1,721,091 research outputs found
NMN adenylyltransferase and poly (ADP-Ribose) polymerase in bovine tissues and characterization of NMN adenylyltransferase from bull testis
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La cultura come resistenza e impegno civile
No full textIl mio contributo mira ad analizzare, in breve, le varie prospettive emerse il 17 novembre 2022 nel convegno "La cultura come resistenza e impegno civile: padre David Maria Turoldo, padre Ernesto Balducci e Pier Paolo Pasolini".My brief contribution aims to offer a concise analysis of the various perspectives that emerged on November 17, 2022 in the congress «La cultura come resistenza e impegno civile: padre David Maria Turoldo, padre Ernesto Balducci e Pier Paolo Pasolini»
Dental pathology of the skeletal remains of Pontecagnano, Salerno Italy: VII-IV centuries B.C.
No full textDental pathology of the skeletal remains of Pontecagnano, Salerno-Italy: VII-IV centuries B.C
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High Temperature Tensile Tests of the Lightweight 2099 and 2055 Al-Cu-Li Alloy: A Comparison
No full textThe present study deals with the high temperature characterization of the unconventional, lightweight AA2099 and AA2055 Al-Cu-Li alloys (density = 2.63 g/cm3and 2.71 g/cm3respectively), which are widely employed for aerospace structural components thanks to their high specific strength at room temperature. The alloys have been characterized through tensile tests at 200°C and 250°C, after different overaging heat treatments, with the aim to simulate the variation of mechanical properties occurring in a component operating at high temperature. At 200°C, AA2099 alloy shows equivalent or superior performance compared with AA2055; therefore, it exhibits advantages in terms of specific strength due to its lower density; T1precipitates, dominating AA2099 after overaging, are considered to provide effective strengthening. The reverse occurs at 250°C operating temperature, at which considerable improvements are offered by the combination of both Ω and θ′ precipitates, which are present in AA2055 matrix in all overaged conditions
Arginine-lysine swaps selectively enhance antimicrobial activity over cytotoxic activity of LL-37 peptide
No full textLL-37 is the only cationic peptide belonging to the cathelicidin family expressed in humans. LL-37 has bactericidal activity and exerts immunomodulatory functions, thus forming, together with other peptides, the first line of defense against infections. The formation of LL-37 aggregates in the presence of neutral membranes promotes lack of specificity for microbial cells, which could explain why LL-37 becomes cytotoxic towards eukaryotic cells at high concentrations. Cationic amino-acids such arginine (Arg) and lysine (Lys) are known determinants for bacterial killing; however very little is known about how Lys-Arg exchange can influence LL-37 biological activities. Since antimicrobial peptides are promising candidates for the development of novel anti-infective agents, we have compared the bactericidal and cytotoxic effects of five LL-37 variants with wild-type peptide. The bactericidal activity was tested against Escherichia coli and Streptococcus agalactiae, while cytotoxicity was measured against A549, a human bronchoepithelial cell line. We found clear differences in bacterial killing kinetics towards both pathogens when central Arg residues were mutated in Lys, with Arg more efficient than Lys in bacterial membrane permeation. Of interest, the Arg at position 34 can compensate for the absence of the Arg at position 19 and 23 and the presence of Lys at the other positions resulted in a diminished toxicity for eukaryotic cells. Our study sheds new light on key amino-acid residues of LL-37 and should be considered when novel cationic amphipathic peptides derived from LL-37 are designed
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