New Data on Therangospodus oncalensis from the Berriasian Fuentesalvo Tracksite (Villar del Río,Soria, Spain): An Example of Gregarious Behaviour in Theropod Dinosaurs

Therangospodus oncalensis is a Berriasian theropod ichnotaxon from the Cameros Basin (Soria Province, Spain). We discovered new trackways assigned to this ichnotaxon during cleaning and conservation works at the type locality (Fuentesalvo), enabling us to describe it more precisely. Therangospodus oncalensis was made by a medium-sized theropod dinosaur and is characterized by a single tapering pad on each toe, a rounded heel impression and a narrow trackway. In addition to having similar morphometric characteristics, most of the trackways at the Fuentesalvo site show comparable size and biometric features. This indicates that, in terms of size and age, a homogeneous population of a single theropod species could have produced these tracks. Moreover, the similar orientation (lying within a range of only 15°) and estimated speed suggested by most of the trackways, lend weight to the hypothesis that the trackmaker of Therangospodus oncalensis was able, at least at times, to move in structured packs displaying gregarious behaviour. Furthermore, this is the first structured pack of theropods to be described.     

Biodeterioration of Mayan buildings at uxmal and tulum,Mexico

Uxmal and Tulum are two important Mayan sites in the Yucatan peninsula. The buildings are mainly composed of limestone and grey/black discoloration is seen on exposed walls and copious greenish biofilms on inner walls. The principal microorganisms detected on interior walls at both Uxmal and Tulum were cyanobacteria; heterotrophic bacteria and filamentous fungi were also present. A dark‐pigmented mitosporic fungus and Bacillus cereus, both isolated from Uxmal, were shown to be acidogenic in laboratory cultures. Cyanobacteria belonging to rock‐degrading genera Synechocystis and Gloeocapsa were identified at both sites. Surface analysis previously showed that calcium ions were present in the biofilms on buildings at Uxmal and Tulum, suggesting the deposition of biosolubilized stone. Apart from their potential to degrade the substrate, the coccoid cyanobacteria supply organic nutrients for bacteria and fungi, which can produce organic acids, further increasing stone degradation.     

Molecular data reveal cryptic lineages within the northeastern Atlantic and Mediterranean small mussel drills of the Ocinebrina edwardsii complex (Mollusca: Gastropoda: Muricidae)

We used a molecular phylogenetic approach to investigate species delimitations and diversification in the mussel drills of the Ocinebrina edwardsii complex by means of a combination of nuclear (internal transcribed spacer 2, ITS2) and mitochondrial [cytochrome oxidase subunit I (COI) and 16S] sequences. Our sample included 243 specimens ascribed to seven currently accepted species from 51 sites. Five of the samples were from either the type locality of a nominal species or a close nearby locality (O. edwardsii from Corsica, O. carmelae and O. piantonii from the Kerkennah Islands, O. hispidula from the Gulf of Gabès and O. leukos from the Canary Islands), one from the inferred original locality (O. ingloria from Venice Lagoon), and specimens assigned in the recent literature to O. nicolai. We used a combination of distance‐ and tree‐based species delimitation methods to identify Molecular Operational Taxonomic Units (MOTUs) to compare with the a priori species identifications. The consensus tree obtained by BEAST on the COI alignment allows the recognition of several distinct clades supported by the three species delimitation methods employed. The eight‐MOTUs scenario, shared by the Automatic Barcode Gap Discovery (ABGD) and Generalized Mixed Yule‐Coalescent (GMYC) methods, comprises the following major clades: clade A contains the south Tunisian species Ocinebrina piantonii Cecalupo, Buzzurro & Mariani from which the sympatric taxon O. carmelae Cecalupo, Buzzurro & Mariani (new synonym) cannot be separated; clades B and C bring together all populations from the Aegean Sea and some from the Ionian Sea, respectively; clade D groups, on the one hand, the south Tunisian samples morphologically assigned to O. hispidula Pallary and, on the other, Atlantic and Alboran Sea samples (including the Canarian taxon O. leukos Houart); clade E includes a sample from the type locality of O. edwardsii and several samples from the Tyrrhenian Sea; clades F and G correspond to a few samples from the Venice Lagoon and the Tyrrhenian Sea, respectively; clade H groups the bulk of samples from the Adriatic Sea, including samples from the Venice Lagoon morphologically identified as Ocinebrina ingloria (Crosse), and some from the Ionian Sea. No final conclusions could be reached to reconcile the currently recognized morphological taxa with the clades suggested by the COI data. The geographical structure proposed by the mitochondrial markers is similar to that found in other marine invertebrates and partially corresponds to the species defined by shell characters. We propose here a framework for the revision of the Ocinebrina edwardsii species complex, suggesting a geographical pattern for the diversification of this group in the studied area. © 2013 The Linnean Society of London     

