UV-curable SiO2-TiO2 films for the realization of diffractive optical elements

Hybrid SiO2-TiO2 films are prepared starting from tetraisopropoxy titanate and 3-glycidoxipropyltrimethoxysilane, using the sol-gel process. During the sol synthesis titania clusters grow, conferring to the samples a photocatalytic activity. In this paper we exploit this property for the fabrication of surface-relief gratings. The realized structures are characterized by SEM, AFM and profilometric measurements, while the presence of titania clusters is confirmed by TEM analyses.     

Inherited Retinal Diseases Due to RPE65 Variants: From Genetic Diagnostic Management to Therapy

Inherited retinal diseases (IRDs) are a heterogeneous group of conditions that include retinitis pigmentosa (RP) and Leber congenital amaurosis (LCA) and early-onset severe retinal dystrophy (EO[S]RD), which differ in severity and age of onset. IRDs are caused by mutations in >250 genes. Variants in the RPE65 gene account for 0.6–6% of RP and 3–16% of LCA/EORD cases. Voretigene neparvovec is a gene therapy approved for the treatment of patients with an autosomal recessive retinal dystrophy due to confirmed biallelic RPE65 variants (RPE65-IRDs). Therefore, the accurate molecular diagnosis of RPE65-IRDs is crucial to identify ‘actionable’ genotypes—i.e., genotypes that may benefit from the treatment—and is an integral part of patient management. To date, hundreds of RPE65 variants have been identified, some of which are classified as pathogenic or likely pathogenic, while the significance of others is yet to be established. In this review, we provide an overview of the genetic diagnostic workup needed to select patients that could be eligible for voretigene neparvovec treatment. Careful clinical characterization of patients by multidisciplinary teams of experts, combined with the availability of next-generation sequencing approaches, can accelerate patients’ access to available therapeutic options.     

Flavonoids in three olive (Olea europaea) fruit varieties during maturation

The objective of the present paper was the characterisation of olive fruit varieties through the formation and variation during maturation of their flavonols, flavones and anthocyanins. An olive variety with a constant cyanidin-3-rutinoside:cyanidin-3-glucoside ratio of 1 exhibited lower contents of luteolin-7-glucoside and quercetin-3-rutinoside than varieties in which the only anthocyanin detected was cyanidin-3-rutinoside.     

Parameters for the evaluation of the thermal damage and nutraceutical potential of lupin-based ingredients and food products

Foods based on sweet lupin proteins are gaining attention from industry and consumers because of their possible role in the prevention of cardiovascular disease. When promoting lupin-based foods for inclusion in a daily diet, the thermal damage suffered during processing is of relevance to the bioactive and nutritional quality of the food product. N-(2-furoylmethyl)-L-lysine (furosine) quantification demonstrates that currently available sweet lupin protein isolates have a thermal damage comparable to or lower than other traditional food ingredients, and are a good source of lysine in non-dairy products. In lupin-based foods claiming to have cholesterol-lowering potential, shotgun proteomics offers itself as a fast and effective screening method for assessing the biological availability of active peptides. Such a method is readily applicable to other legume-enriched food products.     

Evaluation of potential side activities of commercial enzyme preparations used in winemaking

Twenty‐one commercial enzyme preparations used in winemaking were characterised for the α‐L‐rhamnosidase, α‐L‐arabinosidase, β‐D‐xylosidase, ?β‐D‐galactosidase, β‐D‐glucosidase, esterase, protease, cinnamoyl esterase and laccase activities. A new rapid fluorimetric method to assay esterase activity was developed. Enzyme preparations differed for the level of each enzyme activity assayed rather than for the type of enzymatic activity detected. High levels of protease, glycosidase, esterase and cinnamoyl esterase activity were found among enzyme preparations for different technological applications. A drastic reduction in the level of cinnamoyl esterase was observed in commercial grape juice, pH 3.6, total acidity 5.3 g L^?1_, sugar 170 g L^?1. Protease activity was only weakly reduced, from 10 to 20%, in commercial grape juice. β‐glucosidase activity levels are reduced in the presence of increasing concentration of glucose but are still present at the higher glucose concentration (100 g L^?1). The extent of the reduction observed was dependent on the enzymatic preparations tested.     

