1,721,039 research outputs found
IL MONDO DEL LIBRO A LUCCA TRA XV E XVI SECOLO. PRODUZIONE, CIRCOLAZIONE E CONSERVAZIONE
No full textNel complesso panorama geopolitico dell’Europa moderna, Lucca rappresentò una realtà territoriale circoscritta e periferica, tendenzialmente pacifica e dedita ai commerci, che riuscì a conservare la propria indipendenza repubblicana fino al 1799. Le ricerche tentano di fornire un quadro ampio sul mondo del libro e la circolazione dei saperi nella città-Stato toscana tra XV e XVI secolo, riservando particolare attenzione alla produzione tipografica locale, di cui si ripercorrono le vicende storiche a partire dal duplice tentativo di introdurre la stampa da parte di Clemente da Padova (1472 e 1477), fra i primi stampatori di origine italiana, fino all’ascesa di Vincenzo Busdraghi (1548-1549), da più parti considerato il “principe degli stampatori lucchesi”. Di ciascuna edizione lucchese viene fornita una descrizione secondo i più recenti modelli di catalogazione bibliografica, sempre condotta su esemplari esaminati presso biblioteche e archivi, sia italiani che stranieri. La seconda sezione focalizza l’attenzione su alcuni episodi particolarmente significativi riguardanti la circolazione e il commercio librario, che interessò dapprima i codici manoscritti e poi i volumi a stampa, mettendo in evidenza i nomi di numerosi librai e cartolai attivi a Lucca e nelle zone limitrofe, emersi da inedite fonti notarili. Inoltre, viene proposta l’edizione dell’inventario post mortem della bottega pisana appartenuta al libraio Vincenzo Berretta, ma si considera anche la dispersione libraria attraverso l’analisi di maculature e frammenti, oltre alla circolazione di diversi prodotti editoriali, quali pronostici e messali, destinati a differenti categorie di lettori. Legata a doppio filo con le indagini sulle edizioni popolari di larga circolazione, la terza sezione offre un approfondimento sul Volto Santo, la taumaturgica reliquia conservata a Lucca nella Cattedrale di San Martino, di cui si analizza una serie di pubblicazioni quattro-cinquecentesche che riportano il racconto in prosa o in versi del leggendario arrivo in città. In ultimo, si propone una panoramica delle principali raccolte librarie presenti entro le mura lucchesi tra la seconda metà del Quattrocento e gli anni ’70 del secolo successivo, di cui è sopravvissuta una testimonianza coeva sotto forma di catalogo, inventario o lista di libri. Per l’eccezionale importanza nella storia delle biblioteche ecclesiastiche, viene fornito un elenco delle pubblicazioni a stampa appartenute al vescovo Felino Sandei, la cui raccolta si è conservata pressoché intatta dalla sua donazione al Capitolo della Cattedrale di Lucca nel 1503 fino ai nostri giorni.In the complex geopolitical landscape of Early Modern Europe, Lucca was a limited and peripheral reality, inclined to be peaceful and dedicated to trade, which succeeded in preserving its republican independence until 1799. The research attempts to provide a broad picture of the world of books and the circulation of knowledge in the Tuscan city-state between the XV and XVI centuries, focusing particular attention on local printing production, whose historical events are traced from the double attempt to introduce the printing press by Clemens Patavinus (1472 and 1477), among the first printers of Italian origin, to the rise of Vincenzo Busdraghi (1548-1549), widely considered “the prince of Lucca printers”. Each Lucchese edition is presented according to the latest models of bibliographic description, always conducted on specimens examined in Italian and foreign libraries and archives. The second section focuses the attention on some particularly significant episodes concerning the circulation and book trade, which first involved manuscripts and then printed volumes, highlighting the names of many booksellers and stationers active in Lucca and neighboring areas, which have emerged from unpublished notarial sources. In addition, the transcription of the posthumous inventory of the Pisan workshop belonging to the bookseller Vincenzo Berretta is proposed, but book dispersion is also considered through the analysis of some fragments and binding waste, as well as the circulation of different publishing products, such as forecasts and missals, intended for different categories of readers. Closely linked to the popular printing production, the third section offers an indepth look at the Holy Face of Lucca, the thaumaturgical relic preserved in Lucca in the Cathedral of San Martino, of which is analyzed a series of XVth and XVIth century editions which tell the story of its legendary arrival in the city in prose or verse. Finally, an overview of the main book collections present within the walls of Lucca between the second half of the fifteenth century and the 1570s is presented, of which a coeval record has survived in the form of a catalog, inventory or list of books. Because of its exceptional importance in the history of ecclesiastical libraries, is provided a list of the printed publications belonging to Bishop Felino Sandei, whose collection has been preserved almost complete since its donation to the Chapter of the Cathedral in 1503 to the present day
