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Heavy metals are particularly damaging contaminants in the environment, and even trace concentrations represent a risk to human health due to their toxicity. To detect the heavy metals of Mn 2+ and Co 2+ ions, a novel selective reusable paper-based Fluorescence naked-eye sensor based on naphthalene cationic Schiff base (NCSB) was synthesized and confirmed using FT-IR, 1  H-NMR, and MS tools. Based on a blue to colorless color change in the aqueous solution, the NCSB sensor is utilized to Mn 2+ and Co 2+ cations selectively among other metal ions (Fe 2+ , Cu 2+ , Mg 2+ , Ni 2+ , Zn 2+ , Cd 2+ , Hg 2+ , Pb 2+ , Sn 2+ and Cr 3+ ). In the aqueous medium, the NCSB sensor displayed high sensitivity, with limits of detection (LOD) values of 0.014 µM (14.08 nM) and 0.041 µM (41.47 nM) for Mn 2+ and Co 2+ cations, respectively. The paper-based sensor naked-eye detected Mn 2+ and Co 2+ cations in water at concentrations as low as 0.65 µM (65 nM) and 0.086 µM (86 nM), respectively. It was discovered that 5 min of incubation time and a pH range of 7 to 11 were optimal for the complexation reaction between the Mn 2+ and Co 2+ ions and the NCSB sensor. Through a static quenching process, the interaction of the different metal ions with the Schiff base group in the NCSB molecule results in the development of a ground-state non-fluorescent complex. NCSB sensor was also successfully applied in analysis of Mn 2+ and Co 2+ in environmental water with good recoveries of 94.8-105.9%. The theoretical calculations based on density functional theory (DFT) studies are in support of experimental interpretations. The links between the input factors and the anticipated response were evaluated using the quadratic model of the response surface methodology (RSM) modeling., (© 2023. The Author(s).)

The present study evaluated the antiparasitic effect of curcumin extract on Schistosoma mansoni in Swiss albino mice. The experimental design included four groups of S. mansoni - infected mice; without treatment (controls), curcumin-treated, Praziquantel (PZQ)-treated, and PZQ +curcumin treated mice. The results showed that curcumin improved ISHAK confluent necrosis score up to zero. PZQ +curcumin showed a significant reduction in portal inflammation. Both activity and fibrosis demonstrated lower scores in all treated groups, however, PZQ revealed a marked increase in confluent necrosis and interface hepatitis. Besides, the lobular inflammation revealed worsening in the overall ISHAK score in all treated groups compared with the control. Few periocular granulomas were recovered by PZQ +curcumin treatment at day 35 post-treatment (6±1.2), P-value <0.05. Curcumin revealed a mild reduction (60±7.376). Curcumin-treated groups, with and without PZQ, resulted in higher significant Immunoreactivity score (IRS) for Bcl-2-associated X (BAX) and lower Interleukine- 17A (IL-17A), and Human epidermal growth factor (EGF), compared to the control. However, PZQ revealed a lower mean IRS value in BAX, higher IL-17A and EGF in the periovulatory granuloma. It was concluded that PZQ +curcumin treatment had a potent synergistic outcome through lessening the number of granulomas, the inflammatory events, and the expression of EGF, and amelioration of apoptosis in the periovulatory granulomas if compared with either PZQ or curcumin alone.

Trichinella spiralis larvae have very special characters that make them able to completely transform the function of the affected muscle cells towards a self-serving environment, offering them nourishment and protection via what is known as "nurse cells". This setting may be affected by drugs that are used for the treatment of co-morbidities and co-infections as calcium channel blockers, which are widely used in clinical practice. In the present study, the effects of verapamil, ivermectin (IVM), and their combined administration on the parasitic burden, immuno-pathology and angiogenesis were investigated during experimental trichinellosis. Estimation of intestinal adult parasitic stages and muscle larvae was done. VEGF gene expression and CD31 immunohistochemical local expression were measured to investigate angiogenesis, in addition to histopathological examination to explore the extent of inflammation. Although verapamil did not have an effect on the adult worm count during the intestinal phase, it induced an anti-inflammatory effect on intestinal pathology. During the muscle phase, it was very effective in reducing the larval count by 93.78%. IVM effectively reduced the worm count by 85.34%, and the muscle larval count by 97.84%, while combined verapamil and IVM administration resulted in a significant reduction in both adult parasites by 69.5% and larval stages by 99%. Both verapamil and IVM and their combination induced a potent decrease in local CD31 protein expression and VEGF gene expression. The important role of calcium and calcium channels during the pathology of trichinellosis, in addition to the pivotal role of calcium on biological processes such as immunity and angiogenesis, make calcium-channel blockers promising candidates for drug repurposing in the management of helminthic infection., Competing Interests: The authors whose names are listed immediately below certify that they have NO affiliations with or involvement in any organization or entity with any financial interest (such as honoraria; educational grants; participation in speakers' bureaus; membership, employment, consultancies, stock ownership, or other equity interest; and expert testimony or patent-licensing arrangements), or non-financial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript., (© 2022 The Authors.)

The design of multifunctional sensors based on biocompatible hybrid materials consisting of conjugated polythiophene-quantum dots for multiple environmental pollutants is a promising strategy for the development of new monitoring technologies. Herein, we present a new approach for the "on-off-on" sensing of Hg 2+ and triacetone triperoxide (TATP) based on amphiphilic polythiophene-coated CdTe QDs (PQDs, PLQY ∼78%). The emission of the PQDs is quenched by Hg 2+ ions via electron transfer interactions. Based on the strong interaction between TATP and Hg 2+ ions, the addition of TATP to the PQD-Hg 2+ complex results in a remarkable recovery of the PQD emission. Under the optimized conditions, the PQD sensor shows a good linear response to Hg 2+ and TATP with detection limits of 7.4 nM and 0.055 mg L -1 , respectively. Furthermore, the "on-off-on" sensor demonstrates good biocompatibility, high stability, and excellent selectivity in the presence of other metal ions and common explosives. Importantly, the proposed method can be used to determine the level of Hg 2+ and TATP in environmental water samples.

