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1.
Gynecol Oncol ; 162(1): 97-106, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33858678

RESUMEN

BACKGROUND: Up to 20% of high-grade serous ovarian carcinomas (HGSOC) are hereditary; however, historical uptake of genetic testing is low. We used a unique combination of approaches to identify women in Ontario, Canada, with a first-degree relative (FDR) who died from HGSOC without prior genetic testing, and offer them multi-gene panel testing. METHODS: From May 2015-Sept 2019, genetic counseling and testing was provided to eligible participants. Two recruitment strategies were employed, including self-identification in response to an outreach campaign and direct targeting of FDRs of deceased HGSOC patients treated at our institution. The rate of pathogenic variants (PV) in established/potential ovarian cancer risk genes and the benefits/challenges of each approach were assessed. RESULTS: A total of 564 women enrolled in response to our outreach campaign (n = 473) or direct recruitment (n = 91). Mean age at consent was 52 years and 96% did not meet provincial testing criteria. Genetic results were provided to 528 individuals from 458 families. The rate of PVs in ovarian cancer risk genes was highest when FDRs were diagnosed with HGSOC <60 years (9.4% vs. 3.9% ≥ 60y, p = 0.0160). Participants in the outreach vs. direct recruitment cohort had a similar rate of PVs; however, uptake of genetic testing (97% vs. 89%; p = 0.0036) and study completion (95% vs. 87%; p = 0.0062) rates were higher in the former. Eleven participants with pathogenic variants have completed risk-reducing gynecologic surgery, with one stage I HGSOC and two breast cancers identified. CONCLUSION: Overall PV rates in this large cohort were lower than expected; however, we provide evidence that genetic testing criteria in Ontario should include individuals with a deceased FDR diagnosed with HGSOC <60 years of age.


Asunto(s)
Carcinoma Epitelial de Ovario/genética , Carcinoma Epitelial de Ovario/prevención & control , Pruebas Genéticas/métodos , Neoplasias Ováricas/genética , Neoplasias Ováricas/prevención & control , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Predisposición Genética a la Enfermedad , Humanos , Persona de Mediana Edad , Ontario , Selección de Paciente , Guías de Práctica Clínica como Asunto , Estudios Prospectivos , Factores de Riesgo , Adulto Joven
2.
Gynecol Oncol ; 153(1): 108-115, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30638766

RESUMEN

OBJECTIVE: Genetic testing identifies cancer patients who may benefit from targeted treatment and allows for enhanced cancer screening and risk-reduction in their at-risk relatives. Traditional models of genetic counseling (GC) cannot meet the increasing demand and urgency for genetic testing. The objective of this study was to evaluate a new model of service delivery to improve the efficiency of pre-test GC for panel-based genetic testing. METHODS: A parallel, two-armed, randomized non-inferiority study compared traditional and modified pre-test GC models (1:2) prior to panel-based genetic testing. Participants were adult females, whose first-degree relative died of serous ovarian cancer. In the modified group, participants were emailed a 20-minute presentation prior to a scheduled pre-test GC telephone call. Psychosocial and knowledge questionnaires were provided at baseline (P1) and one week after pre-test GC (P2). RESULTS: 382 women completed pre-test GC (256 modified, 126 traditional). There were no differences in marital status, education level or household income. Pre-test GC time was shorter in the modified group (average 19 vs. 46 min, p < 0.001), with no difference in post-test GC time (average 16 min each, p = 0.78). The modified pre-test GC model was found to be non-inferior to traditional GC on measures of cancer-specific distress, depression, anxiety, decisional conflict, ovarian cancer knowledge and satisfaction. Perceived lifetime risk for ovarian cancer decreased to a lesser extent from baseline in women who received modified pre-test GC. CONCLUSIONS: A 20-minute presentation prior to pre-test telephone GC is non-inferior to traditional in-person GC on all variables tested, except for perceived ovarian cancer risk. This modified model improved GC efficiency without negatively affecting psychosocial outcomes, providing an alternative strategy to meet the growing demand for genetic testing.


