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1.
Genome Med ; 16(1): 61, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38659008

RESUMEN

BACKGROUND: Implementation of clinical metagenomics and pathogen genomic surveillance can be particularly challenging due to the lack of bioinformatics tools and/or expertise. In order to face this challenge, we have previously developed INSaFLU, a free web-based bioinformatics platform for virus next-generation sequencing data analysis. Here, we considerably expanded its genomic surveillance component and developed a new module (TELEVIR) for metagenomic virus identification. RESULTS: The routine genomic surveillance component was strengthened with new workflows and functionalities, including (i) a reference-based genome assembly pipeline for Oxford Nanopore technologies (ONT) data; (ii) automated SARS-CoV-2 lineage classification; (iii) Nextclade analysis; (iv) Nextstrain phylogeographic and temporal analysis (SARS-CoV-2, human and avian influenza, monkeypox, respiratory syncytial virus (RSV A/B), as well as a "generic" build for other viruses); and (v) algn2pheno for screening mutations of interest. Both INSaFLU pipelines for reference-based consensus generation (Illumina and ONT) were benchmarked against commonly used command line bioinformatics workflows for SARS-CoV-2, and an INSaFLU snakemake version was released. In parallel, a new module (TELEVIR) for virus detection was developed, after extensive benchmarking of state-of-the-art metagenomics software and following up-to-date recommendations and practices in the field. TELEVIR allows running complex workflows, covering several combinations of steps (e.g., with/without viral enrichment or host depletion), classification software (e.g., Kaiju, Kraken2, Centrifuge, FastViromeExplorer), and databases (RefSeq viral genome, Virosaurus, etc.), while culminating in user- and diagnosis-oriented reports. Finally, to potentiate real-time virus detection during ONT runs, we developed findONTime, a tool aimed at reducing costs and the time between sample reception and diagnosis. CONCLUSIONS: The accessibility, versatility, and functionality of INSaFLU-TELEVIR are expected to supply public and animal health laboratories and researchers with a user-oriented and pan-viral bioinformatics framework that promotes a strengthened and timely viral metagenomic detection and routine genomics surveillance. INSaFLU-TELEVIR is compatible with Illumina, Ion Torrent, and ONT data and is freely available at https://insaflu.insa.pt/ (online tool) and https://github.com/INSaFLU (code).


Asunto(s)
COVID-19 , Biología Computacional , Genoma Viral , Metagenómica , SARS-CoV-2 , Programas Informáticos , Metagenómica/métodos , Humanos , SARS-CoV-2/genética , SARS-CoV-2/clasificación , COVID-19/virología , Biología Computacional/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Internet , Genómica/métodos
2.
Euro Surveill ; 28(36)2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37676143

RESUMEN

Since autumn 2022, observed numbers of paediatric invasive group A Streptococcus infections in Portugal (n = 89) were higher than in pre-COVID-19 seasons. Between September 2022 and May 2023, the dominant diagnoses were pneumonia (25/79), mostly with empyema (20/25), and sepsis (22/79). A number of cases required admission to intensive care (27/79) and surgery (35/79), and the case fatality rate was 5.1% (4/79). Genomic sequencing (n = 55) revealed multiple genetic lineages, dominated by the M1UK sublineage (26/55) and more diverse emm12 isolates (12/55).


Asunto(s)
COVID-19 , Infecciones Estreptocócicas , Humanos , Niño , Portugal/epidemiología , Streptococcus pyogenes/genética , Mapeo Cromosómico , Infecciones Estreptocócicas/diagnóstico , Infecciones Estreptocócicas/epidemiología , Reino Unido
3.
Microb Genom ; 8(3)2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35259087

RESUMEN

Computational algorithms have become an essential component of research, with great efforts by the scientific community to raise standards on development and distribution of code. Despite these efforts, sustainability and reproducibility are major issues since continued validation through software testing is still not a widely adopted practice. Here, we report seven recommendations that help researchers implement software testing in microbial bioinformatics. We have developed these recommendations based on our experience from a collaborative hackathon organised prior to the American Society for Microbiology Next Generation Sequencing (ASM NGS) 2020 conference. We also present a repository hosting examples and guidelines for testing, available from https://github.com/microbinfie-hackathon2020/CSIS.


