ABSTRACT
The SARS-CoV-2 main protease (Mpro) is a major therapeutic target. The Mpro inhibitor, nirmatrelvir, is the antiviral component of Paxlovid, an orally available treatment for COVID-19. As Mpro inhibitor use increases, drug resistant mutations will likely emerge. We have established a non-pathogenic system, in which yeast growth serves as an approximation for Mpro activity, enabling rapid identification of mutants with altered enzymatic activity and drug sensitivity. The E166 residue is known to be a potential hot spot for drug resistance and yeast assays identified substitutions which conferred strong nirmatrelvir resistance and others that compromised activity. On the other hand, N142A and the P132H mutation, carried by the Omicron variant, caused little to no change in drug response and activity. Standard enzymatic assays confirmed the yeast results. In turn, we solved the structures of Mpro E166R, and Mpro E166N, providing insights into how arginine may drive drug resistance while asparagine leads to reduced activity. The work presented here will help characterize novel resistant variants of Mpro that may arise as Mpro antivirals become more widely used.
Subject(s)
COVID-19 , Coronavirus 3C Proteases , SARS-CoV-2 , Humans , Antiviral Agents/pharmacology , COVID-19/genetics , Mutation , Saccharomyces cerevisiae/genetics , SARS-CoV-2/geneticsABSTRACT
In 2014, 2016, and 2018, the United States experienced unprecedented spikes in pediatric cases of acute flaccid myelitis (AFM), which is a poliomyelitis-like paralytic illness. Accumulating clinical, immunological, and epidemiological evidence has identified enterovirus D68 (EV-D68) as a major causative agent of these biennial AFM outbreaks. There are currently no available FDA-approved antivirals that are effective against EV-D68, and the treatment for EV-D68-associated AFM is primarily supportive. Telaprevir is an food and drug administration (FDA)-approved protease inhibitor that irreversibly binds the EV-D68 2A protease and inhibits EV-D68 replication in vitro. Here, we utilize a murine model of EV-D68 associated AFM to show that early telaprevir treatment improves paralysis outcomes in Swiss Webster (SW) mice. Telaprevir reduces both viral titer and apoptotic activity in both muscles and spinal cords at early disease time points, which results in improved AFM outcomes in infected mice. Following intramuscular inoculation in mice, EV-D68 infection results in a stereotypic pattern of weakness that is reflected by the loss of the innervating motor neuron population, in sequential order, of the ipsilateral (injected) hindlimb, the contralateral hindlimb, and then the forelimbs. Telaprevir treatment preserved motor neuron populations and reduced weakness in limbs beyond the injected hindlimb. The effects of telaprevir were not seen when the treatment was delayed, and toxicity limited doses beyond 35 mg/kg. These studies are a proof of principle, provide the first evidence of benefit of an FDA-approved antiviral drug with which to treat AFM, and emphasize both the need to develop better tolerated therapies that remain efficacious when administered after viral infections and the development of clinical symptoms. IMPORTANCE Recent outbreaks of EV-D68 in 2014, 2016, and 2018 have resulted in over 600 cases of a paralytic illness that is known as AFM. AFM is a predominantly pediatric disease with no FDA-approved treatment, and many patients show minimal recovery from limb weakness. Telaprevir is an FDA-approved antiviral that has been shown to inhibit EV-D68 in vitro. Here, we demonstrate that a telaprevir treatment that is given concurrently with an EV-D68 infection improves AFM outcomes in mice by reducing apoptosis and viral titers at early time points. Telaprevir also protected motor neurons and improved paralysis outcomes in limbs beyond the site of viral inoculation. This study improves understanding of EV-D68 pathogenesis in the mouse model of AFM. This study serves as a proof of principle for the first FDA-approved drug that has been shown to improve AFM outcomes and have in vivo efficacy against EV-D68 as well as underlines the importance of the continued development of EV-D68 antivirals.
