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ItemNo Preview AvailableGata-3 Negatively Regulates the Tumor-Initiating Capacity of Mammary Luminal Progenitor Cells and Targets the Putative Tumor Suppressor Caspase-14(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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ItemNo Preview AvailableA multicentre point prevalence study of delirium assessment and management in patients admitted to Australian and New Zealand intensive care units(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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ItemReplication: Belief elicitation with quadratic and binarized scoring rules(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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ItemProlonged Eyelid Closure Episodes during Sleep Deprivation in Professional Drivers(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.
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ItemNo Preview AvailableIncidence and seroprevalence of dengue virus infections in Australian travellers to Asia(SPRINGER, 2012-06)The purpose of this study was to estimate the incidence density and prevalence of dengue virus infection in Australian travellers to Asia. We conducted a multi-centre prospective cohort study of Australian travellers over a 32-month period. We recruited 467 travellers (≥ 16 years of age) from three travel clinics who intended to travel Asia, and 387 (82.9%) of those travellers completed questionnaires and provide samples pre- and post-travel for serological testing for dengue virus infection. Demographic data, destination countries and history of vaccinations and flavivirus infections were obtained. Serological testing for dengue IgG and IgM by enzyme-linked immunosorbent assay (ELISA) (PanBio assay) was performed. Acute seroconversion for dengue infection was demonstrated in 1.0% of travellers, representing an incidence of 3.4 infections per 10,000 days of travel (95% confidence interval [CI]: 0.9-8.7). The seroprevalence of dengue infection was 4.4% and a greater number of prior trips to Asia was a predictor for dengue seroprevalence (p = 0.019). All travellers experienced subclinical dengue infections and had travelled to India (n = 3) and China (n = 1). This significant attack rate of dengue infection can be used to advise prospective travellers to dengue-endemic countries.
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ItemNo Preview AvailablePrevalence and risk factors for symptoms of common mental disorders in early and late pregnancy in Vietnamese women: A prospective population-based study(Elsevier, 2013-04-05)BACKGROUND: Little is known about the prevalence of and risk factors for common mental disorders (CMD) in pregnant women in low-income countries. The aim of this study was to establish the prevalence of and psychosocial risk factors for clinically significant symptoms of CMD in early and late pregnancy in women in rural Viet Nam. METHODS: A population-based sample of women was surveyed in early and late pregnancy. CMD were assessed by the Edinburgh Postnatal Depression Scale-Viet Nam Validation and psychosocial risks by study-specific structured interviews. RESULTS: In total 497/523 (97%) eligible women were recruited and 419 (84%) provided complete data. Prevalence of CMD only in early pregnancy was 22.4% (95% CI 18.4-26.4); only in late pregnancy was 10.7% (95% CI 7.8-13.7) and at both assessment waves was 17.4% (95% CI 13.8-21.1). Non-economic and economic coincidental life adversity, intimate partner violence, past pregnancy loss, and childhood abuse were positively associated with persistent antenatal CMD. Older age, having a preference for the baby's sex, and nulli- or primiparity were risk factors for CMD in early pregnancy. CONCLUSIONS: Persistent antenatal CMD are prevalent in rural areas of Viet Nam. Psychosocial risk factors play a major role in this significant public health problem.
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ItemNo Preview AvailableIntimate partner violence and perinatal common mental disorders among women in rural Vietnam(Oxford University Press, 2013-03-01)INTRODUCTION: Intimate partner violence against women (IPV) is regarded increasingly as a public health problem worldwide. The overall aim of this study was to examine the associations between different exposures to IPV and women's mental health during pregnancy and after childbirth in rural Vietnam. METHODS: This was a secondary analysis of data generated in a community-based longitudinal investigation in which a cohort of pregnant women were recruited and followed until 6 months after childbirth. Different forms of IPV were measured by the Intimate Partner Violence section of the WHO Multi-Country Study on Women's Health and Domestic Violence Against Women questionnaire. The Edinburgh Postnatal Depression Scale-Vietnam Validation was used to assess symptoms of the common perinatal mental disorders of depression and anxiety (CPMD). RESULTS: Overall, 497 women were recruited and complete data were available from 417 (83.9%). Exposure to either lifetime or perinatal IPV including emotional abuse, physical violence and sexual violence was associated with increased CPMD symptoms (adjusted odds ratio, OR, ranges 1.3-14.3) and suicidal thoughts (OR ranges 4.7-6.1) in women during pregnancy and after childbirth. Experiencing more than one form of IPV increased the magnitude of the association between IPV and CPMD symptoms and thoughts of suicide. CONCLUSION: It is clearly essential in this and other resource-constrained settings to address emotional, physical and sexual violence perpetrated by an intimate partner in any strategies to reduce the risk of perinatal mental health problems in women.
