Environmental pollution by cadmium (Cd) is currently a common problem in many countries, especially in highly industrialised areas. Cd present in the soil can be absorbed by plants through the root system. The aim of the present study was to investigate the effects of cadmium on the metabolic activity of cucumber plants (Cucumis sativus L.) and the accumulation and distribution of Cd in the organs of the plants. Cucumber seeds (3 g) were exposed to 0.76, 1.58 or 4.17 mg Cd/L (applied as CdCl₂ solutions). The activity of selected antioxidant enzymes - glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT), lipid peroxidation and the content of photosynthetic pigments were determined in 6-week-old cucumber plants. In addition, intake of Cd has been determined by flame atomic absorption spectrometry (F-AAS). The results show that the applied cadmium concentrations affected the activity of antioxidant enzymes. An increase in CAT activity and a decrease in SOD activity were observed in all cucumber organs analysed. GSH-Px activity increased in the roots and stems. Surprisingly, GSH-Px activity decreased in the leaves. The level of lipid peroxidation was usually unchanged (the only one statistically significant change was a decrease in the concentration of malondialdehyde in the leaves which was observed after exposure to the highest Cd concentration). The applied Cd concentrations had no effect on the content of photosynthetic pigments. The highest cadmium content was found in the roots of cucumber plants. Cd tends to accumulate in the roots and a small amount was translocated to the stems and leaves, which was confirmed with the translocation factor (TF). The results indicate that the range of cadmium concentrations used, corresponding to the level of environmental pollution recorded in Europe, effectively activates the antioxidant enzyme system, without intensifying lipid peroxidation or reducing the content of photosynthetic pigments.

Normal oxygen metabolism is an endogenous source of reactive oxygen species (ROS). The source of ROS are also many environmental factors including heavy metals. In certain concentration range, the presence of ROS is necessary to maintain proper cell function. Thus, cells have many mechanisms, which role is focused on maintaining a constant concentration of ROS. Imbalance between the formation of ROS and action of a protective antioxidant system leads to oxidative stress. This may results with a damage to the structure of proteins, lipids and nucleic acids, which in turn can lead to disturbances in the functioning of the cell and even to the death. The aim of the study was to evaluate the effect of copper ions on the metabolic activity of garden cress Lepidium sativum L. The action of copper ions with different concentrations was treated seeds. After four, six and eight days after planting in the leaves of garden cress were determined the specific activity of guaiacol peroxidase (GPOX), lipid peroxidation and protein content. Additionally intake of copper ions was determined using adsorption spectrometry technique. The results revealed that the applied doses of copper ions affected the activity of guaiacol peroxidase. The highest enzyme activity was found in plant material, which was treated with dose of copper ions 1000 mg/dm³ regardless of day. In the same samples the lowest level of lipid peroxidation was found. The highest concentrations of total proteins was found in samples treated with the highest dose of copper ions. The copper content in the tested plant material is correlated with the applied dose of copper ions. Our results indicate reliable correlations between copper content and values of oxidative stress biomarkers in plant tissues.

During the coronavirus disease 2019 (COVID‑19) pandemic, cognitive impairment of varying degrees of severity began to be observed in a significant percentage of patients. The present study discussed the impact of immunological processes on structural and functional changes in the central nervous system and the related cognitive disorders. The purpose of the present review was to analyse and discuss available information from the scientific literature considering the possible relationship between severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) viral infection and cognitive impairment, including NeuroCOVID, frontal syndrome and cytokine storm. A systematic literature review was conducted using: Google Scholar, Elsevier and the PubMed database. When searching for materials, the following keywords were used: ‘cognitive dysfunctions’, ‘SARS‑CoV‑2’, ‘COVID‑19’, ‘Neuro‑SARS2’, ‘NeuroCOVID’, ‘frontal syndrome’, ‘cytokine storm’, ‘Long COVID‑19’. A total of 96 articles were included in the study. The analysis focused on the characteristics of each study's materials, methods, results and conclusions. SARS‑CoV‑2 infection may induce or influence existing cognitive disorders of various nature and severity. The influence of immunological factors related to the response against SARS‑CoV‑2 on the disturbance of cerebral perfusion, the functioning of nerve cells and the neuroprotective effect has been demonstrated. Particular importance is attached to the cytokine storm and the related difference between pro‑ and anti‑inflammatory effects, oxidative stress, disturbances in the regulation of the hypothalamic‑pituitary‑adrenal axis and the stress response of the body.

The SARS-CoV-2 spike receptor-binding motif is crucial for viral entry via interaction with the human ACE2 receptor. Mutations N501Y and E484K, found in several variants of concern, impact viral transmissibility and immune escape, but experimental data on their binding effects remain inconsistent. Using isothermal titration calorimetry (ITC) and molecular dynamics (MD) simulations, we analyzed the thermodynamic and structural effects of these mutations. ITC confirmed that N501Y increases ACE2 affinity by 2.2-fold, while E484K enhances binding by 5.8-fold. The Beta/Gamma variant (carrying both mutations) showed the strongest affinity, with a 15-fold increase. E484K was enthalpy-driven, while N501Y introduced entropy-driven effects, suggesting hydrophobic interactions and conformational changes. MD simulations revealed distinct binding poses, with Beta/Gamma peptides interacting with a secondary ACE2 site. A strong correlation was found between entropy contributions and hydrophobic contacts. Additionally, a convolutional neural network was used to estimate the free binding energy of these complexes. Our findings confirm that N501Y and E484K enhance ACE2 binding, with the greatest effect when combined, providing insights into SARS-CoV-2 variant evolution and potential therapeutic strategies.

As a heavy metal, cadmium has strongly toxic effects on plants and can induce oxidative stress. It is absorbed by the roots and transported to the stems and leaves. The aim of the study was to evaluate the effect of various concentrations of cadmium on the metabolic activity of Beta vulgaris and assess the dependence of these processes on the content of metal in the plants. To demonstrate the effect of cadmium on metabolism, protein and photosynthetic pigment content, lipid peroxidation, and the activity of enzymes specific for oxidative stress in roots and shoots were measured. Seeds of B. vulgaris were treated with different concentrations of Cd supplied via a CdCl₂ solution: 0 (control), 200, 300 and 400 mg/dm³. Results of the present study revealed increased GPOX activity as cadmium concentration rose, while SOD activity was stimulated by a low Cd concentration (200 mg/dm³) and reduced by high levels of Cd. Based on the present findings, it can be concluded that GPOX in B. vulgaris played a more important role in ROS scavenging than SOD did and was able to reduce the level of lipid peroxidation in plants. Cadmium, in the concentration range used, did not show any significant effect on protein or photosynthetic pigment content.