27 results on '"Veschetti L"'
Search Results
2. P130 Achromobacter spp. phenotypic differences between chronic and occasional lung infection in cystic fibrosis
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Saitta, G.M., primary, Sandri, A., additional, Veschetti, L., additional, Mantovani, R. Passarelli, additional, Sorio, C., additional, Melotti, P., additional, Fiscarelli, E.V., additional, Signoretto, C., additional, Malerba, G., additional, Boaretti, M., additional, and Lleò, M.M., additional
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- 2022
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3. WS13.04 In vivo lung inflammation induced by Achromobacter spp. clinical isolates with different virulence characteristics
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Sandri, A., primary, Saitta, G.M., additional, Mantovani, R. Passarelli, additional, Boschi, F., additional, Veschetti, L., additional, Melotti, P., additional, Signoretto, C., additional, Boaretti, M., additional, and Lleo, M.M., additional
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- 2022
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4. Towards pocket-sized genomic analyses: cross-platform benchmark of multi-organism genomic data indexing and alignment
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Treccani, M, Veschetti, L, and Malerba, G
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Raspberry Pi ,Raspberry Pi, Alignment, Genomics ,Genomics ,Alignment - Published
- 2022
5. 486: Virulence and antibiotic resistance of Achromobacter spp. isolates from chronic and occasional lung infection in cystic fibrosis patients
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Veschetti, L., primary, Sandri, A., additional, Saitta, G., additional, Mantovani, R. Passarelli, additional, Burlacchini, G., additional, Preato, S., additional, Sorio, C., additional, Melotti, P., additional, Fiscarelli, E., additional, Signoretto, C., additional, Boaretti, M., additional, Malerba, G., additional, and Lleò, M., additional
- Published
- 2021
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6. 62 Decoding Pseudomonas aeruginosa adaptive response to elexacaftor/tezacaftor/ivacaftor: a multi-omics approach.
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Veschetti, L., Piccolo, S., Vingiani, G., Paganin, C., Fiscarelli, E., Bragonzi, A., and Cigana, C.
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PSEUDOMONAS aeruginosa , *MULTIOMICS - Published
- 2024
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7. P139 Hypermutation as an evolutionary mechanism for Achromobacter spp. in cystic fibrosis lung infection
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Veschetti, L., primary, Sandri, A., additional, Mantovani, R. Passarelli, additional, Melotti, P., additional, Malerba, G., additional, and Lleo, M.M., additional
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- 2020
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8. 391 Gut impairment triggers early-onset airway and systemic diseaserelevant phenotypes in genetically diverse collaborative cross mice with cystic fibrosis.
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Cigana, C., Gianferro, F., Rossi, G., Sanvito, F., Neri, A., Veschetti, L., Facoetti, A., Livraghi-Butrico, A., Ungaro, F., and Bragonzi, A.
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CYSTIC fibrosis , *PHENOTYPES , *MICE - Published
- 2024
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9. Single-Cell RNA Sequencing Analysis Reveals Exercise-Induced Transcriptional Dynamics in Half-Marathon Runners.
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Veschetti L, Patuzzo C, Treccani M, Moron Dalla Tor L, Deiana M, Cheri S, Griggio F, Lippi G, Schena F, De Santis D, Dalle Carbonare L, Tarperi C, Trabetti E, Valenti MT, and Malerba G
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- Humans, Male, Adult, Middle Aged, Transcriptome, Female, Single-Cell Analysis, Sequence Analysis, RNA, Physical Endurance physiology, Marathon Running physiology, Leukocytes, Mononuclear metabolism
- Abstract
Previous studies in sports science suggested that regular exercise has a positive impact on human health. However, the effects of endurance sports and their underlying mechanisms are still not completely understood. One of the main debates regards the modulation of immune dynamics in high-intensity exercise. As part of the "Run 4 Science" project in Verona, Italy, we conducted a single-cell RNA sequencing analysis on half-marathon amateur runners to investigate the transcriptional dynamics of peripheral blood mononuclear cells following endurance exercise. Blood samples were collected from four participants before and after running a half-marathon to carry out a comprehensive transcriptomic analysis of immune cells at the single-cell level. Our analysis revealed significant alterations in the transcriptional profiles following endurance physical exercise. Modulations in myeloid cells suggested the activation of stress response (6 related pathways, p < 0.04) and pathways related to viral processes (4 related pathways, p < 0.03), while in lymphoid cells they hinted to a shift towards immune activation (24 related pathways, p < 0.01). Additionally, transcriptional changes in platelets point to an activation of the coagulation process (5 related pathways, p < 0.005). Single-cell data was also analyzed following a pseudo-bulk approach (i.e., simulating a bulk RNAseq experiment) to gain further biological insights. Our findings suggest that a pseudo-bulk analysis could offer complementary findings to classical single-cell analysis methods and demonstrate that endurance physical exercise, such as running a half-marathon, induces substantial changes in the transcriptional dynamics of immune cells. These insights contribute to a better understanding of the immune modulation mediated by endurance exercise and may inform future training routines or nutritional guidelines based on individual gene expression levels., (© 2025 The Author(s). Scandinavian Journal of Medicine & Science In Sports published by John Wiley & Sons Ltd.)
