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Microbial composition analyses by 16S rRNA sequencing: A proof of concept approach to provenance determination of archaeological ochre
Get PDFThis is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Many archaeological science studies use the concept of “provenance”, where the origins of cultural material can be determined through physical or chemical properties that relate back to the origins of the material. Recent studies using DNA profiling of bacteria have been used for the forensic determination of soils, towards determination of geographic origin. This manuscript presents a novel approach to the provenance of archaeological minerals and related materials through the use of 16S rRNA sequencing analysis of microbial DNA. Through the microbial DNA characterization from ochre and multivariate statistics, we have demonstrated the clear discrimination between four distinct Australian cultural ochre sites
Red cell alloimmunization is associated with development of autoantibodies and increased red cell transfusion requirements in myelodysplastic syndrome
Get PDFUse of published material is allowed under the following terms and conditions: https://creativecommons.org/licenses/by-nc/4.0legalcode. Copies of published material are allowed for personal or internal use. Sharing published material for non-commercial purposes is subject to the following conditions: https://creativecommons.org/licenses/by-nc/4.0/legalcode,sect. 3. Reproducing and sharing published material for commercial purposes is not allowed without permission in writing from the publisher.Up to 90% of patients with a myelodysplastic syndrome require red blood cell transfusion; nevertheless, comprehensive data on red cell alloimmunization in such patients are limited. This study evaluates the incidence and clinical impact of red cell alloimmunization in a large cohort of patients with myelodysplastic syndrome registered in the statewide South Australian-MDS registry. The median age of the 817 patients studied was 73 years, and 66% were male. The cumulative incidence of alloimmunization was 11%. Disease-modifying therapy was associated with a lower risk of alloimmunization while alloimmunization was significantly higher in patients with a revised International Prognostic Scoring System classification of Very Low, Low or Intermediate risk compared to those with a High or Very High risk (P=0.03). Alloantibodies were most commonly directed against antigens in the Rh (54%) and Kell (24%) systems. Multiple alloantibodies were present in 49% of alloimmunized patients. Although 73% of alloimmunized patients developed alloantibodies during the period in which they received their first 20 red cell units, the total number of units transfused was significantly higher in alloimmunized patients than in non-alloimmunized patients (90±100 versus 30±52; P<0.0001). In individual patients, red cell transfusion intensity increased significantly following alloimmunization (2.8±1.3 versus 4.1±2.0; P<0.0001). A significantly higher proportion of alloimmunized patients than non-alloimmunized patients had detectable autoantibodies (65% versus 18%; P<0.0001) and the majority of autoantibodies were detected within a short period of alloimmunization. In conclusion, this study characterizes alloimmunization in a large cohort of patients with myelodysplastic syndrome and demonstrates a signficant increase in red cell transfusion requirements following alloimmunization, most probably due to development of additional alloantibodies and autoantibodies, resulting in subclinical/clinical hemolysis. Strategies to mitigate alloimmunization risk are critical for optimizing red cell transfusion support
Effects of remifentanil on esophageal and esophagogastric junction (EGJ) bolus transit in healthy volunteers using novel pressure‐flow analysis
Get PDFThis article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving'.
© 2017 John Wiley & Sons, Inc. All rights reserved.
This author accepted manuscript is made available following 12 month embargo from date of publication (August 2017) in accordance with the publisher’s archiving policyBackground
Remifentanil is associated with subjective dysphagia and an objective increase in aspiration risk. Studies of opioid effects have shown decreased lower esophageal sphincter relaxation. We assessed bolus transit through the esophagus and esophagogastric junction (EGJ) during remifentanil administration using objective pressure‐flow analysis.
Methods
Data from 11 healthy young participants (23±3 years, 7 M) were assessed for bolus flow through the esophagus and EGJ using high‐resolution impedance manometry (Manoscan™, Sierra Scientific Instruments, Inc., LES Angeles, CA, USA) with 36 pressure and 18 impedance segments. Data were analyzed for esophageal pressure topography and pressure‐flow analysis using custom Matlab analyses (Mathworks, Natick, USA). Paired t tests were performed with a P‐value of < .05 regarded as significant.
