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This study investigates damage characteristics, dynamic structural performance changes, and quantitative damage assessment of high-pile wharf framed bents exposed to horizontal impact loads. Through extensive testing of wharf framed bents under such loads, a damage identification approach based on stiffness, natural vibration period, and acceleration data derived from experiments is presented. The findings reveal that under horizontal impact loads, framed bents initially exhibit tensile damage and leaning piles, followed by short straight piles. Additionally, structural damage results in a reduced self-oscillation frequency and an increased amplitude decay rate. Both stiffness-based and cycle-based damage indicators effectively track the cumulative damage progression of the structure. However, the cycle-based damage indicators demonstrate superior stability and accuracy, while acceleration-based indicators precisely identify the moment of damage mutation. This research contributes to enhancing local components, implementing damage identification methods, and advancing health monitoring practices in high-pile wharf projects, aligning with the standards of scientific publications in the field.
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Recombinant protein expression and purification are crucial in modern life sciences research. A fluorescent immunosensor termed Quenchbody (Q-body) was developed for real-time monitoring of FLAG-fused protein expression. Detection results showed that the limit of detection of the 3 × FLAG peptide detected by the TAMRA-labeled anti-FLAG Q-body was as low as 3.1 nM, with a half-maximal effective concentration of 21.4 nM. Furthermore, the anti-FLAG Q-body was used for detecting different proteins fused with a FLAG-tag at the N- or C-terminal. Subsequently, the constructed Q-body was used to monitor the real-time fermentation process of single-strand DNA-binding protein in Escherichia coli. Unlike previously reported Q-bodies that widely used Fab or scFv, the present study used a full-length anti-FLAG IgG for the first time. Owing to its excellent detection speed and sensitivity, the FLAG Q-body immunosensor has the potential to quantify and monitor target recombinant proteins in multiple biological processes in real-time.
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Técnicas Biossensoriais , Técnicas Biossensoriais/métodos , Imunoensaio , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes de FusãoRESUMO
Given the significant clinical potential of human plasminogen Kringle 5 on tumours, it is crucial to seek its receptors for a thorough comprehension of its physiological functions and mechanism. Eleven candidates have been screened out in our previous works. In the present work, we further inquired whether the candidate, von Willebrand factor type A domain 1 in coagulation factor C homology protein (abbr. vWA1), was a potential receptor of Kringle 5, and investigated their binding mechanism by bio-specific experiments, frontal affinity analysis (FA), and molecular dynamic simulation (MDS). After the potential was validated by bio-specific experiments, the FA results stated that vWA1 exhibited a strong interaction towards Kringle 5 in the proportion of 1:1 with the binding constant of 4.18 × 104 L/mol. The MDS results showed that the binding was mainly driven by electrostatic and Van der Waals forces and occurred spontaneously, during which vWA1 and Kringle 5 mutually fit each other by conformational changing into more flexible and suitable structures including fluctuations for five loops and partial transformation into a random coil for α6-helix in vWA1. Moreover, lysine binding site Leu71-Tyr74 was speculated responsible for Kringle 5 in binding and Tyr72 to be the key amino acid residue. In short, this work not only confirmed vWA1 as a potential Kringle 5 receptor but also provided valuable information on the detailed binding, facilitating the application development of Kringle 5 in regulating immune or inhibiting tumour migration through vWA1.
