Selenium nanoparticles: influence of reducing agents on particle stability and antibacterial activity at biogenic concentrations.

Selenium nanoparticles (SeNPs) have recently attracted attention for their antimicrobial and anticancer activities. Nevertheless, their use remains limited due to stability issues. The objective of this study is to investigate the impact of different reaction conditions (including the reducing and stabilizing agents, as well as reaction temperature) on the water dispersion characteristics, stability, and biological activity of SeNPs.

Gold(I) N-heterocyclic carbene complexes show strong proapoptotic, antioxidant and anti-inflammatory effects in A2780 and endothelial cells.

A series of eight gold(I) N-heterocyclic carbene (NHC) complexes [Au(IMes)(Ln)] based on 1,3-bis(2,4,6-trimethylphenyl)imidazole-2-ylidene (IMes) and 7-azaindole derivatives (HLn), where n = 1-8 for HL1 = 5-fluoro-7-azaindole, HL2 = 5-bromo-7-azaindole, HL3 = 3-chloro-7-azaindole, HL4 = 3-iodo-7-azaindole, HL5 = 5-bromo-3-chloro-7-azaindole, HL6 = 5-bromo-3-iodo-7-azaindole, HL7 = 4-chloro-2-methyl-7-azaindole and HL8 = 7-azaindole, was prepared, characterised and studied for their in vitro anti-cancer and anti-inflammatory effects. The complexes showed significant cytotoxicity on human ovarian cancer cell lines (A2780, IC ≈ 8-19 μM and A2780R, IC ≈ 8-19 μM) and lowered toxicity in normal HaCat and MRC-5 cells. Cellular effects of the selected complexes 1 and 7 were evaluated in A2780 cells using flow cytometry.

The effect of a varying pyridine ligand on the anticancer activity of Diiron(I) bis-cyclopentadienyl complexes.

The new diiron complexes [FeCp(CO)(L)(μ-CO){μ-CN(Me)(Cy)}]CFSO (L = pyridine, 3a; 4-aminopyridine, 3b; 4-dimethylaminopyridine, 3c; 4-trifluoromethylpyridine, 3d; nicotinic acid, 4; Cp = η-CH, Cy = CH = cyclohexyl) were synthesized in moderate to high yields using two distinct synthetic routes from the precursors 1 (L = CO, for 4) and 2 (L = NCMe, for 3a-d), respectively. All products were characterized by IR and multinuclear NMR spectroscopy, and the structures of 3b and 3d were ascertained by X-ray diffraction studies. The behavior of the complexes in aqueous solutions (solubility, Log P, stability) was assessed using NMR and UV-Vis methods.

Single Atom Engineered Antibiotics Overcome Bacterial Resistance.

The outbreak of antibiotic-resistant bacteria, or "superbugs", poses a global public health hazard due to their resilience against the most effective last-line antibiotics. Identifying potent antibacterial agents capable of evading bacterial resistance mechanisms represents the ultimate defense strategy. This study shows that -the otherwise essential micronutrient- manganese turns into a broad-spectrum potent antibiotic when coordinated with a carboxylated nitrogen-doped graphene.

Cellular Effects of Cationic Copper(II) Schiff Base Complexes: Anti-Inflammatory and Antiproliferative Properties.

A series of potassium isothiocyanato-(N-salicylidene-aminoacidato) cuprates (1-5) with the general formula of the monomeric unit K[Cu(sal-aa)(NCS)] ⋅ xHO (x=0 or 2), containing a Schiff-base ligand (Hsal-aa) derived from natural amino acids such as glycine, DL-α-alanine, DL-valine, DL-phenylalanine and β-alanine, and salicylaldehyde, was screened for in vitro antiradical and major cellular effects against selected cancerous and normal cells. The complexes exhibited strong antioxidant properties against superoxide in vitro and a protective effect on DNA under Fenton-like reaction conditions. Screening of their cellular effects revealed moderate in vitro cytotoxicity against human cancer cell lines (A2780, A2780R and MCF-7), with IC values of 25-35 μM, and relatively low toxicity to normal fibroblast MRC-5 cells (with IC values>50 μM).

Effects of midazolam on high-frequency oscillations in amygdala and hippocampus of epilepsy patients.

High-frequency oscillations (HFOs) are associated with normal brain function, but are also increasingly recognized as potential biomarkers of epileptogenic tissue. Considering the important role of interneuron activity in physiological HFO generation, we studied their modulation by midazolam (MDZ), an agonist of γ-aminobutyric acid type A (GABA)-benzodiazepine receptors. Here, we analyzed 80 intracranial electrode contacts in amygdala and hippocampus of 13 patients with drug-refractory focal epilepsy who had received MDZ for seizure termination during presurgical monitoring.

Anticancer Potential of Diruthenium Complexes with Bridging Hydrocarbyl Ligands from Bioactive Alkynols.

Diruthenacyclopentenone complexes of the general composition [RuCp(CO){μ-η:η-CH═C(C(OH)(R))C(═O)}] (-; Cp = η-CH) were synthesized in 94-96% yields from the reactions of [RuCp(CO){μ-η:η-C(Ph)═C(Ph)C(═O)}] () with 1-ethynylcyclopentanol, 17α-ethynylestradiol, and 17-ethynyltestosterone, respectively, in toluene at reflux. Protonation of - by HBF afforded the corresponding allenyl derivatives [RuCp(CO){μ-η:η-CH═C═R}]BF (-) in 85-93% yields. All products were thoroughly characterized by elemental analysis, mass spectrometry, and IR, UV-vis, and nuclear magnetic resonance spectroscopy.

New glycoconjugation strategies for Ruthenium(II) arene complexes via phosphane ligands and assessment of their antiproliferative activity.

Glycoconjugation is a powerful tool to improve the anticancer activity of metal complexes. Herein, we modified commercial arylphosphanes with carbohydrate-derived fragments for the preparation of novel glycoconjugated ruthenium(II) p-cymene complexes. Specifically, d-galactal and d-allal-derived vinyl epoxides (VEβ and VEα) were coupled with (2-hydroxyphenyl)diphenylphosphane, affording the 2,3-unsaturated glycophosphanes 1β and 1α.

Graphene oxide interaction with Lemna minor: Root barrier strong enough to prevent nanoblade-morphology-induced toxicity.

The production of graphene oxide (GO) along with its applications in various aquatic environments is vastly increasing thanks to its rapidly expanding range of new GO-based environmental technologies. Therefore, the fate of GO in aquatic environments is an important issue, as it could become an environmental challenge if its potential toxic mechanism is not addressed properly. Number of studies reporting the toxicity of GO to various aquatic organisms is still increasing.

Identification of potent anticancer copper(ii) complexes containing tripodal bis[2-ethyl-di(3,5-dialkyl-1H-pyrazol-1-yl)]amine moiety.

A series of heteroleptic copper(ii) complexes of the composition [Cu(L)Cl]X, where X = ClO and/or PF and [bis(2-ethyl-di(3,5-dimethyl-1H-pyrazol-1-yl))-(6-methyl-(2-pyridylmethyl))]amine (L), [bis(2-ethyl-di(3,5-dimethyl-1H-pyrazol-1-yl))-(3,4-dimethoxy-(2-pyridylmethyl))]amine (L), [bis(2-ethyl-di(3,5-dimethyl-1H-pyrazol-1-yl)-(2-quinolymethyl)]amine (L), [bis(2-ethyl-di(3,5-dimethyl-1H-pyrazolyl)-(di(3,5-dimethyl-1H-pyrazol-1-yl-methyl))]amine (L) and [bis(2-ethyl-di(3,5-dimethyl-1H-pyrazol-1-yl)-(5-methyl-3-phenyl-1H-pyrazol-1-yl-methyl)]amine (L), were prepared and thoroughly characterized including single-crystal X-ray diffraction technique. The in vitro cytotoxicity of complexes against A2780, A2780R, HOS and MCF-7 human cancer cell lines was evaluated using the MTT test. The results revealed that complexes [Cu(L)Cl]PF (1-PF), [Cu(L)Cl]ClO (2-ClO) and [Cu(L)Cl]PF (3-PF) are the most effective, with IC values ranging from 1.

Toxicity of Carbon Nanomaterials-Towards Reliable Viability Assessment via New Approach in Flow Cytometry.

The scope of application of carbon nanomaterials in biomedical, environmental and industrial fields is recently substantially increasing. Since in vitro toxicity testing is the first essential step for any commercial usage, it is crucial to have a reliable method to analyze the potentially harmful effects of carbon nanomaterials. Even though researchers already reported the interference of carbon nanomaterials with common toxicity assays, there is still, unfortunately, a large number of studies that neglect this fact.

Copper(II) Complexes Containing Natural Flavonoid Pomiferin Show Considerable In Vitro Cytotoxicity and Anti-inflammatory Effects.

