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1.
Z Gesundh Wiss ; : 1-8, 2022 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-36404931

RESUMO

Aim/Purpose: The article seeks to articulate a consensus of the opinions of a group of subject experts about the principles and strategies of inclusive physical activity. Methods: A 3-stage Delphi study involving a group of 34 Europe-based subject specialists was used to articulate shared expert opinions on the main research question: What are the key principles (general theories, values, or framework) that should guide practice of inclusive approaches to physical activity? What are the key strategies (practical approaches that can promote inclusive physical activity) of inclusive approaches to physical activity? Results: Four core principles and four core strategies (and six less-supported principles/strategies for each) were identified through this process. The core principles were: focus on participants' needs; include disabled people in planning; focus on ability, not disability; and promote equal opportunities. The four core strategies were: adapt the rules and aims of the programme to the abilities of participants; apply adaptability of teaching/coaching methods; be accessible and available to participants; and establish models to make sure participants' voices are heard. Conclusions: The article concludes by offering ten concepts - drawn from the empirical findings - that might act as a starting-point for the development of the concept for an inclusive physical activity programme.

2.
Vaccine X ; 12: 100230, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36276875

RESUMO

Peptide vaccine is not effective due to its low immunogenicity. To improve the efficacy of peptide vaccine against COVID-19, a novel method was developed by mixing a COVID-19 peptide vaccine with a tetanus vaccine. In this study, intramuscular injection of a mixture of COVID-19 peptide vaccine and tetanus vaccine twice, i.e., first dose on day 0 and second dose on day 21, induced neutralizing antibodies against authentic virus of SARS-CoV-2 Delta variant in a horse. Horse serum of day 35, i.e., two weeks after the second dose, neutralized authentic virus of SARS-CoV-2 Delta variant, equal to half effectiveness of human serum from vaccinees of Moderna COVID-19 vaccine. However, neither horse serum nor human serum neutralized Omicron variant authentic virus. No side effects were observed after each dose. This study indicates intramuscular injection of a mixture of COVID-19 peptide vaccine and tetanus vaccine may work in humans to improve peptide vaccine efficacy against SARS-CoV-2.

3.
J Vet Intern Med ; 34(4): 1674-1679, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32588478

RESUMO

BACKGROUND: Small ruminants presented to tertiary care facilities commonly suffer from severe protein-calorie malnutrition. Some of these patients require parenteral nutrition (PN; amino acids and dextrose with or without lipids) during hospitalization. Refeeding syndrome, a potentially fatal shift of electrolytes seen in malnourished patients during refeeding, may occur. OBJECTIVE: (a) To report the prevalence of refeeding syndrome in small ruminants receiving PN and (b) to determine risk factors for the development of refeeding syndrome. ANIMALS: Hospitalized small ruminants (n = 20) that received PN from 2010 to 2018 and that had serial (≥2) monitoring of serum electrolyte concentrations after initiation of PN. METHODS: Retrospective case series. Refeeding syndrome was defined as the presence of at least 2 of the following electrolyte abnormalities after initiation of PN: hypophosphatemia, hypokalemia, hypomagnesemia, or some combination of these. Data was analyzed using Fisher's exact test, followed by univariate logistic regression. RESULTS: Eleven of 20 (55%) animals met the definition of refeeding syndrome. Mean minimum serum phosphorus concentration in animals with refeeding syndrome was 1.96 ± 0.69 mg/dL (reference range, 4.2-7.6 mg/dL). Eleven of 20 animals survived to discharge. Survival rate did not differ significantly between refeeding cases (4/11, 36.3%) and nonrefeeding cases (7/9, 77.8%; P = .09). Mean serum phosphorus concentration was significantly lower in nonsurvivors than in survivors (1.88 ± 0.10 mg/dL vs 4.32 ± 0.70 mg/dL, P = .006). CONCLUSIONS AND CLINICAL IMPORTANCE: We report the prevalence of refeeding syndrome in small ruminants receiving PN. Clinicians should anticipate refeeding syndrome after initiation of PN and consider pre-emptive supplementation with phosphorus, potassium, magnesium, or some combination of these.


