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41.
Jo Moore Stephen AC Hawkins Anthony R Austin Timm Konold Robert B Green Ian W Blamire Ian Dexter Michael J Stack Melanie J Chaplin Jan PM Langeveld Marion M Simmons Yvonne I Spencer Paul R Webb Michael Dawson Gerald AH Wells 《BMC research notes》2011,4(1):1-13
Background
Escherichia coli O157:H7 is the most common serovar of enterohemorrhagic E. coli associated with serious human disease outbreaks. Cattle are the main reservoir with E. coli O157:H7 inducing hemorrhagic enteritis in persistent shedding beef cattle, however little is known about how this pathogen affects cattle health. Jejunal Hemorrhage Syndrome (JHS) has unclear etiology but the pathology is similar to that described for E. coli O157:H7 challenged beef cattle suggestive that E. coli O157:H7 could be involved. There are no effective treatments for JHS however new approaches to managing pathogen issues in livestock using prebiotics and probiotics are gaining support. The first objective of the current study was to characterize pathogen colonization in hemorrhaged jejunum of dairy cattle during natural JHS outbreaks. The second objective was to confirm the association of mycotoxigenic fungi in feeds with the development of JHS and also to identify the presence of potential mycotoxins. The third objective was to determine the impact of a prebiotic, Celmanax?, or probiotic, Dairyman's Choice? paste, on the cytotoxicity associated with feed extracts in vitro. The fourth objective was to determine the impact of a prebiotic or a probiotic on E. coli O157:H7 colonization of mucosal explants and a bovine colonic cell line in vitro. The final objective was to determine if prebiotic and probiotic feed additives could modify the symptoms that preceded JHS losses and the development of new JHS cases.Findings
Dairy cattle developed JHS after consuming feed containing several types of mycotoxigenic fungi including Fusarium culmorum, F. poae, F. verticillioides, F. sporotrichioides, Aspergillus flavus, Penicillium roqueforti, P. crustosum, P. paneum and P. citrinum. Mixtures of Shiga toxin - producing Escherichia coli (STEC) colonized the mucosa in the hemorrhaged tissues of the cattle and no other pathogen was identified. The STECs expressed Stx1 and Stx2, but more significantly, Stxs were also present in the blood clot blocking the jejunum. Mycotoxin analysis of the corn crop confirmed the presence of fumonisin, NIV, ZEAR, DON, 15-ADON, 3-ADON, NEO, DAS, HT-2 and T-2. Feed extracts were toxic to enterocytes and 0.1% Celmanax? removed the cytotoxicity in vitro. There was no effect of Dairyman's Choice? paste on feed-extract activity in vitro. Fumonisin, T-2, ZEAR and DON were toxic to bovine cells and 0.1% Celmanax? removed the cytotoxicity in vitro. Celmanax? also directly decreased E. coli O157:H7 colonization of mucosal explants and a colonic cell line in a dose-dependent manner. There was no effect of Dairyman's Choice? paste on E. coli O157:H7 colonization in vitro. The inclusion of the prebiotic and probiotic in the feed was associated with a decline in disease.Conclusion
The current study confirmed an association between mycotoxigenic fungi in the feed and the development of JHS in cattle. This association was further expanded to include mycotoxins in the feed and mixtures of STECs colonizing the severely hemorrhaged tissues. Future studies should examine the extent of involvement of the different STEC in the infection process. The prebiotic, Celmanax?, acted as an anti-adhesive for STEC colonization and a mycotoxin binder in vitro. Future studies should determine the extent of involvement of the prebiotic in altering disease. 相似文献42.
Geraldine AC Lim Erica G Jewell Xi Li Timothy A Erwin Christopher Love Jacqueline Batley German Spangenberg David Edwards 《BMC plant biology》2007,7(1):40
Background
Molecular genetic maps provide a means to link heritable traits with underlying genome sequence variation. Several genetic maps have been constructed for Brassica species, yet to date, there has been no simple means to compare this information or to associate mapped traits with the genome sequence of the related model plant, Arabidopsis. 相似文献43.
