Molecular Phylogeny of theCeratosolenSpecies PollinatingFicusof the SubgenusSycomorus sensu stricto:Biogeographical History and Origins of the Species-Specificity Breakdown Cases

The 14 species ofFicusof the subgenusSycomorus(Moraceae) are invariably pollinated byCeratosolenspecies (Hym. Chalcidoidea), which in turn reproduce in the fig florets. They are distributed mostly in continental Africa, Madagascar, and the Mascarene and Comoro Islands, but 1 species extends its geographical range all over the Oriental region. Fig–pollinator relationships are usually strictly species specific, but exceptions to the ‘one-to-one’ rule occur within the group we studied. In order to understand both the biogeographical history of theCeratosolenspecies associated withFicusof the subgenusSycomorusand the origins of the specificity breakdown cases, we have used cytochromebsequences to reconstruct a phylogeny of the fig wasps. The results show that the pollinators from the Malagasy region and those from continental Africa form two distinct clades, which probably diverged after the crossing of the Mozambique Channel by an ancestral population. The Oriental wasp species show strong affinities with the African species. The two species-specificity exceptions are due to different evolutionary events. The occurrence of the two West African pollinators associated withF. surcan be explained by successive speciation events of the mutualistic partner without plant radiation. In contrast, we hypothesize thatC. galilishifted by horizontal transfer from an unknown, presumably extinct,Ficusspecies toF. sycomorusafter this native Malagasy fig species colonized Africa.     

Secretion of active β-lactamase to the medium mediated by the Escherichia coli haemolysin transport pathway

An in frame gene fusion containing the coding region for mature β-lactamase and the 3′-end of hylA encoding the haemolysin secretion signal, was constructed under the control of a lac promoter. The resulting 53 kDa hybrid protein was specifically secreted to the external medium in the presence of the haemolysin translocator proteins, HlyB and HlyD. The specific activity of the β-lactamase portion of the secreted protein (measured by the hydrolysis of penicillin G), approximately 1 U/μg protein, was close to that of authentic, purified TEM-β-lactamase. This is an important example of a hybrid protein that is enzymatically active, and secreted via the haemolysin pathway. Previous studies have indicated that haemolysin is secreted directly into the medium, bypassing the periplasm, to which β-lactamase is normally targeted. This study indicated, therefore, that normal folding of an active β-lactamase, can occur, at least when fused to the HlyA C-terminus, without the necessity of entering the periplasm. Despite the secretion of approximately 5 μg/ml levels of the active β-lactamase fusion into the medium, there was maximally only a 50% detectable increase in the LD₅₀ for resistance to ampicillin at the individual cell level. This result suggests that, normally, resistance to ampicillin requires a high concentration of the enzyme close to killing targets, i.e. in the periplasm, in order to achieve significant levels of protection.     

Landfills determine the distribution of an expanding breeding population of the endangered Egyptian Vulture Neophron percnopterus

Human activities provide food resources for animals that are predictable in space and/or time. These resources, sometimes referred to as predictable anthropogenic food subsidies (PAFS), can be either the result of human‐generated waste or provided intentionally, sometimes as a conservation measure. Some PAFS, including landfills, are used by common species. However, little information exists about the effects that these feeding points have on rarer species that feed there, some of which are of conservation concern. This study focuses on the influence of PAFS and their spatial location on the distribution of territories of the endangered Egyptian Vulture Neophron percnopterus. We analysed a population in the NE Iberian Peninsula that has in recent decades expanded its range. We used both null model and linear model analyses to ascertain the effect of PAFS and other covariates on the occupancy of territories by the study species. PAFS appeared to play an important role in territory selection by Egyptian Vultures, as occupied territories were nearer landfills than expected by chance. Furthermore, the distance from PAFS (landfills and vulture feeding stations, or ‘restaurants’) played an important role in the probability of territory occupancy by Egyptian Vultures, in addition to other environmental variables such as surface areas of rocky south‐facing slopes, human settlement and the proximity of conspecifics. However, recent EU legislation aims to phase out open‐air landfills to reduce the negative environmental effects of these facilities. This could have an undesired impact on the endangered species that use these feeding points. We recommend management measures that can control abundant pest species but, in the long term, other measures as supplementary feeding should be considered to counteract the probable negative effect of the disappearance of landfills on endangered species.     

