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Introduction Previous fMRI studies revealed that the abnormal functional connectivity (FC) was related to cognitive impairment in patients with SLE. However, it remains unclear how the disease severity affects the functional topological organization of the whole-brain network in SLE patients without neuropsychiatric symptoms (non-NPSLE). Objective We aim to examine the impairment of the whole-brain functional network in SLE patients without neuropsychiatric symptoms (non-NPSLE), which may improve the understanding of neural mechanism in SLE. Methods We acquired resting-state fMRI data from 32 non-NPSLE patients and 32 healthy controls (HC), constructed their whole-brain functional network, and then estimated the topological properties including global and nodal parameters by using graph theory. Meanwhile, we also investigated the differences in intra- and inter-network FC between the non-NPSLE patients and the HC. Results The non-NPSLE patients showed significantly lower clustering coefficient, global and local efficiency, but higher characteristic path length than the HC. The non-NPSLE patients had significantly lower nodal strength in two regions, ventromedial prefrontal cortex (vmPFC) and anterior PFC (aPFC) than the HC. We found the non-NPSLE patients had significantly lower intra-network FC within frontal-parietal network (FPN) and within default mode network (DMN), and significantly lower inter-network FC between DMN and FPN than the HC. The intra-network FC within DMN was negatively correlated with systemic lupus erythematosus disease activity index (SLEDAI). Conclusion Abnormal whole-brain functional network properties and abnormal intra- and inter-network FC may be related to cognitive impairment and disease degree in the non-NPSLE patients. Our findings provide a network perspective to understand the neural mechanisms of SLE.

The blood-brain barrier (BBB) damage has traditionally been considered to determine the occurrence and development of post-stroke brain edema, a devastating and life-threatening complication. However, no treatment strategy targeting BBB damage has been proven clinically effective in ameliorating brain edema. Here, we found that the extravasation of protein-rich fluids into the brain was not temporally correlated with edema formation after middle cerebral artery occlusion (MCAO) in mice, as brain edema reabsorption preceded BBB closure. Strikingly, the time course of edema progression matched well with the glymphatic system (GS) dysfunction after MCAO. Pharmacological enhancement of the GS function significantly alleviated brain edema developed on day 2 after MCAO, accompanied by less deposition of Aβ and better cognitive function. Conversely, functional suppression of the GS delayed the absorption of brain edema on day 7 after MCAO. Moreover, patients with ischemic stroke revealed a consistent trend of GS dysfunction after reperfusion as MCAO mice, which was correlated with the severity of brain edema and functional outcomes. Collectively, these findings indicate that the GS is a key contributor to the formation of brain edema after ischemic stroke, and targeting the GS may be a promising strategy for the treatment of brain edema in ischemic stroke.One Sentence SummaryThe function of the glymphatic system is a key factor in determining the formation or resolution of brain edema after ischemic strokeGraphical Abstract

Background To explore the impact of thoracic endovascular aortic repair (TEVAR) on aortic remodeling (AR) and the relationship between AR and complications after TEVAR. Methods A total of 56 patients (2 type IIIA aortic dissection [AD] and 54 type IIIB AD) with complicated acute type B aortic dissection suitable for TEVAR were prospectively enrolled. There were 44 men (78%) and 12 women (22%) with an average age of 54 ± 13.8 years. Aortic enhanced computed tomography (CT) was performed pre-TEVAR and 3, 6, and 12 months postoperatively. The morphological changes in AR, namely aortic volume and false lumen thrombosis, were obtained by analyzing the CT data. The effect of TEVAR on AR was determined by the morphological changes in the aorta. The relationship between AR index, false lumen thrombosis, and complications was analyzed. Results The volume of the thoracic aortic true lumen gradually increased post-TEVAR, whereas the volume of the thoracic aortic false lumen gradually decreased. The volume of abdominal aortic total lumen and false lumen increased 6 months postoperatively. The AR index increased significantly 3 months postoperatively, which was negatively correlated with complications and mortality. The thoracic and abdominal aortic false lumen thrombosis developed gradually after TEVAR, and the degree of thoracic aortic false lumen thrombosis was negatively correlated with complications and mortality. Conclusions TEVAR promotes AR. AR index and the degree of thoracic aortic false lumen thrombosis can serve as predictors of complications and mortality.

