ORCID Profile
0000-0002-6990-1785
Current Organisation
Peter MacCallum Cancer Centre
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Publisher: ACTAPRESS
Date: 2012
Publisher: IEEE
Date: 06-2012
Publisher: Wiley
Date: 09-01-2020
Abstract: According to recent statistics from the World Health Organization, 23% of people aged 18 years and over are not sufficiently physically active. Strangely, this is at a time when, due to the improvement in sensor technology, physical activity programs that track physical activity have become popular. However, some participants who enroll in these programs cheat by manipulating the data they enter. This can be discouraging for other participants, also invalidating the overall accuracy of program outcomes. Therefore, detecting these participants and discarding their manipulated entries is important in order to maintain the quality of the program. Currently, most of these physical activity programs use manual processes to detect and reject fraudulent step entries by reviewing the participant's demographic profiles along with their longitudinal step count performance data. In this study, a process, including two parallel models for detecting person of interest characteristics and abnormal step count entries, is developed. The first model uses the penalized logistic regression with Synthetic Minority Over-s ling Technique subs ling to address the imbalance in the proportion of genuine and persons of interest. Having a highly imbalanced distribution between genuine and person of interest profiles makes this task more challenging. The second model uses a variety of outlier detection methods to detect and reject abnormal step entries based on previously entered data. This process will be more efficient and productive compared to the current manual system and will support better decision-making in the future. The proposed system can be applied for other fraud detection applications after suitable adjustments.
Publisher: Springer Science and Business Media LLC
Date: 29-06-2022
DOI: 10.1038/S41698-022-00288-2
Abstract: Hormone receptor expression is a characteristic of low-grade serous ovarian carcinoma (LGSOC). Studies investigating estrogen receptor (ER) and progesterone receptor (PR) expression levels suggest its prognostic and predictive significance, although their associations with key molecular aberrations are not well understood. As such, we sought to describe the specific genomic profiles associated with different ER/PR expression patterns and survival outcomes in a cohort of patients with advanced disease. The study comprised fifty-five advanced-staged (III/IV) LGSOCs from the Canadian Ovarian Experimental Unified Resource (COEUR) for which targeted mutation sequencing, copy-number aberration, clinical and follow-up data were available. ER, PR, and p16 expression were assessed by immunohistochemistry. Tumors were ided into low and high ER/PR expression groups based on Allred scoring. Copy number analysis revealed that PR-low tumors (Allred score ) had a higher fraction of the genome altered by copy number changes compared to PR-high tumors ( p = 0.001), with cancer genes affected within specific loci linked to altered peptidyl-tyrosine kinase, MAP-kinase, and PI3-kinase signaling. Cox regression analysis showed that ER-high ( p = 0.02), PR-high ( p = 0.03), stage III disease ( p = 0.02), low residual disease burden ( p = 0.01) and normal p16 expression ( p .001) were all significantly associated with improved overall survival. This study provides evidence that genomic aberrations are linked to ER/PR expression in primary LGSOC.
Publisher: JMIR Publications Inc.
Date: 19-10-2018
DOI: 10.2196/JMIR.9058
Publisher: Portland Press Ltd.
Date: 07-2019
DOI: 10.1042/BSR20182313
Abstract: Lack of insulin or insulin resistance (IR) plays a central role in diabetes mellitus and makes diabetics prone to acute ischemic heart disease (AIHD). It has likewise been found that many cancer patients, including prostate cancer patients die of AIHD. Previously it has been delineated from our laboratory that dermcidin could induce anomalous platelet aggregation in AIHD and also impaired nitric oxide and insulin activity and furthermore dermcidin was also found in a few types of cancer patients. To determine the role of this protein in prostatic malignancy, a retrospective case–control study was conducted and blood was collected from prostate cancer patients and healthy normal volunteers. So, we measured the level of dermcidin protein and analyzed the IR by Homeostasis Model Assessment (HOMA) score calculation. Nitric oxide was measured by methemoglobin method. HDL, glycated hemoglobin (HbA1c), BMI, hs-cTroponin-T were measured for the validation of the patients’ status in the presence of Dermcidin isoform-2 (DCN-2). Multiple logistic regression model adjusted for age and BMI identified that the HOMA score was significantly elevated in prostate cancer patients (OR = 7.19, P& .001). Prostate cancer patients are associated with lower level of NO and higher level of both proteins dermcidin (OR = 1.12, P& .001) and hs-TroponinT (OR = 1.76, P& .001). From the results, it can be interpreted that IR plays a key role in the pathophysiology of prostate cancer where dermcidin was the cause of IR through NO inhibition leading to AIHD was also explained by high-sensitive fifth generation cTroponin-T (hs-cTroponinT) and HbA1c level which are associated with endothelial dysfunction.
