Dual-energy computed tomography in the early evaluation of acute radiation pneumonia.

OBJECTIVE: To investigate the value of dual-energy dual-source computed tomography (DSCT) in evaluating pulmonary perfusion changes before and after radiotherapy for esophageal cancer, and its clinical use in the early diagnosis of acute radiation pneumonia (ARP). METHODS: We selected 45 patients with pathologically confirmed esophageal cancer who received radiotherapy (total irradiation dose of 60 Gy). Dual-energy DSCT scans were performed before and after radiotherapy and the normalized iodine concentrations (NIC) in the lung fields of the areas irradiated with doses of > 20 Gy, 10-20 Gy, 5-10 Gy, and < 5 Gy were measured. We also checked for the occurrence of ARP in the patients, and the differences in NIC values and NIC reduction rates before and after radiotherapy were calculated and statistically analyzed. RESULTS: A total of 16 of the 45 patients developed ARP. The NIC values in the lung fields of all patients decreased at different degrees after radiotherapy, and the NIC values in the area where ARP developed, decreased significantly. The rate of NIC reduction and incidence rate of ARP increased gradually with the increasing irradiation dose, and the inter-group difference in NIC reduction rate was statistically significant (P < 0.05). Based on the receiver operating characteristic (ROC) curve analysis, the areas under the curves of NIC reduction rate versus ARP occurrence in the V5-10 Gy, V10-20 Gy, and V> 20 Gy groups were 0.780, 0.808, and 0.772, respectively. Sensitivity of diagnosis was 81.3%, 75.0%, and 68.8% and the specificity was 65.5%, 82.8%, and 79.3%, when taking 12.50%, 16.50%, and 26.0% as the diagnostic thresholds, respectively. The difference in NIC values in the lung fields of V<5 Gy before and after radiotherapy was not statistically significant (P > 0.05). CONCLUSION: The dual-energy DSCT could effectively evaluate pulmonary perfusion changes after radiotherapy for esophageal cancer, and the NIC reduction rate was useful as a reference index to predict ARP and provide further reference for decisions in clinical practice.

Effects of Different Materials on Residual Stress Fields of Blade Damaged by Foreign Objects.

Foreign object damage (FOD) is a common mode of failure in high-speed rotating machinery, such as aircraft engines. Therefore, research on FOD is crucial for ensuring blade integrity. FOD induces residual stress on the surface and within the blade, impacting its fatigue strength and service life. Therefore, this paper utilizes material parameters determined by existing experiments, based on the Johnson-Cook (J-C) constitutive model, to numerically simulate impact damage inflicted on specimens, compare and analyze the residual stress distribution of impact pits, and investigate the influence law of foreign object characteristics on blade residual stress. TC4 titanium alloy, 2A12 aluminum alloy, and Q235 steel were selected as foreign objects, and dynamic numerical simulations of the blade impact process were performed to explore the effects of different types of metal foreign objects. This study analyzes the influence of different materials and foreign objects on the residual stress generated by blade impact through numerical simulation, examining the distribution of residual stress in different directions. The findings indicate that the generated residual stress increases with the density of the materials. Additionally, the geometry of the impact notch is also influenced by the density difference between the impact material and the blade. The distribution of the residual stress field reveals that the maximum residual tensile stress in the blade is related to the density ratio, and the residual tensile stress in the axial and circumferential direction is relatively large. It is important to note that a significant residual tensile stress has a detrimental effect on the fatigue strength.

The alterations of degree centrality in the frontal lobe of patients with panic disorder.