Subject(s)
Central Nervous System Viral Diseases , Enterovirus D, Human , Enterovirus Infections , Animals , United States , Mice , Enterovirus D, Human/physiology , Disease Models, Animal , Paralysis/drug therapy , Paralysis/etiology , Enterovirus Infections/pathology , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic useABSTRACT
SARS-CoV-2 is the etiological pathogen of the COVID-19 pandemic, which led to more than 6.5 million deaths since the beginning of the outbreak in December 2019. The unprecedented disruption of social life and public health caused by COVID-19 calls for fast-track development of diagnostic kits, vaccines, and antiviral drugs. Small molecule antivirals are essential complements of vaccines and can be used for the treatment of SARS-CoV-2 infections. Currently, there are three FDA-approved antiviral drugs, remdesivir, molnupiravir, and paxlovid. Given the moderate clinical efficacy of remdesivir and molnupiravir, the drug-drug interaction of paxlovid, and the emergence of SARS-CoV-2 variants with potential drug-resistant mutations, there is a pressing need for additional antivirals to combat current and future coronavirus outbreaks.In this Account, we describe our efforts in developing covalent and noncovalent main protease (Mpro) inhibitors and the identification of nirmatrelvir-resistant mutants. We initially discovered GC376, calpain inhibitors II and XII, and boceprevir as dual inhibitors of Mpro and host cathepsin L from a screening of a protease inhibitor library. Given the controversy of targeting cathepsin L, we subsequently shifted the focus to designing Mpro-specific inhibitors. Specifically, guided by the X-ray crystal structures of these initial hits, we designed noncovalent Mpro inhibitors such as Jun8-76-3R that are highly selective toward Mpro over host cathepsin L. Using the same scaffold, we also designed covalent Mpro inhibitors with novel cysteine reactive warheads containing di- and trihaloacetamides, which similarly had high target specificity. In parallel to our drug discovery efforts, we developed the cell-based FlipGFP Mpro assay to characterize the cellular target engagement of our rationally designed Mpro inhibitors. The FlipGFP assay was also applied to validate the structurally disparate Mpro inhibitors reported in the literature. Lastly, we introduce recent progress in identifying naturally occurring Mpro mutants that are resistant to nirmatrelvir from genome mining of the nsp5 sequences deposited in the GISAID database. Collectively, the covalent and noncovalent Mpro inhibitors and the nirmatrelvir-resistant hot spot residues from our studies provide insightful guidance for future work aimed at developing orally bioavailable Mpro inhibitors that do not have overlapping resistance profile with nirmatrelvir.
Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Cathepsin L , Pandemics , Antiviral Agents/pharmacology , Antiviral Agents/chemistry , Drug DesignABSTRACT
The implementation of a new intermediate-Hamiltonian Fock-space coupled-cluster (IHFSCC) scheme for the (3,0) sector of the Fock space is reported. In this IHFSCC approach, the three-body contributions in the cluster operator S(3,0) corresponding to the (3,0) sector of the Fock space are considered, while S(1,0) and S(2,0) at the (1,0) and (2,0) level only include one- and two-body operators. By introducing a suitable partition of the wave operator, the intermediate Hamiltonian, which only depends on the two-body operator of S(1,0), is obtained. S(2,0) and S(3,0) are not required within this new IHFSCC scheme, and a large reference space can be possibly employed. The performance of this (3,0) IHFSCC method in calculating triple ionization potentials and excitation energies for atoms and cations with a ground p3 configuration as well as adiabatic excitation energies for some molecules is investigated. The effect of the number of active virtual orbitals and three different types of orbitals, i.e., reference orbitals, restricted open-shell Hartree-Fock orbitals (ROHF) of the target systems, and canonicalized ROHF orbitals, on IHFSCC results, is also studied. Our calculations indicate that reasonable results can be achieved with this (3,0) IHFSCC method when a minimal reference space is employed. Further increasing the number of active orbitals does not necessarily improve the results. In addition, the IHFSCC results using canonicalized ROHF orbitals generally agree well with reference values, and they are not very sensitive to the number of active orbitals compared with results using the reference orbitals. The new (3,0) IHFSCC method can be applied to open-shell systems with three unpaired electrons with reasonable accuracy at a relatively low computational cost.
ABSTRACT
INTRODUCTION: Frailty has become a worldwide health burden that has a large influence on public health and clinical practice. The incidence of frailty is anticipated to increase as the ageing population increases. Myocardial injury after noncardiac surgery (MINS) is associated with short-term and long-term mortality. However, the incidence of MINS in frail geriatric patients is unknown. METHODS AND ANALYSIS: This prospective, multicentre, real-world observational cohort study will be conducted at 18 designated centres in China from January 2023 to December 2024, with an anticipated sample size of 856 patients aged 65 years and older who are scheduled to undergo noncardiac surgery. The primary outcome will be the incidence of MINS. MINS is defined as a fourth-generation plasma cardiac troponin T (cTnT) concentration ≥ 0.03 ng/mL exhibited at least once within 30 days after surgery, with or without symptoms of myocardial ischaemia. All data will be collected via electronic data acquisition. DISCUSSION: This study will explore the incidence of MINS in frail patients. The characteristics, predictive factors and 30-day outcomes of MINS in frail patients will be further investigated to lay the foundation for identifying clinical interventions. CLINICAL TRIAL REGISTRATION: https://beta. CLINICALTRIALS: gov/study/NCT05635877 , NCT05635877.
