Finite mixture clustering of human tissues with different levels of IGF-1 splice variants mRNA transcripts

BACKGROUND: This study addresses a recurrent biological problem, that is to define a formal clustering structure for a set of tissues on the basis of the relative abundance of multiple alternatively spliced isoforms mRNAs generated by the same gene. To this aim, we have used a model-based clustering approach, based on a finite mixture of multivariate Gaussian densities. However, given we had more technical replicates from the same tissue for each quantitative measurement, we also employed a finite mixture of linear mixed models, with tissue-specific random effects. RESULTS: A panel of human tissues was analysed through quantitative real-time PCR methods, to quantify the relative amount of mRNA encoding different IGF-1 alternative splicing variants. After an appropriate, preliminary, equalization of the quantitative data, we provided an estimate of the distribution of the observed concentrations for the different IGF-1 mRNA splice variants in the cohort of tissues by employing suitable kernel density estimators. We observed that the analysed IGF-1 mRNA splice variants were characterized by multimodal distributions, which could be interpreted as describing the presence of several sub-population, i.e. potential tissue clusters. In this context, a formal clustering approach based on a finite mixture model (FMM) with Gaussian components is proposed. Due to the presence of potential dependence between the technical replicates (originated by repeated quantitative measurements of the same mRNA splice isoform in the same tissue) we have also employed the finite mixture of linear mixed models (FMLMM), which allowed to take into account this kind of within-tissue dependence. CONCLUSIONS: The FMM and the FMLMM provided a convenient yet formal setting for a model-based clustering of the human tissues in sub-populations, characterized by homogeneous values of concentrations of the mRNAs for one or multiple IGF-1 alternative splicing isoforms. The proposed approaches can be applied to any cohort of tissues expressing several alternatively spliced mRNAs generated by the same gene, and can overcome the limitations of clustering methods based on simple comparisons between splice isoform expression levels

From Super-Participants to Super-Echoed. Participation in the 2018 Italian Electoral Twittersphere

Who and how takes part in a typical Twitter discussion about political elections? In what degree? In our study we try to shed some light on these questions by examining the case of Italian 2018 national election. Starting from the database that we collected during the latest general campaign, we analyse all the users who participated in the discussion unfolding in the two months preceding the vote. To do that, we exploit the concept of super-participants isolating the 1% of users who generate large part of the discussion. We study them identifying the two main participation flows in the Twittersphere generated by tweets and retweets, discovering that participation curves are very skewed. To address issues of centrality and inclusiveness in online communication, we look at who the super-participants are in the broader society, finding that many of them are citizens. To inquire if participation draws attention, we identify a set of super-echoed users discovering that, belonging to élite categories is still an advantage given that starting popularity is often more important to be shared than participation. In fact, citizens’ super-participation is not mirrored by an equally consistent received attention. Notwithstanding, political supporters and satirical blogs emerge to be two very interesting categories

Il framing dell’elezione del Presidente della Repubblica: processi di ibridazione tra Televisione, Twitter e Stampa quotidiana

L’attuale narrazione della politica sembra sempre più passare attraverso un processo di triangolazione tra Televisione, Twitter e Carta Stampata (Bentivegna, Marchetti, 2014), in cui attori tradizionali e non contribuiscono alla definizione dei frame dell’agenda pubblica. In questo contesto, risulta molto più complesso rispondere ad alcune domande classiche dell’agenda setting (Neumann, 2014), non solo su chi decide l’ordine di priorità dell’agenda, ma anche su quali attori incidono sul framing delle issue e con quali modalità. Tali questioni si fanno tanto più urgenti, in un ecosistema informativo attraversato da processi di ibridazione multipli (Chadwick, 2011) in cui la Social TV sembra emergere come pratica spesso volta alla ridefinizione dei frame interpretativi attraverso l’uso contemporaneo del second screen (Bentivegna, 2014). L’obiettivo della ricerca è stato l’esplorazione delle modalità di costruzione e di diffusione dei frame (Entman, 1993; Marini, 2006) di una issue politica in un contesto di ibridazione dell’ecosistema mediale

Attention deficit hyperactivity disorder: A pilot study for symptom assessment and diagnosis in children in Chile

Background: Attention Deficit Hyperactivity Disorder (ADHD) is one of the most prevalent psychiatric disorders among school-age children and is characterized by varying degrees of inattention, hyperactivity, and impulsivity. Diagnosis, which currently relies on the DSM-V criteria, is complex. This research proposes an integrated procedure for ADHD diagnosis in children, improving the diagnostic process and scientific research on etiopathology. Materials and methods: We conducted a clinical report on ADHD diagnosis in children (n = 92) between the ages of 8 and 13, based on the results of the application of different scales to parents of school-age children in Chile. The children were divided into two groups, those with an ADHD diagnosis (n = 44) and those without (n = 48) (24% females). Results: The results revealed statistically significant differences between groups for scales EDAH y SDQ-Cas, Conners Comprehensive Behavior Scale, Conners Parent Scale and the criteria according to the DSM-V and its dimensions, with the exception of inattention. Conclusion: The findings indicate the importance of appropriate criteria and procedures to establish a diagnosis and implement effective interventions in ADHD

