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91.
Lisa R. W. Plano Tomoyuki Shibata Anna C. Garza Jonathan Kish Jay M. Fleisher Christopher D. Sinigalliano Maribeth L. Gidley Kelly Withum Samir M. Elmir Suzanne Hower Charlene R. Jackson John B. Barrett Timothy Cleary Maureen Davidson Johnnie Davis Sampa Mukherjee Lora E. Fleming Helena M. Solo-Gabriele 《Microbial ecology》2013,65(4):1039-1051
Reports of Staphylococcus aureus including methicillin-resistant S. aureus (MRSA) detected in marine environments have occurred since the early 1990s. This investigation sought to isolate and characterize S. aureus from marine waters and sand at a subtropical recreational beach, with and without bathers present, in order to investigate possible sources and to identify the risks to bathers of exposure to these organisms. During 40 days over 17 months, 1,001 water and 36 intertidal sand samples were collected by either bathers or investigators at a subtropical recreational beach. Methicillin-sensitive S. aureus (MSSA) and MRSA were isolated and identified using selective growth media and an organism-specific molecular marker. Antimicrobial susceptibility, staphylococcal cassette chromosome mec (SCCmec) type, pulsed-field gel electrophoresis (PFGE) pattern, multi-locus sequence type (MLST), and staphylococcal protein A (spa) type were characterized for all MRSA. S. aureus was isolated from 248 (37 %) bather nearby water samples at a concentration range of <2–780 colony forming units per ml, 102 (31 %) ambient water samples at a concentration range of <2–260 colony forming units per ml, and 9 (25 %) sand samples. Within the sand environment, S. aureus was isolated more often from above the intertidal zone than from intermittently wet or inundated sand. A total of 1334 MSSA were isolated from 37 sampling days and 22 MRSA were isolated from ten sampling days. Seventeen of the 22 MRSA were identified by PFGE as the community-associated MRSA USA300. MRSA isolates were all SCCmec type IVa, encompassed five spa types (t008, t064, t622, t688, and t723), two MLST types (ST8 and ST5), and 21 of 22 isolates carried the genes for Panton–Valentine leukocidin. There was a correlation (r?=?0.45; p?=?0.05) between the daily average number of bathers and S. aureus in the water; however, no association between exposure to S. aureus in these waters and reported illness was found. This report supports the concept that humans are a potential direct source for S. aureus in marine waters. 相似文献
92.
M. H. Depledge A. J. Harvey C. Brownlee M. Frost M. N. Moore L. E. Fleming 《Microbial ecology》2013,65(4):852-859
Early steps in the emergence of the discipline of “Oceans and Human Health” are charted in the USA and discussed in relation to past and present marine environment and human health research activities in Europe. Differences in terminology are considered, as well as differences in circumstances related to the various seas of Europe and the intensity of human coastal activity and impact. Opportunities to progress interdisciplinary research are described, and the value of horizon scanning for the early identification of emerging issues is highlighted. The challenges facing researchers and policymakers addressing oceans and human health issues are outlined and some suggestions offered regarding how further progress in research and training into both the risks and benefits of Oceans and Human Health might be made on both sides of the Atlantic. 相似文献
93.
Hui Xiong Melinda Foulk Lisa Aschenbrenner Jun Fan Choi-Lai Tiong-Yip Kenneth D. Johnson Demetri Moustakas Paul R. Fleming Dean G. Brown Minli Zhang Douglas Ferguson Dedong Wu Qin Yu 《Bioorganic & medicinal chemistry letters》2013,23(24):6789-6793
Targeting viral polymerases has been a proven and attractive strategy for antiviral drug discovery. Herein we describe our effort in improving the antiviral activity and physical properties of a series of benzothienoazepine compounds as respiratory syncytial virus (RSV) RNA polymerase inhibitors. The antiviral activity and spectrum of this class was significantly improved by exploring the amino substitution of the pyridine ring, resulting in the discovery of the most potent RSV A polymerase inhibitors reported to date. 相似文献
94.
95.
