Diffusion-weighted imaging of the orbit.

Orbital lesions compose a heterogeneous group of pathologies that often present with non-specific imaging findings on conventional magnetic resonance imaging (MRI) sequences (T1-and T2-weighted). Accordingly, the application of diffusion MRI offers an opportunity to further distinguish between lesions along this spectrum. Diffusion-weighted imaging (DWI) represents the simplest and most frequent clinically utilised diffusion imaging technique. Recent advances in DWI techniques have extended its application to the evaluation of a wider spectrum of neurological pathology, including orbital lesions. This review details the manifestations of select orbital pathology on DWI and underscores specific situations where diffusion imaging allows for increased diagnostic sensitivity compared to more conventional MRI techniques. These examples also describe preferred management for orbital lesions identified by DWI.

Association of oxidative stress and Kashin-Beck disease integrated Meta and Bioinformatics analysis.

OBJECTIVE: To explore the association between oxidative stress (OS) and Kashin-Beck disease (KBD). METHODS: Terms associated with "KBD" and "OS" were searched in the six different databases up to October 2021. Stata 14.0 was used to pool the means and standard deviations using random-effect or fixed-effect model. The differentially expressed genes in the articular chondrocytes of KBD were identified, the OS related genes were identified by blasting with the GeneCards. The KEGG pathway and gene ontology enrichment analysis was conducted using STRING. RESULTS: The pooled SMD and 95% CI showed hair selenium (-4.59; -6.99, -2.19), blood selenium (-1.65; -2.86, -0.44) and glutathione peroxidases (-4.15; -6.97, -1.33) levels were decreased in KBD, whereas the malondialdehyde (1.12; 0.60, 1.64), nitric oxide (2.29; 1.31, 3.27), nitric oxide synthase (1.07; 0.81, 1.33) and inducible nitric oxide synthase (1.69; 0.62, 2.77) were increased compared with external controls. Meanwhile, hair selenium (-2.71; -5.32, -0.10) and glutathione peroxidases (-1.00; -1.78, -0.22) in KBD were decreased, whereas the malondialdehyde (1.42; 1.04, 1.80), nitric oxide (3.08; 1.93, 4.22) and inducible nitric oxide synthase (0.81; 0.00, 1.61) were elevated compared with internal controls. Enrichment analysis revealed apoptosis was significantly correlated with KBD. The significant biological processes revealed OS induced the release of cytochrome c from mitochondria. The cellular component of OS located in the mitochondrial outer membrane. CONCLUSIONS: The OS levels in KBD were significantly increased because of selenium deficiency, OS mainly occurred in mitochondrial outer membrane, released of cytochrome c from mitochondria, and induced apoptotic signaling pathway.

Transcriptome and metabolome analyses of the immune response to light stress in the hybrid grouper (Epinephelus lanceolatus ♂ × Epinephelus fuscoguttatus ♀).

Light intensity is an important environmental factor that affects fish growth and health through multiple physiological activities and metabolism and eventually impacts aquaculture harvest. There is a need to evaluate the fish stress response to light intensities, which will benefit aquaculture. Here, hybrid grouper (Epinephelus lanceolatus ♂ × Epinephelus fuscoguttatus ♀) was treated with three light intensities for evaluation of the light stress response, including high light intensity (1 250 lx), low light intensity (10 lx) and moderate light intensity (250 lx). Transcriptome analysis showed that a total of 71 318 unigene sequences were obtained with an N50 of 2 589 bp. Compared to the control group (250 lx), 1 697 differentially expressed genes (DEGs), a considerable quantity, were detected in the 1 250 lx group. Among those genes, 548 were upregulated, and the remaining 149 genes showed decreased expression. Comparatively small numbers of DEGs were detected in the 10 lx group; 54 out of 103 genes exhibited upregulated expression, and 49 genes showed downregulation. For further KEGG analysis, 82 DEGs were enriched in nine common signalling pathways in immunity, of which 73 DEGs were significantly inhibited in the 1 250 lx group. In contrast, only 11 DEGs were enriched in three immunity pathways, with nine DEGs showing a significant increase in the 10 lx group. The metabolome analysis revealed 59 and 44 differential metabolites (DMs) from the 1 250 lx and 10 lx groups, respectively. Of note, those DMs from the 1 250 lx-treated group were tendentiously involved in amino acid metabolism and lipid metabolism pathways, while the purine metabolism, amino acid metabolism and lipid metabolism pathways were mostly found in the 10 lx treatment group. In summary, our data indicated that high light intensity significantly inhibited the immune response in hybrid grouper, while low light intensity presented low stimulation of immune activity. In addition, both high and low light intensity could inhibit protein synthesis and amino acid metabolism. Taken together, hybrid grouper exhibited a much milder stress response to low light intensity than to high light intensity.

