86 research outputs found
M2 muscarinic receptor activation inhibits cell proliferation and migration of rat adipose-mesenchymal stem cells
Mesenchymal stem cells (MSCs), also known as stromal mesenchymal stem cells, are multipotent cells, which can be found in many tissues and organs as bone marrow, adipose tissue and other tissues. In particular MSCs derived from Adipose tissue (ADSCs) are the most frequently used in regenerative medicine because they are easy to source, rapidly expandable in culture and excellent differentiation potential into adipocytes, chondrocytes and other cell types. Acetylcholine (ACh), is one of the most important neurotransmitter in central (CNS) and peripheral nervous system (PNS), playing important roles also in non-neural tissue, but its functions in MSCs are still not investigated. Although MSCs express muscarinic receptor subtypes, their role is completely unknown. In present work muscarinic cholinergic effects were characterized in rat ADSCs. Analysis by RT-PCR demonstrates that ADSCs express M1-M4 muscarinic receptor subtypes, whereas M2 is one of the most expressed subtype. For this reason, our attention was focused on M2 subtype. By using the selective M2 agonist Arecaidine Propargyl Ester (APE) we performed cell proliferation and migration assays demonstrating that APE causes cell growth and migration inhibition without affecting cell survival. Our results indicate that ACh via M2 receptors, may contribute to the maintaining of the ADSCs quiescent status. These data are the first evidence that ACh via muscarinic receptors might contribute to control ADSCs physiology
Tumor suppressor Nf2/merlin drives Schwann cell changes following electromagnetic field exposure through Hippo-dependent mechanisms
Previous evidence showed mutations of the neurofibromin type 2 gene (Nf2), encoding the tumor suppressor protein merlin, in sporadic and vestibular schwannomas affecting Schwann cells (SC). Accordingly, efforts have been addressed to identify possible factors, even environmental, that may regulate neurofibromas growth. In this context, we investigated the exposure of SC to an electromagnetic field (EMF), which is an environmental issue modulating biological processes. Here we show that SC exposed to 50 Hz EMFs change their morphology, proliferation, migration and myelinating capability. In these cells merlin is downregulated, leading to activation of two intracellular signaling pathways, ERK/AKT and Hippo. Interestingly, SC change their phenotype toward a proliferative/migrating state, which in principle may be pathologically relevant for schwannoma development
Reevaluating the function of a transcription factor: MBF-1 as a sea urchin chromatin organizer ?
The Zinc-finger MBF-1 factor is involved in the expression of the early histone genes during devel-opment of the sea urchin embryo (1, 2). In spite of being a transcription activator, the DNA-binding domain of MBF-1 shares high sequence similarity with that of the chromatin organizer CTCF of vertebrates and drosophila (3). On the other hand, extensive in silico analysis failed to identify the sea urchin CTCF ortholog (4). This led us to speculate that MBF-1 somehow could have co-opted the function of CTCF during evolution of the echinoderms. Since in vertebrates CTCF binds Hox chromatin, to support our hypothesis, we first identified high-score putative binding sequences for CTCF/MBF-1 within the single sea urchin Hox gene cluster. Moreover, we observed the full evolu-tionary conservation of these binding sites in S. purpuratus and P. lividus species. Worth of men-tion, by chromatin immunoprecipitation (ChIP) assay, we detected the occupancy of MBF-1 on hox11/13-a, -b, and -c regulatory sequences at distinct stages of development. As expected from the binding of an activator, we found that the association of MBF-1 to the cis-regulatory sequences of both hox11/13-a and -b genes relates to the transcriptional status of these genes. Strikingly, we also mapped the physical binding of MBF-1 to hox11/13-c, which is instead not expressed during em-bryogenesis. Altogether, these observations indeed suggest the possibility that MBF-1, besides be-ing a transcription activator, could also function as a general chromatin organizer. To further support this hypothesis, we are planning ChIP-seq experiments to identify the association of MBF-1 to the sea urchin chromatin at a genome-wide level.