Subject(s)
Frailty , Myocardial Ischemia , Humans , Aged , Postoperative Complications/diagnosis , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Prospective Studies , Frailty/diagnosis , Frailty/epidemiology , Frailty/complications , Myocardial Ischemia/diagnosis , Myocardial Ischemia/epidemiology , Myocardial Ischemia/etiology , Cohort Studies , Risk Factors , Observational Studies as Topic , Multicenter Studies as TopicABSTRACT
Brilacidin, a mimetic of host defense peptides (HDPs), is currently in Phase 2 clinical trial as an antibiotic drug candidate. A recent study reported that brilacidin has antiviral activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by inactivating the virus. In this study, we discovered an additional mechanism of action of brilacidin by targeting heparan sulfate proteoglycans (HSPGs) on the host cell surface. Brilacidin, but not acetyl brilacidin, inhibits the entry of SARS-CoV-2 pseudovirus into multiple cell lines, and heparin, an HSPG mimetic, abolishes the inhibitory activity of brilacidin on SARS-CoV-2 pseudovirus cell entry. In addition, we found that brilacidin has broad-spectrum antiviral activity against multiple human coronaviruses (HCoVs) including HCoV-229E, HCoV-OC43, and HCoV-NL63. Mechanistic studies revealed that brilacidin has a dual antiviral mechanism of action including virucidal activity and binding to coronavirus attachment factor HSPGs on the host cell surface. Brilacidin partially loses its antiviral activity when heparin was included in the cell cultures, supporting the host-targeting mechanism. Drug combination therapy showed that brilacidin has a strong synergistic effect with remdesivir against HCoV-OC43 in cell culture. Taken together, this study provides appealing findings for the translational potential of brilacidin as a broad-spectrum antiviral for coronaviruses including SARS-CoV-2.
Subject(s)
COVID-19 Drug Treatment , Coronavirus 229E, Human , Coronavirus OC43, Human , Antiviral Agents/pharmacology , Guanidines , Humans , Pyrimidines , SARS-CoV-2ABSTRACT
The influenza A M2 wild-type (WT) proton channel is the target of the anti-influenza drug rimantadine. Rimantadine has two enantiomers, though most investigations into drug binding and inhibition have used a racemic mixture. Solid-state NMR experiments using the full length-M2 WT have shown significant spectral differences that were interpreted to indicate tighter binding for (R)- vs (S)-rimantadine. However, it was unclear if this correlates with a functional difference in drug binding and inhibition. Using X-ray crystallography, we have determined that both (R)- and (S)-rimantadine bind to the M2 WT pore with slight differences in the hydration of each enantiomer. However, this does not result in a difference in potency or binding kinetics, as shown by similar values for kon, koff, and Kd in electrophysiological assays and for EC50 values in cellular assays. We concluded that the slight differences in hydration for the (R)- and (S)-rimantadine enantiomers are not relevant to drug binding or channel inhibition. To further explore the effect of the hydration of the M2 pore on binding affinity, the water structure was evaluated by grand canonical ensemble molecular dynamics simulations as a function of the chemical potential of the water. Initially, the two layers of ordered water molecules between the bound drug and the channel's gating His37 residues mask the drug's chirality. As the chemical potential becomes more unfavorable, the drug translocates down to the lower water layer, and the interaction becomes more sensitive to chirality. These studies suggest the feasibility of displacing the upper water layer and specifically recognizing the lower water layers in novel drugs.
