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    The psychometric properties and minimal clinically important difference for disability assessment using WHODAS 2.0 in critically ill patients
    Higgins, AM ; Neto, AS ; Bailey, M ; Barrett, J ; Bellomo, R ; Cooper, DJ ; Gabbe, B ; Linke, N ; Myles, PS ; Paton, M ; Philpot, S ; Shulman, M ; Young, M ; Hodgson, CL (AUSTRALASIAN MED PUBL CO LTD, 2021-03)
    Objectives: The 12-item World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) provides a standardised method for measuring health and disability. This study aimed to determine its reliability, validity and responsiveness and to establish the minimum clinically important difference (MCID) in critically ill patients. Design: Prospective, multicentre cohort study. Setting: Intensive care units of six metropolitan hospitals. Participants: Adults mechanically ventilated for > 24 hours. Main outcome measures: Reliability was assessed by measuring internal consistency. Construct validity was assessed by comparing WHODAS 2.0 scores at 6 months with the EuroQoL visual analogue scale (EQ VAS) and Lawton Instrumental Activities of Daily Living (IADL) scale scores. Responsiveness was evaluated by assessing change over time, effect sizes, and percentage of patients showing no change. The MCID was calculated using both anchor and distribution-based methods with triangulation of results. Main results: A baseline and 6-month WHODAS 2.0 score were available for 448 patients. The WHODAS 2.0 demonstrated good correlation between items with no evidence of item redundancy. Cronbach α coefficient was 0.91 and average split-half coefficient was 0.91. There was a moderate correlation between the WHODAS 2.0 and the EQ VAS scores (r = -0.72; P < 0.001) and between the WHODAS 2.0 and the Lawton IADL scores (r = -0.66; P < 0.001) at 6 months. The effect sizes for change in the WHODAS 2.0 score from baseline to 3 months and from 3 to 6 months were low. Ceiling effects were not present and floor effects were present at baseline only. The final MCID estimate was 10%. Conclusion: The 12-item WHODAS 2.0 is a reliable, valid and responsive measure of disability in critically ill patients. A change in the total WHODAS 2.0 score of 10% represents the MCID.
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    Knowledge, confidence, attitudes and beliefs of physiotherapists and physiotherapy students working with people with dementia: A mixed-methods systematic review
    Quick, S ; Snowdon, DA ; Lawler, K ; McGinley, J ; Soh, SE ; Callisaya, ML (Wiley, 2021-12-01)
    BACKGROUND: Clinical care for people with dementia as a primary diagnosis, or as a co-morbidity, can be complex. Physiotherapists play a key role in the care of people living with dementia in multiple settings. The aim of this systematic review is to understand the attitudes, beliefs, knowledge and confidence of physiotherapists and physiotherapy students when working with people with dementia. METHOD: This was a mixed-methods systematic review that included qualitative and quantitative studies. Participants were physiotherapists working in any clinical specialty (e.g. gerontology, orthopaedic, neurological, cardio-respiratory), and physiotherapy students who had completed at least one clinical placement. If studies investigated physiotherapist and physiotherapy students' knowledge, confidence, attitudes or beliefs on working with a general population of older adults, they were excluded. The phenomena of interest and context were attitudes, beliefs, knowledge and confidence when working with people with dementia in any setting. Eleven databases were searched. Data synthesis followed a convergent integrated approach according to Joanna Briggs Institute methodology for mixed methods systematic reviews. RESULT: 15 studies were eligible for inclusion (9 quantitative and 6 qualitative studies). There were 5 key themes: rehabilitation potential (variable outcomes, poor potential), challenges in dementia care (communication, behaviour, cognition, risk, stress and burnout), education in dementia practice (inadequate training and knowledge, importance of experience), specialised area of practice (complexity of presentation, nuance of care, importance of time, holistic approach) and unsupportive systems (environment, time, risk aversion). One code, lack of desire to provide dementia care, did not contribute to any themes. CONCLUSION: Physiotherapists and physiotherapy students have low levels of knowledge and confidence in several areas important to working with people with dementia. With higher levels of knowledge and confidence associated with more positive attitudes and beliefs, dementia education needs of physiotherapists at all levels needs to be addressed.