Cloning and analysis of non-specific cytotoxic cell receptor (NCCRP)-1 from common carp Cyprinus carpio L 总被引:1,自引:0,他引:1
Sakata H Savan R Sogabe R Kono T Taniguchi K Gunimaladevi I Tassakka AC Sakai M 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2005,140(3-4):287-294
Nonspecific cytotoxic cell receptor protein (NCCRP-1) provides an important function in target cell recognition and activation of cytotoxicity. NCCRP-1 has been cloned from common carp Cyprinus carpio L. from fish barbel by EST analysis. The isolated gene is composed of 945 bp with a 79 bp 5' UTR, 714 bp open reading frame and 152 bp 3' UTR. The predicted NCCRP-1 gene is composed of 237 amino acid residues and its predicted signal peptide is 19 amino acid residues in length. This gene has conservation of all the related domains characteristic to the NCCRP-1 gene in fish. Phylogenetic and genomic analyses showed that carp NCCRP-1 was similar to other fish orthologues. The expression of NCCRP-1 gene was constitutive in both lymphoid and non-lymphoid tissues. Furthermore, by semi-quantitative RT-PCR studies, we showed that NCCRP-1 gene expression is increased in anterior kidney challenged with Aeromonas hydrophila. 相似文献
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46.
Christophe Rodriguez Cathia Soulié Anne-Geneviève Marcelin Vincent Calvez Diane Descamps Charlotte Charpentier Philippe Flandre Patricia Recordon-Pinson Pantxika Bellecave Jean-Michel Pawlotsky Bernard Masquelier the ANRS AC Study Group 《PloS one》2015,10(6)
Background
Maraviroc is an HIV entry inhibitor that alters the conformation of CCR5 and is poorly efficient in patients infected by viruses that use CXCR4 as an entry coreceptor. The goal of this study was to assess the capacity of ultra-deep pyrosequencing (UDPS) and different data analysis approaches to characterize HIV tropism at baseline and predict the therapeutic outcome on maraviroc treatment.Methods
113 patients with detectable HIV-1 RNA on HAART were treated with maraviroc. The virological response was assessed at months 1, 3 and 6. The sequence of the HIV V3 loop was determined at baseline and prediction of maraviroc response by different software and interpretation algorithms was analyzed.Results
UDPS followed by analysis with the Pyrotrop software or geno2pheno algorithm provided better prediction of the response to maraviroc than Sanger sequencing. We also found that the H34Y/S substitution in the V3 loop was the strongest individual predictor of maraviroc response, stronger than substitutions at positions 11 or 25 classically used in interpretation algorithms.Conclusions
UDPS is a powerful tool that can be used with confidence to predict maraviroc response in HIV-1-infected patients. Improvement of the predictive value of interpretation algorithms is possible and our results suggest that adding the H34S/Y substitution would substantially improve the performance of the 11/25/charge rule. 相似文献47.
Geraint B Rogers Leah Cuthbertson Lucas R Hoffman Peter AC Wing Christopher Pope Danny A P Hooftman Andrew K Lilley Anna Oliver Mary P Carroll Kenneth D Bruce Christopher J van der Gast 《The ISME journal》2013,7(4):697-706
High-throughput pyrosequencing and quantitative PCR (Q-PCR) analysis offer greatly improved accuracy and depth of characterisation of lower respiratory infections. However, such approaches suffer from an inability to distinguish between DNA derived from viable and non-viable bacteria. This discrimination represents an important step in characterising microbial communities, particularly in contexts with poor clearance of material or high antimicrobial stress, as non-viable bacteria and extracellular DNA can contribute significantly to analyses. Pre-treatment of samples with propidium monoazide (PMA) is an effective approach to non-viable cell exclusion (NVCE). However, the impact of NVCE on microbial community characteristics (abundance, diversity, composition and structure) is not known. Here, adult cystic fibrosis (CF) sputum samples were used as a paradigm. The effects of PMA treatment on CF sputum bacterial community characteristics, as analysed by pyrosequencing and enumeration by species-specific (Pseudomonas aeruginosa) and total bacterial Q-PCR, were assessed. At the local community level, abundances of both total bacteria and of P. aeruginosa were significantly lower in PMA-treated sample portions. Meta-analysis indicated no overall significant differences in diversity; however, PMA treatment resulted in a significant alteration in local community membership in all cases. In contrast, at the metacommunity level, PMA treatment resulted in an increase in community evenness, driven by an increase in diversity, predominately representing rare community members. Importantly, PMA treatment facilitated the detection of both recognised and emerging CF pathogens, significantly influencing ‘core'' and ‘satellite'' taxa group membership. Our findings suggest failure to implement NVCE may result in skewed bacterial community analyses. 相似文献
48.
