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Classical (CKp) and hypervirulent (hvKp) Klebsiella pneumoniae are two different circulating pathotypes. The aim of this study was to assess the prevalence, epidemiology and molecular relatedness of hvKps using a systemic review and meta-analysis. The data extracted from Medline, Embase, and Web of Science and finally 14 studies met the eligible criteria. To combine prevalence proportions of all studies, we performed the metaprop command embedded in the Meta package software. Totally, of 1814 K. pneumoniae isolates, 21.7% (394/1814) were hvKp. The molecular typing showed that all hvKp isolates were grouped into 50 different sequence types (STs) of them ST23, ST11, ST65 and ST86 were common. K1, K2 and K64 were dominant capsule serotypes that strongly related to ST23, ST65 and ST11, respectively. It seems that clonal group 23 (CG23) is associated with liver abscess and CG11 related to various clinical sources.

Background: Silver nanoparticles (AgNPs) were phyto-synthesized using Typha azerbaijanensis aerial part and root extracts, and their biological activities were investigated. Methods: This study was conducted in the Science and Research Branch, Islamic Azad University, Tehran, Iran in 2019. In this experimental study, silver nanoparticles (AgNPs) were phyto-synthesized and the physicochemical properties of AgNPs were determined using UV-Vis (UV-Vis) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy. Antibacterial and anticancer activity of synthesized AgNPs was determined using microdilution assay, and MTT 3- (4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) methods, respectively. The apoptotic effects of AgNPs were investigated using Real-Time PCR and flow cytometry techniques. Results: Morphological analysis of the synthesized AgNPs confirmed the spherical shape of AgNPs with an average size of 10.67 to 16.69 nm. The FTIR spectrum confirmed the presence of phytochemicals from T. azerbayenensis extract at the AgNP surface. Antibacterial experiments showed that phyto-fabricated AgNPs had significant antibacterial activity against Gram-negative bacteria. The AgNPs were significantly cytotoxic against breast cancer cell line (MCF-7) through induction of apoptosis. Conclusion: The phyto-synthesized AgNPs had biological activities could be useful in pharmaceutical applications.

Background and Objectives: Bordetella holmesii is associated with a pertussis-like respiratory syndrome in healthy individuals and also a rare cause of septicaemia, endocarditis, pneumonia, and septic arthritis, mostly in immunocompromised patients. Culture technique and real-time PCR are 2 methods used to detect Bordetella spp. Materials and Methods: In this study, 435 nasopharyngeal specimens of patients with suspected whooping cough were checked for the presence of B. holmesii using 2 methods of culture technique and real-time PCR. Results: In this study, we detected hIS1001 and IS481 of B. holmesii in 2 infants suspected of having pertussis-like syndrome. Conclusion: Our observations demonstrate that accurate diagnosis is needed to discriminate between B. holmesii and B. pertussis infections among pertussis cases; otherwise, it could lead to misestimating pertussis rate and vaccine efficacy.

Background and objectives: Klebsiella species are of the most common bacteria involved in nosocomial and urinary tract infections. Genetic elements such as class 1 integrons have an important role in the resistance development. In this study, the share of class 1 integrons, the genetic characterization of the integron cassettes and PFGE profiles of the clinical Klebsiella isolates are evaluated in Besat University hospital of Sanandaj, Iran. Methods: Isolates from 17890 clinical specimens were identified by API20E. Antibiotic susceptibility testing and MIC were done for MDR isolates. For investigating class 1 integrons and gene cassettes, PCR by intI1 integrase and 5΄-CS/3΄-CS were performed. Integrated gene cassettes were analyzed by PCR-RFLP and sequencing. Pulsed-Field Gel Electrophoresis was carried out for studying of clonality outbreak of isolates. Results: Thirty five Klebsiella spp. were isolated and included 29 K. pneumoniae and six K. oxytoca. All the isolates were susceptible to carbapenems while other antibiotics showed high resistant profile. In all Klebsiella spp. PCR for intI1 integrase and 5΄-CS/3΄-CS were positive (100%). Sequencing for prevalent bands of internal variable regions between 5΄-CS/3΄-CS showed arr-5, orfD-aacA4 and aad5- dfrA17. PFGE Analysis showed 18 clusters in K. pneumoniae with clonality relatedness in some cases but no relatedness among K. oxytoca isolates. Conclusion: High prevalence of class 1 integron carrying gene cassettes confirms that integron-mediated antimicrobial gene cassettes are important in Klebsiella spp. resistance profile. Clone diffusions of MDR Klebsiella spp. which harbor class 1 integrons have threaten the potential in the resistance development in our clinical settings.