Songbird organotypic culture as an in vitro model for interrogating sparse sequencing networks

Sparse sequences of neuronal activity are fundamental features of neural circuit computation; however, the underlying homeostatic mechanisms remain poorly understood. To approach these questions, we have developed a method for cellular-resolution imaging in organotypic cultures of the adult zebra finch brain, including portions of the intact song circuit. These in vitro networks can survive for weeks, and display mature neuron morphologies. Neurons within the organotypic slices exhibit a diversity of spontaneous and pharmacologically induced activity that can be easily monitored using the genetically encoded calcium indicator GCaMP6. In this study, we primarily focus on the classic song sequence generator HVC and the surrounding areas. We describe proof of concept experiments including physiological, optical, and pharmacological manipulation of these exposed networks. This method may allow the cellular rules underlying sparse, stereotyped neural sequencing to be examined with new degrees of experimental control

Tempol-nebivolol therapy potentiates hypotensive effect increasing NO bioavailability and signaling pathway

Nebivolol is a third generation beta blocker with endothelial nitric oxide synthase (eNOS) agonist properties. Considering the role of reactive oxygen species (ROS) in the uncoupling of eNOS, we hypothesized that the preadministration of an antioxidant as tempol, could improve the hypotensive response of nebivolol in normotensive animals increasing the nitric oxide (NO) bioavailability by a reduction of superoxide (O2•−) basal level production in the vascular tissue. Male Sprague Dawley rats were given tap water to drink (control group) or tempol (an antioxidant scavenger of superoxide) for 1 week. After 1 week, Nebivolol, at a dose of 3 mg/kg, was injected intravenously to the control group or to the tempol-treated group. Mean arterial pressure, heart rate, and blood pressure variability were evaluated in the control, tempol, nebivolol, and tempol nebivolol groups, as well as, the effect of different inhibitor as Nβ-nitro-l-arginine methyl ester (L-NAME, a Nitric oxide synthase blocker) or glybenclamide, a KATP channel inhibitor. Also, the expression of α,β soluble guanylate cyclase (sGC), phospho-eNOS, and phospho-vasodilator-stimulated phosphoprotein (P-VASP) were evaluated by Western Blot and cyclic guanosine monophosphate (cGMP) levels by an enzyme-linked immunosorbent assay (ELISA) commercial kit assay. We showed that pretreatment with tempol in normotensive rats produces a hypotensive response after nebivolol administration through an increase in the NO bioavailability and sGC, improving the NO/cGMP/protein kinase G (PKG) pathway compared to that of the nebivolol group. We demonstrated that tempol preadministration beneficiates the response of a third-generation beta blocker with eNOS stimulation properties, decreasing the basal uncoupling of eNOS, and improving NO bioavailability. Our results clearly open a possible new strategy therapeutic for treating hypertension.Fil: Bertera, Facundo Martin. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Farmacología; ArgentinaFil: Santa Cruz, Diego Mario. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Balestrasse, Karina Beatriz. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gorzalczany, Susana Beatriz. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Farmacología. Cátedra de Farmacología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Höcht, Christian. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Farmacología. Cátedra de Farmacología; ArgentinaFil: Taira, Carlos Alberto. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Farmacología. Cátedra de Farmacología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Polizio, Ariel Héctor. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Farmacología. Cátedra de Farmacología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Provenance of the middle Jurassic-Cretaceous sedimentary rocks of the Arequipas basin (South Peru) and implication for the geodynamic evolution of the Central Andes

