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Antiviral therapies are integral in the fight against SARS‐CoV‐2 (i.e. severe acute respiratory syndrome coronavirus 2), the causative agent of COVID‐19. Antiviral therapeutics can be divided into categories based on how they combat the virus, including viral entry into the host cell, viral replication, protein trafficking, post‐translational processing, and immune response regulation. Drugs that target how the virus enters the cell include: Evusheld, REGEN‐COV, bamlanivimab and etesevimab, bebtelovimab, sotrovimab, Arbidol, nitazoxanide, and chloroquine. Drugs that prevent the virus from replicating include: Paxlovid, remdesivir, molnupiravir, favipiravir, ribavirin, and Kaletra. Drugs that interfere with protein trafficking and post‐translational processing include nitazoxanide and ivermectin. Lastly, drugs that target immune response regulation include interferons and the use of anti‐inflammatory drugs such as dexamethasone. Antiviral therapies offer an alternative solution for those unable or unwilling to be vaccinated and are a vital weapon in the battle against the global pandemic. Learning more about these therapies helps raise awareness in the general population about the options available to them with respect to aiding in the reduction of the severity of COVID‐19 infection. In this 'A Guide To' article, we provide an in‐depth insight into the development of antiviral therapeutics against SARS‐CoV‐2 and their ability to help fight COVID‐19. [ABSTRACT FROM AUTHOR]

Bariatric surgery is currently the most effective strategy in treating severe obesity and its comorbidities, such as type 2 diabetes (T2D). However, the mechanism through which bariatric surgery mediates its benefits is not completely understood. Since obesity and T2D represent yet another inflammatory disease, and follicular helper T (Tfh) cells play important roles in inflammatory disorders, we investigated whether the Tfh activity was altered after Roux-en-Y gastric bypass ( RYGB), one of the most common bariatric surgery procedures. We found that the Tfh cells after RYGB were not significantly changed in number, but presented altered cytokine secretion profile, including lower interferon ( IFN)-γ, interleukin ( IL)-2, IL-4, and IL-17 secretion. Tfh cells after RYGB also downregulated inducible co-stimulator and programmed death-1. Interestingly, after Tfh cell-naive B cell coculture, Tfh cells after RYGB secreted more IL-10 than autologous Tfh cells before RYGB. The frequencies of IL-10-expressing and transforming growth factor ( TGF)-β-expressing regulatory B cells after Tfh cell-naive B cell coculture were directly correlated with the frequency of IL-10-expressing Tfh cells. Depletion of IL-10 in the coculture, however, resulted in fewer regulatory B cells. Finally, patients with greater increase in IL-10-expressing Tfh cells presented further reductions in body mass index, glycaemia, and body fat percentage. Together, these data demonstrated that the Tfh cells after RYGB presented lower inflammatory status and secreted higher IL-10, through which these Tfh cells promoted the development of regulatory B cells. Higher IL-10-expressing Tfh cell level also predicted better patient response to RYGB. [ABSTRACT FROM AUTHOR]

Background: Delta‐like homologue 1 (DLK1), a transmembrane protein, is highly expressed in hepatocellular carcinoma (HCC). We explored whether DLK1‐directed chimeric antigen receptor (CAR) T cells can specifically eliminate DLK1‐positive HCC cells and serve as a therapeutic strategy for HCC immunotherapy. Methods: We first characterized a homemade anti‐human DLK1 monoclonal antibody, sequenced the single‐chain Fragment variable (scFv) and integrated it into the second‐generation CAR lentiviral vector, and then developed the DLK1‐directed CAR‐T cells. The cytotoxic activities of DLK1‐directed CAR‐T cells against different HCC cells were evaluated in vitro and in vivo. Results: The genetically modified human T cells with the DLK1‐directed CARs produced cytotoxic activity against DLK1‐positive HCC cells. Additionally, the DLK1‐directed CARs enhanced T cell proliferation and activation in a DLK1‐dependent manner. Interestingly, the DLK1‐targeted CAR‐T cells significantly inhibited both subcutaneous and peritoneal xenograft tumours derived from human liver cancer cell lines HepG2 or Huh‐7. Conclusion: DLK1‐directed CAR‐T cells specifically suppresses DLK1‐positive HCC cells in vitro and in vivo. This study provides a novel transmembrane antigen DLK1 as a potential therapeutic target appropriate for CAR‐T cell therapy, which may be further developed as a clinical therapeutic strategy for HCC immunotherapy. [ABSTRACT FROM AUTHOR]

