Polarization-independent plasmon-induced transparency and slow light effects in a fully continuous symmetric cross-shaped monolayer graphene structure.

A fully continuous geometric center symmetric cross-shaped graphene structure is proposed. Each cross-shaped graphene unit cell is composed of a central graphene region and four completely symmetric graphene chips, where each graphene chip acts as both bright and dark modes simultaneously, while the central graphene region always acts as the bright mode. Through destructive interference, the structure can realize the single plasmon-induced transparency (PIT) phenomenon, where the optical responses are independent of the polarization direction of the linearly polarized light due to the symmetry of the structure. Combining numerical simulations with coupled mode theory (CMT) calculations, the modulation of the Fermi energy of graphene to the optical spectra is investigated. The results show that the spectra are blue shifted as the Fermi energy increases, and the absorption of the two absorption peaks is basically equal (48.7%) when the Fermi energy increases to 0.667 eV. Theoretical calculations show that the slow light performance of the designed structure enhances with the increase of Fermi energy, where the maximum group index is high up to 424.73. Furthermore, it is worth noting that the electrode can be made very small due to its fully continuous structure. This work provides guidance in terms of terahertz modulators, tunable absorbers, and slow light devices.

Taohong siwu decoction ameliorates cognitive dysfunction through SIRT6/ER stress pathway in Alzheimer's disease.

ETHNOPHARMACOLOGICAL RELEVANCE: A growing number of people suffer from Alzheimer's disease (AD), but there is currently no effective treatment yet. Taohong Siwu Decoction (TSD) has been proved to take strong neuropharmacological activity on dementia, but the effect and mechanism of TSD against AD are still elusive. AIM OF STUDY: To investigate whether TSD could be effective in ameliorating cognitive deficits through SIRT6/ER stress pathway. MATERIALS AND METHODS: Herein, the APP/PS1 mice, an AD model, and HT-22 cell lines were utilized. Different dosages of TSD (4.25, 8.50 and 17.00 g/kg/d) were administered to the mice for 10 weeks by gavage. Following the behavioral tests, oxidative stress levels were measured using malondialdehyde (MDA) and superoxide dismutase (SOD) kits. Nissl staining and Western blot analyses were used to detect the neuronal function. Then, immunofluorescence and Western blot analysis were applied to evaluate silent information regulator 6 (SIRT6) and ER Stress related protein levels in APP/PS1 mice and HT-22 cells. RESULTS: Behavioral tests revealed that APP/PS1 mice administered with TSD orally took more time in the target quadrant, crossed more times in the target quadrant, had a higher recognition coefficient, and spent more time in the central region. In addition, TSD could ameliorate oxidative stress and inhibit neuronal apoptosis in APP/PS1 mice. Furthermore, TSD could up-regulate the SIRT6 protein expression and inhibit ER sensing proteins expressions, such as p-PERK and ATF6, in APP/PS1 mice and Aß1-42-treated HT22 cells. CONCLUSION: According to the abovementioned findings, TSD could alleviate cognitive dysfunction in AD by modulating the SIRT6/ER stress pathway.

Hydroxysafflor Yellow A Exerts Neuroprotective Effect by Reducing Aß Toxicity Through Inhibiting Endoplasmic Reticulum Stress in Oxygen-Glucose Deprivation/Reperfusion Cell Model.

Ischemia stroke is thought to be one of the vascular risks associated with neurodegenerative diseases, such as Alzheimer's disease (AD). Hydroxysafflor yellow A (HSYA) has been reported to protect against stroke and AD, while the underlying mechanism remains unclear. In this study, SH-SY5Y cell model treated with oxygen-glucose deprivation/reperfusion (OGD/R) was used to explore the potential mechanism of HSYA. Results from cell counting kit-8 (CCK-8) showed that 10 µM HSYA restored the cell viability after OGD 2 hours/R 24 hours. HSYA reduced the levels of malondialdehyde and reactive oxygen species, while improved the levels of superoxide dismutase and glutathione peroxidase. Furthermore, apoptosis was inhibited, and the expression of brain-derived neurotrophic factor was improved after HSYA treatment. In addition, the expression levels of amyloid-ß peptides (Aß) and BACE1 were decreased by HSYA, as well as the expression levels of binding immunoglobulin heavy chain protein, PKR-like endoplasmic reticulum (ER) kinase pathway, and activating transcription factor 6 pathway, whereas the expression level of protein disulfide isomerase was increased. Based on these results, HSYA might reduce Aß toxicity after OGD/R by interfering with apoptosis, oxidation, and neurotrophic factors, as well as relieving ER stress.