Rationale and Objectives The purpose of this study was to explore conventional MRI features that can accurately differentiate central nervous system embryonal tumor, not otherwise specified (CNS ETNOS) from glioblastoma (GBM) in adults. Materials and Methods Preoperative conventional MRI images of 30 CNS ETNOS and 98 GBMs were analyzed by neuroradiologists retrospectively to identify valuable MRI features. Five blinded neuroradiologists independently reviewed all these MRI images, and scored MRI features on a five-point scale. Kendall's coefficient of concordance was used to measure inter-rater agreement. Diagnostic value was assessed by the area under the curve (AUC) of receiver operating curve, and sensitivity and specificity were also calculated. Results Seven MRI features, including isointensity on T1WI, T2WI, and FLAIR, ill-defined margin, severe peritumoral edema, ring enhancement, and broad-based attachment sign, were helpful for the differential diagnosis of these two entities. Among these features, ring enhancement showed the highest inter-rater concordance (0.80). Ring enhancement showed the highest AUC value (0.79), followed by severe peritumoral edema (0.67). The combination of seven features showed the highest AUC value (0.86), followed by that of three features (ill-defined margin, severe peritumoral edema, and ring enhancement) (0.83). Conclusion Enhancement pattern, peritumoral edema, and margin are valuable for the discrimination between CNS ETNOS and GBM in adults.

OBJECTIVE: To investigate the abnormalities in regional homogeneity of brain activity in patients with diabetic peripheral neuropathy (DPN) using resting-state functional magnetic resonance imaging (rs-fMRI) and explore the association between brain activity changes and DPN. METHODS: A regional homogeneity (ReHo) approach was used to compare the local synchronization of rs-fMRI signals among 20 patients with painful DPN, 16 patients with painless DPN, and 16 type 2 diabetic patients without DPN (non-DPN group). RESULTS: Compared with the those without DPN, the patients with painful DPN showed high ReHo in the left inferior temporal gyrus and the right central posterior gyrus, and low ReHo in the posterior cingulate gyrus, right inferior parietal gyrus, and the left superior parietal gyrus (P < 0.05);the patients with painless DPN group showed high ReHo in the left inferior temporal gyrus, the right middle temporal gyrus, and the right superior frontal gyrus, and low ReHo in the left thalamus (P < 0.05).No significant differences in ReHo were found between the patients with painful DPN and painless DPN (P>0.05). CONCLUSION: The patients with DPN have altered ReHo in multiple brain regions and impairment of a default mode network, for which the left temporal gyrus may serve as a functional compensatory brain area. ReHo disturbance in the central right posterior gyrus may play a central role in the pain symptoms associated with painful DPN.

Wilms' tumor (WT) is the most common kidney tumor of children. The transformation suppressor gene RECK, which codes membrane-anchored glycoprotein, frequently downregulates multiple matrix metalloproteinases in tumors. And curcumin, which is a polyphenlic compound separated from turmeric, has antitumor effects on various cancers. However, the correlation of WT, RECK and curcumin is still unrevealed. In this study, we evaluated that the methylation degree of RECK was much higher in WT than in adjacent non-tumor tissues. And RECK methylation was closely associated with tumor metastasis in WT patients. After curcumin treatment, the level of RECK methylation was decreased significantly. And the expression of MMP2 and MMP9 was reduced consequently. Moreover, the proliferation, invasion and migration ability of WT cells were suppressed after curcumin treatment. Meanwhile, the apoptosis rate of WT cells was increased simultaneously. In nude mice model, curcumin restrained ability of tumorigenicity and promoted apoptosis of WT cells. Together, our results suggest that the RECK methylation can serve as a prognostic biomarker of WT. Moreover, curcumin could inhibit RECK methylation, thereby abates the expression of MMPs, and suppresses the tumor progression and metastasis of WT.

Quantitative susceptibility mapping (QSM) is a magnetic resonance imaging technique that quantifies the magnetic susceptibility distribution within biological tissues. QSM calculates the underlying magnetic susceptibility by deconvolving the tissue magnetic field map with a unit dipole kernel. However, this deconvolution problem is ill-posed. The morphology enabled dipole inversion (MEDI) introduces total variation (TV) to regularize the susceptibility reconstruction. However, MEDI results still contain artifacts near tissue boundaries because MEDI only imposes TV constraint on voxels inside smooth regions. We introduce a Morphology-Adaptive TV (MATV) for improving TV-regularized QSM. The MATV method first classifies imaging target into smooth and nonsmooth regions by thresholding magnitude gradients. In the dipole inversion for QSM, the TV regularization weights are a monotonically decreasing function of magnitude gradients. Thus, voxels inside smooth regions are assigned with larger weights than those in nonsmooth regions. Using phantom and in vivo datasets, we compared the performance of MATV with that of MEDI. MATV results had better visual quality than MEDI results, especially near tissue boundaries. Preliminary brain imaging results illustrated that MATV has potential to improve the reconstruction of regions near tissue boundaries.

