Inhibitory Concentration Research Articles

Chemical composition, in vitro and in silico activity of the methanolic extract derived from Vassobia breviflora against clinically relevant bacteria

ABSTRACT This study aimed to identify chemical compounds derived from Vassobia breviflora methanolic extract using ESI-ToF-MS and their antioxidant potential activity utilizing the following methods: total phenols, DPPH, and ABTS•+. The MTT assay measured cytotoxic activity, while DCFH-DA and nitric oxide assays were employed to determine reactive oxygen species (ROS) and reactive nitrogen species (RNS) levels using African green monkey kidney (VERO) and human keratinocyte (HaCat) cell lines. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were assessed in seven clinical isolates and nine ATCC strains. Biofilm inhibition was tested against four biofilm-forming strains. The antioxidant properties of the methanolic extract were identified as follows: 35.74 mg GAE/g (gallic acid equivalents)/g for total phenols, 10.5 µg/ml for DPPH, and 50.68 µmol trolox/µg for ABTS•+. The mean inhibitory concentration (IC50) values were 622.86 µg/ml (VERO) and 784.33 µg/ml (HaCat). These concentrations did not markedly alter levels of ROS and RNS. Conversely, Bacillus cereus β-hemolytic displayed higher sensitivity to the extract, with MIC of 64 µg/ml and MBC of 128 µg/ml. Enterococcus faecium exhibited the lowest biofilm formation among the tested bacteria. The studied plant exhibited activity against all bacterial strains at concentrations lower than the IC50 VERO and HaCat cells, suggesting potential for future studies. Data present a comprehensive molecular docking analysis against the HlyIIR protein (PDB ID: 2FX0) and determined antimicrobial and endocrine-modulating potentials. Notably, lancifodilactone I and nicandrin B demonstrated the strongest binding affinities, with binding energies of −9.8 kcal/mol and −8.3 kcal/mol, respectively, and demonstrated significant antimicrobial effects against B. cereus. In addition, several compounds showed potential interactions with nuclear receptors, indicating potential endocrine-modulating effects. These findings provide insights into developing target-specific antimicrobial therapies and endocrine-modulating agents.

Impact of reporting rapid susceptibility results in Gram negative bloodstream infections: a real world prospective study.

Mortality and morbidity of patients with bloodstream infection (BSI) remain high despite advances in diagnostic methods and efforts to speed up reporting. This study investigated the impact of reporting rapid Minimum Inhibitory Concentration (MIC)-results in Gram negative BSIs with the ASTar system (Q-linea, Uppsala, Sweden) on the adaptation of empirically started antimicrobial therapy. We performed a real-world study during which antimicrobial susceptibility testing (AST) results were instantly reported to the treating physician in an established multidisciplinary antimicrobial stewardship setting. Consecutive patients with Gram negative bacteremia were included in the study (monomicrobial Gram stain, life expectancy of at least 48h and flagging positive before 2 PM). Rapid AST (RAST) reporting with ASTar was added on top of the standard workflow. Technical performance of the system was evaluated as well as the impact on antimicrobial treatment and timelines of achieving effective and optimal antimicrobial therapy. A total of 79 analyses were performed in 77 patients, of which 68 episodes were eligible for analysis. A categorical agreement was observed in 97,5% of 1160 MIC results without false susceptible results. All patients on ineffective empirical therapy (12/68) were switched after a median time of approximately one hour (5min - 15h) after communication of the result. Furthermore, 20/55 non-optimal therapies were adapted within a median period of 3h after communication. The implementation of rapid MICs, measured by the ASTar system, in our low antimicrobial resistance setting with elaborate antimicrobial guidelines, was easy and led to early adaptation of empirical treatment in 32/55 instances (12 ineffective and 20 non-optimal therapy). NCT06218277 (date of registration: 18-12-2023).

Rhanterium Epapposum Essential Oil and Its Primary Compounds Control Infection, Inflammation, and Serum Electrolyte Imbalance in Mice with Giardiasis.