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- 2025
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10. Genetic and Non-Genetic Contributions to Eosinophilic Granulomatosis with Polyangiitis: Current Knowledge and Future Perspectives.
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Treccani M, Veschetti L, Patuzzo C, Malerba G, Vaglio A, and Martorana D
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In this work, we present a comprehensive overview of the genetic and non-genetic complexity of eosinophilic granulomatosis with polyangiitis (EGPA). EGPA is a rare complex systemic disease that occurs in people presenting with severe asthma and high eosinophilia. After briefly introducing EGPA and its relationship with the anti-neutrophil cytoplasmic autoantibodies (ANCA)-associated vasculitis (AAVs), we delve into the complexity of this disease. At first, the two main biological actors, ANCA and eosinophils, are presented. Biological and clinical phenotypes related to ANCA positivity or negativity are explained, as well as the role of eosinophils and their pathological subtypes, pointing out their intricate relations with EGPA. Then, the genetics of EGPA are described, providing an overview of the research effort to unravel them. Candidate gene studies have investigated biologically relevant candidate genes; the more recent genome-wide association studies and meta-analyses, able to analyze the whole genome, have confirmed previous associations and discovered novel risk loci; in the end, family-based studies have dissected the contribution of rare variants and the heritability of EGPA. Then, we briefly present the environmental contribution to EGPA, reporting seasonal events and pollutants as triggering factors. In the end, the latest omic research is discussed and the most recent epigenomic, transcriptomic and microbiome studies are presented, highlighting the current challenges, open questions and suggesting approaches to unraveling this complex disease.
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- 2024
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11. Dental plaque microbiota sequence counts for microbial profiling and resistance genes detection.
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Veschetti L, Paiella S, Carelli M, Zotti F, Secchettin E, Malleo G, Signoretto C, Zulianello G, Nocini R, Crovetto A, Salvia R, Bassi C, and Malerba G
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- Humans, Drug Resistance, Bacterial genetics, Sequence Analysis, DNA methods, Metagenome, Metagenomics methods, Dental Plaque microbiology, Microbiota genetics, Bacteria genetics, Bacteria classification, Bacteria isolation & purification
- Abstract
Shotgun metagenomics sequencing experiments are finding a wide range of applications. Nonetheless, there are still limited guidelines regarding the number of sequences needed to acquire meaningful information for taxonomic profiling and antimicrobial resistance gene (ARG) identification. In this study, we explored this issue in the context of oral microbiota by sequencing with a very high number of sequences (~ 100 million), four human plaque samples, and one microbial community standard and by evaluating the performance of microbial identification and ARGs detection through a downsampling procedure. When investigating the impact of a decreasing number of sequences on quantitative taxonomic profiling in the microbial community standard datasets, we found some discrepancies in the identified microbial species and their abundances when compared to the expected ones. Such differences were consistent throughout downsampling, suggesting their link to taxonomic profiling methods limitations. Overall, results showed that the number of sequences has a great impact on metagenomic samples at the qualitative (i.e., presence/absence) level in terms of loss of information, especially in experiments having less than 40 million reads, whereas abundance estimation was minimally affected, with only slight variations observed in low-abundance species. The presence of ARGs was also assessed: a total of 133 ARGs were identified. Notably, 23% of them inconsistently resulted as present or absent across downsampling datasets of the same sample. Moreover, over half of ARGs were lost in datasets having less than 20 million reads. This study highlights the importance of carefully considering sequencing aspects and suggests some guidelines for designing shotgun metagenomics experiments with the final goal of maximizing oral microbiome analyses. Our findings suggest varying optimized sequence numbers according to different study aims: 40 million for microbiota profiling, 50 million for low-abundance species detection, and 20 million for ARG identification. KEY POINTS: • Forty million sequences are a cost-efficient solution for microbiota profiling • Fifty million sequences allow low-abundance species detection • Twenty million sequences are recommended for ARG identification., (© 2024. The Author(s).)
