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The solid charge transfer (CT) complexes of fluorescein (Flu) with definite acceptors (tetrafluoro para benzoquinone (Fla); 7,7,8,8-tetracyanoquinodimethane (TCNQ); 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) and iodine) were prepared. Several characteristic analytic procedures such as transmission (FT-IR), diffuse reflectance, UV-Vis absorption, and cyclic voltammetry were used to determine the structural and optical properties of the prepared fluorescein charge transfer complex. Kubelka Munk model (K-M) and the absorption spectral fitting (ASF) methods were used to obtain the optical transitions of the solid fluorescein charge transfer complex and fluorescein CT complexes in methanol solution. The cyclic voltammetry method has been presented as capable of obtaining valuable information on quasi-reversible redox systems in the fluorescein CT-complexes. The electrochemical gap of the fluorescein CT complex was successfully determined from the cyclic voltammetry technique. Theoretical calculations (density functional theory) were made to corroborate experimental results for the synthesized CT complexes. KEY WORDS: Fluorescein charge transfer complex, Optical spectroscopy, Cyclic voltammetry Bull. Chem. Soc. Ethiop. 2023, 37(2), 515-532. DOI: https://dx.doi.org/10.4314/bcse.v37i2.19

Although many material designs or strategic methods have been proposed for treating oil spills and oily wastewater, the complex oily state, dealing with the harsh operating conditions of oil–water separation (such as the recovery of viscous spilled crude oil, bacteria-containing oily wastewater, and removal of spilled oil under fire), and the autorecycling of oil and absorption materials remain a great challenge. This work proposed an ingenious design strategy of “several birds with one stone” to prepare pH/thermoresponsive flame-retardant/photothermal bactericidal P-Fe3O4-polydopamine (PDA)@melamine–formaldehyde (MF) foams. This design makes the foams remarkably effective in the recovery of spilled viscous crude oil as well as in the separation of bacteria-containing oily emulsions, particularly for instant fire extinguishing by magnetically controlled oil absorption as well as for fire alarms. The photothermal effect and pH response induce a change in the surface wettability of the foams, facilitating excellent autoadsorption/desorption of the spilled oil. The photothermal bactericidal activity and fouling resistance of the foam are beneficial to the separation of bacteria-containing oily wastewater. Outstanding flame-retardant properties and maneuverable magnetic control enable the foam to rapidly recover the spilled oil in a large range of fires, extinguish fires instantly, and facilitate early fire warning. The proposed strategy is expected to inspire further research on treating oil spills under complex conditions.

Background: Due to the emergence of resistance to available anticancer agents, the demand for new cytotoxic agents has grown. Objective: This study aims at synthesis and cytotoxic evaluation of new acrylic acid derivatives bearing quinolinone and halogenated quinolinone derivatives against three cancer cell lines. Methods: New acrylic acid derivatives bearing quinolinone and halogenated quinolinone moieties were synthesized and screened for their cytotoxic activity against breast MCF-7, liver HepG2, and colon HCT-116 cancer cell lines. Results: Molecules 3 and 8 showed the most potent cytotoxic activity against HCT-116. DNA flow cytometry assay showed cell cycle arrest at the G1 phase and cellular apoptosis. Moreover, molecules 3 and 8 showed cyclin-dependent kinase 2 (CDK2) inhibitory activity compared to the untreated control sample. Conclusion: Acrylic acid derivatives bearing quinolinone and halogenated quinolinone moieties represent an important core and could be used as a lead for further development of drug compounds in order to achieve promising therapeutic results.

International audience; A zinc(II) complex of polypyazole containing ligand namely, [Tp*ZnCl] (Zn1) {Tp* = tris(3,5-dimethylpyrazolyl)borate}, along with its zinc(II) bound hydroxo complex [Tp*Zn–OH] (Zn2) were synthesized and characterized by FT-IR, Raman, 1H NMR techniques and elemental analysis. In alkaline solution (0.1 M KOH), the Zn2 modified glassy carbon (GC), namely GC–Zn2, was investigated as a molecular electrocatalyst for the hydrogen evolution reaction (HER). Different quantities (ca. 0.1–0.5 mg cm–2) of Zn2 were loaded on GC electrodes to make various GC–Zn2 electrodes. These electrodes were utilized as cathodes in 0.1 M KOH to produce H2 using linear sweep voltammetry (LSV) measurements. The HER electrocatalytic activity of the GC–Zn2 catalyst was found to be quite high and it increased with the catalyst loading density. The top performing electrocatalyst, GC–Zn2 (0.5 mg cm–2), demonstrated considerable HER catalytic performance with a low HER onset potential (EHER) of –33 mV vs. RHE and a high exchange current density of 0.59 mA cm–2. Moreover, the top performing electrocatalyst had a Tafel slope of –152 mV dec–1 and consumed an overpotential of 135 mV to generate a current density of 10 mA cm–2. Under the same operating conditions, these HER electrochemical kinetic parameters were found to be not remarkably far from those determined for commercial Pt/C (–10 mV vs. RHE, 0.88 mA cm–2, 108 mV dec–1 and 110 mV to yield a current density of 10 mA cm–2). In addition, the most active molecular electro-catalysts for H2 production from aqueous alkaline electrolytes were found to be comparable to the HER electrochemical kinetic parameters reported here for the GC–Zn2 electrocatalyst. Using 5000 cycles of repetitive cyclic voltammetry and 48 h of chronoamperometry measurements, the best electrocatalyst’s stability and long term durability were tested. It exhibited high stability for the HER catalytic activity.

