Nasal Microbiota in RSV Bronchiolitis

Respiratory Syncytial Virus (RSV) is the leading cause of bronchiolitis, and the severity may be influenced by the bacterial ecosystem. Our aim was to analyze the nasal microbiota from 48 infants affected by bronchiolitis from RSV virus and 28 infants with bronchiolitis but negative for the virus. Results showed a significantly lower biodiversity in the RSV-positive group with respect to the RSV-negative group, a specific microbial profile associated with the RSV-positive group different from that observed in the negative group, and significant modifications in the relative abundance of taxa in the RSV-positive group, as well as in the RSV-A group, with respect to the negative group. Furthermore, microbial network analyses evidenced, in all studied groups, the presence of two predominant sub-networks characterized by peculiar inter- and intra-group correlation patterns as well as a general loss of connectivity among microbes in the RSV-positive group, particularly in the RSV-A group. Our results indicated that infants with more severe bronchiolitis disease, caused by RSV-A infection, present significant perturbations of both the nasal microbiota structure and the microbial relationships. Patients with a milder bronchiolitis course (RSV-B-infected and patients who have cleared the virus) presented less severe alterations

16S metagenomics reveals dysbiosis of nasal core microbiota in children with chronic nasal inflammation: role of adenoid hypertrophy and allergic rhinitis

Allergic rhinitis (AR) and adenoid hypertrophy (AH) are, in children, the main cause of partial or complete upper airway obstruction and reduction in airflow. However, limited data exist about the impact of the increased resistance to airflow, on the nasal microbial composition of children with AR end AH. Allergic rhinitis (AR) as well as adenoid hypertrophy (AH), represent extremely common pathologies in this population. Their known inflammatory obstruction is amplified when both pathologies coexist. In our study, the microbiota of anterior nares of 75 pediatric subjects with AR, AH or both conditions, was explored by 16S rRNA-based metagenomic approach. Our data show for the first time, that in children, the inflammatory state is associated to similar changes in the microbiota composition of AR and AH subjects respect to the healthy condition. Together with such alterations, we observed a reduced variability in the between-subject biodiversity on the other hand, these same alterations resulted amplified by the nasal obstruction that could constitute a secondary risk factor for dysbiosis. Significant differences in the relative abundance of specific microbial groups were found between diseased phenotypes and the controls. Most of these taxa belonged to a stable and quantitatively dominating component of the nasal microbiota and showed marked potentials in discriminating the controls from diseased subjects. A pauperization of the nasal microbial network was observed in diseased status in respect to the number of involved taxa and connectivity. Finally, while stable co-occurrence relationships were observed within both control- and diseases-associated microbial groups, only negative correlations were present between them, suggesting that microbial subgroups potentially act as maintainer of the eubiosis state in the nasal ecosystem. In the nasal ecosysteminflammation-associated shifts seem to impact the more intimate component of the microbiota rather than representing the mere loss of microbial diversity. The discriminatory potential showed by differentially abundant taxa provide a starting point for future research with the potential to improve patient outcomes. Overall, our results underline the association of AH and AR with the impairment of the microbial interplay leading to unbalanced ecosystems

STUDIO BIOMECCANICO E IMPLEMENTAZIONE ROBOTICA DEL MOVIMENTO DELLE GAMBE NEL NUOTO

Nel presente lavoro è stato analizzato e, successivamente, implementato, sulla piattaforma robotica SABIAN (Sant’Anna BIped humANoid), il movimento natatorio umano di flutter kick (o pinneggiata). Per lo studio del movimento è stato definito un modello cinematico, sulla base della convenzione di Denavit-Hartenberg, e, data la complessità delle forze di resistenza e propulsione agenti sul corpo, è stato considerato il modello di simulazione SWUM, sviluppato da Motomu Nakashima et al., per la dinamica. Per l’implementazione sono stati realizzati dei pattern che forniscono, al programma di controllo del robot, i valori degli angoli ai giunti da fare eseguire al robot stesso. Mediate l’ausilio del simulatore SWUM sono state fatte delle prove per valutare l’adeguatezza del robot a muoversi in acqua. Sulla base dei valori degli angoli registrati e delle analisi video delle prove effettuate sulla piattaforma, è possibile affermare che il robot esegue correttamente il movimento richiesto, e, dalle simulazioni, risulta che i pattern definiti corrispondono a un movimento corretto in acqua. Il robot, per la sua attuale struttura, non può ancora muoversi in acqua, ma, ipotizzandolo rivestito da una muta stagna, in modo da poterlo riempire con materiali che permettono di diminuire la densità totale della piattaforma, potrà nuotare. In this work the leg “flutter kick” swimming motion has been studied and then it has been implemented on a humanoid robotic platform, the SABIAN (Sant’Anna BIped humANoid) robot. A kinematic model, based on Denavit-Hartenberg method, has been developed. The SWUM simulator model, developed by Motomu Nakashima et al., has been considered for the dynamics, given the complexity of unsteady forces. Swimming patterns, formed by the values of joint angles, have been developed and values of joint angles have been recorded during the performances. Tests in water have been done using the SWUM simulator with the robot geometry in order to understand if the robot is adequate for implementation in water. From trials swimming patterns can be considered correct. The robot is inadequate for implementation in water presently, due to the configuration, the materials and the density of the humanoid platform. Instead, considering the robot covered by a dry suit and introducing inside materials with a low density, the SABIAN could swim in the water without sinking

