19 resultados para Nicotine - Theses

em QUB Research Portal - Research Directory and Institutional Repository for Queen's University Belfast


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Rapid, quantitative SERS analysis of nicotine at ppm/ppb levels has been carried out using stable and inexpensive polymer-encapsulated Ag nanoparticles (gel-colls). The strongest nicotine band (1030 cm(-1)) was measured against d(5)-pyridine internal standard (974 cm(-1)) which was introduced during preparation of the stock gel-colls. Calibration plots of I-nic/I-pyr against the concentration of nicotine were non-linear but plotting I-nic/I-pyr against [nicotine](x) (x = 0.6-0.75, depending on the exact experimental conditions) gave linear calibrations over the range (0.1-10 ppm) with R-2 typically ca. 0.998. The RMS prediction error was found to be 0.10 ppm when the gel-colls were used for quantitative determination of unknown nicotine samples in 1-5 ppm level. The main advantages of the method are that the gel-colls constitute a highly stable and reproducible SERS medium that allows high throughput (50 sample h(-1)) measurements.

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Background:Changes in the immune and inflammatory response are induced by smoking tobacco but underlying mechanisms remain to be elucidated.

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Background: Cigarette smoke induces a pro-inflammatory response in airway epithelial cells but it is not clear which of the various chemicals contained within cigarette smoke (CS) should be regarded as predominantly responsible for these effects. We hypothesised that acrolein, nicotine and acetylaldehyde, important chemicals contained within volatile cigarette smoke in terms of inducing inflammation and causing addiction, have immunomodulatory effects in primary nasal epithelial cell cultures (PNECs).

Methods: PNECs from 19 healthy subjects were grown in submerged cultures and were incubated with acrolein, nicotine or acetylaldehyde prior to stimulation with Pseudomonas aeruginosa lipopolysaccharide (PA LPS). Experiments were repeated using cigarette smoke extract (CSE) for comparison. IL-8 was measured by ELISA, activation of NF-κB by ELISA and Western blotting, and caspase-3 activity by Western blotting. Apoptosis was evaluated using Annexin-V staining and the terminal transferase-mediated dUTP nick end-labeling (TUNEL) method.

Results: CSE was pro-inflammatory after a 24 h exposure and 42% of cells were apoptotic or necrotic after this exposure time. Acrolein was pro-inflammatory for the PNEC cultures (30 μM exposure for 4 h inducing a 2.0 fold increase in IL-8 release) and also increased IL-8 release after stimulation with PA LPS. In contrast, nicotine had anti-inflammatory properties (0.6 fold IL-8 release after 50 μM exposure to nicotine for 24 h), and acetylaldehyde was without effect. Acrolein and nicotine had cellular stimulatory and anti-inflammatory effects respectively, as determined by NF-κB activation. Both chemicals increased levels of cleaved caspase 3 and induced cell death.

Conclusions: Acrolein is pro-inflammatory and nicotine anti-inflammatory in PNEC cultures. CSE induces cell death predominantly by apoptotic mechanisms. 

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This paper is an examination of evidential holism, a prominent position in epistemology and the philosophy of science which claims that experiments only ever confirm or refute entire theories. The position is historically associated with W.V. Quine, and it is at once both popular and notorious, as well as being largely under-described. But even though there’s no univocal statement of what holism is or what it does, philosophers have nevertheless made substantial assumptions about its content and its truth. Moreover they have drawn controversial and important conclusions from these assumptions. In this paper I distinguish three types of evidential holism and argue that the most oft-cited and controversial thesis is entirely unmotivated. The other two theses are much overlooked, but are well-motivated and free from controversial implications.

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Background
Restorative justice is “a process whereby parties with a stake in a specific offence resolve collectively how to deal with the aftermath of the offence and its implications for the future” (Marshall 2003). Despite the increasing use of restorative justice programmes as an alternative to court proceedings, no systematic review has been undertaken of the available evidence on the effectiveness of these programmes with young offenders. Recidivism in young offenders is a particularly worrying problem, as recent surveys have indicated
the frequency of re-offences for young offenders has ranged from 40.2% in 2000 to 37.8% in 2007 (Ministry of Justice 2009)

Objectives
To evaluate the effects of restorative justice conferencing programmes for reducing recidivism in young offenders.