Publisher: Cold Spring Harbor Laboratory
Date: 05-09-2022
DOI: 10.1101/2022.09.02.506444
Abstract: For more than two decades attempts have been made to identify a subset of women diagnosed with lesions with uncertain malignant potential (B3 lesions) who could safely be observed rather than being treated with surgical excision and/or chemoprevention. Various histopathological, clinical and imaging parameters for risk recommendation have been evaluated, with little impact on clinical practice. The primary reason for surgery is to rule out an upgrade lesion to either ductal carcinoma in situ (DCIS) or invasive breast cancer (IBC). While on average 30% of these patients are upgraded after diagnostic biopsy, a large number are over treated,making this an important harm of screening. Here we evaluated stromal lymphocytes from B3 biopsies (n=264) as a predictive biomarker for upgrade. A higher number of stromal lymphocytes were observed in upgraded B3 lesions than non-upgraded (p 0.01, zero inflated binomial model) for both ductal and papillary lesions (n=174). This observation was validated in an independent cohort (p .001, p .05, zero binomial model, ductal and papillary lesions, respectively) (n=90). Our data suggested that the presence of ≥5% of lymphocytes in the surrounding specialised stroma of B3 lesions are predictive of B3 lesions being upgraded with a specificity of 93% and 87% in our discovery and validation cohorts, respectively. The area under the curve (AUC) for the discovery cohort using lymphocyte count and age as variables was 0.77 and was validated with an AUC of 0.81 in the validation cohort. In conclusion, we can identify a subset of the patients at risk of upgrade with high specificity. Assessing the tumour microenvironment including stromal lymphocytes may contribute to reducing unnecessary surgeries in the clinic.
Publisher: ZappyLab, Inc.
Date: 03-2019
Publisher: Public Library of Science (PLoS)
Date: 02-11-2018
Publisher: IEEE
Date: 09-2012
Publisher: Human Kinetics
Date: 04-2019
Abstract: To evaluate the impact of an online workplace program that promotes physical activity and health, while focusing on performance measures relating to physical activity, nutrition, and overall health. The large s le size (more than 18,000 participants) allowed the use of text mining and machine-learning methods to determine what descriptions of the program identify successful outcomes, and hierarchical linear models to determine the most beneficial program modules and features. The program increased overall health and awareness of levels of physical activity and nutrition, especially for people who scored low on these measures initially. Interestingly, although physical activity is the most popular program module, the daily step-tracking process was associated with smaller improvements in overall health. This study finds that the Virgin Pulse Global Challenge is an effective workplace intervention for improving overall health and awareness of physical activity and nutrition. Effectiveness relates to the holistic approach adopted rather than to in idual modules in isolation. Future evaluations of workplace health and exercise programs should explore a variety of outcome measures within the rich context provided by open-ended participant experience feedback. In addition, a control group and a follow-up study are required.
