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Cucurbit[n]urils (CB[n], n = 5–8) are the most important class of host molecules that are widely applied in various important applications. Until now, no sensitive sensor has been developed exclusively for detecting cucurbiturils. Here, we have utilized the supramolecular assembly of acriflavine and graphene oxide (ACF-GO) as a fluorescence sensor for the detection of cucurbituril family members such as CB[5], CB[6] and CB[7] with the discrimination of fluorescence intensities. Among them, CB[7] displayed the highest sensitivity, which can be detected as low as nano-molar concentration, and that allowed us to make a facile fluorescence method of detection for CB[7] and other CBs. Supramolecular assembly of acriflavine on the graphene oxide turn-off the fluorescence of acriflavine and upon interaction with cucurbit[7]uril, that released the acriflavine to the solution and turn-on the fluorescence, which allowed to detect the CB[7] to the lowest of nano-molar concentration. [ABSTRACT FROM AUTHOR]

Abstract Acriflavine is a multipurpose drug that shows antibacterial, antiviral, antimalarial, and antifungal activities. The remarkable native fluorescence of acriflavine is exploited in analytical chemistry field as an efficient probe for analysis of pharmaceutical and biological compounds. The fluorescent probe action of acriflavine is based on the remarkable fluorescence turning-off via formation of ion-pair complexes with acidic drugs at a specific pH. Herein, the acidic drug aceclofenac is analysed for the first time using acriflavine as a fluorescent probe. Aceclofenac can form an ion-pair complex with acriflavine at pH 8.5, and hence it partially turns off the fluorescence intensity of acriflavine over a concentration range of 1–20 µg/mL. The fluorescence quenching was monitored at 502 nm following an excitation at 265 or 451 nm. The reaction stoichiometry between acriflavine and aceclofenac was found to be 1:1 using limiting logarithmic method. The type of quenching was confirmed to be static using Stern–Volmer plot. The method showed low values of quantitation limit (0.89 µg/mL) and detection limit (0.29 µg/mL). Moreover, the method was linear (r = 0.9999), accurate, precise (RSD

Introduction: Optic neuritis (ON) is often an early sign of multiple sclerosis (MS), and recent studies show a link between HIF-1 pathway activation and inflammation. This study aimed to determine if inhibition of the HIF-1 pathway using the HIF-1a antagonist acriflavine (ACF) can reduce clinical progression and rescue the ocular phenotype in an experimental autoimmune encephalomyelitis (EAE) ON model. Methods: EAE-related ON was induced in 60 female C57BL/6J mice by immunization with MOG33-55, and 20 EAE mice received daily systemic injections of ACF at 5 mg/kg. Changes in the visual function and structure of ACF-treated EAE mice were compared to those of placebo-injected EAE mice and naïve control mice. Results: ACF treatment improved motor-sensory impairment along with preserving visual acuity and optic nerve function. Analysis of retinal ganglion cell complex alsoshowed preserved thickness correlating with increased survival of retinal ganglion cells and their axons. Optic nerve cell infiltration and magnitude of demyelination were decreased in ACF-treated EAE mice. Subsequent in vitro studies revealed improvements not only attributed to the inhibition of HIF-1 butalso to previously unappreciated interaction with the eIF2a/ATF4 axis in the unfolded protein response pathway. Discussion: This study suggests that ACF treatment is effective in an animal model of MS via its pleiotropic effects on the inhibition of HIF-1 and UPR signaling, and it may be a viable approach to promote rehabilitation in MS. [ABSTRACT FROM AUTHOR]

IntroductionOptic neuritis (ON) is often an early sign of multiple sclerosis (MS), and recent studies show a link between HIF-1 pathway activation and inflammation. This study aimed to determine if inhibition of the HIF-1 pathway using the HIF-1a antagonist acriflavine (ACF) can reduce clinical progression and rescue the ocular phenotype in an experimental autoimmune encephalomyelitis (EAE) ON model.MethodsEAE-related ON was induced in 60 female C57BL/6J mice by immunization with MOG33-55, and 20 EAE mice received daily systemic injections of ACF at 5 mg/kg. Changes in the visual function and structure of ACF-treated EAE mice were compared to those of placebo-injected EAE mice and naïve control mice.ResultsACF treatment improved motor–sensory impairment along with preserving visual acuity and optic nerve function. Analysis of retinal ganglion cell complex alsoshowed preserved thickness correlating with increased survival of retinal ganglion cells and their axons. Optic nerve cell infiltration and magnitude of demyelination were decreased in ACF-treated EAE mice. Subsequent in vitro studies revealed improvements not only attributed to the inhibition of HIF-1 butalso to previously unappreciated interaction with the eIF2a/ATF4 axis in the unfolded protein response pathway.DiscussionThis study suggests that ACF treatment is effective in an animal model of MS via its pleiotropic effects on the inhibition of HIF-1 and UPR signaling, and it may be a viable approach to promote rehabilitation in MS.

Acriflavine is a multipurpose drug that shows antibacterial, antiviral, antimalarial, and antifungal activities. The remarkable native fluorescence of acriflavine is exploited in analytical chemistry field as an efficient probe for analysis of pharmaceutical and biological compounds. The fluorescent probe action of acriflavine is based on the remarkable fluorescence turning-off via formation of ion-pair complexes with acidic drugs at a specific pH. Herein, the acidic drug aceclofenac is analysed for the first time using acriflavine as a fluorescent probe. Aceclofenac can form an ion-pair complex with acriflavine at pH 8.5, and hence it partially turns off the fluorescence intensity of acriflavine over a concentration range of 1–20 µg/mL. The fluorescence quenching was monitored at 502 nm following an excitation at 265 or 451 nm. The reaction stoichiometry between acriflavine and aceclofenac was found to be 1:1 using limiting logarithmic method. The type of quenching was confirmed to be static using Stern–Volmer plot. The method showed low values of quantitation limit (0.89 µg/mL) and detection limit (0.29 µg/mL). Moreover, the method was linear (r = 0.9999), accurate, precise (RSD < 1.7%), robust, and specific. The proposed method was successfully employed to analyse aceclofenac in its dosage forms with high %recovery (98–101%). Additionally, GAPI and AGREE approaches were used to guarantee the suggested techniques' greenness, and the findings showed an excellent level of greenness. [ABSTRACT FROM AUTHOR]

