1,015 research outputs found
Catalase A is involved in the response to photooxidative stress in Pseudomonas aeruginosa
No full textBackground: Pseudomonas aeruginosa is the etiological agent of systemic and skin infections that are often difficult to treat. Photodynamic therapy (PDT) and, more recently, phototherapy (PT), are emerging among antimicrobial treatments to be combined with antibiotics. Visible light, either alone or combined with a photo sensitizer (PS), elicits photooxidative stress that induces microbial death. The response of bacteria to phototherapy seems to involve the antioxidant machinery. This study relies on the effects of detoxifying catalase A (KatA) in response to PDT and PT-induced photooxidative stress.Methods: The photo- and photodynamic inactivation experiments have been targeted at P. aeruginosa PAO1 and its isogenic derivative katA(-) mutant. The microorganisms were irradiated by a wide-spectrum halogen-tungsten lamp or light-emitting diodes (LEDs). Two photosensitizers, Tetrakis-(1-methyl-4-pyridyl)-21H, 23porphine, tetra-p-tosylate (TMPyP) porphyrin and Toluidine Blue O (TBO), were applied as part of the photodynamic approach.Results: P. aeruginosa katA(-) mutant was more sensitive than wild-type strain PAO1 to wide-spectrum light and blue LED (464 nm) treatments. The complementation of KatA, in katA(-) mutant, restored the light response of wild-type PAO1. Upon TBO treatment and irradiation by visible light (halogen lamp or LED), the sensitivity of katA(-) mutant was significant higher (p = 0.028 and p = 0.045, respectively) than that of the PAO1 strain.Conclusions: This study provides the first description of KatA in the response to photooxidative stress induced by photo- and photodynamic therapy
“Tan oscuro como muy oscuro”: ¿dónde se ubica Ena Lucía Portela? = "As dark as very dark”: Where does Ena Lucía Portela stand?
No full textThe aim of the article is to study “As dark as
very dark”, a short, less known text by Cuban author
Ena Lucía Portela (1972). After commenting on its
place in the context of the volume edited by Iván de
la Nuez: Cuba y el día después: doce ensayistas nacidos
con la revolución imaginan el futuro (2002), we argue
that the question concerning Cuba’s future serves as
a pretext for Portela to try to defi ne her place as a Cuban
writer and as intellectual. She distances from the
literary currents that determined the Cuban literary
fi eld, and destabilizes her own position. The protagonist’s
characterization as a nowhere girl, the intertextuality
and the emphasis on scepticism illustrate her
elusive position that doesn’t fi t in any category.Nos proponemos estudiar “Tan oscuro
como muy oscuro”, un texto breve, menos conocido,
de la escritora cubana Ena Lucía Portela (1972).
Tras ubicar el texto en el volumen editado por Iván
de la Nuez, Cuba y el día después: doce ensayistas
nacidos con la revolución imaginan el futuro (2002),
argüimos que la pregunta sobre el futuro de Cuba le
sirve a Portela como pretexto para intentar defi nir su
lugar como intelectual y escritora cubana. No sólo
se distancia de las corrientes que han imperado en
el campo literario cubano, sino que desestabiliza su
propia ubicación. La caracterización de la protagonista
como nowhere girl, la intertextualidad y la insistencia
en el escepticismo ilustran su posición siempre
escurridiza que no cabe en ninguna categoría
La fortuna visiva di Ludovico nel Settecento bolognese
No full textPrassi obbligata nel percorso formativo degli artisti, prima ancora di divenire un obiettivo dell’attività dell’Accademia Clementina, fondata nel 1710, lo studio della tradizione artistica bolognese prevede una riflessione specifica sulla produzione di Ludovico Carracci. Nel contributo la fortuna visiva del pittore nel Settecento bolognese è ripercorsa attraverso le testimonianze figurative e biografiche più significative: copie, citazioni, interpretazioni tratte dalle sue invenzioni, prodotte da maestri anche molto diversi, come Marcantonio Franceschini, Felice Torelli, Giuseppe Maria Crespi, documentano la centralità del suo ruolo, riconosciuto ancora nella seconda metà del secolo nella lettura dei Gandolfi, e mantenutosi vivo nel momento difficile delle soppressioni napoleoniche, come attesta la riproduzione della pala nella chiesa di San Pietro Martire, condotta da Filippo Pedrini, resasi necessaria per risarcire il danno della requisizione
“Tan oscuro como muy oscuro”: ¿dónde se ubica Ena Lucía Portela?
No full textThe aim of the article is to study “As dark as
very dark”, a short, less known text by Cuban author
Ena Lucía Portela (1972). After commenting on its
place in the context of the volume edited by Iván de
la Nuez: Cuba y el día después: doce ensayistas nacidos
con la revolución imaginan el futuro (2002), we argue
that the question concerning Cuba’s future serves as
a pretext for Portela to try to defi ne her place as a Cuban
writer and as intellectual. She distances from the
literary currents that determined the Cuban literary
fi eld, and destabilizes her own position. The protagonist’s
characterization as a nowhere girl, the intertextuality
and the emphasis on scepticism illustrate her
elusive position that doesn’t fi t in any categoryNos proponemos estudiar “Tan oscuro
como muy oscuro”, un texto breve, menos conocido,
de la escritora cubana Ena Lucía Portela (1972).