Three novels amide Gemini cationic surfactants with various alkyl chains and their silver nanohybrid with silver nanoparticles were synthesized and a confirmation study for surfactant and their nanoparticles formation has been established using IR, 1 HNMR, TEM and UV-Vis spectroscopy. The surface-active properties of these surfactants and their nanoform were investigated through surface tension and electrical conductivity measurements and a comparative study has been established. The thermodynamic parameters of micellization and adsorption were assessed at temperatures range from 25 to 65°C. The effect of silver particles on the surface behavior of the synthesized surfactant has been discussed. The aggregation behavior of silver nanoparticles with these synthesized Gemini surfactants in water were investigated using dynamic light scattering and transmission electron microscopy. Furthermore, the antimicrobial activities of these synthesized amide Gemini surfactants and their nanostructure with silver against both Gram positive and Gram negative bacteria were also investigated., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Glaucoma is a serious chronic ophthalmic disease since it causes irreversible visual disability if untreated can lead to blindness. Treatment options include medications (classified into five major classes of drugs which are muscarinic cholinergic agonists, alpha-2 adrenergic agonists, beta-1 adrenergic antagonists, prostaglandins [PGs], and carbonic anhydrase inhibitors); use of laser therapy or conventional surgery. Pharmacoeconomic analysis helps in choosing among this variety of treatments. There is a great need for such analysis in Egypt since undergoing of it in different countries or societies may produce different results. This work aimed to compare cost-effectiveness of bimatoprost 0.03% once daily versus brimonidine 0.2% twice daily and timolol 0.5% twice daily as monotherapy treatment in Egyptian patients with open-angle glaucoma or ocular hypertension. Clinical data revealed that all treatments decreased intraocular pressure (IOP) significantly but bimatoprost 0.03% showed the highest efficacy (27.7% decrease in IOP from baseline), while timolol 0.5% reduced IOP by 22.5% then brimonidine 0.2% which decreased IOP by 20.8%. From the cost-effectiveness view, it would be preferable to initiate treatment with timolol in case of absence of any contraindications. PG analog can be used as add-on therapy in low responder patients or as alternative treatment in case of presence of contraindication to use of beta blockers., Competing Interests: There are no conflicts of interest.

Fluorescein (resorcinolphthalein) is a synthetic organic photoactive dye compound soluble in water, alcohol and polar solvents. It is widely used as a fluorescent tracer in medicinal and biological applications and tumor infected tissues tracer. In this study, fluorescein (F) was condensed by five coupling agents namely: p,p-phenylene diamine, p-hydroxy aniline, o-hydroxy aniline, p-methoxy aniline and p-methyl aniline in a molar ratio of 2(F):1 (coupling agent). The chemical structures of the synthesized fluorescein derivatives were confirmed using: microelemental analysis, FTIR spectroscopy, 1H-NMR spectroscopy, and mass spectroscopy. The synthesized compounds were loaded on chemically prepared silver nanoparticles via reduction reaction of silver nitrate. The structures and properties of the formed fluorescein derivatives silver nanohybrids were determined using: UV/Vis spectroscopy, TEM images and dynamic light scattering (DLS). The synthesized compounds and their nanohybrids were evaluated for their antimicrobial activities against different bacterial strains and fungi. The results showed that the formed fluorescein derivatives silver nanohybrids are in moderate diameter range, and the loading of the synthesized compounds protect the silver nanoparticles against coagulation. The antimicrobial activity against the studied microorganisms was comparable to the standard used. Moreover, the antimicrobial activity was increased considerably in case of using fluorescein derivatives silver nanohybrids. The antimicrobial activities were correlated to the chemical structures of the compounds, diameter of the formed nanohybrids and to the nature of the tested bacterial strains. The mechanism of the antimicrobial action of the synthesized compounds and their nanohybrids was proposed., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In the present study, chitosan assembled on gold and silver nanoparticles were prepared and characterized by UV-vis, TEM, EDX and DLS techniques. The nanocomposites chitosan (Ch)/clay, chitosan (Ch)/AgNPs/clay and chitosan (Ch)/AuNPs/clay were prepared by solution mixing method and characterized by FTIR, XRD, and SEM techniques. The adsorption of copper(II) ions onto the prepared hybrid composites from an aqueous solution using batch adsorption was examined. The results showed that benefiting from the surface property of clay, the abundant amino and hydroxyl functional groups of chitosan, the adsorbent provides adequate and versatile adsorption for the Cu(II) ions under investigation. The batch adsorption experiments showed that the adsorption of the Cu(II) is considerably dependent on pH of milieu, the amount of adsorbent, and contact time. Batch adsorption studies revealed that the adsorption capacity of Cu(II) increased with increase in initial concentration and contact time with optimum pH in the range around neutral. The maximum uptake of Cu(II) ions by (Ch)/AgNPs/clay composite was found to be 181.5mg/g. The adsorption efficiency of Cu(II) ions by prepared (Ch)/AgNPs/clay and (Ch)/AuNPs/clay is bigger than that the individual chitosan (Ch)/clay composite which clarifies the role of metal nanoparticles in enhancement the adsorption characters. The study suggests that the (Ch)/AgNPs/clay hybrid composite is a promising nano-adsorbent for the removal of Cu(II) ions from aqueous solution., (Copyright © 2016 Elsevier B.V. All rights reserved.)