641 research outputs found

    Performance of current microbial tests for screening antibiotics in sheep and goat milk

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    [EN] The detection capability (CC beta) of some microbial screening tests currently available was calculated for sheep and goat milk in accordance with Commission Decision 657/2002/EC. The CC beta was at or below the maximum residue limit (MRL) for most beta-lactams assessed and other non-beta-lactam drugs such as neomycin, tylosin, sulfadiazine and sulfadimethoxine. However, the tests were less sensitive in the detection of most non-beta-lactam drugs such as quinolones and tetracyclines at safety levels. When individual sheep milk samples free of antibiotics were analysed, an elevated somatic cell count was related to the occurrence of non-compliant results in all the methods assessed. To guarantee the safety of milk and dairy products from small ruminants, the periodical implementation of screening tests more sensitive towards non-beta-lactam drugs would be appropriate. (C) 2014 Elsevier Ltd. All rights reserved.This research forms part of the Project AGL2009-11524 financed by the Ministerio de Ciencia e Innovacion (Madrid, Spain).Beltrán Martínez, MC.; Berruga Fernandez, MI.; Molina Casanova, A.; Lisandro Althaus, R.; Molina Pons, MP. (2015). Performance of current microbial tests for screening antibiotics in sheep and goat milk. International Dairy Journal. 41:13-15. https://doi.org/10.1016/j.idairyj.2014.09.007S13154

    Modelling sea breeze climatologies and interactions on coasts in the southern North Sea: Implications for offshore wind energy

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    Current understanding of the behaviour of sea breezes in the offshore environment is limited but rapidly requires improvement due, not least, to the expansion of the offshore wind energy industry. Here we report on contrasting characteristics of three sea-breeze types on five coastlines around the southern North Sea from an 11 year model-simulated climatology. We present and test an identification method which distinguishes sea-breeze types which can, in principle, be adapted for other coastlines around the world. The coherence of the composite results for each type demonstrates that the method is very effective in resolving and distinguishing characteristics and features. Some features, such as jets and calm zones, are shown to influence offshore wind farm development areas, including the sites of the proposed wind farms up to 200 km offshore. A large variability in sea-breeze frequency between neighbouring coastlines of up to a factor of 3 is revealed. Additionally, there is a strong association between sea-breeze type on one coastline and that which may form coincidentally on another nearby. This association can be as high as 86% between, for example, the North Norfolk and East Norfolk coasts. We show, through associations between sea-breeze events on coastlines with contrasting orientations, that each coastline can be important for influencing the wind climate of another. Furthermore, we highlight that each sea-breeze type needs separate consideration in wind power resource assessment and that future larger turbines will be more sensitive to sea-breeze impacts

    Pulmonary fibrosis induced by H5N1 viral infection in mice

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    <p>Abstract</p> <p>Background</p> <p>Inflammatory process results in lung injury that may lead to pulmonary fibrosis (PF). Here, we described PF in mice infected with H5N1 virus.</p> <p>Methods</p> <p>Eight-week-old BALB/c mice were inoculated intranasally with 1 × 10<sup>1 </sup>MID<sub>50 </sub>of A/Chicken/Hebei/108/2002(H5N1) viruses. Lung injury/fibrosis was evaluated by observation of hydroxyproline concentrations, lung indexes, and histopathology on days 7, 14, and 30 postinoculation.</p> <p>Results</p> <p>H5N1-inoculated mice presented two stages of pulmonary disease over a 30-d period after infection. At acute stage, infected-mice showed typical diffuse pneumonia with inflammatory cellular infiltration, alveolar and interstitial edema and hemorrhage on day 7 postinoculation. At restoration stage, most infected-mice developed PF of different severities on day 30 postinoculation, and 18% of the survived mice underwent severe interstitial and intra-alveolar fibrosis with thickened alveolar walls, collapsed alveoli and large fibrotic areas. The dramatically elevated hydroxyproline levels in H5N1-infected mice showed deposition of collagen in lungs, and confirmed fibrosis of lungs. The dry lung-to-body weight ratio was significantly increased in infected group, which might be associated with the formation of PF in H5N1-infected mice.</p> <p>Conclusion</p> <p>Our findings show that H5N1-infected mice develop the typical PF during restoration period, which will contribute to the investigation of fibrogenesis and potential therapeutic intervention in human H5N1 disease.</p

