Epidemiology and Genetic Characterization of Measles Strains in Senegal, 2004-2013

BackgroundIn Senegal, with the variable routine vaccination coverage, the risk for illness and death from measles still exists as evidenced by the measles epidemic episode in 2009. Since 2002 a laboratory-based surveillance system of measles was established by the Ministry of Health and the Institut Pasteur de Dakar. The present study analysed the data collected over the 10 years inclusive between 2004-2013 in order to define a measles epidemiological profile in Senegal, and we carried out a phylogenetic analysis of measles virus circulating in Senegal over the period 2009-2012.ConclusionImprovements in the measles surveillance in Senegal are required and the introduction of oral fluid and FTA cards as an alternative to transportation of sera should be investigated to improve surveillance. The introduction of a national vaccine database including number of doses of measles-containing vaccine will greatly improve efforts to interrupt and ultimately eliminate measles virus transmission in Senegal.     

Inter-individual relationships in empathic traits and feedback-related fronto-central brain activity: an event-related potential study

Background

Neuroimaging studies continue to indicate the major role the anterior cingulate cortex (ACC) plays in processing empathic responses. Error-related negativity (ERN), an event-related potential (ERP) thought to arise from the ACC, has been found to correlate with scores for individual empathic personality. This study investigated the relationship between empathic personality traits and the amplitude of feedback-related negativity (FRN), an ERP sourced from the ACC and similar to the ERN, using a task involving feedback of monetary gains or losses.

Methods

Sixteen healthy participants answered an empathy trait questionnaire and performed a gambling task to elicit FRN. Because FRN amplitude is thought to be associated with attention, motivation, emotional state, and anxiety trait, we performed a partial correlation analysis between the empathic trait score and FRN amplitude while controlling for variables.

Results

In partial correlation analysis, FRN amplitude was significantly inversely correlated with scores for personal distress and marginally correlated with scores for empathic concern and with total average score.

Discussion

The study revealed for the first time an association between FRN and emotional empathic traits, after controlling for variables that can affect FRN amplitude. However, we also found a reversed directional correlation contrary to our expectations. This fronto-central brain activity may be associated with empathic properties via dopaminergic neuronal function. Future study using these electric potentials as experimental tools is expected to help elucidate the neurological mechanism of empathy.

     

Clinical,Virological and Immunological Features from Patients Infected with Re-Emergent Avian-Origin Human H7N9 Influenza Disease of Varying Severity in Guangdong Province

BackgroundThe second wave of avian influenza H7N9 virus outbreak in humans spread to the Guangdong province of China by August of 2013 and this virus is now endemic in poultry in this region.MethodsFive patients with H7N9 virus infection admitted to our hospital during August 2013 to February 2014 were intensively investigated. Viral load in the respiratory tract was determined by quantitative polymerase chain reaction (Q-PCR) and cytokine levels were measured by bead-based flow cytometery.ResultsFour patients survived and one died. Viral load in different clinical specimens was correlated with cytokine levels in plasma and broncho-alveolar fluid (BALF), therapeutic modalities used and clinical outcome. Intravenous zanamivir appeared to be better than peramivir as salvage therapy in patients who failed to respond to oseltamivir. Higher and more prolonged viral load was found in the sputum or endotracheal aspirates compared to throat swabs. Upregulation of proinflammatory cytokines IP-10, MCP-1, MIG, MIP-1α/β, IL-1β and IL-8 was found in the plasma and BALF samples. The levels of cytokines in the plasma and viral load were correlated with disease severity. Reactivation of herpes simplex virus type 1(HSV-1) was found in three out of five patients (60%).ConclusionExpectorated sputum or endotracheal aspirate specimens are preferable to throat swabs for detecting and monitoring H7N9 virus. Severity of the disease was correlated to the viral load in the respiratory tract as well as the extents of cytokinemia. Reactivation of HSV-1 may contribute to clinical outcome.     

Parent–offspring resemblance in colony-specific adult survival of cliff swallows

Survival is a key component of fitness. Species that occupy discrete breeding colonies with different characteristics are often exposed to varying costs and benefits associated with group size or environmental conditions, and survival is an integrative net measure of these effects. We investigated the extent to which survival probability of adult (≥1-year old) cliff swallows (Petrochelidon pyrrhonota) occupying different colonies resembled that of their parental cohort and thus whether the natal colony had long-term effects on individuals. Individuals were cross-fostered between colonies soon after hatching and their presence as breeders monitored at colonies in the western Nebraska study area for the subsequent decade. Colony-specific adult survival probabilities of offspring born and reared in the same colony, and those cross-fostered away from their natal colony soon after birth, were positively and significantly related to subsequent adult survival of the parental cohort from the natal colony. This result held when controlling for the effect of natal colony size and the age composition of the parental cohort. In contrast, colony-specific adult survival of offspring cross-fostered to a site was unrelated to that of their foster parent cohort or to the cohort of non-fostered offspring with whom they were reared. Adult survival at a colony varied inversely with fecundity, as measured by mean brood size, providing evidence for a survival–fecundity trade-off in this species. The results suggest some heritable variation in adult survival, likely maintained by negative correlations between fitness components. The study provides additional evidence that colonies represent non-random collections of individuals.     

