Homogenous Population Genetic Structure of the Non-Native Raccoon Dog (Nyctereutes procyonoides) in Europe as a Result of Rapid Population Expansion

The extent of gene flow during the range expansion of non-native species influences the amount of genetic diversity retained in expanding populations. Here, we analyse the population genetic structure of the raccoon dog (Nyctereutes procyonoides) in north-eastern and central Europe. This invasive species is of management concern because it is highly susceptible to fox rabies and an important secondary host of the virus. We hypothesized that the large number of introduced animals and the species’ dispersal capabilities led to high population connectivity and maintenance of genetic diversity throughout the invaded range. We genotyped 332 tissue samples from seven European countries using 16 microsatellite loci. Different algorithms identified three genetic clusters corresponding to Finland, Denmark and a large ‘central’ population that reached from introduction areas in western Russia to northern Germany. Cluster assignments provided evidence of long-distance dispersal. The results of an Approximate Bayesian Computation analysis supported a scenario of equal effective population sizes among different pre-defined populations in the large central cluster. Our results are in line with strong gene flow and secondary admixture between neighbouring demes leading to reduced genetic structuring, probably a result of its fairly rapid population expansion after introduction. The results presented here are remarkable in the sense that we identified a homogenous genetic cluster inhabiting an area stretching over more than 1500km. They are also relevant for disease management, as in the event of a significant rabies outbreak, there is a great risk of a rapid virus spread among raccoon dog populations.     

Desiccation of microspore derived embryos of oilseed rape (Brassica napus L.)

Summary Microspore-derived embryos from Brassica napus L. were dried to less than 15% moisture and stored dry for a minimum of 7 days. Successful plant regeneration was observed when embryos at the cotyledonary stage of development were treated with 50 uM ABA for 7 days prior to desiccation. Solid agar or liquid medium gave similar results. The rate of drying of embryos after ABA pretreatment had only minor effects on embryo survival, but for untreated embryos, slow drying gave a small degree of survival. These results are very comparable to those with alfalfa somatic embryos, suggesting that the ABA treatment of cotyledonary stage embryos may be broadly used as a pretreatment for inducing the expression of desiccation tolerance in plant embryos.     

Selection by parasitoid females among closely related hosts based on volatiles: Identifying relevant chemical cues

Parasitoid fitness is influenced by the ability to overcome host defense strategies and by the ability of parasitoid females to select high‐quality host individuals. When females are unable to differentiate among hosts, their fitness will decrease with an increasing abundance of resistant hosts. To understand the effect of mixed host populations on female fitness, it is therefore necessary to investigate the ability of female parasitoids to select among hosts. Here, we used behavioral assays, headspace volatile collection, and electrophysiology to study the ability of Asecodes parviclava to use olfactory cues to select between a susceptible host (Galerucella calmariensis) and a resistant host (Galerucella pusilla) from a distance. Our studies show that parasitoid females have the capacity to distinguish the two hosts and that the selection behavior is acquired through experiences during earlier life stages. Further, we identified two volatiles (α‐terpinolene and [E]‐β‐ocimene) which amounts differ between the two plant–herbivore systems and that caused behavioral and electrophysiological responses. The consequence of this selection behavior is that females have the capacity to avoid laying eggs in G. pusilla, where the egg mortality is higher due to much stronger immune responses toward A. parviclava than in larvae of G. calmariensis.     

Can low concentrations of Papain help repair articular cartilage defects?

In the present study, we investigate the capability of low concentrations of Papain to stimulate cartilage mesenchymal cells proliferation and transformation to chondrocytes and evaluate the healing capability of partial thickness defects in medial condyle cartilage of 30 rabbits’ knee joints. Papain 0.1 mg/ml and Ringer saline l ml each were injected intra-articularly to rabbits of experimental and control groups (15 animals each). Healthy cartilage from lateral condyle and cartilage from medial condyle where the surgical defect was created were studied histologically and by TEM. The study revealed that 0.1 mg/ml Papain activates proliferation and spreading of mesenchymal stem cells to young forms of chondrocyte from perichondrium to the upper layers of healthy cartilage. In only 22.27% cases of the experimental group, surgical defects filled with cartilaginous tissue on the background of distinct destruction of collagenous matrix in the native cartilage. However, in 55.5% of the control group the defect was spontaneously healed by hyaline cartilaginous tissue completely or partially on the basis of slight destruction of collagenous matrix. The defect site was filled with activated chondrocyte-like cells from the subchondral plate (not perichondrium) in both groups, which acquired some cisterns of rough endoplasmic reticulum (RER) and produced matrix proteins. The results suggest that Papain did not ameliorate the recovery of cartilage defects acquired through surgically-induced injury of collagenous matrix in native cartilage. We observed that articular cartilage is the source of mesenchymal stem cells which have the ability to transform into young forms of chondrocytes. This transformation process depends on the level of destruction of native cartilage collagen matrix induced by the defect or by Papain.     

A Preference Based Measure of Complementary Feeding Quality: Application to the Avon Longitudinal Study of Parents and Children

This paper presents the development of the Complementary Feeding Utility Index (CFUI), a composite index aimed to measure adherence to infant feeding guidelines. Through an axiomatic characterization this paper shows the advantages in using the CFUI are the following: it avoids the use of arbitrary cut-offs, and by converting observed diet preferences into utilities, summing the score is meaningful. In addition, as the CFUI is designed to be scored continuously, it allows the transition from intake of beneficial foods (in low quantities) and intake of detrimental foods (in high quantities) to be more subtle. The paper first describes the rationale being the development of the CFUI and then elaborates on the methodology used to develop the CFUI, including the process of selecting the components. The methodology is applied to data collected from the Avon Longitudinal Study of Parents and Children to show the advantages of the CFUI over traditional diet index approaches. Unlike traditional approaches, the distribution of the CFUI does not peak towards mean value but distributes evenly towards the tails of the distribution.     