Search methods
We searched the following databases up to May 2012: CENTRAL, 2012 Issue 5, MEDLINE (1978 to current), Bibliography of Nordic Criminology (1999 to current), Index to Theses (1716 to current), PsycINFO (1887 to current), Social Sciences Citation Index (1970 to current), Sociological Abstracts (1952 to current), Social Care Online (1985 to current), Restorative Justice Online (1975 to current), Scopus (1823 to current), Science Direct (1823 to current), LILACS (1982 to current), ERIC (1966 to current), Restorative Justice Online (4May 2012),WorldCat (9May 2012), ClinicalTrials.gov (19May 2012) and ICTRP (19May 2012). ASSIA,National Criminal Justice Reference Service and Social Services Abstracts were searched up to May 2011. Relevant bibliographies, conference programmes and journals were also searched.

Selection criteria
Randomised controlled trials (RCTs) or quasi-RCTs of restorative justice conferencing versus management as usual, in young offenders.

Data collection and analysis
Two authors independently assessed the risk of bias of included trials and extracted the data. Where necessary, original investigators were contacted to obtain missing information.

Main results
Four trials including a total of 1447 young offenders were included in the review. Results failed to find a significant effect for restorative justice conferencing over normal court procedures for any of the main analyses, including number re-arrested (odds ratio (OR) 1.00, 95% confidence interval (CI) 0.59 to 1.71; P = 0.99), monthly rate of reoffending (standardised mean difference (SMD) -0.06, 95% CI -0.28 to 0.16; P = 0.61), young person’s remorse following conference (OR 1.73, 95% CI 0.97 to 3.10; P = 0.06), young person’s recognition of wrongdoing following conference (OR 1.97, 95% CI 0.81 to 4.80; P = 0.14), young person’s self-perception following conference (OR 0.95, 95% CI 0.55 to 1.63; P = 0.85), young person’s satisfaction following conference (OR 0.42, 95% CI 0.04 to 4.07; P = 0.45) and victim’s satisfaction following conference (OR 4.05, 95%CI 0.56 to 29.04; P = 0.16). A small number of sensitivity analyses did indicate significant effects, although all are to be interpreted with caution.

Authors’ conclusions
There is currently a lack of high quality evidence regarding the effectiveness of restorative justice conferencing for young offenders. Caution is urged in interpreting the results of this review considering the small number of included studies, subsequent low power and high risk of bias. The effects may potentially be more evident for victims than offenders. The need for further research in this area is highlighted.

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The term `laser cooling' is applied to the use of optical means to cool the motional energies of either atoms and molecules, or micromirrors. In the literature, these two strands are kept largely separate; both, however suffer from severe limitations. Laser cooling of atoms and molecules largely relies on the internal level structure of the species being cooled. As a result, only a small number of elements and a tiny number of molecules can be cooled this way. In the case of micromirrors, the problem lies in the engineering of micromirrors that need to satisfy a large number of constraints---these include a high mechanical Q-factor, high reflectivity and very good optical quality, weak coupling to the substrate, etc.---in order to enable efficient cooling. During the course of this thesis, I will draw these two sides of laser cooling closer together by means of a single, generically applicable scattering theory that can be used to explain the interaction between light and matter at a very general level. I use this `transfer matrix' formalism to explore the use of the retarded dipole--dipole interaction as a means of both enhancing the efficiency of micromirror cooling systems and rendering the laser cooling of atoms and molecules less species selective. In particular, I identify the `external cavity cooling' mechanism, whereby the use of an optical memory in the form of a resonant element (such as a cavity), outside which the object to be cooled sits, can potentially lead to the construction of fully integrated optomechanical systems and even two-dimensional arrays of translationally cold atoms, molecules or even micromirrors.

