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1.
Br J Nurs ; 33(5): S4-S10, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38446520

RESUMEN

BACKGROUND: Cancer-related pain is a complex multidimensional experience that affects all aspects of life. To support those impacted by cancer-related pain it is essential that health professionals have adequate knowledge in its assessment and management. AIMS: To explore the knowledge of health professionals regarding cancer-related pain. METHODS: A scoping review methodology was used to systematically search the literature published between 2010 and 2020. Databases CINAHL, Medline and PsycINFO were searched using terms 'cancer pain', 'healthcare professional', 'knowledge', 'attitudes' and 'barriers'. FINDINGS: The search identified 38 articles. They focused on nursing knowledge with minimal involvement of allied health professionals. Knowledge levels were variable with the majority demonstrating poor knowledge. Common knowledge gaps included around fear of addiction, principles of cancer-related pain assessment and management, and interventional techniques. CONCLUSION: Knowledge of cancer-related pain is variable with several knowledge gaps. More work is needed to ensure health professionals have adequate knowledge regarding the complexity of cancer-related pain.


Asunto(s)
Dolor en Cáncer , Neoplasias , Humanos , Dolor en Cáncer/terapia , Neoplasias/complicaciones , Personal de Salud , Técnicos Medios en Salud , Bases de Datos Factuales
2.
Curr Osteoporos Rep ; 22(1): 105-114, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38198034

RESUMEN

PURPOSE OF REVIEW: The formation of a pre-metastatic niche (PMN), in which primary cancer cells prime the distant site to be favorable to their engraftment and survival, may help explain the strong osteotropism observed in multiple cancers, such as breast and prostate. PMN formation, which includes extracellular matrix remodeling, increased angiogenesis and vascular permeability, enhanced bone marrow-derived cell recruitment and immune suppression, has mostly been described in soft tissues. In this review, we summarize current literature of PMN formation in bone. We also present evidence of a potential role for osteocytes to be the primary mediators of PMN development. RECENT FINDINGS: Osteocytes regulate the bone microenvironment in myriad ways beyond canonical bone tissue remodeling, including changes that contribute to PMN formation. Perilacunar tissue remodeling, which has been observed in both bone and non-bone metastatic cancers, is a potential mechanism by which osteocyte-cancer cell signaling stimulates changes to the bone microenvironment. Osteocytes also protect against endothelial permeability, including that induced by cancer cells, in a loading-mediated process. Finally, osteocytes are potent regulators of cells within the bone marrow, including progenitors and immune cells, and might be involved in this aspect of PMN formation. Osteocytes should be examined for their role in PMN formation.


Asunto(s)
Neoplasias , Osteocitos , Masculino , Humanos , Osteocitos/patología , Remodelación Ósea , Neoplasias/patología , Huesos , Transducción de Señal , Microambiente Tumoral
3.
Proc Natl Acad Sci U S A ; 120(48): e2309306120, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-37988471

RESUMEN

RNA-DNA hybrids are epigenetic features of all genomes that intersect with many processes, including transcription, telomere homeostasis, and centromere function. Increasing evidence suggests that RNA-DNA hybrids can provide two conflicting roles in the maintenance and transmission of genomes: They can be the triggers of DNA damage, leading to genome change, or can aid the DNA repair processes needed to respond to DNA lesions. Evasion of host immunity by African trypanosomes, such as Trypanosoma brucei, relies on targeted recombination of silent Variant Surface Glycoprotein (VSG) genes into a specialized telomeric locus that directs transcription of just one VSG from thousands. How such VSG recombination is targeted and initiated is unclear. Here, we show that a key enzyme of T. brucei homologous recombination, RAD51, interacts with RNA-DNA hybrids. In addition, we show that RNA-DNA hybrids display a genome-wide colocalization with DNA breaks and that this relationship is impaired by mutation of RAD51. Finally, we show that RAD51 acts to repair highly abundant, localised DNA breaks at the single transcribed VSG and that mutation of RAD51 alters RNA-DNA hybrid abundance at 70 bp repeats both around the transcribed VSG and across the silent VSG archive. This work reveals a widespread, generalised role for RNA-DNA hybrids in directing RAD51 activity during recombination and uncovers a specialised application of this interplay during targeted DNA break repair needed for the critical T. brucei immune evasion reaction of antigenic variation.


