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901.
Éverson Miguel Bianco Thiago Martins Francisco Carlos Basílio Pinheiro Rodrigo Bagueira de Vasconcellos Azeredo Valéria Laneuville Teixeira Renato Crespo Pereira 《化学与生物多样性》2015,12(11):1665-1677
Chemical investigation of the CH2Cl2 crude extract from the brown alga Canistrocarpus cervicornis (Dictyotaceae) led to isolation of one new ( 1 ) and four previously reported dolastane diterpenes ( 2 – 5 ). Their structures were characterized by 1D‐ and 2D‐NMR spectroscopic techniques, including a full single crystal X‐ray diffraction analysis for 1, 2 , and 4 . In addition, the new structure 1 was assayed as chemical defense inhibiting the feeding by the sea urchin Lytechinus variegatus. This study constitutes an additional report broadening the known spectrum of action and defensive roles of secondary metabolites of the C. cervicornis and Dictyotales species. 相似文献
902.
Verónica Guajardo Simón Solís Boris Sagredo Felipe Gainza Carlos Mu?oz Ksenija Gasic Patricio Hinrichsen 《PloS one》2015,10(5)
Linkage maps are valuable tools in genetic and genomic studies. For sweet cherry, linkage maps have been constructed using mainly microsatellite markers (SSRs) and, recently, using single nucleotide polymorphism markers (SNPs) from a cherry 6K SNP array. Genotyping-by-sequencing (GBS), a new methodology based on high-throughput sequencing, holds great promise for identification of high number of SNPs and construction of high density linkage maps. In this study, GBS was used to identify SNPs from an intra-specific sweet cherry cross. A total of 8,476 high quality SNPs were selected for mapping. The physical position for each SNP was determined using the peach genome, Peach v1.0, as reference, and a homogeneous distribution of markers along the eight peach scaffolds was obtained. On average, 65.6% of the SNPs were present in genic regions and 49.8% were located in exonic regions. In addition to the SNPs, a group of SSRs was also used for construction of linkage maps. Parental and consensus high density maps were constructed by genotyping 166 siblings from a ‘Rainier’ x ‘Rivedel’ (Ra x Ri) cross. Using Ra x Ri population, 462, 489 and 985 markers were mapped into eight linkage groups in ‘Rainier’, ‘Rivedel’ and the Ra x Ri map, respectively, with 80% of mapped SNPs located in genic regions. Obtained maps spanned 549.5, 582.6 and 731.3 cM for ‘Rainier’, ‘Rivedel’ and consensus maps, respectively, with an average distance of 1.2 cM between adjacent markers for both ‘Rainier’ and ‘Rivedel’ maps and of 0.7 cM for Ra x Ri map. High synteny and co-linearity was observed between obtained maps and with Peach v1.0. These new high density linkage maps provide valuable information on the sweet cherry genome, and serve as the basis for identification of QTLs and genes relevant for the breeding of the species. 相似文献
903.
Hudson T. Pinheiro Eric Mazzei Rodrigo L. Moura Gilberto M. Amado-Filho Alfredo Carvalho-Filho Adriana C. Braga Paulo A. S. Costa Beatrice P. Ferreira Carlos Eduardo L. Ferreira Sergio R. Floeter Ronaldo B. Francini-Filho Jo?o Luiz Gasparini Raphael M. Macieira Agnaldo S. Martins George Olavo Caio R. Pimentel Luiz A. Rocha Ivan Sazima Thiony Simon Jo?o Batista Teixeira Lucas B. Xavier Jean-Christophe Joyeux 《PloS one》2015,10(3)
Despite a strong increase in research on seamounts and oceanic islands ecology and biogeography, many basic aspects of their biodiversity are still unknown. In the southwestern Atlantic, the Vitória-Trindade Seamount Chain (VTC) extends ca. 1,200 km offshore the Brazilian continental shelf, from the Vitória seamount to the oceanic islands of Trindade and Martin Vaz. For a long time, most of the biological information available regarded its islands. Our study presents and analyzes an extensive database on the VTC fish biodiversity, built on data compiled from literature and recent scientific expeditions that assessed both shallow to mesophotic environments. A total of 273 species were recorded, 211 of which occur on seamounts and 173 at the islands. New records for seamounts or islands include 191 reef fish species and 64 depth range extensions. The structure of fish assemblages was similar between islands and seamounts, not differing in species geographic distribution, trophic composition, or spawning strategies. Main differences were related to endemism, higher at the islands, and to the number of endangered species, higher at the seamounts. Since unregulated fishing activities are common in the region, and mining activities are expected to drastically increase in the near future (carbonates on seamount summits and metals on slopes), this unique biodiversity needs urgent attention and management. 相似文献
904.
