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1.
J Gen Virol ; 105(2)2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38329395

RESUMO

Infections with persistent or latent viruses alter host immune homeostasis and have potential to affect the outcome of concomitant acute viral infections such as influenza A virus (IAV). Gammaherpesviruses establish life-long infections and require an on-going immune response to control reactivation. We have used a murine model of co-infection to investigate the response to IAV infection in mice latently infected with the gammaherpesvirus MHV-68. Over the course of infection, latently infected BALB/c mice showed less weight loss, clinical signs, pulmonary cellular infiltration and expression of inflammatory mediators than naïve mice infected with IAV and had significantly more activated CD8+ T cells in the lungs. Four days after IAV infection, virus spread in the lungs of latently infected animals was significantly lower than in naïve animals. By 7 days after IAV infection latently infected lungs express elevated levels of cytokines and chemokines indicating they are primed to respond to the secondary infection. Investigation at an early time point showed that 24 h after IAV infection co-infected animals had higher expression of IFNß and Ddx58 (RIG-I) and a range of ISGs than mice infected with IAV alone suggesting that the type I IFN response plays a role in the protective effect. This effect was mouse strain dependent and did not occur in 129/Sv/Ev mice. These results offer insight into innate immune mechanisms that could be utilized to protect against IAV infection and highlight on-going and persistent viral infections as a significant factor impacting the severity of acute respiratory infections.


Assuntos
Coinfecção , Gammaherpesvirinae , Vírus da Influenza A , Influenza Humana , Interferon Tipo I , Animais , Camundongos , Humanos , Linfócitos T CD8-Positivos , Camundongos Endogâmicos BALB C
2.
Equine Vet J ; 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38301732

RESUMO

BACKGROUND: Equine grass sickness (EGS) is a frequently fatal multisystem neuropathy of equids. The aetiology is unknown; proposed causes include toxicoinfection with Clostridium botulinum and a mycotoxicosis. The effect of EGS on the organisation and structural integrity of the skeletal neuromuscular junction (NMJ), the target of botulinum neurotoxins (BoNTs), is unknown. OBJECTIVES: To compare the organisation and structural integrity of skeletal NMJs from EGS horses, control horses and one horse with a presumptive diagnosis of botulism. STUDY DESIGN: Blinded, retrospective case control. METHODS: NMJs in samples of diaphragm or intercostal muscle from six EGS horses, three control horses and one equine botulism case were compared using electron microscopy, morphometry and confocal light microscopy. RESULTS: A significantly higher percentage of EGS NMJs had abnormal morphology (EGS 72.2%, 95% CI 55.6-84.4; Controls 6.9%, 1.7-23.8; OR 35.1, 8.47-244.8; p < 0.001). EGS NMJs had a significantly lower mean volume fraction occupied by synaptic vesicles (SVs) (EGS 18.7%, 12.6-28.0; Controls 36.3%, 20.8-63.4; p = 0.024). EGS NMJs had evidence of accelerated SV exocytosis and SV depletion, accumulation of neurofilament-like material in terminal boutons and/or bouton degeneration. NMJs from the botulism horse had dense packing of SVs towards the presynaptic membrane active zone, consistent with BoNT intoxication, but had absence of the abnormalities identified in EGS NMJs. MAIN LIMITATIONS: Group sizes were limited by difficulties obtaining suitably processed samples. Ages of control and EGS horses differed. Botulism was diagnosed based on clinical and post mortem findings. CONCLUSIONS: EGS is associated with major changes in skeletal NMJ ultrastructure that are inconsistent with the effects of BoNTs. SV depletion may reflect increased exocytosis coupled with reduced repopulation of SVs via anterograde axonal transport and endocytosis, consistent with the action of an excitatory presynaptic toxin and/or neurotransmitter reuptake inhibitor. Skeletal NMJs represent a previously unrecognised target for the toxin that causes EGS.

