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How the chance of missing the alarm during an on-call shift affects pre-bed anxiety, sleep and next day cognitive performance
Get PDF© 2018 Elsevier. 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 (September 2018) in accordance with the publisher’s archiving policy.This study investigated how the likelihood of missing an alarm affects pre-bed anxiety, sleep and next
day cognitive performance during on-call shifts. Participants (n=24) completed one adaptation night,
one control night and two on-call nights in a time-isolated sleep laboratory. On one of the on-call
nights, participants were informed that they would be woken by a loud alarm that they would
definitely not be able to sleep through (low likelihood of missing the alarm). On the other on-call night,
participants were informed that they would be woken by a quiet alarm that they may sleep through
(high likelihood of missing the alarm). The two on-call nights were counterbalanced. Pre-bed anxiety
was measured using the State Trait Anxiety Inventory x-1, while sleep macro- and micro-architecture
was examined via routine polysomnography and power spectral analyses respectively. Following each
sleep, cognitive performance was assessed four times (0930, 1200, 1430, 1700) using the 10-min
psychomotor vigilance task (PVT). Results indicated that while pre-bed anxiety was similarly increased
during both high and low likelihood of missing the on-call alarm conditions compared with control,
only in the high likelihood condition was total sleep time shorter and sleep efficiency lower compared
with the control condition. However, more wake after sleep onset was found in the low likelihood
condition compared with control. PVT data indicate that response times (mean reciprocal and mean
fastest 10% of reaction time) were fastest in the low likelihood condition, indicating better
performance when compared with both other conditions. However, there were significantly more
lapses in the low likelihood condition compared with control. No significant EEG power spectral
differences were observed. As such, it appears that there are detrimental effects of both on-call
conditions on anxiety, sleep and performance, with sleep poorest when the likelihood of missing the
alarm is high. The adverse impacts on sleep and performance outcomes while on-call may be mitigated
by the implementation of workplace systems to reduce the likelihood of missing alarms (e.g., having
two available options for contacting on-call workers).This study was funded by an Australian Research Council Discovery grant (DP 150104497). Funding for Madeline Sprajcer’s PhD scholarship was provided by this grant. Dr Grace Vincent is supported by an Early Career Fellowship at Central Queensland University
New insights into the viscoelastic and failure mechanical properties of the elastic fiber network of the inter-lamellar matrix in the annulus fibrosus of the disc
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manuscript version is made available under the CC-BY-NCND
4.0 license:
http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 24 month embargo from date of publication (Sept 2020) in accordance with the publisher’s archiving policyThe mechanical role of elastic fibers in the inter-lamellar matrix (ILM) is unknown; however, it has been suggested that they play a role in providing structural integrity to the annulus fibrosus (AF). Therefore, the aim of this study was to measure the viscoelastic and failure properties of the elastic fiber network in the ILM of ovine discs under both tension and shear directions of loading. Utilizing a technique, isolated elastic fibers within the ILM from ovine discs were stretched to 40% of their initial length at three strain rates of 0.1% s−1 (slow), 1% s−1 (medium) and 10% s−1 (fast), followed by a ramp test to failure at 10% s−1. A significant strain-rate dependent response was found, particularly at the fastest rate for phase angle and normalized stiffness (p < 0.001). The elastic fibers in the ILM demonstrated a significantly higher capability for energy absorption at slow compared to medium and fast strain rates (p < 0.001). These finding suggests that the elastic fiber network of the ILM exhibits nonlinear elastic behavior. When tested to failure, a significantly higher normalized failure force was found in tension compared to shear loading (p = 0.011), which is consistent with the orthotropic structure of elastic fibers in the ILM. The results of this study confirmed the mechanical contribution of the elastic fiber network to the ILM and the structural integrity of the AF. This research serves as a foundation for future studies to investigate the relationship between degeneration and ILM mechanical properties
World Endoscopy Organization Consensus Statements on Post-Colonoscopy and Post-Imaging Colorectal Cancer
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made available 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.
