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Introduction: Despite years of efforts to develop new antibiotics for eradicating multidrug-resistant (MDR) and multi-virulent Methicillin-Resistant Staphylococcus aureus (MRSA) and Vancomycin-Resistant Staphylococcus aureus (VRSA) infections, treatment failures and poor prognoses in most cases have been common. Therefore, there is an urgent need for new therapeutic approaches targeting virulence arrays. Our aim is to discover new anti-virulence therapies targeting MRSA and VRSA virulence arrays. Methodology: We employed phenotypic, molecular docking, and genetic studies to screen for anti-virulence activities among selected promising compounds: Coumarin, Simvastatin, and Ibuprofen. Results: We found that nearly all detected MRSA and VRSA strains exhibited MDR and multi-virulent profiles. The molecular docking results aligned with the phenotypic and genetic assessments of virulence production. Biofilm and hemolysin productions were inhibited, and all virulence genes were downregulated upon treatment with sub-minimum inhibitory concentration (sub-MIC) of these promising compounds. Ibuprofen was the most active compound, exhibiting the highest inhibition and downregulation of virulence gene products. Moreover, in vivo and histopathological studies confirmed these results. Interestingly, we observed a significant decrease in wound area and improvements in re-epithelialization and tissue organization in the Ibuprofen and antimicrobial treated group compared with the group treated with antimicrobial alone. These findings support the idea that a combination of Ibuprofen and antimicrobial drugs may offer a promising new therapy for MRSA and VRSA infections. Conclusion: We hope that our findings can be implemented in clinical practice to assist physicians in making the most suitable treatment decisions. [ABSTRACT FROM AUTHOR]

Over the past few decades, the production of metal oxide nanoparticles (MONPs) has developed into an exciting and sophisticated research area. Green metal oxide nanoparticles have played an extremely imperative role in various fields, including biomedical, environmental, energy, agricultural applications, catalytic, bioactive, antibacterial, poisonous, and biocompatible. To achieve sustainability and adopt environmentally friendly practices, the production of MONPs is now increasingly focused on exploring green chemistry and alternative pathways. When made using green synthesis techniques, the metal oxide nanoparticles are especially important because they do not require external stabilizers, capping agents, dangerous chemicals, or harsh operating conditions (high pressure and temperature). Plant-mediated synthesis of different MONPs using either whole cells or extracts has several advantages, including rapid synthesis (compared with other biogenic processes (using fungi and bacteria)), being more stable than other types, being available in nature, and being non-toxic. This review provides a comprehensive overview of the green synthesis of MONPs using plant parts, factors affecting the synthesis, and the characterization of synthesized NPs. Additionally, it highlights the potential of these environmentally friendly nanoparticles that are widely used to treat environmental pollutants, including the removal of heavy metals, antibacterials, and the degradation of organic pollutants. [ABSTRACT FROM AUTHOR]

Introduction: There is an urgent need to develop therapeutic options for biofilm-producing Staphylococcus aureus (S. aureus). Therefore, the renewed interest in essential oils (EOs), especially carvacrol, linalool and eugenol, has attracted the attention of our research group. Methods: Multidrug resistance and multivirulence profiles in addition to biofilm production of S. aureus strains isolated from cows with mastitis were evaluated using both phenotypic and genotypic methods. The antimicrobial and antibiofilm activities of EOs were tested using both in vitro and molecular docking studies. Moreover, the interactions between commonly used antibiotics and the tested EOs were detected using the checkerboard method. Results: We found that all our isolates (n= 37) were biofilm methicillin resistant S. aureus (MRSA) producers and 40.5% were vancomycin resistant S. aureus (VRSA). Unfortunately, 73 and 43.2% of the recovered MRSA isolates showed multidrug resistant (MDR) and multivirulence patterns, respectively. The antimicrobial activities of the tested EOs matched with the phenotypic evaluation of the antibiofilm activities and molecular docking studies. Linalool showed the highest antimicrobial and antibiofilm activities, followed by carvacrol and eugenol EOs. Fortunately, synergistic interactions between the investigated EOs and methicillin or vancomycin were detected with fractional inhibitory concentration index (FICI) values = 0.5. Moreover, the antimicrobial resistance patterns of 13 isolates changed to sensitive phenotypes after treatment with any of the investigated EOs. Treatment failure of bovine mastitis with resistant S. aureus can be avoided by combining the investigated EOs with available antimicrobial drugs. Conclusion: We hope that our findings can be translated into a formulation of new pharmaceutical dosage forms against biofilm-producing S. aureus pathogens. [ABSTRACT FROM AUTHOR]

Heavy metal toxicity is an important issue owing to its harmful influence on fish. Hence, this study is a pioneer attempt to verify the in vitro and in vivo efficacy of a magnetite (Fe3O4) nanogel (MNG) in mitigating waterborne lead (Pb) toxicity in African catfish. Fish (n = 160) were assigned into four groups for 45 days. The first (control) and second (MNG) groups were exposed to 0 and 1.2 mg L−1 of MNG in water. The third (Pb) and fourth (MNG + Pb) groups were exposed to 0 and 1.2 mg L−1 of MNG in water and 69.30 mg L−1 of Pb. In vitro, the MNG caused a dramatic drop in the Pb level within 120 h. The Pb-exposed group showed the lowest survival (57.5%) among the groups, with substantial elevations in hepato-renal function and lipid peroxide (MDA). Moreover, Pb exposure caused a remarkable decline in the protein-immune parameters and hepatic antioxidants, along with higher Pb residual deposition in muscles and obvious histopathological changes in the liver and kidney. Interestingly, adding aqueous MNG to Pb-exposed fish relieved these alterations and increased survivability. Thus, MNG is a novel antitoxic agent against Pb toxicity to maintain the health of C. gariepinus. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effects of dietary supplementation with nano-curcumin (NCur) and a nano-curcumin/chitosan blend (NCur/Ch) on growth performance, digestibility, immune response, antioxidant status, intestinal morphometric characters, and gene regulation in Nile tilapia. Fish (n = 180, initial body weight = 12.0 ± 0.53 g) received supplementary NCur at rates of 0 (control), 0.00625, and 0.0125, and NCur/Ch at rates of 0.00625 + 0.5 g/kg diet for 4 weeks. Growth performance parameters (final weight and length, body mass gain, specific growth, and length gain rates) were markedly increased, and the feed conversion ratio was significantly decreased in the NCur- and NCur/Ch-supplemented groups. Digestive enzyme (amylase), immune response markers (immunoglobulin M, nitrous oxide, and lysozyme activity), plasma albumin, and total protein were increased significantly, mainly with a diet supplemented with 0.00625 g NCur/kg. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), glucose, and cortisol levels decreased in the supplemented groups compared to the control. Significantly increased glutathione peroxidase (GPx) and decreased malondialdehyde (MDA) levels were observed in the NCur/Ch group. Superoxide dismutase (SOD) activity was improved in the 0.0125 NCur group. Intestinal morphometric characters, including villus length, width, interspace, and goblet cell abundance, were increased to cope with improved growth performance and were associated with upregulation of insulin-like growth factor 1 (igf-1) and complement C-5 (cc5) compared to the control group. Therefore, NCur and an NCur/Ch blend could be supplemented in the Nile tilapia diets as a natural alternative to promote growth, digestion, immune status, liver function, antioxidant status, and related gene expression in O. niloticus. [ABSTRACT FROM AUTHOR]