108 research outputs found

    TSUNAMI HAZARD IN NORTHERN VENEZUELA

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    Based on LANDSAT ETM and Digital Elevation Model (DEM) data derived by the Shuttle Radar Topography Mission (SRTM, 2000) of the coastal areas of Northern Venezuela were investigated in order to detect traces of earlier tsunami events. Digital image processing methods used to enhance LANDSAT ETM imageries and to produce morphometric maps (such as hillshade, slope, minimum and maximum curvature maps) based on the SRTM DEM data contribute to the detection of morphologic traces that might be related to catastrophic tsunami events. These maps combined with various geodata such as seismotectonic data in a GIS environment allow the delineation of coastal regions with potential tsunami risk. The LANDSAT ETM imageries merged with digitally processed and enhanced SRTM data clearly indicate areas that might be prone by flooding in case of catastrophic tsunami events

    The fibrinogen γA/γ′ isoform does not promote acute arterial thrombosis in mice

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    Elevated plasma fibrinogen associates with arterial thrombosis in humans and promotes thrombosis in mice by increasing fibrin formation and thrombus fibrin content. Fibrinogen is composed of six polypeptide chains: (Aα, Bβ, and γ)2. Alternative splicing of the γ chain leads to a dominant form (γA/γA) and a minor species (γA/γ’). Epidemiologic studies have detected elevated γA/γ’ fibrinogen in patients with arterial thrombosis, suggesting this isoform promotes thrombosis. However, in vitro data show that γA/γ’ is anticoagulant due to its ability to sequester thrombin, and suggest its expression is upregulated in response to inflammatory processes

    HY5 and phytochrome activity modulate shoot to root coordination during thermomorphogenesis.

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    This is the author accepted manuscript. The final version is available from The Company of Biologists via the DOI in this record Temperature is one of the most impactful environmental factors to which plants adjust their growth and development. While the regulation of temperature signaling has been extensively investigated for the aerial part of plants, much less is known and understood about how roots sense and modulate their growth in response to fluctuating temperatures. Here we found that shoot and root growth responses to high ambient temperature are coordinated during early seedling development. A shoot signaling module that includes HY5, the phytochromes and the PIFs exerts a central function in coupling these growth responses and maintain auxin levels in the root. In addition to the HY5/PIF-dependent shoot module, a regulatory axis composed of auxin biosynthesis and auxin perception factors controls root responses to high ambient temperature. Together, our findings show that shoot and root developmental responses to temperature are tightly coupled during thermomorphogenesis and suggest that roots integrate energy signals with local hormonal inputs.National Institute of General Medical Sciences of the National Institutes of Healt

    Quantification of the level descriptors for the standard EQ-5D three-level system and a five-level version according to two methods

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    Objectives: Our aim was to compare the quantitative position of the level descriptors of the standard EQ-5D three-level system (3L) and a newly developed, experimental five-level version (5L) using a direct and a vignette-based indirect method. Methods: Eighty-two respondents took part in the study. The direct method represented a visual analog scale (VAS) rating of the nonextreme level descriptors for each dimension and each instrument separately. The indirect method required respondents to score 15 health scenarios with 3L, 5L and a VAS scale. Investigated were: (1) equidistance (Are 3L and 5L level descriptors distributed evenly over the VAS continuum?); (2) isoformity (Do the identical level descriptors on 3L and 5L yield similar results?); and (3) consistency between dimensions (Do the positions of similar level descriptors differ across dimensions within instruments?). Results: Equidistance without transformation was rejected for all dimensions for both 3L and 5L but satisfied for 5L after transformation. Isoformity gave mixed results. Consistency between dimensions was satisfied for both instruments and both methods. Discussion: The level descriptors have similar distributions across comparable dimensions within each system, but the pattern differs between 3L and 5L. This methodological study provides evidence of increased descriptive power and a broadened measurement continuum that encourages the further development of an official five-level EQ-5D