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    Mof (MYST1 or KAT8) is essential for progression of embryonic development past the blastocyst stage and required for normal chromatin architecture
    Thomas, T ; Dixon, MP ; Kueh, AJ ; Voss, AK (AMER SOC MICROBIOLOGY, 2008-08)
    Acetylation of histone tails is a hallmark of transcriptionally active chromatin. Mof (males absent on the first; also called MYST1 or KAT8) is a member of the MYST family of histone acetyltransferases and was originally discovered as an essential component of the X chromosome dosage compensation system in Drosophila. In order to examine the role of Mof in mammals in vivo, we generated mice carrying a null mutation of the Mof gene. All Mof-deficient embryos fail to develop beyond the expanded blastocyst stage and die at implantation in vivo. Mof-deficient cell lines cannot be derived from Mof(-/-) embryos in vitro. Mof(-/-) embryos fail to acetylate histone 4 lysine 16 (H4K16) but have normal acetylation of other N-terminal histone lysine residues. Mof(-/-) cell nuclei exhibit abnormal chromatin aggregation preceding activation of caspase 3 and DNA fragmentation. We conclude that Mof is functionally nonredundant with the closely related MYST histone acetyltransferase Tip60. Our results show that Mof performs a different role in mammals from that in flies at the organism level, although the molecular function is conserved. We demonstrate that Mof is required specifically for the maintenance of H4K16 acetylation and normal chromatin architecture of all cells of early male and female embryos.
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    Gata-3 Negatively Regulates the Tumor-Initiating Capacity of Mammary Luminal Progenitor Cells and Targets the Putative Tumor Suppressor Caspase-14
    Asselin-Labat, M-L ; Sutherland, KD ; Vaillant, F ; Gyorki, DE ; Wu, D ; Holroyd, S ; Breslin, K ; Ward, T ; Shi, W ; Bath, ML ; Deb, S ; Fox, SB ; Smyth, GK ; Lindeman, GJ ; Visvader, JE (AMER SOC MICROBIOLOGY, 2011-11)
    The transcription factor Gata-3 is a definitive marker of luminal breast cancers and a key regulator of mammary morphogenesis. Here we have explored a role for Gata-3 in tumor initiation and the underlying cellular mechanisms using a mouse model of "luminal-like" cancer. Loss of a single Gata-3 allele markedly accelerated tumor progression in mice carrying the mouse mammary tumor virus promoter-driven polyomavirus middle T antigen (MMTV-PyMT mice), while overexpression of Gata-3 curtailed tumorigenesis. Through the identification of two distinct luminal progenitor cells in the mammary gland, we demonstrate that Gata-3 haplo-insufficiency increases the tumor-initiating capacity of these progenitors but not the stem cell-enriched population. Overexpression of a conditional Gata-3 transgene in the PyMT model promoted cellular differentiation and led to reduced tumor-initiating capacity as well as diminished angiogenesis. Transcript profiling studies identified caspase-14 as a novel downstream target of Gata-3, in keeping with its roles in differentiation and tumorigenesis. A strong association was evident between GATA-3 and caspase-14 expression in preinvasive ductal carcinoma in situ samples, where GATA-3 also displayed prognostic significance. Overall, these studies identify GATA-3 as an important regulator of tumor initiation through its ability to promote the differentiation of committed luminal progenitor cells.
