Stable isotopes in fossil hominin tooth enamel suggest a fundamental dietary shift in the Pliocene

Accumulating isotopic evidence from fossil hominin tooth enamel has provided unexpected insights into early hominin dietary ecology. Among the South African australopiths, these data demonstrate significant contributions to the diet of carbon originally fixed by C₄ photosynthesis, consisting of C₄ tropical/savannah grasses and certain sedges, and/or animals eating C₄ foods. Moreover, high-resolution analysis of tooth enamel reveals strong intra-tooth variability in many cases, suggesting seasonal-scale dietary shifts. This pattern is quite unlike that seen in any great apes, even ‘savannah’ chimpanzees. The overall proportions of C₄ input persisted for well over a million years, even while environments shifted from relatively closed (ca 3 Ma) to open conditions after ca 1.8 Ma. Data from East Africa suggest a more extreme scenario, where results for Paranthropus boisei indicate a diet dominated (approx. 80%) by C₄ plants, in spite of indications from their powerful ‘nutcracker’ morphology for diets of hard objects. We argue that such evidence for engagement with C₄ food resources may mark a fundamental transition in the evolution of hominin lineages, and that the pattern had antecedents prior to the emergence of Australopithecus africanus. Since new isotopic evidence from Aramis suggests that it was not present in Ardipithecus ramidus at 4.4 Ma, we suggest that the origins lie in the period between 3 and 4 Myr ago.     

Characterization of an anti-lymphocyte function-associated antigen-1 antibody in a simian immunodeficiency virus-pig-tailed macaque (Macaca nemestrina) model

The simian immunodeficiency virus (SIV)/pig-tailed macaque (Macaca nemestrina) model of acquired immune deficiency syndrome (AIDS) is a powerful system in which to study cell adhesion molecules and retroviral pathogenesis in vivo. Preliminary experiments were conducted to examine the role of lymphocyte function-associated antigen 1 (LFA-1) in early SIV infection in vivo by using an LFA-1 monoclonal antibody (MHM.23) specific to human LFA-1. In vitro studies revealed that at concentrations of > or = 20 microg/ml, MHM.23 blocked LFA-1-mediated adhesion and T-cell activation (>90%) of pig-tailed macaque peripheral blood mononuclear cells (PBMCs). In addition, SIVmac239 infection of macaque cells was inhibited in a dose-dependant manner by MHM.23. Administration of MHM.23 to pig-tailed macaques inhibited LFA-1-ICAM-1-mediated activity in vivo and maintained binding on macaque cells for < or = 4 d. Our in vitro studies indicated that at an MHM.23 concentration of 20 microg/ml, macaque PBMCs were completely saturated. Our in vivo studies determined that 5 mg/kg MHM.23 intravenously every 24 h was required to maintain saturating levels and inhibit LFA-1-ICAM-1 function in pig-tailed macaques.     

Distribution and morphology of the ampullary organs of the estuarine long-tailed catfish, <Emphasis Type="Italic">Euristhmus lepturus</Emphasis> (Plotosidae,Siluriformes)

Ampullary organs of Euristhmus lepturus occur in high densities along the head and in four parallel pathways along the trunk of the body. Large ampullary pores (125–130 μm) are easily distinguishable from other sensory epithelial pores due to the differences in size and the presence of a collar-like structure. Simple, singular ampullary organs of the head region consist of an ampullary pore connected to a long canal with a diameter of 115–175 μm before terminating as a simple ampulla with an external diameter of 390–480 μm. The ampullary canal is composed of 1–2 layers of flattened squamous epithelial cells, the basement membrane and an interlocking collagen sheath. The innermost cells lining the canal wall are adjoined via tight junctions and numerous desmosomes, as are those of the receptor and supportive cells. Canal wall tissue gives rise to a sensory epithelium containing between 242 and 285 total receptor cells, with an average diameter of 11.7 ± 5.3 μm, intermixed with medially nucleated supportive cells. Each receptor cell (21.38 ± 4.41 μm, height) has an apically positioned nucleus and a luminal surface covered with numerous microvilli. Neural terminals abut the basal region of receptor cells opposite multiple presynaptic bodies and dense mitochondria. Supportive cells extend from the ampullary lumen to the basement membrane, which is adjacent to the complex system of collagen fibres.     

8-plex quantitation of changes in cerebrospinal fluid protein expression in subjects undergoing intravenous immunoglobulin treatment for Alzheimer's disease

An 8-plex version of an isobaric reagent for the quantitation of proteins using shotgun methods is presented. The 8-plex version of the reagent relies on amine-labeling chemistry of peptides similar to 4-plex reagents. MS/MS reporter ions at 113, 114, 115, 116, 117, 118, 119, and 121 m/z are used to quantify protein expression. This technology which was first applied to a test mixture consisting of eight proteins and resulted in accurate quantitation, has the potential to increase throughput of analysis for quantitative shotgun proteomics experiments when compared to 2- and 4-plex methods. The technology was subsequently applied to a longitudinal study of cerebrospinal fluid (CSF) proteins from subjects undergoing intravenous Ig treatment for Alzheimer's disease. Results from this study identify a number of protein expression changes that occur in CSF after 3 and 6 months of treatment compared to a baseline and compared to a drug washout period. A visualization tool was developed for this dataset and is presented. The tool can aid in the identification of key peptides and measurements. One conclusion aided by the visualization tool is that there are differences in considering peptide-based observations versus protein-based observations from quantitative shotgun proteomics studies.     

