995 resultados para 225
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Boron nitride nanotubes were functionalized by microperoxidase-11 in aqueous media, showing improved catalytic performance due to a strong electron coupling 10 between the active centre of microperoxidase-11 and boron nitride nanotubes. One main application challenge of enzymes as biocatalysts is molecular aggregation in the aqueous solution. This issue is addressed by immobilization of enzymes on solid supports which 15 can enhance enzyme stability and facilitate separation, and recovery for reuse while maintaining catalytic activity and selectivity. The protein-nanoparticle interactions play a key role in bio-nanotechnology and emerge with the development of nanoparticle-protein “corona”. Bio-molecular coronas provide a 20 unique biological identity of nanosized materials.1, 2 As a structural analogue to carbon nanotubes (CNTs), Boron nitride nanotubes have boron and nitrogen atoms distributed equally in hexagonal rings and exhibit excellent mechanical strength, unique physical properties, and chemical stability at high-temperatures. 25 The chemical inertness of BN materials suits to work in hazardous environments, making them an optimal candidate in practical applications in biological and medical field.3, 4
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Background: Few patients diagnosed with lung cancer are still alive 5 years after diagnosis. The aim of the current study was to conduct a 10-year review of a consecutive series of patients undergoing curative-intent surgical resection at the largest tertiary referral centre to identify prognostic factors. Methods: Case records of all patients operated on for lung cancer between 1998 and 2008 were reviewed. The clinical features and outcomes of all patients with non-small cell lung cancer (NSCLC) stage I-IV were recorded. Results: A total of 654 patients underwent surgical resection with curative intent during the study period. Median overall survival for the entire cohort was 37 months. The median age at operation was 66 years, with males accounting for 62.7 %. Squamous cell type was the most common histological subtype, and lobectomies were performed in 76.5 % of surgical resections. Pneumonectomy rates decreased significantly in the latter half of the study (25 vs. 16.3 %), while sub-anatomical resection more than doubled (2 vs. 5 %) (p < 0.005). Clinico-pathological characteristics associated with improved survival by univariate analysis include younger age, female sex, smaller tumour size, smoking status, lobectomy, lower T and N status and less advanced pathological stage. Age, gender, smoking status and tumour size, as well as T and N descriptors have emerged as independent prognostic factors by multivariate analysis. Conclusion: We identified several factors that predicted outcome for NSCLC patients undergoing curative-intent surgical resection. Survival rates in our series are comparable to those reported from other thoracic surgery centres. © 2012 Royal Academy of Medicine in Ireland.
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BACKGROUND. The authors compared gemcitabine and carboplatin (GC) with mitomycin, ifosfamide, and cisplatin (MIC) or mitomycin, vinblastine, and cisplatin (MVP) in patients with advanced nonsmall cell lung carcinoma (NSCLC). The primary objective was survival. Secondary objectives were time to disease progression, response rates, evaluation of toxicity, disease-related symptoms, World Health Organization performance status (PS), and quality of life (QoL). METHODS. Three hundred seventy-two chemotherapy-naïve patients with International Staging System Stage III/IV NSCLC who were ineligible for curative radiotherapy or surgery were randomized to receive either 4 cycles of gemcitabine (1000 mg/m2 on Days 1, 8, and 15) plus carboplatin (area under the serum concentration-time curve, 5; given on Day 1) every 4 weeks (the GC arm) or MIC/MVP every 3 weeks (the MIC/MVP arm). RESULTS. There was no significant difference in median survival (248 days in the MIC/MVP arm vs. 236 days in the GC arm) or time to progression (225 days in the MIC/MVP arm vs. 218 days in the GC arm) between the 2 treatment arms. The 2-year survival rate was 11.8% in the MIC/MVP arm and 6.9% in the GC arm. The 1-year survival rate was 32.5% in the MIC/MVP arm and 33.2% in the GC arm. In the MIC/MVP arm, 33% of patients responded (4 complete responses [CRs] and 57 partial responses [PRs]) whereas in the GC arm, 30% of patients responded (3 CRs and 54 PRs). Nonhematologic toxicity was comparable for patients with Grade 3-4 symptoms, except there was more alopecia among patients in the MIC/MVP arm. GC appeared to produce more hematologic toxicity and necessitated more transfusions. There was no difference in performance status, disease-related symptoms, of QoL between patients in the two treatment arms. Fewer inpatient stays for complications were required with GC. CONCLUSIONS. The results of the current study failed to demonstrate any difference in efficacy between the newer regimen of GC and the older regimens of MIC and MVP. © 2003 American Cancer Society.
