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Brent Race Kimberly Meade-White Richard Race Bruce Chesebro 《Journal of virology》2009,83(18):9608-9610
Chronic wasting disease (CWD) is a neurodegenerative prion disease of cervids. Some animal prion diseases, such as bovine spongiform encephalopathy, can infect humans; however, human susceptibility to CWD is unknown. In ruminants, prion infectivity is found in central nervous system and lymphoid tissues, with smaller amounts in intestine and muscle. In mice, prion infectivity was recently detected in fat. Since ruminant fat is consumed by humans and fed to animals, we determined infectivity titers in fat from two CWD-infected deer. Deer fat devoid of muscle contained low levels of CWD infectivity and might be a risk factor for prion infection of other species.Prion diseases are fatal neurodegenerative diseases that include Creutzfeldt-Jakob disease in humans, bovine spongiform encephalopathy (BSE) in cattle, scrapie in sheep, and chronic wasting disease (CWD) in cervids. Cross-species prion infection can occur and is responsible for the spread of BSE to humans (2). Since spread is likely due to exposure to infected tissues, it is vital to know which tissues contain infectivity. In animals such as cattle, sheep, and cervids, whose tissues are part of both the human and domestic-animal food chains, the central nervous system (CNS) has the highest propensity for infectivity. Lymphoid organs and muscles can also be positive for the disease agent, but this varies among species (1, 4, 7). We recently found prion infectivity in brown and white fat of scrapie agent-infected mice (13) and wanted to determine if fat from animals actually consumed by humans may also carry infectivity. To answer this question, we inoculated fat from two CWD agent-infected deer into susceptible transgenic mice expressing deer prion protein (TgDeerPrP mouse) (10). 相似文献
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Daniela Meloni Katia Varello Marzia Pezzolato Elsa Manzardo Maria C Cavarretta Francesco Ingravalle Maria Caramelli Elena Bozzetta 《BMC research notes》2010,3(1):193
Background
Routine rapid testing for Bovine Spongiform Encephalopathy (BSE) has highlighted some problems with BSE rapid test performance, the most significant being the number of initially reactive samples and the false positive results on autolyzed tissue. This point is important for BSE active surveillance in risk populations, because tissue autolysis is often unavoidable in routine cases. A robust test suitable for use on field material is therefore needed. To date, very limited information regarding the effect of autolysis on the robustness of rapid tests has been documented; therefore, the National Reference Centre for Animal Encephalopathies (CEA) rapid test laboratory selected 450 autolyzed and negative brain stem samples from fallen stock bovines older than 24 months to assess the specificity of four tests approved for BSE active surveillance: Biorad TeSeE, Enfer TSE version 2.0, Prionics® Check LIA, and IDEXX Herd Check BSE Antigen Kit EIA. The samples were graded according to the degree of autolysis and then dissected into five portions, four of which randomly assigned to processing by rapid tests and one to be available for confirmatory Western blot analysis.Findings
The specificity of the four systems was 100% for all three grades of autolysis, while the percentage of initially reactive results was 0.00 (95%CI 0.00-0.82), 0.22 (95%CI 0.006-1.23), 0.44 (95%CI 0.05-1.60), and 0.89 (95%CI 0.24-2.26) for the Biorad TeSeE, the Prionics® Check LIA, the IDEXX Herd Check BSE and the Enfer TSE tests, respectively. No association with the degree of autolysis could be drawn.Conclusions
The present study demonstrates that the four rapid tests can be considered well-running diagnostic tools regardless of tissue quality; nevertheless, the number of initial reactive samples reported for some systems must not be underestimated in routine testing.Furthermore the compliance with the reported performance can be guaranteed only when an ongoing high careful batch quality control system is in place.4.
