Fluctuating position-related cognitive disturbances and recurrent cerebral ischemic attacks as presenting symptoms in a patient with platypnea-orthodeoxya syndrome

Platypnea-orthodeoxia syndrome is a condition of dyspnea and hypoxia whilst in the upright position, which improves in the recumbent position. We present a case of platypnea-orthodeoxia due to a fenestrated atrial septal aneurysm that induced recurrent strokes and a recent condition of fluctuating confusion and cognitive impairment, modified by position, associated with rapid variations of O2 saturation position related. The suspect of platypnea-orthodeoxia syndrome may be hypothesized in case of patients with recurrent cerebral ischemia and fluctuating cognitive disturbances induced by change of position. In those cases a careful echocardiographic evaluation and O2 saturation determination in up and downright position are required

La ictiofauna como bioindicadora de la cuenca del Aº Langueyú

Objetivos: Evaluar la calidad ambiental de la cuenca del arroyo Langueyú y analizar su relación con la estructura y composición de la comunidad de peces, para poder inferir a partir de los peces la condición ambiental, y utilizar esta información como una herramienta de diagnóstico ambiental de este sistema fluvial.Área: Ciencias Biológicas, Ambiente y Salud

Regulations concerning agriculture and air pollution

The main issues related to the atmospheric pollution are the stratospheric ozone depletion, the transboundary air pollution, the troposphere air quality and the climate change. The three last decades have seen the birth of several measures for the atmosphere safeguard. Agricultural activities play a key role in determining, preventing and mitigating atmospheric pollution. The emission to atmosphere of different ozone-depleting substances is regulated by the Montreal Protocol. The role of agriculture activity in ozone depletion is linked to the utilization of methyl bromide as soil sterilant and to the emission of nitrogen oxides and nitrous oxide, from agricultural soils. The Convention on long-range transboundary air pollution regulates the emission of several pollutants, i.e. sulphur dioxide, nitrogen oxides, ammonia, non methane volatile organic compounds, carbon monoxide, heavy metals, persistent organic pollutants, and tropospheric ozone. The agriculture sector is responsible for a large part of the emissions of ammonia and nitrogen oxides, mainly through manure management and nitrogen fertilization, and of most persistent organic pollutants, largely used in the past as insecticides and fungicides. The increase of the greenhouse gases (GHGs) concentration in the atmosphere is under the control of the Kyoto Protocol. Agriculture accounts for 59-63% of global non-CO2 GHGs emissions but at the same time it contributes to the atmospheric CO2 concentration stabilisation through the substitution of fossil fuels by biofuels and the sequestration of C in soil and vegetal biomass. In this paper we provide an outline of the numerous scientific and legislative initiatives aimed at protecting the atmosphere, and we analyse in detail the agriculture sector in order to highlight both its contribution to atmospheric pollution and the actions aimed at preventing and mitigating it

Agronomic benefits and detriments of using biochar

The use of biochar, a secondary product of pyrolysis after syngas and bio-oil production for bioenergy, is promoted for agricultural purposes. Its potential for C sequestration and greenhouse gas emission reduction can help for mitigating climate change and potential adverse impacts to ecosystems. Additionally, it represents an alternative means for containing water and atmospheric pollution ascribed to large volumes of crop and animal wastes. As a soil amendment, biochar has received increased interest due to its role in enhancing nutrient- and water-use efficiencies. Please click on the file below for full content of the abstract

Crop response to soils amended with biochar: Expected benefits and unintended risks

Biochar (BC) from biomass waste pyrolysis has been widely studied due to its ability to increase carbon sequestration, reduce greenhouse gas emissions, and enhance both crop growth and soil quality. This review summarises the current knowledge of BC production, characterisation, and types, with a focus on its positive effects on crop yield and soil properties vs the unintended risks associated with these effects. Biochar-amended soils enhance crop growth and yield via several mechanisms: expanded plant nutrient and water availability through increased use efficiencies, improved soil quality, and suppression of soil and plant diseases. Yield response to BC has been shown to be more evident in acidic and sandy soils than in alkaline and fine-textured soils. Biochar composition and properties vary considerably with feedstock and pyrolysis conditions so much that its concentrations of toxic compounds and heavy metals can negatively impact crop and soil health. Consequently, more small-scale and greenhouse-sited studies are in process to investigate the role of BC/soil/crop types on crop growth, and the mechanisms by which they influence crop yield. Similarly, a need exists for long-term, field-scale studies on the effects (beneficial and harmful) of BC amendment on soil health and crop yields, so that production guidelines and quality standards may be developed for BCs derived from a range of feedstocks