Asunto(s)
Asesoramiento Genético/métodos , Neoplasias Ováricas/genética , Neoplasias Ováricas/psicología , Técnicas de Apoyo para la Decisión , Femenino , Asesoramiento Genético/psicología , Predisposición Genética a la Enfermedad/psicología , Pruebas Genéticas/métodos , Humanos , Persona de Mediana Edad , Modelos Psicológicos
3.
Immunohorizons ; 8(9): 635-651, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39248806

RESUMEN

Cattle produce Abs with an H chain ultralong CDR3 (40-70 aa). These Abs have been shown to have features such as broad neutralization of viruses and are investigated as human therapeutics. A common issue in sequencing the bovine BCR repertoire is the sequence length required to capture variable (V) and isotype gene information. This study aimed to assess the use of Oxford Nanopore Technologies' MinION platform to perform IgM BCR repertoire sequencing to assess variation in the percentage of ultralong CDR3s among dairy cattle. Blood was collected from nine Holstein heifers. B cells were isolated using magnetic bead-based separation, RNA was extracted, and IgM+ transcripts were amplified using PCR and sequenced using a MinION R10.4 flow cell. The distribution of CDR3 lengths was trimodal, and the percentage of ultralong CDR3s ranged among animals from 2.32 to 20.13% in DNA sequences and 1.56% to 17.02% in productive protein sequences. V segment usage varied significantly among heifers. Segment IGHV1-7, associated with ultralong CDR3s, was used in 5.8-24.2% of sequences; usage was positively correlated with ultralong CDR3 production (r = 0.99, p < 0.01). To our knowledge, this is the first study to sequence the bovine BCR repertoire using Oxford Nanopore Technologies and demonstrates the potential for cost-efficient long-read repertoire sequencing in cattle without assembly. Findings from this study support literature describing the distribution of length and percentage of ultralong CDR3s. Future studies will investigate changes in the bovine BCR repertoire associated with age, antigenic exposure, and genetics.


Asunto(s)
Linfocitos B , Regiones Determinantes de Complementariedad , Inmunoglobulina M , Receptores de Antígenos de Linfocitos B , Animales , Bovinos , Regiones Determinantes de Complementariedad/genética , Regiones Determinantes de Complementariedad/inmunología , Receptores de Antígenos de Linfocitos B/genética , Receptores de Antígenos de Linfocitos B/inmunología , Inmunoglobulina M/inmunología , Inmunoglobulina M/sangre , Linfocitos B/inmunología , Femenino , Nanoporos , Análisis de Secuencia de ADN
4.
Front Vet Sci ; 11: 1443855, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39144078

RESUMEN

Introduction: Spillover events of Mycoplasma ovipneumoniae have devastating effects on the wild sheep populations. Multilocus sequence typing (MLST) is used to monitor spillover events and the spread of M. ovipneumoniae between the sheep populations. Most studies involving the typing of M. ovipneumoniae have used Sanger sequencing. However, this technology is time-consuming, expensive, and is not well suited to efficient batch sample processing. Methods: Our study aimed to develop and validate an MLST workflow for typing of M. ovipneumoniae using Nanopore Rapid Barcoding sequencing and multiplex polymerase chain reaction (PCR). We compare the workflow with Nanopore Native Barcoding library preparation and Illumina MiSeq amplicon protocols to determine the most accurate and cost-effective method for sequencing multiplex amplicons. A multiplex PCR was optimized for four housekeeping genes of M. ovipneumoniae using archived DNA samples (N = 68) from nasal swabs. Results: Sequences recovered from Nanopore Rapid Barcoding correctly identified all MLST types with the shortest total workflow time and lowest cost per sample when compared with Nanopore Native Barcoding and Illumina MiSeq methods. Discussion: Our proposed workflow is a convenient and effective method for strain typing of M. ovipneumoniae and can be applied to other bacterial MLST schemes. The workflow is suitable for diagnostic settings, where reduced hands-on time, cost, and multiplexing capabilities are important.

