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1.
Microb Genom ; 9(5)2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37227264

RESUMO

Bovine tuberculosis (bTB) is a costly, epidemiologically complex, multi-host, endemic disease. Lack of understanding of transmission dynamics may undermine eradication efforts. Pathogen whole-genome sequencing improves epidemiological inferences, providing a means to determine the relative importance of inter- and intra-species host transmission for disease persistence. We sequenced an exceptional data set of 619 Mycobacterium bovis isolates from badgers and cattle in a 100 km2 bTB 'hotspot' in Northern Ireland. Historical molecular subtyping data permitted the targeting of an endemic pathogen lineage, whose long-term persistence provided a unique opportunity to study disease transmission dynamics in unparalleled detail. Additionally, to assess whether badger population genetic structure was associated with the spatial distribution of pathogen genetic diversity, we microsatellite genotyped hair samples from 769 badgers trapped in this area. Birth death models and TransPhylo analyses indicated that cattle were likely driving the local epidemic, with transmission from cattle to badgers being more common than badger to cattle. Furthermore, the presence of significant badger population genetic structure in the landscape was not associated with the spatial distribution of M. bovis genetic diversity, suggesting that badger-to-badger transmission is not playing a major role in transmission dynamics. Our data were consistent with badgers playing a smaller role in transmission of M. bovis infection in this study site, compared to cattle. We hypothesize, however, that this minor role may still be important for persistence. Comparison to other areas suggests that M. bovis transmission dynamics are likely to be context dependent, with the role of wildlife being difficult to generalize.


Assuntos
Mustelidae , Mycobacterium bovis , Tuberculose Bovina , Animais , Bovinos , Mycobacterium bovis/genética , Mustelidae/microbiologia , Irlanda do Norte/epidemiologia , Tuberculose Bovina/microbiologia , Genômica
2.
R Soc Open Sci ; 7(4): 200288, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32431911

RESUMO

The colonization of Ireland by mammals has been the subject of extensive study using genetic methods and forms a central problem in understanding the phylogeography of European mammals after the Last Glacial Maximum. Ireland exhibits a depauperate mammal fauna relative to Great Britain and continental Europe, and a range of natural and anthropogenic processes have given rise to its modern fauna. Previous Europe-wide surveys of the European badger (Meles meles) have found conflicting microsatellite and mitochondrial DNA evidence in Irish populations, suggesting Irish badgers have arisen from admixture between human imported British and Scandinavian animals. The extent and history of contact between British and Irish badger populations remains unclear. We use comprehensive genetic data from Great Britain and Ireland to demonstrate that badgers in Ireland's northeastern and southeastern counties are genetically similar to contemporary British populations. Simulation analyses suggest this admixed population arose in Ireland 600-700 (CI 100-2600) years before present most likely through introduction of British badgers by people. These findings add to our knowledge of the complex colonization history of Ireland by mammals and the central role of humans in facilitating it.

3.
Ecol Evol ; 8(20): 10233-10246, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30397461

RESUMO

The population genetic structure of free-ranging species is expected to reflect landscape-level effects. Quantifying the role of these factors and their relative contribution often has important implications for wildlife management. The population genetics of the European badger (Meles meles) have received considerable attention, not least because the species acts as a potential wildlife reservoir for bovine tuberculosis (bTB) in Britain and Ireland. Herein, we detail the most comprehensive population and landscape genetic study of the badger in Ireland to date-comprised of 454 Irish badger samples, genotyped at 14 microsatellite loci. Bayesian and multivariate clustering methods demonstrated continuous clinal variation across the island, with potentially distinct differentiation observed in Northern Ireland. Landscape genetic analyses identified geographic distance and elevation as the primary drivers of genetic differentiation, in keeping with badgers exhibiting high levels of philopatry. Other factors hypothesized to affect gene flow, including earth worm habitat suitability, land cover type, and the River Shannon, had little to no detectable effect. By providing a more accurate picture of badger population structure and the factors effecting it, these data can guide current efforts to manage the species in Ireland and to better understand its role in bTB.

4.
Vet Microbiol ; 182: 131-4, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26711039

RESUMO

The increasing number of reports of livestock-associated meticillin-resistant Staphylococcus aureus (LA-MRSA) world-wide attests to the public health concern surrounding this pathogen in animal husbandry and in-contact humans. In Europe, LA-MRSA CC398 is predominant and generally regarded as being of low virulence for animals. Herein we report the recovery of a lineage of LA-MRSA, belonging to CC30, from three pigs in Northern Ireland and which encodes a marker of virulence (lukM and lukF-P83) restricted to animal-associated clones of S. aureus.


Assuntos
Proteínas de Bactérias/metabolismo , Staphylococcus aureus Resistente à Meticilina/metabolismo , Infecções Estafilocócicas/veterinária , Doenças dos Suínos/microbiologia , Animais , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Staphylococcus aureus Resistente à Meticilina/genética , Irlanda do Norte/epidemiologia , Filogenia , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Suínos , Doenças dos Suínos/epidemiologia
5.
Bioinspir Biomim ; 10(5): 056002, 2015 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-26292164

RESUMO

Most robotic applications that contain shape memory alloy (SMA) actuators use the SMA in a linear or spring shape. In contrast, a novel robotic finger was designed in this paper using SMA plates that were thermomechanically trained to take the shape of a flexed human finger when Joule heated. This flexor actuator was placed in parallel with an extensor actuator that was designed to straighten when Joule heated. Thus, alternately heating and cooling the flexor and extensor actuators caused the finger to flex and extend. Three different NiTi based SMA plates were evaluated for their ability to apply forces to a rigid and compliant object. The best of these three SMAs was able to apply a maximum fingertip force of 9.01N on average. A 3D CAD model of a human finger was used to create a solid model for the mold of the finger covering skin. Using a 3D printer, inner and outer molds were fabricated to house the actuators and a position sensor, which were assembled using a multi-stage casting process. Next, a nonlinear antagonistic controller was developed using an outer position control loop with two inner MOSFET current control loops. Sine and square wave tracking experiments demonstrated minimal errors within the operational bounds of the finger. The ability of the finger to recover from unexpected disturbances was also shown along with the frequency response up to 7 rad s(-1). The closed loop bandwidth of the system was 6.4 rad s(-1) when operated intermittently and 1.8 rad s(-1) when operated continuously.


Assuntos
Ligas/química , Biomimética/instrumentação , Dedos/fisiologia , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Robótica/instrumentação , Módulo de Elasticidade , Desenho de Equipamento , Análise de Falha de Equipamento , Temperatura Alta , Humanos , Estresse Mecânico , Transdutores
6.
BMC Genet ; 11: 5, 2010 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-20100323

RESUMO

BACKGROUND: Animal identification is pivotal in governmental agricultural policy, enabling the management of subsidy payments, movement of livestock, test scheduling and control of disease. Advances in bovine genomics have made it possible to utilise inherent genetic variability to uniquely identify individual animals by DNA profiling, much as has been achieved with humans over the past 20 years. A DNA profiling test based on bi-allelic single nucleotide polymorphism (SNP) markers would offer considerable advantages over current short tandem repeat (STR) based industry standard tests, in that it would be easier to analyse and interpret. In this study, a panel of 51 genome-wide SNPs were genotyped across panels of semen DNA from 6 common breeds for the purposes of ascertaining allelic frequency. For SNPs on the same chromosome, the extent of linkage disequilbrium was determined from genotype data by Expectation Maximization (EM) algorithm. Minimum probabilities of unique identification were determined for each breed panel. The usefulness of this SNP panel was ascertained by comparison to the current bovine STR Stockmarks II assay. A statistically representative random sampling of bovine animals from across Northern Ireland was assembled for the purposes of determining the population allele frequency for these STR loci and subsequently, the minimal probability of unique identification they conferred in sampled bovine animals from Northern Ireland. RESULTS: 6 SNPs exhibiting a minor allele frequency of less than 0.2 in more than 3 of the breed panels were excluded. 2 Further SNPs were found to reside in coding areas of the cattle genome and were excluded from the final panel. The remaining 43 SNPs exhibited genotype frequencies which were in Hardy Weinberg Equilibrium. SNPs on the same chromosome were observed to have no significant linkage disequilibrium/allelic association. Minimal probabilities of uniquely identifying individual animals from each of the breeds were obtained and were observed to be superior to those conferred by the industry standard STR assay. CONCLUSIONS: The 43 SNPs characterised herein may constitute a starting point for the development of a SNP based DNA identification test for European cattle.


Assuntos
Bovinos/genética , Genética Populacional , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA/métodos , Algoritmos , Animais , Frequência do Gene , Desequilíbrio de Ligação , Masculino , Irlanda do Norte , Sêmen/química
7.
Nurs Stand ; 8(21): 42, 1994 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-27666057

RESUMO

I'm afraid I did not find Jon Gould's clinical article, The impact of change on violent patients (February 2) helpful.

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