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A Schiff base and triazolophthalazine derivatives of hydralazine: Crystal structures, DNA binding properties and DFT studies
No full textIn this study, pharmacologically active hydralazine-hydrazone compounds, a new hydralazine-hydrazone compound (KMe) and its hydrochloride salt (KMeS) and cyclic analog triazopthalazine (KMeB) were prepared and their structures were characterized by spectral and analytical methods. Crystal structures of compounds KMeB and KMeS were determined by single crystal X-ray crystallography. DNA binding properties of the compounds were studied by UV–Vis absorption, photoluminescence and viscosity studies. Molecular dockings were performed in order to investigate the binding interactions of the compounds with DNA. Related molecules were optimized at B3LYP/6–311G(d) level in water. In this stage, the Polarizable Continuum Model (PCM) using the integral equation formalism variant (IEF-PCM) model is used solvation model. Electronic properties of these compounds are investigated by calculation of contour diagram of molecular orbitals (MOs), molecular electrostatic potential (MEP) maps, Hirshfeld surface analyses and determination of molecular electronic mobility. Additionally, molecular docking analyses of this compounds are done against DNA structure which PDB ID is 1BNA. Finally, molecular mechanics with generalised Born and surface area solvation (MM/GBSA) analyses of complex structure is done. The DNA-binding properties of the synthesized compounds (KMe, KMeB, and KMeS) were systematically investigated via UV–Vis spectroscopic titration experiments. Compared to ethidium bromide, a standard DNA intercalator with a Kb value of 1.23 ± 0.07 × 10⁵ M⁻¹, the compounds KMe, KMeB, and KMeS exhibit markedly higher binding constants
Synthesis, structural characterization, and biological evaluation of cinnamaldehyde–azomethine hybrids: In Vitro and In Silico approaches
No full textWe herein reported the synthesis and investigation of biologically active novel compounds, which integrate cinnamaldehydes and azomethine moieties into one molecule. Seven cinnamaldehyde-based azomethines with polyamine backbones were synthesized by condensation reaction in a non-catalyst medium, and their structures were studied by NMR, FTIR, mass and elemental analysis. Antibacterial activity was investigated against Gram-positive and Gram-negative bacterial strains by a two-fold microdilution method, and results were compared with the known antibiotics. The obtained results revealed that compound 5 exhibited promising activity against a clinical isolate of S. aureus, with a MIC value of 0.016 μmol/mL (8 μg/mL); therefore, due to its lowest MIC, the time-kill kinetics and growth inhibitory effects were further evaluated at 2× MIC to assess its bactericidal potential. Cytotoxicity studies demonstrated that compound 5 exhibited minimal toxicity toward human keratinocyte cells, indicating low overall cytotoxicity on mammalian cells. To study the mechanism of action of compound 5, the effect of the investigated molecule on the ultrastructural organization of S. aureus was studied by using transmission electron microscopy, which showed that the investigated sample directly affects the process of bacterial replication by revealing nucleoid enlightenment, remnants of destructively altered fragments of the cell septum, disruption of cell wall structure. To elucidate the antibacterial mechanism of the targeted compound, molecular docking identified target proteins 3VSL and 5M18 with their catalytic and allosteric sites, and 100 ns MD simulations (RMSD, Rg, SASA, RMSF) confirmed the synthesized ligand's stable binding and interaction with these proteins
SINIF ÖĞRETMENLERİNİN PROGRAM UYARLAMA ÖRÜNTÜLERİ İLE PROGRAM OKURYAZARLIKLARI VE PEDAGOJİK TASARIM KAPASİTELERİ ARASINDAKİ İLİŞKİNİN İNCELENMESİ
No full textEffect of surfactant-modified bulk micro-nanobubbles on quartz aggregation and particle-bubble attachment in flotation
No full textBulk micro-nanobubbles (BMNBs) play a crucial role in regulating particle-bubble interactions during flotation; however, the influence of different surfactants on BMNB properties and their underlying mechanisms in fine mineral flotation remains unclear. To address this gap, this study systematically investigated the effects of BMNBs generated with different surfactant types and concentrations on quartz flotation performance, particle aggregation characteristics, and particle-bubble attachment dynamics. Flotation tests, in-situ particle size distribution (PSD) analyses, and three-phase contact line (TPCL) measurements revealed that increasing surfactant concentration led to higher BMNB numbers, size adjustment, and improved stability, thereby significantly enhancing quartz aggregation and bubble attachment, ultimately improving flotation recovery. Among the tested surfactants, ionic surfactant-derived BMNBs (e.g., cetyltrimethylammonium, CTAB) exhibited a stronger promotion of particle-bubble attachment and floc formation compared to nonionic polyethylene glycol 400 (PEG400), while sodium oleate (NaOl)-derived BMNBs, despite their increased number, exhibited stronger negative charge, which enhanced electrostatic repulsion between particles and bubbles, limiting attachment efficiency. TPCL results further showed that with increasing surfactant concentration, the liquid film drainage and rupture processes were hindered by enhanced Marangoni effects and interfacial potentials, delaying TPCL formation. Nevertheless, in flotation systems, the synergistic action of collectors and BMNBs substantially increased particle-bubble collision frequency and aggregation efficiency, resulting in continuous improvement of flotation performance. Overall, surfactant type and concentration govern the number, size, and interfacial properties of BMNBs, which in turn control the formation and structure of bubble flocs, thereby dominating quartz aggregation and attachment kinetics. This study elucidates the mechanisms of BMNBs in mineral flotation and provides theoretical and practical insights into optimizing BMNB-assisted fine particle flotation
Development of pyridazinone derivatives linked ethyl-bridged-1,2,4-triazole for potential cancer therapy
No full textA series of novel pyridazinone derivatives linked ethyl-bridged-1,2,4-triazole were synthesized starting from p-chloroacetophenone. The chemical structures of the compounds 5(a-f) were identified by 1HNMR, 13CNMR and LC-QTOF-MS analysis. In this study, the DDPH method was used to evaluate the antioxidant properties of the compounds. The anticancer activity of the compounds was investigated by MTT method in MCF-7, MDA-MB-231 and L929 cell lines. Gene expression levels of Bcl2, Bax and Casp9 genes were compared, and stages of cell death were determined with high accuracy by flow cytometry. Since compound 5a showed promising cytotoxic effects, molecular docking study was performed to support these results and binding values against Bcl2 anti-apoptotic (PDB ID: 6QGG), Bcl-2 (PDB ID: 4IEH) and tubulin regulation (PDB ID: 1SA0) targets were calculated
MULTI-CRITERIA PERFORMANCE ASSESSMENT OF BEVERAGE COMPANIES INTEGRATING FINANCIAL AND ESG INDICATORS: A HYBRID ANALYTICAL FRAMEWORK
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Novel AS1411-gallium(III) phthalocyanine conjugates for targeted photodynamic therapy
No full textIn this study, peripheral tetra, non-peripheral tetra and peripheral octa gallium (III) phthalocyanines bearing 4-mercaptopyridin groups (Pc1, Pc2 and Pc3) and the quaternized derivatives (Pc1Q, Pc2Q and Pc3Q) of these compounds were synthesized. The structures of all compounds were confirmed by UV–Vis., FT-IR, 1H NMR, MALDI-TOF mass spectra and elemental analysis. The interaction of Pc1Q, Pc2Q and Pc3Q with AS1411 aptamer was investigated by UV–Vis. and CD spectroscopies. The binding constants and interaction stoichiometry values were found spectrophotometrically. The effects of the compounds on AS1411 structure were determined by CD spectroscopy. The stability of AS1411-Pc conjugates was investigated by 1-month long CD spectroscopic monitoring. The interaction of Pc1Q, Pc2Q and Pc3Q with AS1411 was also examined through electrochemical impedance spectroscopy (EIS) technique. The impact of doxorubicin (Dox) on the binding affinity of each phthalocyanine to AS1411 was examined to validate the specificity of our assay within complex biological environments. The cytotoxic activities of AS1411, individual phthalocyanines and AS1411-Pc complexes were also studied in both MCF-7 and Dox-Res-MCF-7 cell lines in the presence and absence of Dox. The findings suggest that phthalocyanines conjugated with aptamers, particularly Pc2Q, enhance apoptosis and cytotoxicity, making them promising candidates for selective cancer treatment
Bioremoval of crystal violet dye from aqueous solutions using Physalis Peruviana calyx: mechanism, biosorption isotherms, kinetic modeling, and thermodynamic analysis
No full textThe first reported Crimean–Congo hemorrhagic fever reinfection in the literature: 11 years apart
No full textCrimean-Congo Hemorrhagic Fever (CCHF) is a viral zoonosis endemic to several regions, including Türkiye. Although it is generally assumed that CCHFV infection confers long-lasting immunity, the durability and mechanisms of this protection remain unclear. Here, we report the first PCR-confirmed reinfection case of CCHFV, occurring 11 years after the initial episode, in a patient from the hyperendemic region of Sivas, Turkiye. The second episode presented with milder symptoms and no hemorrhagic findings, suggesting a degree of partial immune protection. This case challenges existing assumptions about lifelong immunity to CCHFV and highlights the need for further studies on reinfection dynamics and immune memory in endemic settings