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    A multicentre point prevalence study of delirium assessment and management in patients admitted to Australian and New Zealand intensive care units
    Ankravs, MJ ; Udy, AA ; Byrne, K ; Knowles, S ; Hammond, N ; Saxena, MK ; Reade, MC ; Bailey, M ; Bellomo, R ; Deane, AM (AUSTRALASIAN MED PUBL CO LTD, 2020-12)
    Objective: To characterise the assessment and management of delirium in patients admitted to intensive care units (ICUs) in Australia and New Zealand. Methods: We conducted a multicentre observational point prevalence study across 44 adult Australian and New Zealand ICUs. Data were extracted for all patients in the ICU in terms of assessment and treatment of delirium. ICU-level data were collected regarding the use of explicit protocols related to delirium. Results: We studied 627 patients, with 54% (336/627) having at least one delirium screening assessment performed. The Confusion Assessment Method for the ICU (CAM-ICU) was the most frequently used tool (88%, 296/336). Of patients assessed, 20% (68) were identified to have delirium. Eighteen per cent (111) of patients were administered a drug to manage delirium, with 41% (46) of those receiving a drug having no recorded assessment for delirium on that day. Of the drugs used to treat delirium, quetiapine was the most frequently administered. Physical restraints were applied to 8% (48/626) of patients, but only 17% (8/48) of such patients had been diagnosed with delirium. Most physically restrained patients either did not have delirium diagnosed (31%, 15/48) or had no formal assessment recorded (52%, 25/48) on that day. Conclusions: On the study day, more than 50% of patients had a delirium screening assessment performed, with 20% of screened patients deemed to have delirium. Drugs that are prescribed to treat delirium and physical restraints were frequently used in the absence of delirium or the formal assessment for its presence.
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    Replication: Belief elicitation with quadratic and binarized scoring rules
    Erkal, N ; Gangadharan, L ; Koh, BH (Elsevier, 2020-12-01)
    Researchers increasingly elicit beliefs to understand the underlying motivations of decision makers. Two commonly used methods are the quadratic scoring rule (QSR) and the binarized scoring rule (BSR). Hossain and Okui (2013) use a within-subject design to evaluate the performance of these two methods in an environment where subjects report probabilistic beliefs over binary outcomes with objective probabilities. In a near replication of their study, we show that their results continue to hold with a between-subject design. This is an important validation of the BSR given that researchers typically implement only one method to elicit beliefs. In favor of the BSR, reported beliefs are less accurate under the QSR than the BSR. Consistent with theoretical predictions, risk-averse subjects distort their reported beliefs under the QSR.
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    Proteome reprogramming of endometrial epithelial cells by human trophectodermal small extracellular vesicles reveals key insights into embryo implantation
    Poh, QH ; Rai, A ; Carmichael, II ; Salamonsen, LA ; Greening, DW (WILEY, 2021-07)
    Embryo implantation into the receptive endometrium is critical in pregnancy establishment, initially requiring reciprocal signalling between outer layer of the blastocyst (trophectoderm cells) and endometrial epithelium; however, factors regulating this crosstalk remain poorly understood. Although endometrial extracellular vesicles (EVs) are known to signal to the embryo during implantation, the role of embryo-derived EVs remains largely unknown. Here, we provide a comprehensive proteomic characterisation of a major class of EVs, termed small EVs (sEVs), released by human trophectoderm cells (Tsc-sEVs) and their capacity to reprogram protein landscape of endometrial epithelium in vitro. Highly purified Tsc-sEVs (30-200 nm, ALIX+ , TSG101+ , CD9/63/81+ ) were enriched in known players of implantation (LIFR, ICAM1, TAGLN2, WNT5A, FZD7, ROR2, PRICKLE2), antioxidant activity (SOD1, PRDX1/4/6), tissue integrity (EZR, RAC1, RHOA, TNC), and focal adhesions (FAK, ITGA2/V, ITGB1/3). Functionally, Tsc-sEVs were taken up by endometrial cells, altered transepithelial electrical resistance, and upregulated proteins implicated in embryo attachment (ITGA2/V, ITGB1/3), immune regulation (CD59, CD276, LGALS3), and antioxidant activity (GPX1/3/4, PRDX1/2/4/5/6): processes that are critical for successful implantation. Collectively, we provide critical insights into Tsc-sEV-mediated regulation of endometrial function that contributes to our understanding of the molecular basis of implantation.