This author accepted manuscript is made available following 12 month embargo from date of publication (June 2018) in accordance with the publisher’s archiving policyBackground & Aims
Colonoscopy examination does not always detect colorectal cancer (CRC)— some patients develop CRC after negative findings from an examination. When this occurs before the next recommended examination, it is called interval cancer. From a colonoscopy quality assurance perspective, that term is too restrictive, so the term post-colonoscopy colorectal cancer (PCCRC) was created in 2010. However, PCCRC definitions and methods for calculating rates vary among studies, making it impossible to compare results. We aimed to standardize the terminology, identification, analysis, and reporting of PCCRCs and CRCs detected after other whole-colon imaging evaluations (post-imaging colorectal cancers [PICRCs]).
Methods
A 20-member international team of gastroenterologists, pathologists, and epidemiologists; a radiologist; and a non-medical professional met to formulate a series of recommendations, standardize definitions and categories (to align with interval cancer terminology), develop an algorithm to determine most-plausible etiologies, and develop standardized methodology to calculate rates of PCCRC and PICRC. The team followed the Appraisal of Guidelines for Research and Evaluation II tool. A literature review provided 401 articles to support proposed statements; evidence was rated using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system. The statements were voted on anonymously by team members, using a modified Delphi approach.
Results
The team produced 21 statements that provide comprehensive guidance on PCCRCs and PICRCs. The statements present standardized definitions and terms, as well as methods for qualitative review, determination of etiology, calculation of PCCRC rates, and non-colonoscopic imaging of the colon.
Conclusions
A 20-member international team has provided standardized methods for analysis of etiologies of PCCRCs and PICRCs and defines its use as a quality indicator. The team provides recommendations for clinicians, organizations, researchers, policy makers, and patients
Validation of the Australian Midwifery Standards Assessment Tool (AMSAT): a tool to assess midwifery competence
Get PDF© 2017 Australian College of Midwives. Published by Elsevier Ltd. This author accepted manuscript is made available following 24 month embargo from date of publication (February 2018) in accordance with the publisher’s archiving policyBackground
There is no current validated clinical assessment tool to measure the attainment of midwifery student competence in the midwifery practice setting. The lack of a valid assessment tool has led to a proliferation of tools and inconsistency in assessment of, and feedback on student learning.
Objective
This research aimed to develop and validate a tool to assess competence of midwifery students in practice-based settings.
Design
A mixed-methods approach was used and the study implemented in two phases. Phase one involved the development of the AMSAT tool with qualitative feedback from midwifery academics, midwife assessors of students, and midwifery students. In phase two the newly developed AMSAT tool was piloted across a range of midwifery practice settings and ANOVA was used to compare scores across year levels, with feedback being obtained from assessors.
Findings
Analysis of 150 AMSAT forms indicate the AMSAT as: reliable (Cronbach alpha greater than 0.9); valid—data extraction loaded predominantly onto one factor; and sensitivity scores indicating level of proficiency increased across the three years. Feedback evaluation forms (n = 83) suggest acceptance of this tool for the purpose of both assessing and providing feedback on midwifery student’s practice performance and competence.