The microwave irradiation approach was adapted to prepare bismuth doped Cadmium Oxide nanostructures with varied Bi doping levels (1%, 3%, and 5%). Analytical research was conducted on the impact of Bi doping on the structure, crystallite size, shape, band gap, and antimicrobial behavior of CdO nanostructures. All materials developed polycrystalline and cubic structures with (111), (200), and (311) orientations, according to X-ray diffraction spectra. Particles are homogeneously distributed in SEM pictures, and Bi doping has an effect on the morphology. Additionally, as the level of Bi-doping is increased, grain size reduces from 40 to 20 nm. The TEM micrographs revealed agglomerated spherical shaped particles. With increasing amounts of Bi doping in the CdO nanostructures, the shapes and distribution of particles changed. With increasing Bi doping concentration, the energy band gap shifted from 1.94 to 2.2 eV. The antibacterial activity of pure and Bi doped CdO nanoparticles was tested using the Plate count method. CdO and Bi-CdO nanoparticles were investigated for their size-dependent antibacterial efficacy against G. negative and G. positive microorganisms. 5% of Bi doping level combined with a smaller particle size results in a toxicity of 89% for G. negative pathogens and 78% for G. positive pathogens.

Surfactant based microwave irradiated and alkaline medium involving wet chemical method was adopted to prepare CdO nanostructures. The phase evaluation of prepared and annealed CdO nanostrucutures has been analyzed by XRD and FTIR. The average size of the crystallite was estimated to be 54 nm for the NH4OH reagent and 60 nm for the NaOH reagent in the assisted synthesis. Specific surface area, lattice parameter, X-ray density, dislocation density, microstrain, texture coefficient and Williamson Hall have been calculated from the XRD profile. UV transmittance and the K-M plot of DRS and PL spectra were used to examine the optical properties of CdO nanostructures. The spherical and rod-like structures of CdO prepared with strong and weak alkaline medium have been recorded through SEM and TEM micrographs. The four-step process of hydration, intermediate formation, metal hydroxide formation, and metal oxide formation confirms that the experiment in the presence of 0.1 M sodium hydroxide results in rod-shaped nanostructures.

The reaction of the tridentate ligand bis(2-picolyl)amine (BPA) with the chloride or perchlorate salts of zinc(II) ions yielded two zinc(II) complexes of the types: [(BPA)ZnCl2]·2H2O (1) and [(BPA)2Zn](ClO4)2 (2). The intermediate complex species, namely [(BPA)Zn(OH)(H2O)](ClO4) (3) and [(BPA)Zn-OP(= S)(CH3)2] (4) were successfully isolated separately in good yields and pure forms. Complexes 1–4 were characterized in the solid state by using elemental analyses, thermal analyses, FT-IR, and X-ray single crystal diffraction as well as in solution by using 1H NMR titration and cyclic voltammetry (CV). From X-ray structural and spectral features it can be concluded that the coordination environment around Zn(II) ion in 1 is a distorted square pyramidal geometry with τ5 value of 0.148. Whereas in 2, two picolyl chelates in the equatorial plane and two slightly longer axial pyridines are coordinated in a distorted octahedral trans-facial arrangement. Kinetic studies were performed on these complexes to evaluate their efficiency as functional hydrolase models for the hydrolysis of the toxic organophosphate insecticide, Fenitrothion. The pH-dependence of the catalytic rate gives a bell-shaped curve, which gives a strong proof that the hydroxoaqua complex [(BPA)Zn(H2O)(OH)]− 3 is the catalytically active species in the hydrolysis reactions than that of the octahedral [(BPA)2Zn]2+ with fully saturated coordination sphere.