1. Di Caro, V. et al. (2007) J. Mol. Bio.,365, 1285-97.
2. Cavalieri,V et al. (2009) Nucleic Acid Res, 37,7407-7415.
3. Heger , P. et al. (2012) PNAS, 109, 17507\u201317512.
4. Cavalieri, V. et al. (2013) Plos Genetics, 9, e1003847
Precipitation products from the hydrology SAF
Abstract. The EUMETSAT Satellite Application Facility on Support to Operational Hydrology and Water Management (H-SAF) was established by the EUMETSAT Council on 3 July 2005, starting activity on 1 September 2005. The Italian Meteorological Service serves as Leading Entity on behalf of twelve European member countries. H-SAF products include precipitation, soil moisture and snow parameters. Some products are based only on satellite observations, while other products are based on the assimilation of satellite measurements/products into numerical models. In addition to product development and generation, H-SAF includes a product validation program and a hydrological validation program that are coordinated, respectively, by the Italian Department of Civil Protection and by the Polish Institute of Meteorology and Water Management. The National Center of Aeronautical Meteorology and Climatology (CNMCA) of the Italian Air Force is responsible for operational product generation and dissemination. In this paper we describe the H-SAF precipitation algorithms and products, which have been developed by the Italian Institute of Atmospheric Sciences and Climate (in collaboration with the international community) and by CNMCA during the Development Phase (DP, 2005–2010) and the first Continuous Development and Operations Phase (CDOP-1, 2010–2012). The precipitation products are based on passive microwave measurements obtained from radiometers onboard different sun-synchronous low-Earth-orbiting satellites (especially, the SSM/I and SSMIS radiometers onboard DMSP satellites and the AMSU-A + AMSU-B/MHS radiometer suites onboard EPS-MetOp and NOAA-POES satellites), as well as on combined infrared/passive microwave measurements in which the passive microwave precipitation estimates are used in conjunction with SEVIRI images from the geostationary MSG satellite. Moreover, the H-SAF product generation and dissemination chain and independent product validation activities are described. Also, the H-SAF program and its associated activities that currently are being carried out or are planned to be performed within the second CDOP phase (CDOP-2, 2012–2017) are presented in some detail. Insofar as CDOP-2 is concerned, it is emphasized that all algorithms and processing schemes will be improved and enhanced so as to extend them to satellites that will be operational within this decade – particularly the geostationary Meteosat Third Generation satellites and the low-Earth-orbiting Core Observatory of the international Global Precipitation Measurement mission. Finally, the role of H-SAF within the international science and operations community is explained.</p
The validation service of the hydrological SAF geostationary and polar satellite precipitation products
Abstract. The development phase (DP) of the EUMETSAT Satellite Application Facility for Support to Operational Hydrology and Water Management (H-SAF) led to the design and implementation of several precipitation products, after 5 yr (2005–2010) of activity. Presently, five precipitation estimation algorithms based on data from passive microwave and infrared sensors, on board geostationary and sun-synchronous platforms, function in operational mode at the H-SAF hosting institute to provide near real-time precipitation products at different spatial and temporal resolutions. In order to evaluate the precipitation product accuracy, a validation activity has been established since the beginning of the project. A Precipitation Product Validation Group (PPVG) works in parallel with the development of the estimation algorithms with two aims: to provide the algorithm developers with indications to refine algorithms and products, and to evaluate the error structure to be associated with the operational products. In this paper, the framework of the PPVG is presented: (a) the characteristics of the ground reference data available to H-SAF (i.e. radar and rain gauge networks), (b) the agreed upon validation strategy settled among the eight European countries participating in the PPVG, and (c) the steps of the validation procedures. The quality of the reference data is discussed, and the efforts for its improvement are outlined, with special emphasis on the definition of a ground radar quality map and on the implementation of a suitable rain gauge interpolation algorithm. The work done during the H-SAF development phase has led the PPVG to converge into a common validation procedure among the members, taking advantage of the experience acquired by each one of them in the validation of H-SAF products. The methodology is presented here, indicating the main steps of the validation procedure (ground data quality control, spatial interpolation, up-scaling of radar data vs. satellite grid, statistical score evaluation, case study analysis). Finally, an overview of the results is presented, focusing on the monthly statistical indicators, referred to the satellite product performances over different seasons and areas