    Role of microbial biofilms in the maintenance of oral health and in the development of dental caries and periodontal diseases. Consensus report of group 1 of the Joint EFP/ORCA workshop on the boundaries between caries and periodontal disease.

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    BACKGROUND AND AIMS: The scope of this working group was to review (1) ecological interactions at the dental biofilm in health and disease, (2) the role of microbial communities in the pathogenesis of periodontitis and caries, and (3) the innate host response in caries and periodontal diseases. RESULTS AND CONCLUSIONS: A health-associated biofilm includes genera such as Neisseria, Streptococcus, Actinomyces, Veillonella and Granulicatella. Microorganisms associated with both caries and periodontal diseases are metabolically highly specialized and organized as multispecies microbial biofilms. Progression of these diseases involves multiple microbial interactions driven by different stressors. In caries, the exposure of dental biofilms to dietary sugars and their fermentation to organic acids results in increasing proportions of acidogenic and aciduric species. In gingivitis, plaque accumulation at the gingival margin leads to inflammation and increasing proportions of proteolytic and often obligately anaerobic species. The natural mucosal barriers and saliva are the main innate defence mechanisms against soft tissue bacterial invasion. Similarly, enamel and dentin are important hard tissue barriers to the caries process. Given that the present state of knowledge suggests that the aetiologies of caries and periodontal diseases are mutually independent, the elements of innate immunity that appear to contribute to resistance to both are somewhat coincidental

    A Reduction in Ribonucleotide Reductase Activity Slows Down the Chromosome Replication Fork but Does Not Change Its Localization

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    BACKGROUND:It has been proposed that the enzymes of nucleotide biosynthesis may be compartmentalized or concentrated in a structure affecting the organization of newly replicated DNA. Here we have investigated the effect of changes in ribonucleotide reductase (RNR) activity on chromosome replication and organization of replication forks in Escherichia coli. METHODOLOGY/PRINCIPAL FINDINGS:Reduced concentrations of deoxyribonucleotides (dNTPs) obtained by reducing the activity of wild type RNR by treatment with hydroxyurea or by mutation, resulted in a lengthening of the replication period. The replication fork speed was found to be gradually reduced proportionately to moderate reductions in nucleotide availability. Cells with highly extended C periods showed a "delay" in cell division i.e. had a higher cell mass. Visualization of SeqA structures by immunofluorescence indicated no change in organization of the new DNA upon moderate limitation of RNR activity. Severe nucleotide limitation led to replication fork stalling and reversal. Well defined SeqA structures were not found in situations of extensive replication fork repair. In cells with stalled forks obtained by UV irradiation, considerable DNA compaction was observed, possibly indicating a reorganization of the DNA into a "repair structure" during the initial phase of the SOS response. CONCLUSION/SIGNIFICANCE:The results indicate that the replication fork is slowed down in a controlled manner during moderate nucleotide depletion and that a change in the activity of RNR does not lead to a change in the organization of newly replicated DNA. Control of cell division but not control of initiation was affected by the changes in replication elongation

    Entering and Exiting the Medicare Part D Coverage Gap: Role of Comorbidities and Demographics