Assuntos
Doenças das Cabras/metabolismo , Nutrição Parenteral/veterinária , Síndrome da Realimentação/veterinária , Doenças dos Ovinos/metabolismo , Animais , Eletrólitos/sangue , Feminino , Cabras , Hipopotassemia/epidemiologia , Hipopotassemia/veterinária , Hipofosfatemia/epidemiologia , Hipofosfatemia/veterinária , Magnésio/sangue , Masculino , Nutrição Parenteral/efeitos adversos , Prevalência , Síndrome da Realimentação/sangue , Síndrome da Realimentação/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Ovinos
4.
Front Public Health ; 5: 208, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29021977

RESUMO

On March 24 and 25, 2017 researchers and clinicians from around the world met at Temple University in Philadelphia to discuss the current knowledge of Mycobacterium avium ssp. paratuberculosis (MAP) and its relationship to human disease. The conference was held because of shared concern that MAP is a zoonotic bacterium that poses a threat not only to animal health but also human health. In order to further study this problem, the conferees discussed ways to improve MAP diagnostic tests and discussed potential future anti-MAP clinical trials. The conference proceedings may be viewed on the www.Humanpara.org website. A summary of the salient work in this field is followed by recommendations from a majority of the conferees.

5.
PLoS One ; 11(8): e0160353, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27494144

RESUMO

Johne's disease (JD) is a chronic, intestinal infection of cattle, caused by Mycobacterium avium subsp. paratuberculosis (MAP). It results in granulomatous inflammation of the intestinal lining, leading to malabsorption, diarrhea, and weight loss. Crohn's disease (CD), a chronic, inflammatory gastrointestinal disease of humans, has many clinical and pathologic similarities to JD. Dysbiosis of the enteric microbiota has been demonstrated in CD patients. It is speculated that this dysbiosis may contribute to the intestinal inflammation observed in those patients. The purpose of this study was to investigate the diversity patterns of fecal bacterial populations in cattle infected with MAP, compared to those of uninfected control cattle, using phylogenomic analysis. Fecal samples were selected to include samples from 20 MAP-positive cows; 25 MAP-negative herdmates; and 25 MAP-negative cows from a MAP-free herd. The genomic DNA was extracted; PCR amplified sequenced on a 454 Roche platform, and analyzed using QIIME. Approximately 199,077 reads were analyzed from 70 bacterial communities (average of 2,843 reads/sample). The composition of bacterial communities differed between the 3 treatment groups (P < 0.001; Permanova test). Taxonomic assignment of the operational taxonomic units (OTUs) identified 17 bacterial phyla across all samples. Bacteroidetes and Firmicutes constituted more than 95% of the bacterial population in the negative and exposed groups. In the positive group, lineages of Actinobacteria and Proteobacteria increased and those of Bacteroidetes and Firmicutes decreased (P < 0.001). Actinobacteria was highly abundant (30% of the total bacteria) in the positive group compared to exposed and negative groups (0.1-0.2%). Notably, the genus Arthrobacter was found to predominate Actinobacteria in the positive group. This study indicates that MAP-infected cattle have a different composition of their fecal microbiota than MAP-negative cattle.


Assuntos
Disbiose , Fezes/microbiologia , Mycobacterium avium subsp. paratuberculosis/patogenicidade , Paratuberculose/microbiologia , Animais , Biodiversidade , Bovinos , Doenças dos Bovinos/microbiologia , Feminino , Microbioma Gastrointestinal/genética , Consórcios Microbianos/genética , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Filogenia
6.
Avian Dis ; 60(1): 90-4, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26953952