    Fibrinogen beta variants confer protection against coronary artery disease in a Greek case-control study

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    <p>Abstract</p> <p>Background</p> <p>Although plasma fibrinogen levels are related to cardiovascular risk, data regarding the role of fibrinogen genetic variation in myocardial infarction (MI) or coronary artery disease (CAD) etiology remain inconsistent. The purpose of the present study was to investigate the effect of <it>fibrinogen A (FGA)</it>, <it>fibrinogen B (FGB) </it>and <it>fibrinogen G (FGG) </it>gene SNPs and haplotypes on susceptibility to CAD in a homogeneous Greek population.</p> <p>Methods</p> <p>We genotyped for rs2070022, rs2070016, rs2070006 in <it>FGA </it>gene, the rs7673587, rs1800789, rs1800790, rs1800788, rs1800787, rs4681 and rs4220 in <it>FGB </it>gene and for the rs1118823, rs1800792 and rs2066865 SNPs in <it>FGG </it>gene applying an arrayed primer extension-based genotyping method (APEX-2) in a sample of CAD patients (n = 305) and controls (n = 305). Logistic regression analysis was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs), before and after adjustment for potential confounders.</p> <p>Results</p> <p>None of the <it>FGA </it>and <it>FGG </it>SNPs and <it>FGA, FGB, FGG </it>and <it>FGA-FGG </it>haplotypes was associated with disease occurrence after adjustment. Nevertheless, rs1800787 and rs1800789 SNPs in <it>FGB </it>gene seem to decrease the risk of CAD, even after adjustment for potential confounders (OR = 0.42, 95%CI: 0.19-0.90, p = 0.026 and OR = 0.44, 95%CI:0.21-0.94, p = 0.039, respectively).</p> <p>Conclusions</p> <p><it>FGA </it>and <it>FGG </it>SNPs as well as <it>FGA, FGB, FGG </it>and <it>FGA-FGG </it>haplotypes do not seem to be important contributors to CAD occurrence in our sample. On the contrary, <it>FGB </it>rs1800787 and rs1800789 SNPs seem to confer protection to disease onset lowering the risk by about 50% in homozygotes for the minor alleles.</p

    A Genome-Wide Association Study of the Protein C Anticoagulant Pathway

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    The Protein C anticoagulant pathway regulates blood coagulation by preventing the inadequate formation of thrombi. It has two main plasma components: protein C and protein S. Individuals with protein C or protein S deficiency present a dramatically increased incidence of thromboembolic disorders. Here, we present the results of a genome-wide association study (GWAS) for protein C and protein S plasma levels in a set of extended pedigrees from the Genetic Analysis of Idiopathic Thrombophilia (GAIT) Project. A total number of 397 individuals from 21 families were typed for 307,984 SNPs using the Infinium® 317 k Beadchip (Illumina). Protein C and protein S (free, functional and total) plasma levels were determined with biochemical assays for all participants. Association with phenotypes was investigated through variance component analysis. After correcting for multiple testing, two SNPs for protein C plasma levels (rs867186 and rs8119351) and another two for free protein S plasma levels (rs1413885 and rs1570868) remained significant on a genome-wide level, located in and around the PROCR and the DNAJC6 genomic regions respectively. No SNPs were significantly associated with functional or total protein S plasma levels, although rs1413885 from DNAJC6 showed suggestive association with the functional protein S phenotype, possibly indicating that this locus plays an important role in protein S metabolism. Our results provide evidence that PROCR and DNAJC6 might play a role in protein C and free protein S plasma levels in the population studied, warranting further investigation on the role of these loci in the etiology of venous thromboembolism and other thrombotic diseases

    Gibberellin Acts through Jasmonate to Control the Expression of MYB21, MYB24, and MYB57 to Promote Stamen Filament Growth in Arabidopsis