Model toxin level does not directly influence the evolution of mimicry in the salamander <Emphasis Type="Italic">Plethodon cinereus</Emphasis>

The resemblance between palatable mimics and unpalatable models in Batesian mimicry systems is tempered by many factors, including the toxicity of the model species. Model toxicity is thought to influence both the occurrence of mimicry and the evolution of mimetic phenotypes, such that mimicry is most likely to persist when models are particularly toxic. Additionally, model toxicity may influence the evolution of mimetic phenotype by allowing inaccurate mimicry to evolve through a mechanism termed ‘relaxed selection’. We tested these hypotheses in a salamander mimicry system between the model Notophthalmus viridescens and the mimic Plethodon cinereus, in which N. viridescens toxicity takes the form of tetrodotoxin. Surprisingly, though we discovered geographic variation in model toxin level, we found no support for the hypotheses that model toxicity directly influences either the occurrence of mimicry or the evolution of mimic phenotype. Instead, a link between N. viridescens size and toxicity may indirectly lead to relaxed selection in this mimicry system. Additionally, limitations of predator perception or variation in the rate of phenotypic evolution of models and mimics may account for the evolution of imperfect mimicry in this salamander species. Finally, variation in predator communities among localities or modern changes in environmental conditions may contribute to the patchy occurrence of mimicry in P. cinereus.     

The temperature–size rule in a rotifer is determined by the mother and at the egg stage

In most ectotherms, compared with development at low temperatures, development at high temperatures results in the acceleration of maturation, which in turn results in a smaller size (temperature–size rule, TSR). It is not known at which developmental stages this thermal response is determined. We exposed different life stages of the rotifer Lecane inermis to 15, 20, or 25 °C to determine whether the TSR in the F1 generation is governed by the thermal conditions experienced by the mothers (F0 generation) during their development, during egg production, or during the development of the eggs or hatchlings. We found that the adult size was affected by the thermal conditions experienced by the mothers and embryos, but not by the conditions during post-hatching growth. We suggest that the thermal plasticity producing the TSR in rotifers may reflect the joint impacts of a maternal effect and a direct effect of the environment during egg development. The two-point control of the TSR resembles the thermal determination of other biological phenomena, similar to the thermally determined sex determination in ectotherms. Our results contribute not only to better understanding the proximate mechanisms of TSR, but also to comprehending the general biological mechanisms of response to temperature, which is one of the most important ecological factors.     

Characterization of surface motility in <Emphasis Type="Italic">Sinorhizobium meliloti</Emphasis>: regulation and role in symbiosis

Sinorhizobium meliloti can exhibit diverse modes of surface translocation whose manifestation depends on the strain. The mechanisms involved and the role played by the different modes of surface motility in the establishment of symbiosis are largely unknown. In this work, we have characterized the surface motility shown by two S. meliloti reference strains (Rm1021 and GR4) under more permissive conditions for surface spreading and analyzed the symbiotic properties of two flagella-less S. meliloti mutants with different behavior on surfaces. The use of Noble agar in semisolid minimal medium induces surface motility in GR4, a strain described so far as non-motile on surfaces. The motility exhibited by GR4 is swarming as revealed by the non-motile phenotype of the flagella-less flaAB mutant. Intriguingly, a flgK mutation which also abolishes flagella production, triggers surface translocation in GR4 through an as yet unknown mechanism. In contrast to GR4, Rm1021 moves over surfaces using mostly a flagella-independent motility which is highly reliant on siderophore rhizobactin 1021 production. Surprisingly, this motility is absent in a flagella-less flgE mutant. In addition, we found that fadD loss-of-function, known to promote surface motility in S. meliloti, exerts different effects on the two reference strains: while fadD inactivation promotes a flagella-independent type of motility in GR4, the same mutation interferes with the surface translocation exhibited by the Rm1021 flaAB mutant. The symbiotic phenotypes shown by GR4flaAB and GR4flgK, non-flagellated mutants with opposite surface motility behavior, demonstrate that flagella-dependent motility positively influences competitiveness for nodule occupation, but is not crucial for optimal infectivity.     

