STANDARDIZED ELECTROMYOGRAPHIC ANALYSIS OF SWALLOWING AND CLINICAL APPLICATIONS.

BACKGROUND AND AIMS. Swallowing is a complex function which needs coordination between all the structures involved. To date a non-invasive method for the instrumental evaluation of oro-pharyngeal phase of swallowing is lacking. The aims of this study were: phase 1) to develop an electromyographical (EMG) protocol for the assessment of submental muscles (SM), to demonstrate its repeatability and to apply it to maximal voluntary clench (MVC), to quantify the relative contribution of SM; phase 2) to electromyographically analyse the oropharyngeal phase of swallowing finding a standardized and repeatable protocol, to find the physiological muscular pattern involved and to draw the standard model. MATERIALS AND METHODS. In 20 healthy subjects, aged 19-35 years, surface electromyography of SM, masseter (MM) and anterior temporalis (TA) muscles was performed; for phase 1, during maximal voluntary clenching (MVC) with and without cotton rolls and the pushing of the tongue against the palate, while for phase 2 during swallowing. Clenching on cotton rolls and pushing the tongue against the palate were used to standardise respectively MM and TA, and SM muscular potentials. Both phases were repeated in two appointments (T1-T2); submental muscles standardisation (during phase 1) and swallowing (during phase 2) were also repeated twice (A-B) in each session to assess repeatability. RESULTS. Phase 1: symmetry and activity were calculated for each couple of muscles. A two-way analysis of variance was computed for SM: no Factor 1 (T1 vs T2) or Factor 2 (A vs B) or F1 X F2 significant effects were found. SM recruitment was 31% of the maximal activity, with symmetry values larger than 80%. Phase 2: symmetry, activity and duration of activation for each couple of muscles were detected. In addition the duration of the whole exercise and the time of the maximal spike of activation for each muscle were evaluated. A two-way analysis of variance similar to the one of phase 1 was computed : no Factor 1 (T1 vs T2) or Factor 2 (A vs B) or F1 X F2 significant effects were found. Symmetry values were close to 80% for all the muscles, recruitment values were between 22 and 28% of the maximal activity for all the muscles with differences between all the muscles (the MM were the less recruited, while the TA were the most activated). Also the duration of activation of each couple of muscles resulted to be different between all the couples, the MM showed the shortest activation (an average value of approximately 1 s), while the submental muscles the longest one (an average value of more than 1.5 s). The duration of the whole swallowing was found to be between 1.5 and 2 s. Finally, the results showed that all the couples of muscles had their spike of activation between 35.87 and 42.65% of their total duration of activation. The sEMG graphic assessment of the position of the spike was reliable (two-way analysis of variance). CONCLUSIONS. The protocol demonstrated a high repeatability of the EMG indexes both intra and inter-appointment for MVC. Regarding swallowing it is reported that the protocol was repeatable for all the analysed indexes, although an high inter-individual variability. These results are probably due to the existence of different physiological models of swallowing among healthy population

Standardised surface electromyography allows effective submental muscles assessment

The aims of this pilot study were to evaluate: (i) the reproducibility and variability of an electromyographical protocol developed for the assessment of submental muscles (SM) (ii) to apply the new protocol to maximal teeth clenching, a simple and largely studied static task in order to quantify the relative contribution of submental muscles. In 20 healthy subjects, aged 19-35years, surface electromyography of SM, masseter (MM) and anterior temporalis (TA) muscles was performed during maximal voluntary clenching (MVC) with and without cotton rolls and the pushing of the tongue against the palate. Clenching on cotton rolls and pushing the tongue against the palate were used to standardise respectively MM and TA, and SM muscular potentials. The exercises were repeated in two appointments (T1-T2); submental muscles standardisation was also repeated twice (A-B) in each session to assess repeatability. Symmetry and activity were calculated for each couple of muscles. A two-way analysis of variance was computed for SM: no Factor 1 (T1 vs T2) or Factor 2 (A vs B) or F1 7F2 significant effects were found. SM recruitment was 31% of the maximal activity, with symmetry values larger than 80%. In conclusion, standardised electromyography allows a reliable assessment of Submental muscles activity

FLT3 mutational analysis in acute myeloid leukemia: Advantages and pitfalls with different approaches

