Wolbachia in the flesh: symbiont intensities in germ-line and somatic tissues challenge the conventional view of Wolbachia transmission routes

Symbionts can substantially affect the evolution and ecology of their hosts. The investigation of the tissue-specific distribution of symbionts (tissue tropism) can provide important insight into host-symbiont interactions. Among other things, it can help to discern the importance of specific transmission routes and potential phenotypic effects. The intracellular bacterial symbiont Wolbachia has been described as the greatest ever panzootic, due to the wide array of arthropods that it infects. Being primarily vertically transmitted, it is expected that the transmission of Wolbachia would be enhanced by focusing infection in the reproductive tissues. In social insect hosts, this tropism would logically extend to reproductive rather than sterile castes, since the latter constitute a dead-end for vertically transmission. Here, we show that Wolbachia are not focused on reproductive tissues of eusocial insects, and that non-reproductive tissues of queens and workers of the ant Acromyrmex echinatior, harbour substantial infections. In particular, the comparatively high intensities of Wolbachia in the haemolymph, fat body, and faeces, suggest potential for horizontal transmission via parasitoids and the faecal-oral route, or a role for Wolbachia modulating the immune response of this host. It may be that somatic tissues and castes are not the evolutionary dead-end for Wolbachia that is commonly thought

El Servicio de Validación de Copernicus EMS como vector de mejora de la cartografía de emergencias basada en Sentinel

[EN] The Copernicus Emergency Management Service (CEMS) is coordinated by the European Commission and “provides all actors involved in the management of natural disasters, man-made emergency situations, and humanitarian crises with timely and accurate geo-spatial information derived from satellite remote sensing and complemented by available in situ or open data sources”. It includes two components, Early Warning and Monitoring and Mapping. The latter provides on demand geo-spatial information derived from satellite imagery during all phases of the disaster management cycle. It includes 3 systems, Rapid Mapping (RM), Risk and Recovery Mapping (RRM), and a Validation Service. RM provides geospatial information immediately after a disaster to assess its impact; RRM in the prevention, preparation and reconstruction phases; and the Validation Service is in charge of validating and verifying the products generated by both, and of collecting and analyzing users’ feedback. The wide spectrum of activities framed in the Validation Service has allowed it to become a vector to improve the Mapping component through the testing of new methodologies, data input type, or approach for the creation of emergency cartography in the frame of the CEMS. The present paper introduces the main investigation lines based on Sentinel-1 and 2 for flood and fire monitoring that could be implemented in the CEMS services taking into consideration the characteristics of the Mapping component in terms of products to create and time constraints. The applicability of Sentinel-1 for flood monitoring based on the backscattering, the MultiTemporal Coherence (MTC), and dual polarization; and for burnt area delineation based on MTC was studied, while Sentinel-2 was used for burnt area delineation based on vegetation indices. Results indicate that proposed methodologies might be appropriate for the creation of crisis information products in large areas, due to the relative easy and fast implementation compared to classic photo interpretation, although further applicability analyses should be carried out.[ES] El Servicio de Gestión de Emergencias de Copernicus (CEMS), está coordinado por la Comisión Europea y “provee de información geoespacial precisa y oportuna derivada de la teledetección satelital y completada por fuentes de datos disponibles in situ o abiertas a todos los actores involucrados en la gestión de emergencias, bien sean derivadas de desastres naturales o producidos por el hombre, o de crisis humanitarias”. El servicio tiene dos componentes, uno de alerta temprana y monitoreo y otro de creación de mapas. El servicio de mapeo se encarga de proveer, bajo demanda, a los diferentes agentes de emergencias de información geoespacial derivada de imágenes de satélite en todas las fases de la gestión de emergencias, consta de 3 sistemas, Rapid Mapping (RM), Risk and Recovery Mapping (RRM), y Validation. RM aporta información inmediatamente después de un desastre para evaluar su impacto; RRM en las fases de prevención, preparación y reconstrucción; y la Validación se encarga de validar y verificar los productos generados por ambos, y de recoger y analizar los comentarios de los usuarios. El amplio espectro de actividades enmarcadas en él le ha permitido ser vector de mejora de los servicios de mapeo de emergencias mediante el testeo de nuevas metodologías, tipos de datos, o enfoques para la creación de cartografías de emergencias en el marco de CEMS. El presente artículo describe las principales líneas de investigación en el uso de datos Sentinel-1 y 2 para la monitorización de inundaciones e incendios, que se podrían implementar en el futuro en el marco de CEMS. La aplicabilidad de Sentinel-1 para el monitoreo de inundaciones basado en la retrodispersión, la coherencia multitemporal (MTC) y la polarización dual; y se estudió la delimitación del área quemada basada en MTC. Sentinel-2 se usó para delimitar áreas quemadas en base a índices de vegetación. Los resultados indican que las metodologías propuestas podrían ser apropiadas para la creación de productos de información de crisis en grandes áreas, debido a la implementación relativamente fácil y rápida en comparación con la fotointerpretación clásica, aunque deberían realizarse más análisis para su aplicación en el marco de CEMS.The authors gratefully acknowledge the contribution of Massimiliano Rossi and Antigoni Maistrali for the preparation of the materials analysed in this work.Donezar-Hoyos, U.; Albizua-Huarte, L.; Amezketa-Lizarraga, E.; Barinagarrementeria-Arrese, I.; Ciriza, R.; De Blas-Corral, T.; Larrañaga-Urien, A.... (2020). The Copernicus EMS Validation service as a vector for improving the emergency mapping based on Sentinel data. Revista de Teledetección. 0(56):23-34. https://doi.org/10.4995/raet.2020.13770OJS233405

