92 resultados para Single drug dose


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BACKGROUND: An early response to antipsychotic treatment in patients with psychosis has been associated with a better course and outcome. However, factors that predict treatment response are not well understood. The onset of schizophrenia and related disorders has been associated with increased levels of stress and hyper-activation of the hypothalamic-pituitary-adrenal (HPA) axis. This study examined whether pituitary volume at the onset of psychosis may be a potential predictor of early treatment response in first-episode psychosis (FEP) patients. METHODS: We investigated the relationship between baseline pituitary volume and symptomatic treatment response over 12 weeks using mixed model analysis in a sample of 42 drug-naïve or early treated FEP patients who participated in a controlled dose-finding study of quetiapine fumarate. Logistic regression was used to examine predictors of treatment response. Pituitary volume was measured from magnetic resonance imaging scans that were obtained upon entry into the trial. RESULTS: Larger pituitary volume was associated with less improvement in overall psychotic symptoms (Brief Psychiatric Rating Scale (BPRS) P=0.031) and positive symptoms (BPRS positive symptom subscale P=0.010). Regardless of gender, patients with a pituitary volume at the 25th percentile (413 mm(3)) were approximately three times more likely to respond to treatment by week 12 than those at the 75th percentile (635 mm(3)) (odds ratio=3.07, CI: 0.90-10.48). CONCLUSION: The association of baseline pituitary volumes with early treatment response highlights the importance of the HPA axis in emerging psychosis. Potential implications for treatment strategies in early psychosis are discussed.

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From the onset of the first microscopic visualization of single fluorescent molecules in living cells at the beginning of this century, to the present, almost routine application of single molecule microscopy, the method has well-proven its ability to contribute unmatched detailed insight into the heterogeneous and dynamic molecular world life is composed of. Except for investigations on bacteria and yeast, almost the entire story of success is based on studies on adherent mammalian 2D cell cultures. However, despite this continuous progress, the technique was not able to keep pace with the move of the cell biology community to adapt 3D cell culture models for basic research, regenerative medicine, or drug development and screening. In this review, we will summarize the progress, which only recently allowed for the application of single molecule microscopy to 3D cell systems and give an overview of the technical advances that led to it. While initially posing a challenge, we finally conclude that relevant 3D cell models will become an integral part of the on-going success of single molecule microscopy.

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Estimating the use of illicit drugs in the general community is an important task with ramifications for law enforcement agencies, as well as health portfolios. Australia has four ongoing drug monitoring systems, including the AIC’s DUMA program, the National Drug Strategy Household Survey, the Illicit Drug Reporting System and the Ecstasy and Related Drug Reporting System. The systems vary in methods, but broadly they are reliant upon self-report data and may be subject to selection biases. The present study employed a completely different method. By chemically analysing sewerage water, the study produced daily estimates of consumption of methamphetamine, MDMA and cocaine. Samples were collected in November 2009 and November 2010 from a municipality in Queensland, with an population of over 150,000 people. Estimates were made of the average daily dose and average daily street value per 1,000 people. On the basis of estimated dose and price, the methamphetamine market appeared considerably stronger than either MDMA or cocaine. This paper explains the strengths and weaknesses of wastewater analysis. It considers the potential value of wastewater analysis in measuring net consumption of illicit drugs and the effectiveness of law enforcement agency strategies.

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A major challenge in human genetics is to devise a systematic strategy to integrate disease-associated variants with diverse genomic and biological data sets to provide insight into disease pathogenesis and guide drug discovery for complex traits such as rheumatoid arthritis (RA)1. Here we performed a genome-wide association study meta-analysis in a total of >100,000 subjects of European and Asian ancestries (29,880 RA cases and 73,758 controls), by evaluating ~10 million single-nucleotide polymorphisms. We discovered 42 novel RA risk loci at a genome-wide level of significance, bringing the total to 101 (refs 2, 3, 4). We devised an in silico pipeline using established bioinformatics methods based on functional annotation5, cis-acting expression quantitative trait loci6 and pathway analyses7, 8, 9—as well as novel methods based on genetic overlap with human primary immunodeficiency, haematological cancer somatic mutations and knockout mouse phenotypes—to identify 98 biological candidate genes at these 101 risk loci. We demonstrate that these genes are the targets of approved therapies for RA, and further suggest that drugs approved for other indications may be repurposed for the treatment of RA. Together, this comprehensive genetic study sheds light on fundamental genes, pathways and cell types that contribute to RA pathogenesis, and provides empirical evidence that the genetics of RA can provide important information for drug discovery.

