984 resultados para C sequestration
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A nanostructured gold surface consisting of closely packed outwardly growing spikes is investigated for the electrochemical detection of dopamine and cytochrome c. A significant electrocatalytic effect for the electrooxidation of both dopamine and ascorbic acid at the nanostructured electrode was found due to the presence of surface active sites which allowed the detection of dopamine in the presence of excess ascorbic acid to be achieved by differential pulse voltammetry. By simple modification with a layer of Nafion, the enhanced electrocatalytic properties of the nanostructured surface was maintained while increasing the selectivity of dopamine detection in the presence of interfering species such as excess ascorbic and uric acids. Also, upon modification of the nanostructured surface with a monolayer of cysteine, the electrochemical response of immobilised cytochrome c in two distinct conformations was observed. This opens up the possibility of using such a nanostructured surface for the characterisation of other biomolecules and in bio-electroanalytical applications.
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Purpose To determine the rate of recurrence and associated risk factors following the use of mitomycin C (MMC) and/or interferon alpha-2b (IFN) for management of non-invasive ocular surface squamous neoplasia (OSSN). Design Retrospective non-comparative interventional case series. Methods Clinical practice setting of 135 patients treated consecutively with topical MMC (0.4 mg/mL) and/or IFN (1 million units/mL) for OSSN observed for clinical recurrence. Results Clinical recurrences were diagnosed in 19 of 135 (14.1%) eyes following topical treatment. The mean time to recurrence was 17.2 months (range 4 - 61) with 14 (73.7%) recurring within a two year period. There was no greater risk of recurrence identified for variables including lesion size, lesion location, gender, age, treatment type or duration. Post-hoc log-Rank pairwise comparisons revealed that lesions initially treated using surgery alone had significantly reduced time to recurrence (21.1 ± 5.6 months) compared to previous topical treatment with MMC (with or without surgery) (29.6 ± 4.7 months) (p = 0.04) and primary OSSN (23.2 ± 1.8 months) (p = 0.09). Conclusions Topical MMC and IFN are an effective treatment modality for a wide range of non-invasive OSSN. Topical therapy avoids the morbidity of excisional surgery with equivalent or reduced recurrence rates and should be considered as primary therapy.
Hepatitis C, mental health and equity of access to antiviral therapy : a systematic narrative review
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Introduction Access to hepatitis C (hereafter HCV) antiviral therapy has commonly excluded populations with mental health and substance use disorders because they were considered as having contraindications to treatment, particularly due to the neuropsychiatric effects of interferon that can occur in some patients. In this review we examined access to HCV interferon antiviral therapy by populations with mental health and substance use problems to identify the evidence and reasons for exclusion. Methods We searched the following major electronic databases for relevant articles: PsycINFO, Medline, CINAHL, Scopus, Google Scholar. The inclusion criteria comprised studies of adults aged 18 years and older, peer-reviewed articles, date range of (2002--2012) to include articles since the introduction of pegylated interferon with ribarvirin, and English language. The exclusion criteria included articles about HCV populations with medical co-morbidities, such as hepatitis B (hereafter HBV) and human immunodeficiency virus (hereafter HIV), because the clinical treatment, pathways and psychosocial morbidity differ from populations with only HCV. We identified 182 articles, and of these 13 met the eligibility criteria. Using an approach of systematic narrative review we identified major themes in the literature. Results Three main themes were identified including: (1) pre-treatment and preparation for antiviral therapy, (2) adherence and treatment completion, and (3) clinical outcomes. Each of these themes was critically discussed in terms of access by patients with mental health and substance use co-morbidities demonstrating that current research evidence clearly demonstrates that people with HCV, mental health and substance use co-morbidities have similar clinical outcomes to those without these co-morbidities. Conclusions While research evidence is largely supportive of increased access to interferon by people with HCV, mental health and substance use co-morbidities, there is substantial further work required to translate evidence into clinical practice. Further to this, we conclude that a reconsideration of the appropriateness of the tertiary health service model of care for interferon management is required and exploration of the potential for increased HCV care in primary health care settings.
