24 results on '"D’Arcy, P."'
Search Results
2. Risk of suicide ideation in comorbid substance use disorder and major depression.
- Author
-
Vivian N Onaemo, Timothy O Fawehinmi, and Carl D'Arcy
- Subjects
Medicine ,Science - Abstract
BackgroundSuicidal behaviour is commonly associated with major depression (MD) and substance use disorders (SUDs). However, there is a paucity of research on risk for suicide ideation among individuals with comorbid SUDs and MD in the general population.ObjectivesThis study investigated the associated risk of suicide ideation in comorbid SUDs-cannabis use disorder (CUD), alcohol use disorder (AUD), drug use disorder (DUD) with major depressive episode (MDE) in a nationally representative sample.MethodsMultilevel logistic regression models were used to analyze the 2012 Canadian Community Health Survey- Mental Health (CCHS-MH) data. This is a cross-sectional survey of nationally representative samples of Canadians (n = 25,113) aged 15 years and older residing in the ten Canadian provinces between January and December 2012. Diagnoses of MDE, AUD, DUD, and CUD were based on a modified WHO-CIDI, derived from DSM-IV diagnostic criteria.ResultsComorbidity was found to be the strongest predictor of suicide ideation. Compared to those with no diagnosis of either a SUD or MDE, individuals with a comorbid diagnosis of AUD with MDE, CUD with MDE, or DUD with MDE were 9, 11 and 16 times more likely to have 12-month suicide ideation respectively. A diagnosis of MDE was a significant predictor of 12-month suicide ideation with about a 7-fold increased risk compared with individuals not diagnosed with either MDE or a SUD.ConclusionSuicide is a preventable public health issue. Our study found a significantly increased risk of suicide ideation among persons who have comorbid SUD with MD. Effective integration of mental health and addictions services could mitigate the risk of suicide and contribute to better outcomes.
- Published
- 2022
- Full Text
- View/download PDF
3. The IL-4/IL-13 signaling axis promotes prostatic fibrosis
- Author
-
Quentin D’Arcy, Mehrnaz Gharaee-Kermani, Alisa Zhilin-Roth, and Jill A. Macoska
- Subjects
Medicine ,Science - Abstract
Background Lower urinary tract symptoms (LUTS) are a costly and pervasive medical problem for millions of aging men. Recent studies have showed that peri-urethral tissue fibrosis is an untreated pathobiology contributing to LUTS. Fibrosis results from excessive extracellular matrix deposition which increases transition zone and peri-urethral tissue stiffness and compromises prostatic urethral flexibility and compliance, producing urinary obstructive symptoms. Inflammatory cells, including neutrophils, macrophages, and T-lymphocytes, secrete a medley of pro-fibrotic proteins into the prostatic microenvironment, including IFNγ, TNFα, CXC-type chemokines, and interleukins, all of which have been implicated in inflammation-mediated fibrosis. Among these, IL-4 and IL-13 are of particular interest because they share a common signaling axis that, as shown here for the first time, promotes the expression and maintenance of IL-4, IL-13, their cognate receptors, and ECM components by prostate fibroblasts, even in the absence of immune cells. Based on studies presented here, we hypothesize that the IL-4/IL-13 axis promotes prostate fibroblast activation to ECM-secreting cells. Methods N1 or SFT1 immortalized prostate stromal fibroblasts were cultured and treated, short- or long-term, with pro-fibrotic proteins including IL-4, IL-13, TGF-β, TNF-α, IFNγ, with or without prior pre-treatment with antagonists or inhibitors. Protein expression was assessed by immunohistochemistry, immunofluorescence, ELISA, immunoblot, or Sircoll assays. Transcript expression levels were determined by qRT-PCR. Intact cells were counted using WST assays. Results IL-4Rα, IL-13Rα1, and collagen are concurrently up-regulated in human peri-urethral prostate tissues from men with LUTS. IL-4 and IL-13 induce their own expression as well as that of their cognate receptors, IL-4Rα and IL-13Rα1. Low concentrations of IL-4 or IL-13 act as cytokines to promote prostate fibroblast proliferation, but higher (>40ng/ml) concentrations repress cellular proliferation. Both IL-4 and IL-13 robustly and specifically promote collagen transcript and protein expression by prostate stromal fibroblasts in a JAK/STAT-dependent manner. Moreover, IL-4 and IL-13-mediated JAK/STAT signaling is coupled to activation of the IL-4Rα receptor. Conclusions Taken together, these studies show that IL-4 and IL-13 signal through the IL-4Rα receptor to activate JAK/STAT signaling, thereby promoting their own expression, that of their cognate receptors, and collagens. These finding suggest that the IL-4/IL-13 signaling axis is a powerful, but therapeutically targetable, pro-fibrotic mechanism in the lower urinary tract.
- Published
- 2022
4. A comparison of the prevalence of and modifiable risk factors for cognitive impairment among community-dwelling Canadian seniors over two decades, 1991-2009.