Fungal infections have far-reaching implications that range from severe human disease to a panoply of disruptive agricultural and ecological effects, making it imperative to identify and understand the molecular pathways governing the response to antifungal compounds. In this context, CZT-1 (cell death-activated zinc cluster transcription factor) functions as a master regulator of cell death and drug susceptibility in Neurospora crassa. Here we provide evidence indicating that czt-1 is allelic to acr-3, a previously described locus that we now found to harbor a point mutation in its coding sequence. This nonsynonymous amino acid substitution in a low complexity region of CZT-1/ACR-3 caused a robust gain-of-function that led to reduced sensitivity to acriflavine and staurosporine, and increased expression of the drug efflux pump abc-3. Thus, accumulating evidence shows that CZT-1 is an important broad regulator of the cellular response to various antifungal compounds that appear to share common molecular targets.

Cutaneous burn wounds are a common and troublesome critical issue of public health. Over the last decade, many researchers have investigated the development of novel therapeutic modalities which are capable of fully regeneration and reinstatement of structure and function of the skin with no or limited scar formation. Novel pharmaceutical carriers are offering a potential platform to deliver the drug effectively and to overcome the limitation associated with conventional wound dressings. The aim of this study was to investigate a pharmaceutical acriflavine-loaded polycaprolactone nanoemulsion (ACR-PCL-NE) for burn wound healing. Nanoemulsion was prepared by using the double emulsion solvent evaporation technique and it was subjected to thermodynamic stability testing, droplet size, polydispersity, zeta potential, pH, and surface morphology analysis. The in vivo study was performed to evaluate the efficacy of nanoemulsion using Sprague-Dawley rats as an animal model. The results of this study revealed that the optimized nanoemulsion was stable and had desirable physicochemical properties. The pH was about 4.02 at 25 °C and the particle size was found to be in the range of 302 ± 4.62 nm while the zeta potential was −7.8 ± 1.22 mV and the polydispersity index of 0.221 ± 0.017. The wound regeneration process was evaluated in vivo by different techniques, the formulation group (FG) showed high wound healing potential as compared to the standard group (SD) and control group (CG). These findings reveal that this nanoemulsion formulation can be used effectively for wound healing.

Context: Hypoxia is commonly observed in multiple aggressive cancers. Its role remains unclear in the biology and therapy of dedifferentiated thyroid cancer (DDTC). Objective: We aimed to elucidate hypoxia’s roles in DDTC tumor biology. Methods: We discovered and confirmed hypoxia’s correlation with dedifferentiation status, poor prognoses, and immune checkpoints in thyroid cancer using transcriptome data from our center and Gene Expression Omnibus (GEO) database. Then, the effect of targeting hypoxia was investigated via treating anaplastic thyroid cancer (ATC) cells with acriflavine (ACF) in vitro and in vivo, and hypoxia was analyzed for its association with response to immunotherapy in patients. Results: Hypoxia score was positively associated with dedifferentiation status, and high hypoxia score significantly correlated with reduced overall survival, TP53 mutation, and elevated expression of immunosuppression-related markers in DDTC. ACF and siRNA targeting HIF-1α significantly suppressed growth and proliferation of thyroid cancer cells in vitro and in vivo, and reduced c-MYC and PDL1 expression in ATC. HIF-1α showed a positive correlation with PDL1 expression in DDTC. Integrated analyses of phosphoproteome and RNA sequencing data revealed that ACF’s target was connected with differentiation genes and immune checkpoints via tumor-related kinases in ATC. Furthermore, hypoxia score was associated with immunotherapeutic response in some cancer types. Conclusion: Hypoxia score serves as a significant indicator for dedifferentiation status, prognoses, and immunotherapeutic response predicted by Tumor Immune Dysfunction and Exclusion in DDTC patients. Targeting hypoxia by ACF is useful to alleviate aggressive phenotype of ATC in a preclinical model of DDTC. [ABSTRACT FROM AUTHOR]

Cutaneous burn wounds are a common and troublesome critical issue of public health. Over the last decade, many researchers have investigated the development of novel therapeutic modalities which are capable of fully regeneration and reinstatement of structure and function of the skin with no or limited scar formation. Novel pharmaceutical carriers are offering a potential platform to deliver the drug effectively and to overcome the limitation associated with conventional wound dressings. The aim of this study was to investigate a pharmaceutical acriflavine-loaded polycaprolactone nanoemulsion (ACR-PCL-NE) for burn wound healing. Nanoemulsion was prepared by using the double emulsion solvent evaporation technique and it was subjected to thermodynamic stability testing, droplet size, polydispersity, zeta potential, pH, and surface morphology analysis. The in vivo study was performed to evaluate the efficacy of nanoemulsion using Sprague-Dawley rats as an animal model. The results of this study revealed that the optimized nanoemulsion was stable and had desirable physicochemical properties. The pH was about 4.02 at 25 °C and the particle size was found to be in the range of 302 ± 4.62 nm while the zeta potential was -7.8 ± 1.22 mV and the polydispersity index of 0.221 ± 0.017. The wound regeneration process was evaluated in vivo by different techniques, the formulation group (FG) showed high wound healing potential as compared to the standard group (SD) and control group (CG). These findings reveal that this nanoemulsion formulation can be used effectively for wound healing. [ABSTRACT FROM AUTHOR]

In the past quarter century, applications of fluorescence resonance energy transfer (FRET) have grown dramatically, and the technology has become an indispensable tool in a wide variety of biological and biophysical domains. It is utilized, in order to acquire information on the conformational changes that occur in single molecules. By utilizing the fluorescence correlation spectroscopy, the pharmaceutical sector has also built huge fluorescence detection systems with extremely small sample sizes, reaching down to the level of single molecules. The fluorescence resonance energy transfer (FRET) between the two dyes, Acriflavine (Acf) and Rhodamine B (RhB), were examined in solution. Energy transfer was observed in fluorescence resonance imaging solutions containing Acriflavine and Rhodamine B with different concentrations of the acceptor RhB dye in the range of (1.5×10-5 M to 3.5×10-5M). Studies using Both UV–Vis absorption and fluorescence spectroscopy demonstrated that the two dyes, when dissolved in solution, appear largely as monomers.

