ABSTRACT
Matrix-assisted laser-desorption/ionization time-of-flight (MALDI-TOF) is positioned at the forefront of bacterial identification in the future. Its performance needed to be evaluated in a routine Bacteriology laboratory to determine its true benefits. A prospective study was carried out in the Bacteriology laboratory of the Pellegrin University Hospital in Bordeaux, France, from April to May 2009. Bacterial isolates from clinical samples were identified by conventional phenotypic bacteriological methods [Phoenix (Becton-Dickinson) or API strips (bioMérieux)] and in parallel with a mass spectrometer (Ultraflex III TOF/TOF and the biotyper database from Bruker Daltonics). In case of a discrepancy between these results at the genus level, a 16S rRNA and/or rpoB gene sequencing was performed. Of the 1013 bacteria tested, 837 (82.6%) were correctly identified at the species level by MALDI-TOF mass spectrometry (MS) without extraction and 189 after extraction, i.e. 986 (97.3%) were correctly identified at the species level by MALDI-TOF MS, vs. 945 (93.2%) by phenotypic methods. Indeed, the extraction step was necessary for only 15% of the isolates. These results were even better when considering the genus, reaching almost 99% with MALDI-TOF MS and 98% with phenotypic methods. The performance of MALDI-TOF MS is very attractive considering its efficiency and rapidity, and the technique constitutes a precious tool for bacteriological identification in a routine laboratory.
Subject(s)
Bacterial Infections/diagnosis , Bacteriological Techniques/methods , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , France , Hospitals, University , Humans , Prospective Studies , Sensitivity and SpecificityABSTRACT
Hepatitis B virus (HBV) ENI enhancer can activate the expression of HBV and non-HBV genes in a liver-specific manner. By performing the electrophoretic mobility-shift assays, we demonstrated that the three related, liver-enriched, transcription factors, HNF3 alpha, HNF3 beta, and HNF3 gamma could all bind to the 2c site of HBV ENI enhancer. Mutations introduced in the 2c site to abolish the binding by HNF3 reduced the enhancer activity approximately 15-fold. Moreover, expression of HNF3 antisense sequences to suppress the expression of HNF3 in Huh-7 hepatoma cells led to reduction of the ENI enhancer activity. These results indicate that HNF3 positively regulates the ENI enhancer activity and this regulation is most likely mediated through the 2c site. The requirement of HNF3 for the ENI enhancer activity could explain the liver specificity of this enhancer element.
Subject(s)
DNA-Binding Proteins/metabolism , Enhancer Elements, Genetic , Hepatitis B virus/genetics , Liver/metabolism , Nuclear Proteins/metabolism , Transcription Factors , Base Sequence , Genes, Viral , Hepatocyte Nuclear Factor 3-alpha , Hepatocyte Nuclear Factor 3-beta , Hepatocyte Nuclear Factor 3-gamma , Humans , Molecular Sequence Data , Oligodeoxyribonucleotides , Protein Binding , Tumor Cells, CulturedABSTRACT
Partial dentures with free end saddles, classified as K I and II present special design problems because of the different properties of tooth support and mucosa support. The main principle is that strait saddles are designed as tooth-born, however in curved saddles tooth and mucosa-born dentures are preferred. The article describes so called "altered cast" clinical and laboratory procedure which prevents rocking of the denture around the fulcrum line in patients with resilient alveolar ridge mucosa. Besides that some typical designs of partial dentures are presented.
