Multifunctional Silver(I) Complexes with Metronidazole Drug Reveal Antimicrobial Properties and Antitumor Activity against Human Hepatoma and Colorectal Adenocarcinoma Cells

Silver salts and azole derivatives are well known for their antimicrobial properties. Recent evidence has demonstrated also their cytotoxic and genotoxic potential toward both normal and cancer cells. Still, little is known about the action of complexes of azoles with silver(I) salts. Thus, the goal of the study was to compare the chemical, cytotoxic and antimicrobial properties of metronidazole complexes with silver(I) nitrate and silver(I) sulfate to metronidazole and pure silver(I) salts. We synthetized a novel complex, [Ag(MTZ)2]2SO4, and confirmed its chemical structure and properties using 1H and 13C NMR spectroscopy and X-Ray, IR and elemental analysis. To establish the stability of complexes [Ag(MTZ)2NO3] and [Ag(MTZ)2]2SO4, they were exposed to daylight and UV-A rays and were visually assessed. Their cytotoxicity toward human cancer cells (HepG2, Caco-2) and mice normal fibroblasts (Balb/c 3T3 clone A31) was determined by MTT, NRU, TPC and LDH assays. The micro-dilution broth method was used to evaluate their antimicrobial properties against Gram-positive and Gram-negative bacteria. A biofilm eradication study was also performed using the crystal violet method and confocal laser scanning microscopy. The photo-stability of the complexes was higher than silver(I) salts. In human cancer cells, [Ag(MTZ)2]2SO4 was more cytotoxic than Ag2SO4 and, in turn, AgNO3 was more cytotoxic than [Ag(MTZ)2NO3]. For Balb/c 3T3 cells, Ag2SO4 was more cytotoxic than [Ag(MTZ)2]2SO4, while the cytotoxicity of AgNO3 and [Ag(MTZ)2NO3] was similar. Metronidazole in the tested concentration range was non-cytotoxic for both normal and cancer cells. The complexes showed increased bioactivity against aerobic and facultative anaerobic bacteria when compared to metronidazole. For the majority of the tested bacterial strains, the silver(I) salts and complexes showed a higher antibacterial activity than MTZ; however, some bacterial strains presented the reverse effect. Our results showed that silver(I) complexes present higher photo-stability, cytotoxicity and antimicrobial activity in comparison to MTZ and, to a certain extent, to silver(I) salts

SARS-CoV-2 Seroprevalence in Healthcare Workers before the Vaccination in Poland: Evolution from the First to the Second Pandemic Outbreak

Healthcare workers (HCWs) are on the frontline, struggling with the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To describe recent or past infections, the serological assays enabled the assessment of the immune response developed in coronavirus disease (COVID-19) in the period when testing was hardly available. In this study, we investigated SARS-CoV-2 seroprevalence in HCWs in a Polish teaching hospital and the Regional Occupational Medicine Center after both the first and the second waves. ELISA-based tests for anti-SARS-CoV-2 IgA and IgG were used to determine immune response to SARS-CoV-2 in volunteer HCWs who worked in those institutions in May 2020 (208 participants aged 47.1 ± 12.5, 88% women) and in December 2020 (179 participants aged 45.2 ± 12.4, 86% woman). Risk factors for seropositivity were also assessed using a questionnaire filled out by all participants. We reported a significant increase in seroprevalence after the second wave (22.9%) compared with the first outbreak (2.4%) (OR 12.1; 95%CI 4.6–31.3; p < 0.0001). An association between IgG seroprevalence and severity of infections was noted. Furthermore, we demonstrated that amongst medical personnel, nurses exhibited a proportionally higher SARS-CoV-2 seroprevalence. Moreover, given the high seroprevalence in non-clinical group of HCWs, we suggest that community transmission can play a superior role to workplace exposure

Differentiation by random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) of Candida albicans isolated from upper respiratory tract in patients with non-small cell lung cancer

