41 results on '"Alberto Rizzo"'
Search Results
2. Evaluation of analytical performance of the STANDARDTM M10 MPX/OPX assay for the simultaneous DNA detection and clade attribution of Monkeypox virus
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Alessandro Mancon, Angelo Roberto Raccagni, Gloria Gagliardi, Davide Moschese, Alberto Rizzo, Andrea Giacomelli, Miriam Cutrera, Federica Salari, Fiorenza Bracchitta, Spinello Antinori, Andrea Gori, Giuliano Rizzardini, Antonella Castagna, Maria Rita Gismondo, Silvia Nozza, and Davide Mileto
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Monkeypox virus ,clade determination ,methods comparison ,all-in-one RealTime-PCR ,Orthopoxvirus ,Infectious and parasitic diseases ,RC109-216 ,Microbiology ,QR1-502 - Abstract
ABSTRACTMonkeypox virus (MPXV) infection confirmation needs reliable polymerase chain reaction (PCR) assays; in addition, viral clade attribution is a key factor in containment measures, considering a more severe syndrome in clade I and the possibility of simultaneous circulation. This study evaluates the performance of all-in-one STANDARD M10 MPX/OPX (SD BIOSENSOR, South Korea – M10). Frozen samples from 205 subjects were selected and stratified according to routine test results (RealStar® Orthopoxvirus PCR Kit 1.0, Altona DIAGNOTICS, Germany – RS; RS-1): in detail, 100 negative skin lesions (SL) and 200 positive samples at the variable stage of infection were analysed. Positive samples were retested with RS (RS-2). Positive and Negative Percent Agreements (PPA, NPA) were calculated. The median (IQR) Ct values of RS and M10 (OPXV target) assays were highly similar. The PPA of M10 compared to RS-1 was 89.5% considering system interpretation, and 96.0% when the operator classified results as positive if any target was detected; NPA was 100%. Comparing the RS-2 run and M10, an overall concordance of 95.3% between assays was found; however, considering operator interpretation, M10 returned more positive results than RS-2. The occurrence of False-Negative results was likely associated with the influence of thawing on low viral concentration; no False-Positive tests were observed. All samples collected at the time of Mpox diagnosis were positive and M10 correctly attributed the clade (West-Africa/II). The M10 MPX/OPX assay demonstrated high reliability in confirming MPXV infection and clade attribution.
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- 2024
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3. Dynamics of viral DNA shedding and culture viral DNA positivity in different clinical samples collected during the 2022 mpox outbreak in Lombardy, Italy
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Antonio Piralla, Davide Mileto, Alberto Rizzo, Guglielmo Ferrari, Federica Giardina, Stefano Gaiarsa, Greta Petazzoni, Micol Bianchi, Federica Salari, Fiorenza Bracchitta, Josè Camilla Sammartino, Alessandro Ferrari, Gloria Gagliardi, Alessandro Mancon, Claudio Fenizia, Mara Biasin, Francesca Rovida, Stefania Paolucci, Elena Percivalle, Alessandra Lombardi, Valeria Micheli, Silvia Nozza, Antonella Castagna, Davide Moschese, Spinello Antinori, Andrea Gori, Paolo Bonfanti, Roberto Rossotti, Antonella D'Arminio Monforte, Federica Attanasi, Marcello Tirani, Danilo Cereda, Fausto Baldanti, Maria Rita Gismondo, Miriam Cutrera, Marianna Cuomo, Federica De Poli, Giulia Campanini, Antonino Maria Guglielmo Pitrolo, Elizabeth Iskandar, Irene Cassaniti, Raffaele Bruno, Giuliano Rizzardini, Massimo Puoti, Francesco Castelli, Laura Corsico, Andrea Giacomelli, Giacomo Pozza, Giacomo Casalini, Angelo Raccagni, Bendetta Trentacapilli, Costanza Bertoni, Elena Bruzzesi, Caterina Candela, Daniele Tesoro, Giovanni Mule, Alessandra Bandera, Antonio Muscatello Bianca Mariani, Manuel Maffeo, Riccardo Vecchio, and Sara Piccinelli
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Mpox virus ,Molecular epidemiology ,Next generation sequencing ,Re-Emerging virus ,Multiple samples ,Arctic medicine. Tropical medicine ,RC955-962 ,Infectious and parasitic diseases ,RC109-216 - Abstract
Background: Mpox virus (MPXV) has recently spread outside of sub-Saharan Africa. This large multicentre study was conducted in Lombardy, the most densely populated Italian region accounting for more than 40% of Italian cases. The present study aims to: i) evaluate the presence and the shedding duration of MPXV DNA in different body compartments correlating the MPXV viability with the time to onset of symptoms; ii) provide evidence of MPXV persistence in different body compartment as a source of infection and iii) characterize the MPXV evolution by whole genome sequencing (WGS) during the outbreak occurred in Italy. Material and methods: The study included 353 patients with a laboratory-confirmed diagnosis of MPXV infection screened in several clinical specimens in the period May 24th - September 1st, 2022. Viral isolation was attempted from different biological matrices and complete genome sequencing was performed for 61 MPXV strains. Results: MPXV DNA detection was more frequent in the skin (94.4%) with the longest median time of viral clearance (16 days). The actively-replicating virus in cell culture was obtained for 123/377 (32.6%) samples with a significant higher viral quantity on isolation positive samples (20 vs 31, p
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- 2024
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4. Evaluation of 16S-Based Metagenomic NGS as Diagnostic Tool in Different Types of Culture-Negative Infections
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Sara Giordana Rimoldi, Alessandro Tamoni, Alberto Rizzo, Concetta Longobardi, Cristina Pagani, Federica Salari, Caterina Matinato, Chiara Vismara, Gloria Gagliardi, Miriam Cutrera, and Maria Rita Gismondo
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metagenomics ,NGS ,diagnostics ,infection ,bacteria ,culture-negative sample ,Medicine - Abstract
Bacterial infections pose significant global health challenges, often underestimated due to difficulties in accurate diagnosis, especially when culture-based diagnostics fail. This study assesses the effectiveness of 16S-based metagenomic next generation sequencing (NGS) for identifying pathogens in culture-negative clinical samples across various medical settings. Overall, 48% of samples were collected from orthopedics, 15% from neurosurgery, and 12% in cardiac surgery, among others. The detection rate of monomicrobial infections was 68.6%, and 5.7% for polymicrobial infections. In addition, NGS detected bacteria in all samples from the lungs, head and neck, and eye specimens. Cutibacterium acnes (11%, 12/105) was the most frequent microorganism, followed by Staphylococcus epidermidis (10.4%, 11/105), and Staphylococcus aureus (9.5%, 10/105). In conclusion, 16S-targeted metagenomic sequencing enhances pathogen detection capabilities, particularly in instances where traditional cultures fail. By the combination of NGS and bacterial cultures, microbiologists might provide a more accurate diagnosis, guiding more effective treatments and potentially reducing healthcare costs associated with empirical treatments.
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- 2024
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5. Multiple episodes of Plasmodium malariae despite antimalarial treatment: 'Quartana te teneat'?