- Author
-
Batholomew Chireh and Carl D'Arcy
- Subjects
Medicine ,Science - Abstract
BackgroundThe prevalence of cognitive impairment or dementia is of public health concern globally. Accurate estimates of this debilitating condition are needed for future public health policy planning. In this study, we estimate prevalence and modifiable risk factors for cognitive impairment by sex over approximately 16 years.MethodsCanadian Study of Health and Aging (CSHA) baseline data conducted between 1991-1992 were used to measure the prevalence of cognitive impairment and dementia among adults aged 65+ years. The standard Modified Mini-Mental State Examination (3MS) was used for the screening test for cognitive impairment. We compared the CSHA data with Canadian Community Health Survey-Healthy Aging (CCHS-HA) conducted between 2008-2009. The CCHS-HA used a four-dimension cognitive module to screen for cognitive impairment. Only survey community-dwelling respondents were included in the final sample. After applying exclusion criteria, final samples of (N = 8504) respondents in the CSHA sample and (N = 7764) respondents for CCHS-HA sample were analyzed. To account for changes in the age structure of the Canadian population, prevalence estimates were calculated using age-sex standardization to the 2001 population census of Canada. Logistic regression analyses were used to examine predictors of cognitive impairment. A sex stratified analysis was used to examine risk factors for cognitive impairment in the survey samples.ResultsWe found that prevalence of cognitive impairment among respondents in CSHA sample was 15.5% in 1991 while a prevalence of 10.8% was reported in the CCHS-HA sample in 2009, a 4.7% reduction [15.5% (CI = 14.8-16.3), CSHA vs 10.8% (CI = 10.1-11.5), CCHS-HA]. Men reported higher prevalence of cognitive impairment in CSHA study (16.0%) while women reported higher prevalence of cognitive impairment in CCHS-HA (11.6%). In the multivariable analyses, risk factors such as age, poor self-rated health, stroke, Parkinson's disease, and hearing problems were common to both cohorts. Sex differences in risk factors were also noted.ConclusionsThis study provides suggestive evidence of a potential reduction in the occurrence of cognitive impairment among community-dwelling Canadian seniors despite the aging of the Canadian population. The moderating roles of improved prevention and treatment of vascular morbidity and improvements in the levels of education of the Canadian population are possible explanations for this decrease in the cognitive impairment.
- Published
- 2020
- Full Text
- View/download PDF
5. Reproducible big data science: A case study in continuous FAIRness.
- Author
-
Ravi Madduri, Kyle Chard, Mike D'Arcy, Segun C Jung, Alexis Rodriguez, Dinanath Sulakhe, Eric Deutsch, Cory Funk, Ben Heavner, Matthew Richards, Paul Shannon, Gustavo Glusman, Nathan Price, Carl Kesselman, and Ian Foster
- Subjects
Medicine ,Science - Abstract
Big biomedical data create exciting opportunities for discovery, but make it difficult to capture analyses and outputs in forms that are findable, accessible, interoperable, and reusable (FAIR). In response, we describe tools that make it easy to capture, and assign identifiers to, data and code throughout the data lifecycle. We illustrate the use of these tools via a case study involving a multi-step analysis that creates an atlas of putative transcription factor binding sites from terabytes of ENCODE DNase I hypersensitive sites sequencing data. We show how the tools automate routine but complex tasks, capture analysis algorithms in understandable and reusable forms, and harness fast networks and powerful cloud computers to process data rapidly, all without sacrificing usability or reproducibility-thus ensuring that big data are not hard-to-(re)use data. We evaluate our approach via a user study, and show that 91% of participants were able to replicate a complex analysis involving considerable data volumes.
- Published
- 2019
- Full Text
- View/download PDF
6. Analysis of determinants for in vitro resistance to the small molecule deubiquitinase inhibitor b-AP15.
- Author
-
Arjan Mofers, Paola Perego, Karthik Selvaraju, Laura Gatti, Joachim Gullbo, Stig Linder, and Padraig D'Arcy
- Subjects
Medicine ,Science - Abstract
BACKGROUND:b-AP15/VLX1570 are small molecule inhibitors of the ubiquitin specific peptidase 14 (USP14) and ubiquitin carboxyl-terminal hydrolase 5 (UCHL5) deubiquitinases (DUBs) of the 19S proteasome. b-AP15/VLX1570 have been shown to be cytotoxic to cells resistant to bortezomib, raising the possibility that this class of drugs can be used as a second-line therapy for treatment-resistant multiple myeloma. Limited information is available with regard to potential resistance mechanisms to b-AP15/VLX1570. RESULTS:We found that b-AP15-induced cell death is cell-cycle dependent and that non-cycling tumor cells may evade b-AP15-induced cell death. Such non-cycling cells may re-enter the proliferative state to form colonies of drug-sensitive cells. Long-term selection of cells with b-AP15 resulted in limited drug resistance (~2-fold) that could be reversed by buthionine sulphoximine, implying altered glutathione (GSH) metabolism as a resistance mechanism. In contrast, drug uptake and overexpression of drug efflux transporters were found not to be associated with b-AP15 resistance. CONCLUSIONS:The proteasome DUB inhibitors b-AP15/VLX1570 are cell cycle-active. The slow and incomplete development of resistance towards these compounds is an attractive feature in view of future clinical use.
