Red nucleus and rubrospinal tract disorganization in the absence of Pou4f1

The red nucleus (RN) is a neuronal population that plays an important role in forelimb motor control and locomotion. Histologically it is subdivided into two subpopulations, the parvocellular RN (pRN) located in the diencephalon and the magnocellular RN (mRN) in the mesencephalon. The RN integrates signals from motor cortex and cerebellum and projects to spinal cord interneurons and motor neurons through the rubrospinal tract (RST). Pou4f1 is a transcription factor highly expressed in this nucleus that has been related to its specification. Here we profoundly analyzed consequences of Pou4f1 loss-of-function in development, maturation and axonal projection of the RN. Surprisingly, RN neurons are specified and maintained in the mutant, no cell death was detected. Nevertheless, the nucleus appeared disorganized with a strong delay in radial migration and with a wider neuronal distribution; the neurons did not form a compacted population as they do in controls, Robo1 and Slit2 were miss-expressed. Cplx1 and Npas1, expressed in the RN, are transcription factors involved in neurotransmitter release, neuronal maturation and motor function processes among others. In our mutant mice, both transcription factors are lost, suggesting an abnormal maturation of the RN. The resulting altered nucleus occupied a wider territory. Finally, we examined RST development and found that the RN neurons were able to project to the spinal cord but their axons appeared defasciculated. These data suggest that Pou4f1 is necessary for the maturation of RN neurons but not for their specification and maintenance.Peer reviewedPeer Reviewe

Characterization of Tajogaite volcanic plumes detected over the Iberian Peninsula from a set of satellite and ground-based remote sensing instrumentation

Three volcanic plumes were detected during the Tajogaite volcano eruptive activity (Canary Islands, Spain, September–December 2021) over the Iberian Peninsula. The spatiotemporal evolution of these events is characterised by combining passive satellite remote sensing and ground-based lidar and sun-photometer systems. The inversion algorithm GRASP is used with a suite of ground-based remote sensing instruments such as lidar/ceilometer and sun-photometer from eight sites at different locations throughout the Iberian Peninsula. Satellite observations showed that the volcanic ash plumes remained nearby the Canary Islands covering a mean area of 120 ± 202 km2 during the whole period of eruptive activity and that sulphur dioxide plumes reached the Iberian Peninsula. Remote sensing observations showed that the three events were mainly composed of sulphates, which were transported from the volcano into the free troposphere. The high backscatter-related Ångström exponents for wavelengths 532–1064 nm (1.17 ± 0.20 to 1.40 ± 0.24) and low particle depolarization ratios (0.08 ± 0.02 to 0.09 ± 0.02), measured by the multi-wavelength Raman lidar, hinted at the presence of spherical small particles. The layer aerosol optical depth at 532 nm (AODL532) obtained from lidar measurements contributed between 49% and 82% to the AERONET total column AOD at 532 nm in event II (11–13 October). According to the GRASP retrievals, the layer aerosol optical depth at 440 nm (AODL440) was higher in all sites during event II with values between 0.097 (Badajoz) and 0.233 (Guadiana-UGR) and lower in event III (19–21 October) varying between 0.003 (Granada) and 0.026 (Évora). Compared with the GRASP retrievals of total column AOD at 440 nm, the AODL440 had contributions between 21% and 52% during event II. In the event I (25–28 September), the mean volume concentrations (VC) varied between 5 ± 4 μm3cm−3 (El-Arenosillo/Huelva) and 17 ± 10 μm3cm−3 (Guadiana-UGR), while in event II this variation was from 11 ± 7 μm3cm−3 (Badajoz) to 27 ± 10 μm3cm−3 (Guadiana-UGR). Due to the impact of volcanic events on atmospheric and economic fields, such as radiative forcing and airspace security, a proper characterization is required. This work undertakes it using advanced instrumentation and methods.PROBE Cost Action - NASA Ra-diation Sciences Program and Earth Observing System UIDB/04683/2020National funds through FCT -Fundacao para a Ciencia e Tecnologia, I.P., in the framework of the ICT project UIDB/04683/2020 UIDP/04683/2020TOMA-QAPA PTDC/CTAMET/29678/2017GRASP-ACE 778349ACTRIS-IMP 871115ATMO-ACCESS 101008004PROBE CA18235HARMONIA CA21119EUMETNET through the E-PROFILE program and REALISTIC 101086690ACTRIS-2 654109Spanish Government PID2019-103886RB-I00/AEI/10.13039/501100011033NTEGRATYON3 PID2020-117825GB-C21 PID2020-117825GB- C22ELPIS PID2020-120015RB-I00CLARIN CGL2016-81092-REPOLAAR RTI2018-097864-B-I00CAMELIA PID2019-104205GB- C21/AEI/10.13039/501100011033ACTRIS-Espa ~na CGL2017- 90884REDTUniversity of Granada Plan Propio through Singular Laboratory LS2022-1Andalusia Autonomous Government projects AEROPRE and ADAPNE P18-RT-3820 P20_00136UGR-FEDER projects DEM3TRIOS A-RNM-524-UGR20MOGATRACO UCE-PP2017-02Scientific Units of Excellence Program RTI 2018-097332-B-C22R+D+i grant MCIN/AEI/ 10.13039/ 501100011033ERDF A Way of Doing EuropeINTA predoctoral contract program A-RNM-430-UGR2