ABSTRACT
The main protease (Mpro) is a validated antiviral drug target of SARS-CoV-2. A number of Mpro inhibitors have now advanced to animal model study and human clinical trials. However, one issue yet to be addressed is the target selectivity over host proteases such as cathepsin L. In this study we describe the rational design of covalent SARS-CoV-2 Mpro inhibitors with novel cysteine reactive warheads including dichloroacetamide, dibromoacetamide, tribromoacetamide, 2-bromo-2,2-dichloroacetamide, and 2-chloro-2,2-dibromoacetamide. The promising lead candidates Jun9-62-2R (dichloroacetamide) and Jun9-88-6R (tribromoacetamide) had not only potent enzymatic inhibition and antiviral activity but also significantly improved target specificity over caplain and cathepsins. Compared to GC-376, these new compounds did not inhibit the host cysteine proteases including calpain I, cathepsin B, cathepsin K, cathepsin L, and caspase-3. To the best of our knowledge, they are among the most selective covalent Mpro inhibitors reported thus far. The cocrystal structures of SARS-CoV-2 Mpro with Jun9-62-2R and Jun9-57-3R reaffirmed our design hypothesis, showing that both compounds form a covalent adduct with the catalytic C145. Overall, these novel compounds represent valuable chemical probes for target validation and drug candidates for further development as SARS-CoV-2 antivirals.
Subject(s)
Acetamides/pharmacology , Antiviral Agents/pharmacology , Coronavirus 3C Proteases/antagonists & inhibitors , Protease Inhibitors/pharmacology , SARS-CoV-2/drug effects , Animals , Antiviral Agents/chemistry , Cathepsin L/antagonists & inhibitors , Drug Design , Drug Discovery , Enzyme Inhibitors/pharmacology , Humans , Models, Molecular , Molecular Dynamics Simulation , Structure-Activity Relationship , Substrate SpecificityABSTRACT
Pretreatment can improve the hydrolysis efficiency of cellulose, in which biological pretreatment plays an important role. In the present study, we uncovered that Rhodococcus has the ability of lignin degradation, which can decompose lignin and serve as a carbon source to meet the needs of its own growth. We used Rhodococcus to pretreat the corn stalks and evaluate the effect on cellulose hydrolysis. The concentration of reducing sugar produced by the hydrolysis of corn stalk after pretreatment of Rhodococcus is 2.95 g/L. SEM imaging showed that Rhodococcus pretreatment resulted the surface of corn stalk to be no longer complete, some lamellar structures fall off, and leave obvious traces, and obvious delamination was found at the edge of the fault. AFM imaging showed that the pretreatment changed the lignin structure of the corn stalk material surface, resulting in a higher surface roughness of 9.37. These results indicated that Rhodococcus pretreatment can improve the saccharification efficiency of cellulose by removing lignin and increasing the surface roughness of the material.
Subject(s)
Biotechnology/methods , Cellulose/chemistry , Rhodococcus/metabolism , Zea mays/metabolism , Biomass , Hydrolysis , Lignin/chemistry , Materials Testing , Microscopy, Atomic Force , Microscopy, Electron, Scanning , Peroxidases/chemistry , Surface PropertiesABSTRACT
Genes and environmental conditions are thought to interact in the development of postnatal brain in schizophrenia (SZ). Genome wide association studies have identified that PPARGC1A being one of the top candidate genes for SZ. We previously reported GABAergic neuron-specific PGC-1α knockout mice (Dlx5/6-Cre:PGC-1αfl/fl) presented some characteristic features of SZ. However, there is a fundamental gap of the molecular mechanism by which PGC-1α gene involved in the developmental trajectory to SZ. To explore whether PGC-1α regulates environmental factors interacting with genetic susceptibility to trigger symptom onset and disease progression, PGC-1α deficient mice were utilized to model genetic effect and an additional oxidative stress was induced by GBR injection. We confirm that PGC-1α gene deletion prolongs critical period (CP) timing, as revealed by delaying maturation of PV interneurons (PVIs), including their perineuronal nets (PNNs). Further, we confirm that gene × environment (G × E) influences CP plasticity synergistically and the interaction varies as a function of age, with the most sensitive period being at preweaning stage, and the least sensitive one at early adult age in PGC-1α deficient mice. Along this line, we find that the synergic action of G × E is available in ChABC-infusion PGC-1α KO mice, even though during the adulthood, and the neuroplasticity seems to remain open to fluctuate. Altogether, these results refine the observations made in the PGC-1α deficient mice, a potential mouse model of SZ, and illustrate how PGC-1α regulates CP plasticity via G × E interaction in the developmental trajectory to SZ.