- Published
- 2019
- Full Text
- View/download PDF
7. FHL1 reduces dystrophy in transgenic mice overexpressing FSHD muscular dystrophy region gene 1 (FRG1).
- Author
-
Sandra J Feeney, Meagan J McGrath, Absorn Sriratana, Stefan M Gehrig, Gordon S Lynch, Colleen E D'Arcy, John T Price, Catriona A McLean, Rossella Tupler, and Christina A Mitchell
- Subjects
Medicine ,Science - Abstract
Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal-dominant disease with no effective treatment. The genetic cause of FSHD is complex and the primary pathogenic insult underlying the muscle disease is unknown. Several disease candidate genes have been proposed including DUX4 and FRG1. Expression analysis studies of FSHD report the deregulation of genes which mediate myoblast differentiation and fusion. Transgenic mice overexpressing FRG1 recapitulate the FSHD muscular dystrophy phenotype. Our current study selectively examines how increased expression of FRG1 may contribute to myoblast differentiation defects. We generated stable C2C12 cell lines overexpressing FRG1, which exhibited a myoblast fusion defect upon differentiation. To determine if myoblast fusion defects contribute to the FRG1 mouse dystrophic phenotype, this strain was crossed with skeletal muscle specific FHL1-transgenic mice. We previously reported that FHL1 promotes myoblast fusion in vitro and FHL1-transgenic mice develop skeletal muscle hypertrophy. In the current study, FRG1 mice overexpressing FHL1 showed an improvement in the dystrophic phenotype, including a reduced spinal kyphosis, increased muscle mass and myofiber size, and decreased muscle fibrosis. FHL1 expression in FRG1 mice, did not alter satellite cell number or activation, but enhanced myoblast fusion. Primary myoblasts isolated from FRG1 mice showed a myoblast fusion defect that was rescued by FHL1 expression. Therefore, increased FRG1 expression may contribute to a muscular dystrophy phenotype resembling FSHD by impairing myoblast fusion, a defect that can be rescued by enhanced myoblast fusion via expression of FHL1.
- Published
- 2015
- Full Text
- View/download PDF
8. Hospital mental health admissions in women after unsuccessful infertility treatment and in vitro fertilization: an Australian population-based cohort study.
- Author
-
Louise M Stewart, C D'Arcy J Holman, James B Semmens, David Preen, Qun Mai, and Roger Hart
- Subjects
Medicine ,Science - Abstract
To examine the association between in vitro fertilization (IVF) and later admission to hospital with a mental health diagnosis in women who remained childless after infertility treatment.This was a population-based cohort study using linked administrative hospital and registry data. The study population included all women commencing hospital treatment for infertility in Western Australia between the years 1982 and 2002 aged 20-44 years at treatment commencement who did not have a recorded birth by the end of follow-up (15 August 2010) and did not have a hospital mental health admission prior to the first infertility admission (n=6,567). Of these, 2,623 women had IVF and 3,944 did not. We used multivariate Cox regression modeling of mental health admissions and compared women undergoing IVF treatment with women having infertility treatment but not IVF.Over an average of 17 years of follow-up, 411 women in the cohort were admitted to hospital with a mental health diagnosis; 93 who had IVF and 318 who did not. The unadjusted hazard ratio (HR) for a hospital mental health admission comparing women who had IVF with those receiving other infertility treatment was 0.50 (95% confidence interval [CI] 0.40-0.63). After adjustment for age, calendar year and socio-economic status the HR was 0.56 (95% CI 0.44-0.71).IVF treatment is associated with a reduced risk of hospital mental health admissions in women after unsuccessful infertility treatment. This may be explained by the healthy cohort effect.
- Published
- 2015
- Full Text
- View/download PDF
9. A method to assess adherence in inhaler use through analysis of acoustic recordings of inhaler events.
- Author
-
Shona D'Arcy, Elaine MacHale, Jansen Seheult, Martin S Holmes, Cian Hughes, Imran Sulaiman, Deirdre Hyland, Conor O'Reilly, Senan Glynn, Thekra Al-Zaabi, John McCourt, Terence Taylor, Frank Keane, Isabelle Killane, Richard B Reilly, and Richard W Costello
- Subjects
Medicine ,Science - Abstract
RationalePoor adherence to inhaler use can be due to poor temporal and/or technique adherence. Up until now there has been no way of reliably tracking both these factors in everyday inhaler use.ObjectivesThis paper introduces a device developed to create time stamped acoustic recordings of an individual's inhaler use, in which empirical evidence of temporal and technique adherence in inhaler use can be monitored over time. The correlation between clinical outcomes and adherence, as determined by this device, was compared for temporal adherence alone and combined temporal and technique adherence.FindingsThe technology was validated by showing that the doses taken matched the number of audio recordings (r2 = 0.94, p20% of their inhaler events. Repeated training reduced this to 7% of participants (p = 0.03). When time of use was considered, there was no evidence of a relationship between adherence and changes in AQLQ (r2 = 0.2) or PEFR (r2 = 0.2). Combining time and technique the rate of adherence was related to changes in AQLQ (r2 = 0.53, p = 0.01) and PEFR (r2 = 0.29, p = 0.01).ConclusionsThis study presents a novel method to objectively assess how errors in both time and technique of inhaler use impact on clinical outcomes.Trial registrationEudraCT 2011-004149-42.
- Published
- 2014
- Full Text
- View/download PDF
10. Elevation of proteasomal substrate levels sensitizes cells to apoptosis induced by inhibition of proteasomal deubiquitinases.
