Estudio de base de la Laguna de Ranchos para definir herramientas de aplicación municipal, para la gestión sostenible urbana ambiental y protección del recurso hídrico

La Laguna de Ranchos se en el partido de General Paz, sobre la RP 29, a 120 km de Buenos Aires y 85 Km de La Plata y viene sufriendo una modificación importante de su estado trófico natural por actividades humanas, afectando el uso recreativo y turístico de la misma. Ello motivó a la Municipalidad de Ranchos a solicitar a la Facultad de Ingeniería un estudio inicial específico, donde se propongan herramientas de gestión básicas para un manejo sustentable del recurso, a llevar adelante desde la Municipalidad. Se realizaron tareas de gabinete y de campo, incluyendo visitas periódicas, estudios climáticos, topobatimétricos, hidráulicos, hidroquímicos, bióticos, de calidad del agua y estado de las riberas, características de la cuenca y posibles fuentes de aporte de nutrientes y contaminantes. Se efectuaron recomendaciones para mejorar el estado de la laguna a fin de permitir usos que hoy no son viables, como el mantenimiento de un porcentaje de especies vegetales acuáticas, protección de las riberas, gestión de los residuos en el perilago, dragado en áreas específicas, plan de monitoreo de agua superficial (laguna y canales de entrada a la misma), instalación de una estación hidrometeorológica, y capacitación al personal municipal que realizará la posterior gestión

«... DISPERATAMENTE FECESI TURCHO»: Alipio di S. Giuseppe (1617-1645, OAD), tra adesione all'Islam, martirio e santità

Prigioniero a Tripoli e falso sacerdote. Apostata e penitente. Supposto martire e, pertanto, candidato alla santità. È questo il ritratto di Alipio di S. Giuseppe che emerge dalle fonti agiografiche e dal cospicuo, e in gran parte inedito, corpus documentario, di cui il primo capitolo della tesi offre un’articolata ricognizione. La vicenda di questo frate agostiniano scalzo di origine palermitana – che ben si inserisce nel contesto mediterraneo dei secoli XVI-XVII, caratterizzato da un continuo e ampio rimescolamento di uomini, merci, appartenenze religiose e culturali, e di cui la guerra di corsa, con tutte le sue conseguenze, costituisce una delle dimensioni più rappresentative – fu anzitutto una vicenda di prigionia, conversione all’islam e successiva abiura, nonché di martirio, cui il religioso andò volontariamente incontro nel febbraio del 1645; di questi aspetti, delle modalità con cui il tragico fatto fu trasmesso dai missionari apostolici residenti a Tripoli e recepito all’interno dell’Ordine degli Agostiniani Scalzi, oltre che delle interessanti analogie con altri episodi di apostasia si parla nel secondo capitolo. Nel terzo capitolo, invece, si dà conto del ruolo di primo piano avuto dalla famiglia siciliana dei Tomasi nella promozione della causa di beatificazione di fra Alipio, avviata in seguito all’arrivo, nel 1653, delle sue reliquie sul litorale agrigentino e approdata, dopo le ordinariae inquisitiones del biennio 1654-1656, alla Congregazione dei Riti, che però espresse parere negativo sia nel 1658 sia sessant’anni più tardi.Captive in Tripoli and false priest, apostate and penitent, alleged martyr and then candidate to sainthood. That is the portrait the first part of this work brought to light from the considerable documentary corpus about Alipio di San Giuseppe, mostly still unpublished. The human existence of this Augustinian Discalceate friar from Palermo – set in the XVI and XVII centuries, when in the Mediterranean mix of people, goods, religions, also privateering was a significant aspect – is a sequence of captivity, conversion to Islam and following abjuration, culminating in the martyrdom he deliberately chose in February 1645. This story, its narration made by the apostolic missionaries in Tripoli as wells as its understanding by the Augustinian Discalceate order are investigated in the second chapter and compared with similar episodes of abjuration. In the third part the relevant role played by the Sicilian family Tomasi in promoting the beatification proceedings of Alipio is explained; started after his relics were brought to the shore near Agrigento in 1653, the proceedings moved to the Congregatio Sacrorum Rituum after the ordinariae inquisitiones in 1654-1656, and there were denied first in 1658 and definitively 60 years later

Inorganic phosphate is a trigger factor for Microbispora sp. ATCC-PTA-5024 growth and NAI-107 production

