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Objectives Carbapenem-resistant Klebsiella pneumoniae infections are associated with increased rates of treatment failure and death. Several studies have reported isolates with a combined hypervirulent and antimicrobial-resistant phenotype. Methods In this study, the molecular characteristics of hypervirulent K. pneumoniae (hvKP) isolated from mechanically-ventilated patients admitted to a toxicological intensive care unit (ICU) in Tehran, Iran, were examined. String test, antimicrobial susceptibility testing, virulence factors analysis and plasmid replicon typing were performed. The clonal relatedness of the isolates was analysed by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Results hvKP accounted for 9.4% (5/53) of K. pneumoniae isolated from ventilator-associated pneumonia among patients admitted to the ICU with acute drug poisoning. The mortality rate was 7.5% (4/53) among K. pneumoniae-infected patients. All fatal K. pneumoniae were hvKP isolates, were resistant to imipenem and harboured an aacA7, blaVIM-2 and dhfrI cassette arrangement in a class 1 integron. The isolates were shown to be ST23 (Pasteur scheme) and exhibited similar PFGE patterns. Plasmid analysis revealed a class 1 integron harbouring blaVIM-2 located on an ca. 45-kb IncN plasmid. Conclusion Here we describe the emergence of VIM-2-producing hvKP serotype K1/ST23 in an outbreak with high mortality in a hospital toxicological ICU. It appears that we must alert and prepare the hospital’s surveillance system for the appearance, expansion and clinical importance of new K. pneumoniae clones associated with high antimicrobial resistance and robust virulence capabilities.

BACKGROUND Resistant Helicobacter pylori to commonly used antimicrobial agents are associated with severe upper gastrointestinal disorders. To provide an epidemiological picture of H pylori and characterize the resistance pattern and genetic variation of clinical isolates, stomach biopsies from patients with functional dyspepsia were evaluated in northeast of Iran. MATERIALS AND METHODS In this study, 80 patients were recruited. Finally, fifty H pylori strains were isolated from antrum and corpus biopsies by culturing on Columbia agar. All strains were identified by standard laboratory procedures. Susceptibility testing of antibiotics was performed using minimum inhibitory concentration test. Allele-specific primer (ASP)-PCR of 23S rRNA which associated with clarithromycin resistance was done among resistant strains. Moreover, cagA gene and polymorphism in vacA were detected. Random amplified polymorphic DNA polymerase chain reaction (RAPD-PCR) was applied to investigate the genetic variations among all strains. RESULTS Antibiotic resistance pattern of H pylori strains was as follows: 68% (34/50) to metronidazole, 50% (25/50) to rifampicin, 30% (15/50) to amoxicillin, 28% (14/50) to levofloxacin, 22% (11/50) to clarithromycin, and 16% (8/50) to tetracycline. Multidrug-resistant strains were observed in 19 strains (38%). ASP-PCR of 23S rRNA showed four strains had A2143G mutation, six strains had A2142G mutation, and one strain had a Wt+A2143G mutation. Amplification of virulence-associated genes revealed that cagA was present in 27 isolates (54%) and vacA in 36 isolates (72%). The most common genotype of H pylori was vacA s1am2 (40%) followed by vacA s2m2 (14%), vacA s1am1 (12%), vacA s1bm1 (4%), and vacA s1bm2 (2%). DNA fingerprinting pattern indicated a high heterogeneity among isolated strains. CONCLUSION An alarming level of resistance to metronidazole and rifampicin and high heterogeneity among H pylori isolates highlighted the importance of continued monitoring of antimicrobial susceptibility and epidemiological surveillance of this pathogen.

In the current study, we synthesized new vanadyl complexes of the N,N′-dipyridoxyl(1,2-propanediamine) Schiff bases and characterized them by experimental and theoretical methods. Also, the antibacterial (against strains of S. aureus, P.aeruginosa and E. coli) and cytotoxicity activities of three V(IV) complexes including VO-EN, VO-13 and VO-12 of the pyridoxal SBs were evaluated against human prostate tumor cells (PC3 cell line), where the VO-EN, VO-13 and VO-12 species are V(IV) complexes of the N,N′-dipyridoxyl(ethylenediamine), N,N′-dipyridoxyl(1,3-propanediamine) and N,N′-dipyridoxyl(1,2-propanediamine) Schiff bases, respectively. Deprotonated form of the N,N′-dipyridoxyl(1,2-propanediamine) Schiff base acts as a tetradentate N2O2 ligand, which coordinates to the V(IV) via two phenolate oxygens and two azomethine nitrogens. In the square-pyramidal geometry of the synthesized complex (VO-12), an oxo ligand occupies the apical position. The analyzed results for the VO-12 complex were in agreement with the experimental tests, confirming the suitability of its optimized geometry. The synthesized VO-12 complex displays significant and reusable catalytic activities in synthesis of the tetrahydrobenzo[b]pyrans, where the V4+ central ion is the active site of the catalyst. All investigated SB complexes were active against P.aeruginosa, while VO-13, VO-12 and VO-EN complexes revealed no activity against E. coli and S. aureus, respectively. All complexes showed considerable cytotoxic against PC3 cells. Our results suggested that these complexes decreased the cell viability after 48 h and the VO-12 complex showed the highest cytotoxicity. These observations suggested that the VO-EN, VO-13 and VO-12 species can be cytotoxic materials for pharmaceutical applications. In addition, in a dose-dependent manner, these compounds can be consider as potent antimicrobial agents.

Carbapenem-resistant Klebsiella pneumoniae infections are associated with increased rates of treatment failure and death. Several studies have reported isolates with a combined hypervirulent and antimicrobial-resistant phenotype.In this study, the molecular characteristics of hypervirulent K. pneumoniae (hvKP) isolated from mechanically-ventilated patients admitted to a toxicological intensive care unit (ICU) in Tehran, Iran, were examined. String test, antimicrobial susceptibility testing, virulence factors analysis and plasmid replicon typing were performed. The clonal relatedness of the isolates was analysed by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST).hvKP accounted for 9.4% (5/53) of K. pneumoniae isolated from ventilator-associated pneumonia among patients admitted to the ICU with acute drug poisoning. The mortality rate was 7.5% (4/53) among K. pneumoniae-infected patients. All fatal K. pneumoniae were hvKP isolates, were resistant to imipenem and harboured an aacA7, blaHere we describe the emergence of VIM-2-producing hvKP serotype K1/ST23 in an outbreak with high mortality in a hospital toxicological ICU. It appears that we must alert and prepare the hospital's surveillance system for the appearance, expansion and clinical importance of new K. pneumoniae clones associated with high antimicrobial resistance and robust virulence capabilities.

Crimean-Congo hemorrhagic fever (CCHF) is a disease prevalent among humans and animals and is endemic in Iran. Although CCHF has been reported in all of its neighboring provinces, in Mazandaran in northern Iran there have been no reports of any cases of human infection. This research has been carried out to clarify the epidemiological aspects of CCHF infection among sheep in various geographical regions of Mazandaran province. In this survey, 270 blood samples were collected from sheep in eastern, central, and western Mazandaran between 2010 and 2011, and the specific ELISA test for CCHF virus was carried out on the blood samples in the National Reference Laboratory in the Pasteur Institute, Tehran, Iran. The CCHF infection rate according to this study was 3.7%. A weak statistical relationship (p=0.063) was seen between the different geographical regions, with a gradual decrease in the infection rate noted, stretching from the eastern to the western portions of the province (eastern 6.8%, central 2.8%, and western 0%). Older sheep were 2.7 times more likely to be infected with the virus (OR 2.70; 95% CI 1.50,4.87; p