59 research outputs found
Degradation of organic pollutants in photocatalytic reactors
Titanium dioxide-mediated photocatalytic mineralization of oxalic acid and formic acid as model compounds were studied in
a laboratory-scale reactor and in a pilot equipment to promote the development of procedures for wastewater treatment.
Experimental results obtained by using various TiO2 catalysts indicate that the adsorption of the pollutant substrates on
the surface of the semiconductor particles is not directly correlated with the specific surface area of the adsorbent. The
initial rate of the photocatalytic degradation of the model compounds is enhanced by increasing the adsorption capability
of the titanium dioxide applied, but the overall mineralization efficiency is jointly determined by several factors such as
the crystal structure, the mean value and the distribution of the particle size, as well as the number of the hydroxyl groups
on the particle surface. The VP P90 TiO2 proved to be the most efficient photocatalyst for degradation of both model
compounds studied. Application of static mixer in the pilot equipment enhanced the rate of the photocatalytic mineralization
of formic acid by about 27%. This effect can be attributed to the increased interfacial mass transfer facilitating the movement
of photogenerated HO*
radicals from the catalyst surface or the boundary layer to the bulk solution
The cultural and geopolitical dimensions of nation-building in the Ukraine
Ukraine belongs among those young countries where the beginnings of democratisation and nation-building approximately coincided. While the development of nation states in Central Europe was usually preceded by the development of nations, the biggest dilemma in the Ukraine is whether a nation-state programme — parallel to the aim of state-building — is able to bring unfinished nation-building to completion. Ukraine sways between the EU and Russia with enormous amplitude. The alternating orientation between the West and the East can be ascribed to superpower ambitions reaching beyond Ukraine. Eventually, internal and external determinants are intertwined and mutually interact with one another. The aim of the paper is to explain the dilemmas arising from identity problems behind the Ukraine’s internal and external orientation
Peripheral blood derived gene panels predict response to infliximab in rheumatoid arthritis and Crohn’s disease
Background: Biological therapies have been introduced for the treatment of chronic inflammatory diseases including rheumatoid arthritis (RA) and Crohn's disease (CD). The efficacy of biologics differs from patient to patient. Moreover these therapies are rather expensive, therefore treatment of primary non-responders should be avoided.
Method: We addressed this issue by combining gene expression profiling and biostatistical approaches. We performed peripheral blood global gene expression profiling in order to filter the genome for target genes in cohorts of 20 CD and 19 RA patients. Then RT-quantitative PCR validation was performed, followed by multivariate analyses of genes in independent cohorts of 20 CD and 15 RA patients, in order to identify sets ofinterrelated genes that can separate responders from non-responders to the humanized chimeric anti-TNFalpha antibody infliximab at baseline.
Results: Gene panels separating responders from non-responders were identified using leave-one-out cross-validation test, and a pool of genes that should be tested on larger cohorts was created in both conditions.
Conclusions: Our data show that peripheral blood gene expression profiles are suitable for determining gene panels with high discriminatory power to differentiate responders from non-responders in infliximab therapy at baseline in CD and RA, which could be cross-validated successfully. Biostatistical analysis of peripheral blood gene expression data leads to the identification of gene panels that can help predict responsiveness of therapy and support the clinical decision-making process
MSTO1 is a cytoplasmic pro-mitochondrial fusion protein, whose mutation induces myopathy and ataxia in humans.
