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1.
  • Akrami, Y., et al. (author)
  • Planck 2018 results IX. Constraints on primordial non-Gaussianity
  • 2020
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 641
  • Journal article (peer-reviewed)abstract
    • We analyse the Planck full-mission cosmic microwave background (CMB) temperature and E-mode polarization maps to obtain constraints on primordial non-Gaussianity (NG). We compare estimates obtained from separable template-fitting, binned, and optimal modal bispectrum estimators, finding consistent values for the local, equilateral, and orthogonal bispectrum amplitudes. Our combined temperature and polarization analysis produces the following final results: (local)(NL) = -0.9 +/- 5.1 f NL local = - 0.9 +/- 5.1 ; f(NL)(equil) = -26 +/- 47 f NL equil = - 26 +/- 47 ; and f(NL)(ortho) = -38 +/- 24 f NL ortho = - 38 +/- 24 (68% CL, statistical). These results include low-multipole (4 <= l< 40) polarization data that are not included in our previous analysis. The results also pass an extensive battery of tests (with additional tests regarding foreground residuals compared to 2015), and they are stable with respect to our 2015 measurements (with small fluctuations, at the level of a fraction of a standard deviation, which is consistent with changes in data processing). Polarization-only bispectra display a significant improvement in robustness; they can now be used independently to set primordial NG constraints with a sensitivity comparable to WMAP temperature-based results and they give excellent agreement. In addition to the analysis of the standard local, equilateral, and orthogonal bispectrum shapes, we consider a large number of additional cases, such as scale-dependent feature and resonance bispectra, isocurvature primordial NG, and parity-breaking models, where we also place tight constraints but do not detect any signal. The non-primordial lensing bispectrum is, however, detected with an improved significance compared to 2015, excluding the null hypothesis at 3.5. Beyond estimates of individual shape amplitudes, we also present model-independent reconstructions and analyses of the Planck CMB bispectrum. Our final constraint on the local primordial trispectrum shape is g(NL)(local) = (-5.8 +/- 6.5) x 10(4) g NL local = ( - 5.8 +/- 6.5 ) x 10 4 (68% CL, statistical), while constraints for other trispectrum shapes are also determined. Exploiting the tight limits on various bispectrum and trispectrum shapes, we constrain the parameter space of different early-Universe scenarios that generate primordial NG, including general single-field models of inflation, multi-field models (e.g. curvaton models), models of inflation with axion fields producing parity-violation bispectra in the tensor sector, and inflationary models involving vector-like fields with directionally-dependent bispectra. Our results provide a high-precision test for structure-formation scenarios, showing complete agreement with the basic picture of the Lambda CDM cosmology regarding the statistics of the initial conditions, with cosmic structures arising from adiabatic, passive, Gaussian, and primordial seed perturbations.
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2.
  • Abdalla, E., et al. (author)
  • Cosmology intertwined : A review of the particle physics, astrophysics, and cosmology associated with the cosmological tensions and anomalies
  • 2022
  • In: Journal of High Energy Astrophysics. - : Elsevier BV. - 2214-4048 .- 2214-4056. ; 34, s. 49-211
  • Journal article (peer-reviewed)abstract
    • The standard Λ Cold Dark Matter (ΛCDM) cosmological model provides a good description of a wide range of astrophysical and cosmological data. However, there are a few big open questions that make the standard model look like an approximation to a more realistic scenario yet to be found. In this paper, we list a few important goals that need to be addressed in the next decade, taking into account the current discordances between the different cosmological probes, such as the disagreement in the value of the Hubble constant H0, the σ8–S8 tension, and other less statistically significant anomalies. While these discordances can still be in part the result of systematic errors, their persistence after several years of accurate analysis strongly hints at cracks in the standard cosmological scenario and the necessity for new physics or generalisations beyond the standard model. In this paper, we focus on the 5.0σ tension between the Planck CMB estimate of the Hubble constant H0 and the SH0ES collaboration measurements. After showing the H0 evaluations made from different teams using different methods and geometric calibrations, we list a few interesting new physics models that could alleviate this tension and discuss how the next decade's experiments will be crucial. Moreover, we focus on the tension of the Planck CMB data with weak lensing measurements and redshift surveys, about the value of the matter energy density Ωm, and the amplitude or rate of the growth of structure (σ8,fσ8). We list a few interesting models proposed for alleviating this tension, and we discuss the importance of trying to fit a full array of data with a single model and not just one parameter at a time. Additionally, we present a wide range of other less discussed anomalies at a statistical significance level lower than the H0–S8 tensions which may also constitute hints towards new physics, and we discuss possible generic theoretical approaches that can collectively explain the non-standard nature of these signals. Finally, we give an overview of upgraded experiments and next-generation space missions and facilities on Earth that will be of crucial importance to address all these open questions. 
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3.
  • Adam, R., et al. (author)
  • Planck 2015 results IX. Diffuse component separation : CMB maps
  • 2016
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 594
  • Journal article (peer-reviewed)abstract
    • We present foreground-reduced cosmic microwave background (CMB) maps derived from the full Planck data set in both temperature and polarization. Compared to the corresponding Planck 2013 temperature sky maps, the total data volume is larger by a factor of 3.2 for frequencies between 30 and 70 GHz, and by 1.9 for frequencies between 100 and 857 GHz. In addition, systematic errors in the forms of temperature-topolarization leakage, analogue-to-digital conversion uncertainties, and very long time constant errors have been dramatically reduced, to the extent that the cosmological polarization signal may now be robustly recovered on angular scales l greater than or similar to 40. On the very largest scales, instrumental systematic residuals are still non-negligible compared to the expected cosmological signal, and modes with l < 20 are accordingly suppressed in the current polarization maps by high-pass filtering. As in 2013, four different CMB component separation algorithms are applied to these observations, providing a measure of stability with respect to algorithmic and modelling choices. The resulting polarization maps have rms instrumental noise ranging between 0.21 and 0.27 mu K averaged over 55' pixels, and between 4.5 and 6.1 mu K averaged over 3.'4 pixels. The cosmological parameters derived from the analysis of temperature power spectra are in agreement at the 1 sigma level with the Planck 2015 likelihood. Unresolved mismatches between the noise properties of the data and simulations prevent a satisfactory description of the higher-order statistical properties of the polarization maps. Thus, the primary applications of these polarization maps are those that do not require massive simulations for accurate estimation of uncertainties, for instance estimation of cross-spectra and cross-correlations, or stacking analyses. However, the amplitude of primordial non-Gaussianity is consistent with zero within 2 sigma for all local, equilateral, and orthogonal configurations of the bispectrum, including for polarization E-modes. Moreover, excellent agreement is found regarding the lensing B-mode power spectrum, both internally among the various component separation codes and with the best-fit Planck 2015 Lambda cold dark matter model.
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4.
  • Adam, R., et al. (author)
  • Planck intermediate results XLVII. Planck constraints on reionization history
  • 2016
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 596
  • Journal article (peer-reviewed)abstract
    • We investigate constraints on cosmic reionization extracted from the Planck cosmic microwave background (CMB) data. We combine the Planck CMB anisotropy data in temperature with the low-multipole polarization data to fit Lambda CDM models with various parameterizations of the reionization history. We obtain a Thomson optical depth tau = 0.058 +/- 0.012 for the commonly adopted instantaneous reionization model. This confirms, with data solely from CMB anisotropies, the low value suggested by combining Planck 2015 results with other data sets, and also reduces the uncertainties. We reconstruct the history of the ionization fraction using either a symmetric or an asymmetric model for the transition between the neutral and ionized phases. To determine better constraints on the duration of the reionization process, we also make use of measurements of the amplitude of the kinetic Sunyaev-Zeldovich (kSZ) effect using additional information from the high-resolution Atacama Cosmology Telescope and South Pole Telescope experiments. The average redshift at which reionization occurs is found to lie between z = 7.8 and 8.8, depending on the model of reionization adopted. Using kSZ constraints and a redshift-symmetric reionization model, we find an upper limit to the width of the reionization period of Delta z < 2.8. In all cases, we find that the Universe is ionized at less than the 10% level at redshifts above z similar or equal to 10. This suggests that an early onset of reionization is strongly disfavoured by the Planck data. We show that this result also reduces the tension between CMB-based analyses and constraints from other astrophysical sources.
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5.
  • Ade, P. A. R., et al. (author)
  • Planck 2015 results XVII. Constraints on primordial non-Gaussianity
  • 2016
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 594
  • Journal article (peer-reviewed)abstract
    • The Planck full mission cosmic microwave background (CMB) temperature and E-mode polarization maps are analysed to obtain constraints on primordial non-Gaussianity (NG). Using three classes of optimal bispectrum estimators - separable template-fitting (KSW), binned, and modal we obtain consistent values for the primordial local, equilateral, and orthogonal bispectrum amplitudes, quoting as our final result from temperature alone f(NL)(local) = 2.5 +/- 5.7, f(NL)(equil) = 16 +/- 70, and f(NL)(ortho) = 34 +/- 33 (68% CL, statistical). Combining temperature and polarization data we obtain f(NL)(local) = 0.8 +/- 5.0, f(NL)(equil) = 4 +/- 43, and f(NL)(ortho) = 26 +/- 21 (68% CL, statistical). The results are based on comprehensive cross-validation of these estimators on Gaussian and non-Gaussian simulations, are stable across component separation techniques, pass an extensive suite of tests, and are consistent with estimators based on measuring the Minkowski functionals of the CMB. The effect of time-domain de-glitching systematics on the bispectrum is negligible. In spite of these test outcomes we conservatively label the results including polarization data as preliminary, owing to a known mismatch of the noise model in simulations and the data. Beyond estimates of individual shape amplitudes, we present model-independent, three-dimensional reconstructions of the Planck CMB bispectrum and derive constraints on early universe scenarios that generate primordial NG, including general single-field models of inflation, axion inflation, initial state modifications, models producing parity-violating tensor bispectra, and directionally dependent vector models. We present a wide survey of scale-dependent feature and resonance models, accounting for the look elsewhere effect in estimating the statistical significance of features. We also look for isocurvature NG, and find no signal, but we obtain constraints that improve significantly with the inclusion of polarization. The primordial trispectrum amplitude in the local model is constrained to be g(NL)(local) = (9.0 +/- 7.7) x 10(4) (68% CL statistical), and we perform an analysis of trispectrum shapes beyond the local case. The global picture that emerges is one of consistency with the premises of the Lambda CDM cosmology, namely that the structure we observe today was sourced by adiabatic, passive, Gaussian, and primordial seed perturbations.
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6.