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Alberto Rizzo, Silvia Grosso, Ivano Faggion, Anna Gigantiello, Federica Salari, Fosca Niero, Simone Passerini, Chiara Mariani, Spinello Antinori, and Maria Rita Gismondo
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Plasmodium malariae ,Malaria ,Recrudescence ,Chloroquine ,Dihydroartemisinin-piperaquine ,Arctic medicine. Tropical medicine ,RC955-962 ,Infectious and parasitic diseases ,RC109-216 - Published
- 2023
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6. Traditional Cultures versus Next Generation Sequencing for Suspected Orthopedic Infection: Experience Gained from a Reference Centre
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Sara Giordana Rimoldi, Davide Brioschi, Daniele Curreli, Federica Salari, Cristina Pagani, Alessandro Tamoni, Concetta Longobardi, Raffaella Bosari, Alberto Rizzo, Simona Landonio, Massimo Coen, Matteo Passerini, Maria Rita Gismondo, Andrea Gori, and Alfonso Manzotti
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prosthetic joint infection ,next-generation sequencing ,bone infections ,Therapeutics. Pharmacology ,RM1-950 - Abstract
(Background) The diagnosis and the antimicrobial treatment of orthopedic infection are challenging, especially in cases with culture-negative results. New molecular methods, such as next-generation sequencing (NGS), promise to overcome some limitations of the standard culture, such as the detection of difficult-to-grow bacteria. However, data are scarce regarding the impact of molecular techniques in real-life scenarios. (Methods) We included cases of suspected orthopedic infection treated with surgery from May 2021 to September 2023. We combined traditional cultures with NGS. For NGS, we performed a metagenomic analysis of ribosomal 16s, and we queried dedicated taxonomic libraries to identify the species. To avoid false positive results, we set a cut-off of 1000 counts of the percentage of frequency of reads. (Results) We included 49 patients in our study. Our results show the presence of bacteria in 36/49 (73%) and 29/49 (59%) cases studied with NGS and traditional cultures, respectively. The concordance rate was 61%. Among the 19/49 discordant cases, in 11/19 cases, cultures were negative and NGS positive; in 4/19, cultures were positive and NGS negative; and in the remaining 4/19, different species were detected by traditional cultures and NGS. (Conclusions) Difficult-to-grow microorganisms, such as slow-growing anaerobic bacteria, were better detected by NGS compared to traditional culture in our study. However, more data to distinguish between true pathogens and contaminants are needed. NGS can be an additional tool to be used for the diagnosis of orthopedic infections and the choice of appropriate antimicrobial therapy.
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- 2023
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7. SARS-CoV-2 viremia and COVID-19 mortality: A prospective observational study.
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Andrea Giacomelli, Elena Righini, Valeria Micheli, Pietro Pinoli, Anna Bernasconi, Alberto Rizzo, Letizia Oreni, Anna Lisa Ridolfo, Spinello Antinori, Stefano Ceri, and Giuliano Rizzardini
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Medicine ,Science - Abstract
BackgroundSARS-CoV-2 viremia has been found to be a potential prognostic factor in patients hospitalized for COVID-19.ObjectiveWe aimed to assess the association between SARS-CoV-2 viremia and mortality in COVID-19 hospitalized patients during different epidemic periods.MethodsA prospective COVID-19 registry was queried to extract all COVID-19 patients with an available SARS-CoV-2 viremia performed at hospital admission between March 2020 and January 2022. SARS-CoV-2 viremia was assessed by means of GeneFinderTM COVID-19 Plus RealAmp Kit assay and SARS-CoV-2 ELITe MGB® Kit using ResultsFour hundred and forty-five out of 2,822 COVID-19 patients had an available SARS-CoV-2 viremia, prevalently males (64.9%) with a median age of 65 years (IQR 55-75). Patients with a positive SARS-CoV-2 viremia (86/445; 19.3%) more frequently presented with a severe or critical disease (67.4% vs 57.1%) when compared to those with a negative SARS-CoV-2 viremia. Deceased subjects (88/445; 19.8%) were older [75 (IQR 68-82) vs 63 (IQR 54-72)] and showed more frequently a detectable SARS-CoV-2 viremia at admission (60.2% vs 22.7%) when compared to survivors. In univariable analysis a positive SARS-CoV-2 viremia was associated with a higher odd of death [OR 5.16 (95% CI 3.15-8.45)] which was confirmed in the multivariable analysis adjusted for age, biological sex and, disease severity [AOR 6.48 (95% CI 4.05-10.45)]. The association between positive SARS-CoV-2 viremia and death was consistent in the period 1 February 2021-31 January 2022 [AOR 5.86 (95% CI 3.43-10.16)] and in subgroup analysis according to disease severity: mild/moderate [AOR 6.45 (95% CI 2.84-15.17)] and severe/critical COVID-19 patients [AOR 6.98 (95% CI 3.68-13.66)].ConclusionsSARS-CoV-2 viremia resulted associated to COVID-19 mortality and should be considered in the initial assessment of COVID-19 hospitalized patients.
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- 2023
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8. Human Monkeypox Experience in a Tertiary Level Hospital in Milan, Italy, between May and October 2022: Epidemiological Features and Clinical Characteristics
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Caterina Candela, Angelo Roberto Raccagni, Elena Bruzzesi, Costanza Bertoni, Alberto Rizzo, Gloria Gagliardi, Diana Canetti, Nicola Gianotti, Davide Mileto, Maria Rita Gismondo, Antonella Castagna, and Silvia Nozza
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Monkeypox virus ,mpox infection ,men who have sex with men ,sexually transmitted infections ,global outbreak ,Microbiology ,QR1-502 - Abstract
Background: Monkeypox virus (mpxv) started to spread to Europe and North America at the beginning of the current outbreak in May 2022, and the World Health Organization (WHO) declared Human Monkeypox (mpox) as a public health emergency of international concern (PHEIC) in July 2022. The aim of this observational analysis is to describe demographical data, symptoms presentation and clinical course till outcome of individuals diagnosed with mpox, between May and October 2022, at our open-access Sexual Health Clinic in IRCCS San Raffaele Hospital in Milan, Italy. Methods: Among people who accessed our Sexual Health Clinic, we considered, as suspected diagnosis of mpox, individuals with consistent symptoms and epidemiological criteria. Following the physical examination, oropharyngeal, anal, genital and cutaneous swabs, plus plasma, urine and seminal fluid were collected as biological materials to detect mpxv DNA. We also performed a screening for sexually transmitted infections (STIs). Results: Overall, 140 individuals with mpox were included in this study. Median age was 37 (interquartile, IQR 33, 43) years old. Males were 137 (98%) and men who have sex with men (MSM) were 134 (96%). As risk factors, we detected travels abroad in 35 (25%) individuals and close contact with mpox cases in 49 (35%). There were 66 (47%) people living with HIV (PLWH). Most frequent symptoms were fever (59%), lymphadenopathy (57%), cutaneous (77%), genital (42%), anal (34%) and oral (26%) lesions, proctitis (39%), sore throat (22%) and generalized rash (5%). At mpox diagnosis, we also observed N. gonorrhoeae in 18 (13%) cases, syphilis in 14 (10%) and C. trachomatis in 12 (9%). Two (1%) people received a concomitant diagnosis of HIV infection. We attended to 21 (15%) complications, with nine (6%) cases of hospitalization including six (IQR 3,7) median hospital days. Forty-five (32%) patients were treated with non-steroidal anti-inflammatory drugs (NSAIDs), 37 (26%) with antibiotics and eight (6%) with antiviral drugs. Conclusions: Similarly to other international cohorts, sexual transmission was most frequently present, and concomitant STIs were common. Symptoms were heterogenous, self-resolving and responsive to therapy. Hospitalization was necessary in few patients. There is uncertainty about the future development of mpox and further studies (e.g., potential disease reservoirs, other possible means of transmission, predictors of severe disease) are still needed.