Using TD-DFT/DFT, the ground and excited states of the acriflavine dye were studied in an aqueous medium. The mutual influence of photoexcitation and strong hydrogen bonds with the solvent was studied by comparing the purely implicit and combined modeling of the aqueous environment of the dye. The excitation of acriflavine was calculated considering the vibronic coupling. The effect of photoexcitation on dye vibrations was analyzed. The spatial structure of the acriflavine H-dimer was obtained and its absorption was estimated. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Kufa - Physics is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Display omitted] • Green microwave-synthesized S,N-CQDs have been fabricated from natural sources. • Nitroxynil was assessed by quenching of S,N-CQDs and acriflavine fluorescence. • A comparative study of greenness, whiteness, and blueness was performed. • Successful determination of nitroxynil in various matrices was achieved. The presence of veterinary drug residues in edible animal tissues endangers human health and safety, accordingly, global nations enacted legislative restrictions to monitor their concentrations in food. In this work, we introduce two fluorimetric sensors for determining nitroxynil (NXL), a crucial veterinary medication, in various matrices. Sensor I, novel nitrogen and sulfur-doped carbon quantum dots (S,N-CQDs), was fabricated from strawberry and leek juices as cheap and sustainable natural resources. Only five minutes of microwave radiation were required as a rapid synthesizing technique without any drastic conditions or organic solvents. The S,N-CQDs manifest blue emission using λ ex/em of 340/418 nm. The synthesized nanosensor was characterized using UV Spectroscopy, transmission electron microscopy (TEM), and Fourier-transform infrared spectrometry (FTIR). Sensor II was the acriflavine reagent (AV) that exhibits native fluorescence using λ ex/em of 265/505 nm. Both sensors displayed quantitative turning off in their native fluorescence by increasing concentrations of NXL (1.0–10.0 and 0.5–8.0 µg mL−1) with correlation coefficients r = 0.9998 and 0.9999 for sensors I and II, respectively. The two probes achieved satisfactory percentage recoveries and standard deviation (SD < 4) for NXL assessing in complex matrices of diverse food samples (bovine muscle, kidney, and fat) and Fasciolar® veterinary formulation. Additionally, they have been successfully used to detect the investigated drug in river ecosystems with a mean %recovery of 100.10 ± 1.70, and 99.95 ± 1.31 for sensors I and II, respectively. The two constructed sensors' specificity has been confirmed for all tested matrices reflecting their feasibility as promising platforms in therapeutic drug monitoring, livestock ecosystems, food safety assurance, quality control of drugs, and environmental pollution monitoring. Quenching mechanisms for both methodologies were studied and the reaction stoichiometry for NXL − AV complex was calculated in two ways. Lastly, a comprehensive comparison was performed between the suggested methodologies and published fluorimetric works. The greenness feature was assessed by the Analytical Eco-scale (AES), Green Analytical Procedure Index (GAPI), and Analytical GREEnness Metric Approach (AGREE). In addition, white analytical chemistry principles were checked to assess sustainability criteria using the RGB 12 algorithm. The recently launched Blue Applicability Grade Index (BAGI) metric tool was also employed to assess the practicality (Blueness) character. [ABSTRACT FROM AUTHOR]

Background: Resistance to cisplatin is a major obstacle to effective treatment of bladder cancer (BC). The present study aimed to determine whether a combination of acriflavine (ACF) with cisplatin could potentiate the antitumor property of cisplatin against the BC cells. Furthermore, the molecular mechanism behind the anticancer action of ACF was considered. Methods and results: Two human BC cells (5637 and EJ138) contain mutated form of p53 was culture in standard condition. Cotreatment protocol (simultaneous combination of IC30 value of ACF + various dose of cisplatin for 72 h) and pretreatment protocol (pretreatment with IC15 value of ACF for 24 h + various dose of cisplatin for 48 h) was used to determine the effect of ACF on the cells' sensitivity to main drug cisplatin. To assess the mechanism of action of ACF, real-time PCR was used to evaluate mRNA levels of hypoxia-inducible factor-1α (HIF-1α), Bax, Bcl-2, topoisomerase1 (TOP1) and topoisomerase 2 (TOP2A). Combination of ACF with cisplatin either as cotreatment or opretreatment protocol could significantly reduce the IC50 values of cisplatin as compared to the IC50 of cisplatin when use as a single drug. In addition, ACF could markedly decrease mRNA expression of TOP1 and TOP2A without changing the expression of HIF-1ɑ, Bax and Bcl-2. Conclusions: Our findings indicate that combination of cisplatin with ACF was able to significantly enhance the sensitivity of BC cells to cisplatin. The antitumor activity of ACF is exerted through the downregulation of TOP1 and TOP2A genes expression. ACF may serve as an adjuvant to boost cisplatin-based chemotherapy. [ABSTRACT FROM AUTHOR]