A robotic implementation of predictive smooth pursuit eye movement with occlusions

This work is an implementation of the concept of predictive behaviours in robotics and specifically it refers to the idea of EP, Expected Perception, the sensory input predicted and compared with the actual ones to improve perception-action loop

Implementation of a bio-inspired visual tracking model on the iCub robot

The purpose of this work is to investigate the applicability of a visual tracking model on humanoid robots in order to achieve a human-like predictive behavior. In humans, in case of moving targets the oculomotor system uses a combination of the smooth pursuit eye movement and saccadic movements, namely "catch up" saccades to fixate the object of interest This work aims to validate the "catch up" saccade model in order to obtain a human-like tracking system able to correctly switch from a zero-lag predictive smooth pursuit to a fast orienting saccade for the position error compensation. Experimental results on the iCub simulator show several correspondences with the human behavior

A comparison between two bio-inspired adaptive models of Vestibulo-Ocular Reflex (VOR) implemented on the iCub robot

In order to develop efficient bio-inspired sensory-motor control for humanoid robots there are different kind of approaches that can be used to simulate a specific human behavior. The purpose of this work is to compare two models of the Vestibulo-Ocular Reflex (VOR) for the image stabilization during head movements. The VOR system has adaptive properties and this behavior resides in the cerebellum. This adaptive system uses the retinal slip as error signal and compensates for the eye dynamics, the control loop latencies and the nonlinearity due to the offset between the rotational axes of the eyeballs and the head. The adaptation mechanism has been represented by the two models in one case as a Feedback Error Learning (FEL) [1] and in the other as a decorrelation model [2]. In this work it has been shown principal results about the implementation on the simulator of the iCub robot

Efficacy of Pidotimod use in treating allergic rhinitis in a pediatric population

Abstract Background: Allergic rhinitis (AR) and adenoidal hypertrophy (AH) are the most frequent causative disorders of nasal obstruction in children, leading to recurrent respiratory infections. Both nasal cavities are colonized by a stable microbial community susceptible to environmental changes and Staphylococcus aureus seems to play the major role. Furthermore, nasal microbiota holds a large number and variety of viruses with upper respiratory tract infections. This local microbiota deserves attention because its modification could induce a virtuous cross-talking with the immune system, with a better clearance of pathogens. Although AR and AH present a different etiopathogenesis, they have in common a minimal chronic inflammation surrounding nasal obstruction; hence it would be challenging to evaluate the effect of an immunomodulator on this minimal chronic inflammation with possible clinical and microbiological effects. The aim of this study is therefore to evaluate the efficacy of an immunomoldulator (Pidotimod) on nasal obstruction in children with AR and/or AH and whether its action involves a variation of nasal microbiota. Methods: We enrolled 76 children: those with allergic rhinitis (AR) sensitized to dust mites entered the AR group, those with adenoidal hypertrophy (AH) the AH group, those with both conditions the AR/AH group and those without AR ± AH as controls (CTRL). At the first visit they performed: skin prick tests, nasal fiberoptic endoscopy, anterior rhinomanometry, nasal swabs. Children with. AR ± AH started treatment with Pidotimod. After 1 month they were re-evaluated performing the same procedures. The primary outcome was the evaluation of nasal obstruction after treatment and the secondary outcome was the improvement of symptoms and the changes in nasal microflora. Results: All patients improved their mean nasal flow (mNF) in respect to the baseline. In AR children mNF reached that one of CTRL. In AH children±AR the mNF was lower in respect to CTRL and AR group. We did not find any differences among all the groups at the two different time points in nasal microflora. Conclusions: Pidotimod is able to give an improvement in nasal obstruction, especially in AR children but this effect seems to be not mediated by changes in nasal microbiota