26 research outputs found
Down-regulation of the Lamin A/C in neuroblastoma triggers the expansion of tumor initiating cells
Tumor-initiating cells constitute a population within a tumor mass that shares properties with normal stem cells and is considered responsible for therapy failure in many cancers. We have previously demonstrated that knockdown of the nuclear envelope component Lamin A/C in human neuroblastoma cells inhibits retinoic acid-mediated differentiation and results in a more aggressive phenotype. In addition, Lamin A/C is often lost in advanced tumors and changes in the nuclear envelope composition occur during tumor progression. Based on our previous data and considering that Lamin A/C is expressed in differentiated tissues, we hypothesize that the lack of Lamin A/C could predispose cells toward a stem-like phenotype, thus influencing the development of tumor-initiating cells in neuroblastoma. This paper demonstrates that knockdown of Lamin A/C triggers the development of a tumor-initiating cell population with self-renewing features in human neuroblastoma cells. We also demonstrates that the development of TICs is due to an increased expression of MYCN gene and that in neuroblastoma exists an inverse relationship between LMNA and MYCN expression
La scuola che funziona. Indagine sulle caratteristiche organizzative e didattiche in istituti con effetto-scuola positivo e negativo
Microglia promote glioblastoma via mTOR-mediated immunosuppression of the tumour microenvironment
Tumour-associated microglia/macrophages (TAM) are the most numerous non-neoplastic populations in the tumour microenvironment in glioblastoma multiforme (GBM), the most common malignant brain tumour in adulthood. The mTOR pathway, an important regulator of cell survival/proliferation, is upregulated in GBM, but little is known about the potential role of this pathway in TAM. Here, we show that GBM-initiating cells induce mTOR signalling in the microglia but not bone marrow-derived macrophages in both in vitro and in vivo GBM mouse models. mTOR-dependent regulation of STAT3 and NF-κB activity promotes an immunosuppressive microglial phenotype. This hinders effector T-cell infiltration, proliferation and immune reactivity, thereby contributing to tumour immune evasion and promoting tumour growth in mouse models. The translational value of our results is demonstrated in whole transcriptome datasets of human GBM and in a novel in vitro model, whereby expanded-potential stem cells (EPSC)-derived microglia-like cells are conditioned by syngeneic patient-derived GBM-initiating cells. These results raise the possibility that microglia could be the primary target of mTOR inhibition, rather than the intrinsic tumour cells in GBM
Synthesis and evaluation of new Hsp90 inhibitors based on a 1,4,5-trisubstituted 1,2,3-triazole scaffold
Abstract: Ruthenium catalyzed 1,3-cycloaddition (click chemistry) of an azido moiety installed on dihydroxycumene scaffold with differently substituted aryl propiolates, gave a new family of 1,4,5-trisubstitued triazole carboxylic acid derivatives that showed high affinity towards Hsp90 associated with cell proliferation inhibition, both in nanomolar range. The 1,5 arrangement of the resorcinol, the aryl moieties, and the presence of an alkyl (secondary) amide in position 4 of the triazole ring, were essential to get high activity. Docking simulations suggested that the triazoles penetrate the Hsp90 ATP binding site. Some 1,4,5-trisubstitued triazole carboxamides induced dramatic depletion of the examined client proteins and a very strong increase in the expression levels of the chaperone Hsp70. In vitro metabolic stability and in vivo preliminary studies on selected compounds have shown promising results comparable to the potent Hsp90 inhibitor NVP-AUY922. One of them, (compound 18; SST0287CL1) was selected for further investigation as the most promising drug candidate
Nano-Crystalline &Amorphous Silicon PhotoTransistor Performance Analysis
In this thesis, we compared electrical performance and stability of a novel nanocrystalline Si (nc-Si) thin film phototransistor (TFT) phototransistor and a regular amorphous silicon (a-Si:H) TFT phototransistor for large area imaging applications. The electrical performance parameters of nc-Si TFT phototransistor were extracted from the electrical (current-voltage) testing in dark and under illumination. The field-effect mobility is found to be around 1.2 cm2V-1s-1, the threshold voltage around 3.9V and the sub-threshold voltage slope around 0.47V/Dec. Optical properties of nc-Si TFT phototransistor have been evaluated under the green light illumination in the range of 1014 – 1017 lum, and the photocurrent gain and the external quantum efficiency were extracted from the experimental results. By comparing the results with those for a-Si:H TFTs measured under the same conditions, we found that nc-Si TFT has higher photo current gain under low illumination intensity, 5 ×1014 to 7 ×1015 lum. This thesis shows the relations bewteen the photo current gain, the external quantum efficiency, TFT drain and TFT gate bias; the photo current gain and the external quantum efficiency can be controlled by the Vds and the Vgs
La scuola che funziona. Indagine sulle caratteristiche organizzative e didattiche in istituti con effetto-scuola positivo e negativo.
