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Background and Aims The present study investigated the effectiveness of bovine blood ( BB)-based products, compared with that of the widely used iron ethylenediaminedi-(2-hydroxyphenylacetic) acid ( Fe- EDDHA) synthetic chelate, in iron nutrition of grapevine graft combinations and rootstocks grown under different controlled conditions. Methods and Results In experiments under nutrient solution utilising rhizoboxes and pots, the effect of iron application treatments was evaluated through biometric and chlorophyll index measurements, leaf nutrient concentration and root scanning electron microscopy. Conclusions The bovine blood compounds improved iron nutrition of the grapevine similar to or better than Fe- EDDHA and enhanced root growth. Significance of the Study The experimental evidence indicates that BB-based products represent a sustainable alternative to synthetic chelates as Fe fertilisers. [ABSTRACT FROM AUTHOR]

EAK16 (AEAEAKAKAEAEAKAK) and seven alternating polar/hydrophobic oligopeptides (derived from EAK16 by primary structure modifications) were tested for their resistance to free radical attack, in view of their possible use as biomimetic coatings of biomedical devices; in fact, oxidative radical stress, mainly due to hydroxyl radicals (•OH), is a common physiological condition occurring under acute or chronic inflammatory response. •OH radicals, mimicking an endogenous radical stress, were generated by gamma-radiolysis of water solutions. IR and Raman spectroscopies were used to investigate the damages induced by free radicals on the oligopeptides, in particular on their folding and inter-chain interactions. Some oligopeptides, i.e. EAK16 (pept1), pept3 (obtained by K → O substitution), pept5 (A → Abu substitution), pept7 (insertion at the N-terminus of the RGD sequence), and pept8 (RGD insertion and 'scrambling' of the sequence) were not severely affected by the treatment and retained their prevalent structure (i.e. α-helix for pept8 and β-sheet for the others). The other peptides, i.e. pept2 (obtained by E → D substitution), pept4 (E → D and K → O substitutions) and pept6 (A → Y substitution), showed significant conformational changes (i.e. increase in the α-helix content) upon irradiation. In pept2 and pept4, modifications in hydrophobic and ionic interactions were observed; the latter were mainly ascribed to the decarboxylation of acidic amino acids. In pept6, the main target of the •OH attack was Tyr, as deduced by the strong variations observed in Tyr bands both in IR and Raman spectra. This study may contribute to gain insight into the different biological performances of the EAK16-derived peptides and to identify the most adequate materials usable for bone regeneration. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, the effect of increasing amounts of lysozyme (Lyso) and bovine serum albumin (BSA) on the behaviour of lecithin (DMPC) and cephalin (DMPE) liposomes was investigated by means of Raman and DSC techniques. The results showed that both proteins affected, but in a different way, both lecithin and cephalin liposomes. In the samples with lower Lyso concentrations (up to 2 % w/w), a small decrease on the main transition temperature ( T) was observed, whereas T increased by further addition of Lyso (up to 15.0 % w/w). At the same time, an increase of about 20 % in the Δ H of the transition was observed. Pre-transition was also affected in a greater extent by protein presence. When BSA interacted with liposomes, a smaller increase in the T values was observed with a contemporary increase of about 8 % in the associated Δ H. The data suggested that the BSA-liposomes interaction involves only the external surface of the bilayer, excluding thus any penetration into the liposomal hydrophobic core. On the contrary, a partial penetration into the bilayer is suggested when Lyso is added to liposomes. Both considered proteins strengthened the overall bilayer structure of DMPC liposomes, suggesting a decrease in the membrane permeability. Moreover, Lyso secondary structure changed by interaction with liposomes, as demonstrated by the Raman spectra behaviour, in particular in the case of DMPE. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the effect of increasing amounts of DPSO on the behaviour of lecithins (DMPC, DPPC) and cephalin (DMPE) liposomes was investigated by means of Raman, FT-IR and DSC techniques. The results show that DPSO strongly affect, but in a different way, both lecithins and cephalin liposomes. In presence of low DPSO amounts, the main effect was a small decrease followed by an increase in the transition temperatures of all lipids; on the contrary, marked differences between the two classes were observed at higher sulfoxide content and the thermograms are strongly affected by memory effects. The partial dehydration of the lipid surface and the modification induced on the water structure might explain the effects observed in presence of low DPSO content, whereas, at higher DPSO concentrations, the main role is played by the direct interactions between the sulfoxide and the liposome surface. Spectroscopic data exhibit that the DPSO interact with math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.gif" overflow="scroll"> NH 3 + and in cephalin and only with groups in lecithins. The extension of the study to the concentrated DPSO containing systems presents a relevant biological significance; as a consequence of the affinity to biomembranes, the sulfoxide concentration near the lipid surface increases noticeably. [Copyright &y& Elsevier]

