Geração de mapa de declividades para o Estado do Maranhão como base para Zoneamento Ecológico-Econômico.

O objetivo deste trabalho foi apresentar metodologia empregada na geração de um mapa digital de declividades para o Estado do Maranhão, como base para o Zoneamento Ecológico-Econômico. A base de dados foi gerada a partir de modelo digital de elevação SRTM (Shuttle Radar Topography Mission) com correções realizadas pela FAO (Food and Agriculture Organization). Foi utilizado o Sistema de Informações Geográficas ArcGIS 9.0 para o tratamento do modelo digital e geração das declividades em porcentagem, executando-se posteriormente os processos de filtragem, reclassificação e refinamentos para eliminação de áreas indesejadas. Os resultados mostraram que a metodologia de refinamento permitiu um delineamento eficiente das classes de declividades, denotando um predomínio de terras com baixa declividade. O mapa de declividades juntamente com o mapa pedológico e outras informações apoiarão o zoneamento a ser realizado

Constraint and cost of oxidative stress on reproduction: correlative evidence in laboratory mice and review of the literature.

ABSTRACT: BACKGROUND: One central concept in evolutionary ecology is that current and residual reproductive values are negatively linked by the so-called cost of reproduction. Previous studies examining the nature of this cost suggested a possible involvement of oxidative stress resulting from the imbalance between pro- and anti-oxidant processes. Still, data remain conflictory probably because, although oxidative damage increases during reproduction, high systemic levels of oxidative stress might also constrain parental investment in reproduction. Here, we investigated variation in oxidative balance (i.e. oxidative damage and antioxidant defences) over the course of reproduction by comparing female laboratory mice rearing or not pups. RESULTS: A significant increase in oxidative damage over time was only observed in females caring for offspring, whereas antioxidant defences increased over time regardless of reproductive status. Interestingly, oxidative damage measured prior to reproduction was negatively associated with litter size at birth (constraint), whereas damage measured after reproduction was positively related to litter size at weaning (cost). CONCLUSIONS: Globally, our correlative results and the review of literature describing the links between reproduction and oxidative stress underline the importance of timing/dynamics when studying and interpreting oxidative balance in relation to reproduction. Our study highlights the duality (constraint and cost) of oxidative stress in life-history trade-offs, thus supporting the theory that oxidative stress plays a key role in life-history evolution

Targeting Mitochondrial Protein Expression as a Future Approach for Cancer Therapy

Extensive metabolic remodeling is a fundamental feature of cancer cells. Although early reports attributed such remodeling to a loss of mitochondrial functions, it is now clear that mitochondria play central roles in cancer development and progression, from energy production to synthesis of macromolecules, from redox modulation to regulation of cell death. Biosynthetic pathways are also heavily affected by the metabolic rewiring, with protein synthesis dysregulation at the hearth of cellular transformation. Accumulating evidence in multiple organisms shows that the metabolic functions of mitochondria are tightly connected to protein synthesis, being assembly and activity of respiratory complexes highly dependent on de novo synthesis of their components. In turn, protein synthesis within the organelle is tightly connected with the cytosolic process. This implies an entire network of interactions and fine-tuned regulations that build up a completely under-estimated level of complexity. We are now only preliminarily beginning to reconstitute such regulatory level in human cells, and to perceive its role in diseases. Indeed, disruption or alterations of these connections trigger conditions of proteotoxic and energetic stress that could be potentially exploited for therapeutic purposes. In this review, we summarize the available literature on the coordinated regulation of mitochondrial and cytosolic mRNA translation, and their effects on the integrity of the mitochondrial proteome and functions. Finally, we highlight the potential held by this topic for future research directions and for the development of innovative therapeutic approaches

A greenhouse gas inventory in the municipal landfill of the city of Limeira, Brazil

