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1.
J Affect Disord ; 273: 32-40, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32421620

RESUMO

BACKGROUND: FK506 binding protein 5 (FKBP5) rs1360780 polymorphism has been identified as a molecular genetic marker associated with the dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis. The impact of FKBP5 rs1360780 on the large-scale brain network connectivity in healthy adults is still unknown. METHODS: 479 healthy volunteers (age: 20-80years) completed MRI scans, neuropsychological assessments and blood analysis.All subjects were divided into CC, CT and TT genotypes. Within and between network connectivities (10 sub-networks) were calculated using resting state functional MRI (rs-fMRI) data. The genetic effects and gene-gender/age interaction on large-scale network connectivity were explored. RESULTS: Compared with CC and CT groups, TT group showed increased intra-connectivity in default mode network (DMN) and increased inter-connectivity mainly distributed among the network of DMN, salience network (SAN), dorsal attention network (DAN), ventral attention network (VAN), subcortical network (SUB), and visual network (VIS). Gene-by-gender and gene-by-age interaction were found in inter-connectivity of DAN to VIS and DMN to FPN, respectively. The altered connectivities correlated with anxiety status test score. LIMITATIONS: Plasma adrenocorticotropic hormone (ACTH) or cortisol were not measured,or else, we could estimate the hypothalamic-pituitary-adrenal (HPA) axis activity which may strengthen our results. CONCLUSIONS: FKBP5 rs1360780 modulates the large-scale brain network connectivity in healthy adults. TT carriers showed the increased intra- and inter-connectivities mainly distributed among the network of DMN, SAN, DAN, VAN, SUB and VIS.

2.
Eur Radiol ; 2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32462444

RESUMO

OBJECTIVES: This study investigated the impact of machine learning (ML)-based fractional flow reserve derived from computed tomography (FFRCT) compared to invasive coronary angiography (ICA) for therapeutic decision-making and patient outcome in patients with suspected coronary artery disease (CAD). METHODS: One thousand one hundred twenty-one consecutive patients with stable chest pain who underwent coronary computed tomography angiography (CCTA) followed ICA within 90 days between January 2007 and December 2016 were included in this retrospective study. Medical records were reviewed for the endpoint of major adverse cardiac events (MACEs). FFRCT values were calculated using an artificial intelligence (AI) ML platform. Disagreements between hemodynamic significant stenosis via FFRCT and severe stenosis on qualitative CCTA and ICA were also evaluated. RESULTS: After FFRCT results were revealed, a change in the proposed treatment regimen chosen based on ICA results was seen in 167 patients (14.9%). Over a median follow-up time of 26 months (4-48 months), FFRCT ≤ 0.80 was associated with MACE (HR, 6.84 (95% CI, 3.57 to 13.11); p < 0.001), with superior prognostic value compared to severe stenosis on ICA (HR, 1.84 (95% CI, 1.24 to 2.73), p = 0.002) and CCTA (HR, 1.47 (95% CI, 1.01 to 2.14, p = 0.045). Reserving ICA and revascularization for vessels with positive FFRCT could have reduced the rate of ICA by 54.5% and lead to 4.4% fewer percutaneous interventions. CONCLUSIONS: This study indicated ML-based FFRCT had superior prognostic value when compared to severe anatomic stenosis on CCTA and adding FFRCT may direct therapeutic decision-making with the potential to improve efficiency of ICA. KEY POINTS: • ML-based FFRCTshows superior outcome prediction value when compared to severe anatomic stenosis on CCTA. • FFRCTnoninvasively informs therapeutic decision-making with potential to change diagnostic workflows and enhance efficiencies in patients with suspected CAD. • Reserving ICA and revascularization for vessels with positive FFRCTmay reduce the normalcy rate of ICA and improve its efficiency.