R-Spondin2 is a secreted activator of Wnt/beta-catenin signaling and is required for Xenopus myogenesis

We have carried out a small pool expression screen for modulators of the Wnt/beta-catenin pathway and identified Xenopus R-spondin2 (Rspo2) as a secreted activator of this cascade. Rspo2 is coexpressed with and positively regulated by Wnt signals and synergizes with Wnts to activate beta-catenin. Analyses of functional interaction with components of the Wnt/beta-catenin pathway suggest that Rspo2 functions extracellularly at the level of receptor ligand interaction. In addition to activating the Wnt/beta-catenin pathway, Rspo2 overexpression blocks Activin, Nodal, and BMP4 signaling in Xenopus, raising the possibility that it may negatively regulate the TGF-beta pathway. Antisense Morpholino experiments in Xenopus embryos and RNAi experiments in HeLa cells reveal that Rspo2 is required for Wnt/beta-catenin signaling. In Xenopus embryos depleted of Rspo2, the muscle markers myoD and myf5 fail to be activated and later muscle development is impaired. Thus, Rspo2 functions in a positive feedback loop to stimulate the Wnt/beta-catenin cascade.     

Evidence for infanticide in bottlenose dolphins of the western North Atlantic

Nine bottlenose dolphin (Tursiops truncatus) calves that stranded in Virginia in 1996 and 1997 died of severe blunt-force trauma. Injuries were concentrated on the head and chest and multiple rib fractures, lung lacerations, and soft tissue contusions were prominent. Skeletal and/or soft tissue trauma occurred bilaterally in all of the calves. One had a bite wound across the left mandible that exhibited deep punctures consistent with the tooth placement in an adult bottlenose dolphin. The lesions were not compatible with predation, boat strike, fisheries interactions, rough-surf injury, or blast injury. However, they were similar to traumatic injuries described in stranded bottlenose dolphin calves and harbor porpoises (Phocoena phocoena) in Great Britain attributed to violent dolphin interactions. The evidence suggests that violent dolphin behavior was the cause of the trauma in the nine calves reported here and that infanticide occurs in bottlenose dolphins of the western North Atlantic.     

Dynamic emergence of the mesenchymal CD44CD24 phenotype in HER2-gene amplified breast cancer cells with de novo resistance to trastuzumab (Herceptin)

Evidence is mounting that the occurrence of the CD44^pos/CD24^neg/low cell population, which contains potential breast cancer (BC) stem cells, could explain BC clinical resistance to HER2-targeted therapies. We investigated whether de novo refractoriness to the anti-HER2 monoclonal antibody trastuzumab (Tzb; Herceptin) may relate to the dynamic regulation of the mesenchymal CD44^pos/CD24^neg/low phenotype in HER2-positive BC. We observed that the subpopulation of Tzb-refractory JIMT-1 BC cells exhibiting CD44^pos/CD24^neg/low-surface markers switched with time. Low-passage JIMT-1 cell cultures were found to spontaneously contain ∼10% of cells bearing the CD44^pos/CD24^neg/low immunophenotype. Late-passage (>60) JIMT-1 cultures accumulated ∼80% of CD44^pos/CD24^neg/low cells and closely resembled the CD44^pos/CD24^neg/low-enriched (∼85%) cell population constitutively occurring in HER2-negative MDA-MB-231 mesenchymal BC cells. Dynamic expression of mesenchymal markers was not limited to CD44/CD24 because high-passages of JIMT-1 cells exhibited also reduced expression of the HER2 protein and over-secretion of pro-invasive/metastatic chemokines and metalloproteases. Accordingly, late-passage JIMT-1 cells displayed an exacerbated migratogenic phenotype in plastic, collagen, and fibronectin substrates. Intrinsic genetic plasticity to efficiently drive the emergence of the CD44^pos/CD24^neg/low mesenchymal phenotype may account for de novo resistance to HER2 targeting therapies in basal-like BC carrying HER2 gene amplification.     