In the present work, a cost-effective Indian jujube seeds derived activated carbon (IJSAC) prepared via o-phosphoric acid chemical activation, is studied for the sequestration of acriflavine (AF) and Victoria blue B (VB) from the aquatic environment. The activated carbon is characterized by Fourier transform infrared spectroscopy, N2-adsorption/desorption isotherm, scanning electron microscopy techniques and point of zero-charge measurement. The specific surface area (SBET) of 571 m2/g with a pore radius of 22.45 Å specifies mesoporous nature of the IJSAC. The implication of operational conditions on the adsorption of both dyes onto IJSAC assessed by batch methodology, establish the optimal conditions as dosage (1.5 and 2.5 g/L), contact time (60 min), pH (8 and 10), and initial concentration (130 and 140 mg/L) for AF and VB uptake, respectively. The Freundlich adsorption isotherm model (R2 = 0.99) appropriates the equilibrium data suggesting multilayer adsorption onto heterogeneous surface sites, while pseudo-second order (R2 = 0.95–0.99) is the best fit kinetic model. The liquid film and intraparticle diffusion modelling demonstrate that the adsorption process of these dyes is governed by both the steps. Maximum Langmuir adsorption capacity is 113.6 mg/g for acriflavine and 92.78 mg/g for Victoria blue B. Thermodynamic studies indicate endothermic and spontaneous adsorption of dyes. The adsorption mechanism for the uptake of AF and VB by IJSAC most probably involves hydrogen bonding, electrostatic and π-π interactions. Based on its high adsorption capacity, relatively faster kinetics, and reusability, IJSAC can be perceived as a proficient and effective adsorbent for cationic dyes removal from the liquid waste.

[Display omitted] Glioblastomas have been historically difficult to treat with poor long-term survival. With novel strategies focused on targeting hypoxia-inducible factor (HIF) regulatory pathways, recent evidence has shown that Acriflavine (ACF) can effectively target glioma invasiveness and recurrence. However, local delivery of ACF and its combinatory effects with Temozolomide (TMZ) and radiation therapy (XRT) have not yet been optimized. In this study we test a novel polymeric matrix that can gradually release ACF at the tumor bed site in combination with systemic TMZ and XRT. In vitro cytotoxicity assays of ACF in combination with TMZ and XRT were performed on rodent and human cell lines with CCK-8 and flow cytometry. In vitro drug release was measured and intracranial safety was assessed in tumor-free animals. Finally, efficacy was assessed in an intracranial gliosarcoma model and combination therapy with TMZ and XRT evaluated. Combination therapy of ACF, TMZ, and XRT was able to reduce cell viability and induce apoptosis in glioma cells. In vitro and in vivo release of ACF was measured in benchtop and animal models. Efficacy was established in an in vivo gliosarcoma model in which intracranial ACF (p < 0.01) significantly improved median survival and the combination therapy of ACF, TMZ and XRT (p < 0.01) significantly improved median survival and led to long-term survival (LTS). We provide evidence that ACF, combined with TMZ and XRT, led to LTS in an intracranial model of rat gliosarcoma. These findings, in combination with the use of a novel polymeric matrix that allows more gradual drug delivery, constitute a first step in the translation of this novel strategy to human use. [ABSTRACT FROM AUTHOR]

To determine the effects of hypoxia-inducible factors (HIF)-1 inhibitors on carbonic anhydrase-IX (CA-IX) enzyme and vascular endothelial growth factor (VEGF) in melanoma. The HIF-1 pathway induces tumor growth and metastasis by stimulating the expression of CA-IX enzyme and VEGF proteins. We evaluated the inhibition effects of Acriflavine and Echinomycin on CA-IX enzyme and VEGF in WM115 (primary) and SKMEL30 (metastatic) cell lines in normoxic and hypoxic conditions with Enzyme Linked Immunosorbent Assay. The cytotoxic activity of HIF-1 inhibitors was performed by using WST-1 assay. All experiments were performed at 450 nm using Epoch™ Microplate Spectrophotometer. IC50 values were observed with a concentration of 3 μmol/L for Echinomycin and Acriflavine in the WST-1 assay. Decreased CA-IX and VEGF levels were determined in both normoxia and hypoxia after inhibitors' treatment with WM115 and SKMEL30 cell lines (p<0.05). Inhibitory effect of HIF-1 inhibitors on CA-IX and VEGF proteins was observed in cell lines WM115 and SKMEL30. Due to the importance of our study, using HIF-1 inhibitors may be an alternative treatment for melanoma. Also to design new HIF-1 inhibitor derivatives is a promising approach for further studies targeting CA-IX enzyme and VEGF. [ABSTRACT FROM AUTHOR]

Acriflavine (ACF) is an antiseptic compound with the potential antitumor activity which is used for the fluorescent staining of RNA due to its dominant fluorescent emission at ∼515 nm. Here, solid lipid nanoparticles (SLNs) containing ACF (ACF-SLNs) were prepared and their physicochemical properties, potential geno/cytotoxicity, as well as the fluorescent properties were investigated. FITC-annexin V/PI staining and cell cycle assays were carried out to find the type of cellular death caused. Particle size analysis and SEM images revealed that spherical ACF-SLNs had a homogeneous dispersion with a mean diameter of 106 ± 5.7 nm. Drug loading (DL) of 31.25 ± 4.21 mg/mL and high encapsulation efficiency (EE%) (89.75 ± 5.44) were found. ACF-SLNs physically were relatively stable in terms of dispersion, size, and EE. The uptake study demonstrated the potential use of fluorescent ACF-SLNs in bio-distribution studies. MTT assay showed that plain ACF could induce growth inhibition of A549 cells with I C 50 of 8.5, 6, and 4.5 μ Mol after 24, 48, and 72 hours, respectively, while ACF-SLNs had stable cytotoxic effects after 48 hours. ACF-SLNs induced remarkable apoptosis and even necrosis after 48 h. Conclusively, ACF-SLNs with acceptable physicochemical features showed increased bioimpacts after 48 h compared to plain ACF. [ABSTRACT FROM AUTHOR]

Using two green and sensitive spectrofluorimetric methods, we quantified two cephalosporins, cefepime (CFM) and cefazolin (CFZ), in raw and pharmaceutical formulations. The first method is based on the reaction between CFM and fluorescamine (borate buffer, pH 8), which yields a highly fluorescent product. After excitation at 384 nm, the fluorescent product emits light at 484 nm. At concentration ranges from 12.0 to 120.0 ng ml−1, the relative fluorescence intensity/concentration curve was linear with a limit of quantification (LOQ) of 2.46 ng ml−1. The second method relied on measuring the CFZ quenching action on acriflavine fluorescence through formation of an ion-associate complex using Britton–Robinson buffer at pH 8. We measured acriflavine fluorescence at 505 nm after excitation at 265 nm. The decrease in acriflavine fluorescence intensity was CFZ concentration-dependent. Using this method, we quantified CFZ in concentrations ranging from 1 to 10 µg ml−1 with a LOQ of 0.48 µg ml−1. We studied and optimized the factors influencing reaction product formation. Moreover, we adapted our methods to the investigation of the mentioned drugs in raw and pharmaceutical formulations with greatly satisfying results. We statistically validated our methods according to International Council on Harmonisation Guidelines. The obtained results were consistent with those obtained with the official high-performance liquid chromatography methods.

