1,412 research outputs found

    Biofilm producing Salmonella typhi: Chronic colonization and development of gallbladder cancer

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    Salmonella enterica subspecies enterica serovar Typhi is the aetiological agent of typhoid or enteric fever. In a subset of individuals, S. Typhi colonizes the gallbladder causing an asymptomatic chronic infection. Nonetheless, these asymptomatic carriers provide a reservoir for further spreading of the disease. Epidemiological studies performed in regions where S. Typhi is endemic, revealed that the majority of chronically infected carriers also harbour gallstones, which in turn, have been indicated as a primary predisposing factor for the onset of gallbladder cancer (GC). It is now well recognised, that S. Typhi produces a typhoid toxin with a carcinogenic potential, that induces DNA damage and cell cycle alterations in intoxicated cells. In addition, biofilm production by S. Typhi may represent a key factor for the promotion of a persistent infection in the gallbladder, thus sustaining a chronic local inflammatory response and exposing the epithelium to repeated damage caused by carcinogenic toxins. This review aims to highlight the putative connection between the chronic colonization by highly pathogenic strains of S. Typhi capable of combining biofilm and toxin production and the onset of GC. Considering the high risk of GC associated with the asymptomatic carrier status, the rapid identification and profiling of biofilm production by S. Typhi strains would be key for effective therapeutic management and cancer prevention

    How human papillomavirus replication and immune evasion strategies take advantage of the host DNA damage repair machinery

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    The DNA damage response (DDR) is a complex signalling network activated when DNA is altered by intrinsic or extrinsic agents. DDR plays important roles in genome stability and cell cycle regulation, as well as in tumour transformation. Viruses have evolved successful life cycle strategies in order to ensure a chronic persistence in the host, virtually avoiding systemic sequelae and death. This process promotes the periodic shedding of large amounts of infectious particles to maintain a virus reservoir in individual hosts, while allowing virus spreading within the community. To achieve such a successful lifestyle, the human papilloma virus (HPV) needs to escape the host defence systems. The key to understanding how this is achieved is in the virus replication process that provides by itself an evasion mechanism by inhibiting and delaying the host immune response against the viral infection. Numerous studies have demonstrated that HPV exploits both the ataxia-telangiectasia mutated (ATM) and ataxia-telangiectasia and rad3-related (ATR) DDR pathways to replicate its genome and maintain a persistent infection by downregulating the innate and cell-mediated immunity. This review outlines how HPV interacts with the ATM-and ATR-dependent DDR machinery during the viral life cycle to create an environment favourable to viral replication, and how the interaction with the signal transducers and activators of transcription (STAT) protein family and the deregulation of the Janus kinase (JAK)-STAT pathways may impact the expression of interferon-inducible genes and the innate immune responses

    Lo sviluppo sostenibile nella documentazione delle agenzie per l'ambiente

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    The work shortly illustrates the concept of sustainable development: as it has been originated and like it is introduced in Italy. Some Italian web sites dedicated to sustainable development are considered, concentrating the attention on the resources offered in the net from the environmental agencies. Some web pages of APAT (Italian Agency for Environmental Protection and Technical Services) site and ARPA (Regional Agencies for environmental protection) sites are presented

    Lo sviluppo sostenibile nella documentazione delle agenzie per l'ambiente

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    The work shortly illustrates the concept of sustainable development: as it has been originated and like it is introduced in Italy. Some Italian web sites dedicated to sustainable development are considered, concentrating the attention on the resources offered in the net from the environmental agencies. Some web pages of APAT (Italian Agency for Environmental Protection and Technical Services) site and ARPA (Regional Agencies for environmental protection) sites are presented

    The impact of human papilloma viruses, matrix metallo-proteinases and HIV protease inhibitors on the onset and progression of uterine cervix epithelial tumors: A review of preclinical and clinical studies

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    Infection of uterine cervix epithelial cells by the Human Papilloma Viruses (HPV) is associated with the development of dysplastic/hyperplastic lesions, termed cervical intraepithelial neoplasia (CIN). CIN lesions may regress, persist or progress to invasive cervical carcinoma (CC), a leading cause of death worldwide. CIN is particularly frequent and aggressive in women infected by both HPV and the Human Immunodeficiency Virus (HIV), as compared to the general female population. In these individuals, however, therapeutic regimens employing HIV protease inhibitors (HIV-PI) have reduced CIN incidence and/or clinical progression, shedding light on the mechanism(s) of its development. This article reviews published work concerning: (i) the role of HPV proteins (including HPV-E5, E6 and E7) and of matrix-metalloproteinases (MMPs) in CIN evolution into invasive CC; and (ii) the effect of HIV-PI on events leading to CIN progression such as basement membrane and extracellular matrix invasion by HPV-positive CIN cells and the formation of new blood vessels. Results from the reviewed literature indicate that CIN clinical progression can be monitored by evaluating the expression of MMPs and HPV proteins and they suggest the use of HIV-PI or their derivatives for the block of CIN evolution into CC in both HIV-infected and uninfected women