Key Results
Duration of bolus flow through (remifentanil/R 3.0±0.3 vs baseline/B 5.0 ± 0.4 seconds; P < .001) and presence at the EGJ (R 5.1 ± 0.5 vs B 7.1 ± 0.5 seconds; P = .001) both decreased during remifentanil administration. Distal latency (R 5.2 ± 0.4 vs B 7.5 ± 0.2 seconds; P < .001) and distal esophageal distension‐contraction latency (R 3.5 ± 0.1 vs B 4.7 ± 0.2 seconds; P < .001) were both reduced. Intrabolus pressures were increased in both the proximal (R 5.3 ± 0.9 vs B 2.6 ± 1.3 mm Hg; P = .01) and distal esophagus (R 8.6 ± 1.7 vs B 3.1 ± 0.8 mm Hg; P = .001). There was no evidence of increased esophageal bolus residue.
Conclusions and Inferences
Remifentanil‐induced effects were different for proximal and distal esophagus, with a reduced time for trans‐sphincteric bolus flow at the EGJ, suggestive of central and peripheral μ‐opioid agonism. There were no functional consequences in healthy subjects
Evidence of sensory-driven behavior in the Ediacaran organism Parvancorina: Implications and autecological interpretations
Get PDF© 2017 International Association for Gondwana Research. Published by Elsevier B.V.. This manuscript version is made available under the CC-BY-NC-ND 4.0 license: http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 12 month embargo from date of publication (Dec 2017) in accordance with the publisher’s archiving policyThe ancient in situ fossil seafloor communities of the Ediacara biota present an unparalleled window into the assembly of the earliest complex macroscopic organisms, including early animals on Earth ca. 555 million years ago (mya). The unique preservation style of Ediacara fossil seafloors preserves whole communities virtually ‘frozen in time’, including both living and dead organisms at the time of burial. This phenomenon, where the fossilized organisms are arranged as they were in life offers an unparalleled opportunity to examine ecological patterns in some of the earliest examples of animal communities in deep time. The small, anchor-shaped fossil genus Parvancorina is common among the Ediacara biota; however, its morphology and ecology have received little attention. Here, we describe a population of juvenile Parvancorina preserved on a section of fossil seafloor recently excavated from the characteristic Ediacara Member from Ediacara Conservation Park in the Flinders Ranges, South Australia. We applied spatial methods to the sample population of Parvancorina (n = 202) and found that they demonstrated two size-clusters, distinguishing juveniles from adults, and further analyses showed that the smaller specimens tended to be spatially aggregated. For the first time among any Ediacara taxon, we found that this sample population of Parvancorina demonstrated a strong bimodal orientation, suggesting that orientation played an important behavioral role in its autecology. The aggregated spatial distribution and bimodal orientation of Parvancorina likely resulted from behavioral responses to the influence of benthic currents, suggesting that Parvancorina had a complex sensory network, and was capable of motility
The role of Rhytidoponera metallica (Hymenoptera, Formicidae) in facilitating post-fire seed germination of three ant-dispersed legume species
Get PDFThis article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for self-archiving.The fire avoidance hypothesis proposes that a benefit of seed dispersal by ants (myrmecochory) is to
protect seeds from being killed during fire and to facilitate post-fire germination of seeds that require heat shock
to break their physical dormancy. The aim of this study was to quantify the effect of fire and seed burial by a
predominant seed-dispersing ant, Rhytidoponera metallica (subfamily: Ectatomminae) on germination levels of
three ant-dispersed legume species (Pultenaea daphnoides, Acacia myrtifolia and Acacia pycnantha). Experimental
burial of seeds within aluminium cans at a site prior to being burnt and at an adjacent unburnt site showed that
fire increased germination levels, particularly for seeds buried at 1- and 2-cm deep and that overall, germination
levels differed among the three plant species. To quantify seed burial depths and post-fire germination levels
facilitated by R. metallica ants, seeds were fed to colonies prior to fire at the burnt and unburnt sites. Of the
seeds buried within nests that were recovered, between 45% and 75% occurred within the upper 6 cm of the soil
profile, although unexpectedly, greater percentages of seeds were recovered from the upper 0–2 cm of nests in
the unburnt site compared with nests in the burnt site. Germination levels of buried seeds associated with
R. metallica nests ranged from 21.2% to 29.5% in the burnt site compared with 3.1–14.8% in the unburnt site.
While increased seed germination levels were associated with R. metallica nests following fire, most seeds were
buried at depths below those where optimal temperatures for breaking seed dormancy occurred during the fire.