Abstract: Four alternating polar/non-polar peptides derived from the self-assembling peptide EAK-16 (Ac-AEAKAEAKAEAKAEAK-NH2) were examined in comparison with the EAK-16 parent form (peptide 1), both as-synthesised and after deposition on TiO2. The peptides were studied for their possible use as biomimetic materials due to their auto-assembling properties and to the presence, in two of them, of the RGD sequence, an active modulator of cell adhesion. IR and Raman spectroscopies were used to investigate the influence of the amino acid substitutions in the sequence on the self-assembly before and after deposition on TiO2. SERS spectroscopy was also used to elucidate the interaction with metal. As regards the as-synthesised peptides, basic amino acid substitution (K→O, peptide 2) or contemporaneous acid and basic substitution (E→D and K→O, peptide 3) did not induce significant conformational changes with respect to peptide 1: the prevailing structure was beta-sheet (about 70%). The insertion of the RGD sequence (peptide 4), induced a decrease in beta-sheet content (50%); the simultaneous scrambling of the sequence (peptide 5) made alfa-helix the prevailing structure. After deposition on TiO2 all peptides showed that the interaction with the surface was mediated by carboxylate groups; peptides maintained a prevalent beta-sheet structure with slightly higher percentages for peptides 1 and 4 which proved to form a more ordered layer. In conclusion, the substitution of polar aminoacid residues influences the ability of self-assembling more than the insertion of the RGD sequence, while the scrambling of the sequence did not appreciably alter the peptide ability of self-assembling on TiO2. [Copyright &y& Elsevier]

Abstract: A multidisciplinary study of the thermal denaturation of lysozyme in the presence of three sulfoxides with different length in hydrocarbon chain (DMSO, DESO, and DPSO) was carried out by means of DSC, Raman spectroscopy, and SDS–PAGE techniques. In particular, the T d and ΔH values obtained from the calorimetric measurements showed that lysozyme is partially unfolded by sulfoxides but most of the conformation holds native state. The sulfoxide denaturing ability increases in the order DPSO>DESO>DMSO. Moreover, only DMSO and DESO have a real effect in preventing the heat-induced inactivation of the protein and their maximum heat-protective ability is reached when the DMSO and DESO amount is ⩾25% w/w. The sulfoxide ability to act as effective protective agents against the heat-induced inactivation was confirmed by the protein analysis. The enzymatic activity, as well as the SDS–PAGE analysis, suggested that DESO, having a low hydrophobic character and a great ability to stabilise the three-dimensional water structure, is the most heat-protective sulfoxide. An accurate evaluation of the heat-induced conformational changes of the lysozyme structure before and after sulfoxide addition was obtained by the analysis of the Raman spectra. The addition of DMSO or DESO in low concentration resulted to sensitively decrease the heat-induced structural modifications of the protein. [Copyright &y& Elsevier]