Publisher: Wiley
Date: 29-09-2021
DOI: 10.1002/CAM4.4246
Abstract: Higher rates of death by suicide are recognized both in in iduals of any age with cancer and, separately, among adolescents and young adults (AYA) without cancer. Given this intersection, identifying risk factors associated with suicidal risk among AYA with cancer is critical. To identify characteristics associated with suicide among AYA with cancer. A retrospective analysis of AYA (aged 15–39) during 1975–2016 from the Surveillance, Epidemiology, and End Results database was conducted. Clinical and demographic factors associated with death by suicide among the AYA cancer population were compared to (i) US population normative data (standardized mortality ratios [SMRs]) and (ii) other AYA in iduals with cancer (odds ratios). In total, 922 suicides were found in 500,366 AYA with cancer (0.18%), observed for 3,198,261 person‐years. The SMR for AYA with cancer was 34.1 (95% confidence interval [CI]: 31.4–36.9). Suicide risk was particularly high in females (SMR = 43.4, 95% CI: 37.2–50.4), unmarried persons (SMR = 50.6, 95% CI: 44.7–57.1), those with metastatic disease (SMR = 45.2, 95% CI: 33.1–60.3), or certain histological subtypes (leukemia, central nervous system, and soft tissue sarcoma). Risk generally reduced over time, however remained elevated ≥5 years following a cancer diagnosis (SMR 5 years = 28.1, 95% CI: 25.4–31.0). When comparing those who died from suicide and those who did not, the following factors demonstrated significant associations: sex (males females), race (White ethnicity Black/other ethnicity), relationship status (never married other), and disease stage (distant localized). Death due to suicide/non‐accidental injury is high compared to normative data, requiring increased awareness among health‐care providers, suicide risk monitoring in AYA, and appropriately tailored psychosocial interventions.
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 03-2015
Publisher: Public Library of Science (PLoS)
Date: 04-05-2022
DOI: 10.1371/JOURNAL.PONE.0267203
Abstract: Conservation areas are critical for bio ersity conservation, but few citizen science studies have evaluated their efficiency. In the absence of thorough survey data, this study assessed which species benefit most from conservation areas using citizen science bird counts extracted from the Atlas of Living Australia. This was accomplished by fitting temporal models using citizen science data taken from ALA for the years 2010–2019 using the INLA approach. The trends for six resident shorebird species were compared to those for the Australian Pied Oystercatcher, with the Black-fronted Dotterel, Red-capped Dotterel, and Red-kneed Dotterel exhibiting significantly steeper increasing trends. For the Black-fronted Dotterel, Masked Lapwing, and Red-kneed Dotterel, steeper rising trends were recorded in conservation areas than in other locations. The Dotterel species’ conservation status is extremely favourable. This study demonstrates that, with some limits, statistical models can be used to track the persistence of resident shorebirds and to investigate the factors affecting these data.
Publisher: Springer International Publishing
Date: 13-10-2015
DOI: 10.1007/978-3-319-10984-8_3
Abstract: Array comparative genomic hybridization (aCGH) is one of the techniques that can be used to detect copy number variations in DNA sequences in high resolution. It has been identified that abrupt changes in the human genome play a vital role in the progression and development of many complex diseases. In this study we propose two distinct hybrid algorithms that combine efficient sequential change-point detection procedures (the Shiryaev-Roberts procedure and the cumulative sum control chart (CUSUM) procedure) with the Cross-Entropy method, which is an evolutionary stochastic optimization technique to estimate both the number of change-points and their corresponding locations in aCGH data. The proposed hybrid algorithms are applied to both artificially generated data and real aCGH experimental data to illustrate their usefulness. Our results show that the proposed methodologies are effective in detecting multiple change-points in biological sequences of continuous measurements.
Publisher: Wiley
Date: 2021
DOI: 10.1111/IMJ.14765
Abstract: Studies have reported significant differences in baseline characteristics and outcomes of metastatic colorectal cancer (mCRC) patients when managed in private versus public hospitals. To compare disease, treatment and survival outcomes of patients with mCRC in public versus private hospitals in South Australia (SA). Analysis of prospectively collected data from the SA mCRC Registry. Patterns of care and outcome data according to location of care and socioeconomic status based on Index of Relative Socio-Economic Advantage and Disadvantage were analysed. A total of 3470 patients' data was analysed during February 2006-January 2015. The majority (70%) of patients received treatment in public hospitals. Patients in the upper 50% for Index of Relative Socio-Economic Advantage and Disadvantage score were more likely to receive treatment at a private hospital (41.2% vs 21.56%) compared to <50%. Public patients had higher burden of disease (10.49% vs 7.41%, P = 0.005). Public patients received less treatment compared to the private patients (odds ratio = 0.48 (0.38-0.61), P = 0.01) and rates of surgical resections were lower in public patients. After adjusting for the covariates, public patients survive 1.33 months (P = 0.025) shorter than private patients with follow-up time of 5 years. Patients receiving metastasectomy and more than three lines of treatment were shown to have the greatest survival benefit. Public patients have a higher burden of disease and in comparison are less likely to receive systemic therapy and have lower survival than patients treated in private hospitals.
