Unmodified magnetic nanoparticles (MNPs) lack antibacterial potential. We investigated MNPs surface modifications that can impart antibacterial activity. Six MNPs species were prepared and characterized. Their antibacterial and antibiofilm potentials, surface affinity, and cytotoxicity were evaluated. Prepared MNPs were functionalized with citric acid, amine group, amino-propyl trimethoxy silane (APTMS), arginine, or oleic acid (OA) to give hydrophilic and hydrophobic MNPs with surface charge ranging from −30 to +30 mV. Prepared MNPs were spherical in shape with an average size of 6-15 nm. Hydrophobic (OA-MNPs) and positively charged MNPs (APTMS-MNPs) had significant concentration dependent antibacterial effect. OA-MNPs showed higher inhibitory potential against S. aureus and E. coli (80%) than APTMS-MNPs (70%). Both particles exhibited surface affinity to S. aureus and E. coli. Different concentrations of OA-MNPs decreased S. aureus and E. coli biofilm formation by 50-90%, while APTMS-MNPs reduced it by 30-90%, respectively. Up to 90% of preformed biofilms of S. aureus and E. coli were destroyed by OAMNPs and APTMS-MNPs. In conclusion, surface positivity and hydrophobicity enhance antibacterial and antibiofilm properties of MNPs.

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Inactivation of rabies virus is essential for rabies vaccine preparation where the inactivating compound that is currently recommended for rabies vaccine preparation is β-propiolactone (β-PL). This compound is considered better than phenol and formalin but it is expensive and potentially carcinogenic. Data revealed that Ascorbic acid (AA) with cupric ions could yield complete and irreversible inactivation of rabies virus without adversely affecting its antigenicity. Additionally, the results of testing the vaccine potency with the selected inactivating compounds were comparable (P<0.05), and ED50 was higher than the recommended World Health Organization (WHO) limits. The use of HemaGel (plasma substitute) for testing vaccine stabilization was compared with the currently used vaccine stabilizers (human albumin and lactose). HemaGel yielded better stability than the other tested stabilizers. Monitoring of cellular and humoral immune responses indicated that both the total IgG level against rabies vaccine and the IFN and IL5 levels obtained with the HemaGel-stabilized vaccines were higher than those obtained with human albumin- and lactose-stabilized vaccine candidates.

Antimicrobial resistance (AMR) is a global public health threat resulting in high mortality rates. Current study aimed to identify the most prevalent pathogens among variable infection sites and their AMR pattern. Data concerning cultures and antibiotic susceptibilities were retrieved from Microbiology Department's records and statistically analyzed. Out of 554 bacterial isolates, Gram negative isolates (68.4%) were predominant. Urine specimens showed the highest incidence of recovery of total isolates (41.5%, n=230) followed by blood (23.1%, n=128), while sputum specimens exhibited the least frequency (17%, n=94). E. coli (30.7%, n=170), S. aureus (21.1%, n=117) and Klebsiella spp (20.9%, n=116) were the most frequently isolated pathogens. Recovery of isolates was significantly more frequent among males (P<0.05) except in case of urine specimens. Highest incidence of resistance in both Gram positive and Gram negative isolates was recorded in case of cephalosporins and penicillin/β-lactamase. Gram positive isolates exhibited the least resistance to linezolid (10.8%) and vancomycin (9.5%) whereas colistin was the most effective against Gram negative isolates as it recorded 16.4% resistance. Higher frequency of multiple drug resistance (MDR) was also observed in Gram negative isolates compared to Gram positive ones. Resistance to uropathogens and MDR were significantly more frequent in males. Although E. coli was the most prevalent uropathogen but it showed the least incidence of MDR however Pseudomonas spp exhibited the highest MDR rate. The high incidence of resistance in the current study is alarming and highlights the necessity of routinely monitoring the local prevalence of resistance for selecting the best antimicrobial treatment and as a guide for empirical therapy.