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Aim: To undertake a systematic review of the literature on the effect of environmental tobacco smoke (ETS) and eye disease. Methods: Medline (1950-January Week 2 2007), EMBASE (1980 to 2007 Week 07), SCOPUS and Science Direct were searched on ETS exposure and eye disease using various combinations of the following terms: passive smoking, environmental tobacco smoke, sidestream smoke, involuntary smoking, secondhand smoke; with eye, conjunctiva, sclera, episclera, cornea, lens, iris, retina, choroid, uvea, optic nerve, uveitis, iritis, blindness, visual loss, cataract, thyroid eye disease, conjunctivitis, age-related macular degeneration, dry eye, tears. The above terms were also used to search abstracts published on The Association for Research in Vision and Ophthalmology Annual Meeting abstracts, from 1995 to 2006, and the grey literature, including PhD and MSc theses/dissertations. A search was further conducted specifically on eye diseases where active smoking has been proposed to be a risk factor, including age-related macular degeneration, Graves ophthalmology, glaucoma, uveitis, refractive errors, strabismus, tobacco-alcohol amblyopia, non-arteritic ischaemic optic neuropathy, Leber optic neuropathy and diabetic retinopathy. Given the scarce number of studies found through the above search, all articles found on ETS and eye disease were included in this review. Results: Seven studies evaluated the possible relationship between ETS and an eye disease. These studies referred to refractive errors in children (n = 2), cataract (n = 1), age-related macular degeneration (n = 3) and Grave ophthalmopathy (n = 1). The data available were insufficient to establish conclusive relationships between ETS and these eye diseases. Conclusion: Very scarce data exist in the literature on the effect of ETS on diseases of the eye. It seems appropriate that ETS should be included in future studies addressing the effect of smoking on eye disease.

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Early-onset child conduct problems are common and costly. A large number of studies and some previous reviews have focused on behavioural and cognitive-behavioural group-based parenting interventions, but methodological limitations are commonplace and evidence for the effectiveness and cost-effectiveness of these programmes has been unclear. To assess the effectiveness and cost-effectiveness of behavioural and cognitive-behavioural group-based parenting programmes for improving child conduct problems, parental mental health and parenting skills. We searched the following databases between 23 and 31 January 2011: CENTRAL (2011, Issue 1), MEDLINE (1950 to current), EMBASE (1980 to current), CINAHL (1982 to current), PsycINFO (1872 to current), Social Science Citation Index (1956 to current), ASSIA (1987 to current), ERIC (1966 to current), Sociological Abstracts (1963 to current), Academic Search Premier (1970 to current), Econlit (1969 to current), PEDE (1980 to current), Dissertations and Theses Abstracts (1980 to present), NHS EED (searched 31 January 2011), HEED (searched 31 January 2011), DARE (searched 31 January 2011), HTA (searched 31 January 2011), mRCT (searched 29 January 2011). We searched the following parent training websites on 31 January 2011: Triple P Library, Incredible Years Library and Parent Management Training. We also searched the reference lists of studies and reviews. We included studies if: (1) they involved randomised controlled trials (RCTs) or quasi-randomised controlled trials of behavioural and cognitive-behavioural group-based parenting interventions for parents of children aged 3 to 12 years with conduct problems, and (2) incorporated an intervention group versus a waiting list, no treatment or standard treatment control group. We only included studies that used at least one standardised instrument to measure child conduct problems. Two authors independently assessed the risk of bias in the trials and the methodological quality of health economic studies. Two authors also independently extracted data. We contacted study authors for additional information. This review includes 13 trials (10 RCTs and three quasi-randomised trials), as well as two economic evaluations based on two of the trials. Overall, there were 1078 participants (646 in the intervention group; 432 in the control group). The results indicate that parent training produced a statistically significant reduction in child conduct problems, whether assessed by parents (standardised mean difference (SMD) -0.53; 95% confidence interval (CI) -0.72 to -0.34) or independently assessed (SMD -0.44; 95% CI -0.77 to -0.11). The intervention led to statistically significant improvements in parental mental health (SMD -0.36; 95% CI -0.52 to -0.20) and positive parenting skills, based on both parent reports (SMD -0.53; 95% CI -0.90 to -0.16) and independent reports (SMD -0.47; 95% CI -0.65 to -0.29). Parent training also produced a statistically significant reduction in negative or harsh parenting practices according to both parent reports (SMD -0.77; 95% CI -0.96 to -0.59) and independent assessments (SMD -0.42; 95% CI -0.67 to -0.16). Moreover, the intervention demonstrated evidence of cost-effectiveness. When compared to a waiting list control group, there was a cost of approximately $2500 (GBP 1712; EUR 2217) per family to bring the average child with clinical levels of conduct problems into the non-clinical range. These costs of programme delivery are modest when compared with the long-term health, social, educational and legal costs associated with childhood conduct problems. Behavioural and cognitive-behavioural group-based parenting interventions are effective and cost-effective for improving child conduct problems, parental mental health and parenting skills in the short term. The cost of programme delivery was modest when compared with the long-term health, social, educational and legal costs associated with childhood conduct problems. Further research is needed on the long-term assessment of outcomes.

