A proper diet is one of major factors contributing to good health and is directly related to general condition of the organism. Phenolic compounds are abundant in foods and beverages (fresh and processed fruits and vegetables, leguminous plants, cereals, herbs, spices, tea, coffee, wine, beer) and their pleiotropic biological activities result in numerous health beneficial effects. On the other hand, high reactivity and very large diversity in terms of structure and molecular weight renders polyphenols one of the most difficult groups of compounds to investigate, as evidenced by ambiguous and sometimes contradictory results of many studies. Furthermore, phenolics undergo metabolic transformations, which significantly change their biological activities. Here, we discuss some aspects of metabolism and absorption of phenolic compounds. On the basis of information reported in the literature as well as in summaries of clinical trials and patent applications, we also give an overview of strategies for enhancing their bioavailability.

Chemoprevention has recently gained a new dimension due to the possibility of studying the mechanisms of action of chemopreventive agents at the molecular level. Many compounds have been proved to inhibit early stages of carcinogenesis in experimental models. These compounds include both recognized drugs (such as tamoxifen and nonsteroidal anti-inflammatory drugs) and natural constituents of edible and therapeutic plants, particularly polyphenols. Phenolics are characterized by high structural diversity and, consequently, a very broad spectrum of biological activities. They are increasingly looked upon as a valuable alternative or a support for synthetic drugs, as evidenced by a growing number of clinical trials regarding the use of phenolic compounds and polyphenol-rich extracts in chemoprevention and therapy. In the present work, we discuss the effectiveness of natural polyphenols as cancer preventive and therapeutic agents resulting from their synergy with synthetic or semisynthetic anticancer drugs as well as with other phenolic compounds of plant origin.

Over 1.5 billion children from around the world were affected by school or university closures during the early phase of the COVID-19 pandemic in 2020 and distance learning was introduced for many pupils. The article presents the results of a survey conducted among Polish teachers of early education (N = 239), which aimed at answering an important question: To what extent and in what ways did Polish teachers cope with distance learning during the pandemic? The results of the survey revealed the many problems that teachers faced during 'remote education'. It was found, that in some cases: there was a lack of information technology equipment in the pupils' homes, a lack of communication with the pupils and their parents, a lack of motivation among pupils, and health problems had begun emerge amongst children. Nonetheless, teachers noted some positive aspects of this form of education, which enabled them to conduct classes during the pandemic. It was noted that many teachers indicated that the experience they had gained in remote working provided important indications for the further development of distance learning approaches with young children that may help to ameliorate the potential social inequalities that may arise in such a crisis situation.

Polyphenols are natural compounds of high structural diversity which translates into a very wide spectrum of biological activities, including chemoprevention. Here we report that a Japanese quince fruit flavanol preparation (JQFFP) caused favorable changes in Bax/Bcl-2 mRNA ratio, which rendered normal and cancer cells more resistant and more sensitive, respectively, to apoptosis. DU145 human prostate cancer cells were characterized by the most advantageous Bax/Bcl-2 ratio. The growth and invasiveness of MDA-MB-231 human breast cancer cells were strongly suppressed by JQFFP, which was accompanied with a decrease in MMP-9 activity and stimulation of TIMP-1 expression. Importantly, JQFFP did not decrease normal human prostate PNT1A cell number, whereas Bax/Bcl-2 ratio decreased which implies increased resistance to apoptosis. In conclusion, JQFFP exhibited a potent antiproliferative effect against cancer cells, inhibited their invasiveness, and decreased expression level of several genes involved in apoptosis, angiogenesis, and metastasis.

There is a growing interest in plant polyphenols (including flavanols) that exhibit pleiotropic biological activities such as antiinflammatory, antioxidant, and anticancer effects. Here, we report for the first time the inhibition of MDA-MB-231 breast cancer cell viability and invasiveness by an evening primrose flavanol preparation (EPFP). We observed a decrease in MDA-MB-231 viability of 50% vs. a control after 72 h of incubation with EPFP at a concentration of 58 μM gallic acid equivalents (GAE) and an inhibition of their invasiveness of 65% vs. a control at 75 μM GAE after 48 h of incubation. EPFP caused a 10-fold reduction in matrix metalloproteinase-9 (MMP-9) activity at 100 μM GAE. Furthermore, through modulation of mRNA expression, EPFP reduced the expression levels of the following proteins: antiapoptotic Bcl-2, angiogenic vascular endothelial growth factor (VEGF), and 2 transcription factors (c-Jun, c-Fos). Moreover, analysis by flow cytometry revealed that EPFP induced apoptosis in MDA-MB-231 cells. In conclusion, our data shows that EPFP inhibits cell viability by increasing apoptosis and decreases cell invasiveness by decreasing angiogenesis.