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Trova, S.

Publications and source records attributed to Trova, S..

4 recordsLinked to original sources

GeNePi: a GPU-enhanced Next Generation Bioinformatics Pipeline for Whole Genome Sequencing Analysis

Next Generation Sequencing (NGS) has revolutionized genome biology, enabling the rapid sequencing of an entire human genome and facilitating the integration of Whole Genome Sequencing (WGS) into both research and clinical applications. The high-throughput nature of NGS and the complex data processing required has driven the need for advanced computational infrastructures to analyse these large datasets. The aim of this work is to introduce an innovative bioinformatic pipeline, named GeNePi, for the efficient and precise analysis of WGS short paired-end reads. Built on the Nextflow framework with a modular structure, GeNePi incorporates GPU-accelerated algorithms and supports multiple work-flow configurations. The pipeline automates the extraction of biologically relevant insights from raw WGS data, including: disease-related variants such as single nucleotide variants (SNVs), small insertions or deletions (INDELs), copy number variants (CNVs), and structural variants (SVs). Optimized for high-performance computing (HPC) environments, it takes advantage of job-scheduler submissions, parallelised processing, and tailored resource allocation for each analysis step. Tested on synthetic and real datasets, GeNePi accurately identifies genomic variants, with performances comparable to that of state-of-art tools. These features make GeNePi a valuable instrument for large-scale analyses in both research and clinical contexts, representing a key step towards the establishment of National Centers for Computational and Technological Medicine.

bioinformatics↗

A highly contiguous reference genome for the Alpine ibex (Capra ibex)

Species conservation efforts can be threatened by deleterious mutation accumulation following population contractions. In addition to de novo mutations, a significant source of genetic load could be deleterious variants introduced into a population through hybridization. Hence, even successfully restored species may face deleterious mutation swamping due to hybridization with an abundant and closely related species. The outcomes of such hybridization events are poorly understood given the complex interplay of introduced adaptive and maladaptive variation. Here, we analyze this potential risk for Alpine ibex (Capra ibex), a flagship species of large mammal restoration in the Alps. Near-extinction two centuries ago resulted in exceptionally low genome-wide diversity and increased inbreeding, which facilitated the purging of severe deleterious mutations but accumulation of less severe ones. We produced a highly contiguous chromosome-level genome assembly of the Alpine ibex capturing structural divergence from its closest domestic species, the domestic goat (Capra hircus) known to hybridize with Alpine ibex Genome sequencing of eight recent ibex-goat hybrids and backcrosses from two hybrid swarms in Northern Italy revealed highly diverse recombinants and an average of 30 masked, predicted loss-of-function (LOF) mutations per hybrid compared to 10 in non-hybrid Alpine ibex. This exposes Alpine ibex to further backcrosses, exposing their vulnerable gene pool to an influx of hybridization load. Individual-based genomic simulations suggest that such LOF load would return to pre- hybridization levels with a lag of over 100 generations after gene flow subsides. Hybridization could also disrupt local adaptation in the recipient species. Our work provides a direct estimate of hybridization load and, by this, informs on the complexity of managing endangered gene pools in the face of hybridization.

evolutionary biology↗

Pathogen and human NDPK-proteins promote AML cell survival via monocyte NLRP3-inflammasome activation.

A history of infection has been linked with increased risk of acute myeloid leukaemia (AML) and related myelodysplastic syndromes (MDS). Furthermore, AML and MDS patients suffer frequent infections because of disease-related impaired immunity. However, the role of infections in the development and progression of AML and MDS remains poorly understood. We and others previously demonstrated that the human nucleoside diphosphate kinase (NDPK) NM23-H1 protein promotes AML blast cell survival by inducing secretion of IL-1{beta} from accessory cells. NDPKs are an evolutionary highly conserved protein family and pathogenic bacteria secrete NDPKs that regulate virulence and host-pathogen interactions. Here, we demonstrate the presence of IgM antibodies against a broad range of pathogen NDPKs and more selective IgG antibody activity against pathogen NDPKs in the blood of AML patients and normal donors, demonstrating that in vivo exposure to NDPKs likely occurs. We also show that pathogen derived NDPK-proteins faithfully mimic the catalytically independent pro-survival activity of NM23-H1 against primary AML cells. Flow cytometry identified that pathogen and human NDPKs selectively bind to monocytes in peripheral blood. We therefore used vitamin D3 differentiated monocytes from wild type and genetically modified THP1 cells as a model to demonstrate that NDPK-mediated IL-1{beta} secretion by monocytes is NLRP3-inflammasome and caspase 1 dependent, but independent of TLR4 signaling. Monocyte stimulation by NDPKs also resulted in activation of NF-{kappa}B and IRF pathways but did not include the formation of pyroptosomes or result in pyroptotic cell death which are pivotal features of canonical NLRP3 inflammasome activation. In the context of the growing importance of the NLRP3 inflammasome and IL-1{beta} in AML and MDS, our findings now implicate pathogen NDPKs in the pathogenesis of these diseases. Author SummaryAcute myeloid leukaemia (AML) and myelodysplastic syndromes MDS) are related blood cancers that are associated with frequent infections because the cancers suppress normal immunity. These infections are therefore generally considered as medical complications arising as a result of but separate to the cancer. However, we provide evidence here that infections may promote or drive cancer progression. We and others previously demonstrated that a human protein called NM23-H1 promotes the survival of AML cells by eliciting survival signals from other cells. NM23-H1 belongs to a highly conserved family of proteins that also occur in bacteria and fungi that cause infections in AML and MDS patients. Here we demonstrate that these bacterial and fungal proteins recapitulate the pro-survival effect of NM23-H1 on AML cells. We also determine that these effects are mediated via mechanisms already known to be important in the development and progression of AML and MDS. This study is the first to identify NM23-H1 like proteins from pathogenic microorganisms as novel activators of these pathways. These findings have important implications for how we understand infections in AML and MDS patients and suggest that in addition to being the consequence of these diseases, infections may also drive the cancer process.

microbiology↗

Decrease of Functional Connectivity within the Default Mode Network by a Brief Training of Focused Attention on the Breath in Novices

Experienced meditators reduce the activity of the default mode network (DMN), a brain system preferentially active when people are not engaged in specific tasks. However, the neural modulation of the DMN in novices remain largely unexplored. By using electroencephalography, we investigated the DMN functional connectivity in two groups of novices: the meditation group practiced six consecutive days of focused attention on the breath; the control group practiced only on the first and last days. After the brief training, results showed a decrease in the DMN functional connectivity between the ventromedial prefrontal cortex and the posterior cingulate cortex in theta and alpha bands during the focused attention condition, in the meditation group compared to the control group. The change in DMN functional connectivity was significantly correlated with the increase in state-level mindfulness scores. These data elucidate DMN modifications already arising at the initial stages of mindfulness meditation training in novices.

neuroscience↗