Raluca Ripan Institute of Chemistry

Cluj-Napoca, Romania

Raluca Ripan Institute of Chemistry

Cluj-Napoca, Romania
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Dascalu M.L.,University of Medicine and Pharmacy, Cluj-Napoca | Sarosi C.,Raluca Ripan Institute of Chemistry | Moldovan M.,Raluca Ripan Institute of Chemistry | Badea M.E.,University of Medicine and Pharmacy, Cluj-Napoca
Defect and Diffusion Forum | Year: 2017

Photodynamic therapy (PDT) also known as Phototherapy or Photo chemotherapy involves the use of a photoactive dye (photosensitive) which is activated by exposure to light of a certain wavelength in the presence of oxygen. Dentists have to deal regularly with oral infections which untreated may cause systemic infections. Oral infections such as caries, periodontal infections and infections of the oral mucosa are available lighting so photodynamic therapy is particularly suitable for oral diseases [1,2]. Antimicrobial chemical treatment is nowadays widely used in the prophylaxis and treatment of inflammation-induced plaque with the risk of resistance development. The use of photodynamic therapy as a therapeutic approach can eliminate this risk, however. Studies in the literature show that both Gram-positive bacteria and Gram-negative bacteria are susceptible to the treatment. Among the advantages of using this method is counted rapid elimination of bacteria, minimal chances of developing bacterial resistance and safety in terms of host tissue and existing normal microflora in the oral cavity [3]. Antimicrobial photodynamic therapy (aPDT) by photochemical reaction uses light at a specific wavelength to activate a nontoxic photosensitizer (PS) in the presence of oxygen to produce cytotoxic products. There are different PSs used in dentistry including methylene blue (MB), toluidine blue O (TBO), indocyanine green (ICG) and curcumin [4]. © 2017 Trans Tech Publications, Switzerland.

Saplontai-Pop A.,University of Medicine and Pharmacy, Cluj-Napoca | Mot A.,Babes - Bolyai University | Moldovan M.,Raluca Ripan Institute of Chemistry | Oprean R.,University of Medicine and Pharmacy, Cluj-Napoca | And 5 more authors.
Open Life Sciences | Year: 2015

Background: The extracts of Allium cepa are known for their medical use: antioxidant, antiinflammatory, antimicrobial, fibrinolytic and antiplatelet properties. Our study aims to establish, using in vitro tests, the antiplatelet and antioxidant character, the link between them and the extract acidity, from seven varieties of A. cepa. Methodology: The qualitative and quantitative presence of polyphenols and anthocyanins in the extracts was determined using UV-Vis and HPLC. Quantitative determination of the thiosulfinates compounds was calculated using their reaction with 4-mercaptopyridine. Antioxidant character was determined using 3 methods (FC, DPPH and TEAC), and antiplatelet effect was measured by in vitro tests on platelet rich plasma obtained from human blood. Principal Findings/Results: The white variety of A. cepa has the most alkaline pH, the largest amount of thiosulfinate compounds and the most powerful antiplatelet effect, but a very small amount of flavonoids and an antioxidant effect almost nonexistent, in contrast with red variety of A. cepa which is the opposite. Conclusions/Significance: The white variety of A. cepa had very high anitiplatelet activity suggesting the potential use of A. cepa extract in treating cardiovascular diseases. © 2015 Aniela Saplonţai-Pop et al. licensee De Gruyter Open.

Horovitz O.,Babes - Bolyai University | Cioica N.,INMA | Jumate N.,Technical University of Cluj Napoca | Pojar-Fenesan M.,Raluca Ripan Institute of Chemistry | And 4 more authors.
Studia Universitatis Babes-Bolyai Chemia | Year: 2011

Maize and potato starch samples were investigated by three scanning electron microscopy techniques (secondary electron imaging, Everhart Thornley secondary electron detection, backscattered electron imaging) at different magnifications. The starch granules were visualized and their shapes, surface morphology and size were revealed. From the SEM images the size distribution of the granules was inferred and compared for the different samples. These investigations will contribute to the characterization of native starches as raw materials for the production of biodegradable plastics.