- Author
-
Chao Sun, Peristera Roboti, Marjo-Riitta Puumalainen, Mårten Fryknäs, Xin Wang, Padraig D'Arcy, Malin Hult, Stephen High, Stig Linder, and Eileithyia Swanton
- Subjects
Medicine ,Science - Abstract
Inhibitors of the catalytic activity of the 20S proteasome are cytotoxic to tumor cells and are currently in clinical use for treatment of multiple myeloma, whilst the deubiquitinase activity associated with the 19S regulatory subunit of the proteasome is also a valid target for anti-cancer drugs. The mechanisms underlying the therapeutic efficacy of these drugs and their selective toxicity towards cancer cells are not known. Here, we show that increasing the cellular levels of proteasome substrates using an inhibitor of Sec61-mediated protein translocation significantly increases the extent of apoptosis that is induced by inhibition of proteasomal deubiquitinase activity in both cancer derived and non-transformed cell lines. Our results suggest that increased generation of misfolded proteasome substrates may contribute to the mechanism(s) underlying the increased sensitivity of tumor cells to inhibitors of the ubiquitin-proteasome system.
- Published
- 2014
- Full Text
- View/download PDF
11. Oncogenic functions of the cancer-testis antigen SSX on the proliferation, survival, and signaling pathways of cancer cells.
- Author
-
Padraig D'Arcy, Wessen Maruwge, Barry Wolahan, Limin Ma, and Bertha Brodin
- Subjects
Medicine ,Science - Abstract
SSX is a transcription factor with elusive oncogenic functions expressed in a variety of human tumors of epithelial and mesenchymal origin. It has raised substantial interest as a target for cancer therapy since it elicits humoral responses and displays restricted expression to cancer, spermatogonia and mesenchymal stem cells. Here, we investigated the oncogenic properties of SSX by employing a RNA interference to knock-down the endogenous expression of SSX in melanoma and osteosarcoma cell lines. Depletion of SSX expression resulted in reduced proliferation with cells accumulating in the G1 phase of the cell cycle. We found that the growth promoting and survival properties of SSX are mediated in part though modulation of MAPK/Erk and Wnt signaling pathways, since SSX silencing inhibited Erk-mediated signaling and transcription of cMYC and Akt-1. We also found that SSX forms a transient complex with β-catenin at the G1-S phase boundary resulting in the altered expression of β-catenin target genes such as E-cadherin, snail-2 and vimentin, involved in epithelial-mesenchymal transitions. Importantly the silencing of SSX expression in in vivo significantly impaired the growth of melanoma tumor xenografts. Tumor biopsies from SSX silenced tumors displayed reduced cyclin A staining, indicative of low proliferation and predominantly cycloplasmic β-catenin compared to SSX expressing tumors. The present study demonstrates a previously unknown function of SSX, that as an oncogene and as a tumor target for the development of novel anti-cancer drugs.
- Published
- 2014
- Full Text
- View/download PDF
12. The MyD88+ phenotype is an adverse prognostic factor in epithelial ovarian cancer.
- Author
-
Charles J d'Adhemar, Cathy D Spillane, Michael F Gallagher, Mark Bates, Katie M Costello, Jacqui Barry-O'Crowley, Kathryn Haley, Niamh Kernan, Ciara Murphy, Paul C Smyth, Ken O'Byrne, Stephen Pennington, Aoife A Cooke, Brendan Ffrench, Cara M Martin, Dearbhaile O'Donnell, Bryan Hennessy, Britta Stordal, Stephen Finn, Amanda McCann, Noreen Gleeson, Tom D'Arcy, Brian Flood, Luke A J O'Neill, Orla Sheils, Sharon O'Toole, and John J O'Leary
- Subjects
Medicine ,Science - Abstract
The prognosis of epithelial ovarian cancer is poor in part due to the high frequency of chemoresistance. Recent evidence points to the Toll-like receptor-4 (TLR4), and particularly its adaptor protein MyD88, as one potential mediator of this resistance. This study aims to provide further evidence that MyD88 positive cancer cells are clinically significant, stem-like and reproducibly detectable for the purposes of prognostic stratification. Expression of TLR4 and MyD88 was assessed immunohistochemically in 198 paraffin-embedded ovarian tissues and in an embryonal carcinoma model of cancer stemness. In parallel, expression of TLR4 and MyD88 mRNA and regulatory microRNAs (miR-21 and miR-146a) was assessed, as well as in a series of chemosensitive and resistant cancer cells lines. Functional analysis of the pathway was assessed in chemoresistant SKOV-3 ovarian cancer cells. TLR4 and MyD88 expression can be reproducibly assessed via immunohistochemistry using a semi-quantitative scoring system. TLR4 expression was present in all ovarian epithelium (normal and neoplastic), whereas MyD88 was restricted to neoplastic cells, independent of tumour grade and associated with reduced progression-free and overall survival, in an immunohistological specific subset of serous carcinomas, p
- Published
- 2014
- Full Text
- View/download PDF
13. Adverse obstetric and perinatal outcomes following treatment of adolescent and young adult cancer: a population-based cohort study.