Tras ubicar el texto en el volumen editado por Iván
de la Nuez, Cuba y el día después: doce ensayistas
nacidos con la revolución imaginan el futuro (2002),
argüimos que la pregunta sobre el futuro de Cuba le
sirve a Portela como pretexto para intentar defi nir su
lugar como intelectual y escritora cubana. No sólo
se distancia de las corrientes que han imperado en
el campo literario cubano, sino que desestabiliza su
propia ubicación. La caracterización de la protagonista
como nowhere girl, la intertextualidad y la insistencia
en el escepticismo ilustran su posición siempre
escurridiza que no cabe en ninguna categorí
Synthesis and antiviral activity of quinolone and oxazine derivatives
No full textA new class of synthetic quinonic compounds acting as antiproliferative agents”,. A. Bolognese, T. Di Meo, M. Manfra, G. Correale, O. Mazzoni, E. Novellino, G. Brunetti, L. Sanna, D. Del piano, P. La Colla
Abstract of XVIth International Symposium on Medicinal Chemistry
BOLOGNA
18-22 SETTEMBRE 200
Effect of blue light at 410 and 455 nm on Pseudomonas aeruginosa biofilm
No full textPseudomonas aeruginosa is an opportunistic pathogen resistant to many antibiotics, able to form biofilm and causes serious nosocomial infections. Among anti-Pseudomonas light-based approaches, the recent antimicrobial Blue Light (aBL) treatment seems very promising. The aim of this study was to evaluate the efficiency of blue light in inhibiting and/or eradicating P. aeruginosa biofilm. Light at 410 nm has been identified as successful in inhibiting biofilm formation not only of the model strain PAO1, but also of CAUTI (catheter-associated urinary tract infection) isolates characterized by their ability to form biofilm. Results of this work on 410 nm light also demonstrated that: i) at the lowest tested radiant exposure (75 J cm−2) prevents matrix formation; ii) higher radiant exposures (225 and 450 J cm−2) light impairs the cellular components of biofilm, adherent and planktonic ones; iii) light eradicates with a good rate young and older biofilms in a light dose dependent manner; iv) it is also efficient in inactivating catalase A, a virulence factor playing an important role in pathogenic mechanisms. Light at 455 nm, even if at a lower extent than 410 nm, showed a certain anti-Pseudomonas activity. Furthermore, light at 410 nm caused detrimental effects on enzyme activity of β-galactosidase and catalase A, and changes on plasmid DNA conformation and ortho-nitrophenyl-β-D-galactopyranoside structure. This study supports the potential of blue light for anti-infective and disinfection applications
Lo “stato di salute” nei distretti dell’Azienda Usl di Bologna: una (ri)lettura territoriale
No full textQuesto capitolo dà conto di alcune delle principali caratteristiche della popolazione della città metropolitana bolognese, per contestualizzare il lavoro svolto dalla rete “Datti una Mossa!” all’interno di un territorio che, seppur genericamente “ricco” e caratterizzato da un’elevata qualità della vita, è attraversato da profonde disomogeneità, disuguaglianze che rendono determinate fasce della popolazione più fragili, esposte in misura maggiore a rischi di vario tipo (sanitari, ma non solo). Riprendendo i dati proposti dallo "Stato di Salute" della popolazione prodotto dall'Ausl di Bologna, si propone una loro lettura territoriale, che enfatizza le disomogeneità esistenti tra i sei distretti dell'Azienda Usl bolognese
Bacterial melanin production by heterologous expression of 4 hydroxyphenylpyruvate dioxygenase from Pseudomonas aeruginosa
No full textPyomelanin is a reddish-brown pigment produced by bacteria of different genera and plays a variety of physiological roles. Proposals have been regarding the use of pyomelanin in various environmental, industrial and, more recently, cosmetic applications. In Pseudomonas aeruginosa, the enzyme 4‐hydroxyphenylpiruvate dioxygenase (Hpd) converts 4-hydroxyphenylpiruvate into homogentisic acid, which represents the key intermediate for melanin biosynthesis. This work aimed to obtain Escherichia coli cells overexpressing hpd gene from the PAO1 strain to produce large amounts of pyomelanin for biotechnological purposes. The recombinant dioxygenase expression gave E. coli JM109 the ability to produce pyomelanin. A series of biotransformations led us to choose the best experimental conditions for pyomelanin production. Cells were grown at the mid-exponential phase in a mineral medium with added glucose 10 mM as carbon and energy sources and casamino acid 0.2% w/v as an amino acid source. The administration of tyrosine 1 mM after 30 min of exposure to arabinose 1% w/v made it possible to purify 213 mg/L of pyomelanin after 6 days of biotransformation. In addition to the interesting biotechnological outcomes, the resulting expression system supports the correlation between the hpd gene from P. aeruginosa PAO1 and pyomelanin synthesis
Filippo Hercolani dall’Impero a Bologna. Commissioni architettoniche della famiglia Hercolani nel XVIII secolo
No full textL'articolo analizza la figura di Filippo Hercolani (1663-1722), ambasciatore imperiale in Italia, nella sua qualità di committente di palazzi e ville nel territorio bolognese.The article analyzes the figure of Filippo Hercolani (1663-1722), imperial ambassador to Italy, and palaces and villas in the Bolognese area being commissioned by him
- …
