblages of organisms, including macroalgae, hydrozoans, ascidians, sponges, anemones, hard corals, and isopod crustaceans. Mangroves, root-fouling epibionts, root herbivores, and benthic predators engage in complex interactions that are major determinants of mangrove growth and production. Species richness of root epibionts increases with distance from the mainland and with proximity to the barrier reef. Species richness decreases with variability in water temperature and salinity. Ascidians and sponges transplanted from Lark Cay into the coastal Placencia Lagoon failed to survive, but anemones from Lark Cay survived in Placencia Lagoon. Reciprocal transplants survived off-shore. The gastropod predator,Melongena melongena L., present only in mainland estuaries, reduced local barnacle abundance and epibiont species richness in Placencia Lagoon. Isopod species richness also increases with distance from shore, but the number of roots bored by these species decreases. These isopods can reduce root relative growth rate (RGR_root) by 55%. On off-shore cays, sponges and ascidians ameliorate negative effects of isopods. In mainland estuaries where epibionts are less common, isopod damage to roots is more severe. Experimental studies in mangrove swamps throughout the world would clarify the importance of plant-animal interactions in these widespread tropical ecosystems.     

The β3‐integrin endothelial adhesome regulates microtubule‐dependent cell migration

Integrin β3 is seen as a key anti‐angiogenic target for cancer treatment due to its expression on neovasculature, but the role it plays in the process is complex; whether it is pro‐ or anti‐angiogenic depends on the context in which it is expressed. To understand precisely β3's role in regulating integrin adhesion complexes in endothelial cells, we characterised, by mass spectrometry, the β3‐dependent adhesome. We show that depletion of β3‐integrin in this cell type leads to changes in microtubule behaviour that control cell migration. β3‐integrin regulates microtubule stability in endothelial cells through Rcc2/Anxa2‐driven control of active Rac1 localisation. Our findings reveal that angiogenic processes, both in vitro and in vivo, are more sensitive to microtubule targeting agents when β3‐integrin levels are reduced.     

Substrate selectivity and sensitivity to inhibition by FK506 and cyclosporin A of calcineurin heterodimers composed of the alpha or beta catalytic subunit.

The calcineurin (CaN) alpha and beta catalytic subunit isoforms are coexpressed within almost all cell types. The enzymatic properties of CaN heterodimers comprised of the regulatory B subunit (CnB) with either the alpha or beta catalytic subunit were compared using in vitro phosphatase assays. CaN containing the alpha isoform (CnA alpha) has lower K(m) and higher V(max) values than CaN containing the beta isoform (CnA beta) toward the PO4-RII, PO4-DARPP-32(20-38) peptides, and p-nitrophenylphosphate (pNPP). CaN heterodimers containing the alpha or beta catalytic subunit isoform displayed identical calmodulin dissociation rates. Similar inhibition curves for each CaN heterodimer were obtained with the CaN autoinhibitory peptide (CaP) and cyclophilin A/cyclosporin A (CyPA/CsA) using each peptide substrate at K(m) concentrations, except for a five- to ninefold higher IC50 value measured for CaN containing the beta isoform with p-nitrophenylphosphate as substrate. No difference in stimulation of phosphatase activity toward p-nitrophenylphosphate by FKBP12/FK506 was observed. At low concentrations of FKBP12/FK506, CaN containing the alpha isoform is more sensitive to inhibition than CaN containing the beta isoform using the phosphopeptide substrates. Higher concentrations of FKBP12/FK506 are required for maximal inhibition of beta CaN using PO4-DARPP-32(20-38) as substrate. The functional differences conferred upon CaN by the alpha or beta catalytic subunit isoforms suggest that the alpha:beta and CaN:substrate ratios may determine the levels of CaN phosphatase activity toward specific substrates within tissues and specific cell types. These findings also indicate that the alpha and beta catalytic subunit isoforms give rise to substrate-dependent differences in sensitivity toward FKBP12/FK506.