The present experimental study seeks to evaluate the in vitro and in vivo effects, as well as the potential mechanisms of action, of Rhanterium epapposum essential oil (REE) and its main constituents against Giardia lamblia infection. The analysis of REE was performed using the Gas Chromatography-Mass Spectrometry (GC-MS) detector. The in vitro effects of REE and its main constituents on viability of G. lamblia cysts and the human intestinal epithelial cell line, as well as their effects on plasma membrane permeability, the reactive oxygen species (ROS) generation, and trophozoite adherence were assessed by MTT assay. Effects of oral administration of REE and its main constituents at doses 10 and 20mg/kg on the number of Giardia cysts, the serum level of electrolytes of sodium (Na+) and potassium (K+), as well as the gene expression of inflammatory genes of TNF-α, IL-1β, IL-10, NF-κB p65, and Toll-like receptor 4 (TLR4)) were assessed. The 50% inhibitory concentrations (IC50) value of REE, MC, CP, LN and MTZ against G. lamblia cysts was 26.7, 32.1, 35.3, 45.1, and 42.1µg/mL, respectively; indicated that REE, MC, and CP displayed high antigiardial effects in comparison with MTZ. The obtained 50% cytotoxic concentration (CC50) value of REE, MC, CP, LN, and MTZ on HIEC-6 cells was 279.1, 363.4, 394.2, 478.3, and 422.1µg/mL, respectively. REE and its main compounds significantly (p < 0.001) increased the plasma membrane permeability and ROS generation in Giardia trophozoites, while, reduced the Giardia trophozoites adherence. In vivo, REE, MC, CP, and LN mainly at the dose of 20mg/kg considerably reduced the number and viability of Giardia cysts, modulated the serum level of electrolytes Na and K in the infected mice compared with the mice treated with MTZ (P < 0.01); whereas inhibited the inflammation cytokines in the infected mice compared with the mice treated with MTZ (p < 0.001). The current investigation showed that R. epapposum essential oil and its main compounds controlled the Giardia infection in mice by inhibiting inflammation, and serum electrolyte imbalance. After confirmation in further studies, these compounds may be considered for development as a novel therapeutic option for the treatment of giardiasis.

Design, Synthesis, and Biological Evaluation of Thieno[3,2-d]pyrimidine Derivatives as the First Bifunctional PI3Kδ Isoform Selective/Bromodomain and Extra-Terminal Inhibitors.

The concomitant inhibition of PI3Kδ and bromodomain and extra-terminal (BET) that exerts a synergistic effect on the B-cell receptor signaling pathway provides a new strategy for the treatment of aggressive diffuse large B-cell lymphoma (DLBCL). Herein, a merged pharmacophore strategy was utilized to discover a series of thieno[3,2-d]pyrimidine derivatives as the first-in-class bifunctional PI3Kδ-BET inhibitors. Through optimization, a highly potent compound (10b) was identified to possess excellent and balanced activities against PI3Kδ [inhibitory concentration (IC50) = 112 ± 8 nM] and BRD4-BD1 (IC50 = 19 ± 1 nM) and exhibited strong antiproliferative activities in DLBCL cells. Notably, this compound demonstrated good PI3Kδ selectivity over other kinases with minimal cytotoxicity in normal cells. Moreover, 10b has a good oral pharmacokinetic profile in mice and achieves outstanding antitumor activity in the SU-DHL-6 xenograft model. Taken together, these results indicate that targeting PI3Kδ and BET with a bifunctional inhibitor is a promising strategy to treat DLBCL.

Factoring fu Variability Into Estimates of Unbound Drug Concentrations Negatively Biases the MIC Versus% Probability of Target Attainment Relationship of Antimicrobial Agents.

The clinical breakpoint for a drug-pathogen combination reflects the drug susceptibility of the pathogen wild-type population, the location of the infection, the integrity of the host immune response, and the drug-pathogen pharmacokinetic (PK)/pharmacodynamic (PD) relationship. That PK/PD relationship, along with the population variability in drug exposure, is used to determine the probability of target attainment (PTA) of the PK/PD index at a specified minimum inhibitory concentration (MIC) for a selected target value. The PTA is used to identify the pharmacodynamic cutoff value (COPD), which is one of the three components used to establish the clinical breakpoint. A challenge encountered when defining the COPD is that the available PK information typically reflects total (free plus protein-bound) plasma concentrations. However, it is the unbound drug concentrations that exert the therapeutic effects and how the population fraction unbound (fu) incorporated into the COPD assessments can markedly influence the COPD. Factors examined included the estimated population fu mean (risk of bias) and the incorporation of estimated fu population variability into the Monte Carlo simulations when converting total to unbound plasma concentrations (risk of inflating variability). In this in silico study, the drug fu, systemic clearance, and the variability of both were altered so that the relative impact of each could be explored. We demonstrate that incorporating fu variability into the estimation of fAUCback can bias the COPD assessment and that the magnitude of bias reflects the relative variability in systemic clearance and fu.