Carlos Eduardo Pinzón-Flórez Julián Alfredo Fernández-Ni?o Myriam Ruiz-Rodríguez álvaro J. Idrovo Abel Armando Arredondo López 《PloS one》2015,10(3)
Aims
To assess the association of social determinants on the performance of health systems around the world.Methods
A transnational ecological study was conducted with an observation level focused on the country. In order to research on the strength of the association between the annual maternal and child mortality in 154 countries and social determinants: corruption, democratization, income inequality and cultural fragmentation, we used a mixed linear regression model for repeated measures with random intercepts and a conglomerate-based geographical analysis, between 2000 and 2010.Results
Health determinants with a significant association on child mortality(<1year): higher access to water (βa Quartile 4(Q4) vs Quartile 1(Q1) = -6,14; 95%CI: -11,63 to -0,73), sanitation systems, (Q4 vs Q1 = -25,58; 95%CI: -31,91 to -19,25), % measles vaccination coverage (Q4 vs Q1 = -7.35; 95%CI: -10,18 to -4,52), % of births attended by a healthcare professional (Q4 vs Q1 = -7,91; 95%CI: -11,36 to -4,52) and a % of the total health expenditure (Q3 vs Q1 = -2,85; 95%CI: -4,93 to -0,7). Ethnic fragmentation (Q4 vs Q1 = 9,93; 95%CI: -0.03 to 19.89) had a marginal effect. For child mortality<5 years, an association was found for these variables and democratization (not free vs free = 11,23; 95%CI: -0,82 to 23,29), out-of-pocket expenditure (Q1 vs Q4 = 17,71; 95%CI: 5,86 to 29,56). For MMR (Maternal mortality ratio), % of access to water for all the quartiles, % of access to sanitation systems, (Q3 vs Q1 = -171,15; 95%CI: -281,29 to -61), birth attention by a healthcare professional (Q4 vs Q1 = -231,23; 95%CI: -349,32 to -113,15), and having corrupt government (Q3 vs Q1 = 83,05; 95%CI: 33,10 to 133).Conclusions
Improving access to water and sanitation systems, decreasing corruption in the health sector must become priorities in health systems. The ethno-linguistic cultural fragmentation and the detriment of democracy turn out to be two factors related to health results. 相似文献905.
Marina Figueiredo Magalh?es Almir Vieira Dibai-Filho Elaine Caldeira de Oliveira Guirro Carlos Eduardo Girasol Alessandra Kelly de Oliveira Fabiana Rodrigues Cancio Dias Rinaldo Roberto de Jesus Guirro 《PloS one》2015,10(6)
Some assessment and diagnosis methods require palpation or the application of certain forces on the skin, which affects the structures beneath, we highlight the importance of defining possible influences on skin temperature as a result of this physical contact. Thus, the aim of the present study is to determine the ideal time for performing thermographic examination after palpation based on the assessment of skin temperature evolution. Randomized and crossover study carried out with 15 computer-user volunteers of both genders, between 18 and 45 years of age, who were submitted to compressive forces of 0, 1, 2 and 3 kg/cm2 for 30 seconds with a washout period of 48 hours using a portable digital dynamometer. Compressive forces were applied on the following spots on the dominant upper limb: myofascial trigger point in the levator scapulae, biceps brachii muscle and palmaris longus tendon. Volunteers were examined by means of infrared thermography before and after the application of compressive forces (15, 30, 45 and 60 minutes). In most comparisons made over time, a significant decrease was observed 30, 45 and 60 minutes after the application of compressive forces (p < 0.05) on the palmaris longus tendon and biceps brachii muscle. However, no difference was observed when comparing the different compressive forces (p > 0.05). In conclusion, infrared thermography can be used after assessment or diagnosis methods focused on the application of forces on tendons and muscles, provided the procedure is performed 15 minutes after contact with the skin. Regarding to the myofascial trigger point, the thermographic examination can be performed within 60 minutes after the contact with the skin. 相似文献
906.