6.
Microbiol Spectr ; 11(6): e0172223, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-37815394

RESUMEN

IMPORTANCE: The swine gut microbiome undergoes an age-dependent assembly pattern with a developmental phase at early ages and a stabilization phase at later ages. Shorter time intervals and a wider range of data sources provided a clearer understanding of the gut microbiota colonization and succession and their associations with pig growth and development. The rapidly changing microbiota of suckling and weaning pigs implies potential time targets for growth and health regulation through gut microbiota manipulation. Since swine gut microbiota development is predictable, swine microbiota age can be calculated and compared between animal treatment groups rather than relying only on static time-matched comparisons.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Porcinos , Animales , Microbioma Gastrointestinal/fisiología , ARN Ribosómico 16S , Destete
7.
Nature ; 441(7089): 91-5, 2006 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-16672971

RESUMEN

Small-molecule inhibitors of protein function are powerful tools for biological analysis and can lead to the development of new drugs. However, a major bottleneck in generating useful small-molecule tools is target identification. Here we show that Caenorhabditis elegans can provide a platform for both the discovery of new bioactive compounds and target identification. We screened 14,100 small molecules for bioactivity in wild-type worms and identified 308 compounds that induce a variety of phenotypes. One compound that we named nemadipine-A induces marked defects in morphology and egg-laying. Nemadipine-A resembles a class of widely prescribed anti-hypertension drugs called the 1,4-dihydropyridines (DHPs) that antagonize the alpha1-subunit of L-type calcium channels. Through a genetic suppressor screen, we identified egl-19 as the sole candidate target of nemadipine-A, a conclusion that is supported by several additional lines of evidence. egl-19 encodes the only L-type calcium channel alpha1-subunit in the C. elegans genome. We show that nemadipine-A can also antagonize vertebrate L-type calcium channels, demonstrating that worms and vertebrates share the orthologous protein target. Conversely, FDA-approved DHPs fail to elicit robust phenotypes, making nemadipine-A a unique tool to screen for genetic interactions with this important class of drugs. Finally, we demonstrate the utility of nemadipine-A by using it to reveal redundancy among three calcium channels in the egg-laying circuit. Our study demonstrates that C. elegans enables rapid identification of new small-molecule tools and their targets.


Asunto(s)
Caenorhabditis elegans/efectos de los fármacos , Bloqueadores de los Canales de Calcio/aislamiento & purificación , Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio Tipo L/metabolismo , Evaluación Preclínica de Medicamentos/métodos , Piridinas/farmacología , Animales , Caenorhabditis elegans/embriología , Caenorhabditis elegans/genética , Caenorhabditis elegans/fisiología , Bloqueadores de los Canales de Calcio/química , Bloqueadores de los Canales de Calcio/farmacocinética , Felodipino/aislamiento & purificación , Felodipino/farmacocinética , Felodipino/farmacología , Oviposición/efectos de los fármacos , Fenotipo , Piridinas/química , Piridinas/aislamiento & purificación
8.
Anim Microbiome ; 4(1): 10, 2022 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-35063043

RESUMEN

BACKGROUND: The tonsil of the soft palate in pigs is the colonization site of both commensal and pathogenic microbial agents. Streptococcus suis infections are a significant economic problem in the swine industry. The development of S. suis disease remains poorly understood. The purpose of this study was to identify whether the tonsillar microbiota profile in nursery pigs is altered with S. suis disease. Here, the dynamics of the tonsillar microbiota from 20 healthy pigs and 43 diseased pigs with S. suis clinical signs was characterized. RESULTS: Based on the presence or absence of S. suis in the systemic sites, diseased pigs were classified into confirmed (n = 20) or probable (n = 23) group, respectively. Microbiota composition was assessed using the V3-V4 hypervariable region of the 16S rRNA, and results were analyzed to identify the diversity of the tonsillar microbiota. The taxonomic composition of the tonsil microbiota proved to be highly diverse between individuals, and the results showed statistically significant microbial community structure among the diagnosis groups. The confirmed group had the lowest observed species richness while the probable group had higher phylogenetics diversity level compared to the healthy group. Un-weighted Unifrac also demonstrated that the probable group had a higher beta diversity than both the healthy and the confirmed group. A Dirichlet-multinomial mixture (DMM) model-based clustering method partitioned the tonsil microbiota into two distinct community types that did not correspond with disease status. However, there was an association between Streptococcus suis serotype 2 and DMM community type 1 (p = 0.03). ANCOM-BC identified 24 Streptococcus amplicon sequence variants (ASVs) that were differentially abundant between the DMM community types. CONCLUSIONS: This study provides a comprehensive analysis of the structure and membership of the tonsil microbiota in nursery pigs and uncovers differences and similarities across varying S. suis disease status. While the overall abundance of Streptococcus was not different among the diagnosis groups, the unique profile of DMM community type 1 and the observed correlation with S. suis serotype 2 could provide insight into potential tonsillar microbiota involvement in S. suis disease.

