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21.
Japanese knotweed s.l. comprises Fallopia japonica, F. sachalinensis, F. × bohemica and any F2s or backcrosses. The parental taxa were introduced from the East to the West as garden ornamentals in the nineteenth
century, and soon spread beyond the confines of the garden to become widespread and persistent weeds. Since only female F. japonica var. japonica was introduced, its impressive spread has occurred solely by vegetative means. However, the initial lack of genetic variability
has been complemented by an extensive series of hybridisations in the adventive range. We examine the history, spread, reproductive
biology and ecological impact of these species in the West. The role and importance of polyploidy and hybridisation in their
invasion of the West is discussed, as are the implications of these factors for the potential further evolution of the group. 相似文献
22.
Daniels JP Hunc K Cochrane DD Carr R Shaw NT Taylor A Heathcote S Brant R Lim J Ansermino JM 《CMAJ》2012,184(1):29-34
Background:
Identifying adverse events and near misses is essential to improving safety in the health care system. Patients are capable of reliably identifying and reporting adverse events. The effect of a patient safety reporting system used by families of pediatric inpatients on reporting of adverse events by health care providers has not previously been investigated.Methods:
Between Nov. 1, 2008, and Nov. 30, 2009, families of children discharged from a single ward of British Columbia’s Children’s Hospital were asked to respond to a questionnaire about adverse events and near misses during the hospital stay. Rates of reporting by health care providers for this period were compared with rates for the previous year. Family reports for specific incidents were matched with reports by health care providers to determine overlap.Results:
A total of 544 familes responded to the questionnaire. The estimated absolute increase in reports by health care providers per 100 admissions was 0.5% (95% confidence interval −1.8% to 2.7%). A total of 321 events were identified in 201 of the 544 family reports. Of these, 153 (48%) were determined to represent legitimate patient safety concerns. Only 8 (2.5%) of the adverse events reported by families were also reported by health care providers.Interpretation:
The introduction of a family-based system for reporting adverse events involving pediatric inpatients, administered at the time of discharge, did not change rates of reporting of adverse events and near misses by health care providers. Most reports submitted by families were not duplicated in the reporting system for health care providers, which suggests that families and staff members view safety-related events differently. However, almost half of the family reports represented legitimate patient safety concerns. Families appeared capable of providing valuable information for improving the safety of pediatric inpatients.It has been estimated that adverse events occur in about 1% of children treated in hospital and that, on average, 60% of these events are preventable.1 To increase institutional awareness of adverse events, hospitals have implemented systems to encourage health care providers to report adverse events.2 The reporting of adverse events can be improved by making electronic systems for reporting readily accessible3 and by ensuring a “just culture,” which includes nonpunitive reporting policies.4 However, adverse events reported by health care providers account for only a small fraction of total adverse events as determined by chart review.5 Time pressures to treat patients, fear of punishment, lack of belief in the benefit of reporting and differing opinions of what defines a reportable event contribute to low reporting rates.6 However, patients and their families are readily available, keen and motivated observers who may not be subject to these reporting barriers. Family members are capable of observing and reporting adverse events in a variety of clinical settings.7 It is known that the interpretation of safety events and the threshold for reporting differ among health care disciplines and individual health care providers.6 However, it is not clear how families of pediatric patients interpret safety-related events or what their threshold would be for reporting events.The purpose of this study was to test whether the introduction of an adverse event reporting system for use by families of pediatric patients at the time of discharge from a surgical ward would significantly change the rate of reporting of adverse events by health care providers. We also evaluated the types of events that families reported, the relevance of these events with respect to patient safety, families’ desires for anonymous reporting and families’ assessments of institutional responses to reported events. We anticipated that health care providers’ reporting rates would rise with the introduction of the family reporting system, on the assumption that greater attention would be paid to reporting safety-related events on the ward. We also anticipated that families would provide useful information about safety-related events, at least some of the time. In particular, we thought that facilitating communication from the patient’s family directly to the study institution’s Quality, Safety and Outcome Improvement Department would allow more opportunities to improve safety through changes in practice. 相似文献23.
Repeated inoculation as a strategy for the remediation of low concentrations of phenanthrene in soil
Phenanthrene, a polycyclic aromatic hydrocarbon, becomes increasingly unavailable to microorganisms for degradation as it ages in soil. Consequently, many bioaugmentation efforts to remediate polycyclic aromatic hydrocarbons in soil have failed. We studied theeffect of repeatedly inoculating a soil with a phenanthrene-degrading Arthrobacter sp. on the mineralization kinetics of low concentrations of phenanthrene. After the first inoculation, the initial mineralization rate of 50 ng/g phenanthrene declined in a biphasicexponential pattern. By three hundred hours after inoculation, there was no difference in mineralization rates between the inoculated and uninoculated treatments even though a large fraction of the phenanthrene had not yet been mineralized. A second and third inoculation significantly increased the mineralization rate, suggesting that, though themineralization rate declined, phenanthrene remained bioavailable. Restirring the soil, without inoculation, did not produce similar increases in mineralization rates, suggesting absence of contact between cells and phenanthrene on a larger spatial scale (>mm) is not the cause of the mineralization decline. Bacteria inoculated into soil 280 hours beforethe phenanthrene was added could not maintain phenanthrene degradation activity. We suggest sorption lowered bioavailability of phenanthrene below an induction threshold concentration for metabolic activity of phenanthrene-degrading bacteria. 相似文献
24.