ROLE OF NUCLEAR ENVELOPE PROTEIN MAN1 IN NUCLEAR ORGANISATION AND MAINTENANCE OF GENOME STABILITY

The eukaryotic cell nucleus is characterized by a defined spatial organization of the chromatin, which relies on the physical tethering of many genomic loci to the inner surface of the nuclear envelope. This interaction is mainly mediated by lamins and lamin-associated proteins, which create a protein network at the nuclear periphery called nuclear lamina. Man1 is a member of a lamin-associated protein family known as LEM-domain proteins, which are characterized by the presence of a highly conserved domain, called LEM, that mediates the interaction with the chromatin. Data obtained with the yeast Man1 homolog Src1 underline the importance of this protein in different processes of the cell cycle, such as chromosome segregation, nuclear pores assembly, gene expression, chromatin organization and maintenance of genome stability, while in animal models, the function of Man1 has been associated to the regulation of developmental signalling pathways during embryogenesis. In this study, truncated recombinant mutants of Man1, containing the LEM domain, were shown to inhibit nuclear assembly and alter nuclear pore formation when added to Xenopus laevis cell-free extracts. Moreover, Xenopus nuclei assembled in the presence of Man1 truncated fragments were characterized by defects in chromatin organization, DNA replication and accumulation of DNA damage and, as a consequence, they failed to progress through mitosis. Furthermore, mouse embryonic stem cells (mESCs) depleted for Man1 showed evident signs of spontaneous differentiation, indicating inability in the maintenance of stem cell features. Intriguingly, preliminary analysis of Man1-knockout mESCs transcriptional profile showed an alteration of gene expression at the level of pericentromeric and telomeric regions, underlining a potential link between Man1 and genomic stability of these particular regions. In conclusion, this study illustrates the importance of Man1 in ensuring the proper chromatin organization necessary to support different cellular and DNA metabolic processes

Fish assemblage structure in a Neotropical urbanised prairie stream exposed to multiple natural and anthropic factors

A myriad of factors affect stream fish assemblages, and most of them are intimately regulated by surrounding land uses. One of the most pernicious impacts on streams is the release of urban effluents. Accordingly, understanding the fish assemblage patterns as well as the environmental drivers that modulate them in the context of urban streams which also are exposed to other land uses is mandatory. We evaluated the longitudinal patterns of fish assemblages in an urbanised Neotropical prairie stream exposed to downstream patches of different surrounding land uses. Several variables of water quality, in-stream habitat and riparian corridors were measured, and their relationships with fish metrics were explored. A fish metric selection protocol was implemented, and several multivariate analyses were used. Three main patterns of fish response were observed. Assemblage-level attributes as diversity, richness, biomass, number of families and trophic guilds and proportion of Characiformes and intolerant species were responsive to the natural gradient in habitat (pools) and riparian (riparian width) conditions expected in non-impacted lotic ecosystems. Conversely, a downstream continuum of recovery in water quality (dissolved oxygen, conductivity, NO3:NH4 and bacteriological loads) and habitat structure (sediment depth) would influence the distribution of fish species regarding their environmental tolerance and habitat preferences. Finally, local habitat aspects (nitrites, submerged macrophytes, bare soil cover and bank incisions by livestock) seemed relevant for the trophic structure (omnivorous species) of fish assemblages. A complex natural and anthropic longitudinal scenario together with local disruptions imposed by surrounding land uses were directive for fish.Fil: Bertora, Andrea. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto Multidisciplinario de Ecosistemas y Desarrollo Sustentable; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Grosman, Manuel Fabián. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto Multidisciplinario de Ecosistemas y Desarrollo Sustentable; ArgentinaFil: Sanzano, Pablo Miguel. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto Multidisciplinario de Ecosistemas y Desarrollo Sustentable; ArgentinaFil: Rosso, Juan Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentin

Combined effects of urbanization and longitudinal disruptions in riparian and in-stream habitat on water quality of a prairie stream

Local habitat and riparian modifications imposed by surrounding land use drastically impact the water quality of streams. However, whether these effects could still be discernible when the watercourse also receives urbanization effluents has not been fully explored. We evaluated the water quality of a Neotropical prairie stream exposed to urbanization and explored the role of downstream patches of different surrounding land uses (cropland and livestock) in further regulating water quality. Forty-two variables of water quality, habitat structure and riparian condition were measured at four reaches of the Langueyú stream. Significant differences in water quality were observed. Water conductivity, dissolved oxygen, salinity, dissolved solids, chloride, inorganic nitrogen and bacteriological loads displayed a continuum of recovery from the urban reach. Indeed, almost 24 percent of the total variation in water quality was explained by the longitudinal arrangement of sites. Alternatively, pH, phosphorous, suspended solids and chemical oxygen demand showed a disruption in this continuum of recovery and were highly related with local aspects of habitat structure and riparian conditions imposed by cropland and livestock. Key aspects of effluent treatment, riparian integrity and in-stream habitat must be addressed within a comprehensive social context in order to design sustainable management of fluvial urbanised ecosystems.Fil: Bertora, Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto Multidisciplinario de Ecosistemas y Desarrollo Sustentable; ArgentinaFil: Grosman, Manuel Fabián. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto Multidisciplinario de Ecosistemas y Desarrollo Sustentable; ArgentinaFil: Sanzano, Pablo Miguel. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto Multidisciplinario de Ecosistemas y Desarrollo Sustentable; ArgentinaFil: Rosso, Juan Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentin