196 resultados para drug selectivity

em Queensland University of Technology - ePrints Archive


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Endothelin-1 (ET-1) is a potent vasoactive peptide and a hypoxia-inducible angiogenic growth factor associated with the development and growth of solid tumours. This study evaluated the expression of big endothelin-1 (big ET-1), a stable precursor of ET-1, and ET-1 in non-small cell lung cancer (NSCLC). Big ET-1 expression was evaluated in paraffin-embedded tissue sections from 10 NSCLC tumours using immunohistochemistry and in situ hybridisation. The production of big ET-1 and ET-1 was studied in six established NSCLC cell lines. The plasma concentrations of big ET-1 were measured in 30 patients with proven NSCLC prior to chemotherapy by means of a sandwich enzyme-linked immunoassay and compared to levels in 20 normal controls. Big ET-1 immunostaining was detected in the cancer cells of all tumours studied. Using in situ hybridisation, tumour cell big ET-1 mRNA expression was demonstrated in all samples. All six NSCLC cell lines expressed ET-1, with big ET-1 being detected in three. The median big ET-1 plasma level in patients with NSCLC was 5.4 pg/mL (range 0-22.7 pg/mL) and was significantly elevated compared to median big ET-1 plasma levels in controls, 2.1 pg/mL (1.2-13.4 pg/mL) (p=0.0001). Furthermore, patients with plasma big ET-1 levels above the normal range (upper tertile) had a worse outcome (p=0.01). In conclusion, big ET-1/ET-1 is expressed by resected NSCLC specimens and tumour cell lines. Plasma big ET-1 levels are elevated in NSCLC patients compared to controls with levels >7.8 pg/mL being associated with a worse outcome. The development of selective ET-1 antagonists such as Atrasentan indicates that ET-1 may be a therapeutic target in NSCLC. © 2004 Wichtig Editore.

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Antioestrogens are among the most widely used agents in the treatment of breast cancer. There has been a recent surge of interest in these compounds because of their potential breast cancer chemopreventive properties. The newer generation of antioestrogens, with increased selectivity and better toxicity profiles, have the potential to increase the effectiveness of hormonal treatment of breast cancer. The selective oestrogen receptor modulators (SERMs) hold the promise of revolutionising the care of healthy postmenopausal women with their beneficial effects on bone and lipids in addition to the chemoprevention of breast cancer.

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Police services in a number of Australian states and overseas jurisdictions have begun to implement or consider random road-side drug testing of drivers. This paper outlines research conducted to provide an estimate of the extent of drug driving in a sample of Queensland drivers in regional, rural and metropolitan areas. Oral fluid samples were collected from 2657 Queensland motorists and screened for illicit substances including cannabis (delta 9 tetrahydrocannibinol [THC]), amphetamines, ecstasy, and cocaine. Overall, 3.8% of the sample (n = 101) screened positive for at least one illicit substance, although multiple drugs were identified in a sample of 23 respondents. The most common drugs detected in oral fluid were ecstasy (n = 53), and cannabis (n = 46) followed by amphetamines (n = 23). A key finding was that cannabis was confirmed as the most common self-reported drug combined with driving and that individuals who tested positive to any drug through oral fluid analysis were also more likely to report the highest frequency of drug driving. Furthermore, a comparison between drug vs. drink driving detection rates for one region of the study, revealed a higher detection rate for drug driving (3.8%) vs. drink driving (0.8%). This research provides evidence that drug driving is relatively prevalent on Queensland roads, and may in fact be more common than drink driving. This paper will further outline the study findings’ and present possible directions for future drug driving research.

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Single nucleotide polymorphisms (SNPs) are unique genetic differences between individuals that contribute in significant ways to the determination of human variation including physical characteristics like height and appearance as well as less obvious traits such as personality, behaviour and disease susceptibility. SNPs can also significantly influence responses to pharmacotherapy and whether drugs will produce adverse reactions. The development of new drugs can be made far cheaper and more rapid by selecting participants in drug trials based on their genetically determined response to drugs. Technology that can rapidly and inexpensively genotype thousands of samples for thousands of SNPs at a time is therefore in high demand. With the completion of the human genome project, about 12 million true SNPs have been identified to date. However, most have not yet been associated with disease susceptibility or drug response. Testing for the appropriate drug response SNPs in a patient requiring treatment would enable individualised therapy with the right drug and dose administered correctly the first time. Many pharmaceutical companies are also interested in identifying SNPs associated with polygenic traits so novel therapeutic targets can be discovered. This review focuses on technologies that can be used for genotyping known SNPs as well as for the discovery of novel SNPs associated with drug response.

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Typically adolescents' friends are considered a risk factor for adolescent engagement in risk-taking. This study took a more novel approach, by examining adolescent friendship as a protective factor. In particular it investigated friends' potential to intervene to reduce risk-taking. 540 adolescents (mean age 13.47 years) were asked about their intention to intervene to reduce friends' alcohol, drug and alcohol-related harms and about psychosocial factors potentially associated with intervening. More than half indicated that they would intervene in friends' alcohol, drug use, alcohol-related harms and interpersonal violence. Intervening was associated with being female, having friends engage in overall less risk-taking and having greater school connectedness. The findings provide an important understanding of increasing adolescent protective behavior as a potential strategy to reduce alcohol and drug related harms.