RESUMO

This report describes an outbreak of type C botulism in two organic, free-range commercial layer farms in the Midwest. Hens affected were 64-wk-old Hy-Line brown hens and 34-wk-old Hy-Line brown hens owned by the same company, but housed on different premises, with approximately 20,000 birds per house. Mortality over the 2 wk of investigation was estimated to be up to 8% and 2.8%, respectively, with birds acting listless, lethargic, and depressed. Clinical signs consisted of progressive paralysis, and severely affected birds were moribund and laterally recumbent. Hens had ruffled feathers that easily epilated, with loss of muscular tone in the neck, tail, and wings. Hens had closed eyes and were reluctant to move. There were no significant gross or histopathologic lesions. Intestinal samples were submitted to the University of Pennsylvania Botulism Diagnostic Laboratory for real-time PCR and were positive for Clostridium botulinum organisms containing the Type C neurotoxin gene. Speculations on the source of the botulinum toxins include poor mortality removal leading to cannibalism of decomposing carcasses, as well as birds on the farm having access to putrid carcasses in the compost pile from a hole in their outdoor access fence.


Assuntos
Botulismo/veterinária , Galinhas , Clostridium botulinum/isolamento & purificação , Surtos de Doenças/veterinária , Doenças das Aves Domésticas/epidemiologia , Animais , Botulismo/epidemiologia , Botulismo/microbiologia , Clostridium botulinum/genética , Feminino , Intestinos/microbiologia , Meio-Oeste dos Estados Unidos/epidemiologia , Doenças das Aves Domésticas/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária
7.
Am J Vet Res ; 77(2): 151-5, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27027708

RESUMO

OBJECTIVE: To determine serum and tissue concentrations of gallium (Ga) after oral administration of gallium nitrate (GaN) and gallium maltolate (GaM) to neonatal calves. ANIMALS: 8 healthy neonatal calves. PROCEDURES: Calves were assigned to 1 of 2 groups (4 calves/group). Gallium (50 mg/kg) was administered as GaN or GaM (equivalent to 13.15 mg of Ga/kg for GaN and 7.85 mg of Ga/kg for GaM) by oral gavage once daily for 5 days. Blood samples were collected 0, 0.25, 0.5, 1, 2, 4, 8, 12, and 24 hours after Ga administration on day 1; 4 and 24 hours after Ga administration on days 2, 3, and 4; and 4, 12, and 24 hours after Ga administration on day 5. On day 6, calves were euthanized and tissue samples were obtained. Serum and tissue Ga concentrations were measured by use of mass spectrometry. RESULTS: Data were adjusted for total Ga dose, and comparisons were made between the 2 groups. Calves receiving GaM had a significantly higher dose-adjusted area under the curve and dose-adjusted maximum serum Ga concentration than did calves receiving GaN. Despite receiving less Ga per dose, calves receiving GaM had tissue Ga concentrations similar to those for calves receiving GaN. CONCLUSIONS AND CLINICAL RELEVANCE: In this study, calves receiving GaM had significantly higher Ga absorption than did calves receiving GaN. These findings suggested that GaM might be useful as a prophylactic agent against Mycobacterium avium subsp paratuberculosis infection in neonatal calves.


Assuntos
Gálio/sangue , Compostos Organometálicos/farmacocinética , Pironas/farmacocinética , Administração Oral , Animais , Animais Recém-Nascidos , Bovinos , Gálio/administração & dosagem , Gálio/metabolismo , Gálio/farmacocinética , Masculino , Espectrometria de Massas , Compostos Organometálicos/administração & dosagem , Compostos Organometálicos/sangue , Pironas/administração & dosagem , Pironas/sangue
8.
Vet J ; 202(1): 195-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25155307

RESUMO

Johne's disease (JD) is an enteric infection of cattle and other ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP). This study compared the antimicrobial activities of gallium nitrate (GaN) and gallium maltolate (GaM) against two field MAP isolates by use of broth culture. The concentrations that resulted in 99% growth inhibition of isolates 1 and 2 were, respectively, 636 µM and 183 µM for GaN, and 251 µM and 142 µM for GaM. For both isolates, time to detection was significantly higher for GaM than GaN. These results suggest that GaM is more efficient than GaN in inhibiting MAP growth in vitro.