The Ni-Nb2O5 nanocatalysts have been prepared by the sol–gel method, and the catalytic hydrodeoxygenation (HDO) performance of anisole as model compound is studied. The results show that Nb exists as amorphous Nb2O5 species, which can promote Ni dispersion. The addition of Nb2O5 increases the acidity of the catalyst. However, when the content of niobium is high, there is an inactive Nb-Ni-O mixed phase. The size and morphology of Ni grains in catalysts are different due to the difference of Nb/Ni molar ratio. The Ni0.9Nb0.1 sample has the largest surface area of 170.8 m2·g−1 among the catalysts prepared in different Nb/Ni molar ratios, which is mainly composed of spherical nanoparticles and crack pores. The HDO of anisole follows the reaction route of the hydrogenation HYD route. The Ni0.9Nb0.1 catalyst displayed a higher HDO performance for anisole than Ni catalyst. The selectivity to cyclohexane over the Ni0.9Nb0.1 sample is about 10 times that of Ni catalyst at 220 °C and 3 MPa H2. The selectivity of cyclohexane is increased with the increase of reaction temperature. The anisole is almost completely transformed into cyclohexane at 240 °C, 3 MPa H2 and 4 h.

In recent years, because of their excellent electrocatalytic action and applications in different fields, metal oxide nanostructures have received massive consideration from scientists. Zinc oxide nanostructures are useful materials for a range of sensing applications and possess admirable electrocatalytic properties and stability. The current research presents the natural citric acid assisted synthesis of ZnO nanostructures and their structural, optical, morphological and thermal properties. X-ray diffraction was studied for the phase assessment of as prepared (Z1) and annealed ZnO (Z2) nanostructures and the crystallite sizes of the Z1 and Z2 samples were also located in the range between 35 nm and 38 nm. FESEM and TEM experiments were carried out to explore the surface features of Z1 and Z2 samples. The polycrystalline existence of the samples is demonstrated by the hexagonal, cubic and spherical shaped ZnO nanostructures. The energy band gap of Z1 and Z2 samples was determined (3.16 eV for Z1 and 3.12 eV for Z2) from the UV spectrum. The impact of annealing treatment on the thermal stability of ZnO nanostructures was studied and the main peak was observed for the Z1 sample at ~249 °C and for the Z2 sample at ~289 °C.

The Sol–Gel approach is used to synthesize samarium-doped TiO2 nanoparticles (Sm- TiO2 NPs). Research on the structural, morphological and optical properties of TiO2 nanoparticles by XRD, FESEM, TEM, UV, FTIR, and PL was used. The Sm-TiO2 NPs are verified by the XRD profile of anatase, brookite and rutile phase structures. Crystallite size decreases when Sm doped with TiO2 nanoparticles. The external morphologies of the TiO2 nanoparticles in spherically shaped Sm are captured by FESEM. The sample size distribution and polycrystalline composition of the particles have been analyzed using TEM. The EDX spectrum verifies the presence of Ti, O and Sm elements of all the samples. The values have been found to be very close to what has been expected. Sm substitution greatly affected the optical bandgap of TiO2 nanoparticles. It shows that the band gap decreases from 3.64 to 3.61 eV as the concentrations of Sm increases. FTIR confirms the presence of functional groups and Ti–O bonds present in the prepared sample. PL analysis shows the emission for violet range. Using the dip-coating process, a thin film for sensor function is developed. PVDF flat sheet membrane is used as a substrate for sensing material. For various ethanol concentrations with optimized operating temperatures of 303 K, the sensing behaviour of the sensor element is investigated. The very rapid reaction and recovery time of 10 s and 8 s shows that the prepared samples are appropriate for gas sensor applications.

Recent advancements in biorefinery processes necessitate search for cost effective and thermostable cellulases. This study was designed to characterize the cellulase obtained from a thermophilic bacterium, Neobacillus sedimentimangrovi UE25. A combined pretreatment of NaOH and methyltrioctylammonium chloride was given to sugarcane bagasse (SB) for lignin removal and the pretreated SB was utilized as a carbon source for the cellulase production. The thermostable cellulase thus obtained was characterized by adopting central composite design which has not been reported earlier for this purpose. Cellulase showed its maximum activity at pH 7 and temperature 60 ℃ and it remained active in the presence of many salts and detergents. Endoglucanase (EG) was found to be stable for 30 min at 80 ℃. The purification of EG by using DEAE column yielded specific activity and purification fold of 365.866 IU mg

International audience; The ligand potassium hydrotris(N- (2,6-xylyl)-2-thioimidazolyl)borate (KTtxylyl) was utilized to construct a carbon paste modified electrode (KTtxylyl/CPE), which was studied using electrochemical impedance spectroscopy, cyclic voltammetry and square wave voltammetry (SWV). Its electrochemical response was investigated, and it demonstrated a significant improvement in the detection of both lead(II) and cadmium(II), allowing determination of lead(II) at trace concentrations. The spectroscopic evidence includes FT-IR, Raman, 1H NMR and also DFT calculations using B3LYP/LANL2DZ level of theory indicate the high affinities of these ions toward the ligand forming lead(II) and cadmium complexes of the type [TtxylylMCl]. Negative electrostatic potential of the tri(thione) donors deriving their binding abilities toward both ions. The detection limits based on 3(SD/m) were; 0.112 μM and 0.204 μM for lead(II) and cadmium(II), respectively. The simultaneous detection of these ions in several waste water samples was examined in order to verify the modified electrode. Data from the ICP-AES instrument was compared to the results obtained.

The present work-study the improvement of the loading and release efficiency of sofosbuvir drug (SOF) for anti-hepatitis C virus (HCV) by the combination process with β-cyclodextrin (βCD) basket to form a novel self-assembly βCD-SOF which load on the chitosan nanoparticle (Cs NPs) to form a novel hybrid composite (Cs@βCD-SOF). The characterization process performs for confirming the formation of hybrid composite with various methods. The loading efficiency of SOF is performed by UV-Vis spectroscopy, which is reported at 94.54% for Cs@βCD-SOF, while in the reverse case the efficiency is βCD-SOF@Cs 65.2%. The binding constant (K

Simple preparation of flame-retardant, photoluminescent, and superhydrophobic smart nanocomposite coating was developed and applied onto cotton fibres using the simple pad-dry-cure technique. This novel strategy involved the immobilization of rare-earth-doped aluminium strontium oxide (ASO; SrAl2 O4 :Eu+2 ,Dy+3 ) nanoparticles, environmentally friendly room temperature vulcanizing silicone rubber (RTV) and environmentally friendly Exolet AP422 (Ex). The fabrics were also able to produce a char film in the fire-resistant assessment, providing fibres with a self-extinguishing characteristic. Furthermore, the fire-retardant performance of the coated cotton samples remained resistant to washing over 35 laundry cycles. The superhydrophobicity of the treated fabrics was monitored to improve by increasing the photoluminescent phosphor nanoparticles. The produced transparent photoluminescent film displayed an absorption at 360 nm and an emission at 526 nm. The photoluminescent fabrics were observed to generate different colorimetric shades, including white, green-yellow and bright white as monitored by Commission Internationale de l'Eclairage laboratory colorimetric coordinates. Slow emissions were detected for the treated cotton fabrics as monitored by emission, ultraviolet-visible light absorption, lifetime, and decay time spectral profiles to indicate glow in the dark phosphorescence effect. Both comfort and mechanical properties of the coated fibres were evaluated by measuring their bending length and air permeability.

In this study, the role of iron sulfide (FeS) content on the structural and optical properties of graphene/polyvinyl alcohol (Gr/PVA) blend has been examined for environmental-friendly applications. Gr/PVA blend filled with FeS (0 to 10 wt%) were equipped using the casting technique. The prepared samples were studied via a scanning electron microscope, X-ray diffractometer, FT-IR and UV–visible-NIR spectrophotometers. XRD analysis shows that the crystallinity increases with increasing FeS concentration in the host Gr/PVA blend. UV–visible-NIR analysis shows that the direct optical bandgap of composite blends shrinks from 5.37 to 4.68 eV as FeS content is increased to 10 wt%. Also, it confirms that the refractive index and optical conductivity of Gr/PVA blend could be significantly enhanced via FeS filling. FeS filled Gr/PVA blends are recommended eco-friendly applications.

The agricultural use of organophosphorus pesticides is a widespread practice with significant advantages in crop health and product yield. An undesirable consequence is the contamination of soil and groundwater by these neurotoxins resulting from over application and run-off. Here, we design and synthesize the mononuclear zinc(II) complexes, namely, [Zn(AMB)2Cl](ClO4) 1 and [Zn(AMB)2(OH)](ClO4) 2 (AMB = 2-aminomethylbenzimidazole), as artificial catalysts inspired by phosphotriesterase (PTE) for the hydrolysis of organophosphorus compounds (OPs) and simultaneously detect the organophosphate pesticides such as fenitrothion and parathion. Spectral and DFT (B3LYP/Lanl2DZ) calculations revealed that complexes 1 and 2 have a square-pyramidal environment around zinc(II) centers with coordination chromophores of ZnN4Cl and ZnN4O, respectively. Both 1 and 2 were used as a modifier in the construction of a biomimetic sensor for the determination of toxic OPs, fenitrothion and parathion, in phosphate buffer by square wave voltammetry. The hydrolysis of OPs using 1 or 2 generates p-nitrophenol, which is subsequently oxidized at the surface of the modified carbon past electrode. The catalytic activity of 2 was higher than 1, which is attributed to the higher electronegativity of the former. The oxidation peak potentials of p-nitrophenol were obtained at +0.97 V (vs. Ag/AgCl) using cyclic voltammetry (CV) and +0.88 V (vs. Ag/AgCl) using square wave voltammetry. Several parameters were investigated to evaluate the performance of the biomimetic sensor obtained after the incorporation of zinc(II) complex 1 and 2 on a carbon paste electrode (CPE). The calibration curve showed a linear response ranging between 1.0 μM (0.29 ppm) and 5.5 μM (1.6 ppm) for fenitrothion and 1.0 μM (0.28 ppm) and 0.1 μM (0.028 ppm) for parathion with a limit of detection (LOD) of 0.08 μM (0.022 ppm) and 0.51 μM (0.149 ppm) for fenitrothion and parathion, respectively. The obtained results clearly demonstrated that the CPE modified by 1 and 2 has a remarkable electrocatalytic activity towards the hydrolysis of OPs under optimal conditions.

The molecular complexes between barbituric acid (BU) and chloranilic acid (ChA) over graphitic nitride (g-C3N4) are investigated. The molecular complexes and the nanocomposite were investigated both in solid state and in methanol. The solid complexes and the corresponding nanocomposite were investigated using FTIR, TGA, and UV-Vis spectroscopy. The structures were explored using DFT calculations using wB97XD/ and def2-TZVP basis set. The DFT calculations revealed the formation of hydrogen-bonded complexes, which initiate the proton transfer from ChA to BU. Immobilization of the BUChA complex over the g-C3N4 sheet was stabilized by weak non-covalent interactions, such as π–π interactions. g-C3N4 facilitated the charge transfer process, which is beneficial for different applications.

A mixed ligand copper(II) complex, namely, [Cu(BPy)(Gly)Cl]⋅2H2O (CuC) (BPy=2,2′-bipyridine and Gly=glycine), was synthesized and characterized. The synthesized CuC complex was tested as inhibitor to effectively mitigate the corrosion of copper in alkaline solutions using the linear sweep voltammetry (LSV) and linear polarization resistance (LPR) techniques. For the sake of comparison, such two D.C. electrochemical techniques were also applied to the Cu/OH− interface in the presence of the two studied free ligands, namely, BPy and Gly. The results showed that the three studied compounds acted as mixed-type inhibitors, with CuC being the most efficacious one. The adsorption of the inhibitor is confirmed from X-ray photoelectron spectroscopy (XPS) profiles by the appearance of organic chlorine as well as pyridine and amine nitrogen bonds. Based on XPS data, it was presumed that the corrosion inhibitor stimulates the formation of Cu2CO3(OH)2 species at the electrode surface since, in the case of a corroded reference sample (in absence of inhibitors), its proportion is trivial. The reactivity of the isolated inhibitors was analyzed by computing several quantum chemical parameters based on the density functional theory (DFT). A good correlation was found between these parameters and the anticorrosive performance. Additionally, Monte Carlo simulation studies were applied to find the best configurational space of ligands and their complex on the Cu(111) surface.

