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Despite using effective drugs and vaccines for Covid 19, due to some limitations of current strategies and the high rate of coronavirus mutation, the development of medicines with effective inhibitory activity against this infection is essential. The SARS-CoV-2 enters the cell by attaching its receptor-binding domain (RBD) of Spike to angiotensin-converting enzyme-2 (ACE2). According to previous studies, the natural peptide Urtica dioica agglutinin (UDA) exhibited an antiviral effect on SARS-CoV, but its mechanism has not precisely been elucidated. Here, we studied the interaction between UDA and RBD of Spike protein of SARS-CoV-2. So, protein-protein docking of RBD-UDA was performed using Cluspro 2.0. To further confirm the stability of the complex, the RBD-UDA docked complex with higher binding affinity was studied using Molecular Dynamic simulation (via Gromacs 2020.2), and MM-PBSA calculated the binding free energy of the system. In addition, ELISA assay was used to examine the binding of UDA with RBD protein. Results were compared to ELISA of RBD-bound samples of convalescent serum IgG (from donors who recovered from Covid 19). Finally, the toxicity of UDA is assessed by using MTT assay. The docking results show UDA binds to the RBD binding site. MD simulation illustrates the UDA-RBD complex is stable during 100 ns of simulation, and the average binding energy was calculated to be -47.505 kJ/mol. ELISA and, MTT results show that UDA binds to RBD like IgG-RBD binding and may be safe in human cells. Data presented here indicate UDA interaction with S-protein inhibits the binding sites of RBD, it can prevent the virus from attaching to ACE2 and entering the host cell.

Sleep is involved in maintaining energy, regulating heat, and recovering tissues. Furthermore, proper cognitive functions need sufficient sleep. Many studies have revealed the impairment effect of sleep deprivation (SD) on cognitive functions including learning and memory. Alpha lipoic acid (ALA) is a potent free radical scavenger, biological antioxidant, and neuroprotective agent. Furthermore, ALA improves learning and memory performance, decreases oxidative stress, and enhances antioxidant biomarkers. In this study, we aimed to investigate the effect of ALA on social interaction and passive avoidance memories in sleep-deprived rats. Total sleep deprivation (TSD) apparatus was used to induce SD (for 24 h). Three-chamber paradigm test and shuttle box apparatus were used to evaluate social interaction and passive avoidance memory, respectively. Rats’ locomotor apparatus was used to assess locomotion. ALA was administered intraperitoneally at doses of 17 and 35 mg/kg for 3 consecutive days. The results showed SD impaired both types of memories. ALA at the dose of 35 mg/kg restored social interaction memory in sleep-deprived rats; while, at the dose of 17 mg/kg attenuated impairment effect of SD. Moreover, ALA at the dose of 35 mg/kg impaired passive avoidance memory in sham-SD rats and at both doses did not rescue passive avoidance memory in sleep-deprived rats. In conclusion, ALA showed impairment effect on passive avoidance memory, while improved social interaction memory in sleep-deprived rats.

In this work, ultrathin nickel films are developed for application as transparent electrodes in thermoelectric devices. The quality of the films is determined systematically by electrical, optical, and morphological characterization in a series of samples with different thickness. The thermal properties of the films show a dramatic dependence of the Seebeck coefficient on the film thickness. This dependence, with values ranging from −16 to +5 𝜇V K−1 for thicknesses from 10 to 2 nm, includes a change in the behavior of the thermoelectric response from n- to p-type. It has also been demonstrated that the accurate estimation of the thermal conductivity in thin films is challenging due to substrate effects. In this situation, a differential measurement method based on scanning thermal microscopy is proposed, as in these conditions the measurements are less sensitive to the substrate effects. In further works, the dependence of the thermal properties of ultrathin nickel films can be exploited as a tuning parameter for the design of thermoelectric devices.

Aggregation of the TAU proteins in the form of neurofibrillary tangles (NFTs) in the brain is a common risk factor in tauopathies including Alzheimer's disease (AD). Several strategies have been implemented to target NFTs, among which chaperones, which facilitate the proper folding of proteins, appear to hold great promise in effectively inhibiting TAU polymerization. The aim of this study was to analyze the impact of the chaperone Artemin on TAU aggregation in vitro. In this experimental study, recombinant TAU- or Artemin proteins were expressed in E.coli bacteria, and purified using ion-exchange and affinity chromatography. Sodium dodecyl sulfate-poly acrylamide gel electrophoresis (SDS-PAGE) was used to run the extracted proteins and check their purity. Heparin was used as an aggregation inducer. The interaction kinetics of TAU aggregation and disassembly was performed using thioflavin T (ThT) fluorescence analysis and circular dichroism (CD) spectroscopy. Ion-exchange and affinity chromatography yielded highly pure TAU and Artemin proteins for subsequent analyses. In addition, we found that heparin efficiently induced TAU fibrillization 48 hours post-incubation, as evidenced by ThT assay. Importantly, Artemin was observed to effectively block the aggregation of both physiologic- and supraphysiologic TAU concentrations in a dose-dependent manner, as judged by ThT and CD spectroscopy analyses. Our collective results show, for the first time, that the chaperone Artemin could significantly inhibit aggregation of the TAU proteins in a dose-dependent manner, and support Artemin as a potential potent blocker of TAU aggregation in people with AD.

[This corrects the article DOI: 10.1371/journal.pone.0268156.].