Background
In many of the European countries affected by Bovine Spongiform Encephalopathy (BSE), case clustering patterns have been observed. Most of these patterns have been interpreted in terms of heterogeneities in exposure of cattle to the BSE agent. Here we investigate whether spatial clustering is present in the Dutch BSE case data.Results
We have found three spatial case clusters in the Dutch BSE epidemic. The clusters are geographically distinct and each cluster appears in a different birth cohort. When testing all birth cohorts together, only one significant cluster was detected. The fact that we found stronger spatial clustering when using a cohort-based analysis, is consistent with the evidence that most BSE infections occur in animals less than 12 or 18 months old.Conclusion
Significant spatial case clustering is present in the Dutch BSE epidemic. The spatial clusters of BSE cases are most likely due to time-dependent heterogeneities in exposure related to feed production.5.
Lili Wei Leixi Cao Yanyan Miao Shuju Wu Shumei Xu Ruisheng Wang Jun Du Aihua Liang Yuejun Fu 《Biotechnology letters》2017,39(8):1129-1139
6.
Kerry A Woodbine Graham F Medley Stephen J Moore Ana Ramirez-Villaescusa Sam Mason Laura E Green 《BMC veterinary research》2008,4(1):35
Background
Neosporosis caused by the protozoan parasite Neospora caninum, is an economically important cause of abortion, stillbirth, low milk yield, reduced weight gain and premature culling in cattle. Consequently, a seroepidemiological study of N. caninum antibodies was conducted in England with 29,782 samples of blood taken from 15,736 cattle from 114 herds visited on three occasions at yearly intervals. Herds were categorised into lower (< 10%) and higher (≥ 10%) median herd seroprevalence. Hierarchical models were run to investigate associations between the sample to positive (S/P) ratio and herd and cattle factors.Results
Ninety-four percent of herds had at least one seropositive cow; 12.9% of adult cattle had at least one seropositive test. Approximately 90% of herds were seropositive at all visits; 9 herds (8%) changed serological status between visits. The median N. caninum seroprevalence in positive herds was 10% (range 0.4% to 58.8%). There was a positive association between the serostatus of offspring and dams that were ever seropositive. In the hierarchical model of low seroprevalence herds there was no significant association between S/P ratio and cattle age. There was a significantly lower S/P ratio in cattle in herds that were totally restocked after the foot-and-mouth epidemic of 2001 compared with those from continuously stocked herds and cattle purchased into these herds had a higher S/P ratio than homebred cattle. In the model of high seroprevalence herds the S/P ratio increased with cattle age, but was not associated with restocking or cattle origin.Conclusion
There were no strong temporal changes in herd seroprevalence of N. caninum but 90% of herds had some seropositive cattle over this time period. Vertical transmission from seropositive dams appeared to occur in all herds. In herds with a high seroprevalence the increasing S/P ratio in 2–4 year old cattle is suggestive of exposure to N. caninum: horizontal transmission between adult cattle, infection from a local source or recrudescence and abortions. Between-herd movements of infected cattle enhance the spread of N. caninum, particularly into low seroprevalence herds. Some restocked herds had little exposure to N. caninum, while in others infection had spread in the time since restocking.7.
Saif Eddine Djemal Mariam Siala Salma Smaoui Sana Kammoun Chema Marouane Javier Bezos Feriele Messadi-Akrout Beatriz Romero Radhouane Gdoura 《BMC veterinary research》2017,13(1):393
Background
The genetic diversity of M. bovis in Tunisia is still underestimated despite the implementation of an eradication program. The lack of data about spatial distribution of the M. bovis population hinders the control of bovine tuberculosis (bTB) progress. This study represents the largest molecular analysis of M. bovis isolates in Tunisia. It is aimed to upgrade the understanding of bTB epidemiology and the geographical distribution of the infection. Tuberculosis research was performed in cattle (n?=?149) with TB-compatible lesions collected over 5 months from a slaughterhouse located in Sfax, Tunisia.Results
Ninety-four animals were found to be infected by M. bovis and two others by M. caprae. Spoligotyping revealed twenty-five patterns, SB0120, SB0134, and SB0121 being the most prevalent profiles (36.4%, 11.4%, and 7.2%, respectively). Three new spoligotypes were detected: SB2345, SB2344 and SB2343. MIRU-VNTR analysis classified the isolates in seventy-three profiles and showed a large genotypic variety observed within the main spoligotype which was split into several MIRU-VNTR types: 29 in SB0120 (h?=?0.983), 10 in SB0134 (h?=?0.981) and 7 in SB0121 (h?=?1). Genotyping revealed a common pattern in different geographic regions. It also showed that Sfax, located in southern-Tunisia, represents a high-risk area with an elevated genetic diversity.Conclusions
Spatial analysis may provide insights into disease transmission, which affects the effectiveness of eradication campaigns in cattle.8.