Subject(s)
GABAergic Neurons/metabolism , Interneurons/metabolism , Parvalbumins/metabolism , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/metabolism , Schizophrenia/metabolism , Animals , Chondroitin ABC Lyase/pharmacology , Gene-Environment Interaction , Gyrus Cinguli/cytology , Gyrus Cinguli/diagnostic imaging , Humans , Immunohistochemistry , Mice , Mice, Knockout , Microscopy, Electron, Scanning , Mitochondria/metabolism , Mitochondria/pathology , Mitochondria/ultrastructure , Neuronal Plasticity/genetics , Neuronal Plasticity/physiology , Oxidative Stress/physiology , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/deficiency , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/genetics , Puberty/metabolism , Schizophrenia/diagnostic imaging , Schizophrenia/genetics , Schizophrenia/physiopathology , WeaningABSTRACT
Enterovirus D68 (EV-D68) is a viral pathogen that leads to severe respiratory illness and has been linked with the development of acute flaccid myelitis (AFM) in children. No vaccines or antivirals are currently available for EV-D68 infection, and treatment options for hospitalized patients are limited to supportive care. Here, we report the expression of the EV-D68 2A protease (2Apro) and characterization of its enzymatic activity. Furthermore, we discovered that telaprevir, an FDA-approved drug used for the treatment of hepatitis C virus (HCV) infections, is a potent antiviral against EV-D68 by targeting the 2Apro enzyme. Using a fluorescence resonance energy transfer-based substrate cleavage assay, we showed that the purified EV-D68 2Apro has proteolytic activity selective against a peptide sequence corresponding to the viral VP1-2A polyprotein junction. Telaprevir inhibits EV-D68 2Apro through a nearly irreversible, biphasic binding mechanism. In cell culture, telaprevir showed submicromolar-to-low-micromolar potency against several recently circulating neurotropic strains of EV-D68 in different human cell lines. To further confirm the antiviral drug target, serial viral passage experiments were performed to select for resistance against telaprevir. An N84T mutation near the active site of 2Apro was identified in resistant viruses, and this mutation reduced the potency of telaprevir in both the enzymatic and cellular antiviral assays. Collectively, we report for the first time the in vitro enzymatic activity of EV-D68 2Apro and the identification of telaprevir as a potent EV-D68 2Apro inhibitor. These findings implicate EV-D68 2Apro as an antiviral drug target and highlight the repurposing potential of telaprevir to treat EV-D68 infection.IMPORTANCE A 2014 EV-D68 outbreak in the United States has been linked to the development of acute flaccid myelitis in children. Unfortunately, no treatment options against EV-D68 are currently available, and the development of effective therapeutics is urgently needed. Here, we characterize and validate a new EV-D68 drug target, the 2Apro, and identify telaprevir-an FDA-approved drug used to treat hepatitis C virus (HCV) infections-as a potent antiviral with a novel mechanism of action toward 2Apro 2Apro functions as a viral protease that cleaves a peptide sequence corresponding to the VP1-2A polyprotein junction. The binding of telaprevir potently inhibits its enzymatic activity, and using drug resistance selection, we show that the potent antiviral activity of telaprevir was due to 2Apro inhibition. This is the first inhibitor to selectively target the 2Apro from EV-D68 and can be used as a starting point for the development of therapeutics with selective activity against EV-D68.
Subject(s)
Antiviral Agents/pharmacology , Enterovirus D, Human/drug effects , Enterovirus Infections/drug therapy , Oligopeptides/pharmacology , A549 Cells , Cell Line , HEK293 Cells , HeLa Cells , HumansABSTRACT
Non-polio enteroviruses such as enterovirus A71 (EV-A71), EV-D68, and coxsackievirus B3 (CVB3) are significant human pathogens with disease manifestations ranging from mild flu-like symptoms to more severe encephalitis, myocarditis, acute flaccid paralysis/myelitis, and even death. There is currently no effective antivirals to prevent or treat non-polio enterovirus infection. In this study, we report our progress in developing potent and broad-spectrum antivirals against these non-polio enteroviruses. Starting from our previously developed lead compounds that had potent antiviral activity against EV-D68, we synthesized 43 analogs and profiled their broad-spectrum antiviral activity against additional EV-D68, EV-A71, and CVB3 viruses. Promising candidates were also selected for mouse microsomal stability test to prioritize lead compounds for future in vivo mouse model studies. Collectively, this multi-parameter optimization process revealed a promising lead compound 6aw that showed single-digit to submicromolar EC50 values against two EV-D68 strains (US/KY and US/MO), two EV-A71 strains (Tainan and US/AK), and one CVB3 strain, with a high selectivity index. Encouragingly, 6aw was stable in mouse microsomes with a half-life of 114.7â¯min. Overall, 6aw represents one of the most potent broad-spectrum antiviral against non-polio enteroviruses, rendering it a promising lead candidate for non-polio enteroviruses with translational potential.