Asunto(s)
Trypanosoma brucei brucei , Estructuras R-Loop , Variación Antigénica/genética , Roturas del ADN , ADN , ARN , Glicoproteínas Variantes de Superficie de Trypanosoma/genética
4.
Nucleic Acids Res ; 51(20): 11123-11141, 2023 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-37843098

RESUMEN

RNA-DNA hybrids are epigenetic features of genomes that provide a diverse and growing range of activities. Understanding of these functions has been informed by characterising the proteins that interact with the hybrids, but all such analyses have so far focused on mammals, meaning it is unclear if a similar spectrum of RNA-DNA hybrid interactors is found in other eukaryotes. The African trypanosome is a single-cell eukaryotic parasite of the Discoba grouping and displays substantial divergence in several aspects of core biology from its mammalian host. Here, we show that DNA-RNA hybrid immunoprecipitation coupled with mass spectrometry recovers 602 putative interactors in T. brucei mammal- and insect-infective cells, some providing activities also found in mammals and some lineage-specific. We demonstrate that loss of three factors, two putative helicases and a RAD51 paralogue, alters T. brucei nuclear RNA-DNA hybrid and DNA damage levels. Moreover, loss of each factor affects the operation of the parasite immune survival mechanism of antigenic variation. Thus, our work reveals the broad range of activities contributed by RNA-DNA hybrids to T. brucei biology, including new functions in host immune evasion as well as activities likely fundamental to eukaryotic genome function.


Asunto(s)
Trypanosoma brucei brucei , Animales , Trypanosoma brucei brucei/metabolismo , Evasión Inmune/genética , ARN/genética , Antígenos de Superficie , Variación Antigénica/genética , ADN/genética , Mamíferos/genética , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo
5.
Proc Natl Acad Sci U S A ; 120(42): e2306848120, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37824530

RESUMEN

The development of Trypanosoma brucei in its mammalian host is marked by a distinct morphological change as replicative "slender" forms differentiate into cell cycle arrested "stumpy" forms in a quorum-sensing-dependent manner. Although stumpy forms dominate chronic infections at the population level, the proportion of replicative parasites at the individual cell level and the irreversibility of arrest in the bloodstream are unclear. Here, we experimentally demonstrate that developmental cell cycle arrest is definitively irreversible in acute and chronic infections in mice. Furthermore, analysis of replicative capacity and single-cell transcriptome profiling reveal a temporal hierarchy, whereby cell cycle arrest and appearance of a reversible stumpy-like transcriptome precede irreversible commitment and morphological change. Unexpectedly, we show that proliferating parasites are exceptionally scarce in the blood after infections are established. This challenges the ability of bloodstream trypanosomes to sustain infection by proliferation or antigenic variation, these parasites instead being overwhelmingly adapted for transmission.


Asunto(s)
Trypanosoma brucei brucei , Trypanosoma , Humanos , Ratones , Animales , Infección Persistente , Trypanosoma brucei brucei/metabolismo , Mamíferos , Perfilación de la Expresión Génica
6.
Elife ; 122023 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-37166108

RESUMEN

African trypanosomes proliferate as bloodstream forms (BSFs) and procyclic forms in the mammal and tsetse fly midgut, respectively. This allows them to colonise the host environment upon infection and ensure life cycle progression. Yet, understanding of the mechanisms that regulate and drive the cell replication cycle of these forms is limited. Using single-cell transcriptomics on unsynchronised cell populations, we have obtained high resolution cell cycle regulated (CCR) transcriptomes of both procyclic and slender BSF Trypanosoma brucei without prior cell sorting or synchronisation. Additionally, we describe an efficient freeze-thawing protocol that allows single-cell transcriptomic analysis of cryopreserved T. brucei. Computational reconstruction of the cell cycle using periodic pseudotime inference allowed the dynamic expression patterns of cycling genes to be profiled for both life cycle forms. Comparative analyses identify a core cycling transcriptome highly conserved between forms, as well as several genes where transcript levels dynamics are form specific. Comparing transcript expression patterns with protein abundance revealed that the majority of genes with periodic cycling transcript and protein levels exhibit a relative delay between peak transcript and protein expression. This work reveals novel detail of the CCR transcriptomes of both forms, which are available for further interrogation via an interactive webtool.