Extinction-related Angström exponent characterization of submicrometric volume fraction in atmospheric aerosol particles

The AEAOD– ΔAEAOD grid proposed by Gobbi et al. (2007) is a graphical method used to visually represent the spectral characterization of aerosol optical depth (AOD), i.e. Angström exponent (AE) and its curvature, in order to infer the fine mode contribution (η) to the total AOD and the size of the fine mode aerosol particles. Perrone et al. (2014) applied this method for the wavelengths widely used in lidar measurements. However, in neither case does the method allow for a direct relationship between η and the fine mode fraction contribution to the total aerosol population. Some discussions are made regarding the effect of shape and composition to the classical AE-ΔAE plot. The potential use of particle backscatter measurements, widely used in aerosol characterization methods together with extinction measurements, is also discussed in the AE-ΔAE grid context. A modification is proposed that yields the submicron contribution to the total volume concentration by using particle extinction data, and a comparison to experimental measurements is made. Our results indicate that the use of a modified AE-ΔAE grid plot to directly obtain submicrometric and micrometric mode fraction to the total aerosol population is feasible if a volume-based bimodal particle size distribution is used instead of a number-based one.Andalusia Regional Government through project P12-RNM-2409Spanish Ministry of Sciences, Innovation and Universities (CGL2016-81092 and CGL2017 -90884 - REDT

Long-range guidance of spinal commissural axons by netrin1 and sonic hedgehog from midline floor plate cells

An important model for axon pathfinding is provided by guidance of embryonic commissural axons from dorsal spinal cord to ventral midline floor plate (FP). FP cells produce a chemoattractive activity, comprised largely of netrin1 (FP-netrin1) and Sonic hedgehog (Shh), that can attract the axons at a distance in vitro. netrin1 is also produced by ventricular zone (VZ) progenitors along the axons’ route (VZ-netrin1). Recent studies using region-specific netrin1 deletion suggested that FP-netrin1 is dispensable and VZ-netrin1 sufficient for netrin guidance activity in vivo. We show that removing FP-netrin1 actually causes guidance defects in spinal cord consistent with long-range action (i.e., over hundreds of micrometers), and double mutant analysis supports that FP-netrin1 and Shh collaborate to attract at long range. We further provide evidence that netrin1 may guide via chemotaxis or haptotaxis. These results support the model that netrin1 signals at both short and long range to guide commissural axons in spinal cord.Z.W. was supported by the Kavli Neural Systems Institute at The Rockefeller University. S.M. was supported by a Keidanren Ishizaka Memorial Foundation fellowship. S.T. was supported by fellowship funds from the Agency for Science, Technology and Research, Singapore (A∗STAR). N.R. was supported by a post-doctoral fellowship from the Shelby White – Leon Levy Foundation. Work performed in the M.T.-L. laboratory was supported by The Rockefeller University and Stanford University, work performed in the A.C. laboratory was supported by a grant from the Agence Nationale de la Recherche (ANR-14-CE13-0004-01), and work performed in the F.C. laboratory was supported by the Canadian Institutes of Health Research (CIHR FDN334023), the Fonds de Recherche du Québec - Santé (FRQS), and the Canada Foundation for Innovation (CFI 33768). F.C. holds the Canada Research Chair in Developmental Neurobiology.Peer reviewe

Characterization of Tajogaite volcanic plumes detected over the Iberian Peninsula from a set of satellite and ground-based remote sensing instrumentation

Three volcanic plumes were detected during the Tajogaite volcano eruptive activity (Canary Islands, Spain, September–December 2021) over the Iberian Peninsula. The spatiotemporal evolution of these events is characterised by combining passive satellite remote sensing and ground-based lidar and sun-photometer systems. The inversion algorithm GRASP is used with a suite of ground-based remote sensing instruments such as lidar/ ceilometer and sun-photometer from eight sites at different locations throughout the Iberian Peninsula. Satellite observations showed that the volcanic ash plumes remained nearby the Canary Islands covering a mean area of 120 ± 202 km2 during the whole period of eruptive activity and that sulphur dioxide plumes reached the Iberian Peninsula