Conclusion
The AMSAT is a valid, reliable and acceptable midwifery assessment tool enables consistent assessment of midwifery student competence. This assists benchmarking across midwifery education programs
Effects of Genetic Variation in Protease Activated Receptor 4 after an Acute Coronary Syndrome: Analysis from the TRACER trial
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available under the CC-BY-NC-ND 4.0 license:
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This author accepted manuscript is made available following 12 month embargo from date of publication (Sept 2018) in accordance with the publisher’s archiving policyVariation in platelet response to thrombin may affect the safety and efficacy of PAR antagonism. The Thr120 variant of the common single nucleotide polymorphism (SNP) rs773902 in the protease-activated receptor (PAR) 4 gene is associated with higher platelet aggregation compared to the Ala120 variant. We investigated the relationship between the rs773902 SNP with major bleeding and ischemic events, safety, and efficacy of PAR1 inhibition in 6177 NSTE ACS patients in the TRACER trial. There was a lower rate of GUSTO moderate/severe bleeding in patients with the Thr120 variant. The difference was driven by a lower rate in the smaller homozygous group (recessive model, HR 0.13 [0.02–0.92] P = 0.042). No significant differences were observed in the ischemic outcomes. The excess in bleeding observed with PAR1 inhibition was attenuated in patients with the Thr120 variant, but the interactions were not statistically significant. In summary, lower major bleeding rates were observed in the overall TRACER cohort with the hyperreactive PAR4 Thr120 variant. The increase in bleeding with vorapaxar was attenuated with the Thr120 variant, but we could not demonstrate an interaction with PAR1 inhibition. These findings warrant further exploration, including those of African ancestry where the A allele (Thr120) frequency is ~65%.This work was supported by the National Institutes of Health [grant number HL102482]; the University of Utah Division of Hematology and Hematologic Malignancies; and the Cardeza Foundation for Hematologic Research
Unravelling the association between inhibitory control and loss of control over eating among adolescents
Get PDF© 2017 Elsevier. 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 24 month embargo from date of publication (Feb 2018) in accordance with the publisher’s archiving policyObjective
Loss of control over eating is common among adolescents and is associated with negative developmental outcomes. Recent evidence points to impaired self-regulation, and more specifically poor inhibitory control, as a contributing factor to loss of control over eating among adults; however evidence in adolescent samples is limited. Moreover, in line with dual-process models, researchers have recently started to investigate the moderating role of automatic processes in this relationship, but again studies in adolescents are lacking. Therefore, the aim of the current study was to: (1) investigate whether there is an association between poor inhibitory control and loss of control over eating also among adolescents, and (2) explore whether this relationship is moderated by automatic processing.
Method
A community sample of 124 adolescents (10–17 years; 65.3% girls; Mage = 14 years; SD = 1.90) was divided into a ‘Loss of Control Group’ (n = 30) and a ‘No Loss of Control Group’ (n = 94) based on a clinical interview. Inhibitory control and automatic processing (general and food specific) were measured by self-report questionnaires.
Results
Adolescents in the Loss of Control Group reported significantly more problems with overall self-regulation compared to the No Loss of Control Group; however, there was no group difference for inhibition specifically. Contrary to dual-process predictions, there was a trend significant interaction between poor inhibitory control and weaker food specific automatic processing in explaining loss of control over eating.
Conclusions
Evidence was found for problems with overall self-regulation in adolescents with loss of control over eating. Concerning the specific role of inhibitory control, future studies should replicate whether automatic processing is indeed a crucial moderator
Letter to the Editor: Metacognitive training and metacognitive therapy. A reply to Lora Capobianco and Adrian Wells
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This author accepted manuscript is made available following 24 month embargo from date of publication (Jan 2018) in accordance with the publisher’s archiving policyTo the Editor: It is indeed unfortunate that our metacognitive treatment programs use a similar name as the psychotherapy developed by Adrian Wells. Nevertheless, we believe that our use of the term ‘metacognitive’ is justified.
The term ‘metacognition’ is somewhat over-inclusive. Coined by Flavell (1979) it is usually understood as “thinking about one's thinking”. Yet, subsequent research used the term in various ways (Koriat, 2002). For example, confidence/doubt is at the heart of metacognition according to Asher Koriat (Koriat & Levy-Sadot, 1999). In neuropsychology, a discrepancy between subjective and objective performance is termed a deficit in metacognition (for an early study see Anderson-Parenté, 1994). Moreover, Flavell's definition of metacognitive knowledge about oneself versus others is quite close to the concept of social cognition, further blurring the boundaries (p. 906).