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Single nucleotide polymorphisms (SNPs) have been classically used for dissecting various human complex disorders using candidate gene studies. During the last decade, large scale SNP analysis i.e. genome-wide association studies (GWAS) have provided an agnostic approach to identify possible genetic loci associated with heterogeneous disease such as cancer susceptibility, prognosis of survival or drug response. Further, the advent of new technologies, including microarray based genotyping as well as high throughput next generation sequencing has opened new avenues for SNPs to be used in clinical practice. It is speculated that the utility of SNPs to understand the mechanisms, biology of variable drug response and ultimately treatment individualization based on the individual’s genome composition will be indispensable in the near future. In the current review, we discuss the advantages and disadvantages of the clinical utility of genetic variants in disease risk-prediction, prognosis, clinical outcome and pharmacogenomics. The lessons and challenges for the utility of SNP based biomarkers are also discussed, including the need for additional functional validation studies.

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Metformin is the most commonly used pharmacological therapy for type 2 diabetes. We report a genome-wide association study for glycemic response to metformin in 1,024 Scottish individuals with type 2 diabetes with replication in two cohorts including 1,783 Scottish individuals and 1,113 individuals from the UK Prospective Diabetes Study. In a combined meta-analysis, we identified a SNP, rs11212617, associated with treatment success (n = 3,920, P = 2.9 P×-9, odds ratio = 1.35, 95% CI 1.22-1.49) at a locus containing ATM, the ataxia telangiectasia mutated gene. In a rat hepatoma cell line, inhibition of ATM with KU-55933 attenuated the phosphorylation and activation of AMP-activated protein kinase in response to metformin. We conclude that ATM, a gene known to be involved in DNA repair and cell cycle control, plays a role in the effect of metformin upstream of AMP-activated protein kinase, and variation in this gene alters glycemic response to metformin. © 2011 Nature America, Inc. All rights reserved.

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Study Design Retrospective review of prospectively collected data. Objectives To analyze intervertebral (IV) fusion after thoracoscopic anterior spinal fusion (TASF) and explore the relationship between fusion scores and key clinical variables. Summary of Background Information TASF provides comparable correction with some advantages over posterior approaches but reported mechanical complications, and their relationship to non-union and graft material is unclear. Similarly, the optimal combination of graft type and implant stiffness for effecting successful radiologic union remains undetermined. Methods A subset of patients from a large single-center series who had TASF for progressive scoliosis underwent low-dose computed tomographic scans 2 years after surgery. The IV fusion mass in the disc space was assessed using the 4-point Sucato scale, where 1 indicates <50% and 4 indicates 100% bony fusion of the disc space. The effects of rod diameter, rod material, graft type, fusion level, and mechanical complications on fusion scores were assessed. Results Forty-three patients with right thoracic major curves (mean age 14.9 years) participated in the study. Mean fusion scores for patient subgroups ranged from 1.0 (IV levels with rod fractures) to 2.2 (4.5-mm rod with allograft), with scores tending to decrease with increasing rod size and stiffness. Graft type (autograft vs. allograft) did not affect fusion scores. Fusion scores were highest in the middle levels of the rod construct (mean 2.52), dropping off by 20% to 30% toward the upper and lower extremities of the rod. IV levels where a rod fractured had lower overall mean fusion scores compared to levels without a fracture. Mean total Scoliosis Research Society (SRS) questionnaire scores were 98.9 from a possible total of 120, indicating a good level of patient satisfaction. Conclusions Results suggest that 100% radiologic fusion of the entire disc space is not necessary for successful clinical outcomes following thoracoscopic anterior selective thoracic fusion.

