Emergence of vancomycin-intermediate Staphylococcus aureus (VISA) and vancomycin-resistant S. aureus (VRSA) strains has led to global concerns about treatments for staphylococcal infections. These strains are currently rare even though there is an upward trend in their reported incidence. Therefore, appropriate screening and epidemiological evaluation of VRSA strains can affect future global health care policies. Isolates of Staphylococcus aureus were obtained from various clinical samples and were then evaluated with agar screening, disk diffusion, and MIC methods to determine resistance to vancomycin and methicillin. After confirmation of the isolated VRSA strain, genetic analysis was performed by evaluating mecA and vanA gene presence, SCCmec, agr, and spa types, and toxin profiles. Multilocus sequence typing (MLST) and plasmid analysis were also performed. The VRSA strain was resistant to oxacillin (MIC of 128 g/ml) and vancomycin (MIC of 512 g/ml). Disk diffusion antimicrobial susceptibility tests showed resistance to oxacillin, vancomycin, levofloxacin, ciprofloxacin, trimethoprim-sulfamethoxazole, clindamycin, rifampin, and tetracycline. The isolate was susceptible to minocycline and gentamicin. PCRs were positive for the mecA and vanA genes. Other genetic characteristics include SCCmec type III, agr I, spa type t037, and sequence type (ST) 1283. The plasmid profile shows five plasmids with a size of ϳ1.7 kb to >10 kb. The isolated VRSA strain was obtained from a critically ill hospitalized patient. Genetic analysis of this strain suggested that the strain was a methicillin-resistant S. aureus (MRSA) clone endemic in Asia that underwent some genetic changes, such as mutation in the gmk gene and acquisition of the vanA gene.

Chronic infection with Pseudomonas aeruginosa is the main proven perpetrator of lung function decline and ultimate mortality in cystic fibrosis (CF) patients. Mucoid strains of this bacterium elaborate mucoid exopolysaccharide, also referred to as alginate. Alginate-based immunization of naïve animals elicits opsonic antibodies and leads to clearance of mucoid P. aeruginosa from the lungs. Alginate was isolated from mucoid P. aeruginosa strain 8821M by repeated ethanol precipitation, dialysis, proteinase and nuclease digestion, and chromatography. To improve immunogenicity, the purified antigen was coupled to tetanus toxoid (TT) with adipic acid dihydrazide (ADH) as a spacer and 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDAC) as a linker. The reaction mixture was passed through a Sepharose CL-4B column. The resulting conjugate was composed of TT and large-size alginate polymer at a ratio of about 3 : 1; it was non-toxic and non-pyrogenic, and elicited high titres of alginate-specific IgG. Antisera raised against the conjugate had high opsonic activity against the vaccine strain. The alginate conjugate was also able to protect mice against a lethal dose of mucoid P. aeruginosa. These data indicate that an alginate-based vaccine has significant potential to protect against chronic infection with mucoid P. aeruginosa in the CF host.

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Our results showed a correlation between presence of virulence gene and antibiotic resistance in K. pneumoniae.

Ureaplasma urealyticum is a causative agent of non-gonococcal urethritis and is implicated in the pathogenesis of prostatitis, epididymitis and infertility. The organism is more common in partners of infertile than fertile marriages. U. urealyticum infections not only jeopardize fertility but also pose a risk for infertility treatment and resulting pregnancies. The aim of this study was to determine the prevalence of U. urealyticum and Ureaplasma parvum in semen of infertile and healthy men by polymerase chain reaction (PCR). Semen samples were obtained from infertile patients and healthy controls and were subjected to the routine andrological analysis and PCR. DNA was extracted by the Cadieux method, and analysed by PCR protocol with specific primers for urease and multiple-banded antigen genes. Ureaplasmas were detected significantly by PCR in 12 of 100 (12%) semen specimens from infertile patients and in three of 100 (3%) healthy men. The volume of semen fluid, concentration of sperm cells, and sperm cell with normal morphology were significantly decreased in infertile men. In the group of infertile patients with PCR positive for Ureaplasmas, the volume, count and morphology of semen samples were lower than in the infertile patients with PCR-negative results. U. urealyticum species in semen of infertile men was found to be high (9%) than in healthy controls (1%). Detection rate for U. parvum was 3% in the infertile group and 2% in healthy men. The results indicate that U. urealyticum species is more common in specimens of infertile men. The percentage of normal sperm cells, the volume of semen and the percentage of sperm cells with motility in the PCR positive for U. urealyticum species group were lower than in the PCR positive for U. parvum group.