3.
Anat Sci Educ ; 17(1): 102-113, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37529887

RESUMO

Limited research has been conducted on the spatial ability of veterinary students and how this is evaluated within anatomy assessments. This study describes the creation and evaluation of a split design multiple-choice question (MCQ) assessment (totaling 30 questions divided into 15 non-spatial MCQs and 15 spatial MCQs). Two cohorts were tested, one cohort received a 2D teaching method in the academic year 2014/15 (male = 15/108, female 93/108), and the second a 3D teaching method in the academic year 2015/16 (male 14/98, female 84/98). The evaluation of the MCQ demonstrated strong reliability (KR-20 = 0.71 2D and 0.63 3D) meaning the MCQ consistently tests the same construct. Factor analysis of the MCQ provides evidence of validity of the split design of the assessment (RR = 1.11, p = 0.013). Neither cohort outperformed on the non-spatial questions (p > 0.05), however, the 3D cohort performed statistically significantly higher on the spatial questions (p = 0.013). The results of this research support the design of a new anatomy assessment aimed at testing both anatomy knowledge and the problem-solving aspects of anatomical spatial ability. Furthermore, a 3D teaching method was shown to increase students' performance on anatomy questions testing spatial ability.


Assuntos
Anatomia , Educação de Graduação em Medicina , Estudantes de Medicina , Humanos , Masculino , Feminino , Avaliação Educacional/métodos , Reprodutibilidade dos Testes , Anatomia/educação , Resolução de Problemas , Educação de Graduação em Medicina/métodos
4.
J Vet Intern Med ; 37(6): 2188-2199, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37815154

RESUMO

BACKGROUND: Angiotensin-converting enzyme inhibitors (ACEi) are a recommended treatment for glomerular proteinuria. Frequency of response to ACEi and the association of achieving proposed urine protein-to-creatinine ratio (UPC) targets on survival is unknown. OBJECTIVES: To determine response rates to ACEi therapy and whether a positive response is associated with improved survival. ANIMALS: Eighty-five dogs with proteinuria (UPC > 2.0). METHODS: Retrospective study including dogs (UPC > 2.0) prescribed an ACEi for treatment of proteinuria. Baseline creatinine, albumin, cholesterol, UPC, and systolic blood pressure were recorded, and cases reviewed to track UPC. Treatment response was defined as achieving a UPC of <0.5 or reduction of ≥50% from baseline within 3 months. Outcome data were collected to determine overall and 12-month survival. RESULTS: Thirty-five (41%) dogs responded to ACEi treatment. Treatment response was statistically associated with both median survival time (664 days [95% confidence interval (CI): 459-869] for responders compared to 177 [95% CI: 131-223] for non-responders) and 12-month survival (79% responders alive compared to 28% non-responders). Baseline azotemia or hypoalbuminemia were also associated with a worse prognosis, with odds ratios of death at 12 months of 5.34 (CI: 1.85-17.32) and 4.51 (CI: 1.66-13.14), respectively. In the 25 dogs with normal baseline creatinine and albumin, response to treatment was associated with 12-month survival (92% responders alive compared to 54% non-responders, P = .04). CONCLUSIONS AND CLINICAL IMPORTANCE: When the UPC is >2.0, achieving recommended UPC targets within 3 months appears to be associated with a significant survival benefit. Response to treatment is still associated with survival benefit in dogs with less severe disease (no azotemia or hypoalbuminemia).


Assuntos
Azotemia , Doenças do Cão , Hipoalbuminemia , Animais , Cães , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Creatinina , Hipoalbuminemia/tratamento farmacológico , Hipoalbuminemia/veterinária , Estudos Retrospectivos , Proteinúria/tratamento farmacológico , Proteinúria/veterinária , Albuminas , Azotemia/tratamento farmacológico , Azotemia/veterinária , Doenças do Cão/tratamento farmacológico
5.
Pathogens ; 12(6)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37375479

RESUMO

Mycobacterium bovis, the causative agent of bovine tuberculosis (bTB), is a globally prevalent pathogen with significant animal welfare, economic and public health impacts. In the UK, the control of bTB relies on detection via tuberculin skin tests with ancillary interferon gamma (IFN-γ) release assays, followed by culling infected animals. Vaccination with Bacille Calmette-Guérin (BCG) could be an important element of bTB control, and a number of studies have demonstrated its protective efficacy, particularly when young calves are vaccinated. Here, we compared immune responses and the protective efficacy of BCG in calves vaccinated within the first day of life and at three weeks of age. Significant protection from M. bovis infection was observed in BCG-vaccinated calves compared to non-vaccinated, age-matched controls. No significant differences were shown between calves vaccinated at one day and at three weeks of age when assessing the protective efficacy of BCG (measured as a reduction in lesions and bacterial burden). Antigen-specific IFN-γ levels were similar between the BCG-vaccinated groups, but significantly different from the non-vaccinated control animals. Antigen-specific IFN-γ expression post-BCG vaccination was correlated significantly with protection from M. bovis infection, whereas IFN-γ levels post-challenge correlated with pathology and bacterial burden. These results indicate that early-life vaccination with BCG could have a significant impact on M. bovis infection and, therefore, bTB incidence, and they demonstrate that age, at least within the first month of life, does not significantly impact the protective effect of vaccination.

