34 research outputs found

    Improving clinical outcomes for patients with locally advanced non-small cell lung cancer treated with photon and proton radiotherapy

    Get PDF
    Objectives To identify mechanisms improving clinical outcomes for patients with unresectable locally advanced non-small-cell lung cancer (LA-NSCLC) treated with photon and proton radiotherapy. Strategies explored include 1. Investigating using routine healthcare datasets to estimate survival outcomes for patients with LA-NSCLC treated with definitive radiotherapy, in order to assess the effectiveness of current strategies; 2. Assessing the physical advantages of protons by conducting a retrospective planning study comparing volumetric modulated arc therapy (VMAT) and pencil beam scanning (PBS) proton plans of superior sulcus tumours (SSTs), a rare subset of LA-NSCLC; 3. Exploring potential biological advantages of protons by examining major cell death pathways following XRT, high and low linear energy transfer (LET) proton irradiation of NSCLC cells. Methods Workflow 1: LA-NSCLC patients receiving definitive radiotherapy were identified. For each, key time points (date of diagnosis, recurrence, death or last clinical encounter) were used to calculate overall survival (OS) and progression free survival (PFS) from manual-data (hospital notes) and compared to estimated OS and PFS from routine-data (electronic databases). Dataset correlations were then tested to establish if routine-data were a reliable proxy measure for manual-data. Workflow 2: Patients with SSTs treated with 4D radiotherapy were identified. Tumour motion was assessed and excluded if >5 mm. Comparative VMAT and PBS plans were generated retrospectively. Robustness analysis was assessed for both plans involving: 1. 5 mm geometric uncertainty scenarios, with an additional 3.5% range uncertainty for proton plans; 2. verification plans at breathing extremes. Comparative dosimetric and robustness analyses were carried out. Workflow 3: Human NSCLC cell lines were irradiated with single doses of 2-15 Gy photon radiotherapy, high- or low-linear energy transfer (LET) protons (12 keV/µm and 1 keV/µm, respectively) and analysed 24-144 hours post-irradiation. DNA damage foci and cell death mechanisms were investigated. Results Workflow 1: In forty-three patients, routine data underestimated PFS by 0.09 months (p=0.86; 95% CI -0.86-1.03) and OS by 1.02 months (p=0.00; 95% CI 0.34-1.69) but there was good correlation with a Pearson correlation coefficient of 0.94 (p=0.00, 95% CI 0.90-0.97) for PFS and 0.97 (p= 0.00, 95% CI 0.95-0.98) for OS. Workflow 2: In ten patients, both modalities achieved similar target coverage with mean clinical target volume D95 of 98.1% + 0.4 (97.5-98.8) and 98.4% + 0.2 (98.1-98.9) for PBS and VMAT plans, respectively. The same four PBS and VMAT plans failed robustness. Proton plans significantly reduced mean lung dose (by 21.9%), lung V5, V10, V20 (by 47.9%, 36.4%, 12.1%, respectively), mean heart dose (by 21.4%) and vertebra dose (by 29.2%) (p<0.05). Workflow 3: XRT predominantly induced mitotic catastrophe, autophagy and senescence. Senescence, established via the p53/p21 pathway, was the major cell death pathway by which protons more effectively reduce clonogenic potential compared to XRT in NSCLC cell lines. High LET protons at a dose of 10 Gy(RBE) resulted in the lowest cell survival. The mechanisms driving the LET- and dose-dependent senescence was unclear but did not appear to be related to differential DNA repair machineries. Conclusions Proton radiotherapy could be pivotal in improving outcomes in select cases of LA-NSCLC. These studies demonstrate that 1. survival-outcomes are reliably estimated by routine data and such a methodology could enable rapid outcomes analysis to keep pace with trial development; 2. robust PBS plans are achievable in carefully selected patients and considerable dose reductions to the lung, heart and thoracic vertebra are possible without compromising target coverage; 3. Identification of LET- and dose-dependent proton-induced cellular senescence may guide radiotherapy optimisation and drug-radiotherapy combinations, maximising tumour cell kill. This work contributes to important preliminary research required to understand the physical and biological strengths and weaknesses prior to trials

    Isolation of salinity tolerant genes from the mangrove plant, Bruguiera cylindrica by using suppression subtractive hybridization (SSH) and bacterial functional screening

    Get PDF
    In this study, we have identified and isolated 126 salinity tolerant cDNAs from the root of a mangrove plant, Bruguiera cylindrica (L.) Blume by using suppression subtractive hybridization (SSH) and bacterial functional screening. Sequencing of 51 subtracted cDNA clones that were differentially expressed in the root of B. cylindrica exposed to 20 parts per thousand (ppt) NaCl water revealed 10 tentative unique genes (TUGs) with putative functions in protein synthesis, storage and destination, metabolism, intracellular trafficking and other functions; and 9 unknown proteins. Meanwhile, the 75 cDNA sequences of B. cylindrica that conferred salinity tolerance to Escherichia coli consisted of 29 TUGs with putative functions in transportation, metabolism and other functions; and 33 with unknown functions. Both approaches yielded 42 unique sequencess that have not been reported else where to be stress related and might provide further understanding of adaptations of this plant to salinity stress

