Image resampling and discretization effect on the estimate of myocardial radiomic features from T1 and T2 mapping in hypertrophic cardiomyopathy

Radiomics is emerging as a promising and useful tool in cardiac magnetic resonance (CMR) imaging applications. Accordingly, the purpose of this study was to investigate, for the first time, the effect of image resampling/discretization and filtering on radiomic features estimation from quantitative CMR T1 and T2 mapping. Specifically, T1 and T2 maps of 26 patients with hypertrophic cardiomyopathy (HCM) were used to estimate 98 radiomic features for 7 different resampling voxel sizes (at fixed bin width), 9 different bin widths (at fixed resampling voxel size), and 7 different spatial filters (at fixed resampling voxel size/bin width). While we found a remarkable dependence of myocardial radiomic features from T1 and T2 mapping on image filters, many radiomic features showed a limited sensitivity to resampling voxel size/bin width, in terms of intraclass correlation coefficient (> 0.75) and coefficient of variation (< 30%). The estimate of most textural radiomic features showed a linear significant (p < 0.05) correlation with resampling voxel size/bin width. Overall, radiomic features from T2 maps have proven to be less sensitive to image preprocessing than those from T1 maps, especially when varying bin width. Our results might corroborate the potential of radiomics from T1/T2 mapping in HCM and hopefully in other myocardial diseases

The effect of statin therapy on heart failure events: a collaborative meta-analysis of unpublished data from major randomized trials

The effect of statins on risk of heart failure (HF) hospitalization and HF death remains uncertain. We aimed to establish whether statins reduce major HF events.We searched Medline, EMBASE, and the Cochrane Central Register of Controlled Trials for randomized controlled endpoint statin trials from 1994 to 2014. Collaborating trialists provided unpublished data from adverse event reports. We included primary- and secondary-prevention statin trials with >1000 participants followed for >1 year. Outcomes consisted of first non-fatal HF hospitalization, HF death and a composite of first non-fatal HF hospitalization or HF death. HF events occurring <30 days after within-trial myocardial infarction (MI) were excluded. We calculated risk ratios (RR) with fixed-effects meta-analyses. In up to 17 trials with 132 538 participants conducted over 4.3 [weighted standard deviation (SD) 1.4] years, statin therapy reduced LDL-cholesterol by 0.97 mmol/L (weighted SD 0.38 mmol/L). Statins reduced the numbers of patients experiencing non-fatal HF hospitalization (1344/66 238 vs. 1498/66 330; RR 0.90, 95% confidence interval, CI 0.84-0.97) and the composite HF outcome (1234/57 734 vs. 1344/57 836; RR 0.92, 95% CI 0.85-0.99) but not HF death (213/57 734 vs. 220/57 836; RR 0.97, 95% CI 0.80-1.17). The effect of statins on first non-fatal HF hospitalization was similar whether this was preceded by MI (RR 0.87, 95% CI 0.68-1.11) or not (RR 0.91, 95% CI 0.84-0.98).In primary- and secondary-prevention trials, statins modestly reduced the risks of non-fatal HF hospitalization and a composite of non-fatal HF hospitalization and HF death with no demonstrable difference in risk reduction between those who suffered an MI or not

Evidence of selection for effective nodulation in the Trifolium spp. symbiosis with Rhizobium leguminosarum biovar trifolii

The pasture-breeding program to improve production in the natural grasslands in Uruguay has acknowledged that indigenous Rhizobium strains are incompatible with introduced Mediterranean clovers. In an attempt to understand and overcome this problem, a cross-row experiment was set up in 1999 in a basaltic, acid soil in Glencoe, Uruguay, to follow the survival and performance of 9 exotic strains of Rhizobium leguminosarum bv. trifolii. This paper reports on the ability of the introduced strains to compete for nodule occupancy of Mediterranean clover hosts and impacts of the introduced strains on the productivity of the indigenous Uruguayan clover Trifolium polymorphum. Strain WSM1325 was a superior inoculant and remained highly persistent and competitive for the effective symbiosis with the Mediterranean hosts, T. purpureum and T. repens, in the Uruguayan environment in the third year of the experiment. The Mediterranean hosts (T. purpureum and T. repens) nodulated with the introduced strains but did not nodulate with any indigenous R. leguminosarum bv. trifolii typed from nodules of T. polymorphum. Conversely, there were no nodules on the Uruguayan host T. polymorphum that contained introduced R. leguminosarum bv. trifolii. These results reveal the establishment of effective symbioses between strains of R. leguminosarum bv. trifolii and clover even though the soil contained ineffective R. leguminosarum bv. trifolii for all hosts. We believe our results are the first reported example of ‘selective’ nodulation for an effective symbiosis in situ with annual and perennial clovers in acid soils

A comprehensive assessment of physical image quality of five different scanners for head CT imaging as clinically used at a single hospital centre—A phantom study

