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Synthesis of coronary 4D CT Image by denoising diffusion probabilistic model

2026-08-01T00:00:00Z

Title: Synthesis of coronary 4D CT Image by denoising diffusion probabilistic model Authors: Han, Tae Ho; Kim, Young Woo; Lee, Hyeong Jun; Kim, Jung-Sun; Lee, Seul-Gee; Yang, Dong Hyun; Oh, Hong Min; Kim, Doosang; Shin, Seung Yong; Song, Simon; Lee, Joon Sang Abstract: Purpose: Fluctuations in the pressure drop during the cardiac cycle can provide prognostic information for coronary artery disease (CAD). However, 4D computed tomography (CT) is required for time-variant flow analysis, which results in high doses of radiation exposure. In this study, we propose a novel diffusion-based framework for synthesizing physiologically consistent 4D CT images and performing 4D CT flow analysis. Methods: A denoising diffusion probabilistic model (DDPM) integrated with a deformation module was used for precise anatomical reconstruction. Subsequently, a computational fluid dynamics (CFD) model coupled with quasi-steady fluid-structure interaction (FSI) was utilized to calculate the 4D hemodynamic flow field. Results: The model achieved a peak signal-to-noise ratio of 32.01 and a structural similarity index measure of 0.937. After 3D construction and segmentation, the average Dice coefficient was 0.973. Furthermore, the computational fluid analysis was also performed with a fractional flow reserve (FFR) accuracy of 90.5%, demonstrating its efficacy in reducing radiation exposure without compromising diagnostic quality. Conclusion: Our results demonstrate that this synthesized 4D CT-based hemodynamic approach provides timevariant information for CAD diagnosis. This method offers valuable guidance for clinical decision-making as well as the possibility of prognostic information based on dynamic lumen evaluation.

Interplay of age-sensitive cortical vulnerability and dopaminergic degeneration in clinical manifestations of Parkinson's disease

2026-07-01T00:00:00Z

Title: Interplay of age-sensitive cortical vulnerability and dopaminergic degeneration in clinical manifestations of Parkinson's disease Authors: Kang, Sungwoo; Na, Han Kyu; Yoon, So Hoon; Kim, Han-Kyeol; Ryu, Young Hoon; Lee, Hye Sun; Yoo, Han Soo; Lyoo, Chul Hyoung; 유한수 Abstract: To identify the pattern of cortical atrophy variation in Parkinson's disease (PD) and its contribution to clinical manifestations beyond dopaminergic dysfunction, 45 healthy controls (HCs) underwent MRI, and 222 participants with PD additionally underwent dopamine transporter (DAT)-PET, Unified PD Rating Scale (UPDRS), and neuropsychological tests. Using principal component analysis in PD, a single pattern in cortical thickness (PC1PD) was identified. Linear regressions models were applied to investigate the effects of PC1PD and putaminal DAT (DAT-P) on parkinsonism, and PC1PD and caudate DAT (DAT-C) on cognition. PC1PD accounted for more than 80% of total cortical variance and showed a strong negative correlation with age. The spatial pattern of PC1PD was similar to that of PC1 derived from HCs, but its age-related association was more pronounced in PD. Independent of DAT-P, lower PC1PD was associated with higher UPDRS motor score and showed a synergistic significant interaction with DAT-P on the axial subscore. Independent of DAT-C, lower PC1PD was associated with worse performance in global cognition, language, and executive functions, with synergistic interaction with DATC on global cognition and executive function. The associations of PC1PD with UPDRS motor scores, general cognition, and executive function were stronger in older participants, indicating that aging amplifies the clinical effect of PC1PD. PC1PD represents an age-sensitive cortical vulnerability axis whose expression is amplified in PD, and its interplay with dopaminergic depletion and aging contributes to axial motor symptoms and executive dysfunction in PD.

