989 research outputs found

    Searching the ideal inhaled vasodilator: From nitric oxide to prostacyclin

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    Today, the technique to directly administer vasodilators via the airway to treat pulmonary hypertension and to improve pulmonary gas exchange is widely accepted among clinicians. The flood of scientific work focussing on this new therapeutic concept had been initiated by a fundamental new observation by Pepke-Zaba {[}1] and Frostell in 1991 {[}2]: Both scientists reported, that inhalation of exogenous nitric oxide (NO) gas selectively dilates pulmonary vessels without a concomittant systemic vasodilation. No more than another decade ago NO was identified as an important endogenous vasodilator {[}3] while having merely been regarded an environmental pollutant before that time. Although inhaled NO proved to be efficacious, alternatives were sought-after due to NO's potential side-effects. In search for the ideal inhaled vasodilator another group of endogenous mediators - the prostanoids - came into the focus of interest. The evidence for safety and efficacy of inhaled prostanoids is - among a lot of other valuable work - based on a series of experimental and clinical investigations that have been performed or designed at the Institute for Surgical Research under the guidance and mentorship of Prof. Dr. med. Dr. h.c. mult. K. Messmer {[}4-19]. In the following, the current and newly emerging clinical applications of inhaled prostanoids and the experimental data which they are based on, will be reviewed. Copyright (C) 2002 S. Karger AG, Basel

    The role of microtubule movement in bidirectional organelle transport

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    We study the role of microtubule movement in bidirectional organelle transport in Drosophila S2 cells and show that EGFP-tagged peroxisomes in cells serve as sensitive probes of motor induced, noisy cytoskeletal motions. Multiple peroxisomes move in unison over large time windows and show correlations with microtubule tip positions, indicating rapid microtubule fluctuations in the longitudinal direction. We report the first high-resolution measurement of longitudinal microtubule fluctuations performed by tracing such pairs of co-moving peroxisomes. The resulting picture shows that motor-dependent longitudinal microtubule oscillations contribute significantly to cargo movement along microtubules. Thus, contrary to the conventional view, organelle transport cannot be described solely in terms of cargo movement along stationary microtubule tracks, but instead includes a strong contribution from the movement of the tracks.Comment: 24 pages, 5 figure

    A systematic review of the cost-effectiveness of targeted therapies for metastatic non-small cell lung cancer (NSCLC)

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    Background: Non-small cell lung cancer (NSCLC) imposes a substantial burden on patients, health care systems and society due to increasing incidence and poor survival rates. In recent years, advances in the treatment of metastatic NSCLC have resulted from the introduction of targeted therapies. However, the application of these new agents increases treatment costs considerably. The objective of this article is to review the economic evidence of targeted therapies in metastatic NSCLC. Methods: A systematic literature review was conducted to identify cost-effectiveness (CE) as well as cost-utility studies. Medline, Embase, SciSearch, Cochrane, and 9 other databases were searched from 2000 through April 2013 (including update) for full-text publications. The quality of the studies was assessed via the validated Quality of Health Economic Studies (QHES) instrument. Results: Nineteen studies (including update) involving the MoAb bevacizumab and the Tyrosine-kinase inhibitors erlotinib and gefitinib met all inclusion criteria. The majority of studies analyzed the CE of first-line maintenance and second-line treatment with erlotinib. Five studies dealt with bevacizumab in first-line regimes. Gefitinib and pharmacogenomic profiling were each covered by only two studies. Furthermore, the available evidence was of only fair quality. Conclusion: First-line maintenance treatment with erlotinib compared to Best Supportive Care (BSC) can be considered cost-effective. In comparison to docetaxel, erlotinib is likely to be cost-effective in subsequent treatment regimens as well. The insights for bevacizumab are miscellaneous. There are findings that gefitinib is cost-effective in first- and second-line treatment, however, based on only two studies. The role of pharmacogenomic testing needs to be evaluated. Therefore, future research should improve the available evidence and consider pharmacogenomic profiling as specified by the European Medicines Agency. Upcoming agents like crizotinib and afatinib need to be analyzed as well.BMB

    Modeling traffic jams in intracellular transport in axons

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    Irregularities in intracellular traffic in axons caused by mutations of molecular motors may lead to “traffic jams”, which often result in swelling of axons causing various neurodegenerative diseases. The purpose of this paper is to suggest a model of the formation of traffic jams in axons during molecular-motor-assisted transport of intracellular organelles utilizing transport equations developed in Smith and Simmons [1], which describe the motion of intracellular particles under the combined action of diffusion and motor-driven transport. According to this model, large intracellular organelles are transported in the cytoplasm by a combined action of diffusion and motor-driven transport. In an axon, organelles are transported away from the neuron’s body toward the axon’s terminal by kinesin-family molecular motors running on tracks composed by microtubules; old and used components are carried back toward neuron’s body by dynein-family molecular motors. Binding/detachment kinetic processes between the organelles and microtubules are specified by first rate reaction constants; these lead to coupling between the three organelle concentrations

    Combination fluticasone and salmeterol versus fixed dose combination budesonide and formoterol for chronic asthma in adults and children

