Spatial segregation of specialists and generalists in bird communities

Each species generally has a close relationship with one or more habitats and can therefore be classified as either specialist or generalist. We studied whether specialist and generalist species are spatially distributed independently of each other. Repeating the analysis for 100 of the most frequent terrestrial bird species recorded over the 10 000 sampled sites of the French Breeding Bird survey, we found that specialists were more abundant if the rest of the community was specialized, and that the inverse was also true. This pattern was far subtler than just a simple dichotomy: most species actually presented a maximum abundance at a value of community specialization similar to their own level of specialization. Bird communities appear very well defined along a specialist–generalist gradient. We believe this pattern becomes more apparent with habitat degradation. The consequences on both ecological services and community resilience may well be considerable.     

Exome sequences and multi‐environment field trials elucidate the genetic basis of adaptation in barley

Broadening the genetic base of crops is crucial for developing varieties to respond to global agricultural challenges such as climate change. Here, we analysed a diverse panel of 371 domesticated lines of the model crop barley to explore the genetics of crop adaptation. We first collected exome sequence data and phenotypes of key life history traits from contrasting multi‐environment common garden trials. Then we applied refined statistical methods, including some based on exomic haplotype states, for genotype‐by‐environment (G×E) modelling. Sub‐populations defined from exomic profiles were coincident with barley's biology, geography and history, and explained a high proportion of trial phenotypic variance. Clear G×E interactions indicated adaptation profiles that varied for landraces and cultivars. Exploration of circadian clock‐related genes, associated with the environmentally adaptive days to heading trait (crucial for the crop's spread from the Fertile Crescent), illustrated complexities in G×E effect directions, and the importance of latitudinally based genic context in the expression of large‐effect alleles. Our analysis supports a gene‐level scientific understanding of crop adaption and leads to practical opportunities for crop improvement, allowing the prioritisation of genomic regions and particular sets of lines for breeding efforts seeking to cope with climate change and other stresses.     

Proteomic analyses of intermediate filaments reveals cytokeratin8 is highly acetylated--implications for colorectal epithelial homeostasis.

Butyrate is a critical cancer-preventive element in the colon milieu whose mechanism of action is unclear, but appears to be mediated through inhibition of histone deacetylases (HDACs) and consequent alterations in global protein acetylation. Cytokeratins (CKs) have roles in cytoskeletal function as components of the intermediate filaments (IFs) and this involves CKs in the regulation of tissue homeostasis of high-turnover epithelia such as the colon. We used a 2-D gel/MS analysis to characterise the proteome of IFs, and a novel monitoring-initiated detection and sequencing (MIDAS) approach to identify acetylation sites on principal proteins. We report that CKs are highly acetylated in a colon cancer cell line, with five acetylation sites characterised on CK8 and a further one on CK18. Acetylation of CK8 is responsive to butyrate. HDAC5 is the deacetylase associated with IFs. These data indicate a novel action of butyrate as a cancer preventive agent. Acetylation of CK8 may be associated with IFs stabilisation and thereby provide a candidate mechanism for the appropriate retention or loss of epithelial cells from the flat mucosa.     

Radiolabeling rhesus monkey CD34+ hematopoietic and mesenchymal stem cells with 64Cu-pyruvaldehyde-bis(N4-methylthiosemicarbazone) for microPET imaging

Noninvasive positron emission tomography (PET) provides a potential method for in vivo tracking of radiolabeled cells. The goal of this study was to assess the potential toxicity of 64Cu-pyruvaldehyde-bis(N4-methylthiosemicarbazone) (PTSM) on rhesus monkey CD34+ hematopoietic and mesenchymal stem cells in vitro in preparation for developing imaging protocols posttransplantation. CD34+ hematopoietic cells were radiolabeled with 0 to 40 microCi/mL 64Cu-PTSM and viability and colony formation were assessed. Rhesus monkey mesenchymal stem cells (rhMSCs) were placed in culture postradiolabeling for assessments of growth and differentiation toward adipogenic, osteogenic, and chondrogenic lineages. The results indicated that CD34+ cells radiolabeled with 20 microCi/mL and rhMSCs radiolabeled with 10 microCi/mL 64Cu-PTSM did not result in adverse effects on growth or differentiation. Nonradioactive copper was also evaluated and showed that the presence of copper was not harmful to the cells. CD34+ cells and rhMSCs radiolabeled with the optimized concentrations of 20 and 10 microCi/mL, respectively, were also assessed using the microPET scanner. Studies showed that a minimum of 2.50x10(4) CD34+ cells (1.1 pCi/cell) and 6.25x10(3) rhMSCs (4.4 pCi/cell) could be detected. These studies indicate that CD34+ hematopoietic cells and rhMSCs can be safely radiolabeled with 64Cu-PTSM without adverse cellular effects.     