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Proteínas da Matriz Extracelular , Simulação de Dinâmica Molecular , Sequência de Aminoácidos , Sítios de Ligação , Humanos , Ligantes , Espectroscopia de Ressonância Magnética , Fragmentos de Peptídeos , Plasminogênio , Ligação Proteica , Conformação ProteicaRESUMO
OBJECTIVE: To screen activators of 2,3-diphosphoglycerate (BPG) mutase (BPGM) from Chinese herb medicines, so as to improve the hypoxia tolerance of erythrocytes. METHODS: BPGM was used as the receptor and Chinese medicine ingredients database was used as the ligand in the study. After Lipinski rule of five screening, LibDock and CDOCKER docking were used for virtual screening. The effect of the screened compounds on the affinity of BPGM in erythrocytes was verified. Finally, the erythrocytes were incubated in vitro to establish the erythrocyte hypoxia model, and the effect of the compound on the activity of BPGM in the erythrocyte hypoxia model was verified. RESULTS: Ten compounds with highest binding affinity to BPGM were selected by LibDock and CDOCKER, and the cytoplasm protein was incubated with the ten compounds. Compared with blank control group, methyl rosmarinate group, dihydrocurcumin high dose group, octahydrocurcumin medium dose group and coniferyl ferulate high dose group were able to further activate the BPGM, significantly increase the levels of 2, 3-BPG in normal erythrocytes (all P<0.05); while the low dose of tetrahydrocurcumin, high dose and low dose of aurantiamide, hexahydrocurcumin and medium dose of N- (p-coumaroyl) serotonin had a tendency to increase the contents of 2,3-BPG in normal erythrocytes (all P>0.05). In the hypoxic red blood cells, the medium dose methyl rosmarinate, medium dose octahydrocurcumin, high dose hexahydrocurcumin and medium dose N-(p-coumaroyl) serotonin could significantly increase the contents of 2,3-BPG (all P<0.05). CONCLUSION: The methyl rosmarinate, octahydrocurcumin, hexahydrocurcumin and N-(p-coumaroyl) serotonin could activate BPGM and increase the contents of 2,3-BPG in hypoxic erythrocytes.
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Bisfosfoglicerato Mutase , Medicina Tradicional Chinesa , Humanos , Bisfosfoglicerato Mutase/metabolismo , Serotonina , HipóxiaRESUMO
To investigate the active compounds from on the heart and brain of mice at simulated high altitude.Fifty healthy male adult BALB/c mice were randomly divided into normal control group, hypoxic model group, acetazolamide group, petroleum ether extract of (PESI) group and octacosan group with 10 mice in each group. Acetazolamide group, PESI group and octacosan group were treated with acetazolamide PESI (200â mg/kg) or octacosan by single tail vein injection, respectively. Except normal control group, the mice were exposed to a simulated high altitude of for in an animal decompression chamber. After the mice were sacrificed by cervical dislocation, the heart and brain were histologically observed by HE staining; superoxide dismutase (SOD) activity, total anti-oxidant capacity (T-AOC) and the content of malondialdehyde (MDA) in plasma, heart and brain tissues were detected by WST-1 method, ABTS method and TBA method, respectively; lactic acid and lactate dehydrogenase (LDH) activity in plasma, heart and brain tissues were detected by colorimetric method and microwell plate method, respectively; ATP content and ATPase activity in heart and brain tissues were detected by colorimetric method. PESI and octacosane significantly attenuated the pathological damages of heart and brain tissue at simulated high altitude; increased SOD activity, T-AOC and LDH activity, and decreased the contents of MDA and lactic acid in plasma, heart and brain tissues; increased the content of ATP in heart and brain tissues; increased the activities of Na-K ATPase, Mg ATPase, Ca ATPase and Ca-Mg ATPase in myocardial tissue; and increased the activities of Mg ATPase, Ca-Mg ATPase in brain tissue. PESI and octacosan exert anti-hypoxic activity by improving the antioxidant capacity, reducing the free radical levels, promoting the anaerobic fermentation, and alleviating the energy deficiency and metabolic disorders caused by hypoxia in mice.
