Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.266
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Nature ; 630(8016): 447-456, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38839969

RESUMO

Increasing rates of autoimmune and inflammatory disease present a burgeoning threat to human health1. This is compounded by the limited efficacy of available treatments1 and high failure rates during drug development2, highlighting an urgent need to better understand disease mechanisms. Here we show how functional genomics could address this challenge. By investigating an intergenic haplotype on chr21q22-which has been independently linked to inflammatory bowel disease, ankylosing spondylitis, primary sclerosing cholangitis and Takayasu's arteritis3-6-we identify that the causal gene, ETS2, is a central regulator of human inflammatory macrophages and delineate the shared disease mechanism that amplifies ETS2 expression. Genes regulated by ETS2 were prominently expressed in diseased tissues and more enriched for inflammatory bowel disease GWAS hits than most previously described pathways. Overexpressing ETS2 in resting macrophages reproduced the inflammatory state observed in chr21q22-associated diseases, with upregulation of multiple drug targets, including TNF and IL-23. Using a database of cellular signatures7, we identified drugs that might modulate this pathway and validated the potent anti-inflammatory activity of one class of small molecules in vitro and ex vivo. Together, this illustrates the power of functional genomics, applied directly in primary human cells, to identify immune-mediated disease mechanisms and potential therapeutic opportunities.


Assuntos
Inflamação , Macrófagos , Proteína Proto-Oncogênica c-ets-2 , Feminino , Humanos , Masculino , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Células Cultivadas , Cromossomos Humanos Par 21/genética , Bases de Dados Factuais , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Genômica , Haplótipos/genética , Inflamação/genética , Doenças Inflamatórias Intestinais/genética , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/patologia , Proteína Proto-Oncogênica c-ets-2/genética , Proteína Proto-Oncogênica c-ets-2/metabolismo , Reprodutibilidade dos Testes , Fatores de Necrose Tumoral/metabolismo , Interleucina-23/metabolismo
2.
Phys Rev Lett ; 132(4): 041001, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38335333

RESUMO

With excellent energy resolution and ultralow-level radiogenic backgrounds, the high-purity germanium detectors in the Majorana Demonstrator enable searches for several classes of exotic dark matter (DM) models. In this work, we report new experimental limits on keV-scale sterile neutrino DM via the transition magnetic moment from conversion to active neutrinos ν_{s}→ν_{a}. We report new limits on fermionic dark matter absorption (χ+A→ν+A) and sub-GeV DM-nucleus 3→2 scattering (χ+χ+A→ϕ+A), and new exclusion limits for bosonic dark matter (axionlike particles and dark photons). These searches utilize the (1-100)-keV low-energy region of a 37.5-kg y exposure collected by the Demonstrator between May 2016 and November 2019 using a set of ^{76}Ge-enriched detectors whose surface exposure time was carefully controlled, resulting in extremely low levels of cosmogenic activation.

3.
J Int Neuropsychol Soc ; 30(1): 27-34, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37154103

RESUMO

OBJECTIVE: Loneliness is a concern for patients with schizophrenia. However, the correlates of loneliness in patients with schizophrenia are unclear; thus, the aim of the study is to investigate neuro- and social cognitive mechanisms associated with loneliness in individuals with schizophrenia. METHOD: Data from clinical, neurocognitive, and social cognitive assessments were pooled from two cross-national samples (Poland/USA) to examine potential predictors of loneliness in 147 patients with schizophrenia and 103 healthy controls overall. Furthermore, the relationship between social cognition and loneliness was explored in clusters of patients with schizophrenia differing in social cognitive capacity. RESULTS: Patients reported higher levels of loneliness than healthy controls. Loneliness was linked to increased negative and affective symptoms in patients. A negative association between loneliness and mentalizing and emotion recognition abilities was found in the patients with social-cognitive impairments, but not in those who performed at normative levels. CONCLUSIONS: We have elucidated a novel mechanism which may explain previous inconsistent findings regarding the correlates of loneliness in individuals with schizophrenia.


