Trichinella britovi etiological agent of sylvatic trichinellosis in the Republic of Guinea (West Africa) and a re-evaluation of geographical distribution for encapsulated species in Africa

In West Africa, Trichinella infection was documented in humans and animals from Senegal in the 1960s, and the biological characters of one isolate showed a lower infectivity to domestic pigs and rodents when compared with that of a Trichinella spiralis pig isolate from Europe. To identify the Trichinella species present in West Africa, a survey was conducted in a total of 160 wild animals in the Republic of Guinea. Three Viverridae, one true civet (Viverra civetta) and two African palm civets (Nandinia binotata) from the Fouta Djallon Massif, Pilimini Subprefecture, were found positive by artificial digestion of muscle samples. Trichinella larvae from these three viverrids were identified as Trichinella britovi and no difference was detected in three examined sequences from these African isolates and the reference strain of T. britovi from Europe, indicating common ancestry, an historically continuous geographic distribution, and recent isolation for African and European populations. The detection of T. britovi in West Africa modifies our knowledge about the distribution of encapsulated species of Trichinella in Africa. Thus, Trichinella nelsoni is now considered to have a distribution limited to the Eastern part of the Afrotropical region from Kenya to South Africa. This provides a plausible explanation for the presence of Trichinella T8 in Namibia and South Africa, and further suggests that T. britovi could be the Trichinella species circulating among wild animals of Northern Africa

Relationship between sperm quality parameters and fatty acid composition of the muscle, liver and testis of European eel

[EN] This study looks at the correlations that fatty acids have with different tissues in the European eel (Anguilla anguilla L.) during hormonally-induced sexual maturation, with different sperm quality parameters. In order to evaluate the different dynamics of the use of fatty acids, a categorization of the results from each sperm quality parameter (volume, concentration, motility and velocity) was performed. Low and moderate correlations were observed between muscle tissue and some sperm quality parameters but no high correlations were found. Eicosapentaenoic add (20:5n3, EPA) in the liver seems to have a role in determining the volume of sperm produced. This can be explained by the fact that EPA is a major requirement in the early phases of sperm production (probably as a component of the spermatozoal membrane). In addition, the levels of alpha-linolenic acid (18:3-n3, ALA) and linoleic acid (18:2-n6, LA) in the liver decreased when sperm motility increased. In all the tissues, a negative correlation was observed between arachidonic acid (20:4n-6, ARA) and the different sperm velocity parameters. The fact that an increase in the consumption of ARA coincides with an increase in the speed of spermatozoa, highlights the important role that this fatty acid plays not only in sperm production, but also in sperm velocity. All this information could prove useful in the development of suitable broodstock diets to improve sperm quality and subsequently, the larval development of this species. (C) 2014 Elsevier Inc All rights reserved.This work was funded by the European Community's Seventh Framework Programme under the Theme 2 "Food, Agriculture and Fisheries, and Biotechnology", grant agreement no. 245257 (PRO-EEL), and COST Office (Food and Agriculture COST Action FA1205: AQUAGAMETE). Victor Gallego, Ilaria Mazzeo and M. Carmen Vilchez had predoctoral grants from the Spanish Ministry of Science and Innovation (MICINN), Generalitat Valenciana, and UPV PAID Programme (2011-S2-02-6521), respectively. David S. Penaranda was supported by a contract co-financed by MICINN and UPV (PTA2011-4948-I). Rosa Baeza was supported by a contract funded by PRO-EEL. Authors want to thank Vicente Javier Moya Salvador for his technical assistance with gas chromatography analyses.Baeza Ariño, R.; Mazzeo, I.; Vilchez Olivencia, MC.; Gallego Albiach, V.; Peñaranda, D.; Pérez Igualada, LM.; Asturiano Nemesio, JF. (2015). Relationship between sperm quality parameters and fatty acid composition of the muscle, liver and testis of European eel. Comparative Biochemistry and Physiology - Part A: Molecular and Integrative Physiology. 181:79-86. https://doi.org/10.1016/j.cbpa.2014.11.022S798618