María F. Garcés Elizabeth Sanchez Luisa F. Cardona Elkin L. Simanca Iván González Luis G. Leal José A. Mora Andrés Bedoya Juan P. Alzate ángel Y. Sánchez Javier H. Eslava-Schmalbach Roberto Franco-Vega Mario O. Parra Ariel I. Ruíz—Parra Carlos Diéguez Rubén Nogueiras Jorge E. Caminos 《PloS one》2015,10(6)
Background
Meteorin (METRN) is a recently described neutrophic factor with angiogenic properties. This is a nested case-control study in a longitudinal cohort study that describes the serum profile of METRN during different periods of gestation in healthy and preeclamptic pregnant women. Moreover, we explore the possible application of METRN as a biomarker.Methods and Findings
Serum METRN was measured by ELISA in a longitudinal prospective cohort study in 37 healthy pregnant women, 16 mild preeclamptic women, and 20 healthy non-pregnant women during the menstrual cycle with the aim of assessing serum METRN levels and its correlations with other metabolic parameters. Immunostaining for METRN protein was performed in placenta. A multivariate logistic regression model was proposed and a classifier model was formulated for predicting preeclampsia in early and middle pregnancy. The performance in classification was evaluated using measures such as sensitivity, specificity, and the receiver operating characteristic (ROC) curve. In healthy pregnant women, serum METRN levels were significantly elevated in early pregnancy compared to middle and late pregnancy. METRN levels are significantly lower only in early pregnancy in preeclamptic women when compared to healthy pregnant women. Decision trees that did not include METRN levels in the first trimester had a reduced sensitivity of 56% in the detection of preeclamptic women, compared to a sensitivity of 69% when METRN was included.Conclusions
The joint measurements of circulating METRN levels in the first trimester and systolic blood pressure and weight in the second trimester significantly increase the probabilities of predicting preeclampsia. 相似文献907.
Ana L. Teixeira Francisca Dias Marta Ferreira Mónica Gomes Juliana I. Santos Francisco Lobo Joaquina Maurício José Carlos Machado Rui Medeiros 《PloS one》2015,10(4)
The epidermal growth factor (EGF) is responsible for the activation of intracellular signal transducers that act on cell-cycle progression, cell motility, angiogenesis and inhibition of apoptosis. However, cells can block these effects activating opposite signaling pathways, such as the transforming growth factor beta 1 (TGFβ1) pathway. Thus changes in expression levels of EGF and TGFB1 in renal cells might modulate the renal cell carcinoma (RCC) development, in consequence of changes in regulatory elements of signaling networks such as the microRNAs (miRNAs). Our purpose was to investigate the synergic role of EGF+61G>A and TGFB1+869T>C polymorphisms in RCC development. Genetic polymorphisms were studied by allelic discrimination using real-time PCR in 133 RCC patients vs. 443 healthy individuals. The circulating EGF/EGFR-MAPK-related miR-7, miR-221 and miR-222 expression was analyzed by a quantitative real-time PCR in plasma from 22 RCC patients vs. 27 healthy individuals. The intermediate/high genetic proliferation profile patients carriers present a significantly reduced time-to-progression and a higher risk of an early relapse compared with the low genetic proliferation profile carriers (HR = 8.8, P = 0.038) with impact in a lower overall survival (Log rank test, P = 0.047). The RCC patients presented higher circulating expression levels of miR-7 than healthy individuals (6.1-fold increase, P<0.001). Moreover, the intermediate/high genetic proliferation profile carriers present an increase in expression levels of miR-7, miR-221 and miR-222 during the RCC development and this increase is not observed in low genetic proliferation profile (P<0.001, P = 0.004, P<0.001, respectively). The stimulus to angiogenesis, cell-cycle progression and tumoral cells invasion, through activation of EGFR/MAPK signaling pathway in intermediate/high proliferation profile carriers is associated with an early disease progression, resulting in a poor overall survival. We also demonstrated that the intermediate/high proliferation profile is an unfavorable prognostic factor of RCC and miR-7, miR-221 and miR-222 expressions may be useful phenotype biomarkers of EGFR/MAPK activation. 相似文献
908.
Sherry Towers Shehzad Afzal Gilbert Bernal Nadya Bliss Shala Brown Baltazar Espinoza Jasmine Jackson Julia Judson-Garcia Maryam Khan Michael Lin Robert Mamada Victor M. Moreno Fereshteh Nazari Kamaldeen Okuneye Mary L. Ross Claudia Rodriguez Jan Medlock David Ebert Carlos Castillo-Chavez 《PloS one》2015,10(6)
Background
In the weeks following the first imported case of Ebola in the U. S. on September 29, 2014, coverage of the very limited outbreak dominated the news media, in a manner quite disproportionate to the actual threat to national public health; by the end of October, 2014, there were only four laboratory confirmed cases of Ebola in the entire nation. Public interest in these events was high, as reflected in the millions of Ebola-related Internet searches and tweets performed in the month following the first confirmed case. Use of trending Internet searches and tweets has been proposed in the past for real-time prediction of outbreaks (a field referred to as “digital epidemiology”), but accounting for the biases of public panic has been problematic. In the case of the limited U. S. Ebola outbreak, we know that the Ebola-related searches and tweets originating the U. S. during the outbreak were due only to public interest or panic, providing an unprecedented means to determine how these dynamics affect such data, and how news media may be driving these trends.Methodology
We examine daily Ebola-related Internet search and Twitter data in the U. S. during the six week period ending Oct 31, 2014. TV news coverage data were obtained from the daily number of Ebola-related news videos appearing on two major news networks. We fit the parameters of a mathematical contagion model to the data to determine if the news coverage was a significant factor in the temporal patterns in Ebola-related Internet and Twitter data.Conclusions
We find significant evidence of contagion, with each Ebola-related news video inspiring tens of thousands of Ebola-related tweets and Internet searches. Between 65% to 76% of the variance in all samples is described by the news media contagion model. 相似文献909.