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The advent of next generation sequencing technologies (NGS) has expanded the area of genomic research, offering high coverage and increased sensitivity over older microarray platforms. Although the current cost of next generation sequencing is still exceeding that of microarray approaches, the rapid advances in NGS will likely make it the platform of choice for future research in differential gene expression. Connectivity mapping is a procedure for examining the connections among diseases, genes and drugs by differential gene expression initially based on microarray technology, with which a large collection of compound-induced reference gene expression profiles have been accumulated. In this work, we aim to test the feasibility of incorporating NGS RNA-Seq data into the current connectivity mapping framework by utilizing the microarray based reference profiles and the construction of a differentially expressed gene signature from a NGS dataset. This would allow for the establishment of connections between the NGS gene signature and those microarray reference profiles, alleviating the associated incurring cost of re-creating drug profiles with NGS technology. We examined the connectivity mapping approach on a publicly available NGS dataset with androgen stimulation of LNCaP cells in order to extract candidate compounds that could inhibit the proliferative phenotype of LNCaP cells and to elucidate their potential in a laboratory setting. In addition, we also analyzed an independent microarray dataset of similar experimental settings. We found a high level of concordance between the top compounds identified using the gene signatures from the two datasets. The nicotine derivative cotinine was returned as the top candidate among the overlapping compounds with potential to suppress this proliferative phenotype. Subsequent lab experiments validated this connectivity mapping hit, showing that cotinine inhibits cell proliferation in an androgen dependent manner. Thus the results in this study suggest a promising prospect of integrating NGS data with connectivity mapping. © 2013 McArt et al.

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No bioadhesive patch-based system is currently marketed. This is despite an extensive number of literature reports on such systems detailing their advantages over conventional pressure sensitive adhesive-based patches in wet environments and describing successful delivery of a diverse array of drug substances. This lack of proprietary bioadhesive patches is largely due to the fact that such systems are exclusively water-based, meaning drying is difficult. In this paper we describe, for the first time, a novel multiple lamination method for production of bioadhesive patches. In contrast to patches produced using a conventional casting approach, which took 48 hours to dry, bioadhesive films prepared using the novel multiple lamination method were dried in 15?min and were folded into formed patches in a further 10?min. Patches prepared by both methods had comparable physicochemical properties. The multiple lamination method allowed supersaturation of 5-aminolevulinic acid to be achieved in formed patch matrices. However, drug release studies were unable to show an advantage for supersaturation with this particular drug, due to its water high solubility. The multiple lamination method allowed greater than 90% of incorporated nicotine to remain within formed patches, in contrast to the 48% achieved for patches prepared using a conventional casting approach. The procedure described here could readily be adapted for automation by industry. Due to the reduced time, energy and ensuing finance now required, this could lead to bioadhesive patch-based drug delivery systems becoming commercially viable. This would, in turn, mean that pathological conditions occurring in wet or moist areas of the body could now be routinely treated by prolonged site-specific drug delivery, as mediated by a commercially produced bioadhesive patch.

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Educational gaming in the health sciences: systematic review. Aim. This paper is a report of a review to investigate the use of games to support classroom learning in the health sciences. Background. One aim of education in the health sciences is to enable learners to develop professional competence. Students have a range of learning styles and innovative teaching strategies assist in creating a dynamic learning environment. New attitudes towards experiential learning methods have contributed to the expansion of gaming as a strategy. Data sources. A search for studies published between January 1980 and June 2008 was undertaken, using appropriate search terms. The databases searched were: British Education Index, British Nursing Index, The Cochrane Library, CINAHLPlus, Medline, PubMed, ERIC, PsychInfo and Australian Education Index. Methods. All publications and theses identified through the search were assessed for relevance. Sixteen papers reporting empirical studies or reviews that involved comparison of gaming with didactic methods were included. Results. The limited research available indicates that, while both traditional didactic methods and gaming have been successful in increasing student knowledge, neither method is clearly more helpful to students. The use of games generally enhances student enjoyment and may improve long-term retention of information. Conclusion. While the use of games can be viewed as a viable teaching strategy, care should be exercised in the use of specific games that have not been assessed objectively. Further research on the use of gaming is needed to enable educators to gaming techniques appropriately for the benefit of students and, ultimately, patients.