The southern Peruvian margin is considered a type locality for long-lived, active continental margin and has been the site of almost continuous subduction since at least the Cambrian. Following Triassic rifting, the southern Peruvian margin is supposed to have experimented extensional backarc setting but definitive evidences are scarce. Unlike other margin, the southern Peruvian margin has not been modified by terrane accretion since the onset of subduction and hence the sedimentary rocks of its adjacent basin may have the potential to record the geodynamic history of the margin between the Mitu Triassic rifting episode and the late Cretaceous onset of compression. In this study, we investigate the provenance of middle Jurassic–Santonian sedimentary rocks deposited in the Southern Peruvian Arequipa basin based on the measurement of 42 Sr-Nd isotopic composition, 993 U-Pb zircons ages and 232 Lu-Hf isotopes. The middle Jurassic formation (Puente and Cachios formations) have mean ÎμNd (0) values between from -8.5 (standard deviation (STD): 0.76) and -9.6 (STD:3.05) and are dominated by Brazilian/Pampean (0.5-0.7 Ga) Greenville/Sunsas (0.9–1.3 Ga) zircon U-Pb peak age which suggest an Eastern Cordillera provenance. An eastern provenance is also confirmed by the presence of juvenile to evolved nature of Hf isotopic Permian zircons that may be sourced by the the Eastern Cordillera. The Labra formation is marked by the first appearance of Triassic-Jurassic zircons from the Chocolate formation and by a strong increase in Famatinian zircon contribution but has similar other zircon age population contributions and Æ•Nd(t=0) values to those of the middle Jurassic formations thus suggesting a mixed provenance between Eastern Cordilera and/or Altiplano and Coastal Cordillera sources. The Titonian Gramadal Formation show similar Æ•Nd(t=0) values but distinct U-Pb zircon age pattern with almost similar contribution from all Precambrian sources of the Amazon craton and Eastern Cordillera which suggest a main source located in the Eastern Cordillera or in the Amazon craton. The presence of Jurassic zircons and dominance of Greenville/Sunsas and Brazilian/Pampean zircons population suggest a mixed provenance with sources located both in Coastal and Eastern cordilleras for the Hualhuani formation (Berrasian). Finally, the Santonian Chilcane Formation has the highest Æ•Nd(t=0) value (-5.5) and is characterized by strong contribution of Andean volcanic arc zircon, Jurassic, Permian, and Famatinian zircons which suggest a that these sedimentary rocks are mainly alimented by the Coastal Cordillera. Our multidisciplinary provenance dataset suggests that the middle Jurassic to early Cretaceous sedimentary rocks of the Arequipa basin are predominantly sourced by the Eastern Cordillera and to a lesser extent by the Coastal Cordillera. These associated with recent reevaluation of the depositional setting of the Jurassic to early cretaceous formation and the cumulative proportion curves of zircon age distribution suggest that the Arequipa basin tectonic setting is not that of backarc setting but rather reflect a rift like setting

Fate of Cajal–Retzius Neurons in the Postnatal Mouse Neocortex

Cajal–Retzius (CR) neurons play a critical role in cortical neuronal migration, but their exact fate after the completion of neocortical lamination remains a mystery. Histological evidence has been unable to unequivocally determine whether these cells die or undergo a phenotypic transformation to become resident interneurons of Layer 1 in the adult neocortex. To determine their ultimate fate, we performed chronic in vivo two-photon imaging of identified CR neurons during postnatal development in mice that express the green fluorescent protein (GFP) under the control of the early B-cell factor 2 (Ebf2) promoter. We find that, after birth, virtually all CR neurons in mouse neocortex express Ebf2. Although postnatal CR neurons undergo dramatic morphological transformations, they do not migrate to deeper layers. Instead, their gradual disappearance from the cortex is due to apoptotic death during the second postnatal week. A small fraction of CR neurons present at birth survive into adulthood. We conclude that, in addition to orchestrating cortical layering, a subset of CR neurons must play other roles beyond the third postnatal week

Provenance sedimentary from Arequipa – Tarapacá Basin, based on U-Pb detrital zircons, and Sm-Nd isotopes: implications for southwestern of Gondwana

The beginning of the subduction processes began approximately ~ 530 Ma (Cawood et al., 2005), where an intense magmatism was manifested in the Ordovician that ends at the end of the Devonian (Chew et al., 2007), followed by a process of quiescence magmatic during the Pennsylvanian. The Permico is an assembly of Gondwana where heat accumulation in the Triassic led to a distensive period on a continental scale, which produced the generation of rift processes (i.e. Rift Mitu, Spikings et al., 2016). The closing of the Mitu rift is the reflection of the beginning of an oblique subduction, produced by the subduction of the Farallón oceanic plate under the South American continental plate, this subduction process is known as the beginning of the "Andean Cycle" (Romeuf et al., 1995, Boekhout et al., 2013, Haschke et al., 2006, Ramos & Aleman, 2000, Oliveros et al., 2006). This period is mainly marked by important processes of distention that gave rise to synchronous Mesozoic basins that developed in Western Gondwana. These distension processes were generated by negative roll-back processes (Ramos & Mpodozis., 1989). The Arequipa - Tarapacá basin (Vicente et al., 2006), is an extensive basin developed between 10 ° - 22 ° Lat. South. Where the present work is based on the establishment of sedimentary provenience, for the classic stratotype described by (Jenks, 1945; Vicente et al., 1981) in the valley of the Yura river where approximately ~ 5km of Mesozoic sediments emerge. The present work is based on the presentation of unpublished data of U-Pb in detrital zircons as, Sm-Nd geochemistry in total rock for said sediments. Based on this methodology, we will establish provenance of sediments of the Yura group, as well as the paleogeography of Mesozoic sediments in this portion of the Central Andes

NADPH oxidase 1 as a new regulator of the WNT pathway and the protective effect of vitamin D in colorectal cancer