Asunto(s)
Biología Computacional , Programas Informáticos , Algoritmos , Secuenciación de Nucleótidos de Alto Rendimiento , Reproducibilidad de los Resultados , Estados Unidos
4.
Sci Rep ; 11(1): 23720, 2021 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-34887473

RESUMEN

Machine learning (ML) algorithms were explored for the classification of the UV-Vis absorption spectrum of organic molecules based on molecular descriptors and fingerprints generated from 2D chemical structures. Training and test data (~ 75 k molecules and associated UV-Vis data) were assembled from a database with lists of experimental absorption maxima. They were labeled with positive class (related to photoreactive potential) if an absorption maximum is reported in the range between 290 and 700 nm (UV/Vis) with molar extinction coefficient (MEC) above 1000 Lmol-1 cm-1, and as negative if no such a peak is in the list. Random forests were selected among several algorithms. The models were validated with two external test sets comprising 998 organic molecules, obtaining a global accuracy up to 0.89, sensitivity of 0.90 and specificity of 0.88. The ML output (UV-Vis spectrum class) was explored as a predictor of the 3T3 NRU phototoxicity in vitro assay for a set of 43 molecules. Comparable results were observed with the classification directly based on experimental UV-Vis data in the same format.

5.
J Med Primatol ; 50(6): 313-322, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34558078

RESUMEN

BACKGROUND: Acanthocephalosis is an important cause of death in captive New World primates (NWP). Once established in a colony, it is extremely difficult to treat and control, quickly spreading among NWP with a high mortality rate. This study aimed to characterize the disease associated with infection with acanthocephalans according to its epidemiological, clinical, and anatomopathological aspects in a captive NWP population. METHODS: From 2010 to 2020, a Brazilian zoo had recurrent deaths of NWP associated to acanthocephalan parasitism. Clinical and pathological profiles of these animals were analyzed considering the host species, sex, age, weight, clinical signs, therapeutic protocols, and pathological findings. RESULTS: A total of 27 deaths associated with acanthocephalosis were recorded, all lethal cases affected tamarins and lion tamarins, corresponding to 67.5% of total deaths during the course of this study. Ten animals died with no previously detected clinical signs, whereas cases with noticeable clinical signs often had apathy and progressive weight loss, resulting in cachexia. Symptomatic NWP were treated with anthelmintic protocols, antibiotics, and support therapy. However, all hospitalized animals died and had grossly detectable adult acanthocephalans in the intestinal lumen that were identified as Prosthenorchis sp., which were associated with transmural and ulcerative enteritis. CONCLUSIONS: This report revealed the impact of acanthocephalosis in a naturally infected captive colony of NWP, particularly affecting tamarins (Saguinus spp.) and lion tamarins (Leontopithecus spp.), with failed treatment and control strategies.


Asunto(s)
Leontopithecus , Enfermedades de los Monos , Animales , Brasil/epidemiología , Enfermedades de los Monos/epidemiología , Saguinus
6.
Int J Genomics ; 2021: 6636138, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33869622

RESUMEN

Listeria monocytogenes sequence type 1247 clonal complex 8 caused a prolonged multicountry outbreak in five EU countries: Denmark, Estonia, Finland, France, and Sweden. A total of 22 disease cases were identified with onset of symptoms between July 2014 and February 2019. Five patients died due to, or with, the disease. The retrospective analysis of L. monocytogenes isolate VLTRLM2013 revealed the presence of an outbreak-related strain (cgMLST type L2-SL8-ST1247-CT4158) in ready-to-eat fish product more than a year prior to the first outbreak-related cases. Reference outbreak strain and VLTRLM2013 strain were compared using core genome and whole-genome multilocus sequence typing analyses. Genomic level differences of the persistent L. monocytogenes strains associated with a prolonged multicountry foodborne listeriosis outbreak are described. It was concluded that the persistent nature of the multicountry outbreak-related L. monocytogenes strain VLTRLM2013 together with stress island, virulence, and antibiotic resistance genes could potentially be the determining factors for the extensive and prolonged outbreak affecting five European Union countries. Our results support the systematic application of whole-genome sequencing in food and public health surveillance and further encourages its wide adoption.

