84 research outputs found

    Physical interaction between MYCN oncogene and polycomb repressive complex 2 (PRC2) in neuroblastoma: Functional and therapeutic implications

    Get PDF
    This article is made available through the Brunel Open Access Publishing Fund. © 2013 by The American Society for Biochemistry and Molecular Biology, Inc.CLU (clusterin) is a tumor suppressor gene that we have previously shown to be negatively modulated by the MYCN proto-oncogene, but the mechanism of repression was unclear. Here, we show that MYCN inhibits the expression of CLU by direct interaction with the non-canonical E box sequence CACGCG in the 5′-flanking region. Binding of MYCN to the CLU gene induces bivalent epigenetic marks and recruitment of repressive proteins such as histone deacetylases and Polycomb members. MYCN physically binds in vitro and in vivo to EZH2, a component of the Polycomb repressive complex 2, required to repress CLU. Notably, EZH2 interacts with the Myc box domain 3, a segment of MYC known to be essential for its transforming effects. The expression of CLU can be restored in MYCN-amplified cells by epigenetic drugs with therapeutic results. Importantly, the anticancer effects of the drugs are ablated if CLU expression is blunted by RNA interference. Our study implies that MYC tumorigenesis can be effectively antagonized by epigenetic drugs that interfere with the recruitment of chromatin modifiers at repressive E boxes of tumor suppressor genes such as CLU.SPARKS, The Neuroblastoma Society, a Wellcome Trust grant (to A. S.), and the Italian Association for Cancer Research

    Challenging inhibitory control with high- and low-calorie food: A behavioural and TMS study

    Get PDF
    Most people are often tempted by their impulses to “indulge” in high-calorie food, even if this behaviour is not consistent with their goal to control weight in the long term and might not be healthy. The outcome of this conflict is strongly dependent on inhibitory control. It has already been reported that individuals with weaker inhibitory control consume more high-calorie food, are more often unsuccessful dieters, overweight or obese compared to people with more effective inhibitory control. In the present study, we aimed at investigating inhibitory control in the context of human eating behaviour. A sample of 20 healthy normal-weight adults performed a 50% probability visual affective Go/NoGo task involving food (high- and low-calorie) and non-food images as stimuli. Single-pulse transcranial magnetic stimulation (TMS) was administered over the right primary motor cortex (M1) either 300 ms after image presentation to measure corticospinal excitability during the different stimulus categories or 300 ms after the appearance of a fixation point, as a control stimulation condition. The experimental session consisted of a food target and a non-food target block. Behavioural outcomes showed a natural implicit inclination towards high-calorie food in that participants were faster and more accurate compared to the other categories. This advantage was selectively deleted by TMS, which slowed down reaction times. MEPs did not differ according to the stimulus category, but, as expected, were bigger for Go compared to NoGo trials. Participants judged high-calorie food also as more appetising than low-calorie food images. Overall, our results point to a differential modulation when targeting inhibitory control, in favour of the more palatable food category (high-calorie). Present data suggest that the activity of the motor system is modulated by food nutritional value, being more engaged by appetising food. Future work should explore to what extent these processes are affected in patients with eating disorders and should aim to better characterise the related dynamics of cortical connectivity within the motor network

    Skin wetness sensitivity across body sites commonly affected by pain in people with migraine

    Get PDF
    Objective: The objective of this study was to evaluate skin wetness perception and thermal sensitivity in people with migraine and similar healthy controls.Background: Environmental triggers, such as cold and humidity, are known triggers for pain in people with migraine. Sensory inputs might be implicated in such heightened responses to cold-humid environments, such that a migraine-induced hypersensitivity to cold wetness could be present in people with migraine. However, we lack empirical evidence on skin thermal and wetness sensitivity across skin sites commonly associated with reported pain in migraine, such as the forehead.Methods: This prospective cross-sectional observational study, conducted in a university hospital setting, evaluated skin wetness perceptions and thermal sensations to wet non-noxious warm-wet, neutral-wet, and cold-wet stimuli applied to the forehead, the posterior neck, and the index finger pad of 12 patients with migraine (mean and standard deviation for age 44.5 +/- 13.2 years, 7/12 [58%] women) and 36 healthy controls (mean and standard deviation for age 39.4 +/- 14.6 years, 18/36 [50%] women).Results: On the forehead, people with migraine reported a significantly higher wetness perception than healthy controls across all thermal stimulus (15.1 mm, 95% confidence interval [CI]: 1.8 to 28.5, p = 0.027, corresponding to similar to 15% difference), whereas no significant differences were found on the posterior neck nor on the index finger pad. We found no differences among groups in overall thermal sensations (-8.3 mm, 95% CI: -24.0 to 7.3, p = 0.291; -7.8 mm, 95% CI: -25.3 to 9.7, p = 0.375; and 12.4 mm, 95% CI: -4.0 to 28.9, p = 0.133; forehead, posterior neck, and index finger, respectively).Conclusion: These findings indicate that people with migraine have a heightened sensitivity to skin wetness on the forehead area only, which is where pain attacks occur. Future studies should further explore the underlying mechanisms (e.g., TRPM8-mediated cold-wet allodynia) that lead to greater perception of wetness in people with migraine to better understand the role of environmental triggers in migraine

    Open Source evaluation of kilometric indexes of abundance.