Trabajo presentado en el 43rd Annual Meeting of the SEBBM, celebrado en Barcelona (España) del 19 al 22 de julio de 2021.Worldwide, colorectal cancer (CRC) is the third most common malignant neoplasm and the second leading cause of cancer-associated mortality, with an estimated increase in global prevalence of 60% by 2030 (1,2). Mutational inactivation of adenomatous polyposis coli (APC) is the hallmark of CRC and leads to an overactivation of WNT signaling that favors the development and progression of CRC (3). Large epidemiological studies suggest that the diabetic population is at increased risk for site-specific cancers, including CRC (4). Our laboratory has shown that hyperglycemia induces the accumulation of ROS in CRC but not healthy cells, driving the activation of a newly described ROS/AMPK/EP300 axis that enhances Wnt/b-catenin signaling. Increased EP300 leads to increased acetylation of β-catenin at K354, a requirement for nuclear accumulation and transcriptional activation of WNT target genes (5,6). The critical role driven by ROS suggest a possible involvement of the NADPH oxidases (NOX family, as a source of ROS. Specifically, NOX 1 and NOX 4 are expressed in colon epithelial cells, and their overexpression in CRC cells promotes cell proliferation and invasiveness (7,8,9,10). Our results indicate that hyperglycemia significantly increases NOX1 levels, in correlation with increased ROS production in CRC cells, suggesting a possible regulation of the ROS/ AMPK/EP300 axis by NOX1. Antioxidant mechanisms dealing with NOX1-induced ROS should be effective against CRC. Vitamin D (1α, 25-dihydroxyvitamin D3) is a powerful antioxidant that inhibits proliferation and promotes differentiation of CRC cells at least partially through inhibition of Wnt/β-catenin signalling. Consequently, vitamin D deficiency is associated with poor survival to CRC (11,12). Our results indicate that vitamin D causes a reduction in the levels and / or activity of some members of the NOX family by turning off the ROS/AMPK/EP300/β-catenin axis and its proliferative and tumorigenic effects. The data suggest a new antitumor mechanism of vitamin D linked to its anti-oxidant action. Our results integrate independent epidemiological links between vitamin D deficiency, diabetes and cancer in one overarching and unifying mechanism

Spatial patterns of summer demersal fish assemblages around the Antarctic Peninsula and South Shetland Islands

During the research programme conducted on the OV Puerto Deseado in the summers of 2011 and 2013, 36 stations were sampled using a demersal net at depths between 53–590 m in the Antarctic Peninsula and South Shetland Islands. A total 3378 fish specimens belonging to 36 species were recorded. Notothenidae was the best-represented family in species number, with Lepidonotothen nudifrons, L. larseni and Trematomus scotti being the most numerous species. Of the fish assemblages, 20% of the species were considered as dominant, 10% as common, 13% as occasional and 57% as rare. Six groups (and two sub-groups) were obtained by the ordination diagram based on geographical location: group 1=Gerlache Strait, group 2=Deception Islands, group 3=Biscoe Island, group 4=between Elephant and King George islands, group 5=northern Antarctic Peninsula, and group 6=South Shetland Islands, with sub-groups 6a shallower South Shetland Islands and 6b deeper South Shetland Islands. Sampling depth and water temperature significantly explained the spatial pattern. A latitudinal pattern of decreasing abundance from north-east to south-west was found in L. larseni and the opposite in T. scotti. The predictability of fish composition in the assemblages’ areas could be a useful tool for ecosystem-based management.Fil: Llompart, Facundo Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional de Tierra del Fuego; ArgentinaFil: Delpiani, Sergio Matias. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Lattuca, María Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Delpiani, Gabriela Elina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Cruz Jiménez, Adriana Milena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Orlando, Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Ceballos, Santiago Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional de Tierra del Fuego; ArgentinaFil: Diaz de Astarloa, Juan Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Vanella, Fabián Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Fernandez, Daniel Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional de Tierra del Fuego; Argentin

Transcriptional portrait of M. bovis BCG during biofilm production shows genes differentially expressed during intercellular aggregation and substrate attachment.

Mycobacterium tuberculosis and M. smegmatis form drug-tolerant biofilms through dedicated genetic programs. In support of a stepwise process regulating biofilm production in mycobacteria, it was shown elsewhere that lsr2 participates in intercellular aggregation, while groEL1 was required for biofilm maturation in M. smegmatis. Here, by means of RNA-Seq, we monitored the early steps of biofilm production in M. bovis BCG, to distinguish intercellular aggregation from attachment to a surface. Genes encoding for the transcriptional regulators dosR and BCG0114 (Rv0081) were significantly regulated and responded differently to intercellular aggregation and surface attachment. Moreover, a M. tuberculosis H37Rv deletion mutant in the Rv3134c-dosS-dosR regulon, formed less biofilm than wild type M. tuberculosis, a phenotype reverted upon reintroduction of this operon into the mutant. Combining RT-qPCR with microbiological assays (colony and surface pellicle morphologies, biofilm quantification, Ziehl-Neelsen staining, growth curve and replication of planktonic cells), we found that BCG0642c affected biofilm production and replication of planktonic BCG, whereas ethR affected only phenotypes linked to planktonic cells despite its downregulation at the intercellular aggregation step. Our results provide evidence for a stage-dependent expression of genes that contribute to biofilm production in slow-growing mycobacteria