Summary: Callus formation is important for numerous biological processes in plants. Previously, we revealed that the PdeWRKY75–PdeRBOHB module positively regulates hydrogen peroxide (H2O2) accumulation, thereby affecting callus formation in poplar.In this study, we identified and confirmed a transcription factor, PdeERF114, that interacts with PdeWRKY75 both in vitro and in vivo. Gene expression analysis identified both PdeRBOHB and PdeEXPB2 as downstream genes of PdeERF114 and PdeWRKY75. Overexpression (OE) and reduced‐expression (RE) transgenic poplar lines for these four genes were generated, and the observation of callus formation was also performed in all plant materials.We demonstrated that PdeERF114 and PdeWRKY75 formed a protein complex and that this complex could bind W‐Box motifs in the promoters of PdeRBOHB and PdeEXPB2, thereby positively regulating the expression of PdeRBOHB and PdeEXPB2. The OE/RE transgenic lines for these four genes also showed enhanced/reduced callus formation.Overall, we revealed a novel gene regulatory network for the regulation of callus formation in plants that involves four genes and regulates callus formation through two pathways: the accumulation of H2O2 in explants and the relaxation of cell walls. In the future, the four genes could be used to enhance transformation effectiveness in genetic engineering. [ABSTRACT FROM AUTHOR]

Summary: Rice grain is a poor dietary source of zinc (Zn) but the primary source of cadmium (Cd) for humans; however, the molecular mechanisms for their accumulation in rice grain remain incompletely understood.This study functionally characterized a tonoplast‐localized transporter, OsMTP1. OsMTP1 was preferentially expressed in the roots, aleurone layer, and embryo of seeds. OsMTP1 knockout decreased Zn concentration in the root cell sap, roots, aleurone layer and embryo, and subsequently increased Zn concentration in shoots and polished rice (endosperm) without yield penalty. OsMTP1 haplotype analysis revealed elite alleles associated with increased Zn level in polished rice, mostly because of the decreased OsMTP1 transcripts.OsMTP1 expression in yeast enhanced Zn tolerance but did not affect that of Cd. While OsMTP1 knockout resulted in decreased uptake, translocation and accumulation of Cd in plant and rice grain, which could be attributed to the indirect effects of altered Zn accumulation.Our results suggest that rice OsMTP1 primarily functions as a tonoplast‐localized transporter for sequestrating Zn into vacuole. OsMTP1 knockout elevated Zn concentration but prevented Cd deposition in polished rice without yield penalty. Thus, OsMTP1 is a candidate gene for enhancing Zn level and reducing Cd level in rice grains. [ABSTRACT FROM AUTHOR]

