736 research outputs found

    Unique transcriptomic landscapes identified in idiopathic spontaneous and infection related preterm births compared to normal term births.

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    Preterm birth (PTB) is leading contributor to infant death in the United States and globally, yet the underlying mechanistic causes are not well understood. Histopathological studies of preterm birth suggest advanced villous maturity may have a role in idiopathic spontaneous preterm birth (isPTB). To better understand pathological and molecular basis of isPTB, we compared placental villous transcriptomes from carefully phenotyped cohorts of PTB due to infection or isPTB between 28-36 weeks gestation and healthy term placentas. Transcriptomic analyses revealed a unique expression signature for isPTB distinct from the age-matched controls that were delivered prematurely due to infection. This signature included the upregulation of three IGF binding proteins (IGFBP1, IGFBP2, and IGFBP6), supporting a role for aberrant IGF signaling in isPTB. However, within the isPTB expression signature, we detected secondary signature of inflammatory markers including TNC, C3, CFH, and C1R, which have been associated with placental maturity. In contrast, the expression signature of the gestational age-matched infected samples included upregulation of proliferative genes along with cell cycling and mitosis pathways. Together, these data suggest an isPTB molecular signature of placental hypermaturity, likely contributing to the premature activation of inflammatory pathways associated with birth and providing a molecular basis for idiopathic spontaneous birth

    A 71-nucleotide deletion in the periaxin gene in an Italian patient with late-onset slowly progressive demyelinating CMT

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    Background: Charcot-Marie-Tooth disease (CMT) constitutes a group of heterogeneous hereditary motor and sensor neuropathies. Mutations in the periaxin (PRX) gene cause CMT4F with an autosomal recessive early-onset demyelinating neuropathy and are extremely rare in a non-Romani white population. Methods: We report on a 66-year-old Italian man presenting with slowly progressive and late-onset demyelinating CMT. The molecular analysis was performed using a custom panel containing 39 genes associated with the CMT phenotype. Results: The patient harbored a homozygous PRX 71-nucleotide deletion (c.3286_3356del71, I1096fsX17). Conclusions: This is the first report that describes such a genetic mutation in a population of non-Romani origin

    Comparative transcriptomic analysis of human placentae at term and preterm delivery.

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    Preterm birth affects 1 out of every 10 infants in the United States, resulting in substantial neonatal morbidity and mortality. Currently, there are few predictive markers and few treatment options to prevent preterm birth. A healthy, functioning placenta is essential to positive pregnancy outcomes. Previous studies have suggested that placental pathology may play a role in preterm birth etiology. Therefore, we tested the hypothesis that preterm placentae may exhibit unique transcriptomic signatures compared to term samples reflective of their abnormal biology leading to this adverse outcome. We aggregated publicly available placental villous microarray data to generate a preterm and term sample dataset (n = 133, 55 preterm placentae and 78 normal term placentae). We identified differentially expressed genes using the linear regression for microarray (LIMMA) package and identified perturbations in known biological networks using Differential Rank Conservation (DIRAC). We identified 129 significantly differentially expressed genes between term and preterm placenta with 96 genes upregulated and 33 genes downregulated (P-valu

    Dynamical and stationary critical behavior of the Ising ferromagnet in a thermal gradient

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    In this paper we present and discuss results of Monte Carlo numerical simulations of the two-dimensional Ising ferromagnet in contact with a heat bath that intrinsically has a thermal gradient. The extremes of the magnet are at temperatures T1<Tc<T2T_1<T_c<T_2, where TcT_c is the Onsager critical temperature. In this way one can observe a phase transition between an ordered phase (TTcTT_c) by means of a single simulation. By starting the simulations with fully disordered initial configurations with magnetization m≡0m\equiv 0 corresponding to T=∞T=\infty, which are then suddenly annealed to a preset thermal gradient, we study the short-time critical dynamic behavior of the system. Also, by setting a small initial magnetization m=m0m=m_0, we study the critical initial increase of the order parameter. Furthermore, by starting the simulations from fully ordered configurations, which correspond to the ground state at T=0 and are subsequently quenched to a preset gradient, we study the critical relaxation dynamics of the system. Additionally, we perform stationary measurements (t→∞t\rightarrow\infty) that are discussed in terms of the standard finite-size scaling theory. We conclude that our numerical simulation results of the Ising magnet in a thermal gradient, which are rationalized in terms of both dynamic and standard scaling arguments, are fully consistent with well established results obtained under equilibrium conditions