Cancer patients are predisposed to fungal infections caused by Candida albicans, especially to oral or respiratory tract candidiasis. The aim of this study was to estimate genetic diversity by RAPD-PCR (random amplified polymorphic DNA-polymerase chain reaction) of C. albicans isolated from upper respiratory tract of 100 patients with non-small cell lung cancer. Among 52 strains, 34 genotypes were defined. 10 clusters comprising 28 (53.85%) isolates with similarity coefficient ≥ 80% were formed. The remaining 24 (46.15%) isolates represented individual genotypes. The RAPD-PCR technique revealed genomic variability within C. albicans isolated from upper respiratory tract of the cancer patients

Chemical composition and microbiological evaluation of essential oil from Hyssopus officinalis L. with white and pink flowers

Hyssopus officinalis L. is a common plant that is most usually found in three color forms - f. cyaneus (blue), f. ruber Mill. (purple/pink) and f. albus Alef (white). In the present work, we evaluated the chemical composition and antimicrobial activity of essential oils obtained from Polish-sourced white- and pink-flowered H. officinalis. Gas chromatography-mass spectrometry analysis of the essential oil has shown that both forms of color have a different content of main components. The principle essential oil component of white-flowered H. officinalis L. was pinocamphone (51%), while pink-flowered H. officinalis L. contained almost equal amounts of pinocamphone (28.8%) and isopinocamphone (21.9%). Of note, the essential oil of the pink form was more active against Grampositive bacteria, especially against Bacillus subtilis

In vitro susceptibility of oral Candida albicans isolates to chlorhexidine

Fungal infections are an important medical problem in patients from different risk groups. The majority of these infections are caused by Candida spp., with over 50 % due to C. albicans. The purpose of the study was to evaluate in vitro chlorhexidine effect on C. albicans colonizing the mouth and throat isolated from 5 population groups. The study material included the reference strains of C. albicans ATCC 2091 and C. albicans ATCC 10231, routinely used for evaluation of antimicrobials, and 120 clinical isolates of C. albicans from: hospitalized cancer patients (30 isolates), chronic HCV patients (31 isolates), immunocompromised patients (28 isolates), healthy school-age children (31 isolates), elderly people – aged 65 years or older (30 isolates). Chlorhexidine inhibited the growth of C. albicans at the concentrations of 0.625-5 µg/ml (in particular, 2.5 µg/ml solution was effective against strains from immunocompromised patients and 5 µg/ml – against the remaining isolates). The yeasts were also killed by 2.5-20 µg/ml chlorhexidine solutions. The concentration of 5 µg/ml was particularly active against the strains isolated from the elderly, immunocompromised and lung cancer patients, while 10 µg/ml inhibited the growth of the strains from the remaining two groups. Moreover, C. albicans isolates from hepatitis C patients and healthy children comparing to strains from the elderly were less sensitive to chlorhexidine fungicidal effect and these differences were statistically significant. According to our studies, the fungicidal effect of chlorhexidine seems to depend on the origin of the tested oral C. albicans strains from various patient groups

Double Palindrome Water Chain in Cu(II) Theophylline Complex. Synthesis, Characterization, Biological Activity of Cu(II), Zn(II) Complexes with Theophylline

Two metal complexes of theophylline were synthesized. Namely, 1 with the formula [Cu(theop)2(H2O)3]·2H2O and 2, [Zn(theop)2]∙H2O (where: theop = theophylline ion). Their properties were thoroughly investigated by the elemental analysis (EA), flame atomic absorption spectrometry (FAAS), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA) that were augmented by antimicrobial and antioxidant analyses. Their radical scavenging ability (RSA) is notably higher than that of a pure theophylline itself. Similarly to theophylline complexes already studied by us 3, [Mn(theop)2(H2O)4] 4, [Co(theop)2(H2O)4] and 5, [Ni(theop)2(H2O)4] title compounds are inactive against Gram-negative bacteria, but they show moderate or mild activity against Gram-positive rods. The low temperature, single crystal X-ray diffraction technique determines the crystal structure of 1. Its supramolecular crystal topology is affected by the unique, double palindrome water chain that formed by two conserved and a sole coordinated water molecules. Crystal packing arrangements were characterized by fingerprint plots that were derived from the Hirshfeld surfaces (HS), as calculated for all structures in the series 1, 3, 4, 5