Molecular mechanism for the subversion of the retromer coat by the Legionella effector RidL

Microbial pathogens employ sophisticated virulence strategies to cause infections in humans. The intracellular pathogen Legionella pneumophila encodes RidL to hijack the host scaffold protein VPS29, a component of retromer and retriever complexes critical for endosomal cargo recycling. Here, we determined the crystal structure of L. pneumophila RidL in complex with the human VPS29?VPS35 retromer subcomplex. A hairpin loop protruding from RidL inserts into a conserved pocket on VPS29 that is also used by cellular ligands, such as Tre-2/Bub2/Cdc16 domain family member 5 (TBC1D5) and VPS9-ankyrin repeat protein for VPS29 binding. Consistent with the idea of molecular mimicry in protein interactions, RidL outcompeted TBC1D5 for binding to VPS29. Furthermore, the interaction of RidL with retromer did not interfere with retromer dimerization but was essential for association of RidL with retromer-coated vacuolar and tubular endosomes. Our work thus provides structural and mechanistic evidence into how RidL is targeted to endosomal membranes.ACKNOWLEDGMENTS: We thank Ander Vidaurrazaga (Centro de Investigación Cooperativa en Biociencias) for technical assistance and Devanand Bondage (National Institute of Child Health and Human Development) for proliferation assays of Legionella pneumophila. This study made use of the Diamond Light Source (Oxfordshire, United Kingdom), the European Synchrotron Radiation Facility (Grenoble, France), and the ALBA synchrotron beamline BL13-XALOC, funded in part by the Horizon 2020 programme of the European Union, iNEXT (H2020 Grant 653706). We thank all the staff from these facilities for technical and human support. This work was supported by the Spanish Ministry of Economy and Competitiveness Grant BFU2014-59759-R (to A.H.); the Severo Ochoa Excellence Accreditation SEV-2016-0644; and the Intramural Program of the Eunice Kennedy Shriver National Institute of Child Health and Human development (Projects ZIA HD001607 and ZIA HD008893). M.R.-M. is supported by a pre-doctoral fellowship from the Basque Government (PRE_2016_2_0249)

Quantification of 3α-hydroxytibolone in human plasma by high performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS): Application in a bioequivalence study in healthy postmenopausal volunteers

Abstract A sensitive, specific and fast method to quantify 3α-hydroxytibolone in human plasma using deuterated 3α-hydroxytibolone (d5) as internal standard is described. The analyte and the internal standard were extracted from plasma (900 μL) by liquid-liquid extraction using ethyl ether/hexane (50/50, v/v) and ammonium hydroxide (50%). The extracts were analyzed by high performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry without derivatization. Chromatography was performed isocratically on a Gemini-NX™ C18 5 μm (150 × 4.6 mm i. d.) column. The method had a chromatographic run time of 3.75 min and a linear calibration curve over the range 1–100 ng/mL. The limit of quantification validated was 1 ng/mL. This method was used to assess the bioequivalence between two different tibolone oral formulations: Livolon (1.25 mg tablet) provided by Biolab Sanus Farmaceutica (Brazil), as the test formulation, and Libiam™ (1.25 mg tablet) produced by Libbs Farmaceutica (Brazil), as the reference formulation. A single 3.75 mg dose of each formulation was administered to 46 postmenopausal female healthy volunteers. The study was conducted in an open, randomized, two-period crossover balanced design with a 2 week washout interval between the doses. The 90% confidence interval for Cmax, AUC(0-last) and AUC(0-inf) individual test/reference ratios were 97.48–111.51, 95.35–103.20 and 96.42–103.86, respectively. It is concluded that Livolon (1.25 mg tablet) is bioequivalent to Libiam™ (1.25 mg tablet), with regards to both rate and extent of absorption

Feigenbaum graphs: a complex network perspective of chaos

The recently formulated theory of horizontal visibility graphs transforms time series into graphs and allows the possibility of studying dynamical systems through the characterization of their associated networks. This method leads to a natural graph-theoretical description of nonlinear systems with qualities in the spirit of symbolic dynamics. We support our claim via the case study of the period-doubling and band-splitting attractor cascades that characterize unimodal maps. We provide a universal analytical description of this classic scenario in terms of the horizontal visibility graphs associated with the dynamics within the attractors, that we call Feigenbaum graphs, independent of map nonlinearity or other particulars. We derive exact results for their degree distribution and related quantities, recast them in the context of the renormalization group and find that its fixed points coincide with those of network entropy optimization. Furthermore, we show that the network entropy mimics the Lyapunov exponent of the map independently of its sign, hinting at a Pesin-like relation equally valid out of chaos.Comment: Published in PLoS ONE (Sep 2011

CDC42EP5/BORG3 modulates SEPT9 to promote actomyosin function, migration, and invasion.