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- 2024
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12. Adapting beyond borders: Insights from the 19th Student Council Symposium (SCS2023), the first hybrid ISCB Student Council global event.
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Al Sium SM, Torrejón E, Chowdhury SF, Ahmed R, Jain A, Treccani M, Veschetti L, Riaz A, Eranti P, and Olguín-Orellana GJ
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Summary: The 19th ISCB Student Council Symposium (SCS2023) organized by ISCB-SC adopted a hybrid format for the first time, allowing participants to engage in-person in Lyon, France, and virtually via an interactive online platform. The symposium prioritized inclusivity, featuring on-site sessions, poster presentations, and social activities for in-person attendees, while virtual participants accessed live sessions, interactive Q&A, and a virtual exhibit hall. Attendee statistics revealed a global reach, with Europe as the major contributor. SCS2023's success in bridging in-person and virtual experiences sets a precedent for future events in Computational Biology and Bioinformatics., Availability and Implementation: The details of the symposium, speaker information, schedules, and accepted abstracts, are available in the program booklet (https://doi.org/10.5281/zenodo.8173977). For organizers interested in adopting a similar hybrid model, it would be beneficial to have access to details regarding the online platform used, the types of sessions offered, and the challenges faced. Future iterations of SCS can address these aspects to further enhance accessibility and inclusivity., Competing Interests: None declared., (© The Author(s) 2024. Published by Oxford University Press.)
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- 2024
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13. Start 2024 by asking: 'Why do science?'
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Treccani M and Veschetti L
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- 2024
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14. The Interplay between Microbiota and Human Complex Traits.
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Veschetti L, Treccani M, and Malerba G
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Microorganisms have been one of the most influential drivers propelling some of the greatest environmental and evolutionary changes in the landscape and biology of the entire planet [...].
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- 2023
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15. Genomic Instability Evolutionary Footprints on Human Health: Driving Forces or Side Effects?
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Veschetti L, Treccani M, De Tomi E, and Malerba G
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- Humans, Mutation, Aging genetics, Longevity genetics, DNA Repair, Genomic Instability, Drug-Related Side Effects and Adverse Reactions
- Abstract
In this work, we propose a comprehensive perspective on genomic instability comprising not only the accumulation of mutations but also telomeric shortening, epigenetic alterations and other mechanisms that could contribute to genomic information conservation or corruption. First, we present mechanisms playing a role in genomic instability across the kingdoms of life. Then, we explore the impact of genomic instability on the human being across its evolutionary history and on present-day human health, with a particular focus on aging and complex disorders. Finally, we discuss the role of non-coding RNAs, highlighting future approaches for a better living and an expanded healthy lifespan.
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- 2023
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16. In Vivo Inflammation Caused by Achromobacter spp. Cystic Fibrosis Clinical Isolates Exhibiting Different Pathogenic Characteristics.
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Sandri A, Saitta GM, Veschetti L, Boschi F, Passarelli Mantovani R, Carelli M, Melotti P, Signoretto C, Boaretti M, Malerba G, and Lleò MM
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- Humans, Mice, Animals, Lung microbiology, Inflammation complications, Mice, Knockout, Cystic Fibrosis microbiology, Achromobacter genetics, Pneumonia complications
- Abstract
Achromobacter spp. lung infection in cystic fibrosis has been associated with inflammation, increased frequency of exacerbations, and decline of respiratory function. We aimed to evaluate in vivo the inflammatory effects of clinical isolates exhibiting different pathogenic characteristics. Eight clinical isolates were selected based on different pathogenic characteristics previously assessed: virulence in Galleria mellonella larvae, cytotoxicity in human bronchial epithelial cells, and biofilm formation. Acute lung infection was established by intratracheal instillation with 10.5 × 10
8 bacterial cells in wild-type and CFTR-knockout (KO) mice expressing a luciferase gene under control of interleukin-8 promoter. Lung inflammation was monitored by in vivo bioluminescence imaging up to 48 h after infection, and mortality was recorded up to 96 h. Lung bacterial load was evaluated by CFU count. Virulent isolates caused higher lung inflammation and mice mortality, especially in KO animals. Isolates both virulent and cytotoxic showed higher persistence in mice lungs, while biofilm formation was not associated with lung inflammation, mice mortality, or bacterial persistence. A positive correlation between virulence and lung inflammation was observed. These results indicate that Achromobacter spp. pathogenic characteristics such as virulence and cytotoxicity may be associated with clinically relevant effects and highlight the importance of elucidating their mechanisms.- Published
- 2023
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17. The Emerging Nosocomial Pathogen Klebsiella michiganensis : Genetic Analysis of a KPC-3 Producing Strain Isolated from Venus Clam.