BACKGROUND: NAI-107, produced by the actinomycete Microbispora sp. ATCC-PTA-5024, is a promising lantibiotic active against Gram-positive bacteria and currently in late preclinical-phase. Lantibiotics (lanthionine-containing antibiotics) are ribosomally synthesized and post-translationally modified peptides (RiPPs), encoded by structural genes as precursor peptides. The biosynthesis of biologically active compounds is developmentally controlled and it depends upon a variety of environmental stimuli and conditions. Inorganic phosphate (Pi) usually negatively regulates biologically-active molecule production in Actinomycetes, while it has been reported to have a positive control on lantibiotic production in Firmicutes strains. So far, no information is available concerning the Pi effect on lantibiotic biosynthesis in Actinomycetes. RESULTS: After having developed a suitable defined medium, Pi-limiting conditions were established and confirmed by quantitative analysis of polyphosphate accumulation and of expression of selected Pho regulon genes, involved in the Pi-limitation stress response. Then, the effect of Pi on Microbispora growth and NAI-107 biosynthesis was investigated in a defined medium containing increasing Pi amounts. Altogether, our analyses revealed that phosphate is necessary for growth and positively influences both growth and NAI-107 production up to a concentration of 5 mM. Higher Pi concentrations were not found to further stimulate Microbispora growth and NAI-107 production. CONCLUSION: These results, on one hand, enlarge the knowledge on Microbispora physiology, and, on the other one, could be helpful to develop a robust and economically feasible production process of NAI-107 as a drug for human use. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12934-014-0133-0) contains supplementary material, which is available to authorized users

Plateau Pressure during Pressure Control Ventilation

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A Two-Component regulatory system with opposite effects on glycopeptide antibiotic biosynthesis and resistance

The glycopeptide A40926, produced by the actinomycete Nonomuraea gerenzanensis, is the precursor of dalbavancin, a second-generation glycopeptide antibiotic approved for clinical use in the USA and Europe in 2014 and 2015, respectively. The final product of the biosynthetic pathway is an O-acetylated form of A40926 (acA40926). Glycopeptide biosynthesis in N. gerenzanensis is dependent upon the dbv gene cluster that encodes, in addition to the two essential positive regulators Dbv3 and Dbv4, the putative members of a two-component signal transduction system, specifically the response regulator Dbv6 and the sensor kinase Dbv22. The aim of this work was to assign a role to these two genes. Our results demonstrate that deletion of dbv22 leads to an increased antibiotic production with a concomitant reduction in glycopeptide resistance. Deletion of dbv6 results in a similar phenotype, although the effects are not as strong as in the Δdbv22 mutant. Consistently, quantitative RT-PCR analysis showed that Dbv6 and Dbv22 negatively regulate the regulatory genes (dbv3 and dbv4), as well as some dbv biosynthetic genes (dbv23 and dbv24), whereas Dbv6 and Dbv22 positively regulate transcription of the single, cluster-associated resistance gene. Finally, we demonstrate that exogenously added acA40926 and its precursor A40926 can modulate transcription of dbv genes but with an opposite extent: A40926 strongly stimulates transcription of the Dbv6/Dbv22 target genes while acA40926 has a neutral or negative effect on transcription of those genes. We propose a model in which glycopeptide biosynthesis in N. gerenzanensis is modulated through a positive feedback by the biosynthetic precursor A40926 and a negative feedback by the final product acA40926. In addition to previously reported control systems, this sophisticated control loop might help the producing strain cope with the toxicity of its own product. This work, besides leading to improved glycopeptide producing strains, enlarges our knowledge on the regulation of glycopeptide biosynthesis in actinomycetes, setting N. gerenzanensis and its two-component system Dbv6-Dbv22 apart from other glycopeptide producers

A Derivative of the Thiopeptide GE2270A Highly Selective against Propionibacterium acnes

A chemical derivative of the thiopeptide GE2270A, designated NAI003, was found to possess a substantially reduced antibacterial spectrum in comparison to the parent compound, being active against just a few Gram-positive bacteria. In particular, NAI003 retained low MICs against all tested isolates of Propionibacterium acnes and, to a lesser extent, against Enterococcus faecalis. Furthermore, NAI003 showed a time- and dose-dependent killing of both a clindamycin-resistant and a clindamycinsensitive P. acnes isolate. Gel shift experiments indicated that, like the parent compound, NAI003 retained the ability to bind to elongation factors Tu (EF-Tus) derived from Escherichia coli, E. faecalis, or P. acnes, albeit with reduced efficiency. In contrast, EF-Tus derived from the NAI003-insensitive Staphylococcus aureus or Streptococcus pyogenes did not bind this compound. These results were confirmed by in vitro studies using a hybrid translation system, which indicated that NAI003 can inhibit most efficiently protein synthesis driven by the P. acnes EF-Tu. P. acnes mutants resistant to NAI003 were isolated by direct plating. With one exception, all analyzed strains carried mutations in the tuf gene, encoding EF-Tu. Because of its selective effect on P. acnes in comparison to resident skin flora, NAI003 represents a promising candidate for the topical treatment of acne, which has already completed a phase 1 clinical study