    Implementing quality control of high-frequency radar estimates and application to gulf stream surface currents

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    Quality control procedures based on nonvelocity parameters for use with a short-range radar system are applied with slight modification to long-range radar data collected offshore of North Carolina. The radar footprint covers shelf and slope environments and includes a segment of the Gulf Stream (GS). Standard processed and quality controlled (QCD) radar data are compared with 4 months of acoustic Doppler current profiler (ADCP) time series collected at three different sites within the radar footprint. Two of the ADCP records are from the shelf and the third is on the upper slope and is frequently within the GS. Linear regression and Bland-Altman diagrams are used to quantify the comparison. QCD data at all sites have reduced scatter and improved correlation with ADCP observations relative to standard processed data. Uncertainty is reduced by approximately 20%, and linear regression slopes and correlation coefficients increase by about 0.1. At the upper slope site, the QCD data also produced a significant increase in the mean speed. Additionally, a significant increase, averaging roughly 20%, in mean speed in the GS is apparent when comparing standard processed data and QCD data, concentrated at large range and at the azimuthal extremes of radial site coverage. Shifts in the distributions of the standard processed and QCD velocity estimates are consistent with the removal of zero-mean noise from the observations, which has minimal impact where the radial site range is &lt; 70 km and a large impact at greater range in the GS where mean currents exceed 1 m s-1

    Gulf stream marine hydrokinetic energy off cape hatteras, north carolina

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    Multi-year measurements of current velocity, salinity, and temperature from fixed and vessel-mounted sensors quantify Gulf Stream (GS) marine hydrokinetic energy (MHK) resource variability and inform development off Cape Hatteras, NC. Vessel transects across the GS demonstrate a jet-like velocity structure with speeds exceeding 2.5 m/s at the surface, persistent horizontal shear throughout the jet, and strongest vertical shears within the cyclonic shear zone. Persistent equatorward flow at the base of the GS associated with the Deep Western Boundary Current (DWBC) produces a local maximum in vertical shear where stratification is weak and is postulated to be a site of strong turbulent mixing. Repeated transects at the same location demonstrate that the velocity structure depends upon whether the GS abuts the shelf slope or is offshore. Currents from a fixed acoustic Doppler current profiler (ADCP) deployed on the shoreward side of the GS exceed 1 m/s 64% of the time 40 m below the surface. The 3.75-year time series of currents from the ADCP mooring document large, roughly weekly variations in downstream and cross-stream speed (−0.5 to 2.5 m/s) and shear (± 0.05 s−1) over the entire water column due to passage of GS meanders and frontal eddies. Current reversals from the mean GS direction occur several times a month, and longer period variations in GS offshore position can result in reduced currents for weeks at a time. Unresolved small-scale shear is postulated to contribute significantly to turbulent mixing

    Ampliação do Estudo de Validação da Escala Estilos de Pensar e Criar: Desenvolvimento de uma Versão Reduzida

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    There are several measures of cognition and creative styles, however few of them are valid and short enough to be administered in different settings. Therefore, this study had two purposes: to reanalyze and obtain validity evidence of the Scale of Thinking and Creative Scale (STCS), developed by Wechsler, measuring fve styles, based on a progression of&nbsp;increasingly rigorous exploratory and confrmatory factor analytic procedures, and (b) to provide a viable psychometrically sound short version of this scale. Based on a sample of 1,752 Brazilians (55% women; ages 14 to 70) living in four states (93% from Sao Paulo), results strongly supported fve dimensions of thinking and creative style, thus indicating the validity and reliability of the abridged STCS version.Existem várias medidas de estilos de pensar e criar, porém poucas são validadas e suficientemente curtas para administração em diferentes ambientes. Portanto, este estudo teve dois objetivos: (a) reanalisar e validar a Escala de Estilos de Pensar e Criar, desenvolvida por Wechsler, que mede cinco estilos, baseando-se em uma progressão de procedimentos estatísticos rigorosos de análises fatorial exploratória e confirmatória; (b) propor uma versão reduzida dessa escala, atendendo aos parâmetros psicométricos. Baseando-se em amostra de 1.752 brasileiros (55% mulheres, idades 14-70 anos) vivendo em&nbsp;quatro estados (93% de SP), os resultados demonstraram que existem cinco dimensões dos estilos de pensar e criar, que podem ser medidos de forma válida e precisa por meio de uma versão reduzida desta escala