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Simoni S, Leoni F, Veschetti L, Malerba G, Carelli M, Lleò MM, Brenciani A, Morroni G, Giovanetti E, Rocchegiani E, Barchiesi F, and Vignaroli C
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- Carbapenems pharmacology, Plasmids genetics, Microbial Sensitivity Tests, Humans, Klebsiella pneumoniae, Hospitals, Klebsiella, Drug Resistance, Multiple, Bacterial genetics, Phylogeny, Bacterial Proteins genetics, beta-Lactamases genetics, Anti-Bacterial Agents pharmacology, Cross Infection, Klebsiella Infections epidemiology
- Abstract
The recovery and characterization of a multidrug-resistant, KPC-3-producing Klebsiella michiganensis that was obtained from Venus clam samples is reported in this study. A whole-genome sequencing (WGS) analysis using Illumina and Nanopore technologies of the K. michiganensis 23999A2 isolate revealed that the strain belonged to the new sequence type 382 (ST382) and carried seven plasmid replicon sequences, including four IncF type plasmids (FII, FIIY, FIIk, and FIB), one IncHI1 plasmid, and two Col plasmids. The FIB and FII
k plasmids showed high homology to each other and to multireplicon pKpQIL-like plasmids that are found in epidemic KPC-K. pneumoniae clones worldwide. The strain carried multiple β-lactamase genes on the IncF plasmids: blaOXA-9 and blaTEM-1A on FIB, blaKPC-3 inserted in a Tn 4401a on FIIK , and blaSHV-12 on FIIY . The IncHI1-ST11 harbored no resistance gene. The curing of the strain caused the loss of all of the bla genes and a rearrangement of the IncF plasmids. Conjugal transfer of the blaOXA-9 , blaTEM-1A and blaKPC-3 genes occurred at a frequency of 5 × 10-7 , using K. quasipneumoniae as a recipient, and all of the bla genes were transferred through a pKpQIL that originated from the recombination of the FIB and FIIk plasmids of the donor. A comparison with 31 K. michiganensis genomes that are available in the NCBI database showed that the closest phylogenetic relatives of K. michiganensis 23999A2 are an environmental isolate from soil in South Korea and a clinical isolate from human sputum in Japan. Finally, a pan-genome analysis showed a large accessory genome of the strain as well as the great genomic plasticity of the K. michiganensis species. IMPORTANCE Klebsiella michiganensis is an emerging nosocomial pathogen, and, so far, few studies describe isolates of clinical origin in the environment. This study contributes to the understanding of how the dissemination of carbapenem-resistance outside the hospital setting may be related to the circulation of pKpQIL-like plasmids that are derived from epidemic Klebsiella pneumoniae strains. The recovery of a carbapenem-resistant isolate in clams is of great concern, as bivalves could represent vehicles of transmission of pathogens and resistance genes to humans via the food chain. The study demonstrates the plasticity of K. michiganensis genome, which is probably useful to multiple environment adaptation and to the evolution of the species.- Published
- 2023
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18. Detecting Carbapenemases in Animal and Food Samples by Droplet Digital PCR.
