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Search Results: 1 - 10 of 3859 matches for " Alessandra Ciccozzi "
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Phylogeny and phylodinamic of Hepatitis C in Italy
Ciccozzi Massimo,Lo Presti Alessandra,Ciccaglione Anna,Zehender Gianguglielmo
BMC Infectious Diseases , 2012, DOI: 10.1186/1471-2334-12-s2-s5
Abstract: Hepatitis C virus infection (HCV) is one of the most pressing health emergencies in the world with a global prevalence of about 170 million people chronically infected worldwide. In Europe, Italy has the highest HCV prevalence (3 - 4.4%) with peaks of 12.6 - 26% in Southern regions and the major islands. In Italy HCV genotype 1b prevails, and genotype 4 is mainly found in the south of the country where the prevalence is particularly high in regions such as Calabria. Phylogenetics analysis is a molecular tool widely used to study rapidly-evolving RNA viruses that establish chronic infections such as HCV. Searching the scientific literature, it was found that thirty-nine genetic studies on HCV genotypes have been carried out in Italy between 1997 to 2012 years. However, phylogenetic analysis was performed only in fourteen out of thirty-nine HCV studies (36%) considered. Monitoring the genetic evolution of HCV is an essential step to control the local as well as global HCV epidemic and to develop efficient preventive and therapeutic strategies.
Hemodynamic Changes during Hepatic Vascular Exclusion: Use of Intraoperative Transesophageal Echocardiography a Case Series
Franco Marinangeli,Alessandra Ciccozzi,Chiara Angeletti,Cristiana Guetti
ISRN Anesthesiology , 2011, DOI: 10.5402/2011/278545
Abstract:
Human polyomaviruses identification by logic mining techniques
Emanuel Weitschek, Alessandra Lo Presti, Guido Drovandi, Giovanni Felici, Massimo Ciccozzi, Marco Ciotti, Paola Bertolazzi
Virology Journal , 2012, DOI: 10.1186/1743-422x-9-58
Abstract: The approach presented in this work is successful as it discovers several logic rules that effectively characterize the different five studied polyomaviruses. The individuated logic rules are able to separate precisely one viral type from the other and to assign an unknown DNA sequence to one of the five analyzed polyomaviruses.The data mining analysis is performed by considering the complete sequences of the viruses and the sequences of the different gene regions separately, obtaining in both cases extremely high correct recognition rates.Phylogenetic analysis is a technique used to perform species classification through DNA sequences analysis [1]. It examines sequence divergence or similarity through the alignment of DNA sequences. Recently, a new technique, named logic data mining, has been introduced and applied in species classification through DNA barcode, a short fragment of mitochondrial DNA composed of few hundreds of bases from which it is possible to extract the information needed to classify living species [2]. This technique allows finding patterns of nucleotides in the DNA barcode of a given species that characterizes it and allows distinguishing one species from the others. A pattern is defined as a set of positions of the DNA sequence whose corresponding nucleotides completely characterize the species. The logic data mining technique provides a sort of fingerprinting of the species and has been shown to allow a correct classification of new individuals. In this work we apply this technique to the classification of polyomaviruses. Human polyomaviruses are small double stranded DNA viruses of about 5 kb in length which belong to the Polyomaviridae family. Up to 2008, five human polyomaviruses have been identified and characterized: BK (BKPyV), JC (JCPyV), KI (KIPyV), WU (WUPyV) and MC (MCPyV) polyomaviruses. BKPyV and JCPyV were both uncovered in 1971. BKPyV was first identified in the urine of a kidney transplant patient [3], while JCPyV was uncovered
A computational approach to identify point mutations associated with occult hepatitis B: significant mutations affect coding regions but not regulative elements of HBV
Roberto Bruni, Mattia Prosperi, Cinzia Marcantonio, Alessandra Amadori, Umbertina Villano, Elena Tritarelli, Alessandra Presti, Massimo Ciccozzi, Anna R Ciccaglione
Virology Journal , 2011, DOI: 10.1186/1743-422x-8-394