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The crystal structure of the hydrated proton-transfer compound of the drug quinacrine [rac-N'-(6-chloro-2-methoxyacridin-9-yl)-N,N-diethylpentane-1,4-diamine] with 4,5-dichlorophthalic acid, C23H32ClN3O2+ . 2(C8H3Cl2O4-).4H2O (I), has been determined at 200 K. The four labile water molecules of solvation form discrete ...O--H...O--H... hydrogen-bonded chains parallel to the quinacrine side chain, the two N--H groups of which act as hydrogen-bond donors for two of the water acceptor molecules. The other water molecules, as well as the acridinium H atom, also form hydrogen bonds with the two anion species and extend the structure into two-dimensional sheets. Between these sheets there are also weak cation--anion and anion--anion pi-pi aromatic ring interactions. This structure represents only the third example of a simple quinacrine derivative for which structural data are available but differs from the other two in that it is unstable in the X-ray beam due to efflorescence, probably associated with the destruction of the unusual four-membered water chain structures.

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Introduction and Aims: Since the 1990s illicit drug use death rates in Australia have increased markedly. There is a notable gap in knowledge about changing socio-economic inequalities in drug use death rates. Some limited Australian and overseas data point to higher rates of drug death in the lowest socio-economic groups, but the paucity of available studies and their sometimes conflicting findings need to be addressed. Design and Methods: This paper uses data obtained from the Australian Bureau of Statistics (ABS) to examine changes in age-standardised drug-induced mortality rates for Australian males over the period 1981 – 2002. Socio-economic status was categorised as manual or non-manual work status. Results: With the rapid increase in drug-induced mortality rates in the 1990s, there was a parallel increase in socio-economic inequalities in drug-induced deaths. The decline in drug death rates from 2000 onwards was associated with a decline in socio-economic inequalities. By 2002, manual workers had drug death rates well over twice the rate of non-manual workers. Discussion: Three factors are identified which contribute to these socio-economic inequalities in mortality. First, there has been an age shift in deaths evident only for manual workers. Secondly, there has been an increase in availability until 1999 and a relative decline in the cost of the drug, which most often leads to drug death (heroin). Thirdly, there has been a shift to amphetamine use which may lead to significant levels of morbidity, but few deaths. [Najman JM, Toloo G, Williams GM. Increasing socio-economic inequalities in drug-induced deaths in Australia: 1981–2002.

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In December 2007, random roadside drug testing commenced in Queensland, Australia. Subsequently, the aim of this study was to explore the preliminary impact of Queensland’s drug driving legislation and enforcement techniques by applying Stafford and Warr’s [Stafford, M. C., & Warr, M. (1993). A reconceptualization of general and specific deterrence. Journal of Research in Crime and Delinquency, 30, 123-135] reconceptualization of deterrence theory. Completing a comprehensive drug driving questionnaire were 899 members of the public, university students, and individuals referred to a drug diversion program. Of note was that approximately a fifth of participants reported drug driving in the past six months. Additionally, the analysis indicated that punishment avoidance and vicarious punishment avoidance were predictors of the propensity to drug drive in the future. In contrast, there were indications that knowing of others apprehended for drug driving was not a sufficient deterrent. Sustained testing and publicity of the legislation and countermeasure appears needed to increase the deterrent impact for drug driving.

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Alginate microspheres are considered a promising material as a drug carrier in bone repair due to excellent biocompatibility, but their main disadvantage is low drug entrapment efficiency and non-controllable release. The aim of this study was to investigate the effect of incorporating mesoporous bioglass (MBG), non-mesoporous bioglass (BG) or hydroxyapatite (HAp) into alginate microspheres on their drug-loading and release properties. X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and atomic emission spectroscopy (AES) were used to analyse the composition, structure and dissolution of bioactive inorganic materials and their microspheres. Dexamethasone (DEX)-loading and release ability of four microspheres were tested in phosphate buffered saline with varying pHs. Results showed that the drug-loading capacity was enhanced with the incorporation of bioactive inorganic materials into alginate microspheres. The MBG/Alginate microspheres had the highest drug loading ability. DEX release from alginate microspheres correlated to the dissolution of MBG, BG and HAp in PBS, and that the pH was an efficient factor in controlling the DEX release; a high pH resulted in greater DEX release, whereas a low pH delayed DEX release. In addition, MBG/alginate, BG/alginate and HAp/alginate microspheres had varying apatite-formation and dissolution abilities, which indicate that the composites would behave differently with respect to bioactivity. The study suggests that microspheres made of a composite of bioactive inorganic materials and alginate have a bioactivity and degradation profile which greatly improves their drug delivery capacity, thus enhancing their potential applications as bioactive filler materials for bone tissue regeneration.

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Alcohol and drug dependency is a widespread health and social issue encountered by registered nurses in contemporary practice. A study aiming to describe the experiences of registered nurses working in an alcohol and drug unit in South East Queensland was implemented. Data were analysed via Giorgi’s phenomenological method and an unexpected but significant finding highlighted the frustration felt by registered nurses regarding experiences of stigma they identified in their daily work encounters. Secondary analysis confirmed the phenomenon of stigma with three themes: (1) inappropriate judgement; (2) advocacy; and (3) education. Resultantly, findings concluded registered nurses’ working in this field need to become advocates for their clients, ensuring professional conduct is upheld at all times. This paper recommends that stigma could be addressed by incorporating alcohol and other drug dependency subjects and clinical placements into the curriculum of the Bachelor of Nursing degrees, and in-services for all practising registered nurses.