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Carelli M, Griggio F, Mingoia M, Garofalo C, Milanović V, Pozzato N, Leoni F, Veschetti L, Malerba G, Sandri A, Patuzzo C, Simoni S, Lleo MM, and Vignaroli C
- Abstract
Background: The presence of carbapenemase-producing bacteria (CPB) in animal hosts and along the food chain may result in the development of reservoirs for human infections. Several CPB strains isolated from animals have been reported, suggesting that transmission and dissemination of the corresponding genes between humans and animals may occur. Animal and food samples have complex backgrounds that hinder the detection of CPB present in low concentrations by standard detection procedures., Methods: We evaluated the possibility of detecting bla
KPC , blaVIM , and blaOXA-48 -like carbapenemases in 286 animal and food samples (faeces from farm and companion animals, raw meat, bivalve molluscs) by culture-based and standard molecular methods and by ddPCR., Results: The proposed ddPCR managed to detect the target genes, also in samples resulting negative to standard methods. While the presence of blaKPC and blaVIM was detected in few samples (~3%), one third of the samples ( n = 94/283) carried different variants of blaOXA-48 -like genes., Conclusion: A specific and sensitive method such as ddPCR could be suitable to evaluate the current veterinarian and environmental situation and to assess the dynamic transmission and persistence of CPB between animals and humans and vice versa.- Published
- 2022
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19. Achromobacter spp. prevalence and adaptation in cystic fibrosis lung infection.
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Veschetti L, Boaretti M, Saitta GM, Passarelli Mantovani R, Lleò MM, Sandri A, and Malerba G
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- Humans, Lung, Prevalence, Achromobacter genetics, Achromobacter denitrificans genetics, Cystic Fibrosis complications, Cystic Fibrosis microbiology, Gram-Negative Bacterial Infections epidemiology, Gram-Negative Bacterial Infections microbiology
- Abstract
Bacteria belonging to the genus Achromobacter are widely distributed in natural environments and have been recognized as emerging pathogens for their contribution to a wide range of human infections. In particular, patients with cystic fibrosis (CF) are the subjects most frequently colonized by Achromobacter spp., which can cause persistent infections in their respiratory tract. Although many clinical aspects and pathogenic mechanisms still remain to be elucidated, Achromobacter spp. have been a source of expanding interest in recent years. This review examines the current literature regarding Achromobacter spp. role in CF, focusing on taxonomy, prevalence in CF lung infections, genomic characteristics, and adaptation strategies including modifications of metabolism and virulence, acquisition of antibiotic resistance, exchange of mobile genetic elements and development of hypermutation., (Copyright © 2022 Elsevier GmbH. All rights reserved.)
- Published
- 2022
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20. Achromobacter spp. Adaptation in Cystic Fibrosis Infection and Candidate Biomarkers of Antimicrobial Resistance.
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Sandri A, Veschetti L, Saitta GM, Passarelli Mantovani R, Carelli M, Burlacchini G, Preato S, Sorio C, Melotti P, Montemari AL, Fiscarelli EV, Patuzzo C, Signoretto C, Boaretti M, Lleò MM, and Malerba G
- Subjects
- Anti-Bacterial Agents pharmacology, Biomarkers, Drug Resistance, Bacterial, Genome-Wide Association Study, Humans, Microbial Sensitivity Tests, Achromobacter genetics, Cystic Fibrosis complications
- Abstract
Achromobacter spp. can establish occasional or chronic lung infections in patients with cystic fibrosis (CF). Chronic colonization has been associated with worse prognosis highlighting the need to identify markers of bacterial persistence. To this purpose, we analyzed phenotypic features of 95 Achromobacter spp. isolates from 38 patients presenting chronic or occasional infection. Virulence was tested in Galleria mellonella larvae, cytotoxicity was tested in human bronchial epithelial cells, biofilm production in static conditions was measured by crystal violet staining and susceptibility to selected antibiotics was tested by the disk diffusion method. The presence of genetic loci associated to the analyzed phenotypic features was evaluated by a genome-wide association study. Isolates from occasional infection induced significantly higher mortality of G. mellonella larvae and showed a trend for lower cytotoxicity than chronic infection isolates. No significant difference was observed in biofilm production among the two groups. Additionally, antibiotic susceptibility testing showed that isolates from chronically-infected patients were significantly more resistant to sulfonamides and meropenem than occasional isolates. Candidate genetic biomarkers associated with antibiotic resistance or sensitivity were identified. Achromobacter spp. strains isolated from people with chronic and occasional lung infection exhibit different virulence and antibiotic susceptibility features, which could be linked to persistence in CF lungs. This underlines the possibility of identifying predictive biomarkers of persistence that could be useful for clinical purposes.
