Production of 16S rRNA methylase has recently drawn attention as a novel aminoglycoside resistance mechanism in pathogenic gram-negative bacteria (1). It confers very-highlevel resistance to all aminoglycosides that are currently available for parenteral formulation. Six distinct genes, rmtA, rmtB, rmtC, rmtD, armA, and npmA, encoding their respective enzymes have been identified in clinical an...

2014 Using our ab initio band structure results, we calculate the transition temperature of Pb according to the Gaspari-Gyorffy theory. The calculated value is half the experimental one. The discrepancy is attributed to the rigid muffin tin approximation. A simple method with no adjustable parameters is developed to account for this approximation. The new transition temperature is in excellent ...

The present study aimed to develop a rational therapy based on the genetic epidemiology, molecular mechanism evaluation and in vitro antibiotic combinations activity in multidrug-resistant Acinetobacter baumannii (MDRAB). MDRAB was screened by the Kirby-Bauer method. The random amplified polymorphic DNA technique was used to establish genetic fingerprinting, and a series of resistance genes wer...

In this study, we report the insertion sequence ISPpu21 in the oprD porin gene of carbapenem-resistant Pseudomonas aeruginosa isolates from burn patients in Tehran, Iran. Antibiotic susceptibility tests for P. aeruginosa isolates were determined. Production of metallo-β-lactamases (MBLs) and carbapenemase was evaluated and the β-lactamase-encoding and aminoglycoside-modifying enzyme genes were ...

Sir, Methylation of 16S ribosomal RNA (rRNA) mediated by 16S rRNA methylase, which confers high-level aminoglycoside resistance (MICs .1024 mg/L) in Enterobacteriaceae, has recently emerged as a major medical problem worldwide. Until now, seven plasmid-encoded 16S rRNA methylases, ArmA, RmtA, RmtB, RmtC, RmtD, RmtE and NpmA, have been reported in various clinical Gram-negative isolates in multi...

OBJECTIVES 16S rRNA methyltransferases are an emerging mechanism conferring high-level resistance to clinically relevant aminoglycosides and have been associated with important mechanisms such as NDM-1. We sought genes encoding these enzymes in isolates highly resistant (MIC >200 mg/L) to gentamicin and amikacin from an Indian hospital and we additionally screened for the novel RmtF enzyme in 1...

Background & objective Multidrug-resistant Acinetobacter baumannii (MDR-AB) is an important nosocomial pathogen which is associated with significant morbidity and mortality, particularly in high-risk populations. Aminoglycoside-modifying enzymes (AMEs) and 16S ribosomal RNA (16S rRNA) methylation are two important mechanisms of resistance to aminoglycosides. The aim of this study was to determi...

INTRODUCTION This in vitro study compared the cytotoxic effects of three commercially available MTA formulations naming ProRoot MTA (PMTA), Angelus MTA (AMTA), and Root MTA (RMTA), with calcium-enriched mixture (CEM) cement and a new nanohybrid MTA (NMTA) on human dental pulp stem cells (DPSC). METHODS AND MATERIALS Four disc-shaped specimens of each material were prepared. After completion o...

Dormanit seeds of Hazel (Cworylus avellatta L.) re(luire a period of after-ripeniing at low temliperlat'ire before they beconme capable of subsequent germiination. (Gibberellic acid (GA;) c-n fully replace this requirement (2, 6). The identification of gibberellin-likz substar.s in extracts of chilled ( noni-dormant) seeds led Frankland and Wareiing (7) to suggest that gibberellin synthesis nma...

BACKGROUND Aminoglycosides are a group of antimicrobial agents still the most commonly used in the treatment of life-threatening bacterial infections in human and animals. The emergence and spread of 16S rRNA methylases, which confer high-level resistance to the majority of clinically relevant aminoglycosides, constitute a major public health concern. OBJECTIVES Our goal was to evaluate the d...