9.
Antibiotics (Basel) ; 11(2)2022 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-35203784

RESUMEN

IncI2 plasmids appear to have only recently become associated with resistance genes; however, their tendency to carry resistance to the antibiotics of last resort and their widespread distribution increase their relative importance. In this study, we describe lineages within this plasmid family that have an increased likelihood of acquisition of antimicrobial resistance genes. Globally distributed mcr-1-carrying IncI2 plasmids were found to cluster with other IncI2 plasmids carrying extended-spectrum beta-lactamase genes, and separately from the non-resistant IncI2 plasmids. In addition, insertion sequence (IS) elements with no direct association with the acquired resistance genes also clustered with the resistance plasmids in the phylogenetic tree. In recognition of the biased sequencing of resistant plasmids globally, the analysis was also performed on resistant and non-resistant IncI2 plasmids sequenced in the USA through government surveillance efforts that do not rely on antibiotic selection. This analysis confirmed a distinct clustering associated with both resistance and mobile elements and identified possible genomic changes in core genes that correlate with increased acquisition of foreign DNA. This work highlights a potential genetic mechanism for increased uptake of foreign DNA within this prevalent family of plasmids.

10.
Viruses ; 14(10)2022 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-36298766

RESUMEN

Aquatic bird bornavirus 1 (ABBV-1) is a neurotropic virus that infects waterfowls, resulting in persistent infection. Experimental infection showed that both Muscovy ducks and chickens support persistent ABBV-1 infection in the central nervous system (CNS), up to 12 weeks post-infection (wpi), without the development of clinical disease. The aim of the present study was to describe the transcriptomic profiles in the brains of experimentally infected Muscovy ducks and chickens infected with ABBV-1 at 4 and 12 wpi. Transcribed RNA was sequenced by next-generation sequencing and analyzed by principal component analysis (PCA) and differential gene expression. The functional annotation of differentially expressed genes was evaluated by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. The PCA showed that the infected ducks sampled at both 4 and 12 wpi clustered separately from the controls, while only the samples from the chickens at 12 wpi, but not at 4 wpi, formed a separate cluster. In the ducks, more genes were differentially expressed at 4 wpi than 12 wpi, and the majority of the highly differentially expressed genes (DEG) were upregulated. On the other hand, the infected chickens had fewer DEGs at 4 wpi than at 12 wpi, and the majority of those with high numbers of DEGs were downregulated at 4 wpi and upregulated at 12 wpi. The functional annotation showed that the most enriched GO terms were immune-associated in both species; however, the terms associated with the innate immune response were predominantly enriched in the ducks, whereas the chickens had enrichment of both the innate and adaptive immune response. Immune-associated pathways were also enriched according to the KEGG pathway analysis in both species. Overall, the transcriptomic analysis of the duck and chicken brains showed that the main biological responses to ABBV-1 infection were immune-associated and corresponded with the levels of inflammation in the CNS.