Abstract: 41 OBI and 162 non-OBI complete genome sequences were retrieved from GenBank, aligned and subjected to univariable analysis including statistical evaluation. Their S coding region was analyzed for Stop codon mutations too, while S amino acid variability could be evaluated for genotype D only, due to the too small number of available complete genome OBI sequences from other genotypes.Prediction models were derived by multivariable analysis using Logistic Regression, Rule Induction and Random Forest approaches, with extra-sample error estimation by Multiple ten-fold Cross-Validation (MCV). Models were compared by t-test on the Area Under the Receiver Operating Characteristic curve (AUC) distributions obtained from the MCV runs for each model against the best-performing model.Variations in seven nucleotide positions were significantly associated with OBI, and occurred in 11 out of 41 OBI sequences (26.8%): likely, other mutations did not reach statistical significance due to the small size of OBI dataset. All variations affected at least one HBV coding region, but none of them mapped to regulative elements. All viral proteins, with the only exception of the X, were affected. Stop codons in the S, that might account for absence of serum HBsAg, were not significantly enriched in OBI sequences. In genotype D, amino acid variability in the S was higher in OBI than non-OBI, particularly in the immunodominant region. A Random Forest prediction model showed the best performance, but all models were not satisfactory in terms of specificity, due to the small sample size of OBIs; however results are promising in the perspective of a broader dataset of complete genome OBI sequences.Data suggest that point mutations rarely occur in regulative elements of HBV, if ever, and contribute to OBI by affecting different viral proteins, suggesting heterogeneous mechanisms may be responsible for OBI, including, at least in genotype D, an escape mutation mechanism due to imperfect immune con
Within-Host Dynamics of the Hepatitis C Virus Quasispecies Population in HIV-1/HCV Coinfected Patients
Flavia Bernini,Erika Ebranati,Chiara De Maddalena,Renata Shkjezi,Laura Milazzo,Alessandra Lo Presti,Massimo Ciccozzi,Massimo Galli,Gianguglielmo Zehender
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0016551
Abstract: HIV/HCV coinfected individuals under highly active antiretroviral therapy (HAART) represent an interesting model for the investigation of the role played by the immune system in driving the evolution of the HCV quasispecies. We prospectively studied the intra-host evolution of the HCV heterogeneity in 8 coinfected subjects, selected from a cohort of 32 patients initiating HAART: 5 immunological responders (group A) and 3 immunological non-responders (group B), and in two HCV singly infected controls not assuming drugs (group C). For all these subjects at least two serial samples obtained at the first observation (before HAART) and more than 1 year later, underwent clonal sequence analysis of partial E1/E2 sequences, encompassing the whole HVR1. Evolutionary rates, dated phylogenies and population dynamics were co-estimated by using a Bayesian Markov Chain Monte Carlo approach, and site specific selection pressures were estimated by maximum likelihood-based methods. The intra-host evolutionary rates of HCV quasispecies was 10 times higher in subjects treated with HAART than in controls without immunodeficiency (1.9 and 2.3×10?3 sub/site/month in group A and B and 0.29×10?3 sub/site/month in group C individuals). The within-host Bayesian Skyline plot analysis showed an exponential growth of the quasispecies populations in immunological responders, coinciding with a peak in CD4 cell counts. On the contrary, quasispecies population remained constant in group B and in group C controls. A significant positive selection pressure was detected in a half of the patients under HAART and in none of the group C controls. Several sites under significant positive selection were described, mainly included in the HVR1. Our data indicate that different forces, in addition to the selection pressure, drive an exceptionally fast evolution of HCV during HAART immune restoration. We hypothesize that an important role is played by the enlargement of the viral replicative space.
