Hawksbill turtle terra incognita: conservation genetics of?eastern Pacific rookeries

Prior to 2008 and the discovery of several important hawksbill turtle (Eretmochelys imbricata) nesting colonies in the EP (Eastern Pacific), the species was considered virtually absent from the region. Research since that time has yielded new insights into EP hawksbills, salient among them being the use of mangrove estuaries for nesting. These recent revelations have raised interest in the genetic characterization of hawksbills in the EP, studies of which have remained lacking to date. Between 2008 and 2014, we collected tissue samples from 269 nesting hawksbills at nine rookeries across the EP and used mitochondrial DNA sequences (766 bp) to generate the first genetic characterization of rookeries in the region. Our results inform genetic diversity, population differentiation, and phylogeography of the species. Hawksbills in the EP demonstrate low genetic diversity: We identified a total of only seven haplotypes across the region, including five new and two previously identified nesting haplotypes (pooled frequencies of 58.4% and 41.6%, respectively), the former only evident in Central American rookeries. Despite low genetic diversity, we found strong stock structure between the four principal rookeries, suggesting the existence of multiple populations and warranting their recognition as distinct management units. Furthermore, haplotypes EiIP106 and EiIP108 are unique to hawksbills that nest in mangrove estuaries, a behavior found only in hawksbills along Pacific Central America. The detected genetic differentiation supports the existence of a novel mangrove estuary “reproductive ecotype” that may warrant additional conservation attention. From a phylogeographic perspective, our research indicates hawksbills colonized the EP via the Indo‐Pacific, and do not represent relict populations isolated from the Atlantic by the rising of the Panama Isthmus. Low overall genetic diversity in the EP is likely the combined result of few rookeries, extremely small reproductive populations and evolutionarily recent colonization events. Additional research with larger sample sizes and variable markers will help further genetic understanding of hawksbill turtles in the EP.     

Associations of Whole Blood n-3 and n-6 Polyunsaturated Fatty Acids with Blood Pressure in Children and Adolescents – Results from the IDEFICS/I.Family Cohort

BackgroundPolyunsaturated n-3 and n-6 polyunsaturated fatty acids (PUFA) are precursors of biologically active metabolites that affect blood pressure (BP) regulation. This study investigated the association of n-3 and n-6 PUFA and BP in children and adolescents.MethodsIn a subsample of 1267 children aged 2–9 years at baseline of the European IDEFICS (Identification and prevention of dietary- and lifestyle-induced health effects in children and infants) cohort whole blood fatty acids were measured by a validated gas chromatographic method. Systolic and diastolic BP was measured at baseline and after two and six years. Mixed-effects models were used to assess the associations between fatty acids at baseline and BP z-scores over time adjusting for relevant covariables. Models were further estimated stratified by sex and weight status.ResultsThe baseline level of arachidonic acid was positively associated with subsequent systolic BP (β = 0.08, P = 0.002) and diastolic BP (β = 0.07, P<0.001). In thin/normal weight children, baseline alpha-linolenic (β = -1.13, P = 0.003) and eicosapentaenoic acid (β = -0.85, P = 0.003) levels were inversely related to baseline and also to subsequent systolic BP and alpha-linolenic acid to subsequent diastolic BP. In overweight/obese children, baseline eicosapentaenoic acid level was positively associated with baseline diastolic BP (β = 0.54, P = 0.005).ConclusionsLow blood arachidonic acid levels in the whole sample and high n-3 PUFA levels in thin/normal weight children are associated with lower and therefore healthier BP. The beneficial effects of high n-3 PUFA on BP were not observed in overweight/obese children, suggesting that they may have been overlaid by the unfavorable effects of excess weight.     

In Vitro Study of Taenia solium Postoncospheral Form

Background

The transitional period between the oncosphere and the cysticercus of Taenia solium is the postoncospheral (PO) form, which has not yet been completely characterized. The aim of this work was to standardize a method to obtain T. solium PO forms by in vitro cultivation. We studied the morphology of the PO form and compared the expression of antigenic proteins among the PO form, oncosphere, and cysticerci stages.