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- 2023
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9. Independent glial subtypes delay development and extend healthy lifespan upon reduced insulin-PI3K signalling
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Nathaniel S. Woodling, Arjunan Rajasingam, Lucy J. Minkley, Alberto Rizzo, and Linda Partridge
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Ageing ,Astrocytes ,Glia ,Insulin signalling ,Lifespan ,Biology (General) ,QH301-705.5 - Abstract
Abstract Background The increasing age of global populations highlights the urgent need to understand the biological underpinnings of ageing. To this end, inhibition of the insulin/insulin-like signalling (IIS) pathway can extend healthy lifespan in diverse animal species, but with trade-offs including delayed development. It is possible that distinct cell types underlie effects on development and ageing; cell-type-specific strategies could therefore potentially avoid negative trade-offs when targeting diseases of ageing, including prevalent neurodegenerative diseases. The highly conserved diversity of neuronal and non-neuronal (glial) cell types in the Drosophila nervous system makes it an attractive system to address this possibility. We have thus investigated whether IIS in distinct glial cell populations differentially modulates development and lifespan in Drosophila. Results We report here that glia-specific IIS inhibition, using several genetic means, delays development while extending healthy lifespan. The effects on lifespan can be recapitulated by adult-onset IIS inhibition, whereas developmental IIS inhibition is dispensable for modulation of lifespan. Notably, the effects we observe on both lifespan and development act through the PI3K branch of the IIS pathway and are dependent on the transcription factor FOXO. Finally, IIS inhibition in several glial subtypes can delay development without extending lifespan, whereas the same manipulations in astrocyte-like glia alone are sufficient to extend lifespan without altering developmental timing. Conclusions These findings reveal a role for distinct glial subpopulations in the organism-wide modulation of development and lifespan, with IIS in astrocyte-like glia contributing to lifespan modulation but not to developmental timing. Our results enable a more complete picture of the cell-type-specific effects of the IIS network, a pathway whose evolutionary conservation in humans make it tractable for therapeutic interventions. Our findings therefore underscore the necessity for cell-type-specific strategies to optimise interventions for the diseases of ageing.
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- 2020
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10. A case of extremely prolonged viral shedding: Could cell cultures be a diagnostic tool to drive COVID-19 patient discharge?
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Davide Mileto, Antonella Foschi, Alessandro Mancon, Stefania Merli, Federica Staurenghi, Laura Pezzati, Alberto Rizzo, Federico Conti, Francesca Romeri, Dario Bernacchia, Rachele Meroni, Giuliano Rizzardini, Maria Rita Gismondo, and Valeria Micheli
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SARS-CoV-2 ,COVID-19 ,RT-PCR ,Serology ,Viral culture ,Infectious and parasitic diseases ,RC109-216 - Abstract
This study addressed the case of a patient with prolonged COVID-19 viral shedding, reported by Real-Time PCR, until 71 days from symptom onset. However, viral culture received negative results after 30 days from symptom onset. Therefore, viral culture may be a worthwhile test for patients requiring discharge, in particular for those presenting prolonged viral shedding.
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- 2021
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11. A Lab‐On‐chip Tool for Rapid, Quantitative, and Stage‐selective Diagnosis of Malaria
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Marco Giacometti, Francesca Milesi, Pietro Lorenzo Coppadoro, Alberto Rizzo, Federico Fagiani, Christian Rinaldi, Matteo Cantoni, Daniela Petti, Edoardo Albisetti, Marco Sampietro, Mariagrazia Ciardo, Giulia Siciliano, Pietro Alano, Brigitte Lemen, Joel Bombe, Marie Thérèse Nwaha Toukam, Paul Fernand Tina, Maria Rita Gismondo, Mario Corbellino, Romualdo Grande, Gianfranco Beniamino Fiore, Giorgio Ferrari, Spinello Antinori, and Riccardo Bertacco
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diagnostic tests ,hemozoin nanocrystals ,impedimetric detection ,lab‐on‐chip ,magnetic sorting ,malaria ,Science - Abstract
Abstract Malaria remains the most important mosquito‐borne infectious disease worldwide, with 229 million new cases and 409.000 deaths in 2019. The infection is caused by a protozoan parasite which attacks red blood cells by feeding on hemoglobin and transforming it into hemozoin. Despite the WHO recommendation of prompt malaria diagnosis, the quality of microscopy‐based diagnosis is frequently inadequate while rapid diagnostic tests based on antigens are not quantitative and still affected by non‐negligible false negative/positive results. PCR‐based methods are highly performant but still not widely used in endemic areas. Here, a diagnostic tool (TMek), based on the paramagnetic properties of hemozoin nanocrystals in infected red blood cells (i‐RBCs), is reported on. Exploiting the competition between gravity and magnetic forces, i‐RBCs in a whole blood specimen are sorted and electrically detected in a microchip. The amplitude and time evolution of the electrical signal allow for the quantification of i‐RBCs (in the range 10–105 i‐RBC µL−1) and the distinction of the infection stage. A preliminary validation study on 75 patients with clinical suspect of malaria shows on‐field operability, without false negative and a few false positive results. These findings indicate the potential of TMek as a quantitative, stage‐selective, rapid test for malaria.
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- 2021
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12. What was behind the first recognition and characterization of autochthonous SARS‐CoV‐2 transmission in Italy: The impact on European scenario
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Valeria Micheli, Alessandro Mancon, Annalisa Malara, Davide Mileto, Pier Giorgio Villani, Alberto Rizzo, Cristina Pagani, Omar Alquati, and Maria Rita Gismondo
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pandemic ,RT‐PCR ,SARS‐CoV‐2 ,serology ,viral culture ,Medicine ,Medicine (General) ,R5-920 - Abstract
Abstract An Italian male with no link to China Severe Acute Respiratory Syndrome Coronavirus 2 (SARS‐CoV‐2) epidemic presented at Emergency Room (ER) with severe respiratory impairment. The RT‐PCR on 20 February 2020, nasopharyngeal swab revealed SARS‐CoV‐2 infection, confirmed with viral culture and sequencing. This was the first identified autochthonous SARS‐CoV‐2 transmission in Italy, that unveiled global pathogen diffusion. This clinical case highlights an underestimation of SARS‐CoV‐2 circulation, making initial containment measures unfit to face the real situation and delaying the management of potentially affected SARS‐CoV‐2 patients.
