50 research outputs found
MicroRNAs: new players in acute myeloid leukaemia
MicroRNAs (miRNAs) are short non-coding RNAs that have key functions in a wide array of critical cell processes, including haematopoiesis by regulating the expression of multiple genes. Aberrant miRNA expression has been described in acute myeloid leukaemia suggesting a role in leukaemogenesis. In this review we summarise the current knowledge
Impact of inactivity and exercise on the vasculature in humans
The effects of inactivity and exercise training on established and novel cardiovascular risk factors are relatively modest and do not account for the impact of inactivity and exercise on vascular risk. We examine evidence that inactivity and exercise have direct effects on both vasculature function and structure in humans. Physical deconditioning is associated with enhanced vasoconstrictor tone and has profound and rapid effects on arterial remodelling in both large and smaller arteries. Evidence for an effect of deconditioning on vasodilator function is less consistent. Studies of the impact of exercise training suggest that both functional and structural remodelling adaptations occur and that the magnitude and time-course of these changes depends upon training duration and intensity and the vessel beds involved. Inactivity and exercise have direct “vascular deconditioning and conditioning” effects which likely modify cardiovascular risk
Inferior outcome of addition of the aminopeptidase inhibitor tosedostat to standard intensive treatment for elderly patients with aml and high risk mds
Treatment results of AML in elderly patients are unsatisfactory. We hypothesized that addition of tosedostat, an aminopeptidase inhibitor, to intensive chemotherapy may improve outcome in this population. After establishing a safe dose in a run-in phase of the study in 22 patients, 231 eligible patients with AML above 65 years of age (median 70, range 66–81) were randomly assigned in this open label randomized Phase II study to receive standard chemotherapy (3+7) with or without tosedostat at the selected daily dose of 120 mg (n = 116), days 1–21. In the second cycle, patients received cytarabine 1000 mg/m2 twice daily on days 1-6 with or without tosedostat. CR/CRi rates in the 2 arms were not significantly different (69% (95% C.I. 60–77%) vs 64% (55–73%), respectively). At 24 months, event-free survival (EFS) was 20% for the standard arm versus 12% for the tosedostat arm (Cox-p = 0.01) and overall survival (OS) 33% vs 18% respectively (p = 0.006). Infectious complications accounted for an increased early death rate in the tosedostat arm. Atrial fibrillation w
Photocatalytically active TiO2 thin films produced by surfactant-assisted sol-gel processing
Thin TiO2 films were prepared from a titanium isopropoxide precursor by sol\u2013gel processing with or without various nonionic surfactant molecules (Brij 56, Triton X-100 or Pluronic F-127). The photocatalytic efficiency of the transparent films obtained by a dip-coating technique was found to depend strongly on the use of and type of surfactant added. Titania/Pluronic sols resulted in homogeneous and crack-free TiO2 anatase films with a thickness as much as 300 nm after one dipping and heat-treatment (500 \ub0C) cycle. Optical properties of the films were characterized by UV-Vis spectroscopy and crystalline structures by X-ray diffraction. A surfactant-assisted sol\u2013gel process retarded crystallization of the anatase titania films, which resulted in smaller grain sizes (down to 10 nm) and presumably a larger active surface area. The morphology of the film surfaces as obtained by SEM techniques could be also correlated with the results of our photodegradation studies. The photocatalytic activity of the films was enhanced by first coating the glass substrate with a SiO2 protective layer prior to the deposition of the titania film. For our in situ studies of photodegradation we chose the monoazo dye Plasmocorinth B as a model compound as it is stable under environmental conditions and its degradation products are not coloured. The highest photobleaching rate was found for films deposited from the sol with addition of the Pluronic surfactant and it was almost twice as high as that for films deposited from sols without the surfactant
Photocatalytic TiO2 Coatings: Effect of Substrate and Template
Transparent TiO2 films with a high photodegradation activity towards an azo dye in aqueous solution were prepared by sol\u2013gel processing. Films on soda\u2013lime glass supports protected with a thin silica barrier layer exhibited better crystallization and monodisperse nanoparticles, higher absorption of light below 370\u2009nm, and higher photocatalytic activity than those films deposited on bare glass supports proving the detrimental effect of interdiffused sodium ions on the development of the anatase nanostructure. The effect of substrate was more pronounced in thinner films (300\u2009nm) than in thicker ones (1200\u2009nm), which were achieved by adding a template (i.e. Pluronic F127) to the sol
TiO2-anatase films made by sol-gel processing and their photodegradation activity towards pollutants in water
Titanium dioxide has become the material of choice for hydrophilic photocatalytic
surfaces and the sol-gel technique has emerged as one of the most promising techniques for
growing TiO2 thin films. This chapter describes our sol-gel preparation and utilization of thin
titania films on glass substrates as catalysts for photodegradation of organic pollutants, such as
azo dyes and pesticides in aqueous solutions. The good photoefficiency of the as-prepared films
relies on their high contact surface area and nanocrystalline structure, which facilitates efficient
photoinduced electron-hole pair generation.
Transparent TiO2-anatase films on soda-lime glass supports were produced by two
different sol-gel processing routes: (i) dip coating from alcoholic sols containing surfactants and
followed by heat treatment at 500\ub0C; (ii) dip coating from aqueous sols after extended refluxing
treatment and followed by heating at ~100\ub0C. In both cases the starting precursor was titanium
alkoxide and the final coating consisted of a dominant anatase crystalline phase. In case of the
high-temperature processing route, the detrimental effect of interdiffused sodium ions from the
glass substrate during heat treatment was prevented by depositing a thin silica barrier layer prior
to titania deposition. The intermediate barrier layer was not needed in case of the lowtemperature
processing route, where the crystallization of anatase has been already promoted
during the formation of the sol. X-ray absorption spectroscopy and X-ray diffraction were applied
to determine the structure development at different stages from the precursor solution to the solid
thin film. Surface morphology, characterized by monodispersed or joint nanoparticles and
variable roughness, was investigated with atomic force microscopy, while the surface and indepth
composition of films were analyzed by X-ray photoelectron spectroscopy.
A photocatalytic activity of the as-prepared films was studied in two different tailor-made
photoreactors filled with an aqueous solution of certain pollutant. In case of an azo dye, the films
were immersed in its colored solution and photobleaching was followed in-situ with the help of
UV-VIS spectroscopy. The degradation of the pesticide was monitored by HPLC analysis and its
mineralization by ionic chromatography. The insecticide thiacloprid was stable under irradiation
(wavelength range 310-400 nm) in the absence of TiO2 films during 8 hours long period, whereas
in the presence of best-performing titania films the half time of the parent molecule was typically
15 minutes. The titania catalyst can be easily removed from the solution, which is one of the
principal advantages of using the immobilized films as catalysts rather than powders