3.
Eur Radiol ; 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32350658

RESUMO

OBJECTIVES: To build models based on conventional logistic regression (LR) and machine learning (ML) algorithms combining clinical, morphological, and hemodynamic information to predict individual rupture status of unruptured intracranial aneurysms (UIAs), afterwards tested in internal and external validation datasets. METHODS: Patients with intracranial aneurysms diagnosed by computed tomography angiography and confirmed by invasive cerebral angiograph or clipping surgery were included. The prediction models were developed based on clinical, aneurysm morphological, and hemodynamic parameters by conventional LR and ML methods. RESULTS: The training, internal validation, and external validation cohorts were composed of 807 patients, 200 patients, and 108 patients, respectively. The area under curves (AUCs) of conventional LR models 1 (clinical), 2 (clinical and aneurysm morphological), and 3 (clinical, aneurysm morphological and hemodynamic characteristics) were 0.608, 0.765, and 0.886, respectively (all p < 0.05). The AUCs of ML models using random forest (RF), multilayer perceptron (MLP), and support vector machine (SVM) were 0.871, 0.851, and 0.863, respectively. There were no difference among AUCs of conventional LR, RF, and SVM (all p > 0.05/6), while the AUC of MLP was lower than that of conventional LR (p = 0.0055). CONCLUSION: Hemodynamic parameters play an important role in the prediction performance of the models. ML methods cannot outperform conventional LR in prediction models for rupture status of UIAs integrating clinical, aneurysm morphological, and hemodynamic parameters. KEY POINTS: • The addition of hemodynamic parameters can improve prediction performance for rupture status of unruptured intracranial aneurysms. • Machine learning algorithms cannot outperform conventional logistic regression in prediction models for rupture status integrating clinical, aneurysm morphological, and hemodynamic parameters. • Models integrating clinical, aneurysm morphological, and hemodynamic parameters may help choose the optimal management.

4.
J Thorac Imaging ; 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32366759

RESUMO

The ongoing outbreak of Coronavirus Disease 2019 (COVID-19) has spread rapidly throughout China and other countries, and has been characterized as a pandemic. With the strict prevention and control measures implemented by the Chinese government, the spread of the epidemic in China has come under preliminary control by the end of February, 2020, whereas the situation of some countries outside China is not optimistic and raises great public concern. In fighting COVID-19, radiologic examinations played a critical role in the early diagnosis of COVID-19, and could also help assess disease course and severity. There is an urgent need to share useful experience and effective measures internationally. This article outlines the collaborative actions and efforts by the Chinese radiology field and the situation of front-line health care workers in radiology departments to present the world with experiences and examples of Chinese radiology during the COVID-19 outbreak.

5.
Brain Imaging Behav ; 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32304020

RESUMO

Patients with end-stage renal disease (ESRD) are notably accompanied by cognitive disorder and anxiety or depressive symptom. We aimed to explore the linkages of the amygdala-based MR parameters, cognitive and mood performance, systematic inflammation and gut microbiota in ESRD. This prospective study enrolled 28 ESRD patients (13 males and 15 females, mean age of 43.9 ± 13.8 years) and 19 age- and sex-matched healthy control (HC) (12 males and 7 females, mean age of 44.1 ± 10.0 years). All subjects underwent cognitive assessment, inflammatory factor and stool microbiota analysis, and brain MRI analysis [amygdala-based functional connectivity and voxel-based morphometry (VBM)]. ERSD was separated by different microbiota strains. All factors were compared between ESRD and HC, as well as between ESRD subgroups. Pearson correlation analysis and causal mediation analysis were conducted to further investigate the relationship among the factors derived from the gut microbiota, brain and systemic inflammation. ESRD displayed gut dysbiosis and increased systemic inflammation when compared to HC (all P < 0.05). Meanwhile, ESRD showed smaller VBM in amygdala, decreased functional connectivity in left amygdala - right inferior parietal lobe [P < 0.05, Gaussian Random Field (GRF) corrected] and worse cognitive or mood performance. Moreover, ESRD-B (Prevutella mainly), when compared to ESRD-A (Bacteroides mainly), displayed increased interleukin-6, self-rating anxiety scale and functional connectivity in left amygdala - bilateral anterior cingulate cortex / medial superior frontal cortex (P < 0.05, GRF corrected). Furthermore, the correlation network of ESRD showed that both gut dysbiosis and amygdala-based alteration were correlated with cognitive performance and systemic inflammation. Causal mediation analysis validated that the disrupted distribution of Roseburia indirectly regulated the amygdala-based functional connectivity through tumor necrosis factor-alpha. The gut dysbiosis induced by ESRD was closely related to pro-inflammatory cytokines, amygdala-based phenotype, and mood performance. The lower abundance in Roseburia indirectly modulated amygdala-based functional connectivity pattern by tumor necrosis factor-alpha, which might provide a new way in diagnosis and treatment in patients of ESRD with depressive/anxious mood.