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    Background: Some Medicare Part D enrollees whose drug expenditures exceed a threshold enter a coverage gap with full cost-sharing, increasing their risk for reduced adherence and adverse outcomes. Objective: To examine comorbidities and demographic characteristics associated with gap entry and exit. Design: We linked 2005-2006 pharmacy, outpatient, and inpatient claims to enrollment and Census data. We used logistic regression to estimate associations of 2006 gap entry and exit with 2005 medical comorbidities, demographics, and Census block characteristics. We expressed all results as predicted percentages. PATIENTS: 287,713 patients without gap coverage, continuously enrolled in a Medicare Advantage Part D (MAPD) plan serving eight states. Patients who received a low-income subsidy, could not be geocoded, or had no 2006 drug fills were excluded. Results: Of enrollees, 15.9% entered the gap, 2.6% within the first 180 days; among gap enterers, only 6.7% exited again. Gap entry was significantly associated with female gender and all comorbidities, particularly dementia (39.5% gap entry rate) and diabetes (28.0%). Among dementia patients entering the gap, anti-dementia drugs (donepezil, memantine, rivastigmine, and galantamine) and atypical antipsychoticmedications (risperidone, quetiapine, and olanzapine) together accounted for 40% of pre-gap expenditures. Among diabetic patients, rosiglitazone accounted for 7.2% of pre-gap expenditures. Having dementia was associated with twice the risk of gap exit. Conclusions: Certain chronically ill MAPD enrollees are at high risk of gap entry and exposure to unsubsidized medication costs. Clinically vulnerable populations should be counseled on how to best manage costs through drug substitution or discontinuation of specific, non-essential medications. © 2010 Society of General Internal Medicine

    Combined effects of cigarette smoking, gene polymorphisms and methylations of tumor suppressor genes on non small cell lung cancer: a hospital-based case-control study in China

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    <p>Abstract</p> <p>Background</p> <p>Cigarette smoking is the most established risk factor, and genetic variants and/or gene promoter methylations are also considered to play an essential role in development of lung cancer, but the pathogenesis of lung cancer is still unclear.</p> <p>Methods</p> <p>We collected the data of 150 cases and 150 age-matched and sex-matched controls on a Hospital-Based Case-Control Study in China. Face to face interviews were conducted using a standardized questionnaire. Gene polymorphism and methylation status were measured by RFLP-PCR and MSP, respectively. Logistic regressive model was used to estimate the odds ratios (OR) for different levels of exposure.</p> <p>Results</p> <p>After adjusted age and other potential confounding factors, smoking was still main risk factor and significantly increased 3.70-fold greater risk of NSCLC as compared with nonsmokers, and the ORs across increasing levels of pack years were 1, 3.54, 3.65 and 7.76, which the general dose-response trend was confirmed. Our striking findings were that the risk increased 5.16, 8.28 and 4.10-fold, respectively, for NSCLC with promoter hypermethylation of the <it>p16</it>, <it>DAPK </it>or <it>RARβ </it>gene in smokers with <it>CYP1A1 </it>variants, and the higher risk significantly increased in smokers with null <it>GSTM1 </it>and the OR was 17.84 for NSCLC with <it>p16 </it>promoter hypermethylation, 17.41 for <it>DAPK</it>, and 8.18 for <it>RARβ </it>in smokers with null <it>GSTM1 </it>compared with controls (all p < 0.01).</p> <p>Conclusion</p> <p>Our study suggests the strong combined effects of cigarette smoke, <it>CYP1A1 </it>and <it>GSTM1 </it>Polymorphisms, hypermethylations of <it>p16</it>, <it>DAPK </it>and <it>RARβ </it>promoters in NSCLC, implying complex pathogenesis of NSCLC should be given top priority in future research.</p

    Effective Rheology of Bubbles Moving in a Capillary Tube

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    We calculate the average volumetric flux versus pressure drop of bubbles moving in a single capillary tube with varying diameter, finding a square-root relation from mapping the flow equations onto that of a driven overdamped pendulum. The calculation is based on a derivation of the equation of motion of a bubble train from considering the capillary forces and the entropy production associated with the viscous flow. We also calculate the configurational probability of the positions of the bubbles.Comment: 4 pages, 1 figur
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