Evolutionary history and identification of conservation units in the giant otter, Pteronura brasiliensis.

The giant otter, Pteronura brasiliensis, occupies a range including the major drainage basins of South America, yet the degree of structure that exists within and among populations inhabiting these drainages is unknown. We sequenced portions of the mitochondrial DNA (mtDNA) cytochrome b (612 bp) and control region (383 bp) genes in order to determine patterns of genetic variation within the species. We found high levels of mtDNA haplotype diversity (h = 0.93 overall) and support for subdivision into four distinct groups of populations, representing important centers of genetic diversity and useful units for prioritizing conservation within the giant otter. We tested these results against the predictions of three hypotheses of Amazonian diversification (Pleistocene Refugia, Paleogeography, and Hydrogeology). While the phylogeographic pattern conformed to the predictions of the Refugia Hypothesis, molecular dating using a relaxed clock revealed the phylogroups diverged from one another between 1.69 and 0.84 Ma, ruling out the influence of Late Pleistocene glacial refugia. However, the role of Plio-Pleistocene climate change could not be rejected. While the molecular dating also makes the influence of geological arches according to the Paleogeography Hypothesis extremely unlikely, the recent Pliocene formation of the Fitzcarrald Arch and its effect of subsequently altering drainage pattern could not be rejected. The data presented here support the interactions of both climatic and hydrological changes resulting from geological activity in the Plio-Pleistocene, in shaping the phylogeographic structure of the giant otter

Mannose-Specific Lectins from Marine Algae: Diverse Structural Scaffolds Associated to Common Virucidal and Anti-Cancer Properties.

To date, a number of mannose-specific lectins have been isolated and characterized from seaweeds, especially from red algae. In fact, man-specific seaweed lectins consist of different structural scaffolds harboring a single or a few carbohydrate-binding sites which specifically recognize mannose-containing glycans. Depending on the structural scaffold, man-specific seaweed lectins belong to five distinct structurally-related lectin families, namely (1) the griffithsin lectin family (beta-prism I scaffold); (2) the Oscillatoria agardhii agglutinin homolog (OAAH) lectin family (beta-barrel scaffold); (3) the legume lectin-like lectin family (beta-sandwich scaffold); (4) the Galanthus nivalis agglutinin (GNA)-like lectin family (beta-prism II scaffold); and, (5) the MFP2-like lectin family (MFP2-like scaffold). Another algal lectin from Ulva pertusa, has been inferred to the methanol dehydrogenase related lectin family, because it displays a rather different GlcNAc-specificity. In spite of these structural discrepancies, all members from the five lectin families share a common ability to specifically recognize man-containing glycans and, especially, high-mannose type glycans. Because of their mannose-binding specificity, these lectins have been used as valuable tools for deciphering and characterizing the complex mannose-containing glycans from the glycocalyx covering both normal and transformed cells, and as diagnostic tools and therapeutic drugs that specifically recognize the altered high-mannose N-glycans occurring at the surface of various cancer cells. In addition to these anti-cancer properties, man-specific seaweed lectins have been widely used as potent human immunodeficiency virus (HIV-1)-inactivating proteins, due to their capacity to specifically interact with the envelope glycoprotein gp120 and prevent the virion infectivity of HIV-1 towards the host CD4+ T-lymphocyte cells in vitro

Non-Indigenous Cladocera (Crustacea: Branchiopoda): From a Few Notorious Cases to a Potential Global Faunal Mixing in Aquatic Ecosystems