The protein MSTO1 has been localized to mitochondria and linked to mitochondrial morphology, but its specific role has remained unclear. We identified a c.22G > A (p.Val8Met) mutation of MSTO1 in patients with minor physical abnormalities, myopathy, ataxia, and neurodevelopmental impairments. Lactate stress test and myopathological results suggest mitochondrial dysfunction. In patient fibroblasts, MSTO1 mRNA and protein abundance are decreased, mitochondria display fragmentation, aggregation, and decreased network continuity and fusion activity. These characteristics can be reversed by genetic rescue. Short-term silencing of MSTO1 in HeLa cells reproduced the impairment of mitochondrial morphology and dynamics observed in the fibroblasts without damaging bioenergetics. At variance with a previous report, we find MSTO1 to be localized in the cytoplasmic area with limited colocalization with mitochondria. MSTO1 interacts with the fusion machinery as a soluble factor at the cytoplasm-mitochondrial outer membrane interface. After plasma membrane permeabilization, MSTO1 is released from the cells. Thus, an MSTO1 loss-of-function mutation is associated with a human disorder showing mitochondrial involvement. MSTO1 likely has a physiologically relevant role in mitochondrial morphogenesis by supporting mitochondrial fusion
Clinical outcomes in patients treated for coronary in-stent restenosis with drug-eluting balloons: Impact of high platelet reactivity.
BACKGROUND: The impact of high platelet reactivity (HPR) on clinical outcomes after elective percutaneous coronary interventions (PCI) with drug-eluting balloons (DEB) due to in-stent restenosis (ISR) is unknown. OBJECTIVE: We sought to evaluate the prognostic importance of HPR together with conventional risk factors in patients treated with DEB. METHODS: Patients treated with DEB due to ISR were enrolled in a single-centre, prospective registry between October 2009 and March 2015. Only patients with recent myocardial infarction (MI) received prasugrel, others were treated with clopidogrel. HPR was defined as an ADP-test >46U with the Multiplate assay and no adjustments were done based on results. The primary endpoint of the study was a composite of cardiovascular mortality, MI, any revascularization or stroke during one-year follow-up. RESULTS: 194 stable angina patients were recruited of whom 90% were treated with clopidogrel. Clinical characteristics and procedural data were available for all patients; while platelet function testing was performed in 152 subjects of whom 32 (21%) had HPR. Patients with HPR had a higher risk for the primary endpoint (HR: 2.45; CI: 1.01-5.92; p = 0.03). The difference was primarily driven by a higher risk for revascularization and MI. According to the multivariate analysis, HPR remained a significant, independent predictor of the primary endpoint (HR: 2.88; CI: 1.02-8.14; p = 0.04), while total DEB length and statin treatment were other independent correlates of the primary outcome. CONCLUSION: HPR was found to be an independent predictor of repeat revascularization and MI among elective patients with ISR undergoing PCI with DEB
Demonstration of Metabolic and Cellular Effects of Portal Vein Ligation Using Multi-Modal PET/MRI Measurements in Healthy Rat Liver.
OBJECTIVES: In the early recognition of portal vein ligation (PVL) induced tumor progression, positron emission tomography and magnetic resonance imaging (PET/MRI) could improve diagnostic accuracy of conventionally used methods. It is unknown how PVL affects metabolic patterns of tumor free hepatic tissues. The aim of this preliminary study is to evaluate the effect of PVL on glucose metabolism, using PET/MRI imaging in healthy rat liver. MATERIALS AND METHODS: Male Wistar rats (n = 30) underwent PVL. 2-deoxy-2-(18F)fluoro-D-glucose (FDG) PET/MRI imaging (nanoScan PET/MRI) and morphological/histological examination were performed before (Day 0) and 1, 2, 3, and 7 days after PVL. Dynamic PET data were collected and the standardized uptake values (SUV) for ligated and non-ligated liver lobes were calculated in relation to cardiac left ventricle (SUVVOI/SUVCLV) and mean liver SUV (SUVVOI/SUVLiver). RESULTS: PVL induced atrophy of ligated lobes, while non-ligated liver tissue showed compensatory hypertrophy. Dynamic PET scan revealed altered FDG kinetics in both ligated and non-ligated liver lobes. SUVVOI/SUVCLV significantly increased in both groups of lobes, with a maximal value at the 2nd postoperative day and returned near to the baseline 7 days after the ligation. After PVL, ligated liver lobes showed significantly higher tracer uptake compared to the non-ligated lobes (significantly higher SUVVOI/SUVLiver values were observed at postoperative day 1, 2 and 3). The homogenous tracer biodistribution observed before PVL reappeared by 7th postoperative day. CONCLUSION: The observed alterations in FDG uptake dynamics should be taken into account during the assessment of PET data until the PVL induced atrophic and regenerative processes are completed
