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Rationale and objective: To investigate the MR characteristics of phlegmonous stage and abscess stage primary spinal epidural abscess. Materials and methods: This study retrospectively analyzed the clinical and imaging characteristics of 27 cases of pathologically confirmed primary spinal epidural abscess. Predisposing conditions of all patients were collected. All patients underwent conventional magnetic resonance imaging, while fifteen patients also underwent post-contrast magnetic resonance imaging. Results: The initial symptoms included back pain in 25 patients, fever in 18, motor deficit in five, and sensory changes in 13. Underlying diseases included distant site of infection in seven, injection therapy in five, neoplasm in five, chronic inflammatory disease in five, diabetes mellitus in four, alcoholism in three, metabolic disorder in three, hepatopathy in three, and obesity in two. Abscess location was ventral epidural space in 15 patients (55.6%) and dorsal epidural space in 12 (44.4%). On T1-weighted image, the abscess was hypointense to the spinal cord in 23 patients (85%) and isointense in four (15%). All abscesses were hyperintense to the spinal cord on T2-weighted image. Among the 15 patients who underwent contrast-enhanced imaging, ring enhancement was present in 13 and homogeneous enhancement in two. Adjacent vertebrae body edema was present in four patients. The abscess was purely intraspinal in 25 patients (92.6%). Paraspinal extension was present in two (7.4%). Conclusion: Primary spinal epidural abscess patients have one or more predisposing conditions. Phlegmonous stage primary spinal epidural abscess appears isointense on T1WI and hyperintense on T2WI and enhancement is homogeneous. Abscess stage primary spinal epidural abscess hyperintense on T2WI and hypointense on T1WI and ring enhancement. Presence of vertebral body edema is an important sign to help diagnose primary spinal epidural abscess. [ABSTRACT FROM AUTHOR]

Objective: To analyze the mechanism of action and compatibility of the active compounds of the traditional herb pair Bupleuri Radix (Chai Hu, CH, 柴胡) - Paeoniae Radix Alba (Bai Shao, BS, 白芍). Methods: All chemical compounds related to CH and BS were retrieved from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP), Traditional Chinese Medicine Integrated Database (TCMID), Bioinformatics Analysis Tool for Molecular mechANism of Traditional Chinese Medicine (Batman-TCM), Traditional Chinese Medicine Database@Taiwan (TCM Database@Taiwan), and the literature. Relevant compounds were screened for oral bioavailability (OB), drug-likeness (DL), and the Caco-2 cell model. The Uniprot, Genecard, and CTD databases were used to obtain information on potential targets and diseases of associated compounds. Based on this, Cytoscape 3.2.1 software, GO enrichment analysis, and KEGG pathway enrichment were used to analyze the potential mechanism of action and pathways of the CH - BS drug combination. Results: A total of 23 active compounds of CH and BS were indentified after meeting specific criteria by network pharmacology, showing 79 predicted targets of active compounds. Among them, all targets were associated with 344 diseases, and the compounds in CH and BS were connected to 94 pathways and biological, such as calcium signaling pathway, neuroactive ligand-receptor interaction and TNF signaling pathway. Conclusions: Our results preliminarily validated the main compounds in CH - BS herb pair interacted with multiple targets in different diseases, and the molecular mechanism of these compounds involves multiple pathways, thereby establishing a good foundation for further studies. Keywords: Bupleuri Radix (Chai Hu, 柴 胡), Paeoniae Radix Alba (Bai Shao, 白芍), Herb pair, Network pharmacology, Mechanism of action

The highly efficient Z-scheme photocatalyst Ag2CO3/Ag/g-C3N4 with Ag nanoparticles, as an electron mediator, was fabricated by a simple calcinations-precipitation reaction. Photocatalytic experiments of the as-prepared samples were tested by the photocatalytic oxidation degradation of RhB aqueous solution. The results show that Ag2CO3/Ag/g-C3N4 composites exhibit enhanced photocatalytic activity, compared with Ag2CO3 and g-C3N4. The composites exhibit the highest photocatalytic performance, when the mass ratio of g-C3N4 to Ag2CO3/Ag is 20%,which is attributed to the formation of Z-scheme heterojunction structure between Ag2CO3 and g-C3N4, thus accelerating electron transfer rate and separating efficiently the photo-generated electron-hole pairs. Meanwhile, the Z-scheme heterojunction structures extend the wavelength range of visible light absorption (from 450nm to 670nm) due to the surface plasma resonance (SPR) of Ag nanoparticles. The trapping experiment results confirm that·O2- and h+ are main active species,·OH plays a relatively minor role in the decomposition of RhB. A possible mechanism for enhanced photocatalytic activity of Ag2CO3/Ag/g-C3N4 heterojunction photocatalyst is proposed.

A compact frequency-selective surface (FSS) having a quasi-elliptic bandpass response is presented in this paper. This was realized by vertically cascading substrate integrated waveguide (SIW) cavities. A single SIW cavity FSS has been fully studied and approximate analytical formulas are introduced to calculate its resonant frequencies. Two different resonances can be excited by a plane wave in the single SIW cavity FSS. According to theories of the cascading cavity filter and dual-mode filter, cross coupling can be realized in cascading SIW cavity FSSs, thus a compact FSS with a quasi-elliptic bandpass response is implemented. A K a-band sample was fabricated by a printed circuit board (PCB) process. Experiments were carried out to validate this design method. Measured results are in agreement with predicted ones. The proposed quasi-elliptic FSS presents a number of advantages, namely, high selectivity, stable performance, and much reduced volume. Index Terms--Cascading cavities, dual-mode filter, frequency-selective surface (FSS), substrate integrated waveguide (SIW), quasi-elliptic.