Objective: The brain network in panic disorder (PD) is still an intriguing issue for research. In this study, we hoped to investigate the role of DC (degree centrality) for the pathophysiology of PD, especially for the fear network. Methods: We enrolled 60 patients with PD and 60 controls in the current study. The gender and age were matched for two groups. All participants received the resting-state functional magnetic resonance imaging to survey the baseline brain activity. Then the DC values of all participants were using REST toolbox. We also compared the DC values between PD and controls. The statistical threshold was set as FDR (false discovery rate) < 0.05. Results: The DC values were significantly lower in the right superior frontal gyrus of PD patients compared to controls (FDR < 0.05). In addition, a negative correlation between the DC values and panic severity was observed in the right superior frontal gyrus and left inferior frontal gyrus. However, there was no significant association between the DC values and illness duration. Conclusion: The DC seemed significantly altered in the frontal lobe of PD patients. The role of the frontal lobe might be more emphasized in the pathophysiology research for PD.

Hsa_circ_0134111 promotes osteoarthritis progression by regulating miR-224-5p/CCL1 interaction.

Mechanical, metabolic, inflammatory, and immune factors contribute to the development of osteoarthritis (OA), a joint disease characterized by cartilage destruction. The circular RNA (circRNA) hsa_circ_0134111 is upregulated in the cartilage of OA patients; however, its potential role in OA pathogenesis and progression remains unexplored. In this study, the effects of hsa_circ_0134111 knockdown were evaluated in primary human chondrocytes treated with IL-1ß to simulate OA, as well as in a rat model of OA. Hsa_circ_0134111 expression was upregulated in IL-1ß-stimulated chondrocytes. CCK-8 and flow cytometry assays showed that hsa_circ_0134111 knockdown reversed IL-1ß-induced cell decline by inhibiting apoptosis. Following prediction analysis of circRNA and miRNA targets, dual-luciferase reporter and silencing/overexpression assays suggested that a regulatory network composed of hsa_circ_0134111, miR-224-5p, and CCL1 modulates IL-1ß-mediated OA-like effects in chondrocytes. Accordingly, CCL1 overexpression abrogated the prosurvival effects of hsa_circ_0134111 knockdown in vitro. Moreover, hsa_circ_0134111 silencing in vivo alleviated cartilage destruction in an OA rat model, decreased IL-6 and TNF-α levels in synovial fluid, and downregulated CCL1 expression in the affected joints. These results suggest that hsa_circ_0134111 contributes to OA development by binding to miR-224-5p, thereby releasing the inhibition that miR-224-5p exerts over CCL1.

Application of CT Imaging in the Diagnosis of Cerebral Hemorrhage and Cerebral Infarction Nerve Damage.

OBJECTIVE: This article analyzes computed tomography (CT) angiography and CT perfusion imaging parameters of patients with cerebral hemorrhage and cerebral infarction, and explores its diagnostic value and clinical significance in the diagnosis of cerebral hemorrhage and cerebral infarction. METHODS: This article selected 52 patients with ischemic cerebrovascular disease who were treated in our neurology department from January 2015 to December 2018. Twenty of these patients had transient ischemic attacks, and 32 had neurologic damage. According to the onset time, patients with cerebral infarction were divided into 12 cases in group A (onset time <6 hours) and 20 cases in group B (onset time >6 hours). CT perfusion imaging was performed within 24 hours after the onset of cerebral hemorrhage. Patients immediately underwent CT perfusion imaging in the cerebral infarction group, and recorded the CT perfusion imaging parameters to analyze the nerve damage. RESULTS: The results showed that among the 20 patients with cerebral hemorrhage, 14 cases had anterior circulation cerebral hemorrhage, and 6 cases had posterior circulation cerebral hemorrhage. No lesions were found on CT and magnetic resonance imaging. CT angiography of 20 patients with cerebral hemorrhage showed that 18 patients had vascular lesions. In the cerebral infarction group, 30 cases developed vascular disease. CONCLUSIONS: Studies have confirmed that changes in brain CT perfusion imaging parameters can reflect changes in brain blood perfusion to diagnose nerve damage, and mean transit time and time to peak are the most sensitive during the diagnosis. CT angiography can detect the degree of stenosis and has important clinical value for the etiology of cerebral hemorrhage and cerebral infarction.