Factors influencing the antimicrobial mechanism of chitosan action and its derivatives: A review.

Chitosan, a versatile amino polysaccharide biopolymer derived from chitin, exhibits broad-spectrum antimicrobial activity against various pathogenic microorganisms, including gram-negative and gram-positive bacteria, as well as fungi. Due to its ubiquitous use in medications, food, cosmetics, chemicals, and crops, it is an effective antibacterial agent. However, the antimicrobial performance of chitosan is influenced by multiple factors, which have been extensively investigated and reported in the literature.

Vancomycin and nisin-modified magnetic FeO@SiO nanostructures coated with chitosan to enhance antibacterial efficiency against methicillin resistant Staphylococcus aureus (MRSA) infection in a murine superficial wound model.

Background: The objective of this research was to prepare some FeO@SiO@Chitosan (CS) magnetic nanocomposites coupled with nisin, and vancomycin to evaluate their antibacterial efficacy under both in vitro and in vivo against the methicillin-resistant Staphylococcus. aureus (MRSA).

Methods: In this survey, the FeO@SiO magnetic nanoparticles (MNPs) were constructed as a core and covered the surface of MNPs via crosslinking CS by glutaraldehyde as a shell, then functionalized with vancomycin and nisin to enhance the inhibitory effects of nanoparticles (NPs).

Molecular epidemiology and collaboration of siderophore-based iron acquisition with surface adhesion in hypervirulent Pseudomonas aeruginosa isolates from wound infections.

Iron/siderophore uptake may play an important role in the biofilm formation and secretion of extracellular proteins in Pseudomonas aeruginosa isolates. In the present study, the role of siderophores, heme, and iron regulatory genes in the virulence of Pseudomonas aeruginosa isolates collected from wound infection was investigated. Three hundred eighty-four (384) swab samples were collected from wound infection and identified by phenotypic methods.

Prevalence and distribution of resistance and enterotoxins/enterotoxin-like genes in different clinical isolates of coagulase-negative Staphylococcus.

Background: Coagulase-negative staphylococcus (CoNS) is considered to be the major reservoirs for genes facilitating the evolution of S. aureus as a successful pathogen. The present study aimed to determine the occurrence of genes conferring resistance to fluoroquinolone, determining of the prevalence of insertion sequence elements IS256, IS257 and different superantigens (SAgs) among CoNS isolates obtained from various clinical sources.

Identification of hemolysin encoding genes and their association with antimicrobial resistance pattern among clinical isolates of coagulase-negative Staphylococci.

Objective: Coagulase-negative staphylococci (CoNS) are as considered opportunistic pathogens which capable of producing several toxins, enzymes and resistance genes. The current study aimed to determine the occurrence of different hemolysins genes and patterns of antibiotic resistance among CoNS species.

Results: The highest frequency of antibiotic resistance was observed against cefoxitin in 49 isolates (53.

Correlation between Infective Factors and Antibiotic Resistance in Clinical Isolates in West of Iran.

The present study was done to scrutinize the possible relation between infective genes and antimicrobial resistance in and . Considering the fact that the presence of recognized infective determinants among clinical isolates may promote the emergence of infections and persistence of in hospital settings, which can lead to an increase in antimicrobial resistance. 175 and 67 isolated from clinical specimens were used.

Prevalence of Virulence Factors and Vancomycin-resistant Genes among Enterococcus faecalis and E. faecium Isolated from Clinical Specimens.

Background: The aim of this study was to determine the occurrence of virulence determinants and vancomycin-resistant genes among Enterococcus faecalis and E. faecium obtained from various clinical sources.

Methods: The study was performed on the 280 enterococcal isolated from clinical specimens in Hamadan hospitals, western Iran in 2012-14.

Survey of strain distribution and antibiotic resistance pattern of group B streptococci (Streptococcus agalactiae) isolated from clinical specimens.

Aim: The aims of the present study were to determine the antibiotic susceptibility profils with particular emphasis on susceptible or resistant strains to macrolides and lincosamids antibiotics and to determine possible antibiotic resistance mechanisms occurring in group B streptococci (GBS) strains using PCR assay and disk diffusion method.

Methods: A total of 62 clinical GBS strains were investigated. Antibacterial susceptibility testing was performed using the disk diffusion method and inducible resistance test for clindamycin by standard double disk diffusion or D-zone test for all isolates to differentiate macrolide resistance phenotype (M), constitutive macrolide-lincosamide-streptogramin B phenotype (cMLSB) and induced macrolide-lincosamide-streptogramin B phenotype (iMLSB).