- Author
-
Fatima A Haggar, Gavin Pereira, David Preen, C D'Arcy Holman, and Kristjana Einarsdottir
- Subjects
Medicine ,Science - Abstract
To investigate obstetric and perinatal outcomes among female survivors of adolescent and young adult (AYA) cancers and their offspring.Using multivariate analysis of statewide linked data, outcomes of all first completed pregnancies (n = 1894) in female survivors of AYA cancer diagnosed in Western Australia during the period 1982-2007 were compared with those among females with no cancer history. Comparison pregnancies were matched by maternal age-group, parity and year of delivery.Compared with the non-cancer group, female survivors of AYA cancer had an increased risk of threatened abortion (adjusted relative risk 2.09, 95% confidence interval 1.51-2.74), gestational diabetes (2.65, 2.08-3.57), pre-eclampsia (1.32, 1.04-1.87), post-partum hemorrhage (2.83, 1.92-4.67), cesarean delivery (2.62, 2.22-3.04), and maternal postpartum hospitalization>5 days (3.01, 1.72-5.58), but no excess risk of threatened preterm delivery, antepartum hemorrhage, premature rupture of membranes, failure of labor to progress or retained placenta. Their offspring had an increased risk of premature birth (
- Published
- 2014
- Full Text
- View/download PDF
14. Peri-transplant psychosocial factors and neutrophil recovery following hematopoietic stem cell transplantation.
- Author
-
Jennifer M Knight, Jan A Moynihan, Jeffrey M Lyness, Yinglin Xia, Xin Tu, Susan Messing, Bryan C Hunter, Li-Shan Huang, Rosemary O Obi, D'Arcy Gaisser, Jane L Liesveld, and Olle Jane Z Sahler
- Subjects
Medicine ,Science - Abstract
Multiple psychosocial factors appear to affect cancer progression in various populations; however, research investigating the relationship between psychosocial factors and outcomes following hematopoietic stem cell transplantation (HCT) is scarce. Subject to adverse immunological and psychological conditions, HCT patients may be especially vulnerable to psychosomatic health sequelae; therefore, we studied whether optimism and anxiety influence the pertinent clinical outcome of days to neutrophil engraftment (DTE).54 adults undergoing either autologous or allogeneic HCT completed self-report questionnaires measuring optimism and anxiety. We assessed the association between these psychosocial variables and DTE.Greater optimism and less anxiety were associated with the favorable outcome of fewer DTE in autologous HCT recipients, though this relationship was no longer significant when reducing the sample size to only subjects who filled out their baseline survey by the time of engraftment.Our findings are suggestive that optimism and anxiety may be associated with time to neutrophil recovery in autologous, but not allogeneic, adult HCT recipients. Further investigation in larger, more homogeneous subjects with consistent baseline sampling is warranted.
- Published
- 2014
- Full Text
- View/download PDF
15. Women commencing anastrozole, letrozole or tamoxifen for early breast cancer: the impact of comorbidity and demographics on initial choice.
- Author
-
Anna Kemp, David B Preen, Christobel Saunders, Frances Boyle, Max Bulsara, C D'Arcy J Holman, Eva Malacova, and Elizabeth E Roughead
- Subjects
Medicine ,Science - Abstract
Australian clinical guidelines recommend endocrine therapy for all women with hormone-dependent early breast cancer. Guidelines specify tamoxifen as first-line therapy for pre-menopausal women, and tamoxifen or an aromatase inhibitor (AI) for post-menopausal women depending on the risk of recurrence based on tumour characteristics including size. Therapies have different side effect profiles; therefore comorbidity may also influence choice. We examined comorbidity, and the clinical and demographic characteristics of women commencing different therapies.We identified the first dispensing of tamoxifen, anastrozole or letrozole for women diagnosed with invasive breast cancer in the 45 and Up Study from 2004-2009 (N = 1266). Unit-level pharmacy and medical service claims, hospital, Cancer Registry, and self-reported data were linked to determine menopause status at diagnosis, tumour size, age, comorbidities, and change in subsidy restrictions. Chi-square tests and generalised regression models were used to compare the characteristics of women commencing different therapies.Most pre-menopausal women commenced therapy with tamoxifen (91%). Anastrozole was the predominant therapy for post-menopausal women (57%), followed by tamoxifen (28%). Women with osteoporosis were less likely to commence anastrozole compared with tamoxifen (anastrozole RR = 0.7, 95% CI = 0.5-0.9). Women with arthritis were 1.6-times more likely to commence letrozole than anastrozole (95% CI = 1.1-2.1). Tamoxifen was more often initiated in women with tumours >1 cm, who were also ≥75 years. Subsidy restriction changes were associated with substantial increases in the proportion of women commencing AIs (anastrozole RR = 4.3, letrozole RR = 8.3).The findings indicate interplay of comorbidity and therapy choice for women with invasive breast cancer. Most post-menopausal women commenced therapy with anastrozole; however, letrozole and tamoxifen were more often initiated for women with comorbid arthritis and osteoporosis, respectively. Tamoxifen was also more common for women with tumours >1 cm and aged ≥75 years. Subsidy restrictions appear to have strongly influenced therapy choice.
