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Purpose: To investigate the role of moderate doses of ionizing radiation-induced cellular senescence in mouse lung tissue and whole-body inflammation levels. Material and methods: Forty-two C57BL/6J mice were randomly divided into the control group, the 1, 3, and 7 days after 2 Gy irradiation group, and the 1, 3, and 7 days after 4 Gy irradiation group, with six mice in each group. The histopathology, cellular senescence, oxidative-antioxidant, DNA damage repair, and inflammation-related indicators of irradiated mice were examined. Results: Compared with the control group, the histopathological scores, the positive area of senescence-associated-β-galactosidase (SA-β-Gal) staining, and the mRNA levels of senescence-related genes in the lung tissues in all dose groups increased on 1, 3, and 7 days after irradiation. In peripheral blood, erythrocytes, leukocytes, platelets, hemoglobin, 8-hydroxydeoxyguanosine (8-OHdG), C-reactive protein, and other indicators showed a different trend in all dose groups. The levels of malondialdehyde(MDA), superoxide dismutase (SOD), glutathione (GSH), and 8-OHdG in the lung tissue showed different trends after 2 Gy and 4 Gy irradiation. The 8-Oxoguanine DNA glycosylase 1 (hOGG1) and O-6-methylguanine-DNA methyltransferase (MGMT) mRNA levels showed a trend of increasing and then decreasing. The levels of whole-body inflammation were significantly correlated with the levels of indicators related to cellular senescence and damage repair in the lung tissue of mice. Conclusions: The moderate doses of ionizing radiation induce oxidative stress, and DNA damage and increase DNA repair gene expression in mouse lung tissue. The lung tissue cellular senescence correlates with the level of whole-body inflammation. [ABSTRACT FROM AUTHOR]

Background: The Benton Judgment of Line Orientation (JLO) test is one of the most frequently used tests for assessing visuospatial function. Objective: This study aimed to determine the diagnostic and differential performance of JLO for different types of dementia. Methods: A total of 258 participants, including 68 patients with Alzheimer's disease (AD), 86 with subcortical ischemic vascular dementia (SIVD), 30 with frontotemporal lobar degeneration (FTLD), 22 with Lewy body dementia (LBD), and 52 cognitively unimpaired (CU) controls, were enrolled from a memory clinic. The total scores and error types in the JLO test were compared between groups. Receiver operating characteristic curve analyses were used to estimate the diagnostic and differential abilities of the JLO test for patients with different types of dementia. Results: We found that the JLO score was significantly lower in patients with AD, SIVD, FTLD, or LBD than in CU controls (12.90 ± 8.72 versus 17.06 ± 6.14 versus 15.47 ± 8.39 versus 9.23 ± 8.96 versus 21.69 ± 3.72, respectively; all p < 0.05). In particular, for patients with LBD, the JLO score was significantly lower than that for patients in the other groups (all p < 0.05) and showed excellent performance in distinguishing LBD patients from CU controls, with an AUC of 0.888 (sensitivity 72.73% and specificity 94.23%) at a cutoff value of 16. Intraquadrant oblique error was the most common type of error in dementia patients. Conclusions: The JLO test is an effective tool for evaluating visuospatial function in patients with dementia, particularly for identifying LBD patients. [ABSTRACT FROM AUTHOR]

The present study employed direct numerical simulation to investigate the supersonic flow of Mach 3 in a bent pipe with a curvature of 0.0825, elucidating the dynamic mechanism of secondary motions within the turbulent boundary layer. The findings indicate that the compressible flow, affected by the wall curvature, is differentiated into several motion patterns as the bending angle increases: a portion of the outer fluid close to the wall, driven by the circumferential pressure gradient, moves inward through the lateral wall, causing an increase in the mass rate toward the lateral boundary layer and promoting the circumferential transport of energy and vorticity; other outer fluids at the start of the bent section, due to the centrifugal force, approach the wall to form a thinner boundary layer downstream; meanwhile, the fluid near the inner wall experiences the expansion, followed by the flow separation and reattachment at a bending angle of 14.6° and 22.0°, respectively, which induce a shear layer that develops from the inner end point toward the mainstream center, gradually reshaping the high-speed flow area within the pipe cross section into a U-shape, and enhancing the vorticity and temperature field of the inner region. Additionally, this study reveals a remarkable phenomenon that the separated flow in a localized inner region forms a rotating field, inducing vortices distinct from the mainstream Dean vortices in the low-speed flow region enclosed by the shear layer. [ABSTRACT FROM AUTHOR]

