Trade-off between pulse rate and radiation dose during modified barium swallow examination: what is the reality?

AIM: To evaluate the effect of modification of dose mode and frame rate on patient radiation dose during modified barium swallow (MBS) examinations. MATERIALS AND METHODS: A retrospective review was undertaken of consecutive MBS examinations performed over 6 months in the inpatient setting. Patients were divided into two cohorts: pre-implementation of the MBS Impairment Profile (MBSImP; low rate, normal dose) and post-implementation (high rate, low dose). Prior to implementation, pulse rate and dose testing were performed on multiple phantoms. RESULTS: Four hundred and forty-nine patients were included in the pre-implementation cohort and 378 in the post-implementation cohort. Phantom dose testing demonstrated no significant difference in dose on either phantom between low rate/normal dose and high rate/low dose modes. Prior to MBS standardisation, the mean radiation dose was 5.86 (±4.35) mGy. Following standardisation, the mean radiation dose was 4.72 (±3.77) mGy (p<0.0001). The mean fluoroscopy time for MBS prior to standardisation was 83.8 (±44.4) seconds and the mean fluoroscopy time for MBS after standardisation was 82.3 (±39.8) seconds (p=0.62). The dose rate for MBS prior to standardisation was 4.35 (±2.42) and the dose rate for MBS after standardisation was 3.55 (±2.41) mGy/s (p<0.0001). CONCLUSION: Adjustments made to lower the dose mode and the increase in fluoroscopy frame rate decreased the patient radiation dose and did not increase fluoroscopy time.

In vitro effect of clarithromycin and alginate lyase against helicobacter pylori biofilm.

It is now established that the gastric pathogen Helicobacter pylori has the ability to form biofilms in vitro as well as on the human gastric mucosa. The aim of this study is to evaluate the antimicrobial effects of Clarithromycin on H. pylori biofilm and to enhance the effects of this antibiotic by combining it with Alginate Lyase, an enzyme degrading the polysaccharides present in the extracellular polymeric matrix forming the biofilm. We evaluated the Clarithromycin minimum inhibition concentration (MIC) on in vitro preformed biofilm of a H. pylori. Then the synergic effect of Clarithromycin and Alginate Lyase treatment has been quantified by using the Fractional Inhibitory Concentration index, measured by checkerboard microdilution assay. To clarify the mechanisms behind the effectiveness of this antibiofilm therapeutic combination, we used Atomic Force Microscopy to analyze modifications of bacterial morphology, percentage of bacillary or coccoid shaped bacteria cells and to quantify biofilm properties. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1584-1591, 2016.

Immunofluorescence on pronase-digested paraffin sections: a valuable salvage technique for renal biopsies.

Direct immunofluorescence (IF) on frozen tissue is the method of choice for the study of medical renal diseases. When no glomeruli are available, IF can be performed on the formalin-fixed paraffin-embedded tissue allocated for light microscopy after antigen retrieval with proteases. In this study, the results of IF on frozen tissue (IF-F) and on deparaffinized, pronase-treated tissue (IF-P) were compared in 71 renal biopsies representing 12 major renal diseases. Using IF-P, diagnostic findings were obtained in 100% of cases of lupus nephritis, acute post-infectious glomerulonephritis, cryoglobulinemic glomerulonephritis, fibrillary glomerulonephritis, primary amyloidosis, myeloma cast nephropathy, and light-chain Fanconi syndrome (LCFS), 88% of cases of immunoglobulin (Ig)A nephropathy, 80% of cases of light-chain deposition disease, 60% of cases of membranoproliferative glomerulonephritis type 1, 50% of cases of idiopathic membranous glomerulopathy (MGN) and 20% of cases of anti-glomerular basement membrane (GBM) disease. IF-P was less sensitive than IF-F for the detection of C3 in all disease categories and for the detection of IgG in cases of MGN and anti-GBM disease. The diagnostic kappa light-chain staining was demonstrated in 100% of cases of LCFS by IF-P versus 40% by IF-F. We conclude that IF-P is a valuable salvage immunohistochemical technique for renal biopsies lacking adequate cortical sampling for IF-F, and is superior to IF-F for the diagnosis of LCFS.