We suggest that R. metallica ants may provide fire avoidance benefits to myrmecochorous seeds by burying them
at a range of depths within a potential germination zone defined by intra- and inter-fire variation in levels of soil
heating.This research was funded by the Wildlife Conservation
Fund, the Native Vegetation Council of South
Australia and the Mark Mitchell Research Foundation
Junior doctors’ preparedness to prescribe, monitor, and treat patients with the antibiotic vancomycin in an Australian teaching hospital
Get PDFThis is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Purpose
We aimed to assess the preparedness of junior doctors to use vancomycin, and to determine whether attending an educational session and being provided pocket guidelines were associated with self-reported confidence and objective knowledge.
Methods
This was a 2-component cross-sectional study. A 60-minute educational session was implemented and pocket guidelines were provided. Preparedness was evaluated by a self-reported confidence survey in the early and late stages of each training year, and by continuing medical education (CME) knowledge scores.
Results
Self-confidence was higher among those later in the training year (n=75) than in those earlier (n=120) in the year for all questions. In the late group, vancomycin education was associated with higher self-confidence regarding the frequency of therapeutic drug monitoring (P=0.02) and dose amendment (P=0.05); however, the confidence for initial monitoring was lower (P<0.05). Those with pocket guidelines were more confident treating patients with vancomycin (P<0.001), choosing initial (P=0.01) and maintenance doses (P<0.001), and knowing the monitoring frequency (P=0.03). The 85 respondents who completed the knowledge assessment scored a mean±standard deviation of 8.55±1.55 on 10 questions, and the interventions had no significant effect.
Conclusion
Attending an educational session and possessing pocket guidelines were associated with preparedness, as measured by higher self-reported confidence using vancomycin. High knowledge scores were attained following CME; however attending an educational session or possessing pocket guidelines did not significantly increase the knowledge scores. Our findings support providing educational sessions and pocket guidelines to increase self-confidence in prescribing vancomycin, yet also highlight the importance of evaluating content, format, and delivery when seeking to improve preparedness to use vancomycin through education
Legionella Persistence in Manufactured Water Systems: Pasteurization Potentially Selecting for Thermal Tolerance
Get PDFThis is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.Legionella is an opportunistic waterborne pathogen of increasing public health significance. Pasteurization, otherwise known as super-heat and flush (increasing water temperature to above 70°C and flushing all outlets), has been identified as an important mechanism for the disinfection of Legionella in manufactured water systems. However, several studies have reported that this procedure was ineffective at remediating water distribution systems as Legionella was able to maintain long term persistent contamination. Up to 25% of L. pneumophila cells survived heat treatment of 70°C, but all of these were in a viable but non-culturable state. This demonstrates the limitations of the culture method of Legionella detection currently used to evaluate disinfection protocols. In addition, it has been demonstrated that pasteurization and nutrient starvation can select for thermal tolerant strains, where L. pneumophila was consistently identified as having greater thermal tolerance compared to other Legionella species. This review demonstrates that further research is needed to investigate the effectiveness of pasteurization as a disinfection method. In particular, it focuses on the potential for pasteurization to select for thermal tolerant L. pneumophila strains which, as the primary causative agent of Legionnaires disease, have greater public health significance compared to other Legionella species
The Short and Long of Adolescent Sleep: The Unique Impact of Day Length
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This author accepted manuscript is made available following 12 month embargo from date of publication (July 2017) in accordance with the publisher’s archiving policyStudy objectives
Variation in day length is proposed to impact sleep, yet it is unknown whether this is above the influence of behavioural factors. Day length, sleep hygiene, and parent-set bedtime were simultaneously explored, to investigate the relative importance of each on adolescents’ sleep.
Methods
An online survey was distributed in four countries at varying latitudes/longitudes (Australia, The Netherlands, Canada, Norway).