Michelle J. Boyle Prasanna Jagannathan Lila A. Farrington Ijeoma Eccles-James Samuel Wamala Tara I McIntyre Hilary M. Vance Katherine Bowen Felistas Nankya Ann Auma Mayimuna Nalubega Esther Sikyomu Kate Naluwu John Rek Agaba Katureebe Victor Bigira James Kapisi Jordan Tappero Mary K Muhindo Bryan Greenhouse Emmanuel Arinaitwe Grant Dorsey Moses R. Kamya Margaret E. Feeney 《PLoS pathogens》2015,11(7)
FoxP3+ regulatory CD4 T cells (Tregs) help to maintain the delicate balance between pathogen-specific immunity and immune-mediated pathology. Prior studies suggest that Tregs are induced by P. falciparum both in vivo and in vitro; however, the factors influencing Treg homeostasis during acute and chronic infections, and their role in malaria immunopathogenesis, remain unclear. We assessed the frequency and phenotype of Tregs in well-characterized cohorts of children residing in a region of high malaria endemicity in Uganda. We found that both the frequency and absolute numbers of FoxP3+ Tregs in peripheral blood declined markedly with increasing prior malaria incidence. Longitudinal measurements confirmed that this decline occurred only among highly malaria-exposed children. The decline of Tregs from peripheral blood was accompanied by reduced in vitro induction of Tregs by parasite antigen and decreased expression of TNFR2 on Tregs among children who had intense prior exposure to malaria. While Treg frequencies were not associated with protection from malaria, there was a trend toward reduced risk of symptomatic malaria once infected with P. falciparum among children with lower Treg frequencies. These data demonstrate that chronic malaria exposure results in altered Treg homeostasis, which may impact the development of antimalarial immunity in naturally exposed populations. 相似文献
25.
Background
Anxiety is common, with significant morbidity, but little is known about presentations and recording of anxiety diagnoses and symptoms in primary care. This study aimed to determine trends in incidence and socio-demographic variation in General Practitioner (GP) recorded diagnoses of anxiety, mixed anxiety/depression, panic and anxiety symptoms.Methodology/Principal Findings
Annual incidence rates of anxiety diagnoses and symptoms were calculated from 361 UK general practices contributing to The Health Improvement Network (THIN) database between 1998 and 2008, adjusted for year of diagnosis, gender, age, and deprivation. Incidence of GP recorded anxiety diagnosis fell from 7.9 to 4.9/1000PYAR from 1998 to 2008, while incidence of anxiety symptoms rose from 3.9 to 5.8/1000PYAR. Incidence of mixed anxiety/depression fell from 4.0 to 2.2/1000PYAR, and incidence of panic disorder fell from 0.9/1000PYAR in 1998 to 0.5/1000PYAR in 2008. All these entries were approximately twice as common in women and more common in deprived areas. GP-recorded anxiety diagnoses, symptoms and mixed anxiety/depression were commonest aged 45–64 years, whilst panic disorder/attacks were more common in those 16–44 years. GPs predominately use broad non-specific codes to record anxiety problems in the UK.Conclusions/Significance
GP recording of anxiety diagnoses has fallen whilst recording of anxiety symptoms has increased over time. The incidence of GP recorded diagnoses of anxiety diagnoses was lower than in screened populations in primary care. The reasons for this apparent under-recording and whether it represents under-detection in those being seen, a reluctance to report anxiety to their GP, or a reluctance amongst GPs to label people with anxiety requires investigation. 相似文献26.
Gene E. Likens Donald C. Buso Brian K. Dresser Emily S. Bernhardt Robert O. Hall Jr Kate H. Macneale Scott W. Bailey 《Restoration Ecology》2004,12(3):419-428
Ground and pelletized Wollastonite (Wo; CaSiO3) was added to a 50‐m reach of an anthropogenically acidified stream within the Hubbard Brook Experimental Forest, New Hampshire, to evaluate its buffering and restoration potential. The Wo was highly effective in raising the pH, acid‐neutralizing capacity (ANC), dissolved inorganic carbon (DIC), and Ca2+ concentrations of the stream water, but during the short duration of the experiment had no discernable effect on the stream biota. After initial, spike‐like fluctuations in pH and concentrations of ANC, DIC, and Ca2+, the relatively slow dissolution rates of the Wo dampened extreme concentrations and contributed to relatively long‐lasting (4 months) amelioration of streamwater acidity. Changes in concentrations of Ca2+, dissolved Si, ANC, and DIC were inversely related to streamflow. After several high, stream‐discharge events, concentrations quickly and consistently returned to pre‐event conditions. 相似文献
27.