Nowadays, given the technological advance in CT imaging and increasing heterogeneity in characteristics of CT scanners, a number of CT scanners with different manufacturers/technologies are often installed in a hospital centre and used by various departments. In this phantom study, a comprehensive assessment of image quality of 5 scanners (from 3 manufacturers and with different models) for head CT imaging, as clinically used at a single hospital centre, was hence carried out. Helical and/or sequential acquisitions of the Catphan-504 phantom were performed, using the scanning protocols (CTDIvol range: 54.7–57.5 mGy) employed by the staff of various Radiology/Neuroradiology departments of our institution for routine head examinations. CT image quality for each scanner/acquisition protocol was assessed through noise level, noise power spectrum (NPS), contrast-to-noise ratio (CNR), modulation transfer function (MTF), low contrast detectability (LCD) and non-uniformity index analyses. Noise values ranged from 3.5 HU to 5.7 HU across scanners/acquisition protocols. NPS curves differed in terms of peak position (range: 0.21–0.30 mm-1). A substantial variation of CNR values with scanner/acquisition protocol was observed for different contrast inserts. The coefficient of variation (standard deviation divided by mean value) of CNR values across scanners/acquisition protocols was 18.3%, 31.4%, 34.2%, 30.4% and 30% for teflon, delrin, LDPE, polystyrene and acrylic insert, respectively. An appreciable difference in MTF curves across scanners/acquisition protocols was revealed, with a coefficient of variation of f50%/f10% of MTF curves across scanners/acquisition protocols of 10.1%/ 7.4%. A relevant difference in LCD performance of different scanners/acquisition protocols was found. The range of contrast threshold for a typical object size of 3 mm was 3.7–5.8 HU. Moreover, appreciable differences in terms of NUI values (range: 4.1%-8.3%) were found. The analysis of several quality indices showed a non-negligible variability in head CT imaging capabilities across different scanners/acquisition protocols. This highlights the importance of a physical in-depth characterization of image quality for each CT scanner as clinically used, in order to optimize CT imaging procedures

Diet and gallstones in Italy: the cross-sectional MICOL results.

Fifteen thousand nine hundred ten men and 13,674 women (age, 30-69 years) were enrolled in an epidemiological survey of the general population, between December 1984 and April 1987. Each participant was submitted to ultrasonography (US) of the gallbladder and completed a food-frequency questionnaire, covering 38 food items. A common portion size was identified and subjects were asked how often each item was consumed. Nutrient intake was computed by multiplying the intake frequency and nutrient content per portion for each item, and then by summing the product over all foods. Each nutrient intake was adjusted for energy intake. Alcohol intake was calculated by summing the consumption of wine, beer, and liquor. Having excluded subjects aware of having gallstones (GS) or previously submitted to cholecystectomy (to avoid prothopatic bias), 787 males and 1,014 females with GS and 14,272 males and 10,836 females without GS were available for analysis. Relative risks (RR) of GS were computed by quintiles of nutrient intake. The overnight fasting period was calculated as the difference between the specified time of dinner and the time of the next meal (breakfast or lunch). A significant negative association was found between RR of GS and total energy intake for males (chi2 for trend = 8.37; P = .004), fiber intake for females (chi2 = 5.45; P = .02), and daily alcohol consumption for males (chi2 = 10.86; P = .001). A positive association was observed between RR of GS and carbohydrate (chi2 = 5.95; P = .01 for males; chi2 = 9.39; P = .002 for females) and protein intake only for males (chi2 = 10.92; P = .01). Prevalence of GS was higher among subjects who had an overnight fasting period of over 12 hours than subjects with that of less than 12 hours. (RR: 1.35; 95% CI: 1.01-1.80 for males; RR: 1.28; 95% CI: 1.03-1.60 for females). These data do not confirm that high energy intake is associated with an increased risk of GS. Factors protecting against GS comprise: low carbohydrate (males and females) and protein (males) intakes, high fiber (females) and moderate alcohol intake (males) consumption, and a shorter overnight fasting period for both sexes

Radiomics of Patients with Locally Advanced Rectal Cancer: Effect of Preprocessing on Features Estimation from Computed Tomography Imaging

The purpose of this study was to investigate the effect of image preprocessing on radiomic features estimation from computed tomography (CT) imaging of locally advanced rectal cancer (LARC). CT images of 20 patients with LARC were used to estimate 105 radiomic features of 7 classes (shape, first-order, GLCM, GLDM, GLRLM, GLSZM, and NGTDM). Radiomic features were estimated for 6 different isotropic resampling voxel sizes, using 10 interpolation algorithms (at fixed bin width) and 6 different bin widths (at fixed interpolation algorithm). The intraclass correlation coefficient (ICC) and the coefficient of variation (CV) were calculated to assess the variability in radiomic features estimation due to preprocessing. A repeated measures correlation analysis was performed to assess any linear correlation between radiomic feature estimate and resampling voxel size or bin width. Reproducibility of radiomic feature estimate, when assessed through ICC analysis, was nominally excellent (ICC&gt;0.9) for shape features, good (0.7

Intelligence profiles of children and adolescents with high functioning autism spectrum disorder

In this paper we identify an endophenotype for individuals with Autism spectrum disorder – level 1 (ASD-1) and normal cognitive functioning using the Wechsler Intelligence Scale for Children – Fourth Edition with a clinical sample of 80 diagnosed ASD-1 children without intellectual disability (with FSIQ&gt;70), and a comparison matched-paired control group (n = 80) combined for age, gender of children and parents’ level education. From results emerged that the clinical ASD-1 with High functioning group (ASD-1 HF) performed worse than the matched-paired control group on Processing Speed Index and Working Memory Index, reflecting the sensitivity of these measures to generalized cognitive impairment. This result is also confirmed by the absence of a difference between the ASD-1 HF and control groups in the General Ability Index and the large difference to the Cognitive Proficiency Index in favour of the control group. Again, 36% of ASD children had a rare and large difference between the 4 indices and then the FSIQ could be deemed uninterpretable as unitary and cohesive ability. We argue that the ASD-1’s cognitive profile cannot be interpreted as a unitary entity represented from simply FSIQ, but we can obtain a better assessment of cognitive level in ASD subjects using separately the General Ability Index and the Cognitive Proficiency Index