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Mutant superoxide dismutase 1 (SOD1) may form cyclic structures due to its greater instability from aberrant demetallization and oxidation of cysteine bonds. This cyclic structure may allow SOD1 to form ion channels on membranes such as the mitochondrial membrane, causing imbalances in the concentration of intracellular ions as a potential mechanism for the progressive neuron death involved in amyotrophic lateral sclerosis (ALS). Using docking programs within modeling software, models of mutant SOD1 dimers and eventually ring oligomers were constructed based on known descriptions of such structures in addition to information on the orientation of the models associated with a membrane. The resulting structure consists of a ring of four demetallated mutant SOD1 dimers with cross-linked disulfide bonds. Stability of the octamer model was supported by the molecular dynamics simulations. Further analysis of the octamer model indicated that its inner- and outer-pore diameters were stable, matching the dimensions of known SOD1 ion channels.

Authors: Valentina L. Kouznetsova, Caroline Kellogg, Aidan Zhang, Mahidhar Tatineni, Mark A. Miller, Igor F. Tsigelny Background: SARS-CoV-2 has caused tens of millions of infections worldwide and millions of deaths. Currently, no effective treatment has been identified against the virus. Of its viral proteins, the RNA-dependent RNA polymerase (RdRp) is a promising target for drug design because of its importance in the replication of the virus. Material and Methods: After the identification of an RdRp pocket site based on the crystal structure of the RdRp– nsp7–nsp8 complex and the triphosphate form of remdesivir (PDB ID: 7BV2), we created a pharmacophore model consisting of 11 different features. These features include two acceptors, three donors, one acceptor and donor, three donor or acceptor, and one hydrophobic; an excluded volume of R=1.1 Å was also added. We then ran a pharmacophore search on our conformational database (DB) of approximately 2500 FDA-approved drugs and 600 000 conformations to identify potential drug-candidates. To determine the drugs that bound the best, we conducted multi conformational docking of these results to the previously identified pocket site. Results: The pharmacophore search found 315 different potential inhibitors of RdRp, of which 85 were chosen based on the number of H-bonds and hydrophobic interactions in the best docking pose. Several of the drugs selected, including ritonavir, dasatinib, imatinib, and sofosbuvir, have previously been shown to be effective against other viruses. Conclusions: These findings highlight compounds that could lead to both in vitro and in vivo studies to identify potential treatments against SARS-CoV-2.

Design methods for digital jacquard fabrics that employ equivalent increases or decreases in the number of weaving points in shaded-weave databases cannot display images with differing lightness effects. In this study, a design method for weave databases was proposed with a hierarchical combination based on the uniform segmentation of fabric lightness effects. A 16-end three-step sateen was used as the base weave for equivalent transition and hierarchical combination weave databases, which were used for the design of a single-layer black-and-white jacquard fabric. A comparative study of the simulative effects of fabric samples indicated that the shaded-weave database with a hierarchical combination design enabled adjustment of the colour rendering effect of the fabric. This approach improves the design flexibility and applicability of the database and provides a technical reference for further colour simulation and innovative colour design for digital jacquard fabrics.

Shaded weaves are used in digital jacquard fabrics for expressing rich colors, especially in the design of figured jacquard fabrics. The original image process and shaded weave database ( SWD) process are two independent design processes for the production of figured jacquard fabrics. SWD processes are relatively fixed, but original images vary frequently, and color value inconsistencies between the original image and its jacquard fabric are often neglected by researchers. This paper presents the design principles of a SWD based on a sateen basic weave and analyzes the color rendering of seven groups of fabric specimens produced using SWD processes with three transition directions and different step numbers. The color rendering characteristics of the SWD process were mainly determined by the transition direction of the interlacing points, but were also slightly affected by the weave’s step number when horizontal transitions were used. Three photographic images with different tones were selected to design three groups of single-layer figured jacquard fabrics. The results proved that the tone of a woven fabric is determined by the SWD process used, not the original image. A method was proposed to predict the final tone of a woven fabric by adjusting the lightness value of the original image according to the values of the fabric specimens of the SWD process that are used. This study outlines how the digital processing of a figured jacquard fabric design may be achieved using a SWD process based on one of the three design directions.

