Subdural effusion associated with COVID-19 encephalopathy: A case report.

BACKGROUND: The precise mechanism by which severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) impacts the central nervous system remains unclear, with manifestations spanning from mild symptoms (e.g., olfactory and gustatory deficits, hallucinations, and headache) to severe complications (e.g., stroke, seizures, encephalitis, and neurally demyelinating lesions). The occurrence of single-pass subdural effusion, as described below, is extremely rare. CASE SUMMARY: A 56-year-old male patient presented with left-sided limb weakness and slurred speech as predominant clinical symptoms. Through comprehensive imaging and diagnostic assessments, he was diagnosed with cerebral infarction complicated by hemorrhagic transformation affecting the right frontal, temporal, and parietal regions. In addition, an intracranial infection with SARS-CoV-2 was identified during the rehabilitation process; consequently, an idiopathic subdural effusion developed. Remarkably, the subdural effusion underwent absorption within 6 d, with no recurrence observed during the 3-month follow-up. CONCLUSION: Subdural effusion is a potentially rare intracranial complication associated with SARS-CoV-2 infection.

[Effect of Bone Marrow Mesenchymal Stem Cells on Mechanical Dynamics and BALP/CTX-1 Expression in Rats with Osteoporotic Vertebral Fracture].

Objective: To analyze the effects of bone marrow mesenchyml stem cells (BMSCs) on bone alkaline phosphatase (BALP)/C-terminal telopeptide of type-Ⅰ collagen (CTX-1) expression and mechanical dynamics in rats with osteoporotic (OP) vertebral fracture. Methods: A total of 60 female Sprague-Dawley rats were evenly divided into three groups, a control group that received sham operation (sham group), a group consisting of rats with OP vertebral fracture (OP group), and the last group consisting of OP vertebral fracture rats given BMSCs treatment (BMSCs group). Comparison of the three groups of animals was made in terms of bone dynamic change, bone quantitative broadband ultrasound attenuation (BUA) measurement, and bone mineral density (BMD). HE staining was done to examine the bone histological morphological parameters of the vertebral body. Serum CTX-1 and BALP levels were determined by ELISA. Results: Mechanical comparison showed that there were significant differences in mechanical changes of L 5 vertebra body and right femur among the three experimental groups ( P<0.05). The elastic modulus and maximum load of the OP group significantly decreased compared with those of the sham group ( P<0.05). After the intervention, the maximum load and elastic modulus of the BMSCs group were significantly higher than those of the OP group ( P<0.05). Compared with the sham group, BUA and BMD values in the OP group were significantly downregulated ( P<0.05). After intervention, BUA and BMD of the BMSCs group were significantly higher than those of the OP group and were comparable to those of the sham group ( P<0.05). Compared with the sham group, the number of trabeculae in the OP group was significantly fewer, and the distribution of trabeculae was disorderly and lacked regularity. Compared with the OP group, there were more trabeculae in the BMSCs group, and their distribution was more regular. Compared with sham group, bone histological morphological parameters of the vertebral body of rats in the OP group were significantly changed--mean trabecular plate thickness (MTPT) and trabecular bone volume (TBV) parameters were significantly decreased, while mineral apposition rate (MAR) and trabecula bone surface (TRS) parameters were significantly upregulated (all P<0.05). After the experimental intervention, bone histological morphological parameters of the vertebral body in the BMSCs group showed significant improvement compared with those of the OP group ( P<0.05). Compared with the sham group, serum BALP content in the OP group was greatly decreased, while the CTX-1 level was upregulated ( P<0.05). After the intervention, the BMSCs group had higher serum BALP content than that of the OP group and substantially lower CTX-1 content than that of the OP group ( P<0.05). Conclusion: BMSCs can improve the mechanical changes in rats with OP vertebral fracture, and can increase the maximum load and elastic modulus of bone tissue. In addition, BMSCs can upregulate the expression of BALP in serum and downregulate the expression of CTX-1, thus helping rats with OP vertebral fracture heal early.

Potential of antibody pair targeting conserved antigenic sites in diagnosis of SARS-CoV-2 variants infection.

Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 has become disaster for human society. As the pandemic becomes more regular, we should develop more rapid and accurate detection methods to achieve early diagnosis and treatment. Antigen detection methods based on spike protein has great potential, however, it has not been effectively developed, probably due to the torturing conformational complexity. By utilizing cross-blocking data, we clustered SARS-CoV-2 receptor binding domain (RBD)-specific monoclonal antibodies (mAbs) into 6 clusters. Subsequently, the antigenic sites for representative mAbs were identified by RBDs with designed residue substitutions. The sensitivity and specificity of selected antibody pairs was demonstrated using serial diluted samples of SARS-CoV-2 S protein and SARS-CoV S protein. Furthermore, pseudovirus system was constructed to determine the detection capability against SARS-CoV-2 and SARS-CoV. 6 RBD-specific mAbs, recognizing different antigenic sites, were identified as potential candidates for optimal antibody pairs for detection of SARS-CoV-2 S protein. By considering relative spatial position, accessibility and conservation of corresponding antigenic sites, affinity and the presence of competitive antibodies in clinical samples, 6H7-6G3 was rationally identified as optimal antibody pair for detection of both SARS-CoV-2 and SARS-CoV. Furthermore, our results showed that 6H7 and 6G3 effectively bind to SARS-CoV-2 variants of concern (VOCs). Taken together, we identified 6H7-6G3 antibody pair as a promising rapid antigen diagnostic tool in containing COVID-19 pandemic caused by multiple VOCs. Moreover, our results also provide an important reference in screening of antibody pairs detecting antigens with complex conformation.