GPS deformation rates in the Bajo Segura basin (Eastern Betic Cordillera)

En este trabajo hemos cuantificado las tasas de deformación actual de la cuenca del Bajo Segura (NE del corredor de cizalla de la Bética oriental), a partir del análisis de una red GPS con 11 vértices geodésicos. Se han analizado los datos de cuatro campañas GPS entre junio de 1999 y enero de 2013, que han sido procesados con la versión 6.2 del software GIPSY-OASIS. Este software utiliza la técnica de posicionamiento puntual de precisión conocido por las siglas PPP. Se observa un acortamiento ~N-S en toda la cuenca de mayor magnitud en el sur, en la zona de falla del Bajo Segura, con valores que varían de oeste a este entre 0,73 y 0,24 mm/año. En el borde septentrional de la cuenca, en la zona de falla de Crevillente, los valores de acortamiento N-S son menores. Sin embargo, en esta falla se ha observado un movimiento lateral sinistrorso que, en la componente E-O, varía entre 0,44 y 0,75 mm/año.We estimate the present deformation rates of the Bajo Segura Basin (NE end of the Eastern Betic shear zone), from the analysis of a GPS network with 11 sites. We analyze the data from four observation campaigns carried out between June 1999 and January 2013.We used the 6.2 version of GIPSYOASIS software to process GPS data in Precise Point Positioning mode (PPP). It is observed a ~N-S shortening in the whole basin, higher in the south, along the Bajo Segura fault zone, with rates varying from West to East between 0.73 and 0.24 mm/yr. In the northern border of the basin, along the Crevillente fault zone, N-S deformation rates are lower. However, it is observed a left-lateral movement of this fault zone varying between 0.44 and 0.75 mm/yr in the E-W direction.Este trabajo ha sido financiado por los proyectos del Ministerio de Economía y Competitividad AYA2010-15501 y CGL2011-30153-C02-02 y por el proyecto CSD2006-0041 (European Regional Development Fund-ERDF)

Insights of Active Extension Within a Collisional Orogen From GNSS (Central Betic Cordillera, S Spain)

The coexistence of shortening and extensional tectonic regimes is a common feature in orogenic belts. The westernmost end of the Western Mediterranean is an area undergoing shortening related to the 5 mm/yr NNW‒SSE convergence of the Nubia and Eurasia Plates. In this region, the Central Betic Cordillera shows a regional ENE‒WSW extension. Here, we present GNSS-derived geodetic data along a 170 km-long transect orthogonal to the main active normal faults of the Central Betic Cordillera. Our data indicate that the total extension rate along the Central Betic Cordillera is 2.0 ± 0.3 mm/yr. Extension is accommodated in the eastern (0.8 ± 0.3 mm/yr in the Guadix-Baza Basin) and western (1.3 ± 0.3 mm/yr in the Granada Basin) parts of the Central Betic Cordillera, while no extension is recorded in the central part of the study area. Moreover, our data permit us to quantify, for the first time, short-term fault slip rates of the Granada Fault System, which is one of the main seismogenic sources of the Iberian Peninsula. We deduce a fault slip rate of ∼1.3 ± 0.3 mm/yr for the whole Granada Basin, with 0.9 ± 0.3 mm/yr being accommodated in the Granada Fault System and 0.4 ± 0.3 mm/yr being accommodated in the southwestern sector of the Granada Basin, where no active faults have been previously described at the surface. The heterogeneous extension in the Central Betic Cordillera could be accommodated by shallow high-angle normal faults that merge with a detachment at depth. Part of the active extension could be derived from gravitational instability because of underlying over-thickened crust.This research was funded by the Generalitat Valenciana (Valencian Regional Government, Research project AICO/2021/196), Spanish Ministry of Science, Innovation and University (Research Projects RTI2018-100737-B-I00 and PID2021-127967NB-I00), the University of Alicante (Research Project VIGROB053), the University of Jaén (POAIUJA 2021–2022, CEACTEMA and Programa Operativo FEDER Andalucía, 2014–2020—call made by UJA, 2018, Ref. 1263446), P18-RT-3275 (Junta de Andalucía/FEDER), and the Junta de Andalucía regional government (RNM282 and RNM 148 research groups). The Institut Cartogràfic Valencià, Agencia Valenciana de Seguridad y Respuesta a las Emergencias (Generalitat Valenciana), Consorcio Provincial para el Servicio de Prevención y Extinción de Incendios y Salvamento de Alicante, Excelentísimas Diputaciones Provinciales de Alicante y Castellón, and the Ayuntamiento de Almoradí also provided partial funding