Assuntos
Disfunção Cognitiva , Mentalização , Esquizofrenia , Teoria da Mente , Humanos , Esquizofrenia/complicações , Solidão , Emoções , Disfunção Cognitiva/complicações , Cognição , Percepção Social
4.
Phys Rev Lett ; 130(6): 062501, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36827565

RESUMO

The Majorana Demonstrator searched for neutrinoless double-ß decay (0νßß) of ^{76}Ge using modular arrays of high-purity Ge detectors operated in vacuum cryostats in a low-background shield. The arrays operated with up to 40.4 kg of detectors (27.2 kg enriched to ∼88% in ^{76}Ge). From these measurements, the Demonstrator has accumulated 64.5 kg yr of enriched active exposure. With a world-leading energy resolution of 2.52 keV FWHM at the 2039 keV Q_{ßß} (0.12%), we set a half-life limit of 0νßß in ^{76}Ge at T_{1/2}>8.3×10^{25} yr (90% C.L.). This provides a range of upper limits on m_{ßß} of (113-269) meV (90% C.L.), depending on the choice of nuclear matrix elements.

5.
Phys Rev Lett ; 130(5): 051803, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36800477

RESUMO

The COHERENT Collaboration searched for scalar dark matter particles produced at the Spallation Neutron Source with masses between 1 and 220 MeV/c^{2} using a CsI[Na] scintillation detector sensitive to nuclear recoils above 9 keV_{nr}. No evidence for dark matter is found and we thus place limits on allowed parameter space. With this low-threshold detector, we are sensitive to coherent elastic scattering between dark matter and nuclei. The cross section for this process is orders of magnitude higher than for other processes historically used for accelerator-based direct-detection searches so that our small, 14.6 kg detector significantly improves on past constraints. At peak sensitivity, we reject the flux consistent with the cosmologically observed dark-matter concentration for all coupling constants α_{D}<0.64, assuming a scalar dark-matter particle. We also calculate the sensitivity of future COHERENT detectors to dark-matter signals which will ambitiously test multiple dark-matter spin scenarios.

6.
Phys Rev Lett ; 131(15): 152501, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37897780

RESUMO

^{180m}Ta is a rare nuclear isomer whose decay has never been observed. Its remarkably long lifetime surpasses the half-lives of all other known ß and electron capture decays due to the large K-spin differences and small energy differences between the isomeric and lower-energy states. Detecting its decay presents a significant experimental challenge but could shed light on neutrino-induced nucleosynthesis mechanisms, the nature of dark matter, and K-spin violation. For this study, we repurposed the Majorana Demonstrator, an experimental search for the neutrinoless double-beta decay of ^{76}Ge using an array of high-purity germanium detectors, to search for the decay of ^{180m}Ta. More than 17 kg, the largest amount of tantalum metal ever used for such a search, was installed within the ultralow-background detector array. In this Letter, we present results from the first year of Ta data taking and provide an updated limit for the ^{180m}Ta half-life on the different decay channels. With new limits up to 1.5×10^{19} yr, we improved existing limits by 1-2 orders of magnitude which are the most sensitive searches for a single ß and electron capture decay ever achieved. Over all channels, the decay can be excluded for T_{1/2}<0.29×10^{18} yr.

8.
Phys Rev Lett ; 131(22): 221801, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38101357

RESUMO

Using an 185-kg NaI[Tl] array, COHERENT has measured the inclusive electron-neutrino charged-current cross section on ^{127}I with pion decay-at-rest neutrinos produced by the Spallation Neutron Source at Oak Ridge National Laboratory. Iodine is one the heaviest targets for which low-energy (≤50 MeV) inelastic neutrino-nucleus processes have been measured, and this is the first measurement of its inclusive cross section. After a five-year detector exposure, COHERENT reports a flux-averaged cross section for electron neutrinos of 9.2_{-1.8}^{+2.1}×10^{-40} cm^{2}. This corresponds to a value that is ∼41% lower than predicted using the MARLEY event generator with a measured Gamow-Teller strength distribution. In addition, the observed visible spectrum from charged-current scattering on ^{127}I has been measured between 10 and 55 MeV, and the exclusive zero-neutron and one-or-more-neutron emission cross sections are measured to be 5.2_{-3.1}^{+3.4}×10^{-40} and 2.2_{-0.5}^{+0.4}×10^{-40} cm^{2}, respectively.

