University of Rijeka

About: University of Rijeka is a education organization based out in Rijeka, Croatia. It is known for research contribution in the topics: Population & Tourism. The organization has 3471 authors who have published 7993 publications receiving 110386 citations. The organization is also known as: Rijeka University & Sveučilište u Rijeci.

A comprehensive overview of hepatoprotective natural compounds: mechanism of action and clinical perspectives.

Abstract: Hepatoprotective effects of natural compounds have been frequently attributed to their antioxidant properties and the ability to mobilize endogenous antioxidant defense system. Because of involvement of oxidative stress in virtually all mechanisms of liver injury, it is a reasonable presumption that antioxidant properties of these compounds may play a key role in the mechanism of their hepatoprotective activity. Nevertheless, growing evidence suggests that other pharmacological activities of natural compounds distinct from antioxidant are responsible for their therapeutic effects. In this review, we discussed currently known molecular mechanisms of the hepatoprotective activity of 27 most intensively studied phytochemicals. These compounds have been shown to possess anti-inflammatory, antisteatotic, antiapoptotic, cell survival and antiviral activity through interference with multiple molecular targets and signaling pathways. Additionally, antifibrotic properties of phytochemicals have been closely associated with apoptosis of hepatic stellate cells and stimulation of extracellular matrix degradation. However, although these compounds exhibit a pronounced hepatoprotective effects in animal and cell culture models, the lack of clinical studies remains a bottleneck for their official acceptance by medical experts and physicians. Therefore, controlled clinical trials have an imperative in confirmation of the therapeutic activity of potentially hepatoprotective compounds. Understanding the principles of the hepatoprotective activity of phytochemicals could guide future drug development and help prevention of clinical trial failure. Also, the use of new delivery systems that enhances bioavailability of poorly water soluble compounds may improve the results already obtained. Most importantly, available data suggest that phytochemicals possess a various degree of modulation of specific signaling pathways, pointing out a need for usage of combinations of several hepatoprotective compounds in both experimental studies and clinical trials.

Modeling damage in concrete caused by corrosion of reinforcement: coupled 3D FE model

Abstract: Reinforced concrete structures, which are exposed to aggressive environmental conditions, such as structures close to the sea or highway bridges and garages exposed to de-icing salts, often exhibit damage due to corrosion. Damage is usually manifested in the form of cracking and spalling of concrete cover caused by expansion of corrosion products around reinforcement. The reparation of corroded structure is related with relatively high direct and indirect costs. Therefore, it is of great importance to have a model, which is able to realistically predict influence of corrosion on the safety and durability of reinforced concrete structures. In the present contribution a 3D chemo-hygro-thermo-mechanical model for concrete is presented. In the model the interaction between non-mechanical influences (distribution of temperature, humidity, oxygen, chloride and rust) and mechanical properties of concrete (damage), is accounted for. The mechanical part of the model is based on the microplane model. It has recently been shown that the model is able to realistically describe the processes before and after depassivation of reinforcement and that it correctly accounts for the interaction between mechanical (damage) and non-mechanical processes in concrete. In the present paper application of the model is illustrated on two numerical examples. The first demonstrates the influence of expansion of corrosion products on damage of the beam specimen in cases with and without accounting for the transport of rust through cracks. It is shown that the transport of corrosion products through cracks can significantly influence the corrosion induced damage. In the second example the numerically predicted crack patterns due to corrosion of reinforcement in a beam are compared with experimental results. The influence of the anode–cathode regions on the corrosion induced damage is investigated. The comparison between numerical results and experimental evidence shows that the model is able to realistically predict experimentally observed crack pattern and that the position of anode and cathode strongly influences the crack pattern and corrosion rate.