    Accessing the Impact of Socioeconomic Factors on Suicide : A Panel Study in ASEAN Countries

    Get PDF
    This paper aims to investigate the impact of socioeconomic factors on suicide using panel data for 10 ASEAN countries over the time period 2000 to 2019. The linear and non-linear nexus between socioeconomic factors (GDP per capita, current health expenditure, unemployment rate fertility rate, female labour force participation rate and alcohol consumption per capita) and ASEAN suicide rate are investigated using a panel data from the World Health Organization and World Bank Data. The analysis conducted based on the panel unit root test, Pedroni cointegration test and panel ARDL estimation. The panel unit root tests showed the mixed results that the variables are stationary at I(0), I(1) or both. The Pedroni cointegration test found that there is a long-run relationship between variables in ASEAN countries. The findings of panel ARDL estimation indicates that all the variables are significant with ASEAN age-standardized total suicide rate. In addition, GDP per capita had U-shaped connection with age-standardized total suicide rate

    Online learning amidst covid-19 pandemic – explicating the nexus between learners’ characteristics, their learning environment and the learning outcomes in built environment studies

    Get PDF
    The onslaught of Covid-19 has fundamentally upended the landscape of learning in universities. Learners from diverse backgrounds were abruptly forced into the sphere of online learning. Therefore, question arises whether learners from different backgrounds or learners’ characteristics, together with their learning environment, would impact the outcomes of online learning. Using Astin’s Input-Environment-Outcome (I-E-O) model, this study aims to explicate the nexus between the learners’ characteristics, their learning environment and outcomes of online learning. For this purpose, the instrument on Benchmarking Best Practices in Web-Based Courses has been adopted to capture the perception of online learners amidst the pandemic. A survey was administered digitally to students of Built Environment studies, namely the Architecture and Quantity Surveying programmes. Data from 187 respondents were analysed utilising mean analysis, factor analysis, correlation, as well as hierarchical multiple regression. Findings revealed that learners’ characteristics did not correlate highly (r≤0.50) with either the learning environment or the learning outcomes. However, learning environment was found to correlate strongly (r≥0.50) with learning outcomes. Additionally, results from hierarchical multiple regression suggested that characteristics of learners, together with learning environment, positively influenced outcomes of online learning (R2 = 0.679, p < 0.01). This interesting result offered alternative empirical evidence when compared to past study

    Assessing the Relationship between Socio-demographic, Clinical Profile and Financial Toxicity: Evidence from Cancer Survivors in Sarawak

    Get PDF
    Background: Patient’s financial ability is always the most critical imputes to treatment choice and adherence; as it translates into health outcomes such as survival rate and quality of life. Cancer care is likely to affect the patient’s financial well-being, putting huge financial pressure to the families. Therefore, it is imperative to understand the confounding factors of financial toxicity among cancer survivors along the course of survivorship. Methods: This study was designed in the form of cross-sectional analysis, in which, cancer survivors were recruited from the Sarawak General Hospital, the largest tertiary and referral public hospital in Sarawak. To capture the financial toxicity of the cancer survivors, the Comprehensive Score for Financial Toxicity (COST) instrument in its validated form was adopted. Multivariable logistic regression analysis was applied to determine the relationship between financial toxicity (FT) and its predictors. Results: The median age of the 461 cancer survivors was 56 while the median score of COST was 22.0. Besides, finding from multivariable logistic regression revealed that low income households (OR: 6.893, 95% CI, 3.109-15.281) were susceptible to higher risk of financial toxicity, while elderly survivors above 50 years old reported a lower risk in financial toxicity. Also, survivors with secondary schooling (OR:0.240; 95%CI, 0.110-0.519) and above [College or university (OR: 0.242; 95% CI, 0.090-0.646)] suffer a lower risk of FT. Conclusion: Financial toxicity was found to be associated with survivors age, household income and educational level. In the context of cancer treatment within public health facility, younger survivors, households from B40 group and individual with educational attainment below the first level schooling in the Malaysian system of education are prone to greater financial toxicity. Therefore, it is crucial for healthcare policymakers and clinicians to deliberate the plausible risk of financial toxicity borne by the patient amidst the treatment process

    Entomologic and molecular investigation into Plasmodium vivax transmission in Singapore, 2009