Assuntos
Antibacterianos/farmacologia , Gálio/farmacologia , Mycobacterium avium subsp. paratuberculosis/efeitos dos fármacos , Compostos Organometálicos/farmacologia , Pironas/farmacologia
9.
Vet J ; 199(1): 157-61, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24252222

RESUMO

Botulism in horses in the USA is attributed to Clostridium botulinum types A, B or C. In this study, a duplex quantitative real-time PCR (qPCR) for detection of the neurotoxin genes of C. botulinum types A and B, and a singleplex qPCR for detection of the neurotoxin gene of C. botulinum type C, were optimized and validated for equine gastrointestinal, faecal and feed samples. The performance of these assays was evaluated and compared to the standard mouse bioassay (MBA) using 148 well-characterized samples, most of which were acquired from a repository of veterinary diagnostic samples from cases of botulism: 106 samples positive for C. botulinum (25 type A, 27 type B, 28 type C, 1 type D and 25 type E) and 42 negative samples. The sensitivities of the qPCR assays were 89%, 86% and 96% for C. botulinum types A, B and C, respectively. The overall sensitivity of the mouse bioassay for types A, B and C was 81%. The specificities of the qPCR assays were 99-100% and the specificity of the mouse bioassay was 95%.


Assuntos
Clostridium botulinum tipo A/genética , Clostridium botulinum tipo B/genética , Clostridium botulinum tipo C/genética , Cavalos , Neurotoxinas/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Animais , Bioensaio , Camundongos
10.
Can Vet J ; 54(11): 1083-5, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24179246

RESUMO

The goal of this study was to determine the persistence of Mycobacterium avium subsp. paratuberculosis (MAP) in soil, crops, and ensiled feeds following manure spreading. This bacterium was often found in soil samples, but less frequently in harvested feeds and silage. Spreading of manure on fields used for crop harvest is preferred to spreading on grazing pastures.


Persistance deMycobacterium aviumssp.paratuberculosisdans le sol, les récoltes et l'ensilage après l'épandage de fumier dans des fermes laitières infectées. Le but de cette étude était de déterminer la persistance de Mycobacterium avium ssp. paratuberculosis (MAP) dans le sol, les récoltes et l'ensilage après l'épandage de fumier. Cette bactérie se trouvait souvent dans des échantillons de sol, mais moins fréquemment dans les récoltes d'aliments pour le bétail et l'ensilage. L'épandage de fumier dans les champs utilisés pour la récolte des cultures est préféré à l'épandage dans les pâturages.(Traduit par Isabelle Vallières).


Assuntos
Doenças dos Bovinos/microbiologia , Produtos Agrícolas/microbiologia , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Paratuberculose/microbiologia , Silagem/microbiologia , Microbiologia do Solo , Animais , Bovinos , Indústria de Laticínios , Esterco/microbiologia , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Tempo
11.
Vet J ; 194(1): 118-20, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22537645

RESUMO

Clostridium botulinum type B is estimated to cause more than 85% of cases of equine botulism in the United States, as well as many outbreaks in cattle. In this study, a quantitative real-time polymerase chain reaction for detection of the neurotoxin gene of C. botulinum type B was compared to the mouse bioassay using 45 positive and 43 negative samples of equine, bovine or associated environmental origin. The sensitivity of the qPCR assay was 96%, whereas the sensitivity of the mouse bioassay was 84%. The specificity of the qPCR assay was 95% and the specificity of the mouse bioassay was 100%.


Assuntos
Toxinas Botulínicas/metabolismo , Botulismo/diagnóstico , Doenças dos Bovinos/diagnóstico , Clostridium botulinum/classificação , Doenças dos Cavalos/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Animais , Bioensaio/métodos , Toxinas Botulínicas/genética , Toxinas Botulínicas Tipo A , Botulismo/microbiologia , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Cavalos/microbiologia , Cavalos , Camundongos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Vet Clin North Am Food Anim Pract ; 27(3): 537-46, v, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22023832

RESUMO

Paratuberculosis in ruminants is characterized by oral ingestion of Mycobacterium avium subsp. paratuberculosis (MAP), followed by a long incubation period during which time MAP is able to survive within the host's macrophages. Initially the infection is held in check by the host's cell-mediated immune response, but gradually the host loses control of the infection. The infection incites a granulomatous inflammatory response in intestinal tissue and mesenteric lymph nodes, resulting in protein-losing enteropathy, malabsorption, diarrhea, weight loss, and edema.