Cyclooxygenase-1 overexpression decreases Basal airway responsiveness but not allergic inflammation

Pharmacological inhibition or genetic disruption of cyclooxygenase (COX)-1 or COX-2 exacerbates the inflammatory and functional responses of the lung to environmentally relevant stimuli. To further examine the contribution of COX-derived eicosanoids to basal lung function and to allergic lung inflammation, transgenic (Tr) mice were generated in which overexpression of human COX-1 was targeted to airway epithelium. Although no differences in basal respiratory or lung mechanical parameters were observed, COX-1 Tr mice had increased bronchoalveolar lavage fluid PGE(2) content compared with wild-type littermates (23.0 +/- 3.6 vs 8.4 +/- 1.4 pg/ml; p < 0.05) and exhibited decreased airway responsiveness to inhaled methacholine. In an OVA-induced allergic airway inflammation model, comparable up-regulation of COX-2 protein was observed in the lungs of allergic wild-type and COX-1 Tr mice. Furthermore, no genotype differences were observed in allergic mice in total cell number, eosinophil content (70 vs 76% of total cells, respectively), and inflammatory cytokine content of bronchoalveolar lavage fluid, or in airway responsiveness to inhaled methacholine (p > 0.05). To eliminate the presumed confounding effects of COX-2 up-regulation, COX-1 Tr mice were bred into a COX-2 null background. In these mice, the presence of the COX-1 transgene did not alter allergen-induced inflammation but significantly attenuated allergen-induced airway hyperresponsiveness, coincident with reduced airway leukotriene levels. Collectively, these data indicate that COX-1 overexpression attenuates airway responsiveness under basal conditions but does not influence allergic airway inflammation.     

Scalable purification of Bacillus anthracis protective antigen from Escherichia coli

The anthrax toxin consists of three proteins, protective antigen (PA), lethal factor, and edema factor that are produced by the Gram-positive bacterium, Bacillus anthracis. Current vaccines against anthrax use PA as their primary component. In this study, we developed a scalable process to produce and purify multi-gram quantities of highly pure, recombinant PA (rPA) from Escherichia coli. The rPA protein was produced in a 50-L fermentor and purified to >99% purity using anion-exchange, hydrophobic interaction, and hydroxyapatite chromatography. The final yield of purified rPA from medium cell density fermentations resulted in approximately 2.7 g of rPA per kg of cell paste (approximately 270 mg/L) of highly pure, biologically active rPA protein. The results presented here exhibit the ability to generate multi-gram quantities of rPA from E. coli that may be used for the development of new anthrax vaccines and anthrax therapeutics.     

A systematic review of adaptive wildlife management for the control of invasive,non-native mammals,and other human–wildlife conflicts

1. We are entering an era where species declines are occurring at their fastest ever rate, and the increased spread of non-native species is among the top causes. High uncertainty in biological processes makes the accurate prediction of the outcomes of management interventions very challenging. Adaptive management (AM) offers solutions to reduce uncertainty and improve predictability so that the outcomes of interventions can continuously improve.
2. We quantitatively assess the extent to which AM is used for managing vertebrates, with a focus on invasive non-native species (INNS). Using the Web of Science, we evaluated 3992 articles returned by the search terms ‘adaptive management’ or ‘adaptive harvest management’ against seven recommended elements of AM (engagement with stakeholders, defining objectives, forecasting and estimating uncertainty, implementing management, monitoring populations, adjusting management in response to monitoring, and improving forecasting and reducing uncertainty in response to monitoring populations).
3. The use of AM for vertebrates was reported in 56 (1%) of the evaluated studies; including four for managing INNS. Of these, ten studies excluding INNS and no studies of INNS management implemented all seven recommended elements of AM. Those elements infrequently implemented were as follows: the use of analysis or models to forecast and represent uncertainty (44%) and the feedback of monitoring data to improve forecasting and reduce uncertainty (25%).
4. Complete active AM has rarely been implemented and reported for managing INNS, despite the significant advantages it offers. Among studies purporting to have implemented AM, most did not use analyses or models to forecast and represent uncertainty, while most defined objectives, implemented management, and monitored populations.
5. Improvements to ongoing control programmes and much broader adoption of the AM approach are required to increase the efficiency and success of INNS management campaigns and reduce their negative impacts on native species.

     

Precopulatory choice for cues of material benefits in tree crickets

The relative importance of direct and indirect benefits modelsof mate choice is a central question in sexual selection, butseparating the two models is very difficult because high qualitymales often provide both better direct benefits and better genes.In tree crickets, Oecanthus nigricornis, females have the opportunityto gain both directly and indirectly from mate choice. Femaletree crickets exercise premating choice for large males, butthe model underlying this choice is unknown. In this study weexamine the proximate cues used by female tree crickets to rejectmales, and show that the ability of males to provide food isa central cue. In contrast, we find no evidence that the relativesize of mates is important in mate rejection. The fact thatthe major phenotypic cues of male quality are related to foodprovisioning suggests that the role of genetic benefits in shapingfemale preferences is limited by the extent to which food provisioningsignals genetic quality.