Migration and isolation during the turbulent Ponto‐Caspian Pleistocene create high diversity in the crustacean Paramysis lacustris

The Ponto‐Caspian brackish‐water fauna inhabits estuaries and rivers of the Black, Azov and Caspian seas and is fragmented by higher salinity waters and a major interbasin watershed. The fauna is known for the high levels of endemism, complex zoogeographic histories, and as a recent source of successful invasive species. It remains debated whether the Black and Azov Sea brackish‐water populations survived unfavourable Pleistocene conditions in multiple separate refugia or whether the two seas were (repeatedly) recolonized from the Caspian. Using microsatellite and mtDNA markers, we demonstrate deep among‐ and within‐basin subdivisions in a widespread Ponto‐Caspian mysid crustacean Paramysis lacustris. Five genetic clusters were identified, but their relationships did not reflect the geography of the region. The Azov cluster was the most distinct (4–5% COI divergence), despite its geographic position in the corridor between Black and Caspian seas, and may represent a new species. In the northern Black Sea area, the Dnieper cluster was closer to the Caspian cluster than to the neighbouring Danube–Dniester–Bug populations, suggesting separate colonizations of the Black Sea. Overall, the data implied a predominant gene flow from the east to the Black Sea and highlight the importance of Caspian Sea transgressions in facilitating dispersal. Yet, the presence of distinct lineages in the Black Sea points to the persistence of isolated refugial populations that have gained diagnostic differences under presumably high mutation rates and large population sizes. The unfavourable Pleistocene periods in the Black Sea therefore appear to have promoted diversification of the brackish‐water lineages, rather than extirpated them.     

Do Dietary Trajectories between Infancy and Toddlerhood Influence IQ in Childhood and Adolescence? Results from a Prospective Birth Cohort Study

Objective

We examined whether trajectories of dietary patterns from 6 to 24 months of age are associated with intelligence quotient (IQ) in childhood and adolescence.

Methods

Participants were children enrolled in a prospective UK birth cohort (n = 7652) who had IQ measured at age 8 and/or 15 years. Dietary patterns were previously extracted from questionnaires when children were aged 6, 15 and 24 months using principal component analysis. Dietary trajectories were generated by combining scores on similar dietary patterns across each age, using multilevel mixed models. Associations between dietary trajectories and IQ were examined in generalized linear models with adjustment for potential confounders.

Results

Four dietary pattern trajectories were constructed from 6 to 24 months of age and were named according to foods that made the strongest contribution to trajectory scores; Healthy (characterised by breastfeeding at 6 months, raw fruit and vegetables, cheese and herbs at 15 and 24 months); Discretionary (biscuits, chocolate, crisps at all ages), Traditional (meat, cooked vegetables and puddings at all ages) and, Ready-to-eat (use of ready-prepared baby foods at 6 and 15 months, biscuits, bread and breakfast cereals at 24 months). In fully-adjusted models, a 1 SD change in the Healthy trajectory was weakly associated with higher IQ at age 8 (1.07 (95%CI 0.17, 1.97)) but not 15 years (0.49 (−0.28, 1.26)). Associations between the Discretionary and Traditional trajectories with IQ at 8 and 15 years were as follows; Discretionary; 8 years −0.35(−1.03, 0.33), 15 years −0.73(−1.33, −0.14) Traditional; 8 years −0.19(−0.71, 0.33)15 years −0.41(−0.77, −0.04)). The Ready-to-eat trajectory had no association with IQ at either age (8 years 0.32(−4.31, 4.95), 15 years 1.11(−3.10, 5.33).

Conclusions

The Discretionary and Traditional dietary pattern trajectories from 6 to 24 months of age, over the period when food patterns begin to emerge, are weakly associated with IQ in adolescence.     

Altered conductance and permeability of Cx40 mutations associated with atrial fibrillation

Gap junctions ensure the rapid propagation of the action potential throughout the myocardium. Three mutant forms of connexin40 (Cx40; A96S, M163V, and G38D), the primary component of the atrial gap junction channel, are associated with atrial fibrillation and retain the ability to form functional channels. We determined the biophysical properties of these mutant gap junctions in transiently transfected HeLa and N2A cells. All three mutants showed macroscopic junctional conductances over the range of 0.5 to 40 nS, and voltage dependences comparable to those of wild-type (WT) Cx40. However, the unitary conductance of G38D channels was ∼1.6-fold higher than that of WT Cx40 channels (∼220 vs. ∼135 pS), whereas the unitary conductances of the A96S and M163V mutants were similar to that of WT Cx40. Furthermore, the M163V and G38D channels exhibited approximately two- and approximately fivefold higher permeability to the anionic dye Lucifer yellow (LY) relative to K⁺ (LY/K⁺) compared with that of WT Cx40, whereas A96S LY transfer was similar to that of WT (G38D > M163V > A96S ≈ Cx40WT). In contrast, G38D channels were almost impermeable to cationic ethidium bromide (EtBr), suggesting that G38D alters channel selectivity. Conversely, A96S and M163V channels showed enhanced EtBr permeability relative to WT Cx40, with the following permeability order: M163V > A96S > Cx40WT > G38D. Altered conductive and permeability properties of mutant channels suggest an essential role for Cx40-mediated biochemical and electrical coupling in cardiac tissues. The altered properties of the three single-base substitution mutants may play a role in mechanisms of reentry arrhythmias.