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Altitude , Superóxido Dismutase , Animais , Encéfalo/metabolismo , Coração , Masculino , Malondialdeído , Camundongos , Camundongos Endogâmicos BALB C , Superóxido Dismutase/metabolismoRESUMO
Modern lifestyle factors (high-caloric food rich in fat) and daily chronic stress are important risk factors for metabolic disturbances. Increased hypothalamic-pituitary-adrenal (HPA) axis activity and the subsequent excess production of glucocorticoids (GCs) in response to chronic stress (CS) leads to increases in metabolic complications, such as type 2 diabetes and insulin resistance (IR). Melatonin (MLT), which protects several regulatory components of the HPA axis from GC-induced deterioration, might improve glucose homeostasis. Piromelatine is a melatonin receptor-1/melatonin receptor-2 (MT1/MT2) agonist with high affinity for MLT receptors and a longer duration of action than MLT. The objective of the present study was to explore the potential effects of piromelatine on glucose and lipid metabolism and insulin sensitivity in rats with IR induced by a high-fat diet combined with CS (CF). The results showed that piromelatine prevented the suppression of body weight gain and energy intake induced by CF and normalized CF-induced hyperglycemia and homeostasis model assessment-IR index, which suggests that piromelatine prevented whole-body IR. Piromelatine also prevented CF-induced dysregulation of genes involved in glucose and lipid metabolism, including proinflammatory cytokines, in adipose tissue. In addition, piromelatine also attenuated CF-induced excess free corticosterone release, increased glucocorticoid receptor expression, and decreased 11ß-hydroxysteroid dehydrogenase-1 expression, suggesting that piromelatine might ameliorate impaired glucose metabolism and prevent IR by normalizing HPA-axis functions. In conclusion, piromelatine might be a novel therapeutic agent for glucose intolerance and IR.
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Glicemia/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Glucose/antagonistas & inibidores , Indóis/uso terapêutico , Piranos/uso terapêutico , Receptores de Melatonina/agonistas , Estresse Psicológico/tratamento farmacológico , Animais , Glicemia/metabolismo , Doença Crônica , Glucose/metabolismo , Indóis/farmacologia , Masculino , Piranos/farmacologia , Ratos , Ratos Wistar , Receptores de Melatonina/metabolismo , Estresse Psicológico/metabolismoRESUMO
OBJECTIVE: To study the effects and potential mechanism of Kaixin-San and Danggui-Shaoyao-San on glucose and lipid metabolism in chronic stress rats fed with high-fat diet. METHODS: 50 male Wistar rats were randomly divided into normal control group (distilled water), high-fat diet with chronic stress group (distilled water), melatonin group(20 mg/kg), Kaixin-San group (445 mg/kg) and Danggui-Shaoyao-San group (3360 mg/kg). All drugs were orally administered. In addition to the normal control group, each group of rats were fed with high-fat, diet. Simultaneously, stress were carried out after drugs administration 1 h daily. The duration was lasted for six weeks. The rat body weight daily was recorded, and the 24 h period urine was collected to detect the level of urine corticosterone (CORT) after three weeks. The level of plasma intraperitoneal glucose tolerance (IVGTT) was detected after six weeks. Finally, rats were executed, and serum fasting blood glucose (FBG), triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), insulin (INS), adrenocorticotropic hormone releasing hormone (CRH), adrenocorticotropic hormone (ACTH), CORT and melatonin ( MLT) were determined. The weight of adrenal gland, liver glycogen and muscle glycogen levels were detected. The adrenal gland index, Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) and insulin sensitivity index( ISI) were calculated. RESULTS: Compared with normal group, model rats body weight, IVGTT (120 min), plasm CORT were decreased significantly. Serum TG, TC, LDL-C and urine CORT after three weeks were increased significantly. Kaixin-San and Danggui- Shaoyao-San could regulate the above indexes. CONCLUSION: Kaixin-San and Danggui-Shaoyao-San may regulate the activity of HPA axis, and improve glucose and lipid metabolism disorder in model rats by increasing melatonin secretion.