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    Impact of chemically defined culture media formulations on extracellular vesicle production by amniotic epithelial cells
    Zhu, D ; Fang, H ; Kusuma, GD ; Schwab, R ; Barabadi, M ; Chan, ST ; McDonald, H ; Leong, CM ; Wallace, EM ; Greening, DW ; Lim, R (WILEY, 2021-07)
    The therapeutic properties of cell derived extracellular vesicles (EVs) make them promising cell-free alternative to regenerative medicine. However, clinical translation of this technology relies on the ability to manufacture EVs in a scalable, reproducible, and cGMP-compliant manner. To generate EVs in sufficient quantity, a critical step is the selection and development of culture media, where differences in formulation may influence the EV manufacturing process. In this study, we used human amniotic epithelial cells (hAECs) as a model system to explore the effect of different formulations of chemically defined, commercially sourced media on EV production. Here, we determined that cell viability and proliferation rate are not reliable quality indicators for EV manufacturing. The levels of tetraspanins and epitope makers of EVs were significantly impacted by culture media formulations. Mass spectrometry-based proteomic profiling revealed proteome composition of hAEC-EVs and the influence of media formulations on composition of EV proteome. This study has revealed critical aspects including cell viability and proliferation rate, EV yield, and tetraspanins, surface epitopes and proteome composition of EVs influenced by media formulations, and further insight into standardised EV production culture media that should be considered in clinical-grade scalable EV manufacture for generation of therapeutic EVs.
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    Mental Health
    Butterworth, P ; Poyser, C ; Suomi, A ; MCDONALD, SJ ; THOMPSON, CM (WILEY, 2021-12)
    Abstract Mental health has been a focus of over 200 journal articles using the HILDA Survey data. This brief review provides an overview of the mental health data collected through the HILDA Survey, and discusses the potential reasons why HILDA Survey data have been used so frequently in mental health research. We reflect on how the HILDA Survey data have: provided insights into the profile of mental health in the Australian community, illustrated the importance of social ties for mental health and enabled investigation of social inequalities in mental health.
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    Prolonged Eyelid Closure Episodes during Sleep Deprivation in Professional Drivers
    Alvaro, PK ; Jackson, ML ; Berlowitz, DJ ; Swann, P ; Howard, ME (AMER ACAD SLEEP MEDICINE, 2016)
    STUDY OBJECTIVES: Real life ocular measures of drowsiness use average blink duration, amplitude and velocity of eyelid movements to reflect drowsiness in drivers. However, averaged data may conceal the variability in duration of eyelid closure episodes, and more prolonged episodes that indicate higher levels of drowsiness. The current study aimed to describe the frequency and duration of prolonged eyelid closure episodes during acute sleep deprivation. METHODS: Twenty male professional drivers (mean age ± standard deviation = 41.9 ± 8.3 years) were recruited from the Transport Workers Union newsletter and newspaper advertisements in Melbourne, Australia. Each participant underwent 24 hours of sleep deprivation and completed a simulated driving task (AusEd), the Psychomotor Vigilance Task, and the Karolinska Sleepiness Scale. Eyelid closure episodes during the driving task were recorded and analyzed manually from digital video recordings. RESULTS: Eyelid closure episodes increased in frequency and duration with a median of zero s/h of eyelid closure after 3 h increasing to 34 s/h after 23 h awake. Eyelid closure episodes were short and infrequent from 3 to 14 h of wakefulness. After 17 h of sleep deprivation, longer and more frequent eyelid closure episodes began to occur. Episodes lasting from 7 seconds up to 18 seconds developed after 20 h of wakefulness. Length of eyelid closure episodes was moderately to highly correlated with the standard deviation of lateral lane position, braking reaction time, crashes, impaired vigilance, and subjective sleepiness. CONCLUSIONS: The frequency and duration of episodes of prolonged eyelid closure increases during acute sleep deprivation, with very prolonged episodes after 17 hours awake. Automated devices that assess drowsiness using averaged measures of eyelid closure episodes need to be able to detect prolonged eyelid closure episodes that occur during more severe sleep deprivation.