Background Probe‐based confocal laser endomicroscopy (pCLE) is a novel, noninvasive technology that provides real‐time lung imaging during bronchoscopy. pCLE shows the elastic fiber network without the use of a fluorescent dye. Elastic fibers produce argon laser‐induced autofluorescence at a wavelength of 488 nm, but tumor cells do not produce autofluorescence at this wavelength. As a result, the tumor cells cannot be observed directly. Therefore, we stained transbronchial biopsy (TBB) specimens with acriflavine to evaluate the benign and malignant structures using pCLE of ex vivo samples and to determine whether rapid histopathological diagnosis of TBB specimens could be made via pCLE. Methods After bronchoscopy, 36 TBB specimens were stained with acriflavine and observed using pCLE. Benign and malignant lesions were classified by cell density and nuclear magnitude disparity. Results We defined the confocal laser endomicroscopic atypia classification from the findings of the cells. The sensitivity for malignancy was 91.3%, and the specificity was 76.9%. Both inter‐observer (κ = 0.48) and intra‐observer (κ = 0.57) agreement confirmed moderate agreement. Conclusion pCLE with acriflavine staining was useful to differentiate malignant from benign TBB specimens, and might be useful as a substitute for rapid on‐site evaluation of histopathological diagnosis.

The present work highlights the broad range of oxygen and nitrogen heterocycles and their applications in medicinal field. A facial approach has been developed for the synthesis of coumarinyl xanthenes and acridine derivatives via one pot multicomponent reaction using green chemical technique. All the isolated compounds were characterized by spectral analysis such as IR NMR and mass. Compounds were screened for their antibacterial and anti-inflammatory activity. While, biological activity results of synthesized coumarin derivatives are quite significant and contribute to the medicinal chemistry. [ABSTRACT FROM AUTHOR]

The synthesis and structural characterization of the monohydrated 1:2 cocrystal salt of acriflavine with 3,5‐dinitrobenzoic acid [systematic name: 3,6‐diamino‐10‐methylacridin‐10‐ium 3,5‐dinitrobenzoate–3,5‐dinitrobenzoic acid–water (1/1/1), C14H14N3+·C7H3N2O6−·C7H4N2O6·H2O] are reported. Single‐crystal X‐ray diffraction measurements show that the title solvated monohydrate salt crystalizes in the monoclinic space group P21 with one acriflavine cation, a 3,5‐dinitrobenzoate anion, a 3,5‐dinitrobenzoic acid molecule and a water molecule in the asymmetric unit. The neutral and anionic forms of 3,5‐dinitrobenzoic acid are linked via O—H...O hydrogen bonds to form a monoanionic dimer. Neighbouring monoanionic dimers of 3,5‐dinitrobenzoic acid are linked by nitro–nitro N—O...N and nitro–acid N—O...π intermolecular interactions to produce a porous organic framework. The acriflavine cations are linked with carboxylic acid molecules directly via amine–carboxy N—H...O, amine–nitro N—H...O and acriflavine–carboxy C—H...O hydrogen bonds, and carboxy–acriflavine C—O...π, nitro–acriflavine N—O...π and acriflavine–nitro π–π interactions, or through the water molecule by amino–water N—H...O and water–carboxy O—H...O hydrogen bonds, and are located in the voids of the porous organic framework. The intermolecular interactions were studied using the CrystalExplorer program to provide information about the interaction energies and the dispersion, electrostatic, polarization and repulsion contributions to the lattice energy. [ABSTRACT FROM AUTHOR]

Some thiazolidinone and tetrazole compounds (7-12),(13-18) were derived from the acriflavine by the synthesis of Schiff bases as intermediate compounds (1-6). Schiff bases compounds were synthesized by reaction the acriflavine with different aldehydes by using microwave method. Thiazolidinone and tetrazole compounds wereprepared by the cyclization of Schiff bases with thioaceticacid to obtain of thiazolidinone compounds (7-12) and with sodium azide to products of tetrazole compounds (13-18). IR, 1H-NMR, and Mass Spectra data have confirmed the structures of synthesized compounds. The synthesized compounds have been screened for their antimicrobial, antifungal, and antioxidant activity. [ABSTRACT FROM AUTHOR]

Nanoparticles are used increasingly for the treatment of different disorders, including burn wounds of the skin, due to their important role in wound healing. In this study, acriflavine-loaded poly (ε-caprolactone) nanoparticles (ACR-PCL-NPs) were prepared using a double-emulsion solvent evaporation method. All the formulations were prepared and optimized by using a Box–Behnken design. Formulations were evaluated for the effect of independent variables, i.e., poly (ε-caprolactone) (PCL) amount (X1), stirring speed of external phase (X2), and polyvinyl alcohol (PVA) concentration (X3), on the formulation-dependent variables (particle size, polydispersity index (PDI), and encapsulation efficiency) of ACR-PCL-NPs. The zeta potential, PDI, particle size, and encapsulation efficiency of optimized ACR-PCL-NPs were found to be −3.98 ± 1.58 mV, 0.270 ± 0.19, 469.2 ± 5.6 nm, and 71.9 ± 5.32%, respectively. The independent variables were found to be in excellent correlation with the dependent variables. The release of acriflavine from optimized ACR-PCL-NPs was in biphasic style with the initial burst release, followed by a slow release for up to 24 h of the in vitro study. Morphological studies of optimized ACR-PCL-NPs revealed the smooth surfaces and spherical shapes of the particles. Thermal and FTIR analyses revealed the drug–polymer compatibility of ACR-PCL-NPs. The drug-treated group showed significant re-epithelialization, as compared to the controlled group.