6.
Sci Rep ; 13(1): 1875, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36726018

RESUMO

Bovine tuberculosis is a contagious bacterial disease of worldwide economic, zoonotic and welfare importance caused mainly by Mycobacterium bovis infection. Current regulatory diagnostic methods lack sensitivity and require improvement. We have developed a multiplex serological test for bovine tuberculosis and here we provide an estimate of the diagnostic accuracy of the test in cattle. Positive and negative reference serum samples were obtained from animals from Europe and the United States of America. The diagnostic specificity estimate was 98.4% and 99.7% using high sensitivity and high specificity settings of the test respectively. Tuberculin boosting did not affect the overall specificity estimate. The diagnostic sensitivity in samples from Mycobacterium bovis culture positive animals following tuberculin boosting was 93.9%.The relative sensitivity following boosting in tuberculin test positive, lesion positive animals and interferon gamma test positive, lesion positive animals was 97.2% and 96.9% respectively. In tuberculin test negative, lesion positive animals and in interferon gamma test negative, lesion positive animals, the relative sensitivity following tuberculin boosting was 88.2% and 83.6% respectively. The results show that the test has high diagnostic sensitivity and specificity and can detect infected animals that are missed by tuberculin and interferon gamma testing.


Assuntos
Mycobacterium bovis , Tuberculose Bovina , Animais , Bovinos , Tuberculina , Interferon gama , Teste Tuberculínico/veterinária , Teste Tuberculínico/métodos , Sensibilidade e Especificidade
7.
Zoo Biol ; 42(3): 416-428, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36683292

RESUMO

Beliefs influence the intentions of people to behave in certain ways towards animals. This study presents survey responses from 237 people working in zoos in China and Europe and describes their demographic characteristics. It explores their beliefs about zoo animal behaviour, welfare and ethical issues, and zoo practices, using a survey methodology. These beliefs may be influenced by individual demographic or cultural factors such as age, gender and region of employment, as well as experiential or situative 'norms' within the work environment. Beliefs were significantly influenced by the region of employment with Chinese respondents beliefs being significantly different to beliefs from respondents in the United Kingdom or the rest of Europe. Hierarchical cluster analysis of the survey generated clusters of people from both regions who indicated positive beliefs about zoo animal welfare as well as clu sters indicating a lack of understanding of some zoo animal welfare issues. In addition, a cluster suggesting cognitive dissonance between beliefs about animals welfare and zoo practices was generated from Chinese responses. Factor analysis identified that prioritisation of in-situ conservation within good animal welfare was a key feature in Chinese respondents, whereas European beliefs prioritising in-situ conservation were distinct from those on supporting good animal welfare. This paper identifies similarities and differences in beliefs about zoo animal welfare and zoo husbandry practices between Europe and China, and discusses the underlying norms and values that these beliefs may reflect.


Assuntos
Criação de Animais Domésticos , Animais de Zoológico , Animais , Criação de Animais Domésticos/métodos , Animais de Zoológico/fisiologia , Comportamento Animal/fisiologia , Bem-Estar do Animal , China
8.
J Appl Anim Welf Sci ; 26(4): 634-646, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34894904

RESUMO

Education to improve knowledge of animal welfare is not a universal component of training for zoo staff, and little is reported about the perspectives of zoo staff on the need for such education. This paper reports results from structured telephone interviews of a diverse sample of eight Chinese and eight European zoo staff about aspects of zoological animal welfare, education and zoological practices. These qualitative data were thematically analyzed and key themes generated. Similar themes emerged across regions: Zoo staff consider professional attributes including motivation and enthusiasm to be important alongside formal training, zoo staff value learning opportunities but don't always feel supported, and contextual information including wild animal ecology was considered important content in zoo animal welfare education.