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- 2021
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13. Elucidating the 3D Structure of a Surface Membrane Antigen from Trypanosoma cruzi as a Serodiagnostic Biomarker of Chagas Disease
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Flavio Di Pisa, Stefano De Benedetti, Enrico Mario Alessandro Fassi, Mauro Bombaci, Renata Grifantini, Angelo Musicò, Roberto Frigerio, Angela Pontillo, Cinzia Rigo, Sandra Abelli, Romualdo Grande, Nadia Zanchetta, Davide Mileto, Alessandro Mancon, Alberto Rizzo, Alessandro Gori, Marina Cretich, Giorgio Colombo, Martino Bolognesi, and Louise Jane Gourlay
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Chagas disease ,Trypanosoma cruzi ,neglected tropical disease ,structural vaccinology ,peptide microarray ,in silico epitope mapping ,Medicine - Abstract
Chagas disease (CD) is a vector-borne parasitosis, caused by the protozoan parasite Trypanosoma cruzi, that affects millions of people worldwide. Although endemic in South America, CD is emerging throughout the world due to climate change and increased immigratory flux of infected people to non-endemic regions. Containing of the diffusion of CD is challenged by the asymptomatic nature of the disease in early infection stages and by the lack of a rapid and effective diagnostic test. With the aim of designing new serodiagnostic molecules to be implemented in a microarray-based diagnostic set-up for early screening of CD, herein, we report the recombinant production of the extracellular domain of a surface membrane antigen from T. cruzi (TcSMP) and confirm its ability to detect plasma antibodies from infected patients. Moreover, we describe its high-resolution (1.62 Å) crystal structure, to which in silico epitope predictions were applied in order to locate the most immunoreactive regions of TcSMP in order to guide the design of epitopes that may be used as an alternative to the full-length antigen for CD diagnosis. Two putative, linear epitopes, belonging to the same immunogenic region, were synthesized as free peptides, and their immunological properties were tested in vitro. Although both peptides were shown to adopt a structural conformation that allowed their recognition by polyclonal antibodies raised against the recombinant protein, they were not serodiagnostic for T. cruzi infections. Nevertheless, they represent good starting points for further iterative structure-based (re)design cycles.
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- 2022
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14. Human-to-Cat SARS-CoV-2 Transmission: Case Report and Full-Genome Sequencing from an Infected Pet and Its Owner in Northern Italy
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Gabriele Pagani, Alessia Lai, Annalisa Bergna, Alberto Rizzo, Angelica Stranieri, Alessia Giordano, Saverio Paltrinieri, Davide Lelli, Nicola Decaro, Stefano Rusconi, Maria Rita Gismondo, Spinello Antinori, Stefania Lauzi, Massimo Galli, and Gianguglielmo Zehender
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SARS-CoV-2 ,cat ,full-genome analysis ,one health ,Medicine - Abstract
There have been previous reports of the human-to-cat transmission of SARS-CoV-2, but there are only a few molecular studies that have compared the whole genome of the virus in cats and their owners. We here describe a case of domestic SARS-CoV-2 transmission from a healthcare worker to his cat for which nasopharyngeal swabs of both the cat and its owner were used for full-genome analysis. The results indicate that quarantine measures should be extended to pets living in SARS-CoV-2-infected households.
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- 2021
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15. HIV viral load monitoring during monkeypox virus infection among people with HIV
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Angelo Roberto Raccagni, Davide Mileto, Laura Galli, Elena Bruzzesi, Diana Canetti, Alberto Rizzo, Costanza Bertoni, Tommaso Clemente, Francesca Alberton, Antonella Castagna, and Silvia Nozza
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Infectious Diseases ,Immunology ,Immunology and Allergy - Published
- 2023
16. Monkeypox infection among men who have sex with men: PCR testing on seminal fluids
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Angelo Roberto Raccagni, Caterina Candela, Davide Mileto, Diana Canetti, Elena Bruzzesi, Alberto Rizzo, Antonella Castagna, and Silvia Nozza
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Microbiology (medical) ,Infectious Diseases - Published
- 2022
17. Monkeypox and pan-resistant Campylobacter spp infection in Entamoeba histolytica and Chlamydia trachomatis re-infection in a man who have sex with men
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Angelo Roberto Raccagni, Davide Mileto, Diana Canetti, Andrea Marco Tamburini, Alberto Rizzo, Elena Bruzzesi, Antonella Castagna, and Silvia Nozza
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Male ,Microbiology (medical) ,Infectious Diseases ,Reinfection ,Entamoeba histolytica ,Sexually Transmitted Diseases ,Animals ,Humans ,Campylobacter ,Chlamydia trachomatis ,Monkeypox ,Chlamydia Infections - Published
- 2022
18. Late positivization of oropharyngeal, plasma, anal, Semen and urine specimens which tested negative at time of mpox diagnosis
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Angelo Roberto Raccagni, Davide Mileto, Alberto Rizzo, Maria Rita Gismondo, Antonella Castagna, and Silvia Nozza
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Microbiology (medical) ,Infectious Diseases ,General Medicine - Published
- 2023
19. Natural history of human Monkeypox in individuals attending a sexual health clinic in Milan, Italy
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Davide Moschese, Giacomo Pozza, Andrea Giacomelli, Davide Mileto, Maria Vittoria Cossu, Martina Beltrami, Alberto Rizzo, Maria Rita Gismondo, Giuliano Rizzardini, and Spinello Antinori
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Microbiology (medical) ,Infectious Diseases - Published
- 2023
20. Viral bloodstream detection in mpox patients: An observational multicentric study
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Alberto Rizzo, Davide Moschese, Benedetta Trentacapilli, Maria Vittoria Cossu, Andrea Giacomelli, Federica Salari, Micol Bianchi, Angelo Roberto Raccagni, Valeria Micheli, Andrea Gori, Emanuela Messina, Spinello Antinori, Maria Rita Gismondo, Antonella Castagna, Davide Mileto, Giuliano Rizzardini, Alessandra Lombardi, and Silvia Nozza
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Microbiology (medical) ,Infectious Diseases - Published
- 2023
21. Beyond stigma: Monkeypox infection in a 27-year-old woman
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Costanza Bertoni, Angelo Roberto Raccagni, Caterina Candela, Elena Bruzzesi, Davide Mileto, Diana Canetti, Alberto Rizzo, Giulia Morsica, Antonella Castagna, and Silvia Nozza
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Infectious Diseases ,Virology - Published
- 2022
22. Role of multi-site sampling in the diagnosis of human Monkeypox
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Alberto Rizzo, Davide Mileto, Davide Moschese, Caterina Candela, Alessandro Mancon, Andrea Giacomelli, Angelo Roberto Raccagni, Federica Salari, Maria Vittoria Cossu, Valeria Micheli, Antonella Castagna, Giuliano Rizzardini, Alessandra Lombardi, Silvia Nozza, and Maria Rita Gismondo
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Microbiology (medical) ,Infectious Diseases - Published
- 2022
23. Concomitant diagnosis of sexually transmitted infections and human monkeypox in patients attending a sexual health clinic in Milan, Italy
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Alberto Rizzo, Giacomo Pozza, Federica Salari, Andrea Giacomelli, Davide Mileto, Maria Vittoria Cossu, Alessandro Mancon, Gloria Gagliardi, Bianchi Micol, Valeria Micheli, Amedeo Capetti, Spinello Antinori, Maria Rita Gismondo, Pietro Olivieri, and Alessandra Lombardi
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Infectious Diseases ,Virology - Abstract
In 2022, many monkeypox (MPX) outbreaks have been documented in countries where MPX was not endemic. It spread all around the world, especially in European Union and United States. While MPX is classically considered to be transmitted through close contact with lesions, the hypothesis of sexual transmission has been proposed. This study considered a total of 49 patients suspected for MPX that were also tested for other sexually transmitted infections (STIs), including Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, and Trichomonas vaginalis. The data from coinfected patients suggested that MPXV and STIs might share the same route of inoculum, corroborating the hypothesis of possible sexual transmission for the emerging poxvirus. And like any other STI, MPX should be considered without stigmatization.