DNA fragments binding CTCF in vitro and in vivo are capable of blocking enhancer activity
<p>Abstract</p> <p>Background</p> <p>Earlier we identified ten 100-300-bp long CTCF-binding DNA fragments selected earlier from a 1-Mb human chromosome 19 region. Here the positive-negative selection technique was used to check the ability of CTCF-binding human genomic fragments to block enhancer-promoter interaction when inserted into the genome.</p> <p>Results</p> <p>Ten CTCF-binding DNA fragments were inserted between the CMV enhancer and CMV minimal promoter driving the herpes simplex virus thymidine kinase (HSV<it>-tk</it>) gene in a vector expressing also the <it>neo</it><sup>R </sup>gene under a separate promoter. The constructs were then integrated into the genome of CHO cells, and the cells resistant to neomycin and ganciclovir (positive-negative selection) were picked up, and their DNAs were PCR analyzed to confirm the presence of the fragments between the enhancer and promoter in both orientations.</p> <p>Conclusions</p> <p>We demonstrated that all sequences identified by their CTCF binding both <it>in vitro </it>and <it>in vivo </it>had enhancer-blocking activity when inserted between the CMV minimal promoter and enhancer in stably transfected CHO cells.</p
A comprehensive overview of radioguided surgery using gamma detection probe technology
The concept of radioguided surgery, which was first developed some 60 years ago, involves the use of a radiation detection probe system for the intraoperative detection of radionuclides. The use of gamma detection probe technology in radioguided surgery has tremendously expanded and has evolved into what is now considered an established discipline within the practice of surgery, revolutionizing the surgical management of many malignancies, including breast cancer, melanoma, and colorectal cancer, as well as the surgical management of parathyroid disease. The impact of radioguided surgery on the surgical management of cancer patients includes providing vital and real-time information to the surgeon regarding the location and extent of disease, as well as regarding the assessment of surgical resection margins. Additionally, it has allowed the surgeon to minimize the surgical invasiveness of many diagnostic and therapeutic procedures, while still maintaining maximum benefit to the cancer patient. In the current review, we have attempted to comprehensively evaluate the history, technical aspects, and clinical applications of radioguided surgery using gamma detection probe technology
The effects of right temporoparietal junction stimulation on embodiment, presence, and performance in teleoperation
Embodiment (the sensation that arises when the properties of an external instrument are processed as if they are the attributes of one's own biological body) and (tele)presence (the sensation of being fully engaged and immersed in a location other than the physical space occupied by one's body) sustain the perception of the physical self and potentially improve performance in teleoperations (a system that enables human intelligence to control robots and requires implementing an effective human-machine interface). Embodiment and presence may be interdependent and influenced by right temporo-parietal junction (rTPJ) activity. We investigated the interplay between embodiment, (tele)presence, and performance in teleoperation, focusing on the role of the rTPJ. Participants underwent a virtual reality task with transcranial direct current stimulation (tDCS) twice, receiving either active or sham stimulation. Behavioral measures (driving inaccuracy, elapsed time in the lap, time spent in attentional lapses, short-term self-similarity, and long-term self-similarity), perceived workload (mental demand, physical demand, temporal demand, own performance, effort, and frustration), embodiment's components (ownership, agency, tactile sensations, location, and external appearance), and presence's components (realism, possibility to act, quality of interface, possibility to examine, self-evaluation of performance, haptic, and sounds) were assessed. The results showed that rTPJ stimulation decreased perceived ownership but enhanced presence with changes in the complexity of visuomotor adjustments (long and short-term self-similarity indices). Structural equation modeling revealed that embodiment increased visuomotor inaccuracy (a composite variable of overall performance, including deviations from the optimal trajectory and the time taken to complete the task), presence reduced workload, and workload increased inaccuracy. These results suggested a dissociation between embodiment and presence, with embodiment hindering performance. Prioritizing virtual integration may lower human performance, while reduced workload from presence could aid engagement. These findings emphasize the intricate interplay between rTPJ, subjective experiences, and performance in teleoperation
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