345 research outputs found
E1-Ngn2/Cre is a new line for regional activation of Cre recombinase in the developing CNS
No full textWe generated a transgenic mouse line named
E1-Ngn2/Cre that expresses Cre recombinase and GFP
under the control of the E1 enhancer element of the gene
Ngn2 (Scardigli et al.: Neuron 31:203–217, 2001). Crerecombinase activity and GFP fluorescence are consistent
with the reported expression pattern controlled by
the E1-Ngn2 enhancer. Recombination was detected in
the progenitor domains p1 and p2 in the ventricular zone
of the neural tube and in distinct domains of the pretectum,
the dorsal and ventral thalamus, the tegmentum of
the mesencephalon, and the hindbrain. In the developing
cortex, Cre-recombinase activity is confined to a subpopulation
of progenitors predominantly in the region of
the ventral and lateral pallium. The E1-Ngn2/Cre mouse
line thus provides an excellent novel tool for a regionspecific
conditional mutagenesis in the developing CNS
Correction to: Size‐Dependent Enforcement, Tax Evasion and Dimensional Trap
No full textThe article “Size‐Dependent Enforcement, Tax Evasion and Dimensional Trap”, written by Raffaella Coppier, Elisabetta Michetti and Luisa Scaccia, was originally published electronically on the publisher’s internet portal on 05 July 2023 without open access. With the author(s)’ decision to opt for Open Choice the copyright of the article changed on 24 February 2024 to © The Author(s) 2024 and the article is forthwith distributed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made
RISC activity in hippocampus is essential for contextual memory
No full textRNA-Induced Silencing Complex (RISC) mediates post-transcriptional control of gene expression and
contains Argonaute 2 (AGO2) protein as a central effector of cleavage or inhibition of mRNA translation.
In the brain, the RISC pathway is involved in neuronal functions, such as synaptic development and local
protein synthesis, which are potentially critical for memory. In this study, we examined the role of RISC
in memory formation in rodents, by silencing AGO2 expression in dorsal hippocampus of C57BL/6 mice
and submitting animals to hippocampus-related tasks. One week after surgery, AGO2 downregulation
impaired both short-term and long-term contextual fear memories. Conversely, no long-lasting effects
were observed three weeks after surgery, when AGO2 levels were re-established. These results show that
altered RISC activity severely affects learning and memory processes in rodents
ProNGF Is a Cell-Type-Specific Mitogen for Adult Hippocampal and for Induced Neural Stem Cells
No full textThe role of proNGF, the precursor of nerve growth factor (NGF), in the biology of adult neural stem cells (aNSCs) is still unclear. Here, we analyzed adult hippocampal neurogenesis in AD11 transgenic mice, in which the constitutive expression of anti-NGF antibody leads to an imbalance of proNGF over mature NGF. We found increased proliferation of progenitors but a reduced neurogenesis in the AD11 dentate gyrus (DG)-hippocampus (HP). Also in vitro, AD11 hippocampal neural stem cells (NSCs) proliferated more, but were unable to differentiate into morphologically mature neurons. By treating wild-type hippocampal progenitors with the uncleavable form of proNGF (proNGF-KR), we demonstrated that proNGF acts as mitogen on aNSCs at low concentration. The mitogenic effect of proNGF was specifically addressed to the radial glia-like (RGL) stem cells through the induction of cyclin D1 expression. These cells express high levels of p75(NTR), as demonstrated by immunofluorescence analyses performed ex vivo on RGL cells isolated from freshly dissociated HP-DG or selected in vitro from NSCs by leukemia inhibitory factor. Clonogenic assay performed in the absence of mitogens showed that RGLs respond to proNGF-KR by reactivating their proliferation and thus leading to neurospheres formation. The mitogenic effect of proNGF was further exploited in the expansion of mouse-induced neural stem cells (iNSCs). Chronic exposure of iNSCs to proNGF-KR increased their proliferation. Altogether, we demonstrated that proNGF acts as mitogen on hippocampal and iNSCs. Stem Cells 2019;37:1223-123
Impaired spatio-temporal coordination of subventricular neurogenesis is restored by physical exercise
No full textA major aim of neural stem cells field is to harness endogenous neurogenesis to replace neurons damaged as a consequence of brain damage and neurodegeneration. Olfactory interneurons arise throughout life from neural stem cells residing in the subventricular zone (SVZ) of the lateral ventricle. Post mitotic neuroblast then migrate along the rostral migratory stream (RMS) to the olfactory bulb where undergone to fully maturation and functional integration in the olfactory circuitry. To ensure a continuous source of newly-generated adult interneurons, stem and progenitor cell proliferation, neuroblast migration, and terminal differentiation must be tightly coordinated. In this study we analyzed the effect of physical exercise in orchestrating the different steps of subventricular neurogenesis in a mouse lacking the antiproliferative gene Btg1 which displays an impaired subventricular neurogenesis. As previously demonstrated Btg1 loss-of-function mice exhibit a strong reduction of proliferation associated with a premature exit from the cell cycle and an anticipated migration toward the olfactory bulb where the neuroblast fail to fully differentiate and consequently to be specifically recruited in olfactory-dependent memory circuitry.