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- 2022
24. Persistent detection and sequencing of SARS-CoV-2 in the bloodstream of an immunocompromised patient
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Alberto Rizzo, Antonella Foschi, Fiorenza Bracchitta, Ivano Faggion, Federica Salari, Fabio Borgonovo, Chiara Fusetti, Davide Mileto, Giuliano Rizzardini, Alessandra Lombardi, Maria R. Gismondo, and Valeria Micheli
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Infectious Diseases ,Virology - Published
- 2022
25. Imagine that: creating a 'third space' for young people with high functioning autism through the use of technology in a social setting.
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Alberto Rizzo, Stefan Schutt, and Dale Linegar
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- 2012
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26. Real-life use of cidofovir for the treatment of severe monkeypox cases
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Angelo Roberto Raccagni, Caterina Candela, Elena Bruzzesi, Davide Mileto, Diana Canetti, Alberto Rizzo, Antonella Castagna, and Silvia Nozza
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Infectious Diseases ,Virology - Published
- 2022
27. First Identification of the New Severe Acute Respiratory Syndrome Coronavirus 2 Omicron Variant (B.1.1.529) in Italy
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Valeria Micheli, Fiorenza Bracchitta, Alberto Rizzo, Alessandro Mancon, Davide Mileto, Alessandra Lombardi, Paola Stefanelli, and Maria Rita Gismondo
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Microbiology (medical) ,Infectious Diseases - Abstract
We identified the first case in Italy of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) B.1.1.529 variant, using whole-genome sequencing in an Italian subject traveling from Mozambique. Specific mutation profiles deserve further investigations to clarify potential effects on vaccination efficacy. This case highlights the crucial role of rapid and continuous surveillance of SARS-CoV-2 variant circulation.
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- 2022
28. Independent glial subtypes delay development and extend healthy lifespan upon reduced insulin-PI3K signalling
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Lucy J. Minkley, Arjunan Rajasingam, Linda Partridge, Nathaniel S. Woodling, and Alberto Rizzo
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Nervous system ,Cell type ,Physiology ,Cell ,Longevity ,Plant Science ,Biology ,General Biochemistry, Genetics and Molecular Biology ,Conserved sequence ,03 medical and health sciences ,Phosphatidylinositol 3-Kinases ,0302 clinical medicine ,Structural Biology ,Glia ,medicine ,Animals ,Drosophila Proteins ,Insulin ,Transcription factor ,lcsh:QH301-705.5 ,Ecology, Evolution, Behavior and Systematics ,PI3K/AKT/mTOR pathway ,030304 developmental biology ,0303 health sciences ,Lifespan ,Insulin signalling ,Cell Biology ,Ageing ,medicine.anatomical_structure ,Signalling ,Drosophila melanogaster ,lcsh:Biology (General) ,Astrocytes ,General Agricultural and Biological Sciences ,Neuroscience ,Neuroglia ,030217 neurology & neurosurgery ,Developmental Biology ,Biotechnology ,Signal Transduction ,Research Article - Abstract
Background The increasing age of global populations highlights the urgent need to understand the biological underpinnings of ageing. To this end, inhibition of the insulin/insulin-like signalling (IIS) pathway can extend healthy lifespan in diverse animal species, but with trade-offs including delayed development. It is possible that distinct cell types underlie effects on development and ageing; cell-type-specific strategies could therefore potentially avoid negative trade-offs when targeting diseases of ageing, including prevalent neurodegenerative diseases. The highly conserved diversity of neuronal and non-neuronal (glial) cell types in the Drosophila nervous system makes it an attractive system to address this possibility. We have thus investigated whether IIS in distinct glial cell populations differentially modulates development and lifespan in Drosophila. Results We report here that glia-specific IIS inhibition, using several genetic means, delays development while extending healthy lifespan. The effects on lifespan can be recapitulated by adult-onset IIS inhibition, whereas developmental IIS inhibition is dispensable for modulation of lifespan. Notably, the effects we observe on both lifespan and development act through the PI3K branch of the IIS pathway and are dependent on the transcription factor FOXO. Finally, IIS inhibition in several glial subtypes can delay development without extending lifespan, whereas the same manipulations in astrocyte-like glia alone are sufficient to extend lifespan without altering developmental timing. Conclusions These findings reveal a role for distinct glial subpopulations in the organism-wide modulation of development and lifespan, with IIS in astrocyte-like glia contributing to lifespan modulation but not to developmental timing. Our results enable a more complete picture of the cell-type-specific effects of the IIS network, a pathway whose evolutionary conservation in humans make it tractable for therapeutic interventions. Our findings therefore underscore the necessity for cell-type-specific strategies to optimise interventions for the diseases of ageing.
- Published
- 2020
29. Rapid lateral-flow immunochromatographic tests to assess anti N/S IgG seropositivity after BNT162b2 vaccine: a cross-sectional study
- Author
-
Matteo Siano, Matteo Passerini, Massimo Galli, Letizia Oreni, Laura Milazzo, Gloria Gagliardi, Alberto Rizzo, Federico Conti, Marco Schiuma, Alice Covizzi, Anna Lisa Ridolfo, Cinzia Bassoli, Giuliano Rizzardini, Laura Pezzati, Alessandro Torre, Marco Piscaglia, Andrea Giacomelli, Davide Mileto, and Spinello Antinori
- Subjects
Microbiology (medical) ,2019-20 coronavirus outbreak ,Vaccines ,COVID-19 Vaccines ,Coronavirus disease 2019 (COVID-19) ,Cross-sectional study ,business.industry ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Antibodies, Viral ,Virology ,Article ,Infectious Diseases ,Cross-Sectional Studies ,Immunoglobulin G ,Medicine ,Humans ,business ,BNT162 Vaccine - Published
- 2021
30. Structural Inequality in Refugee Participation in Higher Education
- Author
-
Les Terry, Ryan Naylor, Nathan G. Mifsud, Nga Nguyen, and Alberto Rizzo
- Subjects
050101 languages & linguistics ,Higher education ,business.industry ,Refugee ,05 social sciences ,Geography, Planning and Development ,050301 education ,Political Science and International Relations ,0501 psychology and cognitive sciences ,Demographic economics ,Sociology ,business ,0503 education ,Structural inequality - Abstract
Structural inequality is a framework that examines conditions in which groups of people experience unequal opportunities in terms of roles, rights and decision-making compared to others. This research sought to examine whether students from refugee backgrounds faced structural inequalities in their access to higher education. Data regarding the participation of refugee students in higher education between 2011 and 2014 was obtained from the Australian Department of Education and Training. This data was compared with sector averages and those of students from formal equity backgrounds to establish possible structural impediments to university study. Students from refugee backgrounds were found to face both horizontal and vertical inequalities in their access to higher education, as do other equity groups. The experience of refugee students appears to have unique features, however, including gender, age, type of institution accessed and potentially field of study. These barriers may be addressed to some extent by university outreach and support programmes, but more will be required to facilitate full participation in higher education by these students.
- Published
- 2019
31. Inactivation of SARS-CoV-2 in the Liquid Phase: Are Aqueous Hydrogen Peroxide and Sodium Percarbonate Efficient Decontamination Agents?