Evaluation of MRX PT DOAC as a new screening method for detecting interferences in thrombophilia analyses

Background Direct oral anticoagulants (DOACs) can interfere with coagulation analyses, causing erroneous results such as false-positive lupus anticoagulant and false-normal antithrombin, threatening patient safety when overlooked. A test using a prothrombin time quotient method to detect DOAC presence in plasma samples is now commercially available, the MRX PT DOAC, with the result expressed as Clot Time Ratio (CTR). Objectives Evaluate the ability of MRX PT DOAC to identify interfering apixaban or rivaroxaban concentrations, identify non-interfering or interfering patient samples, and detect whether a patient is on DOAC treatment. Methods An MRX PT DOAC reference interval was established, and MRX PT DOAC results related to FXa inhibitor concentrations. MRX PT DOAC patient plasma results were related to indications of analytical interference with lupus anticoagulant and antithrombin analyses and with the patients’ anticoagulant drug use, according to medical records. Results The MRX PT DOAC CTR reference interval was 0.98–1.38. MRX PT DOAC apixaban and rivaroxaban interference detection sensitivity was 1.00 (0.96 − 1.0). For subgroups from 315 patient plasma samples, the negative predictive values estimates were 0.84 or above (95% confidence interval minimum 0.64) for excluding analysis interference with the lupus anticoagulant and antithrombin analyses and for excluding DOAC treatment as per medical records. All 9 interference-indicating DOAC samples were identified for the lupus anticoagulant analyses, 5 out of 11 for antithrombin. Conclusions The MRX PT DOAC is a potential screening tool for interference. Confirming results in a larger DOAC patient group and further investigating the antithrombin interference detection uncertainty is important.

Antifungal susceptibility testing and determination of local epidemiological cut-off values for Candida species isolated from women with vulvovaginal candidiasis.

The lack of clinical breakpoints and epidemiological cut-off values (ECOFFs) for antifungals prescribed for vulvovaginal candidiasis (VVC) make interpretation of antifungal susceptibility data difficult. This leads to empirical prescribing, poor clinical management and emergence of resistance. The in vitro susceptibilities of 152 Candida albicans, 105 Candida parapsilosis, 31 Nakaseomyces glabratus, and 8 Pichia kudriavzevii VVC isolates against eight antifungals, were determined according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) E.Def 7.4. The minimum inhibitory concentration (MIC) distributions were analyzed and local ECOFFs were determined visually and statistically. The in vitro activity of azoles was correlated with fluconazole susceptibility and clinical data were evaluated. The MICs of various azoles showed a significant correlation with the MICs of fluconazole and fluconazole non-wild type (WT) isolates had significantly higher MICs for other azoles. The estimated local ECOFFs for C. albicans were 0.016 mg/L (ketoconazole, clotrimazole), 0.06 mg/L (miconazole, econazole, itraconazole), 1 mg/L (fenticonazole), and 3,200 mg/L (boric acid). For C. parapsilosis, local ECOFFs were 0.06 mg/L (ketoconazole, clotrimazole, itraconazole), 1 mg/L (miconazole, econazole), 2 mg/L (fenticonazole), and 3,200 mg/L (boric acid). For N. glabratus, they were 1 mg/L (ketoconazole, clotrimazole, miconazole, itraconazole), 2 mg/L (econazole, fenticonazole), and 12,800 mg/L (boric acid). Non-WT isolates were detected for azoles in N. glabratus (10%-35%), C. albicans (5%-16%), and C. parapsilosis (≤ 3%). All isolates were WT for boric acid. Local ECOFFs were established for three major Candida species causing VVC, guiding the identification of non-WT isolates potentially associated with treatment failure.IMPORTANCEThe interpretation of in vitro susceptibility data of Candida isolates from women with vulvovaginal candidiasis (VVC) is challenging due to the lack of clinical breakpoints (CBPs) and epidemiological cut-off values (ECOFFs) for drugs used in VVC. In the present study, local ECOFFs were established for three major Candida species causing VVC, guiding the identification of non-wild type isolates potentially associated with treatment failure. This paper provides the framework for developing ECOFFs and ultimately CBPs that would help guide antifungal therapy of VVC.