- Published
- 2014
- Full Text
- View/download PDF
16. Sensitivity to white matter FMRI activation increases with field strength.
- Author
-
Erin L Mazerolle, Jodie R Gawryluk, Kim N H Dillen, Steven A Patterson, Kirk W Feindel, Steven D Beyea, M Tynan R Stevens, Aaron J Newman, Matthias H Schmidt, and Ryan C N D'Arcy
- Subjects
Medicine ,Science - Abstract
Functional magnetic resonance imaging (fMRI) activation in white matter is controversial. Given that many of the studies that report fMRI activation in white matter used high field MRI systems, we investigated the field strength dependence of sensitivity to white matter fMRI activation. In addition, we evaluated the temporal signal to noise ratio (tSNR) of the different tissue types as a function of field strength. Data were acquired during a motor task (finger tapping) at 1.5 T and 4 T. Group and individual level activation results were considered in both the sensorimotor cortex and the posterior limb of the internal capsule. We found that sensitivity increases associated with field strength were greater for white matter than gray matter. The analysis of tSNR suggested that white matter might be less susceptible to increases in physiological noise related to increased field strength. We therefore conclude that high field MRI may be particularly advantageous for fMRI studies aimed at investigating activation in both gray and white matter.
- Published
- 2013
- Full Text
- View/download PDF
17. Cancer survival and excess mortality estimates among adolescents and young adults in Western Australia, 1982-2004: a population-based study.
- Author
-
Fatima A Haggar, Gavin Pereira, David D Preen, C D'Arcy J Holman, and Kristjana Einarsdottir
- Subjects
Medicine ,Science - Abstract
Data are limited on cancer outcomes in adolescents and young adults.Based on data from the Western Australian Data Linkage System, this study modelled survival and excess mortality in all adolescents and young adults aged 15-39 years in Western Australia who had a diagnosis of cancer in the period 1982-2004. Relative survival and excess all-cause mortality for all cancers combined and for principal tumour subgroups were estimated, using the Ederer II method and generalised linear Poisson modelling, respectively.A cancer diagnosis in adolescents and young adults conferred substantial survival decrement. However, overall outcomes improved over calendar period (excess mortality hazard ratio [HR], latest versus earliest diagnostic period: 0.52, trend p
- Published
- 2013
- Full Text
- View/download PDF
18. Healthcare environments and spatial variability of healthcare associated infection risk: cross-sectional surveys.
- Author
-
Jean Gaudart, Elaine Cloutman-Green, Serge Guillas, Nikki D'Arcy, John C Hartley, Vanya Gant, and Nigel Klein
- Subjects
Medicine ,Science - Abstract
Prevalence of healthcare associated infections remains high in patients in intensive care units (ICU), estimated at 23.4% in 2011. It is important to reduce the overall risk while minimizing the cost and disruption to service provision by targeted infection control interventions. The aim of this study was to develop a monitoring tool to analyze the spatial variability of bacteriological contamination within the healthcare environment to assist in the planning of interventions. Within three cross-sectional surveys, in two ICU wards, air and surface samples from different heights and locations were analyzed. Surface sampling was carried out with tryptic Soy Agar contact plates and Total Viable Counts (TVC) were calculated at 48 hrs (incubation at 37 °C). TVCs were analyzed using Poisson Generalized Additive Mixed Model for surface type analysis, and for spatial analysis. Through three cross-sectional survey, 370 samples were collected. Contamination varied from place-to-place, height-to-height, and by surface type. Hard-to-reach surfaces, such as bed wheels and floor area under beds, were generally more contaminated, but the height level at which maximal TVCs were found changed between cross-sectional surveys. Bedside locations and bed occupation were risk factors for contamination. Air sampling identified clusters of contamination around the nursing station and surface sampling identified contamination clusters at numerous bed locations. By investigating dynamic hospital wards, the methodology employed in this study will be useful to monitor contamination variability within the healthcare environment and should help to assist in the planning of interventions.
- Published
- 2013
- Full Text
- View/download PDF
19. Increase in caesarean deliveries after the Australian Private Health Insurance Incentive policy reforms.
- Author
-
Kristjana Einarsdóttir, Anna Kemp, Fatima A Haggar, Rachael E Moorin, Anthony S Gunnell, David B Preen, Fiona J Stanley, and C D'Arcy J Holman
- Subjects
Medicine ,Science - Abstract
BackgroundThe Australian Private Health Insurance Incentive (PHII) policy reforms implemented in 1997-2000 increased PHI membership in Australia by 50%. Given the higher rate of obstetric interventions in privately insured patients, the reforms may have led to an increase in surgical deliveries and deliveries with longer hospital stays. We aimed to investigate the effect of the PHII policy introduction on birth characteristics in Western Australia (WA).Methods and findingsAll 230,276 birth admissions from January 1995 to March 2004 were identified from administrative birth and hospital data-systems held by the WA Department of Health. Average quarterly birth rates after the PHII introduction were estimated and compared with expected rates had the reforms not occurred. Rate and percentage differences (including 95% confidence intervals) were estimated separately for public and private patients, by mode of delivery, and by length of stay in hospital following birth. The PHII policy introduction was associated with a 20% (-21.4 to -19.3) decrease in public birth rates, a 51% (45.1 to 56.4) increase in private birth rates, a 5% (-5.3 to -5.1) and 8% (-8.9 to -7.9) decrease in unassisted and assisted vaginal deliveries respectively, a 5% (-5.3 to -5.1) increase in caesarean sections with labour and 10% (8.0 to 11.7) increase in caesarean sections without labour. Similarly, birth rates where the infant stayed 0-3 days in hospital following birth decreased by 20% (-21.5 to -18.5), but rates of births with >3 days in hospital increased by 15% (12.2 to 17.1).ConclusionsFollowing the PHII policy implementation in Australia, births in privately insured patients, caesarean deliveries and births with longer infant hospital stays increased. The reforms may not have been beneficial for quality obstetric care in Australia or the burden of Australian hospitals.