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Singapore has been certified malaria free since November 1982 by the World Health Organization and despite occasional local transmission, the country has maintained the standing. In 2009, three clusters of malaria cases were reported in Singapore.</p> <p>Methods</p> <p>Epidemiological, entomological and molecular studies were carried out to investigate the three clusters, namely Mandai-Sungei Kadut, Jurong Island and Sembawang.</p> <p>Results</p> <p>A total of 29 malaria patients, with no recent travel history, were reported in the three clusters. Molecular analysis based on the <it>msp3α </it>and <it>msp1 </it>genes showed two independent local transmissions: one in Mandai-Sungei Kadut and another in Sembawang. Almost all cases within each cluster were epidemiologically linked. In Jurong Island cluster, epidemiological link remains uncertain, as almost all cases had a unique genetic profile. Only two cases shared a common profile and were found to be linked to the Mandai-Sungei Kadut cluster. Entomological investigation found <it>Anopheles sinensis </it>to be the predominant Anopheline in the two areas where local transmission of <it>P. vivax </it>was confirmed. <it>Anopheles sinensis </it>was found to be attracted to human bait and bites as early as 19:45 hrs. However, all <it>Anopheles </it>mosquitoes caught were negative for sporozoites and oocysts by dissection.</p> <p>Conclusion</p> <p>Investigation of <it>P. vivax </it>cases from the three cluster areas confirmed the occurrence of local transmission in two areas. Although <it>An. sinensis </it>was the predominant Anopheline found in areas with confirmed transmission, the vector/s responsible for the outbreaks still remains cryptic.</p

    First Report from the Asian Rotavirus Surveillance Network

    Get PDF
    Rotavirus remains the most common cause of severe, dehydrating diarrhea among children worldwide. Several rotavirus vaccines are under development. Decisions about new vaccine introduction will require reliable data on disease impact. The Asian Rotavirus Surveillance Network, begun in 2000 to facilitate collection of these data, is a regional collaboration of 36 hospitals in nine countries or areas that conduct surveillance for rotavirus hospitalizations using a uniform World Health Organization protocol. We summarize the Network's organization and experience from August 2001 through July 2002. During this period, 45% of acute diarrheal hospitalizations among children 0–5 years were attributable to rotavirus, higher than previous estimates. Rotavirus was detected in all sites year-round. This network is a novel, regional approach to surveillance for vaccine-preventable diseases. Such a network should provide increased visibility and advocacy, enable more efficient data collection, facilitate training, and serve as the paradigm for rotavirus surveillance activities in other regions

    Incident type 2 diabetes attributable to suboptimal diet in 184 countries

    Get PDF
    The global burden of diet-attributable type 2 diabetes (T2D) is not well established. This risk assessment model estimated T2D incidence among adults attributable to direct and body weight-mediated effects of 11 dietary factors in 184 countries in 1990 and 2018. In 2018, suboptimal intake of these dietary factors was estimated to be attributable to 14.1 million (95% uncertainty interval (UI), 13.8–14.4 million) incident T2D cases, representing 70.3% (68.8–71.8%) of new cases globally. Largest T2D burdens were attributable to insufficient whole-grain intake (26.1% (25.0–27.1%)), excess refined rice and wheat intake (24.6% (22.3–27.2%)) and excess processed meat intake (20.3% (18.3–23.5%)). Across regions, highest proportional burdens were in central and eastern Europe and central Asia (85.6% (83.4–87.7%)) and Latin America and the Caribbean (81.8% (80.1–83.4%)); and lowest proportional burdens were in South Asia (55.4% (52.1–60.7%)). Proportions of diet-attributable T2D were generally larger in men than in women and were inversely correlated with age. Diet-attributable T2D was generally larger among urban versus rural residents and higher versus lower educated individuals, except in high-income countries, central and eastern Europe and central Asia, where burdens were larger in rural residents and in lower educated individuals. Compared with 1990, global diet-attributable T2D increased by 2.6 absolute percentage points (8.6 million more cases) in 2018, with variation in these trends by world region and dietary factor. These findings inform nutritional priorities and clinical and public health planning to improve dietary quality and reduce T2D globally.publishedVersio

    Incident type 2 diabetes attributable to suboptimal diet in 184 countries

    Get PDF
    The global burden of diet-attributable type 2 diabetes (T2D) is not well established. This risk assessment model estimated T2D incidence among adults attributable to direct and body weight-mediated effects of 11 dietary factors in 184 countries in 1990 and 2018. In 2018, suboptimal intake of these dietary factors was estimated to be attributable to 14.1 million (95% uncertainty interval (UI), 13.8–14.4 million) incident T2D cases, representing 70.3% (68.8–71.8%) of new cases globally. Largest T2D burdens were attributable to insufficient whole-grain intake (26.1% (25.0–27.1%)), excess refined rice and wheat intake (24.6% (22.3–27.2%)) and excess processed meat intake (20.3% (18.3–23.5%)). Across regions, highest proportional burdens were in central and eastern Europe and central Asia (85.6% (83.4–87.7%)) and Latin America and the Caribbean (81.8% (80.1–83.4%)); and lowest proportional burdens were in South Asia (55.4% (52.1–60.7%)). Proportions of diet-attributable T2D were generally larger in men than in women and were inversely correlated with age. Diet-attributable T2D was generally larger among urban versus rural residents and higher versus lower educated individuals, except in high-income countries, central and eastern Europe and central Asia, where burdens were larger in rural residents and in lower educated individuals. Compared with 1990, global diet-attributable T2D increased by 2.6 absolute percentage points (8.6 million more cases) in 2018, with variation in these trends by world region and dietary factor. These findings inform nutritional priorities and clinical and public health planning to improve dietary quality and reduce T2D globally
    corecore