Associations between severe pulmonary function and residual CT abnormalities in rehabilitating COVID-19 patients.

OBJECTIVE: Coronavirus disease 2019 (COVID-19) spread around the world in 2020. Abnormal pulmonary function and residual CT abnormalities were observed in COVID-19 patients during recovery. Appropriate rehabilitation training is around the corner. The correlation between spirometric impairment and residual CT abnormality remains largely unknown. PATIENTS AND METHODS: A cross-sectional study conducted on the pulmonary function of 101 convalescent COVID-19 patients before discharge. Multivariate analysis was used to establish a scoring system to evaluate the spirometric abnormality based on residual chest CT. RESULTS: Lung consolidation area >25% and severe-type COVID-19 were two independent risk factors for severe pulmonary dysfunction. Besides, a scoring system was established. People scoring more than 12 points have more chances (17 times) to get severe pulmonary function impairment before discharge. CONCLUSIONS: For the first time, a chest CT characteristics-based grading system was suggested to predict the pulmonary dysfunction of COVID-19 patients during convalescence in this study. This study may provide suggestions for pulmonary rehabilitation.

[Application of regression discontinuity design in epidemiological research].

Regression discontinuity design (RDD) is a rigorous quasi-experimental method. Based on the randomness of the distribution of samples around the critical value, the data on both sides are used for regression respectively, so as to avoid the interference of potential confounding factors and provide strong evidence for the inference of causal correlation. This study introduces the RDD and its research progress, and expounds its application in detail combined with cases, in order to provide reference for the application of RDD in epidemiological research.

Alterations in the Magnetoencephalography Default Mode Effective Connectivity following Concussion.

BACKGROUND AND PURPOSE: Magnetoencephalography is sensitive to functional connectivity changes associated with concussion. However, the directional influences between functionally related regions remain unexplored. In this study, we therefore evaluated concussion-related magnetoencephalography-based effective connectivity changes within resting-state default mode network regions. MATERIALS AND METHODS: Resting-state magnetoencephalography was acquired for 8 high school football players with concussion at 3 time points (preseason, postconcussion, postseason), as well as 8 high school football players without concussion and 8 age-matched controls at 2 time points (preseason, postseason). Time-series from the default mode network regions were extracted, and effective connectivity between them was computed for 5 different frequency bands. The default mode network regions were grouped into anterior and posterior default mode networks. The combined posterior-to-anterior and anterior-to-posterior effective connectivity values were averaged to generate 2 sets of values for each subject. The effective connectivity values were compared using a repeated measures ANOVA across time points for the concussed, nonconcussed, and control groups, separately. RESULTS: A significant increase in posterior-to-anterior effective connectivity from preseason to postconcussion (corrected P value = .013) and a significant decrease in posterior-to-anterior effective connectivity from postconcussion to postseason (corrected P value = .028) were observed in the concussed group. Changes in effective connectivity were only significant within the delta band. Anterior-to-posterior connectivity demonstrated no significant change. Effective connectivity in the nonconcussed group and controls did not show significant differences. CONCLUSIONS: The unidirectional increase in effective connectivity postconcussion may elucidate compensatory processes, invoking use of posterior regions to aid the function of susceptible anterior regions following brain injury. These findings support the potential value of magnetoencephalography in exploring directional changes of the brain network following concussion.

MRI-Based Deep-Learning Method for Determining Glioma MGMT Promoter Methylation Status.

BACKGROUND AND PURPOSE: O6-Methylguanine-DNA methyltransferase (MGMT) promoter methylation confers an improved prognosis and treatment response in gliomas. We developed a deep learning network for determining MGMT promoter methylation status using T2 weighted Images (T2WI) only. MATERIALS AND METHODS: Brain MR imaging and corresponding genomic information were obtained for 247 subjects from The Cancer Imaging Archive and The Cancer Genome Atlas. One hundred sixty-three subjects had a methylated MGMT promoter. A T2WI-only network (MGMT-net) was developed to determine MGMT promoter methylation status and simultaneous single-label tumor segmentation. The network was trained using 3D-dense-UNets. Three-fold cross-validation was performed to generalize the performance of the networks. Dice scores were computed to determine tumor-segmentation accuracy. RESULTS: The MGMT-net demonstrated a mean cross-validation accuracy of 94.73% across the 3 folds (95.12%, 93.98%, and 95.12%, [SD, 0.66%]) in predicting MGMT methylation status with a sensitivity and specificity of 96.31% [SD, 0.04%] and 91.66% [SD, 2.06%], respectively, and a mean area under the curve of 0.93 [SD, 0.01]. The whole tumor-segmentation mean Dice score was 0.82 [SD, 0.008]. CONCLUSIONS: We demonstrate high classification accuracy in predicting MGMT promoter methylation status using only T2WI. Our network surpasses the sensitivity, specificity, and accuracy of histologic and molecular methods. This result represents an important milestone toward using MR imaging to predict prognosis and treatment response.