Assuntos
Mycobacterium avium subsp. paratuberculosis/patogenicidade , Paratuberculose/microbiologia , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Suscetibilidade a Doenças/veterinária , Ruminantes
13.
Am J Vet Res ; 72(9): 1243-6, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21879983

RESUMO

OBJECTIVE: To evaluate the in vitro susceptibility of various field isolates of Mycobacterium avium subsp paratuberculosis (MAP) to gallium nitrate. SAMPLE: 10 isolates of MAP, including 4 isolated from cattle, 2 isolated from bison, 1 isolated from an alpaca, and 3 isolated from humans. PROCEDURES: The in vitro susceptibility to gallium nitrate was tested by use of broth culture with detection of MAP growth by means of a nonradiometric automated detection method. For each MAP isolate, a series of 7 dilutions of gallium nitrate (concentrations ranging from 200 to 1,000 µM) were tested. Gallium nitrate was considered to have caused 90% and 99% inhibition of the MAP growth when the time to detection for culture of the MAP stock solution and a specific concentration of gallium nitrate was delayed and was similar to that obtained for culture of the MAP stock solution (without the addition of gallium nitrate) diluted 1:10 and 1:100, respectively. RESULTS: Gallium nitrate inhibited MAP growth in all 10 isolates. The susceptibility to gallium nitrate was variable among isolates, and all isolates of MAP were inhibited in a dose-dependent manner. Overall, the concentration that resulted in 90% inhibition ranged from < 200 µM for the most susceptible isolates to 743 µM for the least susceptible isolates. CONCLUSIONS AND CLINICAL RELEVANCE: Gallium nitrate had activity against all 10 isolates of MAP tested in vitro and could potentially be used as a prophylactic agent to aid in the control of MAP infections during the neonatal period.


Assuntos
Doenças dos Bovinos/tratamento farmacológico , Gálio/farmacologia , Mycobacterium avium subsp. paratuberculosis/efeitos dos fármacos , Paratuberculose/tratamento farmacológico , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Meios de Cultura , Mycobacterium avium subsp. paratuberculosis/crescimento & desenvolvimento , Paratuberculose/microbiologia
14.
J Vet Emerg Crit Care (San Antonio) ; 21(3): 273-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21631714

RESUMO

OBJECTIVE: To describe the clinical presentation, case management, and outcome in 2 foals with Rhodococcus equi infection associated with presumptive severe immune-mediated hemolytic anemia. SERIES SUMMARY: Two foals diagnosed with R. equi pneumonia on the basis of tracheal wash cultures, thoracic radiographs, and thoracic ultrasonography were concurrently diagnosed with hemolytic anemia. Both foals required whole blood transfusions, and were treated with the antimicrobial combination of rifampin and a macrolide (eg, clarithromycin, erythromycin, or azithromycin). Dexamethasone was used to prevent further hemolysis in both foals, and to treat acute lung injury/acute respiratory distress syndrome in 1 of the foals. Both foals survived, and required prolonged antimicrobial therapy. NEW OR UNIQUE INFORMATION PROVIDED: Although extra-pulmonary disorders are commonly diagnosed in foals infected with R. equi, hemolytic anemia is rarely described. Dexamethasone is considered the treatment of choice for immune-mediated hemolytic anemia, but may be contra-indicated in foals with severe bacterial infections. In these foals, a relatively low dose and short duration of dexamethasone was utilized in an attempt to minimize immune suppression, although early discontinuation in 1 foal precipitated a second hemolytic crisis.