Asunto(s)
Trypanosoma , Trypanosoma/citología , Trypanosoma/crecimiento & desarrollo , Trypanosoma/metabolismo , Análisis de Expresión Génica de una Sola Célula , Criopreservación , ARN Protozoario/análisis , Proteínas Protozoarias/análisis
7.
Neurooncol Pract ; 10(1): 79-88, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36654773

RESUMEN

Background: Glioblastoma (GBM) is a devastating form of brain cancer, with a short life expectancy. In addition to this poor prognosis, people with GBM often experience symptoms that may have a profound impact on their subjective well-being (SWB). The aim of this study was to investigate the lived experiences and perceptions of people with GBM regarding their SWB. Methods: The study adopted a longitudinal, hermeneutical phenomenological approach. Twenty-seven interviews were conducted with 15 patients over a period of two years. Most participants were interviewed twice on a face-to-face basis (during combined chemotherapy and radiotherapy, and again during adjuvant chemotherapy). The hermeneutic circle was used to guide data analysis. Results: Data analysis identified four key themes that depicted the lived experiences and perceptions of SWB of people with GBM. "Experience of the disease" focuses on the impact of diagnosis, symptoms and side effects. "Daily life" relates to daily activities, family roles, work and social lives. "Coping" includes the importance of normality and goal-setting. "Experiences of care" focuses on the impact of the treatment schedule, experiences of care and impressions of the monitoring of QoL. Conclusion: SWB is affected by a variety of factors throughout the GBM disease and treatment journey. The findings of this study suggest that healthcare professionals can enhance the SWB of people with GBM by providing personalized care that supports people to set themselves goals for the future and retain a degree of normality wherever possible.

8.
Cancers (Basel) ; 14(20)2022 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-36291807

RESUMEN

Oesophago-gastric cancer is difficult to diagnose in the early stages given its typical non-specific initial manifestation. We hypothesise that machine learning can improve upon the diagnostic performance of current primary care risk-assessment tools by using advanced analytical techniques to exploit the wealth of evidence available in the electronic health record. We used a primary care electronic health record dataset derived from the UK General Practice Research Database (7471 cases; 32,877 controls) and developed five probabilistic machine learning classifiers: Support Vector Machine, Random Forest, Logistic Regression, Naïve Bayes, and Extreme Gradient Boosted Decision Trees. Features included basic demographics, symptoms, and lab test results. The Logistic Regression, Support Vector Machine, and Extreme Gradient Boosted Decision Tree models achieved the highest performance in terms of accuracy and AUROC (0.89 accuracy, 0.87 AUROC), outperforming a current UK oesophago-gastric cancer risk-assessment tool (ogRAT). Machine learning also identified more cancer patients than the ogRAT: 11.0% more with little to no effect on false positives, or up to 25.0% more with a slight increase in false positives (for Logistic Regression, results threshold-dependent). Feature contribution estimates and individual prediction explanations indicated clinical relevance. We conclude that machine learning could improve primary care cancer risk-assessment tools, potentially helping clinicians to identify additional cancer cases earlier. This could, in turn, improve survival outcomes.

9.
Curr Opin Microbiol ; 70: 102209, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36215868

RESUMEN

Survival of the African trypanosome within its mammalian hosts, and hence transmission between hosts, relies upon antigenic variation, where stochastic changes in the composition of their protective variant-surface glycoprotein (VSG) coat thwart effective removal of the pathogen by adaptive immunity. Antigenic variation has evolved remarkable mechanistic complexity in Trypanosoma brucei, with switching of the VSG coat executed by either transcriptional or recombination reactions. In the former, a single T. brucei cell selectively transcribes one telomeric VSG transcription site, termed the expression site (ES), from a pool of around 15. Silencing of the active ES and activation of one previously silent ES can lead to a co-ordinated VSG coat switch. Outside the ESs, the T. brucei genome contains an enormous archive of silent VSG genes and pseudogenes, which can be recombined into the ES to execute a coat switch. Most such recombination involves gene conversion, including copying of a complete VSG and more complex reactions where novel 'mosaic' VSGs are formed as patchworks of sequences from several silent (pseudo)genes. Understanding of the cellular machinery that directs transcriptional and recombination VSG switching is growing rapidly and the emerging picture is of the use of proteins, complexes and pathways that are not limited to trypanosomes, but are shared across the wider grouping of kinetoplastids and beyond, suggesting co-option of widely used, core cellular reactions. We will review what is known about the machinery of antigenic variation and discuss if there remains the possibility of trypanosome adaptations, or even trypanosome-specific machineries, that might offer opportunities to impair this crucial parasite-survival process.


