Mycoplasma pneumoniae CARDS Toxin Exacerbates Ovalbumin-Induced Asthma-Like Inflammation in BALB/c Mice

Mycoplasma pneumoniae causes a range of airway and extrapulmonary pathologies in humans. Clinically, M. pneumoniae is associated with acute exacerbations of human asthma and a worsening of experimentally induced asthma in mice. Recently, we demonstrated that Community Acquired Respiratory Distress Syndrome (CARDS) toxin, an ADP-ribosylating and vacuolating toxin synthesized by M. pneumoniae, is sufficient to induce an asthma-like disease in BALB/cJ mice. To test the potential of CARDS toxin to exacerbate preexisting asthma, we examined inflammatory responses to recombinant CARDS toxin in an ovalbumin (OVA) murine model of asthma. Differences in pulmonary inflammatory responses between treatment groups were analyzed by histology, cell differentials and changes in cytokine and chemokine concentrations. Additionally, assessments of airway hyperreactivity were evaluated through direct pulmonary function measurements. Analysis of histology revealed exaggerated cellular inflammation with a strong eosinophilic component in the CARDS toxin-treated group. Heightened T-helper type-2 inflammatory responses were evidenced by increased expression of IL-4, IL-13, CCL17 and CCL22 corresponding with increased airway hyperreactivity in the CARDS toxin-treated mice. These data demonstrate that CARDS toxin can be a causal factor in the worsening of experimental allergic asthma, highlighting the potential importance of CARDS toxin in the etiology and exacerbation of human asthma.     

The Colposcopic Atlas of Schistosomiasis in the Lower Female Genital Tract Based on Studies in Malawi,Zimbabwe, Madagascar and South Africa

Background

Schistosoma (S.) haematobium is a neglected tropical disease which may affect any part of the genital tract in women. Female genital schistosomiasis (FGS) may cause abnormal vaginal discharge, contact bleeding, genital tumours, ectopic pregnancies and increased susceptibility to HIV. Symptoms may mimic those typical of sexually transmitted infections (STIs) and women with genital schistosomiasis may be incorrectly diagnosed. An expert consensus meeting suggested that the following findings by visual inspection should serve as proxy indicators for the diagnosis of schistosomiasis of the lower genital tract in women from S. haematobium endemic areas: sandy patches appearing as (1) single or clustered grains or (2) sandy patches appearing as homogenous, yellow areas, or (3) rubbery papules. In this atlas we aim to provide an overview of the genital mucosal manifestations of schistosomiasis in women.

Methodology/Principal findings

Photocolposcopic images were captured from women, between 1994 and 2012 in four different study sites endemic for S. haematobium in Malawi, Zimbabwe, South Africa and Madagascar. Images and specimens were sampled from sexually active women between 15 and 49 years of age. Colposcopic images of other diseases are included for differential diagnostic purposes.

Significance

This is the first atlas to present the clinical manifestations of schistosomiasis in the lower female genital tract. It will be freely available for online use, downloadable as a presentation and for print. It could be used for training purposes, further research, and in clinical practice.     

Improved protoplast culture and stability of cytoplasmic traits in plants regenerated from leaf protoplasts of cauliflower (Brassica oteracea ssp.botrytis)

Nearly 1000 plants have been regenerated from leaf protoplasts of two cauliflower (Brassica oleracea ssp.botrytis) alloplasmic inbred lines. One line (7642A) carried the Ogura (R1) cms cytoplasm derived from radish; the other line (7642B) carried a normalBrassica cytoplasm and was the fertile maintainer for the cms line. The majority of regenerated plants displayed normal vegetative morphology; they formed normal cauliflower heads and retained the floral characteristics of seed-grown plants from which they were derived. We found no change in either male sterility or in the low temperature-induced chlorosis associated with the 7642A line. Mitochondrial DNA analysis by hybridization with five cloned mtDNA probes revealed no apparent alteration in 75 regenerated plants of both lines. These results indicate that cytoplasmic traits inBrassica oleracea are stable after one cycle of in vitro culture and regeneration.     