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Background: Phase III studies suggest that non-small-cell lung cancer (NSCLC) patients treated with cisplatin-docetaxel may have higher response rates and better survival compared with other platinum-based regimens. We report the final results of a randomised phase III study of docetaxel and carboplatin versus MIC or MVP in patients with advanced NSCLC. Patients and methods: Patients with biopsy proven stage III-IV NSCLC not suitable for curative surgery or radiotherapy were randomised to receive four cycles of either DCb (docetaxel 75 mg/m 2, carboplatin AUC 6), or MIC/MVP (mitomycin 6 mg/m 2, ifosfamide 3 g/m 2 and cisplatin 50 mg/m 2 or mitomycin 6 mg/ m 2, vinblastine 6 mg/m 2 and cisplatin 50 mg/m 2, respectively), 3 weekly. The primary end point was survival, secondary end points included response rates, toxicity and quality of life. Results: The median follow-up was 17.4 months. Overall response rate was 32% for both arms (partial response = 31%, complete response = 1%); 32% of MIC/MVP and 26% of DCb patients had stable disease. One-year survival was 39% and 35% for DCb and MIC/MVP, respectively. Two-year survival was 13% with both arms. Grade 3/4 neutropenia (74% versus 43%, P < 0.005), infection (18% versus 9%, P = 0.01) and mucositis (5% versus 1%, P = 0.02) were more common with DCb than MIC/MVP. The MIC/MVP arm had significant worsening in overall EORTC score and global health status whereas the DCb arm showed no significant change. Conclusions: The combination of DCb had similar efficacy to MIC/MVP but quality of life was better maintained. © 2006 European Society for Medical Oncology.
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Background: Mitomycin C and etoposide have both demonstrated activity against gastric carcinoma. Etoposide is a topoisomerase II inhibitor with evidence for phase-specific and schedule-dependent activity. Patients and method. Twenty-eight consecutive patients with advanced upper gastrointestinal adenocarcinoma were treated with intravenous (i.v.) bolus mitomycin C 6 mg/m2 on day 1 every 21 days to a maximum of four courses. Oral etoposide capsules 50 mg b.i.d. (or 35 mg b.i.d. liquid) were administered days 1 to 10 extending to 14 days in subsequent courses if absolute neutrophil count >1.5 x 109/l on day 14 of first course, for up to six courses. Results: Twenty-six patients were assessed for response of whom 12 had measurable disease and 14 evaluable disease. Four patients had a documented response (one complete remission, three partial remissions) with an objective response rate of 15% (95% confidence interval (95% CI) 4%-35%). Eight patients had stable disease and 14 progressive disease. The median survival was six months. The schedule was well tolerated with no treatment-related deaths. Nine patients experienced leucopenia (seven grade II and two grade III). Nausea and vomiting (eight grade II, one grade III), fatigue (eight grade II, two grade III) and anaemia (seven grade II, two grade III) were the predominant toxicities. Conclusion: This out-patient schedule is well tolerated and shows modest activity in the treatment of advanced upper gastrointestinal adenocarcinoma. Further studies using protracted schedules of etoposide both orally and as infusional treatment should be developed.