- Author
-
Davide Mileto, Federica Staurenghi, Stefano Econdi, Alessandro Mancon, Matteo Guidotti, Maria Rita Gismondo, and Alberto Rizzo
- Subjects
Diminution ,Chemical Health and Safety ,Aqueous solution ,SARS-CoV-2 ,Disinfectant ,viruses ,virucidal solutions ,COVID-19 ,hydrogen peroxide ,General Chemistry ,Sodium percarbonate ,medicine.disease_cause ,chemistry.chemical_compound ,Ingredient ,chemistry ,medicine ,sodium percarbonate ,chemical inactivation ,biocidal agents ,Hydrogen peroxide ,Citric acid ,disinfection ,Coronavirus ,Nuclear chemistry ,Research Article - Abstract
A diluted 3% w/w hydrogen peroxide solution acidified to pH 2 5 by adding citric acid inactivated SARS-CoV-2 virus by more than 4 orders of magnitude in 5 min After a contact time of 15 min, no viral replication was detected Aqueous solutions of sodium percarbonate inactivated coronavirus by >3 log10 diminution in 15 min Conversely, H2O2 solutions with no additives displayed a scarce virucidal activity (1 1 log10 diminution in 5 min), confirming that a pH-modifying ingredient is necessary to have a H2O2-based disinfectant active against the novel coronavirus © 2021 American Chemical Society
- Published
- 2021
32. What was behind the first recognition and characterization of autochthonous SARS-CoV-2 transmission in Italy: who opened Pandora’s Box in Europe?
- Author
-
Piergiorgio Villani, Annalisa Malara, Valeria Micheli, Cristina Pagani, Alberto Rizzo, Maria Rita Gismondo, Omar Alquati, Alessandro Mancon, and Davide Mileto
- Subjects
body regions ,Geography ,Transmission (medicine) ,Viral culture ,viruses ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Respiratory impairment ,fungi ,skin and connective tissue diseases ,Virology ,respiratory tract diseases - Abstract
An Italian male with no link to China SARS-CoV-2 epidemic presented at Emergency Room with severe respiratory impairment. The RT-PCR on 20th February, 2020, nasopharyngeal swab revealed SARS-CoV-2 infection, confirmed with viral culture and sequencing. This was the first identified autochthonous SARS-CoV-2 transmission in Italy, that unveiled global pathogen diffusion.
- Published
- 2021
33. A Lab-On-chip Tool for Rapid, Quantitative, and Stage-selective Diagnosis of Malaria
- Author
-
Giorgio Ferrari, Brigitte Lemen, Giulia Siciliano, Gianfranco Beniamino Fiore, Riccardo Bertacco, Mario Corbellino, Federico Fagiani, Marie Thérèse Nwaha Toukam, Marco Giacometti, Pietro Lorenzo Coppadoro, Spinello Antinori, Christian Rinaldi, Maria Rita Gismondo, Mariagrazia Ciardo, Romualdo Grande, Paul Fernand Tina, Francesca Milesi, Pietro Alano, Alberto Rizzo, Marco Sampietro, Matteo Cantoni, Joel Bombe, Edoardo Albisetti, and Daniela Petti
- Subjects
Validation study ,Erythrocytes ,General Chemical Engineering ,Science ,malaria ,General Physics and Astronomy ,Medicine (miscellaneous) ,Biochemistry, Genetics and Molecular Biology (miscellaneous) ,Sensitivity and Specificity ,diagnostic tests ,hemozoin nanocrystals ,impedimetric detection ,lab-on-chip ,magnetic sorting ,red blood cells ,Lab-On-A-Chip Devices ,parasitic diseases ,medicine ,Humans ,General Materials Science ,Stage (cooking) ,lab‐on‐chip ,Full Paper ,business.industry ,Hemozoin ,General Engineering ,Diagnostic test ,Reproducibility of Results ,medicine.disease ,Protozoan parasite ,Diagnosis of malaria ,Infectious disease (medical specialty) ,Evaluation Studies as Topic ,Immunology ,business ,Malaria - Abstract
Malaria remains the most important mosquito‐borne infectious disease worldwide, with 229 million new cases and 409.000 deaths in 2019. The infection is caused by a protozoan parasite which attacks red blood cells by feeding on hemoglobin and transforming it into hemozoin. Despite the WHO recommendation of prompt malaria diagnosis, the quality of microscopy‐based diagnosis is frequently inadequate while rapid diagnostic tests based on antigens are not quantitative and still affected by non‐negligible false negative/positive results. PCR‐based methods are highly performant but still not widely used in endemic areas. Here, a diagnostic tool (TMek), based on the paramagnetic properties of hemozoin nanocrystals in infected red blood cells (i‐RBCs), is reported on. Exploiting the competition between gravity and magnetic forces, i‐RBCs in a whole blood specimen are sorted and electrically detected in a microchip. The amplitude and time evolution of the electrical signal allow for the quantification of i‐RBCs (in the range 10–105 i‐RBC µL−1) and the distinction of the infection stage. A preliminary validation study on 75 patients with clinical suspect of malaria shows on‐field operability, without false negative and a few false positive results. These findings indicate the potential of TMek as a quantitative, stage‐selective, rapid test for malaria., Malaria is caused by the Plasmodium parasite which feeds on hemoglobin and produces paramagnetic hemozoin crystals within red blood cells (RBCs). A quantitative and stage‐selective pan‐malaria diagnostic test is disclosed, based on a simple concept implemented on a microchip: the sorting and electrical detection of infected RBCs, thanks to the competition between magnetic and gravity forces.
- Published
- 2020
34. Prevalence of Chlamydia trachomatis Infection, Serovar Distribution and Co-Infections with Seven High-Risk HPV Types among Italian Women with a Recent History of Abnormal Cervical Cytology
- Author
-
Alberto Rizzo, Clementina Cocuzza, Marianna Martinelli, Giovanni Sotgiu, Narcisa Muresu, Rosario Musumeci, Fabio Landoni, Andrea Piana, Martinelli, M, Musumeci, R, Rizzo, A, Muresu, N, Piana, A, Sotgiu, G, Landoni, F, and Cocuzza, C
- Subjects
Serotype ,Health, Toxicology and Mutagenesis ,lcsh:Medicine ,Chlamydia trachomatis ,medicine.disease_cause ,Polymerase Chain Reaction ,0302 clinical medicine ,Chlamydia trachomatis serovars ,Epidemiology ,Prevalence ,Mass Screening ,030212 general & internal medicine ,human papillomavirus ,Papillomaviridae ,Human papillomavirus 16 ,medicine.diagnostic_test ,Obstetrics ,Coinfection ,Incidence ,HPV infection ,HPV co-infection ,female genital diseases and pregnancy complications ,Italy ,030220 oncology & carcinogenesis ,Female ,Restriction fragment length polymorphism ,Adult ,medicine.medical_specialty ,Sexually Transmitted Diseases ,Serogroup ,Article ,03 medical and health sciences ,Chlamydia trachomati ,medicine ,Humans ,Pap test ,Typing ,Chlamydia trachomatis serovar ,business.industry ,lcsh:R ,Papillomavirus Infections ,Public Health, Environmental and Occupational Health ,Chlamydia Infections ,medicine.disease ,Uterine Cervical Dysplasia ,Human papillomaviru ,Abnormal cervical cytology ,business - Abstract
Chlamydia trachomatis (Ct) and human papillomavirus (HPV) are the most prevalent sexually transmitted infections throughout the world. Despite the serious complications associated with chronic Ct infections in sexually active women, a screening program is not yet available in Italy. Moreover, HPV/Ct co-infections are also known to occur frequently, increasing the risk of HPV-induced carcinogenesis. The aim of this study was to evaluate the prevalence of Ct infections, the distribution of Ct serovars, and the incidences of Ct/HPV co-infections among women with a recent history of abnormal cervical cytology. Cervical samples were collected from 199 women referred for a gynecological visit following an abnormal Pap test results. All samples were tested for the presence of Ct and HPV DNA using real-time PCR assays, Ct typing of positive samples was performed by PCR&ndash, RFLP (restriction fragment length polymorphism) targeting the ompA gene. A high percentage of these women (12.8% and 21.7% with or without abnormal cytology on &ldquo, retesting&rdquo, respectively) were found to be Ct positive. Serovar F was the most prevalent type in Ct positive women, followed by E and K. Ct/HPV co-infections were detected in 7% (14/199) of enrolled women, with HPV-16, HPV-51, and HPV-52 being most frequently identified in co-infections. This study provides new epidemiological data on the prevalence of Ct and associated HPV infection in women with a recent history of abnormal cervical cytology in Italy, where notification of cases is not mandatory.