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Medicamentos de Ervas Chinesas/farmacologia , Glucose/metabolismo , Sistema Hipotálamo-Hipofisário , Metabolismo dos Lipídeos , Sistema Hipófise-Suprarrenal , Animais , Dieta Hiperlipídica , Masculino , Melatonina/metabolismo , Ratos , Ratos Wistar , Estresse FisiológicoRESUMO
Respiratory disease caused by coronavirus infection remains a global health crisis. Although several SARS-CoV-2-specific vaccines and direct-acting antivirals are available, their efficacy on emerging coronaviruses in the future, including SARS-CoV-2 variants, might be compromised. Host-targeting antivirals provide preventive and therapeutic strategies to overcome resistance and manage future outbreak of emerging coronaviruses. Cathepsin L (CTSL) and calpain-1 (CAPN1) are host cysteine proteases which play crucial roles in coronaviral entrance into cells and infection-related immune response. Here, two peptidomimetic α-ketoamide compounds, 14a and 14b, were identified as potent dual target inhibitors against CTSL and CAPN1. The X-ray crystal structures of human CTSL and CAPN1 in complex with 14a and 14b revealed the covalent binding of α-ketoamide groups of 14a and 14b to C25 of CTSL and C115 of CAPN1. Both showed potent and broad-spectrum anticoronaviral activities in vitro, and it is worth noting that they exhibited low nanomolar potency against SARS-CoV-2 and its variants of concern (VOCs) with EC50 values ranging from 0.80 to 161.7 nM in various cells. Preliminary mechanistic exploration indicated that they exhibited anticoronaviral activity through blocking viral entrance. Moreover, 14a and 14b exhibited good oral pharmacokinetic properties in mice, rats and dogs, and favorable safety in mice. In addition, both 14a and 14b treatments demonstrated potent antiviral potency against SARS-CoV-2 XBB 1.16 variant infection in a K18-hACE2 transgenic mouse model. And 14b also showed effective antiviral activity against HCoV-OC43 infection in a mouse model with a final survival rate of 60%. Further evaluation showed that 14a and 14b exhibited excellent anti-inflammatory effects in Raw 264.7 mouse macrophages and in mice with acute pneumonia. Taken together, these results suggested that 14a and 14b are promising drug candidates, providing novel insight into developing pan-coronavirus inhibitors with antiviral and anti-inflammatory properties.
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COVID-19 , Hepatite C Crônica , Humanos , Animais , Camundongos , Ratos , Cães , Calpaína , Catepsina L , Antivirais/farmacologia , Vacinas contra COVID-19 , Modelos Animais de Doenças , Camundongos Transgênicos , Anti-InflamatóriosRESUMO
Digoxin is a cardiac glycosylated steroid-like drug with a positive inotropic effect and has been widely used in treating congestive heart failure, atrial fibrillation, atrial flutter, and other heart diseases. Digoxin is also a dangerous drug, which can cause drug poisoning at a low blood drug concentration (2.73-3.9 nmol/L, i.e., 2.14-3.05 ng/mL). Therefore, the timely detection of a patient's blood drug concentration plays a significant role in controlling blood drug concentration, reducing the occurrence of drug poisoning events, and maximizing the role of drug therapy. In this study, a DNA vector for the expression of the antidigoxin antibody Fab fragment was constructed. With the vector, Fab was expressed in E. coli and purified, and 1.2 mg of antibodies was obtained from 100 mL of culture. An immunofluorescent sensor based on the mechanism of photoinduced electron transfer was constructed by labeling additional cysteines in the heavy chain variable region and light chain variable region of the antibody Fab fragment with fluorescent dyes. The assay for digoxin with the immunosensor could be finished within 5 min with a limit of detection of 0.023 ng/mL, a detectable range of 0.023 ng/mL to 100 µg/mL, and an EC50 of 0.256 ng/mL. A new approach for the rapid detection of digoxin was developed and will contribulte to therapeutic drug monitoring.