Marie GB Hansen Mette Christoffersen Line R Thuesen Morten R Petersen Anders M Bojesen 《Acta veterinaria Scandinavica》2010,52(1):3
Background
Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum are able to infect horses. However, the extend to which Danish horses are infected and seroconvert due to these two bacteria is unknown. The aim of the present study was to evaluate the seroprevalence of B. burgdorferi sensu lato and A. phagocytophilum in Danish horses.Methods
A total of 390 blood samples collected from all major regions of Denmark and with a geographical distribution corresponding to the density of the Danish horse population were analyzed. All samples were examined for the presence of antibodies against B. burgdorferi sensu lato and A. phagocytophilum by the use of the SNAP®4DX ® ELISA test.Results
Overall, 29.0% of the horses were seropositive for B. burgdorferi sensu lato whereas 22.3% were seropositive for A. phagocytophilum.Conclusions
Antibodies against B burgdorferi sensu lato and A. phagocytophilum are commonly found among Danish horses thus showing that Danish horses are frequently infected by these organisms.9.
Brooke A. Clemmons Robert I. Mihelic Ronique C. Beckford Joshua B. Powers Emily A. Melchior Zachary D. McFarlane Emily R. Cope Mallory M. Embree J. Travis Mulliniks Shawn R. Campagna Brynn H. Voy Phillip R. Myer 《Metabolomics : Official journal of the Metabolomic Society》2017,13(12):147
Introduction
Improving feed utilization in cattle is required to reduce input costs, increase production, and ultimately improve sustainability of the beef cattle industry. Characterizing metabolic differences between efficient and non-efficient animals will allow stakeholders to identify more efficient cattle during backgrounding.Objectives
This study used an untargeted metabolomics approach to determine differences in serum metabolites between animals of low and high residual feed intake.Methods
Residual feed intake was determined for 50 purebred Angus steers and 29 steers were selected for the study steers based on low versus high feed efficiency. Blood samples were collected from steers and analyzed using untargeted metabolomics via mass spectrometry. Metabolite data was analyzed using Metaboanalyst, visualized using orthogonal partial least squares discriminant analysis, and p-values derived from permutation testing. Non-esterified fatty acids, urea nitrogen, and glucose were measured using commercially available calorimetric assay kits. Differences in metabolites measured were grouped by residual feed intake was measured using one-way analysis of variance in SAS 9.4.Results
Four metabolites were found to be associated with differences in feed efficiency. No differences were found in other serum metabolites, including serum urea nitrogen, non-esterified fatty acids, and glucose.Conclusions
Four metabolites that differed between low and high residual feed intake have important functions related to nutrient utilization, among other functions, in cattle. This information will allow identification of more efficient steers during backgrounding.10.