- Published
- 2019
35. Consistency relations for large-scale structures: Applications for the integrated Sachs-Wolfe effect and the kinematic Sunyaev-Zeldovich effect
- Author
-
Patrick Valageas, David F. Mota, Luca Alberto Rizzo, Institut de Physique Théorique - UMR CNRS 3681 (IPHT), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institute of Theoretical Astrophysics [Oslo], University of Oslo (UiO), ANR-12-BS05-0002,COSMO@NLO,Les grandes structures de l'univers au delà le l'ordre linéaire(2012), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
- Subjects
large-scale structure of the Universe ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Cosmic microwave background ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Momentum ,Consistency (statistics) ,0103 physical sciences ,Statistical physics ,Limit (mathematics) ,010303 astronomy & astrophysics ,Weak gravitational lensing ,Physics ,[PHYS]Physics [physics] ,010308 nuclear & particles physics ,Spectral density ,Astronomy and Astrophysics ,Sachs–Wolfe effect ,Cosmology ,Space and Planetary Science ,Time derivative ,large-scale structure of Universe ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
Consistency relations of large-scale structures provide exact nonperturbative results for cross-correlations of cosmic fields in the squeezed limit. They only depend on the equivalence principle and the assumption of Gaussian initial conditions, and remain nonzero at equal times for cross-correlations of density fields with velocity or momentum fields, or with the time derivative of density fields. We show how to apply these relations to observational probes that involve the integrated Sachs-Wolfe effect or the kinematic Sunyaev-Zeldovich effect. In the squeezed limit, this allows us to express the three-point cross-correlations, or bispectra, of two galaxy or matter density fields, or weak lensing convergence fields, with the secondary Cosmic Microwave Background (CMB) distortion in terms of products of a linear and a nonlinear power spectrum. In particular, we find that cross-correlations with the integrated Sachs-Wolfe effect show a specific angular dependence. These results could be used to test the equivalence principle and the primordial Gaussianity, or to check the modeling of large-scale structures., 10 pages
- Published
- 2017
36. Ultra-local models of modified gravity without kinetic term
- Author
-
Luca Alberto Rizzo, Philippe Brax, Patrick Valageas, Institut de Physique Théorique - UMR CNRS 3681 (IPHT), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), ANR-12-BS05-0002,COSMO@NLO,Les grandes structures de l'univers au delà le l'ordre linéaire(2012), and European Project: 690575,H2020,H2020-MSCA-RISE-2015,InvisiblesPlus(2016)
- Subjects
Physics ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,010308 nuclear & particles physics ,Degenerate energy levels ,Halo mass function ,Fifth force ,FOS: Physical sciences ,Kinetic term ,General Relativity and Quantum Cosmology (gr-qc) ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,General Relativity and Quantum Cosmology ,Redshift ,Amplitude ,13. Climate action ,Quantum mechanics ,0103 physical sciences ,[PHYS.GRQC]Physics [physics]/General Relativity and Quantum Cosmology [gr-qc] ,Halo ,010306 general physics ,Scalar field ,Astrophysics - Cosmology and Nongalactic Astrophysics ,Mathematical physics - Abstract
We present a class of modified-gravity theories which we call ultra-local models. We add a scalar field, with negligible kinetic terms, to the Einstein-Hilbert action. We also introduce a conformal coupling to matter. This gives rise to a new screening mechanism which is not entirely due to the non-linearity of the scalar field potential or the coupling function but to the absence of the kinetic term. As a result this removes any fifth force between isolated objects in vacuum. The predictions of these models only depend on a single free function, as the potential and the coupling function are degenerate, with an amplitude given by a parameter $\alpha \lesssim 10^{-6}$, whose magnitude springs from requiring a small modification of Newton's potential astrophysically and cosmologically. This singles out a redshift $z_{\alpha} \sim \alpha^{-1/3} \gtrsim 100$ where the fifth force is the greatest. The cosmological background follows the $\Lambda$-CDM history within a $10^{-6}$ accuracy, while cosmological perturbations are significantly enhanced (or damped) on small scales, $k \gtrsim 2 h {\rm Mpc}^{-1}$ at $z=0$. The spherical collapse and the halo mass function are modified in the same manner. We find that the modifications of gravity are greater for galactic or sub-galactic structures. We also present a thermodynamic analysis of the non-linear and inhomogeneous fifth-force regime where we find that the Universe is not made more inhomogeneous before $z_\alpha$ when the fifth force dominates, and does not lead to the existence of clumped matter on extra small scales inside halos for large masses while this possibility exists for masses $M\lesssim 10^{11} M_\odot$ where the phenomenology of ultra-local models would be most different from $\Lambda$-CDM., Comment: 40 pages, 23 figures, updated references
- Published
- 2016
37. Non-zero density-velocity consistency relations for large scale structures
- Author
-
Patrick Valageas, David F. Mota, Luca Alberto Rizzo, Institut de Physique Théorique - UMR CNRS 3681 (IPHT), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), University of Oslo (UiO), and ANR-12-BS05-0002,COSMO@NLO,Les grandes structures de l'univers au delà le l'ordre linéaire(2012)
- Subjects
Physics ,[PHYS]Physics [physics] ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,010308 nuclear & particles physics ,Gaussian ,FOS: Physical sciences ,General Physics and Astronomy ,Kinematics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Galaxy ,Momentum ,Nonlinear system ,symbols.namesake ,Theoretical physics ,Amplitude ,Consistency (statistics) ,0103 physical sciences ,symbols ,Vector field ,Statistical physics ,010303 astronomy & astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present exact kinematic consistency relations for cosmological structures that do not vanish at equal times and can thus be measured in surveys. These rely on cross-correlations between the density and velocity, or momentum, fields. Indeed, the uniform transport of small-scale structures by long wavelength modes, which cannot be detected at equal times by looking at density correlations only, gives rise to a shift in the amplitude of the velocity field that could be measured. These consistency relations only rely on the weak equivalence principle and Gaussian initial conditions. They remain valid in the non-linear regime and for biased galaxy fields. They can be used to constrain non-standard cosmological scenarios or the large-scale galaxy bias., 5 pages
- Published
- 2016
38. Supersymmetric chameleons and ultra-local models
- Author
-
Philippe Brax, Patrick Valageas, Luca Alberto Rizzo, Institut de Physique Théorique - UMR CNRS 3681 (IPHT), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), ANR-12-BS05-0002,COSMO@NLO,Les grandes structures de l'univers au delà le l'ordre linéaire(2012), and European Project: 690575,H2020,H2020-MSCA-RISE-2015,InvisiblesPlus(2016)
- Subjects
Physics ,[PHYS]Physics [physics] ,Particle physics ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,010308 nuclear & particles physics ,Hot dark matter ,High Energy Physics::Phenomenology ,Dark matter ,Scalar field dark matter ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Dark matter halo ,98.80.-k ,0103 physical sciences ,Warm dark matter ,Gravitino ,010306 general physics ,Light dark matter ,Dark fluid ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
