No abstract

Hand hygiene is considered to be the key factor in controlling and preventing infection, either in hospital care settings or in the community. Alcohol-based hand sanitizers are commonly used due to their rapid action and broad spectrum of microbicidal activity, offering protection against bacteria and viruses. However, their frequent administration during COVID-19 pandemic was associated with serious hazards, such as skin toxicity, including irritation, skin dermatitis, skin dryness or cracking, along with peeling redness or itching, with the higher possibility of getting infections. Thus, there is a need to find alternative and novel approaches for hand sanitation. In our previous publications, we reported that rhamnolipids nano-micelles had a comparable antibacterial activity to alcohol-based hand sanitizer and a lower cytotoxicity against human dermal fibroblast cells. In the current study, we investigated the antiviral activity of rhamnolipids nano-micelles against SARS-CoV-2. There was no cytotoxic effect on Vero cells noted at the tested concentrations of rhamnolipids nano-micelles. The rhamnolipids nano-micelles solution at 20, 78, and 312 µg/mL all demonstrated a significant (p < 0.05) decrease of virus infectivity compared to the virus only and the blank vehicle sample. In addition, an acute irritation test was performed on rabbits to further ascertain the biosafety of rhamnolipids nano-micelles. In the eye and skin irritation tests, no degree of irritation was recorded after topical application of rhamnolipids nano-micelles. In addition, histopathological, biomarker, and hematological analyses from animals treated with rhamnolipids nano-micelles were identical to those recorded for untreated animal. From the above, we can conclude that rhamnolipids nano-micelles are a good candidate to be used as a hand sanitizer instead of alcohol-based hand sanitizers. However, they must still be tested in the future among healthcare workers (HCW) in a health care setting to ascertain their antimicrobial efficacy and safety compared to alcohol-based hand sanitizers.

Hand hygiene is the key factor to control and prevent the spread of infections, for example, hospital-acquired infections (HAIs). People commonly use alcohol-based hand sanitizers to assure hand hygiene. However, frequent use of alcohol-based hand sanitizers in a pandemic situation (e.g., COVID-19) was associated with serious drawbacks such as skin toxicity including irritation, skin dermatitis, and skin dryness or cracking, along with peeling, redness, or itching with higher possibility of infection. This demands the development of alternative novel products that are effective as alcohol-based hand sanitizers but have no hazardous effects. Zinc oxide nanoparticles (ZnO-NPs) are known to have broad-spectrum antimicrobial activity, be compatible with the biological system and the environment, and have applicable and economic industrial-scale production. Thus, ZnO-NPs might be a good candidate for hand sanitation. To the best of our knowledge, the antibacterial activity of ZnO-NPs in comparison to alcohol-based hand sanitizers has not yet been studied. In the present work, a comparative study of the antibacterial activity of ZnO-NPs vs. Sterillium, a commercial alcohol-based hand sanitizer that is commonly used in Egyptian hospitals, was performed against common microorganisms known to cause HAIs in Egypt, including Acinetobacter baumannii, Klebsiella pneumoniae, Methicillin-resistant Staphylococcus aureus (MRSA), and Staphylococcus aureus. The safety profiles of ZnO-NPs and Sterillium were also assessed. The obtained results demonstrated the superior antibacterial activity and safety of ZnO-NPs compared to Sterillium. Therefore, ZnO-NPs could be a promising candidate for hand sanitation in comparison to alcohol-based hand sanitizers; however, several studies related to long-term toxicity and stability of ZnO-NPs and investigations into their antimicrobial activity and safety in healthcare settings are still required in the future to ascertain their antimicrobial activity and safety.

The endocannabinoid system is participated in the pathogenesis of liver fibrosis. Activation of cannabinoid receptor type 2 (CB2) plays a principle role in liver regeneration and protection against liver injury. This study aimed to explore the role of CB2 agonist (AM1241) on suppressing the progress of liver fibrosis induced by bile duct ligation (BDL). AM1241 was administrated to BDL rats in two doses (3 and 6 mg/kg). Liver function and oxidative stress markers, hepatic TNF-α, IL-6 and IL-10, RT-qPCR expression of TLR4 gene, immunohistochemical expression of CD31, CD34, α-SMA and NF-κB as well as histopathology of liver tissue were all assessed. BDL rats (n=9) showed; significant (P<0.05) increase in aminotransferases activity, bilirubin levels, hepatic MDA, TNF-α and IL-6 levels and TLR4 gene-expression with significant decrease in GSH content and IL-10, marked histological fibrosis, pseudolobulation and cholangiolar proliferation with increased immune-expression of CD31, α-SMA and NF-κB with nil expression of CD34. Conversely, AM1241 administration at both doses significantly (P<0.05) ameliorated liver function markers, MDA level, pro-inflammatory cytokines TNF-α and IL-6 and TLR4 gene expression. Additionally, AM1241 significantly (P<0.05) increased GSH content and immunomodulatory cytokine; IL-10. Histologically, AM1241 limited fibroplasia extension, decreased cholongiocytes proliferation, and decreased immune-expression of CD31, α-SMA and NF-κB with strongly expressed CD34. The current study depicts that; CB2 receptors activation promotes liver regeneration and suppresses the progress of liver fibrosis through featured mechanisms including; TLR4/NF-κB pathway-dependent inhibition, suppressing pro-inflammatory cytokines; IL-6 and TNF-α, reducing angiogenesis and stimulating hepatic oval/progenitor cells.