Search

We address a non-linear programming problem to find the optimal scheme of dose fractionation in cancer radiotherapy. Using the LQ model to represent the response to radiation of tumour and normal tissues, we formulate a constrained non-linear optimization problem in terms of the variables number and sizes of the dose fractions. Quadratic constraints are imposed to guarantee that the damages to the early and late responding normal tissues do not exceed assigned tolerable levels. Linear constraints are set to limit the size of the daily doses. The optimal solutions are found in two steps: i) analytical determination of the optimal sizes of the fractional doses for a fixed, but arbitrary number of fractions n ; ii) numerical simulation of a sequence of the previous optima for n increasing, and for specific tumour classes. We prove the existence of a finite upper bound for the optimal number of fractions. So, the optimum with respect to n is found by means of a finite number of comparisons amongst the optimal values of the objective function at the first step. In the numerical simulations, the radiosensitivity and repopulation parameters of the normal tissue are fixed, while we investigate the behaviour of the optimal solution for wide variations of the tumour parameters, relating our optima to real clinical protocols. We recognize that the optimality of hypo or equi-fractionated treatment schemes depends on the value of the tumour radiosensitivity ratio compared to the normal tissue radiosensitivity. Fast growing, radioresistant tumours may require particularly short optimal treatments. [ABSTRACT FROM AUTHOR]

The present study investigated the potential antioxidant applications of Humulus lupulus L. as raw extract and nanoformulated in liposomes. H. lupulus is commonly used as a food ingredient, but it is also a promising source of specialized metabolites with health-promoting effects. In the extract obtained by hydroalcoholic maceration, 24 compounds were characterized using liquid chromatography-mass spectrometry analyses. The extract exhibited an interesting antioxidant activity in in vitro spectrophotometric and cell assays. The extract was nanoformulated into liposomes to exploit and improve its beneficial proprieties. The in vitro assays revealed that, after incorporation into liposomes, the extract's antioxidant activity was preserved and even improved. Moreover, a lower dose of the extract was required to prevent reactive oxygen species overproduction when included in the nanoformulation. These results confirm the advantages of nanoformulating herbal extract to maximize its health-promoting effects for a potential pharmaceutical application., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Dittrichia graveolens L. Greuter belonging to the Asteraceae family, is an aromatic herbaceous plant native to the Mediterranean region. This plant species has been extensively studied for its biological activities, including antioxidant, antitumor, antimicrobial, antifungal, anti-inflammatory, anticholinesterase, and antityrosinase, and for its peculiar metabolic profile. In particular, bioactivities are related to terpenes and flavonoids metabolites, such as borneol ( 40 ), tomentosin ( 189 ), inuviscolide ( 204 ). However, D. graveolens is also well known for causing health problems both in animals and humans. Moreover, the species is currently undergoing a dramatic northward expansion of its native range related to climate change, now including North Europe, California, and Australia. This review represents an updated overview of the 52 literature papers published in Scopus and PubMed dealing with expansion, chemistry (262 different compounds), pharmacological effects, and toxicology of D.   graveolens up to October 2021. The review is intended to boost further studies to determine the molecular pathways involved in the observed activities, bioavailability, and clinical studies to explore new potential applications.

The present work deals with an Ordinary Differential Equation (ODE) model specifically designed to describe the COVID-19 evolution in Italy. The model is particularised on the basis of National data about the infection status of the Italian population to obtain numerical solutions that effectively reproduce the real data. Our epidemic model is a classical SEIR model that incorporates two compartments of infected subpopulations, representing diagnosed and undiagnosed individuals respectively, and an additional quarantine compartment. Possible control actions representing social, political, and medical interventions are also included. The numerical results of the proposed model identification by least square fitting are analysed and commented with special emphasis on the estimation of the number of asymptomatic infective individuals. Our fitting results are in good agreement with the epidemiological data. Short and long-term predictions on the evolution of the disease are also given.

Tomato ( Solanum lycopersicum L.) is a precious source of specialized metabolites with a great role in human health. Many varieties of tomatoes characterize the south of Italy's agronomic production and biodiversity, thanks to its warm temperatures and favorable weather. The preservation of biodiversity is a major goal of recent years, as each variety shows a peculiar phytochemical profile and provides a wide variety of metabolites with health-beneficial properties. Among the wide range of tomato varieties, literature focused on the most commercially-known types, including San Marzano and Datterino, while this study considered typical South Italy varieties for the first time, as well as Crovarese and Arsicolo. The aim of our work is to enrich the current knowledge about the tomato by evaluating the carotenoid content, the phytochemical profile by HPLC-DAD, and the biological activity of the different parts (peel, fruit, pulp, and seeds) of niche cultivars compared with commercial ones. Radical scavenging activity, assessed by the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) method, was higher in Crovarese peel extract, while Arsicolo possessed the highest lycopene content, underlying the importance of local ecotypes as a precious source of health promoting compounds. However, out of all of the varieties considered, peel extract was the most active one, opening new insights on their valorization in light of the circular economy., Competing Interests: The authors declare no conflict of interest.