  • Aghanim, N., et al. (author)
  • Planck intermediate results LIII. Detection of velocity dispersion from the kinetic Sunyaev-Zeldovich effect
  • 2018
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 617
  • Journal article (peer-reviewed)abstract
    • Using the Planck full-mission data, we present a detection of the temperature (and therefore velocity) dispersion due to the kinetic Sunyaev-Zeldovich (kSZ) effect from clusters of galaxies. To suppress the primary CMB and instrumental noise we derive a matched filter and then convolve it with the Planck foreground-cleaned 2D- ILC maps. By using the Meta Catalogue of X-ray detected Clusters of galaxies (MCXC), we determine the normalized rms dispersion of the temperature fluctuations at the positions of clusters, finding that this shows excess variance compared with the noise expectation. We then build an unbiased statistical estimator of the signal, determining that the normalized mean temperature dispersion of 1526 clusters is <(Delta T/T)(2))> = (1.64 +/- 0.48) x 10(-11). However, comparison with analytic calculations and simulations suggest that around 0.7 sigma of this result is due to cluster lensing rather than the kSZ effect. By correcting this, the temperature dispersion is measured to be <(Delta T/T)(2))> = (1.35 +/- 0.48) x 10(-11), which gives a detection at the 2.8 sigma level. We further convert uniform-weight temperature dispersion into a measurement of the line-of-sight velocity dispersion, by using estimates of the optical depth of each cluster (which introduces additional uncertainty into the estimate). We find that the velocity dispersion is (v(2)) = (123 000 +/- 71 000) (km s(-1))(2), which is consistent with findings from other large-scale structure studies, and provides direct evidence of statistical homogeneity on scales of 600 h(-1) Mpc. Our study shows the promise of using cross-correlations of the kSZ effect with large-scale structure in order to constrain the growth of structure.
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7.
  • Aghanim, N., et al. (author)
  • Planck intermediate results XLVI. Reduction of large-scale systematic effects in HFI polarization maps and estimation of the reionization optical depth
  • 2016
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 596
  • Journal article (peer-reviewed)abstract
    • This paper describes the identification, modelling, and removal of previously unexplained systematic effects in the polarization data of the Planck High Frequency Instrument (HFI) on large angular scales, including new mapmaking and calibration procedures, new and more complete end-to-end simulations, and a set of robust internal consistency checks on the resulting maps. These maps, at 100, 143, 217, and 353 GHz, are early versions of those that will be released in final form later in 2016. The improvements allow us to determine the cosmic reionization optical depth tau using, for the first time, the low-multipole EE data from HFI, reducing significantly the central value and uncertainty, and hence the upper limit. Two different likelihood procedures are used to constrain tau from two estimators of the CMB E- and B-mode angular power spectra at 100 and 143 GHz, after debiasing the spectra from a small remaining systematic contamination. These all give fully consistent results. A further consistency test is performed using cross-correlations derived from the Low Frequency Instrument maps of the Planck 2015 data release and the new HFI data. For this purpose, end-to-end analyses of systematic effects from the two instruments are used to demonstrate the near independence of their dominant systematic error residuals. The tightest result comes from the HFI-based tau posterior distribution using the maximum likelihood power spectrum estimator from EE data only, giving a value 0.055 +/- 0.009. In a companion paper these results are discussed in the context of the best-fit Planck Lambda CDM cosmological model and recent models of reionization.
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8.
  • Aghanim, N., et al. (author)
  • Planck intermediate results LI. Features in the cosmic microwave background temperature power spectrum and shifts in cosmological parameters
  • 2017
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 607
  • Journal article (peer-reviewed)abstract
    • The six parameters of the standard Lambda CDM model have best-fit values derived from the Planck temperature power spectrum that are shifted somewhat from the best-fit values derived from WMAP data. These shifts are driven by features in the Planck temperature power spectrum at angular scales that had never before been measured to cosmic-variance level precision. We have investigated these shifts to determine whether they are within the range of expectation and to understand their origin in the data. Taking our parameter set to be the optical depth of the reionized intergalactic medium tau, the baryon density omega(b), the matter density omega(m), the angular size of the sound horizon theta(*), the spectral index of the primordial power spectrum, n(s), and A(s)e(-2 pi) (where As is the amplitude of the primordial power spectrum), we have examined the change in best-fit values between a WMAP-like large angular-scale data set (with multipole moment l < 800 in the Planck temperature power spectrum) and an all angular-scale data set (l < 2500 Planck temperature power spectrum), each with a prior on tau of 0.07 +/- 0.02. We find that the shifts, in units of the 1 sigma expected dispersion for each parameter, are {Delta tau, Delta A(s)e(-2 tau), Delta n(s), Delta omega(m), Delta omega(b), Delta theta(*)} = {-1.7, -2.2, 1.2, 2.0, 1.1, 0.9}, with a chi(2) value of 8.0. We find that this chi(2) value is exceeded in 15% of our simulated data sets, and that a parameter deviates by more than 2.2 sigma in 9% of simulated data sets, meaning that the shifts are not unusually large. Comparing l < 800 instead to l > 800, or splitting at a different multipole, yields similar results. We examined the l < 800 model residuals in the l > 800 power spectrum data and find that the features there that drive these shifts are a set of oscillations across a broad range of angular scales. Although they partly appear similar to the effects of enhanced gravitational lensing, the shifts in Lambda CDM parameters that arise in response to these features correspond to model spectrum changes that are predominantly due to non-lensing effects; the only exception is tau, which, at fixed A(s)e(-2 tau), affects the l > 800 temperature power spectrum solely through the associated change in As and the impact of that on the lensing potential power spectrum. We also ask, what is it about the power spectrum at l < 800 that leads to somewhat different best-fit parameters than come from the full l range? We find that if we discard the data at l < 30, where there is a roughly 2 sigma downward fluctuation in power relative to the model that best fits the full l range, the l < 800 best-fit parameters shift significantly towards the l < 2500 best-fit parameters. In contrast, including l < 30, this previously noted low-l deficit drives ns up and impacts parameters correlated with ns, such as omega(m) and H-0. As expected, the l < 30 data have a much greater impact on the l < 800 best fit than on the l < 2500 best fit. So although the shifts are not very significant, we find that they can be understood through the combined effects of an oscillatory-like set of high-l residuals and the deficit in low-l power, excursions consistent with sample variance that happen to map onto changes in cosmological parameters. Finally, we examine agreement between Planck TT data and two other CMB data sets, namely the Planck lensing reconstruction and the TT power spectrum measured by the South Pole Telescope, again finding a lack of convincing evidence of any significant deviations in parameters, suggesting that current CMB data sets give an internally consistent picture of the Lambda CDM model.
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9.
  • Aghanim, N., et al. (author)
  • Planck intermediate results XLIX. Parity-violation constraints from polarization data
  • 2016
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 596
  • Journal article (peer-reviewed)abstract
    • Parity-violating extensions of the standard electromagnetic theory cause in vacuo rotation of the plane of polarization of propagating photons. This effect, also known as cosmic birefringence, has an impact on the cosmic microwave background (CMB) anisotropy angular power spectra, producing non-vanishing T-B and E-B correlations that are otherwise null when parity is a symmetry. Here we present new constraints on an isotropic rotation, parametrized by the angle alpha, derived from Planck 2015 CMB polarization data. To increase the robustness of our analyses, we employ two complementary approaches, in harmonic space and in map space, the latter based on a peak stacking technique. The two approaches provide estimates for alpha that are in agreement within statistical uncertainties and are very stable against several consistency tests. Considering the T-B and E-B information jointly, we find alpha = 0 degrees: 31 +/- 0 degrees.05 (stat:) +/- 0 degrees:28 (syst:) from the harmonic analysis and alpha = 0 degrees.35 +/- 0 degrees.05 (stat :) 0 degrees.28 (syst :) from the stacking approach. These constraints are compatible with no parity violation and are dominated by the systematic uncertainty in the orientation of Planck's polarization-sensitive bolometers.
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10.
  • Aghanim, N., et al. (author)
  • Planck intermediate results XLVIII. Disentangling Galactic dust emission and cosmic infrared background anisotropies
  • 2016
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 596
  • Journal article (peer-reviewed)abstract
    • Using the Planck 2015 data release (PR2) temperature maps, we separate Galactic thermal dust emission from cosmic infrared background (CIB) anisotropies. For this purpose, we implement a specifically tailored component-separation method, the so-called generalized needlet internal linear combination (GNILC) method, which uses spatial information (the angular power spectra) to disentangle the Galactic dust emission and CIB anisotropies. We produce significantly improved all-sky maps of Planck thermal dust emission, with reduced CIB contamination, at 353, 545, and 857 GHz. By reducing the CIB contamination of the thermal dust maps, we provide more accurate estimates of the local dust temperature and dust spectral index over the sky with reduced dispersion, especially at high Galactic latitudes above b = +/- 20 degrees. We find that the dust temperature is T = (19.4 +/- 1.3) K and the dust spectral index is beta = 1.6 +/- 0.1 averaged over the whole sky, while T = (19.4 +/- 1.5) K and beta = 1.6 +/- 0.2 on 21% of the sky at high latitudes. Moreover, subtracting the new CIB-removed thermal dust maps from the CMB-removed Planck maps gives access to the CIB anisotropies over 60% of the sky at Galactic latitudes vertical bar b vertical bar > 20 degrees. Because they are a significant improvement over previous Planck products, the GNILC maps are recommended for thermal dust science. The new CIB maps can be regarded as indirect tracers of the dark matter and they are recommended for exploring cross-correlations with lensing and large-scale structure optical surveys. The reconstructed GNILC thermal dust and CIB maps are delivered as Planck products.
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11.
  • Akrami, Y., et al. (author)
  • Planck 2018 results II. Low Frequency Instrument data processing
  • 2020
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 641
  • Journal article (peer-reviewed)abstract
    • We present a final description of the data-processing pipeline for the Planck Low Frequency Instrument (LFI), implemented for the 2018 data release. Several improvements have been made with respect to the previous release, especially in the calibration process and in the correction of instrumental features such as the effects of nonlinearity in the response of the analogue-to-digital converters. We provide a brief pedagogical introduction to the complete pipeline, as well as a detailed description of the important changes implemented. Self-consistency of the pipeline is demonstrated using dedicated simulations and null tests. We present the final version of the LFI full sky maps at 30, 44, and 70 GHz, both in temperature and polarization, together with a refined estimate of the solar dipole and a final assessment of the main LFI instrumental parameters.
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12.