The high diversity of <Emphasis Type="Italic">Lotus corniculatus</Emphasis> endosymbionts in soils of northwest Spain

The diversity of rhizobia that establish symbiosis with Lotus corniculatus has scarcely been studied. Several species of Mesorhizobium are endosymbionts of this legume, including Mesorhizobium loti, the type species of this genus. We analysed the genetic diversity of strains nodulating Lotus corniculatus in Northwest Spain and ten different RAPD patterns were identified among 22 isolates. The phylogenetic analysis of the 16S rRNA gene showed that the isolated strains belong to four divergent phylogenetic groups within the genus Mesorhizobium. These phylogenetic groups are widely distributed worldwide and the strains nodulate L. corniculatus in several countries of Europe, America and Asia. Three of the groups include the currently described Mesorhizobium species M. loti, M. erdmanii and M. jarvisii which are L. corniculatus endosymbionts. An analysis of the recA and atpD genes showed that our strains belong to several clusters, one of them very closely related to M. jarvisii and the remanining ones phylogenetically divergent from all currently described Mesorhizobium species. Some of these clusters include L. corniculatus nodulating strains isolated in Europe, America and Asia, although the recA and atpD genes have been sequenced in only a few L. corniculatus endosymbionts. The results of this study revealed great phylogenetic diversity of strains nodulating L. corniculatus, allowing us to predict that even more diversity will be discovered as further ecosystems are investigated.     

<Emphasis Type="Italic">Paradevosia shaoguanensis</Emphasis> gen. nov., sp. nov., Isolated from a Coking Wastewater

A Gram staining negative, rod-shaped, aerobic bacterial strain J5-3^T with a single polar flagellum was isolated from coking wastewater collected from Shaoguan, Guangdong, China. It was motile and capable of optimal growth at pH 6–8, 30 °C, and 0–2 % (w/v) NaCl. Its predominant fatty acids were 11-methyl C_18:1 ω7c (29.2 %), C_16:0 (20.6 %), C_19:0 cyclo ω8c (18.2 %), C_18:0 (11.0 %), and C_18:1 ω7c/C_18:1 ω6c (10.9 %) when grown on trypticase soy agar. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, two unknown glycolipids (GL1, GL2), and two unknown phospholipid (PL1, PL2). The predominant ubiquinone was Q-10, and the genome DNA G+C content was 61.7 mol %. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that strain J5-3^T belonged to the family Hyphomicrobiaceae in Alphaproteobacteria. It shared the 16S rRNA gene sequence similarities of 93.8–96.1 % with the genus Devosia, 94.5–94.8 % with the genus Pelagibacterium, and <92.0 % with all the other type strains in family Hyphomicrobiaceae. It can be distinguished from the closest phylogenetic neighbors based on several phenotypic and genotypic features, including α-galactosidase activity, tetracycline susceptibility, major fatty acid composition, polar lipid profile, DNA gyrase B subunit (gyrB) gene sequence, and random-amplified polymorphic DNA profile. Therefore, we consider strain J5-3^T to represent a novel species of a novel genus within the family Hyphomicrobiaceae, for which the name Paradevosia shaoguanensis gen. nov., sp. nov. is proposed. The type strain of Paradevosia shaoguanensis is J5-3^T (=CGMCC 1.12430^T =LMG 27409^T).     

Nectaries and male-biased nectar production in protandrous flowers of a perennial umbellifer <Emphasis Type="Italic">Angelica sylvestris</Emphasis> L. (Apiaceae)

Nectar is the most common floral pollinator reward. In dichogamous species, floral nectar production rates can differ between sexual phases. We studied the structure of nectaries located on the stylopodium and nectar production in protandrous umbellifer Angelica sylvestris. Our study species produced nectar in both floral sexual phases. Nectar sugar concentration was low (on average 22 ± 11 %, mean ± SD) and the nectar hexose rich and composed of sucrose, glucose, fructose and a small amount of amino acids, including β-alanine, a non-protein amino acid. Although nectar composition and sugar concentration varied little between floral sexual phases, nectar production showed a threefold reduction during the stigma receptive period. This is in contrast to other studies of Apiaceae that have reported female-biased nectar production, but in the direction predicted by plant sexual selection theory, suggesting that in pollen-unlimited species, floral rewards mainly enhance male reproductive success. The structure of the nectary was similar at the two sexual stages investigated, and composed of a secretory epidermis and several layers of nectariferous and subsecretory parenchyma. The nectary cells were small, had large nuclei, numerous small vacuoles and dense, intensely staining cytoplasm with abundant endoplasmic reticulum, mitochondria and secretory vesicles. They contained abundant resin-like material that may potentially act as defence against microbes. Starch was rarely observed in the nectary cells, occurring predominantly at the female stage and mainly in guard and parenchyma cells in close proximity to stomata, and in subsecretory parenchyma. The main route of nectar release in A. sylvestris seems to be via modified stomata.