Tanshinone IIA ameliorates Aß transendothelial transportation through SIRT1-mediated endoplasmic reticulum stress.

BACKGROUND: The disruption of blood-brain barrier (BBB), predominantly made up by brain microvascular endothelial cells (BMECs), is one of the characteristics of Alzheimer's disease (AD). Thus, improving BMEC function may be beneficial for AD treatment. Tanshinone IIA (Tan IIA) has been proved to ameliorate the cognitive dysfunction of AD. Herein, we explored how Tan IIA affected the function of BMECs in AD. METHODS: Aß1-42-treated brain-derived endothelium cells.3 (bEnd.3 cells) was employed for in vitro experiments. And we performed molecular docking and qPCR to determine the targeting molecule of Tan IIA on Sirtuins family. The APPswe/PSdE9 (APP/PS1) mice were applied to perform the in vivo experiments. Following the behavioral tests, protein expression was determined through western blot and immunofluorescence. The activities of oxidative stress-related enzymes were analyzed by biochemically kits. Nissl staining and thioflavin T staining were conducted to reflect the neurodegeneration and Aß deposition respectively. RESULTS: Molecular docking and qPCR results showed that Tan IIA mainly acted on Sirtuin1 (SIRT1) in Sirtuins family. The inhibitor of SIRT1 (EX527) was employed to further substantiate that Tan IIA could attenuate SIRT1-mediated endoplasmic reticulum stress (ER stress) in BMECs. Behavioral tests suggested that Tan IIA could improve the cognitive deficits in APP/PS1 mice. Tan IIA administration increased SIRT1 expression and alleviated ER stress in APP/PS1 mice. In addition, LRP1 expression was increased and RAGE expression was decreased after Tan IIA administration in both animals and cells. CONCLUSION: Tan IIA could promote Aß transportation by alleviating SIRT1-mediated ER stress in BMECs, which ameliorated cognitive deficits in APP/PS1 mice.

Sodium tanshinone IIA sulfonate improves cognitive impairment via regulating Aß transportation in AD transgenic mouse model.

Alzheimer's disease (AD) is a most common neurodegenerative disease. Sodium Tanshinone IIA Sulfonate (STS) has been reported to ameliorate AD pathology. However, the underlying mechanism is still unclear. In this study, AD transgenic mouse model (APP/PS1) was used to explore the potential mechanism of STS against AD. Morris water maze and Y-maze tests showed that administration of STS improved learning and memory abilities of APP/PS1 mice. STS reduced the levels of reactive oxygen species and malondialdehyde, while improved the activity of superoxide dismutase in both hippocampus and cortex in APP/PS1 mice. STS inhibited the activity of acetylcholinesterase, while improved the activity of choline acetyltransferase in APP/PS1 mice. In addition, STS elevated the protein expressions of neurotrophic factors and synapse-related proteins in both the hippocampus and cortex in APP/PS1 mice. At last, STS improved the protein expressions of glucose transporter 1 (GLUT1) and low-density lipoprotein receptor-related protein 1 (LRP1). These results indicated that the potential mechanism of STS on AD might be related to Aß transportation function via GLUT1/LRP1 pathway. HIGHLIGHTS: STS improves cognitive impairment of APP/PS1 mice. STS ameliorates the oxidative stress damage and improves the cholinergic system. STS protects against neuronal dysfunction and enhances the synaptic plasticity. STS mediates the Aß transportation of BMECs.