Publisher: Elsevier BV
Date: 03-2020
Publisher: JMIR Publications Inc.
Date: 26-09-2017
Abstract: orkplace programs designed to improve the health and psychological well-being of employees are becoming increasingly popular. However, there are mixed reports regarding the effectiveness of such programs and little analysis of what helps people to engage with such programs. his evaluation of a particularly broad, team-based, digital health and well-being program uses mixed methods to identify the elements of the program that reduce work stress and promote psychological well-being, sleep quality, and productivity of employees. articipation in the Virgin Pulse Global Challenge program during May to September 2016 was studied. Self-reported stress, sleep quality, productivity, and psychological well-being data were collected both pre- and postprogram. Participant experience data were collected through a third final survey. However, the response rates for the last 2 surveys were only 48% and 10%, respectively. A random forest was used to estimate the probability of the completion of the last 2 surveys based on the preprogram assessment data and the demographic data for the entire s le (N=178,350). The inverse of these estimated probabilities were used as weights in hierarchical linear models in an attempt to address any estimation bias caused by the low response rates. These linear models described changes in psychological well-being, stress, sleep, and productivity over the duration of the program in relation to gender and age, engagement with each of the modules, each of the program features, and participant descriptions of the Virgin Pulse Global Challenge. A 0.1% significance level was used due to the large s le size for the final survey (N=18,653). he final analysis suggested that the program is more beneficial for older people, with 2.9% greater psychological well-being improvements observed on average in the case of women than men (P .001). With one exception, all the program modules contributed significantly to the outcome measures with the following average improvements observed: psychological well-being, 4.1%-6.0% quality of sleep, 3.2%-6.9% work-related stress, 1.7%-6.8% and productivity, 1.9%-4.2%. However, only 4 of the program features were found to have significant associations with the outcome measures with the following average improvements observed: psychological well-being, 3.7%-5.6% quality of sleep, 3.4%-6.5% work-related stress, 4.1%-6.4% and productivity, 1.6%-3.2%. Finally, descriptions of the Virgin Pulse Global Challenge produced 5 text topics that were related to the outcome measures. Healthy lifestyle descriptions showed a positive association with outcomes, whereas physical activity and step count tracking descriptions showed a negative association with outcomes. he complementary use of qualitative and quantitative survey data in a mixed-methods analysis provided rich information that will inform the development of this and other programs designed to improve employee health. However, the low response rates and the lack of a control group are limitations, despite the attempts to address these problems in the analysis.
Publisher: ZappyLab, Inc.
Date: 20-09-2018
DOI: 10.17504/PROTOCOLS.IO.TSVENE6
Abstract: Background Physical activity reduces the risk of noncommunicable diseases and is therefore an essential component of a healthy lifestyle. Regular engagement in physical activity can produce immediate and long term health benefits. However, physical activity levels are not as high as might be expected. For ex le, according to the global World Health Organization (WHO) 2017 statistics, more than 80% of the world's adolescents are insufficiently physically active. In response to this problem, physical activity programs have become popular, with step counts commonly used to measure program performance. Analysing step count data and the statistical modeling of this data is therefore important for evaluating in idual and program performance.This study reviews the statistical methods that used to model and evaluate physical activity programs, using step counts. Methods Adhering to PRISMA guidelines,this review systematically searched for relevant journal articles which were published between January 2000 and August 2017 in any of three databases (PubMed, PsycINFO and Web of Science). Only the journal articles which used a statistical model in analysing step counts for a healthy s le of participants, enrolled in an intervention involving physical exercise or a physical activity program, were included in this study. In these programs the activities considered were natural elements of everyday life rather than special activity interventions. Results This systematic review was able to identify 78 unique articles describing statistical models for analysing step counts obtained through physical activity programs. General linear models and generalized linear models were the most popular methods used followed by multilevel models, while structural equation modeling was only used for measuring the personal and psychological factors related to step counts. Surprisingly no use was made of time series analysis for analysing step count data. The review also suggested several strategies for the personalisation of physical activity programs. Conclusions Overall, it appears that the physical activity levels of people involved in such programs vary across in iduals depending on psychosocial, demographic, weather and climatic factors. Statistical models can provide a better understanding of the impact of these factors, allowing for the provision of more personalised physical activity programs, which are expected to produce better immediate and long-term outcomes for participants. It is hoped that this review will identify the statistical methods which are most suitable for this purpose.
