Nanotechnology can offer a number of options against coronavirus disease 2019 (COVID‐19) acting both extracellularly and intracellularly to the host cells. Here, the aim is to explore graphene oxide (GO), the most studied 2D nanomaterial in biomedical applications, as a nanoscale platform for interaction with SARS‐CoV‐2. Molecular docking analyses of GO sheets on interaction with three different structures: SARS‐CoV‐2 viral spike (open state – 6VYB or closed state – 6VXX), ACE2 (1R42), and the ACE2‐bound spike complex (6M0J) are performed. GO shows high affinity for the surface of all three structures (6M0J, 6VYB and 6VXX). When binding affinities and involved bonding types are compared, GO interacts more strongly with the spike or ACE2, compared to 6M0J. Infection experiments using infectious viral particles from four different clades as classified by Global Initiative on Sharing all Influenza Data (GISAID), are performed for validation purposes. Thin, biological‐grade GO nanoscale (few hundred nanometers in lateral dimension) sheets are able to significantly reduce copies for three different viral clades. This data has demonstrated that GO sheets have the capacity to interact with SARS‐CoV‐2 surface components and disrupt infectivity even in the presence of any mutations on the viral spike. GO nanosheets are proposed to be further explored as a nanoscale platform for development of antiviral strategies against COVID‐19.

The aim of this study is to investigate the effect of propolis, which may have estrogenic effects, on myocardial ischemia/reperfusion (mI/R) injury not only in male rats but also in intact and ovariectomized (ovx) female rats. Six groups were formed: untreated males (n = 8), treated males (n = 9), untreated intact females (n = 9), treated intact females (n = 10), untreated ovx females (n = 10), and treated ovx females (n = 8).An alcoholic extract of a single dose of propolis (200 mg/kg) was administered orally daily for 14 days. Thirty minutes of ischemia and 120 min of reperfusion were performed. Blood pressure, heart rate, arrhythmias (ventricular premature contraction[VPC], ventricular tachycardia [VT], ventricular fibrillation [VF]), and myocardial infarct size were evaluated. Total antioxidant status (TAS), total oxidant status (TOS), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and 17 beta-estradiol (E2) were measured. The untreated females showed more resistance to mI/R injury than the untreated males, as evidenced by lower duration, incidence, and score of arrhythmias, and smaller infarct size (p < .05). After ovx, this resistance disappeared. Propolis improved these values in treated males and treated ovx females (p < .05). Propolis increased TAS in treated males and decreased TOS in treated ovx females as well as elevated SOD in all treated groups (p < .05). Propolis decreased E2 level in treated intact females; however, it increased E2 level in treated ovx females (p < .05). The results revealed that propolis could protect the heart against mI/R injury in males and ovx females. Practical applicationsIt is known that the female heart has an increased sensitivity to myocardial ischemia/ reperfusion (mI/R) injury due to estrogen deficiency and/or estrogen deprivation following menopause or surgical removal of the ovaries. Propolis has the potential to mimic estrogen under physiological and pathophysiological conditions, as well as its antioxidant property. The results indicated that propolis decreased myocardial infarct size, arrhythmia score, arrhythmia duration, and incidence in ovariectomized female rats and male rats. In addition, the present results demonstrated that an alcoholic

Background: Osteosarcoma; is one of the most common malignant tumors. Nowadays, because of the many side effects of cancer drugs, the usage of herbal medicine which can inhibit or eliminate cancer cells by their antioxidant compounds is increased. Objectives: In the present study anticancer effect of Tilia dasystyla and Polygonatum orientale Desf different extracts on osteogenic sarcoma (Saos-2) cancer cell line was investigated and their polyphenolic compounds were identified by liquid chromatographymass spectrometry (LC-MS) analysis. The cytotoxic effect of these extracts on Saos-2 cell line and identification of their phenolic compounds have not been reported so far. Methods: Cancer cell lines were provided from Department of Biological Sciences, Bursa University, Turkey. Different concentrations of the methanol, ethanol, and diluted water extracts (0.5-5 mg/mL) were tested on Saos-2 cell line. After 24, 48, and 72 hours, the cell viability was evaluated using 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. For the investigation of total phenolic compounds of T. dasystyla and P. orientale Desf extracts LC-MS method was applied. Results: According to the results diluted water extracts on the Saos-2 cancer cell line showed more cytotoxic effect than other solvents. The lowest IC50 value was 0.58 ± 0.01 mg/mL within 72 hours belonged to T. dasystyla water extract. Conclusions: Tilia dasystyla and Polygonatum orientale Desf extracts contain some polyphenolic compounds which showed cytotoxic effect on Saos-2 cancer cell line. The full potential of these herbal extracts is yet to be realized by further studies on animal models and subsequent trials.

In article number 2101483, Kostas Kostarelos, Açelya Yilmazer, and co‐workers report that thin, biological‐grade graphene oxide (GO) nanosheets show molecular affinity toward the SARS‐CoV‐2 viral spike and the ACE2‐bound spike complex. GO nanosheets were shown to inhibit the infection of wild‐type SARS‐CoV‐2 experimentally in cell cultures. Through an interplay of molecular dynamics simulations and cell biology, this work demonstrates that graphene oxide sheets could offer a platform to effectively interact and potentially transport other molecules to inactivate SARS‐CoV‐2.