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Tumour angiogenesis has been recently recognised as one of the most important prognostic factors in lung cancer. Although a variety of angiogenic factors have been identified, the angiogenesis process remains poorly understood. Bcl-2, c-erbB-2 and p53 are well-known oncogenes involved in non- small-cell lung cancer pathogenesis. A direct correlation of thymidine phosphorylase (TP) and of vascular endothelial growth factor (VEGF) with intratumoural angiogenesis has been reported. In the present study we investigated the possible regulatory role if bcl-2, c-erB-2 proteins in angiogenesis and in VEGF and TP expression in non-small-cell lung cancer. Two hundred sixteen specimens from T1,2-NO, 1 staged patients treated with surgery alone were immunohistochemically examined. Bcl-2 and c-erbB-2 were significantly inversely related to each other (P = 0.04) and both were inversely associated with microvessel density (P < 0.02). High TP and VEGF reactivity was statistically related to loss of bcl-2 expression (P < 0.01). A significant co-expression of c-erbB-2 with TP was noted (P = 0.01). However, TP expression was related to high angiogenesis only in cases with absence of c-erB-2 expression (P < 0.0001). c-erbB-2 expression in poorly vascularised tumours was linked with poor outcome (P = 0.03). The present study provides strong evidence that the bcl-2 gene has a suppressive function over genes involved in both angiogenesis (VEGF and TP) and cell migration (c- erbB-2) in NSCLC. TP and c-erbB-2 proteins are significantly, and often simultaneously, expressed in bcl-2 negative cases. However, expression of the c-erbB-2 abolishes the TP-related angiogenic activity. Whether this is a result of a direct activity of the c-erbB-2 protein or a consequence of a c- erbB-2-related immune response remains to be further investigated.
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Drosophila possesses the core gene silencing machinery but, like all insects, lacks the canonical RNA-dependent RNA polymerases (RdRps) that in C. elegans either trigger or enhance two major small RNA-dependent gene silencing pathways. Introduction of two different nematode RdRps into Drosophila showed them to be functional, resulting in differing silencing activities. While RRF-1 enhanced transitive dsRNA-dependent silencing, EGO-1 triggered dsRNA-independent silencing, specifically of transgenes. The strain w; da-Gal4; UAST-ego-1, constitutively expressing ego-1, is capable of silencing transgene including dsRNA hairpin upon a single cross, which created a powerful tool for research in Drosophila. In C. elegans, EGO-1 is involved in transcriptional gene silencing (TGS) of chromosome regions that are unpaired during meiosis. There was no opportunity for meiotic interactions involving EGO-1 in Drosophila that would explain the observed transgene silencing. Transgene DNA is, however, unpaired during the pairing of chromosomes in embryonic mitosis that is an unusual characteristic of Diptera, suggesting that in Drosophila, EGO-1 triggers transcriptional silencing of unpaired DNA during embryonic mitosis. © 2012 Springer Basel.
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Successful control of sexually transmitted diseases (STDs) through vaccination will require the development of vaccine strategies that target protective immunity to both the female and male reproductive tracts (MRT). In the male, the immune privileged nature of the male reproductive tract provides a barrier to entry of serum immunoglobulins into the male reproductive ducts, thereby preventing the induction of protective immunity using conventional injectable vaccination techniques. In this study we investigated the potential of intranasal (IN) immunization to elicit anti-chlamydial immunity in BALB/c male mice. Intranasal immunization with Chlamydia muridarum major outer membrane protein (MOMP) admixed with cholera toxin (CT) resulted in high levels of MOMP-specific IgA in prostatic fluids (PF) and MOMP-specific IgA-secreting cells in the prostate. Prostatic fluid IgA inhibited in vitro infection of McCoy cells with C. muridarum. Using RT-PCR we also show that mRNA for the polymeric immunoglobulin receptor (PIgR), which transports IgA across mucosal epithelia, is expressed only in the prostate but not in other regions of the male reproductive ducts upstream of the prostate. These data suggest that using intranasal immunization to target IgA to the prostate may protect males against STDs while at the same time maintaining the state of immune privilege within the MRT.
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This book is one in a series of seven atlases covering the ophthalmic sub-specialties: cornea, retina, glaucoma, oculoplastics, neuro-ophthalmology, uveitis and paediatrics. The author of Cornea and editor of the series is Christopher Rapuano, Attending Surgeon and Director of the Cornea Service at Wills Eye Hospital in Philadelphia, Pennsylvania, USA. In the introduction to the book, Rapuano states ‘The goal of this series is to provide an up-to-date clinical overview of the major areas of ophthalmology for students, residents and practitioners in all the healthcare professions’...