Fast amoeboid migration is critical for developmental processes and can be hijacked by cancer cells to enhance metastatic dissemination. This migratory behavior is tightly controlled by high levels of actomyosin contractility, but how it is coupled to other cytoskeletal components is poorly understood. Septins are increasingly recognized as novel cytoskeletal components, but details on their regulation and contribution to migration are lacking. Here, we show that the septin regulator Cdc42EP5 is consistently required for amoeboid melanoma cells to invade and migrate into collagen-rich matrices and locally invade and disseminate in vivo. Cdc42EP5 associates with actin structures, leading to increased actomyosin contractility and amoeboid migration. Cdc42EP5 affects these functions through SEPT9-dependent F-actin cross-linking, which enables the generation of F-actin bundles required for the sustained stabilization of highly contractile actomyosin structures. This study provides evidence that Cdc42EP5 is a regulator of cancer cell motility that coordinates actin and septin networks and describes a unique role for SEPT9 in melanoma invasion and metastasis

Fetal Liver Volume Assessment Using Magnetic Resonance Imaging in Fetuses With Cytomegalovirus Infection

Objective: To assess fetal liver volume (FLV) by magnetic resonance imaging (MRI) in cytomegalovirus (CMV)-infected fetuses compared to a group of healthy fetuses. Method: Most infected cases were diagnosed by the evidence of ultrasound abnormalities during routine scans and in some after maternal CMV screening. CMV-infected fetuses were considered severely or mildly affected according to prenatal brain lesions identified by ultrasound (US)/MRI. We assessed FLV, the FLV to abdominal circumference (AC) ratio (FLV/AC-ratio), and the FLV to fetal body volume (FBV) ratio (FLV/FBV-ratio). As controls, we included 33 healthy fetuses. Hepatomegaly was evaluated post-mortem in 11 cases of congenital CMV infection. Parametric trend and intraclass correlation analyses were performed. Results: There were no significant differences in FLV between infected (n = 32) and healthy fetuses. On correcting the FLV for AC and FBV, we observed a significantly higher FLV in CMV-infected fetuses. There were no significant differences in the FLV, or the FLV/AC or FLV/FBV-ratios according to the severity of brain abnormalities. There was excellent concordance between the fetal liver weight estimated by MRI and liver weight obtained post-mortem. Hepatomegaly was not detected in any CMV-infected fetus. Conclusion: In CMV-infected fetuses, FLV corrected for AC and FBV was higher compared to healthy controls, indicating relative hepatomegaly. These parameters could potentially be used as surrogate markers of liver enlargement. Keywords: fetal brain abnormalities; fetal cytomegalovirus infection; fetal liver; magnetic resonance imaging; pregnancy

Projecting Global Biodiversity Indicators under Future Development Scenarios

To address the ongoing global biodiversity crisis, governments have set strategic objectives and have adopted indicators to monitor progress toward their achievement. Projecting the likely impacts on biodiversity of different policy decisions allows decision makers to understand if and how these targets can be met. We projected trends in two widely used indicators of population abundance Geometric Mean Abundance, equivalent to the Living Planet Index and extinction risk (the Red List Index) under different climate and land-use change scenarios. Testing these on terrestrial carnivore and ungulate species, we found that both indicators decline steadily, and by 2050, under a Business-as-usual (BAU) scenario, geometric mean population abundance declines by 18-35% while extinction risk increases for 8-23% of the species, depending on assumptions about species responses to climate change. BAU will therefore fail Convention on Biological Diversity target 12 of improving the conservation status of known threatened species. An alternative sustainable development scenario reduces both extinction risk and population losses compared with BAU and could lead to population increases. Our approach to model species responses to global changes brings the focus of scenarios directly to the species level, thus taking into account an additional dimension of biodiversity and paving the way for including stronger ecological foundations into future biodiversity scenario assessments.Peer reviewe

Aerosol lidar intercomparison in the framework of SPALINET- the SPAnish LIdar NETwork: methodology and results

A group of eight Spanish lidars was formed in order to extend the European Aerosol Research Lidar Network-Advanced Sustainable Observation System (EARLINET-ASOS) project. This study presents intercomparisons at the hardware and software levels. Results of the system intercomparisons are based on range-square-corrected signals in cases where the lidars viewed the same atmospheres. Comparisons were also made for aerosol backscatter coefficients at 1064 nm (2 systems) and 532 nm (all systems), and for extinction coefficients at 532 nm (2 systems). In total, three field campaigns were carried out between 2006 and 2007. Comparisons were limited to the highest layer found before the free troposphere, i.e., either the atmospheric boundary layer or the aerosol layer just above it. Some groups did not pass the quality assurance criterion on the first attempt. Following modification and improvement to these systems, all systems met the quality criterion. The backscatter algorithm intercomparison consisted of processing lidar signal profiles simulated for two types of atmospheric conditions. Three stages with increasing knowledge of the input parameters were considered. The results showed that all algorithms work well when all inputs are known. They also showed the necessity to perform, when possible, additional measurements to attain better estimation of the lidar ratio, which is the most critical unknown in the elastic lidar inversion