6.
Phys Med Biol ; 65(9): 095012, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32182595

RESUMO

Epicardial adipose tissue (EAT) is a visceral fat deposit, that's known for its association with factors, such as obesity, diabetes mellitus, age, and hypertension. Segmentation of the EAT in a fast and reproducible way is important for the interpretation of its role as an independent risk marker intricate. However, EAT has a variable distribution, and various diseases may affect the volume of the EAT, which can increase the complexity of the already time-consuming manual segmentation work. We propose a 3D deep attention U-Net method to automatically segment the EAT from coronary computed tomography angiography (CCTA). Five-fold cross-validation and hold-out experiments were used to evaluate the proposed method through a retrospective investigation of 200 patients. The automatically segmented EAT volume was compared with physician-approved clinical contours. Quantitative metrics used were the Dice similarity coefficient (DSC), sensitivity, specificity, Jaccard index (JAC), Hausdorff distance (HD), mean surface distance (MSD), residual mean square distance (RMSD), and the center of mass distance (CMD). For cross-validation, the median DSC, sensitivity, and specificity were 92.7%, 91.1%, and 95.1%, respectively, with JAC, HD, CMD, MSD, and RMSD are 82.9% ± 8.8%, 3.77 ± 1.86 mm, 1.98 ± 1.50 mm, 0.37 ± 0.24 mm, and 0.65 ± 0.37 mm, respectively. For the hold-out test, the accuracy of the proposed method remained high. We developed a novel deep learning-based approach for the automated segmentation of the EAT on CCTA images. We demonstrated the high accuracy of the proposed learning-based segmentation method through comparison with ground truth contour of 200 clinical patient cases using 8 quantitative metrics, Pearson correlation, and Bland-Altman analysis. Our automatic EAT segmentation results show the potential of the proposed method to be used in computer-aided diagnosis of coronary artery diseases (CADs) in clinical settings.

7.
Eur Radiol ; 30(5): 2525-2534, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32006167

RESUMO

OBJECTIVE: To investigate the effect of image quality of coronary CT angiography (CCTA) on the diagnostic performance of a machine learning-based CT-derived fractional flow reserve (FFRCT). METHODS: This nationwide retrospective study enrolled participants from 10 individual centers across China. FFRCT analysis was performed in 570 vessels in 437 patients. Invasive FFR and FFRCT values ≤ 0.80 were considered ischemia-specific. Four-score subjective assessment based on image quality and objective measurement of vessel enhancement was performed on a per-vessel basis. The effects of body mass index (BMI), sex, heart rate, and coronary calcium score on the diagnostic performance of FFRCT were studied. RESULTS: Among 570 vessels, 216 were considered ischemia-specific by invasive FFR and 198 by FFRCT. Sensitivity and specificity of FFRCT for detecting lesion-specific ischemia were 0.82 and 0.93, respectively. Area under the curve (AUC) of high-quality images (0.93, n = 159) was found to be superior to low-quality images (0.80, n = 92, p = 0.02). Objective image quality and heart rate were also associated with diagnostic performance of FFRCT, whereas there was no statistical difference in diagnostic performance among different BMI, sex, and calcium score groups (all p > 0.05, Bonferroni correction). CONCLUSIONS: This retrospective multicenter study supported the FFRCT as a noninvasive test in evaluating lesion-specific ischemia. Subjective image quality, vessel enhancement, and heart rate affect the diagnostic performance of FFRCT. KEY POINTS: • FFRCTcan be used to evaluate lesion-specific ischemia. • Poor image quality negatively affects the diagnostic performance of FFRCT. • CCTA with ≥ score 3, intracoronary enhancement degree of 300-400 HU, and heart rate below 70 bpm at scanning could be of great benefit to more accurate FFRCTanalysis.