Jeremy Howick Claire Friedemann Maria Tsakok Robert Watson Teresa Tsakok Jennifer Thomas Rafael Perera Susannah Fleming Carl Heneghan 《PloS one》2013,8(5)
BackgroundPlacebos are widely used in clinical practice in spite of ethical restrictions. Whether such use is justified depends in part on the relative benefit of placebos compared to ‘active’ treatments. A direct test for differences between placebo and ‘active’ treatment effects has not been conducted.ObjectivesWe aimed to test for differences between treatment and placebo effects within similar trial populations.ResultsIn trials with continuous outcomes (n = 115) we found no difference between treatment and placebo effects (MD = −0.29, 95% CI −0.62 to 0.05, P = 0.10). In trials with binary outcomes (n = 37) treatments were significantly more effective than placebos (RRR = 0.72, 95%CI = 0.61 to 0.86, P = 0.0003). Treatment and placebo effects were not different in 22 out of 28 predefined subgroup analyses. Of the six subgroups with differences treatments were more effective than placebos in five. However when all criteria for reducing bias were ruled out (continuous outcomes) placebos were more effective than treatments (MD = 1.59, 95% CI = 0.40 to 2.77, P = 0.009).
Conclusions and Implications
Placebos and treatments often have similar effect sizes. Placebos with comparatively powerful effects can benefit patients either alone or as part of a therapeutic regime, and trials involving such placebos must be adequately blinded. 相似文献96.
James C. Geoghegan Ryan Fleming Melissa Damschroder Steven M. Bishop Hasige A. Sathish 《MABS-AUSTIN》2016,8(5):941-950
Undesired solution behaviors such as reversible self-association (RSA), high viscosity, and liquid-liquid phase separation can introduce substantial challenges during development of monoclonal antibody formulations. Although a global mechanistic understanding of RSA (i.e., native and reversible protein-protein interactions) is sufficient to develop robust formulation controls, its mitigation via protein engineering requires knowledge of the sites of protein-protein interactions. In the study reported here, we coupled our previous hydrogen-deuterium exchange mass spectrometry findings with structural modeling and in vitro screening to identify the residues responsible for RSA of a model IgG1 monoclonal antibody (mAb-C), and rationally engineered variants with improved solution properties (i.e., reduced RSA and viscosity). Our data show that mutation of either solvent-exposed aromatic residues within the heavy and light chain variable regions or buried residues within the heavy chain/light chain interface can significantly mitigate RSA and viscosity by reducing the IgG's surface hydrophobicity. The engineering strategy described here highlights the utility of integrating complementary experimental and in silico methods to identify mutations that can improve developability, in particular, high concentration solution properties, of candidate therapeutic antibodies. 相似文献
97.
Shelley W. Peterson Natalie C. Knox George R. Golding Shaun D. Tyler Andrea D. Tyler Philip Mabon Joanne E. Embree Fiona Fleming Sergio Fanella Gary Van Domselaar Michael R. Mulvey Morag R. Graham 《PloS one》2016,11(3)
Whereas the infant gut microbiome is the subject of intense study, relatively little is known regarding the nares microbiome in newborns and during early life. This study aimed to survey the typical composition and diversity of human anterior nare microflora for developing infants over time, and to explore how these correlate to their primary caregivers. Single nare swabs were collected at five time points over a one-year period for each subject from infant-caregiver pairs. Our study comprised of 50 infants (recruited at 2 weeks, post delivery) and their 50 primary caregivers. Applying the chaperonin-60 (cpn60) universal target (UT) amplicon as our molecular barcoding marker to census survey the microbial communities, we longitudinally surveyed infant nares microbiota at 5 time points over the course of the first year of life. The inter- and intra-subject diversity was catalogued and compared, both longitudinally and relative to their adult primary caregivers. Although within-subject variability over time and inter-subject variability were both observed, the assessment detected only one or two predominant genera for individual infant samples, belonging mainly to phyla Actinobacteria, Firmicutes, and Proteobacteria. Consistent with previously observed microbial population dynamics in other body sites, the diversity of nares microflora increased over the first year of life and infants showed differential operational taxonomic units (OTUs) relative to their matched primary caregiver. The collected evidence also support that both temporal and seasonal changes occur with respect to carriage of potentially pathogenic bacteria (PPBs), which may influence host predisposition to infection. This pilot study surveying paired infant/caregiver nare microbiomes provides novel longitudinal diversity information that is pertinent to better understanding nare microbiome development in infants. 相似文献
98.