Abstract: In this paper, a DSC and Raman study of hydrated multilamellar DMPC (1,2-dimyristoyl-sn-glycero-3-phosphocholine) and DMPE (1,2-dimyristoyl-sn-glycero-3-phosphoethanolamine) liposomes in presence of increasing amounts of DDT is reported. The observed changes denote that DDT molecules interact with both phospholipids and that the interaction mainly involves the external part of the bilayer since the deep penetration into the hydrophobic core is prevented by the setting up of polar interactions between the three aliphatic C–Cl bonds of the trichloro group of DDT and the –N+(CH3)3 of DMPC or the –NH3 + groups of DMPE molecules. This behaviour was particularly evidenced in presence of DMPE, as the insertion of DDT molecules into the central part of the bilayer seems to be completely excluded. Moreover, in DMPE liposomes the overall structure of the bilayer changes to a well defined and structured ‘phase II’ in presence of even small DDT amounts. [Copyright &y& Elsevier]

• Neofusicoccum parvum is representing an emerging problem for apple productions. • L1 and L8 strains are able to completely inhibit pathogen sporification in wood. • Both strains reduced by 70% pathogen mycelial growth through non volatile compounds. • L8 was able to increase cellulose content in wood preventing a fast fungal attack. Aureobasidium pullulans strains L1 and L8 were used as an alternative strategy against Neofusicoccum parvum , pathogen of apple wood and fruit. Both strains displayed a great ability to reduce pathogen conidia germination of almost 50% and totally stop its sporification in wood of 'Gala' and 'Fuji' apple cultivars. In addition, by in vitro tests the antagonistic activity displayed by non-volatile metabolites produced by both yeasts was highlighted by 70% of reduction of the pathogen mycelial growth. On apple fruit, the pathogen severity was reduced by 66% and 50% in 'Gala', and 70% and 60% in 'Fuji' by L1 and L8 respectively. In wood, no statistical differences were observed between L1, L8 and the control, except for 'Fuji' wood, where L8 strain displayed a wood lesion reduction of 23% with respect to the untreated control. Infrared analysis showed how the presence of both strains on woody tissues helped preserving cellulose content, preventing in this way the faster wood degradation by the pathogen. In addition, L1 and L8 simply colonized the wood surface, probably displaying an endophytic attitude, an essential requirement for controlling N. parvum in field. [ABSTRACT FROM AUTHOR]

• Bacterial strains can represent a sustainable solution to preserve kiwifruit from skin pitting. • On kiwifruit, P. synxantha (117-2b) was the most effective strain against C. luteo-olivacea. • Antifungal compounds in the form of peptides were mainly detected by FT-IR analysis. • By qPCR analysis, C. luteo-olivacea showed great persistence in kiwifruit despite the treatments. Skin pitting currently represents one of the major postharvest diseases of kiwifruit and one of the most difficult to manage in packinghouses due to its latent behavior and the difficulty in predicting its emergence. Our research demonstrates the potential to use different bacterial strains (Pseudomonas synxantha and Bacillus spp.) instead of synthetic compounds to preserve kiwifruit from the development of postharvest skin pitting symptoms, following the momentum towards sustainable strategies. The antagonists tested with in vitro assays showed different efficacy rates against C. luteo-olivacea (strain Cad21) mycelial growth by producing non-volatile metabolites. The biochemical composition of the most active bacterial non-volatile secondary metabolites was described through FT-IR (Fourier-Transform Infrared) spectroscopy. Pseudomonas synxantha strain 117-2b emerged as the most active strain in in vivo experiments, both as a curative and preventive treatment (63% and 84.7% of inhibition, respectively). In addition to its ability to reduce disease incidence, the biological antagonism exerted by P. synxantha strain 117-2b was further demonstrated by qPCR analysis as a reduction in the pathogen's abundance. In view of these results, alternative solutions in the field and during postharvest storage could be considered to control C. luteo-olivacea of kiwifruit. [ABSTRACT FROM AUTHOR]

A serious problem in the production of gas turbine blades is the detection of residual ceramic cores inside the cooling passages; in fact, the presence of even small ceramic pieces affects turbine performance and may cause difficulties in successive manufacturing. Therefore, it is important to have a non-destructive technique that must be capable of detecting tiny ceramic fragments in a fast and easy way. In this perspective, the suitability of infrared thermography was investigated within cooperation between the University of Naples and the Europea Microfusioni Aerospaziali S.p.A. (EMA). Several blades of three different types were inspected revealing that in many cases infrared thermography can discover small ceramic fragments which were missed by X-ray inspection. In addition, infrared thermography allows gaining of information about other types of anomalies (e.g., surface defects) during the same testing step (by eventually changing the test parameters) and then saving time and money. The obtained results look promising in view of introducing infrared thermography among industrial instrumentation as an alternative to, or integrated with, the most currently utilized non-destructive techniques. [ABSTRACT FROM AUTHOR]