Jennie Ursum Wouter H Bos Rob J van de Stadt Ben AC Dijkmans Dirkjan van Schaardenburg 《Arthritis research & therapy》2009,11(3):R75-6
Introduction
The aim of this study was to examine seroconversion and the relationship with age and inflammation of autoantibodies in a large group of patients attending an outpatient rheumatology clinic. 相似文献49.
This report describes a lysozyme expressed at high levels in the stomach of
the hoatzin, the only known foregut-fermenting bird. Evolutionary
comparison places it among the calcium-binding lysozymes rather than among
the conventional types. Conventional lysozymes were recruited as digestive
enzymes twice in the evolution of mammalian foregut fermenters, and these
independently recruited lysozymes share convergent structural changes
attributed to selective pressures in the stomach. Biochemical convergence
and parallel amino acid replacements are observed in the hoatzin stomach
lysozyme even though it has a different genetic origin from the mammalian
examples and has undergone more than 300 million years of independent
evolution.
相似文献
50.
Hennie G Raterman Alexandre E Voskuyl Ben AC Dijkmans Michael T Nurmohamed 《Arthritis research & therapy》2009,11(5):413-2
With great interest, we read the article by Toms and colleagues [1] in the previous issue of Arthritis Research & Therapy, in which they assessed prevalences of metabolic syndrome (MetS) in rheumatoid arthritis (RA) patients. Moreover, they identified demographic and clinical factors that may be associated with MetS. Toms and colleagues found prevalences of up to 45% of MetS and demonstrated older age and health status (health assessment questionnaire) to be associated with MetS irrespectively of the definition used. Of most interest, an association between methotrexate (MTX) use and decreased presence of MetS was observed in patients more than 60 years of age. The investigators hypothesized that this may be attributed to a drug-specific effect (and not to an anti-inflammatory effect) either by changing levels of adenosine, which is known to interact with glucose and lipid metabolism, or by an indirect effect mediated through concomitant folic acid administration, thereby decreasing homocysteine levels.Recently, we also examined the prevalence of MetS in (a subgroup of) RA patients in the CARRÉ investigation, a prospective cohort study on prevalent and incident cardiovascular disease and its underlying cardiovascular risk factors [2]. The findings of Toms and colleagues stimulated us to perform additional analyses in our total study population (n = 353).The prevalences of MetS were 35% and 25% (Table (Table1)1) according to criteria of National Cholesterol Education Program (NCEP) 2004 and NCEP 2001, respectively. In multivariate backward regression analyses, we found significant associations between body mass index, pulse rate, creatinine levels, hypothyroidism and diabetes mellitus and the presence of MetS independently of the criteria used (Table (Table2).2). However, an independent association between single use of MTX or use of MTX in combination with other disease-modifying antirheumatic drugs, on the one hand, and a decreased prevalence of MetS, on the other hand, could not be demonstrated (even in the subgroup of patients over the age of 60).
Open in a separate windowaMetabolic syndrome (MetS) according to National Cholesterol Education Program (NCEP) 2001; bMetS according to NCEP 2004. Continuous variables are presented as means (± standard deviations) in cases of normal distribution or as medians (interquartile ranges) in cases of non-normal distribution. BMI, body mass index; CRP, C-reactive protein; DAS28, disease activity score using 28 joint counts; DMARD, disease-modifying antirheumatic drug; ESR, erythrocyte sedimentation rate; HCQ, hydroxychloroquine; MTX, methotrexate; RA, rheumatoid arthritis; SSZ, sulfasalazine; TNF, tumour necrosis factor.