Real-world evidence on non-invasive tests and associated cut-offs used to assess fibrosis in routine clinical practice

Background & Aims: Non-invasive tests (NITs) offer a practical solution for advanced fibrosis identification in non-alcoholic fatty liver disease (NAFLD). Despite increasing implementation, their use is not standardised, which can lead to inconsistent interpretation and risk stratification. We aimed to assess the types of NITs and the corresponding cut-offs used in a range of healthcare settings. / Methods: A survey was distributed to a convenience sample of liver health experts who participated in a global NAFLD consensus statement. Respondents provided information on the NITs used in their clinic with the corresponding cut-offs and those used in established care pathways in their areas. / Results: There were 35 respondents from 24 countries, 89% of whom practised in tertiary level settings. A total of 14 different NITs were used, and each respondent reported using at least one (median = 3). Of the respondents, 80% reported using FIB-4 and liver stiffness by vibration-controlled transient elastography (Fibroscan®), followed by the NAFLD fibrosis score (49%). For FIB-4, 71% of respondents used a low cut-off of 7.5 to >20 kPa, respectively). / Conclusions: The cut-offs used for the same NITs for NAFLD risk stratification vary between clinicians. As cut-offs impact test performance, these findings underscore the heterogeneity in risk-assessment and support the importance of establishing consistent guidelines on the standardised use of NITs in NAFLD management. / Lay summary: Owing to the high prevalence of non-alcoholic fatty liver disease (NAFLD) in the general population it is important to identify those who have more advanced stages of liver fibrosis, so that they can be properly treated. Non-invasive tests (NITs) provide a practical way to assess fibrosis risk in patients. However, we found that the cut-offs used for the same NITs vary between clinicians. As cut-offs impact test performance, these findings highlight the importance of establishing consistent guidelines on the standardised use of NITs to optimise clinical management of NAFLD

Biomagnifcation and body distribution of ivermectin in dung beetles

We thank the staf of Doñana Biological Reserve (DBR-ICTS), Doñana National Park, and Los Alcornocales Natural Park, especially D. Paz, F. Ibáñez, P. Bayón, M. Malla and D. Ruiz for logistic facilities for the field work and permissions (2019107300000904/IRM/MDCG/mes) to collect cattle dung and dung beetles. We are grateful to J. Castro and A. Rascón for technical assistance. We also thank A. V. Giménez-Gómez for her technical assistance in the laboratory work. We thank also F.-T Krell and the two anonymous reviewers for their constructive comments. Financial support was provided by the project CGL2015-68207-R of the Secretaría de Estado de Investigación–Ministerio de Economía y Competitividad.A terrestrial test system to investigate the biomagnifcation potential and tissue-specifc distribution of ivermectin, a widely used parasiticide, in the non-target dung beetle Thorectes lusitanicus (Jekel) was developed and validated. Biomagnifcation kinetics of ivermectin in T. lusitanicus was investigated by following uptake, elimination, and distribution of the compound in dung beetles feeding on contaminated faeces. Results showed that ivermectin was biomagnifed in adults of T. lusitanicus when exposed to non-lethal doses via food uptake. Ivermectin was quickly transferred from the gut to the haemolymph, generating a biomagnifcation factor (BMFk) three times higher in the haemolymph than in the gut after an uptake period of 12 days. The fat body appeared to exert a major role on the biomagnifcation of ivermectin in the insect body, showing a BMFk 1.6 times higher than in the haemolymph. The results of this study highlight that the biomagnifcation of ivermectin should be investigated from a global dung-based food web perspective and that the use of these antiparasitic substances should be monitored and controlled on a precautionary basis. Thus, we suggest that an additional efort be made in the development of standardised regulatory recommendations to guide biomagnifcation studies in terrestrial organisms, but also that it is necessary to adapt existing methods to assess the efects of such veterinary medical products

