CT radiomic features reproducibility of virtual non-contrast series derived from photon-counting CCTA datasets using a novel calcium-preserving reconstruction algorithm compared with standard non-contrast series: focusing on epicardial adipose tissue.

PURPOSE: We aimed to evaluate the reproducibility of computed tomography (CT) radiomic features (RFs) about Epicardial Adipose Tissue (EAT). The features derived from coronary photon-counting computed tomography (PCCT) angiography datasets using the PureCalcium (VNCPC) and conventional virtual non-contrast (VNCConv) algorithm were compared with true non-contrast (TNC) series. METHODS: RFs of EAT from 52 patients who underwent PCCT were quantified using VNCPC, VNCConv, and TNC series. The agreement of EAT volume (EATV) and EAT density (EATD) was evaluated using Pearson's correlation coefficient and Bland-Altman analysis. A total of 1530 RFs were included. They are divided into 17 feature categories, each containing 90 RFs. The intraclass correlation coefficients (ICCs) and concordance correlation coefficients (CCCs) were calculated to assess the reproducibility of RFs. The cutoff value considered indicative of reproducible features was > 0.75. RESULTS: the VNCPC and VNCConv tended to underestimate EATVs and overestimate EATDs. Both EATV and EATD of VNCPC series showed higher correlation and agreement with TNC than VNCConv series. All types of RFs from VNCPC series showed greater reproducibility than VNCConv series. Across all image filters, the Square filter exhibited the highest level of reproducibility (ICC = 67/90, 74.4%; CCC = 67/90, 74.4%). GLDM_GrayLevelNonUniformity feature had the highest reproducibility in the original image (ICC = 0.957, CCC = 0.958), exhibiting a high degree of reproducibility across all image filters. CONCLUSION: The accuracy evaluation of EATV and EATD and the reproducibility of RFs from VNCPC series make it an excellent substitute for TNC series exceeding VNCConv series.

Improvement of coronary stent visualization using ultra-high-resolution photon-counting detector CT.

OBJECTIVES: This study aimed to compare the image quality and diagnostic performance of standard-resolution (SR) and ultra-high-resolution (UHR) coronary CT angiography (CCTA) based on photon-counting detector CT (PCD-CT) of coronary stents and explore the best reconstruction kernel for stent imaging. METHODS: From July 2023 to September 2023, patients were enrolled to undergo CCTA using a dual-source PCD-CT system after coronary angioplasty with stent placement. SR images with a slice thickness/increment of 0.6/0.4 mm were reconstructed using a vascular kernel (Bv48), while UHR images with a slice thickness/increment of 0.2/0.2 mm were reconstructed using vascular kernels of six sharpness levels (Bv48, Bv56, Bv60, Bv64, Bv72, and Bv76). The in-stent lumen diameters were evaluated. Subjective image quality was also evaluated by a 5-point Likert scale. Invasive coronary angiography was conducted in 12 patients (25 stents). RESULTS: Sixty-nine patients (68.0 [61.0, 73.0] years, 46 males) with 131 stents were included. All UHR images had significantly larger in-stent lumen diameter than SR images (p < 0.001). Specifically, UHR-Bv72 and UHR-Bv76 for in-stent lumen diameter (2.17 [1.93, 2.63] mm versus 2.20 [1.93, 2.59] mm) ranked the two best kernels. The subjective analysis demonstrated that UHR-Bv72 images had the most pronounced effect on reducing blooming artifacts, showcasing in-stent lumen and stent demonstration, and diagnostic confidence (p < 0.001). Furthermore, SR and UHR-Bv72 images showed a diagnostic accuracy of 78.3% (95% confidence interval [CI]: 56.3%-92.5%) and 88.0% (95%CI: 68.8%-97.5%), respectively. CONCLUSION: UHR CCTA by PCD-CT leads to significantly improved visualization and diagnostic performance of coronary stents, and Bv72 is the optimal reconstruction kernel showing the stent struts and in-stent lumen. CLINICAL RELEVANCE STATEMENT: The significantly improved visualization of coronary stents using ultra-high resolution CCTA could increase the diagnostic accuracy for in-stent restenosis and avoid unnecessary invasive quantitative coronary angiography, thus changing the clinical management for patients after percutaneous coronary intervention. KEY POINTS: Coronary stent imaging is challenging with energy-integrating detector CT due to "blooming artifacts." UHR images using a PCD-CT enhanced coronary stent visualization. UHR coronary stent imaging demonstrated improved diagnostic accuracy in clinical settings.