  • Akrami, Y., et al. (author)
  • Planck intermediate results LII. Planet flux densities
  • 2017
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 607
  • Journal article (peer-reviewed)abstract
    • Measurements of flux density are described for five planets, Mars, Jupiter, Saturn, Uranus, and Neptune, across the six Planck High Frequency Instrument frequency bands (100-857 GHz) and these are then compared with models and existing data. In our analysis, we have also included estimates of the brightness of Jupiter and Saturn at the three frequencies of the Planck Low Frequency Instrument (30, 44, and 70 GHz). The results provide constraints on the intrinsic brightness and the brightness time-variability of these planets. The majority of the planet flux density estimates are limited by systematic errors, but still yield better than 1% measurements in many cases. Applying data from Planck HFI, the Wilkinson Microwave Anisotropy Probe (WMAP), and the Atacama Cosmology Telescope (ACT) to a model that incorporates contributions from Saturn's rings to the planet's total flux density suggests a best fit value for the spectral index of Saturn's ring system of beta(ring) = 2 : 30 +/- 0 : 03 over the 30-1000 GHz frequency range. Estimates of the polarization amplitude of the planets have also been made in the four bands that have polarization-sensitive detectors (100-353 GHz); this analysis provides a 95% confidence level upper limit on Mars's polarization of 1.8, 1.7, 1.2, and 1.7% at 100, 143, 217, and 353 GHz, respectively. The average ratio between the Planck-HFI measurements and the adopted model predictions for all five planets (excluding Jupiter observations for 353 GHz) is 1.004, 1.002, 1.021, and 1.033 for 100, 143, 217, and 353 GHz, respectively. Model predictions for planet thermodynamic temperatures are therefore consistent with the absolute calibration of Planck-HFI detectors at about the three-percent level. We compare our measurements with published results from recent cosmic microwave background experiments. In particular, we observe that the flux densities measured by Planck HFI and WMAP agree to within 2%. These results allow experiments operating in the mm-wavelength range to cross-calibrate against Planck and improve models of radiative transport used in planetary science.
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13.
  • Akrami, Y., et al. (author)
  • Planck intermediate results LIV. The Planck multi-frequency catalogue of non-thermal sources
  • 2018
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 619
  • Journal article (peer-reviewed)abstract
    • This paper presents the Planck Multi-frequency Catalogue of Non-thermal (i.e. synchrotron-dominated) Sources (PCNT) observed between 30 and 857 GHz by the ESA Planck mission. This catalogue was constructed by selecting objects detected in the full mission all-sky temperature maps at 30 and 143 GHz, with a signal-to-noise ratio (S/N) > 3 in at least one of the two channels after filtering with a particular Mexican hat wavelet. As a result, 29 400 source candidates were selected. Then, a multi-frequency analysis was performed using the Matrix Filters methodology at the position of these objects, and flux densities and errors were calculated for all of them in the nine Planck channels. This catalogue was built using a different methodology than the one adopted for the Planck Catalogue of Compact Sources (PCCS) and the Second Planck Catalogue of Compact Sources (PCCS2), although the initial detection was done with the same pipeline that was used to produce them. The present catalogue is the first unbiased, full-sky catalogue of synchrotron-dominated sources published at millimetre and submillimetre wavelengths and constitutes a powerful database for statistical studies of non-thermal extragalactic sources, whose emission is dominated by the central active galactic nucleus. Together with the full multi-frequency catalogue, we also define the Bright Planck Multi-frequency Catalogue of Non-thermal Sources (PCNTb), where only those objects with a S/N > 4 at both 30 and 143 GHz were selected. In this catalogue 1146 compact sources are detected outside the adopted Planck GAL070 mask; thus, these sources constitute a highly reliable sample of extragalactic radio sources. We also flag the high-significance subsample (PCNThs), a subset of 151 sources that are detected with S/N > 4 in all nine Planck channels, 75 of which are found outside the Planck mask adopted here. The remaining 76 sources inside the Galactic mask are very likely Galactic objects.
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14.
  • Darst, B. F., et al. (author)
  • Pathway-Specific Polygenic Risk Scores as Predictors of Amyloid-beta Deposition and Cognitive Function in a Sample at Increased Risk for Alzheimer's Disease
  • 2017
  • In: Journal of Alzheimers Disease. - : IOS Press. - 1387-2877 .- 1875-8908. ; 55:2, s. 473-484
  • Journal article (peer-reviewed)abstract
    • Polygenic risk scores (PRSs) have been used to combine the effects of variants with small effects identified by genome-wide association studies. We explore the potential for using pathway-specific PRSs as predictors of early changes in Alzheimer's disease (AD)-related biomarkers and cognitive function. Participants were from the Wisconsin Registry for Alzheimer's Prevention, a longitudinal study of adults who were cognitively asymptomatic at enrollment and enriched for a parental history of AD. Using genes associated with AD in the International Genomics of Alzheimer's Project's meta-analysis, we identified clusters of genes that grouped into pathways involved in amyloid-beta (A beta) deposition and neurodegeneration: A beta clearance, cholesterol metabolism, and immune response. Weighted pathway-specific and overall PRSs were developed and compared to APOE alone. Mixed models were used to assess whether each PRS was associated with cognition in 1,200 individuals, cerebral A beta deposition measured using amyloid ligand (Pittsburgh compound B) positron emission imaging in 168 individuals, and cerebrospinal fluid A beta deposition, neurodegeneration, and tau pathology in 111 individuals, with replication performed in an independent sample. We found that PRSs including APOE appeared to be driven by the inclusion of APOE, suggesting that the pathway-specific PRSs used here were not more predictive than an overall PRS or APOE alone. However, pathway-specific PRSs could prove to be useful as more knowledge is gained on the genetic variants involved in specific biological pathways of AD.
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15.
  • Ade, P. A. R., et al. (author)
  • A Constraint on Primordial B-modes from the First Flight of the Spider Balloon-borne Telescope
  • 2022
  • In: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 927:2
  • Journal article (peer-reviewed)abstract
    • We present the first linear polarization measurements from the 2015 long-duration balloon flight of SPIDER, which is an experiment that is designed to map the polarization of the cosmic microwave background (CMB) on degree angular scales. The results from these measurements include maps and angular power spectra from observations of 4.8% of the sky at 95 and 150 GHz, along with the results of internal consistency tests on these data. While the polarized CMB anisotropy from primordial density perturbations is the dominant signal in this region of sky, Galactic dust emission is also detected with high significance. Galactic synchrotron emission is found to be negligible in the SPIDER bands. We employ two independent foreground-removal techniques to explore the sensitivity of the cosmological result to the assumptions made by each. The primary method uses a dust template derived from Planck data to subtract the Galactic dust signal. A second approach, which constitutes a joint analysis of SPIDER and Planck data in the harmonic domain, assumes a modified-blackbody model for the spectral energy distribution of the dust with no constraint on its spatial morphology. Using a likelihood that jointly samples the template amplitude and r parameter space, we derive 95% upper limits on the primordial tensor-to-scalar ratio from Feldman-Cousins and Bayesian constructions, finding r < 0.11 and r < 0.19, respectively. Roughly half the uncertainty in r derives from noise associated with the template subtraction. New data at 280 GHz from SPIDER´s second flight will complement the Planck polarization maps, providing powerful measurements of the polarized Galactic dust emission.
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16.
  • Bergman, A. S., et al. (author)
  • 280 GHz Focal Plane Unit Design and Characterization for the SPIDER-2 Suborbital Polarimeter
  • 2018
  • In: Journal of Low Temperature Physics. - : Springer Science and Business Media LLC. - 0022-2291 .- 1573-7357. ; 193:5-6, s. 1075-1084
  • Journal article (peer-reviewed)abstract
    • We describe the construction and characterization of the 280 GHz bolometric focal plane units (FPUs) to be deployed on the second flight of the balloon-borne SPIDER instrument. These FPUs are vital to SPIDER's primary science goal of detecting or placing an upper limit on the amplitude of the primordial gravitational wave signature in the cosmic microwave background (CMB) by constraining the B-mode contamination in the CMB from Galactic dust emission. Each 280 GHz focal plane contains a 16 x 16 grid of corrugated silicon feedhorns coupled to an array of aluminum-manganese transition-edge sensor (TES) bolometers fabricated on 150 mm diameter substrates. In total, the three 280 GHz FPUs contain 1530 polarization-sensitive bolometers (765 spatial pixels) optimized for the low loading environment in flight and read out by time-division SQUID multiplexing. In this paper, we describe the mechanical, thermal, and magnetic shielding architecture of the focal planes and present cryogenic measurements which characterize yield and the uniformity of several bolometer parameters. The assembled FPUs have high yields, with one array as high as 95% including defects from wiring and readout. We demonstrate high uniformity in device parameters, finding the median saturation power for each TES array to be similar to 3 pW at 300 mK with a less than 6% variation across each array at 1 sigma. These focal planes will be deployed alongside the 95 and 150 GHz telescopes in the SPIDER-2 instrument, slated to fly from McMurdo Station in Antarctica in December 2018.
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17.
  • Filippini, J. P., et al. (author)
  • In-Flight Gain Monitoring of SPIDER's Transition-Edge Sensor Arrays
  • 2022
  • In: Journal of Low Temperature Physics. - : Springer Science and Business Media LLC. - 0022-2291 .- 1573-7357. ; 209:3-4, s. 649-657
  • Journal article (peer-reviewed)abstract
    • Experiments deploying large arrays of transition-edge sensors (TESs) often require a robust method to monitor gain variations with minimal loss of observing time. We propose a sensitive and non-intrusive method for monitoring variations in TES responsivity using small square waves applied to the TES bias. We construct an estimator for a TES's small-signal power response from its electrical response that is exact in the limit of strong electrothermal feedback. We discuss the application and validation of this method using flight data from SPIDER, a balloon-borne telescope that observes the polarization of the cosmic microwave background with more than 2000 TESs. This method may prove useful for future balloon- and space-based instruments, where observing time and ground control bandwidth are limited.
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18.
  • Gambrel, A. E., et al. (author)
  • The XFaster Power Spectrum and Likelihood Estimator for the Analysis of Cosmic Microwave Background Maps
  • 2021
  • In: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 922:2
  • Journal article (peer-reviewed)abstract
    • We present the XFaster analysis package, a fast, iterative angular power spectrum estimator based on a diagonal approximation to the quadratic Fisher matrix estimator. It uses Monte Carlo simulations to compute noise biases and filter transfer functions and is thus a hybrid of both Monte Carlo and quadratic estimator methods. In contrast to conventional pseudo-Cℓ–based methods, the algorithm described here requires a minimal number of simulations and does not require them to be precisely representative of the data to estimate accurate covariance matrices for the bandpowers. The formalism works with polarization-sensitive observations and also data sets with identical, partially overlapping, or independent survey regions. The method was first implemented for the analysis of BOOMERanG data and also used as part of the Planck analysis. Here we describe the full, publicly available analysis package, written in Python, as developed for the analysis of data from the 2015 flight of the Spider instrument. The package includes extensions for self-consistently estimating null spectra and estimating fits for Galactic foreground contributions. We show results from the extensive validation of XFaster using simulations and its application to the Spider data set.
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19.