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Although some research suggests that dog-assisted therapy may be beneficial for people with dementia living in residential aged care facilities, the intervention has not been adequately investigated. To address this shortcoming, we conducted a randomized controlled trial of dog-assisted therapy versus a human-therapist-only intervention for this population. Fifty-five residents with mild to moderate dementia living in three Australian residential aged care facilities completed an 11-week trial of the interventions. Allocation to the intervention was random and participants completed validated measures of mood, psychosocial functioning, and quality of life (QOL), both prior to and following the intervention. No adverse events were associated with the dog-assisted intervention, and following it participants who had worse baseline depression scores demonstrated significantly improved depression scores relative to participants in the human-therapist-only intervention. Participants in the dogassisted intervention also showed significant improvements on a measure of QOL in one facility compared with those in the human-therapist-only group (although worse in another facility that had been affected by an outbreak of gastroenteritis). This study provides some evidence that dog-assisted therapy may be beneficial for some residents of aged care facilities with dementia.
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INTRODUCTION: Performance status (PS) 2 patients with non-small cell lung cancer (NSCLC) experience more toxicity, lower response rates, and shorter survival times than healthier patients treated with standard chemotherapy. Paclitaxel poliglumex (PPX), a macromolecule drug conjugate of paclitaxel and polyglutamic acid, reduces systemic exposure to peak concentrations of free paclitaxel and may lead to increased concentrations in tumors due to enhanced vascular permeability. METHODS: Chemotherapy-naive PS 2 patients with advanced NSCLC were randomized to receive carboplatin (area under the curve = 6) and either PPX (210 mg/m/10 min without routine steroid premedication) or paclitaxel (225 mg/m/3 h with standard premedication) every 3 weeks. The primary end point was overall survival. RESULTS: A total of 400 patients were enrolled. Alopecia, arthralgias/myalgias, and cardiac events were significantly less frequent with PPX/carboplatin, whereas grade ≥3 neutropenia and grade 3 neuropathy showed a trend of worsening. There was no significant difference in the incidence of hypersensitivity reactions despite the absence of routine premedication in the PPX arm. Overall survival was similar between treatment arms (hazard ratio, 0.97; log rank p = 0.769). Median and 1-year survival rates were 7.9 months and 31%, for PPX versus 8 months and 31% for paclitaxel. Disease control rates were 64% and 69% for PPX and paclitaxel, respectively. Time to progression was similar: 3.9 months for PPX/carboplatin versus 4.6 months for paclitaxel/carboplatin (p = 0.210). CONCLUSION: PPX/carboplatin failed to provide superior survival compared with paclitaxel/carboplatin in the first-line treatment of PS 2 patients with NSCLC, but the results with respect to progression-free survival and overall survival were comparable and the PPX regimen was more convenient. © 2008International Association for the Study of Lung Cancer.
