The invasive Leptoglossus seed bug,a threat for commercial seed crops,but for conifer diversity?

Among the recent introductions of alien insects in Europe, the polyphagous western conifer seed bug, Leptoglossus occidentalis Heidemann (Heteroptera; Coreidae) can seriously be regarded as a major threat for all the European conifer forests. In the current study combining laboratory and field experimentations, we characterized first bug damage by developing specific damage categories on seeds of different conifer species by the use of X-ray. Secondly, we investigated the impact of the invasive bug on key conifer species used for afforestation in Western and Central Europe. For this purpose, we performed germination tests on predated seeds which revealed that even light damage (consumption of <1/3 of the whole seed content) strongly reduced the germination capability of the seed. We also compared the impact of feeding on the proportion of filled seeds. Second year cones of Pinus sylvestris and Pinus nigra have been enclosed and offered to different life stages (nymphs and adults) and the results showed a significant reduction of filled seeds whatever the life stage. In field, we annually surveyed the bug seed damage for six different conifer species planted in southwestern French seed orchards. Taking into account the economic value of improved seeds in seed orchards, economic impact of bug damage was important although never exceeded 25 %. Two natural or semi-natural alpine pine stands were also surveyed and appeared to be highly affected by the bug (up to 70 % of damaged seeds). Therefore, bug damage could also be considered as a serious threat for seed production in natural stands.     

Trophic overlap between sexes in the dimorphic African black oystercatcher foraging on an alien mussel

Sex‐specific feeding segregation related to sexual bill dimorphism has been described in several oystercatcher species, including the African black oystercatcher. For the latter, studies concerned only a small number of breeding pairs and were done prior the invasion of the South African rocky shores by the Mediterranean mussel, which is believed to have benefited oystercatchers by increasing overall biomass. Here, we investigated geographic variability in the segregation of diet, biometrics and body condition between sexes in the African species, in relation to changes in foraging habitats along the South African coastline, using stable isotope analyses. Males and females and their potential prey (mussels, limpets, polychaetes and ascidians) were sampled on the southern African west, south‐west and south‐east coasts for stable isotope analyses and biometrics and body conditions of birds were measured. Bill dimorphism occurred throughout the study area and south‐west males had lower body conditions than other males and females in general. Sexes displayed little differences in their δ¹³C ratios and in the relative consumption of the different prey throughout the study area, except on the south‐east coast where males were slightly depleted in ¹³C relative to females and the most abundant prey elsewhere (the Mediterranean mussel) is rare. Females were slightly but significantly enriched in ¹⁵N by 0.3‰ compared to their breeding partners and this did not link clearly to differences in diet. We argue that the combined effect of biogeographic variations in rocky shores diversity and biomass, heterogeneous invasion by the Mediterranean mussel on the South African coastline and bill dimorphism may have altered the sex‐specific feeding behaviour of oystercatchers differently between coastal regions and possibly had an additional cost for male oystercatchers faced with lower prey biomass and diversity on the south‐west coast.     

Flagellin/TLR5 signalling activates renal collecting duct cells and facilitates invasion and cellular translocation of uropathogenic Escherichia coli

Uropathogenic Escherichia coli (UPEC) colonizing kidneys is the main cause of acute pyelonephritis. TLR5 that senses flagellin was shown to be highly expressed in the bladder and to participate in host defence against flagellated UPEC, although its role in kidneys still remains elusive. Here we show that TLR5 is expressed in renal medullary collecting duct (MCD) cells, which represent a preferential site of UPEC adhesion. Flagellin, like lipopolysaccharide, stimulated the production of the chemoattractant chemokines CXCL1 and CXCL2, and subsequent migration capacity of neutrophils in cultured wild‐type (WT) and Tlr4^?/? MCDs, but not in Tlr5^?/? MCDs. UPEC can translocate across intact MCD layers without altering tight junctions. Strikingly, the invasion capacity and transcellular translocation of the UPEC strain HT7 were significantly lower in Tlr5^?/? than in WT MCDs. The non‐motile HT7ΔfliC mutant lacking flagellin also exhibited much lower translocation capacities than the HT7 isolates. Finally, Tlr5^?/? kidneys exhibited less infiltrating neutrophils than WT kidneys one day after the transurethral inoculation of HT7, and greater delayed renal bacterial loads in the day 4 post‐infected Tlr5^?/? kidneys. Overall, these findings indicate that the epithelial TLR5 participates to renal antibacterial defence, but paradoxically favours the translocation of UPEC across intact MCD cell layers.     

Organization and evolution of transposable elements along the bread wheat chromosome 3B

Background

The 17 Gb bread wheat genome has massively expanded through the proliferation of transposable elements (TEs) and two recent rounds of polyploidization. The assembly of a 774 Mb reference sequence of wheat chromosome 3B provided us with the opportunity to explore the impact of TEs on the complex wheat genome structure and evolution at a resolution and scale not reached so far.