Methodology/Principal Findings

T. solium activated oncospheres were co-cultured with ten cell lines to obtain PO forms, which we studied at three stages of development–days 15, 30, and 60. A high percentage (32%) of PO forms was obtained using HCT-8 cells in comparison to the other cell lines. The morphology was observed by bright field, scanning, and transmission electron microscopy. Morphology of the PO form changed over time, with the six hooks commonly seen in the oncosphere stage disappearing in the PO forms, and vesicles and microtriches observed in the tegument. The PO forms grew as they aged, reaching a diameter of 2.5 mm at 60 days of culture. 15–30 day PO forms developed into mature cysticerci when inoculated into rats. Antigenic proteins expressed in the PO forms are also expressed by the oncosphere and cysticerci stages, with more cysticerci antigenic proteins expressed as the PO forms ages.

Conclusions/Significance

This is the first report of an in vitro production method of T. solium PO forms. The changes observed in protein expression may be useful in identifying new targets for vaccine development. In vitro culture of PO form will aid in understanding the host-parasite relationship, since the structural changes of the developing PO forms may reflect the parasite’s immunoprotective mechanisms. A wider application of this method could significantly reduce the use of animals, and thus the costs and time required for further experimental investigations.     

Design,synthesis, and characterization of new cyclic d,l-α-alternate amino acid peptides by capillary electrophoresis coupled to electrospray ionization mass spectrometry

The self-assembly of peptide nanotubes (PNTs) depends on the structure and chemistry of cyclic peptide (CP) monomers, having an impact on their properties, making the choice of their monomers and their characterization a great challenge. We synthesized for the first time a new set of eight original CP sequences of 8, 10, and 12 d,l-α-alternate amino acids with a controlled internal diameter from 7 to 13 Å. They present various properties (e.g., diameter, global surface charge, hydrophobicity) that can open the way to new applications. Their structure and purity were determined thanks to a capillary electrophoresis coupled to electrospray ionization mass spectrometry (CE–ESI–MS) methodology developed for the first time for this purpose. The CPs were successfully separated in a basic hydro-organic background electrolyte (BGE, pH 8.0, H₂O/EtOH 50:50, v/v) and analyzed in MS positive mode. The effect of CP structure on electrophoretic mobility was studied, and the mass spectra were deeply analyzed. This methodology allowed verifying their purity and the absence of linear peptide precursors as well as their stability when stored over several months. Therefore, we have developed a new CE–ESI–MS methodology for the structure and purity control of interesting potential precursors for PNTs that could be employed as nanoplatforms in diagnostics or as pseudo sieving tools for separative purposes.     

Morphological and sexual traits in Atlas and Iberian Pied Flycatchers Ficedula hypoleuca speculigera and F. h. iberiae: a comparison

Capsule: There are significant biometric differences between Pied Flycatchers from Iberian and north African populations which are consistent with proposals to classify the two forms into separate species.

Aims: To determine the similarities and differences in the main biometrical and plumage sex traits between populations of the Iberian Pied Flycatcher Ficedula hypoleuca iberiae and the Atlas Flycatcher Ficedula hypoleuca speculigera.

Methods: Biometric and plumage traits of 193 breeding individuals of Iberian Pied Flycatchers and 43 Atlas Flycatchers were measured in 2014 with standardized protocols.

Results: Both sexes of Atlas Flycatchers were larger than Iberian Pied Flycatchers in skeletal (tarsus) and wing size and also differed in bill morphology, which was wider but shallower in speculigera than iberiae, with females (but not males) having shorter bills than iberiae females. Males differed in mantle colour and forehead patch size, with speculigera males being darker and displaying larger forehead patches than iberiae males. As in populations of iberiae, some speculigera females also expressed a white forehead patch.

Conclusion: We demonstrate significant phenotypic differences between Iberian Pied Flycatchers and Atlas Flycatchers with respect to size and traits of ecological and evolutionary relevance, supporting the recently proposed scenarios on their independent evolution.