Effect of thermal regime on fatty acid dynamics in male European eels (Anguilla anguilla) during hormonally-induced spermatogenesis

[EN] Little is known about the role of fat and fatty acids in European eel spermatogenesis. The aim of this research was to study the changes in fat content and to carry out a quantitative analysis of the fatty acid composition of the muscle, liver and gonad of European male eels during hormonally induced sexual maturation. Three different thermal regimes were used (two variable: T10 and T15; and one constant: T20) to replicate the changes in temperature that these fish experience during their transoceanic reproductive migration. Spermatogenesis was reached earlier in treatment T20, suggesting that spermatogenesis in the European eel is closely regulated by water temperature. Although eels lose body mass due to the period of fasting that accompanies gonadal growth, no significant changes were found in the fat and fatty acid content of the muscle during the experimental period. With regard to the liver, the levels of palmitic, eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids increased significantly at the start of the spermiation process in all the thermal treatments. In the testis, levels of EPA, arachidonic acid (ARA) and DHA remained constant during the maturation process whereas the levels of the rest of the fatty acids decreased significantly. The stability of the ARA and EPA levels in the testis may have a physiological significance, whereas the stability of the DHA levels may have a structural significance. The results suggest that the progression of spermiation is influenced by water temperature and demonstrate the importance of EPA, ARA and DHA in European eel reproduction. This study demonstrates that complementary research focusing on the lipid composition of commercial diets could improve the sperm quality of this species.Funded by the European Community's 7th Framework Programme under the Theme 2 "Food, Agriculture and Fisheries, and Biotechnology", grant agreement no. 245257 (PRO-EEL). Victor Gallego, Ilaria Mazzeo and M. Carmen Vilchez had predoctoral grants from the Spanish Ministry of Science and Innovation (MICINN), Generalitat Valenciana, and UPV PAID Programme (2011-S2-02-6521), respectively. David S. Penaranda was supported by a contract co-financed by MICINN and UPV (PTA2011-4948-I). Rosa Baeza was supported by contract financed by PRO-EEL. The authors want to thank Vicente Javier Moya Salvador for his technical assistance with gas chromatography analyses.Baeza Ariño, R.; Mazzeo, I.; Vilchez Olivencia, MC.; Gallego Albiach, V.; Peñaranda, D.; Pérez Igualada, LM.; Asturiano Nemesio, JF. (2014). Effect of thermal regime on fatty acid dynamics in male European eels (Anguilla anguilla) during hormonally-induced spermatogenesis. Aquaculture. 430:86-97. https://doi.org/10.1016/j.aquaculture.2014.03.045S869743

RimNet: A deep 3D multimodal MRI architecture for paramagnetic rim lesion assessment in multiple sclerosis.

In multiple sclerosis (MS), the presence of a paramagnetic rim at the edge of non-gadolinium-enhancing lesions indicates perilesional chronic inflammation. Patients featuring a higher paramagnetic rim lesion burden tend to have more aggressive disease. The objective of this study was to develop and evaluate a convolutional neural network (CNN) architecture (RimNet) for automated detection of paramagnetic rim lesions in MS employing multiple magnetic resonance (MR) imaging contrasts. Imaging data were acquired at 3 Tesla on three different scanners from two different centers, totaling 124 MS patients, and studied retrospectively. Paramagnetic rim lesion detection was independently assessed by two expert raters on T2*-phase images, yielding 462 rim-positive (rim+) and 4857 rim-negative (rim-) lesions. RimNet was designed using 3D patches centered on candidate lesions in 3D-EPI phase and 3D FLAIR as input to two network branches. The interconnection of branches at both the first network blocks and the last fully connected layers favors the extraction of low and high-level multimodal features, respectively. RimNet's performance was quantitatively evaluated against experts' evaluation from both lesion-wise and patient-wise perspectives. For the latter, patients were categorized based on a clinically relevant threshold of 4 rim+ lesions per patient. The individual prediction capabilities of the images were also explored and compared (DeLong test) by testing a CNN trained with one image as input (unimodal). The unimodal exploration showed the superior performance of 3D-EPI phase and 3D-EPI magnitude images in the rim+/- classification task (AUC = 0.913 and 0.901), compared to the 3D FLAIR (AUC = 0.855, Ps < 0.0001). The proposed multimodal RimNet prototype clearly outperformed the best unimodal approach (AUC = 0.943, P < 0.0001). The sensitivity and specificity achieved by RimNet (70.6% and 94.9%, respectively) are comparable to those of experts at the lesion level. In the patient-wise analysis, RimNet performed with an accuracy of 89.5% and a Dice coefficient (or F1 score) of 83.5%. The proposed prototype showed promising performance, supporting the usage of RimNet for speeding up and standardizing the paramagnetic rim lesions analysis in MS

