Molecular forensics in the precious Mediterranean red coral, Corallium rubrum: testing DNA extraction and microsatellite genotyping using dried colonies

Corallium rubrum is an overharvested precious coral submitted to strong environmental pressures. The development of new management tools such as assignment tests is crucial to assess the origin of traded colonies and to reinforce existing regulations in order to ultimately reduce poaching. As a starting point, we test the feasibility of DNA extractions and PCR amplifications of ten microsatellites using dried tissues such as those that can be obtained from traded or seized colonies. We genotype the same ten colonies conserved in alcohol and after five drying periods (from 7 days to 8 months) as well as ten dried colonies coming from a seizure conducted in 2009. Estimating the rate of negative PCRs through time, PCR repeatability and frequencies of null alleles, we demonstrate that dried colonies can be successfully genotyped. This study opens new avenues for the conservation of C. rubrum and other precious corals.     

Total joint replacement and blood loss: what is the best equation?

With the population aging, total joint replacements which are an effective method to restore patient’s mobility are an increasing necessity. However, such operations are known to entail serious blood loss, which may have dramatic consequences in patients with chronic diseases or when the prosthesis is revised, a situation where the blood loss is even higher. Therefore, formulas to better estimate the blood loss are available. These formulas may also be used for clinical studies to compare blood loss between different joint replacement techniques. The aim of this review is to provide a clear understanding of the formulas and to help physicians to further improve their blood loss estimation. Moreover, surgeons will then be able to choose the most accurate and user-friendly formula for more comparable data between clinical studies.     

How does susceptibility prevalence impact on the performance of disk diffusion susceptibility testing?

Antimicrobial disk diffusion susceptibility testing, devoted in a clinical context to predicting whether an antibiotic regimen will be effective, should be evaluated through predictive values. This approach implies that the susceptibility prevalence (frequency of susceptible, intermediate, and resistant isolates) affects the predictive value of a result. We quantified the influence of the susceptibility prevalence variation on the disk diffusion method performance through a modeling approach. Simulations based on a resampling procedure from two distinct minimum inhibitory concentration/diameter data sets were performed. Experimental variability on minimum inhibitory concentration and diameters was taken into account in the simulations. Results show that the susceptibility prevalence impact depends on the antibiotic and may be significant when prevalence variation is high enough. Consequences of these results on zone diameter breakpoint determination policy are discussed. This implies that the following should be done: (i) consider more rigorously the susceptibility prevalence in studies dealing with zone diameter breakpoint determination and performance evaluation, (ii) re-evaluate disk diffusion breakpoint consistency when the weight of prevalence variation is noteworthy, (iii) estimate consequences of a breakpoint international consensus on prediction quality and appropriate patient management.     

The Voice Track multiband single-channel modified Wiener-filter noise reduction system for cochlear implants: patients' outcomes and subjective appraisal

Objective: The aim of this study was to evaluate the potential improvements of speech perception and sound quality provided by a multiband single channel noise-reduction algorithm based on the modified Wiener-filter adapted to cochlear implant sound processing. Design: This study was a longitudinal trial with a repeated-measures design. Outcome measures were performed on the first day when the noise reduction feature was provided and after a one month habituation period. Objective measures included pure-tone thresholds and vocal audiometry assessments. Speech perception was measured in quiet and in the presence of two types of noise: a stationary speech shaped noise and a two-talker cocktail noise. Subjective sound quality was assessed using a ten item questionnaire. Study Sample: Thirteen post-lingual deaf adults, experienced users of a cochlear implant system, took part in this study. Results: The noise-reduction algorithm provided a benefit for the perception of speech presented in a stationary speech shaped noise and an overall improvement in subjective sound quality ratings. Conclusions: It was shown that a single channel noise reduction system based on a modified Wiener-filter approach can improve speech in noise perception performance and subjective sound quality in cochlear implant patients.