Publisher: Springer Science and Business Media LLC
Date: 02-10-2022
DOI: 10.1245/S10434-022-12562-5
Abstract: In esophageal cancer (EC), there is a paucity of knowledge regarding the interplay between the tumor immune microenvironment and response to neoadjuvant treatment and, therefore, which factors may influence outcomes. Thus, our goal was to investigate the changes in the immune microenvironment with neoadjuvant treatment in EC by assessing the expression of immune related genes and their association with prognosis. We examined the transcriptome of paired pre- and post-neoadjuvant treated EC specimens. Based on these findings, we validated the presence of tumor-infiltrating neutrophils using CD15 + immunohistochemistry in a discovery cohort of patients with residual pathologic disease. We developed a nomogram as a predictor of progression-free survival (PFS) incorporating the variables CD15 + cell count, tumor regression grade, and tumor grade. After neoadjuvant treatment, there was an increase in genes related to myeloid cell differentiation and a poor prognosis associated with high neutrophil (CD15 + ) counts. Our nomogram incorporating CD15 + cell count was predictive of PFS with a C-index of 0.80 (95% confidence interval [CI] 0.68–0.9) and a concordance probability estimate (CPE) of 0.77 (95% CI 0.69–0.86), which indicates high prognostic ability. The C-index and CPE of the validation cohort were 0.81 (95% CI 0.69–0.91) and 0.78 (95% CI 0.7–0.86), respectively. Our nomogram incorporating CD15 + cell count can potentially be used to identify patients at high risk of recurrent disease and thus stratify patients who will benefit most from adjuvant treatment.
Publisher: Elsevier BV
Date: 2021
Publisher: Human Kinetics
Date: 08-2019
Abstract: Background : Despite holding great potential for addressing concerns regarding public health, recent systematic reviews have found effect sizes for interventions targeting physical activity to be small. Before interventions can be improved, the factors influencing outcomes must be identified. This systematic review aimed to identify predictors of success, measured in terms of engagement (eg, involvement duration) and health behavior change (eg, increased step counts), of workplace interventions targeting physical activity. Methods : A structured search of 3 databases (PubMed, PsycINFO, and Web of Science) was conducted to identify articles published between January 2000 and April 2017. For inclusion, articles needed to test a workplace intervention targeting physical activity and perform a quantitative analysis, identifying predictors of engagement or health behavior change. Results : Twenty-two studies were identified for review (median quality score = 70%). Demographic variables (eg, gender, age) were inconsistent predictors of success. However, employees in better health and physically active at baseline were found to have a greater likelihood of success. Conclusions : It appears that achieving successful results among employees at high risk of poor health outcomes remains a significant challenge for interventions. It is hoped that program developers can use this information to create effective interventions particularly for more sedentary employees.
Publisher: Cold Spring Harbor Laboratory
Date: 28-09-0011
DOI: 10.1101/2021.09.28.462220
Abstract: In the absence of comprehensive survey data this study used citizen science bird counts, extracted from the Atlas of Living Australia, to assess which species benefit most from protected areas. This was done by fitting temporal models using the Integrated Laplace Approximation (INLA) method. The trends for five resident shorebird species were compared to the Australian Pied Oystercatcher, with significantly steeper upward trends identified for the Black-fronted Dotterel, Red-capped Dotterel and Red-kneed Dotterel. Steeper upward trends were observed in protected than unprotected areas for the Black-fronted Dotterel, Masked Lapwing and Red-kneed Dotterel. This work suggests that, with some limitations, statistical models can be used with citizen science data for monitoring the persistence of resident shorebirds and for investigating factors that are impacting these data. The results for the Dotterel species in protected areas are particularly encouraging.
Publisher: Elsevier BV
Date: 05-2028
Publisher: Springer Science and Business Media LLC
Date: 11-10-2022
Location: United States of America
No related grants have been discovered for Madawa W Jayawardana.