Spread and persistence of a rugulosin-producing endophyte in Picea glauca seedlings

We have studied Picea glauca (white spruce) endophyte colonization and its affect on the growth of Choristoneura fumiferana (spruce budworm). Here we examine the spread and persistence of a rugulosin-producing endophyte and rugulosin in needles from trees maintained in the nursery, as well as in trees planted in a test field site. Additionally, we report toxicity of rugulosin against three P. glauca needle herbivores: C. fumiferana, Lambdina fiscellaria (hemlock looper) and Zeiraphera canadensis (spruce budmoth). Reduction in body weight for both the C. fumiferana and L. fiscellaria were observed at 25 and 50 μm, respectively, and head capsules were reduced at 100 and 150 μm. Z. canadensis larvae did not perform as well in tests due to an Aspergillus fumigatus infection, but were shown to be lighter when tested with 100 and 150 μm compared with controls. The endophyte and its toxin were shown to spread throughout the nursery-grown seedlings. After 3.5 and 4.5 y post-inoculation (one and two years in the test site), the inoculated endophyte and its toxin had remained present with an average rugulosin concentration of 1 μg g⁻¹.     

Semiquantitative Performance and Mechanism Evaluation of Carbon Nanomaterials as Cathode Coatings for Microbial Fouling Reduction

In this study, we examine bacterial attachment and survival on a titanium (Ti) cathode coated with various carbon nanomaterials (CNM): pristine carbon nanotubes (CNT), oxidized carbon nanotubes (O-CNT), oxidized-annealed carbon nanotubes (OA-CNT), carbon black (CB), and reduced graphene oxide (rGO). The carbon nanomaterials were dispersed in an isopropyl alcohol-Nafion solution and were then used to dip-coat a Ti substrate. Pseudomonas fluorescens was selected as the representative bacterium for environmental biofouling. Experiments in the absence of an electric potential indicate that increased nanoscale surface roughness and decreased hydrophobicity of the CNM coating decreased bacterial adhesion. The loss of bacterial viability on the noncharged CNM coatings ranged from 22% for CB to 67% for OA-CNT and was dependent on the CNM dimensions and surface chemistry. For electrochemical experiments, the total density and percentage of inactivation of the adherent bacteria were analyzed semiquantitatively as functions of electrode potential, current density, and hydrogen peroxide generation. Electrode potential and hydrogen peroxide generation were the dominant factors with regard to short-term (3-h) bacterial attachment and inactivation, respectively. Extended-time electrochemical experiments (12 h) indicated that in all cases, the density of total deposited bacteria increased almost linearly with time and that the rate of bacterial adhesion was decreased 8- to 10-fold when an electric potential was applied. In summary, this study provides a fundamental rationale for the selection of CNM as cathode coatings and electric potential to reduce microbial fouling.     

HPV Serology Testing Confirms High HPV Immunisation Coverage in England

Background

Reported human papillomavirus (HPV) vaccination coverage in England is high, particularly in girls offered routine immunisation at age 12 years. Serological surveillance can be used to validate reported coverage and explore variations within it and changes in serological markers over time.

Methods

Residual serum specimens collected from females aged 15–19 years in 2010–2011 were tested for anti-HPV16 and HPV18 IgG by ELISA. Based on these results, females were classified as follows: seronegative, probable natural infection, probable vaccine-induced seropositivity, or possible natural infection/possible vaccine-induced seropositivity. The proportion of females with vaccine-induced seropositivity was compared to the reported vaccination coverage.

Results

Of 2146 specimens tested, 1380 (64%) were seropositive for both types HPV16 and HPV18 and 159 (7.4%) positive for only one HPV type. The IgG concentrations were far higher for those positive for both HPV types than those positive for only one HPV type. 1320 (62%) females were considered to have probable vaccine-induced seropositivity. Among vaccine-induced seropositives, antibody concentrations declined with increasing age at vaccination and increasing time since vaccination.

Conclusions

The proportion of females with vaccine-induced seropositivity was closest to the reported 3-dose coverage in those offered the vaccination at younger ages, with a greater discrepancy in the older females. This suggests either some under-reporting of immunisations of older females and/or that partial vaccination (i.e. one- or two-doses) has provided high antibody responses in 13–17 year olds.     

A fluorescence-based assay for indoleamine 2,3-dioxygenase

A rapid and sensitive fluorescence-based bioassay for determination of indoleamine 2,3-dioxygenase (IDO) activity has been developed. This assay relies on the quantification of the amount of kynurenine produced in the assay medium by fluorescence and complements the standard absorbance and high-performance liquid chromatography (HPLC) assay methods. The fluorescence method has limits of detection similar to those of the standard assay methods. Measured activities of IDO, including in the presence of tryptophan-based inhibitors, were in statistical agreement with the absorbance and HPLC assay methods. The fluorescence-based assay was also suitable for assessment of IDO inhibition by compounds that are incompatible with the absorbance method.