Asunto(s)
Trypanosoma brucei brucei , Trypanosoma , Animales , Glicoproteínas Variantes de Superficie de Trypanosoma/genética , Variación Antigénica/genética , Trypanosoma/genética , Trypanosoma brucei brucei/genética , Genoma , Mamíferos/genética
10.
Transl Anim Sci ; 6(3): txac120, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36172462

RESUMEN

The objectives of these experiments were to determine the relationship between maintenance requirements and energy partitioned to maternal tissue or milk production in limit-fed Angus cows and to determine the relationship between retained energy during the lactation period to dry-period voluntary forage intake (VDMI). Twenty-four mature fall-calving Angus cows were used in a 79-d study during late lactation to establish daily metabolizable energy required for maintenance (MEm). Cows were individually fed daily a mixed diet (2.62 Mcal MEl/kg, 18.2% crude protein) to meet energy and protein requirements of 505 kg beef cows producing 8.2 kg milk daily. If cow BW changed by ±9 kg from initial BW, daily feed intake was adjusted to slow BW loss or reduce BW gain. Milk yield and composition were determined on 3 occasions throughout the study. Maintenance was computed as metabolizable energy intake minus retained energy assigned to average daily maternal tissue energy change, average daily milk energy yield, and average daily energy required for pregnancy. After calves were weaned, cows were fed a low-quality grass hay diet (8.2% crude protein, 65% NDF) and VDMI was measured for 21 days. Lactation maintenance energy was 83% the default value recommended by NASEM (2016. Nutrient Requirements of Beef Cattle: Eighth Revised Edition.) for lactating Angus cows. Increasing lactation-period retained energy (decreasing BW loss and increasing milk energy yield) was associated with lower maintenance energy requirements (P < 0.01; R 2 = 0.92). Increased residual daily gain during lactation was associated with lower lactation maintenance energy requirements (P = 0.05; R 2 = 0.17). Post-weaning VDMI was not related to late-lactation milk energy production, although sensitive to lactation period BCS and BW loss. These results contradict previous reports, suggesting that maintenance requirements increase with increasing milk yield.

11.
Nat Commun ; 13(1): 5752, 2022 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-36180478

RESUMEN

Human African trypanosomiasis, or sleeping sickness, is caused by the protozoan parasite Trypanosoma brucei and induces profound reactivity of glial cells and neuroinflammation when the parasites colonise the central nervous system. However, the transcriptional and functional responses of the brain to chronic T. brucei infection remain poorly understood. By integrating single cell and spatial transcriptomics of the mouse brain, we identify that glial responses triggered by infection are readily detected in the proximity to the circumventricular organs, including the lateral and 3rd ventricle. This coincides with the spatial localisation of both slender and stumpy forms of T. brucei. Furthermore, in silico predictions and functional validations led us to identify a previously unknown crosstalk between homeostatic microglia and Cd138+ plasma cells mediated by IL-10 and B cell activating factor (BAFF) signalling. This study provides important insights and resources to improve understanding of the molecular and cellular responses in the brain during infection with African trypanosomes.


Asunto(s)
Parásitos , Trypanosoma brucei brucei , Tripanosomiasis Africana , Animales , Factor Activador de Células B , Encéfalo/parasitología , Humanos , Interleucina-10 , Ratones , Microglía , Células Plasmáticas , Transcriptoma , Trypanosoma brucei brucei/genética , Tripanosomiasis Africana/parasitología
12.
Front Cell Infect Microbiol ; 12: 900878, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35734575

RESUMEN

In the age of big data an important question is how to ensure we make the most out of the resources we generate. In this review, we discuss the major methods used in Apicomplexan and Kinetoplastid research to produce big datasets and advance our understanding of Plasmodium, Toxoplasma, Cryptosporidium, Trypanosoma and Leishmania biology. We debate the benefits and limitations of the current technologies, and propose future advancements that may be key to improving our use of these techniques. Finally, we consider the difficulties the field faces when trying to make the most of the abundance of data that has already been, and will continue to be, generated.


