561 research outputs found

    Color space distortions in patients with type 2 diabetes mellitus

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    Color vision impairment was examined in patients with type 2 diabetes mellitus (DM2) without retinopathy. We assessed the type and degree of distortions of individual color spaces. DM2 patients (n = 32), and age-matched controls (n = 20)were tested using the Farnsworth D-15 and the Lanthony D-15d tests. In addition, subsets of caps from both tests were employed in a triadic procedure (Bimler & Kirkland, 2004). Matrices of inter-cap subjective dissimilarities were estimated from each subject’s “odd-one-out” choices, and processed using non-metric multidimensional scaling. Two-dimensional color spaces, individual and group (DM2 patients; controls), were reconstructed, with the axes interpreted as the R0G and B0Y perceptual opponent systems. Compared to controls, patient results were not significant for the D-15 and D-15d. In contrast, in the triadic procedure the residual distances were significantly different compared to controls: right eye, P 0.021, and left eye, P 0.022. Color space configurations for the DM2 patients were compressed along the B0Y and R0G dimensions. The present findings agree with earlier studies demonstrating diffuse losses in early stages of DM2. The proposed method of testing uses color spaces to represent discrimination and provides more differentiated quantitative diagnosis, which may be interpreted as the perceptual color system affected. In addition, it enables the detection of very mild color vision impairment that is not captured by the D-15d test. Along with fundoscopy, individual color spaces may serve for monitoring early functional changes and thereby to support a treatment strategy

    Saturation-specific pattern of acquired colour vision deficiency in two clinical populations revealed by the method of triads

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    Subjective colour spaces were reconstructed for persons occupationally exposed to mercury (Hg) and patients with diabetes mellitus type 2, two groups at risk for acquired colour-vision deficiency, and compared with healthy normal trichromats. Judgments of colour dissimilarity were collected with the method of triads, applied to a composite assortment of colour samples. These were drawn from two widely used colour arrangement tests—10 hues from the Farnsworth D-15 test and five from the Lanthony Desaturated D-15d test, ensuring that the assortment sampled two levels of lightness and saturation. The data were analyzed with maximum-likelihood multidimensional scaling (MDS) and within a novel individual-differences MDS model to estimate subject-specific parameters. The MDS solutions for the two clinical groups showed a compression along a blue-yellow axis, limited however to desaturated hues. This result was confirmed by the individual-differences model. In addition, the clinical groups were found to place significantly higher weights on the lightness differences between stimuli, conceivably to compensate for their reduced chromatic discrimination. The specific form of colour-space distortion in the clinical groups indicated an increase in their thresholds for blue-yellow signals, providing insights into the nature of impairment mechanisms. The results have implications for stimuli and diagnostic procedures for testing individual differences in color vision, and for analyzing the responses. This approach is sensitive to distinctive patterns of subtle colour-vision impairment underestimated by the conventional D-15d test

    Producción de ensilaje de maíz blanco (Zea mays L.) de alto valor proteico con y sin mazorca asociado con dos leguminosas anuales, lablab (Lablab purpureus L.) y crotalaria (Crotalaria juncea L.).