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X-ray diffraction structure functions for water flowing in a 1.5 mm diameter siphon in the temperature range 4 – 63 °C were obtained using a 20 keV beam at the Australian Synchrotron. These functions were compared with structure functions obtained at the Advanced Light Source for a 0.5 mm thick sample of water in the temperature range 1 – 77 °C irradiated with an 11 keV beam. The two sets of structure functions are similar, but there are subtle differences in the shape and relative position of the two functions suggesting a possible differences between the structure of bulk and siphon water. In addition, the first structural peak (Q0) for water in a siphon, showed evidence of a step-wise increase in Q0 with increasing temperature rather than a smoothly varying increase. More experiments are required to investigate this apparent difference.
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Learning programming is known to be difficult. One possible reason why students fail programming is related to the fact that traditional learning in the classroom places more emphasis on lecturing the material instead of applying the material to a real application. For some students, this teaching model may not catch their interest. As a result they may not give their best effort to understand the material given. Seeing how the knowledge can be applied to real life problems can increase student interest in learning. As a consequence, this will increase their effort to learn. Anchored learning that applies knowledge to solve real life problems may be the key to improving student performance. In anchored learning, it is necessary to provide resources that can be accessed by the student as they learn. These resources can be provided by creating an Intelligent Tutoring System (ITS) that can support the student when they need help or experience a problem. Unfortunately, there is no ITS developed for the programming domain that has incorporated anchored learning in its teaching system. Having an ITS that supports anchored learning will not only be able to help the student learn programming effectively but will also make the learning process more enjoyable. This research tries to help students learn C# programming using an anchored learning ITS named CSTutor. Role playing is used in CSTutor to present a real world situation where they develop their skills. A knowledge base using First Order Logic is used to represent the student's code and to give feedback and assistance accordingly.
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This article investigates the discourses of academic legitimacy that surround the production, consumption, and accreditation of online scholarship. Using the web-based media and cultural studies journal (http://journal.media-culture.org.au) as a case study, it examines how online scholarly journals often position themselves as occupying a space between the academic and the popular and as having a functional advantage over print-based media in promoting a spirit of public intellectualism. The current research agenda of both government and academe prioritises academic research that is efficient, self-promoting, and relevant to the public. Yet, although the cost-effectiveness and public-intellectual focus of online scholarship speak to these research priorities, online journals such as M/C Journal have occupied, and continue to occupy, an unstable position in relation to the perceived academic legitimacy of their content. Although some online scholarly journals have achieved a limited form of recognition within a system of accreditation that still privileges print-based scholarship, I argue that this, nevertheless, points to the fact that traditional textual notions of legitimate academic work continue to pervade the research agenda of an academe that increasingly promotes flexible delivery of teaching and online research initiatives.
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In this paper, an integrated inter-vehicles wireless communications and positioning system supporting alternate positioning techniques is proposed to meet the requirements of safety applications of Cooperative Intelligent Transportation Systems (C-ITS). Recent advances have repeatedly demonstrated that road safety problems can be to a large extent addressed via a range of technologies including wireless communications and positioning in vehicular environments. The novel communication stack utilizing a dedicated frequency spectrum (e.g. at 5.9 GHz band), known as Dedicated Short-Range Communications (DSRC), has been particularly designed for Wireless Access in Vehicular Environments (WAVE) to support safety applications in highly dynamic environments. Global Navigation Satellite Systems (GNSS) is another essential enabler to support safety on rail and roads. Although current vehicle navigation systems such as single frequency Global Positioning System (GPS) receivers can provide route guidance with 5-10 meters (road-level) position accuracy, positioning systems utilized in C-ITS must provide position solutions with lane-level and even in-lane-level accuracies based on the requirements of safety applications. This article reviews the issues and technical approaches that are involved in designing a vehicular safety communications and positioning architecture; it also provides technological solutions to further improve vehicular safety by integrating the DSRC and GNSS-based positioning technologies.