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- Background Nilotinib and dasatinib are now being considered as alternative treatments to imatinib as a first-line treatment of chronic myeloid leukaemia (CML). - Objective This technology assessment reviews the available evidence for the clinical effectiveness and cost-effectiveness of dasatinib, nilotinib and standard-dose imatinib for the first-line treatment of Philadelphia chromosome-positive CML. - Data sources Databases [including MEDLINE (Ovid), EMBASE, Current Controlled Trials, ClinicalTrials.gov, the US Food and Drug Administration website and the European Medicines Agency website] were searched from search end date of the last technology appraisal report on this topic in October 2002 to September 2011. - Review methods A systematic review of clinical effectiveness and cost-effectiveness studies; a review of surrogate relationships with survival; a review and critique of manufacturer submissions; and a model-based economic analysis. - Results Two clinical trials (dasatinib vs imatinib and nilotinib vs imatinib) were included in the effectiveness review. Survival was not significantly different for dasatinib or nilotinib compared with imatinib with the 24-month follow-up data available. The rates of complete cytogenetic response (CCyR) and major molecular response (MMR) were higher for patients receiving dasatinib than for those with imatinib for 12 months' follow-up (CCyR 83% vs 72%, p < 0.001; MMR 46% vs 28%, p < 0.0001). The rates of CCyR and MMR were higher for patients receiving nilotinib than for those receiving imatinib for 12 months' follow-up (CCyR 80% vs 65%, p < 0.001; MMR 44% vs 22%, p < 0.0001). An indirect comparison analysis showed no difference between dasatinib and nilotinib for CCyR or MMR rates for 12 months' follow-up (CCyR, odds ratio 1.09, 95% CI 0.61 to 1.92; MMR, odds ratio 1.28, 95% CI 0.77 to 2.16). There is observational association evidence from imatinib studies supporting the use of CCyR and MMR at 12 months as surrogates for overall all-cause survival and progression-free survival in patients with CML in chronic phase. In the cost-effectiveness modelling scenario, analyses were provided to reflect the extensive structural uncertainty and different approaches to estimating OS. First-line dasatinib is predicted to provide very poor value for money compared with first-line imatinib, with deterministic incremental cost-effectiveness ratios (ICERs) of between £256,000 and £450,000 per quality-adjusted life-year (QALY). Conversely, first-line nilotinib provided favourable ICERs at the willingness-to-pay threshold of £20,000-30,000 per QALY. - Limitations Immaturity of empirical trial data relative to life expectancy, forcing either reliance on surrogate relationships or cumulative survival/treatment duration assumptions. - Conclusions From the two trials available, dasatinib and nilotinib have a statistically significant advantage compared with imatinib as measured by MMR or CCyR. Taking into account the treatment pathways for patients with CML, i.e. assuming the use of second-line nilotinib, first-line nilotinib appears to be more cost-effective than first-line imatinib. Dasatinib was not cost-effective if decision thresholds of £20,000 per QALY or £30,000 per QALY were used, compared with imatinib and nilotinib. Uncertainty in the cost-effectiveness analysis would be substantially reduced with better and more UK-specific data on the incidence and cost of stem cell transplantation in patients with chronic CML. - Funding The Health Technology Assessment Programme of the National Institute for Health Research.