Nanoscale surface modifications of medically relevant metals: state-of-the art and perspectives

Evidence that nanoscale surface properties stimulate and guide various molecular and biological processes at the implant/tissue interface is fostering a new trend in designing implantable metals. Cutting-edge expertise and techniques drawn from widely separated fields, such as nanotechnology, materials engineering and biology, have been advantageously exploited to nanoengineer surfaces in ways that control and direct these processes in predictable manners. In this review, we present and discuss the state-of-the-art of nanotechnology-based approaches currently adopted to modify the surface of metals used for orthopedic and dental applications, and also briefly consider their use in the cardiovascular field. The effects of nanoengineered surfaces on various in vitro molecular and cellular events are firstly discussed. This review also provides an overview of in vivo and clinical studies with nanostructured metallic implants, and addresses the potential influence of nanotopography on biomechanical events at interfaces. Ultimately, the objective of this work is to give the readership a comprehensive picture of the current advances, future developments and challenges in the application of the infinitesimally small to biomedical surface science. We believe that an integrated understanding of the in vitro and particularly of the in vivo behavior is mandatory for the proper exploitation of nanostructured implantable metals and, indeed, of all biomaterials.     

Developing pyrrole-derived antimycobacterial agents: a rational lead optimization approach

Tuberculosis (TB) represents a never-ending challenge toward which research efforts are needed. Drug resistance is the key problem that scientists in the field need to fight. The development of new drugs endowed with novel modes of action against different biological targets is of extreme importance; these new agents should also exhibit lower toxicity compared with the anti-TB drugs currently available. Furthermore, new drugs should be inexpensive since most of the TB-infected population lives in developing nations. In the last few years, numerous researchers have focused their attention on TB, leading to the discovery of some interesting compounds. Among these, the pyrrole-derived compounds we developed can be considered very promising antimycobacterial agents. Aided by molecular modeling studies, we synthesized numerous compounds characterized by the same 1,5-diarylpyrrole scaffold and elucidated very interesting antitubercular/antimycobacterial properties. Some compounds identified are extremely promising and represent a step towards the design of novel lead structures in the fight against TB. Our efforts to this end are reviewed here.     

Color changes due to thermal ageing and artificial weathering of pigmented and textured ABS

Acrylonitrile–butadiene–styrene copolymers (ABS) are known to be sensitive towards ageing which can lead to color changes, primary interest in this study. The color changes were expressed in terms of the CIELAB color system. ABS plaques were subjected to heat ageing and artificial weathering. Uncolored ABS and dark gray colored specimens were employed. The pigmented ABS plaques were also imposed with different surface textures. In general, the uncolored material suffered from the most severe discoloration and the artificial weathering produced the strongest effect. For both types of specimens, a clear yellowing took place. Both the pigment system and the surface texture affected the color development during the ageing test. The latter can be of significant importance in certain applications when components with different surface textures are placed adjacent to each other. The surface micro‐hardness increased with increasing ageing time and its change followed that of the discoloration. Chemical changes of the surface layers were characterized by FTIR and were in accordance with results reported in the literature; i.e., an increase of the bands associated with carbonyl groups with increasing ageing time and a decrease of the bands associated with the polybutadiene phase clearly indicated chemical degradation due to ageing treatments. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers     

OPTIMAL KINETIC PARAMETERS AND BATCH MODELING FOR PECTIN HYDROLYSIS TO GALACTURONIC ACID WITH PECTINEX ULTRA SP-L ENZYME

Galacturonic acid is a monosaccharide obtained by pectin hydrolysis and a suitable substrate to produce bioethanol by fermentation. This article focuses on quantification of citrus pectin hydrolysis to galacturonic acid and provides new, reliable kinetic parameters for the Michaelis-Menten equation when the well-known commercial Pectinex Ultra SP-L is employed as enzyme. They are: r _max  = 1.10 g/(L min), K _m  = 10.42 g/L, and K _IGA  = 10.05 g/L, as obtained with a great accuracy by a nonlinear regression method and confirmed by the three classical linearization procedures (Lineweaver-Burk, Langmuir, and Eadie-Hofstee). The quantification of product inhibition has been achieved, with its inclusion in the rate equation. A batch reactor model yields perfect agreement between predictions and experiments, even under conditions different from those on which the parameters had been determined by regression.     

Synthesis and characterization of new poly(arylene ether 1,3,4-oxadiazole)s based on dihydroxynaphthalene isomers

Summary A series of new poly(arylene ether 1,3,4-oxadiazole)s has been obtained starting from a difluorosubstituted monomer containing 1,3,4-oxadiazole rings and some dihydroxynaphthalene isomers. The polymers have been prepared by polycondensation in solution and have been obtained in quantitative yield. They had inherent viscosity from 0.2 to 0.82 dL/g, showed good thermal stability (10% weight loss temperatures in nitrogen and air were above 460 and 450°C, respectively) and high glass transition temperatures (in the range of 197–232°C). The polymers were characterized by elemental and infrared analyses, GPC and wide angle X-ray diffraction. Received: 27 June 2000/Revised version: 2 October 2000/Accepted: 2 October 2000