Predictive value on diffusion weighted imaging scores for basilar artery occlusion after endovascular treatment.

PURPOSE: To assess the predictive value of three scoring systems based on diffusion weighted imaging in basilar artery occlusion patients after endovascular treatment. METHODS: We analyzed clinical and radiological data of patients with basilar artery occlusion from January 2010 to June 2019, with modified Rankin Scale of 0-2 and 3-6 defined as favorable outcome and unfavorable outcome at three months. Diffusion weighted imaging posterior circulation ASPECTS Score (DWI pc-ASPECT Score), Renard diffusion weighted imaging Score, and diffusion weighted imaging Brainstem Score were used to evaluate the early ischemic changes. RESULTS: There were a total of 88 basilar artery occlusion patients enrolled in the study after endovascular treatment, with 33 of them getting a favorable outcome. According to the analysis, the time from onset to puncture within 12 h (odds ratio: 4.34; 95% confidence interval: 1.55-12.16; P = 0.01), presence of collateral flow via PCoA (odds ratio: 0.31; 95%CI: 0.12-0.79; P = 0.01) or between PICA and SCA (odds ratio: 0.18; 95%CI: 0.07-0.47; P = 0.00), equal or less than 15 points on baseline NIHSS (area under the curve 0.79, 95% CI 0.69-0.89; sensitivity = 69.1%, specificity = 81.8%; P = 0.00), and equal or less than 1.5 points on diffusion weighted imaging Renard score (area under the curve 0.63, 95% CI 0.51-0.75; sensitivity = 83.6%, specificity = 39.4%; P = 0.046) were independently associated with favorable outcome. CONCLUSIONS: Renard diffusion weighted imaging score may be an independent predictor of functional outcome in basilar artery occlusion patients after endovascular treatment.

Mild alkali-pretreatment effectively extracts guaiacyl-rich lignin for high lignocellulose digestibility coupled with largely diminishing yeast fermentation inhibitors in Miscanthus.

In this study, various alkali-pretreated lignocellulose enzymatic hydrolyses were evaluated by using three standard pairs of Miscanthus accessions that showed three distinct monolignol (G, S, H) compositions. Mfl26 samples with elevated G-levels exhibited significantly increased hexose yields of up to 1.61-fold compared to paired samples derived from enzymatic hydrolysis, whereas Msa29 samples with high H-levels displayed increased hexose yields of only up to 1.32-fold. In contrast, Mfl30 samples with elevated S-levels showed reduced hexose yields compared to the paired sample of 0.89-0.98 folds at p<0.01. Notably, only the G-rich biomass samples exhibited complete enzymatic hydrolysis under 4% NaOH pretreatment. Furthermore, the G-rich samples showed more effective extraction of lignin-hemicellulose complexes than the S- and H-rich samples upon NaOH pretreatment, resulting in large removal of lignin inhibitors to yeast fermentation. Therefore, this study proposes an optimal approach for minor genetic lignin modification towards cost-effective biomass process in Miscanthus.

The minor wall-networks between monolignols and interlinked-phenolics predominantly affect biomass enzymatic digestibility in Miscanthus.

Plant lignin is one of the major wall components that greatly contribute to biomass recalcitrance for biofuel production. In this study, total 79 representative Miscanthus germplasms were determined with wide biomass digestibility and diverse monolignol composition. Integrative analyses indicated that three major monolignols (S, G, H) and S/G ratio could account for lignin negative influence on biomass digestibility upon NaOH and H2SO4 pretreatments. Notably, the biomass enzymatic digestions were predominately affected by the non-KOH-extractable lignin and interlinked-phenolics, other than the KOH-extractable ones that cover 80% of total lignin. Furthermore, a positive correlation was found between the monolignols and phenolics at p<0.05 level in the non-KOH-extractable only, suggesting their tight association to form the minor wall-networks against cellulases accessibility. The results indicated that the non-KOH-extractable lignin-complex should be the target either for cost-effective biomass pretreatments or for relatively simply genetic modification of plant cell walls in Miscanthus.