Asunto(s)
Criptosporidiosis , Cryptosporidium , Plasmodium , Toxoplasma , Macrodatos , Humanos
13.
Nat Commun ; 12(1): 5268, 2021 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-34489460

RESUMEN

Developmental steps in the trypanosome life-cycle involve transition between replicative and non-replicative forms specialised for survival in, and transmission between, mammalian and tsetse fly hosts. Here, using oligopeptide-induced differentiation in vitro, we model the progressive development of replicative 'slender' to transmissible 'stumpy' bloodstream form Trypanosoma brucei and capture the transcriptomes of 8,599 parasites using single cell transcriptomics (scRNA-seq). Using this framework, we detail the relative order of biological events during asynchronous development, profile dynamic gene expression patterns and identify putative regulators. We additionally map the cell cycle of proliferating parasites and position stumpy cell-cycle exit at early G1 before progression to a distinct G0 state. A null mutant for one transiently elevated developmental regulator, ZC3H20 is further analysed by scRNA-seq, identifying its point of failure in the developmental atlas. This approach provides a paradigm for the dissection of differentiation events in parasites, relevant to diverse transitions in pathogen biology.


Asunto(s)
Proteínas Protozoarias/genética , Trypanosoma brucei brucei/citología , Trypanosoma brucei brucei/fisiología , Animales , Ciclo Celular/genética , Ciclo Celular/fisiología , Regulación de la Expresión Génica , Mutación , Percepción de Quorum , Análisis de Secuencia de ARN/métodos , Análisis de la Célula Individual , Trypanosoma brucei brucei/genética
14.
Parasitology ; 148(10): 1223-1236, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33678213

RESUMEN

Kinetoplastid parasites are responsible for both human and animal diseases across the globe where they have a great impact on health and economic well-being. Many species and life cycle stages are difficult to study due to limitations in isolation and culture, as well as to their existence as heterogeneous populations in hosts and vectors. Single-cell transcriptomics (scRNA-seq) has the capacity to overcome many of these difficulties, and can be leveraged to disentangle heterogeneous populations, highlight genes crucial for propagation through the life cycle, and enable detailed analysis of host­parasite interactions. Here, we provide a review of studies that have applied scRNA-seq to protozoan parasites so far. In addition, we provide an overview of sample preparation and technology choice considerations when planning scRNA-seq experiments, as well as challenges faced when analysing the large amounts of data generated. Finally, we highlight areas of kinetoplastid research that could benefit from scRNA-seq technologies.


Asunto(s)
Perfilación de la Expresión Génica , Kinetoplastida/genética , Análisis de la Célula Individual , Interacciones Huésped-Parásitos , RNA-Seq
15.
Trends Genet ; 37(1): 21-34, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32993968

RESUMEN

The genomes of all organisms are read throughout their growth and development, generating new copies during cell division and encoding the cellular activities dictated by the genome's content. However, genomes are not invariant information stores but are purposefully altered in minor and major ways, adapting cellular behaviour and driving evolution. Kinetoplastids are eukaryotic microbes that display a wide range of such read-write genome activities, in many cases affecting critical aspects of their biology, such as host adaptation. Here we discuss the range of read-write genome changes found in two well-studied kinetoplastid parasites, Trypanosoma brucei and Leishmania, focusing on recent work that suggests such adaptive genome variation is linked to novel strategies the parasites use to replicate their unconventional genomes.


Asunto(s)
Replicación del ADN , ADN de Cinetoplasto/genética , Genoma de Protozoos , Kinetoplastida/genética , Leishmania/genética , Trypanosoma brucei brucei/genética , Animales
17.
Br J Pain ; 14(3): 195-205, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32922781

RESUMEN

In this article, we present a secondary analysis of a descriptive phenomenological study that we conducted in the United Kingdom exploring nurses' experiences of working with patients with substance dependence and pain. Our aim was to focus upon the ethical issues that emerged in the empirical data and so we used the Four Principles of Biomedical Ethics plus attention to scope to guide and inform our analysis. We present six key themes: trust, paternalism, coercion, failure to respect autonomy, advocacy and withholding. We discuss how these themes intersect with the four principles plus scope to illuminate practice and the ethical issues that emerge when managing this patient population's pain. We recommend that clinicians adopt a collaborative approach to managing pain for patients with substance dependence that they remain aware of the power differentials inherent within the clinical setting and ensure that communication and teamwork remain at the forefront of decisions. Clinicians need access to ethical guidance to inform their practice decisions and clinical ethics support services could provide one solution.