Asunto(s)
Bornaviridae , Virus ARN , Animales , Patos , Pollos , Bornaviridae/genética , Perfilación de la Expresión Génica , Transcriptoma , Virus ARN/genética , Encéfalo , ARN/metabolismo
11.
Microorganisms ; 11(1)2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36677309

RESUMEN

Evaluating potential environmental and clinical impacts of industrial antibiotic use is critical in mitigating the spread of antimicrobial resistance. Using soil columns to simulate field application of swine or cattle manure and subsequent rain events, and a targeted qPCR-based approach, we tracked resistance genes from source manures and identified important differences in antimicrobial resistance gene transport and enrichment over time in the soil and water of artificially drained cropland. The source manures had distinct microbial community and resistance gene profiles, and these differences were also reflected in the soil columns after manure application. Antibiotic resistance genes (ARGs) were only significantly enriched in effluent samples following the first rain event (day 11) for both soil types compared to the control columns, illustrating the high background level of resistance present in the control soils chosen. For swine, the genes tetQ, tet(36), tet44, tetM, sul2 and ant(6)-ib persisted in the soil columns, whereas tetO, strB and sul1 persisted in effluent samples. Conversely, for cattle manure sul2 and strB persisted in both soil and effluent. The distinct temporal dynamics of ARG distribution between soil and effluent water for each manure type can be used to inform potential mitigation strategies in the future.

12.
Commun Biol ; 5(1): 216, 2022 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-35301418

RESUMEN

Effective monitoring of antibiotic resistance genes and their dissemination in environmental ecosystems has been hindered by the cost and efficiency of methods available for the task. We developed the Diversity of Antibiotic Resistance genes and Transfer Elements-Quantitative Monitoring (DARTE-QM), a method implementing TruSeq high-throughput sequencing to simultaneously sequence thousands of antibiotic resistant gene targets representing a full-spectrum of antibiotic resistance classes common to environmental systems. In this study, we demonstrated DARTE-QM by screening 662 antibiotic resistance genes within complex environmental samples originated from manure, soil, and livestock feces, in addition to a mock-community reference to assess sensitivity and specificity. DARTE-QM offers a new approach to studying antibiotic resistance in environmental microbiomes, showing advantages in efficiency and the ability to scale for many samples. This method provides a means of data acquisition that will alleviate some of the obstacles that many researchers in this area currently face.


Asunto(s)
Antibacterianos , Microbiota , Antibacterianos/farmacología , Farmacorresistencia Bacteriana/genética , Genes Bacterianos , Estiércol
13.
PLoS One ; 17(4): e0266829, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35395054

RESUMEN

Antimicrobial resistance (AMR) threatens the health of humans and animals and has repeatedly been detected in wild animal species across the world. This cross-sectional study integrates whole-genome sequence data from Escherichia coli isolates with demonstrated phenotypic resistance that originated from a previous longitudinal wildlife study in southern Ontario, as well as phenotypically resistant E. coli water isolates previously collected as part of a public health surveillance program. The objective of this work was to assess for evidence of possible transmission of antimicrobial resistance determinants between wild meso-mammals, swine manure pits, and environmental sources on a broad scale in the Grand River watershed, and at a local scale-for the subset of samples collected on both swine farms and conservation areas in the previous wildlife study. Logistic regression models were used to assess potential associations between sampling source, location type (swine farm vs. conservation area), and the occurrence of select resistance genes and predicted plasmids. In total, 200 isolates from the following sources were included: water (n = 20), wildlife (n = 73), swine manure pit (n = 31), soil (n = 73), and dumpsters (n = 3). Several genes and plasmid incompatibility types were significantly more likely to be identified on swine farms compared to conservation areas. Conversely, internationally distributed sequence types (e.g., ST131), extended-spectrum beta-lactamase- and AmpC-producing E. coli were isolated in lower prevalences (<10%) and were almost exclusively identified in water sources, or in raccoon and soil isolates obtained from conservation areas. Differences in the odds of detecting resistance genes and predicted plasmids among various sources and location types suggest different primary sources for individual AMR determinants, but, broadly, our findings suggest that raccoons, skunks and opossums in this region may be exposed to AMR pollution via water and agricultural sources, as well as anthropogenic sources in conservation areas.