In the study we demonstrate that running fully reverses the profound reduction of proliferation within the SVZ of the lateral ventricle in the Btg1-deficient mice, mainly through a recruitment and expansion of the quiescent neural stem cells (NSCs) . Moreover, cell cycle analysis reveals that 12 days of running induces a shortening of the S-phase and consequently of the whole cell cycle length in both neural stem (GFAP+, type C) and progenitor (DCX+, type A) cells of Btg1 knockout mice, allowing the restoring of a proper coordination between the cell cycle exit and the initial phase of post-mitotic neuroblasts migration. These events result in a increased rate of terminal maturation and integration in the olfactory- dependent memory circuits. Finally, as previously stated by others, we does not detect any beneficial effect of running in the subventricular zone wild type mice . All together these in vivo data suggest that a) the quiescent state of neural stem cells lacking the cell cycle inhibitory control can be reactivated by running; b) the cell cycle kinetics in the adult SVZ plays a pivotal role not only for proliferation but also for the tight coordination of cell cycle exit, migration and terminal differentiation.
In vitro analysis demonstrates that running induces a great expansion of primary neurospheres isolated by Btg1 ko subvrenticular zone, supporting the in vivo observation about the increase of neural stem pool in this neurogenic niche. However the running-dependent hyperproliferation of the neural stem cells leads to a rapid depletion of the stem cell pool and /or to its ability to further expand in vitro. This fact suggest that the effect of running on the Btg1 knock out neural stem cell proliferation is not cell-autonomous but strictly dependent on niche environment. We can hypothesized that the presence of still unknown factors triggered by physical activity in the subventricular niche promotes and maintains in vivo the hyperproliferative state of neural stem cells in the Btg1 knockout mice
A spatial cross-sectional analysis of political trends in Italian municipalities
No full textThe aim of this paper is to detect mimicking behaviour in the tax setting of local governments which share similar political ideology. We conduct an empirical investigation of municipalities' cross-sectional data of the Marche region using spatial econometrics models. Discriminating between several sources of fiscal interaction, empirical evidence suggests that municipalities governed by the same coalition tend to implement similar tax rates according to their ideology. Copyright (c) 2008 the author(s). Journal compilation (c) 2008 RSAI.
Pendenza anomala di processi arbitrali ed estinzione del processo per inattività delle parti
No full textThe Author analyes two italian judgments concerning both arbitral proceedings pending for a long time without any activit
“Noi abbiamo visto tante città, abbiamo un’altra cultura”. Servizio domestico, migrazioni e identità di genere in Italia: uno sguardo di lungo periodo
No full textAbstract
The article aims to show both long-term continuities and the transformation of domestic service in Italy during the 19th and 20th century. Firstly, the article shows that, today, domestic workers are possibly more numerous than a century ago, and it explains why Italian families seek private solutions (such as hiring a domestic worker) to the problem of reconciling reproductive and productive labour. The gap between "rich" and "poor" countries as well as Italian migration policy make this choice possible, because they make working in Italy as a domestic worker "attractive" for many migrants and employing a foreigner advantageous for Italian families. A further consequence is that there are a considerable number of men among migrant domestic workers: their arrival has contributed to a certain "re-masculinisation" of domestic personnel. The reasons for the feminisation of domestic service in the 19th and 20th centuries are analysed in the second and third section of the paper, where the author also considers the policies developed by servants' associations, the Catholic church and the Italian state. The author investigates the role of demographic and economic factors in stimulating migration and then focuses on two cases characterised by a growing imbalance between rural and urban areas, i.e., the province of Bologna in the 19th century and Italy during the fascist era. The author concludes by noting that domestic service (paradoxically) represented a way for many women to escape misery and become more independent
Delegitimization and US presidential electoral campaigns, 1896-1980
No full textThe essay focuses on delegitimization of one’s political opponent as a discursive strategy in US political elections from 1896 to 1980. Starting with a definition of delegitimization as a means of contesting the legitimacy of the opponent’s aspiration to power by turning him/her into an enemy outside the constitutional perimeter, the author highlights the circumstances that conduced to political delegitimization tactics in US presidential campaigns, as well as the stock themes in use over the various periods
Cooperare nella scuola per costruire comunità. Dimensioni organizzative e culturali, metodologie e strategie operative
No full textThis PhD thesis intends to clear whether and on what conditions a "community school " is possible nowadays.
In the firsts chapter we mainly tried to reconsider and re-define the Community construct, remarking an often overworked use and a polisemantic nature and ambiguity of this word, mainly used as a metaphor than as an analytical concept, due to its various meanings and its ambiguity .
In particular we tried to recover the analysis which, beginning from the end of the 19 th century, was made by some sociologists, to continue up to our time with the present-day debates, which have seen opposition between the liberals and the communitarians positions, especially in the Anglo-Saxon world. While some late eighteenth century have thought of the Community as a stage in the process of the social change showing dominations of the society on the Community, highlighting an evolution of the dicothomes coyle other authors, mainly in more recent times, have pointed out an inherent tendency of the two ideal types to coexist and mix, thinking that the coexistence of community life next to forms of society life is possible.