Acriflavine (ACF) is an antiseptic with anticancer properties, blocking the growth of solid and haematopoietic tumour cells. Moreover, this compound has been also shown to overcome the resistance of cancer cells to chemotherapeutic agents. ACF has been shown to target hypoxia‐inducible factors (HIFs) activity, which are key effectors of hypoxia‐mediated chemoresistance. In this study, we showed that ACF inhibits the growth and survival of chronic myeloid leukaemia (CML) and acute myeloid leukaemia (AML) cell lines in normoxic conditions. We further demonstrated that ACF down‐regulates STAT5 expression in CML and AML cells but activates STAT3 in CML cells in a HIF‐independent manner. In addition, we demonstrated that ACF suppresses the resistance of CML cells to tyrosine kinase inhibitors, such as imatinib. Our data suggest that the dual effect of ACF might be exploited to eradicate de novo or acquired resistance of myeloid leukaemia cells to chemotherapy. [ABSTRACT FROM AUTHOR]

Objectives: Confocal laser endomicroscopy (CLE) is a technology that enables microscopic visualization of lesions in real-time (optical biopsy) and has been successfully applied for clinical use in gastroenterology. Recently, it was also introduced for head and neck squamous cell carcinoma (HNSCC) diagnostics. We previously designed a self-made CLE, which can provide bichrome images, with topical contrast agents that are safe for use in patients. Herein, we report findings of a pilot study using our self-made CLE to image pairs of normal and cancerous tissues. This study aimed to characterize the features of HNSCC compared with normal mucosa and to establish a methodology of in vivo real-time optical biopsy of HNSCCs.Methods: HNSCC tissues were acquired from 10 patients who underwent surgical resection. Dissected specimens were first evaluated for their auto-fluorescence spectral profiles with 473 nm laser excitation and further optical observation. While obtaining the image, auto-fluorescence spectrum and intensity of the reflectance fluorescent signals were measured in real-time by a spectrometer. Subsequently, acriflavine was applied to the specimen to fluorescently label the nuclei and observe the difference between normal and cancerous tissues with 473 nm laser excitation. Finally, double staining with acriflavine and edible Food Red No.106 was performed to observe both nuclei and the cytoplasm of normal and cancerous tissues at 473 nm and 561 nm laser excitation.Results: Lower signals were detected from auto-fluorescence images of cancer tissues than normal tissues with 473 nm laser excitation. After acriflavine application, there was a clear difference between cancer and normal mucosa in the uniformity of nuclear size and shape. In normal mucosa, cells were arranged in an orderly manner, with each cell resembling a frog's egg. By contrast, in cancer tissues, the cell density was higher, and the cellular arrangement was less orderly. Using both acriflavine and Food Red No.106, images became more vivid, but more complicated because red dye staining of the cytoplasm emerged as fluorescence at different wavelengths.Conclusions: Real-time in vivo imaging using the newly developed CLE and conditions may be used to distinguish cancer tissue from normal mucosa without invasive biopsy. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Chemistry & Biotechnology is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article talks about assessment of performance which developed acriflavine thin film composite nanofiltration membrane for seawater treatment and reverse osmosis brine concentration. Topics discussed include the major share of seawater desalination in the state of Kuwait is taken by thermal processes which are multistage flash and multieffect distillation, and thin film composite (TFC) membranes showed a promising way of producing fresh water at low-energy consumption and high purity.

Copyright of Baghdad Science Journal is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Proflavine derivatives are extremely interesting chemotherapeutic agents, which have shown promising pharmaceutical potential due to their wide range of biological activities. This review summarizes the current state of research into the anticancer, antimicrobial, antimalarial and antileishmanial properties of these attractive compounds. Our attention has focused on new classes of proflavine conjugates, which display significant levels of anticancer activity. Highly promising cytotoxic properties have been identified in proflavine conjugates with imidazolidinones, ureas and thioureas. In particular, proflavine‐dialkyldithioureas displayed substantial cytotoxic effect against the human leukemia HL‐60 cells with IC50 values from 7.2 to 34.0 μm. As well, palladium complexes with proflavine ligand have important biologic activity. The LC50 values of these complexes were significantly lower than that of cisplatin against the SK‐BR‐3 cell line. Proflavine derivatives are extremely interesting chemotherapeutic agents, which have shown promising pharmaceutical potential due to their wide range of biological activities. This review summarizes the current state of research into the anticancer, antimicrobial, antimalarial and antileishmanial properties of these attractive compounds. [ABSTRACT FROM AUTHOR]

Hypoxia-inducible factor 1 can sufficiently control the progress of neurological symptoms after ischemic stroke owing to their actions associated with its downstream genes. In this study, we evaluated the role of HIF-1α in attenuating brain damage after endothelin-1 injection. Focal cerebral ischemia in mice were induced by endothelin-1 microinjection. Hypoxia-inducible factor 1 activator, dimethyloxalylglycine (DMOG), and HIF-1α inhibitor, acriflavine (ACF), were used to evaluate the hypoxia-inducible factor 1 activity during cerebral ischemia. The expression levels of HIF-1α, glial fibrillary acidic protein (GFAP), interleukin-10 (IL-10), inducible nitric oxide synthase (iNOS), phosphorylated I-kappa-B-alpha/total I-kappa-B-alpha (p-IκBα/IκBα) and nuclear factor kappa B (NF-kB) were assessed. Besides, mRNA levels of IL-10, tumor necrosis factor- alpha (TNF-α), and NF-kB were also analyzed. Results showed a noticeable increase in hypoxia-inducible factor 1 and IL-10 levels in the DMOG group with a decline in iNOS, TNF-α, and NF-kB levels, implying the anti-inflammatory role of hypoxia-inducible factor 1 activator following stroke. These findings were further corroborated by GFAP immunostaining that showed astrocytic activation to be inhibited 12 days post-ischemia, as well as histological and TEM analyses that demonstrated hypoxia-inducible factor 1 induction to alleviate neuronal soma damage and cell death. Based on our study, HIF-1α could be a potential therapeutic target for ischemic stroke.