Asunto(s)
Infecciones por Escherichia coli , Escherichia coli , Animales , Animales Salvajes/genética , Antibacterianos/farmacología , Estudios Transversales , Farmacorresistencia Bacteriana/genética , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/veterinaria , Granjas , Estiércol , Ontario/epidemiología , Plásmidos , Mapaches , Ríos , Suelo , Porcinos , Agua , beta-Lactamasas/genética
14.
Front Vet Sci ; 9: 840416, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35280127

RESUMEN

Non-typhoidal Salmonella infections represent a substantial burden of illness in humans, and the increasing prevalence of antimicrobial resistance among these infections is a growing concern. Using a combination of Salmonella isolate short-read whole-genome sequence data from select human cases, raccoons, livestock and environmental sources, and an epidemiological framework, our objective was to determine if there was evidence for potential transmission of Salmonella and associated antimicrobial resistance determinants between these different sources in the Grand River watershed in Ontario, Canada. Logistic regression models were used to assess the potential associations between source type and the presence of select resistance genes and plasmid incompatibility types. A total of 608 isolates were obtained from the following sources: humans (n = 58), raccoons (n = 92), livestock (n = 329), and environmental samples (n = 129). Resistance genes of public health importance, including bla CMY-2, were identified in humans, livestock, and environmental sources, but not in raccoons. Most resistance genes analyzed were significantly more likely to be identified in livestock and/or human isolates than in raccoon isolates. Based on a 3,002-loci core genome multi-locus sequence typing (cgMLST) scheme, human Salmonella isolates were often more similar to isolates from livestock and environmental sources, than with those from raccoons. Rare instances of serovars S. Heidelberg and S. Enteritidis in raccoons likely represent incidental infections and highlight possible acquisition and dissemination of predominantly poultry-associated Salmonella by raccoons within these ecosystems. Raccoon-predominant serovars were either not identified among human isolates (S. Agona, S. Thompson) or differed by more than 350 cgMLST loci (S. Newport). Collectively, our findings suggest that the rural population of raccoons on swine farms in the Grand River watershed are unlikely to be major contributors to antimicrobial resistant human Salmonella cases in this region.

15.
PLoS Genet ; 4(5): e1000067, 2008 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-18464914

RESUMEN

Dihydropyridines (DHPs) are L-type calcium channel (Ca(v)1) blockers prescribed to treat several diseases including hypertension. Ca(v)1 channels normally exist in three states: a resting closed state, an open state that is triggered by membrane depolarization, followed by a non-conducting inactivated state that is triggered by the influx of calcium ions, and a rapid change in voltage. DHP binding is thought to alter the conformation of the channel, possibly by engaging a mechanism similar to voltage dependent inactivation, and locking a calcium ion in the pore, thereby blocking channel conductance. As a Ca(v)1 channel crystal structure is lacking, the current model of DHP action has largely been achieved by investigating the role of candidate Ca(v)1 residues in mediating DHP-sensitivity. To better understand DHP-block and identify additional Ca(v)1 residues important for DHP-sensitivity, we screened 440,000 randomly mutated Caenorhabditis elegans genomes for worms resistant to DHP-induced growth defects. We identified 30 missense mutations in the worm Ca(v)1 pore-forming (alpha(1)) subunit, including eleven in conserved residues known to be necessary for DHP-binding. The remaining polymorphisms are in eight conserved residues not previously associated with DHP-sensitivity. Intriguingly, all of the worm mutants that we analyzed phenotypically exhibited increased channel activity. We also created orthologous mutations in the rat alpha(1C) subunit and examined the DHP-block of current through the mutant channels in culture. Six of the seven mutant channels examined either decreased the DHP-sensitivity of the channel and/or exhibited significant residual current at DHP concentrations sufficient to block wild-type channels. Our results further support the idea that DHP-block is intimately associated with voltage dependent inactivation and underscores the utility of C. elegans as a screening tool to identify residues important for DHP interaction with mammalian Ca(v)1 channels.