Evaluation of the recovery effects of antibiotic-resistant lactiplantibacillus plantarum subsp. Plantarum ATCC14917 on the antibiotic-disturbed intestinal microbiota using a mice model.

Supplementing Lactobacillus alongside antibiotic treatment was a curative strategy to modulate gut microbiota and alleviate antibiotic-associated dysbiosis. But the lactobacilli that are used as probiotics are sensitive or have a low level of resistance to antibiotics, so they usually cannot achieve their beneficial effect, since they are killed by the applied antibiotics. This work aimed to develop the highly resistant Lactiplantibacillus plantarum subsp. plantarum ATCC14917 to cephalexin and evaluate its recovery effects of antibiotic-resistant L. plantarum on the antibiotic-disturbed intestinal microbiota using a mice model. After successive growth in LSM broth containing a gradually increasing concentration of cephalexin for 70 days, the minimum inhibitory concentration (MIC) of L. plantarum ATCC14917 to cephalexin significantly increased from 16 μg·mL-1 to 8192 μg·mL-1, but stabilized on 4096 μg·mL-1. After sequencing and sequence analysis, no mutated genes were detected on mobile elements, showing that horizontal transfer of mutated genes could not occur. Compared to the control group (Con), feeding mice with cephalexin (1mg·mL-1; Cep) led to a decrease in alpha diversity. However, concurrently used cephalexin and L. plantarum (Cep+LpR) increased the alpha diversity in both microbial richness and diversity. The Cep+LpR group showed a lowest distance with the Con group than either Cep or Cep+LpS groups, suggesting that resistant L. plantarum treatment was more effective than the original strain for the recovery of intestinal microbiota. Compared to the cephalexin-treated group, concurrent ingestion of cephalexin together with resistant L. plantarum significantly increased the proportion of beneficial bacteria, decreased Firmicutes/Bacteroidetes ratio and abundance of potential pathogens. The use of antibiotic-resistant Lactiplantibacillus plantarum ATCC14917 contributed to a much faster and richer recovery of the gut microbiota disturbed by antibiotic treatment compared to original strain.

Beta-sitosterol regulates PTGS1 to inhibit gastric cancer cell proliferation and angiogenesis.

Gastric cancer (GC) is the third leading culprit of cancer-related deaths around the world. Beta-sitosterol (BS) is an important phytosterol that has been proven to have anti-proliferative effects on GC and other tumors. However, mechanisms and targets of BS in cancer are rarely explored. In this investigation, the targets of BS in the treatment of GC were analyzed by network pharmacology. Molecular docking and cellular thermal shift assay were introduced to validate the binding relationship between BS and PTGS1. The impacts of BS on GC cell viability, half maximal inhibitory concentration, proliferation ability, apoptosis level, and angiogenesis ability were detected by using Cell Counting Kit-8, clone formation assay, flow cytometry, and angiogenesis experiment, respectively. In addition, the expression levels of angiogenic factors (VEGF, FGF, PAI-1) were detected by using western blot. In this project, through cell experiments, PTGS1 was identified as a protein that directly binds to BS. In vitro cell experiments revealed that BS promoted apoptosis and inhibited GC cell proliferation and angiogenesis. Importantly, treatment with BS attenuated the promoting influence of PTGS1 overexpression on GC cell proliferation and angiogenesis. This investigation highlighted PTGS1 as the target of BS in GC cells. BS can regulate PTGS1 to inhibit GC cell proliferation and angiogenesis, providing new evidence for the potential use of BS as a therapeutic agent for GC.

Rapid on-site detection of imazaquin residue in corn and soybeans using an immunochromatographic assay.

Imazaquin (IMQ) is an imidazolinone group herbicide widely used for weed control around the world. Due to excessive use during crop production, IMQ can accumulate in corn and soybeans, positing a potential threat to human health. In this study, a hapten that had high specificity and sensitivity was designed using computer-simulated technology. A monoclonal antibody (mAb) was synthesized with a half inhibitory concentration of 0.98 ng mL-1. The mAb was incorporated into an immunochromatographic assay (ICA) for the detection of IMQ in corn and soybeans. The visual limit of detection was 10 μg kg-1 in corn with a linear range of 3.85-208.26 μg kg-1 and 5 μg kg-1 in soybeans with a linear range of 3.78-106.71 μg kg-1. Additionally, the ICA strips had excellent recovery rates, and the results were confirmed by liquid chromatography tandem mass spectrometry. Our study developed a method for the rapid on-site detection of IMQ residues in corn and soybeans.