Landfill main gases are methane and carbon dioxide, and result mainly from the anaerobic digestion of organic waste. The exact distribution of gases in the landfill varies with the landfill age among other factors such as waste composition, moisture, particle size, temperature, pH, age of waste, landfill design and operation. The current Brazilian environmental legislation has encouraged the municipalities to adopt measures to reduce greenhouse gas (GHG) emissions from landfills. The implementation of projects to reduce GHG requires the estimation of the gases produced in the landfill. This research presents a GHG inventory performed in the landfill of the city of Limeira, located in the State of Sao Paulo, Brazil. The inventory was conducted by using the Brazilian GHG Protocol that follows the methodology of the Intergovernmental Panel on Climate Change (IPCC), and also IPCC guidelines. The inventory comprised data from 1985 to 2013; however, data prior to 2000 were estimated, because until that year the landfill was in fact a dump, with no monitoring of the amounts of wastes disposed of. Three categories of emissions were considered: a) direct emissions of CO2 and CH4 from the decomposition of municipal solid waste (MSW) and non-hazardous industrial waste and the emissions produced from waste transportation within the landfill and landfill operation; b) emissions resulting from electricity consumption within the operating limits of the landfill; and, c) indirect emissions from waste transportation throughout the city to the landfill and also from industries to the landfill. The results showed that in the year 2013 were emitted 35,996.91 t of CO2 e into the atmosphere. From the total, 98.91 % of emissions were produced by MSW decomposition; 0.002 % by industrial waste decomposition; 0.332 % by burning fossil fuels during landfill operation; 0.003 % by electricity consumption of electricity in the landfill and 0.75 % by waste transportation.Landfill main gases are methane and carbon dioxide, and result mainly from the anaerobic digestion of organic waste. The exact distribution of gases in the landfill varies with the landfill age among other factors such as waste composition, moisture, part4320832088sem informaçãosem informaçã

A novel mutation in SACS gene in a family from southern Italy

A form of autosomal recessive spastic ataxia (ARSACS) has been described in the Charlevoix and Saguenay regions of Quebec. So far a frameshift and a nonsense mutation have been identified in the SACS gene. The authors report a new mutation (1859insC), leading to a frameshift with a premature termination of the gene product sacsin, in two sisters from consanguineous parents. The phenotype is similar to previously described patients with ARSACS

Mitochondrial uncoupling as a regulator of life-history trajectories in birds: an experimental study in the zebra finch.

Mitochondria have a fundamental role in the transduction of energy from food into ATP. The coupling between food oxidation and ATP production is never perfect, but may nevertheless be of evolutionary significance. The 'uncoupling to survive' hypothesis suggests that 'mild' mitochondrial uncoupling evolved as a protective mechanism against the excessive production of damaging reactive oxygen species (ROS). Because resource allocation and ROS production are thought to shape animal life histories, alternative life-history trajectories might be driven by individual variation in the degree of mitochondrial uncoupling. We tested this hypothesis in a small bird species, the zebra finch (Taeniopygia guttata), by treating adults with the artificial mitochondrial uncoupler 2,4-dinitrophenol (DNP) over a 32-month period. In agreement with our expectations, the uncoupling treatment increased metabolic rate. However, we found no evidence that treated birds enjoyed lower oxidative stress levels or greater survival rates, in contrast to previous results in other taxa. In vitro experiments revealed lower sensitivity of ROS production to DNP in mitochondria isolated from skeletal muscles of zebra finch than mouse. In addition, we found significant reductions in the number of eggs laid and in the inflammatory immune response in treated birds. Altogether, our data suggest that the 'uncoupling to survive' hypothesis may not be applicable for zebra finches, presumably because of lower effects of mitochondrial uncoupling on mitochondrial ROS production in birds than in mammals. Nevertheless, mitochondrial uncoupling appeared to be a potential life-history regulator of traits such as fecundity and immunity at adulthood, even with food supplied ad libitum

Complex phenotype in an Italian family with a novel mutation in SPG3A.