  • Grote, V. A., et al. (author)
  • Inflammation marker and risk of pancreatic cancer: A nested case-control study within the EPIC cohort
  • 2012
  • In: British Journal of Cancer. - : Springer Science and Business Media LLC. - 0007-0920 .- 1532-1827. ; 106, s. 1866-1874
  • Journal article (peer-reviewed)abstract
    • Background: Established risk factors for pancreatic cancer include smoking, long-standing diabetes, high body fatness, and chronic pancreatitis, all of which can be characterised by aspects of inflammatory processes. However, prospective studies investigating the relation between inflammatory markers and pancreatic cancer risk are scarce. Methods: We conducted a nested case-control study within the European Prospective Investigation into Cancer and Nutrition, measuring prediagnostic blood levels of C-reactive protein (CRP), interleukin-6 (IL-6), and soluble receptors of tumour necrosis factor-α (sTNF-R1, R2) in 455 pancreatic cancer cases and 455 matched controls. Odds ratios (ORs) were estimated using conditional logistic regression models. Results: None of the inflammatory markers were significantly associated with risk of pancreatic cancer overall, although a borderline significant association was observed for higher circulating sTNF-R2 (crude OR=1.52 (95% confidence interval (CI) 0.97-2.39), highest vs lowest quartile). In women, however, higher sTNF-R1 levels were significantly associated with risk of pancreatic cancer (crude OR=1.97 (95% CI 1.02-3.79)). For sTNF-R2, risk associations seemed to be stronger for diabetic individuals and those with a higher BMI. Conclusion: Prospectively, CRP and IL-6 do not seem to have a role in our study with respect to risk of pancreatic cancer, whereas sTNF-R1 seemed to be a risk factor in women and sTNF-R2 might be a mediator in the risk relationship between overweight and diabetes with pancreatic cancer. Further large prospective studies are needed to clarify the role of proinflammatory proteins and cytokines in the pathogenesis of exocrine pancreatic cancer. © 2012 Cancer Research UK.
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20.
  • Gualtieri, R., et al. (author)
  • SPIDER : CMB Polarimetry from the Edge of Space
  • 2018
  • In: Journal of Low Temperature Physics. - : Springer Science and Business Media LLC. - 0022-2291 .- 1573-7357. ; 193:5-6, s. 1112-1121
  • Journal article (peer-reviewed)abstract
    • SPIDER is a balloon-borne instrument designed to map the polarization of the millimeter-wave sky at large angular scales. Spider targets the B-mode signature of primordial gravitational waves in the cosmic microwave background (CMB), with a focus on mapping a large sky area with high fidelity at multiple frequencies. SPIDER's first long-duration balloon (LDB) flight in January 2015 deployed a total of 2400 antenna-coupled transition-edge sensors (TESs) at 90 GHz and 150 GHz. In this work we review the design and in-flight performance of the SPIDER instrument, with a particular focus on the measured performance of the detectors and instrument in a space-like loading and radiation environment. SPIDER's second flight in December 2018 will incorporate payload upgrades and new receivers to map the sky at 285 GHz, providing valuable information for cleaning polarized dust emission from CMB maps.
  •  
21.
  • Leung, J. S.-Y., et al. (author)
  • A Simulation-based Method for Correcting Mode Coupling in CMB Angular Power Spectra
  • 2022
  • In: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 928:2
  • Journal article (peer-reviewed)abstract
    • Modern cosmic microwave background (CMB) analysis pipelines regularly employ complex time-domain filters, beam models, masking, and other techniques during the production of sky maps and their corresponding angular power spectra. However, these processes can generate couplings between multipoles from the same spectrum and from different spectra, in addition to the typical power attenuation. Within the context of pseudo-C-l based, MASTER-style analyses, the net effect of the time-domain filtering is commonly approximated by a multiplicative transfer function, F-l , that can fail to capture mode mixing and is dependent on the spectrum of the signal. To address these shortcomings, we have developed a simulation-based spectral correction approach that constructs a two-dimensional transfer matrix, J(ll'), which contains information about mode mixing in addition to mode attenuation. We demonstrate the application of this approach on data from the first flight of the Spider balloon-borne CMB experiment.
  •  
22.
  •  
23.
  • Dik, Vincent K., et al. (author)
  • Coffee and tea consumption, genotype- based CYP1A2 and NAT2 activity and colorectal cancer risk- Results from the EPIC cohort study
  • 2014
  • In: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 135:2, s. 401-412
  • Journal article (peer-reviewed)abstract
    • Coffee and tea contain numerous antimutagenic and antioxidant components and high levels of caffeine that may protect against colorectal cancer (CRC). We investigated the association between coffee and tea consumption and CRC risk and studied potential effect modification by CYP1A2 and NAT2 genotypes, enzymes involved in the metabolization of caffeine. Data from 477,071 participants (70.2% female) of the European Investigation into Cancer and Nutrition (EPIC) cohort study were analyzed. At baseline (1992-2000) habitual (total, caffeinated and decaffeinated) coffee and tea consumption was assessed with dietary questionnaires. Cox proportional hazards models were used to estimate adjusted hazard ratio's (HR) and 95% confidence intervals (95% CI). Potential effect modification by genotype-based CYP1A2 and NAT2 activity was studied in a nested case-control set of 1,252 cases and 2,175 controls. After a median follow-up of 11.6 years, 4,234 participants developed CRC (mean age 64.78.3 years). Total coffee consumption (high vs. non/low) was not associated with CRC risk (HR 1.06, 95% CI 0.95-1.18) or subsite cancers, and no significant associations were found for caffeinated (HR 1.10, 95% CI 0.97-1.26) and decaffeinated coffee (HR 0.96, 95% CI 0.84-1.11) and tea (HR 0.97, 95% CI 0.86-1.09). High coffee and tea consuming subjects with slow CYP1A2 or NAT2 activity had a similar CRC risk compared to non/low coffee and tea consuming subjects with a fast CYP1A2 or NAT2 activity, which suggests that caffeine metabolism does not affect the link between coffee and tea consumption and CRC risk. This study shows that coffee and tea consumption is not likely to be associated with overall CRC. What's new? Coffee and tea contain numerous compounds that may protect against colorectal cancer (CRC). In this study of more than 475,000 participants over more than a decade, the authors investigated whether coffee or tea consumption is associated with an altered risk of developing CRC. They also asked whether genetic variations in two enzymes involved in caffeine metabolism (CYP1A2 and NAT2) might affect this risk. They conclude that neither consumption patterns, nor genetic differences in caffeine metabolism, appear to have a significant impact on CRC risk.
  •  
24.
  • Nagy, J. M., et al. (author)
  • A New Limit on CMB Circular Polarization from SPIDER
  • 2017
  • In: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 844:2
  • Journal article (peer-reviewed)abstract
    • We present a new upper limit on cosmic microwave background (CMB) circular polarization from the 2015 flight of SPIDER, a balloon-borne telescope designed to search for B-mode linear polarization from cosmic inflation. Although the level of circular polarization in the CMB is predicted to be very small, experimental limits provide a valuable test of the underlying models. By exploiting the nonzero circular-to-linear polarization coupling of the half-wave plate polarization modulators, data from SPIDER's 2015 Antarctic flight provide a constraint on Stokes V at 95 and 150 GHz in the range 33 < l < 307. No other limits exist over this full range of angular scales, and SPIDER improves on the previous limit by several orders of magnitude, providing 95% C.L. constraints on l (l + 1)C-l(VV) /(2 pi) ranging from 141 to 255 mu K-2 at 150 GHz for a thermal CMB spectrum. As linear CMB polarization experiments become increasingly sensitive, the techniques described in this paper can be applied to obtain even stronger constraints on circular polarization.
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25.
  • Nitter, M., et al. (author)
  • Plasma methionine, choline, betaine, and dimethylglycine in relation to colorectal cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC)
  • 2014
  • In: Annals of Oncology. - : Elsevier BV. - 0923-7534 .- 1569-8041. ; 25:8, s. 1609-1615
  • Journal article (peer-reviewed)abstract
    • Background: Disturbances in one carbon metabolism may contribute to carcinogenesis by affecting methylation and synthesis of DNA. Choline and its oxidation product betaine are involved in this metabolism and can serve as alternative methyl group donors when folate status is low. Patients and methods: We conducted a case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC), to investigate plasma concentrations of the methyl donors methionine, choline, betaine (trimethylglycine), and dimethylglycine (DMG) in relation to colorectal cancer (CRC) risk. Our study included 1367 incident CRC cases (965 colon and 402 rectum) and 2323 controls matched by gender, age group, and study center. Multivariate-adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) for CRC risk were estimated by conditional logistic regression, comparing the fifth to the first quintile of plasma concentrations. Results: Overall, methionine (OR: 0.79, 95% CI: 0.63-0.99, P-trend = 0.05), choline (OR: 0.77, 95% CI: 0.60-0.99, P-trend = 0.07), and betaine (OR: 0.85, 95% CI: 0.66-1.09, P-trend = 0.06) concentrations were inversely associated with CRC risk of borderline significance. In participants with folate concentration below the median of 11.3 nmol/l, high betaine concentration was associated with reduced CRC risk (OR: 0.71, 95% CI: 0.50-1.00, P-trend = 0.02), which was not observed for those having a higher folate status. Among women, but not men, high choline concentration was associated with decreased CRC risk (OR: 0.62, 95% CI: 0.43-0.88, P-trend = 0.01). Plasma DMG was not associated with CRC risk. Conclusions: Individuals with high plasma concentrations of methionine, choline, and betaine may be at reduced risk of CRC.
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26.
  • Rohrmann, S., et al. (author)
  • Concentrations of IGF-I and IGFBP-3 and pancreatic cancer risk in the European Prospective Investigation into Cancer and Nutrition
  • 2012
  • In: British Journal of Cancer. - : Springer Science and Business Media LLC. - 0007-0920 .- 1532-1827. ; 106, s. 1004-1010
  • Journal article (peer-reviewed)abstract
    • Background: Insulin-like growth factors (IGFs) and their binding proteins (BPs) regulate cell differentiation, proliferation and apoptosis, and may have a role in the aetiology of various cancers. Information on their role in pancreatic cancer is limited and was examined here in a case-control study nested within the European Prospective Investigation into Cancer and Nutrition.Methods:Serum concentrations of IGF-I and IGFBP-3 were measured using enzyme-linked immunosorbent assays in 422 cases and 422 controls matched on age, sex, study centre, recruitment date, and time since last meal. Conditional logistic regression was used to compute odds ratios (OR) and 95% confidence intervals (CI) adjusted for confounding variables.Results:Neither circulating levels of IGF-I (OR=1.21, 95% CI 0.75-1.93 for top vs bottom quartile, P-trend 0.301), IGFBP-3 (O=R1.00, 95% CI 0.66-1.51, P-trend 0.79), nor the molar IGF-I/IGFBP-3 ratio, an indicator of free IGF-I level (OR=1.22, 95% CI 0.75-1.97, P-trend 0.27), were statistically significantly associated with the risk of pancreatic cancer. In a cross-classification, however, a high concentration of IGF-I with concurrently low levels of IGFBP-3 was related to an increased risk of pancreatic cancer (OR=1.72, 95% CI 1.05-2.83; P-interaction0.154). Conclusion: On the basis of these results, circulating levels of components of the IGF axis do not appear to be the risk factors for pancreatic cancer. However, on the basis of the results of a subanalysis, it cannot be excluded that a relatively large amount of IGF-1 together with very low levels of IGFBP-3 might still be associated with an increase in pancreatic cancer risk. © 2012 Cancer Research UK All rights reserved.
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27.