Sarah O’Connell Darren Lillis Aoife Cotter Siobhan O’Dea Helen Tuite Catherine Fleming Brendan Crowley Ian Fitzgerald Linda Dalby Helen Barry Darragh Shields Suzanne Norris Patrick K. Plunkett Colm Bergin 《PloS one》2016,11(3)
Objectives
Studies suggest 2 per 1000 people in Dublin are living with HIV, the level above which universal screening is advised. We aimed to assess the feasibility and acceptability of a universal opt-out HIV, Hepatitis B and Hepatitis C testing programme for Emergency Department patients and to describe the incidence and prevalence of blood-borne viruses in this population.Methods
An opt-out ED blood borne virus screening programme was piloted from March 2014 to January 2015. Patients undergoing blood sampling during routine clinical care were offered HIV 1&2 antibody/antigen assay, HBV surface antigen and HCV antibody tests. Linkage to care where necessary was co-ordinated by the study team. New diagnosis and prevalence rates were defined as the new cases per 1000 tested and number of positive tests per 1000 tested respectively.Results
Over 45 weeks of testing, of 10,000 patient visits, 8,839 individual patient samples were available for analysis following removal of duplicates. A sustained target uptake of >50% was obtained after week 3. 97(1.09%), 44(0.49%) and 447(5.05%) HIV, Hepatitis B and Hepatitis C tests were positive respectively. Of these, 7(0.08%), 20(0.22%) and 58(0.66%) were new diagnoses of HIV, Hepatitis B and Hepatitis C respectively. The new diagnosis rate for HIV, Hepatitis B and Hepatitis C was 0.8, 2.26 and 6.5 per 1000 and study prevalence for HIV, Hepatitis B and Hepatitis C was 11.0, 5.0 and 50.5 per 1000 respectively.Conclusions
Opt-out blood borne viral screening was feasible and acceptable in an inner-city ED. Blood borne viral infections were prevalent in this population and newly diagnosed cases were diagnosed and linked to care. These results suggest widespread blood borne viral testing in differing clinical locations with differing population demographic risks may be warranted. 相似文献99.
Jane Fleming Morag Farquhar Cambridge City over-s Cohort study collaboration Carol Brayne Stephen Barclay 《PloS one》2016,11(4)
IntroductionIncreasing longevity means more people will be dying in very old age, but little is known about the preferences of the ‘oldest old’ regarding their care at the end of life.AimsTo understand very old people’s preferences regarding care towards the end of life and attitudes towards dying, to inform policy and practice.MethodsQualitative data collection for n = 42 population-based cohort study participants aged 95–101 (88% women, 42% in long-term-care): topic-guided interviews with n = 33 participants and n = 39 proxy informants, most with both (n = 30: 4 jointly + separate interviews for 26 dyads).ResultsDeath was a part of life: these very old people mainly live day-to-day. Most were ready to die, reflecting their concerns regarding quality of life, being a nuisance, having nothing to live for and having lived long enough. Contrasting views were rare exceptions but voiced firmly. Most were not worried about death itself, but concerned more about the dying process and impacts on those left behind; a peaceful and pain-free death was a common ideal. Attitudes ranged from not wanting to think about death, through accepting its inevitable approach to longing for its release. Preferring to be made comfortable rather than have life-saving treatment if seriously ill, and wishing to avoid hospital, were commonly expressed views. There was little or no future planning, some consciously choosing not to. Uncertainty hampered end-of-life planning even when death was expected soon. Some stressed circumstances, such as severe dependency and others’ likely decision-making roles, would influence choices. Carers found these issues harder to raise but felt they would know their older relatives’ preferences, usually palliative care, although we found two discrepant views.ConclusionsThis study’s rare data show ≥95-year-olds are willing to discuss dying and end-of-life care but seldom do. Formal documentation of wishes is extremely rare and may not be welcome. Although being “ready to die” and preferring a palliative approach predominated, these preferences cannot be assumed. 相似文献
100.
Effects of canola and high‐oleic‐acid canola oils on abdominal fat mass in individuals with central obesity 下载免费PDF全文