In the second chapter we tried to underline the educational value of the Community, pointing out, in particular, that the Community value is achieved in educational particularity when the community acts knowingly and intentionally in the training of persons living inside it. First we tried to outline the attempts made in Italy to create an authentic Community school, from the delegates decrees (after the 1968 crisis and the Faure Report) to the school of autonomy of our times (2000). Then, in order to realize a comparison on an international ground, we examined in USA in particular to the experiences of Community school followed and documented by Thomas Sergiovanni, in San Antonio (Texas), in collaboration with the Trinity University. Those experiences, and even more the above-mentioned author, have become the main reference of our study, both from point of view of a the theoretic reflection and from an operating point of view .
In the third chapter we pointed out the pedagogical, methodological and educational choices which are the most consistent with the model and the more suitable for the development of the organizing and cultural dimensions according to which a community school may be declined. A special attention has been paid to the cooperative methods that we considered particularly consistent for organisation in the school activity, in students groups and teachers groups.
In the last chapter we described the experience held with the Childhood Centres of the Cooperative "Insieme Si Può" connected to Foundation "Ispirazione", promoter and supporter of the project. In particular, the aim of the intervention (developed according to the action research approach) was to test some operative instruments to verify, even if empirically, the functionality in order to promote the dimensions according to which the community school is organized. Being aware to undertake a path that couldn’t bring to definite goal, that is to the creation of an authentic community school, we went on considering that goal as an ideal rule toward which to go with which to compare the reality. As regards that goal we tried to give a little contribution to the study of the of the necessary features for a possible project hypothesis.La presente tesi di dottorato si è proposta di chiarire se e a quali condizioni è possibile oggi una “scuola comunità”.
Nel primo capitolo si cerca di fare chiarezza attorno al costrutto di comunità rilevando, a tal proposito, un uso spesso inflazionato e una polisemanticità e ambiguità del termine, spesso usato più come metafora che come concetto analitico. In particolare si è cercato di recuperare l’analisi che, a partire dalla fine del diciannovesimo secolo, è stata realizzata da alcuni sociologi, per proseguire fino ai giorni nostri con i dibattiti contemporanei che hanno visto contrapporsi fra loro le posizioni, soprattutto nel mondo anglosassone, dei liberals e dei communitarians. Se alcuni autori di fine Ottocento hanno pensato alla comunità come ad una tappa del processo di social change che vede l’affermarsi della società sulla comunità evidenziando un carattere evolutivo della coppia dicotomica, altri, soprattutto in tempi più recenti, hanno evidenziato una tendenza intrinseca dei due ideal tipi a coesistere e mescolarsi, ritenendo possibile la coesistenza di vita comunitaria accanto a forme di vita societaria.
Nel secondo capitolo si è tentato di cogliere la valenza pedagogica della comunità, rilevando, in particolare, che il valore comunitario si realizza nella sua peculiarità educativa quando la comunità agisce consapevolmente e intenzionalmente per la formazione delle persone che in essa vivono. Da una parte si è cercato di delineare i tentativi, fatti in Italia, dai Decreti Delegati (dopo la crisi del ’68 e il Rapporto Faure) alla scuola dell’autonomia dei giorni nostri (2000), per la creazione di una comunità scolastica autentica. Dall’altra, allo scopo di realizzare un confronto sul piano internazionale, si è guardato agli Stati Uniti e in particolare alle esperienze di community school seguite e documentate da Thomas Sergiovanni, a San Antonio in Texas in collaborazione con la Trinity University. Tali esperienze, e più ancora tale autore, sono divenuti il riferimento principale del percorso, sia dal punto di vista della riflessione teorica che dal punto di vista operativo.
Nel terzo capitolo sono state messe in rilievo le scelte pedagogiche, metodologiche e didattiche più coerenti con il modello e più adatte allo sviluppo delle dimensioni organizzative e culturali, in cui una scuola comunità può essere declinata. Un particolare approfondimento è stato fatto all’interno del capitolo in merito ai metodi cooperativi ritenuti particolarmente coerenti per l’organizzazione dell’attività in classe e nella scuola, nei gruppi studenti e nei gruppi docenti.
Nell’ultimo capitolo si è descritto l’intervento sul campo che è stato realizzato con i Centri Infanzia della Cooperativa “Insieme Si Può” ,collegata a Fondazione “Ispirazione”, ente promotore e sostenitore del progetto. In particolare, l’obiettivo dell’intervento (sviluppato secondo la metodologia della ricerca azione action research) è stato quello di testare alcuni strumenti operativi per verificarne, anche se in modo empirico, la funzionalità ai fini della promozione delle dimensioni in cui la scuola comunità si declina. Nella consapevolezza di intraprendere un percorso che non poteva portare ad una meta definitiva, e cioè alla creazione di un’autentica scuola comunità si è proceduto considerando tale meta come un ideale regolativo verso cui muovere e con cui comparare la realtà. Rispetto a questa meta si è cercato di dare un piccolo contributo per lo studio delle caratteristiche necessarie ad una possibile ipotesi progettuale
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