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    In this study we evaluated the dry matter yield (DMY) and botanical composition of high protein value (QPM) white maize (Zea mays L.) with and without ear removal and associated or not with the annual legumes lablab (Lablab purpureus L.) and sunn hemp (Crotalaria juncea L.), and determined the nutritional value and products of fermentation of silage of these associations. The experiment was conducted in the Experimental Substation at Isabela, Puerto Rico, between January and April 2010 in an Oxisol soil. Lablab and sunn hemp were intercropped with white QPM corn in a randomized complete block design with six treatments and four replications. Ears with grain in the milky stage were removed from the plant at 90-d post seeding; the next day the crop was ensiled in three of the treatments [Monoculture (CWOE), associated with lablab (CLWOE) and with crotalaria (CCWOE)]. There were three analogous treatments of corn with ears present (CE, CLE and CCE). Among the latter, DMY increased with intercropping from 9,890 kg/ha (CE) to 11,256 kg/ha (CLE) and 14,786 kg/ha (CCE) whereas among the treatments without ears the increases were from 7,270 kg/ha (CWOE) to 8,667 kg/ha (CLWOE) and 10,641 kg/ha (CCWOE), thus indicating DMY losses of 2,620 kg/ha, 2,589 kg/ha and 4,145 kg/ha as a result of ear removal, for the three respective comparisons. A greater benefit to DMY occurred when sunn hemp was the intercrop (4,134 kg/ha) compared with that of lablab (1,382 kg/ha). Intercropping with sunn hemp was also more effective in reducing the proportion of weeds in the crop than with lablab (CE, 20.5%; CLE, 17.1%; CCE, 9.9%). Relative to monoculture silage, the intercropped legumes resulted in a slight reduction in dry matter (26.6 to 25.9%), but an increase is crude protein (CP) (10.0 to 11.9%) (P < 0.05). The neutral detergent fiber content of the silages was not affected, but acid detergent fiber increased from 32.9% in monoculture to 38.3% when intercropped with legume; this effect was more pronounced in the absence of ears. Corn-legume intercropping benefited weed control and increased DMY in the field and CP content of silage, without affecting the fermentation process, even when the corn ears were removed before ensiling.En este estudio se evaluó el rendimiento de materia seca (RMS) y la composición botánica de maíz blanco (Zea mays L.) de alto valor proteico (QPM, por sus siglas en inglés) con y sin mazorca, asociado o no con las leguminosas anuales lablab (Lablab purpureus L.) y crotalaria (Crotalaria juncea L). y se determinó el valor nutritivo y los productos de fermentación de los ensilajes de dichas asociaciones. El experimento se realizó en la Subestación Experimental de Isabela, Puerto Rico, entre los meses de enero y abril de 2010 en un suelo Oxisol. Se intercaló lablab y crotalaria con el maíz QPM blanco en un diseño de bloques completos aleatorizados con seis tratamientos y cuatro repeticiones. A los 90 d post siembra se removieron las mazorcas, en estado de grano lechoso, en tres de los tratamientos [Monocultivo (MSM), y maíz en asociación con lablab (MLSM) y con crotalaria (MCSM)]; al día siguiente se ensilaron las plantas. Hubo tres tratamientos análogos de maíz con mazorca (MM, MLM y MCM). Entre los tratamientos con mazorca, el RMS subió de 9,890 kg/ha (MM) a 11,256 kg/ha (MLM) y 14,786 kg/ha (MCM) con la inclusión de leguminosa, mientras entre los tratamientos sin mazorca subió de 7,270 kg/ha (MSM) a 8,667 kg/ha (MLSM) y 10,641 kg/ha (MCSM); la remoción de mazorca significó pérdidas de RMS de 2,620; 2,589; y 4,145 kg/ha para las tres respectivas comparaciones. El beneficio al RMS resultante de la asociación fue mayor con crotalaria (4,134 kg/ha) que con lablab (1,382 kg/ha). La asociación con crotalaria también fue más efectiva que aquella con lablab para reducir la proporción de maleza en el cultivo (MM, 20.5%; MLM, 17.1%; MCM, 9.9%). Relativo a los ensilajes de monocultivo, la asociación con leguminosa resultó en una leve reducción en materia seca (26.6 a 25.9%), pero un aumento en proteina bruta (PB) (10.0 a 11.9%) (P < 0.05). No se afectó el contenido de fibra detergente neutro, pero el de fibra detergente ácido aumentó de 32.9% en monocultivo a 38.3% en asociación con leguminosa, siendo dicho efecto más marcado en ausencia de mazorcas. Las asociaciones maíz-leguminosa beneficiaron el combate de malezas y el RMS en el campo e incrementaron el contenido de PB en los ensilajes sin afectar el proceso fermentativo aun cuando se removió la mazorca del maíz antes de ensilar

    Avaliação da qualidade fisiológica de sementes de pinhão manso em função do período de colheita.

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    Considerando-se a necessidade de aumento na produtividade da cultura do pinhão manso, deve-se ter especial atenção com o insumo semente, dentre outros fatores. Dessa forma, o objetivo do trabalho foi avaliar a qualidade fisiológica de sementes de pinhão manso em função do período de colheita. Foram utilizados dois lotes de sementes de pinhão manso, sendo o lote 1 composto por sementes colhidas em 2008 e o lote 2 composto por sementes colhidas em 2009. Para avaliação da qualidade fisiológica das sementes, foram realizadas as seguintes determinações:: teor de água, emergência de plântulas, índice de velocidade de emergência, plântulas anormais e sementes duras. O delineamento experimental utilizado foi inteiramente casualizado com dois lotes de sementes de pinhão manso, que consistiam nos tratamentos, e quatro repetições por tratamentos. As sementes provenientes do Lote1 (2008) apresentaram qualidade fisiológica superior. A porcentagem de sementes duras foi mais acentuada nas sementes originadas do Lote 2 (2009)

    Meta-analysis of genome-wide association studies of asthma in ethnically diverse North American populations.