Background: Magnetic nanoparticles (MNPs) are used as tracers without ionizing radiation in vascular imaging, molecular imaging, and neuroimaging. The relaxation mechanisms of magnetization in response to excitation magnetic fields are important features of MNPs. The basic relaxation mechanisms include internal rotation (Néel relaxation) and external physical rotation (Brownian relaxation). Accurate measurement of these relaxation times may provide high sensitivity for predicting MNP types and viscosity‐based hydrodynamic states. It is challenging to separately measure the Néel and Brownian relaxation components using sinusoidal excitation in conventional MPI. Purpose: We developed a multi‐exponential relaxation spectral analysis method to separately measure the Néel and Brownian relaxation times in the magnetization recovery process in pulsed vascular MPI. Methods: Synomag‐D samples with different viscosities were excited using pulsed excitation in a trapezoidal‐waveform relaxometer. The samples were excited at different field amplitudes ranging from 0.5 to 10 mT at intervals of 0.5 mT. The inverse Laplace transform‐based spectral analysis of the relaxation‐induced decay signal in the field‐flat phase was performed by using PDCO, a primal‐dual interior method for convex objectives. Néel and Brownian relaxation peaks were elucidated and measured on samples with various glycerol and gelatin concentrations. The sensitivity of viscosity prediction of the decoupled relaxation times was evaluated. A digital vascular phantom was designed to mimic a plaque with viscous MNPs and a catheter with immobilized MNPs. Spectral imaging of the digital vascular phantom was simulated by combining a field‐free point with homogeneous pulsed excitation. The relationship between the Brownian relaxation time from different tissues and the number of periods for signal averages was evaluated for a scan time estimation in the simulation. Results: The relaxation spectra of synomag‐D samples with different viscosity levels exhibited two relaxation time peaks. The Brownian relaxation time had a positive linear relationship with the viscosity in the range 0.9 to 3.2 mPa · s. When the viscosity was >3.2 mPa · s, the Brownian relaxation time saturated and did not change with increasing viscosity. The Néel relaxation time decreased slightly with an increase in the viscosity. The Néel relaxation time exhibited a similar saturation effect when the viscosity level was >3.2 mPa · s for all field amplitudes. The sensitivity of the Brownian relaxation time increased with the field amplitude and was maximized at approximately 4.5 mT. The plaque and catheter regions were differentiated from the vessel region in the simulated Brownian relaxation time map. The simulation results show that the Néel relaxation time was 8.33±0.09 μs in the plaque region, 8.30±0.08 μs in the catheter region, and 8.46±0.11 μs in the vessel region. The Brownian relaxation time was 36.60±2.31 μs in the plaque region, 30.17±1.24 μs in the catheter region, and 31.21±1.53 μs in the vessel region. If we used 20 excitation periods for image acquisition in the simulation, the total scan time of the digital phantom was approximately 100 s. Conclusion: Quantitative assessment of the Néel and Brownian relaxation times through inverse Laplace transform‐based spectral analysis in pulsed excitation, highlighting their potential for use in multi‐contrast vascular MPI. [ABSTRACT FROM AUTHOR]

SUMMARY: Phosphorus (P) is an important nutrient for plants. Here, we identify a WRKY transcription factor (TF) in poplar (Populus deltoides × Populus euramericana) (PdeWRKY65) that modulates tissue phosphate (Pi) concentrations in poplar. PdeWRKY65 overexpression (OE) transgenic lines showed reduced shoot Pi concentrations under both low and normal Pi availabilities, while PdeWRKY65 reduced expression (RE) lines showed the opposite phenotype. A gene encoding a Pi transporter (PHT), PdePHT1;9, was identified as the direct downstream target of PdeWRKY65 by RNA sequencing (RNA‐Seq). The negative regulation of PdePHT1;9 expression by PdeWRKY65 was confirmed by DNA–protein interaction assays, including yeast one‐hybrid (Y1H), electrophoretic mobility shift assay (EMSA), co‐expression of the promoters of PdePHT1;9 and PdeWRKY65 in tobacco (Nicotiana benthamiana) leaves, and chromatin immunoprecipitation–quantitative PCR. A second WRKY TF, PdeWRKY6, was subsequently identified and confirmed to positively regulate the expression of PdePHT1;9 by DNA–protein interaction assays. PdePHT1;9 and PdeWRKY6 OE and RE poplar transgenic lines were used to confirm their positive regulation of shoot Pi concentrations, under both normal and low Pi availabilities. No interaction between PdeWRKY6 and PdeWRKY65 was observed at the DNA or protein levels. Collectively, these data suggest that the low Pi‐responsive TFs PdeWRKY6 and PdeWRKY65 independently regulate the expression of PHT1;9 to modulate tissue Pi concentrations in poplar. Significance Statement: The genes PdeWRKY65 and PdeWRKY6, encoding WRKY transcription factors, and PdePHT1;9, encoding a phosphate (Pi) transporter, form a regulatory network to modulate tissue Pi concentrations in response to low Pi availability in poplar (Populus deltoides × Populus euramericana). In the regulatory network, PdeWRKY65 and PdeWRKY6 negatively and positively regulate the expression of PdePHT1;9 by binding to W‐Boxes within the PdePHT1;9 promoter, respectively. [ABSTRACT FROM AUTHOR]

