In vivo therapeutic efficacy of frog skin-derived peptides against Pseudomonas aeruginosa-induced pulmonary infection

Pseudomonas aeruginosa is an opportunistic and frequently drug-resistant pulmonary pathogen especially in cystic fibrosis sufferers. Recently, the frog skin-derived antimicrobial peptide (AMP) Esc(1-21) and its diastereomer Esc(1-21)-1c were found to possess potent in vitro antipseudomonal activity. Here, they were first shown to preserve the barrier integrity of airway epithelial cells better than the human AMP LL-37. Furthermore, Esc(1-21)-1c was more efficacious than Esc(1-21) and LL-37 in protecting host from pulmonary bacterial infection after a single intra-tracheal instillation at a very low dosage of 0.1 mg/kg. The protection was evidenced by 2-log reduction of lung bacterial burden and was accompanied by less leukocytes recruitment and attenuated inflammatory response. In addition, the diastereomer was more efficient in reducing the systemic dissemination of bacterial cells. Importantly, in contrast to what reported for other AMPs, the peptide was administered at 2 hours after bacterial challenge to better reflect the real life infectious conditions. To the best of our knowledge, this is also the first study investigating the effect of AMPs on airway-epithelia associated genes upon administration to infected lungs. Overall, our data highly support advanced preclinical studies for the development of Esc(1-21)-1c as an efficacious therapeutic alternative against pulmonary P. aeruginosa infection

Promising approaches to optimize the biological properties of the antimicrobial peptide esculentin-1a(1-21)NH2. amino acids substitution and conjugation to nanoparticles

Antimicrobial peptides (AMPs) represent an interesting class of molecules with expanding biological properties which make them a viable alternative for the development of future antibiotic drugs. However, for this purpose, some limitations must be overcome: (i) the poor biostability due to enzymatic degradation; (ii) the cytotoxicity at concentrations slightly higher than the therapeutic dosages; and (iii) the inefficient delivery to the target site at effective concentrations. Recently, a derivative of the frog skin AMP esculentin-1a, named esculentin-1a(1-21)NH2, [Esc(1-21): GIFSKLAGKKIKNLLISGLKG-NH2] has been found to have a potent activity against the Gram-negative bacterium Pseudomonas aeruginosa; a slightly weaker activity against Gram-positive bacteria and interesting immunomodulatory properties. With the aim to optimize the antimicrobial features of Esc(1-21) and to circumvent the limitations described above, two different approaches were followed: (i) substitutions by non-coded amino acids, i.e., α-aminoisobutyric acid or d-amino acids; and (ii) peptide conjugation to gold nanoparticles. In this mini-review, we summarized the structural and functional properties of the resulting Esc(1-21)-derived compounds. Overall, our data may assist researchers in the rational design and optimization of AMPs for the development of future drugs to fight the worldwide problem of antibiotic resistance

Analytic continuation of nucleon electromagnetic form factors in the time-like region

The possibility to compute nucleon electromagnetic form factors in the time-like region by analytic continuation of their space-like expressions has been explored in the framework of the Skyrme model. We have developed a procedure to solve analytically Fourier transforms of the nucleon electromagnetic current and hence to obtain form factors defined in all kinematical regions and fulfilling the first-principles requirements. The results are discussed and compared to data, both in space-like and time-like region.Comment: 34 pages, 15 figure

Progettazione di un dispositivo per il carico pelli in una linea produttiva di verniciatura