Impacts of Adaptive Statistical Iterative Reconstruction-V and Deep Learning Image Reconstruction Algorithms on Robustness of CT Radiomics Features: Opportunity for Minimizing Radiomics Variability Among Scans of Different Dose Levels.

This study aims to investigate the influence of adaptive statistical iterative reconstruction-V (ASIR-V) and deep learning image reconstruction (DLIR) on CT radiomics feature robustness. A standardized phantom was scanned under single-energy CT (SECT) and dual-energy CT (DECT) modes at standard and low (20 and 10 mGy) dose levels. Images of SECT 120 kVp and corresponding DECT 120 kVp-like virtual monochromatic images were generated with filtered back-projection (FBP), ASIR-V at 40% (AV-40) and 100% (AV-100) blending levels, and DLIR algorithm at low (DLIR-L), medium (DLIR-M), and high (DLIR-H) strength levels. Ninety-four features were extracted via Pyradiomics. Reproducibility of features was calculated between standard and low dose levels, between reconstruction algorithms in reference to FBP images, and within scan mode, using intraclass correlation coefficient (ICC) and concordance correlation coefficient (CCC). The average percentage of features with ICC > 0.90 and CCC > 0.90 between the two dose levels was 21.28% and 20.75% in AV-40 images, and 39.90% and 35.11% in AV-100 images, respectively, and increased from 15.43 to 45.22% and from 15.43 to 44.15% with an increasing strength level of DLIR. The average percentage of features with ICC > 0.90 and CCC > 0.90 in reference to FBP images was 26.07% and 25.80% in AV-40 images, and 18.88% and 18.62% in AV-100 images, respectively, and decreased from 27.93 to 17.82% and from 27.66 to 17.29% with an increasing strength level of DLIR. DLIR and ASIR-V algorithms showed low reproducibility in reference to FBP images, while the high-strength DLIR algorithm provides an opportunity for minimizing radiomics variability due to dose reduction.

[Effects of water levels in heterogeneous habitats on sexual reproductive allocation of Deyeuxia angustifolia.] / å¼‚è´¨ç”Ÿå¢ƒæ°´ä½å·®å¼‚å¯¹å°å¶ç« æœ‰æ€§ç¹æ®–åˆ†é çš„å½±å“.

Taking Deyeuxia angustifolia as the research object, a representative plant of wetland in Sanjiang Plain, we analyzed the variations of individual size and biomass among the habitats of swamp wetlands, swampy meadows, typical meadows and miscellaneous grass meadows, and the relationship between reproductive components and plant biomass. We explored the effects of water level on individual biomass and reproductive allocation of D. angustifolia in different types of wetlands. The results showed that plant biomass, height and the characteristics of sexual reproduction significantly decreased with the increases of water level. The reproductive thresholds of D. angustifolia in miscellaneous grass meadow, typical meadow, swampy meadow, and swamp wetland were 0.245, 0.149, 0.148 and 0.157 g, respectively. There was a significantly negative correlation between plant size and reproductive allocation in three habitats except swampy meadow. Compared with individual size, soil water content had a stronger effect on reproductive allocation of D. angustifolia. The different investment between individual size and reproductive allocation in different habitats was the basic condition that contributes to the good ecological adaptability of D. angustifolia.

Cohort protocol: Guangzhou High-Risk Infant Cohort study.

INTRODUCTION: Despite the increase in the survival rate of high-risk infants (HRIs) worldwide, the prevalence of motor and neurodevelopmental sequelae in such newborns has not shown concomitant improvement. Meanwhile, there are few cohorts that explore factors related to the development of HRIs in China. Therefore, the Guangzhou High-Risk Infant Cohort (GHRIC) has been designed to examine the complex relationships among a myriad of factors influencing growth and development in such children. METHODS AND ANALYSIS: The GHRIC study is a prospective cohort study that by the year 2023 will enrol an estimated total of 3000 HRIs from Guangzhou Women and Children's Medical Center (GWCMC) in Guangzhou, China. This study is designed to assess the growth and cognitive characteristics of HRIs and the risk factors affecting their development and prognoses. Data on risk factors, neurodevelopmental and cognitive-function evaluations, laboratory results, and specimens will be collected and analysed. Information on perinatal and clinical interventions for these infants will also be recorded during regular follow-up visits until age 6. ETHICS AND DISSEMINATION: The protocol for this study has been approved by the Research Ethics Committee of GWCMC, which accepted responsibility for supervising all of the aspects of the study (No. 2017102712). Study outcomes will be disseminated through conference presentations, peer-reviewed publications, the Internet and social media. TRIAL REGISTRATION NUMBER: ChiCTR-EOC-17013236.