9.
Diabet Med ; 40(8): e15088, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36929728

RESUMO

Older adults with diabetes may carry a substantial health burden in Western ageing societies, occupy more than one in four beds in care homes, and are a highly vulnerable group who often require complex nursing and medical care. The global pandemic (COVID-19) had its epicentre in care homes and revealed many shortfalls in diabetes care resulting in hospital admissions and considerable mortality and comorbid illness. The purpose of this work was to develop a national Strategic Document of Diabetes Care for Care Homes which would bring about worthwhile, sustainable and effective quality diabetes care improvements, and address the shortfalls in care provided. A large diverse and multidisciplinary group of stakeholders (NAPCHD) defined 11 areas of interest where recommendations were needed and using a subgroup allocation approach were set tasks to produce a set of primary recommendations. Each subgroup was given 5 starter questions to begin their work and a format to provide responses. During the initial phase, 16 key findings were identified. Overall, after a period of 18 months, 49 primary recommendations were made, and 7 major conclusions were drawn from these. A model of community and integrated diabetes care for care home residents with diabetes was proposed, and a series of 5 'quick-wins' were created to begin implementation of some of the recommendations that would not require significant funding. The work of the NAPCHD is ongoing but we hope that this current resource will help leaders to make these required changes happen.


Assuntos
COVID-19 , Diabetes Mellitus , Humanos , Idoso , COVID-19/epidemiologia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/terapia , Envelhecimento , Comorbidade
10.
Int J Colorectal Dis ; 38(1): 95, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37055632

RESUMO

PURPOSE: In Germany, colorectal robot-assisted surgery (RAS) has found its way and is currently used as primary technique in colorectal resections at our clinic. We investigated whether RAS can be extensively combined with enhanced recovery after surgery (ERAS®) in a large prospective patient group. METHODS: Using the DaVinci Xi surgical robot, all colorectal RAS from 09/2020 to 01/2022 were incorporated into our ERAS® program. Perioperative data were prospectively recorded using a data documentation system. The extent of resection, duration of the operation, intraoperative blood loss, conversion rate, and postoperative short-term results were analyzed. We documented the postoperative duration of Intermediate Care Unit (IMC) stay and major and minor complications according to the Clavien-Dindo classification, anastomotic leak rate, reoperation rate, hospital-stay length, and ERAS® guideline adherence. RESULTS: One hundred patients (65 colon and 35 rectal resections) were included (median age: 69 years). The median durations of surgery were 167 min (colon resection) and 246 min (rectal resection). Postoperatively, four patients were IMC-treated (median stay: 1 day). In 92.5% of the colon and 88.6% of the rectum resections, no or minor complications occurred postoperatively. The anastomotic leak rate was 3.1% in colon and 5.7% in rectal resection. The reoperation rate was 7.7% (colon resection) and 11.4% (rectal resection). The hospital stay length was 5 days (colon resection) and 6.5 days (rectal resection). The ERAS® guideline adherence rate was 88% (colon resection) and 82.6% (rectal resection). CONCLUSION: Patient perioperative therapy per the multimodal ERAS® concept is possible without any problems in colorectal RAS, leading to low morbidity and short hospital stays.


Assuntos
Neoplasias Colorretais , Laparoscopia , Procedimentos Cirúrgicos Robóticos , Robótica , Humanos , Idoso , Reto/cirurgia , Estudos Prospectivos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Fístula Anastomótica/etiologia , Fístula Anastomótica/cirurgia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Neoplasias Colorretais/cirurgia , Tempo de Internação , Laparoscopia/métodos
11.
Anim Biotechnol ; 34(4): 1686-1693, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34985376