Non-indigenous species may pose a threat to native ecosystems worldwide. In aquatic environments, invasives may have a negative impact on human food security and livelihoods. Several water fleas (Crustacea: Branchiopoda: Cladocera) are notorious invasive alien species influencing large freshwater lake systems and even inland seas. In the current review, we discuss the state of knowledge regarding non-indigenous species in the Cladocera and their invasiveness potential in different continents. We argue that the potential impacts and occurrence of cladoceran exotics may be higher than generally assumed. We critically review 79 cases from literature sources, involving 61 cladoceran taxa where records outside of their natural distribution ranges were previously interpreted as invasions. We assessed the probability of natural range expansions versus human-mediated introductions and we discuss several major corridors of invasion. We estimate human-mediated transportations for at least 43 taxa (out of 61; ca 70%), while other cases can be seen as natural expansions of their distribution ranges (not necessarily/not likely human-mediated) and/or taxonomical confusion. We confirm non-indigenous presence in recipient regions for at least 41 cladoceran taxa, of which several are true invasives (i.e., with negative impacts on native ecosystems). The majority are zooplankters with effects on pelagic freshwater ecosystems, yet we also report on introductions by littoral taxa. We argue that cryptic introductions of cladocerans are taking place on a global scale, yet they remain under the radar. We highlight several striking case studies, such as the Ponto-Caspian onychopods that have invaded the Baltic Sea and the Laurentian Great Lakes, and several clones of the anomopod genera Daphnia and Bosmina that have successfully colonised new environments, causing equilibria shifts in native aquatic worlds. At the same time, we dispel some myths about taxa that were misconstrued as invasive in certain localities. Based on our review, the first of its kind for freshwater zooplankton, future environmental monitoring tools including molecular techniques and detailed surveys with rigorous and critical taxonomical assessments may help to provide a clearer picture on the extent of invasiveness of cladocerans.O

Distraction from pain and executive functioning: an experimental investigation of the role of inhibition, task switching and working memory

Although many studies have investigated the effectiveness of distraction as a method of pain control, the cognitive processes by which attentional re-direction is achieved, remain unclear. In this study the role of executive functioning abilities (inhibition, task switching and working memory) in the effectiveness of distraction is investigated. We hypothesized that the effectiveness of distraction in terms of pain reduction would be larger in participants with better executive functioning abilities. Ninety-one undergraduate students first performed executive functioning tasks, and subsequently participated in a cold pressor task (CPT). Participants were randomly assigned to (1) a distraction group, in which an attention-demanding tone-detection task was performed during the CPT, or (2) a control group, in which no distraction task was performed. Participants in the distraction group reported significantly less pain during the CPT, but the pain experience was not influenced by executive functioning abilities. However, the performance on the distraction task improved with better inhibition abilities, indicating that inhibition abilities might be important in focussing on a task despite the pain

Ecological study of some parasitic helminths of aquatic organisms

Except for Monogenea, most other helminth parasites (Digenea, Cestoda, Nematoda and Acanthocephala) of aquatic organisms have a rather complex life cycle, which includes one or more intermediate hosts. Studies have been carried out on the elucidation of helminth life cycles and on parasite-host relationships. Knowledge of the feeding behaviour of the host is a very useful starting-point for elucidation of the life cycles of its' parasites. Asymphylodora demeli, a trematode of two sympatric gobies (Pomatoschistus minutus and P. lozanoi) of the Belgian coastal waters, has been studied. Although very abundant, the life cycle of this parasite remains unsolved. During the summer, the percentage of infection is the same for both Pomatoschistus populations, but the infection level is remarkably higher for P. minutus. Some invertebrates, which are important food items for the Pomatoschistus species, are proposed as potential intermediate hosts. It has become clear that special attention has to be paid on the role of Mollusca in the life cycle of A. demeli. The impact of parasites on lenght-weight relationship, gonadosomatic and hepatosomatic index of their hosts is studied

Do tonic itch and pain stimuli draw attention towards their location?

Background. Although itch and pain are distinct experiences, both are unpleasant, may demand attention, and interfere with daily activities. Research investigating the role of attention in tonic itch and pain stimuli, particularly whether attention is drawn to the stimulus location, is scarce. Methods. In the somatosensory attention task, fifty-three healthy participants were exposed to 35-second electrical itch or pain stimuli on either the left or right wrist. Participants responded as quickly as possible to visual targets appearing at the stimulated location (ipsilateral trials) or the arm without stimulation (contralateral trials). During control blocks, participants performed the visual task without stimulation. Attention allocation at the itch and pain location is inferred when responses are faster ipsilaterally than contralaterally. Results. Results did not indicate that attention was directed towards or away from the itch and pain location. Notwithstanding, participants were slower during itch and pain than during control blocks. Conclusions. In contrast with our hypotheses, no indications were found for spatial attention allocation towards the somatosensory stimuli. This may relate to dynamic shifts in attention over the time course of the tonic sensations. Our secondary finding that itch and pain interfere with task performance is in-line with attention theories of bodily perception