Asunto(s)
Caenorhabditis elegans/efectos de los fármacos , Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio Tipo L/metabolismo , Dihidropiridinas/farmacología , Resistencia a Medicamentos , Secuencia de Aminoácidos , Animales , Caenorhabditis elegans/genética , Caenorhabditis elegans/crecimiento & desarrollo , Caenorhabditis elegans/fisiología , Canales de Calcio Tipo L/química , Canales de Calcio Tipo L/genética , Línea Celular , Secuencia Conservada , Dihidropiridinas/metabolismo , Evaluación Preclínica de Medicamentos , Electrofisiología , Modelos Animales , Datos de Secuencia Molecular , Mutación Missense , Polimorfismo Genético , Ratas , Alineación de Secuencia
16.
Front Vet Sci ; 8: 742345, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34796225

RESUMEN

Streptococcus suis is ubiquitous in swine, and yet, only a small percentage of pigs become clinically ill. The objective of this study was to describe the distribution of serotypes, virulence-associated factor (VAF), and antimicrobial resistance (AMR) genes in S. suis isolates recovered from systemic (blood, meninges, spleen, and lymph node) and non-systemic (tonsil, nasal cavities, ileum, and rectum) sites of sick and healthy pigs using whole-genome sequencing. In total, 273 S. suis isolates recovered from 112 pigs (47 isolates from systemic and 136 from non-systemic sites of 65 sick pigs; 90 isolates from non-systemic sites of 47 healthy pigs) on 17 Ontario farms were subjected to whole-genome sequencing. Using in silico typing, 21 serotypes were identified with serotypes 9 (13.9%) and 2 (8.4%) as the most frequent serotypes, whereas 53 (19.4%) isolates remained untypable. The relative frequency of VAF genes in isolates from systemic (Kruskal-Wallis, p < 0.001) and non-systemic (Kruskal-Wallis, p < 0.001) sites in sick pigs was higher compared with isolates from non-systemic sites in healthy pigs. Although many VAF genes were abundant in all isolates, three genes, including dltA [Fisher's test (FT), p < 0.001], luxS (FT, p = 0.01), and troA (FT, p = 0.02), were more prevalent in isolates recovered from systemic sites compared with non-systemic sites of pigs. Among the isolates, 98% had at least one AMR gene, and 79% had genes associated with at least four drug classes. The most frequently detected AMR genes were tetO conferring resistance to tetracycline and ermB conferring resistance to macrolide, lincosamide, and streptogramin. The wide distribution of VAFs genes in S. suis isolates in this study suggests that other host and environmental factors may contribute to S. suis disease development.

17.
Pharmaceuticals (Basel) ; 14(3)2021 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-33670836

RESUMEN

Extended overuse and misuse of antibiotics and other antibacterial agents has resulted in an antimicrobial resistance crisis. Bacteriophages, viruses that infect bacteria, have emerged as a legitimate alternative antibacterial agent with a wide scope of applications which continue to be discovered and refined. However, the potential of some bacteriophages to aid in the acquisition, maintenance, and dissemination of negatively associated bacterial genes, including resistance and virulence genes, through transduction is of concern and requires deeper understanding in order to be properly addressed. In particular, their ability to interact with mobile genetic elements such as plasmids, genomic islands, and integrative conjugative elements (ICEs) enables bacteriophages to contribute greatly to bacterial evolution. Nonetheless, bacteriophages have the potential to be used as therapeutic and biocontrol agents within medical, agricultural, and food processing settings, against bacteria in both planktonic and biofilm environments. Additionally, bacteriophages have been deployed in developing rapid, sensitive, and specific biosensors for various bacterial targets. Intriguingly, their bioengineering capabilities show great promise in improving their adaptability and effectiveness as biocontrol and detection tools. This review aims to provide a balanced perspective on bacteriophages by outlining advantages, challenges, and future steps needed in order to boost their therapeutic and biocontrol potential, while also providing insight on their potential role in contributing to bacterial evolution and survival.