Oxidative stress and synaptic dysfunction in rodent models of Parkinson's disease

Parkinson's disease (PD) is a multifactorial disorder involving a complex interplay between a variety of genetic and environmental factors. In this scenario, mitochondrial impairment and oxidative stress are widely accepted as crucial neuropathogenic mechanisms, as also evidenced by the identification of PD-associated genes that are directly involved in mitochondrial function. The concept of mitochondrial dysfunction is closely linked to that of synaptic dysfunction. Indeed, compelling evidence supports the role of mitochondria in synaptic transmission and plasticity, although many aspects have not yet been fully elucidated. Here, we will provide a brief overview of the most relevant evidence obtained in different neurotoxin-based and genetic rodent models of PD, focusing on mitochondrial impairment and synaptopathy, an early central event preceding overt nigrostriatal neurodegeneration. The identification of early deficits occurring in PD pathogenesis is crucial in view of the development of potential disease-modifying therapeutic strategies

Coronavirus–associated enteritis in a quail farm

An enteric syndrome observed in semi-intensively reared quails is described. The affected birds showed depression, severe diarrhoea and dehydration. The mortality occurred particularly in young birds. At necropsy, the prominent lesion was catarrhal enteritis. Laboratory investigations demonstrated the presence of coronavirus in the gut of dead animals. No additional pathogens were detected. To our knowledge, this is the first evidence for the presence of CoVs in quail with enteritis

Le «tweeting habit» dei media outlet italiani. Strategie di comunicazione in un ecosistema mediale ibrido

The article explores the online strategies adopted by the Italian media organizations in order to adapt to the new hybrid media system. The research has focused on the Twitter profiles and timelines of 28 Italian companies, including news agencies, newspapers, TV news and online news. The concept of tweeting habit has been considered paying attention to four different dimensions: productivity of the account, competence of use, audience engagement capacity, predisposition to interaction. The principal component and cluster analysis we carried show that media outlets follow an highly diverse spectrum of strategies mixing broadcast and conversational models and being characterized by more or less competent approaches to the platform. On this basis, we propose a typology allowing to describe the different groups of media outlets we studied as: traditional gatekeepers, «wannabe» gatekeepers, and gatewatchers. The media outlets in the latter group show a better performance when it comes to audience engagement

Down Regulation of High in Normal-1 (<b> <i>HIN-1</i> </b>) is a Frequent Event in Stage I Non-Small Cell Lung Cancer and Correlates with Poor Clinical Outcome

Abstract Purpose: The aim of this study was to evaluate the prevalence and the clinical significance of HIN-1 mRNA expression in early stage non-small cell lung carcinomas (NSCLCs). Experimental Design: A series of 91 NSCLC patients with stage I neoplastic disease was studied. HIN-1 expression was investigated by quantitative real-time reverse transcription-PCR on tumor specimens and matching normal lung tissues. Variables were analyzed by χ2 test and Fisher's exact tests. Survival was evaluated with the method of Kaplan-Meier. Multivariate analysis was performed with Cox's proportional hazards model. Results: Seventy one (78%) tumors showed a reduction of HIN-1 mRNA compared with the normal counterpart. The range of reduction varied greatly, from −2-fold to −3350-fold. Setting a cutoff at −46-fold (median value of HIN-1 mRNA reduction), 46 cases (51%) had a markedly reduced expression, and 45 cases (49%) showed a normal or slightly reduced expression. A statistically significant association between low HIN-1 mRNA levels and T status was observed (P = 0.036). Univariate survival curves, estimated using the method of Kaplan-Meier, defined a significant association between HIN-1 expression and both overall survival (P = 0.0095) and disease-free survival (P = 0.0122). A multivariate analysis, performed by Cox's proportional hazards regression model, confirmed that a low HIN-1 expression was the only significant factor to predict poor prognosis. Conclusions: Our data indicate that HIN-1 expression, measured by real-time reverse transcription-PCR, is a possible prognostic factor in patients with stage I NSCLC. Additional studies are required to further validate this potential prognostic marker

Centrality of Striatal Cholinergic Transmission in Basal Ganglia Function

Work over the past two decades revealed a previously unexpected role for striatal cholinergic interneurons in the context of basal ganglia function. The recognition that these interneurons are essential in synaptic plasticity and motor learning represents a significant step ahead in deciphering how the striatum processes cortical inputs, and why pathological circumstances cause motor dysfunction. Loss of the reciprocal modulation between dopaminergic inputs and the intrinsic cholinergic innervation within the striatum appears to be the trigger for pathophysiological changes occurring in basal ganglia disorders. Accordingly, there is now compelling evidence showing profound changes in cholinergic markers in these disorders, in particular Parkinson's disease and dystonia. Based on converging experimental and clinical evidence, we provide an overview of the role of striatal cholinergic transmission in physiological and pathological conditions, in the context of the pathogenesis of movement disorders