2,273 research outputs found

    Transcriptional alterations under continuous or pulsatile dopaminergic treatment in dyskinetic rats

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    Continuous dopaminergic treatment is considered to prevent or delay the occurrence of dyskinesia in patients with Parkinson's disease (PD). Rotigotine is a non-ergolinic D3>D2>D1 dopamine-receptor agonist for the treatment of PD using a transdermal delivery system providing stable plasma levels. We aimed to investigate the differential influence on gene expression of pulsatile l-DOPA or rotigotine versus a continuous rotigotine treatment. The gene expression profile within the nigro-striatal system of unilateral 6-hydroxydopamine-lesioned rats was assessed in order to differentiate potential changes in gene expression following the various treatment using Affymetrix microarrays and quantitative RT-PCR. The expression of 15 genes in the substantia nigra and of 11 genes in the striatum was altered under pulsatile treatments inducing dyskinetic motor response, but was unchanged under continuous rotigotine treatment that did not cause dyskinetic motor response. The route of administration of a dopaminergic drug is important for the induction or prevention of motor abnormalities and adaptive gene expressions. The decline of neurotrophin-3 expression under pulsatile administration was considered of particular importanc

    The competitive NMDA antagonist CPP protects substantia nigra neurons from MPTP-induced degeneration in primates

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    Degeneration of nigrostriatal dopaminergic neurons is the primary histopathological feature of Parkinson's disease. The neurotoxin MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) induces a neurological syndrome in man and non-human primates very similar to idiopathic Parkinson's disease by selectively destroying dopaminergic nigrostriatal neurons. This gives rise to the hypothesis that Parkinson's disease may be caused by endogenous or environmental toxins. Endogenous excitatory amino acids (EAAs) such as L-glutamate could be involved in neurodegenerative disorders including Parkinson's disease. We report in this study that the competitive NMDA antagonist CPP (3-((+/-)-2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid) protects nigral tyrosine hydroxylase (TH) positive neurons from degeneration induced by systemic treatment with MPTP in common marmosets. This indicates that EAAs are involved in the pathophysiological cascade of MPTP-induced neuronal cell death and that EAA antagonists may offer a neuroprotective therapy for Parkinson's disease

    Headache in 25 consecutive patients with atrial septal defects before and after percutaneous closure – a prospective case series

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    In contrast to patent foramen ovale, that is highly prevalent in the general population, atrial septal defect (ASD) is a rare congenital heart defect. The effect of ASD closure on headache and migraine remains a matter of controversy. The objectives of the study were (i) to determine headache prevalence in consecutive patients with ASD scheduled for percutaneous closure for cardiologic indications, using the classification of the International Headache Society and (ii) to compare headache characteristics before and after closure of ASD. In this observational case series no a priori power analysis was performed. Twenty-five consecutive patients were prospectively included over 27 months. Median duration of follow-up was 12 months, [Interquartile range 0]. Prevalence of active headache seemed to be increased compared to the general population: Any headaches 88% (95% confidence interval 70-96), migraine without aura 28% (14-48), migraine with aura 16% (6-35). After ASD closure, we observed a slightly lower headache frequency (median frequency 1.0 [2.6] vs. 0.3 [1.5] headaches per month; p=0.067). In patients with ongoing headaches, a significant decrease in headache intensity (median VAS 7 [3] vs. 5 [4]; p=0.036) was reported. Three patients with migraine with aura before the intervention reported no migraine with aura attacks at followup, two of them reported ongoing tension-type headache, one migraine without aura. In summary, this prospective observational study confirms the high prevalence of headache, particularly migraine, in ASD patients and suggests a possible small beneficial effect of ASD closure

    Modeling sporadic alzheimer's disease: the insulin resistant brain state generates multiple long-term morphobiological abnormalities inclusive hyperphosphorylated tau protein and amyloid-beta. A Synthesis

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    Nosologically, Alzheimer's disease (AD) is not a single disorder. Missense gene mutations involved in increased formation of the amyloid-beta protein precursor derivatives amyloid-beta (Abeta)_{1-40} and Abeta_{1-42/43} lead to autosomal dominant familial AD, found in the minority of AD cases. However, millions of subjects suffer from sporadic AD (sAD) of late onset, for which no convincing evidence suggests Abeta as the primary disease-generating compound. Environmental factors operating during pregnancy and postnatally may affect susceptibility genes and stress factors (e.g., cortisol), consequently affecting brain development both structurally and functionally, causing disorders becoming manifest late in life. With aging, a desynchronization of biological systems may result, increasing further brain entropy/declining criticality. In sAD, this desynchronization may involve stress components, cortisol and noradrenaline, reactive oxygen species, and membrane damage as major candidates causing an insulin resistant brain state with decreased glucose/energy metabolism. This further leads to a derangement of ATP-dependent cellular and molecular work, of the cell function in general, as well as derangements in the endoplasmic reticulum/Golgi apparatus, axon, synapses, and membranes, in particular. A self-propagating process is thus generated, including the increased formation of hyperphosphorylated tau-protein and Abeta as abnormal terminal events in sAD rather than causing the disorder, as elaborated in the review