Multiple parallel cell lineages in the developing mammalian cerebral cortex

Cortical neurogenesis follows a simple lineage: apical radial glia cells (RGCs) generate basal progenitors, and these produce neurons. How this occurs in species with expanded germinal zones and a folded cortex, such as human, remains unclear. We used single-cell RNA sequencing from individual cortical germinal zones in ferret and barcoded lineage tracking to determine the molecular diversity of progenitor cells and their lineages. We identified multiple RGC classes that initiate parallel lineages, converging onto a common class of newborn neuron. Parallel RGC classes and transcriptomic trajectories were repeated across germinal zones and conserved in ferret and human, but not in mouse. Neurons followed parallel differentiation trajectories in the gyrus and sulcus, with different expressions of human cortical malformation genes. Progenitor cell lineage multiplicity is conserved in the folded mammalian cerebral cortex.This work was supported by ERC-AdG grant Neurocentro-885382 to M.G. and by Spanish State Research Agency grants SAF2015-69168-R, PGC2018-102172-B, and PDI2021-125618NB and “Severo Ochoa” Programme for Centers of Excellence in R&D (CEX-2021-00165-S) to V.B. Additional support was provided by Spanish State Research Agency FPI contract (BES-2016-077737) to L.D.-V.-A., “JdC incorporación” fellowship (IJC2020-044653-I) to V.F., and by Fundación Tatiana Pérez de Guzmán el Bueno fellowship to A.P.-C.With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX-2021-00165-S).Peer reviewe

Neural stem cells direct axon guidance via their radial fiber scaffold

Neural stem cells directly or indirectly generate all neurons and macroglial cells and guide migrating neurons by using a palisade-like scaffold made of their radial fibers. Here, we describe an unexpected role for the radial fiber scaffold in directing corticospinal and other axons at the junction between the striatum and globus pallidus. The maintenance of this scaffold, and consequently axon pathfinding, is dependent on the expression of an atypical RHO-GTPase, RND3/RHOE, together with its binding partner ARHGAP35/P190A, a RHO GTPase-activating protein, in the radial glia-like neural stem cells within the ventricular zone of the medial ganglionic eminence. This role is independent of RND3 and ARHGAP35 expression in corticospinal neurons, where they regulate dendritic spine formation, axon elongation, and pontine midline crossing in a FEZF2-dependent manner. The prevalence of neural stem cell scaffolds and their expression of RND3 and ARHGAP35 suggests that these observations might be broadly relevant for axon guidance and neural circuit formation.This work was supported by Labex LifeSenses grants ANR-10-LABX-65 and ANR-11-IDEX-0004-02 to A.C.; MINECO SAF2013-49176-C2-1-R and Programa Santander-FUSP to I.P.-R. and J.T.; NIH grants R01 MH115939, NS105640, and NS089662 to A.J.K.; and NIH grants MH103339, MH106934, MH110926, and MH109904 to N.S. Additional support was provided by the Kavli Foundation and the Simons Foundation.Peer reviewe

Associated factors for mortality in a COVID-19 colombian cohort : is the third wave relevant when Mu variant was predominant epidemiologically?

Q1Q1Pacientes con COVID-19Objectives: To evaluate the association between Colombia's third wave when the Mu variant was predominant epidemiologically (until 75%) in Colombia and COVID-19 all-cause in-hospital mortality. Methods: In this retrospective cohort, we included hospitalized patients ≥18 years with SARS-CoV-2 infection between March 2020 to September 2021 in ten hospitals from three cities in Colombia. Description analysis, survival, and multivariate Cox regression analyses were performed to evaluate the association between the third epidemic wave and in-hospital mortality. Results: A total of 25,371 patients were included. The age-stratified time-to-mortality curves showed differences according to epidemic waves in patients ≥75 years (log-rank test p = 0.012). In the multivariate Cox analysis, the third wave was not associated with increased mortality relative to the first wave (aHR 0.95; 95%CI 0.84–1.08), but there was an interaction between age ≥75 years and the third wave finding a lower HR for mortality (aHR 0.56, 95%CI 0.36–0.86). Conclusions: We did not find an increase in in-hospital mortality during the third epidemic wave in which the Mu variant was predominant in Colombia. The reduced hazard in mortality in patients ≥75 years hospitalized in the third wave could be explained by the high coverage of SARS-CoV-2 vaccination in this population and patients with underlying conditions.https://orcid.org/0000-0003-1833-1599https://orcid.org/0000-0001-5363-5729https://orcid.org/0000-0001-6964-2229https://orcid.org/0000-0003-3975-2835https://orcid.org/0000-0001-9441-4375Revista Internacional - IndexadaA1N