Deysi V. T. Wong Roberto C. P. Lima-Júnior Cibele B. M. Carvalho Vanessa F. Borges Carlos W. S. Wanderley Amanda X. C. Bem Caio A. V. G. Leite Maraiza A. Teixeira Gabriela L. P. Batista Rangel L. Silva Thiago M. Cunha Gerly A. C. Brito Paulo R. C. Almeida Fernando Q. Cunha Ronaldo A. Ribeiro 《PloS one》2015,10(10)
Intestinal mucositis is a common side effect of irinotecan-based anticancer regimens. Mucositis causes cell damage, bacterial/endotoxin translocation and production of cytokines including IL–1 and IL–18. These molecules and toll-like receptors (TLRs) activate a common signaling pathway that involves the Myeloid Differentiation adaptor protein, MyD88, whose role in intestinal mucositis is unknown. Then, we evaluated the involvement of TLRs and MyD88 in the pathogenesis of irinotecan-induced intestinal mucositis. MyD88-, TLR2- or TLR9-knockout mice and C57BL/6 (WT) mice were given either saline or irinotecan (75 mg/kg, i.p. for 4 days). On day 7, animal survival, diarrhea and bacteremia were assessed, and following euthanasia, samples of the ileum were obtained for morphometric analysis, myeloperoxidase (MPO) assay and measurement of pro-inflammatory markers. Irinotecan reduced the animal survival (50%) and induced a pronounced diarrhea, increased bacteremia, neutrophil accumulation in the intestinal tissue, intestinal damage and more than twofold increased expression of MyD88 (200%), TLR9 (400%), TRAF6 (236%), IL–1β (405%), IL–18 (365%), COX–2 (2,777%) and NF-κB (245%) in the WT animals when compared with saline-injected group (P<0.05). Genetic deletion of MyD88, TLR2 or TLR9 effectively controlled the signs of intestinal injury when compared with irinotecan-administered WT controls (P<0.05). In contrast to the MyD88-/- and TLR2-/- mice, the irinotecan-injected TLR9-/- mice showed a reduced survival, a marked diarrhea and an enhanced expression of IL–18 versus irinotecan-injected WT controls. Additionally, the expression of MyD88 was reduced in the TLR2-/- or TLR9-/- mice. This study shows a critical role of the MyD88-mediated TLR2 and TLR9 signaling in the pathogenesis of irinotecan-induced intestinal mucositis. 相似文献
910.
Cecilia Herraiz Conchi Olivares Maria Castejón-Gri?án Marta Abrisqueta Celia Jiménez-Cervantes José Carlos García-Borrón 《PloS one》2015,10(12)
The melanocortin 1 receptor gene (MC1R) expressed in melanocytes is a major determinant of skin pigmentation. It encodes a Gs protein-coupled receptor activated by α-melanocyte stimulating hormone (αMSH). Human MC1R has an inefficient poly(A) site allowing intergenic splicing with its downstream neighbour Tubulin-β-III (TUBB3). Intergenic splicing produces two MC1R isoforms, designated Iso1 and Iso2, bearing the complete seven transmembrane helices from MC1R fused to TUBB3-derived C-terminal extensions, in-frame for Iso1 and out-of-frame for Iso2. It has been reported that exposure to ultraviolet radiation (UVR) might promote an isoform switch from canonical MC1R (MC1R-001) to the MC1R-TUBB3 chimeras, which might lead to novel phenotypes required for tanning. We expressed the Flag epitope-tagged intergenic isoforms in heterologous HEK293T cells and human melanoma cells, for functional characterization. Iso1 was expressed with the expected size. Iso2 yielded a doublet of Mr significantly lower than predicted, and impaired intracellular stability. Although Iso1- and Iso2 bound radiolabelled agonist with the same affinity as MC1R-001, their plasma membrane expression was strongly reduced. Decreased surface expression mostly resulted from aberrant forward trafficking, rather than high rates of endocytosis. Functional coupling of both isoforms to cAMP was lower than wild-type, but ERK activation upon binding of αMSH was unimpaired, suggesting imbalanced signaling from the splice variants. Heterodimerization of differentially labelled MC1R-001 with the splicing isoforms analyzed by co-immunoprecipitation was efficient and caused decreased surface expression of binding sites. Thus, UVR-induced MC1R isoforms might contribute to fine-tune the tanning response by modulating MC1R-001 availability and functional parameters. 相似文献