  • Sanchez, B. O., et al. (author)
  • SNIa Cosmology Analysis Results from Simulated LSST Images : From Difference Imaging to Constraints on Dark Energy
  • 2022
  • In: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 934:2
  • Journal article (peer-reviewed)abstract
    • The Vera Rubin Observatory Legacy Survey of Space and Time (LSST) is expected to process ∼106 transient detections per night. For precision measurements of cosmological parameters and rates, it is critical to understand the detection efficiency, magnitude limits, artifact contamination levels, and biases in the selection and photometry. Here we rigorously test the LSST Difference Image Analysis (DIA) pipeline using simulated images from the Rubin Observatory LSST Dark Energy Science Collaboration Data Challenge (DC2) simulation for the Wide-Fast-Deep survey area. DC2 is the first large-scale (300 deg2) image simulation of a transient survey that includes realistic cadence, variable observing conditions, and CCD image artifacts. We analyze ∼15 deg2 of DC2 over a 5 yr time span in which artificial point sources from Type Ia supernova (SNIa) light curves have been overlaid onto the images. The magnitude limits per filter are u = 23.66 mag, g = 24.69 mag, r = 24.06 mag, i = 23.45 mag, z = 22.54 mag, and y = 21.62 mag. The artifact contamination levels are ∼90% of all detections, corresponding to ∼1000 artifacts deg–2 in g band, and falling to 300 deg–2 in y band. The photometry has biases <1% for magnitudes 19.5 < m < 23. Our DIA performance on simulated images is similar to that of the Dark Energy Survey difference-imaging pipeline on real images. We also characterize DC2 image properties to produce catalog-level simulations needed for distance bias corrections. We find good agreement between DC2 data and simulations for distributions of signal-to-noise ratio, redshift, and fitted light-curve properties. Applying a realistic SNIa cosmology analysis for redshifts z < 1, we recover the input cosmology parameters to within statistical uncertainties.
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28.
  • Starks, E. J., et al. (author)
  • Insulin Resistance is Associated with Higher Cerebrospinal Fluid Tau Levels in Asymptomatic APOE epsilon 4 Carriers
  • 2015
  • In: Journal of Alzheimers Disease. - : IOS Press. - 1387-2877 .- 1875-8908. ; 46:2, s. 525-533
  • Journal article (peer-reviewed)abstract
    • Background: Insulin resistance (IR) is linked with the occurrence of pathological features observed in Alzheimer's disease (AD), including neurofibrillary tangles and amyloid plaques. However, the extent to which IR is associated with AD pathology in the cognitively asymptomatic stages of preclinical AD remains unclear. Objective: To determine the extent to which IR is linked with amyloid and tau pathology in late-middle-age. Method: Cerebrospinal fluid (CSF) samples collected from 113 participants enrolled in the Wisconsin Registry for Alzheimer's Prevention study (mean age = 60.6 years), were assayed for AD-related markers of interest: A beta(42), P-Tau(181), and T-Tau. IR was determined using the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR). Linear regression was used to test the effect of IR, and APOE epsilon 4, on tau and amyloid pathology. We hypothesized that greater IR would be associated with higher CSF P-Tau181 and T-Tau, and lower CSF A beta 42. Results: No significant main effects of HOMA-IR on P-Tau181, T-Tau, or A beta 42 were observed; however, significant interactions were observed between HOMA-IR and APOE epsilon 4 on CSF markers related to tau. Among APOE epsilon 4 carriers, higher HOMA-IR was associated with higher P-Tau181 and T-Tau. Among APOE epsilon 4 non-carriers, HOMA-IR was negatively associated with P-Tau181 and T-Tau. We found no effects of IR on A beta 42 levels in CSF. Conclusion: IR among asymptomatic APOE epsilon 4 carriers was associated with higher P-Tau(181) and T-Tau in late-middle age. The results suggest that IR may contribute to tau-related neurodegeneration in preclinical AD. The findings may have implications for developing prevention strategies aimed at modifying IR in mid-life.
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29.
  • Sund, Malin, et al. (author)
  • Plasma carotenoids, vitamin C, retinol and tocopherols levels and pancreatic cancer risk within the European Prospective Investigation into Cancer and Nutrition: A nested case-control study Plasma micronutrients and pancreatic cancer risk
  • 2015
  • In: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 136:6
  • Journal article (peer-reviewed)abstract
    • Evidence of a protective effect of several antioxidants and other nutrients on pancreatic cancer risk is inconsistent. The aim of this study was to investigate the association for prediagnostic plasma levels of carotenoids, vitamin C, retinol and tocopherols with risk of pancreatic cancer in a case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC). 446 incident exocrine pancreatic cancer cases were matched to 446 controls by age at blood collection, study center, sex, date and time of blood collection, fasting status and hormone use. Plasma carotenoids (- and -carotene, lycopene, -cryptoxanthin, canthaxanthin, zeaxanthin and lutein), - and -tocopherol and retinol were measured by reverse phase high-performance liquid chromatography and plasma vitamin C by a colorimetric assay. Incidence rate ratios (IRRs) with 95% confidence intervals (95%CIs) for pancreatic cancer risk were estimated using a conditional logistic regression analysis, adjusted for smoking status, smoking duration and intensity, waist circumference, cotinine levels and diabetes status. Inverse associations with pancreatic cancer risk were found for plasma -carotene (IRR highest vs. lowest quartile 0.52, 95%CI 0.31-0.88, p for trend=0.02), zeaxanthin (IRR highest vs. lowest quartile 0.53, 95%CI 0.30-0.94, p for trend=0.06) and -tocopherol (IRR highest vs. lowest quartile 0.62, 95%CI 0.39-0.99, p for trend=0.08. For - and -carotene, lutein, sum of carotenoids and -tocopherol, heterogeneity between geographical regions was observed. In conclusion, our results show that higher plasma concentrations of -carotene, zeaxanthin and -tocopherol may be inversely associated with risk of pancreatic cancer, but further studies are warranted. What's new? Fruits and vegetables may play a role in the prevention of pancreatic cancer, but associations between the antioxidants those foods contain and disease risk remain unclear. In this study, pancreatic cancer risk was inversely associated with increased prediagnostic plasma concentrations of the antioxidants -carotene, zeaxanthin, and -tocopherol. Geographic variations were also detected. In Northern European countries, inverse associations with risk were found for blood levels of several carotenoids, whereas the association was strongest for -tocopherol in Southern European countries. The role of carotenoids and vitamins should be considered in subsequent investigations of the etiology of pancreatic cancer.
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30.
  • Zamora-Ros, R., et al. (author)
  • Tea and coffee consumption and risk of esophageal cancer: The European prospective investigation into cancer and nutrition study
  • 2014
  • In: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 135:6, s. 1470-1479
  • Journal article (peer-reviewed)abstract
    • Epidemiological data regarding tea and coffee consumption and risk of esophageal cancer (EC) is still inconclusive. We examined the association of tea and coffee consumption with EC risk among 442,143 men and women without cancer at baseline from 9 countries of the European Prospective Investigation into Cancer and Nutrition. Tea and coffee intakes were recorded using country-specific validated dietary questionnaires. Cox regression models were used to analyze the relationships between tea and coffee intake and EC risk. During a mean follow-up of 11.1 years, 339 participants developed EC, of which 142 were esophageal adenocarcinoma (EAC) and 174 were esophageal squamous cell carcinoma (ESCC). In the multivariable models, no significant associations between tea (mostly black tea), and coffee intake and risk of EC, EAC and ESCC were observed. In stratified analyses, among men coffee consumption was inversely related to ESCC (HR for comparison of extreme tertiles 0.42, 95% CI 0.20-0.88; p-trend = 0.022), but not among women. In current smokers, a significant and inverse association was observed between ESCC risk and tea (HR 0.46, 95% CI 0.23-0.93; p-trend = 0.053) and coffee consumption (HR 0.37, 95% CI 0.19-0.73; p-trend = 0.011). However, no statistically significant findings were observed using the continuous variable (per 100 mL/d). These data did not show a significant association between tea and coffee consumption and EC, EAC and ESCC, although a decreased risk of ESCC among men and current smokers is suggested, but need to be confirmed in further prospective studies including more cases.
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31.
  • Aleksandrova, Krasimira, et al. (author)
  • Biomarker patterns of inflammatory and metabolic pathways are associated with risk of colorectal cancer : results from the European Prospective Investigation into Cancer and Nutrition (EPIC)
  • 2014
  • In: European Journal of Epidemiology. - : Springer Science and Business Media LLC. - 0393-2990 .- 1573-7284. ; 29:4, s. 261-275
  • Journal article (peer-reviewed)abstract
    • A number of biomarkers of inflammatory and metabolic pathways are individually related to higher risk of colorectal cancer (CRC); however, the association between biomarker patterns and CRC incidence has not been previously evaluated. Our study investigates the association of biomarker patterns with CRC in a prospective nested case-control study within the European Prospective Investigation into Cancer and Nutrition (EPIC). During median follow-up time of 7.0 (3.7-9.4) years, 1,260 incident CRC cases occurred and were matched to 1,260 controls using risk-set sampling. Pre-diagnostic measurements of C-peptide, glycated hemoglobin, triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), C-reactive protein (CRP), reactive oxygen metabolites (ROM), insulin-like growth factor 1, adiponectin, leptin and soluble leptin receptor (sOB-R) were used to derive biomarker patterns from principal component analysis (PCA). The relation with CRC incidence was assessed using conditional logistic regression models. We identified four biomarker patterns 'HDL-C/Adiponectin fractions', 'ROM/CRP', 'TG/C-peptide' and 'leptin/sOB-R' to explain 60 % of the overall biomarker variance. In multivariable-adjusted logistic regression, the 'HDL-C/Adiponectin fractions', 'ROM/CRP' and 'leptin/sOB-R' patterns were associated with CRC risk [for the highest quartile vs the lowest, incidence rate ratio (IRR) = 0.69, 95 % CI 0.51-0.93, P-trend = 0.01; IRR = 1.70, 95 % CI 1.30-2.23, P-trend = 0.002; and IRR = 0.79, 95 % CI 0.58-1.07; P-trend = 0.05, respectively]. In contrast, the 'TG/C-peptide' pattern was not associated with CRC risk (IRR = 0.75, 95 % CI 0.56-1.00, P-trend = 0.24). After cases within the first 2 follow-up years were excluded, the 'ROM/CRP' pattern was no longer associated with CRC risk, suggesting potential influence of preclinical disease on these associations. By application of PCA, the study identified 'HDL-C/Adiponectin fractions', 'ROM/CRP' and 'leptin/sOB-R' as biomarker patterns representing potentially important pathways for CRC development.
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32.
