The influence of nitric oxide on perigeniculate GABAergic cell activity in the anaesthetized cat

[Abstract] We have tested the effect of iontophoretic application of the nitric oxide synthase inhibitor l-nitroarginine on the activity of a population of 53 perigeniculate (PGN) cells, recorded extracellularly in the anaesthetized paralysed cat. In all cells tested with visual stimulation during l-nitroarginine application (n= 15), the visually elicited responses were markedly reduced, on average by 63 ± 15%, and there was a reduction in spontaneous activity too. This effect was blocked by co-application of the substrate for nitric oxide synthase, l-arginine, but not by the inactive d-isoform, although application of l-arginine alone was without effect. Pressure application of the nitric oxide donor S-nitroso-N-acetylpenicillamine (SNAP) elevated both visual responses and spontaneous discharge, an effect also seen with a second nitric oxide donor, sodium nitroprusside (n= 12). The nitric oxide synthase inhibitor l-nitroarginine was applied to a sub-population of seven cells and it selectively decreased NMDA mediated excitation (reduction 80 % 14%) with little or no effect on the excitation mediated by α-amino-3-hydroxy-5-5-methyl-4-isoxazole-propionic acid (AMPA) or quisqualate (effects not statistically significant), and it had no effect (n= 7) on excitation mediated by the metabotropic agonist (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid (ACPD). Furthermore, application of SNAP also increased the magnitude of excitatory responses mediated by NMDA receptors. On a different population of seven cells, application of the new NO donor diethylamine-nitric oxide (DEA-NO) enhanced the actions Of NMDA without an effect on responses to AMPA. These effects are qualitatively and quantitatively similar to those we have previously described for X and Y type cells in the dorsal lateral geniculate nucleus (dLGN), despite the known opposite effects of acetylcholine (ACh) application in the dLGN and PGN (ACh is co-localized with nitric oxide synthase at both sites). We propose that within the PGN nitric oxide acts to enhance transmission utilizing NMDA receptors selectively (thereby interacting with the globally inhibiting effect of ACh at this site) to enhance visual responses, reducing or removing the non-specific inhibitory drive from PGN to dLGN seen in the spindling activity of slow-wave sleep. These effects will act in concert with the facilitatory actions of both ACh and nitric oxide within the dLGN proper, and will thereby enhance the faithful transmission of visual information from retina to cortex.Ministerio de Educación y Ciencia; PB93-034

Radiales time series: 25 years building monitoring and analytical capacities in the Iberian shelf

The RADIALES program has been monitoring shelf waters in Spain for the last 25 years. This is the oldest field program for multidisciplinary marine research addressing long term variability issues at ecosystem level. Core observations include ship-based hydrographic, biogeochemical and plankton observations at monthly frequency in several oceanographic sections along the Iberian shelf. These observations are complemented with buoy and satellite observations and all these data are used to validate hydrographic and ecological models of plankton at local and regional scales. From the first series initiated in the northwestern shelf other programs extended the observations to the Mediterranean and off shelf waters using the same approach. The success of RADIALES extends beyond pure scientific knowledge, as the expertise gathered with the program has been applied to solve multiple environmental issues, from fisheries and pollution to global change. The program is also instrumental for educational purposes, allowing the specialization of students and technicians. Thanks to a basal funding provided by the Instituto Español de Oceanografía, the program currently obtains more than 60% of its annual budget from competitive calls, as it offers an unique platform for coastal research. Among the results of this program are 400 publications, including peer-review papers, 24 Thesis and 54 scientific reports. The RADIALES data are freely distributed to national and international users as a contribution to the development of cost-effective ocean research and marine servicesIEO (RADIALES

Effect of 15 BMI-Associated polymorphisms, reported for europeans, across ethnicities and degrees of amerindian ancestry in mexican children

In Mexico, the genetic mechanisms underlying childhood obesity are poorly known. We evaluated the effect of loci, known to be associated with childhood body mass index (BMI) in Europeans, in Mexican children from different ethnic groups. We performed linear and logistic analyses of BMI and obesity, respectively, in Mestizos and Amerindians (Seris, Yaquis and Nahuatl speakers) from Northern (n = 369) and Central Mexico (n = 8545). We used linear models to understand the effect of degree of Amerindian ancestry (AMA) and genetic risk score (GRS) on BMI z-score. Northern Mexican Mestizos showed the highest overweight-obesity prevalence (47.4%), followed by Seri (36.2%) and Central Mexican (31.5%) children. Eleven loci (SEC16B/rs543874, OLFM4/rs12429545/rs9568856, FTO/rs9939609, MC4R/rs6567160, GNPDA2/rs13130484, FAIM2/rs7132908, FAM120AOS/rs944990, LMX1B/rs3829849, ADAM23/rs13387838, HOXB5/rs9299) were associated with BMI and seven (SEC16B/rs543874, OLFM4/rs12429545/rs9568856, FTO/rs9939609, MC4R/rs6567160, GNPDA2 rs13130484, LMX1B/rs3829849) were associated with obesity in Central Mexican children. One SNP was associated with obesity in Northern Mexicans and Yaquis (SEC16B/rs543874). We found higher BMI z-score at higher GRS (β = 0.11, p = 0.2 × 10−16) and at lower AMA (β = −0.05, p = 6.8 × 10−7). The GRS interacts with AMA to increase BMI (β = 0.03, p = 6.08 × 10−3). High genetic BMI susceptibility increase the risk of higher BMI, including in Amerindian children