SOMMARIO Le caratteristiche delle pelli (deformabilità, delicatezza, dimensioni e bordi irregolari) sono le cause principali che hanno impedito uno sviluppo significativo nell’automazione dei sistemi di movimentazione nel settore conciario, soprattutto nelle fasi di carico sulle macchine di processo in cui è necessario che la pelle sia posizionata il più possibile stesa e priva di pieghe. La Sezione Produzione del Dipartimento di Ingegneria Meccanica, Nucleare e della Produzione dell’Università di Pisa svolge da anni studi in questo settore; in particolare è stato progettato e realizzato un prototipo di un dispositivo per il caricamento delle pelli sul trasportatore delle stazioni di verniciatura presenti all’interno delle concerie. Il presente lavoro di tesi ha l’obiettivo di progettare un dispositivo stenditore che segua la medesima sequenza operativa del prototipo, ma che tenga anche conto delle richieste funzionali provenienti dal settore conciario e delle problematiche individuate durante le prove eseguite sul dispositivo prototipale; la macchina dovrà essere realmente in grado di interfacciarsi con i processi produttivi tipici delle concerie. Si sono quindi acquisiti i dati necessari per la definizione delle specifiche del dispositivo stenditore, attraverso visite presso le concerie e attraverso uno studio critico delle funzionalità del prototipo; si è eseguita un’analisi comparativa delle possibili soluzioni costruttive ipotizzate per soddisfare le prestazioni richieste e le condizioni limitanti individuate nella fase progettuale precedente. Il risultato finale di questo lavoro di tesi è quello di aver progettato una macchina capace di: • Eseguire la corretta stesura e caricamento delle pelli sulle macchine di processo; • Garantire un adeguato grado di ripetibilità delle operazioni svolte; • Interfacciarsi con le stazioni di verniciatura attualmente utilizzate nel processo produttivo conciario. Analizzando i risultati ottenuti, si sono identificati i possibili aspetti progettuali che potranno essere oggetto di sviluppi futuri

La pubblicita' comparativa in Italia

Riassunto analitico: Questo lavoro si propone di sviluppare il tema della pubblicità comparativa, analizzato limitatamente al territorio italiano anche se vi sono brevi cenni alle realtà degli altri Paesi europei e degli Stati Uniti. Nonostante la natura della tesi sia prettamente giuridica e miri ad analizzare l’insieme delle norme relative a questo tipo di comunicazione, il primo capitolo è dedicato ad una visione di tipo aziendalistico. In questa parte si chiarisce infatti il ruolo di questa tipologia di pubblicità all’interno dell’impresa e si risponde alle domande su come, quando e perché deve essere utilizzata, e da chi. Il secondo capitolo ha invece il suo focus sull’inquadramento giuridico ante-direttiva del fenomeno comparativo. Qui si descrive l’art.2598 c.c., che indica come la fattispecie analizzata fosse inserita tra le maglie della concorrenza sleale, e si racconta il percorso evolutivo di interpretazione di tale articolo da parte della dottrina. Ampio spazio viene poi indirizzato all’istituto di natura privatistica, ma di grande rilevanza per il settore, costituito dall’autodisciplina pubblicitaria. La disciplina vigente, con i suoi sviluppi a partire dalla direttiva comunitaria 97/55 per arrivare sino ai giorni nostri, è invece trattata nel terzo capitolo. In tale ambito viene dedicata una parte anche alla descrizione delle aspettative e degli “umori” degli addetti ai lavori alle porte del d.lgs. 67/2000. Il quarto capitolo si concentra sui casi giurisprudenziali nell’arco di tempo che intercorre tra l’entrata in vigore del suddetto decreto e la fine del 2007. All’analisi della casistica seguono possibili spunti di interesse ed indicazioni. Il lavoro termina con le personali conclusioni dell’autore. Analytical summary: This paper wants to carry out a deepening on the comparative advertising. This topic is analysed making a restriction to the Italian reality, although the end of chapter two motions to foreign experiences. In spite of the thesis’ juridical nature, chapter one is dedicated to a business view of this kind of instrument. This part explains comparative advertising’s role inside a firm and it answers to the questions on how, when and why it must be used, and by who. Chapter two is focused on the subject’s juridical incorporation before the community directive. Here is a description of civil code’s art. 2598, which shows how the studied case was included in the unfair competition. Besides, there’s a comment on the evolution of the doctrine’s interpretation of this article, and there is also a large explanation of the important private institution of advertising autoregulation. Chapter three deals with the laws in force, starting from the community directive 97/55 and following with all later changes. Here is also a description of insiders’ expectation and “humour” at the eve of d.lgs. 67/2000. The fourth chapter is focused on jurisprudence’s cases from 2000 to 2007. After the cases’ analysis there are some author’s deductions and indications. The paper ends with the author’s conclusion

Transsulfuration pathway thiols and methylated arginines: the hunter community study

