Genotyping of Francisella tularensis strains by pulsed-field gel electrophoresis,amplified fragment length polymorphism fingerprinting,and 16S rRNA gene sequencing

We evaluated three molecular methods for identification of Francisella strains: pulsed-field gel electrophoresis (PFGE), amplified fragment length polymorphism (AFLP) analysis, and 16S rRNA gene sequencing. The analysis was performed with 54 Francisella tularensis subsp. holarctica, 5 F. tularensis subsp. tularensis, 2 F. tularensis subsp. novicida, and 1 F. philomiragia strains. On the basis of the combination of results obtained by PFGE with the restriction enzymes XhoI and BamHI, PFGE revealed seven pulsotypes, which allowed us to discriminate the strains to the subspecies level and which even allowed us to discriminate among some isolates of F. tularensis subsp. holarctica. The AFLP analysis technique produced some degree of discrimination among F. tularensis subsp. holarctica strains (one primary cluster with three major subclusters and minor variations within subclusters) when EcoRI-C and MseI-A, EcoRI-T and MseI-T, EcoRI-A and MseI-C, and EcoRI-0 and MseI-CA were used as primers. The degree of similarity among the strains was about 94%. The percent similarities of the AFLP profiles of this subspecies compared to those of F. tularensis subsp. tularensis, F. tularensis subsp. novicida, and F. philomiragia were less than 90%, about 72%, and less than 24%, respectively, thus permitting easy differentiation of this subspecies. 16S rRNA gene sequencing revealed 100% similarity for all F. tularensis subsp. holarctica isolates compared in this study. These results suggest that although limited genetic heterogeneity among F. tularensis subsp. holarctica isolates was observed, PFGE and AFLP analysis appear to be promising tools for the diagnosis of infections caused by different subspecies of F. tularensis and suitable techniques for the differentiation of individual strains.     

Spectral discrimination of Cerenkov radiation in scintillating dosimeters

Radiation therapy accelerators require highly accurate dose deposition and the output must be monitored frequently and regularly. Ionization chambers are the primary tool for this control, but their size, their high voltage needed, and the correction needed for electrons make them unsuitable for use during patient treatment. We have developed a small (1-mm-diam and 1-mm-long active part), flexible, and water-equivalent dosimeter. It is suitable for photon and electron beams without corrections, and performs on line dose measurements. This detector is based on only one scintillating fiber and a CCD camera. A new signal processing is used to remove the effect of Cerenkov radiation background, which only requires a preliminary calibration. Central-axis depth-dose distribution comparisons have been achieved with standard ionization chambers, over a range from 8 to 25 MV photons and from 6 to 21 MeV electrons in order to validate this calibration. Results show a very good agreement, with less than 1% difference between the two detectors.     

Fractionation and biological characterization of Olea europea pollen extract

Preliminary fractionation of Olea european pollen extract has been performed. At least 10 antigenic fractions have been found by crossed electrophoresis. After Sephadex gel filtration, two fractions with a molecular weight of 160,000 and 65,000 have been obtained. The fractions were evaluated for allergenic activity by two in vitro techniques: polystyrene tube radioimmunoassay (PTRIA) and basophil degranulation test (BDT), and by skin tests. All tests indicated that the most reactive fractions were those in the 65,000 molecular weight peak. BDT has been shown to be a very reliable method as compared with histamine release and other parameters. Although common antigenic fractions have been found for Lollium perenne and O. europea, no cross-allergenicity has been shown by PTRIA inhibition.     

A comparative study of the treatment of vesicoureteral reflux in childhood: a review of a series of 636 refluxing units

A number of 411 pediatric patients (636 refluxing renal units) diagnosed as having vesicoureteral reflux (VUR) were evaluated in our Hospital between 1985 and 1997. All the patients were divided in two historic groups based on the therapeutical modalities employed. The children included in group A (between 1985 and 1995) were medically or surgically treated according to the grade of reflux. In the group B (between 1995 and 1997), the endoscopic treatment was added to previous. All cases underwent urine cultures, renal ultrasonography, voiding cystourethrography and isotopic gammagraphy with DMSA scan. In some patients were performed radionuclide renography with DTPA or MAG-3 to assess renal function. We consider that medical management is required in low grade reflux (I and II) but patients with high grade reflux (IV and V) clearly benefit from early ureteral surgical reimplantation (Cohen technique). In our series, patients with reflux grade III are treated endoscopically with Teflon or PDMS (polydimethylsiloxane) with resolution of reflux in 82-92% after first injection.     

Bladder hyporeflexia caused by vinca alkaloids

Presentation of one case of hyporreflexic bladder like a first step of neurotoxicity due to Vinca alkaloids. These drugs produces peripheral neuropathies as usual, but in some rare occasions they may affect to the autonomic nervous system with its effects in the bladder producing hyporreflexic. This disease reverts spontaneously after suppressing drugs.