Nello studio dell\u2019efficacia scolastica i modelli teorici di riferimento suggeriscono l\u2019importanza di utilizzare approcci multifattoriali. In questo studio sono stati considerati fattori riconducibili ai processi organizzativi e didattici, con l\u2019obiettivo di indagare differenze tra istituti con effetto-scuola (elaborato da Invalsi) positivo e negativo. Sono stati coinvolti 1774 insegnanti provenienti da 73 scuole di tre regioni italiane, i quali hanno compilato un questionario on-line. I risultati di confronto tra istituti con livelli positivi versus negativi di effetto-scuola hanno evidenziato alcune differenze. In particolare, le scuole con risultati di apprendimento migliori mostrano livelli significativamente pi\uf9 alti di leadership di supporto del dirigente scolastico e di decision-making partecipativo. I risultati e le proposte di intervento vengono discussi utilizzando un approccio multifattoriale e interdisciplinareTheoretical models suggest multifactorial approaches for the investigation of school effectiveness. Therefo-re, in this study factors related to organizational and educational processes have been considered, with the aim of investigating differences between institutions with positive versus negative added value (developed by Invalsi). The study involved 1174 teachers, employed in 73 schools in three different Italian regions, who filled in an on-line questionnaire. The comparison between schools with a positive versus negative added value showed some differences. Particularly, schools with more positive learning outcomes showed significantly higher levels of supportive leadership and a participative decision-making style. Results and intervention pro-posals are discussed using a multifactorial and interdisciplinary approach
Effectiveness of an Educational Filmmaking Project in Promoting the Psychological Well-Being of Adolescents with Emotive/Behavioural Problems
Evidence suggests that adolescents respond positively to simple, early interventions, including psychosocial support and educational interventions, even when offered in non-clinical settings. Cinematherapy can help manage life challenges, develop new skills, increase awareness, and offer new ways of thinking about specific problems. This pilot trial was conducted in Italy, aiming to investigate the effects of a six-week filmmaking course on the psychological well-being of adolescents (N = 52) with emotional/behavioural problems and neurodevelopmental disorders. At the end of the project, most participants showed improvements mostly in social skills, such as social cognition (p = 0.049), communication (p = 0.009), and motivation (p = 0.03), detected using the SRS Social Responsiveness Scale. In addition, social awareness (p = 0.001) increased in all patients. Statistically significant differences resulted in four sub-scales of Youth Self-Report Scale: withdrawn/depressed (p = 0.007), social problems (p = 0.003), thought problems (p p = 0.03); these results showed a decrease in emotional and behavioural problems. This study is an innovative therapeutic and educational approach based on the filmmaking art. This research can offer an empirical basis for the effectiveness of alternative therapeutic tools in child and adolescent psychiatric disorders. At the same time, it can be replicated in broader contexts (e.g., school and communities) to promote children’s psychological well-being
Confocal Analysis of Nuclear Lamina Behavior during Male Meiosis and Spermatogenesis in <i>Drosophila melanogaster</i>
<div><p>Lamin family proteins are structural components of a filamentous framework, the nuclear lamina (NL), underlying the inner membrane of nuclear envelope. The NL not only plays a role in nucleus mechanical support and nuclear shaping, but is also involved in many cellular processes including DNA replication, gene expression and chromatin positioning. Spermatogenesis is a very complex differentiation process in which each stage is characterized by nuclear architecture dramatic changes, from the early mitotic stage to the sperm differentiation final stage. Nevertheless, very few data are present in the literature on the NL behavior during this process. Here we show the first and complete description of NL behavior during meiosis and spermatogenesis in <i>Drosophila melanogaster</i>. By confocal imaging, we characterized the NL modifications from mitotic stages, through meiotic divisions to sperm differentiation with an anti-laminDm0 antibody against the major component of the <i>Drosophila</i> NL. We observed that continuous changes in the NL structure occurred in parallel with chromatin reorganization throughout the whole process and that meiotic divisions occurred in a closed context. Finally, we analyzed NL in <i>solofuso</i> meiotic mutant, where chromatin segregation is severely affected, and found the strict correlation between the presence of chromatin and that of NL.</p></div