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    Precise coordination between stamen and pistil development is essential to make a fertile flower. Mutations impairing stamen filament elongation, pollen maturation, or anther dehiscence will cause male sterility. Deficiency in plant hormone gibberellin (GA) causes male sterility due to accumulation of DELLA proteins, and GA triggers DELLA degradation to promote stamen development. Deficiency in plant hormone jasmonate (JA) also causes male sterility. However, little is known about the relationship between GA and JA in controlling stamen development. Here, we show that MYB21, MYB24, and MYB57 are GA-dependent stamen-enriched genes. Loss-of-function of two DELLAs RGA and RGL2 restores the expression of these three MYB genes together with restoration of stamen filament growth in GA-deficient plants. Genetic analysis showed that the myb21-t1 myb24-t1 myb57-t1 triple mutant confers a short stamen phenotype leading to male sterility. Further genetic and molecular studies demonstrate that GA suppresses DELLAs to mobilize the expression of the key JA biosynthesis gene DAD1, and this is consistent with the observation that the JA content in the young flower buds of the GA-deficient quadruple mutant ga1-3 gai-t6 rga-t2 rgl1-1 is much lower than that in the WT. We conclude that GA promotes JA biosynthesis to control the expression of MYB21, MYB24, and MYB57. Therefore, we have established a hierarchical relationship between GA and JA in that modulation of JA pathway by GA is one of the prerequisites for GA to regulate the normal stamen development in Arabidopsis

    Rice early flowering1, a CKI, phosphorylates DELLA protein SLR1 to negatively regulate gibberellin signalling

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    The plant hormone gibberellin (GA) is crucial for multiple aspects of plant growth and development. To study the relevant regulatory mechanisms, we isolated a rice mutant earlier flowering1, el1, which is deficient in a casein kinase I that has critical roles in both plants and animals. el1 had an enhanced GA response, consistent with the suppression of EL1 expression by exogenous GA3. Biochemical characterization showed that EL1 specifically phosphorylates the rice DELLA protein SLR1, proving a direct evidence for SLR1 phosphorylation. Overexpression of SLR1 in wild-type plants caused a severe dwarf phenotype, which was significantly suppressed by EL1 deficiency, indicating the negative effect of SLR1 on GA signalling requires the EL1 function. Further studies showed that the phosphorylation of SLR1 is important for maintaining its activity and stability, and mutation of the candidate phosphorylation site of SLR1 results in the altered GA signalling. This study shows EL1 a novel and key regulator of the GA response and provided important clues on casein kinase I activities in GA signalling and plant development

    Analytical methods for inferring functional effects of single base pair substitutions in human cancers

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    Cancer is a genetic disease that results from a variety of genomic alterations. Identification of some of these causal genetic events has enabled the development of targeted therapeutics and spurred efforts to discover the key genes that drive cancer formation. Rapidly improving sequencing and genotyping technology continues to generate increasingly large datasets that require analytical methods to identify functional alterations that deserve additional investigation. This review examines statistical and computational approaches for the identification of functional changes among sets of single-nucleotide substitutions. Frequency-based methods identify the most highly mutated genes in large-scale cancer sequencing efforts while bioinformatics approaches are effective for independent evaluation of both non-synonymous mutations and polymorphisms. We also review current knowledge and tools that can be utilized for analysis of alterations in non-protein-coding genomic sequence

    The transcriptional regulator BBX24 impairs DELLA activity to promote shade avoidance in Arabidopsis thaliana