Essential Oils as Antimicrobials against Acinetobacter baumannii: Experimental and Literature Data to Definite Predictive Quantitative Composition-Activity Relationship Models Using Machine Learning Algorithms.

Essential oils (EOs) exhibit a broad spectrum of biological activities; however, their clinical application is hindered by challenges, such as variability in chemical composition and chemical/physical instability. A critical limitation is the lack of chemical consistency across EO samples, which impedes standardization. Despite this, evidence suggests that EOs with differing chemical profiles often display similar (micro)biological activities, raising the possibility of standardizing EOs based on their biological effects rather than their chemical composition. This study explored the relationship between EO chemical composition and antibacterial activity against carbapenem-resistant Acinetobacter baumannii. A dataset comprising 82 EOs with known minimal inhibitory concentration values was compiled using both experimental results and literature data sourced from the AI4EssOil database (https://www.ai4essoil.com). Machine learning classification algorithms including Support Vector Machines, Random Forest, Gradient Boosting, Decision Trees, and K-Nearest Neighbors were employed to generate quantitative composition-activity relationship models. Model performance was assessed using internal and external prediction accuracy metrics with the Matthews correlation coefficient as the primary evaluation metrics. Features importance analysis, based on the Skater methodology, identified key chemical components influencing EO activity. The single chemical components limonene, eucalyptol, alpha-pinene, linalool, beta-caryophyllene, nerol, beta-pinene, neral, and carvacrol were highlighted as critical to biological efficacy. The predictive capacity of the ML models was validated against a test set of freshly extracted and chemically characterized EOs. The models demonstrated a 91% prediction accuracy for new EO samples, and a strong correlation was observed between predicted features importance and experimental inhibitory values for six selected pure compounds (limonene, eucalyptol, alpha-pinene, linalool, carvacrol, and thymol). Additionally, the machine learning approach was extended to cytotoxicity data from 3T3-Swiss fibroblasts for 61 EOs. The analysis revealed the potential to design EOs with both high antibacterial activity and low cytotoxicity through blending or selective enrichment with identified key components. These findings pave the way for biologically standardized EOs, enabling their rational design and optimization for clinical applications.

Hyaluronic acid-silybin conjugate for the preparation of multifunctional, biomimetic, vancomycin-loaded self-assembled polymersomes against bacterial sepsis.

Sepsis, a life-threatening disruption, remains a significant global healthcare challenge that urgently needs novel strategies to improve management. This study aimed to develop multifunctional vancomycin-loaded polymersomes (VCM-HA-SIL-Ps) using a novel hyaluronic acid-silybin (HA-SIL) conjugate to target the TLR inflammatory pathway and enhance VCM's efficacy against bacterial sepsis. HA-SIL was synthesized and characterized by FT-IR, UV-Vis spectroscopy, and 1H NMR. The biomimetic properties of HA-SIL were confirmed via in silico (-73.35kcal/mol) and in vitro (dissociation constant=2.872μM) binding affinity studies against TLR2. VCM-HA-SIL-Ps exhibited appropriate physicochemical properties, biocompatibility, and stability. VCM-HA-SIL-Ps sustained VCM release for 48h, achieving 73.38% cumulative release. In vitro antibacterial studies showed that VCM-HA-SIL-Ps had superior minimum inhibitory concentration against sensitive and resistant Staphylococcus aureus and faster bacterial killing, compared to free VCM. Additionally, VCM-HA-SIL-Ps demonstrated excellent DPPH radicals scavenging and effective anti-inflammatory activity on bacterial toxin-stimulated cells. Finally, in a mouse model of MRSA-induced sepsis, VCM-HA-SIL-Ps achieved 100% bacterial eradication, significantly reduced pro-inflammatory markers (IL-6, TNF-α, IL-1β by 2.9-, 1.8-, and 5-fold, respectively), and minimized organ damage. Collectively, these findings demonstrate the potential of HA-SIL as a novel multifunctional adjuvant for effective antibiotic delivery against bacterial sepsis.

Palmarosa essential oil inhibits the growth of dandruff-associated microbes by increasing ROS production and modulating the efflux pump.

