Oxo derivatives of pyrazolines and pyrazolidines are important heterocyclic compounds due to their unique biological activities and have been widely applied in pharmaceutical and agromedical fields. In this review, we provide an account of some recent advances in the field of pyrazolone chemistry, specifically on the reported synthesis methods of pyrazolinone (3-oxo-1, 2-dihydropyrazole) and 3, 5-pyrzolidinediones (3, 5-dioxotetrahydropyrazoles) derivatives.

This study was conducted to evaluate the effects of green fodders, fresh Sesbania sesban, and reed grass, on growth performance, blood metabolites, and meat quality of growing lambs. Twenty-one male Farafra lambs (19.0 ± 1.87 kg body weight) were randomly distributed into three groups, each with seven animals. The first group was fed on 60% concentrates and 40% fresh alfalfa, and served as a control. The second and third groups were fed also on 60% concentrates plus 40% fresh Sesbania sesban and reed grass, respectively. Lambs were fed the diets until reaching the target slaughter weight of about 50.0 kg, which was obtained after a period of 215 days. Five lambs from each group were randomly selected and slaughtered at the end of the experiment. Slaughter body weight, carcass traits weight, and dressing percentage were estimated. Chemical composition and physical properties of

Despite the toxicity of microplastics (MPs) in freshwater fish has been demonstrated in previous studies, their effects when mixed with other pollutants (organic and inorganic) are poorly understood. Thus, we aimed to test the hypothesis that the association of polyethylene MPs (PE-MPs) to a mix of emerging pollutants induces more adverse genotoxic, mutagenic, and redox unbalance effects in adult zebrafish (Danio rerio), after 15 days of exposure. Although the accumulation of MPs in animals was greater in animals exposed to PE-MPs alone, erythrocyte DNA damage (comet assay) and the frequency of erythrocytic nuclear abnormalities (ENAs) evidenced in zebrafish exposed to PE-MPs alone were as pronounced as those observed in animals exposed to the mix of pollutant (alone or in combination with MPs), which constitutes the big picture of the current study. Moreover, we noticed that such effects were associated with an imbalance between pro-and antioxidant metabolism in animals, whose activity of superoxide dismutase (SOD) and catalase (CAT) was assessed in different organs which were not sufficient to counterbalance the production of reactive oxygen species [hydrogen peroxide (H₂O₂)] and nitrogen [nitric oxide (NO)] evaluated. The principal component analysis (PCA) also revealed that while the antioxidant activity was more pronounced in the brain and liver of animals, the highest production of H₂O₂ was perceived in the gills and muscles, suggesting that the biochemical response of the animals was organ-dependent. Thus, the present study did not demonstrate antagonistic, synergistic, or additive effects on animals exposed to the combination between PE-MPs and a mix of pollutants in the zebrafish, which reinforces the theory that interactions between pollutants in aquatic ecosystems may be as complex as their effects on freshwater ichthyofauna.

There have been significant impacts of the current COVID-19 pandemic on society including high health and economic costs. However, little is known about the potential ecological risks of this virus despite its presence in freshwater systems. In this study, we aimed to evaluate the exposure of Poecilia reticulata juveniles to two peptides derived from Spike protein of SARS-CoV-2, which was synthesized in the laboratory (named PSPD-2002 and PSPD-2003). For this, the animals were exposed for 35 days to the peptides at a concentration of 40 µg/L and different toxicity biomarkers were assessed. Our data indicated that the peptides were able to induce anxiety-like behavior in the open field test and increased acetylcholinesterase (AChE) activity. The biometric evaluation also revealed that the animals exposed to the peptides displayed alterations in the pattern of growth/development. Furthermore, the increased activity of superoxide dismutase (SOD) and catalase (CAT) enzymes were accompanied by increased levels of malondialdehyde (MDA), reactive oxygen species (ROS) and hydrogen peroxide (H₂O₂), which suggests a redox imbalance induced by SARS-CoV-2 spike protein peptides. Moreover, molecular docking analysis suggested a strong interaction of the peptides with the enzymes AChE, SOD and CAT, allowing us to infer that the observed effects are related to the direct action of the peptides on the functionality of these enzymes. Consequently, our study provided evidence that the presence of SARS-CoV-2 viral particles in the freshwater ecosystems offer a health risk to fish and other aquatic organisms.