Mutations in the SPG3A gene represent a significant cause of autosomal dominant hereditary spastic paraplegia with early onset and pure phenotype. We describe an Italian family manifesting a complex phenotype, characterized by cerebellar involvement in the proband and amyotrophic lateral sclerosis-like syndrome in her father, in association with a new mutation in SPG3A. Our findings further widen the notion of clinical heterogeneity in SPG3A mutations

Vulnerabilidade à degradação dos solos do município de Campinas, SP.

Este trabalho visou elaborar um mapa de vulnerabilidade à degradação dos solos do Município de Campinas, SP, através de Sistema de Informações Geográficas (SIG), utilizando-se metodologia baseada na ecodinâmica. Para obtenção das classes de vulnerabilidade foram levadas em conta geologia, geomorfologia, pedologia e uso e cobertura das terras, considerando-se cinco classes: estável, moderadamente estável, medianamente estável/vulnerável, moderadamente vulnerável e vulnerável. A classe de vulnerabilidade considerada medianamente estável/vulnerável foi a mais representativa ocupando em 557,9 km2 de extensão, ou seja, ocorre em 70,75% do município. Em seguida a classe moderadamente estável, que ocupa 145,4 km2 de extensão e representa mais de 18% do município. Os resultados obtidos mostram a viabilidade da aplicação do método para a elaboração do mapa de vulnerabilidade ambiental, que pode ser aplicado na gestão territorial de Campinas e demonstra uma susceptibilidade a degradação dos solos.201

Vulnerabilidade à degradação dos solos do município de Campinas, SP.

Este trabalho visou elaborar um mapa de vulnerabilidade à degradação dos solos do Município de Campinas, SP, através de Sistema de Informações Geográficas (SIG), utilizando-se metodologia baseada na ecodinâmica. Para obtenção das classes de vulnerabilidade foram levadas em conta geologia, geomorfologia, pedologia e uso e cobertura das terras, considerando-se cinco classes: estável, moderadamente estável, medianamente estável/vulnerável, moderadamente vulnerável e vulnerável. A classe de vulnerabilidade considerada medianamente estável/vulnerável foi a mais representativa ocupando em 557,9 km2 de extensão, ou seja, ocorre em 70,75% do município. Em seguida a classe moderadamente estável, que ocupa 145,4 km2 de extensão e representa mais de 18% do município. Os resultados obtidos mostram a viabilidade da aplicação do método para a elaboração do mapa de vulnerabilidade ambiental, que pode ser aplicado na gestão territorial de Campinas e demonstra uma susceptibilidade a degradação dos solos

Engineering REST-Specific Synthetic PUF Proteins to Control Neuronal Gene Expression: A Combined Experimental and Computational Study

Regulation of gene transcription is an essential mechanism for differentiation and adaptation of organisms. A key actor in this regulation process is the repressor element 1 (RE1)-silencing transcription factor (REST), a transcriptional repressor that controls more than 2000 putative target genes, most of which are neuron-specific. With the purpose of modulating REST expression, we exploited synthetic, ad hoc designed, RNA binding proteins (RBPs) able to specifically target and dock to REST mRNA. Among the various families of RBPs, we focused on the Pumilio and FBF (PUF) proteins, present in all eukaryotic organisms and controlling a variety of cellular functions. Here, a combined experimental and computational approach was used to design and test 8- and 16-repeat PUF proteins specific for REST mRNA. We explored the conformational properties and atomic features of the PUF-RNA recognition code by Molecular Dynamics simulations. Biochemical assays revealed that the 8- and 16-repeat PUF-based variants specifically bind the endogenous REST mRNA without affecting its translational regulation. The data also indicate a key role of stacking residues in determining the binding specificity. The newly characterized REST-specific PUF-based constructs act as excellent RNA-binding modules and represent a versatile and functional platform to specifically target REST mRNA and modulate its endogenous expression