A series of new heteroleptic copper(II) complexes of the composition [Cu(L)(bpy)]NO·2MeOH (), [Cu(L)(dimebpy)]NO·2HO (), [Cu(L)(phen)]NO·2MeOH (), [Cu(L)(bphen)]NO·MeOH (), [Cu(L)(dppz)]NO·MeOH () was prepared, where HL = 3-(3,4-dihydroxyphenyl)-5-hydroxy-8,8-dimethyl-6-(3-methylbut-2-ene-1-yl)-4,8-benzo[1,2-:3,4-']dipyran-4-one, (pomiferin) and bpy = 2,2'-bipyridine, dimebpy = 4,4'-dimethyl-2,2'-bipyridine, phen = 1,10-phenanthroline, bphen = 4,7-diphenyl-1,10-phenanthroline, and dppz = dipyrido[3,2-:2',3'-]phenazine. The complexes were characterized using elemental analysis, infrared and Uis spectroscopies, mass spectrometry, thermal analysis and conductivity measurements. The in vitro cytotoxicity, screened against eight human cancer cell lines (breast adenocarcinoma (MCF-7), osteosarcoma (HOS), lung adenocarcinoma (A549), prostate adenocarcinoma (PC-3), ovarian carcinoma (A2780), cisplatin-resistant ovarian carcinoma (A2780R), colorectal adenocarcinoma (Caco-2) and monocytic leukemia (THP-1), revealed the complexes as effective antiproliferative agents, with the IC values of 2.

Silver Covalently Bound to Cyanographene Overcomes Bacterial Resistance to Silver Nanoparticles and Antibiotics.

The ability of bacteria to develop resistance to antibiotics is threatening one of the pillars of modern medicine. It was recently understood that bacteria can develop resistance even to silver nanoparticles by starting to produce flagellin, a protein which induces their aggregation and deactivation. This study shows that silver covalently bound to cyanographene (GCN/Ag) kills silver-nanoparticle-resistant bacteria at concentrations 30 times lower than silver nanoparticles, a challenge which has been so far unmet.

Superradiance of bacteriochlorophyll c aggregates in chlorosomes of green photosynthetic bacteria.

Chlorosomes are the main light-harvesting complexes of green photosynthetic bacteria that are adapted to a phototrophic life at low-light conditions. They contain a large number of bacteriochlorophyll c, d, or e molecules organized in self-assembling aggregates. Tight packing of the pigments results in strong excitonic interactions between the monomers, which leads to a redshift of the absorption spectra and excitation delocalization.

Crucial cytotoxic and antimicrobial activity changes driven by amount of doped silver in biocompatible carbon nitride nanosheets.

The use of Ag-modified nanomaterials continues to attract attention in biological contamination control, their potential cytotoxicity is often overlooked. Herein, biocompatible carbon nitride is modified with 1 and 5 wt.% Ag and effects of different nanomaterial dose and Ag content on antimicrobial activity and cytotoxicity is studied.

The environmental fate of graphene oxide in aquatic environment-Complete mitigation of its acute toxicity to planktonic and benthic crustaceans by algae.

Graphene oxide (GO) as the most studied hydrophilic graphene derivative can be deployed in a broad spectrum of environmental technologies opening the issue of its ecotoxicity. Nevertheless, the information about its behavior in complex aquatic environment is still not sufficient. Here, we studied the interaction of three differently oxidized GO systems with planktonic and benthic crustaceans.

The Differential Effect of Carbon Dots on Gene Expression and DNA Methylation of Human Embryonic Lung Fibroblasts as a Function of Surface Charge and Dose.

This study presents a toxicological evaluation of two types of carbon dots (CD), similar in size (<10 nm) but differing in surface charge. Whole-genome mRNA and miRNA expression (RNAseq), as well as gene-specific DNA methylation changes, were analyzed in human embryonic lung fibroblasts (HEL 12469) after 4 h and 24 h exposure to concentrations of 10 and 50 µg/mL (for positive charged CD; pCD) or 10 and 100 µg/mL (for negative charged CD, nCD). The results showed a distinct response for the tested nanomaterials (NMs).

Extending knowledge of the clinical picture of Balkan adder (Vipera berus bosniensis) envenoming: The first photographically-documented neurotoxic case from South-Western Hungary.

We report a severe envenoming associated with minimal local symptoms following a Balkan adder (Vipera berus bosniensis) bite in South-Western Hungary. A 63-year-old male with a history of hypertension and sinus bradycardia (45/min) was bitten by a sub-adult specimen of V. b.

Oxygen uptake during Nordic walking training in patients rehabilitated after coronary events.

Background: Nordic walking (NW) is an effective form of endurance training in cardiac rehabilitation (CR). The key parameter for the safety and effectiveness of the training is its intensity. Training intensity may be directly measured by the volume of oxygen consumption (VO₂), and indirectly by chronotropic cardiac response to exercise.

Further clinical evidence for the existence of neurotoxicity in a population of the European adder (Vipera berus berus) in eastern Hungary: second authenticated case.

We report a recent case of common adder (Vipera berus) envenoming causing paralytic signs and symptoms. A 12-year-old girl was bitten by the nominate subspecies of the common adder (V. berus berus) in eastern Hungary on May 2, 2012, 22 km away from where the first neurotoxic V.