Super-chameleon models where all types of matter belong to three secluded sectors, i.e. the dark, supersymmetry breaking and matter sectors, are shown to be dynamically equivalent to ultra-local models of modified gravity. In the dark sector, comprising both dark matter and dark energy, the interaction range between the dark energy field and dark matter is constrained to be extremely short, i.e. shorter than the inverse gravitino mass set by supersymmetry breaking. This realises an extreme version of chameleon screening of the dark energy interaction. On the other hand, the baryonic matter sector decouples from the dark energy in a Damour-Polyakov way. These two mechanisms preclude the existence of any modification of gravity locally in the Solar System due to the presence of the super-chameleon field. On larger scales, the super-chameleon can have effects on the growth of structure and the number of dark matter halos. It can also affect the dynamics of galaxies where the fifth force interaction that it induces can have the same order of magnitude as Newton's interaction., 23 pages, 14 figures. arXiv admin note: text overlap with arXiv:1605.02938
- Published
- 2016
39. Testing Modified Gravity with Cosmic Shear
- Author
-
Peter Coles, Luca Alberto Rizzo, L. van Waerbeke, Patrick Valageas, Joachim Harnois-Déraps, Philippe Brax, Dipak Munshi, Institut de Physique Théorique - UMR CNRS 3681 (IPHT), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Life Sciences, Università di Messina, De Laborderie, Emmanuelle, and Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)
- Subjects
High Energy Physics - Theory ,Particle physics ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Cold dark matter ,media_common.quotation_subject ,Astrophysics::High Energy Astrophysical Phenomena ,Dark matter ,FOS: Physical sciences ,General Relativity and Quantum Cosmology (gr-qc) ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,General Relativity and Quantum Cosmology ,Gravitation ,QC ,Weak gravitational lensing ,QB ,media_common ,Physics ,[PHYS.GRQC] Physics [physics]/General Relativity and Quantum Cosmology [gr-qc] ,[PHYS.HTHE]Physics [physics]/High Energy Physics - Theory [hep-th] ,Astronomy and Astrophysics ,Universe ,Massless particle ,Baryon ,High Energy Physics - Theory (hep-th) ,Space and Planetary Science ,[PHYS.GRQC]Physics [physics]/General Relativity and Quantum Cosmology [gr-qc] ,[PHYS.HTHE] Physics [physics]/High Energy Physics - Theory [hep-th] ,Neutrino ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We use the cosmic shear data from the Canada-France-Hawaii Telescope Lensing Survey to place constraints on $f(R)$ and {\it Generalized Dilaton} models of modified gravity. This is highly complimentary to other probes since the constraints mainly come from the non-linear scales: maximal deviations with respects to the General-Relativity + $\Lambda$CDM scenario occurs at $k\sim1 h \mbox{Mpc}^{-1}$. At these scales, it becomes necessary to account for known degeneracies with baryon feedback and massive neutrinos, hence we place constraints jointly on these three physical effects. To achieve this, we formulate these modified gravity theories within a common tomographic parameterization, we compute their impact on the clustering properties relative to a GR universe, and propagate the observed modifications into the weak lensing $\xi_{\pm}$ quantity. Confronted against the cosmic shear data, we reject the $f(R)$ $\{ |f_{R_0}|=10^{-4}, n=1\}$ model with more than 99.9% confidence interval (CI) when assuming a $\Lambda$CDM dark matter only model. In the presence of baryonic feedback processes and massive neutrinos with total mass up to 0.2eV, the model is disfavoured with at least 94% CI in all different combinations studied. Constraints on the $\{ |f_{R_0}|=10^{-4}, n=2\}$ model are weaker, but nevertheless disfavoured with at least 89% CI. We identify several specific combinations of neutrino mass, baryon feedback and $f(R)$ or Dilaton gravity models that are excluded by the current cosmic shear data. Notably, universes with three massless neutrinos and no baryon feedback are strongly disfavoured in all modified gravity scenarios studied. These results indicate that competitive constraints may be achieved with future cosmic shear data., Comment: 13 pages, 7 figures, 2 tables
- Published
- 2015
40. K-mouflage effects on clusters of galaxies
- Author
-
Luca Alberto Rizzo, Philippe Brax, and Patrick Valageas
- Subjects
Physics ,Nuclear and High Energy Physics ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,010308 nuclear & particles physics ,Halo mass function ,FOS: Physical sciences ,Perfect fluid ,General Relativity and Quantum Cosmology (gr-qc) ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Sunyaev–Zel'dovich effect ,01 natural sciences ,Galaxy ,General Relativity and Quantum Cosmology ,law.invention ,law ,0103 physical sciences ,Cluster (physics) ,Hydrostatic equilibrium ,010303 astronomy & astrophysics ,Scalar field ,Galaxy cluster ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We investigate the effects of a K-mouflage modification of gravity on the dynamics of clusters of galaxies. We extend the description of K-mouflage to situations where the scalar field responsible for the modification of gravity is coupled to a perfect fluid with pressure. We describe the coupled system at both the background cosmology and cosmological perturbations levels, focusing on cases where the pressure emanates from small-scale nonlinear physics. We derive these properties in both the Einstein and Jordan frames, as these two frames already differ by a few percents at the background level for K-mouflage scenarios, and next compute cluster properties in the Jordan frame that is better suited to these observations. Galaxy clusters are not screened by the K-mouflage mechanism and therefore feel the modification of gravity in a maximal way. This implies that the halo mass function deviates from $\Lambda$-CDM by a factor of order one for masses $M\gtrsim 10^{14} \ h^{-1} M_\odot$. We then consider the hydrostatic equilibrium of gases embedded in galaxy clusters and the consequences of K-mouflage on the X-ray cluster luminosity, the gas temperature, and the Sunyaev-Zel'dovich effect. We find that the cluster temperature function, and more generally number counts, are largely affected by K-mouflage, mainly due to the increased cluster abundance in these models. Other scaling relations such as the mass-temperature and the temperature-luminosity relations are only modified at the percent level due to the constraints on K-mouflage from local Solar System tests., Comment: 34 pages
- Published
- 2015
41. Imagine that
- Author
-
Stefan Schutt, Dale Linegar, and Alberto Rizzo
- Subjects
Zone of proximal development ,Learning environment ,Learning community ,media_common.quotation_subject ,Activity theory ,medicine.disease ,Social engagement ,Creativity ,High-functioning autism ,medicine ,Autism ,Psychology ,Cognitive psychology ,media_common - Abstract
In this paper we describe the knowledge building process involved in creating The Lab, a technology-enabled 'learning community' of young people with Asperger's Syndrome (AS) and High-Functioning Autism (HFA), and their parents. We use Vygotsky's (1978) cultural-historical approach to analyse social engagement through material, individual, and social interactions and the emergence of a 'third space' (Gutierrez, 1999 & 2008) as a particular kind of 'zone of proximal development' in developing an effective learning environment. We speculate on the centrality of the sensory and perceptual differences of AS and HFA people as contributing to a better understanding of the role of embodied imagination and creativity as essential aspects of their 'difference' and their distinct patterns of social and cultural relations.
- Published
- 2012
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