  • Aleksandrova, Krasimira, et al. (author)
  • Leptin and soluble leptin receptor in risk of colorectal cancer in the European prospective investigation into Cancer and nutrition cohort
  • 2012
  • In: Cancer Research. - Philadelphia, USA : American Association for Cancer Research. - 0008-5472 .- 1538-7445. ; 72:20, s. 5328-5337
  • Journal article (peer-reviewed)abstract
    • Leptin, a peptide hormone produced primarily by the adipocytes, is hypothesized to play a role in the pathogenesis of colorectal cancer (CRC). Soluble leptin receptor (sOB-R) may regulate leptin's physiologic functions; however its relation to CRC risk is unknown. This study explored the association of leptin and sOB-R with risk of CRC in a prospective nested case-control study within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. A total of 1,129 incident CRC cases (713 colon, 416 rectal) were matched within risk sets to 1,129 controls. Conditional logistic regression was used to calculate relative risks (RR) and 95% confidence intervals (CI). After multivariable adjustment including body mass index (BMI), waist circumference, and baseline leptin concentrations, sOB-R was strongly inversely associated with CRC (RR comparing the highest quintile vs. the lowest, 0.55; 95% CI, 0.40-0.76; P-trend = 0.0004) and colon cancer (RR, 0.42; 95% CI, 0.28-0.63, P-trend = 0.0001); whereas no association was seen for rectal cancer (RR adjusted for BMI and waist circumference, 0.83; 95% CI, 0.48-1.44, P-trend = 0.38). In contrast, leptin was not associated with risk of CRC (RR adjusted for BMI and waist circumference, 0.85; 95% CI, 0.56-1.29, P-trend = 0.23). Additional adjustments for circulating metabolic biomarkers did not attenuate these results. These novel findings suggest a strong inverse association between circulating sOB-R and CRC risk, independent of obesity measures, leptin concentrations, and other metabolic biomarkers. Further research is needed to confirm the potentially important role of sOB-R in CRC pathogenesis. Cancer Res; 72(20); 5328-37. (C) 2012 AACR.
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33.
  • Bamia, Christina, et al. (author)
  • Coffee, tea and decaffeinated coffee in relation to hepatocellular carcinoma in a European population: Multicentre, prospective cohort study
  • 2015
  • In: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 136, s. 1899-1908
  • Journal article (peer-reviewed)abstract
    • © 2014 UICC. Inverse associations of coffee and/or tea in relation to hepatocellular carcinoma (HCC) risk have been consistently identified in studies conducted mostly in Asia where consumption patterns of such beverages differ from Europe. In the European Prospective Investigation into Cancer and nutrition (EPIC), we identified 201 HCC cases among 486,799 men/women, after a median follow-up of 11 years. We calculated adjusted hazard ratios (HRs) for HCC incidence in relation to quintiles/categories of coffee/tea intakes. We found that increased coffee and tea intakes were consistently associated with lower HCC risk. The inverse associations were substantial, monotonic and statistically significant. Coffee consumers in the highest compared to the lowest quintile had lower HCC risk by 72% [HR: 0.28; 95% confidence intervals (CIs): 0.16-0.50, p-trend < 0.001]. The corresponding association of tea with HCC risk was 0.41 (95% CI: 0.22-0.78, p-trend50.003). There was no compelling evidence of heterogeneity of these associations across strata of important HCC risk factors, including hepatitis B or hepatitis C status (available in a nested case-control study). The inverse, monotonic associations of coffee intake with HCC were apparent for caffeinated (p-trend50.009), but not decaffeinated (p-trend50.45) coffee for which, however, data were available for a fraction of subjects. Results from this multicentre, European cohort study strengthen the existing evidence regarding the inverse association between coffee/tea and HCC risk. Given the apparent lack of heterogeneity of these associations by HCC risk factors and that coffee/tea are universal exposures, our results could have important implications for high HCC risk subjects.
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34.
  • Berman, Sara E, et al. (author)
  • Intracranial Arterial 4D Flow in Individuals with Mild Cognitive Impairment is Associated with Cognitive Performance and Amyloid Positivity.
  • 2017
  • In: Journal of Alzheimer's disease : JAD. - 1875-8908. ; 60:1, s. 243-252
  • Journal article (peer-reviewed)abstract
    • It is becoming increasingly recognized that cerebrovascular disease is a contributing factor in the pathogenesis of Alzheimer's disease (AD). A unique 4D-Flow magnetic resonance imaging (MRI) technique, phase contrast vastly undersampled isotropic projection imaging (PC VIPR), enables examination of angiographic and quantitative metrics of blood flow in the arteries of the Circle of Willis within a single MRI acquisition. Thirty-eight participants with mild cognitive impairment (MCI) underwent a comprehensive neuroimaging protocol (including 4D-Flow imaging) and a standard neuropsychological battery. A subset of participants (n=22) also underwent lumbar puncture and had cerebrospinal fluid (CSF) assayed for AD biomarkers. Cut-offs for biomarker positivity in CSF resulting from a receiver operating characteristic curve analysis of AD cases and controls from the larger Wisconsin Alzheimer's Disease Research Center cohort were used to classify MCI participants as biomarker positive or negative on amyloid-β (Aβ42), total-tau and total-tau/Aβ42 ratio. Internal carotid artery (ICA) and middle cerebral artery (MCA) mean flow were associated with executive functioning performance, with lower mean flow corresponding to worse performance. MCI participants who were biomarker positive for Aβ42 had lower ICA mean flow than did those who were Aβ42 negative. In sum, mean ICA and MCA arterial flow was associated with cognitive performance in participants with MCI and lower flow in the ICA was associated with amyloid positivity. This provides further evidence for vascular health as a contributing factor in the etiopathogenesis of AD, and could represent a point to intervene in the disease process.
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35.
  • Berman, Sara E, et al. (author)
  • Intracranial Arterial 4D-Flow is Associated with Metrics of Brain Health and Alzheimer's Disease.
  • 2015
  • In: Alzheimer's & dementia (Amsterdam, Netherlands). - : Wiley. - 2352-8729. ; 1:4, s. 420-428
  • Journal article (peer-reviewed)abstract
    • While cerebrovascular disease has long been known to co-occur with Alzheimer's disease (AD), recent studies suggest an etiologic contribution to AD pathogenesis. We used 4D-Flow magnetic resonance imaging (MRI) to evaluate blood flow and pulsatility indices in the Circle of Willis. We hypothesized decreased mean blood flow and increased pulsatility, metrics indicative of poor vascular health, would be associated with cerebral atrophy and an AD cerebrospinal fluid (CSF) profile.
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36.
  • Bidleman, Terry Frank, et al. (author)
  • Annual cycles of organochlorine pesticide enantiomers in Arctic air suggest changing sources and pathways
  • 2015
  • In: Atmospheric Chemistry And Physics. - : Copernicus GmbH. - 1680-7316 .- 1680-7324. ; 15:3, s. 1411-1420
  • Journal article (peer-reviewed)abstract
    • Air samples collected during 1994-2000 at the Canadian Arctic air monitoring station Alert (82 degrees 30'N, 62 degrees 20'W) were analysed by enantiospecific gas chromatography-mass spectrometry for alpha-hexachlorocyclohexane (alpha-HCH), trans-chlordane (TC) and cis-chlordane (CC). Results were expressed as enantiomer fractions (EF = peak areas of (+)/[(+) + (-)] enantiomers), where EFs = 0.5, <0.5 and >0.5 indicate racemic composition, and preferential depletion of (+) and (-) enantiomers, respectively. Long-term average EFs were close to racemic values for alpha-HCH (0.504 +/- 0.004, n = 197) and CC (0.505 +/- 0.004, n = 162), and deviated farther from racemic for TC (0.470 +/- 0.013, n = 165). Digital filtration analysis revealed annual cycles of lower alpha-HCH EFs in summer-fall and higher EFs in winter-spring. These cycles suggest volatilization of partially degraded alpha-HCH with EF < 0.5 from open water and advection to Alert during the warm season, and background transport of alpha-HCH with EF > 0.5 during the cold season. The contribution of sea-volatilized alpha-HCH was only 11% at Alert, vs. 32% at Resolute Bay (74.68 degrees N, 94.90 degrees W) in 1999. EFs of TC also followed annual cycles of lower and higher values in the warm and cold seasons. These were in phase with low and high cycles of the TC / CC ratio (expressed as F-TC = TC/(TC + CC)), which suggests greater contribution of microbially "weathered" TC in summer-fall versus winter-spring. CC was closer to racemic than TC and displayed seasonal cycles only in 1997-1998. EF profiles are likely to change with rising contribution of secondary emission sources, weathering of residues in the environment, and loss of ice cover in the Arctic. Enantiomer-specific analysis could provide added forensic capability to air monitoring programs.
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37.
  • Bidleman, Terry F., et al. (author)
  • Biannual cycles of organochlorine pesticide enantiomers in arctic air suggest changing sources and pathways
  • 2014
  • In: Atmospheric Chemistry and Physics Discussions. - : Copernicus GmbH. - 1680-7367 .- 1680-7375. ; 14:17, s. 25027-25050
  • Journal article (peer-reviewed)abstract
    • Air samples collected during 1994–2000 at the Canadian arctic air monitoring stationAlert (82300 N, 62200 W) were analyzed by enantiospecific gas chromatography –mass spectrometry for -hexachlorocyclohexane (-HCH), trans-chlordane (TC) and5 cis-chlordane (CC). Results were expressed as enantiomer fractions (EF = quantitiesof (+)/[(+)+(−)] enantiomers), where EFs=0.5, < 0.5 and > 0.5 indicate racemic composition,and preferential depletion of (+) and (−) enantiomers, respectively. Long-termaverage EFs were close to racemic values for -HCH (0.504±0.004, n =197) andCC (0.505±0.004, n =162), and deviated farther from racemic for TC (0.470±0.013,10 n =165). Digital filtration analysis revealed biannual cycles of lower -HCH EFs insummer-fall and higher EFs in winter-spring. These cycles suggest volatilization ofpartially degraded -HCH with EF < 0.5 from open water and advection to Alert duringthe warm season, and background transport of -HCH with EF> 0.5 during the coldseason. The contribution of sea-volatilized -HCH was only 11% at Alert, vs. 32%15 at Resolute Bay (74.68 N, 94.90W) in 1999. EFs of TC also followed biannual cyclesof lower and higher values in the warm and cold seasons. These were in phasewith low and high cycles of the TC/CC ratio (expressed as FTC =TC/(TC+CC)), whichsuggests greater contribution of microbially “weathered” TC in summer-fall vs. winterspring.CC was closer to racemic than TC and displayed seasonal cycles only in 1997–20 1998. EF profiles are likely to change with rising contribution of secondary emissionsources, weathering of residues in the environment, and loss of ice cover in the Arctic.Enantiomer-specific analysis could provide added forensic capability to air monitoringprograms.
  •  
38.