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    BackgroundCombination therapies are frequently recommended as maintenance therapy for people with asthma, whose disease is not adequately controlled with inhaled steroids. Fluticasone/salmeterol (FP/SAL) and budesonide/formoterol (BUD/F) have been assessed against their respective monocomponents, but there is a need to compare these two therapies on a head-to-head basis.ObjectivesTo estimate the relative effects of fluticasone/salmeterol and budesonide/formoterol in terms of asthma control, safety and lung function.Search strategyWe searched the Cochrane Airways Group register of trials with prespecified terms. We performed additional hand searching of manufacturers' web sites and online trial registries. Searches are current to May 2008.Selection criteriaRandomised studies comparing fixed dose FP/SAL and BUD/ F were eligible, for a minimum of 12 weeks. Crossover studies were excluded. Our primary outcomes were: i) exacerbations requiring oral steroid bursts, ii) hospital admission and iii) serious adverse events.Data collection and analysisTwo authors independently assessed studies for inclusion in the review. We combined continuous data outcomes with a mean difference (MD), and dichotomous data outcomes with an odds ratio (OR).Main resultsFive studies met the review entry criteria (5537 participants). Primary outcomes: The odds of an exacerbation requiring oral steroids did not differ significantly between treatments (OR 0.89; 95% CI 0.73 to 1.09, three studies, 4515 participants). The odds of an exacerbation leading hospital admission were also not significantly different (OR 1.29; 95% CI 0.68 to 2.47, four studies, 4879 participants). The odds of serious adverse events did not differ significantly between treatments (OR 1.47; 95% CI 0.75, 2.86, three studies, 4054 participants). Secondary outcomes: Lung function outcomes, symptoms, rescue medication, exacerbations leading ED visit/hospital admission and adverse events were not significantly different between treatments.Authors' conclusionsThe evidence in this review indicates that differences in the requirement for oral steroids and hospital admission between BUD/F and FP/SAL do not reach statistical significance. However, the confidence intervals do not exclude clinically important differences between treatments in reducing exacerbations or causing adverse events. The width of the confidence intervals for the primary outcomes justify further trials in order to better determine the relative effects of these drug combinations. Although this review sought to assess the effects of these drugs in both adults and children, no trials were identified in the under-12s and research in this area is of a high priority

    Recommended practices for wind farm data collection and reliability assessment for O&M optimization

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    The paper provides a brief overview of the aims and main results of IEA Wind Task 33. IEA Wind Task 33 was an expert working group with a focus on data collection and reliability assessment for O & M optimization of wind turbines. The working group started in 2012 and finalized the work in 2016. The complete results of IEA Wind Task 33 are described in the expert group report on recommended practices for "Wind farm data collection and reliability assessment for O & M optimization" which will be published by IEA Wind in 2017. This paper briefly presents the background of the work, the recommended process to identify necessary data, and appropriate taxonomies structuring and harmonizing the collected entries. Finally, the paper summarizes the key findings and recommendations from the IEA Wind Task 33 work

    Tumor necrosis factor and lymphotoxin-alpha genetic polymorphisms and risk of relapse in childhood B-cell precursor acute lymphoblastic leukemia: a case-control study of patients treated with BFM therapy

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    BACKGROUND: Circulating levels of tumor necrosis factor (TNF) and lymphotoxin-α (LT-α) have been associated with outcome in solid and hematologic malignancies. Within the TNF gene and the LT-α gene, polymorphisms have been identified at nucleotide positions -308 and +252, respectively. The variant alleles for TNF are designated TNF1 and TNF2, the ones for LT-α LT-α (10.5 kb) and LT-α (5.5 kb). Of interest, TNF2 and LT-α (5.5 kb) were shown to be associated with higher TNF and LT-α plasma levels than their counterparts. In the present study, we investigated the associations of the above mentioned polymorphisms with risk of relapse in childhood acute lymphoblastic leukemia (ALL) treated according to Berlin-Frankfurt-Münster (BFM) protocols. METHODS: Matched case-control study of 64 relapsed and 64 successfully treated non-relapsed childhood B-cell precursor ALL patients of standard and intermediate risk for treatment failure. RESULTS: The odds ratio (OR) for the combined category of TNF1/TNF2 and TNF2/TNF2 genotypes in comparison to the TNF1/TNF1 genotype was 1.17 (95 % confidence interval (CI) = 0.53 - 2.56, P = 0.697). The ORs for the LT-α (10.5 kb/5.5 kb) and the LT-α (5.5 kb/5.5 kb) genotypes with reference to the LT-α (10.5 kb/10.5 kb) genotype were 2.17 (95 % CI = 0.84 - 5.58, P = 0.107) and 0.5 (95 % CI = 0.09 - 2.66, P = 0.418), respectively. CONCLUSIONS: Our results do not suggest a major role of the investigated genetic polymorphisms with regard to risk of relapse in standard- and intermediate-risk childhood B-cell precursor ALL treated according to BFM protocols

    Commissioning of the vacuum system of the KATRIN Main Spectrometer

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    The KATRIN experiment will probe the neutrino mass by measuring the beta-electron energy spectrum near the endpoint of tritium beta-decay. An integral energy analysis will be performed by an electro-static spectrometer (Main Spectrometer), an ultra-high vacuum vessel with a length of 23.2 m, a volume of 1240 m^3, and a complex inner electrode system with about 120000 individual parts. The strong magnetic field that guides the beta-electrons is provided by super-conducting solenoids at both ends of the spectrometer. Its influence on turbo-molecular pumps and vacuum gauges had to be considered. A system consisting of 6 turbo-molecular pumps and 3 km of non-evaporable getter strips has been deployed and was tested during the commissioning of the spectrometer. In this paper the configuration, the commissioning with bake-out at 300{\deg}C, and the performance of this system are presented in detail. The vacuum system has to maintain a pressure in the 10^{-11} mbar range. It is demonstrated that the performance of the system is already close to these stringent functional requirements for the KATRIN experiment, which will start at the end of 2016.Comment: submitted for publication in JINST, 39 pages, 15 figure
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