Amphotericin B (AmB) is a lifesaving antibiotic used to treat deep-seated mycotic infections. Both the pharmaceutical activity and highly toxic side effects of the drug rely on its interaction with biomembranes, which is governed by the molecular organization of AmB. In the present work, we present a detailed analysis of self-assembly of AmB molecules in different environments, interesting from the physiological standpoint, based on molecular spectroscopy techniques: electronic absorption, circular dichroism, steady state and time-resolved fluorescence and molecular dynamic calculations. The results show that, in the water medium, AmB self-associates to dimeric structures, referred to as "parallel" and "antiparallel". AmB dimers can further assemble into tetramers which can play a role of transmembrane ion channels, affecting electrophysiological homeostasis of a living cell. Understanding structural determinants of self-assembly of AmB opens a way to engineering preparations of the drug which retain pharmaceutical effectiveness under reduced toxicity.

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The aim of the study was to analyze how per os application of hydrocolloids of silver nanoparticles (22 nm) and lipid-coated silver nanoparticles (5 nm) affect the immune, redox, and lipid status of the blood of broiler chickens. The experiment was conducted on 60 chickens. The first group was the control (Group C). The chickens in Group II received a silver nanoparticle hydrocolloid (Ag-nano) at a dose of 5 mg/kg body weight (BW) per day. The chickens in Group III received a lipid-coated silver nanoparticle hydrocolloid (AgLnano) at a dose of 5 mg/kg BW per day. Blood for analysis was collected from 24-and 38-day-old chickens and several blood parameters were determined. The increase in phagocytosis and in the metabolic activity of leukocytes observed following per os administration of chemically synthesized silver nanoparticles differing in size and in the presence or absence of a lipid coating may indicate a developing inflammatory state in the organism. The decrease in haemoglobin content and antioxidant enzyme activity and the increase in the content of iron, bilirubin, and lipid peroxidation products are indicative of oxidative stress, although in the case of administration of AgL-nano the oxidation effect appears to be greater. Administration of silver nanoparticles to the chickens, particularly 5 nm lipid-coated nanoparticles, probably led to a disturbance in protein catabolism in the organism, which is evidenced by the decrease in the activity of the liver enzymes AST and ALT and the decreased concentration of the main protein metabolism products (creatinine and urea).

The aim of the study was to evaluate the effects of a diet containing different levels of Cu in two different chemical forms (carbonate and nanoparticles) on redox reactions and epigenetic changes in a rat model. For 4 weeks, five experimental groups (eight rats in each) were fed diets with two dosages of added Cu (standard—6.5 mg/kg or half of the standard dosage—3.25 mg/kg, and as a negative control no additional Cu in the mineral mixture) in two forms (standard—CuCO3 and copper nanoparticles). Addition of Cu nanoparticles resulted in higher Cp (ceruloplasmin) activity and LOOH (lipid peroxides) and MDA (malondialdehyde) content, as well as decrease the CAT (catalase) activity and level of PC (protein carbonyl), 3‐NT (3‐nitrotyrosine), 8‐OHdG (8‐hydroxydeoxyguanosine), GSH + GSSG (total glutathione) and DNA methylation. Reducing the dose of copper resulted in a decrease in the level of LOOH and GSH + GSSG as well as CAT activity, but increased the level of PC and methylated DNA. Based on these evidence, we concluded that addition of copper nanoparticles in the diet reduces protein oxidation and nitration as well as DNA oxidation and methylation. Lowering the level of Cu in the diet increases the oxidation of proteins and DNA methylation.

The aim of the study was to analyse how per os application of hydrocolloids of silver nanoparticles (22 nm) and lipid-coated nanosilver hydrocolloids (5 nm) affect the microbiological status and morphology of the jejunum of broiler chickens and their growth performance. The experiment was conducted on 60 chickens. The first group was the control. The chickens in group II received a silver nanoparticle hydrocolloid (ag-nano) at a dose of 5 mg/kg b.w./day. The chickens in group iii received a lipid-coated nanosilver hydrocolloid (agl-nano) at a dose of 5 mg/kg b.w./day. samples of digesta were taken from the jejunum during dissection and the total numbers of fungi, aerobic bacteria and bacteria of the coli group were determined in the samples. samples of the jejunum were also collected during dissection to determine the length of the villi and depth of the crypts. The silver nanoparticles had no effect on growth performance or the histological picture of the jejunum. an increase was noted in the total number of aerobic mesophilic bacteria and a decrease in the number of coli group bacteria, which are facultative anaerobes, which indicates that the nanosilver had a selective effect on the microflora of the digestive tract in the chickens.