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Background: This open-label, randomised phase III study was designed to further investigate the clinical activity and safety of SRL172 (killed Mycobacterium vaccae suspension) with chemotherapy in the treatment of non-small-cell lung cancer (NSCLC). Patients and methods: Patients were randomised to receive platinum-based chemotherapy, consisting of up to six cycles of MVP (mitomycin, vinblastine and cisplatin or carboplatin) with (210 patients) or without (209 patients) monthly SRL172. Results: There was no statistical difference between the two groups in overall survival (primary efficacy end point) over the course of the study (median overall survival of 223 days versus 225 days; P = 0.65). However, a higher proportion of patients were alive at the end of the 15-week treatment phase in the chemotherapy plus SRL172 group (90%), than in the chemotherapy alone group (83%) (P = 0.061). At the end of the treatment phase, the response rate was 37% in the combined group and 33% in the chemotherapy alone group. Patients in the chemotherapy alone group had greater deterioration in their Global Health Status score (-14.3) than patients in the chemotherapy plus SRL172 group (-6.6) (P = 0.02). Conclusion: In this non-placebo controlled trial, SRL172 when added to standard cancer chemotherapy significantly improved patient quality of life without affecting overall survival times. © 2004 European Society for Medical Oncology.
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Recent welfare reform in Australia has been constructed around the now-familiar principle of paid work and willingness to work as the fundamental marker of social citizenship. Beginning with the long-term unemployed in Australia in the mid 1990s, the scope of welfare reform has now extended to include people with a disability – which is a category of income support that has been growing in Australia. From the national government’s point of view this growth is a financial concern as it seeks to move as many people as possible into paid work to support the costs of an ageing population (DEWR, 2005). In doing so, the government has changed the meaning of disability in terms of eligibility for financial support from the state, and at the same time redefined the role of people with a disability with regard to work, and the role of the state with regard to the disabled. This has been a matter of some political contention in Australia.
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This chapter profiles research that has explored the role of affect in the teaching of science in Australia particularly on primary or elementary science education. Affect is a complex set of characteristics that relate to the interactions between an individual’s knowledge and emotional responses to a stimulus. Thus, there are many dimensions and theoretical frameworks that inform our understanding of how and why people behave in particular ways.
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Australian multicultural society consists of culturally and linguistically diverse (CALD) migrants, refugees and international students from different parts of the world. Despite hardships, these individuals show resilience and adapt successfully. However, there is a dearth of scales measuring these positive developments and personal strengths. The study describes the development and evaluation of a scale measuring resilience and acculturation of CALD people. Items were generated for the Acculturation and Resilience Scale (AARS).The AARS and other acculturation and psychological distress scales were administered to 225 CALD community members. Exploratory factor analyses resulted in a 27-item AARS with three subscales: Acculturation, Resilience, and Spirituality. The three-factor structure was subjected to a confirmatory factor analysis on a sample of 515 international students. The factor structure stability was upheld by the second sample. The psychometric properties were investigated using the two samples and demonstrated satisfactory internal consistency, test-retest reliability, and divergent validity. The scale addresses a major gap in the literature and can be used to measure the positive acculturation and resilience of the newly arrived and relocated individuals. Further research is warranted to examine the scale’s psychometric properties with migrants and refugees from a range of ethnic communities.
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The Food and Nutrition stream of Australasian Child and Adolescent Obesity Research Network (ACAORN) aims to improve the quality of dietary methodologies and the reporting of dietary intake within Australasian child obesity research (http://www.acaorn.org.au/streams/nutrition/). With 2012 marking ACAORN’s 10th anniversary, this commentary profiles a selection of child obesity nutrition research published over the last decade by Food and Nutrition Stream members. In addition, stream activities have included the development of an online selection guide to assist researchers in their selection of appropriate dietary intake methodologies (http://www.acaorn.org.au/streams/nutrition/dietary-intake/index.php). The quantity and quality of research to guide effective child obesity prevention and treatment has increased substantially over the last decade. ACAORN provides a successful case study of how research networks can provide a collegial atmosphere to foster and co-ordinate research efforts in an otherwise competitive environment.
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Disproportionate representation of males and females in science courses and careers continues to be of concern. This article explores gender differences in Australian high school students’ perceptions of school science and their intentions to study university science courses. Nearly 3800 15-year-old students responded to a range of 5-point Likert items relating to intentions to study science at university, perceptions of career-related instrumental issues such as remuneration and job security, self-rated science ability and enjoyment of school science. Australian boys and girls reported enjoying science to a similar extent, however boys reported enjoying it more in relation to other subjects than did girls, and rated their ability in science compared to others in their class more highly than did girls. There was no significant difference between the mean responses of girls and boys to the item “It is likely I will choose a science-related university course when I leave school” and the strongest predictors of responses to this item were items relating to students’ liking for school science and awareness from school science of new and exciting jobs, followed by their perceived self-ability. These results are discussed in relation to socio-scientific values that interact with identity and career choices, employment prospects in science, and implications for science education.