    Get PDF
    Kilometric Abundance Index (KAI) is a common measure used in wildlife studies because it allows a straightforward comparison of species abundance in different sites or at different times. KAI expresses the ratio of the total number of individuals (or of signs of presence) observed along a transect by the total transect length covered at each site. v.transect.kia is a new tool for GRASS GIS, developed for automating the evaluation of KAI, reducing the risk of manual errors especially when handling large datasets. It can also split the transects according to one environmental variable (typically habitat type) and evaluate true 3D transect length. It calculates KAI using a point map of sightings and saves the results in the attribute table, the output can be displayed in any GIS or used for further statistical analysis. The tool has been tested on field data from Northern Italy for mountain hare (Lepus timidus), allowing a first wide-area estimate

    Poly(Vinyl alcohol)/gelatin scaffolds allow regeneration of nasal tissues

    Get PDF
    Need for regeneration and repair of nasal tissues occurs as a consequence of several pathologies affecting the nose, including, but not limited to infective diseases, traumas and tumor resections. A platform for nasal tissue regeneration was set up using poly(vinyl alcohol)/gelatin sponges with 20%–30% (w/w) gelatin content to be used as scaffolds, for their intrinsic hydrophilic, cell adhesive and shape recovery properties. We propose mesodermal progenitor cells (MPCs) isolated from the bone marrow as a unique stem cell source for obtaining different connective tissues of the nose, including vascular tissue. Finally, epithelial cell immune response to these scaffolds was assessed in vitro in an environment containing inflammatory molecules. The results showed that mesenchymal stromal cells (MSCs) deriving from MPCs could be used to differentiate into cartilage and fibrous tissue; whereas, in combination with endothelial cells still deriving from MPCs, into pre-vascularized bone. Finally, the scaffold did not significantly alter the epithelial cell response to inflammatory insults derived from interaction with bacterial molecules

    Regional Precuneus Cortical Hyperexcitability in Alzheimer's Disease Patients

    Get PDF
    Objective: Neuronal excitation/inhibition (E/I) imbalance is a potential cause of neuronal network malfunctioning in Alzheimer's disease (AD), contributing to cognitive dysfunction. Here, we used a novel approach combining transcranial magnetic stimulation (TMS) and electroencephalography (EEG) to probe cortical excitability in different brain areas known to be directly involved in AD pathology. Methods: We performed TMS-EEG recordings targeting the left dorsolateral prefrontal cortex (l-DLPFC), the left posterior parietal cortex (l-PPC), and the precuneus (PC) in a large sample of patients with mild-to-moderate AD (n = 65) that were compared with a group of age-matched healthy controls (n = 21). Results: We found that patients with AD are characterized by a regional cortical hyperexcitability in the PC and, to some extent, in the frontal lobe, as measured by TMS-evoked potentials. Notably, cortical excitability assessed over the l-PPC was comparable between the 2 groups. Furthermore, we found that the individual level of PC excitability was associated with the level of cognitive impairment, as measured with Mini-Mental State Examination, and with corticospinal fluid levels of Aβ42 . Interpretation: Our data provide novel evidence that precuneus cortical hyperexcitability is a key feature of synaptic dysfunction in patients with AD. The current results point to the combined approach of TMS and EEG as a novel promising technique to measure hyperexcitability in patients with AD. This index could represent a useful biomarker to stage disease severity and evaluate response to novel therapies. ANN NEUROL 2022

    Functional connectivity studies in migraine: What have we learned?

    Get PDF
    Background: Resting-state functional connectivity (FC) MRI has widely been used to understand migraine pathophysiology and to identify an imaging marker of the disorder. Here, we review what we have learned from FC studies. Methods: We performed a literature search on the PubMed website for original articles reporting data obtained from conventional resting-state FC recording in migraine patients compared with healthy controls or during and outside of migraine attacks in the same patients. Results: We found 219 articles and included 28 in this review after screening for inclusion and exclusion criteria. Twenty-five studies compared migraine patients with healthy controls, whereas three studies investigated migraine patients during and outside of attacks. In the studies of interictal migraine more alterations of more than 20 FC networks (including amygdala, caudate nucleus, central executive, cerebellum, cuneus, dorsal attention network, default mode, executive control, fronto-parietal, hypothalamus, insula, neostriatum, nucleus accumbens, occipital lobe, periaqueductal grey, prefrontal cortex, salience, somatosensory cortex I, thalamus and visual) were reported. We found a poor level of reproducibility and no migraine specific pattern across these studies. Conclusion: Based on the findings in the present review, it seems very difficult to extract knowledge of migraine pathophysiology or to identify a biomarker of migraine. There is an unmet need of guidelines for resting-state FC studies in migraine, which promote the use of homogenous terminology, public availability of protocol and the a priori hypothesis in line with for instance randomized clinical trial guidelines
    • …
    corecore