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The fate and transformation of PHCZs in the coastal river environment are not yet comprehensively understood. Paired river water and surface sediment were collected, and 12 PHCZs were analyzed to find out their potential sources and investigate the distribution of PHCZs between river water and sediment. The concentration of ∑PHCZs varied from 8.66 to 42.97 ng/g (mean 22.46 ng/g) in sediment and 17.91 to 81.82 ng/L (mean 39.07 ng/L) in river water. 18-B-36-CCZ was the dominant PHCZ congener in sediment, while 36-CCZ was in water. Meanwhile, the logKoc values for CZ and PHCZs were among the first calculated in the estuary and the mean logKoc varied from 4.12 for 1-B-36-CCZ to 5.63 for 3-CCZ. The logKoc values of CCZs were higher than those of BCZs, this may suggest that sediments have a higher capacity for accumulation and storage of CCZs than highly mobile environmental media.
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Poluentes Químicos da Água , Água , Rios , Carbazóis/análise , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental , Sedimentos GeológicosRESUMO
The 3C-like protease (3CLpro) is essential for the replication and transcription of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), making it a promising target for the treatment of corona virus disease 2019 (COVID-19). In this study, a series of 2,3,5-substituted [1,2,4]-thiadiazole analogs were discovered to be able to inhibit 3CLpro as non-peptidomimetic covalent binders at submicromolar levels, with IC50 values ranging from 0.118 to 0.582 µM. Interestingly, these compounds were also shown to inhibit PLpro with the same level of IC50 values, but had negligible effect on proteases such as chymotrypsin, cathepsin B, and cathepsin L. Subsequently, the antiviral abilities of these compounds were evaluated in cell-based assays, and compound 6g showed potent antiviral activity with an EC50 value of 7.249 µM. It was proposed that these compounds covalently bind to the catalytic cysteine 145 via a ring-opening metathesis reaction mechanism. To understand this covalent-binding reaction, we chose compound 6a, one of the identified hit compounds, as a representative to investigate the reaction mechanism in detail by combing several computational predictions and experimental validation. The process of ring-opening metathesis was theoretically studied using quantum chemistry calculations according to the transition state theory. Our study revealed that the 2,3,5-substituted [1,2,4]-thiadiazole group could covalently modify the catalytic cysteine in the binding pocket of 3CLpro as a potential warhead. Moreover, 6a was a known GPCR modulator, and our study is also a successful computational method-based drug-repurposing study.
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COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Peptídeo Hidrolases , Cisteína , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Cisteína Endopeptidases/metabolismo , Antivirais/químicaRESUMO
Macrocycles often exhibit good biological properties and potential druggability, which lead to versatile applications in the pharmaceutical industry. Herein, we report a highly efficient and practical methodology for the functionalization and macrocyclization of Trp and Trp-containing peptides via Pd(II)-catalyzed C-H alkenylation at the Trp C4 position. This method provides direct access to C4 maleimide-decorated Trp-containing peptidomimetics and maleimide-braced 17- to 30-membered peptide macrocycles. In particular, these unique macrocycles revealed low micro- to sub-micromolar EC50 values with promising anti-SARS-CoV-2 activities. Further explorations with computational methodologies and experimental validations indicated that these macrocycles exert antiviral effects through binding with the N protein of SARS-CoV-2.
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COVID-19 , Humanos , SARS-CoV-2 , Peptídeos/farmacologia , Peptídeos/química , Ciclização , MaleimidasRESUMO
Stems are more important to forage quality than leaves in alfalfa. To understand lignin formation at different stages in alfalfa, lignin distribution, anatomical characteristics and transcriptome profile were employed using two alfalfa cultivars. The results showed that the in vitro true digestibility (IVTD) of stems in WL168 was significantly higher than that of Zhungeer, along with the significantly lower neutral detergent fiber (NDF), acid detergent fiber (ADF) and lignin contents. In addition, Zhungeer exhibited increased staining of the xylem areas in the stems of different developmental stages compared to WL168. Interestingly, the stems of WL168 appeared intracellular space from the stage 3, while Zhungeer did not. The comparative transcriptome analysis showed that a total of 1993 genes were differentially expressed in the stem between the cultivars, with a higher number of expressed genes in the stage 4. Of the differentially expressed genes, starch and sucrose metabolism as well as phenylpropanoid biosynthesis pathways were the most significantly enriched pathways. Furthermore, expression of genes involved in lignin biosynthesis such as PAL, 4CL, HCT, CAD, COMT and POD coincides with the anatomic characteristics and lignin accumulation. These results may help elucidate the regulatory mechanisms of lignin biosynthesis and improve forage quality in alfalfa.