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Background The majority of patients who attend emergency departments (EDs) in Saudi Arabia have non-urgent problems, resulting in overcrowding, excessive waiting times and delayed care for more acutely ill patients. The purpose of this research was to examine the reasons for non-urgent visits to a Saudi ED and factors associated with patient perceptions of urgency. Methods We administered a survey to 350 consecutively presenting Canadian Triage and Acuity Scale (CTAS) IV or V adult patients at a large tertiary ED in Riyadh region, Saudi Arabia, during 25 days of data collection in March 2013. Results Over half of the sample usually visited the ED to access healthcare. The most common reasons for attending the ED were not having a regular healthcare provider (63%), being able to receive care on the same day (62%), and the convenience of and access to medical care 24/7 (62%). Approximately two-thirds of CTAS V patients and one-third of CTAS IV patients believed their condition was more urgent than their triage nurse rating. Conclusion Multiple factors influence non-urgent visits to the ED in the Saudi context including insufficient community awareness of the role of the ED and perceived lack of access to primary healthcare services.
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Radical-directed dissociation of gas phase ions is emerging as a powerful and complementary alternative to traditional tandem mass spectrometric techniques for biomolecular structural analysis. Previous studies have identified that coupling of 2-[(2,2,6,6-tetramethylpiperidin-1-oxyl)methyl] benzoic acid (TEMPO-Bz) to the N-terminus of a peptide introduces a labile oxygen-carbon bond that can be selectively activated upon collisional activation to produce a radical ion. Here we demonstrate that structurally-defined peptide radical ions can also be generated upon UV laser photodissociation of the same TEMPO-Bz derivatives in a linear ion-trap mass spectrometer. When subjected to further mass spectrometric analyses, the radical ions formed by a single laser pulse undergo identical dissociations as those formed by collisional activation of the same precursor ion, and can thus be used to derive molecular structure. Mapping the initial radical formation process as a function of photon energy by photodissociation action spectroscopy reveals that photoproduct formation is selective but occurs only in modest yield across the wavelength range (300-220 nm), with the photoproduct yield maximised between 235 and 225 nm. Based on the analysis of a set of model compounds, structural modifications to the TEMPO-Bz derivative are suggested to optimise radical photoproduct yield. Future development of such probes offers the advantage of increased sensitivity and selectivity for radical-directed dissociation. © 2014 the Owner Societies.
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Breast cancer is the cancer that most commonly affects women worldwide. This type of cancer is genetically complex, but is strongly linked to steroid hormone signalling systems. Because microRNAs act as translational regulators of multiple genes, including the steroid nuclear receptors, single nucleotide polymorphisms (SNPs) in microRNAs genes can have potentially wide-ranging influences on breast cancer development. Thus, this study was conducted to investigate the relationships between six SNPs (rs6977848, rs199981120, rs185641358, rs113054794, rs66461782, and rs12940701) located in four miRNA genes predicted to target the estrogen receptor (miR-148a, miR-221, miR-186, and miR-152) and breast cancer risk in Caucasian Australian women. By using high resolution melt analysis (HRM) and polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP), 487 samples including 225 controls and 262 cases were genotyped. Analysis of their genotype and allele frequencies indicated that the differences between case and control populations was not significant for rs6977848, rs66461782, and rs12940701 because their p-values are 0.81, 0.93, 0.1 which are all above the threshold value (p=0.05). Our data thus suggests that these SNPs do not affect breast cancer risk in the tested population. In addition, rs199981120, rs185641358, and rs113054794 could not be found in this population, suggesting that these SNPs do not occur in Caucasian Australians.