Ultra-small gold nanoparticles (Au-NPs) “≤ 10 nm diameters” have potent biomedical applications. Hence, the present study aimed to greenly synthesize ultra-small gold nanoparticles using Egyptian propolis extract. Different biological activities, in vivo bio-distribution and acute toxicity study were assessed. Results revealed that, Egyptian propolis extract can successfully synthesize the highly pure and stable ultra-small Au-NPs with average diameter 7.8 nm. In vitro antimicrobial and antimycobacterial activities revealed the powerful effect of the prepared Au-NPs. Moreover, the cytotoxic effect on human cancer cell lines revealed the potent inhibition of the cancer cells’ proliferation with high reactive oxygen species-mediated apoptosis induction. In vivo bio-distribution and acute toxicity studies were performed (10 and 100 mg/kg doses) in male albino rats. The ultra-small Au-NPs showed low or no toxicity upon using the Au-NPs low dose. The mean area accumulation (%) of the Au-NPs was higher in the liver, kidney, and brain tissues (4.41, 2.96, and 0.3 times, respectively) treated with high Au-NPs dosage compared to those treated with the low dose. Surprisingly, Au-NP accumulation in brain tissue was observed in the glial cells only. Accordingly, the low dose (10 mg/kg) of Au-NPs can be used safely in a variety of biomedical applications.

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In the last few years, many efforts have been devoted to investigating the antibacterial activity of metal nanoparticles, especially against multidrug-resistant bacteria. Recently extensively drug-resistant (XDR) bacteria have emerged and caused a global threat. The purpose of this manuscript was to synthesize nanostructured γ-Al2O3 as an antibacterial agent against some XDRs. The results showed that Al2O3 was a mix of rod and spherical shapes in the nano range with diameters of less than 30 nm. The zeta potential was determined to estimate the surface charge for the synthesized γ-Al2O3, which was recorded as −34 ± 1.8 mV, indicating good stability. The synthesized nanostructured γ-Al2O3 showed a potent antibacterial activity against extensively drug-resistant Acinetobacter baumanii, with an inhibition zone diameter that reached 19 mm and a minimum inhibitory concentration (MIC) value that reached 2 µg/mL. The observed antibacterial activity of the prepared Al2O3 nanoparticles confirmed that the main mechanistic actions include bacterial cells apoptosis, ROS increment, cellular membrane disruption, and DNA damage. The cytotoxic effect (CC50) of the prepared γ-Al2O3-NPs was 1250 µg/mL in a normal human lung fibroblast cell line (WI-38 cells). It can be concluded that the synthesized γ-Al2O3 had an acceptable toxicity, which may pave the way for its use as a potent agent in the fight against XDR bacteria.

Background: Helicobacter pylori (H. pylori), especially the strains expressing cytotoxin-associated gene A (CagA), besides causing gastric diseases, may also involve other systems including the reproductive system leading to infertility. In males, antibodies produced against H. pylori flagella may cross react with spermatozoa flagella; due to antigenic mimicry between them. Infected males have decreased sperm count, motility and viability, reduced numbers of normally shaped sperms and augmented systemic levels of inflammatory cytokines. Objective(s): to detect H. pylori-related infertility prevalence among males; and to address the possibility that such infection may play a detrimental role in their semen quality. Methods: One hundred infertile male patients attending a private hospital in Alexandria were screened for H. pylori by enzyme linked immunosorbent assay (ELISA). CagA strains were further identified using CagA IgG ELISA. Semen analysis was performed to assess semen quality as regards sperm count, motility, vitality and morphology. Results: H. pylori seropositivity was 73% (73 out of 100) among screened cases. Sixty out of the 73 positive cases for H. pylori IgG (82.19%) were CagA strains. H. pylori prevalence was significantly higher among the group of patients with idiopathic infertility (79.7%) than among those who had one or more diagnosed causes of infertility; p value= 0.024. CagA status significantly influenced the quality of semen among infected cases compared to uninfected ones. (p value<0.001). Conclusion: H. pylori infection; specially by CagA strains can be responsible for cases of idiopathic infertility in males through its negative effect on semen quality.