Empty Urbanism: the bursting of the Spanish housing bubble

The depth of the Spanish housing crisis manifests itself in the collapse of construction activity and in the amount of housing and land stocks. The geography of the crisis shows its widespread nature, and the intensity of the previous bubble explains spatial differences. Resulting from this collapse are some problematic areas of 'empty urbanism'. An enormous land bubble, emerging from the peculiar Spanish urban development model, was a key factor in the impacts - caused by the crisis - on the territory and land-use plans. The crisis has demonstrated the unsustainability of this and the urgency of change in the existing land-use plans

Multiple late-Pleistocene colonisation events of the Antarctic pearlwort Colobanthus quitensis (Caryophyllaceae) reveal the recent arrival of native Antarctic vascular flora

Aim: Antarctica's remote and extreme terrestrial environments are inhabited by only two species of native vascular plants. We assessed genetic connectivity amongst Antarctic and South American populations of one of these species, Colobanthus quitensis, to determine its origin and age in Antarctica. Location: Maritime Antarctic, sub‐Antarctic islands, South America. Taxon: Antarctic pearlwort Colobanthus quitensis (Caryophyllaceae). Methods: Four chloroplast markers and one nuclear marker were sequenced from 270 samples from a latitudinal transect spanning 21–68° S. Phylogeographic, population genetic and molecular dating analyses were used to assess the demographic history of C. quitensis and the age of the species in Antarctica. Results: Maritime Antarctic populations consisted of two different haplotype clusters, occupying the northern and southern Maritime Antarctic. Molecular dating analyses suggested C. quitensis to be a young (<1 Ma) species, with contemporary population structure derived since the late‐Pleistocene. Main conclusions: The Maritime Antarctic populations likely derived from two independent, late‐Pleistocene dispersal events. Both clusters shared haplotypes with sub‐Antarctic South Georgia, suggesting higher connectivity across the Southern Ocean than previously thought. The overall findings of multiple colonization events by a vascular plant species to Antarctica, and the recent timing of these events, are of significance with respect to future colonizations of the Antarctic Peninsula by vascular plants, particularly with predicted increases in ice‐free land in this area. This study fills a significant gap in our knowledge of the age of the contemporary Antarctic terrestrial biota. Adding to previous inferences on the other Antarctic vascular plant species (the grass Deschampsia antarctica), we suggest that both angiosperm species are likely to have arrived on a recent (late‐Pleistocene) time‐scale. While most major groups of Antarctic terrestrial biota include examples of much longer‐term Antarctic persistence, the vascular flora stands out as the first identified terrestrial group that appears to be of recent origin

Global distribution of two fungal pathogens threatening endangered sea turtles

This work was supported by grants of Ministerio de Ciencia e Innovación, Spain (CGL2009-10032, CGL2012-32934). J.M.S.R was supported by PhD fellowship of the CSIC (JAEPre 0901804). The Natural Environment Research Council and the Biotechnology and Biological Sciences Research Council supported P.V.W. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Thanks Machalilla National Park in Ecuador, Pacuare Nature Reserve in Costa Rica, Foundations Natura 2000 in Cape Verde and Equilibrio Azul in Ecuador, Dr. Jesus Muñoz, Dr. Ian Bell, Dr. Juan Patiño for help and technical support during samplingPeer reviewedPublisher PD

The “Trojan horse” strategy: Seed fungal endophyte symbiosis helps to explain the invasion success of the grass, Poa annua, in Maritime Antarctica

Aim Poa annua L. (annual bluegrass) is presently the sole invasive vascular plant species to have successfully established in Maritime Antarctica, where it poses a significant conservation threat to native plant species. However, the reasons for its success in the region have yet to be established. Here, we determined whether the invasiveness of P. annua, and its competitiveness with the native Antarctic hairgrass Deschampsia antarctica, is influenced by symbioses formed with seed fungal endophytes, and whether plants derived from seeds from four global regions differ in their performance. Locations Four regions (Maritime Antarctica, sub-Antarctica, South America and Europe). Methods Endophyte frequency was measured in P. annua seeds collected from the four regions. The germination, survival, biomass accumulation, flowering and competitiveness with D. antarctica of P. annua plants grown from endophyte-uncolonised and uncolonised seeds was determined in the laboratory. The effects of endophytes on P. annua seed germination and survival and seedling osmoprotection were also assessed in the Maritime Antarctic natural environment using locally-sourced seeds. Results Endophytes were at least twice as frequent in seeds from Maritime Antarctica than in those from other regions. A higher proportion of endophyte-colonized seeds germinated and survived than did uncolonised seeds, but only when they originated from Maritime Antarctica. Seed endophytes increased the competitiveness of P. annua with D. antarctica, but only for plants grown from Maritime Antarctic seeds. In the field, endophyte-colonized seeds from Maritime Antarctica germinated and survived more frequently than uncolonised seeds, and osmoprotection was higher in seedlings grown from colonized seed. Main Conclusions The findings indicate beneficial effects of seed endophytes on invasion-related traits of P. annua, such as survival, germination success and flowering. Together with vegetative and reproductive traits facilitating the colonization process, the seed-fungal endophyte symbiosis can be invoked as an important factor explaining the invasiveness of P. annua in Maritime Antarctica