Metabolomics-Based Pharmacodynamic Analysis of Zhuang Yao Shuang Lu Tong Nao Granules in a Rat Model of Ischemic Cerebral Infarction.

This study used a metabolomic approach to reveal changes in the levels of metabolic biomarkers and related metabolic pathways before and after Zhuang Yao Shuang Lu Tong Nao granule (YHT) treatment in rats with cerebral ischemia. The neurological deficit scores were significantly higher in the MCAO_R group than in the NC group, indicating that the mice had significantly impaired motor functions. The YHT group had significantly lower scores than the MCAO_R group, suggesting that YHT significantly improved motor function in rats. TTC staining of the brain tissue revealed that YHT significantly reduced the area of cerebral infarction in the treated rats. The MCAO_R group was better separated from the NC rent, sham, and YHT groups via metabolomic PCA. Moreover, there were significant differences in the differential metabolites between the MACO_R and YHT groups. Eighteen common differential metabolites were detected between the MACO_R and NC groups, MACO_R and sham groups, and MACO_R and YHT groups, indicating that YHT significantly increased the levels of various metabolites in the serum of cerebral ischemic stroke (CIS) rats. Moreover, a total of 23 metabolic pathways were obtained. We identified 11 metabolic pathways with the most significant effects in the bubble plots. In conclusion, from a systems biology perspective, this metabolomics-based study showed that YHT could be used to treat ischemic stroke by modulating changes in endogenous metabolites.

Synthesis of AG@AgCl Core-Shell Structure Nanowires and Its Photocatalytic Oxidation of Arsenic (III) Under Visible Light.

Ag@AgCl core-shell nanowires were synthesized by oxidation of Ag nanowires with moderate FeCl3, which exhibited excellent photocatalytic activity for As(III) oxidation under visible light. It was proved that the photocatalytic oxidation efficiency was significantly dependent on the mole ratio of Ag:AgCl. The oxidation rate of As(III) over Ag@AgCl core-shell nanowires first increased with the decrease of Ag0 percentage, up until the optimized synthesis mole ratio of Ag nanowires:FeCl3 was 2.32:2.20, with 0.023 mg L-1 min-1 As(III) oxidation rate; subsequently, the oxidation rate dropped with the further decrease of Ag0 percentage. Effects of the pH, ionic strength, and concentration of humic acid on Ag@AgCl photocatalytic ability were also studied. Trapping experiments using radical scavengers confirmed that h+ and ·O2- acted as the main active species during the visible-light-driven photocatalytic process for As(III) oxidation. The recycling experiments validated that Ag@AgCl core-shell nanowires were a kind of efficient and stable photocatalyst for As(III) oxidation under visible-light irradiation.

Efficiently Visible-Light Driven Photoelectrocatalytic Oxidation of As(III) at Low Positive Biasing Using Pt/TiO2 Nanotube Electrode.

A constant current deposition method was selected to load highly dispersed Pt nanoparticles on TiO2 nanotubes in this paper, to extend the excited spectrum range of TiO2-based photocatalysts to visible light. The morphology, elemental composition, and light absorption capability of as-obtained Pt/TiO2 nanotubes electrodes were characterized by FE-SEM, energy dispersive spectrometer (EDS), X-ray photoelectron spectrometer (XPS), and UV-vis spectrometer. The photocatalytic and photoelectrocatalytic oxidation of As(III) using a Pt/TiO2 nanotube arrays electrode under visible light (λ > 420 nm) irradiation were investigated in a divided anode/cathode electrolytic tank. Compared with pure TiO2 which had no As(III) oxidation capacity under visible light, Pt/TiO2 nanotubes exhibited excellent visible-light photocatalytic performance toward As(III), even at dark condition. In anodic cell, As(III) could be oxidized with high efficiency by photoelectrochemical process with only 1.2 V positive biasing. Experimental results showed that photoelectrocatalytic oxidation process of As(III) could be well described by pseudo-first-order kinetic model. Rate constants depended on initial concentration of As(III), applied bias potential and solution pH. At the same time, it was interesting to find that in cathode cell, As(III) was also continuously oxidized to As(V). Furthermore, high-arsenic groundwater sample (25 m underground) with 0.32 mg/L As(III) and 0.35 mg/L As(V), which was collected from Daying Village, Datong basin, Northern China, could totally transform to As(V) after 200 min under visible light in this system.