Naringin levels in citrus tissues : I. Comparison of different antibodies and tracers for the radioimmunossay of naringin

The preparation of a tritiated radiotracer that was used in the radioimmunoassay of naringin (naringenin-7-O-α-rhamnosyl- (1-2)-β-d-glucopyranoside) and which was synthesized by reduction of the carbonyl group of the flavanone is reported. The resulting assay has a detection limit of 0.5 picomole per 0.1 milliliter, is specific for the 7-neohesperidoside substitution on flavanones, and can measure naringin in crude extracts of plant tissues. This radioimmunoassay is compared with three other naringin immunoassays which use antibodies raised against two different haptens and different tracers labeled with ¹²⁵I or ³H. The applicability of the methods to the quantification of naringin and other flavanone neohesperidosides in citrus tissue is discussed.     

Cricket calling communities as an indicator of the invasive ant <Emphasis Type="Italic">Wasmannia auropunctata</Emphasis> in an insular biodiversity hotspot

Invasive species are a major concern for the maintenance of ecosystem services and biodiversity but are difficult to mitigate. Upstream solutions to prevent their impact, including their detection, are needed. Wasmannia auropunctata, an invasive ant living in vagile supercolonies, is especially hard to track and is a major threat for tropical ecosystems and local animal communities. As part of such tropical communities, crickets are sensitive to ecological conditions, easy to collect, detectable and identifiable through their species-specific calls. Here, we evaluated the use of an acoustic community of crickets as an indicator of the presence of W. auropunctata in New Caledonia. We evaluated the dominance of the crickets in the soundscape, describe the cricket community structure and diversity along a shrubland to forest gradient, characterize these cricket communities structure and diversity in the light of ongoing invasion by W. auropunctata, and identify cricket species’ indicators of the invasion. Acoustic recordings collected on 24 sites were described using human-listening and spectrographic visualization. The results demonstrated a clear dominance of the cricket group in the New Caledonian nocturnal soundscapes. Each habitat harbored a specific acoustic cricket community related to specific environmental attributes including vegetation height, daily variation of humidity and temperature. The presence of W. auropunctata was significantly associated with a lower cricket acoustic activity and species richness at night. Of the 19 species detected, four nocturnal species were identified as indicator of non-invaded forests and preforests. This work supports the use of acoustic as an alternative method to detect invasion.     

ClinMine: Optimizing the Management of Patients in Hospital

Context

A better understanding of “patient pathway” thanks to data analysis can lead to better treatments for patients. The ClinMine project, supported by the French National Research Agency (ANR), aims at proposing, from various case studies, algorithmic and statistical models able to handle this type of pathway data, focusing primarily on hospital data.

SYNTHESIS AND BINDING OF PHYCOERYTHRIN AND ITS ASSOCIATED LINKERS TO THE PHYCOBILISOME IN RHODELLA VIOLACEA (RHODOPHYTA): COMPARED EFFECTS OF HIGH LIGHT AND TRANSLATION INHIBITORS1

We studied the synthesis and binding of phycoerythrin and its associated linkers to the phycobilisome (PBS) in Rhodella violacea (Kornmann) Wehrmeyer and compared the effects of high light and translation inhibitors on these processes. Rhodella violacea has a simple hemidiscoidal PBS structure with a well-known composition. The number of PBSs per cell decreases when irradiance is increased, and at higher irradiances the rods are shortened with a specific loss of the terminal hexamer of phycoerythrin (PE) and its associated linker. To test whether or not the observed variations were due to a coordination between the expression of the chloroplast-encoded PE and the nuclear-encoded linkers, we inhibited the expression of the chloroplast genes by the translation inhibitor chloramphenicol. In the few PBSs synthesized, the linker associated to the terminal PE hexamer was missing while that associated with the intermediate PE hexamer was still present. The inhibition by cycloheximide of the translation of the nuclear-encoded linkers did not influence the synthesis of the chloroplast-encoded phycobiliproteins. The absence of linkers prevented the formation of PE hexamers and their binding to the PBSs. We therefore propose the existence of two levels of regulation for PE and associated linkers: the intermediate PE hexamer and associated linker are always present even though their amount is reduced when irradiance is increased. In contrast, the terminal hexamer of PE and its associated linker are no longer present under high light. Their absence can be due to a feedback control between the level of PE and the synthesis of the linker: when the level of PE is lowered below a given value by the action of light on the chloroplast, a signal coming from the chloroplast reaches the nucleus and the synthesis of the linker is repressed. There is no sign of nuclear regulation of the synthesis of PE, but the nuclear-encoded linkers have a structural role in the formation of PE hexamers.     