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ItemValidation of the Intimate Bonds Measure for women who are pregnant or have recently given birth in Vietnam(WILEY, 2014-03)INTRODUCTION: Sensitive, valid measures to assess the quality of the intimate partner relationship are necessary for both clinical practice and research. The aim of this study was to examine the validity of the Intimate Bonds Measure (IBM) in women who were pregnant or had recently given birth in Vietnam. METHODS: The IBM was translated and culturally verified in a step-by-step process with Vietnamese health workers, researchers and community members. The validation study was nested within two larger community-based cross-sectional investigations: the first in 2006, which recruited 199 pregnant women and 165 mothers of newborns, and the second in 2010, which recruited 419 pregnant women. Internal structure was assessed by factor analysis and Cronbach's alpha and construct validity by comparison with relevant factors. RESULTS: Exploratory factor analyses revealed an identical factor structure to the one reported by the measure's developers in an Anglophone Australian population more than 20 years ago. The two factors replicate exactly the Care and Control subscales and Cronbach's alpha (from 0.68 to 0.83) indicates high internal consistency in both sub-scales. Mean scores of the Care-V and Control-V sub-scales were associated significantly and in expected directions with whether a woman could confide in, felt supported by or was frightened of her partner, or had experienced intimate partner violence and measures of mental health status. DISCUSSION: The Vietnamese version of the IBM (IBM-V) is comprehensible, meaningful and appears to be a valid measure the construct of quality of relationship with an intimate partner among women in this setting.
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ItemIncorporation of Vanadium and Molybdenum into Yttrium-Arsenotungstates Supported by Amino Acid Ligands(CSIRO PUBLISHING, 2020)The preference for incorporation of molybdenum over tungsten into specific sites of a family of yttrium-arsenotungstates with amino acid ligands prompted exploration of the incorporation of other metals, affording three new vanadium-containing (V/W and V/Mo/W) analogues: K2(GlyH)10[As4(V2W2)W44Y4O160(Gly)8(H2O)12]·11Gly (1), (MBAH)9(L-NleH)3[As4(V2W2)W44Y4O160(L-Nle)8(H2O)12] (2), and (MBAH)9(L-NleH)3[As4(V2W2)Mo2W42Y4O160(L-Nle)8(H2O)12] (3) (Gly=glycine and L-Nle=l-norleucine, MBAH=4-methylbenzylammonium). These hybrid polyoxometalates all possess a tetrametallic oxo-bridged {VIV2WVI2} central core surrounded by an amino acid-ligated cyclic metal-oxo framework. X-Ray photoelectron, UV-visible reflectance, and electron paramagnetic resonance spectroscopy, together with metal analysis, confirm the incorporation of vanadium into the polyoxometalates, while single crystal X-ray diffraction analysis supports the location of the vanadium atoms in the central core.
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ItemMetabolomes and Lipidomes of the Infective Stages of the Gastrointestinal nematodes, Nippostrongylus brasiliensis and Trichuris muris(MDPI, 2020-11)Soil-transmitted helminths, including hookworms and whipworms, infect billions of people worldwide. Their capacity to penetrate and migrate through their hosts' tissues is influenced by the suite of molecules produced by the infective developmental stages. To facilitate a better understanding of the immunobiology and pathogenicity of human hookworms and whipworms, we investigated the metabolomes of the infective stage of Nippostrongylus brasiliensis third-stage larvae (L3) which penetrate the skin and Trichuris muris eggs which are orally ingested, using untargeted liquid chromatography-mass spectrometry (LC-MS). We identified 55 polar metabolites through Metabolomics Standard Initiative level-1 (MSI-I) identification from N. brasiliensis and T. muris infective stages, out of which seven were unique to excretory/secretory products (ESPs) of N. brasiliensis L3. Amino acids were a principal constituent (33 amino acids). Additionally, we identified 350 putative lipids, out of which 28 (all known lipids) were unique to N. brasiliensis L3 somatic extract and four to T. muris embryonated egg somatic extract. Glycerophospholipids and glycerolipids were the major lipid groups. The catalogue of metabolites identified in this study shed light on the biology, and possible therapeutic and diagnostic targets for the treatment of these critical infectious pathogens. Moreover, with the growing body of literature on the therapeutic utility of helminth ESPs for treating inflammatory diseases, a role for metabolites is likely but has received little attention thus far.