Fatigue In Teenagers on the interNET - The FITNET Trial. A randomized clinical trial of web-based cognitive behavioural therapy for adolescents with chronic fatigue syndrome: study protocol. [ISRCTN59878666]

Background  

Chronic Fatigue Syndrome (CFS) is increasingly recognized as a cause of disability and inactivity in adolescents in the Netherlands. CFS is characterized by unexplained fatigue lasting more than 6 months. Cognitive Behavioural Therapy (CBT) has proven to be effective. However, CBT availability for adolescents with CFS is limited and requires special therapeutic skills not always readily available. An alternative to the face-to-face CBT is FITNET, a web-based therapeutic program designed specifically for adolescents diagnosed with CFS, and their parents. This new CBT approach appeals to the modern youth, who grow up with internet as their main source of information. A web-based program offers the opportunity to lower thresholds for the acceptance and realization of healthcare. This treatment can be activated at any chosen time. The communication between patient and therapist can elapse asynchronously. If effective, this web-based program would greatly increase the therapeutic accessibility.     

Transport genes and chemotaxis in Laribacter hongkongensis: a genome-wide analysis

Background

Laribacter hongkongensis is a Gram-negative, sea gull-shaped rod associated with community-acquired gastroenteritis. The bacterium has been found in diverse freshwater environments including fish, frogs and drinking water reservoirs. Using the complete genome sequence data of L. hongkongensis, we performed a comprehensive analysis of putative transport-related genes and genes related to chemotaxis, motility and quorum sensing, which may help the bacterium adapt to the changing environments and combat harmful substances.

Results

A genome-wide analysis using Transport Classification Database TCDB, similarity and keyword searches revealed the presence of a large diversity of transporters (n = 457) and genes related to chemotaxis (n = 52) and flagellar biosynthesis (n = 40) in the L. hongkongensis genome. The transporters included those from all seven major transporter categories, which may allow the uptake of essential nutrients or ions, and extrusion of metabolic end products and hazardous substances. L. hongkongensis is unique among closely related members of Neisseriaceae family in possessing higher number of proteins related to transport of ammonium, urea and dicarboxylate, which may reflect the importance of nitrogen and dicarboxylate metabolism in this assacharolytic bacterium. Structural modeling of two C⁴-dicarboxylate transporters showed that they possessed similar structures to the determined structures of other DctP-TRAP transporters, with one having an unusual disulfide bond. Diverse mechanisms for iron transport, including hemin transporters for iron acquisition from host proteins, were also identified. In addition to the chemotaxis and flagella-related genes, the L. hongkongensis genome also contained two copies of qseB/qseC homologues of the AI-3 quorum sensing system.

Conclusions

The large number of diverse transporters and genes involved in chemotaxis, motility and quorum sensing suggested that the bacterium may utilize a complex system to adapt to different environments. Structural modeling will provide useful insights on the transporters in L. hongkongensis.     

Local interleukin-10 production during respiratory syncytial virus bronchiolitis is associated with post-bronchiolitis wheeze

Background

Respiratory syncytial virus (RSV) is the most common cause of bronchiolitis in infants. Following RSV bronchiolitis, 50% of children develop post-bronchiolitis wheeze (PBW). Animal studies have suggested that interleukin (IL)-10 plays a critical role in the pathogenesis of RSV bronchiolitis and subsequent airway hyperresponsiveness. Previously, we showed that ex vivo monocyte IL-10 production is a predictor of PBW. Additionally, heterozygosity of the single-nucleotide polymorphism (SNP) rs1800872 in the IL10 promoter region was associated with protection against RSV bronchiolitis.

Methods

This study aimed to determine the in vivo role of IL-10 in RSV pathogenesis and recurrent wheeze in a new cohort of 235 infants hospitalized for RSV bronchiolitis. IL-10 levels in nasopharyngeal aspirates (NPAs) were measured at the time of hospitalization and the IL10 SNP rs1800872 genotype was determined. Follow-up data were available for 185 children (79%).

Results

Local IL-10 levels during RSV infection turned out to be higher in infants that later developed physician diagnosed PBW as compared to infants without PBW in the first year after RSV infection (958 vs 692 pg/ml, p = 0.02). The IL10 promoter SNP rs1800872 was not associated with IL-10 concentration in NPAs.

Conclusion

The relationship between high local IL-10 levels during the initial RSV infection and physician diagnosed PBW provides further evidence of the importance of the IL-10 response during RSV bronchiolitis.