Metabolic Factors Limiting Performance in Marathon Runners

Each year in the past three decades has seen hundreds of thousands of runners register to run a major marathon. Of those who attempt to race over the marathon distance of 26 miles and 385 yards (42.195 kilometers), more than two-fifths experience severe and performance-limiting depletion of physiologic carbohydrate reserves (a phenomenon known as ‘hitting the wall’), and thousands drop out before reaching the finish lines (approximately 1–2% of those who start). Analyses of endurance physiology have often either used coarse approximations to suggest that human glycogen reserves are insufficient to fuel a marathon (making ‘hitting the wall’ seem inevitable), or implied that maximal glycogen loading is required in order to complete a marathon without ‘hitting the wall.’ The present computational study demonstrates that the energetic constraints on endurance runners are more subtle, and depend on several physiologic variables including the muscle mass distribution, liver and muscle glycogen densities, and running speed (exercise intensity as a fraction of aerobic capacity) of individual runners, in personalized but nevertheless quantifiable and predictable ways. The analytic approach presented here is used to estimate the distance at which runners will exhaust their glycogen stores as a function of running intensity. In so doing it also provides a basis for guidelines ensuring the safety and optimizing the performance of endurance runners, both by setting personally appropriate paces and by prescribing midrace fueling requirements for avoiding ‘the wall.’ The present analysis also sheds physiologically principled light on important standards in marathon running that until now have remained empirically defined: The qualifying times for the Boston Marathon

The Major Yolk Protein Vitellogenin Interferes with the Anti-Plasmodium Response in the Malaria Mosquito Anopheles gambiae

Functional gene analysis in malaria mosquitoes reveals molecules underpinning the trade-off between efficient reproduction and the antiparasitic response

The Crystal Structure and RNA-Binding of an Orthomyxovirus Nucleoprotein

Genome packaging for viruses with segmented genomes is often a complex problem. This is particularly true for influenza viruses and other orthomyxoviruses, whose genome consists of multiple negative-sense RNAs encapsidated as ribonucleoprotein (RNP) complexes. To better understand the structural features of orthomyxovirus RNPs that allow them to be packaged, we determined the crystal structure of the nucleoprotein (NP) of a fish orthomyxovirus, the infectious salmon anemia virus (ISAV) (genus Isavirus). As the major protein component of the RNPs, ISAV-NP possesses a bi-lobular structure similar to the influenza virus NP. Because both RNA-free and RNA-bound ISAV NP forms stable dimers in solution, we were able to measure the NP RNA binding affinity as well as the stoichiometry using recombinant proteins and synthetic oligos. Our RNA binding analysis revealed that each ISAV-NP binds ,12 nts of RNA, shorter than the 24ﾖ28 nts originally estimated for the influenza A virus NP based on population average. The 12-nt stoichiometry was further confirmed by results from electron microscopy and dynamic light scattering. Considering that RNPs of ISAV and the influenza viruses have similar morphologies and dimensions, our findings suggest that NP-free RNA may exist on orthomyxovirus RNPs, and selective RNP packaging may be accomplished through direct RNA-RNA interactions

An RGS-Containing Sorting Nexin Controls Drosophila Lifespan

The pursuit of eternal youth has existed for centuries and recent data indicate that fat-storing tissues control lifespan. In a D. melanogaster fat body insertional mutagenic enhancer trap screen designed to isolate genes that control longevity, we identified a regulator of G protein signaling (RGS) domain containing sorting nexin, termed snazarus (sorting nexin lazarus, snz). Flies with insertions into the 5′ UTR of snz live up to twice as long as controls. Transgenic expression of UAS-Snz from the snz Gal4 enhancer trap insertion, active in fat metabolic tissues, rescued lifespan extension. Further, the lifespan extension of snz mutants was independent of endosymbiont, e.g., Wolbachia, effects. Notably, old snz mutant flies remain active and fertile indicating that snz mutants have prolonged youthfulness, a goal of aging research. Since mammals have snz-related genes, it is possible that the functions of the snz family may be conserved to humans