    Estimation of the solubility parameters of model plant surfaces and agrochemicals: a valuable tool for understanding plant surface interactions

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    Background Most aerial plant parts are covered with a hydrophobic lipid-rich cuticle, which is the interface between the plant organs and the surrounding environment. Plant surfaces may have a high degree of hydrophobicity because of the combined effects of surface chemistry and roughness. The physical and chemical complexity of the plant cuticle limits the development of models that explain its internal structure and interactions with surface-applied agrochemicals. In this article we introduce a thermodynamic method for estimating the solubilities of model plant surface constituents and relating them to the effects of agrochemicals. Results Following the van Krevelen and Hoftyzer method, we calculated the solubility parameters of three model plant species and eight compounds that differ in hydrophobicity and polarity. In addition, intact tissues were examined by scanning electron microscopy and the surface free energy, polarity, solubility parameter and work of adhesion of each were calculated from contact angle measurements of three liquids with different polarities. By comparing the affinities between plant surface constituents and agrochemicals derived from (a) theoretical calculations and (b) contact angle measurements we were able to distinguish the physical effect of surface roughness from the effect of the chemical nature of the epicuticular waxes. A solubility parameter model for plant surfaces is proposed on the basis of an increasing gradient from the cuticular surface towards the underlying cell wall. Conclusions The procedure enabled us to predict the interactions among agrochemicals, plant surfaces, and cuticular and cell wall components, and promises to be a useful tool for improving our understanding of biological surface interactions

    The legal and ethical framework governing Body Donation in Europe-1st update on current practice

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    Previously, we have reported on the legal and ethical aspects and current practice of body donation in several European countries, reflecting cultural and religious variations as well as different legal and constitutional frameworks. We have also established good practice in body donation. Here we shall further extend the legal and ethical frameworks in place and also focus on novelties in the law and different directives. Of particular interest are points that address the commercialization of human bodies and body parts and weaknesses in the legal directives. Therefore, it is important to define what is ethical and what needs to be considered unethical in body donation and the subsequent utilisation of human bodies for teaching and research.peer-reviewe

    Molecular semiconductors and the Ioffe–Regel criterion: A terahertz study on band transport in DBTTT

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    Terahertz electromodulation spectroscopy provides insight into the physics of charge carrier transport in molecular semiconductors. The work focuses on thin-film devices of dibenzothiopheno[6,5-b:6′,5′-f]thieno[3,2-b]thiophene. Frequency-resolved data show a Drude-like response of the hole gas in the accumulation region. The temperature dependence of the mobilities follows a T1/2 power law. This indicates that the thermal mean free path of the charge carriers is restricted by disorder. Only a fraction of approximately 5% of the injected carriers fulfills the Ioffe–Regel criterion and participates in band transport.info:eu-repo/semantics/publishe

    Alcohol-related brain damage in humans

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    Chronic excessive alcohol intoxications evoke cumulative damage to tissues and organs. We examined prefrontal cortex (Brodmann’s area (BA) 9) from 20 human alcoholics and 20 age, gender, and postmortem delay matched control subjects. H & E staining and light microscopy of prefrontal cortex tissue revealed a reduction in the levels of cytoskeleton surrounding the nuclei of cortical and subcortical neurons, and a disruption of subcortical neuron patterning in alcoholic subjects. BA 9 tissue homogenisation and one dimensional polyacrylamide gel electrophoresis (PAGE) proteomics of cytosolic proteins identified dramatic reductions in the protein levels of spectrin β II, and α- and β-tubulins in alcoholics, and these were validated and quantitated by Western blotting. We detected a significant increase in α-tubulin acetylation in alcoholics, a non-significant increase in isoaspartate protein damage, but a significant increase in protein isoaspartyl methyltransferase protein levels, the enzyme that triggers isoaspartate damage repair in vivo. There was also a significant reduction in proteasome activity in alcoholics. One dimensional PAGE of membrane-enriched fractions detected a reduction in β-spectrin protein levels, and a significant increase in transmembranous α3 (catalytic) subunit of the Na+,K+-ATPase in alcoholic subjects. However, control subjects retained stable oligomeric forms of α-subunit that were diminished in alcoholics. In alcoholics, significant loss of cytosolic α- and β-tubulins were also seen in caudate nucleus, hippocampus and cerebellum, but to different levels, indicative of brain regional susceptibility to alcohol-related damage. Collectively, these protein changes provide a molecular basis for some of the neuronal and behavioural abnormalities attributed to alcoholics
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