The idea for metacognitive training for psychosis originated in the early 2000s based on research suggesting ‘cognitive biases’ in people with psychosis (Garety & Freeman, 1999), such as jumping to conclusions (JTC), incorrigibility and overconfidence (note that these are not “thought contents” as Capobianco and Wells write, but rather overarching distortions in the processing of information; see Pohl, 2004). Importantly, awareness of these biases is poor in many patients. The primary goal of our approach was to ‘straighten’ these cognitive biases (not to be confused with emotional distortions/biases proposed by Aaron Beck) and raise metacognitive awareness in a gentle, non-confrontational manner (e.g., through playful exercises that generate surprising outcomes [i.e., metacognitive experience] and through education regarding cognitive biases [i.e., metacognitive knowledge]). A recurring theme in MCT for psychosis is that patients should check whether their confidence in a given judgment is justified (metacognitive strategy, cf. Koriat, 2002) and to “sow the seeds of doubt”.
Importantly, MCT exercises on cognitive biases use delusion-neutral material. Although the ultimate goal is to improve delusions, this is achieved indirectly, as the main emphasis of the intervention remains on the modification at a meta-level of processing (e.g., confidence in judgements). We therefore reject the claim by Capobianco and Wells that our program “is clearly a cognitive behavioral approach that deals with the content of negative thoughts."
Over the years, we incorporated compatible elements from CBT, while the focus remained on metacognition. Why did we do this? Initially, we had the perhaps naive hope that our MCT would run alongside other psychotherapeutic programs in mental health institutions. However, as the literature shows, psychotherapy for psychosis is rarely provided. In order to address this problem within our low-threshold program, the newest versions of MCT and MCT + include additional modules with a CBT orientation, dealing with issues deemed by patients to be a priority in treatment, namely self-esteem and stigma. We have devised a number of MCT interventions for other disorders, which are clearly rooted in the setup and presentation mode of MCT for psychosis. These disorder-specific versions were developed as hybrids to amalgamate a cognitive and a metacognitive perspective, as we do not view working on a cognitive or metacognitive level as mutually exclusive.
Wells' work dates back to the 1990s - however, to the best of our knowledge, the term ‘metacognitive therapy’ was introduced much later. When we became aware of its existence, MCT for psychosis was already available and used in many different languages (currently 33 languages). Therefore, changing its name would have created new confusion; however, we used slightly different names or acronyms (e.g., myMCT) to distinguish the two approaches
Late characterisation of cardiac effects following anthracycline and trastuzumab treatment in breast cancer patients
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This author accepted manuscript is made available following 12 month embargo from date of publication (March 2018) in accordance with the publisher’s archiving policyBackground
Anthracycline (A) and trastuzumab (T) chemotherapy have well-recognized cardiac toxicity, potentially leading to significant morbidity and mortality. Our previous work in 46 prospectively enrolled breast cancer patients showed early left ventricular (LV) and right ventricular (RV) function decline at 1 and 3 months, but only persistent RV dysfunction at 12 months which correlated with myocardial oedema observed early (1 and 3 months) after administration of chemotherapy regimes.
Method
To investigate late cardiac effects, the same cohort were re-imaged with advanced Cardiovascular Magnetic Resonance (CMR) imaging including T1 mapping 5 ± 1 year post chemotherapy.
Results
Twenty-six out of 46 (50%) patients underwent follow-up imaging. A statistical but non-clinically significant decrease was observed in LV ejection fraction (EF) from baseline to 5 years (72.2 ± 6.6 to 65.4 ± 9.3, p 10% at 3 months (n = 5) or at 12 months (n = 3) did not demonstrate any difference in LV or RVEF at 5 years. No correlation was observed between myocardial oedema and LV or RVEF at 5 years. At 5 years, T1 values were within normal limits overall (935 ± 48 ms). One patients had significantly elevated (>1000 ms) T1 values with no correlation to LV or RVEF. No subjects demonstrated replacement myocardial fibrosis at 5 years.