    Continuous Flow of Upper Labrador Sea Water around Cape Hatteras

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    Six velocity sections straddling Cape Hatteras show a deep counterflow rounding the Cape wedged beneath the poleward flowing Gulf Stream and the continental slope. This counterflow is likely the upper part of the equatorward-flowing Deep Western Boundary Current (DWBC). Hydrographic data suggest that the equatorward flow sampled by the shipboard 38 kHz ADCP comprises the Upper Labrador Sea Water (ULSW) layer and top of the Classical Labrador Sea Water (CLSW) layer. Continuous DWBC flow around the Cape implied by the closely-spaced velocity sections here is also corroborated by the trajectory of an Argo float. These findings contrast with previous studies based on floats and tracers in which the lightest DWBC constituents did not follow the boundary to cross under the Gulf Stream at Cape Hatteras but were diverted into the interior as the DWBC encountered the Gulf Stream in the crossover region. Additionally, our six quasi-synoptic velocity sections confirm that the Gulf Stream intensified markedly at that time as it approached the separation point and flowed into deeper waters. Downstream increases were observed not only in the poleward transport across the sections but also in the current's maximum speed

    Evolutionary Triangulation to Refine Genetic Association Studies of Spontaneous Preterm Birth

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    Objective The objective of this study was to apply evolutionary triangulation, a novel technique exploiting evolutionary differentiation among three populations with variable disease prevalence, to spontaneous preterm birth (PTB) genetic association studies. Study Design Single nucleotide polymorphism (SNP) allele frequency data were obtained from HapMap for CEU, GIH/MEX, and YRI/ASW populations. Evolutionary triangulation SNPs, then genes, were selected according to the overlaps of genetic population differences (CEU = outlier). Evolutionary triangulation genes were then compared with three PTB gene lists: (1) top maternal and fetal genes from a large genome-wide association study of PTB, (2) 640 genes from the database for PTB, and (3) 118 genes from a recent systematic review. Empirical p -values were calculated to determine whether evolutionary triangulation enriched for putative PTB associating genes compared with randomly selected sample genes. Results Evolutionary triangulation identified 5/17 maternal genes and 8/16 fetal genes from PTB gene list 1. From list 2, 79/640 were identified by CEU-GIH-YRI evolutionary triangulation, and 57/640 were identified by CEU-ASW-MEX evolutionary triangulation. Finally, 20/118 genes were identified by evolutionary triangulation from gene list 3. For all analyses, p < 0.001 except CEU-ASW-MEX analysis of list 3 where p = 0.002. Conclusion Genes identified in prior PTB association studies confirmed by evolutionary triangulation should be prioritized for further genetic prematurity research

    MAO A VNTR polymorphism and amygdala volume in healthy subjects

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    The X-linked Monoamine Oxidase A (MAO A) gene presents a well known functional polymorphism consisting of a variable number of tandem repeats (VNTR) (long and short variants) previously associated with altered neural function of the amygdala. Using automatic subcortical segmentation (Freesurfer), we investigated whether amygdala volume could be influenced by this genotype. We studied 109 healthy subjects (age range 18-80 years; 59 male and 50 female), 74 carrying the MAO A High-activity allele and 35 the MAO A Low-activity allele. No significant effect of the MAO A polymorphism or interaction effect between polymorphism × gender was found on amygdalar volume. Thus, our findings suggest that the reported impact of the MAO A polymorphism on amygdala function is not coupled with consistent volumetric changes in healthy subjects. Future studies are needed to investigate whether the association between volume of the amygdala and the MAO A VNTR polymorphism is influenced by social/psychological variables, such as impulsivity, trauma history and cigarette smoking behaviour, not taken into account in this work
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