  • Calvert, Clara, et al. (author)
  • Changes in preterm birth and stillbirth during COVID-19 lockdowns in 26 countries
  • 2023
  • In: Nature Human Behaviour. - : Springer Nature. - 2397-3374. ; 7:4, s. 529-544
  • Journal article (peer-reviewed)abstract
    • Preterm birth (PTB) is the leading cause of infant mortality worldwide. Changes in PTB rates, ranging from -90% to +30%, were reported in many countries following early COVID-19 pandemic response measures ('lockdowns'). It is unclear whether this variation reflects real differences in lockdown impacts, or perhaps differences in stillbirth rates and/or study designs. Here we present interrupted time series and meta-analyses using harmonized data from 52 million births in 26 countries, 18 of which had representative population-based data, with overall PTB rates ranging from 6% to 12% and stillbirth ranging from 2.5 to 10.5 per 1,000 births. We show small reductions in PTB in the first (odds ratio 0.96, 95% confidence interval 0.95-0.98, P value <0.0001), second (0.96, 0.92-0.99, 0.03) and third (0.97, 0.94-1.00, 0.09) months of lockdown, but not in the fourth month of lockdown (0.99, 0.96-1.01, 0.34), although there were some between-country differences after the first month. For high-income countries in this study, we did not observe an association between lockdown and stillbirths in the second (1.00, 0.88-1.14, 0.98), third (0.99, 0.88-1.12, 0.89) and fourth (1.01, 0.87-1.18, 0.86) months of lockdown, although we have imprecise estimates due to stillbirths being a relatively rare event. We did, however, find evidence of increased risk of stillbirth in the first month of lockdown in high-income countries (1.14, 1.02-1.29, 0.02) and, in Brazil, we found evidence for an association between lockdown and stillbirth in the second (1.09, 1.03-1.15, 0.002), third (1.10, 1.03-1.17, 0.003) and fourth (1.12, 1.05-1.19, <0.001) months of lockdown. With an estimated 14.8 million PTB annually worldwide, the modest reductions observed during early pandemic lockdowns translate into large numbers of PTB averted globally and warrant further research into causal pathways.
  •  
39.
  • Campa, Daniele, et al. (author)
  • Leukocyte telomere length in relation to pancreatic cancer risk: a prospective study.
  • 2014
  • In: Cancer Epidemiology Biomarkers & Prevention. - 1538-7755 .- 1055-9965. ; 23:11, s. 2447-2454
  • Journal article (peer-reviewed)abstract
    • Background: Several studies have examined leukocyte telomere length (LTL) as a possible predictor for cancer at various organ sites. The hypothesis originally motivating many of these studies was that shorter telomeres would be associated with an increase in cancer risk, the results of epidemiologic studies have been inconsistent, however, and suggested positive, negative, or null associations. Two studies have addressed the association of LTL in relation to pancreatic cancer risk and the results are contrasting. Methods: we measured LTL in a prospective study of 331 pancreatic cancer cases and 331 controls in the context of the European Prospective Investigation into Cancer and Nutrition (EPIC). Results: We observed that the mean LTL was higher in cases (0.59±0.20) than in controls (0.57±0.17), although this difference was not statistically significant (p=0.07), and a basic logistic regression model showed no association of LTL with pancreas cancer risk. When adjusting for levels of HbA1c and C-Peptide, however, there was a weakly positive association between longer LTL and pancreatic cancer risk , OR=1.13 (1.01-1.27). Additional analyses by cubic spline regression suggested a possible non-linear relationship between RTL and pancreatic cancer risk (P=0.022), with a statistically non-significant increase in risk at very low LTL, as well as a significant increase at high LTL. Conclusion: Taken together, the results from our study do not support LTL as a uniform and strong predictor of pancreatic cancer. Impact: The results of this manuscript can provide insights into telomere dynamics and highlight the complex relationship between LTL and pancreatic cancer risk.
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40.
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41.
  • Duarte-Salles, T., et al. (author)
  • Dairy products and risk of hepatocellular carcinoma: The European Prospective Investigation into Cancer and Nutrition
  • 2014
  • In: International Journal of Cancer. - : Wiley-Liss Inc.. - 0020-7136 .- 1097-0215. ; 135:7, s. 1662-1672
  • Journal article (peer-reviewed)abstract
    • Intake of dairy products has been associated with risk of some cancers, but findings are often inconsistent and information on hepatocellular carcinoma (HCC) risk is limited, particularly from prospective settings. The aim of our study was to investigate the association between consumption of total and specific dairy products (milk/cheese/yogurt) and their components (calcium/vitamin D/fats/protein), with first incident HCC (Ncases = 191) in the European Prospective Investigation into Cancer and Nutrition cohort, including a nested case-control subset (Ncases = 122) with the assessment of hepatitis B virus/hepatitis C virus infections status, liver damage and circulating insulin-like growth factor (IGF)-I levels. For cohort analyses, multivariable-adjusted Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (95% CI). For nested case-control analyses, conditional logistic regression was used to calculate odds ratios and 95% CI. A total of 477,206 participants were followed-up for an average of 11 years (person-years follow-up = 5,415,385). In the cohort study, a significant positive HCC risk association was observed for total dairy products (highest vs. lowest tertile, HR = 1.66, 95% CI: 1.13-2.43; ptrend = 0.012), milk (HR = 1.51, 95% CI: 1.02-2.24; ptrend = 0.049), and cheese (HR = 1.56, 95% CI: 1.02-2.38; ptrend = 0.101), but not yogurt (HR = 0.94, 95% CI: 0.65-1.35). Dietary calcium, vitamin D, fat and protein from dairy sources were associated with increased HCC risk, whereas the same nutrients from nondairy sources showed inverse or null associations. In the nested case-control study, similar results were observed among hepatitis-free individuals. Results from this large prospective cohort study suggest that higher consumption of dairy products, particularly milk and cheese, may be associated with increased HCC risk. Validation of these findings in other populations is necessary. Potential biologic mechanisms require further exploration. What's New? Currently, the role of dairy product intake in the development of hepatocellular carcinoma (HCC) is unclear. Using detailed data from a large multi-centric prospective cohort, this study investigated the association between consumption of total and specific dairy products with first incident HCC. The study found that higher dairy product consumption, particularly milk and cheese, was associated with increased HCC risk. Dietary calcium, vitamin D, fat and protein did not explain the observed associations. However, higher circulating IGF-I levels may play a role. © 2014 UICC.
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42.
  • Duell, E. J., et al. (author)
  • Variation at ABO histo-blood group and FUT loci and diffuse and intestinal gastric cancer risk in a European population
  • 2015
  • In: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 136:4, s. 880-893
  • Journal article (peer-reviewed)abstract
    • ABO blood serotype A is known to be associated with risk of gastric cancer (GC), but little is known how ABO alleles and the fucosyltransferase (FUT) enzymes and genes which are involved in Lewis antigen formation [and in Helicobacter pylori (H. pylori) binding and pathogenicity] may be related to GC risk in a European population. The authors conducted an investigation of 32 variants at ABO and FUT1-7 loci and GC risk in a case-control study of 365 cases and 1,284 controls nested within the EPIC cohort (the EPIC-Eurgast study). Four variants (including rs505922) in ABO, and allelic blood group A (AO+AA, odds ratio=1.84, 95%CI=1.20-2.80) were associated with diffuse-type GC; however, conditional models with other ABO variants indicated that the associations were largely due to allelic blood group A. One variant in FUT5 was also associated with diffuse-type GC, and four variants (and haplotypes) in FUT2 (Se), FUT3 (Le) and FUT6 with intestinal-type GC. Further, one variant in ABO, two in FUT3 and two in FUT6 were associated with H. pylori infection status in controls, and two of these (in FUT3 and FUT6) were weakly associated with intestinal-type GC risk. None of the individual variants surpassed a Bonferroni corrected p-value cutoff of 0.0016; however, after a gene-based permutation test, two loci [FUT3(Le)/FUT5/FUT6 and FUT2(Se)] were significantly associated with diffuse- and intestinal-type GC, respectively. Replication and functional studies are therefore recommended to clarify the role of ABO and FUT alleles in H. pylori infection and subtype-specific gastric carcinogenesis. What's New? Blood type A indicates a higher risk of gastric cancer, but why? This study examined the relationship between blood group genes and cancer. The authors investigated 32 variants among not only the ABO alleles, but also including the genes involved in producing the Lewis blood group antigens. They confirmed blood group A as a risk factor for diffuse-type gastric cancer, and also detected an association between certain Lewis antigen alleles and intestinal-type gastric cancer. Interestingly, these alleles also popped up among controls who harbored H. pylori infection. These associations certainly warrant further investigation into their role in gastric cancer.
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43.
  • Espinosa-Parrilla, Yolanda, et al. (author)
  • Genetic association of gastric cancer with miRNA clusters including the cancer-related genes MIR29, MIR25, MIR93 and MIR106: Results from the EPIC-EURGAST study
  • 2014
  • In: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 135:9, s. 2065-2076
  • Journal article (peer-reviewed)abstract
    • MicroRNAs (miRNAs) are post-transcriptional gene regulators involved in a wide range of biological processes including tumorigenesis. Deregulation of miRNA pathways has been associated with cancer but the contribution of their genetic variability to this disorder is poorly known. We analyzed the genetic association of gastric cancer (GC) and its anatomical and histological subtypes, with 133 single-nucleotide polymorphisms (SNPs) tagging 15 isolated miRNAs and 24 miRNA clusters potentially involved in cancer, in 365 GC cases and 1,284 matched controls within the European Prospective Investigation into Cancer and Nutrition cohort. Various SNPs were associated with GC under the log-additive model. Furthermore, several of these miRNAs passed the gene-based permutation test when analyzed according to GC subtypes: three tagSNPs of the miR-29a/miR-29b-1 cluster were associated with diffuse subtype (minimum p-value=1.7 x 10(-4); odds ratio, OR=1.72; 95% confidence interval, CI=1.30-2.28), two tagSNPs of the miR-25/miR-93/miR-106b cluster were associated with cardia GC (minimum p-value=5.38 x 10(-3); OR=0.56, 95% CI=0.37-0.86) and one tagSNP of the miR-363/miR-92a-2/miR-19b-2/miR-20b/miR-18b/miR-106a cluster was associated with noncardia GC (minimum p-value=5.40 x 10(-3); OR=1.41, 95% CI=1.12-1.78). Some functionally validated target genes of these miRNAs are implicated in cancer-related processes such as methylation (DNMT3A, DNMT3B), cell cycle (E2F1, CDKN1A, CDKN1C), apoptosis (BCL2L11, MCL1), angiogenesis (VEGFA) and progression (PIK3R1, MYCN). Furthermore, we identified genetic interactions between variants tagging these miRNAs and variants in their validated target genes. Deregulation of the expression of these miRNAs in GC also supports our findings, altogether suggesting for the fist time that genetic variation in MIR29, MIR25, MIR93 and MIR106b may have a critical role in genetic susceptibility to GC and could contribute to the molecular mechanisms of gastric carcinogenesis.
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44.