Imidacloprid (Imid), a systemic neonicotinoid insecticide, is broadly used worldwide. It is reported to contaminate aquatic systems. This study was proposed to evaluate oxidative stress and genotoxicity of Imid on Nile tilapia (Oreochromis niloticus) and the protective effect of ascorbic acid (Asc). O. niloticus juveniles (30.4 ± 9.3 g, 11.9 ± 1.3 cm) were divided into six groups (n=10/replicate). For 21 days, two groups were exposed to sub-lethal concentrations of Imid (8.75 ppm, 1/20 of 72h-LC50 & 17.5 ppm, 1/10 of 72h-LC50); other two groups were exposed to Asc (50 ppm) in combination with Imid (8.75 & 17.5 ppm); one group was exposed to Asc (50 ppm) in addition to a group of unexposed fish which served as controls. Oxidative stress was assessed in the liver where the level of enzymatic activities including superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in addition to mRNA transcripts and, Lipid peroxidation (LPO) were evaluated. Moreover, mitotic index (MI) and comet assay were performed, in addition to the erythrocytic micronucleus (MN), and nuclear abnormalities (NA) were observed to assess genotoxicity in fish. Imid exposure induced significant (p˂ 0.05) changes in the antioxidant profile of the juveniles' liver by increasing the activities and gene expression of SOD, CAT and GPX as well as elevating the levels of LPO. DNA strand breaks in gill cells, erythrocytes and hepatocytes along with erythrocytic MN and NA were also significantly elevated in Imid-exposed groups. MI showed a significant (p˂ 0.05) decrease associated with Imid exposure. Asc administration induced a significant amelioration towards the Imid toxicity (8.75 & 17.5 ppm). A significant protective potency against the genotoxic effects of Imid was evidenced in Asc co-treated groups. Collectively, results highlight the importance of Asc as a protective agent against Imid-induced oxidative stress and genotoxicity in O. niloticus juveniles.

The waterborne acrylic resin modified by both itaconic acid (IA) and γ-methacryloxypropyl triisopropoxidesilane (KH571) was successfully synthesized by the seeded emulsion polymerization. The effects of IA and KH571 on the properties of waterborne acrylic resin, including mechanical properties, water resistance, thermal stability, storage stability and corrosion resistance, were studied. Fourier transform infrared spectroscopy analysis showed that IA and KH571 were successfully copolymerized with acrylic monomers. Compared with the unmodified resin, the introduction of IA and KH571 greatly improved the water resistance of the resin coating. When 2 wt% IA and 4 wt% KH571 were added, the contact angle of the resin coating increased from 78.91° to 90.49°. The water resistance time of the resin coating was improved from one day to 17 days. Additionally, the modified resin showed better mechanical properties, thermal stability, storage stability and corrosion resistance. The waterborne acrylic resin modified with IA and KH571 has a potential application prospect in the fields of waterproof and anticorrosive coating.

Type 2 diabetes mellitus (T2DM) and hypertension are common chronic diseases mainly associated with the development and progression of end-stage renal disease (ESRD) leading to morbidity and mortality. Gene polymorphisms linked to the renin–angiotensin (AGT)–aldosterone system (RAAS) were broadly inspected in patients with diabetic nephropathy (DN) and hypertension. This study aimed to investigate the association of AGT gene polymorphisms (rs699 and rs4762) with ESRD in T2DM hypertensive Egyptian patients. Genotyping of rs699 and rs4762 was conducted using the tetra-primers amplification refractory mutation system (ARMS-PCR). The allelic distribution analysis was performed on 103 healthy control subjects, 97 non-ESRD patients, and 104 patients with ESRD. The allelic frequencies of AGT gene polymorphisms (rs4762 and rs699) in all study participants were assessed. For the non-ESRD group, the frequencies of the alleles of AGT-rs4762 (χ2 = 31.88, p &lt, 0.001, OR = 5.17, CI 95%: 2.81–9.51) and AGT-rs699 (χ2 = 4.85, p = 0.027, OR = 1.56, CI 95%: 1.05–2.33) were significantly associated with the non-ESRD group. However, for the ESRD group, the T allele was significantly higher than that in the controls (χ2 = 24.97, p &lt, 0.001, odds ratio (OR) = 4.35, CI 95%: 2.36–8.02). Moreover, AGT (rs699) genotypes showed no significant difference between the ESRD group and controls. In conclusion, AGT gene polymorphisms rs699 and rs4762 were associated with non-ESRD versus controls, without any significant risk observed in all patient groups. However, the AGT (rs4762) variant showed a significant risk in the ESRD group in comparison to controls in Egyptians.

Objective Beehive air therapy is recognized as a potential remedy for treating asthma, bronchitis, lung fibrosis, and respiratory tract infections. Developed countries in which beehive air therapy is currently authorized include Germany, Hungary, Slovenia, and Austria. However, scientific proof of its efficacy is lacking which warrants further chemical and biological analyses as a proof of concept. In this study, beehive air volatile profile was determined for the first time along with its individual components (bees, venom, honey, and beeswax). Methods Volatile compounds were collected from beehive air using solid phase micro-extraction (SPME) coupled to gas chromatography-mass spectrometry (GC–MS). Antimicrobial assay of the air released from 4 beehive products was further performed against Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, and multi drug-resistant Staphylococcus aureus (MRSA) using the in vitro agar-well diffusion and microtiter plate assays. Results and conclusions: A total of 56 volatile compounds were identified from beehive air, venom, bee insect and wax air including 6 fatty acids, 6 alcohols, 10 aldehydes, 5 esters, 1 ether, 9 hydrocarbons, 1 phenol, 7 ketones, 1 nitrogenous compound and 10 terpenes. The most abundant constituents were short-chain fatty acids (26.32%) while the lowest were the nitrogenous compounds (0.82%). The principal component analysis (PCA) scores plot of the UPLC/MS dataset showed the similarity of the beehive air to the insect bee's aroma profile. With regards to antimicrobial assay, beehive air and venom exerted the strongest antimicrobial activity among the examined bee products against S. aureus, K. pneumoniae, A. baumannii, and MRSA in agar-well diffusion assay but failing to exert an effect using microtiter plate assay as in case of bee venom against the aforementioned bacteria.

