1,721,129 research outputs found
Aged PrP null mice show defective processing of neuregulins in the peripheral nervous system
No full textA prion, a protease-resistant conformer of the cellular prion protein (PrP(C)), is the causative agent of transmissible spongiform encephalopathies or prion diseases. While this property is well established for the aberrantly folded protein, the physiological function of PrP(C) remains elusive. Among different putative functions, the non-pathogenic protein isoform PrP(C) is involved in several cellular processes. Here, we show that PrP(C) regulates the cleavage of neuregulin-1 proteins (NRG1). Neuregulins provide key axonal signals that regulate several processes, including glial cells proliferation, survival and myelination. Interestingly, mice devoid of PrP(C) (Prnp0/0) were recently shown to have a late-onset demyelinating disease in the peripheral nervous system (PNS) but not in the central nervous system (CNS). We found that NRG1 processing is developmentally regulated in the PNS and, by comparing wildtype and Prnp0/0 mice, that PrP(C) influences NRG1 processing in old, but not in young, animals. In addition, we found that also the processing of neuregulin-3, another neuregulin family member, is altered in the PNS of Prnp0/0 mice. These differences in neuregulin proteins processing are not paralleled in the CNS, thus suggesting a different cellular function for PrP(C) between the CNS and the PN
Comparison of proton and electron radiation effects on dark count rate in a CMOS SPAD sensor
No full textThe aim of this work is to investigate the degradation induced by radiation on the Dark Count Rate in a monolithic SPADs detector manufactured in a 150-nm CMOS process. Two irradiation campaigns have been carried out with 16 MeV protons and 2 MeV electrons. Samples have been exposed to different displacement damage dose. Differences between the effects induced by the two irradiation particle types have been observed. The Dark Count Rate characterization as a function of the delivered fluence has been reported, providing the limits of operability of such devices in a radiation environment. Finally, possible Dark Count Rate mitigation techniques have been investigated
Highly Sensitive Piezoelectric Ceramic Nanofibers for Flexible Transducers and Advanced Applications
Full text linkPolymeric piezoelectric materials have attracted enormous success in the field of wearable electronics due to their high flexibility and good mechanical stability. Nonetheless, these materials exhibit a low piezoelectric response if compared to ceramics. This study is focused on the development of a flexible and highly sensitive piezoelectric sensor made with ceramic lead zirconate titanate (PZT) nanofibers. Results show an exceptionally high sensitivity of 30 mV/N and a piezoelectric strain coefficient d33 of 39 pC/N for the fabricated PZT sensor
Regio VII (Etruria)
No full textPartendo dall’opera fondamentale del Kubitschek si analizzano le attestazioni di tribù contenute in epigrafi provenienti dalle città dell’Etruria romana, venute in luce dopo la pubblicazione del lavoro dello studioso tedesco, al fine di stabilire quale fosse la tribù prevalente in ogni singolo centro.
Vengono confermate le ascrizioni tribali indicate dal Kubitschek, tranne che per alcuni centri dell’Etruria meridionale, fra i quali Alsium, Caere, Castrum Novum, Forum Clodii, da attribuire alla Voltinia tribus, sulla base degli studi compiuti da Lidio Gasperini, nonché per Rusellae (Arnensis) e Populonium (Galeria), sulla base di iscrizioni rinvenute negli ultimi decenni
Gene expression profiling to identify druggable targets in prion diseases
No full textImportance of the field: Despite many recent advances in prion research, the
molecular mechanisms by which prions cause neurodegeneration have not
been established. In fact, the complexity and the novelty characterizing this
class of disorders pose a huge challenge to drug discovery. Pharmacogenomics
has recently adopted high-throughput transcriptome analyses to predict
potential drug target candidates, with promising results in various fields
of medicine.
Areas covered in this review: The present work offers an overview of the
transcriptional alterations induced by prion infection in different biological
systems. Hereafter, therapeutic approaches are discussed in light of the
identified altered processes.
What the reader will gain: This review offers readers a detailed overview on
microarray analyses, taking into account their advantages and limitations.
Our work can help readers, from many research areas, to design a suitable
microarray experiment.
Take home message: So far, drugs acting on the pathways identified by
microarray analysis have not been found to be effective in prion diseases
therapy. An integration of gene expression profiling, proteomics and
physiology should be applied to pursue this aim
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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