Excessive Methionine Supplementation Exacerbates the Development of Abdominal Aortic Aneurysm in Rats.

OBJECTIVE: The relationship between methionine (Met) and abdominal aortic aneurysm (AAA) has been previously demonstrated, but the mechanisms controlling this association remain unclear. This study investigated the potential contribution of hypermethioninemia (HMet) to the development of AAA. METHODS: A model of AAA was induced by intraluminal porcine pancreatic elastase (PPE) infusion in 60 male Sprague-Dawley rats divided into 4 groups (n = 15 per group). Met was supplied by intragastric administration (1 g/kg body weight/day) from 1 week before surgery until 4 weeks after surgery. The aortic diameter was measured by ultrasound. Aortas were collected 4 weeks after surgery and subjected to biochemical analysis, histological assays, and transmission electron microscopy. RESULTS: After 5 weeks of Met supplementation, HMet increased the dilation ratio of the HMet + PPE group, and hyperhomocysteinemia was also induced in HMet and HMet + PPE rats. Increased matrix metalloproteinase-2 (MMP-2), osteopontin, and interleukin-6 expression was detected in HMet + PPE rats. Furthermore, increased autophagy was detected in the HMet + PPE group. CONCLUSION: This study demonstrates that HMet may exacerbate the formation of AAA due to the increased dilation ratio partially via enhancing MMP-2 and inflammatory responses.

Translational and Rotational Dynamical Heterogeneities in Granular Systems.

We use x-ray tomography to investigate the translational and rotational dynamical heterogeneities of a three dimensional hard ellipsoid granular packing driven by oscillatory shear. We find that particles which translate quickly form clusters with a size distribution given by a power law with an exponent that is independent of the strain amplitude. Identical behavior is found for particles that are translating slowly, rotating quickly, or rotating slowly. The geometrical properties of these four different types of clusters are the same as those of random clusters. Different cluster types are considerably correlated or anticorrelated, indicating a significant coupling between translational and rotational degrees of freedom. Surprisingly, these clusters are formed already at time scales that are much shorter than the α-relaxation time, in stark contrast to the behavior found in glass-forming systems.

Early growth response factor-1 DNA enzyme 1 inhibits the formation of abdominal aortic aneurysm in rats.

The aim of the present study was to characterize the effects of early growth response factor-1 DNA enzyme (EDRz) in a rat abdominal aortic aneurysm (AAA) model to determine the mechanism by which EDRz inhibits AAA and affects the formation of AAA by regulating the activity of matrix metalloproteinase (MMP)-2 and MMP-9. EDRz was transfected into the abdominal aorta of rats using the jetPRIME transfection reagent following infusion with elastase. Fluorescent microscopy, hematoxylin and eosin staining, ultrastructural analysis, reverse transcription-quantitative polymerase chain reaction, western blotting and immunohistochemical analysis were performed to characterize the response to EDRz. The EDRz group showed minimal aneurysm formation when compared with the control group, with significantly lower aortic diameter expansion (2.5±0.1 vs. 3.5±0.1 mm; P<0.05). Early growth response factor 1 (Egr-1) mRNA and protein levels were significantly decreased in the EDRz group, as expected. The decrease in Egr-1 was accompanied by decreases in the mRNA and protein levels of MMP-2 and MMP-9 (P<0.05). Transfection of the Egr-1 specific synthetic DNA enzyme EDRz significantly reduced AAA following elastase infusion in rats, at least in part due to the decreased expression of downstream MMP-2 and MMP-9.

Quantitative analysis of hepatic iron in patients suspected of coexisting iron overload and steatosis using multi-echo single-voxel magnetic resonance spectroscopy: Comparison with fat-saturated multi-echo gradient echo sequence.