Leandro Tana-Hernández Katherine Navarrete-Arroyo Jorge Ron-Román Armando Reyna-Bello María Augusta Chávez-Larrea 《BMC veterinary research》2017,13(1):392
Background
Bovine anaplasmosis is an endemic disease in tropical and subtropical areas. It is caused by a bacterium named Anaplasma marginale, and represents an economic problem for cattle farmers due to the losses it generates, such as: mortalities, reduced production, quarantine measures, treatments and control of vectors. The method most often used to diagnose this haemotrophic bacterium is direct examination on blood smear, which sensitivity and specificity are limited compared to other methods such as PCR. The present study aimed at investigating the presence of A. marginale in dairy cattle of Luz de América commune, province of Santo Domingo de los Tsachilas. Two PCRs were used to amplify specific regions of the Rickettsia for its molecular identification.Results
At first, 151 blood samples were tested: msp5 specific gene of A. marginale was identified in 130 samples, meaning 86.1% of them were infected by the rickettsia. Two positive samples were further randomly selected to confirm the presence of A. marginale through amplification, cloning and sequencing of the conserved region of gene 16S rRNA. The analysis of sequences obtained through cloning revealed a 100% identity between both samples and those registered in GenBank for A. marginale.Conclusion
This is the first report and molecular identification of A. marginale in the bovine population of Ecuador and its prevalence was high at the level of farms and animals. These results demonstrate the importance of proceeding to evaluate and characterize bovine Anaplasmosis in Ecuador in order to establish control measures and reduce their impact.11.
Rapid detection of infectious bovine Rhinotracheitis virus using recombinase polymerase amplification assays 总被引:2,自引:0,他引:2
Background
Infectious bovine rhinotracheitis virus (IBRV) is a major pathogen in cattle and has led to significant economic losses to the dairy industry worldwide, and therefore a more optimal method for the rapid diagnosis of IBRV infection is highly needed. In this study, we described the development of a lateral flow dipstrip (LFD) of isothermal recombinase polymerase amplification (RPA) method for rapid detection of IBRV.Methods
Distinct regions were selected as a candidate target for designing the LFD-RPA primers and probes. The analytical sensitivity of the RPA assay was determined using ten-fold serially diluted IBRV DNA. The specificity of the assay was assessed with other viral pathogens of cattle with similar clinic and other herpesviruses. The clinical performance was evaluated by testing 106 acute-phase high fever clinical specimens.Results
RPA primers and probe were designed to target the specific conserved UL52 region fragment of IBRV. The detection could be completed at a constant temperature of 38 °C for 25 min, and the amplification products were easily visualized on a simple LFD. The detection limit of this assay was 5 copies per reaction of IBRV DNA and there was no cross-reactivity with other viruses causing bovine gastrointestinal and respiratory infections or other herpesviruses. The assay performance on acute-phase high fever clinical samples collected from cattle with no vaccine against IBRV, which were suspected to be infected with IBRV, was validated by detecting 24 fecal, 36 blood, 38 nasal swab and 8 tissue specimens, and compared with SYBR Green I based real-time PCR. The coincidence between IBRV LFD-RPA and real-time PCR was 100%.Conclusion
IBRV LFD-RPA was fast and much easier to serve as an alternative to the common measures used for IBRV diagnosis, as there is reduction in the use of instruments for identification of the infected animals. In addition, this assay may be the potential candidate to be used as point-of-care diagnostics in the field.12.
Background
Bovine spongiform encephalopathy (BSE) is a transmissible spongiform encephalopathy (TSE) of cattle. Classical BSE is associated with ingestion of BSE-contaminated feedstuffs. H- and L-type BSE, collectively known as atypical BSE, differ from classical BSE by displaying a different disease phenotype and they have not been linked to the consumption of contaminated feed. Interestingly, the 2006 US H-type atypical BSE animal had a polymorphism at codon 211 of the bovine prion gene resulting in a glutamic acid to lysine substitution (E211K). This substitution is analogous a human polymorphism associated with the most prevalent form of heritable TSE in humans, and it is considered to have caused BSE in the 2006 US atypical BSE animal. In order to determine if this amino acid change is a heritable trait in cattle, we sequenced the prion alleles of the only known offspring of this animal, a 2-year-old heifer.Principal Findings
Sequence analysis revealed that both the 2006 US atypical BSE animal and its 2-year-old heifer were heterozygous at bovine prion gene nucleotides 631 through 633 for GAA (glutamic acid) and AAA (lysine). Both animals carry the E211K polymorphism, indicating that the allele is heritable and may persist within the cattle population.Conclusions
This is the first evidence that the E211K polymorphism is a germline polymorphism, not a somatic mutation, suggesting BSE may be transmitted genetically in cattle. In the event that E211K proves to result in a genetic form of BSE, this would be the first indication that all 3 etiologic forms of TSEs (spontaneous, hereditary, and infectious) are present in a non-human species. Atypical BSE arising as both genetic and spontaneous disease, in the context of reports that at least some forms of atypical BSE can convert to classical BSE in mice, suggests a cattle origin for classical BSE. 相似文献13.