We investigated the antimicrobial efficacy of seven essential oils from four plant families-Lamiaceae, Asteraceae, Zingiberaceae, and Poaceae-against microbes associated with dandruff. The antimicrobial effectiveness of these essential oils was assessed using paper disk agar diffusion and broth micro-dilution techniques. The results demonstrated that two of the essential oils significantly inhibited the growth of dandruff-associated microorganisms, with inhibition zones ranging from 5 ± 1.81 mm to 29.4 ± 2.70 mm in diameter. Among the tested essential oils, Palmarosa (Cymbopogon martinii) exhibited the highest antimicrobial potency, showing a minimum inhibitory concentration (MIC) between 0.27 and 0.55 mg/mL for the fungi Malassezia furfur and Candida albicans, as well as for the bacterium Staphylococcus epidermidis. The essential oil displayed fungicidal activity within the range of 0.55 to 2.2 mg/mL and bactericidal activity at 0.55 mg/mL. Additionally, post-treatment effects were evaluated by monitoring the re-growth of fungal and bacterial cells after exposure to Palmarosa essential oil. The results revealed significant retardation of the growth of M. furfur for up to 7 h at 2 × MIC and S. epidermidis for up to 5 h at higher concentrations (1 × MIC and 2 × MIC). The study also found that Palmarosa essential oil-induced reactive oxygen species (ROS) production and altered the integrity of microbial membranes, although it did not impact the concentrations of ergosterol and sorbitol. Regarding safety, topical application of Palmarosa essential oil (at concentrations of 1X, 10X, and 20X MIC) on rats and rabbits caused no irritation, and no sub-acute toxic effects were observed either on the skin or systemically. These promising results suggest that Palmarosa essential oil has the potential to be developed into an effective and safe formulation for treating dandruff associated with microbial infections. Further studies could help solidify its clinical applications.

Enhanced antitumor efficacy of nanostructured lipid carrier co-loaded with docetaxel and 5-fluorouracil for targeted gastric cancer therapy.

This study presents nanostructured lipid carrier (NLC) co-loaded with Docetaxel (DCT) and 5-Fluorouracil (5-FU) as a targeted therapeutic approach for gastric cancer (GC). Using nanoprecipitation, NLC-DCT/5-FU were synthesized and exhibited an average particle size of 215.3 ± 10.4nm, a polydispersity index (PDI) of 0.29, and a zeta potential of -17.1mV. Encapsulation efficiency reached 95.9% for DCT and 5-FU, with a loading efficiency of 11.2%. In vitro release studies demonstrated a biphasic release profile, with an initial burst and sustained release, achieving 85.6% DCT and 75.8% 5-FU release over 72h. Cytotoxicity assays in MKN45 cells showed a significantly lower half-maximal inhibitory concentration (IC50) for NLC-DCT/5-FU (0.3µM) compared to free DCT (3.9µM) and free 5-FU (19.5µM), indicating enhanced efficacy. In vivo evaluation in a GC mouse model confirmed substantial tumor volume reduction to 213 mm3 with NLC-DCT/5-FU treatment, compared to 432mm3 with the free-drug combination. Systemic safety assessment showed minimal adverse effects, suggesting the nanoparticles' enhanced therapeutic index. These results demonstrate that NLC-based co-delivery systems could substantially improve the clinical outcomes of GC therapy.

Quinacrine Inhibits Hepatocellular Carcinoma Growth and Enhances the Anti-HCC Effects of Lenvatinib.

Hepatocellular Carcinoma (HCC) is a highly prevalent cancer worldwide, necessitating effective treatment options. However, current treatments do not provide satisfactory results. Quinacrine, a synthetic drug belonging to the 9-aminoacridine family, has demonstrated promising antitumor effects. The objective of the current study is to evaluate the anti-HCC effect of Quinacrine and explore whether quinacrine can improve the anti-HCC response of lenvatinib in vitro and in vivo. The HepG2 and MHCC-97H cells were treated with Quinacrine. Cell proliferation and cell apoptosis were assessed using the Cell Counting Kit-8 (CCK8) Assay, Colony Formation Assay, and Annexin V/7-AAD staining method. The invasion and migratory ability of HepG2 and MHCC-97H cells were assessed by Transwell Assay. The level of ROS of HCC cells was measured using a ROS-kit by Flow cytometric analysis. Besides, an in vivo study was performed in the Balb/c nude mice bearing MHCC-97H tumors to analyze the function of Quinacrine in tumor growth. Quinacrine can decrease cell viability in HepG2 and MHCC-97H cells, but not affect LO2 cells. Quinacrine impaired the colony formation, invasion and migratory ability in half-maximal inhibitory concentration (IC50). Quinacrine also significantly induced apoptosis in HepG2 and MHCC-97H cells in a concentrationdependent manner. On the one hand, ROS was significantly up-regulated in HCC cells after quinacrine treatment. On the other hand, We found quinacrine blocked autophagy flux in HepG2 and MHCC-97H cells. Moreover, Quinacrine significantly enhances the anti-HCC efficacy of lenvatinib in vitro. In the mouse MHCC-97H model, We found that combination therapy with Quinacrine and lenvatinib resulted in a smaller tumor volume and weight than inoculated with lenvatinib alone. Our findings demonstrated that quinacrine exerts anti-HCC effects and sensitizes hepatocellular carcinoma to lenvatinib. Collectively, our study provides novel therapeutic insights for managing HCC and offers a valuable strategy for future clinical interventions in this field.