RESUMO

Little is known about how varying the plane of nutrition before and after weaning can influence gene expression that drives mammary gland development (MGD). Therefore, the aim of this study was to investigate this paradigm in a seasonal sheep breed. Forty pre-weaning 30-day old Kurdish female lambs were fed either a low-nutrient and protein (L; 2.0 Mcal ME/kg DM; 8.70% crude protein [CP]) or high-nutrient and protein diet (H; 2.5 Mcal ME/kg DM; 14.80% CP). At d 120 (weaning), lambs were allocated into a 2 × 2 arrangement based on pre- and post-weaning diets, resulting in four groups (LL, LH, HL, HH). On d 210, mammary biopsy samples were taken for histomorphological and gene expression studies. Alveoli were larger in HH compared with all other groups (p < 0.05). Whilst estrogen receptor-alpha, progesterone receptor, growth hormone receptor and insulin-like growth factor binding protein-1 gene expression was modulated depending on pre- or post-weaning nutritional levels (p < 0.01). Overall, a consistent high plane of nutrition promoted MGD, with more a complex relationship evident between the expression of genes critical for mammary gland function and development. These findings provide scope for future tailored nutritional strategies to optimize both liveweight gain and MGD.


Assuntos
Dieta , Estado Nutricional , Animais , Feminino , Ovinos/genética , Expressão Gênica , Dieta/veterinária , Ração Animal/análise
12.
J Dairy Sci ; 106(8): 5452-5467, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37268581

RESUMO

Uptake of advice and the ability to facilitate change on-farm are key elements for successful veterinary practice. However, having the necessary clinical skills and knowledge is not enough to achieve this: effective communication skills are essential for veterinarians to realize their advisory role by exploring and understanding the farmer's worldview. Research of verbal aspects of veterinarian communication supports the use of a relationship-centered communication style; we next need to study how veterinarian-farmer nonverbal communication (NVC) can influence interactions and their outcomes, which has been examined in medical and companion animal practice. In this study, we considered which aspects of NVC should be measured, and how, to provide an essential first step toward understanding the significance of NVC for veterinarians working in dairy practice, which should be of interest to researchers, veterinary educators, and practitioners. Eleven video recordings of routine consultations in the UK were analyzed for farmer and veterinarian NVC. The NVC attributes with established links to positive patient and client outcomes from medical and social science studies were chosen, and a methodology developed for their measurement, by adapting measures typically used in NVC research. Each consultation was segmented into intervals defined by the main activity and location on farm: introduction, fertility examination, discussion, and closing. This approach allowed us to analyze the content more consistently, establish which aspects of NVC featured within each interval, and whether the activity and location influenced the observed NVC. We measured 12 NVC attributes, including body orientation, interpersonal distance, head position, and body lean, which have been shown to influence empathy, rapport, and trust: key components of relationship-centered communication. Future research should seek to establish the significance of NVC in effective communication between veterinarian and farmer, building on our findings that show it is possible to measure nonverbal attributes. Veterinarians may benefit from becoming skilled nonverbal communicators and have more effective conversations during routine consultations, motivating farmers to make changes and improve herd health.


Assuntos
Fazendeiros , Médicos Veterinários , Animais , Humanos , Indústria de Laticínios/métodos , Fazendas , Comunicação , Encaminhamento e Consulta
13.
Phys Rev Lett ; 129(8): 080401, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36053678

RESUMO

The Majorana Demonstrator neutrinoless double-beta decay experiment comprises a 44 kg (30 kg enriched in ^{76}Ge) array of p-type, point-contact germanium detectors. With its unprecedented energy resolution and ultralow backgrounds, Majorana also searches for rare event signatures from beyond standard model physics in the low energy region below 100 keV. In this Letter, we test the continuous spontaneous localization (CSL) model, one of the mathematically well-motivated wave function collapse models aimed at solving the long-standing unresolved quantum mechanical measurement problem. While the CSL predicts the existence of a detectable radiation signature in the x-ray domain, we find no evidence of such radiation in the 19-100 keV range in a 37.5 kg-y enriched germanium exposure collected between December 31, 2015, and November 27, 2019, with the Demonstrator. We explored both the non-mass-proportional (n-m-p) and the mass-proportional (m-p) versions of the CSL with two different assumptions: that only the quasifree electrons can emit the x-ray radiation and that the nucleus can coherently emit an amplified radiation. In all cases, we set the most stringent upper limit to date for the white CSL model on the collapse rate, λ, providing a factor of 40-100 improvement in sensitivity over comparable searches. Our limit is the most stringent for large parts of the allowed parameter space. If the result is interpreted in terms of the Diòsi-Penrose gravitational wave function collapse model, the lower bound with a 95% confidence level is almost an order of magnitude improvement over the previous best limit.

