Sulfation degree of glycosaminoglycans triggers distinct cytoskeleton organisation in mesenchymal stem cells

Glycosaminoglycans (GAGs) comprise the closest cellular environment: they are building elements of the ECM and can be also found on cells surface. Their biological activity depends on several parameters among which the negative charge is of prime importance[1]. This charge is generally associated with the presence of sulfate groups (-OSO3H). Sulfation is a dynamic modification: it can occur at various positions within the glycan and different sulfation patterns have been identified for the same organs and cells during their development. However, the mechanisms of coding and transferring information by these functionalities are not yet complete understood, mainly because of (i)the complex physiological microenvironment in which GAGs interactions occur and (ii)the inability to access homogeneous GAGs[2]. In this work, we propose model surfaces bearing GAGs with different sulfation degree as platform to investigate the pathways by which mesenchymal stem cells (MSCs) sense and respond to this peculiar functionality: the -OSO3H. We have selected two natural GAGs for this study: hyaluronic acid (HA) because it is the only non-sulfated glycan and heparin (HEP) as it is the GAG with the highest degree of sulfation. To obtain a larger range of sulfation degrees, we have also prepared a synthetic analogue of HA with a sulfation degree of 1.4 (sHA). All these GAGs were covalently bonded to aminothiols deposited on gold surfaces. MSCs, both from bone marrow and adipose tissue, adhered well to all surfaces. Formation of focal adhesions was observed after only 1h of culture for bone marrow derived MSCs regardless the used substrate. The presence of –OSO3H groups induced different morphology and cytoskeleton organisation: formation of longer filopodia and well pronounced actin fibers were visible for the MSCs from both sources. Moreover, cells were more spread after 24h in contact with – OSO3H containing surfaces. Cells behaved similarly on both sulfated surfaces (sHA and HEP) and differences in cell morphology were less obvious: higher sulfation degree induced less lamellipodia formation while filopodia number and length increased. In summary, the present study provides evidence that sulfation degree of GAGs triggers distinct cytoskeleton organisation in mesenchymal stem cells that may be related with the differentiation of those cells. However, further studies at the molecular level about the exact mechanism of these processes need to be carried out

The elastic wave propagation in rectangular waveguide structure determination of dispersion curves and their application in nondestructive techniques

The use of mechanic waves for assessing structural integrity is a well-known non-destructive technique (NDT). The ultrasound applied in the guided wave in particular requires significant effort in order to understand the complexities of the propagation so as to develop new methods in damage detection, in this case, knowing the interaction between the wave propagation and the geometry of the waveguides is mandatory. In the present work, the wave propagation in rectangular steel rod is presented. In this study, the section dimensions were fixed as 5 × 15 [mm], a typical element of the flexible riser structural amour commonly used in the offshore oil industry. The studies here presented were restricted to [0, 100 KHz] frequencies. This frequency interval is in the range of commercial waveguide equipment commonly applied in ducts in NDT applications. The computation of the dispersion curves is performed by using three different methodologies: (i) analytical solutions, (ii) a method that combines analytical approaches with finite element methods (SAFE), and (iii) experimental method that extracted information from the rod using laser vibrometers and piezoelectric actuators. Finally, two applications based on the dispersion curves determined in the rectangular waveguide are presented to illustrate the possibilities of the curve dispersion knowledge related to the specific geometry in the development and application linked to NDT. The first application consists on showing the possibilities of the techniques that use a fiber grating Bragg cell (FGB) to measure the wave displacement and the second application involves the simulation of pre-fissured prismatic waveguide aimed at searching to induce three characteristic acoustic events. The model was built combining the finite element method and a version of the discrete element method

The elasticwave propagation in rectangular waveguide structure: Determination of dispersion curves and their application in nondestructive techniques

The use of mechanic waves for assessing structural integrity is a well-known non-destructive technique (NDT). The ultrasound applied in the guided wave in particular requires significant effort in order to understand the complexities of the propagation so as to develop new methods in damage detection, in this case, knowing the interaction between the wave propagation and the geometry of the waveguides is mandatory. In the present work, the wave propagation in rectangular steel rod is presented. In this study, the section dimensions were fixed as 5 x 15 [mm], a typical element of the flexible riser structural amour commonly used in the offshore oil industry. The studies here presented were restricted to [0, 100 KHz] frequencies. This frequency interval is in the range of commercial waveguide equipment commonly applied in ducts in NDT applications. The computation of the dispersion curves is performed by using three different methodologies: (i) analytical solutions, (ii) a method that combines analytical approaches with finite element methods (SAFE), and (iii) experimental method that extracted information from the rod using laser vibrometers and piezoelectric actuators. Finally, two applications based on the dispersion curves determined in the rectangular waveguide are presented to illustrate the possibilities of the curve dispersion knowledge related to the specific geometry in the development and application linked toNDT. The first application consists on showing the possibilities of the techniques that use a fiber grating Bragg cell (FGB) to measure the wave displacement and the second application involves the simulation of pre-fissured prismatic waveguide aimed at searching to induce three characteristic acoustic events. The model was built combining the finite element method and a version of the discrete element method