Background
Hepatitis B infection caused by the hepatitis B virus is one of the most serious viral infections and a global health problem. In the transmission of hepatitis B infection, three different phases, i.e. acute infected, chronically infected, and carrier individuals, play important roles. Carrier individuals are especially significant, because they do not exhibit any symptoms and are able to transmit the infection. Here we assessed the transmissibility associated with different infection stages of hepatitis B and generated an epidemic model.Methods
To demonstrate the transmission dynamic of hepatitis B, we investigate an epidemic model by dividing the infectious class into three subclasses, namely acute infected, chronically infected, and carrier individuals with both horizontal and vertical transmission.Results
Numerical results and sensitivity analysis of some important parameters are presented to show that the proportion of births without successful vaccination, perinatally infected individuals, and direct contact rate are highest risk factors for the spread of hepatitis B in the community.Conclusion
Our work provides a coherent platform for studying the full dynamics of hepatitis B and an effective direction for theoretical work.14.
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Judy Orikiiriza Izabella Surowiec Elisabeth Lindquist Mari Bonde Jimmy Magambo Charles Muhinda Sven Bergström Johan Trygg Johan Normark 《Metabolomics : Official journal of the Metabolomic Society》2017,13(4):41
Introduction
Several studies have observed serum lipid changes during malaria infection in humans. All of them were focused at analysis of lipoproteins, not specific lipid molecules. The aim of our study was to identify novel patterns of lipid species in malaria infected patients using lipidomics profiling, to enhance diagnosis of malaria and to evaluate biochemical pathways activated during parasite infection.Methods
Using a multivariate characterization approach, 60 samples were representatively selected, 20 from each category (mild, severe and controls) of the 690 study participants between age of 0.5–6 years. Lipids from patient’s plasma were extracted with chloroform/methanol mixture and subjected to lipid profiling with application of the LCMS-QTOF method.Results
We observed a structured plasma lipid response among the malaria-infected patients as compared to healthy controls, demonstrated by higher levels of a majority of plasma lipids with the exception of even-chain length lysophosphatidylcholines and triglycerides with lower mass and higher saturation of the fatty acid chains. An inverse lipid profile relationship was observed when plasma lipids were correlated to parasitaemia.Conclusions
This study demonstrates how mapping the full physiological lipid response in plasma from malaria-infected individuals can be used to understand biochemical processes during infection. It also gives insights to how the levels of these molecules relate to acute immune responses.16.
Korey J. Brownstein Mahmoud Gargouri William R. Folk David R. Gang 《Metabolomics : Official journal of the Metabolomic Society》2017,13(11):133
Introduction
Botanicals containing iridoid and phenylethanoid/phenylpropanoid glycosides are used worldwide for the treatment of inflammatory musculoskeletal conditions that are primary causes of human years lived with disability, such as arthritis and lower back pain.Objectives
We report the analysis of candidate anti-inflammatory metabolites of several endemic Scrophularia species and Verbascum thapsus used medicinally by peoples of North America.Methods
Leaves, stems, and roots were analyzed by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) and partial least squares-discriminant analysis (PLS-DA) was performed in MetaboAnalyst 3.0 after processing the datasets in Progenesis QI.Results
Comparison of the datasets revealed significant and differential accumulation of iridoid and phenylethanoid/phenylpropanoid glycosides in the tissues of the endemic Scrophularia species and Verbascum thapsus.Conclusions
Our investigation identified several species of pharmacological interest as good sources for harpagoside and other important anti-inflammatory metabolites.17.