8.
Radiology ; : 200490, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32083985

RESUMO

In December 2019, an outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection occurred in Wuhan, Hubei Province, China and spread across China and beyond. On February 12, 2020, WHO officially named the disease caused by the novel coronavirus as Coronavirus Disease 2019 (COVID-19). Since most COVID-19 infected patients were diagnosed with pneumonia and characteristic CT imaging patterns, radiological examinations have become vital in early diagnosis and assessment of disease course. To date, CT findings have been recommended as major evidence for clinical diagnosis of COVID-19 in Hubei, China. This review focuses on the etiology, epidemiology, and clinical symptoms of COVID-19, while highlighting the role of chest CT in prevention and disease control. A full translation of this article in Chinese is available.

9.
Korean J Radiol ; 21(2): 192-202, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31997594

RESUMO

OBJECTIVE: To examine the fractional flow reserve derived from computed tomographic angiography (CT-FFR) in patients with anomalous origin of the right coronary artery from the left coronary sinus (R-ACAOS) with an interarterial course, assess the relationship of CT-FFR with the anatomical features of interarterial R-ACAOS on coronary computed tomographic angiography (CCTA), and determine its clinical relevance. MATERIALS AND METHODS: Ninety-four patients with interarterial R-ACAOS undergoing CCTA were retrospectively included. Anatomic features (proximal vessel morphology [oval or slit-like], take-off angle, take-off level [below or above the pulmonary valve], take-off type, intramural course, % proximal narrowing area, length of narrowing, minimum luminal area [MLA] at systole and diastole, and vessel compression index) on CCTA associated with CT-FFR ≤ 0.80 were analyzed. Receiver operating characteristic analysis was performed to describe the diagnostic performance of CT-FFR ≤ 0.80 in detecting interarterial R-ACAOS. RESULTS: Significant differences were found in proximal vessel morphology, take-off level, intramural course, % proximal narrowing area, and MLA at diastole (all p < 0.05) between the normal and abnormal CT-FFR groups. Take-off level, intramural course, and slit-like ostium (all p < 0.05) predicted hemodynamic abnormality (CT-FFR ≤ 0.80) with accuracies of 0.69, 0.71, and 0.81, respectively. Patients with CT-FFR ≤ 0.80 had a higher prevalence of typical angina (29.4% vs. 7.8%, p = 0.025) and atypical angina (29.4% vs. 6.5%, p = 0.016). CONCLUSION: Take-off level, intramural course, and slit-like ostium were the main predictors of abnormal CT-FFR values. Importantly, patients with abnormal CT-FFR values showed a higher prevalence of typical angina and atypical angina, indicating that CT-FFR is a potential tool to gauge the clinical relevance in patients with interarterial R-ACAOS.

10.
Mol Psychiatry ; 25(3): 517-529, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31827248

RESUMO

The Chinese Imaging Genetics (CHIMGEN) study establishes the largest Chinese neuroimaging genetics cohort and aims to identify genetic and environmental factors and their interactions that are associated with neuroimaging and behavioral phenotypes. This study prospectively collected genomic, neuroimaging, environmental, and behavioral data from more than 7000 healthy Chinese Han participants aged 18-30 years. As a pioneer of large-sample neuroimaging genetics cohorts of non-Caucasian populations, this cohort can provide new insights into ethnic differences in genetic-neuroimaging associations by being compared with Caucasian cohorts. In addition to micro-environmental measurements, this study also collects hundreds of quantitative macro-environmental measurements from remote sensing and national survey databases based on the locations of each participant from birth to present, which will facilitate discoveries of new environmental factors associated with neuroimaging phenotypes. With lifespan environmental measurements, this study can also provide insights on the macro-environmental exposures that affect the human brain as well as their timing and mechanisms of action.