Lithium and Halpha in stars and brown dwarfs of sigma Orionis

We present intermediate- and low-resolution optical spectra around Halpha and LiI 6708 A for a sample of 25 low mass stars and 2 brown dwarfs with confirmed membership in the pre-main sequence stellar sigma Orionis cluster. Our observations are intended to investigate the age of the cluster. The spectral types derived for our target sample are found to be in the range K6-M8.5, which corresponds to a mass interval of roughly 1.2-0.02 Msun on the basis of state-of-the-art evolutionary models. Radial velocities (except for one object) are found to be consistent with membership in the Orion complex. All cluster members show considerable Halpha emission and LiI in absorption, which is typical of very young ages. We find that our pseudo-equivalent widths appear rather dispersed (and intense in the case of Halpha) for objects cooler than M3.5 spectral class, occurring at the approximate mass where low mass stars are expected to become fully convective. The least massive brown dwarf in our sample, SOri 45 (M8.5, ~0.02 Msun), displays variable Halpha emission and a radial velocity that differs from the cluster mean velocity. Tentative detection of forbidden lines in emission indicates that this brown dwarf may be accreting mass from a surrounding disk. We also present recent computations of LiI curves of growth for low gravities and for the temperature interval (about 4000-2600 K) of our sample. The comparison of our observations to these computations allows us to infer that no lithium depletion has yet taken place in sigma Orionis, and that the observed pseudo-equivalent widths are consistent with a cluster initial lithium abundance close to the cosmic value. Hence, the upper limit to the sigma Orionis cluster age can be set at 8 Myr, with a most likely value around 2-4 Myr.Comment: 17 pages (figures included). Accepted for publication in A&

Inmunoterapia con células CAR-T en hematooncología pediátrica

Resumen A pesar de ser una enfermedad rara, el cáncer es la primera causa de mortalidad por enfermedad durante la edad pediátrica en los países desarrollados. En este momento, la irrupción de nuevos tratamientos como la inmunoterapia constituye un nuevo paradigma clínico y regulatorio. Uno de estos tipos de inmunoterapia es la inmunoterapia celular. En particular, los medicamentos de terapia avanzada con receptores antigénicos quiméricos en los linfocitos T (CAR-T), y en concreto las células CAR-T19, han supuesto un nuevo escenario en el abordaje de los tumores hematológicos, como la leucemia aguda linfoblástica y los linfomas de células tipo B. La aprobación por las autoridades regulatorias de tisagenlecleucel y axicabtagene ciloleucel, ha impulsado la puesta en marcha del Plan Nacional de Terapias Avanzadas-Medicamentos CART en Espana, ˜ evidenciándose no solo la conveniencia de identificar los centros más adecuados para su administración, sino la necesidad de que estos sufran una profunda transformación para que su actividad asistencial se extienda en algunos casos a la capacidad de fabricación propia de este tipo de terapias. Los hospitales especializados en hematooncología pediátrica tienen por tanto el reto de evolucionar hacia un modelo asistencial que integre la inmunoterapia celular, dotándose de capacidad propia para gestionar todos los aspectos relativos al uso, fabricación y administración de estos nuevos tratamientos.Abstract Despite being a rare disease, cancer is the first cause of mortality due to disease during the paediatric age in the developed countries. The current, great increase in new treatments, such as immunotherapy, constitutes a new clinical and regulatory paradigm. Cellular immunotherapy is one of these types of immunotherapy. In particular, the advanced therapy drugs with chimeric antigen receptors in the T-lymphocytes (CAR-T), and particularly the CART19 cells, has opened up a new scenario in the approach to haematology tumours like acute lymphoblastic leukaemia and the B-Cell lymphomas. The approval of tisagenlecleucel and axicabtagene ciloleucel by the regulatory authorities has led to the setting up of the National Plan for Advanced Therapies-CAR-T drugs in Spain. There is evidence of, not only the advantage of identifying the centres most suitable for their administration, but also the need for these to undergo a profound change in order that their healthcare activity is extended, in some cases, to the ability for the in-house manufacture of these types of therapies. The hospitals specialised in paediatric haematology-oncology thus have the challenge of progressing towards a healthcare model that integrates cellular immunotherapy, having the appropriate capacity to manage all aspects relative to their use, manufacture, and administration of these new treatments