Background: Trigeminal neuralgia (TN) is a neuropathic pain that occurs in branches of the trigeminal nerve. MicroRNAs (miRNAs) have been considered key mediators of neuropathic pain. This study was aimed to elucidate the pathophysiological function and mechanisms of miR‐223‐3p in mouse models of TN. Methods: Infraorbital nerve chronic constriction injury (CCI‐ION) was applied in male C57BL/6J mice to establish mouse models of TN. Pain responses were assessed utilizing Von Frey method. The expression of miR‐223‐3p, MKNK2, and MAPK/ERK pathway protein in trigeminal ganglions (TGs) of CCI‐ION mice was measured using RT‐qPCR and Western blotting. The concentrations of inflammatory cytokines were evaluated using Western blotting. The relationship between miR‐223‐3p and MKNK2 was tested by a luciferase reporter assay. Results: We found that miR‐223‐3p was downregulated, while MKNK2 was upregulated in TGs of CCI‐ION mice. MiR‐223‐3p overexpression by an intracerebroventricular injection of Lv‐miR‐223‐3p attenuated trigeminal neuropathic pain in CCI‐ION mice, as well as reduced the protein levels of pro‐inflammatory cytokines in TGs of CCI‐ION mice. MKNK2 was verified to be targeted by miR‐223‐3p. Additionally, miR‐223‐3p overexpression decreased the phosphorylation levels of ERK1/2, JNK, and p38 protein in TGs of CCI‐ION mice to inhibit MAPK/ERK signaling. Conclusions: Overall, miR‐223‐3p attenuates the development of TN by targeting MKNK2 to suppress MAPK/ERK signaling. [ABSTRACT FROM AUTHOR]

Negative symptoms in schizophrenia have been associated with functional changes in frontostriatal pathways. Dysregulation of the dopamine signal in frontostriatal pathways leads to the symptomology observed in schizophrenia. Although the catechol‐O‐methyltransferase (COMT) gene, one of the susceptibility genes for schizophrenia, has been associated with dopamine activities in prefrontal and striatal regions, it is still unclear whether the disease state and COMT val158met genotype have an interaction effect on the functional connectivity of frontostriatal pathways. In this study, we evaluated the possible interactions between COMT val158met variations and the disease state on the resting‐state functional connectivity (RSFC) of frontostriatal pathways in fifty‐one first episode schizophrenia (FES) patients (val/val: 29, met +: 22) with prominent negative symptoms and forty‐eight healthy controls (val/val: 31, met +: 17). Regions of interest were defined by the result of a meta‐analysis of frontostriatal pathways using the Neurosynth database. We found a significant genotype × disease interaction effect on the RSFC between the bilateral anterior cingulate (ACC) and right caudate, which overlapped with the main effect of the disease state. Behavioural regression analysis suggested that RSFC between the right ACC and right caudate correlated with the severity of SANS avolition–apathy scores in patients who were met carriers but not in patients who were val homozygous. Our findings suggest that the RSFC of frontostriatal pathways may differentially affected by an individual's COMT val158met genotype. [ABSTRACT FROM AUTHOR]

Physiological and emotional stressors are associated with or provoke each migraine attack and cause structural and functional changes in the central nervous system. The hippocampus, a limbic structure important in anxiety-related behavior, is vulnerable to long-term stress. Given that catechol- O-methyltransferase (COMT) is widely distributed in the hippocampus and its genetic variation is thought to contribute to the interindividual variability in pain perception and anxiety regulation, whether or not migraine and COMT val158met genotype have an interactive effect in the key brain area related to maladaptive stress, the hippocampus, is still poorly understood. Using T1-weighted and resting functional MRI, we evaluated the effect of COMT genetic variations on migraine and possible interactions between COMT and the disease in brain structure and function in 135 females with migraine without aura (MWoA) and 111 matched health controls (HC). Optimized voxel-based morphometry (VBM) and functional connectivity (FC) analyses were applied. From the whole brain VBM analysis, we found a significant disease × genotype interaction in the hippocampus, which overlapped with disease-related increase of gray matter (GM) in val homozygote migraineurs. In our results, increased GM in the hippocampus was only found in val homozygote MWoA compared to val homozygote HC. Moreover, FC between the hippocampus and the medial prefrontal cortex was significantly decreased in val homozygotes, and it was negatively correlated with self-rating anxiety scale values.Our results indicated that brain structure and function of the hippocampus are differentially affected by migraine in val homozygotes compared with met carriers. Hum Brain Mapp 36:1782-1795, 2015. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]