GlideScope and Frova Introducer for Difficult Airway Management
Alessandra Ciccozzi,Chiara Angeletti,Cristiana Guetti,Roberta Papola,Paolo Matteo Angeletti,Antonella Paladini,Giustino Varrassi,Franco Marinangeli
Case Reports in Anesthesiology , 2013, DOI: 10.1155/2013/717928
Abstract: The introduction into clinical practice of new tools for intubation as videolaringoscopia has dramatically improved the success rate of intubation and the work of anesthesiologists in what is considered the most delicate maneuver. Nevertheless intubation difficulties may also be encountered with good anatomical visualization of glottic structures in videolaringoscopia. To overcome the obstacles that may occur both in a difficult provided intubation such as those unexpected, associated endotracheal introducer able to facilitate the passage of the endotracheal tube through the vocal cords into the trachea may be useful. We report 4 cases of difficult intubation planned and unplanned and completed successfully using the GlideScope videolaryngoscope associated with endotracheal Frova introducer. 1. Introduction Difficult airway management is a major task for anesthesiologists [1, 2]. Failure in airway management indeed, is a major cause of mortality and morbidity in the setting of anesthesiology and intensive care units [3, 4]. The GlideScope (GS) is a videolaryngoscope (VLS), the last generation of intubation devices available in clinical practice in the last decade. GS provides an indirect airway view, improves the assessment of Cormack-Lehane score, and does not require a specific training [5, 6]. Recent studies underline the advantages of VLS in the management of predicted difficult airway [7, 8] as well as prehospital emergencies [9]. Unfortunately, the direct laryngeal view provided by VLS does not always assure the correct insertion of endotracheal tube (ETT), due to the 60-degree angle in the distal portion of GS blade, that tends to hamper the passage of the ETT from oropharynx to trachea. To facilitate the placement of the ETT, a rigid stylet shaped with the same angle as the blade, the GlideRite stylet (GRs), has been made up. Recently, the most suitable characteristics of the introducer have been largely debated: gum elastic bougie, rigid stylet, malleable stylet, and several experiences have been published with different endotracheal introducer utilized in combination with VLS to facilitate intubation maneuver [10–14]. We report our clinical experience in 4 patients, three characterized by potential and one by unexpected difficult intubation, in whom videolaryngo-GlideScope (VLGS) combined with Frova bougie has been used to facilitate endotracheal intubation. 2. Case??1 A 61-year-old woman (BMI: 22.6?kg/m2) was urgently admitted to the anesthesiological evaluation before undergoing the intervention of spinal decompression of cervical C3–C6
Spatial and Temporal Dynamics of Hepatitis B Virus D Genotype in Europe and the Mediterranean Basin
Gianguglielmo Zehender, Erika Ebranati, Elena Gabanelli, Renata Shkjezi, Alessia Lai, Chiara Sorrentino, Alessandra Lo Presti, Mimoza Basho, Raffaele Bruno, Elisabetta Tanzi, Silvia Bino, Massimo Ciccozzi, Massimo Galli
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0037198
Abstract: Hepatitis B virus genotype D can be found in many parts of the world and is the most prevalent strain in south-eastern Europe, the Mediterranean Basin, the Middle East, and the Indian sub-continent. The epidemiological history of the D genotype and its subgenotypes is still obscure because of the scarcity of appropriate studies. We retrieved from public databases a total of 312 gene P sequences of HBV genotype D isolated in various countries throughout the world, and reconstructed the spatio-temporal evolutionary dynamics of the HBV-D epidemic using a Bayesian framework. The phylogeographical analysis showed that India had the highest posterior probability of being the location of the tree root, whereas central Asia was the most probable location of the common ancestor of subgenotypes D1–D3. HBV-D5 (identified in native Indian populations) diverged from the tree root earlier than D1–D3. The time of the most recent common ancestor (tMRCA) of the tree root was 128 years ago, which suggests that the common ancestor of the currently circulating subgenotypes existed in the second half of the XIX century. The mean tMRCA of subgenotypes D1–D3 was between the 1940s and the 1950–60s. On the basis of our phylogeographic reconstruction, it seems that HBV-D reached the Mediterranean area in the middle of the XX century by means of at least two routes: the first pathway (mainly due to the spread of subgenotype D1) crossing the Middle East and reaching north Africa and the eastern Mediterranean, and the second pathway (closely associated with D2) that crossed the former Soviet Union and reached eastern Europe and the Mediterranean through Albania. We hypothesise that the main route of dispersion of genotype D was the unsafe use of injections and drug addiction.