This study was aimed to determine Gastrodin (GAS) and its underlying signaling pathway involved in suppression of inflammasome specifically in reactive astrocytes that are featured prominently in different neurological conditions or diseases including cerebral ischemia. For this purpose, TNA2 astrocytes in cultures were exposed to oxygen–glucose–deprivation (OGD) mimicking hypoxic cerebral ischemia. Separately, TNA2 cells were pretreated with GAS prior to OGD exposure. Additionally, Stattic, an inhibitor of STAT3 signaling pathway, was used to ascertain its involvement in regulating inflammasome in astrocytes exposed to OGD. In parallel to the above, adult rats subjected to middle cerebral artery occlusion (MCAO) with or without GAS pretreatment were sacrificed at different time points to determine the effects of GAS on astrocyte inflammasome. TNA2 astrocytes in different treatments as well as reactive astrocytes in MCAO were processed for immunofluorescence labeling and Western blot analysis for various protein markers. In the latter, protein expression levels of p-STAT3, NLRP3, and NLRC4 were markedly increased in TNA2 astrocytes exposed to OGD. Remarkably, the expression levels of these biomarkers were significantly suppressed by GAS. Of note, GAS especially at dose 20 μM inhibited NLRP3 and NLRC4 expression levels most substantially. Moreover, GAS inhibited the downstream proteins caspase-1 and IL-18. Concomitantly, GAS significantly suppressed the expression of STAT3 and NF-κB signaling pathway. It is noteworthy that Stattic at dose 100 μM inhibited STAT3 pathway and NF-κB activation in TNA2 astrocytes, an effect that was shared by GAS. In MCAO, GAS was found to effectively attenuate p-STAT3 immunofluorescence intensity in reactive astrocytes. Arising from the above, it is concluded that GAS is anti-inflammatory as it effectively suppresses inflammasome in OGD-stimulated astrocytes as well as in reactive astrocytes in MCAO via STAT3 and NF-κB signaling expression coupled with decreased expression of caspase-1 and IL-18.

Brain damage, including blood-brain barrier (BBB) dysfunction, neurological behavior deficit, cerebral infarction and inflammation, is commonly caused by ischemic-reperfusion (I/R) injury. Prevention of the above biological process defects is considered beneficial for patient recovery after I/R injury. This study was aimed to assess the neuroprotective effect of Gastrodin (GAS), an herbal agent, in experimentally induced cerebral ischemia. Sprague-Dawley adult rats were randomly divided into six groups: Sham-operated control group (Sham), middle cerebral artery occlusion (MCAO) group, GAS (50, 100, and 200 mg/kg) pretreatment + MCAO groups (GAS) and Nimodipine (NIM) + MCAO, namely, the NIM group. Additionally, an OGD/R model using BV-2 microglia was established in vitro to simulate I/R injury. We showed here that the neurological scores of rats in the GAS groups were significantly improved compared with the MCAO group. Moreover, the area of cerebral infarction in the GAS pretreatment groups and the NIM group was significantly reduced. Furthermore, Evans blue leakage volume was significantly reduced with GAS pretreatment notably at dose 100 mg/kg. Expression of matrix metalloproteinase 2 (MMP2) and MMP9 in GAS groups was markedly decreased when compared with MCAO group. In BV-2 microglia exposed to OGD/R given GAS pretreatment, MMP2 and MMP9 positive cells were reduced in numbers. The present results have shown that GAS pretreatment significantly compensated for neurological behavior defects in rats with I/R-induced injury, reduced brain infarction size, reversed BBB impairment, and attenuated inflammation. It is suggested that pretreatment with GAS before surgery is beneficial during recovery from I/R injury.