14.
Phys Rev Lett ; 129(8): 081801, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36053683

RESUMO

We measured the cross section of coherent elastic neutrino-nucleus scattering (CEvNS) using a CsI[Na] scintillating crystal in a high flux of neutrinos produced at the Spallation Neutron Source at Oak Ridge National Laboratory. New data collected before detector decommissioning have more than doubled the dataset since the first observation of CEvNS, achieved with this detector. Systematic uncertainties have also been reduced with an updated quenching model, allowing for improved precision. With these analysis improvements, the COHERENT Collaboration determined the cross section to be (165_{-25}^{+30})×10^{-40} cm^{2}, consistent with the standard model, giving the most precise measurement of CEvNS yet. The timing structure of the neutrino beam has been exploited to compare the CEvNS cross section from scattering of different neutrino flavors. This result places leading constraints on neutrino nonstandard interactions while testing lepton flavor universality and measures the weak mixing angle as sin^{2}θ_{W}=0.220_{-0.026}^{+0.028} at Q^{2}≈(50 MeV)^{2}.

15.
Phys Rev Lett ; 129(8): 081803, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36053699

RESUMO

Axions were originally proposed to explain the strong-CP problem in QCD. Through axion-photon coupling, the Sun could be a major source of axions, which could be measured in solid state detection experiments with enhancements due to coherent Primakoff-Bragg scattering. The Majorana Demonstrator experiment has searched for solar axions with a set of ^{76}Ge-enriched high purity germanium detectors using a 33 kg-yr exposure collected between January, 2017 and November, 2019. A temporal-energy analysis gives a new limit on the axion-photon coupling as g_{aγ}<1.45×10^{-9} GeV^{-1} (95% confidence level) for axions with mass up to 100 eV/c^{2}. This improves laboratory-based limits between about 1 eV/c^{2} and 100 eV/c^{2}.

16.
Clin Radiol ; 77(7): e509-e517, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35414431

RESUMO

AIM: To evaluate a novel deep-learning denoising method for ultra-low dose CT (ULDCT) in the assessment of coronary artery calcium score (CACS). MATERIALS AND METHODS: Sixty adult patients who underwent two unenhanced chest CT examinations, a normal dose CT (NDCT) and an ULDCT, were enrolled prospectively between September 2017 to December 201. A special training set was created to learn the characteristics of the real noise affecting the ULDCT implementing a fully convolutional neural network with batch normalisation. Subsequently, the 60 ULDCTs of the evaluation set were denoised. Two blinded radiologists assessed the NDCT, ULDCT, and denoised-ULDCT (DULDCT), assigning a CACS and categorised each scan as having a score above or below 100 and presence of calcifications (score 0 versus >0). Statistical analysis was used to evaluate the agreement between the readers and differences in CACSs between each imaging method. RESULTS: After excluding one patient, the cohort included 59 patients (median age 67 years, 58% men). The ULDCT median effective radiation dose (ERD) was 0.172 mSv, which was 2.8% of the NDCT median ERD. Denoising improved the signal-to-noise ratio by 27.7% (p<0.001). Interobserver agreement was almost perfect between readers (intraclass correlation coefficient >0.993). CACSs were lower for ULDCT and DULDCT as compared to the NDCT (p ≤ 0.001). In differentiating between the presence and absence of coronary artery calcifications, DULDCT showed greater accuracy (98-100%) and positive likelihood ratio (14.29->99) compared to ULDCT (92% and 2.78, respectively). CONCLUSION: DULCT significantly reduced the image noise and better identified patients with no coronary artery calcifications than native ULDCT.