11.
Can J Cardiol ; 35(11): 1523-1533, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31679622

RESUMO

BACKGROUND: The diagnostic performance of coronary computed tomography angiography-derived fractional flow reserve (CT-FFR) in detecting ischemia in myocardial bridging (MB) has not been investigated to date. METHODS: This retrospective multicentre study included 104 patients with left anterior descending MBs. MB was classified as either superficial or deep, short, or long, whereas all MB vessels were further divided into <50%, 50% to 69%, and ≥70% groups, according to proximal lumen stenosis on invasive coronary angiography. Diagnostic performance and receiver operating characteristics (ROC) of CT-FFR to detect lesion-specific ischemia was assessed on a per-vessel level, using invasive FFR as reference standard. Intraclass correlation coefficient (ICC) and Bland-Altman plots were used for agreement measurement. RESULTS: Forty-eight MB vessels (46.2%) showed ischemia by invasive FFR (≤0.80). Sensitivity, specificity, and accuracy of CT-FFR to detect functional ischemia were 0.96 (0.85 to 0.99), 0.84 (0.71 to 0.92), and 0.89 (0.81 to 0.94), respectively, in all MB vessels. There were no differences in diagnostic performance between superficial and deep MB or between short and long MB (all P > 0.05). The accuracy of CT-FFR was 0.96 (0.85 to 0.99) in ≥70% stenosis, 0.82 (0.67 to 0.91) in 50% to 69% stenosis, and 0.89 (0.51 to 0.99) in <50% stenosis (P = 0.081). Bland-Altman analysis showed a slight mean difference between CT-FFR and invasive FFR of 0.014 (95% limit of agreement, -0.117 to 0.145). The ICC was 0.775 (95% confidence interval, 0.685-0.842, P < 0.001). CONCLUSIONS: CT-FFR demonstrated high diagnostic performance for identifying functional ischemia in vessels with MB and concomitant proximal atherosclerotic disease when compared with invasive FFR. However, the clinical use of CT-FFR in patients with MB needs further study for stronger and more robust results.

13.
Theranostics ; 9(26): 8171-8181, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31754388

RESUMO

The gut-brain axis in end-stage renal disease (ESRD) is attracting more and more attention. However, the mechanism of gut-brain axis based cognitive disorders in ESRD patients remains unclear. The purpose of this study was to investigate the linkages between the gut microbiota, inflammatory cytokines, brain default mode network (DMN) and cognitive function in ESRD patients. Methods: This prospective study enrolled 28 ESRD patients (13 males and 15 females, mean age of 44 ± 14 years) and 19 healthy controls (HCs) (12 males and 7 females, mean age of 44 ± 10 years). All subjects underwent stool microbiota analysis, blood inflammatory cytokines examination, brain MRI scans and cognitive assessments. Resting state functional MRI (rs-fMRI) data were used to construct DMN and graph theory was applied to characterize network topological properties. Two samples t-test was applied for the comparisons between ESRD and HCs. Correlation analysis and mediation analysis were conducted among factors with significant group differences. Results: ESRD patients displayed gut microbiota alterations, increased systemic inflammation and worse cognitive performance compared to HCs (all p < 0.05). Graph analysis revealed disrupted DMN topological organization, aberrant nodal centralities and functional connectivities (FCs) in ESRD patients relative to HCs (all p < 0.05, FDR corrected). Significant correlations were found between gut microbiota, inflammatory cytokines, DMN network measures and cognitive assessments. Mediation analysis found that gut microbiota alteration impaired DMN connectivity by increasing systemic inflammation. Conclusion: The present study first revealed gut microbiota alterations, systemic inflammation, DMN dissociation and cognitive dysfunction in ESRD patients simultaneously and further illuminated their inner relationship.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31422138