BACKGROUND: The coexistence of hepatic iron and fat is common in patients with hyperferritinemia, which plays an interactive and aggressive role in the progression of diseases (fibrosis, cirrhosis, and hepatocellular carcinomas). PURPOSE: To evaluate a modified high-speed T2 -corrected multi-echo, single voxel spectroscopy sequence (HISTOV) for liver iron concentration (LIC) quantification in patients with hyperferritinemia, with simultaneous fat fraction (FF) estimation. STUDY TYPE: Retrospective cohort study. POPULATION: Thirty-eight patients with hyperferritinemia were enrolled. FIELD STRENGTH/SEQUENCE: HISTOV, a fat-saturated multi-echo gradient echo (GRE) sequence, and a spin echo sequence (FerriScan) were performed at 1.5T. ASSESSMENT: R2 of the water signal and FF were calculated with HISTOV, and R2* values were derived from the GRE sequence, with R2 and LIC from FerriScan serving as the references. STATISTICAL TESTS: Linear regression, correlation analyses, receiver operating characteristic analyses, and Bland-Altman analyses were conducted. RESULTS: Abnormal hepatic iron load was detected in 32/38 patients, of whom 10/32 had coexisting steatosis. Strong correlation was found between R2* and FerriScan-LIC (R2 = 0.861), and between HISTOV-R2_ water and FerriScan-R2 (R2 = 0.889). Furthermore, HISTOV-R2_ water was not correlated with HISTOV-FF. The area under the curve (AUC) for HISTOV-R2_ water was 0.974, 0.971, and 1, corresponding to clinical FerriScan-LIC thresholds of 1.8, 3.2, and 7.0 mg/g dw, respectively. No significant difference in the AUC was found between HISTOV-R2_ water and R2* at any of the LIC thresholds, with P-values of 0.42, 0.37, and 1, respectively. HISTOV-LIC showed excellent agreement with FerriScan-LIC, with a mean bias of 0.00 ± 1.18 mg/g dw, whereas the mean bias between GRE-LIC and FerriScan-LIC was 0.53 ± 1.49 mg/g dw. DATA CONCLUSION: HISTOV is useful for the quantification and grading of liver iron overload in patients with hyperferritinemia, particularly in cases with coexisting steatosis. HISTOV-LIC showed no systematic bias compared with FerriScan-LIC, making it a promising alternative for iron quantification. LEVEL OF EVIDENCE: 3 Technical Efficacy Stage 2 J. Magn. Reson. Imaging 2018.

Association of leptin with disease severity and inflammation indicators in Chinese obese children with allergic rhinitis.

BACKGROUND: The prevalence of both obesity and allergic diseases in children has increased over the last several decades. However, the direct relationship between diverse allergic diseases and obesity has varied in different studies. Therefore, we aimed to examine the effect of obesity on the incidence and severity of allergic rhinitis (AR) and the possible key inflammation mediators during AR. METHODS: A total of 3126 healthy students (without chronic diseases) were recruited from 14 randomly selected secondary schools in Guangzhou, China. Body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHR), and body fat percentage (PBF) were measured and compared. The effect of obesity indicators and leptin level (exposures) on the incidence (primary outcome) and severity of AR (secondary outcomes) was analyzed. Inflammatory markers were detected and compared among groups. RESULTS: The symptom score (9.5 ± 3.1 vs 8.2 ± 3.5, P < .05) and medication score (3.6 ± 1.6 vs 2.9 ± 1.8, P < .05) were significantly higher in obese children with AR than in non-obese children with AR. After adjusting for potential confounders, multiple linear regression analysis showed that the serum leptin concentration was significantly correlated with the levels of T-helper (TH) 2 cytokines (coefficient, 0.48 [95% CI, 0.05-0.91]), TH17 cytokines (coefficient, 0.39 [95% CI, 0.11-0.89]), and regulatory T-cell cytokines (IL-10, coefficient, -0.43 [95% CI, -0.02-0.65]; TGF-ß, coefficient, -0.65 [95% CI, -0.06-1.35]) in patients with AR. CONCLUSIONS: Our study shows that obesity exacerbates inflammation and contributes to disease severity in AR. Our study provides evidence that leptin was involved in enhanced TH inflammation as well as the accumulation and activation of inflammatory cells in obese children with AR.

Granular materials flow like complex fluids.

