Molecular phylogeny of songbirds (Aves: Passeriformes) and the relative utility of common nuclear marker loci

While the monophyly of the largest avian order Passeriformes as well as its suborders suboscines (Tyranni) and oscines (Passeri) is well established, lower phylogenetic relationships of this fast radiated taxon have been a continuous matter of debate, especially within the suborder oscines. Many studies analyzing phylogenetic relationships of the Passeriformes using molecular markers have been published, which led to a better resolved phylogeny. Conflicting hypotheses and still remaining uncertainties, especially within the Passerida, have repeatedly stimulated further research with additional new markers. In the present study we used a combination of established molecular markers (RAG‐1, RAG‐2, c‐myc) and the recently introduced ZENK. We accomplished phylogenetic analyses using maximum parsimony, maximum likelihood and Bayesian inference, both separately for all genes and simultaneously. To assess the phylogenetic utility of the different genes in avian systematics we analyzed the influence of each data partition on the phylogenetic tree yielded by the combined approach using partitioned Bremer support. Compared with the other single gene analyses, the ZENK trees exhibited by far the best resolution and showed the lowest amount of homoplasy. Our data indicate that this gene is—at least in passerines—suitable for inference of even old taxonomic splits. Our combined analysis yields well‐supported phylogenetic hypotheses for passerine phylogeny and apart from corroborating recently proposed hypotheses on phylogenetic relationships in the Passeriformes we provide evidence for some new hypotheses. The subdivision of the Passerida into three superfamilies, Sylvioidea, Passeroidea and Muscicapoidea, the first as sister to the two latter groups is strongly supported. We found evidence for a split between Paridae and the remaining Sylvioidea. © The Willi Hennig Society 2007.     

Edge Effects Are Important in Supporting Beetle Biodiversity in a Gravel-Bed River Floodplain

Understanding complex, dynamic, and diverse ecosystems is essential for developing sound management and conservation strategies. Gravel-bed river floodplains are composed of an interlinked mosaic of aquatic and terrestrial habitats hosting a diverse, specialized, and endangered fauna. Therefore, they serve as excellent models to investigate the biodiversity of multiple ecotones and related edge effects. In this study, we investigated the abundance, composition, richness, and conservation status of beetle assemblages at varying sediment depth (0, 0.1, 0.6 and 1.1 m), distance from the channel (1, 5, 20, and 60–100 m, and 5 m within the riparian forest), and time of the year (February–November) across a 200 m-wide gravel bar at the near-natural Tagliamento River (Italy), to detect edge effects in four floodplain ecotones: aquatic-terrestrial, forest-active floodplain, sediment-air, and sediment-groundwater. We used conventional pitfall traps and novel tube traps to sample beetles comparably on the sediment surface and within the unsaturated sediments. We found a total of 308 beetle species (including 87 of conservation concern) that showed multiple, significant positive edge effects across the floodplain ecotones, mainly driven by spatial heterogeneity: Total and red list beetle abundance and richness peaked on the sediment surface, at channel margins, and at the edge of the riparian forest. All ecotones possessed edge/habitat specialists. Most red list species occurred on the sediment surface, including five species previously considered extinct – yet two of these species occurred in higher densities in the unsaturated sediments. Conservation and management efforts along gravel-bed rivers must therefore promote a dynamic flow and sediment regime to create and maintain habitat heterogeneity and ecotone diversity, which support a unique and high biodiversity.     

Specific calpain activity evaluation in Plasmodium parasites

In the intraerythrocytic trophozoite stages of Plasmodium falciparum, the calcium-dependent cysteine protease calpain (Pf-calpain) has an important role in the parasite calcium modulation and cell development. We established specific conditions to follow by confocal microscopy and spectrofluorimetry measurements the intracellular activity of Pf-calpain in live cells. The catalytic activity was measured using the fluorogenic Z-Phe-Arg-MCA (where Z is carbobenzoxy and MCA is 4-methylcoumaryl-7-amide). The calmodulin inhibitor calmidazolium and the sarcoplasmic reticulum calcium ATPase inhibitor thapsigargin were used for modifications in the cytosolic calcium concentrations that persisted in the absence of extracellular calcium. The observed calcium-dependent peptidase activity was greatly inhibited by specific cysteine protease inhibitor E-64 and by the selective calpain inhibitor ALLN (N-acetyl-l-leucyl-l-leucyl-l-norleucinal). Taken together, we observed that intracellular Pf-calpain can be selectively detected and is the main calcium-dependent protease in the intraerythrocytic stages of the parasite. The method described here can be helpful in cell metabolism studies and antimalarial drug screening.     

Agricultural resources in the Bronze Age city of Tel Lachish

Vegetation History and Archaeobotany - In this paper, we present the results of the plant macrofossil analyses from the site of Tel Lachish, Israel with focus on the botanical assemblage of the...     

Identification of MK-5710 ((8aS)-8a-methyl-1,3-dioxo-2-[(1S,2R)-2-phenylcyclo- propyl]-N-(1-phenyl-1H-pyrazol-5-yl)hexahydro-imidazo[1,5-a]pyrazine-7(1H)-carboxamide), a potent smoothened antagonist for use in Hedgehog pathway dependent malignancies, part 2

The Hedgehog (Hh-) signaling pathway is a key developmental pathway which gets reactivated in many human tumors, and smoothened (Smo) antagonists are emerging as novel agents for the treatment of malignancies dependent on the Hh-pathway, with the most advanced compounds demonstrating encouraging results in initial clinical trials. A novel series of potent bicyclic hydantoin Smo antagonists was reported in the preceding article, these have been resolved, and optimized to identify potent homochiral derivatives with clean off-target profiles and good pharmacokinetic properties in preclinical species. While showing in vivo efficacy in mouse allograft models, unsubstituted bicyclic tetrahydroimidazo[1,5-a]pyrazine-1,3(2H,5H)-diones were shown to epimerize in plasma. Alkylation of the C-8 position blocks this epimerization, resulting in the identification of MK-5710 (47) which was selected for further development.