Bayesian Phylogeography of Crimean-Congo Hemorrhagic Fever Virus in Europe
Gianguglielmo Zehender, Erika Ebranati, Renata Shkjezi, Anna Papa, Camilla Luzzago, Elena Gabanelli, Alessandra Lo Presti, Alessia Lai, Giovanni Rezza, Massimo Galli, Silvia Bino, Massimo Ciccozzi
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0079663
Abstract: Crimean-Congo hemorrhagic fever (CCHF) is a zoonosis mainly transmitted by ticks that causes severe hemorrhagic fever and has a mortality rate of 5-60%. The first outbreak of CCHF occurred in the Crimean peninsula in 1944-45 and it has recently emerged in the Balkans and eastern Mediterranean. In order to reconstruct the origin and pathway of the worldwide dispersion of the virus at global and regional (eastern European) level, we investigated the phylogeography of the infection by analysing 121 publicly available CCHFV S gene sequences including two recently characterised Albanian isolates. The spatial and temporal phylogeny was reconstructed using a Bayesian Markov chain Monte Carlo approach, which estimated a mean evolutionary rate of 2.96 x 10-4 (95%HPD=1.6 and 4.7 x 10-4) substitutions/site/year for the analysed fragment. All of the isolates segregated into seven highly significant clades that correspond to the known geographical clades: in particular the two new isolates from northern Albania clustered significantly within the Europe 1 clade. Our phylogeographical reconstruction suggests that the global CCHFV clades originated about one thousand years ago from a common ancestor probably located in Africa. The virus then spread to Asia in the XV century and entered Europe on at least two occasions: the first in the early 1800s, when a still circulating but less or non-pathogenic virus emerged in Greece and Turkey, and the second in the early 1900s, when a pathogenic CCHFV strain began to spread in eastern Europe. The most probable location for the origin of this European clade 1 was Russia, but Turkey played a central role in spreading the virus throughout Europe. Given the close proximity of the infected areas, our data suggest that the movement of wild and domestic ungulates from endemic areas was probably the main cause of the dissemination of the virus in eastern Europe.
Molecular Characterization of HIV-1 Subtype C gp-120 Regions Potentially Involved in Virus Adaptive Mechanisms
Alessandra Cenci, Giuseppe D'Avenio, Lara Tavoschi, Michele Chiappi, Simone Becattini, Maria del Pilar Narino, Orietta Picconi, Daniela Bernasconi, Emanuele Fanales-Belasio, Eftyhia Vardas, Hosea Sukati, Alessandra Lo Presti, Massimo Ciccozzi, Paolo Monini, Barbara Ensoli, Mauro Grigioni, Stefano Buttò
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0095183
Abstract: The role of variable regions of HIV-1 gp120 in immune escape of HIV has been investigated. However, there is scant information on how conserved gp120 regions contribute to virus escaping. Here we have studied how molecular sequence characteristics of conserved C3, C4 and V3 regions of clade C HIV-1 gp120 that are involved in HIV entry and are target of the immune response, are modulated during the disease course. We found an increase of “shifting” putative N-glycosylation sites (PNGSs) in the α2 helix (in C3) and in C4 and an increase of sites under positive selection pressure in the α2 helix during the chronic stage of disease. These sites are close to CD4 and to co-receptor binding sites. We also found a negative correlation between electric charges of C3 and V4 during the late stage of disease counteracted by a positive correlation of electric charges of α2 helix and V5 during the same stage. These data allow us to hypothesize possible mechanisms of virus escape involving constant and variable regions of gp120. In particular, new mutations, including new PNGSs occurring near the CD4 and CCR5 binding sites could potentially affect receptor binding affinity and shield the virus from the immune response.
Pain after earthquake
Chiara Angeletti, Cristiana Guetti, Roberta Papola, Emiliano Petrucci, Maria Laura Ursini, Alessandra Ciccozzi, Francesca Masi, Maria Rosaria Russo, Salvatore Squarcione, Antonella Paladini, Joseph Pergolizzi, Robert Taylor, Giustino Varrassi, Franco Marinangeli
Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine , 2012, DOI: 10.1186/1757-7241-20-43
Abstract: This observational retrospective study evaluated the prevalence and drug treatment of pain in the five weeks following the L'Aquila earthquake (April 6, 2009).958 triage documents were analysed for patients pain severity, pain type, and treatment efficacy.A third of pain patients reported pain with a prevalence of 34.6%. More than half of pain patients reported severe pain (58.8%). Analgesic agents were limited to available drugs: anti-inflammatory agents, paracetamol, and weak opioids. Reduction in verbal numerical pain scores within the first 24 hours after treatment was achieved with the medications at hand. Pain prevalence and characterization exhibited a biphasic pattern with acute pain syndromes owing to trauma occurring in the first 15 days after the earthquake; traumatic pain then decreased and re-surged at around week five, owing to rebuilding efforts. In the second through fourth week, reports of pain occurred mainly owing to relapses of chronic conditions.This study indicates that pain is prevalent during natural disasters, may exhibit a discernible pattern over the weeks following the event, and current drug treatments in this region may be adequate for emergency situations.
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