Mechanisms underlying the effect of nurse-led enhanced supportive care for advanced cancer patients: A mediation analysis of randomized controlled trial data

2026-06-01T00:00:00Z

Title: Mechanisms underlying the effect of nurse-led enhanced supportive care for advanced cancer patients: A mediation analysis of randomized controlled trial data Authors: Hong, Bomi; Choi, Yun Young; Lee, Hye Sun; Lee, Jiyeon Abstract: Purpose: A nurse-led enhanced supportive care intervention integrating the Bandura's mastery enhancement and the acceptance and commitment therapy approach as an early primary palliative care was effective in improving coping, self-efficacy for coping with cancer, and role functioning. This study examined the mechanisms through which the intervention improved role functioning in patients with advanced cancer, focusing on the mediating roles of coping and self-efficacy for coping with cancer. Methods: A secondary analysis was conducted (N = 182). Active coping, self-efficacy for maintaining activity and independence, and role functioning were measured using the Brief COPE, the Cancer Behavior Inventory 3.0, and the EORTC QLQ-C30. Descriptive, correlation, and mediation analyses were conducted using IBM SPSS 27 and PROCESS macro Models 4 and 6. Results: In the serial mediation analysis, the intervention demonstrated statistically significant total effect on role functioning (effect = 8.89, SE = 3.21, 95% CI [2.54, 15.23]). The direct effect of the intervention remained significant after accounting for active coping and self-efficacy in maintaining activity and independence as mediators (effect = 6.19, SE = 3.08, 95% CI [0.12, 12.27]). The sequential pathway suggested by the conceptual model was statistically significant (effect = 0.78, SE = 0.46, 95% CI [0.11, 1.90]) and explained 8.8% of the total effect. Conclusion: The nurse-led enhanced supportive care improved role functioning via the serial mediation of active coping and self-efficacy for maintaining activity and independence. The results highlight the importance of coping and self-efficacy in enhancing role functioning and provide direction for future palliative care interventions. Trial registration: NCT04407013.

Association between dietary patterns and CAIDE-predicted dementia risk: A 20-year cohort of the Korean Genome and Epidemiology study

2026-05-01T00:00:00Z

Title: Association between dietary patterns and CAIDE-predicted dementia risk: A 20-year cohort of the Korean Genome and Epidemiology study Authors: Youn, Ji-Eun; Heo, Seok-Jae; Lee, Yae-Ji; Han, Tae-hwa; Kwon, Yu-Jin; Lee, Ji-Won Abstract: This study examined associations between dietary habits and the risk of developing Cardiovascular Risk Factors, Aging, and Incidence of Dementia (CAIDE)-predicted late-life dementia risk in Korean adults. A total of 5,042 participants aged 40-69 years were included. We assessed associations between dietary patterns-the Mediterranean diet, Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet, Korean Healthy Eating Index (KHEI), and Empirical Dietary Inflammatory Index (EDII)-and CAIDE-predicted high risk of dementia. Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated using Cox proportional hazards models, and cumulative incidence was assessed using Kaplan-Meier analysis. Longitudinal trajectories of CAIDE scores over a 10-year period were analyzed using linear mixed-effects models. During follow-up of 15.83 years, 30.9% progressed to CAIDE-predicted high risk of dementia. The highest tertile of the Mediterranean diet, MIND diet, and KHEI were associated with lower cumulative incidence (P = .008, P < .001, and P < .001) and reduced risk of progression to CAIDE-predicted high risk of dementia (HR 0.78, 95% CI 0.67-0.90, HR 0.80, 95% CI 0.69-0.93, and HR 0.80, 95% CI 0.70-0.91, respectively) along with lower CAIDE score (P < .001, P < .001, P = .002). Conversely, the highest EDII tertile showed the highest cumulative incidence (P < .001), an increased risk of progression to CAIDE-predicted high risk of dementia (HR 1.15, 95% CI 1.01-1.32), and elevated CAIDE scores (P < .001). Greater adherence to the Mediterranean diet, MIND diet, and KHEI, and lower consumption of pro-inflammatory diets were associated with a lower risk of high CAIDE-predicted late-life dementia and slower accumulation of risk factors.