BACKGROUND: Metal ions are implicated in protein aggregation processes of several neurodegenerative pathologies, where the protein deposition occurs, and in the biotechnology field like the food technology where many processes in food manufacturing are based on thermal treatments. OBJECTIVE: The influence of Cu2+ or Zn2+ ions on the thermal aggregation process of Bovine β-lactoglobulin (BLG) and Bovine Serum Albumin (BSA), two protein models, was studied with the aim of delineating the role of these ions in the protein aggregation kinetics and to clarify the related molecular mechanisms. METHODS: The protein structure changes were monitored by Raman spectroscopy, whereas the aggregate growth was followed by Dynamic Light Scattering measurements. RESULTS: Both metal ions are able to favour the BLG aggregation, whereas only Zn2+ ions have a promoter effect on the thermal aggregation of BSA. The reason of this different behaviour is that the BLG aggregation evolution is manly affected by the redistribution of charges, whereas that of BSA by the metal coordination binding which depends on metal. CONCLUSIONS: Raman spectroscopy, combined with dynamic light scattering experiments, was very useful in identifying the role played by Cu2+ and Zn2+ on the aggregation pathways of BLG and BSA. The results provide evidence for the role of histidine residues both in the redistribution of charges and in the two modes of metal binding that take place in BLG- and BSA-containing systems, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Powders obtained by milling ceramics shells, already used as investment material in casting processes, were sintered to investigate their possible re-use in the production of ceramic refractories. The sintering behaviour of these powders, consisting essentially of silica and mullite, were analysed both in a heating run by conventional contact dilatometry and in an isothermal process via optical dilatometry. The mechanical properties of sintered composites formed with a matrix of fine powders and an inert coarse phase of the same material are evaluated and discussed in view of possible use in the production of refractory tiles. [Copyright &y& Elsevier]

Abstract: In this study, five different types of conventional and cross-linked polyethylene (XLPE) (γ-sterilised PE GUR1020, EtO-sterilised PE GUR1020, γ-sterilised PE GUR1050, EtO-sterilised XLPE GUR1020, EtO-sterilised XLPE GUR1050) acetabular cups were tested on a hip joint simulator run for 5 million cycles in order to compare the relative long-term wear resistance in relation to material properties (PE grade, conventional or cross-linked) and sterilisation method (EtO treatment or γ-irradiation). Gravimetric measurements revealed significant differences between the wear behaviours of the five sets of acetabular cups. Weight loss was found to decrease along the series: γ-sterilised PE GUR1020>EtO-sterilised PE GUR1020>γ-sterilised PE GUR1050>EtO-sterilised XLPE GUR1050>EtO-sterilised XLPE GUR1020. The wear results were discussed in relation to the crystallinity degree of the cups which was determined by micro-Raman spectroscopy coupled to partial least-squares analysis. Within both conventional and cross-linked PE series, it appeared that higher crystallinity samples (i.e. γ-sterilised PE GUR1020 and EtO-sterilised XLPE GUR1050, respectively) were characterised by higher wear rates. The higher weight loss observed for PE GUR1020 was explained in relation to its lower molecular weight with respect to PE GUR1050. Raman analysis showed that wear testing did not significantly modify the crystallinity degree of any of the tested acetabular cups. The most worn cup, i.e. γ-sterilised PE GUR1020, appeared the most homogeneously polished upon wear testing, as confirmed by the lowest standard deviation associated to the crystallinity value recorded in the centre of the cup. The results of this investigation have clearly shown a dramatic wear reduction in favour of the cross-linked polyethylene. [Copyright &y& Elsevier]