Imidacloprid (Imid), a systemic neonicotinoid insecticide, is broadly used worldwide. It is reported to contaminate aquatic systems. This study was proposed to evaluate oxidative stress and genotoxicity of Imid on Nile tilapia (Oreochromis niloticus) and the protective effect of ascorbic acid (Asc). O. niloticus juveniles (30.4 ± 9.3 g, 11.9 ± 1.3 cm) were divided into six groups (n = 10/replicate). For 21 days, two groups were exposed to sub-lethal concentrations of Imid (8.75 ppm, 1/20 of 72 h-LC50 and 17.5 ppm, 1/10 of 72 h-LC50); other two groups were exposed to Asc (50 ppm) in combination with Imid (8.75 and 17.5 ppm); one group was exposed to Asc (50 ppm) in addition to a group of unexposed fish which served as controls. Oxidative stress was assessed in the liver where the level of enzymatic activities including superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in addition to mRNA transcripts and, Lipid peroxidation (LPO) were evaluated. Moreover, mitotic index (MI) and comet assay were performed, in addition, the erythrocytic micronucleus (MN), and nuclear abnormalities (NA) were observed to assess genotoxicity in fish. Imid exposure induced significant (p ˂ 0.05) changes in the antioxidant profile of the juveniles' liver by increasing the activities and gene expression of SOD, CAT and GPX as well as elevating the levels of LPO. DNA strand breaks in gill cells, erythrocytes and hepatocytes along with erythrocytic MN and NA were also significantly elevated in Imid-exposed groups. MI showed a significant (p ˂ 0.05) decrease associated with Imid exposure. Asc administration induced a significant amelioration towards the Imid toxicity (8.75 and 17.5 ppm). A significant protective potency against the genotoxic effects of Imid was evidenced in Asc co-treated groups. Collectively, results highlight the importance of Asc as a protective agent against Imid-induced oxidative stress and genotoxicity in O. niloticus juveniles.

International audience; Two charge transfer complexes, namely [(BDAH)(+)(PA(-))] CT1 [(BTAH)(2+) (PA(-))(2)] and CT2 (BDAH = 1,2-benzenediamine, BTAH = 1,2,4,5-benzenetetramine, and PA(-) = 2,4,6-trinitrophenolate), were synthesized and fully characterized using various spectroscopic techniques. CT1 and CT2 were tested as inhibitors to effectively control the uniform and anodic corrosion processes of copper in an alkaline electrolyte (1.0 M KOH) using various electrochemical techniques. As a reference point, results were compared with the potassium salt of the pi-acceptor potassium 2,4,6-trinitrophenolate (designated here as PA(-)K(+)). The highest inhibition efficiency (97%) was recorded for inhibitor CT2 at a concentration of 1.0 mM. The inhibition mechanism was discussed based on scanning electron microscopy and X-ray photoelectron spectroscopy results of the corroded and inhibited Cu surfaces. A theoretical study, based on quantum-chemical calculations of the synthesized compounds. performed by the DFF/B3LYP method with a 6-311++G(2d,2p) basis set by using Gaussian 09, Revision A.02 program, was also included to support experimental findings. The various quantum chemical parameters such as E-HOMO, E-LUMO, chemical hardness, and chemical softness of the investigated molecules were calculated, and their correlation with the inhibition efficiency of the synthesized compounds was discussed. (C) 2020 Elsevier B.V. All rights reserved.