Results
Overall, 711 (242 male; age M = 15.7 ± 1.6, range = 12–19 yrs) adolescents contributed data. Hierarchical regression analyses showed good sleep hygiene was associated with earlier bedtime, shorter sleep latency, and longer sleep (β = −0.34; −0.30; 0.32, p < 0.05, respectively). Shorter day length predicted later bedtime (β = 0.11, p = 0.009), decreased sleep latency (β = −0.21, p < 0.001), and total sleep (β = −0.14, p = 0.001). Longer day length predicted earlier bedtimes (β = −0.11, p = 0.004), and longer sleep (β = 0.10, p = 0.011).
Conclusions
Sleep hygiene had the most clinical relevance for improving sleep, thus should be considered when implementing adolescent sleep interventions, particularly as small negative effects of shorter day length may be minimised through sleep hygiene techniques
Relationship between Vascular Resistance and Sympathetic Nerve Fiber Density in Arterial Vessels in Children With Sleep Disordered Breathing
Get PDFPublished on behalf of the American Heart Association, Inc., by Wiley. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.Background Sleep disordered breathing in children is associated with increased blood flow velocity and sympathetic overactivity. Sympathetic overactivity results in peripheral vasoconstriction and reduced systemic vascular compliance, which increases blood flow velocity during systole. Augmented blood flow velocity is recognized to promote vascular remodeling. Importantly, increased vascular sympathetic nerve fiber density and innervation in early life plays a key role in the development of early‐onset hypertension in animal models. Examination of sympathetic nerve fiber density of the tonsillar arteries in children undergoing adenotonsillectomy for Sleep disordered breathing will address this question in humans.
Methods and Results Thirteen children scheduled for adenotonsillectomy to treat sleep disordered breathing underwent pupillometry, polysomnography, flow‐mediated dilation, resting brachial artery blood flow velocity (velocity time integral), and platelet aggregation. The dorsal lingual artery (tonsil) was stained and immunofluorescence techniques used to determine sympathetic nerve fiber density. Sympathetic nerve fiber density was correlated with increased resting velocity time integral (r=0.63; P<0.05) and a lower Neuronal Pupillary Index (r=−0.71, P<0.01), as well as a slower mean pupillary constriction velocity (mean, r=−0.64; P<0.05). A faster resting velocity time integral was associated with a slower peak pupillary constriction velocity (r=−0.77; P<0.01) and higher platelet aggregation to collagen antigen (r=0.64; P<0.05). Slower mean and peak pupillary constriction velocity were associated with higher platelet aggregation scores (P<0.05; P<0.01, respectively).
Conclusions These results indicate that sympathetic activity is associated with change in both the function and structure of systemic vasculature in children with sleep disordered breathing
Patterns of participation over four rounds of annual fecal immunochemical test-based screening for colorectal cancer: what predicts rescreening?
Get PDFThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Background
Participation at the recommended intervals is critical for screening to be effective in reducing colorectal cancer (CRC) incidence. This study describes patterns of screening participation over four rounds of fecal immunochemical testing (FIT) to identify whether demographic variables and prior screening satisfaction are significantly associated with patterns of re-participation.
Methods
Baseline surveys were mailed to 4000 South Australians randomly selected from the electoral-roll. Respondents (n = 1928/48.2%) were offered four annual FIT rounds. Screening participation and satisfaction at each round were recorded.
Results
Study participation was 58.5, 66.9, 73.1 and 71.4% respectively over four rounds. Three participation patterns were described: consistent participation (43.1%), consistent non-participation (26.4%) and inconsistent participation (changeable; 30.5%), including intermittent and sustained change patterns. Sustained change described those who changed participatory behavior and then maintained for at least two rounds (n = 375/19.5%). Older people, and those not working were most likely to sustain participation. Younger invitees, especially men, were more likely to change participatory behavior and sustain the change. People with higher disadvantage, less education, not working and with no prior (pre-trial) screening experience were more likely to start participating and drop out. People dissatisfied with a prior screening test, including finding aspects embarrassing or unpleasant, were also more likely not to participate in annual screening or to drop out.
Conclusions
The findings identify those at risk of non- or inconsistent participation in rescreening. They should aid targeting of interventions for demographic groups at risk and ensuring screening experiences are not perceived as unpleasant or difficult