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BACKGROUND The current impetus for developing alcohol and/or other drugs (AODs) workplace policies in Australia is to reduce workplace AOD impairment, improve safety, and prevent AOD-related injury in the workplace. For these policies to be effective, they need to be informed by scientific evidence. Evidence to inform the development and implementation of effective workplace AOD policies is currently lacking. There does not currently appear to be conclusive evidence for the effectiveness of workplace AOD policies in reducing impairment and preventing AOD-related injury. There is also no apparent evidence regarding which factors facilitate or impede the success of an AOD policy, or whether, for example, unsuccessful policy outcomes were due to poor policy or merely poor implementation of the policy. It was the aim of this research to undertake a process, impact, and outcome evaluation of a workplace AOD policy, and to contribute to the body of knowledge on the development and implementation of effective workplace AOD policies. METHODS The research setting was a state-based power-generating industry in Australia between May 2008 and May 2010. Participants for the process evaluation study were individuals who were integral to either the development or the implementation of the workplace AOD policy, or both of these processes (key informants), and comprised the majority of individuals who were involved in the process of developing and/or implementing the workplace AOD policy. The sample represented the two main groups of interest—management and union delegates/employee representatives—from all three of the participating organisations. For the impact and outcome evaluation studies, the population included all employees from the three participating organisations, and participants were all employees who consented to participate in the study and who completed both the pre-and post-policy implementation questionnaires. Qualitative methods in the form of interviews with key stakeholders were used to evaluate the process of developing and implementing the workplace AOD policy. In order to evaluate the impact of the policy with regard to the risk factors for workplace AOD impairment, and the outcome of the policy in terms of reducing workplace AOD impairment, quantitative methods in the form of a non-randomised single group pre- and post-test design were used. Changes from Time 1 (pre) to Time 2 (post) in the risk factors for workplace AOD impairment, and changes in the behaviour of interest—(self-reported) workplace AOD impairment—were measured. An integration of the findings from the process, impact, and outcome evaluation studies was undertaken using a combination of qualitative and quantitative methods. RESULTS For the process evaluation study Study respondents indicated that their policy was developed in the context of comparable industries across Australia developing workplace AOD policies, and that this was mainly out of concern for the deleterious health and safety impacts of workplace AOD impairment. Results from the process evaluation study also indicated that in developing and implementing the workplace AOD policy, there were mainly ‗winners', in terms of health and safety in the workplace. While there were some components of the development and implementation of the policy that were better done than others, and the process was expensive and took a long time, there were, overall, few unanticipated consequences to implementing the policy and it was reported to be thorough and of a high standard. Findings also indicated that overall the policy was developed and implemented according to best-practice in that: consultation during the policy development phase (with all the main stakeholders) was extensive; the policy was comprehensive; there was universal application of the policy to all employees; changes in the workplace (with regard to the policy) were gradual; and, the policy was publicised appropriately. Furthermore, study participants' responses indicated that the role of an independent external expert, who was trusted by all stakeholders, was integral to the success of the policy. For the impact and outcome evaluation studies Notwithstanding the limitations of pre- and post-test study designs with regard to attributing cause to the intervention, the findings from the impact evaluation study indicated that following policy implementation, statistically significant positive changes with regard to workplace AOD impairment were recorded for the following variables (risk factors for workplace AOD impairment): Knowledge; Attitudes; Perceived Behavioural Control; Perceptions of the Certainty of being punished for coming to work impaired by AODs; Perceptions of the Swiftness of punishment for coming to work impaired by AODs; and Direct and Indirect Experience with Punishment Avoidance for workplace AOD impairment. There were, however, no statistically significant positive changes following policy implementation for Behavioural Intentions, Subjective Norms, and Perceptions of the Severity of punishment for workplace AOD impairment. With regard to the outcome evaluation, there was a statistically significant reduction in self-reported workplace AOD impairment following the implementation of the policy. As with the impact evaluation, these findings need to be interpreted in light of the limitations of the study design in being able to attribute cause to the intervention alone. The findings from the outcome evaluation study also showed that while a positive change in self-reported workplace AOD impairment following implementation of the policy did not appear to be related to gender, age group, or employment type, it did appear to be related to levels of employee general alcohol use, cannabis use, site type, and employment role. Integration of the process, impact, and outcome evaluation studies There appeared to be qualitative support for the relationship between the process of developing and implementing the policy, and the impact of the policy in changing the risk factors for workplace AOD impairment. That is, overall the workplace AOD policy was developed and implemented well and, following its implementation, there were positive changes in the majority of measured risk factors for workplace AOD impairment. Quantitative findings lend further support for a relationship between the process and impact of the policy, in that there was a statistically significant association between employee perceived fidelity of the policy (related to the process of the policy) and positive changes in some risk factors for workplace AOD impairment (representing the impact of the policy). Findings also indicated support for the relationship between the impact of the policy in changing the risk factors for workplace AOD impairment and the outcome of the policy in reducing workplace AOD impairment: positive changes in the risk factors for workplace AOD impairment (impact) were related to positive changes in self reported workplace AOD impairment (representing the main goal and outcome of the policy). CONCLUSIONS The findings from the research indicate support for the conclusion that the policy was appropriately implemented and that it achieved its objectives and main goal. The Doctoral research findings also addressed a number of gaps in the literature on workplace AOD impairment, namely: the likely effectiveness of AOD policies for reducing AOD impairment in the workplace, which factors in the development and implementation of a workplace AOD policy are likely to facilitate or impede the effectiveness of the policy to reduce workplace AOD impairment, and which employee groups are less likely to respond well to policies of this type. The findings from this research not only represent an example of translational, applied research—through the evaluation of the study industry's policy—but also add to the body of knowledge on workplace AOD policies and provide policy-makers with evidence which may be useful in the development and implementation of effective workplace AOD policies. Importantly, the findings espouse the importance of scientific evidence in the development, implementation, and evaluation of workplace AOD policies.

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The Raman spectra at 77 K of the hydroxyl stretching of kaolinite were obtained along the three axes perpendicular to the crystal faces. Raman bands were observed at 3616, 3658 and 3677 cm−1 together with a distinct band observed at 3691 cm−1 and a broad profile between 3695 and 3715 cm−1. The band at 3616 cm−1 is assigned to the inner hydroxyl. The bands at 3658 and 3677 cm−1 are attributed to the out-of-phase vibrations of the inner surface hydroxyls. The Raman spectra of the in-phase vibrations of the inner-surface hydroxyl-stretching region are described in terms of transverse and longitudinal optic splitting. The band at 3691 cm−1 is assigned to the transverse optic and the broad profile to the longitudinal optic mode. This splitting remained even at liquid nitrogen temperature. The transverse optic vibration may be curve resolved into two or three bands, which are attributed to different types of hydroxyl groups in the kaolinite.