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    [EN] In response to canopy shade, plant vegetative structures elongate to gain access to light. However, the mechanism that allows a plastic transcriptional response to canopy shade light is not fully elucidated. Here we propose that the activity of PIF4, a key transcription factor in the shade signalling network, is modulated by the interplay between the BBX24 transcriptional regulator and DELLA proteins, which are negative regulators of the gibberellin (GA) signalling pathway. We show that GA-related targets are enriched among genes responsive to BBX24 under shade and that the shade-response defect in bbx24 mutants is rescued by a GA treatment that promotes DELLA degradation. BBX24 physically interacts with DELLA proteins and alleviates DELLA-mediated repression of PIF4 activity. The proposed molecular mechanism provides reversible regulation of the activity of a key transcription factor that may prove especially relevant under fluctuating light conditions.We thank Santiago Mora Garcia for valuable initial discussions and Peter Quail for the PIL1::LUC construct. This work was supported by grants from Agencia Nacional de Promocion Cientifica y Tecnologica, and Universidad de Buenos Aires (to J.F.B), and the Spanish Ministry of Science, BIO2010-15071 (to M.A.B.).Crocco, C.; Locascio ., AAM.; Escudero, CM.; Alabadí Diego, D.; Blazquez Rodriguez, MA.; Botto, J. (2015). The transcriptional regulator BBX24 impairs DELLA activity to promote shade avoidance in Arabidopsis thaliana. Nature Communications. 6:1-10. https://doi.org/10.1038/ncomms7202S1106Valladares, F. & Niinemets, U. Shade tolerance, a key plant feature of complex nature and consequences. Annu. Rev. Ecol. Evol. Syst. 39, 237–257 (2008).Casal, J. J. Photoreceptor signaling networks in plant responses to shade. Annu. Rev. Plant Biol. 64, 403–427 (2013).Botto, J. F. & Coluccio, M. P. Seasonal and plant-density dependency for quantitative trait loci affecting flowering time in multiple populations of Arabidopsis thaliana. Plant Cell Environ. 30, 1465–1479 (2007).Coluccio, M. P., Sánchez, S., Kasulin, L., Yanovsky, M. J. & Botto, J. F. Genetic mapping of natural variation in a shade avoidance response: ELF3 is the candidate gene for a QTL in hypocotyl growth regulation. J. Exp. Bot. 62, 167–176 (2011).Filiault, D. L. & Maloof, J. N. A genome-wide association study identifies variants underlying the Arabidopsis thaliana shade avoidance response. PLoS. Genet. 8, e1002589 (2012).Kasulin, L., Agrofoglio, Y. & Botto, J. F. The receptor-like kinase ERECTA contributes to the shade-avoidance syndrome in a background-dependent manner. Ann. Bot. 111, 811–819 (2013).Leivar, P. & Monte, E. PIFs: systems integrators in plant development. Plant Cell 26, 56–78 (2014).Lorrain, S., Allen, T., Duek, P. D., Whitelam, G. C. & Fankhauser, C. Phytochrome-mediated inhibition of shade avoidance involves degradation of growth-promoting bHLH transcription factors. Plant J. 53, 312–323 (2008).Hornitschek, P., Lorrain, S., Zoete, V., Michielin, O. & Fankhauser, C. Inhibition of the shade avoidance response by formation of non-DNA binding bHLH heterodimers. EMBO J. 28, 3893–3902 (2009).Gangappa, S. N. & Botto, J. F. The BBX family of plant transcription factors. Trends Plant Sci. 19, 460–470 (2014).Crocco, C. D., Holm, M., Yanovsky, M. J. & Botto, J. F. AtBBX21 and COP1 genetically interact in the regulation of shade avoidance. Plant J. 64, 551–562 (2010).Gangappa, S. N. et al. The Arabidopsis B-BOX protein BBX25 interacts with HY5, negatively regulating BBX22 expression to suppress seedling photomorphogenesis. Plant Cell 25, 1243–1257 (2013).Devlin, F. P., Yanovsky, M. J. & Kay, S. A. A genomic analysis of the shade avoidance response in Arabidopsis. Plant Physiol. 