Assuntos
Infecções por Actinomycetales/veterinária , Anemia Hemolítica Autoimune/veterinária , Doenças dos Cavalos/etiologia , Doenças dos Cavalos/microbiologia , Pneumonia Bacteriana/veterinária , Infecções por Actinomycetales/complicações , Infecções por Actinomycetales/tratamento farmacológico , Anemia Hemolítica Autoimune/etiologia , Anemia Hemolítica Autoimune/microbiologia , Animais , Dexametasona/uso terapêutico , Glucocorticoides/uso terapêutico , Doenças dos Cavalos/tratamento farmacológico , Cavalos , Pneumonia Bacteriana/complicações , Pneumonia Bacteriana/tratamento farmacológico , Pneumonia Bacteriana/microbiologia , Rhodococcus equi , Resultado do Tratamento
15.
Can Vet J ; 52(2): 181-3, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21532827

RESUMO

This report describes a unique case of presumed migration of Parelaphastrongylus tenuis through the spinal cord into the eye of a llama where it survived and matured within the ocular environment. Blindness of the eye was most likely attributable to migration of the parasite through the central nervous tissue.


Assuntos
Camelídeos Americanos/parasitologia , Infecções Oculares Parasitárias/veterinária , Infecções por Nematoides/veterinária , Animais , Cegueira/etiologia , Cegueira/veterinária , Infecções Oculares Parasitárias/complicações , Infecções Oculares Parasitárias/diagnóstico , Evolução Fatal , Feminino , Infecções por Nematoides/complicações , Infecções por Nematoides/diagnóstico
16.
Prev Vet Med ; 101(1-2): 18-34, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-21601933

RESUMO

The Standards for Reporting of Diagnostic Accuracy (STARD) statement (www.stard-statement.org) was developed to encourage complete and transparent reporting of key elements of test accuracy studies in human medicine. The statement was motivated by widespread evidence of bias in test accuracy studies and the finding that incomplete or absent reporting of items in the STARD checklist was associated with overly optimistic estimates of test performance characteristics. Although STARD principles apply broadly, specific guidelines do not exist to account for unique considerations in livestock studies such as herd tests, potential use of experimental challenge studies, a more diverse group of testing purposes and sampling designs, and the widespread lack of an ante-mortem reference standard with high sensitivity and specificity. The objective of the present study was to develop a modified version of STARD relevant to paratuberculosis (Johne's disease) in ruminants. Examples and elaborations for each of the 25 items were developed by a panel of experts using a consensus-based approach to explain the items and underlying concepts. The new guidelines, termed STRADAS-paraTB (Standards for Reporting of Animal Diagnostic Accuracy Studies for paratuberculosis), should facilitate improved quality of reporting of the design, conduct and results of paratuberculosis test accuracy studies which were identified as "poor" in a review published in 2008 in Veterinary Microbiology.


Assuntos
Técnicas de Laboratório Clínico/veterinária , Testes Diagnósticos de Rotina/veterinária , Paratuberculose/diagnóstico , Ruminantes , Animais , Técnicas de Laboratório Clínico/métodos , Técnicas de Laboratório Clínico/normas , Consenso , Testes Diagnósticos de Rotina/métodos , Testes Diagnósticos de Rotina/normas , Relações Interprofissionais , Guias de Prática Clínica como Assunto , Sensibilidade e Especificidade , Manejo de Espécimes/normas , Manejo de Espécimes/veterinária
17.
J Transl Med ; 8: 125, 2010 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-21108848

RESUMO

BACKGROUND: Magnetic resonance imaging has been used in the diagnosis of human prion diseases such as sCJD and vCJD, but patients are scanned only when clinical signs appear, often at the late stage of disease. This study attempts to answer the questions "Could MRI detect prion diseases before clinical symptoms appear?, and if so, with what confidence?" METHODS: Scrapie, the prion disease of sheep, was chosen for the study because sheep can fit into a human sized MRI scanner (and there were no large animal MRI scanners at the time of this study), and because the USDA had, at the time of the study, a sizeable sample of scrapie exposed sheep, which we were able to use for this purpose. 111 genetically susceptible sheep that were naturally exposed to scrapie were used in this study. RESULTS: Our MRI findings revealed no clear, consistent hyperintense or hypointense signal changes in the brain on either clinically affected or asymptomatic positive animals on any sequence. However, in all 37 PrPSc positive sheep (28 asymptomatic and 9 symptomatic), there was a greater ventricle to cerebrum area ratio on MRI compared to 74 PrPSc negative sheep from the scrapie exposed flock and 6 control sheep from certified scrapie free flocks as defined by immunohistochemistry (IHC). CONCLUSIONS: Our findings indicate that MRI imaging can detect diffuse cerebral atrophy in asymptomatic and symptomatic sheep infected with scrapie. Nine of these 37 positive sheep, including 2 one-year old animals, were PrPSc positive only in lymph tissues but PrPSc negative in the brain. This suggests either 1) that the cerebral atrophy/neuronal loss is not directly related to the accumulation of PrPSc within the brain or 2) that the amount of PrPSc in the brain is below the detectable limits of the utilized immunohistochemistry assay. The significance of these findings remains to be confirmed in human subjects with CJD.


