35 research outputs found

    3-Acyl dihydroflavonols from poplar resins collected by honey bees are active against the bee pathogens Paenibacillus larvae and Ascosphaera apis

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    Honey bees, Apis mellifera, collect antimicrobial plant resins from the environment and deposit them in their nests as propolis. This behavior is of practical concern to beekeepers since the presence of propolis in the hive has a variety of benefits, including the suppression of disease symptoms. To connect the benefits that bees derive from propolis with particular resinous plants, we determined the identity and botanical origin of propolis compounds active against bee pathogens using bioassay-guided fractionation against the bacterium Paenibacillus larvae, the causative agent of American foulbrood. Eleven dihydro-flavonols were isolated from propolis collected in Fallon, NV, including pinobanksin-3-octanoate. This hitherto unknown derivative and five other 3-acyl-dihydroflavonols showed inhibitory activity against both P. larvae (IC50 ¼ 17e68 mM) and Ascosphaera apis (IC50 ¼ 8e23 mM), the fungal agent of chalkbrood. A structure-activity relationship between acyl group size and antimicrobial activity was found, with longer acyl groups increasing activity against P. larvae and shorter acyl groups increasing activity against A. apis. Finally, it was determined that the isolated 3-acyl-dihydroflavonols originated from Populus fremontii, and further analysis showed these compounds can also be found in other North American Populus spp

    Effects of urate, a natural inhibitor of peroxynitrite-mediated toxicity, in the response of Arabidopsis thaliana to the bacterial pathogen Pseudomonas syringae

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    Urate, a natural peroxynitrite scavenger, has been used to investígate the possible role of peroxynitrite during plant-pathogen interactions. Urate greatly reduced lesión formation in Arabidopsis leaves treated with an abiotic peroxynitrite-generating system or with a peroxynitrite solution, indicating that it can act as an effective scavenger in planta. In the interaction with the avirulent Pseudomonas syringae pv. phaseolicola [avrRPNW], cell death in the inoculated área was strongly reduced by urate, without compromising disease resistance. In contrast, urate promoted discrete cell death in response to an isogenic Pseudomonas syringae (awRPMT), which did not trigger an HR when inoculated alone, and it induced resistance and arrest of pathogen growth. Scavenging of peroxynitrite did not modify the response of Arabidopsis to an avirulent strain of Xanthomonas campestris pv campestris, that showed a high resistance to NO and peroxynitrite. Our data indícate that peroxynitrite plays a significant role in the responses of plants to Pseudomonas syrin

    [Avian cytogenetics goes functional] Third report on chicken genes and chromosomes 2015

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    High-density gridded libraries of large-insert clones using bacterial artificial chromosome (BAC) and other vectors are essential tools for genetic and genomic research in chicken and other avian species... Taken together, these studies demonstrate that applications of large-insert clones and BAC libraries derived from birds are, and will continue to be, effective tools to aid high-throughput and state-of-the-art genomic efforts and the important biological insight that arises from them

    Risk Factors for Unplanned Transfer to Intensive Care within 24 Hours of Admission from the Emergency Department in an Integrated Healthcare System

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    BACKGROUND: Emergency department (ED) ward admissions subsequently transferred to the intensive care unit (ICU) within 24 hours have higher mortality than direct ICU admissions

    A theory-based multi-component intervention to increase reactive balance measurement by physiotherapists in three rehabilitation hospitals: an uncontrolled single group study

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    Abstract Background Most implementation interventions in rehabilitation, including physiotherapy, have used passive, non-theoretical approaches without demonstrated effectiveness. The goal of this study was to improve an important domain of physiotherapy practice – reactive balance measurement – with a targeted theory-based multi-component intervention developed using the Theoretical Domains Framework. The primary objective was to determine documented reactive balance measure use in a 12-month baseline, during, and for three months post- intervention. Methods An uncontrolled before-and-after study was completed with physiotherapists at three urban adult rehabilitation hospitals in Ontario, Canada. The 12-month intervention included group meetings, local champions, and health record modifications for a validated reactive balance measure. The primary outcome was the proportion of records with a documented reactive balance measure when balance was assessed pre-, during- and post-intervention. Secondary outcomes were changes in use, knowledge, and confidence post-intervention, differences across sites, and intervention satisfaction. Results Reactive balance was not measured in any of 211 eligible pre-intervention records. Thirty-three physiotherapists enrolled and 28 completed the study. Reactive balance was measured in 31% of 300 eligible records during-intervention, and in 19% of 90 eligible records post-intervention (p < 0.04). Knowledge and confidence significantly increased post-intervention (all p < 0.05). There were significant site differences in use during- and post-intervention (all p < 0.05). Most participants reported satisfaction with intervention content (71%) and delivery (68%). Conclusions Reactive balance measurement was greater among participants during-intervention relative to the baseline, and use was partially sustained post-intervention. Continued study of intervention influences on clinical reasoning and exploration of site differences is warranted
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