RESUMO

OBJECTIVES: The aim of this study was to validate the feasibility of a novel structural and computational fluid dynamics-based fractional flow reserve (FFR) algorithm for coronary computed tomography angiography (CTA), using alternative boundary conditions to detect lesion-specific ischemia. BACKGROUND: A new model of computed tomographic (CT) FFR relying on boundary conditions derived from structural deformation of the coronary lumen and aorta with transluminal attenuation gradient and assumptions regarding microvascular resistance has been developed, but its accuracy has not yet been validated. METHODS: A total of 338 consecutive patients with 422 vessels from 9 Chinese medical centers undergoing CTA and invasive FFR were retrospectively analyzed. CT FFR values were obtained on a novel on-site computational fluid dynamics-based CT FFR (uCT-FFR [version 1.5, United-Imaging Healthcare, Shanghai, China]). Performance characteristics of uCT-FFR and CTA in detecting lesion-specific ischemia in all lesions, intermediate lesions (luminal stenosis 30% to 70%), and "gray zone" lesions (FFR 0.75 to 0.80) were calculated with invasive FFR as the reference standard. The effect of coronary calcification on uCT-FFR measurements was also assessed. RESULTS: Per vessel sensitivities, specificities, and accuracies of 0.89, 0.91, and 0.91 with uCT-FFR, 0.92, 0.34, and 0.55 with CTA, and 0.94, 0.37, and 0.58 with invasive coronary angiography, respectively, were found. There was higher specificity, accuracy, and AUC for uCT-FFR compared with CTA and qualitative invasive coronary angiography in all lesions, including intermediate lesions (p < 0.001 for all). No significant difference in diagnostic accuracy was observed in the "gray zone" range versus the other 2 lesion groups (FFR ≤0.75 and >0.80; p = 0.397) and in patients with "gray zone" versus FFR ≤0.75 (p = 0.633) and versus FFR >0.80 (p = 0.364), respectively. No significant difference in the diagnostic performance of uCT-FFR was found between patients with calcium scores ≥400 and <400 (p = 0.393). CONCLUSIONS: This novel computational fluid dynamics-based CT FFR approach demonstrates good performance in detecting lesion-specific ischemia. Additionally, it outperforms CTA and qualitative invasive coronary angiography, most notably in intermediate lesions, and may potentially have diagnostic power in gray zone and highly calcified lesions.

15.
Front Neurosci ; 13: 763, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31404153

RESUMO

Objective: To explore the relationship among serum uric acid (SUA) levels in different states of disease, human cognition, and spontaneous brain activities by resting-state functional MRI (rs-fMRI). Methods: We prospectively recruited 100 subjects (age 58 ± 11 years, 55 females) who underwent fasting blood sampling, cognitive tests and rs-fMRI scans. The subjects were divided into two groups by sex and each sex group was further stratified into three subgroups according to SUA level in different states of disease. The amplitude of low-frequency fluctuation (ALFF) method was applied to assess spontaneous brain activity among groups. Pearson's correlation analysis was used to investigate the relationships between the mean ALFF values (mALFF) and cognitive tests. Results: A total of 97 patients completed the study protocol successfully. Significant differences in age, education level, number connection test (NCT), and word fluency were observed among the three subgroups in males (all P < 0.05). Results of group-by-sex interaction were distributed in bilateral pallidum and putamen [voxel P-value < 0.001, cluster P-value < 0.05, Gaussian random field (GRF)-corrected]. The tendency of the SUA effect on mALFF was different in males and females, particularly in corresponding High SUA subgroups (that is pre-hyperuricemia, both P < 0.001). Among the male subjects, mALFF values of the bilateral pallidum and putamen negatively correlated with attention/executive function. Conclusion: Our results suggest that elevated SUA levels have different effects on spontaneous brain activities and cognitive function in males and females. Males with pre-hyperuricemia and hyperuricemia are more susceptible to changes in spontaneous brain activities and lower neuropsychological assessment scores, particularly in word fluency tests and NCT, compared to females.