Nitroxides have great potential as magnetic resonance imaging (MRI) contrast agents for tumor detection. Polyacetylenes(PAs) containing 2,2,6,6-tetramethyl-piperidine oxyl (TEMPO) and poly(ethylene glycol) were synthesized via metathesis polymerization of the corresponding substituted acetylenes to be used for targeted bimodal MRI /optical imaging of tumors. The poly(ethylene glycol) in the polyacetylenes enables covalent conjugation of carboxyl fluorescein and folic acid (FA) with hydroxyl groups to develop targeted multifunctional organic radical contrast agents (ORCAs). In vitro studies confirm the excellent binding specificity and subsequent enhanced cellular internalization of the targeted ORCAs (PA-TEMPO-FI-FA) without cytotoxicity. In vivo T1-weighted MRI demonstrates the active tumor targeting ability of PA-TEMPO-FI-FA to generate specific contrast enhancement in mice bearing HeLa tumors. Moreover, longitudinal optical imaging displays high tumor accumulation after 1 h post-injection of PA-TEMPO-FI-FA. These results indicate that multifunctional ORCAs may provide a tumor-targeted delivery platform for further molecular imaging guided cancer therapy.

The nucleus accumbens (NAc), an important target of deep brain stimulation for some neuropsychiatric disorders, is thought to be involved in epileptogenesis, especially the shell portion. However, little is known about the exact parcellation within the NAc, and its structural abnormalities or connections alterations of each NAc subdivision in temporal lobe epilepsy (TLE) patients. Here, we used diffusion probabilistic tractography to subdivide the NAc into core and shell portions in individual TLE patients to guide stereotactic localization of NAc shell. The structural and connection abnormalities in each NAc subdivision in the groups were then estimated. We successfully segmented the NAc in 24 of 25 controls, 14 of 16 left TLE patients, and 14 of 18 right TLE patients. Both left and right TLE patients exhibited significantly decreased fractional anisotropy (FA) and increased radial diffusivity (RD) in the shell, while there was no significant alteration in the core. Moreover, relatively distinct structural connectivity of each NAc subdivision was demonstrated. More extensive connection abnormalities were detected in the NAc shell in TLE patients. Our results indicate that neuronal degeneration and damage caused by seizure mainly exists in NAc shell and provide anatomical evidence to support the role of NAc shell in epileptogenesis. Remarkably, those NAc shell tracts with increased connectivities in TLE patients were found decreased in FA, which indicates disruption of fiber integrity. This finding suggests the regeneration of aberrant connections, a compensatory and repair process ascribed to recurrent seizures that constitutes part of the characteristic changes in the epileptic network.

To detect the abnormal cortical thickness and disrupted brain resting-state functional connectivity (RSFC) in patients with systemic lupus erythematosus (SLE) without neuropsychiatric symptoms (non-NPSLE). Using T1-weighted 3D brain structural data, we first determined the regions with abnormal cortical thickness in a cohort of 33 adult female non-NPSLE patients. By taking brain regions with significantly reduced cortical thickness as the seeds, we calculated their RSFC based on the resting-fMRI data and detected the relationship between the RSFC and cortical thickness in the non-NPSLE patients. Compared to the controls, the non-NPSLE patients showed significantly cortical thinning in the left fusiform gyrus (FUS.L), left lingual gyrus (LING.L), right lingual gyrus (LING.R) and left superior frontal cortex (SFC.L). As for the RSFC, statistical analyses indicated that the abnormal cortical thickness in LING.L is associated with increased RSFC in the left posterior cingulate cortex (PCC.L), and cortical thinning in SFC.L associated with decreased RSFC in left cerebellum 6 (CRBL 6.L) in non-NPSLE patients. In addition, in non-NPSLE patients, the decreased cortical thickness in LING.L was correlated to the increased RSFC in PCC.L, and decreased cortical thickness in SFC.L was correlated to the decreased RSFC in CRBL 6.L. Our findings suggest that the cortical abnormalities may affect brain intrinsic connectivity in non-NPSLE patients.

Previous neuroimaging studies have revealed cognitive dysfunction in patients with systemic lupus erythematosus (SLE) and suggested that it may be related to disrupted brain white matter (WM) connectivity. However, no study has examined the topological properties of brain WM structural networks in SLE patients, especially in patients with non-neuropsychiatric SLE (non-NPSLE). In this study, we acquired DTI datasets from 28 non-NPSLE patients and 24 healthy controls, constructed their brain WM structural networks by using a deterministic fiber tracking approach, estimated the topological parameters of their structural networks, and compared their group differences. We reached the following results: 1) At the global level, the non-NPSLE patients showed significantly increased characteristic path length, normalized clustering coefficient and small-worldness, but significantly decreased global efficiency and local efficiency compared to the controls; 2) At the nodal level, the non-NPSLE patients had significantly decreased nodal efficiency in regions related to movement control, executive control, and working memory (bilateral precentral gyri, bilateral middle frontal gyri, bilateral inferior parietal lobes, left median cingulate gyrus and paracingulate gyrus, and right middle temporal gyrus). In addition, to pinpointing the injured WM fiber tracts in the non-NPSLE patients, we reconstructed the major brain WM pathways connecting the abnormal regions at the nodal level with the corticospinal tract (CST), superior longitudinal fasciculus-parietal terminations (SLFP), and superior longitudinal fasciculus-temporal terminations (SLFT). By analyzing the diffusion parameters along these WM fiber pathways, we detected abnormal diffusion parameters in the bilateral CST and right SLFT in the non-NPSLE patients. These results seem to indicate that injured brain WM connectivity exists in SLE patients even in the absence of neuropsychiatric symptoms.

