Flow injection analysis of mercury using 4-(dimethylamino) benzaldehyde-4-ethylthiosemicarbazone as the ionophore of a coated wire electrode

Discovery and Mechanistic Studies of Dual-Target Hits for Carbonic Anhydrase IX and VEGFR-2 as Potential Agents for Solid Tumors: X-ray, In Vitro, In Vivo, and In Silico Investigations of Coumarin-Based Thiazoles

A dual-targeting approach is predicted to yield better cancer therapy outcomes. Consequently, a series of coumarin-based thiazoles (5a-h, 6, and 7a-e) were designed and constructed as potential carbonic anhydrase (CA) and VEGFR-2 suppressors. The inhibitory actions of the target compounds were assessed against CA isoforms IX and VEGFR-2. The assay results showed that coumarin-based thiazoles 5a, 5d, and 5e can effectively inhibit both targets. 5a, 5d, and 5e cytotoxic effects were tested on pancreatic, breast, and prostate cancer cells (PANC1, MCF7, and PC3). Further mechanistic investigation disclosed the ability of 5e to interrupt the PANC1 cell progression in the S stage by triggering the apoptotic cascade, as seen by increased levels of caspases 3, 9, and BAX, alongside the Bcl-2 decline. Moreover, the in vivo efficacy of compound 5e as an antitumor agent was evaluated. Also, molecular docking and dynamics displayed distinctive interactions between 5e and CA IX and VEGFR-2 binding pockets.

A biodegradable film based on cellulose and thiazolidine bearing UV shielding property

The current rationale is exploring new eco-friendly UV- shielding films based on cellulose and thiazolidine. Cellulose was oxidized to dialdehyde cellulose (DAC) and tricarboxy cellulose (TCC) by periodate and TEMPO/periodate/hypochlorite, respectively. While E-3-amino-5-(phenyldiazenyl)-2-thioxothiazolidin-4-one (TH) was synthesized by coupling diazonium salt with the 5-methylene of 2-thioxo-4-thiazolidinone. DAC was then coupled with TH via Schiff base reaction and incorporated onto TCC with different ratios to get UV-shielding films. ¹HNMR, infrared spectroscopy (FTIR), and thermal gravimetric analysis (TGA) were used to investigate the chemical structure of the synthesized materials. In addition, the films' morphology, thermal, mechanical, and UV-shielding properties were investigated. The UV-shielding studies revealed that the film with 10% DAC-TH has 99.88, 99.99, and 96.19% UV-blocking (UVB), UV-absorbance (UVA), and Ultra-violet protection (UPF), respectively. Moreover, the prepared films demonstrated promising antimicrobial activity against Escherichia coli, S. aureus, P. aeruginosa, and Candida albicans. Finally, the prepared films showed no cytotoxic effects on normal human skin fibroblast's HFB-4 cell line.

Mercury in dental amalgam: Are our health care workers at risk?

Dental amalgam in fillings exposes workers to mercury. The exposure to mercury was investigated among 1871 dental health care workers. The aim of the study was to evaluate the risk of mercury exposure among dental compared to nondental health care workers and to determine other risk factors for mercury exposure. Respondents answered questionnaires to obtain demographic, personal, professional, and workplace information and were examined for their own amalgam fillings. Chronic mercury exposure was assessed through urinary mercury levels. In total, 1409 dental and 462 nondental health care workers participated in the study. Median urine mercury levels for dental and nondental health care workers were 2.75 μg/L (interquartile range [IQR] = 3.0175) and 2.66 μg/L (IQR = 3.04) respectively. For mercury exposure, there were no significant risk factor found among the workers involved within the dental care. The Mann-Whitney test showed that urine mercury levels were significantly different between respondents who eat seafood more than 5 times per week compared to those who eat it less frequently or not at all (p = 0.003). The urinary mercury levels indicated significant difference between dental workers in their practice using squeeze cloths (Mann-Whitney test, p = 0.03). Multiple logistic regression showed that only the usage of cosmetic products that might contain mercury was found to be significantly associated with the urinary mercury levels (odds ratio [OR] = 15.237; CI: 3.612-64.276). Therefore, mean urinary mercury levels of health care workers were low. Exposure to dental amalgam is not associated with high mercury exposure. However, usage of cosmetic products containing mercury and high seafood consumption may lead to the increase of exposure to mercury.

IMPLICATIONS

Exposure to the high levels of mercury from dental amalgam can lead to serious health effects among the dental health care workers. Nationwide chronic mercury exposure among dental personnel was assessed through urinary mercury levels. Findings suggest low urinary mercury levels of these health care workers. Exposure to dental amalgam is not associated with high mercury exposure. However, the usage of cosmetic products containing mercury and high seafood consumption may lead to the increase of exposure to mercury.

A novel potentiometric self-plasticizing polypyrrole sensor based on a bidentate bis-NHC ligand for determination of Hg(ii) cation

In this approach, a new potentiometric self-plasticizing polypyrrole sensor was constructed based on a bidentate bis-NHC ligand for the purpose of Hg²⁺cation determination.

A new electrochemical sensor based on task-specific ionic liquids-modified palm shell activated carbon for the determination of mercury in water samples

In this study, a potentiometric sensor composed of palm shell activated carbon modified with trioctylmethylammonium thiosalicylate (TOMATS) was used for the potentiometric determination of mercury ions in water samples. The proposed potentiometric sensor has good operating characteristics towards Hg (II), including a relatively high selectivity; a Nernstian response to Hg (II) ions in a concentration range of 1.0 × 10(-9) to 1.0 × 10(-2) M, with a detection limit of 1 × 10(-10) M and a slope of 44.08 ± 1.0 mV/decade; and a fast response time (~5 s). No significant changes in electrode potential were observed when the pH was varied over the range of 3-9. Additionally, the proposed electrode was characterized by good selectivity towards Hg (II) and no significant interferences from other cationic or anionic species.