ABSTRACT
PURPOSE: Linezolid is an effective drug against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). We describe the emergence of linezolid resistance in MRSA and VRE from India. MATERIAL AND METHODS: One MRSA and two VRE strains were isolated from a patient on linezolid therapy of one week duration. All three isolates were resistant to linezolid with minimal inhibitory concentrations (MIC) ≥4 mg/L. The 746-bp region flanking the possible G2576U mutation on the corresponding DNA from the 23S rRNA was amplified by polymerase chain reaction (PCR) and amplicons were sequenced for all the three isolates. Conjugation experiments using the linezolid resistant MRSA (LRMRSA) and linezolid resistant VRE (LRVRE) isolates as donors and wild strains of corresponding genera as recipients were performed. RESULTS: The MRSA isolate had the classical G2576U mutation. High quality value scores in the sequencing software validated the mutation. Conjugation studies did not indicate presence of transferable resistance for linezolid. Sequencing did not indicate presence of any mutation in the two LRVRE isolates. CONCLUSIONS: This is the first report from India citing resistance in Staphylococcus and Enterococcus against Linezolid.
Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Bacterial , Enterococcus faecium/drug effects , Linezolid/pharmacology , Point Mutation , Staphylococcus aureus/drug effects , Aged, 80 and over , Anti-Bacterial Agents/therapeutic use , Conjugation, Genetic , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Enterococcus faecium/genetics , Enterococcus faecium/isolation & purification , Gram-Positive Bacterial Infections/drug therapy , Gram-Positive Bacterial Infections/microbiology , Humans , India , Linezolid/therapeutic use , Male , Microbial Sensitivity Tests , Polymerase Chain Reaction , RNA, Ribosomal, 23S/genetics , Sequence Analysis, DNA , Staphylococcus aureus/genetics , Staphylococcus aureus/isolation & purificationABSTRACT
A novel series of benzoyl urea derivatives was prepared and identified as NR2B selective NMDA receptor antagonists. The influence of the substitution of the piperidine ring on the biological activity of the compounds was studied. Compound 9 was active in the formalin test in mice.
Subject(s)
Benzoates/chemical synthesis , Benzoates/pharmacology , Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors , Urea/analogs & derivatives , Urea/chemical synthesis , Urea/pharmacology , Chromatography, High Pressure Liquid , Fluorometry , Formaldehyde , Indicators and Reagents , Magnetic Resonance Spectroscopy , Mass Spectrometry , Pain Measurement/drug effects , Spectrophotometry, InfraredABSTRACT
High-performance liquid chromatography combined with a UV absorbance detector and electrospray ionization mass spectrometer is used for the simultaneous analysis of moexipril and moexiprilat in biological samples. Moexipril and moexiprilat are determined in samples metabolized by rat and human liver microsomal preparations, and also in rat urine. The calibration curve is linear in the ng/mL and microg/mL concentration range of the injected moexipril.