FMS-like tyrosine kinase 3 (FLT3) is one of the most closely studied genes in blood diseases. Numerous methods have been adopted for analyses, mainly in acute myeloid leukemia (AML) diagnostic work-up. According to international recommendations, the current gold standard approach allows FLT3 canonical mutations to be investigated, providing the main information for risk assessment and treatment choice. However, the technological improvements of the last decade have permitted “black side” gene exploration, revealing numerous hidden aspects of its role in leukemogenesis. The advent of the next-generation sequencing era emphasizes lights and shadows of FLT3 conventional mutational analysis, highlighting the need for a more comprehensive study of the gene. However, more extensive analysis is opening new, unexplored questions whose impact on clinical outcomes is still unknown. The present work is focused on the main topics regarding FLT3 mutational analysis in AML, debating the strengths and weaknesses of the current gold standard approach. The rights and wrongs of NGS introduction in clinical practice will be discussed, showing that a more extensive knowledge of FLT3 mutational status could lead to reconsidering its role in AML management

Inside the biology of early T-cell precursor acute lymphoblastic leukemia: the perfect trick

Early T-cell precursor acute lymphoblastic leukemia (ETP-ALL) is a rare, distinct subtype of T-ALL characterized by genomic instability, a dismal prognosis and refractoriness to standard chemotherapy. Since its first description in 2009, the expanding knowledge of its intricate biology has led to the definition of a stem cell leukemia with a combined lymphoid-myeloid potential: the perfect trick. Several studies in the last decade aimed to better characterize this new disease, but it was recognized as a distinct entity only in 2016. We review current insights into the biology of ETP-ALL and discuss the pathogenesis, genomic features and their impact on the clinical course in the precision medicine era today

Can the new and old drugs exert an immunomodulatory effect in acute myeloid leukemia?

Acute myeloid leukemia (AML) is considered an immune-suppressive neoplasm capable of evading immune surveillance through cellular and environmental players. Increasing knowledge of the immune system (IS) status at diagnosis seems to suggest ever more attention of the crosstalk between the leukemic clone and its immunologic counterpart. During the last years, the advent of novel immunotherapeutic strategies has revealed the importance of immune dysregulation and suppression for leukemia fitness. Considering all these premises, we reviewed the “off-target” effects on the IS of different drugs used in the treatment of AML, focusing on the main advantages of this interaction. The data reported support the idea that a successful therapeutic strategy should consider tailored approaches for performing leukemia eradication by both direct blasts killing and the engagement of the IS

Dielectric behavior of biopolymer based composites containing multi wall carbon nanotubes: Effect of filler content and aspect ratio

Multi wall carbon nanotubes (MWCNTs) with different aspect ratios (30, 105 and 667) were included in a commercial fully biodegradable blend using melt mixing. Samples of composite systems prepared by hot molding and containing up to 1.2 vol% of MWCNTs were studied by means of DC electrical resistivity and dielectric spectroscopy in order to enhance effect of filler content and aspect ratio on their dielectric behavior. Raman spectroscopic investigations and morphological observations were also performed in order to correlate dielectric behavior with surface carbon nanotubes features and to check the actual level of dispersion of carbon nanotubes under the applied processing conditions. Results emphasized that the carbon nanotubes aspect ratio and their surface regularity determine the electrical properties of composites because they strongly influence percolation thresholds, dielectric permittivity and dissipation factor of produced materials. A satisfying dispersion of the filler seems to be achieved under the employed processing conditions. These preliminary results demonstrates possible applications of this type of biobased systems in many applications going from stress control to devices for high storage energy

Imatinib-mesylate for all patients with hypereosinophilic syndrome?

Some recent papers have focused on the activity of imatinib-mesylate, a selective inhibitor of tyrosine kinase, in idiopathic hypereosinophilic syndrome (HES) [1], [2], [3] and [4]. In this setting, a possible therapeutic target was identified by Cools et al. [2], who described the fusion tyrosine-kinase gene FIP1L1/PDGFRA as the result of an interstitial deletion within chromosome 4 in nine out of sixteen (56%) patients affected by HES. Of interest, although in this study the response to imatinib was strictly correlated with the presence of FIP1L1/PDGFRA rearrangement (all patients with such a molecular lesion treated with imatinib responded), only five out of nine responding patients evidenced the abnormal transcript [2]. Among the possible alternative mechanisms for the activation of the PDGFRA tyrosine-kinase domain, these authors suggested there may be a different fusion gene