    Campylobacter jejuni fatal sepsis in a patient with non-Hodgkin’s lymphoma: Case report and literature review of a difficult diagnosis

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    Campylobacter jejuni (C. jejuni) bacteremia is difficult to diagnose in individuals with hematological disorders undergoing chemotherapy. The cause can be attributed to the rarity of this infection, to the variable clinical presentation, and to the partial overlapping symptoms underlying the disease. Here, we report a case of a fatal sepsis caused by C. jejuni in a 76-year-old Caucasian man with non-Hodgkin's lymphoma. After chemotherapeutic treatment, the patient experienced fever associated with severe neutropenia and thrombocytopenia without hemodynamic instability, abdominal pain, and diarrhea. The slow growth of C. jejuni in the blood culture systems and the difficulty in identifying it with conventional biochemical phenotyping methods contributed to the delay of administering a targeted antimicrobial treatment, leading to a fatal outcome. Early recognition and timely intervention are critical for the successful management of C. jejuni infection. Symptoms may be difficult to recognize in immunocompromised patients undergoing chemotherapy. Thus, it is important to increase physician awareness regarding the clinical manifestations of C. jejuni to improve therapeutic efficacy. Moreover, the use of more aggressive empirical antimicrobial treatments with aminoglycosides and/or carbapenems should be considered in immunosuppressed patients, in comparison to those currently indicated in the guidelines for cancer-related infections supporting the use of cephalosporins as monotherapy

    La fortuna di Lisippo nel Mediterraneo. Tra ‘imprenditorialità’, ‘politicizzazione’ e ‘strategie di reimpiego’

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    Il volume prende in esame la fortuna delle opere di Lisippo in età ellenistica e romana con nuove sollecitazioni e proposte inedite in merito all’“imprenditorialità” dell’artista nel Mediterraneo e al reimpiego politicizzato delle sue opere. Dopo oltre vent’anni dalla mostra “Lisippo. L’arte e la fortuna”, realizzata nel 1995, la fortuna delle opere dell’artista richiedeva una nuova riflessione, qui articolata in tre parti. Al tema della fortuna di Lisippo dall’età ellenistica all’età romana appartiene la disamina di S. Ensoli sulla eredità delle iconografie lisippee a partire dall’età tolemaica, mentre a quello dei soggetti lisippei più diffusi nel Mediterraneo si riferiscono le analisi dell’autrice sulle figure di Alessandro Magno, Eracle ed Eros. Altri modelli lisippei trattati sono: l’Agia di Lisippo in relazione al Donario di Cirene; Polidamante e il Pugile delle Terme; Kairòs e la sua fortuna letteraria; il Carro del Sole a Lindos e la sua ripresa iconografica nel Mediterraneo; l’iconografia lisippea di Poseidon nella propaganda politica di età tardorepubblicana; Vecchio Sileno, a proposito di una statua dei Musei Capitolini. Le conclusioni di S. Ensoli, infine, inquadrano Lisippo come “imprenditore” della sua arte e precursore della “copistica”

    Interactions between endothelial cells and HIV-1.

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    Endothelial cells (EC) participate in inflammatory and immune reactions by producing and responding to soluble mediators. Human immunodeficiency virus (HIV)-1 profoundly alters the features of EC. In some anatomical districts, they are infected by the virus and may represent a relevant reservoir. During lymphomononuclear cell diapedesis, EC activate virus replication in crossing cells. Direct or indirect damage of EC is particularly relevant in central nervous system, where blood-brain barrier perturbation is pivotal in neuronal degeneration. The observed alterations of EC adhesive properties contribute in altered leukocyte traffic from blood to lymphoid organs and tissues and play a role in the onset of immune surveillance alteration. These alterations of EC functions are relevant for the general vasculopathy, which marks the acquired immunodeficiency syndrome, and in particular are instrumental in the pathogenesis of Kaposi's sarcoma. Here we discuss the biological and molecular activation of EC in HIV-1 infection that represents the basis to understand the pathogenesis of HIV-1 associated vascular diseases
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