Background: Probe‐based confocal laser endomicroscopy (pCLE) is a novel, noninvasive technology that provides real‐time lung imaging during bronchoscopy. pCLE shows the elastic fiber network without the use of a fluorescent dye. Elastic fibers produce argon laser‐induced autofluorescence at a wavelength of 488 nm, but tumor cells do not produce autofluorescence at this wavelength. As a result, the tumor cells cannot be observed directly. Therefore, we stained transbronchial biopsy (TBB) specimens with acriflavine to evaluate the benign and malignant structures using pCLE of ex vivo samples and to determine whether rapid histopathological diagnosis of TBB specimens could be made via pCLE. Methods: After bronchoscopy, 36 TBB specimens were stained with acriflavine and observed using pCLE. Benign and malignant lesions were classified by cell density and nuclear magnitude disparity. Results: We defined the confocal laser endomicroscopic atypia classification from the findings of the cells. The sensitivity for malignancy was 91.3%, and the specificity was 76.9%. Both inter‐observer (κ = 0.48) and intra‐observer (κ = 0.57) agreement confirmed moderate agreement. Conclusion: pCLE with acriflavine staining was useful to differentiate malignant from benign TBB specimens, and might be useful as a substitute for rapid on‐site evaluation of histopathological diagnosis. [ABSTRACT FROM AUTHOR]

A novel thin-film composite (TFC) membrane is prepared by coating titanium dioxide (TiO2) nanoparticle- incorporated acriflavine and trimesoyl chloride (TMC) on polysulfone (PSf) substrate with the aim of enhancing the permeation and salt rejection properties of PSf membrane. The membrane characterization was performed using Fourier transform infrared (FT-IR), atomic force microscope, field emission scanning electron microscope, and contact angle (CA) goniometer. The FT-IR spectral studies confirmed the interfacial polymerization of acriflavine and TMC. The study also confirmed the effective incorporation of TiO2 nanoparticles, and the addition of TiO2 nanoparticle in acriflavine TFC active layer improved the morphology of the membrane and CA. In terms of water flux, the TFC membrane with 0.1 wt.% TiO2 nanoparticle content achieved water flux of 67.1 L m-2h-1 against deionized water and 53 and 44.5 L m-2h-1 against Arabian Gulf seawater and reverse osmosis brine, respectively, when tested using dead-end filtration. The acriflavine TFC membranes showed excellent antifouling characteristics when the loading of TiO2 was 0.1 wt.% with >99% rejection for magnesium (Mg2+), calcium (Ca2+), and sulfate (SO4) ions. Overall, this study demonstrated the potential of using acriflavine as an amine monomer for the fabrication of polyamide layer with increased membrane performance toward seawater pretreatment and brine concentration applications. [ABSTRACT FROM AUTHOR]2-) ions. Overall, this study demonstrated the potential of using acriflavine as an amine monomer for the fabrication of polyamide layer with increased membrane performance toward seawater pretreatment and brine concentration applications. [ABSTRACT FROM AUTHOR]

An easily performed, specific, sensitive, rapid, reliable and inexpensive procedure for the spectrofluorometric quantitation of ascorbic acid was proposed using acriflavine as a fluorescence quenching reagent. The procedure was based on the determined quenching effect of ascorbic acid on the natural fluorescence signal of acriflavine and the reaction between ascorbic acid and acriflavine in Britton–Robinson buffer solution (pH 6) to produce an ion‐associated complex. The reduction in acriflavine fluorescence intensity was detected at 505 nm, while excitation occurred at 265 nm. The relationship between quenching fluorescence intensity (∆F) and concentration of ascorbic acid was linear (R2 = 0.9967) within the range 2–10 μg/ml and with a detection limit of 0.08 μg/ml. No significant interference was detected from other materials often found in pharmaceutical nutritional tablets. The obtained results were compared with those from high‐performance liquid chromatography and appeared in good agreement, with no important differences in precision or accuracy. The proposed spectrofluorimetric method was used to determine the amount of ascorbic acid in a number of commercial pharmaceutical nutritional supplement tablets with a 95% confidence performance. [ABSTRACT FROM AUTHOR]

Abstract The fluorescence quenching of Acriflavine (AFN) by certain estrogens was examined in aqueous media by employing steady state and time-resolved fluorescence measurements. The absorption spectra of AFN change with significant bathochromic shift in presence of quencher molecules. The quenching behavior was examined by correlating the bimolecular quenching rate constant (k q) with the free energy change (ΔG). The decrease in quenching rate constant depends on the increase in oxidation potential of quencher molecules. The fluorescence quenching experiments were carried out in different solvents of varying polarities and reveals the possibility of charge transfer quenching mechanism. Lifetime measurements indicate static quenching. The quenching behavior is addressed from bond dissociation enthalpy (BDE) calculations. The antioxidant activity of estrogen compounds were evaluated by deoxyribose oxidation assay. Graphical Abstract Unlabelled Image Highlights • Fluorescence quenching of acriflavine with estrogens were studied. • Lifetime measurements indicate static quenching. • Thermodynamic parameters point out the hydrogen bonding interaction. • Bond dissociation enthalpy was calculated for all estrogens. • Deoxyribose oxidation assay was carried out to check the antioxidant activity. [ABSTRACT FROM AUTHOR]