Saplontai-Pop A.,University of Medicine and Pharmacy, Cluj-Napoca | Moldovan M.,Raluca Ripan Institute Of Chemistry | Oprean R.,University of Medicine and Pharmacy, Cluj-Napoca | Orasan O.,University of Medicine and Pharmacy, Cluj-Napoca | And 2 more authors.
Studia Universitatis Babes-Bolyai Chemia | Year: 2014

The present study aims to establish a correlation between the estimated thiosulfinate compound content of Allium cepa L. (A. cepa) juices and their antiplatelet activity. The juices were obtained from three different varieties of A. cepa, cultivated in three different regions of Romania.The thiosulfinate compound content was estimated using a spectrophotometric method, based on the reaction with 4-mercapto-pyridine (a chromogenic thiol, with a maximum absorbance coefficient at 324 nm). The constant of the reaction kinetic curve was obtained by overlapping experimental data with an exponential function of first degree.The antiplatelet activity of the mentioned juices was measured by using in vitro tests with platelet rich plasma (PRP) obtained from blood collected from healthy human people, with arachidonic acid as platelet agonist.A statistically significant direct proportionality between the estimated thiosulfinate compound content and the antiplatelet activity of the tested A.cepa juices was established. © 2014, Universitatea Babes-Bolyai, Catedra de Filosofie Sistematica. All rights reserved.

Popescu V.,Technical University of Cluj Napoca | Molea A.,Technical University of Cluj Napoca | Dinescu A.,National Institute for Research and Development in Microtechnologies | Rusu-Trisca C.,National Institute for Research and Development in Microtechnologies | And 2 more authors.
Chalcogenide Letters | Year: 2015

Optical properties of PbS crystals obtained by Chemical bath deposition (CBD) and ultrasonic chemical bath deposition (US-CBD) on glass substrates have been studied. Ultrasounds determined an increase of reflectance, refraction index, real and imaginary parts of dielectric constant, a decrease of absorption coefficient and a red shift of the maxims of absorption coefficient, extinction coefficient and imaginary part of dielectric constant. The bad gaps of the obtained crystals are higher than the values corresponding to bulk PbS both for sample obtained in static and ultrasonic bath. Ultrasounds determined the decreasing of direct band gaps and the increasing of Urbach energy. The changes of optical properties of the sample obtained in sonochemical conditions can be correlated with the increase of the crystallite and grain size. © 2015, National Institute R and D of Materials Physics. All rights reserved.

Saplontai-Pop A.,University of Medicine and Pharmacy, Cluj-Napoca | Moldovan M.,Raluca Ripan Institute of Chemistry | Ionescu C.,University of Medicine and Pharmacy, Cluj-Napoca | Suciu-Petrescu M.,University of Medicine and Pharmacy, Cluj-Napoca | And 2 more authors.
Key Engineering Materials | Year: 2016

Particular importance is given to natural therapy since ancient times, the main advantages are immediate availability, high tolerability for the body and reduced incidence of adverse reactions, compared to synthetic pharmaceuticals drugs. Allium cepa L. extracts has gained a special attention in recent times, some of their compounds showing promising antioxidant activity, anti-diabetic, anti-inflammatory, anticancer, antimicrobial, antihyperlipidemic, fibrinolytic, antiplatelet effects, immunomodulators, anti-ischemic effect. This review is to compile the valuable pharmacological effect of thiosulfinates compounds from Allium cepa L. extracts. In the last 100 years have been published over 1,200 scientific papers that describes in detail the potential medical effects of the Allium extracts, thanks to the over 200 components identified, including vitamins, sulfur compounds, flavonoids, aminoacids, proteins, lipids and elements such as selenium and various antioxidants [1,2,3]. In the composition of Allium cepa L., water is found in a proportion of 80-95%, the remaining 5-20% being the dry matter. From this, 65% is in the form of non-structural carbohydrate. In some varieties, most of the dry matter is stored like a carbohydrate (sugars) as fructan, a polymer based on fructose. In others varieties, the dry substance has small amounts of fructan and large amounts of glucose, fructose and sucrose. In dry matter, are found other categories of important chemical compounds with beneficial effects on human health: flavonoids and organosulphur compounds [4]. It is known that the antiplatelet agents are among the most used drugs by the specialist cardiologist, there are numerous studies showing a similar effect exercised by some extracts obtained from different varieties of plants belonging to the family Alliaceae (A. cepa L., A. sativum L., A. ampeloprasum L.); those containing organosulphur compounds with platelet aggregation inhibition effect. © 2016 Trans Tech Publications.

Mesaros A.S.,UMF Iuliu Hatieganu | Furtos G.,Raluca Ripan Institute of Chemistry | Mesaros M.F.,UMF Iuliu Hatieganu | Badea M.E.,UMF Iuliu Hatieganu
Applied Mechanics and Materials | Year: 2014

Shear Bond Strength testing is one of the most common used tests for Orthodontics Adhesives. However, the standardizations of such procedures is quite difficult due to a large number of factors. While scientists are designing their studies in order to reduce errors, sometime they may find themselves in front of technical difficulties. A custom device was developed in order to allow a testing procedure that is closer to in vitro conditions. The device, mounted on a material testing machine permits sample inclination to a degree that reduces tensile component to the shear stress, therefore more accurate readings of the values are available and standardization of shear bond testing procedures is more probable. © (2014) Trans Tech Publications, Switzerland.

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