“Você sabe o que é Sexualidade?” - Relato de experiência de oficinas de educação sexual na escola

Este artigo apresenta o relato de experiências de trabalhos de monitorias de acadêmicas de Psicologia e Biomedicina, os quais versavam o oferecimento de oficinas e projeto de sexualidade em duas escolas públicas de São Miguel do Oeste, SC. O objetivo desse trabalho foi verificar o conhecimento de alunos sobre sexualidade e das vivências da sexualidade na adolescência, além de promover discussão e reflexão a respeito de aspectos envolvidos na sexualidade, como o uso de métodos contraceptivos, as DSTs, as relações de gênero, os mitos sexuais e a gravidez na adolescência. Este estudo também buscou investigar a importância da inclusão de trabalhos referentes à sexualidade na escola. Foram empregados como recursos: dinâmica de grupo, jogos didáticos, vídeos educativos e palestras. Os adolescentes participavam das oficinas trazendo exemplos, discutindo e perguntando suas dúvidas. Foi possível perceber ao final desse processo um aumento no nível de informações dos adolescentes participantes, favorecendo, assim, a adoção de práticas de comportamento preventivo e a reflexão e desmistificação da sexualidade.Palavras-chave: Sexualidade. Oficina. Adolescência. Escola. Educação Sexual.

A new method of measuring the cluster peculiar velocity power spectrum

We propose to use spatial correlations of the kinetic Sunyaev-Zeldovich (KSZ) flux as an estimator of the peculiar velocity power spectrum. In contrast with conventional techniques, our new method does not require measurements of the thermal SZ signal or the X-ray temperature. Moreover, this method has the special advantage that the expected systematic errors are always sub-dominant to statistical errors on all scales and redshifts of interest. We show that future large sky coverage KSZ surveys may allow a peculiar velocity power spectrum estimates of an accuracy reaching ~10%.Comment: 5 pages, 2 figures, MNRAS in Press (doi: 10.1111/j.1365-2966.2008.13454.x

Pó-de-basalto no desenvolvimento de plantas de alface e na dinâmica populacional de insetos

The aim of this work was to evaluate effect of the application of basalt powders from three different origins via soil (incorporation) and aerial (spraying) application in the performance of lettuce plants and in the population dynamics of phytophagous insects, respectively. Lettuce seedlings cv. Verônica at 8 days after emergence were transplanted to raised beds after the incorporation of the basalt powders. The effects on plant development were evaluated 50 days after transplantation and the parameters assessed were: plant height, growth of root system, dry mass, insertion diameter, volume of the root system and chlorophyll and carotenoid contents. Insect population dynamics was performed after the application of 100 g of basalt powder diluted in two liters of water (2 L ha) through four sprayings with intervals of 10 days between each. Sampling was performed daily and the insects collected were separated and identified. There was a significant increase in the variables plant height, growth of root system and dry mass in the treatments with the incorporation of basalt powder in the soil when compared to the control treatment. There was also a significant increase of 36% and 20% in the chlorophyll and carotenoid contents in lettuce leaves, respectively. There was no significant difference in the volume of the root system and insertion diameter between the treatments. The aerial spraying on lettuce plants with different basalt powders directly influenced the insect population dynamics with a significant decrease in the number of insects collected in all treatments.O objetivo deste trabalho foi avaliar o efeito da aplicação de pó-de-basalto de três origens diferentes, via aplicação no solo (incorporação) e aérea (pulverização) no desempenho de plantas de alface e na dinâmica populacional de insetos fitófagos, respectivamente. Mudas de alface cv. Verônica com oito dias após a emergência foram transplantadas para canteiros após a incorporação dos pós-de-basalto. Os efeitos no desenvolvimento de plantas foram avaliados 50 dias após o transplante, e os parâmetros avaliados foram: estatura de planta, crescimento do sistema radicular, massa seca, diâmetro da inserção, volume do sistema radicular, teores de clorofila e carotenoides. A dinâmica populacional de insetos foi realizada após a aplicação de 100 g de pó-de-basalto diluídos em dois litros de água, através de quatro pulverizações com intervalos de dez dias entre cada. Amostragens foram realizadas diariamente e os insetos capturados foram triados e identificados. Houve um incremento significativo nas variáveis estaturas de planta, crescimento do sistema radicular e massa seca nos tratamentos onde houve incorporação de pó-debasalto no solo em relação ao tratamento controle. Também foi verificado um aumento significativo de 36 e 20% no teor de clorofila e carotenoides nas folhas de alface, respectivamente. Para o volume e diâmetro da inserção do caule não houve diferença significativa entre os tratamentos. A pulverização aérea em plantas de alface com soluções com pó-de-basalto influenciou diretamente a dinâmica populacional de insetos com uma redução significativa no número de indivíduos amostrados em todos os tratamentos