Background: Serum homocysteine, when studied singly, has been reported to be positively associated both with the endogenous nitric oxide synthase inhibitor asymmetric dimethylarginine [ADMA, via inhibition of dimethylarginine dimethylaminohydrolase (DDAH) activity] and with symmetric dimethylarginine (SDMA). We investigated combined associations between transsulfuration pathway thiols, including homocysteine, and serum ADMA and SDMA concentrations at population level. Methods: Data on clinical and demographic characteristics, medication exposure, C-reactive protein, serum ADMA and SDMA (LC-MS/MS), and thiols (homocysteine, cysteine, taurine, glutamylcysteine, total glutathione, and cysteinylglycine; capillary electrophoresis) were collected from a sample of the Hunter Community Study on human ageing [n = 498, median age (IQR) = 64 (60–70) years]. Results: Regression analysis showed that: a) age (P = 0.001), gender (P = 0.03), lower estimated glomerular filtration rate (eGFR, P = 0.08), body mass index (P = 0.008), treatment with beta-blockers (P = 0.03), homocysteine (P = 0.02), and glutamylcysteine (P = 0.003) were independently associated with higher ADMA concentrations; and b) age (P = 0.001), absence of diabetes (P = 0.001), lower body mass index (P = 0.01), lower eGFR (P&lt;0.001), cysteine (P = 0.007), and glutamylcysteine (P&lt;0.001) were independently associated with higher SDMA concentrations. No significant associations were observed between methylated arginines and either glutathione or taurine concentrations. Conclusions: After adjusting for clinical, demographic, biochemical, and pharmacological confounders the combined assessment of transsulfuration pathway thiols shows that glutamylcysteine has the strongest and positive independent associations with ADMA and SDMA. Whether this reflects a direct effect of glutamylcysteine on DDAH activity (for ADMA) and/or cationic amino acid transport requires further investigations.</br

Status and trend of ground-level ozone at the CONECOFOR plots, 1996 - 2005

Ozone measurements are performed since 1996 at the Permanent Monitoring Plots (PMPs) of the National Integrated Programme for Forest Ecosystem Monitoring (CONECOFOR). Weekly ozone concentrations are determined by passive samplers during spring and summer months, over a time period of 10 yrs. We analyzed data collected over a time period of ten years. Ozone shows potentially phytotoxic concentrations especially at the plots located in the central and Southern regions. Although monitoring periods at the different plots are not homogeneous, statistically significant differences between yearly concentrations of subsequent years were observed, highlighting a considerable temporal variability of ozone pollution levels. Trend analysis performed on ten years data series points out an increase of ozone concentrations over the considered time period at seven plots, all located in central and Southern Italy. The same analysis performed on data collected during the vegetative period (April - September) at the different PMPs from 2001 to 2005 shows significant positive trends at 5 plots, three of them located in the Alpine region, and 2 in Southern Italy

The frog skin-derived antimicrobial peptide esculentin-1a(1-21)nh2 promotes the migration of human hacat keratinocytes in an egf receptor-dependent manner: a novel promoter of human skin wound healing?

One of the many functions of skin is to protect the organism against a wide range of pathogens. Antimicrobial peptides (AMPs) produced by the skin epithelium provide an effective chemical shield against microbial pathogens. However, whereas antibacterial/antifungal activities of AMPs have been extensively characterized, much less is known regarding their wound healing-modulatory properties. By using an in vitro re-epithelialisation assay employing special cell-culture inserts, we detected that a derivative of the frog-skin AMP esculentin-1a, named esculentin-1a(1-21)NH2, significantly stimulates migration of immortalized human keratinocytes (HaCaT cells) over a wide range of peptide concentrations (0.025-4 μM), and this notably more efficiently than human cathelicidin (LL-37). This activity is preserved in primary human epidermal keratinocytes. By using appropriate inhibitors and an enzyme-linked immunosorbent assay we found that the peptide-induced cell migration involves activation of the epidermal growth factor receptor and STAT3 protein. These results suggest that esculentin-1a(1-21)NH2 now deserves to be tested in standard wound healing assays as a novel candidate promoter of skin re-epithelialisation. The established ability of esculentin-1a(1-21)NH2 to kill microbes without harming mammalian cells, namely its high anti-Pseudomonal activity, makes this AMP a particularly attractive candidate wound healing promoter, especially in the management of chronic, often Pseudomonas-infected, skin ulcers