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    Asthma is a common disease with a complex risk architecture including both genetic and environmental factors. We performed a meta-analysis of North American genome-wide association studies of asthma in 5,416 individuals with asthma (cases) including individuals of European American, African American or African Caribbean, and Latino ancestry, with replication in an additional 12,649 individuals from the same ethnic groups. We identified five susceptibility loci. Four were at previously reported loci on 17q21, near IL1RL1, TSLP and IL33, but we report for the first time, to our knowledge, that these loci are associated with asthma risk in three ethnic groups. In addition, we identified a new asthma susceptibility locus at PYHIN1, with the association being specific to individuals of African descent (P = 3.9 × 10(-9)). These results suggest that some asthma susceptibility loci are robust to differences in ancestry when sufficiently large samples sizes are investigated, and that ancestry-specific associations also contribute to the complex genetic architecture of asthma

    Iridoid esters from Valeriana pavonii Poepp. & Endl. as GABAA modulators: Structural insights in their binding mode and structure-activity relationship

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    Context: Valeriana pavonii Poepp. & Endl. (Caprifoliaceae), is a plant used in traditional medicine as a tranquilizer in Colombia. Valerian extracts have been widely used since ancient times for their sedative and anxiolytic properties; however, the way its active metabolites, including iridoids, interact on their respective targets is not fully understood. Aims: To isolate and identificate active iridoid esters from V. pavonii. Perform in vitro inhibition assays and computational analyses to study their possible interaction on the benzodiazepine site of the GABAA receptor. Methods: Two compounds were obtained from dichloromethane and petroleum ether fractions of V. pavonii, respectively, by chromatographic techniques. The structural elucidation was performed by NMR and spectroscopic analyses. In vitro inhibition assays of the binding of 3H-flunitrazepam (3H-FNZ) for the benzodiazepine binding site of the GABAA receptor (BDZ-bs of the GABAA receptor) were carried out. Results: Two iridoid esters, hydrine-type valepotriates (compounds 1 and 2), were reported for the first time in V. pavonii. Both iridoids, 1 and 2, inhibited the binding of 3H-FNZ on the BDZ-bs of the GABAA receptor (40% at 300 µM). Docking studies and MMGBSA calculations revealed that these compounds exhibited molecular interactions with crucial residues of the benzodiazepine site, similar to those observed for drugs like flunitrazepam, diazepam, and flumazenil. Conclusions: These findings contribute to understanding the in vivo activity of extracts of Valeriana pavonni on the central nervous system, which showed promising effects, especially as anticonvulsants, sedative-hypnotics, and antidepressants, through the modulation of the GABAergic system by hydrine-type valepotriates and its derivatives

    The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment

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    The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since July 2014. This paper describes the second data release from this phase, and the fourteenth from SDSS overall (making this, Data Release Fourteen or DR14). This release makes public data taken by SDSS-IV in its first two years of operation (July 2014-2016). Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey (eBOSS); the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data driven machine learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS website (www.sdss.org) has been updated for this release, and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020, and will be followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14 happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov 2017 (this is the "post-print" and "post-proofs" version; minor corrections only from v1, and most of errors found in proofs corrected

    ABCA7 p.G215S as potential protective factor for Alzheimer’s disease

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    Genome-wide association studies (GWASs) have been effective approaches to dissect common genetic variability underlying complex diseases in a systematic and unbiased way. Recently, GWASs have led to the discovery of over 20 susceptibility loci for Alzheimer’s disease (AD). Despite the evidence showing the contribution of these loci to AD pathogenesis, their genetic architecture has not been extensively investigated, leaving the possibility that low frequency and rare coding variants may also occur and contribute to the risk of disease. We have used exome and genome sequencing data to analyse the single independent and joint effect of rare and low frequency protein coding variants in 9 AD GWAS loci with the strongest effect sizes after APOE (BIN1, CLU, CR1, PICALM, MS4A6A, ABCA7, EPHA1, CD33, CD2AP) in a cohort of 332 sporadic AD cases and 676 elderly controls of British and North American ancestry. We identified coding variability in ABCA7 as contributing to AD risk. This locus harbors a low frequency coding variant (p.G215S, rs72973581, MAF=4.3%) conferring a modest but statistically significant protection against AD (p-value= 6x10-4, OR=0.57, 95% CI 0.41-0.80). Notably, our results are not driven by an enrichment of loss of function variants in ABCA7, recently reported as main pathogenic factor underlying AD risk at this locus. In summary, our study confirms the role of ABCA7 in AD and provide new insights that should address functional studies
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