18.
Vet Microbiol ; 257: 109064, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33892450

RESUMEN

Streptococcus suis naturally colonizes the upper respiratory tract of pigs and can lead to severe disease conditions. Although there are several serotypes associated with disease, untypable isolates have also been observed. The objective of this study was to investigate the relatedness of untypable S. suis isolates detected in clinical cases and healthy pigs in Ontario, Canada, and their relation to typing serotypes. One hundred fifty-six isolates obtained from 33 cases and 26 farm-and-pen-matched control pigs were sequenced using Illumina HiSeq sequencing. Protein sequences of the capsular polysaccharide genes (cps) were identified and analyzed using a maximum likelihood tree. Among the 27 untypable isolates, 3 were from systemic sites of cases and 13 and 11 were from upper respiratory sites of cases and controls, respectively. One hundred fifty-six isolates were grouped into 17 distinct groups based on the cps gene tree. Isolates from these 17 distinct individual cps groups were distributed among a minimum of one farm and maximum of eight farms. Untypable isolates were detected in 12 of those groups and each cps group had untypable isolates present amongst multiple farms. Interestingly, the three systemic untypable isolates not only coexisted with other serotypes found in the same location of the same pigs but were also found among different cps groups. These isolates are of interest and warrant further investigation. Overall, a wide diversity of S. suis among untypable isolates was observed in this study.


Asunto(s)
Técnicas de Tipificación Bacteriana , Infecciones Estreptocócicas/veterinaria , Streptococcus suis/clasificación , Streptococcus suis/genética , Enfermedades de los Porcinos/microbiología , Animales , Granjas , Variación Genética , Ganado/microbiología , Filogenia , Serogrupo , Serotipificación , Infecciones Estreptocócicas/microbiología , Streptococcus suis/aislamiento & purificación , Porcinos
19.
PLoS One ; 16(11): e0260234, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34793571

RESUMEN

To better understand the contribution of wildlife to the dissemination of Salmonella and antimicrobial resistance in Salmonella and Escherichia coli, we examined whole-genome sequence data from Salmonella and E. coli isolates collected from raccoons (Procyon lotor) and environmental sources on farms in southern Ontario. All Salmonella and phenotypically resistant E. coli collected from raccoons, soil, and manure pits on five swine farms as part of a previous study were included. We assessed for evidence of potential transmission of these organisms between different sources and farms utilizing a combination of population structure assessments (using core-genome multi-locus sequence typing), direct comparisons of multi-drug resistant isolates, and epidemiological modeling of antimicrobial resistance (AMR) genes and plasmid incompatibility (Inc) types. Univariable logistic regression models were fit to assess the impact of source type, farm location, and sampling year on the occurrence of select resistance genes and Inc types. A total of 159 Salmonella and 96 resistant E. coli isolates were included. A diversity of Salmonella serovars and sequence types were identified, and, in some cases, we found similar or identical Salmonella isolates and resistance genes between raccoons, soil, and swine manure pits. Certain Inc types and resistance genes associated with source type were consistently more likely to be identified in isolates from raccoons than swine manure pits, suggesting that manure pits are not likely a primary source of those particular resistance determinants for raccoons. Overall, our data suggest that transmission of Salmonella and AMR determinants between raccoons and swine manure pits is uncommon, but soil-raccoon transmission appears to be occurring frequently. More comprehensive sampling of farms, and assessment of farms with other livestock species, as well as additional environmental sources (e.g., rivers) may help to further elucidate the movement of resistance genes between these various sources.


Asunto(s)
Farmacorresistencia Bacteriana/genética , Infecciones por Escherichia coli/epidemiología , Escherichia coli/genética , Estiércol/microbiología , Mapaches/microbiología , Infecciones por Salmonella/epidemiología , Salmonella/genética , Animales , Animales Salvajes/microbiología , Antibacterianos/farmacología , Pruebas Diagnósticas de Rutina/métodos , Escherichia coli/efectos de los fármacos , Infecciones por Escherichia coli/microbiología , Ganado/microbiología , Tipificación de Secuencias Multilocus/métodos , Ontario , Plásmidos/genética , Salmonella/efectos de los fármacos , Infecciones por Salmonella/microbiología , Suelo , Porcinos/microbiología , Secuenciación Completa del Genoma/métodos
20.
Microbiol Resour Announc ; 9(1)2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31896652

RESUMEN

Campylobacter jejuni is the main cause of bacterial foodborne disease in humans, who are exposed mostly by consumption of contaminated poultry products. C. jejuni strain NADC 20827 was isolated from the feces of turkeys naturally colonized with Campylobacter spp. We present the complete annotated genome and plasmid sequences of strain NADC 20827.

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