Nadine Strehmel David Strunk Veronika Strehmel 《Metabolomics : Official journal of the Metabolomic Society》2017,13(11):135
Introduction
Aqueous–methanol mixtures have successfully been applied to extract a broad range of metabolites from plant tissue. However, a certain amount of material remains insoluble.Objectives
To enlarge the metabolic compendium, two ionic liquids were selected to extract the methanol insoluble part of trunk from Betula pendula.Methods
The extracted compounds were analyzed by LC/MS and GC/MS.Results
The results show that 1-butyl-3-methylimidazolium acetate (IL-Ac) predominantly resulted in fatty acids, whereas 1-ethyl-3-methylimidazolium tosylate (IL-Tos) mostly yielded phenolic structures. Interestingly, bark yielded more ionic liquid soluble metabolites compared to interior wood.Conclusion
From this one can conclude that the application of ionic liquids may expand the metabolic snapshot.18.
Background
Campylobacteriosis is a zoonotic disease, and animals such as poultry, pigs and cattle may act as reservoirs for Campylobacter spp. Cattle shed Campylobacter spp. into the environment and they can act as a reservoir for human infection directly via contact with cattle or their faeces or indirectly by consumption of contaminated food. The aim of this study was to determine the prevalence, the quantitative load and the genetic strain diversity of Campylobacter spp. in dairy cattle of different age groups.Results
Faecal samples of 200 dairy cattle from three farms in the central part of Lithuania were collected and examined for Campylobacter. Cattle herds of all three farms were Campylobacter spp. positive, with a prevalence ranging from 75% (farm I), 77.5% (farm II) to 83.3% (farm III). Overall, the highest prevalence was detected in calves (86.5%) and heifers (86.2%). In contrast, the lowest Campylobacter prevalence was detectable in dairy cows (60.6%). C. jejuni, C. coli, C. lari and C. fetus subsp. fetus were identified in faecal samples of dairy cattle. C. upsaliensis was not detectable in any sample. The high counts of Campylobacter spp. were observed in faecal material of dairy cattle (average 4.5 log10 cfu/g). The highest numbers of Campylobacter spp. were found in faecal samples from calves (average 5.3 log10 cfu/g), whereas, faecal samples from cows harboured the lowest number of Campylobacter spp. (average 3.7 log10 cfu/g). Genotyping by fla A PCR-RFLP analysis of selected C. jejuni isolates showed that some genotypes were present in all farms and all age groups. However, farm or age specific genotypes were also identified.Conclusions
Future studies are needed to investigate risk factors related to the degree of colonisation in cattle. Based on that, possible measures to reduce the colonisation and subsequent shedding of Campylobacter in cattle could be established. It is important to further investigate the epidemiology of Campylobacter in the cattle population in order to assess associated risks to public health.19.
Daniel Cañueto Josep Gómez Reza M. Salek Xavier Correig Nicolau Cañellas 《Metabolomics : Official journal of the Metabolomic Society》2018,14(3):24
Introduction
Adoption of automatic profiling tools for 1H-NMR-based metabolomic studies still lags behind other approaches in the absence of the flexibility and interactivity necessary to adapt to the properties of study data sets of complex matrices.Objectives
To provide an open source tool that fully integrates these needs and enables the reproducibility of the profiling process.Methods
rDolphin incorporates novel techniques to optimize exploratory analysis, metabolite identification, and validation of profiling output quality.Results
The information and quality achieved in two public datasets of complex matrices are maximized.Conclusion
rDolphin is an open-source R package (http://github.com/danielcanueto/rDolphin) able to provide the best balance between accuracy, reproducibility and ease of use.20.
Zichen?Yang Jian?Sun Xiaofeng?Yang Zhiyuan?Zhang Bangwei?Lou Jian?Xiong Hermann?J?Schluesener Zhiren?Zhang