7.
Nucleic Acids Res ; 49(D1): D660-D666, 2021 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-33068420

RESUMEN

Chewie Nomenclature Server (chewie-NS, https://chewbbaca.online/) allows users to share genome-based gene-by-gene typing schemas and to maintain a common nomenclature, simplifying the comparison of results. The combination between local analyses and a public repository of allelic data strikes a balance between potential confidentiality issues and the need to compare results. The possibility of deploying private instances of chewie-NS facilitates the creation of nomenclature servers with a restricted user base to allow compliance with the strictest data policies. Chewie-NS allows users to easily share their own schemas and to explore publicly available schemas, including informative statistics on schemas and loci presented in interactive charts and tables. Users can retrieve all the information necessary to run a schema locally or all the alleles identified at a particular locus. The integration with the chewBBACA suite enables users to directly upload new schemas to chewie-NS, download existing schemas and synchronize local and remote schemas from chewBBACA command line version, allowing an easier integration into high-throughput analysis pipelines. The same REST API linking chewie-NS and the chewBBACA suite supports the interaction of other interfaces or pipelines with the databases available at chewie-NS, facilitating the reusability of the stored data.


Asunto(s)
Genoma , Difusión de la Información , Tipificación de Secuencias Multilocus , Terminología como Asunto , Interfaz Usuario-Computador
8.
J Chem Inf Model ; 61(1): 67-75, 2021 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-33350814

RESUMEN

In this study, machine learning algorithms were investigated for the classification of organic molecules with one carbon chiral center according to the sign of optical rotation. Diverse heterogeneous data sets comprising up to 13,080 compounds and their corresponding optical rotation were retrieved from Reaxys and processed independently for three solvents: dichloromethane, chloroform, and methanol. The molecular structures were represented by chiral descriptors based on the physicochemical and topological properties of ligands attached to the chiral center. The sign of optical rotation was predicted by random forests (RF) and artificial neural networks for independent test sets with an accuracy of up to 75% for dichloromethane, 82% for chloroform, and 82% for methanol. RF probabilities and the availability of structures in the training set with the same spheres of atom types around the chiral center defined applicability domains in which the accuracy is higher.


Asunto(s)
Aprendizaje Automático , Redes Neurales de la Computación , Algoritmos , Estructura Molecular , Rotación Óptica , Estereoisomerismo
9.
J Antimicrob Chemother ; 75(2): 296-299, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31740946

RESUMEN

OBJECTIVES: Streptococcus agalactiae [group B streptococci (GBS)] have been considered uniformly susceptible to penicillin. However, increasing reports from Asia and North America are documenting penicillin-non-susceptible GBS (PRGBS) with mutations in pbp genes. Here we report, to the best of our knowledge, the first two PRGBS isolates recovered in Europe (AC-13238-1 and AC-13238-2), isolated from the same patient. METHODS: Two different colony morphologies of GBS were noted from a surgical abscess drainage sample. Both were serotyped and antimicrobial susceptibility testing was performed by different methodologies. High-throughput sequencing was done to compare the isolates at the genomic level, to identify their capsular type and ST, to evaluate mutations in the pbp genes and to compare the isolates with the genomes of other PRGBS isolates sharing the same serotype and ST. RESULTS: Isolates AC-13238-1 and AC-13238-2 presented MICs above the EUCAST and CLSI breakpoints for penicillin susceptibility. Both shared the capsular type Ia operon and ST23. Genomic analysis uncovered differences between the two isolates in seven genes, including altered pbp genes. Deduced amino acid sequences revealed critical substitutions in PBP2X in both isolates. Comparison with serotype Ia clonal complex 23 PRGBS from the USA reinforced the similarity between AC-13238-1 and AC-13238-2, and their divergence from the US strains. CONCLUSIONS: Our results support the in-host evolution of ß-lactam-resistant GBS, with two PRGBS variants being isolated from one patient.


Asunto(s)
Resistencia a las Penicilinas , Infecciones Estreptocócicas , Streptococcus agalactiae , Antibacterianos/farmacología , Alemania , Humanos , Pruebas de Sensibilidad Microbiana , Penicilinas , Infecciones Estreptocócicas/microbiología , Streptococcus agalactiae/genética , Streptococcus agalactiae/aislamiento & purificación
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