Charged-Particle Multiplicities in Charged-Current Neutrino-- and Anti-Neutrino--Nucleus Interactions

The CHORUS experiment, designed to search for $\nu_{\mu}\to\nu_{\tau}$ oscillations, consists of a nuclear emulsion target and electronic detectors. In this paper, results on the production of charged particles in a small sample of charged-current neutrino-- and anti-neutrino--nucleus interactions at high energy are presented. For each event, the emission angle and the ionization features of the charged particles produced in the interaction are recorded, while the standard kinematic variables are reconstructed using the electronic detectors. The average multiplicities for charged tracks, the pseudo-rapidity distributions, the dispersion in the multiplicity of charged particles and the KNO scaling are studied in different kinematical regions. A study of quasi-elastic topologies performed for the first time in nuclear emulsions is also reported. The results are presented in a form suitable for use in the validation of Monte Carlo generators of neutrino--nucleus interactions.Comment: 17 pages, 5 figure

Computer Simulations of Hippocampal Mossy Fiber Cleft Zinc Movements

Zinc ions have key regulatory, structural, and catalytic functions and mediate a variety of intra- and intercellular processes. The hippocampal mossy fiber boutons contain large amounts of free or loosely bound vesicular zinc, which can be co-released with glutamate. Zinc can interact with a variety of ionic channels (N-VDCCs, L-VDCCs, KATP), glutamate receptors (AMPA, KA, NMDA 2A, 2B), glutamate transporters (GLAST, EAAT4), and molecules (ATP). The dynamic properties of cleft free, complexed, and total zinc were addressed, considering the known concentration and affinity of various cleft zinc sensitive sites, mainly in the postsynaptic area and in glial cells. The computer model included three different zinc release processes, with short, medium, and long duration, described, like the uptake ones, by alpha functions. The results suggest that, depending on the amount of release, zinc clearance is largely due, either, to zinc binding to NMDA 2A receptor sites or to glial GLAST transporters

Pulsar-wind nebulae and magnetar outflows: observations at radio, X-ray, and gamma-ray wavelengths

We review observations of several classes of neutron-star-powered outflows: pulsar-wind nebulae (PWNe) inside shell supernova remnants (SNRs), PWNe interacting directly with interstellar medium (ISM), and magnetar-powered outflows. We describe radio, X-ray, and gamma-ray observations of PWNe, focusing first on integrated spectral-energy distributions (SEDs) and global spectral properties. High-resolution X-ray imaging of PWNe shows a bewildering array of morphologies, with jets, trails, and other structures. Several of the 23 so far identified magnetars show evidence for continuous or sporadic emission of material, sometimes associated with giant flares, and a few possible "magnetar-wind nebulae" have been recently identified.Comment: 61 pages, 44 figures (reduced in quality for size reasons). Published in Space Science Reviews, "Jets and Winds in Pulsar Wind Nebulae, Gamma-ray Bursts and Blazars: Physics of Extreme Energy Release