196 research outputs found

    Francesca da Rimini : un libretto di Felice Romani, tra Dante e Mazzini

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    Analizzando tre testi di autori teatrali italiani a cavallo tra XVIII e XIX secolo, che scelsero la tragedia di Paolo e Francesca come dramma di prosa, si indagheranno in questo studio le modifiche che porteranno alla scrittura, ad opera di Felice Romani, di uno dei suoi libretti meno famosi: Francesca da RiminiThrough an analysis of three texts by Italian playwrights at the turn of the eighteenth and nineteenth century, who chose the tragedy of Paolo and Francesca as a prose drama, this article will study the adaptations in the writing of one of Felice Romani's lesser-known librettos: Francesca da Rimini

    Enhanced rate of degradation of basic proteins by 26S immunoproteasomes.

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    AbstractImmunoproteasomes are alternative forms of proteasomes specialized in the generation of MHC class I antigenic peptides and important for efficient cytokine production. We have identified a new biochemical property of 26S immunoproteasomes, namely the ability to hydrolyze basic proteins at greatly increased rates compared to constitutive proteasomes. This enhanced degradative capacity is specific for basic polypeptides, since substrates with a lower content in lysine and arginine residues are hydrolyzed at comparable rates by constitutive and immunoproteasomes. Crucially, selective inhibition of the immunoproteasome tryptic subunit β2i strongly reduces degradation of basic proteins. Therefore, our data demonstrate the rate limiting function of the proteasomal trypsin-like activity in controlling turnover rates of basic protein substrates and suggest new biological roles for immunoproteasomes in maintaining cellular homeostasis by rapidly removing a potentially harmful excess of free histones that can build up under different pathophysiological conditions

    Enhanced Expression of Interferon-γ-Induced Antigen-Processing Machinery Components in a Spontaneously Occurring Cancer

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    AbstractIn human tumors, changes in the surface expression and/or function of major histocompatibility complex (MHC) class I antigens are frequently found and may provide malignant cells with a mechanism to escape control of the immune system. This altered human lymphocyte antigen (HLA) class I phenotype can be caused by either structural alterations or dysregulation of genes encoding subunits of HLA class I antigens and/or components of the MHC class I antigen-processing machinery (APM). Herein we analyze the expression of several proteins involved in the generation of MHC class I epitopes in feline injection site sarcoma, a spontaneously occurring tumor in cats that is an informative model for the study of tumor biology in other species, including humans. Eighteen surgically removed primary fibrosarcoma lesions were analyzed, and an enhanced expression of two catalytic subunits of immunoproteasomes, PA28 and leucine aminopeptidase, was found in tumors compared to matched normal tissues. As a functional counterpart of these changes in protein levels, proteasomal activities were increased in tissue extracts from fibrosarcomas. Taken together, these results suggest that alterations in the APM system may account for reduced processing of selected tumor antigens and may potentially provide neoplastic fibroblasts with a mechanism for escape from T-cell recognition and destruction

    MHC class I-related antigen-processing machinery component defects in feline mammary carcinoma.

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    Defects in HLA class I antigen-processing machinery (APM) component expression and/or function are frequent in human tumors. These defects may provide tumor cells with a mechanism to escape from recognition and destruction by HLA class I antigen-restricted, tumor antigen-specific cytotoxic T cells. However, expression and functional properties of MHC class I antigens and APM components in malignant cells in other animal species have been investigated to a limited extent. However, this information can contribute to our understanding of the mechanisms underlying the association of MHC class I antigen and APM component defects with malignant transformation of cells and to identify animal models to validate targeted therapies to correct these defects. To overcome this limitation in the present study, we have investigated the expression of the catalytic subunits of proteasome (Y, X, and Z) and of immunoproteasome (LMP2, LMP7, and LMP10) as well as of MHC class I heavy chain (HC) in 25 primary feline mammary carcinomas (FMCs) and in 23 matched healthy mammary tissues. We found a reduced expression of MHC class I HC and of LMP2 and LMP7 in tumors compared with normal tissues. Concordantly, proteasomal cleavage specificities in extracts from FMCs were different from those in healthy tissues. In addition, correlation analysis showed that LMP2 and LMP7 were concordantly expressed in FMCs, and their expression was significantly correlated with that of MHC class I HC. The abnormalities we have found in the APM in FMCs may cause a defective processing of some tumor antigens

    Growing old with antiretroviral therapy or elderly people in antiretroviral therapy: two different profiles of comorbidity?

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    Background In persons living with HIV (PLWH), the burden of non-communicable chronic diseases increased over time, because of aging associated with chronic inflammation, systemic immune activation, and long-term exposure to the combination antiretroviral therapy (ART). Methods To explore the association of chronological age, age at first ART, and exposure to ART with non-communicable chronic diseases, we performed a cross-sectional analysis to evaluate the prevalence of comorbidities in patients enrolled in the SCOLTA Project, stratified by groups of chronological age (50-59 and 60-69 years) and by years of antiretroviral treatment (ART, <= 3 or > 3 years). Results In 1394 subjects (23.8% women), mean age at enrollment was 57.4 (SD 6.5) years, and at first ART 45.3 (SD 10.7). Men were older than women both at enrollment (57.6 vs 56.8, p = 0.06) and at first ART (45.8 vs 43.6, p = 0.0009). ART duration was longer in women (13.1 vs 11.7 years, p = 0.01). The age- and sex-adjusted rate ratios (aRRs, and 95% confidence interval, CI) showed that longer ART exposure was associated with dyslipidemia (aRR 1.35, 95% CI 1.20-1.52), hypertension (aRR 1.52, 95% CI 1.22-1.89), liver disease (aRR 1.78, 95% CI 1.32-2.41), osteopenia/osteoporosis (aRR 2.88, 95% CI 1.65-5.03) and multimorbidity (aRR 1.36, 95% CI 1.21-1.54). These findings were confirmed in strata of age, adjusting for sex. Conclusions Our data suggest that longer ART exposure was associated with increased risk of dyslipidemia, hypertension, and osteopenia/osteoporosis, hence the presence of multimorbidity, possibly due to the exposition to more toxic antiretrovirals. We observed different comorbidities, according to ART exposure and age
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