- Published
- 2012
- Full Text
- View/download PDF
20. Education and dementia in the context of the cognitive reserve hypothesis: a systematic review with meta-analyses and qualitative analyses.
- Author
-
Xiangfei Meng and Carl D'Arcy
- Subjects
Medicine ,Science - Abstract
Cognitive reserve (CR) or brain reserve capacity explains why individuals with higher IQ, education, or occupational attainment have lower risks of developing dementia, Alzheimer's disease (AD) or vascular dementia (VaD). The CR hypothesis postulates that CR reduces the prevalence and incidence of AD or VaD. It also hypothesizes that among those who have greater initial cognitive reserve (in contrast to those with less reserve) greater brain pathology occurs before the clinical symptoms of disease becomes manifest. Thus clinical disease onset triggers a faster decline in cognition and function, and increased mortality among those with initial greater cognitive reserve. Disease progression follows distinctly separate pathological and clinical paths. With education as a proxy we use meta-analyses and qualitative analyses to review the evidence for the CR hypothesis.We searched PubMed, PsycoINFO, EMBASE, HealthStar, and Scopus databases from January 1980 to June 2011 for observational studies with clear criteria for dementia, AD or VaD and education. One hundred and thirty-three articles with a variety of study designs met the inclusion criteria. Prevalence and incidence studies with odds ratios (ORs), relative risks or original data were included in the meta-analyses. Other studies were reviewed qualitatively. The studies covered 437,477 subjects. Prevalence and incidence studies with pooled ORs of 2.61 (95%CI 2.21-3.07) and 1.88 (95%CI 1.51-2.34) respectively, showed low education increased the risk of dementia. Heterogeneity and sensitivity tests confirmed the evidence. Generally, study characteristics had no effect on conclusions. Qualitative analyses also showed the protective effects of higher education on developing dementia and with clinical disease onset hastening a decline in cognition and function, and greater brain pathology.This systematic review and meta-analyses covering a wide range of observational studies and diverse settings provides robust support for the CR hypothesis. The CR hypothesis suggests several avenues for dementia prevention.
- Published
- 2012
- Full Text
- View/download PDF
21. Coordinating environmental genomics and geochemistry reveals metabolic transitions in a hot spring ecosystem.
- Author
-
Wesley D Swingley, D'Arcy R Meyer-Dombard, Everett L Shock, Eric B Alsop, Heinz D Falenski, Jeff R Havig, and Jason Raymond
- Subjects
Medicine ,Science - Abstract
We have constructed a conceptual model of biogeochemical cycles and metabolic and microbial community shifts within a hot spring ecosystem via coordinated analysis of the "Bison Pool" (BP) Environmental Genome and a complementary contextual geochemical dataset of ~75 geochemical parameters. 2,321 16S rRNA clones and 470 megabases of environmental sequence data were produced from biofilms at five sites along the outflow of BP, an alkaline hot spring in Sentinel Meadow (Lower Geyser Basin) of Yellowstone National Park. This channel acts as a >22 m gradient of decreasing temperature, increasing dissolved oxygen, and changing availability of biologically important chemical species, such as those containing nitrogen and sulfur. Microbial life at BP transitions from a 92 °C chemotrophic streamer biofilm community in the BP source pool to a 56 °C phototrophic mat community. We improved automated annotation of the BP environmental genomes using BLAST-based Markov clustering. We have also assigned environmental genome sequences to individual microbial community members by complementing traditional homology-based assignment with nucleotide word-usage algorithms, allowing more than 70% of all reads to be assigned to source organisms. This assignment yields high genome coverage in dominant community members, facilitating reconstruction of nearly complete metabolic profiles and in-depth analysis of the relation between geochemical and metabolic changes along the outflow. We show that changes in environmental conditions and energy availability are associated with dramatic shifts in microbial communities and metabolic function. We have also identified an organism constituting a novel phylum in a metabolic "transition" community, located physically between the chemotroph- and phototroph-dominated sites. The complementary analysis of biogeochemical and environmental genomic data from BP has allowed us to build ecosystem-based conceptual models for this hot spring, reconstructing whole metabolic networks in order to illuminate community roles in shaping and responding to geochemical variability.