Subject(s)
Antiviral Agents/therapeutic use , Enterovirus/drug effects , Quinolines/therapeutic use , Animals , Antiviral Agents/pharmacology , Enterovirus/pathogenicity , Humans , Mice , Quinolines/pharmacologyABSTRACT
Significant evidence from various sources suggests that structural alterations in mitochondrial function may play a role in both the pathogenesis of mood disorders and the therapeutic effects of available treatments. PGC-1α is a distinct transcriptional regulator designed to mediate the synchronous release of neurotransmitter in the brain and thereby to coordinate a number of gene expression pathways to promote mitochondrial biogenesis and oxidative phosphorylation. The role of PGC-1α in the context of affective disorder phenotypes and treatments has been suggested but not studied in depth. To further investigate the possible involvement of PGC-1α in affective disorders, we generated conditional PGC-1α null mice through transgenic expression of cre recombinase under the control of a Dlx5/6 promoter; cre-mediated excision events were limited to γ-amino-butyric-acid (GABA)-ergic specific neurons. We tested these mice in a battery of behavioral tests related to affective change including spontaneous activity, elevated plus maze, forced swim test, and tail suspension test. Results demonstrated that mice lacking PGC-1α in GABAergic neurons exhibited increased activity across tests that might be related to a mania-like phenotype. These results suggest possible relevance of PGC-1α to affective change, which corresponds with data connecting mitochondrial function and affective disorders and their treatment.
Subject(s)
Bipolar Disorder/genetics , Hyperkinesis/genetics , Motor Activity/genetics , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/genetics , Animals , Bipolar Disorder/metabolism , Disease Models, Animal , GABAergic Neurons/metabolism , Gene Expression Regulation , Hyperkinesis/metabolism , Mice , Mice, Knockout , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/metabolism , Promoter Regions, GeneticABSTRACT
Influenza viruses are respiratory pathogens that are responsible for annual influenza epidemics and sporadic influenza pandemics. Oseltamivir (Tamiflu®) is currently the only FDA-approved oral drug that is available for the prevention and treatment of influenza virus infection. However, its narrow therapeutic window, coupled with the increasing incidence of drug resistance, calls for the next generation of influenza antivirals. In this study, we discovered hesperadin, an aurora B kinase inhibitor, as a broad-spectrum influenza antiviral through forward chemical genomics screening. Hesperadin inhibits multiple human clinical isolates of influenza A and B viruses with single to submicromolar efficacy, including oseltamivir-resistant strains. Mechanistic studies revealed that hesperadin inhibits the early stage of viral replication by delaying the nuclear entry of viral ribonucleoprotein complex, thereby inhibiting viral RNA transcription and translation as well as viral protein synthesis. Moreover, a combination of hesperadin with oseltamivir shows synergistic antiviral activity, therefore hesperadin can be used either alone to treat infections by oseltamivir-resistant influenza viruses or used in combination with oseltamivir to delay resistance evolution among oseltamivir-sensitive strains. In summary, the discovery of hesperadin as a broad-spectrum influenza antiviral offers an alternative to combat future influenza epidemics and pandemics.