Cheeseman MT Tyrer HE Williams D Hough TA Pathak P Romero MR Hilton H Bali S Parker A Vizor L Purnell T Vowell K Wells S Bhutta MF Potter PK Brown SD 《PLoS genetics》2011,7(10):e1002336
Otitis media with effusion (OME) is the commonest cause of hearing loss in children, yet the underlying genetic pathways and mechanisms involved are incompletely understood. Ventilation of the middle ear with tympanostomy tubes is the commonest surgical procedure in children and the best treatment for chronic OME, but the mechanism by which they work remains uncertain. As hypoxia is a common feature of inflamed microenvironments, moderation of hypoxia may be a significant contributory mechanism. We have investigated the occurrence of hypoxia and hypoxia-inducible factor (HIF) mediated responses in Junbo and Jeff mouse mutant models, which develop spontaneous chronic otitis media. We found that Jeff and Junbo mice labeled in vivo with pimonidazole showed cellular hypoxia in inflammatory cells in the bulla lumen, and in Junbo the middle ear mucosa was also hypoxic. The bulla fluid inflammatory cell numbers were greater and the upregulation of inflammatory gene networks were more pronounced in Junbo than Jeff. Hif-1α gene expression was elevated in bulla fluid inflammatory cells, and there was upregulation of its target genes including Vegfa in Junbo and Jeff. We therefore investigated the effects in Junbo of small-molecule inhibitors of VEGFR signaling (PTK787, SU-11248, and BAY 43-9006) and destabilizing HIF by inhibiting its chaperone HSP90 with 17-DMAG. We found that both classes of inhibitor significantly reduced hearing loss and the occurrence of bulla fluid and that VEGFR inhibitors moderated angiogenesis and lymphangiogenesis in the inflamed middle ear mucosa. The effectiveness of HSP90 and VEGFR signaling inhibitors in suppressing OM in the Junbo model implicates HIF-mediated VEGF as playing a pivotal role in OM pathogenesis. Our analysis of the Junbo and Jeff mutants highlights the role of hypoxia and HIF-mediated pathways, and we conclude that targeting molecules in HIF-VEGF signaling pathways has therapeutic potential in the treatment of chronic OM. 相似文献
28.
29.
Transcranial magnetic stimulation (TMS) has proven to be a useful tool in investigating the role of the articulatory motor cortex in speech perception. Researchers have used single-pulse and repetitive TMS to stimulate the lip representation in the motor cortex. The excitability of the lip motor representation can be investigated by applying single TMS pulses over this cortical area and recording TMS-induced motor evoked potentials (MEPs) via electrodes attached to the lip muscles (electromyography; EMG). Larger MEPs reflect increased cortical excitability. Studies have shown that excitability increases during listening to speech as well as during viewing speech-related movements. TMS can be used also to disrupt the lip motor representation. A 15-min train of low-frequency sub-threshold repetitive stimulation has been shown to suppress motor excitability for a further 15-20 min. This TMS-induced disruption of the motor lip representation impairs subsequent performance in demanding speech perception tasks and modulates auditory-cortex responses to speech sounds. These findings are consistent with the suggestion that the motor cortex contributes to speech perception. This article describes how to localize the lip representation in the motor cortex and how to define the appropriate stimulation intensity for carrying out both single-pulse and repetitive TMS experiments. 相似文献
30.
Synthesis and activity of small molecule GPR40 agonists 总被引:2,自引:0,他引:2
Garrido DM Corbett DF Dwornik KA Goetz AS Littleton TR McKeown SC Mills WY Smalley TL Briscoe CP Peat AJ 《Bioorganic & medicinal chemistry letters》2006,16(7):1840-1845
The first report on the identification and structure-activity relationships of a novel series of GPR40 agonists based on a 3-(4-{[N-alkyl]amino}phenyl)propanoic acid template is described. Structural modifications to the original screening hit yielded compounds with a 100-fold increase in potency at the human GPR40 receptor and pEC(50)s in the low nanomolar range. The carboxylic acid moiety is not critical for activity but typically elicits an agonistic response higher than those observed with carboxamide replacements. These compounds may prove useful in unraveling the therapeutic potential of this receptor for the treatment of Type 2 diabetes. 相似文献