- Published
- 2012
- Full Text
- View/download PDF
22. Analysis of determinants for in vitro resistance to the small molecule deubiquitinase inhibitor b-AP15.
- Author
-
Mofers A, Perego P, Selvaraju K, Gatti L, Gullbo J, Linder S, and D'Arcy P
- Subjects
- Antineoplastic Agents pharmacology, Bortezomib pharmacology, Colonic Neoplasms drug therapy, Glutathione metabolism, Humans, Tumor Cells, Cultured, Apoptosis drug effects, Azepines pharmacology, Benzylidene Compounds pharmacology, Cell Proliferation drug effects, Colonic Neoplasms pathology, Drug Resistance, Neoplasm, Proteasome Inhibitors pharmacology
- Abstract
Background: b-AP15/VLX1570 are small molecule inhibitors of the ubiquitin specific peptidase 14 (USP14) and ubiquitin carboxyl-terminal hydrolase 5 (UCHL5) deubiquitinases (DUBs) of the 19S proteasome. b-AP15/VLX1570 have been shown to be cytotoxic to cells resistant to bortezomib, raising the possibility that this class of drugs can be used as a second-line therapy for treatment-resistant multiple myeloma. Limited information is available with regard to potential resistance mechanisms to b-AP15/VLX1570., Results: We found that b-AP15-induced cell death is cell-cycle dependent and that non-cycling tumor cells may evade b-AP15-induced cell death. Such non-cycling cells may re-enter the proliferative state to form colonies of drug-sensitive cells. Long-term selection of cells with b-AP15 resulted in limited drug resistance (~2-fold) that could be reversed by buthionine sulphoximine, implying altered glutathione (GSH) metabolism as a resistance mechanism. In contrast, drug uptake and overexpression of drug efflux transporters were found not to be associated with b-AP15 resistance., Conclusions: The proteasome DUB inhibitors b-AP15/VLX1570 are cell cycle-active. The slow and incomplete development of resistance towards these compounds is an attractive feature in view of future clinical use., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2019
- Full Text
- View/download PDF
23. Elevation of proteasomal substrate levels sensitizes cells to apoptosis induced by inhibition of proteasomal deubiquitinases.
- Author
-
Sun C, Roboti P, Puumalainen MR, Fryknäs M, Wang X, D'Arcy P, Hult M, High S, Linder S, and Swanton E
- Subjects
- Cysteine metabolism, Cysteine pharmacology, Cytoprotection drug effects, Endoplasmic Reticulum drug effects, Endoplasmic Reticulum metabolism, HCT116 Cells, HeLa Cells, Humans, Molecular Weight, Piperidones pharmacology, Polyubiquitin metabolism, Proteasome Inhibitors pharmacology, Protein Transport drug effects, Proteolysis drug effects, Saposins metabolism, Substrate Specificity drug effects, Ubiquitin-Specific Proteases metabolism, Apoptosis, Proteasome Endopeptidase Complex metabolism, Ubiquitin-Specific Proteases antagonists & inhibitors
- Abstract
Inhibitors of the catalytic activity of the 20S proteasome are cytotoxic to tumor cells and are currently in clinical use for treatment of multiple myeloma, whilst the deubiquitinase activity associated with the 19S regulatory subunit of the proteasome is also a valid target for anti-cancer drugs. The mechanisms underlying the therapeutic efficacy of these drugs and their selective toxicity towards cancer cells are not known. Here, we show that increasing the cellular levels of proteasome substrates using an inhibitor of Sec61-mediated protein translocation significantly increases the extent of apoptosis that is induced by inhibition of proteasomal deubiquitinase activity in both cancer derived and non-transformed cell lines. Our results suggest that increased generation of misfolded proteasome substrates may contribute to the mechanism(s) underlying the increased sensitivity of tumor cells to inhibitors of the ubiquitin-proteasome system.
- Published
- 2014
- Full Text
- View/download PDF
24. Oncogenic functions of the cancer-testis antigen SSX on the proliferation, survival, and signaling pathways of cancer cells.
- Author
-
D'Arcy P, Maruwge W, Wolahan B, Ma L, and Brodin B
- Subjects
- Cell Line, Tumor, Humans, Neoplasm Proteins genetics, Neoplasms metabolism, RNA, Small Interfering, Repressor Proteins genetics, Cell Proliferation, Cell Survival immunology, MAP Kinase Signaling System immunology, Neoplasm Proteins immunology, Neoplasms pathology, Oncogenes, Repressor Proteins immunology
- Abstract
SSX is a transcription factor with elusive oncogenic functions expressed in a variety of human tumors of epithelial and mesenchymal origin. It has raised substantial interest as a target for cancer therapy since it elicits humoral responses and displays restricted expression to cancer, spermatogonia and mesenchymal stem cells. Here, we investigated the oncogenic properties of SSX by employing a RNA interference to knock-down the endogenous expression of SSX in melanoma and osteosarcoma cell lines. Depletion of SSX expression resulted in reduced proliferation with cells accumulating in the G1 phase of the cell cycle. We found that the growth promoting and survival properties of SSX are mediated in part though modulation of MAPK/Erk and Wnt signaling pathways, since SSX silencing inhibited Erk-mediated signaling and transcription of cMYC and Akt-1. We also found that SSX forms a transient complex with β-catenin at the G1-S phase boundary resulting in the altered expression of β-catenin target genes such as E-cadherin, snail-2 and vimentin, involved in epithelial-mesenchymal transitions. Importantly the silencing of SSX expression in in vivo significantly impaired the growth of melanoma tumor xenografts. Tumor biopsies from SSX silenced tumors displayed reduced cyclin A staining, indicative of low proliferation and predominantly cycloplasmic β-catenin compared to SSX expressing tumors. The present study demonstrates a previously unknown function of SSX, that as an oncogene and as a tumor target for the development of novel anti-cancer drugs.
- Published
- 2014
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.