Assuntos
Cálcio , Aprendizado Profundo , Adulto , Idoso , Vasos Coronários/diagnóstico por imagem , Feminino , Humanos , Pulmão , Masculino , Doses de Radiação , Tomografia Computadorizada por Raios X/métodos
17.
BMC Health Serv Res ; 22(1): 1210, 2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36171574

RESUMO

INTRODUCTION: Care for patients with chronic obstructive pulmonary disease (COPD) is provided by both family physicians (FP) and specialists. Ideally, patients receive comprehensive and coordinated care from this provider team. The objectives for this study were: 1) to describe the family and specialist physician network of care for Ontario patients newly diagnosed with COPD and 2) to determine the associations between selected characteristics of the physician network and unplanned healthcare utilization. METHODS: We conducted a retrospective cohort study using Ontario health administrative data housed at ICES (formerly the Institute for Clinical Evaluative Sciences). Ontario patients, ≥ 35 years, newly diagnosed with COPD were identified between 2005 and 2013. The FP and specialist network of care characteristics were described, and the relationship between selected characteristics (i.e., continuity of care) with unplanned healthcare utilization during the first 5 years after COPD diagnosis were determined in multivariate models. RESULTS: Our cohort consisted of 450,837 patients, mean age 61.5 (SD 14.6) years. The FP was the predominant provider of care for 86.4% of the patients. Using the Bice-Boxerman's Continuity of Care Index (COCI), a measure reflecting care across different providers, 227,082 (50.4%) were categorized in a low COCI group based on a median cut-off. In adjusted analyses, patients in the low COCI group were more likely to have a hospital admission (OR = 2.27, 95% CI 2.20,2.22), 30-day readmission (OR = 2.44, 95% CI 2.39, 2.49) and ER visit (OR = 2.27, 95% CI 2.25, 2.29). CONCLUSION: Higher indices of continuity of care are associated with reduced unplanned hospital use for patients with COPD. Primary care-based practice models to enhance continuity through coordination and integration of both primary and specialist care have the potential to enhance the health experience for patients with COPD and should be a health service planning priority.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Continuidade da Assistência ao Paciente , Hospitalização , Humanos , Pessoa de Meia-Idade , Readmissão do Paciente , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/terapia , Estudos Retrospectivos
18.
Dis Aquat Organ ; 150: 1-16, 2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35796507

RESUMO

The genera Paramoeba and Neoparamoeba (Amoebozoa, Dactylopodida, Paramoebidae) include well-known opportunistic pathogens associated with fish (N. peruans; amoebic gill disease), lobsters, molluscs and sea urchins, but only rarely with crabs (grey crab disease of blue crabs). Following reports of elevated post-capture mortality in edible crabs Cancer pagurus captured from a site within the English Channel fishery in the UK, a novel disease (amoebic crab disease, ACD) was detected in significant proportions of the catch. We present histopathological, transmission electron microscopy and molecular phylogenetic data, showing that this disease is defined by colonization of haemolymph, connective tissues and fixed phagocytes by amoeboid cells, leading to tissue destruction and presumably death in severely diseased hosts. The pathology was strongly associated with a novel amoeba with a phylogenetic position on 18S rRNA gene trees robustly sister to Janickina pigmentifera (which groups within the current circumscription of Paramoeba/Neoparamoeba), herein described as Janickina feisti n. sp. We provide evidence that J. feisti is associated with ACD in 50% of C. pagurus sampled from the mortality event. A diversity of other paramoebid sequence types, clustering with known radiations of N. pemaquidensis and N. aestuarina and a novel N. aestuarina sequence type, was detected by PCR in most of the crabs investigated, but their detection was much less strongly associated with clinical signs of disease. The discovery of ACD in edible crabs from the UK is discussed relative to published historical health surveys for this species.


Assuntos
Amebíase , Amoeba , Braquiúros , Neoplasias , Amebíase/veterinária , Animais , Neoplasias/veterinária , Filogenia , Reino Unido/epidemiologia
19.
J Dairy Sci ; 105(10): 8354-8363, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36055833