Localised grey matter atrophy in multiple sclerosis is network-based: a coordinate-based meta-analysis.

AIM: To test the network degeneration hypothesis in multiple sclerosis (MS) with a two-stage coordinate-based meta-analysis by: (1) characterising regional selectivity of grey matter (GM) atrophy and (2) testing for functional connectivity involving these regions. MATERIALS AND METHODS: Meta-analytic sources included 33 journal articles (1,666 MS patients and 1,269 healthy controls) with coordinate-based results from voxel-based morphometry analysis demonstrating GM atrophy. Mass univariate and multivariate coordinate-based meta-analyses were performed to identify a convergent pattern of GM atrophy and determine inter-regional co-activation (as a surrogate of functional connectivity), with anatomical likelihood estimation and functional meta-analytic connectivity modelling, respectively. RESULTS: Localised GM atrophy was demonstrated in the thalamus, putamen, caudate, sensorimotor cortex, insula, superior temporal gyrus, and cingulate gyrus. This convergent pattern of atrophy displayed significant inter-regional functional co-activations. CONCLUSION: In MS, GM atrophy was regionally selective, and these regions were functionally connected. The meta-analytic model-based results of this study are intended to guide future development of quantitative neuroimaging markers for diagnosis, evaluating disease progression, and monitoring treatment response.

The potential of induced pluripotent stem cells as a tool to study skeletal dysplasias and cartilage-related pathologic conditions.

The development of induced pluripotent stem cells (iPSCs) technology has opened up new horizons for development of new research tools especially for skeletal dysplasias, which often lack human disease models. Regenerative medicine and tissue engineering could be the next areas to benefit from refinement of iPSC methods to repair focal cartilage defects, while applications for osteoarthritis (OA) and drug screening have evolved rather slowly. Although the advances in iPSC research of skeletal dysplasias and repair of focal cartilage lesions are not directly relevant to OA, they can be considered to pave the way to future prospects and solutions to OA research, too. The same problems which face the present cell-based treatments of cartilage injuries concern also the iPSC-based ones. However, established iPSC lines, which have no genomic aberrations and which efficiently differentiate into extracellular matrix secreting chondrocytes, could be an invaluable cell source for cell transplantations in the future. The safety issues concerning the recipient risks of teratoma formation and immune response still have to be solved before the potential use of iPSCs in cartilage repair of focal cartilage defects and OA.

Evaluation of the therapeutic effect of treatment with intra-articular hyaluronic acid in knees for Kashin-Beck disease: a meta-analysis.

OBJECTIVE: To assess the efficacy and safety of intra-articular hyaluronic acid (IAHA) injection in knee joints of patients with Kashin-Beck disease (KBD). METHODS: We searched nine electronic databases as well as unpublished data from inception until November 30th 2013 using a combination of search terms for KBD and hyaluronic acid (HA). For dichotomous data, odds ratios (OR) and 95% confidence intervals (CI) were estimated. For continuous data, standard mean difference (SMD) was used for outcomes pooled on the difference scale using a "random-effects" or "fixed-effects" model. We also compared the mean and standard deviation of cytokine levels in post-treatment. RESULTS: The seven eligible trials included 954 IAHA and 495 control patients. The methodological quality of included trials was low. The overall effectiveness of the IAHA group and control group were 93.7% and 62.9%, respectively. IAHA group resulted in very large treatment effects compared to pre-treatment values in 12 months, with SMD values ranging from 1.19-2.64 (all P < 0.05). Compared to controls, SMDs in IAHA group ranged from 0.19-0.64 at 1 week to 1 month (all P > 0.05) and 0.68-1.47 at 2 months to 12 months (all P < 0.05). There was significant improved of HA, cluster of differentiation44 (CD44), keratan sulfate (KS), interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α) and nitric oxide (NO) contents in serum compared with that in the post-treatment and healthy control in non-KBD area (all P < 0.05). CONCLUSION: IAHA for the treatment of KBD was safe and efficacious at 12 months with low and transient adverse reactions. However, more high-quality randomized controlled trials (RCTs) are needed to confirm its therapeutic effect.