133, 1–13 (2003).Hisamatsu, T., King, R. W., Helliwell, C. A. & Koshioka, M. The involvement of gibberellin 20-oxidase genes in phytochrome-regulated petiole elongation of Arabidopsis. Plant Physiol. 138, 1106–1116 (2005).Locascio, A., Blázquez, M. A. & Alabadí, D. Genomic analysis of DELLA protein activity. Plant Cell Physiol. 54, 1229–1237 (2013).de Lucas, M. et al. A molecular framework for light and gibberellin control of cell elongation. Nature 451, 480–486 (2008).Feng, S. et al. Coordinated regulation of Arabidopsis thaliana development by light and gibberellins. Nature 451, 475–480 (2008).Djakovic-Petrovic, T., de Wit, M., Voesenek, L. A. C. J. & Pierik, R. DELLA protein function in growth responses to canopy signals. Plant J. 51, 117–126 (2007).Pierik, R., de Wit, M. & Voesenek, L. A. C. J. Growth-mediated stress escape: convergence of signal transduction pathways activated upon exposure to two different environmental stresses. New Phytol. 189, 122–134 (2011).Colebrook, E. H., Thomas, S. G., Phillips, A. L. & Hedden, P. The role of gibberellin signalling in plant responses to abiotic stress. J. Exp. Biol. 217, 67–75 (2014).Holtan, H. E. et al. BBX32, an Arabidopsis B-Box protein, functions in light signaling by suppressing HY5-regulated gene expression and interacting with STH2/BBX21. Plant Physiol. 156, 2109–2123 (2011).Xu, D. et al. Convergence of light and ABA signaling on the ABI5 promoter. PLoS. Genet. 10, e1004197 (2014).Pierik, R., Djakovic-Petrovic, T., Keuskamp, D. H., de Wit, M. & Voesenek, L. A. C. J. Auxin and ethylene regulate elongation responses to neighbor proximity signals independent of gibberellin and DELLA proteins in Arabidopsis. Plant Physiol. 149, 1701–1712 (2009).Keuskamp, D. H. et al. Blue-light-mediated shade avoidance requires combined auxin and brassinosteroid action in Arabidopsis seedlings. Plant J. 67, 208–217 (2011).Li, L. et al. Linking photoreceptor excitation to changes in plant architecture. Genes Dev. 26, 785–790 (2012).Hornitschek, P. et al. Phytochrome interacting factors 4 and 5 control seedling growth in changing light conditions by directly controlling auxin signaling. Plant J. 71, 699–711 (2012).Leivar, P. et al. Dynamic antagonism between phytochromes and PIF family basic helix-loop-helix factors induces selective reciprocal responses to light and shade in a rapidly responsive transcriptional network in Arabidopsis. Plant Cell 24, 1398–1419 (2012).Oh, E., Zhu, J.-Y. & Wang, Z.-Y. Interaction between BZR1 and PIF4 integrates brassinosteroid and environmental responses. Nat. Cell Biol. 14, 802–809 (2012).Dill, A. & Sun, T. P. Synergistic derepression of gibberellin signaling by removing RGA and GAI function in Arabidopsis thaliana. Genetics 159, 777–785 (2001).Cole, B., Kay, S. A. & Chory, J. Automated analysis of hypocotyl growth dynamics during shade avoidance in Arabidopsis. Plant J. 65, 991–1000 (2011).Zhang, Y. et al. A quartet of PIF bHLH factors provides a transcriptionally centered signaling hub that regulates seedling morphogenesis through differential expression-patterning of shared target genes in Arabidopsis. PLoS. Genet. 