Correlation between pre-operative CT findings and intra-operative features in pediatric cholesteatoma: a retrospective study on 26 patients.

OBJECTIVE: To assess the predictive value of pre-operative CT imaging in pediatric patients affected by cholesteatoma of the middle ear, comparing pre-operative CT findings to intra-operative features. METHODS: A retrospective study was performed on a population of 26 pediatric patients who underwent tympanoplasty for middle ear cholesteatoma at the Otorhinolaryngology Departments of Verona and Modena University Hospitals between December 2011 and June 2018. Comparison between pre-operative CT images and intra-operative findings (assessed from video recording) was made focusing on the involvement of specific structures: ossicular chain, tegmen tympani, labyrinthine fistula, facial nerve, and temporal bone involvement. CT sensitivity, specificity, positive and negative predictive values were calculated. RESULTS: Overall, 28 surgical procedures were evaluated. No statistically significant differences were encountered between CT images and intra-operatory findings regarding the selected parameters. CONCLUSIONS: Based on our study, pre-operative temporal bone CT scan is a valuable tool for the assessment of pediatric patient candidates for cholesteatoma surgery given the absence of statistically significant differences between radiologic and intra-operative findings. The present findings might support the indication to routinely perform temporal bone CT scan in children with cholesteatoma as part of pre-surgical plan. LEVEL OF EVIDENCE: III.

MP-GeneticSynth: inferring biological network regulations from time series.

MP-GeneticSynth is a Java tool for discovering the logic and regulation mechanisms responsible for observed biological dynamics in terms of finite difference recurrent equations. The software makes use of: (i) metabolic P systems as a modeling framework, (ii) an evolutionary approach to discover flux regulation functions as linear combinations of given primitive functions, (iii) a suitable reformulation of the least squares method to estimate function parameters considering simultaneously all the reactions involved in complex dynamics. The tool is available as a plugin for the virtual laboratory MetaPlab. It has graphical and interactive interfaces for data preparation, a priori knowledge integration, and flux regulator analysis. Availability and implementation: Source code, binaries, documentation (including quick start guide and videos) and case studies are freely available at http://mplab.sci.univr.it/plugins/mpgs/index.html.

Exclusive surgical treatment for vestibular schwannoma regrowth or recurrence: A meta-analysis of the literature.

Vestibular schwannomas can be treated in different ways, but for symptomatic or growing tumors, the gold standard is surgical removal of the lesion. In order to preserve neurovascular structures, partial removal is often performed, leaving a residual that may grow in subsequent years. To date, there is no consensus with regard to surgical treatment of vestibular schwannoma residuals, and so this review focuses on this topic. A structured search was performed on PubMed searching for all articles discussing vestibular schwannoma residuals and recurrences. Only articles discussing surgical treatment were included, focusing on studies which also examined facial nerve outcomes. A total of 51 articles were eligible for review and these included 375 patients. Statistical analysis was performed by correlating the following parameters: patients' gender and age at first surgery, surgical approach adopted at first and subsequent surgeries, tumor and residual size, and extent of resection (gross total, near total, subtotal or others) at first and subsequent surgical procedures. Facial nerve function was also analyzed focusing on its performance when correlated with the different surgical approaches. The data were analyzed by linear regression but there were no correlations between any of the parameters chosen. There was a statistically significant difference between the first approach used (mainly the retrosigmoid route) compared with subsequent approaches (mainly the translabyrinthine route). In total, 8.5 % of patients needed further treatment due to residual regrowth. Facial nerve outcome was independent of the parameters chosen. Exclusive surgical treatment for vestibular schwannoma residuals had a very low failure rate in terms of requiring further treatment. The approach usually chosen for second surgery was the translabyrinthine technique, and this may be explained by the location of the residual, rather than its size. The choice of a particular surgical approach rather than another had no influence on facial nerve function. Complications rates are comparable to Gamma Knife Radiosurgery's as reported in the literature.

Structure/function relationships of phospholipases C Beta.

Phospholipases C beta (PLC-ßs) are essential components of the signal transduction of metazoans. They catalyze the production of the second messengers inositol-1,4,5-trisphosphate (IP3) and diacylglycerol (DAG) from the hydrolysis of phosphatidylinositol-4,5-bisphosphate (PIP2). These enzymes are activated by G-protein-coupled receptors (GPCRs) through the interaction with the alpha subunit of heterotrimeric G-proteins belonging to the Gq family (Gαq), the Gßγ subunits released by the inhibitory G-protein (Gi) and Ca2+ ions. Here we review current structural insights on these important proteins, with a particular focus on the most structurally characterized isoform (PLC-ß3) and the activation mechanism operated by Gαq. We propose, following the lead of recent studies, that a tight combination of experiments and molecular simulations are instrumental in further enlightening the structure/function understanding of PLC-ßs.