The soluble guanylate cyclase activator cinaciguat prevents cardiac dysfunction in a rat model of type-1 diabetes mellitus
BACKGROUND: Diabetes mellitus (DM) leads to the development of diabetic cardiomyopathy, which is associated with altered nitric oxide (NO)-soluble guanylate cyclase (sGC)-cyclic guanosine monophosphate (cGMP) signalling. Cardioprotective effects of elevated intracellular cGMP-levels have been described in different heart diseases. In the current study we aimed at investigating the effects of pharmacological activation of sGC in diabetic cardiomyopathy. METHODS: Type-1 DM was induced in rats by streptozotocin. Animals were treated either with the sGC activator cinaciguat (10 mg/kg/day) or with placebo orally for 8 weeks. Left ventricular (LV) pressure-volume (P-V) analysis was used to assess cardiac performance. Additionally, gene expression (qRT-PCR) and protein expression analysis (western blot) were performed. Cardiac structure, markers of fibrotic remodelling and DNA damage were examined by histology, immunohistochemistry and TUNEL assay, respectively. RESULTS: DM was associated with deteriorated cGMP signalling in the myocardium (elevated phosphodiesterase-5 expression, lower cGMP-level and impaired PKG activity). Cardiomyocyte hypertrophy, fibrotic remodelling and DNA fragmentation were present in DM that was associated with impaired LV contractility (preload recruitable stroke work (PRSW): 49.5 +/- 3.3 vs. 83.0 +/- 5.5 mmHg, P < 0.05) and diastolic function (time constant of LV pressure decay (Tau): 17.3 +/- 0.8 vs. 10.3 +/- 0.3 ms, P < 0.05). Cinaciguat treatment effectively prevented DM related molecular, histological alterations and significantly improved systolic (PRSW: 66.8 +/- 3.6 mmHg) and diastolic (Tau: 14.9 +/- 0.6 ms) function. CONCLUSIONS: Cinaciguat prevented structural, molecular alterations and improved cardiac performance of the diabetic heart. Pharmacological activation of sGC might represent a new therapy approach for diabetic cardiomyopathy
Membrane-Lipid Therapy in Operation: The HSP Co-Inducer BGP-15 Activates Stress Signal Transduction Pathways by Remodeling Plasma Membrane Rafts
Aging and pathophysiological conditions are linked to membrane changes which modulate membrane-controlled molecular switches, causing dysregulated heat shock protein (HSP) expression. HSP co-inducer hydroxylamines such as BGP-15 provide advanced therapeutic candidates for many diseases since they preferentially affect stressed cells and are unlikely have major side effects. In the present study in vitro molecular dynamic simulation, experiments with lipid monolayers and in vivo ultrasensitive fluorescence microscopy showed that BGP-15 alters the organization of cholesterol-rich membrane domains. Imaging of nanoscopic long-lived platforms using the raft marker glycosylphosphatidylinositol-anchored monomeric green fluorescent protein diffusing in the live Chinese hamster ovary (CHO) cell plasma membrane demonstrated that BGP-15 prevents the transient structural disintegration of rafts induced by fever-type heat stress. Moreover, BGP-15 was able to remodel cholesterol-enriched lipid platforms reminiscent of those observed earlier following non-lethal heat priming or membrane stress, and were shown to be obligate for the generation and transmission of stress signals. BGP-15 activation of HSP expression in B16-F10 mouse melanoma cells involves the Rac1 signaling cascade in accordance with the previous observation that cholesterol affects the targeting of Rac1 to membranes. Finally, in a human embryonic kidney cell line we demonstrate that BGP-15 is able to inhibit the rapid heat shock factor 1 (HSF1) acetylation monitored during the early phase of heat stress, thereby promoting a prolonged duration of HSF1 binding to heat shock elements. Taken together, our results indicate that BGP-15 has the potential to become a new class of pharmaceuticals for use in ‘membrane-lipid therapy’ to combat many various protein-misfolding diseases associated with aging
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