Densidad y dimensiones de la fibra de Gmelina arborea en árboles de rápido crecimiento en Costa Rica: relación con el rango de de crecimiento

The objective of this research was to determine growth rate effects measured in tree diameter on wood density parameters (mean, minimum, maximum and intra-ring variation) and in fiber dimensions (wall thickness, fiber width, lumen diameter and fiber length) of trees from fast growth plantations. Thirty mature trees were sampled from thirty different fast-growth plantations with a wide growth rate in Costa Rica. A disc was cut from each tree at DBH. The wood density parameters and fiber dimensions were determined in each growth ring. Some wood density parameters and fiber dimensions were related with growth rate. The minimum and mean density, cell wall thickness, fiber width and lumen diameter decreased with increase in growth rate. Intra-ring wood density variation increased with growth rate but the weak correlation was established. Maximum wood density was not found correlation with growth rate. A pronounced decrease was presented in minimum and mean density from 0 to 20 mm/year and after to 45 mm/year. A pronounced decrease and increase with increase in growth rate were presented in the fiber length and intra-ring wood density, respectively. Lumen diameter and fiber width presented few variations, until 40 mm/year; however, they showed decrease after this growth rate value.La Gmelina arborea es utilizada en plantaciones debido a que las practicas silviculturales producen altas tasas de crecimiento del árbol. El presente trabajo tiene el objetivo de establecer los efectos de la tasa de crecimiento en los parámetros de densidad de la madera (media, máxima, mínima y la variación intra-anillo) y las dimensiones de la fibra (largo, ancho, diámetro del lumen y espesor de pared) en árboles de plantaciones de rápido crecimiento. Fueron seleccionadas treinta árboles de treinta 30 plantaciones diferentes próximas al turno de rotación con una amplia tasa de crecimiento. Un disco a la altura del pecho fue cortado en cada uno de los árboles. Los parámetros de densidad y dimensiones de las fibras fueron determinadas en cada anillo de crecimiento. Algunos de los parámetros de la densidad y las dimensiones de la fibra fueron correlacionados con la tasa de crecimiento. La densidad mínima y el promedio, espesor de pared celular y diámetro del lumen diminuyen con el incremento de la tasa de crecimiento. La variación intra-anillo incremento, pero una débil correlación fue encontrada. La densidad máxima no presentó correlación. Una gran disminución de la densidad mínima y la densidad media fue encontrada cuando la tasa de crecimiento se encuentra entre 0 y 20 mm/año o superior a 45 mm/año. Un pronunciado decrecimiento e incremento con el incremento de la tasa de crecimiento fue encontrado en la longitud de la fibra y la variación intra-anillo, respectivamente. El diámetro del lumen y ancho de la fibra presentaron pocas variaciones cuando la tasa de crecimiento es menor a 40 mm/año, sin embargo, estos mostraron un decrecimiento luego del mencionado valor

Effect of synaptic plasticity on functional connectivity and global activity of a neocortical network model

Work funded by FAPESP-DFG (IRTG 1740/TRP 2011/50151-0) and FAPESP/CEPID/Neuromat (grant 2013/07699-0). ROS is supported by a CAPES MSc scholarship, RFOP is supported by a FAPESP PhD scholarship (grant 2013/25667-8), and ACR is supported by a CNPq research grant (PQ 306251/2014-0

Challenges Using Extrapolated Family-level Macroinvertebrate Metrics in Moderately Disturbed Tropical Streams: a Case-study From Belize