9, e1003244 (2013).Leivar, P. et al. Definition of early transcriptional circuitry involved in light-induced reversal of PIF-imposed repression of photomorphogenesis in young Arabidopsis seedlings. Plant Cell 21, 3535–3553 (2009).Willige, B. C. et al. The DELLA domain of GA INSENSITIVE mediates the interaction with the GA INSENSITIVE DWARF1A gibberellin receptor of Arabidopsis. Plant Cell 19, 1209–1220 (2007).Davière, J.-M. & Achard, P. Gibberellin signaling in plants. Develop 140, 1147–1151 (2013).Lim, S. et al. ABA-INSENSITIVE3, ABA-INSENSITIVE5, and DELLAs interact to activate the expression of SOMNUS and other high-temperature-inducible genes in imbibed seeds in Arabidopsis. Plant Cell 25, 4863–4878 (2013).Yoshida, H. et al. DELLA protein functions as a transcriptional activator through the DNA binding of the indeterminate domain family proteins. Proc. Natl Acad. Sci. USA 111, 7861–7866 (2014).Yamaguchi, N. et al. Gibberellin acts positively then negatively to control onset of flower formation in Arabidopsis. Science 344, 638–641 (2014).Stavang, J. et al. Hormonal regulation of temperature-induced growth in Arabidopsis. Plant J. 60, 589–601 (2009).Achard, P. et al. DELLAs contribute to plant photomorphogenesis. Plant Physiol. 143, 1163–1172 (2007).Arana, M. V., Marín-de la Rosa, N., Maloof, J. N., Blázquez, M. A. & Alabadí, D. Circadian oscillation of gibberellin signaling in Arabidopsis. Proc. Natl Acad. Sci. USA 108, 9292–9297 (2011).Bai, M.-Y., Fan, M., Oh, E. & Wang, Z.-Y. A triple helix-loop-helix/basic helix-loop-helix cascade controls cell elongation downstream of multiple hormonal and environmental signaling pathways in Arabidopsis. Plant Cell 24, 4917–4929 (2012).Ikeda, M., Fujiwara, S., Mitsuda, N. & Ohme-Takagi, M. A triantagonistic basic helix-loop-helix system regulates cell elongation in Arabidopsis. Plant Cell 24, 4483–4497 (2012).Yang, D.-L. et al. Plant hormone jasmonate prioritizes defense over growth by interfering with gibberellin signaling cascade. Proc. Natl Acad. Sci. USA 109, E1192–E1200 (2012).Ciolfi, A. et al. Dynamics of the shade-avoidance response in Arabidopsis. Plant Physiol. 163, 331–353 (2013).Indorf, M., Cordero, J., Neuhaus, G. & Rodríguez-Franco, M. Salt tolerance (STO), a stress-related protein, has a major role in light signalling. Plant J. 51, 563–574 (2007).Gallego-Bartolomé, J., Kami, C., Fankhauser, C., Alabadí, D. & Blázquez, M. A. A hormonal regulatory module that provides flexibility to tropic responses. Plant Physiol. 156, 1819–1825 (2011).Earley, K. W. et al. Gateway-compatible vectors for plant functional genomics and proteomics. Plant J. 45, 616–629 (2006).Tusher, V. G., Tibshirani, R. & Chu, G. Significance analysis of microarrays applied to the ionizing radiation response. Proc. Natl Acad. Sci. USA 98, 5116–5121 (2001).Gallego-Bartolomé, J. et al. Molecular mechanism for the interaction between gibberellin and brassinosteroid signaling pathways in Arabidopsis. Proc. Natl Acad. Sci. USA 109, 13446–13451 (2012).Belda-Palazón, B. et al. Aminopropyltransferases involved in polyamine biosynthesis localize preferentially in the nucleus of plant cells. PLoS ONE 7, e46907 (2012).Gallego-Bartolomé, J., Alabadí, D. & Blázquez, M. A. DELLA-induced early transcriptional changes during etiolated development in Arabidopsis thaliana. PLoS ONE 6, e23918 (2011).Piskurewicz, U. et al. The gibberellic acid signaling repressor RGL2 inhibits Arabidopsis seed germination by stimulating abscisic acid synthesis and ABI5 activity. Plant Cell 20, 2729–2745 (2008).Paz-Ares, J. REGIA, an EU project on functional genomics of transcription factors from Arabidopsis thaliana. Comp. Funct. Genomics 3, 102–108 (2002)
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