Comparative study of the structure effect on the inhibition efficiency of three hydroxybenzylidene isonicotinohydrazide derivatives for corrosion carbon steel in a 1 M HCl solution: experimental and theoretical studies

ABSTRACT The inhibition effects of three newly synthesised hydroxybenzylidene isonicotinohydrazide derivatives, namely, (E)-N′-(2-hydroxybenzylidene) isonicotinohydrazide (ISO 2OH)), (E)-N′-(4-hydroxybenzylidene) isonicotinohydrazide (ISO 4OH)) and (E)-N′-(2,4-dihydroxybenzylidene) isonicotinohydrazide (ISO 2.4OH)) for carbon steel (CS) corrosion in 1 M HCl medium were studied. For this study, potentiodynamic polarisation (PDP), electrochemical impedance spectroscopy (EIS), surface scanning electron microscopy (SEM) analysis coupled with energy dispersive spectroscopy (EDX) analysis and computational density functional theory (DFT) and molecular dynamic (MD) simulations methods were carried out. It is found that the inhibition efficiency increases with increasing inhibitors concentrations, where the best value is about 95% at 10−3 M ISO 2.4OH. The PDP studies indicated that hydroxybenzylidene isonicotinohydrazide derivatives react as mixed-type inhibitors. However, it found that the adsorption of these inhibitor molecules on the CS obeys the Langmuir isotherm. SEM/EDX analysis of the CS specimens demonstrated that the hydroxybenzylidene isonicotinohydrazide derivatives were adsorbed and formed a protective layer on the CS area, where the UV-vis analysis revealed the formation of inhibitor-metallic complexes in the electrolyte. Finally, theoretical calculations using DFT and MDS methods have revealed good correlations between multiple chemical descriptors and the inhibition properties of the studied hydroxybenzylidene isonicotinohydrazide derivatives molecules, as well as their interaction modes with the CS surface.

Risk assessment of chlorophenols (CPs) exposure in vitro:Inhibition of sulfotransferases (SULTs) activity.

Chlorophenols (CPs) are common organic pollutants widely used in many industries. The current study seeks to examine the inhibition of sulfotransferases (SULTs) by CPs. Four SULT isoforms were significantly inhibited by multiply CPs. Furthermore, half inhibition concentration (IC50) was calculated to be 0.31 μM, 0.11 μM and 1.86 μM for the inhibition of PCP (pentachlorophenol) towards SULT1A1, SULT1B1 and SULT1E1. PCP showed competitive inhibition towards SULT1B1 and SULT1E1.The inhibition kinetics (inhibition type and parameters (Ki)) values were calculated to be 0.34 μM and 0.56 μM for the inhibition of PCP towards SULT1B1 and SULT1E1, respectively. In silico docking was used to explain the inhibition difference among CPs. The binding free energy between 4-CP and SULT1A3 was -4.92 kcal/mol, and the binding free energy between 2.4-DCP and SULT1A3 was -5.63 kcal/mol. Therefore, 2.4-DCP exerted stronger inhibition activity towards SULT1A3 compared with 4-CP, which can well explain the experimental result. These results are crucial for exploring the risks associated with CPs exposure from a novel perspective.

Thymol as a Novel Plant-Derived Antibacterial Agent for Suppressing Xanthomonas citri pv. malvacearum in Cotton.