Conclusion
Using advanced CMR, contemporary chemotherapy regimes demonstrate minimal long-term cardiac toxicity. There is minimal diffuse and no replacement fibrosis as demonstrated by LGE, following chemotherapy. This study suggests limiting serial imaging in these patients at 12 months post chemotherapy
New findings confirm the viscoelastic behaviour of the inter-lamellar matrix of the disc annulus fibrosus in radial and circumferential directions of loading
Get PDF© 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. 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 24 month embargo from date of publication (March 2018) in accordance with the publisher’s archiving policyWhile few studies have improved our understanding of composition and organization of elastic fibres in the inter-lamellar matrix (ILM), its clinical relevance is not fully understood. Moreover, no studies have measured the direct tensile and shear failure and viscoelastic properties of the ILM. Therefore, the aim of this study was, for the first time, to measure the viscoelastic and failure properties of the ILM in both the tension and shear directions of loading. Using an ovine model, isolated ILM samples were stretched to 40% of their initial length at three strain rates of 0.1%s−1 (slow), 1%s−1 (medium) and 10%s−1 (fast) and a ramp test to failure was performed at a strain rate of 10%s−1. The findings from this study identified that the stiffness of the ILM was significantly larger at faster strain rates, and energy absorption significantly smaller, compared to slower strain rates, and the viscoelastic and failure properties were not significantly different under tension and shear loading. We found a strain rate dependent response of the ILM during dynamic loading, particularly at the fastest rate. The ILM demonstrated a significantly higher capability for energy absorption at slow strain rates compared to medium and fast strain rates. A significant increase in modulus was found in both loading directions and all strain rates, having a trend of larger modulus in tension and at faster strain rates. The finding of no significant difference in failure properties in both loading directions, was consistent with our previous ultra-structural studies that revealed a well-organized (±45°) elastic fibre orientation in the ILM. The results from this study can be used to develop and validate finite element models of the AF at the tissue scale, as well as providing new strategies for fabricating tissue engineered scaffolds.
Statement of significance
While few studies have improved our understanding of composition and organization of elastic fibres in the inter-lamellar matrix (ILM) of the annulus in the disc no studies have measured the direct mechanical failure and viscoelastic properties of the ILM. The findings from this study identified that the stiffness of the ILM was significantly larger at faster strain rates, and energy absorption significantly smaller, compared to slower strain rates. The failure properties of the ILM were not significantly different under tension and shear
Delivery of siRNA in vitro and in vivo using PEI-capped porous silicon nanoparticles to silence MRP1 and inhibit proliferation in glioblastoma
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Background
Multidrug resistance-associated protein 1 (MRP1) overexpression plays a major role in chemoresistance in glioblastoma multiforme (GBM) contributing to its notorious deadly nature. Although MRP1-siRNA transfection to GBM in vitro has been shown to sensitise the cells to drug, MRP1 silencing in vivo and the phenotypic influence on the tumour and normal tissues upon MRP1 down-regulation have not been established. Here, porous silicon nanoparticles (pSiNPs) that enable high-capacity loading and delivery of siRNA are applied in vitro and in vivo.
Result
We established pSiNPs with polyethyleneimine (PEI) capping that enables high-capacity loading of siRNA (92 µg of siRNA/mg PEI-pSiNPs), and optimised release profile (70% released between 24 and 48 h). These pSiNPs are biocompatible, and demonstrate cellular uptake and effective knockdown of MRP1 expression in GBM by 30%. Also, siRNA delivery was found to significantly reduce GBM proliferation as an associated effect. This effect is likely mediated by the attenuation of MRP1 transmembrane transport, followed by cell cycle arrest. MRP1 silencing in GBM tumour using MRP1-siRNA loaded pSiNPs was demonstrated in mice (82% reduction at the protein level 48 h post-injection), and it also produced antiproliferative effect in GBM by reducing the population of proliferative cells. These results indicate that in vitro observations are translatable in vivo. No histopathological signs of acute damage were observed in other MRP1-expressing organs despite collateral downregulations.
Conclusions
This study proposes the potential of efficient MRP1-siRNA delivery by using PEI-capped pSiNPs in achieving a dual therapeutic role of directly attenuating the growth of GBM while sensitising residual tumour cells to the effects of chemotherapy post-resection