In this study, we have improved the power factor of conductive polymer nanocomposites by combining layer-by-layer assembly with electrochemical deposition to produce flexible thermoelectric materials based on PEDOT/carbon nanotubes (CNTs)—films. To produce films based on CNTs and PEDOT, a dual approach has been employed: (i) the layer-by-layer method has been utilized for constructing the CNTs layer and (ii) electrochemical polymerization has been used in the synthesis of the conducting polymer. Moreover, the thermoelectric properties were optimized by controlling the experimental conditions including the number of deposition cycles and electropolymerizing time. The electrical characterization of the samples was carried out by measuring the Seebeck voltage produced under a small temperature difference and by measuring the electrical conductivity using the four-point probe method. The resulting values of the Seebeck coefficient S and σ were used to determine the power factor. The structural and morphological analyses of CNTs/PEDOT samples were carried out using scanning electron microscopy (SEM) and Raman spectroscopy. The best power factor achieved was 131.1 (μWm−1K−2), a competitive value comparable to some inorganic thermoelectric materials. Since the synthesis of the CNT/PEDOT layers is rather simple and the ingredients used are relatively inexpensive and environmentally friendly, the proposed nanocomposites are a very interesting approach as an application for recycling heat waste.

The recent development in the field of wearable electronics has increased the demand for batteries as power sources which are subjected to periodic recharging and replacement. Therefore, the next challenge is to design new systems for sustainable energy to power portable electronic devices that can be easily integrated into textiles such as thermoelectric generators that can convert waste heat into electricity. Looking at this scenario, this work shows a methodology to prepare thermoelectric textiles by electrochemical polymerization of poly(3,4‐ethylenedioxythiophene) (PEDOT) on felt fabrics. The polymerization of PEDOT is carried out utilizing three different counterions, LiClO4, 1‐butyl‐3‐methylimidazolium hexafluorophosphate (PF6), and 1‐ethyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide (BTFMSI) to provide a complete understanding of the role of the counterion in the thermoelectric properties. The electrical conductivity and Seebeck coefficient are dependent on the counterion, reaching the maximum ZT for PEDOT polymerized in presence of BTFMSI due to an improvement of carrier mobility. In addition, the manufactured textile thermoelectric device showed an outstanding power output (6.5 µW) compared to the previous devices reported to date. This article shows a textile‐based wearable thermoelectric generator (T‐wTEG) manufactured with felt fabrics coated with MWCNT and poly(3,4‐ethylenedioxythiophene):1‐Ethyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide. These fabrics are cut into small pieces (5 × 10 mm) and connected ten pieces in parallel, obtaining a thermoelectric unit. Then fourteen units are connected in series, obtaining the final T‐wTEG. This T‐wTEG produces an output power of 6.5 µW with a thermal gradient of 57 K.

In the present study, organophosphorus hydrolase enzyme on Functionalized ferric magnetic nanoparticles was immobilized by the covalent binding method. The Optimized amount for parameters of mg EDAC/mg nanoparticles, enzyme units (U)/mg nanoparticles, reaction time, and pH were determined to be 6.125, 0.1341, 3 h and 6.15 respectively. The amount of immobilization yield according to the enzyme activity was obtained to be 70% and also the amount of immobilized enzyme on nanoparticles was 0.25 U/mg nanoparticles. Stability studies showed significant increase in immobilized enzyme stability at 4, 25 and 45°C. The stability of Immobilized enzyme showed a 6.3-fold increase in comparison to free enzyme at 4°C. The results demonstrated that the pH stability of the immobilized enzyme significantly increased in comparison with free enzyme. The immobilized enzyme was usable and recoverable for seven cycles. The results depicted that 80% of enzyme activity was retained after fifth cycle. FTIR test showed the covalent binding of enzyme to magnetic nanoparticles’ surface and the modified enzyme magnetic nanoparticles property was superparamagnetic by vibrating sample magnetometer test.

Human induced pluripotent stem cells (hiPSCs) are attractive sources of cells for disease modeling in vitro, and they may eventually provide access to cells/tissues for the treatment of many degenerative diseases. Stepwise differentiation from hiPSCs to definitive endoderm (DE) will identify a key step in hepatocytes and beta cell development and may prove useful for transplantation therapy for liver diseases and diabetes. Inducer of definitive endoderm 1 (IDE1) is known to play an important role in the regional specification of DE. Here, we have investigated the effect of stimulation with IDE1 on the development of hiPSCs into DE cells in three-dimensional (3D) cultures. The differentiation was determined by immunofluorescence staining with Sox17, FoxA2, and goosecoid (Gsc) and also by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) analysis. In this study, we showed that hiPSCs with 6-day IDE1 treatment (as chemical tool) on poly(ε-caprolactone) (PCL) nanofibrous scaffold were able to differentiate into DE cells.

Background: The widespread use of antibiotics is a cause of mutation in microorganisms and leads to the emergence of new micro organisms and resistance to common antibiotics. The purpose of this study is to investigate the synergistic effect of antibacterial synthetic essential oils of Artemisia quettensis and imipenem antibiotic on Pseudomonas aeruginosa isolated from clinical specimens and comparing it with conventional antibiotics. Methods: In this in vitro study, Artemisia quettensis.podlech oil was used alone and combined used with standard antibiotics to evaluate their antimicrobial activities. The disk diffusion method was employed. Results: The e sential oil of the plants with antibiotics led to a synergistic effect in some cases, because of injecting a quarter of antibiotics inhibit the growth of bacteria and prevents the creation of the colony. Conclusion: The combination of essential oils of the Artemisia quettensis with antibiotics may be useful in the fight against emerging microbial drug resistance.