Assuntos
Encéfalo/patologia , Síndrome de Creutzfeldt-Jakob/patologia , Modelos Animais de Doenças , Imageamento por Ressonância Magnética , Animais , Atrofia , Ventrículos Cerebrais/patologia , Humanos , Tamanho do Órgão , Curva ROC , Ovinos
18.
J Vet Diagn Invest ; 22(5): 677-83, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20807920

RESUMO

Real-time quantitative polymerase chain reaction (qPCR) testing for Mycobacterium avium subspecies paratuberculosis (MAP) in fecal samples is a rapid alternative to culture on Herrold egg yolk medium (HEYM), the traditional antemortem reference test for MAP. Although the sensitivity and specificity of these 2 tests have been estimated based on dichotomized test results, the correlation between real-time qPCR threshold cycle (Ct) values and colony-forming units (CFU) on HEYM for fresh and thawed samples has not been evaluated. The objectives of the present study were to estimate the correlation and association between Ct and CFU in fresh and thawed pooled fecal and environmental samples. Results of HEYM culture of 1,997 pooled fecal samples from cows in 14 herds, and 802 environmental samples from 109 dairies nationwide were negatively (inversely) correlated with their respective real-time qPCR results. The Spearman's rank correlation between Ct and CFU was good (-0.66) in fresh and thawed pooled fecal samples, and excellent (-0.76) and good (-0.61) in fresh and thawed environmental samples, respectively. The correlation varied from good (-0.53) to excellent (-0.90) depending on the number of samples in a fecal pool. Truncated regression models indicated a significant negative association between Ct and CFU in fecal pools and environmental samples. The use of real-time qPCR instead of HEYM can yield rapid, quantitative estimates of MAP load and allow for incorporation of real-time qPCR results of pooled and environmental samples in testing strategies to identify dairy cow groups with the highest MAP shedding.


Assuntos
Meios de Cultura , Gema de Ovo , Mycobacterium avium subsp. paratuberculosis/genética , Reação em Cadeia da Polimerase/métodos , Animais , California , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Ensaio de Unidades Formadoras de Colônias , Indústria de Laticínios , Gema de Ovo/microbiologia , Meio Ambiente , Fezes/microbiologia , Feminino , Mycobacterium avium subsp. paratuberculosis/crescimento & desenvolvimento , New York , Paratuberculose/epidemiologia , Paratuberculose/microbiologia , Pennsylvania , Análise de Regressão , Vermont
19.
Can Vet J ; 51(2): 198-200, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20436867

RESUMO

This study investigated the susceptibility of 1- to 2-year-old cattle to Mycobacterium avium subsp. paratuberculosis (MAP) on pasture previously grazed by infected cattle. The exposure of yearling cattle to pastures contaminated with MAP resulted in infection with MAP, showing that age resistance to infection can be overcome by pressure of infection.


Assuntos
Doenças dos Bovinos/microbiologia , Exposição Ambiental , Paratuberculose/transmissão , Animais , Bovinos , Doenças dos Bovinos/transmissão , Indústria de Laticínios , Fezes/microbiologia , Masculino , Mycobacterium avium subsp. paratuberculosis , Paratuberculose/genética , Poaceae/microbiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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