Pronounced species turnover,but no functional equivalence in leaf consumption of invasive amphipods in the river Rhine

A growing body of literature focuses on the adverse effects of biological invasions, e.g., on the decline of indigenous biodiversity, while studies on the consequences of invasions on components of ecosystem functioning are comparatively rare. Owing to their leaf shredding activity, amphipods play a fundamental role in determining energy flow dynamics in Central European freshwater ecosystems, but whether the dramatic change in species composition after the invasion of Ponto–Caspian taxa affects this process has not been addressed in a comprehensive study. In a laboratory experiment we determined consumption rates of three leaf types (Alnus glutinosa, Betula pendula, Quercus robur) from common riparian arboreal vegetation in the Rhine drainage—one of the most heavily invaded river systems worldwide—by the most common native (Gammarus fossarum, G. pulex, G. roeselii) and invasive amphipods (Dikerogammarus villosus, Echinogammarus ischnus). Leaf-shredding activity was significantly lower in invasive than in native amphipods across leaf types, and a subsequent analysis ruled out an effect of different metabolic rates as an explanation. Another experiment was motivated by the observation that native amphipods are nowadays restricted to smaller tributaries to the Rhine, while invasive taxa are dominant in the main channel. As leaf litter shredding may be more important in headwaters than in lower parts of streams, we sought for a signature of within-species variation in the feeding ecology of amphipods and thus compared two different populations of G. pulex, but found very similar leaf consumption rates in upstream and downstream populations, suggesting that food preferences in amphipods could be species-specific with little potential for microevolution or environmentally induced plasticity. In conclusion, the rapid replacement of native amphipod species in the Rhine drainage likely affects vital ecosystem services, with the potential to change the aquatic food web (e.g., through reduced shredding activity and hence, reduced resource availability for particle-feeding detritivores), unless other taxonomic groups compensate for those functional alterations.     

Old Lineage on an Old Island: Pixibinthus,a New Cricket Genus Endemic to New Caledonia Shed Light on Gryllid Diversification in a Hotspot of Biodiversity

Few studies have focused on the early colonization of New Caledonia by insects, after the re-emergence of the main island, 37 Myr ago. Here we investigate the mode and tempo of evolution of a new endemic cricket genus, Pixibinthus, recently discovered in southern New Caledonia. First we formally describe this new monotypic genus found exclusively in the open shrubby vegetation on metalliferous soils, named ‘maquis minier’, unique to New Caledonia. We then reconstruct a dated molecular phylogeny based on five mitochondrial and four nuclear loci in order to establish relationships of Pixibinthus within Eneopterinae crickets. Pixibinthus is recovered as thesister clade of the endemic genus Agnotecous, mostly rainforest-dwellers. Dating results show that the island colonization by their common ancestor occurred around 34.7 Myr, shortly after New Caledonia re-emergence. Pixibinthus and Agnotecous are then one of the oldest insect lineages documented so far for New Caledonia. This discovery highlights for the first time two clear-cut ecological specializations between sister clades, as Agnotecous is mainly found in rainforests with 19 species, whereas Pixibinthus is found in open habitats with a single documented species. The preference of Pixibinthus for open habitats and of Agnotecous for forest habitats nicely fits an acoustic specialization, either explained by differences in body size or in acoustic properties of their respective habitats. We hypothesize that landscape dynamics, linked to major past climatic events and recent change in fire regimes are possible causes for both present-day low diversity and rarity in genus Pixibinthus. The unique evolutionary history of this old New Caledonian lineage stresses the importance to increase our knowledge on the faunal biodiversity of ‘maquis minier’, in order to better understand the origin and past dynamics of New Caledonian biota.     

Climate and Soil Type Together Explain the Distribution of Microendemic Species in a Biodiversity Hotspot

The grasshopper genus Caledonula, endemic to New Caledonia, was studied to understand the evolution of species distributions in relation to climate and soil types. Based on a comprehensive sampling of 80 locations throughout the island, the genus was represented by five species, four of which are new to science, of which three are described here. All the species have limited distributions in New Caledonia. Bioclimatic niche modelling shows that all the species were found in association with a wet climate and reduced seasonality, explaining their restriction to the southern half of the island. The results suggest that the genus was ancestrally constrained by seasonality. A molecular phylogeny was reconstructed using two mitochondrial and two nuclear markers. The partially resolved tree showed monophyly of the species found on metalliferous soils, and molecular dating indicated a rather recent origin for the genus. Adaptation to metalliferous soils is suggested by both morphological changes and radiation on these soils. The genus Caledonula is therefore a good model to understand the origin of microendemism in the context of recent and mixed influences of climate and soil type.