The generation of turbulent inflow conditions is a key issue in large eddy simulation (LES) or direct numerical simulation (DNS). In this paper, an improved synthetic eddy method (SEM) is proposed to generate inflow turbulence for LES and DNS. The improvements about SEM focus on the eddy radius and eddy distributions. First, the eddy radius is improved to reduce the nonphysical vortex structure on the wall caused by overestimation of the radius. Second, a sampling method using Gaussian distribution is proposed to improve the distribution of eddies, which accurately captures the randomness of turbulent structure size and is close to the actual flow field. The improved method is applied to the direct numerical simulation of the supersonic turbulent boundary layer at Mach 2.7 and the 24° compression ramp. Results indicate that the predictions yielded by the improved method are in good agreement with both DNS and experimental data. Compared to the original method, the improved method exhibits a more rapid recovery of the friction coefficient and effectively shortens the development distances. The improved SEM has enhanced the efficiency and accuracy of generating inlet turbulence, which can provide inlet turbulence boundary conditions for LES and DNS. [ABSTRACT FROM AUTHOR]

Aims: To analyze the value of 18F‐fluorodeoxyglucose (FDG) positron emission tomography (PET) combined with amyloid PET in cognitive impairment diagnosis. Methods: A total of 187 patients with dementia or mild cognitive impairment (MCI) who underwent 11C‐Pittsburgh compound B (PiB) and FDG PET scans in a memory clinic were included in the final analysis. Results: Amyloid‐positive and amyloid‐negative dementia patient groups showed a significant difference in the proportion of individuals presenting temporoparietal cortex (p < 0.001) and posterior cingulate/precuneus cortex (p < 0.001) hypometabolism. The sensitivity and specificity of this hypometabolic pattern for identifying amyloid pathology were 72.61% and 77.97%, respectively, in patients clinically diagnosed with AD and 60.87% and 76.19%, respectively, in patients with MCI. The initial diagnosis was changed in 32.17% of patients with dementia after considering both PiB and FDG results. There was a significant difference in both the proportion of patients showing the hypometabolic pattern and PiB positivity between dementia conversion patients and patients with a stable diagnosis of MCI (p < 0.05). Conclusion: Temporoparietal and posterior cingulate/precuneus cortex hypometabolism on FDG PET suggested amyloid pathology in patients with cognitive impairment and is helpful in diagnostic decision‐making and predicting AD dementia conversion from MCI, particularly when combined with amyloid PET. [ABSTRACT FROM AUTHOR]

Cervical cancer (CC) is a common gynaecological malignant tumour with a high mortality rate. Circular RNAs (circRNAs) play a critical role in tumour occurrence and development. This study aimed to investigate the function and molecular basis of hsa_circ_0009189 (circSAMD11) in CC development. RNA levels were determined by qRT‐PCR, and protein expression was measured by western blot. Cell proliferation, migration, invasion and apoptosis were detected by Cell Counting Kit‐8 (CCK‐8), colony formation, Transwell and flow cytometry assays. The relationship between miR‐503 and circSAMD11/SOX4 was validated via dual‐luciferase reporter assay, RIP or RNA pull‐down assay. Xenograft assay was conducted to test tumour growth in vivo. CircSAMD11 and SOX4 levels were elevated, while miR‐503 level was reduced in CC tissues and cells. Knockdown of circSAMD11 suppressed CC cell proliferation, migration and invasion and accelerated apoptosis. CircSAMD11 was localised in cytoplasm and directly targeted miR‐503. Also, circSAMD11 sponged miR‐503 to modulate SOX4 expression. Additionally, circSAMD11 regulated CC progression via absorbing miR‐503 or modulating SOX4. Besides, depletion of circSAMD11 hindered tumorigenesis in vivo. CircSAMD11 contributed to CC progression by regulating miR‐503/SOX4 signalling and activating Wnt/β‐catenin pathway, which provides a promising therapeutic target for cervical cancer. [ABSTRACT FROM AUTHOR]