9.
Lab Anim ; 56(6): 561-575, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35726579

RESUMO

Descriptions of measures taken to optimize animal welfare are often absent from scientific reports of animal experiments. One reason may be that journal guidelines inadequately compel authors to provide such information. In this study, online English language versions of the 'Guidelines to authors' (GTAs) from 54 national biomedical journals were examined for neutral (unrelated to welfare) and non-neutral keywords referring to: animal welfare; the '3Rs'; the ARRIVE (2010) guidelines, and regulations pertaining to animal experimentation. Journals were selected from nine countries (UK, US, China, Canada, India, Brazil, Germany, Japan and Australia) and seven biomedical specialties (oncology, rheumatology, surgery, pharmacology, medicine, anaesthesia and veterinary medicine). Total GTA word counts varied from 1137 to 31,609. The keyword count identified per category were expressed per myriad (10,000) of total word count. One-way analyses of variance followed by post hoc Tukey pairwise comparisons revealed greater non-neutral per myriad word counts for (a) veterinary GTAs compared with medicine, oncology, rheumatology or surgery; (b) British, compared with Australian, Canadian, German and Japanese GTAs; and (c) no differences between non-neutral categories. The English language versions of GTAs of British and veterinary medical journals contain more words associated with animal welfare, the 3Rs and the ARRIVE guidelines than those from eight other countries and six other medical specialities. The exclusion of 'national' language versions from analysis precludes attempts to identify national differences in attitudes to laboratory animal welfare.


Assuntos
Experimentação Animal , Animais , Austrália , Canadá , Bem-Estar do Animal , Editoração
10.
Equine Vet J ; 54(1): 176-190, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33345356

RESUMO

BACKGROUND: Left atrial size predicts cardiac morbidity and mortality in humans and dogs. Real-time three-dimensional echocardiography (3DE) may be reliable for assessing left atrial volume (LAV) in horses. OBJECTIVES: To determine intra- and interobserver variability estimates of 3DE-LAV and compare it to that of 2DE-LAV estimates. STUDY DESIGN: Method comparison. METHODS: 3DE datasets were obtained from 40 horses, then graded for quality, creating a final study population of 22 horses. The 3DE and 2DE maximum LAV (LAVmax ) and minimum LAV (LAVmin ) were measured, and left atrial emptying volume (LA EV) and left atrial ejection fraction (LA EF) were calculated, from the same 3D dataset on four occasions using (a) a semi-automatic surface recognition algorithm and (b) a modified Simpson's method of discs. 3DE LAV measurements were repeated by a second observer. RESULTS: For 3DE, median LAVmax was 596cm3 for observer one, and 852 cm3 for observer two, LAVmin was 373 cm3 for observer one and 533 cm3 for observer two. Low intraobserver measurement variation was observed for LAVmax and LAVmin , with horse-level intraclass correlation coefficients (ICChorse ) for both observers between 76% and 85% (horse added as random effect). The interobserver ICC was 58% for LAVmax and 50% for LAVmin on averaged measurements (with observer added as random effect), indicating consistent differences between observers. While intraobserver variation was similar for 2DE LAVmax measurements, it was greater for LAVmin (ICChorse  = 67%). The intermethod ICC for 3DE vs 2DE was low at 14% for LAVmax and ~0% for LAVmin , indicating less-consistent differences with method. MAIN LIMITATIONS: Small study population, low observer number, use of different imaging modalities (fundamental frequency and octave harmonics). CONCLUSIONS: 3DE assessment of LAV was reliable, suggesting suitability for longitudinal evaluation of clinical cases. Clinicians should be aware of differences in LAV measurements between observers. More defined measurement guidelines may improve repeatability.


Assuntos
Ecocardiografia Tridimensional , Cavalos , Animais , Ecocardiografia/veterinária , Ecocardiografia Tridimensional/veterinária , Átrios do Coração/diagnóstico por imagem , Variações Dependentes do Observador , Reprodutibilidade dos Testes
11.
Animals (Basel) ; 11(7)2021 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-34359187

RESUMO

Universal frameworks for zoo animal welfare have been suggested. However, there is little evidence of a cross-cultural understanding of zoo animal welfare. This paper reports themes emerging from a qualitative study of international (European and Chinese) zoo professionals on zoo animal welfare issues. Structured telephone interviews were conducted with eight Chinese and eight European zoo staff, covering aspects of zoological animal welfare, conservation and zoological husbandry practices. These qualitative data were thematically analysed, and key themes generated. This paper describes three themes relating to 'What is animal welfare' 'Animal welfare frameworks' and 'The human element in animal welfare'. This analysis indicates that the concept of animal welfare has cultural equivalence across Europe and between Europe and China, and that zoo staff are familiar with welfare frameworks. In China, a need for senior leadership and motivating staff to improve animal welfare emerged.