RESUMO

Johne's disease and bovine tuberculosis are diseases of economic, public health, and animal welfare importance. The single intradermal cervical comparative tuberculin (SICCT) test, which is used to determine bovine tuberculosis status as part of eradication schemes in the United Kingdom and some other countries, has been reported to interfere with the results of the widely used ELISA to detect antibodies against Mycobacterium avium ssp. paratuberculosis (MAP) in milk. Better understanding of the relationship between SICCT and MAP tests can improve management and control of Johne's disease. The aim of this study was to characterize the relationship between SICCT testing and milk ELISA performance and to assess whether the immunological response to the SICCT test is different for MAP-infected cows and noninfected cows. We used repeated MAP milk ELISA test results of a cohort of 805,561 cows in the United Kingdom between 2010 and 2018 that had milk ELISA tests within 90 d of SICCT testing to identify cows likely to be infected. We then assessed, separately, for cows deemed to be MAP-infected and noninfected, the association between MAP test results and proximity to SICCT testing by means of survival analysis and generalized additive mixed models. The results were used to quantify the effect SICCT testing may have on performance of milk ELISA tests conducted soon after SICCT testing. At high prevalence levels (20%) of MAP in the infected herd, overall accuracy of the milk ELISA is not reduced when testing occurs within 14 d from SICCT testing. Milk ELISA values of cows deemed to be infected were highest when MAP testing was closer in time to SICCT testing, suggesting the SICCT test enhances antibody response for MAP in infected cows. This corresponds to higher sensitivity of the MAP milk ELISA when testing within 30 d of the SICCT test. For cows deemed to be noninfected, the effect of previous SICCT testing was delayed compared with infected cows, with MAP milk ELISA values peaking at around 15 d post-SICCT testing. For both, MAP-infected and noninfected cows, interference from SICCT test diminished 30 d after SICCT testing, suggesting post 30 d to be the most appropriate time for evaluating the milk ELISA for MAP after SICCT testing. Our results provide strong evidence that the effect of the SICCT test on serological response against MAP is different for MAP-infected versus noninfected cows and that, as a result of this distinct effect, it is possible to improve interpretation of MAP milk ELISA test results (higher accuracy) by taking into consideration time since SICCT testing.


Assuntos
Doenças dos Bovinos , Mycobacterium avium subsp. paratuberculosis , Paratuberculose , Tuberculose Bovina , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Humanos , Leite/microbiologia , Paratuberculose/microbiologia , Tuberculina
20.
J Dairy Sci ; 105(9): 7373-7385, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35931484

RESUMO

Ruminal biohydrogenation (BH) of unsaturated fatty acids (FA) reduces absorption of essential FA and can result in formation of bioactive FA that cause milk fat depression. Rates of biohydrogenation of unsaturated FA are commonly observed using in vitro systems and are not well described in vivo. Seven ruminally cannulated cows were enrolled in a 3 × 3 Latin square design study to quantify biohydrogenation of 18:1n-9, 18:2n-6, and 18:3n-3 using a recently developed in vivo BH assay. All cows were fed a common high corn silage basal diet. Biohydrogenation was quantified using a perturbation model that consisted of a bolus dose of 200 g of an oil enriched in each unsaturated FA (oleic acid, OA = 87% 18:1n-9 sunflower oil; linoleic acid, LA = 70% 18:2n-6 safflower oil; and α-linolenic acid, ALA = 54% 18:3n-3 flaxseed oil) and 12 g of 17:0 as a marker of rumen outflow. Rumen contents were sampled before and after the bolus and enrichment of the bolused FA modeled. Using first-order kinetics to model FA disappearance, the fractional rates of disappearance of 18:1n-9 was 0.597 per hour, 18:2n-6 was 0.618 per hour, and 18:3n-3 was 0.834 per hour, similar to rates previously reported with this approach. Rumen turnover of 17:0 was 0.123 per hour, 0.065 per hour, and 0.106 per hour during the OA, LA, and ALA treatments, respectively. The extents of BH were calculated to be 82.8, 90.4, and 88.6% for 18:1n-9, 18:2n-6, and 18:3n-3, respectively. Finally, compartmental modeling was used to quantify the amount of each unsaturated FA metabolized through trans-10 and trans-11 BH pathways. The recently developed in vivo BH assay was able to predict rates of BH and provide insight into rumen metabolism of individual FA and may be useful to future investigations.


Assuntos
Rúmen , Ácido alfa-Linolênico , Animais , Bovinos , Dieta/veterinária , Ácidos Graxos/metabolismo , Ácidos Graxos Insaturados/metabolismo , Feminino , Hidrogenação , Lactação , Leite/metabolismo , Rúmen/metabolismo , Silagem , Ácido alfa-Linolênico/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA