Mutual Prodrugs of 5-Fluorouracil: From a Classic Chemotherapeutic Agent to Novel Potential Anticancer Drugs

The development of potent antitumor agents with a low toxicological profile against healthy cells is still one of the greatest challenges facing medicinal chemistry. In this context, the “mutual prodrug” approach has emerged as a potential tool to overcome undesirable physicochemical features and mitigate the side effects of approved drugs. Among broad-spectrum chemotherapeutics available for clinical use today, 5-fluorouracil (5-FU) is one of the most representative, also included in the World Health Organization model list of essential medicines. Unfortunately, severe side effects and drug resistance phenomena are still the primary limits and drawbacks in its clinical use. This review describes the progress made over the last ten years in developing 5-FU-based mutual prodrugs to improve the therapeutic profile and achieve targeted delivery to cancer tissues.     

Development of a dairy-based exopolysaccharide bioingredient

An exopolysaccharide (EPS)-producing Streptococcus thermophilus was used to develop an “all-dairy” ingredient with increased EPS content and greater functionality for dairy applications such as Mozzarella cheese. In laboratory-scale trials, milk protein hydrolysate (MPH), whey protein isolate (WPI) and whey protein hydrolysate (WPH) in reconstituted low-heat skim milk powder (LHSMP) were examined as additional dairy protein sources to increase the production of EPS. WPH supplementation resulted in the greatest EPS production. In batch fermentation, a medium based on LHSMP and WPH, combined with optimum conditions of temperature and pH, was used to obtain maximum production of EPS from S. thermophilus. EPS production was growth associated. The fermented biomass was harvested at the end of the exponential phase and freeze-dried. The reduced viable cell count and the retention of ropiness of the powder from the drying process enabled a higher level of EPS inoculation in a preliminary Mozzarella cheese manufacturing trial.     

Efficiency and equity considerations in financing agricultural research and extension

Benefits resulting from agricultural research and extension activities conducted in one region may affect producers and consumers throughout the country. Measurement of these benefit spillovers is required to equitably and efficiently finance these activities. Spillover benefit ratios per dollar of internal benefits for all farm production regions in the United States are calculated using an economic surplus framework to account for the effects of research and extension on both producers and consumers. In nine out of ten regions, the spillover ratios are greater than one, indicating that benefits accruing outside the region conducting research and extension activities are greater than the benefits accruing internally to the region. The average spillover ratio, which is 3.71 for all regions, is greater than the ratio of federal expenditures to regional expenditures. The implication of these ratios being unequal is that the federal contribution would need to be increased in order for regional costs to match regional benefits.     

Oxidation Processes in Sicilian Olive Oils Investigated by a Combination of Optical and EPR Spectroscopy

Abstract: Extra virgin olive oil (EVOO) is recognized as one of the healthiest foods for its high content of antioxidants, which forestall and slow down radical formation. Free radical‐initiated oxidation is considered one of the main causes of rancidity in fats and oils. As a consequence, reliable protocols for the investigation of oil oxidation based on selective, noninvasive, and fast methods are highly desirable. Here we report an experimental approach based on UV‐Vis absorbance, steady‐state fluorescence, and electron paramagnetic resonance (EPR) spectroscopy for studying oxidation processes induced by temperature for a period up to 35 d on Sicilian EVOO samples. We followed the decrease in β‐carotene content during incubation time and observed changes in polyphenols and tocopherols during the oxidation processes, focusing on the time scale of those changes. Using EPR spectroscopy, the free radical formation in different oil samples is reported, providing a fingerprint for both the antioxidant content and temporal features of the oxidation process at its early stage. Practical Application: We monitor β‐carotene and chlorophyll in an auto‐oxidation process. A protocol based on spectroscopic measurements is presented and can be used for the quality control process of commercial olive oil.     

Analysis of cubic and orthorhombic C<Subscript>3</Subscript>A hydration in presence of gypsum and lime

Field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) have been used to study the microstructural changes and phase development that take place during the hydration of cubic (pure) and orthorhombic (Na-doped) tricalcium aluminate (C₃A) and gypsum in the absence and presence of lime. The results demonstrate that important differences occur in the hydration of each C₃A polymorph and gypsum when no lime is added; orthorhombic C₃A reacts faster with gypsum than the cubic phase, forming longer ettringite needles; however, the presence of lime slows down the formation of ettringite in the orthorhombic sample. Additional rheometric tests showed the possible effects on the setting time in these cementitious mixes.     

Sustainable simultaneous communications in ad-hoc networks using smart antenna systems

This article proposes an analytical model for evaluating the number of simultaneous communications that can be sustained by an ad-hoc network in which the nodes are equipped with fully adaptive smart antennas. The presented mathematical framework adopts realistic models for the antenna radiation pattern and the channel behavior, and is able to take into account the network topology and the characteristics of the medium access control (MAC) protocol in the spatial domain. The model is employed to investigate the impact of the spatial channel model and of the angular spread on network performance. Additionally, this article examines the influence of the transmission policy of the control and data packets of the MAC layer on the number of simultaneous communications.     

Guest Editors' Editorial

Editorial Commentary

Guest Editors' Editorial     

Characterization of fire-refined copper recycled from scrap

Certain properties of fire-refined copper recycled from scrap have been characterized. A method is presented to calculate the half-softening temperature and the annealing temperature that allows 30% elongation to failure, hereinafter referred to as _30% temperature, on the basis of hardness measurements. The relation between ultimate strain and ultimate elongation has been studied and is described by a mathematicale xpression that seems to be independent of copper composition and annealing temperature. The microstructure of annealed samples reveals that recrystallization begins at half-softening temperature, and is ending at _30% temperature, although grain growth is not observed. An optimal range of oxygen content has been found that gives the minimum _30% temperature for each studied composition, and a mathematical expression with which to calculate those minimum temperatures is developed. The influence of cold-working degree on _30% temperature is also described; these temperatures reach a constant minimum value for each composition at high deformation degrees of cold-working.