12.
J Zoo Wildl Med ; 52(4): 1159-1166, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34998285

RESUMO

Leprosy has been described in Eurasian red squirrel (Sciurus vulgaris; ERS) carcasses since 2014. Studies of ERS carcasses have not provided information about incubation or disease progression in this host but have provided important insights into pathogen presence and distribution throughout the United Kingdom. Here we present field study data on 31 live ERS from an island population naturally infected with Mycobacterium leprae that were assessed longitudinally over a 2-yr time period. Clinical assessment, serologic (anti-phenolic glycolipid-I antibody [αPGL-I] detection) and molecular methods (polymerase chain reaction) were used to diagnose and categorize ERS at each assessment as a leprosy case, a leprosy suspect, colonized by M. leprae, or a contact ERS. Eight ERS (25.8%) were identified as leprosy cases: four at initial assessment, two at 6 mon and two at 24 mon after initial assessment. One ERS was categorized a leprosy suspect when it developed typical lesions 12 mon after initial assessment, despite negative serologic and molecular test results at this time, though M. leprae DNA had been isolated during the initial assessment. Seven ERS (22.6%) were categorized as colonized and of these, six were reassessed but did not develop clinical signs of leprosy within 6 (n = 2), 12 (n = 3), and 18 (n = 1) mon. Most (48.4%, n = 15) were categorized as contact ERS. Progression of leprosy lesions varied between ERS, but always increased in severity over time and was paralleled with increased antibody response. Based on our dataset, we propose the hypotheses: 1) leprosy in ERS is a chronic, slowly progressing disease in this species, similar to that described for other hosts; 2) lesions can undergo repeated ulceration-healing cycles; and 3) in some instances M. leprae DNA and αPGL-I antibodies are detectable before the onset of clinical signs of disease. Future studies addressing the progression of leprosy in ERS should follow affected animals over a longer time period and include tissue samples to pair molecular diagnostics with serologic results.


Assuntos
Hanseníase , Doenças dos Roedores , Animais , Anticorpos , Hanseníase/diagnóstico , Hanseníase/epidemiologia , Hanseníase/veterinária , Mycobacterium leprae , Reação em Cadeia da Polimerase/veterinária , Sciuridae
13.
J Feline Med Surg ; 23(8): 751-758, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33252305

RESUMO

OBJECTIVES: The study aimed to: (1) test MRI repeatability of measurements of optic nerve sheath diameter (ONSD), optic nerve diameter (OND) and eye globe transverse diameter (ETD); (2) investigate the associations between the OND, ONSD and ETD; (3) assess whether these measurements are affected by age or body weight; and (4) test the association between ONSD, OND, ETD and ONSD:ETD ratio with presumed intracranial pressure (ICP) status. METHODS: This was a retrospective and blinded study where patients were allocated to presumed normal or intracranial hypertension groups based on MRI findings. The ONSD and ETD were measured and recorded. Interclass correlation coefficient (ICC) was calculated to investigate interobserver agreement. Data were analysed using the Pearson correlation coefficient, two-sample t-test and general linear model ANOVA. RESULTS: Seventy-seven cats were included, 62 with presumed normal ICP and 15 with presumed intracranial hypertension. The ICC showed moderate-to-good reliability for all measurements. Positive correlations were identified for: (1) ETD and weight; (2) ONSD and age; (3) OND and age; (4) ONSD and ETD; (5) ONSD:ETD ratio and presumed ICP status; and (6) ONSD and presumed ICP status. No difference was detected between the presumed normal and intracranial hypertension groups and ONSD, as well as ONSD:ETD ratio and presumed ICP status when patient age was considered. CONCLUSIONS AND RELEVANCE: The measurement of the ONSD and the ONSD:ETD ratio on T2-weighted MRI might not be reliable as non-invasive tests for diagnosing intracranial hypertension in cats.


Assuntos
Doenças do Gato , Hipertensão Intracraniana , Animais , Doenças do Gato/diagnóstico por imagem , Gatos , Hipertensão Intracraniana/diagnóstico por imagem , Hipertensão Intracraniana/veterinária , Imageamento por Ressonância Magnética/veterinária , Nervo Óptico/diagnóstico por imagem , Reprodutibilidade dos Testes , Estudos Retrospectivos , Ultrassonografia
14.
Microbiology (Reading) ; 166(10): 947-965, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32886602

RESUMO

Bacterial flagella have many established roles beyond swimming motility. Despite clear evidence of flagella-dependent adherence, the specificity of the ligands and mechanisms of binding are still debated. In this study, the molecular basis of Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium flagella binding to epithelial cell cultures was investigated. Flagella interactions with host cell surfaces were intimate and crossed cellular boundaries as demarcated by actin and membrane labelling. Scanning electron microscopy revealed flagella disappearing into cellular surfaces and transmission electron microscopy of S. Typhiumurium indicated host membrane deformation and disruption in proximity to flagella. Motor mutants of E. coli O157:H7 and S. Typhimurium caused reduced haemolysis compared to wild-type, indicating that membrane disruption was in part due to flagella rotation. Flagella from E. coli O157 (H7), EPEC O127 (H6) and S. Typhimurium (P1 and P2 flagella) were shown to bind to purified intracellular components of the actin cytoskeleton and directly increase in vitro actin polymerization rates. We propose that flagella interactions with host cell membranes and cytoskeletal components may help prime intimate attachment and invasion for E. coli O157:H7 and S. Typhimurium, respectively.


Assuntos
Membrana Celular/microbiologia , Citoesqueleto/metabolismo , Escherichia coli O157/fisiologia , Flagelos/metabolismo , Salmonella typhimurium/fisiologia , Actinas/química , Actinas/metabolismo , Actinas/ultraestrutura , Animais , Aderência Bacteriana , Membrana Celular/metabolismo , Membrana Celular/patologia , Membrana Celular/ultraestrutura , Células Cultivadas , Citoesqueleto/ultraestrutura , Escherichia coli O157/genética , Escherichia coli O157/metabolismo , Flagelos/genética , Flagelos/ultraestrutura , Interações Hospedeiro-Patógeno , Humanos , Microscopia Eletrônica , Mutação , Polimerização , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo
15.
Vet Immunol Immunopathol ; 227: 110090, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32663724

RESUMO

Neonatal calves are highly susceptible to a number of diseases including those that infect via the mucosal surfaces of the respiratory and gastrointestinal tracts. In order to determine appropriate vaccine design and delivery systems, or to identify suitable immunostimulatory methods to combat these infections, a detailed understanding of the immune cell populations present at clinically relevant sites is key. Few studies have assessed the immune cell composition of the neonatal calf lung and comparisons with circulating immune cells in the blood are lacking. We describe immune cell populations present in the peripheral blood, bronchoalveolar lavage (BAL) fluid and lung tissue of young disease-free calves. Flow cytometric analysis revealed significant differences in cell subset distribution between the peripheral blood and respiratory tract, and between compartments within the respiratory tract. Notably, whereas WC1+ γδ TCR + T lymphocytes dominate the peripheral blood, both the BAL fluid and lung tissue contained a high proportion of myeloid cells which expressed CD14 and CD172a (SIRPα). Very low numbers of tissue myeloid cells expressed MHC Class II in comparison to circulating myeloid cells in the blood. Respiratory tract tissues had low frequencies of CD4+ and CD8 + T lymphocytes, which were significantly lower than in the blood. Differences in the proportion of NKp46+ natural killer cells were also observed between tissue compartments. In order to target vaccines or immunostimulatory therapeutics appropriately, these differences in immune cell populations in tissue compartments should be taken into consideration.


Assuntos
Líquido da Lavagem Broncoalveolar/imunologia , Contagem de Linfócitos/veterinária , Sistema Respiratório/imunologia , Subpopulações de Linfócitos T/imunologia , Animais , Animais Recém-Nascidos/imunologia , Líquido da Lavagem Broncoalveolar/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Bovinos , Citometria de Fluxo , Células Matadoras Naturais/imunologia , Pulmão/citologia , Pulmão/imunologia , Masculino , Sistema Respiratório/citologia
16.
Nat Ecol Evol ; 4(7): 934-939, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32341514

RESUMO

Apart from its global health importance, measles is a paradigm for the low-dimensional mechanistic understanding of local nonlinear population interactions. A central question for spatio-temporal dynamics is the relative roles of hierarchical spread from large cities to small towns and metapopulation transmission among local small population clusters in measles persistence. Quantifying this balance is critical to planning the regional elimination and global eradication of measles. Yet, current gravity models do not allow a formal comparison of hierarchical versus metapopulation spread. We address this gap with a competing-risks framework, capturing the relative importance of competing sources of reintroductions of infection. We apply the method to the uniquely spatio-temporally detailed urban incidence dataset for measles in England and Wales, from 1944 to the infection's vaccine-induced nadir in the 1990s. We find that despite the regional influence of a few large cities (for example, London and Liverpool), metapopulation aggregation in neighbouring towns and cities played an important role in driving national dynamics in the prevaccination era. As vaccination levels increased in the 1970s and 1980s, the signature of spatially predictable spread diminished: increasingly, infection was introduced from unidentifiable random sources possibly outside regional metapopulations. The resulting erratic dynamics highlight the challenges of identifying shifting sources of infection and characterizing patterns of incidence in times of high vaccination coverage. More broadly, the underlying incidence and demographic data, accompanying this paper, will also provide an important resource for exploring nonlinear spatiotemporal population dynamics.


Assuntos
Epidemias , Sarampo/epidemiologia , Surtos de Doenças , Inglaterra , Humanos , País de Gales
17.
J Vet Med Educ ; 47(2): 218-229, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31194631

RESUMO

A major challenge in admissions to veterinary medical degrees is to select those students most suitable for clinical training programs and careers from a large pool of applicants with very high academic ability. Predicting the success of students in a veterinary course is challenging, and relatively few objective studies have been undertaken to identify factors that facilitate progression through this educational experience. Prior educational attainment is considered by some to be a good predictor of success at undergraduate level. The aims of this study were to analyze intake data such as educational history and demographic factors of students entering the University of Edinburgh and to investigate possible relationships between these data and academic performance in the first year at veterinary school. Data were collated for three veterinary intakes, including school qualification, subjects, grades, grade point average (GPA), degree classification, domicile, gender, and age. Performance was measured by marks achieved in first-year veterinary degree examinations. Relationships between marks and the influence of intake variables were statistically analyzed via ANOVA. For school-leaving entrants, the presence of straight A grades in school was linked to better exam performance. Students with an A grade in Chemistry or Biology performed better; A grades in Mathematics and Physics did not show such a consistent linkage with performance. Higher GPA was associated with better performance in first year for students in a graduate entry program. This study shows prior educational attainment does appear to be linked with subsequent performance in the first year at veterinary school.


Assuntos
Educação em Veterinária , Critérios de Admissão Escolar , Faculdades de Medicina Veterinária , Estudantes de Medicina , Logro , Animais , Educação em Veterinária/normas , Avaliação Educacional , Critérios de Admissão Escolar/estatística & dados numéricos , Faculdades de Medicina Veterinária/estatística & dados numéricos , Estudantes de Medicina/estatística & dados numéricos
18.
Virology ; 526: 155-164, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30390564

RESUMO

IFNγ is a key regulator of inflammatory responses but its role in influenza A virus (IAV) pathogenesis is unclear. Our studies show that infection of mice lacking the IFNγ receptor (IFNγR-/-) at a dose which caused severe disease in wild type 129 Sv/Ev (WT) mice resulted in milder clinical symptoms and significantly lower lung virus titers by 6 days post-infection (dpi). Viral spread was reduced in IFNγR-/- lungs at 2 and 4 dpi. Levels of inflammatory cytokines and chemokines were lower in IFNγR-/- mice at 2 dpi and there was less infiltration of monocyte/macrophage lineage cells than in WT mice. There was no difference in CD4+ and CD8+ T cells and alveolar macrophages in the bronchoalveolar lavage fluid (BALF) at 2 and 4 dpi but by 4 dpi IFNγR-/- mice had significantly higher percentages of neutrophils. Our data strongly suggest that IAV can use the inflammatory response to promote viral spread.