18.
Nucleic Acids Res ; 48(17): 9660-9680, 2020 09 25.
Artículo en Inglés | MEDLINE | ID: mdl-32890403

RESUMEN

Maintenance of genome integrity is critical to guarantee transfer of an intact genome from parent to offspring during cell division. DNA polymerases (Pols) provide roles in both replication of the genome and the repair of a wide range of lesions. Amongst replicative DNA Pols, translesion DNA Pols play a particular role: replication to bypass DNA damage. All cells express a range of translesion Pols, but little work has examined their function in parasites, including whether the enzymes might contribute to host-parasite interactions. Here, we describe a dual function of one putative translesion Pol in African trypanosomes, which we now name TbPolIE. Previously, we demonstrated that TbPolIE is associated with telomeric sequences and here we show that RNAi-mediated depletion of TbPolIE transcripts results in slowed growth, altered DNA content, changes in cell morphology, and increased sensitivity to DNA damaging agents. We also show that TbPolIE displays pronounced localization at the nuclear periphery, and that its depletion leads to chromosome segregation defects and increased levels of endogenous DNA damage. Finally, we demonstrate that TbPolIE depletion leads to deregulation of telomeric variant surface glycoprotein genes, linking the function of this putative translesion DNA polymerase to host immune evasion by antigenic variation.


Asunto(s)
Variación Antigénica , ADN Polimerasa Dirigida por ADN/metabolismo , Telómero/genética , Trypanosoma brucei brucei/genética , Línea Celular , Núcleo Celular/enzimología , Núcleo Celular/genética , Segregación Cromosómica , Replicación del ADN , ADN Polimerasa Dirigida por ADN/genética , Regulación de la Expresión Génica , Genoma de Protozoos , Humanos , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Interferencia de ARN , Telómero/metabolismo , Trypanosoma brucei brucei/metabolismo , Trypanosoma brucei brucei/patogenicidad , Glicoproteínas Variantes de Superficie de Trypanosoma/genética
19.
Methods Mol Biol ; 2116: 225-262, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32221924

RESUMEN

Understanding the rate and patterns of genome variation is becoming ever more amenable to whole-genome analysis through advances in DNA sequencing, which may, at least in some circumstances, have supplanted more localized analyses by cellular and genetic approaches. Whole-genome analyses can utilize both short- and long-read sequence technologies. Here we describe how sequence generated by these approaches has been used in trypanosomatids to examine DNA replication dynamics, the accumulation of modified histone H2A due to genome damage, and evaluation of genome variation, focusing on ploidy change.


Asunto(s)
Genoma de Protozoos/genética , Inestabilidad Genómica , Secuenciación de Nucleótidos de Alto Rendimiento , Leishmania major/genética , Análisis de Secuencia de ADN , Cromosomas/genética , Biología Computacional/métodos , Variaciones en el Número de Copia de ADN , ADN Protozoario/genética , Conjuntos de Datos como Asunto , Histonas/genética , Parasitología/métodos
20.
J Equine Vet Sci ; 82: 102770, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31732115

RESUMEN

Limited research exists regarding proximity of vehicles to "vulnerable road users" and effects of "conspicuity equipment". Previous studies stated over 60% of horse/rider combinations experience near-miss traffic collisions in any one year, whereas use of fluorescent/reflective (FR) equipment did not decrease occurrences. Similarly, research into vehicle proximity to bicycles reported no significance in cyclists wearing FR. This study undertook a similar field experiment using a horse/rider combination wearing different conspicuity equipment to test proximity distance. Two horses with similar height, age, base coat color, and temperament were ridden using four conspicuity measures 60 times each (n = 240) along a straight 0.8 km lane. Measures were chosen by random crossover with two selected for each separate trip. These were an FR "tabard", a novel black/white pattern (BW), flashing lights on a helmet (L), and control of mid-blue (C). A novel proximity meter was used on the saddle pommel and distance/approach either front or rear were logged into a voice recorder. Analysis reported a significant difference between all measures and proximities observed (P = .000). Mann-Whitney tests concluded significant differences in proximity in C versus L and BW (P = .000; P = .000), respectively. FR versus C showed no significant difference in proximity (P = .005). L versus BW reported no significant difference in proximity (W = 3640.0, P = .958). Results may suggest wearing conspicuity equipment of L or BW outperforms both C and FR. Further study is recommended to test these findings, and it is pertinent to still consider suggesting the use of FR equipment due to previous positive findings with other road users.


Asunto(s)
Accidentes de Tránsito , Animales , Color , Caballos , Reino Unido
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