Results

We develop an automated workflow, CLARI-TE, for TE modeling in complex genomes. We delineate precisely 56,488 intact and 196,391 fragmented TEs along the 3B pseudomolecule, accounting for 85% of the sequence, and reconstruct 30,199 nested insertions. TEs have been mostly silent for the last one million years, and the 3B chromosome has been shaped by a succession of bursts that occurred between 1 to 3 million years ago. Accelerated TE elimination in the high-recombination distal regions is a driving force towards chromosome partitioning. CACTAs overrepresented in the high-recombination distal regions are significantly associated with recently duplicated genes. In addition, we identify 140 CACTA-mediated gene capture events with 17 genes potentially created by exon shuffling and show that 19 captured genes are transcribed and under selection pressure, suggesting the important role of CACTAs in the recent wheat adaptation.

Conclusion

Accurate TE modeling uncovers the dynamics of TEs in a highly complex and polyploid genome. It provides novel insights into chromosome partitioning and highlights the role of CACTA transposons in the high level of gene duplication in wheat.

Electronic supplementary material

The online version of this article (doi:10.1186/s13059-014-0546-4) contains supplementary material, which is available to authorized users.     

The Recognition of and Care Seeking Behaviour for Childhood Illness in Developing Countries: A Systematic Review

Background

Pneumonia, diarrhoea, and malaria are among the leading causes of death in children. These deaths are largely preventable if appropriate care is sought early. This review aimed to determine the percentage of caregivers in low- and middle-income countries (LMICs) with a child less than 5 years who were able to recognise illness in their child and subsequently sought care from different types of healthcare providers.

Methods and Findings

We conducted a systematic literature review of studies that reported recognition of, and/or care seeking for episodes of diarrhoea, pneumonia or malaria in LMICs. The review is registered with PROSPERO (registration number: CRD42011001654). Ninety-one studies met the inclusion criteria. Eighteen studies reported data on caregiver recognition of disease and seventy-seven studies on care seeking. The median sensitivity of recognition of diarrhoea, malaria and pneumonia was low (36.0%, 37.4%, and 45.8%, respectively). A median of 73.0% of caregivers sought care outside the home. Care seeking from community health workers (median: 5.4% for diarrhoea, 4.2% for pneumonia, and 1.3% for malaria) and the use of oral rehydration therapy (median: 34%) was low.

Conclusions

Given the importance of this topic to child survival programmes there are few published studies. Recognition of diarrhoea, malaria and pneumonia by caregivers is generally poor and represents a key factor to address in attempts to improve health care utilisation. In addition, considering that oral rehydration therapy has been widely recommended for over forty years, its use remains disappointingly low. Similarly, the reported levels of care seeking from community health workers in the included studies are low even though global action plans to address these illnesses promote community case management. Giving greater priority to research on care seeking could provide crucial evidence to inform child mortality programmes.     

The Impact of Social Deprivation on Paranoia,Hallucinations, Mania and Depression: The Role of Discrimination Social Support,Stress and Trust

The negative implications of living in a socially unequal society are now well documented. However, there is poor understanding of the pathways from specific environmental risk to symptoms. Here we examine the associations between social deprivation, depression, and psychotic symptoms using the 2007 Adult Psychiatric Morbidity Survey, a cross-sectional dataset including 7,353 individuals. In addition we looked at the mediating role of stress, discrimination, trust and lack of social support. We found that the participants'' neighbourhood index of multiple deprivation (IMD) significantly predicted psychosis and depression. On inspection of specific psychotic symptoms, IMD predicted paranoia, but not hallucinations or hypomania. Stress and trust partially mediated the relationship between IMD and paranoid ideation. Stress, trust and a lack of social support fully mediated the relationship between IMD and depression. Future research should focus on the role deprivation and social inequalities plays in specific manifestations of psychopathology and investigate mechanisms to explain those associations that occur. Targeting the mediating mechanisms through appropriate psychological intervention may go some way to dampen the negative consequences of living in an unjust society; ameliorating economic injustice may improve population mental health.     

Colonisation of a Phage Susceptible Campylobacter jejuni Population in Two Phage Positive Broiler Flocks

The pathogens Campylobacter jejuni and Campylobacter coli are commensals in the poultry intestine and campylobacteriosis is one of the most frequent foodborne diseases in developed and developing countries. Phages were identified to be effective in reducing intestinal Campylobacter load and this was evaluated, in the first field trials which were recently carried out. The aim of this study was to further investigate Campylobacter population dynamics during phage application on a commercial broiler farm. This study determines the superiority in colonisation of a Campylobacter type found in a field trial that was susceptible to phages in in vitro tests. The colonisation factors, i.e. motility and gamma glutamyl transferase activity, were increased in this type. The clustering in phylogenetic comparisons of MALDI-TOF spectra did not match the ST, biochemical phenotype and phage susceptibility. Occurrence of Campylobacter jejuni strains and phage susceptibility types with different colonisation potential seem to play a very important role in the success of phage therapy in commercial broiler houses. Thus, mechanisms of both, phage susceptibility and Campylobacter colonisation should be further investigated and considered when composing phage cocktails.