Vascular endothelial growth factor up-regulation in the mouse hippocampus and its role in the control of epileptiform activity
No full textThe vascular endothelial growth factor (VEGF) signalling pathway may represent an endogenous anti-convulsant in the rodent hippocampus although its exact contribution requires some clarification. In mouse hippocampal slices, the potassium channel blocker 4-aminopyridine (4-AP) in the absence of external Mg(2+)(0 Mg(2+)) produces both ictal and interictal activity followed by a prolonged period of repetitive interictal activity. In this model, we demonstrated that exogenous VEGF has clear effects on ictal and interictal activity as it reduces the duration of ictal-like events, but decreases the frequency and intensity of interictal discharges. VEGF affects epileptiform activity through its receptor VEGFR-2. We also demonstrated for the first time that the synaptic action of VEGF in the hippocampus is through VEGFR-2-mediated effects on NMDA and GABA(B) receptors and that VEGF does not affect the NMDA excytatory postsynaptic potential paired-pulse facilitation ratio. Exogenous VEGF does not affect the AMPA-mediated responses and the dendritic or the somatic GABA(A) inhibitory postsynaptic potentials. In addition, VEGF drastically reduces 0 Mg(2+)/4-AP-induced glutamate release through VEGFR-2 activation. In vitro epileptiform activity is sufficient to increase hippocampal expression of VEGF and VEGFR-2, and this up-regulation may serve a neuroprotective and/or anti-convulsant role. VEGFR-2 up-regulation has been localized to the CA1 region, which suggests that VEGF signalling may protect CA1 pyramidal cells from hyperexcitability. These results indicate that VEGF controls epileptic activity by influencing both glutamatergic and GABAergic transmission and further advance our understanding of the conditions required for endogenous VEGF up-regulation, and the mechanisms by which VEGF achieves an anti-convulsant effect
BERBERINE, A NATURAL ALKALOID, AFFECTS ZEBRAFISH CARDIOVASCULAR DEVELOPMENT
No full textThe zebrafish larva is increasingly used as a vertebrate animal model for in vivo drug discovery and for toxicology and biosafety assessments, bridging the gap between cell assays and rodent assays. In fact, zebrafish responses to toxic compounds are highly predictive of mammalian responses because of their very similar physiology, development and molecular pathways. In this study we aim at testing the potential toxicity and teratogenity of berberine, a natural alkaloid displaying a variety of therapeutical properties, whose effects on embryo development have been poorly characterized. We determined the LC50 value as 213 mg/L ± 8,30 and 156 mg/L ± 4,965 after 72 hrs and 96 hrs of treatment, respectively. We then analysed the effects observed at a concentration of 100 mg/L. In particular, we focused on cardiovascular development, which we found to be affected in a concentration and time dependent manner by berberine treatment. Treated embryos display cardiac defects, with a critical treatment window from 48hpf to 72hpf. Morphological analysis performed with heart specific markers shows the presence of defects in cardiac looping, while valves morphogenesis does not appear to be perturbed. We are currently further analyzing the cardiac defects as well as evaluating vascular alterations in pigmentless zebrafish larvae specifically expressing GFP in endothelial cells (casper/kdrl:GFP)
Antiangiogenic role of miR-361 in human umbilical vein endothelial cells: functional interaction with the peptide somatostatin
No full textSomatostatin (SRIF) acts as antiangiogenic factor, but its role in the regulation of microRNAs (miRNAs) targeting proangiogenic factors is unknown. We used human umbilical vein endothelial cells (HUVEC) to investigate whether i. miRNAs targeting proangiogenic factors are influenced by hypoxia, ii. their expression is regulated by SRIF and iii. SRIF-regulated miRNAs affect HUVEC angiogenic phenotype. The involvement of signal transducer and activator of transcription (STAT) 3 and hypoxia inducible factor (HIF)-1 in miRNA effects was studied. Quantitative real-time PCR, Western blot, cell proliferation assays and ELISA were used. Using specific algorithms, three miRNAS (miR-17, miR-18b and miR-361) were predicted to bind angiogenesis-associated factors including STAT3, HIF-1α and vascular endothelial growth