16.
Eur J Radiol ; 117: 69-74, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31307655

RESUMO

PURPOSE: To investigate the protective effect of oral Vitamin C on DNA double-strand breaks (DSBs) after abdominal contrast-enhanced CT examination. MATERIALS AND METHODS: Sixty patients undergoing abdominal multiphase contrast-enhanced CT were divided into control group (n = 30) and prevention group (n = 30). Patients in the prevention group were orally administered 1 g Vitamin C 30-120 minutes prior to CT examination. Blood samples were obtained prior to and 5 min following CT examination for each subject. γ-H2AX foci representing DSBs in the nucleus of lymphocytes were marked by fluorescent markers. Change in γ-H2AX foci/cell was compared through Student t-tests or ANOVA testing. The relationship between physical parameters and increase in γ-H2AX foci was analyzed through Pearson or Spearman correlation analysis. RESULTS: The mean increase in γ-H2AX was 0.49 foci /cell in the control group and 0.19 foci/cell in the prevention group (p < 0.001), corresponding to a 61% reduction in the mean increase in γ-H2AX foci in the prevention group compared to the control group. In the prevention group, increase in γ-H2AX foci/cell positively correlated with dose length product and volume CT dose index (r = 0.449 and 0.403, respectively; both p < 0.05). No difference in the increase in γ-H2AX foci/cell was found between the different time interval subgroups of 30, 60, and 120 min between Vitamin C administration and CT examination (p > 0.05). CONCLUSION: Oral Vitamin C can significantly reduce the level of DSBs after abdominal contrast-enhanced CT examination and is a simple and effective method to decrease DNA damage.


Assuntos
Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/farmacologia , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Profilaxia Pré-Exposição , Radiografia Abdominal/efeitos adversos , Tomografia Computadorizada por Raios X/efeitos adversos , Idoso , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Dano ao DNA , Relação Dose-Resposta à Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Adulto Jovem
17.
Eur J Radiol ; 116: 90-97, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31153580

RESUMO

PURPOSE: To evaluate the diagnostic performance of coronary computed tomography angiography derived fractional flow reserve (CT-FFR) with invasive fractional flow reserve (FFR) in patients with coronary artery disease" before "with invasive fractional flow reserve serving as the reference standard. MATERIALS AND METHODS: CT-FFR values based on a machine learning algorithm (cFFRML) in 183 vessels of 136 patients from four centers were measured with invasive FFR as reference standard. The diagnostic performance from our multicenter study was combined into a meta-analysis following a literature search in Web of Science, PubMed, Cochrane library to identify studies comparing diagnostic performance of coronary computed tomography angiography (CCTA) and CT-FFR. Sensitivity, specificity, accuracy were analyzed on both per-vessel and per-patient basis for intermediate lesions and by algorithm. RESULTS: Our multicenter study demonstrated sensitivities, specificities, and accuracies of cFFRML and CCTA of 0.85, 0.94, 0.90, and 0.95, 0.28, 0.55 on a per-vessel basis, respectively. For our meta-analysis, pooled sensitivities, specificities, and accuracies of CT-FFR and CCTA were 0.85, 0.82, 0.82, and 0.85, 0.57, 0.65 with AUC of 0.86 (95%CI: 0.83˜0.89) and 0.83 (95%CI: 0.79˜0.86) on a per-vessel basis, respectively. The sensitivity, specificity and accuracy for intermediate lesions using cFFRML were 0.84, 0.92, and 0.89. No significant difference was found among different algorithms of CT-FFR (P < 0.001). CONSLUSION: This multicenter study with meta-analysis showed that CT-FFR had a high diagnostic accuracy in determining ischemia-specific lesions and intermediate lesions. There was no significant difference when comparing the combined diagnostic performance of different algorithms of CT-FFR with invasive FFR as the reference standard.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/fisiopatologia , Algoritmos , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Feminino , Humanos , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/etiologia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
18.
Korean J Radiol ; 20(6): 894-908, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31132815

RESUMO

Kidney transplantation is the treatment of choice for patients with end-stage renal disease, as it extends survival and increases quality of life in these patients. However, chronic allograft injury continues to be a major problem, and leads to eventual graft loss. Early detection of allograft injury is essential for guiding appropriate intervention to delay or prevent irreversible damage. Several advanced MRI techniques can offer some important information regarding functional changes such as perfusion, diffusion, structural complexity, as well as oxygenation and fibrosis. This review highlights the potential of multiparametric MRI for noninvasive and comprehensive assessment of renal allograft injury.