Family-level biotic metrics were originally designed to rapidly assess gross organic pollution effects, but came to be regarded as general measures of stream degradation. Improvements in water quality in developed countries have reignited debate about the limitations of family-level taxonomy to detect subtle change, and is resulting in a shift back towards generic and species-level analysis to assess smaller effects. Although the scale of pollution characterizing past condition of streams in developed countries persists in many developing regions, some areas are still considered to be only moderately disturbed. We sampled streams in Belize to investigate the ability of family-level macroinvertebrate metrics to detect change in stream catchments where less than 30% of forest had been cleared. Where disturbance did not co-vary with natural gradients of change, and in areas characterized by low intensity activities, none of the metrics tested detected significant change, despite evidence of environmental impacts. We highlight the need for further research to clarify the response of metrics to disturbance over a broader study area that allows replication for confounding sources of natural variation. We also recommend research to develop more detailed understanding of the taxonomy and ecology of Neotropical macroinvertebrates to improve the robustness of metric use

BALB/c Mice Infected with Antimony Treatment Refractory Isolate of Leishmania braziliensis Present Severe Lesions due to IL-4 Production

Leishmaniasis is a neglected disease that affects more than 12 million people worldwide. In Brazil, the cutaneous disease is more prevalent with about 28,000 new cases reported each year, and L. braziliensis is the main causative agent. The interesting data about the infection with this parasite is the wide variety of clinical manifestations that ranges from single ulcerated lesions to mucocutaneous and disseminated disease. However, experimental models to study the infection with this parasite are difficult to develop due to high resistance of most mouse strains to the infection, and the mechanisms underlying the distinct manifestations remain poorly understood. Here, the authors use a mouse experimental model of infection with different L. braziliensis isolates, known to induce diseases with distinct severity in the human hosts, to elucidate immune mechanisms that may be involved in the different manifestations. They showed that distinct parasite isolates may modulate host response, and increased IL-4 production and Arg I expression was related to more severe disease, resulting in longer length of disease with larger lesions and reduced parasite clearance. These findings may be useful in the identification of immunological targets to control L. braziliensis infection and potential clinical markers of disease progression

Balancing the immune response in the brain: IL-10 and its regulation

Background: The inflammatory response is critical to fight insults, such as pathogen invasion or tissue damage, but if not resolved often becomes detrimental to the host. A growing body of evidence places non-resolved inflammation at the core of various pathologies, from cancer to neurodegenerative diseases. It is therefore not surprising that the immune system has evolved several regulatory mechanisms to achieve maximum protection in the absence of pathology. Main body: The production of the anti-inflammatory cytokine interleukin (IL)-10 is one of the most important mechanisms evolved by many immune cells to counteract damage driven by excessive inflammation. Innate immune cells of the central nervous system, notably microglia, are no exception and produce IL-10 downstream of pattern recognition receptors activation. However, whereas the molecular mechanisms regulating IL-10 expression by innate and acquired immune cells of the periphery have been extensively addressed, our knowledge on the modulation of IL-10 expression by central nervous cells is much scattered. This review addresses the current understanding on the molecular mechanisms regulating IL-10 expression by innate immune cells of the brain and the implications of IL-10 modulation in neurodegenerative disorders. Conclusion: The regulation of IL-10 production by central nervous cells remains a challenging field. Answering the many remaining outstanding questions will contribute to the design of targeted approaches aiming at controlling deleterious inflammation in the brain.We acknowledge the Portuguese Foundation for Science and Technology (FCT) for providing a PhD grant to DLS (SFRH/BD/88081/2012) and a post-doctoral fellowship to SR (SFRH/BPD/72710/2010). DS, AGC and SR were funded by FEDER through the Competitiveness Factors Operational Programme (COMPETE) and National Funds through FCT under the scope of the project POCI-01-0145-FEDER007038; and by the project NORTE-01-0145-FEDER-000013, supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). The MS lab was financed by Fundo Europeu de Desenvolvimento Regional (FEDER) funds through the COMPETE 2020—Operacional Programme for Competitiveness and Internationalisation (POCI), Portugal 2020, and by Portuguese funds through FCT in the framework of the project “Institute for Research and Innovation in Health Sciences ” (POCI-01-0145-FEDER-007274). MS is a FCT Associate Investigator. The funding body had no role in the design of the study and collection, analysis, and interpretation of the data and in writing the manuscript