Microbiology
Abdolmajid Ghasemian; Shahin Najar Peerayeh; Bita Bakhshi; Mohsen Mirzaee
Abstract
Background:Isolates of Staphylococcus aureus express a myriad of adhesive surface proteins that play important role in colonization of the bacteria on nasal and skin surfaces, beginning the process of pathogenesis. The aim of this study was to screen several of the Microbial Surface Components Recognizing ...
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Background:Isolates of Staphylococcus aureus express a myriad of adhesive surface proteins that play important role in colonization of the bacteria on nasal and skin surfaces, beginning the process of pathogenesis. The aim of this study was to screen several of the Microbial Surface Components Recognizing Adhesive Matrix Molecules (MSCRAMMs) genes among the isolate of S. aureus from hospitalized children.
Methods:A totalof 22 S. aureus isolates were collected from hospitalized children in Tehran from 2012 to 2013. Detection of the mecA and several adhesive surface proteins genes including clfA, B (encoding clumping factors A, B); fnbA, B (encoding finronectin binding proteins A, B); fib (encoding fibrinogen binding protein); eno (encoding laminin binding protein); cna (encoding collagen binding protein); ebps (encoding elastin binding protein) and bbp (encoding bone sialo-protein binding protein), was performed by PCR.
Results: The clfAB genes were detected among all the isolates. The prevalence of fnbA, fnbB, fib, eno, cna, ebps and bbp was 63%, 6%, 50%, 59%, 82%, 63%, 9% and 0%, respectively.
Conclusion: The high prevalence of these genes is important for future plans in vaccine designation. MRSA and MSSA isolates similarly can produce adhesive surface proteins for colonization.
Mohsen Mirzaee; Shahin Najar Peerayeh; Abdol-Majid Ghasemian
Volume 9, Issue 4 , October 2014, , Pages 257-262
Abstract
Background & Objectives: Methicillin resistance Staphylococcus aureus (MRSA) is one of the most important pathogens that causes several nosocomial and community infections. Adhesion to surfaces and biofilm formation is considered main step in staphylococcal infection. The aims of this study ...
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Background & Objectives: Methicillin resistance Staphylococcus aureus (MRSA) is one of the most important pathogens that causes several nosocomial and community infections. Adhesion to surfaces and biofilm formation is considered main step in staphylococcal infection. The aims of this study were to determine presence oficaABCD genes and relation to the biofilm formation in of MRSA isolates. Methods: Of the 63 MRSA clinical isolates collected from selected hospitals in Tehran, Iran,quantitative biofilm formation was determined by microtiter tissue culture plates (MtP). All MRSA isolates were examined for determination the icaABCD genes by using PCR method. Results: twenty nine (46%) of the isolates were strong produced biofilm on Mtp. All of the MRSA isolates carried icaD and icaC genes, whereas, the prevalence of icaA and icaB was 60.3% and 51% respectively. Conclusions: S. aureus clinical isolates have different capacity to production biofilm and adhesion. This may be caused by a different in the expression of biofilm genes and hetrogenicity in genetic origins.
Mohsen Mirzaee; Parviz Owlia; Mohammad Reza Mehrabi; Amir Gharib
Volume 4, Issue 4 , September 2009, , Pages 151-156
Abstract
Background and Objectives: The most common problems limiting the medical use of aminoglycosides have been the nephro- and oto-toxicities as well as the increasing bacterial resistance. Encapsulation of drugs into liposomes enhances their efficacy while reducing their toxicities. The aim of this ...
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Background and Objectives: The most common problems limiting the medical use of aminoglycosides have been the nephro- and oto-toxicities as well as the increasing bacterial resistance. Encapsulation of drugs into liposomes enhances their efficacy while reducing their toxicities. The aim of this study was to evaluate the antimicrobial activity of free and liposomal amikacin. Material and Methods: Encapsulated amikacin into liposome was prepared by sonication. The drug contained in the liposome was measured by HPLC after lysis of vesicles by 0.2% Triton X-100. The amikacin kinetic released from liposomes in the presence of normal human pooled plasma was also evaluated. The MICs of this drug for Pseudomonas. aeruginosa (ATCC 27853), Escherichia. coli (ATCC 25922), Streptococcus. faecalis (ATCC 29212) and Staphylococcus. aureuse (ATCC 29213) were determined and compared to those of the respective free drug using a broth dilution method. Results: In the presence of plasma, liposomal retention of amikacin was 80.25 ± 0.55% (P ≤ 0.05) after 1 h of incubation and then remained nearly constant over a 24 h period of the study. The encapsulation efficiency of liposomal preparation was 24.36% ± 0.14 (P ≤ 0.05) of the initial amount of the drug in solution. The MICs of liposomal amikacin against all bacterial strains tested were lower than MICs of free amikacin. Conclusion: The amikacin appears a promising approach in the management of bacterial infections and should be further evaluated in vivo experiments.