In the present paper, a simple and fast one pot process to prepare hybrid metal/semiconductor nanocomposites (NCs) using a simple polyol method is discussed. The Nanoparticle sizes of the hybrid nanocomposite range between 20 and 30 nm. This protocol involves the use only of 1,3 propanediol as solvent and platinum(IV) and zinc(II) as precursors without the need to use any surfactant or reducing agent. The formation of platinum nanoparticles (PtNPs) was observed first (before the boiling point) followed by the zinc oxide (ZnO) nanoparticles which started to form when the temperature reached boiling point (190 °C). The reaction then continued for 30 min. To study the doping effect on the optical properties of the hybrid nanomaterials obtained, Cu(II), Fe(II), Co(II) and Ni(II) were used as cationic dopants. The same protocol was maintained with the only exception being that the required amount of the doping element was added according to a well determined ratio (R = Zn(II):M(II), where M = Cu, Fe, Co, or Ni). Full characterization was conducted using various techniques (such as X-ray diffraction, transmission electron microscopy, DTA/TGA, X-ray fluorescence, etc.) to reveal the purity, morphology, stability and the intrinsic properties of the obtained hybrid Pt–ZnO/M nanocomposites (where M = Cu, Fe, Co or Ni). Compared to bare ZnO or Pt–ZnO, the new hybrid NCs exhibit a better stability (up to 600 °C) and an important change in the optical properties. This change makes them new promising hybrid nanomaterials for many applications especially in photocatlytic and renewable energy applications.

Elegant process for synthesis of 3-(7H-dibenzo[c,h]xanthen-7-yl)benzaldehyde(3), as new starting material to create a set of novel xanthene analogues, 2-(3-(7H-dibenzo[c,h]xanthen-7-yl)benzylidene)malononitrile(4), 3-(3-(7H-dibenzo[c,h]xanthen-7-yl)phenyl)-2-cyanoacrylic acid(5), and Ethyl-3-(3-(7H-dibenzo[c,h]xanthen-7-yl)phenyl)-2-cyanoacrylate(6), was achieved starting with available materials under mild conditions. Various concentrations (ca. 0.1–1.0 mM) of the synthesized cyano-benzylidene xanthene derivatives, namely compounds3, 4, 5, and 6, were tested as inhibitors to control copper corrosion in alkaline solutions employing polarization and electrochemical impedance spectroscopy (EIS) measurements. Results revealed that the four studied xanthenes derivatives served as efficient (mixed-type) inhibitors. The inhibition efficiency increased with increase in inhibitor concentration.The inhibition performance of studied compounds varied according to their chemical structures. The best inhibitor, compound5, achieved a maximum inhibition efficiency of 98.7% (calculated from corrosion current densities) and ∼95% (estimated from charge-transfer resistance values) at a concentration of 1.0 mM. The morphology of the corroded and inhibited copper surfaces was studied by scanning electron microscopy (SEM). The adsorption of the inhibitor molecules was confirmed by high-resolution X-ray photoelectron spectroscopy (XPS) profiles. XPS data were used to comparethe inhibition efficiencies exhibited by studied compounds. The oxidation rate of the Cu surface wasfound to be frivolous, referring to high inhibition efficiency, only in the presence of inhibitor(5), and Cu0share is 87% of all copper components. The shares of Cu0were significantly reduced to 43%, 26% and 20%for inhibitors(3),(4)and(6), respectively. These findings go parallel with the results obtained from electrochemical measurements. The quantum-chemical calculations of the investigated molecules were performed to support electrochemical findings, and their correlations with the inhibition efficiency of the synthesized compounds were discussed.

Considering the thiophene unit as an electron-rich heterocycle, it is investigated with the aim of elucidating its potential efficiency for solar cell application. With the introduction of active substituents such as COOEt, CONH2 and CN into the thiophene segment, three novel thieno pyridine sensitizers (6a&ndash, c), based on donor-acceptor D-&pi, A construction, are designed and synthesized. The effect of the anchoring groups is investigated based on their molecular orbital&rsquo, s (MO&rsquo, s) energy gap (Eg). The electrostatic interaction between the synthesized dyes and metal nanoparticles, namely gold, silver and ruthenium, is believed to improve their performance as organic sensitizers. The dye-sensitized solar cells (DSSCs) are manufactured using the novel diazenyl pyridothiophene dyes, along with their metal nanoparticles conjugates as sensitizers, and were examined for efficiency improvement. Accordingly, using this modification, the photovoltaic performance was significantly improved. The promising results of conjugate (6b/AgNPs), compared with reported organic and natural sensitizers (JSC (1.136 &times, 10&minus, 1 mA/cm2), VOC (0.436 V), FF (0.57) and &eta, (2.82 &times, 2%)), are attributed to the good interaction between the amide, methyl, amino and cyano groups attached to the thiophene pyridyl scaffolds and the surface of TiO2 porous film. Implementation of a molecular modeling study is performed to predict the ability of the thiophene moiety to be used in solar cell applications.