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The occurrence of gene duplication/amplification (GDA) provide potential material for adaptive evolution with environmental stress. Several molecular models have been proposed to explain GDA, recombination via short stretches of sequence similarity plays a crucial role. By screening genomes for such events, we propose a "SRS (short repeated sequence) *N + unit + SRS*N" amplified unit under USCE (unequal sister-chromatid exchange) for tandem amplification mediated by SRS with different repeat numbers in eukaryotes. The amplified units identified from 2131 well-organized amplification events that generate multi gene/element copy amplified with subsequent adaptive evolution in the respective species. Genomic data we analyzed showed dynamic changes among related species or subspecies or plants from different ecotypes/strains. This study clarifies the characteristics of variable copy number SRS on both sides of amplified unit under USCE mechanism, to explain well-organized gene tandem amplification under environmental stress mediated by SRS in all eukaryotes.
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Eucariotos/genética , Amplificação de Genes , Modelos Moleculares , Sequências Repetitivas de Ácido Nucleico , Adaptação Biológica/genética , Evolução Biológica , Meio AmbienteRESUMO
OBJECTIVE: To study the protective effects of the cream of the total flavonoids from Oxytropis falcata on the destructed skin of mice induced by moderate-wave ultraviolet (UVB) irradiation. METHODS: Dorsal skin of Wistar mice were treated with the cream of the total flavonoids from Oxytropis falcata and then irradiated with UVB in the dosage of 5 min once a day for one week. The tissue of skin was pathological diagnosed and the activities or contents of superoxide dismutase (SOD), malondialdehyde (MDA), hydroxyproline (Hyp), glutathione peroxidease (GSH-Px), glutathione (GSH), glutathion-s-transferase (GST), catalase (CAT) and hydroxy radical (*OH) were determined with chromatometry. RESULTS: The ultraviolet protective effects of the cream could be observed with appearance and pathology examine. The cream could increase the activities of SOD (P < 0.001), GSH-Px (P < 0.001), GST (P < 0.05) and CAT (P < 0.01), raise the content of Hyp (P < 0.001) significantly. The cream could also decrease the contents of MDA and *OH (P < 0.001), and the activities of GSH significantly (P < 0.001). CONCLUSION: The cream of the total flavonoids from Oxytropis falcata has protective effect on the destructed skin of mice induced by moderate-wave ultraviolet (UVB) irradiation.
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Antioxidantes/farmacologia , Flavonoides/farmacologia , Protetores contra Radiação/farmacologia , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Animais , Antioxidantes/administração & dosagem , Peso Corporal/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Estresse Oxidativo , Oxytropis/química , Distribuição Aleatória , Ratos , Ratos Wistar , Pele/metabolismo , Pele/patologia , Superóxido Dismutase/metabolismoRESUMO
Arenaviruses are a large family of enveloped negative-strand RNA viruses that include several causative agents of severe hemorrhagic fevers. Currently, there are no FDA-licensed drugs to treat arenavirus infection except for the off-labeled use of ribavirin. Here, we performed antiviral drug screening against the Old World arenavirus lymphocytic choriomeningitis virus (LCMV) using an FDA-approved drug library. Five drug candidates were identified, including mycophenolic acid, benidipine hydrochloride, clofazimine, dabrafenib, and apatinib, for having strong anti-LCMV effects. Further analysis indicated that benidipine hydrochloride inhibited LCMV membrane fusion, and an adaptive mutation on the LCMV glycoprotein D414 site was found to antagonize the anti-LCMV activity of benidipine hydrochloride. Mycophenolic acid inhibited LCMV replication by depleting GTP production. We also found mycophenolic acid, clofazimine, dabrafenib, and apatinib can inhibit the newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Owing to their FDA-approved status, these drug candidates can potentially be used rapidly in the clinical treatment of arenavirus and SARS-CoV-2 infection.