factor (VEGF). Hypoxia downregulated miR-17 and miR-361 without affecting miR-18b. SRIF restored decreased levels of miR-361 acting at the SRIF receptor sst1. Downregulated miR-361 was also restored by HIF-1α inhibition with YC-1. Combined application of SRIF did not influence YC-1-induced miR-361 downregulation suggesting that YC-1 and SRIF modulate miR-361 through a common mechanism involving HIF-1α. This possibility was confirmed by the result that HIF-1α activation in normoxia downregulated miR-361 and that this downregulation was prevented by SRIF. miR-361 overexpression reduced hypoxia-induced cell proliferation and VEGF release indicating miR-361 involvement in the acquisition of an angiogenic phenotype by HUVEC. miR-361 effects on VEGF were enhanced by the co-administration of SRIF. Our results suggest that i. SRIF regulates miR-361 expression through a control on HIF-1, ii. miR-361 affects HUVEC angiogenic phenotype and iii. SRIF and miR-361 act cooperatively in limiting hypoxia-induced VEGF release
Functional effects of somatostatin receptor 1 activation on synaptic transmission in the mouse hippocampus
No full textSomatostatin-14 (SRIF) co-localizes with GABA in the hippocampus and regulates neuronal excitability. A role of SRIF in the control of hippocampal activity has been proposed, although the exact contribution of each SRIF receptor (sst1–sst5) in mediating SRIF action requires some clarification. We used hippocampal slices of wild-type and sst1 knockout (KO) mice and selective pharmacological tools to provide conclusive evidence for a role of sst1 in mediating SRIF inhibition of synaptic transmission. With single- and double-label immunohistochemistry, we determined the distribution of sst1 in hippocampal slices and we quantified sst1 colocalization with SRIF. With electrophysiology, we found that sst1 activation with CH-275 inhibited both the NMDA- and the a-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-mediated responses. Results from sst1 KO slices confirmed the specificity of CH-275 effects; sst1 activation did not affect the inhibitory transmission which was in contrast increased by sst4 activation with L-803,087 in both wild-type and sst1 KO slices. The AMPA-mediated responses were increased by L-803,087. Functional interaction between sst1 and sst4 is suggested by the finding that their combined activation prevented the CH-275-induced inhibition of AMPA transmission. The involvement of pre-synaptic mechanisms in mediating inhibitory effects of sst1 on excitatory transmission was demonstrated by the finding that CH-275 (i) increased the paired-pulse facilitation ratio, (ii) did not influence the AMPA depolarization in the presence of tetrodotoxin, and (iii) inhibited glutamate release induced by epileptiform treatment. We conclude that SRIF control of excitatory transmission through an action at sst1 may represent an important contribution to the regulation of hippocampal activity
Exposure to the natural alkaloid Berberine affects cardiovascular system morphogenesis and functionality during zebrafish development
Full text linkThe plant-derived natural alkaloid berberine displays therapeutic potential to treat several pathological conditions, including dyslipidemias, diabetes and cardiovascular disorders. However, data on berberine effects during embryonic development are scarce and in part controversial. In this study, using zebrafish embryos as vertebrate experimental model, we address the effects of berberine treatment on cardiovascular system development and functionality. Starting from the observation that berberine induces developmental toxicity and pericardial edema in a time- and concentration-dependent manner, we found that treated embryos display cardiac looping defects and, at later stages, present an abnormal heart characterized by a stretched morphology and atrial endocardial/myocardial detachment. Furthermore, berberine affected cardiac functionality of the embryos, promoting bradycardia and reducing the cardiac output, the atrial shortening fraction percentage and the atrial stroke volume. We also found that, during development, berberine interferes with the angiogenic process, without altering vascular permeability. These alterations are associated with increased levels of vascular endothelial growth factor aa (vegfaa) mRNA, suggesting an important role for Vegfaa as mediator of berberine-induced cardiovascular defects. Altogether, these data indicate that berberine treatment during vertebrate development leads to an impairment of cardiovascular system morphogenesis and functionality, suggesting a note of caution in its use during pregnancy and lactation
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
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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