19.
Eur J Radiol ; 113: 140-147, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30927938

RESUMO

PURPOSE: To develop institutional diagnostic reference levels (IDRL) for coronary CT angiography (CCTA) according to patient size by analyzing radiation dose changes over the past 10 years. MATERIALS AND METHODS: This IRB approved retrospective investigation analyzed radiation dose data from CCTA between 2007 and 2016 at our institution. Annual trends in radiation dose were described for each scanner type and scanning mode. Radiation levels were analyzed for normorhythmic patients, patients with prior coronary artery bypass grafting (CABG), arrhythmia, and according to patient size and tube voltage. Median, and quartile values for volume CT dose index (CTDIvol), dose-length product (DLP), and size-specific dose estimate (SSDE) were calculated. Wilcoxon rank-sum test and Kruskal Wallis test were performed to assess the significance of quantitative data. RESULTS: 35,375 examinations from 33,317 patients (median age, 58 [50-66] years; male patients, 21,087 [58.7%]) were analyzed. CTDIvol, DLP, and SSDE significantly decreased by 9.0%, 30.8%, and 40.1% (all P < 0.05) for all examinations, respectively. All radiation dose metrics progressively decreased across scanning modes (especially retrospectively ECG-gated spiral and prospectively ECG-triggered high-pitch spiral acquisition mode), but did not significantly change across scanners in the last 6 years. CTDIvol and DLP increased with patient size when water-equivalent diameters were >19 cm for normorhythmic and CABG patients. In arrhythmic patients, CTDIvol increased progressively with water-equivalent diameters across all groups. CONCLUSION: CCTA radiation dose has progressively decreased in the past decade except in patients with prior CABG and arrhythmia. Size-specific IDRLs may optimize radiation utilization in these patients going forward.


Assuntos
Angiografia por Tomografia Computadorizada/tendências , Angiografia Coronária/tendências , Idoso , Arritmias Cardíacas/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/normas , Tomografia Computadorizada de Feixe Cônico/normas , Tomografia Computadorizada de Feixe Cônico/tendências , Angiografia Coronária/normas , Ponte de Artéria Coronária/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Valores de Referência , Estudos Retrospectivos , Estatísticas não Paramétricas
20.
Eur Radiol ; 29(10): 5577-5589, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30937591

RESUMO

PURPOSE: This study was conducted in order to investigate the topological organization of functional and structural brain networks in diabetic kidney disease (DKD) and its potential clinical relevance. METHODS: Two hundred two subjects (62 DKD patients, 60 diabetes mellitus [DM] patients, and 80 healthy controls) underwent laboratory examination, neuropsychological test, and magnetic resonance imaging (MRI). Large-scale functional and structural brain networks were constructed and graph theoretical network analyses were performed. The effect of renal function on brain functional and structural networks in DKD patients was further evaluated. Correlations were performed between network properties and neuropsychological scores and clinical variables. RESULTS: Progressing deteriorated global and local network topology organizations (especially for functional network) were observed for DKD patients compared with control subjects (all p < 0.05, Bonferroni-corrected), with intermediate values for the patients with DM. DKD patients showed normally appearing functional-structural coupling compared with controls, while DM patients manifested functional-structural decoupling (p < 0.05, Bonferroni-corrected). Impaired kidney function markedly affected functional and structural network organization in DKD patients (all p < 0.05). Urea nitrogen correlated with global and local efficiency in the structural networks (r = - 0.551, p < 0.001; r = - 0.476, p < 0.001, respectively). Global and local efficiency in the structural networks and normalized characteristic path length in the functional networks were associated with information processing speed and/or psychomotor speed. CONCLUSION: DKD patients showed enhanced functional and structural brain network disruption and normally appearing functional-structural coupling compared with DM patients, which correlated with kidney function, renal toxins, and cognitive performance. KEY POINTS: • DKD patients showed markedly disrupted functional and structural brain network efficiency measures compared with DM patients and healthy controls. • Reduced kidney function clearly deteriorated functional and structural brain networks in DKD patients. • DKD patients displayed normally appearing functional-structural coupling compared with DM patients.


Assuntos
Nefropatias Diabéticas/fisiopatologia , Vias Neurais/fisiopatologia , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Mapeamento Encefálico/métodos , Estudos de Casos e Controles , Nefropatias Diabéticas/diagnóstico por imagem , Nefropatias Diabéticas/psicologia , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Testes Neuropsicológicos
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