Open in a separate windowaIn multivariate analyses, the following variables were used: gender, age, prednisolone only, methotrexate only, sulfasalazine only, hydroxychloroquine only, tumour necrosis factor-blocking agents, combination of disease-modifying antirheumatic drugs, pack-years, smoking, erosions, DAS28 (disease activity score using 28 joint counts), body mass index, pulse rate, creatinine levels, renal clearance, hypothyroidism and diabetes mellitus. CI, confidence interval; OR, odds ratio.Therefore, to get more support for a drug-specific effect, it is of interest to know whether or not in the study of Toms and colleagues the MTX effect was present only in the group of RA patients with single use of MTX or in the group of MTX-treated patients with other antirheumatic drugs. As patients with MetS were significantly older, it would give further information whether age was an independent risk factor for MetS in regression analyses. Moreover, as readers, we are not informed about comorbidities like diabetes and clinical hypothyroidism, which are notorious cardiometabolic risk factors. On the whole, we could not confirm a plausible protective role for the use of MTX and presence of MetS, and hence further investigation is required to explain the discrepancy between our findings and those of Toms and colleagues. 相似文献
Table 1
Characteristics of the study populationMetS presenta | MetS absenta | MetS presentb | MetS absentb | |||
---|---|---|---|---|---|---|
n = 84 | n = 265 | n = 121 | n = 228 | P valuea | P valueb | |
Demographics | ||||||
Age, years | 63.8 (± 8) | 63.1 (± 7) | 64.3 (± 8) | 62.7 (± 7) | 0.46 | 0.045 |
Female, percentage | 76 | 63 | 74 | 62 | 0.022 | 0.028 |
RA-related characteristics | ||||||
DAS28 | 4.2 (± 1.3) | 3.9 (± 1.4) | 4.1 (± 1.3) | 3.8 (± 1.4) | 0.21 | 0.062 |
ESR, mm/hour | 22 (10-35) | 16 (9-30) | 20 (10-34) | 17 (9-31) | 0.059 | 0.33 |
CRP, mg/L | 11 (4-21) | 6 (3-16) | 8 (3-18) | 6 (3-19) | 0.021 | 0.46 |
RA duration, years | 7 (4-10) | 7 (4-10) | 7 (4-10) | 7 (5-10) | 0.83 | 0.19 |
Erosion, percentage | 77 | 83 | 79 | 83 | 0.20 | 0.36 |
Number of DMARDs | 1 (1-2) | 1 (1-1) | 1 (1-2) | 1 (1-1) | 0.26 | 0.43 |
MTX current, percentage | 62 | 60 | 63 | 59 | 0.71 | 0.46 |
MTX only, percentage | 39 | 39 | 41 | 38 | 0.95 | 0.67 |
SSZ only, percentage | 8 | 13 | 9 | 14 | 0.23 | 0.22 |
HCQ only, percentage | 1 | 4 | 3 | 4 | 0.31 | 0.55 |
Combination of DMARDs, percentage | 31 | 25 | 29 | 25 | 0.24 | 0.38 |
TNF-blocking agent, percentage | 11 | 9 | 11 | 9 | 0.73 | 0.65 |
Prednisolone only, percentage | 1 | 2 | 3 | 1 | 1.00 | 0.42 |
Cardiovascular risk factors | ||||||
Current smoker, percentage | 26 | 31 | 25 | 32 | 0.42 | 0.15 |
Pack-years, years | 17 (0-34) | 19 (2-38) | 19 (0-35) | 18 (2-38) | 0.23 | 0.75 |
BMI, kg/m2 | 30 (± 4) | 26 (± 5) | 29 (± 4) | 25 (± 5) | < 0.001 | < 0.001 |
Creatinine, μmol/L | 89 (± 21) | 89 (± 16) | 91 (± 22) | 87 (± 14) | 0.99 | 0.070 |
Renal clearance, mL/minute | 81 (± 24) | 72 (± 19) | 77 (± 23) | 73 (± 19) | 0.003 | 0.062 |
Pulse, beats per minute | 76 (± 11) | 73 (± 9) | 75 (± 11) | 73 (± 9) | 0.005 | 0.015 |
Diabetes mellitus, percentage | 14 | 3 | 12 | 3 | < 0.001 | 0.001 |
Hypothyroidism, percentage | 12 | 2 | 9 | 2 | 0.001 | 0.003 |
Table 2
Variables associated with metabolic syndromeUnivariate | Multivariatea | |||||
---|---|---|---|---|---|---|
OR | 95% CI | P value | OR | 95% CI | P value | |
Body mass index | 1.2 | 1.1-1.3 | < 0.001 | 1.2 | 1.1-1.3 | < 0.001 |
Pulse | 1.03 | 1.01-1.06 | 0.011 | 1.03 | 1.00-1.06 | 0.020 |
Creatinine | 1.01 | 1.00-1.02 | 0.080 | 1.02 | 1.00-1.03 | 0.017 |
Hypothyroidism | 4.5 | 1.5-13.2 | 0.007 | 4.7 | 1.5-15.0 | 0.009 |
Diabetes mellitus | 4.8 | 1.8-12.9 | 0.002 | 4.5 | 1.4-15.2 | 0.014 |