Subject(s)
Antiviral Agents/pharmacology , Indoles/pharmacology , Influenza A virus/drug effects , Influenza B virus/drug effects , Protein Kinase Inhibitors/pharmacology , Sulfonamides/pharmacology , Animals , Antiviral Agents/chemistry , Aurora Kinase B/antagonists & inhibitors , Cells, Cultured , Dogs , Dose-Response Relationship, Drug , Drug Resistance, Viral , Drug Synergism , Gene Expression Regulation, Viral/drug effects , Humans , Indoles/chemistry , Madin Darby Canine Kidney Cells , Oseltamivir/pharmacology , Protein Kinase Inhibitors/chemistry , Sulfonamides/chemistry , Viral Plaque Assay , Virus Replication/drug effectsABSTRACT
Bacterial protein synthesis is the target for numerous natural and synthetic antibacterial agents. We have developed a poly(U) mRNA-directed aminoacylation/translation (A/T) protein synthesis system composed of phenylalanyl-tRNA synthetases (PheRS), ribosomes, and ribosomal factors from Pseudomonas aeruginosa This system has been used for high-throughput screening of a natural-compound library. Assays were developed for each component of the system to ascertain the specific target of inhibitory compounds. In high-throughput screens, 13 compounds were identified that inhibit protein synthesis with 50% inhibitory concentrations ranging from 0.3 to >80 µM. MICs were determined for the compounds against the growth of a panel of pathogenic organisms, including Enterococcus faecalis, Escherichia coli, Haemophilus influenzae, Moraxella catarrhalis, P. aeruginosa, Staphylococcus aureus, and Streptococcus pneumoniae Three of the compounds were observed to have broad-spectrum activity and inhibited a hypersensitive strain of P. aeruginosa with MICs of 8 to 16 µg/ml. The molecular target of each of the three compounds was determined to be PheRS. One compound was found to be bacteriostatic, and one compound was bactericidal against both Gram-positive and Gram-negative pathogens. The third compound was observed to be bacteriostatic against Gram-positive and bactericidal against Gram-negative bacteria. All three compounds were competitive with the substrate ATP; however, one compound was competitive, one was uncompetitive, and one noncompetitive with the amino acid substrate. Macromolecular synthesis assays confirm the compounds inhibit protein synthesis. The compounds were shown to be more than 25,000-fold less active than the control staurosporine in cytotoxicity MTT testing in human cell lines.
Subject(s)
Anti-Bacterial Agents/pharmacology , Biological Products/pharmacology , Protein Biosynthesis/drug effects , Pseudomonas aeruginosa/drug effects , Bacterial Proteins/metabolism , Cell Line , Gram-Positive Bacteria/drug effects , HEK293 Cells , Humans , Inhibitory Concentration 50 , Pseudomonas Infections/drug therapy , Pseudomonas aeruginosa/metabolism , Ribosomes/drug effectsABSTRACT
The paper summarizes the clinical experience of professor ZHANG Ren in the staging treatment with characteristic acupuncture techniques for oculomotor paralysis. According to the symptoms of oculomotor paralysis, the staging treatment is given, in which acupuncture is dominant and the needling techniques are optioned in compliance with the symptoms. In the early, middle and late stages of illness, three different acupuncture therapies are delivered accordingly, i.e. the combination of the point-toward-point needling at the four acupoints located on the forehead and the electroacupuncture with disperse-dense wave, the surrounding needling and the triple needling at the acupoints around the eyeball, as well as the perpendicular needle insertion at the three acupoints within the orbit. Professor ZHANG Ren lays the stress on identifying the etiology and differentiating the symptoms, as well as the early intervention for the disease. For the intractable cases, the comprehensive regimen such as acupoint injection, dermal needling and auricular point sticking is supplemented. During treatment, the spirit harmonization is greatly considered to ensure the effectiveness. On the basis of the staging acupuncture therapy, the acupuncture technique for harmonizing the spirit and regulating qi is combined to obtain the favorable clinical effect on oculomotor paralysis.
Subject(s)
Acupuncture Therapy , Acupuncture , Electroacupuncture , Ophthalmoplegia , Humans , Acupuncture Therapy/methods , Acupuncture PointsABSTRACT
To fulfill ultra-high-definition display, efficient and bright green organic light-emitting diodes with Commission Internationale de l'Éclairage y-coordinate ≥ 0.7 are required. Although there are some preceding reports of highly efficient devices based on pure-green multi-resonance emitters, the efficiency rolloff and device stabilities for those pure-green devices are still unsatisfactory. Herein, we report the rational design of two pure-green multi-resonance emitters for achieving highly stable and efficient pure-green devices with CIEx,ys that are close to the NTSC and BT. 2020 standards. In this study, our thermally activated delayed fluorescence OLEDs based on two pure-green multi-resonance emitters result in CIEy up to 0.74. In hyperfluorescent device architecture, the CIExs further meet the x-coordinate requirements, i.e., NTSC (0.21) and BT. 2020 (0.17), while keeping their CIEys ~ 0.7. Most importantly, hyperfluorescent devices display the high maximum external quantum efficiencies of over 25% and maximum luminance of over 105 cd m-2 with suppressed rolloffs (external quantum efficiency of ~20% at 104 cd m-2) and long device stabilities with LT95s of ~ 600 h.