SummaryPurpose The objective of this study was to compare the clarity of magnetic resonance lymphography (MRL) images of the thoracic duct (TD) obtained from subjects following an overnight fast with those obtained from the same subjects after ingestion of a high fat meal. Methods Nineteen healthy volunteers were included in this study. TD images were acquired on a 3·0T MRI system with the imaging sequence of magnetic resonance cholangiopancreatography. TD MRL images were obtained from subjects following an overnight fast and from the same subjects 3–4 h after ingestion of a high fat meal. Images were displayed in maximum intensity projection format and degree of visualization was evaluated using a scoring system. Results The mean TD score obtained following an overnight fast was significantly lower than the mean TD score obtained 3–4 h after ingestion of a high fat meal (P

Objective To help surgeons to locate the intracranial anatomic landmarks when performing endoscopic endonasal tanssphenoidal surgery using measurements based on three-dimensional computed tomography (CT) reconstruction images. Method High-resolution axial CT images at the thickness of 0.6 mm, and reconstructed 0.41-mm-thick gapless sagittal and coronal CT images were taken from 111 subjects. Using mimics software, first located the points of nasal spine, midpoint of the posterior hard palate and the basic line between them. Then located the medial edge of foramen lacerums, optic canals, midpoints of tuberculum sellae and posterior-inferior sellar floor, measured their distances to nasal spine and angles between the line connecting these structures to nasal spine and the basic line. Results The mean distance from nasal spine to optic canal is 73.12 ± 4.10 mm, and the corresponding angle is 39.79° ± 3.13°. The distance from the medial edge of foramen lacerum to nasal spine is 79.91 ± 4.01 mm, and the corresponding angle is 23.27° ± 2.89°. The distances from midpoints of the tuberculum sellae and posterior-inferior sellar floor to nasal spine are 76.16 ± 4.56 mm and 82.05 ± 4.81 mm, and the corresponding angles are 34.97° ± 3.24° and 26.39° ± 3.51°, respectively. The distances between both foramen lacerums and optic canals are 22.54 ± 3.25 and 23.44 ± 3.49 mm, respectively. The distance from the midpoint of tuberculum sellae to posterior-inferior sellar floor is 13.33 ± 1.87 mm. Conclusion The current study provides information about intracranial anatomic landmarks, which can help neurosurgeons to locate them and avoid relative complications during endoscopic endonasal transsphenoid surgery. The measurements can be used as surgical indicators to investigate these anatomic landmarks.

To evaluate the diagnostic performance of five MR sequences to detect pulmonary infectious lesions in patients with invasive fungal infection (IFI), using multidetector computed tomography (MDCT) as the reference standard. Thirty-four immunocompromised patients with suspected IFI underwent MDCT and MRI. The MR studies were performed using five pulse sequences at 3.0 T: T2-weighted turbo spin echo (TSE), short-tau inversion recovery (STIR), spectrally selective attenuated inversion recovery (SPAIR), T1-weighted high resolution isotropic volume excitation (e-THRIVE) and T1-weighted fast field echo (T1-FFE). The size, lesion-to-lung contrast ratio and the detectability of pulmonary lesions on MR images were assessed. Image quality and artefacts on different sequences were also rated. A total of 84 lesions including nodules (n = 44) and consolidation (n = 40) were present in 75 lobes. SPAIR and e-THRIVE images achieved high overall lesion-related sensitivities for the detection of pulmonary abnormalities (90.5 % and 86.9 %, respectively). STIR showed the highest lesion-to-lung contrast ratio for nodules (21.8) and consolidation (17.0), whereas TSE had the fewest physiological artefacts. MRI at 3.0 T can depict clinically significant pulmonary IFI abnormalities with high accuracy compared to MDCT. SPAIR and e-THRIVE are preferred sequences for the detection of infectious lesions of 5 mm and larger. • A radiation-free radiological method is desirable for assessing pulmonary infectious lesions • MRI at 3 T can depict lung infiltrates with good concordance to MDCT • SPAIR and e-THRIVE are favourable sequences for the detection of pulmonary lesions • The greatest benefit is for the diagnosis of lesions larger than 5 mm