Xanthomonas citri pv. malvacearum (Xcm) associated with bacterial blight disease is a significant and widespread pathogen affecting cotton worldwide. The excessive use of harmful chemicals to control plant pathogens has exerted a negative impact on environmental safety. Thymol is a monoterpene phenol present in the essential oils of plants belonging to Lamiaceae family. In this study the antimicrobial activity of thymol was evaluated against Xcm. The minimum inhibitory concentration (MIC) and 99.9% bactericidal concentration (MBC) of thymol against Xcm were 2 and 4mg/mL, respectively. The effect of MIC and MBC of thymol against Xcm was assessed on the Luria-Bertani medium. The effect of thymol on intercellular ATP levels, membrane potential, and motility in Xcm was assessed using fluorescence spectrometry for membrane potential and firefly luciferase-based assay for ATP levels. Thymol ruptured the cellular membrane of Xcm, resulting in decreased intracellular ATP concentrations, intracellular leakage of genetic material, and changes in membrane potential. Scanning electron microscopy images supported the impact of thymol on the cell membrane of Xcm. Moreover, thymol inhibited the swimming motility and biofilm formation of Xcm at concentrations equal to or above the MIC and MBC. In contrast, sub-MIC concentrations of thymol had little to no impact on the virulence of Xcm. In conclusion, thymol demonstrated the potential as a strong bactericidal compound against Xcm.

Preparation, Antifungal Activity Evaluation, and Mechanistic Studies of Unique and Structurally Novel Pyrazole-Heterocyclic-Amide Analogues.

Thirty-six novel pyrazole-heterocyclic-amide analogues were designed, synthesized, and characterized. The bioassay results showed that most target compounds exhibited good fungicidal activities against Rhizoctonia solani, Gibberella zeae, Pseudoperonospora cubensis, Helminthosporium maydis, and Coniothyrium diplodiella at 20 μg/mL. Compounds 6d, 6f, 6l, and 6j possessed better fungicidal activities than the commercial fungicide prochloraz against H. maydis. Their half maximal effective concentration (EC50) values were 0.47, 0.26, 0.58, and 0.69 μg/mL, respectively, and the EC50 value of prochloraz was 0.77 μg/mL. Furthermore, the inhibitory activities for the bioactive compounds were determined against sterol 14α-demethylase (CYP51), the results displayed that they had prominent activities, compounds 6d, 6f, 6l, and 6j also showed better inhibitory activities than prochloraz against CYP51, their half maximal inhibitory concentration (IC50) values were 0.543, 0.29, 0.77, 0.66, and 0.86 μg/mL, respectively. The results of molecular dynamics simulations exhibited that compound 6f displayed stronger affinity to CYP51 than prochloraz, and estimated ΔGbind values of -44.9 and -37.2 kcal/mol were found for 6f and prochloraz, respectively.

Evaluation of the antibacterial and inhibitory activity of the NorA and TetK efflux pumps of Staphylococcus aureus by p-coumaric acid.

The NorA and TetK efflux pumps mediate resistance to fluoroquinolone and tetracycline antibiotics by actively extruding these compounds and reducing their intracellular concentrations. Consequently, intense research has focused on inhibiting these efflux mechanisms using antimicrobial agents derived from natural or synthetic sources. This study used Fourier transform infrared spectroscopy (ATR-FTIR) to analyze the various functional groups present in p-coumaric acid. We also investigated the antibacterial activity of p-coumaric acid on strains of Staphylococcus aureus carrying the NorA and TetK efflux pumps, as well as the compound's ability to increase the fluorescence of ethidium bromide (EtBr) and Sytox Green. In addition, the interactions of this compound with NorA were analyzed using molecular docking, and its pharmacokinetic properties were evaluated using ADMET (Absorption, Distribution, Metabolism, Excretion and Toxicity) modeling. The results revealed that p-coumaric acid exhibited no direct antibacterial activity against the tested Staphylococcus aureus strains. However, significant reductions in the minimum inhibitory concentrations (MICs) of norfloxacin and EtBr, both used as NorA substrates, were observed when combined with p-coumaric acid. It was also observed that p-coumaric acid increased the fluorescence emission of EtBr and Sytox Green in strains 1199 and 1199B, suggesting the inhibition of the efflux mechanism and enhanced membrane permeabilization in S. aureus. The in silico analysis demonstrated that p-coumaric acid exhibits a favorable binding energy with NorA, comparable to that of chlorpromazine. These results position p-coumaric acid as a promising antibiotic adjuvant and efflux inhibitor in strains harboring NorA.