Introduction: Diabetic foot and complicated ulcers are relatively common occurrence in daily surgical to patient department for managing them various dressing materials and solutions are available. One of such is acriflavine emulsion. Case Presentation: Both patients were diabetic having large ulcers over leg 2nd was Hepatitis B positive also having large leg ulcer due to insect bite. In both Acriflavine emulsion was used as dressing material. STSG was performed in both and graft were accepted with uneventful post op course Discussion: Acriflavine made from acridine has a local antiseptic property with Antimicrobial and antiviral action it does have a skin irritant 1 property but to neutralise that glycerine was used in 1:1000 emulsion Conclusion: Acriflavine which was used in world war1 as antiseptic solution for war wounds can be used for dressing of complicated ulcers and wounds to gainbetter results. [ABSTRACT FROM AUTHOR]

A comprehensive study was conducted on the adsorption, corrosion inhibition efficiency and stability of acriflavine (ACF) on mild steel (MS) in 1 M HCl solution. Electrochemical studies were conducted to determine the corrosion protection ability of the inhibitor after short and long immersion times. The MS surface after exposing to the uninhibited and inhibited solutions were characterized by SEM, EDX, AFM and contact angle measurements. The excess surface charge of the metal and some thermodynamic parameters were derived after 1 h and 6 h exposure times and a possible adsorption and inhibition mechanism was discussed. The electrochemical stability of the inhibitor film formed on the metal surface was studied using potentiodynamic and potentiostatic techniques. It was found that ACF adsorbs on the MS surface via dominantly chemical and weakly physical interactions and forms a protective surface film. The film was adherent, uniform, protective and electrochemically stable. The inhibitor film provides maximum inhibition efficiencies of 92.8% and 97.1% at 1 mM after 1 h and 6 h immersion times. ACF mitigates the rates of both anodic metal dissolution and cathodic hydrogen evolution reactions. The excess surface charge of the steel in the inhibited solution was negative, which becomes more evident after longer exposure time. [Display omitted] • Adsorption and corrosion protection ability of acriflavine on mild steel was studied in 1 M HCl solution. • Acriflavine forms an adherent, uniform, very protective and stable film on mild steel. • The inhibitor mitigates the rates of anodic metal dissolution and cathodic hydrogen evolution reactions. • The excess surface charge of the steel in the inhibited solution was negative. • The inhibitor provides inhibition efficiencies of 92.8% and 97.1% after 1 h and 6 h. [ABSTRACT FROM AUTHOR]

Abstract Background: A small percent of patients with colorectal cancer (CRC) respond to 5-Fluorouracil (5-FU), as a first line of chemotherapy. In this study in, in order to design a new chemotherapy protocol, the effect of 5-FU and acriflavine (ACF) cotreatment on mortality rate of CRC cell lines was investigated. Materials and Methods: Cytotoxicity of 5-FU and ACF against CRC cell lines (LS174T, SW480 and HCT116) was detected using MTT assay. Cells were treated with different concentrations of 5-FU (0.5-64 µM) or ACF (0.07-5 µM) for 72 hours and then cell viability and drugs IC50 was calculated. To assess the effect of ACF on anticancer activity of 5-FU, cells were cotreated with different concentrations of 5-FU and IC30 concentration of ACF. Results: ACF and 5-FU suppress the viability of CRC cell lines in dose-dependent manner. 5-FU and ACF have most cytotoxic effect on LS174T and the lowest cytotoxic effect on SW480 cells. Cotreatment of ACF with 5-FU could not significantly change the sensitivity of cells against 5-FU (p>0.05). Conclusion: In this study, the fatal and cytotoxic effect of ACF on three CRC cell lines was shown. However, cotreatment of ACF with 5-FU could not improve the anticancer activity of 5-FU.

Introduction: There is still a debate for the link between obstructive sleep apnoea (OSA) and cancer. The mechanisms underlying this causality are poorly understood. Several miRNAs are involved in cancer development and progression with expression being influenced by hypoxia. The aims of this work were (i) to compare miRNAs expression in controls versus patients affected by OSA without or with cancer (ONCO-OSA) and (ii) in colorectal cancer cells exposed to intermittent hypoxia (IH), to evaluate miRNAs impact on tumor progression in vitro., Methods: We detected miRNAs by qRT-PCR in patients' sera and in CaCo2 cells exposed to 2-32h of IH with or without acriflavine (ACF), a HIF-1 inhibitor. Viability and transwell invasion test were applied to investigate the proliferation and migration of CaCo2 exposed to IH and treated with miRNA inhibitors or acriflavine. HIF-1α activity was evaluated in CaCo2 cells after IH., Results: The levels of miR-21, miR-26a and miR-210 increased in OSA and ONCO-OSA patients compared to controls. MiR-23b increased in ONCO-OSA patients, and miR-27b and miR-145 increased in OSA but not ONCO-OSA patients. MiR-21, miR-26a, miR-23b and miR-210 increased in cells after IH. IH stimulated cell proliferation and migration. This effect was reduced after either miRNA inhibition or acriflavine treatment. MiRNA inhibition reduces HIF-1α gene expression. Conversely, acriflavine reduced the expression of these miRNAs., Conclusions: We identified a signature of miRNAs, induced by the IH environment. They could be implicated in cancer development and progression through a regulatory loop involving HIF-1., (Copyright © 2023 The Author(s). Published by Elsevier España, S.L.U. All rights reserved.)

Graphical abstract Abstract Acriflavine (ACF) hydrochloride is currently repurposed as multimodal drug, inhibiting hypoxia-inducible factors (HIF) pathways and exerting cytotoxic properties. The aim of this study was to encapsulate ACF in reverse micelles and to incorporate this suspension in lipid nanocapsules (LNC). Designs of experiments were used to work under quality by design conditions. LNC were formulated using a phase-inversion temperature method, leading to an encapsulation efficiency around 80%. In vitro , the encapsulated drug presented similar cytotoxic activity and decrease in HIF activity in 4T1 cells compared to the free drug. In vivo , ACF-loaded nanoparticles (ACF dose of 5 mg/kg) demonstrated a higher antitumor efficacy compared to free ACF on an orthotopic model of murine breast cancer (4T1 cells). Moreover, the use of LNC allowed to drastically decrease the number of administrations compared to the free drug (2 versus 12 injections), suppressing the ACF-induced toxicity. [ABSTRACT FROM AUTHOR]