Assuntos
Vírus da Influenza A/patogenicidade , Infecções por Orthomyxoviridae/fisiopatologia , Receptores de Interferon/genética , Transdução de Sinais , Animais , Líquido da Lavagem Broncoalveolar/imunologia , Citocinas/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Pulmão/virologia , Macrófagos/imunologia , Camundongos , Camundongos Transgênicos , Neutrófilos/imunologia , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologia , Transdução de Sinais/genética , Carga Viral
19.
C R Biol ; 341(4): 235-244, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29752201

RESUMO

The growth of the maxillary canine teeth of the babirusa (genus Babyrousa) was studied on a sample of 149 adult male babirusa skulls from twenty-two international museum and private collections. Skulls from Buru, Sulawesi and the Togian Islands were represented. The continuous growth process was summarised into five stages ('A'-'E') according to the position of the tip of the tooth over the bones of the skull. The supracutaneous portion of the tooth grew in a curve-linear fashion dorso-caudally, and was orientated such that the tips grew towards the midline of the cranium. The teeth of Sulawesi and Togian babirusa grew more dorsally over the nasal and frontal bones. Measurements were made on a subset of 45 teeth from Sulawesi babirusa skulls. The subcutaneous portion of the maxillary canine tooth (n=22) increased in size from 37.3mm (95% CI: 29.9-44.4mm) in growth stage 'B' to 54.3mm (49.4-59.2mm) in growth stage 'E' as the erupted portion of the tooth (n=19) lengthened from 81.3mm (43.8-118.9mm) in growth stage 'A' to 215.3mm (177.8-252.9mm) in growth stage 'E'. The apical end of the tooth was open and thin-walled. The lumen of the tooth was filled with a cone of well vascularised dental pulp that extended almost to the tip of the tooth. The angle of curvature of the tooth within the alveolus (n=22) decreased from 19.8 (17.3-22.3) degrees in growth stage 'B' to 7.4 (5.7-9.0) degrees in growth stage 'E'. The corresponding supracutaneous angle of curvature (n=25) reduced from 36.8 (33.6-40.1) degrees in growth stage 'A' to 10.7 (8.6-12.8) degrees in growth stage 'E'.


Assuntos
Suínos/anatomia & histologia , Dente/anatomia & histologia , Animais , Indonésia , Masculino , Crânio
20.
Food Microbiol ; 74: 163-170, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29706332

RESUMO

Campylobacter is the most common cause of bacterial food-borne diarrhoeal disease worldwide. Chicken meat is considered the main source of human infection; however, C. jejuni and C. coli have also been reported in a range of livestock and wildlife species, including pheasants. Wild pheasant meat reaches the consumer's table because of hunting but there is a lack of information concerning the risk of Campylobacter infection in humans. This study aimed to determine the prevalence of Campylobacter in wild game pheasants in Scotland, to identify the main sequence types (STs) present and to evaluate their impact on public health. A total of 287 caecal samples from five Scottish regions were collected during the hunting season 2013/2014. Campylobacter was detected and enumerated using standard culture methods. PCR and High Throughput Multi Locus Sequence Typing (HiMLST) were used for species identification and sequence typing. In total, 36.6% of 287 caecal samples (n = 105; 95% CI: 14-59.2) were Campylobacter positive. Using PCR, 62.6% of samples (n = 99) were identified as C. coli and 37.4% as C. jejuni. HiMLST (n = 80) identified 19 different STs. ST-828 (n = 19) was the most common, followed by ST-827 (n = 12) and ST19 (n = 7). Sixteen of the 19 STs isolated are present in humans and eight are C. coli STs that account for 6.96% of human infections, although the overall risk to public health from pheasant meat is still considered to be low.


Assuntos
Animais Selvagens/microbiologia , Infecções por Campylobacter/virologia , Campylobacter/isolamento & purificação , Galliformes/microbiologia , Aves Domésticas/microbiologia , Saúde Pública , Animais , Carga Bacteriana , Campylobacter/classificação , Campylobacter/genética , Campylobacter/patogenicidade , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , DNA Bacteriano/genética , Microbiologia de Alimentos , Doenças Transmitidas por Alimentos/microbiologia , Geografia , Humanos , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase , Prevalência , Escócia/epidemiologia , Análise de Sequência
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