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COVID-19 , Preparações Farmacêuticas , Ensaios de Triagem em Larga Escala , Humanos , SARS-CoV-2 , Replicação ViralRESUMO
In this review, the literature data on the phytochemical and biological investigations on the genus of Meconopsis are summarized from 49 references. Up to now, more than 95 compounds were isolated from 19 Meconopsis plant species. The chemical constituents are mostly alkaloids, flavonoids, phenols, steroids, and terpenes, together with minor constituents of essential oil, and others. The crude extracts and metabolites have been found to possess various bioactivities including antitumor activity, central action, cardiovascular system effects, antibiosis, antiviral activity, anti-inflammatory effects, and other biological activities.
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Papaveraceae/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Sistema Cardiovascular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Estrutura MolecularRESUMO
Human plasminogen Kringle 5 is known to pose a more potent anti-angiogenesis effect by inducing endothelial cell apoptosis. Our previous studies have identified the peptide IGNSNTL as a binding sequence of Kringle 5 using Ph.D.-7 phage display peptide library and enzyme-linked immunosorbent assay. Here, eleven proteins were screened and summarized by BLAST, laminin α3 chain G1 domain (LG1) was considered as the most potential receptor based on E value and domain function. The specific interaction of them was directly revealed through ligand blot and a strong concentration-dependent manner occurred between them (Ka 4.30 × 105 L mol-1) in frontal chromatography observation. Moreover, R10A/P83R substitution Kringle 5 decreased the affinity capacity to LG1. Furthermore, a remarkable conformational change from random coil3 to α helix and α1 helix to random coil were observed to the structural compactness and stability for LG1. Surface loops and coils also showed fluctuations up to some extent, giving the binding surface greater flexibility and correspondingly allowing for induced-fit binding, which was -23.87 kcal mol-1 of the free energy with electrostatic force as a main driver. Taken together, not only effective theoretical prediction and experiment validated that LG1 is receptor of Kringle 5, but also give an new perspective of the binding mechanism of Kringle 5 and its specific receptor and could facilitate the development of novel agent targeted toward pathologic angiogenesis.
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Células Endoteliais/metabolismo , Laminina/química , Simulação de Dinâmica Molecular , Fragmentos de Peptídeos/metabolismo , Plasminogênio/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Humanos , Cinética , Ligantes , Proteínas Mutantes/química , Biblioteca de Peptídeos , Ligação Proteica , Domínios Proteicos , TermodinâmicaRESUMO
Lamiophlomis rotata (Benth.) Kudo (LR) is a traditional drug used by Chinese minorities such as Tibetans, Mongolians and Na Xi with the beneficial effects of hemostasis and alleviating pain. Flavonoids ingredients (P(1)), iridoid glycosides ingredients (P(2)) and maximus polarity components ingredients (P(3)) were isolated from the aqueous extract of LR (AELR) with polyamide and macroporous adsorptive resins chromatographic columns. The hemostatic activity of these ingredients was estimated by the changes in bleeding time (BT), clotting time (CT) and blood coagulation parameters in mice or rats. RP-HPLC was used to analyze the chemical composition of P(2). As a result, AELR and P(2) significantly shortened BT, CT and thrombin time (TT), and increased fibrinogen (FIB), but P(1) and P(3) showed no hemostatic effect during the experiment. Moreover, P(2) showed satisfactory hemostatic effect with dose-effect relationship and low toxicity in mice. 8-Dehydroxy shanzhiside, phloyoside II, shanzhiside methylester, loganin, and 8-O-acetylshanzhiside methylester were detected as the main iridoid glycosides in P(2) by RP-HPLC. Our results suggest that iridoid glycosides may be the hemostatic activity ingredients of L. rotata and are a potential hemostatic medicine.