Human Mas-related G protein-coupled receptors-X1 induce chemokine receptor 2 expression in rat dorsal root ganglia neurons and release of chemokine ligand 2 from the human LAD-2 mast cell line

Primate-specific Mas-related G protein-coupled receptors-X1 (MRGPR-X1) are highly enriched in dorsal root ganglia (DRG) neurons and induce acute pain. Herein, we analyzed effects of MRGPR-X1 on serum response factors (SRF) or nuclear factors of activated T cells (NFAT), which control expression of various markers of chronic pain. Using HEK293, DRG neuron-derived F11 cells and cultured rat DRG neurons recombinantly expressing human MRGPR-X1, we found activation of a SRF reporter gene construct and induction of the early growth response protein-1 via extracellular signal-regulated kinases-1/2 known to play a significant role in the development of inflammatory pain. Furthermore, we observed MRGPR-X1-induced up-regulation of the chemokine receptor 2 (CCR2) via NFAT, which is considered as a key event in the onset of neuropathic pain and, so far, has not yet been described for any endogenous neuropeptide. Up-regulation of CCR2 is often associated with increased release of its endogenous agonist chemokine ligand 2 (CCL2). We also found MRGPR-X1-promoted release of CCL2 in a human connective tissue mast cell line endogenously expressing MRGPR-X1. Thus, we provide first evidence to suggest that MRGPR-X1 induce expression of chronic pain markers in DRG neurons and propose a so far unidentified signaling circuit that enhances chemokine signaling by acting on two distinct yet functionally co-operating cell types. Given the important role of chemokine signaling in pain chronification, we propose that interruption of this signaling circuit might be a promising new strategy to alleviate chemokine-promoted pain

Large-Scale Power Spectrum and Structures From the ENEAR galaxy Peculiar Velocity Catalog

We estimate the mass density fluctuations power spectrum (PS) on large scales by applying a maximum likelihood technique to the peculiarvelocity data of the recently completed redshift-distance survey of early-type galaxies (ENEAR). The general results are in agreement with the high amplitude power spectra found from similar analysis of other independent all-sky catalogs of peculiar velocity data such as MARK III and SFI. For Lambda & Open CDM COBE normalized PS models, the best-fit parameters are confined by a contour approximately defined by Omega h^{1.3}=0.377+-0.08 and Omega h^{0.88}=0.517+-0.083, respectively. Gamma-shape models, free of COBE normalization, resultsin the weak constraint of $\Gamma \geq 0.17$ and in the rather stringent constraint of sigma_8 Omega^{0.6}=1.0+-0.25. All quoted uncertainties refer to 3-sigma confidence-level. The calculated PS is used as a prior for Wiener reconstruction of the density field at different resolutions and the three-dimensional velocity field within a volume of radius ~80 Mpc/h. All major structures in the nearby universe are recovered and are well matched to those predicted from all-sky redshift surveys.Comment: Submitted to MNRAS, 11 Pages, 9 figure

Comprehensive assessment of sequence variation within the copy number variable defensin cluster on 8p23 by target enriched in-depth 454 sequencing

<p>Abstract</p> <p>Background</p> <p>In highly copy number variable (CNV) regions such as the human defensin gene locus, comprehensive assessment of sequence variations is challenging. PCR approaches are practically restricted to tiny fractions, and next-generation sequencing (NGS) approaches of whole individual genomes e.g. by the 1000 Genomes Project is confined by an affordable sequence depth. Combining target enrichment with NGS may represent a feasible approach.</p> <p>Results</p> <p>As a proof of principle, we enriched a ~850 kb section comprising the CNV defensin gene cluster DEFB, the invariable DEFA part and 11 control regions from two genomes by sequence capture and sequenced it by 454 technology. 6,651 differences to the human reference genome were found. Comparison to HapMap genotypes revealed sensitivities and specificities in the range of 94% to 99% for the identification of variations.</p> <p>Using error probabilities for rigorous filtering revealed 2,886 unique single nucleotide variations (SNVs) including 358 putative novel ones. DEFB CN determinations by haplotype ratios were in agreement with alternative methods.</p> <p>Conclusion</p> <p>Although currently labor extensive and having high costs, target enriched NGS provides a powerful tool for the comprehensive assessment of SNVs in highly polymorphic CNV regions of individual genomes. Furthermore, it reveals considerable amounts of putative novel variations and simultaneously allows CN estimation.</p