Background: Multiple drug-resistant strains of Acinetobacter have become common in hospitals worldwide. The problem becomes more acute with increasing resistance to carbapenems, the last resort in the treatment of hospital acquired Acinetobacter baumannii infections. Objectives: The current study was conducted to determine the antimicrobial susceptibility patterns and prevalence of OXA-type carbapenemases, among clinical isolates of A. baumannii, in Tehran hospitals, Iran. Materials and Methods: Isolates were identified as A. baumannii by PCR with specific primers for bla OXA-51-like gene. Their susceptibilities to different antibiotics were determined using disk diffusion method. Isolates were then subjected to multiplex-PCR targeting bla oxa-51, bla oxa-24, blaoxa-23 and bla oxa-58 genes. Results: Results showed that 123 of 131 (93.89%) Acinetobacter species, possessed bla oxa-51-like gene and were identified as A.baumannii. 54.47% of isolates were resistant to amikacin, 67.47% resistant to imipenem and 84.55% resistant to meropenem.All isolates were susceptible to colistin and polymixin B. 43 of 123 A. baumannii isolates(34.95%)were MDR. These isolates were resistant to amikacin, ciprofloxacin, imipenem, cefrazidim. Among 123 isolates, 100 (81.3 %) had an acquired oxa-23like carbapenemase 10 (8.1%) possessed oxa-24-like, and 1 (0.81%) possessed oxa-58-like carbapenemase. Conclusions: The present study showed that bla OXA-23-like was the most frequent carbapenemase identified among carbapenemresistant A. baumannii isolated in Tehran hospitals. Evaluation of antibiotic resistance genes in A. baumannii, is necessary to control further dissemination of these antibiotic resistant genes.

This genotyping panel can be a useful tool for detection of virulent H. pylori isolates and can provide valuable guidance for prediction of the clinical outcomes.

ScienceKlebsiella pneumoniae (K. pneumoniae) is one of the most common causes of nosocomial and opportunistic infections. This microorganism is involved in pneumonia, bacteremia, septicemia, diarrhea, wound infections, and infections of the urinary tract, bones, joints, and central nervous system. 1 The spread of extended-spectrum β-lactamase (ESBL) producing K. pneumoniae infections is an increasing public health problem internationally. ESBLcarrying microorganisms are resistant to third-generation cephalosporin antibiotics and have cross-resistance to aminoglycosides and quinolones. [2][3][4] CTX-M β-lactamases are the most prevalent types of ESBL worldwide. Phylogenetically, these enzymes have been classified into 5 major groups based on their amino acid sequence similarities: the CTX-M-1 cluster (CTX-M-1, -3, -10, -11, -12, -15, and -28, as well as FEC-1), the CTX-M-2 cluster (CTX-M-2, -4, -5, -6, -7, and -20, as well as TOHO-1), the CTX-M-8 cluster (CTX-M-8), the CTX-M-25 cluster , and the CTX-M-9 cluster (and -27, as well as TOHO-2). 5-7 The primary mechanism of resistance to aminoglycosides is the expression of aminoglycoside-modifying enzymes. ABSTRACTObjective: To determine the prevalence of extended-spectrum beta lactamases (ESBLs), the bla CTX-M genes, and aminoglycoside modifying enzymes genes in clinical isolates of Klebsiella pneumoniae (K. pneumoniae).Methods: We collected 200 nonduplicate clinical isolates of K. pneumoniae in hospitals in Tehran, Iran. We determined antibacterial susceptibility and confirmed ESBL production via the disk diffusion and minimum inhibitory concentration (MIC) methods. We identified bla CTX-M and aminoglycoside modifying enzymes genes via polymerase chain reaction (PCR). Results:We detected 72 (36.0%) ESBL-positive K. pneumoniae, in which the bla CTX-M-15 was dominant (62.5%). A total of 54.0% of isolates were resistant to at least 1 tested aminoglycoside; also, we detected aac(6')-Ib in 42.5% of isolates and aac(3)-IIa in 35.1% of them. We observed a high rate of aminoglycoside-resistant genes (71.0%) among bla CTX-M-15 -carrying isolates. Conclusion:We report that CTX-M-15 is the dominant type of CTX-M, which associates with entities that have high aminoglycoside resistance. Continuous surveillance and monitoring of this entity are needed because the codissemination of multiple drug-resistant genes with K. pneumoniae may become a serious therapeutic problem.