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- 2022
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21. Identification of miRNAs of Strongyloides stercoralis L1 and iL3 larvae isolated from human stool.
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Pomari E, Malerba G, Veschetti L, Franceschi A, Moron Dalla Tor L, Deiana M, Degani M, Mistretta M, Patuzzo C, Ragusa A, Mori A, Bisoffi Z, and Buonfrate D
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- Animals, Feces parasitology, Humans, Larva genetics, RNA, Messenger, MicroRNAs genetics, Strongyloides stercoralis genetics, Strongyloidiasis diagnosis, Strongyloidiasis genetics, Strongyloidiasis parasitology
- Abstract
Strongyloidiasis is a neglected tropical disease caused by the soil-transmitted nematode by Strongyloides stercoralis, that affects approximately 600 million people worldwide. In immunosuppressed individuals disseminated strongyloidiasis can rapidly lead to fatal outcomes. There is no gold standard for diagnosing strongyloidiasis, and infections are frequently misdiagnosed. A better understanding of the molecular biology of this parasite can be useful for example for the discovery of potential new biomarkers. Interestingly, recent evidence showed the presence of small RNAs in Strongyloididae, but no data was provided for S. stercoralis. In this study, we present the first identification of miRNAs of both L1 and iL3 larval stages of S. stercoralis. For our purpose, the aims were: (i) to analyse the miRNome of L1 and iL3 S. stercoralis and to identify potential miRNAs of this nematode, (ii) to obtain the mRNAs profiles in these two larval stages and (iii) to predict potential miRNA target sites in mRNA sequences. Total RNA was isolated from L1 and iL3 collected from the stool of 5 infected individuals. For the miRNAs analysis, we used miRDeep2 software and a pipeline of bio-informatic tools to construct a catalog of a total of 385 sequences. Among these, 53% were common to S. ratti, 19% to S. papillosus, 1% to Caenorhabditis elegans and 44% were novel. Using a differential analysis between the larval stages, we observed 6 suggestive modulated miRNAs (STR-MIR-34A-3P, STR-MIR-8397-3P, STR-MIR-34B-3P and STR-MIR-34C-3P expressed more in iL3, and STR-MIR-7880H-5P and STR-MIR-7880M-5P expressed more in L1). Along with this analysis, we obtained also the mRNAs profiles in the same samples of larvae. Multiple testing found 81 statistically significant mRNAs of the total 1553 obtained (FDR < 0.05; 32 genes expressed more in L1 than iL3; 49 genes expressed more in L3 than iL1). Finally, we found 33 predicted mRNA targets of the modulated miRNAs, providing relevant data for a further validation to better understand the role of these small molecules in the larval stages and their valuein clinical diagnostics., (© 2022. The Author(s).)
- Published
- 2022
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22. Adaptive Interactions of Achromobacter spp. with Pseudomonas aeruginosa in Cystic Fibrosis Chronic Lung Co-Infection.
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Sandri A, Haagensen JAJ, Veschetti L, Johansen HK, Molin S, Malerba G, Signoretto C, Boaretti M, and Lleo MM
- Abstract
In the lungs of patients with cystic fibrosis (CF), the main pathogen Pseudomonas aeruginosa is often co-isolated with other microbes, likely engaging in inter-species interactions. In the case of chronic co-infections, this cohabitation can last for a long time and evolve over time, potentially contributing to the clinical outcome. Interactions involving the emerging pathogens Achromobacter spp. have only rarely been studied, reporting inhibition of P. aeruginosa biofilm formation. To evaluate the possible evolution of such interplay, we assessed the ability of Achromobacter spp. isolates to affect the biofilm formation of co-isolated P. aeruginosa strains during long-term chronic co-infections. We observed both competition and cohabitation. An Achromobacter sp. isolate secreted exoproducts interfering with the adhesion ability of a co-isolated P. aeruginosa strain and affected its biofilm formation. Conversely, a clonal Achromobacter sp. strain later isolated from the same patient, as well as two longitudinal strains from another patient, did not show similar competitive behavior against its P. aeruginosa co-isolates. Genetic variants supporting the higher virulence of the competitive Achromobacter sp. isolate were found in its genome. Our results confirm that both inter-species competition and cohabitation are represented during chronic co-infections in CF airways, and evolution of these interplays can happen even at the late stages of chronic infection.
- Published
- 2021
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23. Genomic characterization of Achromobacter species isolates from chronic and occasional lung infection in cystic fibrosis patients.
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Veschetti L, Sandri A, Patuzzo C, Melotti P, Malerba G, and Lleo MM
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- Achromobacter isolation & purification, Drug Resistance, Bacterial genetics, Humans, Lung microbiology, MutS Proteins genetics, Virulence Factors genetics, Whole Genome Sequencing, beta-Lactamases genetics, Achromobacter classification, Achromobacter genetics, Cystic Fibrosis microbiology, Genome, Bacterial genetics, Gram-Negative Bacterial Infections microbiology, Persistent Infection microbiology
- Abstract
Achromobacter species are increasingly being detected in cystic fibrosis (CF) patients, where they can establish chronic infections by adapting to the lower airway environment. To better understand the mechanisms contributing to a successful colonization by Achromobacter species, we sequenced the whole genome of 54 isolates from 26 patients with occasional and early/late chronic lung infection. We performed a phylogenetic analysis and compared virulence and resistance genes, genetic variants and mutations, and hypermutability mechanisms between chronic and occasional isolates. We identified five Achromobacter species as well as two non-affiliated genogroups (NGs). Among them were the frequently isolated Achromobacter xylosoxidans and four other species whose clinical importance is not yet clear: Achromobacter insuavis, Achromobacter dolens, Achromobacter insolitus and Achromobacter aegrifaciens . While A. insuavis and A. dolens were isolated only from chronically infected patients and A. aegrifaciens only from occasionally infected patients, the other species were found in both groups. Most of the occasional isolates lacked functional genes involved in invasiveness, chemotaxis, type 3 secretion system and anaerobic growth, whereas the great majority (>60%) of chronic isolates had these genomic features. Interestingly, almost all ( n =22/23) late chronic isolates lacked functional genes involved in lipopolysaccharide production. Regarding antibiotic resistance, we observed a species-specific distribution of blaOXA genes, confirming what has been reported in the literature and additionally identifying blaOXA-2 in some A. insolitus isolates and observing no blaOXA genes in A. aegrifaciens or NGs. No significant difference in resistance genes was found between chronic and occasional isolates. The results of the mutator genes analysis showed that no occasional isolate had hypermutator characteristics, while 60% of early chronic (<1 year from first colonization) and 78% of late chronic (>1 year from first colonization) isolates were classified as hypermutators. Although all A. dolens, A. insuavis and NG isolates presented two different mutS genes, these seem to have a complementary rather than compensatory function. In conclusion, our results show that Achromobacter species can exhibit different adaptive mechanisms and some of these mechanisms might be more useful than others in establishing a chronic infection in CF patients, highlighting their importance for the clinical setting and the need for further studies on the less clinically characterized Achromobacter species.
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- 2021
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24. Mobilome Analysis of Achromobacter spp. Isolates from Chronic and Occasional Lung Infection in Cystic Fibrosis Patients.
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Veschetti L, Sandri A, Patuzzo C, Melotti P, Malerba G, and Lleò MM
- Abstract
Achromobacter spp. is an opportunistic pathogen that can cause lung infections in patients with cystic fibrosis (CF). Although a variety of mobile genetic elements (MGEs) carrying antimicrobial resistance genes have been identified in clinical isolates, little is known about the contribution of Achromobacter spp. mobilome to its pathogenicity. To provide new insights, we performed bioinformatic analyses of 54 whole genome sequences and investigated the presence of phages, insertion sequences (ISs), and integrative and conjugative elements (ICEs). Most of the detected phages were previously described in other pathogens and carried type II toxin-antitoxin systems as well as other pathogenic genes. Interestingly, the partial sequence of phage Bcep176 was found in all the analyzed Achromobacter xylosoxidans genome sequences, suggesting the integration of this phage in an ancestor strain. A wide variety of IS was also identified either inside of or in proximity to pathogenicity islands. Finally, ICEs carrying pathogenic genes were found to be widespread among our isolates and seemed to be involved in transfer events within the CF lung. These results highlight the contribution of MGEs to the pathogenicity of Achromobacter species, their potential to become antimicrobial targets, and the need for further studies to better elucidate their clinical impact.
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- 2021
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25. Shewanella algae and Vibrio spp. strains isolated in Italian aquaculture farms are reservoirs of antibiotic resistant genes that might constitute a risk for human health.