ABSTRACT
BACKGROUND: The outbreak of coronavirus disease 2019 (COVID-19) infection posed a huge threat and burden to public healthcare in late 2022. Non-drug measures of traditional Chinese medicine (TCM), such as acupuncture, cupping and moxibustion, are commonly used as adjuncts in China to help in severe cases, but their effects remain unclear. OBJECTIVES: To observe the clinical effect of TCM non-drug measures in improving respiratory function and symptoms among patients with severe COVID-19. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS: This study was designed as a multicenter, assessor-blind, randomized controlled trial. Hospitalized patients with COVID-19 were randomly assigned to the treatment or control group. The treatment group received individualized TCM non-drug measures in combination with prone position ventilation, while the control group received prone position ventilation only for 5 consecutive days. MAIN OUTCOME MEASURES: The primary outcome measures were the percentage of patients with improved oxygen saturation (SpO2) at the end of the 5-day intervention, as well as changes of patients' respiratory rates. The secondary outcome measures included changes in SpO2 and total score on the self-made respiratory symptom scale. The improvement rate, defined as a 3-day consecutive increase in SpO2, the duration of prone positioning, and adverse events were recorded as well. RESULTS: Among the 198 patients included in the intention-to-treat analysis, 159 (80.3%) completed all assessments on day 5, and 39 (19.7%) patients withdrew from the study. At the end of the intervention, 71 (91%) patients in the treatment group had SpO2 above 93%, while 61 (75.3%) in the control group reached this level. The proportion of participant with improved SpO2 was significantly greater in the intervention group (mean difference [MD] = 15.7; 95% confidence interval [CI]: 4.4, 27.1; P = 0.008). Compared to the baseline, with daily treatment there were significant daily decreases in respiratory rates in both groups, but no statistical differences between groups were found (all P ≥ 0.05). Compared to the control group, the respiratory-related symptoms score was lower among patients in the treatment group (MD = -1.7; 95%CI: -2.8, -0.5; P = 0.008) after day 3 of treatment. A gradual decrease in the total scores of both groups was also observed. Thirty-one adverse events occurred during the intervention, and 2 patients were transferred to the intensive care unit due to deterioration of their illness. CONCLUSION: TCM non-drug measures combined with prone positioning can effectively treat patients with severe COVID-19. The combined therapy significantly increased SpO2 and improved symptom scores compared to prone positioning alone, thus improving the patients' respiratory function to help them recover. However, the improvement rate did not differ between the two groups. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR2300068319). Please cite this article as: Yin X, Jin Z, Li F, Huang L, Hu YM, Zhu BC, Wang ZQ, Li XY, Li JP, Lao LX, Mi YQ, Xu SF. Effectiveness and safety of adjunctive non-drug measures in improving respiratory symptoms among patients with severe COVID-19: A multicenter randomized controlled trial. J Integr Med. 2024; Epub ahead of print.
ABSTRACT
FlipGFP assay characterizes the intracellular drug target engagement to Mpro and PLpro and can be performed in the biosafety level 1/2 settings. Here, we provide the detailed protocol for the cell-based FlipGFP assay to identify and characterize SARS-CoV-2 Mpro and PLpro inhibitors. We describe steps for cell passage and seeding, transfection, addition of compounds, and their incubation and timing. We then detail the quantification of the fluorescence signal of the assay For complete details on the use and execution of this protocol, please refer to Ma et al.1.
ABSTRACT
An increasingly popular method for investigating visuospatial working memory assumes stored features of objects such as color and orientation vary along continua subject to internal noise. It adapts the stimulus adjustment procedure from perceptual psychophysics to assess the precision with which stored features are represented in memory. This contrasts with methods using discrete, categorical measures of feature retention. The current study examined the replicability of some phenomena documented using conventional methodology when assessed using a continuous measure of feature recall. These concern memory for a short series of objects and include effects of recency, prioritizing an individual object, and presenting an irrelevant additional object after the last item (a poststimulus 'suffix'). In two experiments we find broadly similar results using a continuous measure of color-orientation binding to those obtained previously using categorical measures, with small differences we regard as minor. We interpret the convergence between methods in terms of a simple analogy between categorical memory and categorical perception whereby categorical retrieval involves the application of a discrete criterion to an underlying continuum of stored feature information. We conclude by discussing some of the advantages and limitations of continuous and categorical measures of retention.