Mariprofundus ferrooxydans PV-1 the first genome of a marine Fe(II) oxidizing Zetaproteobacterium

Mariprofundus ferrooxydans PV-1 has provided the first genome of the recently discovered Zetaproteobacteria subdivision. Genome analysis reveals a complete TCA cycle, the ability to fix CO(2), carbon-storage proteins and a sugar phosphotransferase system (PTS). The latter could facilitate the transport of carbohydrates across the cell membrane and possibly aid in stalk formation, a matrix composed of exopolymers and/or exopolysaccharides, which is used to store oxidized iron minerals outside the cell. Two-component signal transduction system genes, including histidine kinases, GGDEF domain genes, and response regulators containing CheY-like receivers, are abundant and widely distributed across the genome. Most of these are located in close proximity to genes required for cell division, phosphate uptake and transport, exopolymer and heavy metal secretion, flagellar biosynthesis and pilus assembly suggesting that these functions are highly regulated. Similar to many other motile, microaerophilic bacteria, genes encoding aerotaxis as well as antioxidant functionality (e.g., superoxide dismutases and peroxidases) are predicted to sense and respond to oxygen gradients, as would be required to maintain cellular redox balance in the specialized habitat where M. ferrooxydans resides. Comparative genomics with other Fe(II) oxidizing bacteria residing in freshwater and marine environments revealed similar content, synteny, and amino acid similarity of coding sequences potentially involved in Fe(II) oxidation, signal transduction and response regulation, oxygen sensation and detoxification, and heavy metal resistance. This study has provided novel insights into the molecular nature of Zetaproteobacteria.     

The acute asymmetric effects of hemiovariectomy on testosterone secretion vary along the estrous cycle. The participation of the cholinergic system

The presence of asymmetry in the capacity of the left and right ovaries to secrete testosterone was analyzed by studying the effects of hemiovariectomy along the estrus cycle one hour after surgery. The effects of ether anesthesia on hormone serum levels were also analyzed.     

REHABILITATION AND RELEASE OF MARINE MAMMALS IN THE UNITED STATES: RISKS AND BENEFITS

Rehabilitation of stranded marine mammals elicits polarized attitudes: initially done alongside display collections, but release of rehabilitated animals has become more common. Justifications include animal welfare, management of beach use conflict, research, conservation, and public education. Rehabilitation cost and risks have been identified that vary in degree supported by data rather than perception. These include conflict with fisheries for resources, ignorance of recipient population ecology, poor understanding of long-term survival, support of the genetically not-so-fit, introduction of novel or antibiotic-resistant pathogens, harm to human health, and cost. Thus facilities must balance their welfare appeal against public education, habitat restoration, human impact reduction, and other conservation activities. Benefits to rehabilitating marine mammals are the opportunity to support the welfare of disabled animals and to publish good science and so advance our understanding of wild populations. In specific cases, the status of a population may make conservation the main reason for rehabilitation. These three reasons for rehabilitation lead to contrasting, and sometimes conflicting, management needs. We therefore outline a decision tree for rehabilitation managers using criteria for each management decision, based on welfare, logistics, conservation, research, and funding to define limits on the number of animals released to the wild.