  • Fedirko, V., et al. (author)
  • Glycemic index, glycemic load, dietary carbohydrate, and dietary fiber intake and risk of liver and biliary tract cancers in Western Europeans
  • 2013
  • In: Annals of Oncology. - : Elsevier BV. - 0923-7534 .- 1569-8041. ; 24:2, s. 543-553
  • Journal article (peer-reviewed)abstract
    • Background: The type and quantity of dietary carbohydrate as quantified by glycemic index (GI) and glycemic load (GL), and dietary fiber may influence the risk of liver and biliary tract cancers, but convincing evidence is lacking. Patients and methods: The association between dietary GI/GL and carbohydrate intake with hepatocellular carcinoma (HCC; N = 191), intrahepatic bile duct (IBD; N = 66), and biliary tract (N = 236) cancer risk was investigated in 477 206 participants of the European Prospective Investigation into Cancer and Nutrition cohort. Dietary intake was assessed by country-specific, validated dietary questionnaires. Hazard ratios and 95% confidence intervals were estimated from proportional hazard models. HBV/HCV status was measured in a nested case-control subset. Results: Higher dietary GI, GL, or increased intake of total carbohydrate was not associated with liver or biliary tract cancer risk. For HCC, divergent risk estimates were observed for total sugar = 1.43 (1.17-1.74) per 50 g/day, total starch = 0.70 (0.55-0.90) per 50 g/day, and total dietary fiber = 0.70 (0.52-0.93) per 10 g/day. The findings for dietary fiber were confirmed among HBV/HCV-free participants [0.48 (0.23-1.01)]. Similar associations were observed for IBD [dietary fiber = 0.59 (0.37-0.99) per 10 g/day], but not biliary tract cancer. Conclusions: Findings suggest that higher consumption of dietary fiber and lower consumption of total sugars are associated with lower HCC risk. In addition, high dietary fiber intake could be associated with lower IBD cancer risk. © The Author 2012. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved.
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45.
  • Fedirko, Veronika, et al. (author)
  • Prediagnostic 25-Hydroxyvitamin D, VDR and CASR polymorphisms, and survival in patients with colorectal cancer in Western European populations
  • 2012
  • In: Cancer Epidemiology, Biomarkers and Prevention. - 1055-9965 .- 1538-7755. ; 21:4, s. 582-593
  • Journal article (peer-reviewed)abstract
    • Background: Individuals with higher blood 25-hydroxyvitamin D [25(OH)D] levels have a lower risk of developing colorectal cancer (CRC), but the influence of 25(OH)D on mortality after CRC diagnosis is unknown.Methods: The association between prediagnostic 25(OH)D levels and CRC-specific (N ¼ 444) and overall mortality (N ¼ 541) was prospectively examined among 1,202 participants diagnosed with CRC between 1992 and 2003 in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort.Multivariable Cox proportional hazards models were used to calculate HRs and corresponding 95% CIs according to 25(OH)D quintiles and genetic variation within the VDR and CASR genes. Potential dietary, lifestyle, and metabolic effect modifiers were also investigated.Results: There were 541 deaths, 444 (82%) due to CRC. Mean follow-up was 73 months. In multivariable analysis, higher 25(OH)D levels were associated with a statistically significant reduction in CRC-specific (Ptrend ¼ 0.04) and overall mortality (Ptrend ¼ 0.01). Participants with 25(OH)D levels in the highest quintile had an adjusted HR of 0.69 (95% CI: 0.50–0.93) for CRC-specific mortality and 0.67 (95% CI: 0.50–0.88) for overall mortality, compared with the lowest quintile. Except for a possible interaction by prediagnostic dietary calcium intake (Pinteraction ¼ 0.01), no other potential modifying factors related to CRC survival were noted. The VDR (FokI and BsmI) and CASR (rs1801725) genotypes were not associated with survival.Conclusions: High prediagnostic 25(OH)D levels are associated with improved survival of patients with CRC. Impact: Our findings may stimulate further research directed at investigating the effects of blood vitamin D levels before, at, and after CRC diagnosis on outcomes in CRC patients.
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46.
  • Hughes, David J, et al. (author)
  • Selenium status is associated with colorectal cancer risk in the European prospective investigation of cancer and nutrition cohort.
  • 2015
  • In: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 136:5, s. 1149-1161
  • Journal article (peer-reviewed)abstract
    • Suboptimal intakes of the micronutrient selenium (Se) are found in many parts of Europe. Low Se status may contribute to colorectal cancer (CRC) development. We assessed Se status by measuring serum levels of Se and Selenoprotein P (SePP) and examined the association with CRC risk in a nested case-control design (966 CRC cases; 966 matched controls) within the European Prospective Investigation into Cancer and Nutrition. Se was measured by total reflection X-ray fluorescence and SePP by immunoluminometric sandwich assay. Multivariable incidence rate ratios (IRRs) and 95% confidence intervals (CIs) were calculated using conditional logistic regression. Respective mean Se and SePP levels were 84.0 μg/L and 4.3 mg/L in cases and 85.6 μg/L and 4.4 mg/L in controls. Higher Se concentrations were associated with a non-significant lower CRC risk (IRR = 0.92, 95% CI: 0.82-1.03 per 25 μg/L increase). However, sub-group analyses by sex showed a statistically significant association for women (ptrend  = 0.032; per 25 μg/L Se increase, IRR = 0.83, 95% CI: 0.70-0.97) but not for men. Higher SePP concentrations were inversely associated with CRC risk (ptrend  = 0.009; per 0.806 mg/L increase, IRR = 0.89, 95% CI: 0.82-0.98) with the association more apparent in women (ptrend  = 0.004; IRR = 0.82, 95% CI: 0.72-0.94 per 0.806 mg/L increase) than men (ptrend  = 0.485; IRR = 0.98, 95% CI: 0.86-1.12 per 0.806 mg/L increase). The findings indicate that Se status is suboptimal in many Europeans and suggest an inverse association between CRC risk and higher serum Se status, which is more evident in women.
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47.
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48.
  • Jakszyn, P., et al. (author)
  • Meat and heme iron intake and esophageal adenocarcinoma in the European Prospective Investigation into Cancer and Nutrition study
  • 2013
  • In: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 133:11, s. 2744-2750
  • Journal article (peer-reviewed)abstract
    • Although recent studies suggest that high intakes of meat and heme iron are risk factors for several types of cancer, studies in relation to esophageal adenocarcinoma (EAC) are scarce. Previous results in the European Prospective Investigation into Cancer and Nutrition (EPIC) based on a relatively small number of cases suggested a positive association between processed meat and EAC. In this study, we investigate the association between intake of different types of meats and heme iron intake and EAC risk in a larger number of cases from EPIC. The study included 481,419 individuals and 137 incident cases of EAC that occurred during an average of 11 years of follow-up. Dietary intake of meat (unprocessed/processed red and white meat) was assessed by validated center-specific questionnaires. Heme iron was calculated as a type-specific percentage of the total iron content in meat. After adjusting for relevant confounders, we observed a statistically significant positive association of EAC risk with heme iron and processed meat intake, with HR: 1.67, 95% CI: 1.05-2.68 and HR: 2.27, 95% CI:1.33-3.89, respectively, for comparison of the highest vs. lowest tertile of intake. Our results suggest a potential association between higher intakes of processed meat and heme iron and risk of EAC.
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49.
  • KC, Ashish, 1982-, et al. (author)
  • Changes in preterm birth and stillbirth during COVID-19 lockdowns in 26 countries.
  • 2023
  • In: Nature human behaviour. - : Springer Science and Business Media LLC. - 2397-3374. ; 7:4, s. 529-544
  • Journal article (peer-reviewed)abstract
    • Preterm birth (PTB) is the leading cause of infant mortality worldwide. Changes in PTB rates, ranging from -90% to +30%, were reported in many countries following early COVID-19 pandemic response measures ('lockdowns'). It is unclear whether this variation reflects real differences in lockdown impacts, or perhaps differences in stillbirth rates and/or study designs. Here we present interrupted time series and meta-analyses using harmonized data from 52 million births in 26 countries, 18 of which had representative population-based data, with overall PTB rates ranging from 6% to 12% and stillbirth ranging from 2.5 to 10.5 per 1,000 births. We show small reductions in PTB in the first (odds ratio 0.96, 95% confidence interval 0.95-0.98, P value <0.0001), second (0.96, 0.92-0.99, 0.03) and third (0.97, 0.94-1.00, 0.09) months of lockdown, but not in the fourth month of lockdown (0.99, 0.96-1.01, 0.34), although there were some between-country differences after the first month. For high-income countries in this study, we did not observe an association between lockdown and stillbirths in the second (1.00, 0.88-1.14, 0.98), third (0.99, 0.88-1.12, 0.89) and fourth (1.01, 0.87-1.18, 0.86) months of lockdown, although we have imprecise estimates due to stillbirths being a relatively rare event. We did, however, find evidence of increased risk of stillbirth in the first month of lockdown in high-income countries (1.14, 1.02-1.29, 0.02) and, in Brazil, we found evidence for an association between lockdown and stillbirth in the second (1.09, 1.03-1.15, 0.002), third (1.10, 1.03-1.17, 0.003) and fourth (1.12, 1.05-1.19, <0.001) months of lockdown. With an estimated 14.8 million PTB annually worldwide, the modest reductions observed during early pandemic lockdowns translate into large numbers of PTB averted globally and warrant further research into causal pathways.
  •  
50.
  • Kim, Won Hwa, et al. (author)
  • Cerebrospinal fluid biomarkers of neurofibrillary tangles and synaptic dysfunction are associated with longitudinal decline in white matter connectivity: A multi-resolution graph analysis.
  • 2019
  • In: NeuroImage. Clinical. - : Elsevier BV. - 2213-1582. ; 21
  • Journal article (peer-reviewed)abstract
    • In addition to the development of beta amyloid plaques and neurofibrillary tangles, Alzheimer's disease (AD) involves the loss of connecting structures including degeneration of myelinated axons and synaptic connections. However, the extent to which white matter tracts change longitudinally, particularly in the asymptomatic, preclinical stage of AD, remains poorly characterized. In this study we used a novel graph wavelet algorithm to determine the extent to which microstructural brain changes evolve in concert with the development of AD neuropathology as observed using CSF biomarkers. A total of 118 participants with at least two diffusion tensor imaging (DTI) scans and one lumbar puncture for CSF were selected from two observational and longitudinally followed cohorts. CSF was assayed for pathology specific to AD (Aβ42 and phosphorylated-tau), neurodegeneration (total-tau), axonal degeneration (neurofilament light chain protein; NFL), and synaptic degeneration (neurogranin). Tractography was performed on DTI scans to obtain structural connectivity networks with 160 nodes where the nodes correspond to specific brain regions of interest (ROIs) and their connections were defined by DTI metrics (i.e., fractional anisotropy (FA) and mean diffusivity (MD)). For the analysis, we adopted a multi-resolution graph wavelet technique called Wavelet Connectivity Signature (WaCS) which derives higher order representations from DTI metrics at each brain connection. Our statistical analysis showed interactions between the CSF measures and the MRI time interval, such that elevated CSF biomarkers and longer time were associated with greater longitudinal changes in white matter microstructure (decreasing FA and increasing MD). Specifically, we detected a total of 17 fiber tracts whose WaCS representations showed an association between longitudinal decline in white matter microstructure and both CSF p-tau and neurogranin. While development of neurofibrillary tangles and synaptic degeneration are cortical phenomena, the results show that they are also associated with degeneration of underlying white matter tracts, a process which may eventually play a role in the development of cognitive decline and dementia.
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