Granular materials such as sand, powders and foams are ubiquitous in daily life and in industrial and geotechnical applications. These disordered systems form stable structures when unperturbed, but in the presence of external influences such as tapping or shear they 'relax', becoming fluid in nature. It is often assumed that the relaxation dynamics of granular systems is similar to that of thermal glass-forming systems. However, so far it has not been possible to determine experimentally the dynamic properties of three-dimensional granular systems at the particle level. This lack of experimental data, combined with the fact that the motion of granular particles involves friction (whereas the motion of particles in thermal glass-forming systems does not), means that an accurate description of the relaxation dynamics of granular materials is lacking. Here we use X-ray tomography to determine the microscale relaxation dynamics of hard granular ellipsoids subject to an oscillatory shear. We find that the distribution of the displacements of the ellipsoids is well described by a Gumbel law (which is similar to a Gaussian distribution for small displacements but has a heavier tail for larger displacements), with a shape parameter that is independent of the amplitude of the shear strain and of the time. Despite this universality, the mean squared displacement of an individual ellipsoid follows a power law as a function of time, with an exponent that does depend on the strain amplitude and time. We argue that these results are related to microscale relaxation mechanisms that involve friction and memory effects (whereby the motion of an ellipsoid at a given point in time depends on its previous motion). Our observations demonstrate that, at the particle level, the dynamic behaviour of granular systems is qualitatively different from that of thermal glass-forming systems, and is instead more similar to that of complex fluids. We conclude that granular materials can relax even when the driving strain is weak.

Effect of bronchopulmonary dysplasia on early intellectual development in preterm infants.

BACKGROUND: The aim of this study was to investigate the effect of bronchopulmonary dysplasia (BPD) on the early intellectual development of preterm infants. METHODS: From 2011 to 2015, 83 preterm infants diagnosed with BPD were recruited to the BPD group, and 89 preterm infants without BPD and 98 healthy term infants were randomly recruited to the non-BPD and term group, respectively. Neural and intellectual development according to the Gesell Development Scale were evaluated and compared between groups at 0-3 months, 3-6 months, 6-9 months, and 9-12 months of adjusted age for preterm infants and real age for term infants. Multivariate logistic regression was used to determine the associations between BPD and adverse neurological outcomes at 9-12 months of adjusted age. RESULTS: Compared with term infants, preterm infants had significantly lower developmental quotients for adaptability, gross motor, fine motor, language and social skills. At follow up, deficits in one or more neurofunctions related to adaptability, gross motor, fine motor, language and social skills were significantly more frequent in preterm children with BPD than in those with no history of BPD. BPD was independently associated with adverse neurological outcome at 9-12 months of adjusted age in preterm infants. CONCLUSIONS: Early intelligence disturbances occurred significantly more frequently in BPD infants than in non-BPD infants. Monitoring of the development of the nervous system in BPD infants should be strengthened.

High-Pitch Dual-Source Computed Tomography Renal Angiography Comparison With Conventional Low-Pitch Computed Tomography Angiography: Image Quality, Contrast Medium Volume, and Radiation Dose.

OBJECTIVE: The objective of this study was to compare the image quality (IQ), contrast medium (CM) volume, and radiation dose of the high-pitch renal computed tomography angiography (CTA) with low-pitch protocol. METHODS: Fifty patients underwent renal CTA on a dual-source 128-slice scanner via a high-pitch mode (pitch = 2.05) with 0.5-mL/kg CM injection, whereas 50 patients were also scanned on the same scanner with low-pitch (pitch = 0.6) and 1.0 mL/kg CM injection. Subjective IQ was evaluated. Objective IQ was determined by the signal-to-noise ratio and contrast-to-noise ratio. Effective radiation dose was also evaluated. RESULTS: The contrast-to-noise ratio and signal-to-noise ratio values as well as the IQ scores between the 2 groups had no significant differences (P > 0.05). The effective radiation dose of the high-pitch group was significantly lower (P < 0.05). CONCLUSIONS: High-pitch scan can provide similar subjective and objective IQ compared with low-pitch protocol for renal CTA, whereas CM volume and radiation exposure were significantly reduced.

[Building and application of hospital's electronic film system].

This paper describes the design process and implementation process of electronic film system. The establishment of electronic film system allowed us to aggressively reduce film use and costs and to demonstrate a positive return.

[The value of electronic film for improving the quality of hospital services].

In this paper, by describing and comparing different implementations of electronic film combined with the actual application of the electronic film in the imaging department and the clinical departments. We elaborate electronic film for optimizing the imaging department workflow to improve service quality and patient satisfaction and other aspects of value.