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Zago V, Veschetti L, Patuzzo C, Malerba G, and Lleo MM
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- Anti-Bacterial Agents, Genes, Bacterial, Humans, Italy, Microbial Sensitivity Tests, Phylogeny, Shewanella, beta-Lactamases, Aquaculture, Drug Resistance, Bacterial genetics, Environmental Exposure statistics & numerical data, Vibrio
- Abstract
The aquatic environment can represent a reservoir of antimicrobial resistance genes. In the present study, phenotypical, biochemical and molecular techniques were used to screen a collection of marine strains isolated in Italian aquaculture farms to investigate their beta-lactam resistance profiles. The genome of 12 carbapenemase and/or beta-lactamase producing strains was sequenced and a phylogenetic analysis of the beta-lactamases found in their chromosomes was performed. Gene annotation and prediction revealed the presence of bla
AmpC and blaOXA-55-like in all the Shewanella algae isolates whereas in Vibrio anguillarum and Vibrio parahaemolyticus strains, blaAmpC and blaCARB-19 were found, respectively. Multiple alignments of OXA-55-like and AmpC protein sequences showed different point mutations. Finally, comparisons between enzyme phylogeny and strain clusterization based on sampling sites and dates indicate the diffusion of specific Multi Drug Resistant (MDR) Shewanella algae clones along the Italian Adriatic coast., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)- Published
- 2020
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26. Resistome, Mobilome and Virulome Analysis of Shewanella algae and Vibrio spp. Strains Isolated in Italian Aquaculture Centers.
- Author
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Zago V, Veschetti L, Patuzzo C, Malerba G, and Lleo MM
- Abstract
Antimicrobial resistance is a major public health concern restricted not only to healthcare settings but also to veterinary and environmental ones. In this study, we analyzed, by whole genome sequencing (WGS) the resistome, mobilome and virulome of 12 multidrug-resistant (MDR) marine strains belonging to Shewanellaceae and Vibrionaceae families collected at aquaculture centers in Italy. The results evidenced the presence of several resistance mechanisms including enzyme and efflux pump systems conferring resistance to beta-lactams, quinolones, tetracyclines, macrolides, polymyxins, chloramphenicol, fosfomycin, erythromycin, detergents and heavy metals. Mobilome analysis did not find circular elements but class I integrons, integrative and conjugative element (ICE) associated modules, prophages and different insertion sequence (IS) family transposases. These mobile genetic elements (MGEs) are usually present in other aquatic bacteria but also in Enterobacteriaceae suggesting their transferability among autochthonous and allochthonous bacteria of the resilient microbiota. Regarding the presence of virulence factors, hemolytic activity was detected both in the Shewanella algae and in Vibrio spp. strains. To conclude, these data indicate the role as a reservoir of resistance and virulence genes in the environment of the aquatic microbiota present in the examined Italian fish farms that potentially might be transferred to bacteria of medical interest.
- Published
- 2020
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27. Hypermutation as an Evolutionary Mechanism for Achromobacter xylosoxidans in Cystic Fibrosis Lung Infection.
- Author
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Veschetti L, Sandri A, Johansen HK, Lleò MM, and Malerba G
- Abstract
Achromobacter xylosoxidans can cause chronic infections in the lungs of patients with cystic fibrosis (CF) by adapting to the specific environment. The study of longitudinal isolates allows to investigate its within-host evolution to unravel the adaptive mechanisms contributing to successful colonization. In this study, four clinical isolates longitudinally collected from two chronically infected patients underwent whole genome sequencing, de novo assembly and sequence analysis. Phenotypic assays were also performed. The isolates coming from one of the patients (patient A) presented a greater number of genetic variants, diverse integrative and conjugative elements, and different protease secretion. In the first of these isolates (strain A1), we also found a large deletion in the mutS gene, involved in DNA mismatch repair (MMR). In contrast, isolates from patient B showed a lower number of variants, only one integrative and mobilizable element, no phenotypic changes, and no mutations in the MMR system. These results suggest that in the two patients the establishment of a chronic infection was mediated by different adaptive mechanisms. While the strains isolated from patient B showed a longitudinal microevolution, strain A1 can be clearly classified as a hypermutator, confirming the occurrence and importance of this adaptive mechanism in A. xylosoxidans infection., Competing Interests: The authors declare no conflict of interest.
- Published
- 2020
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