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Publications (13)3.03 Total impact

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    ABSTRACT: Recently, it has been demonstrated the presence of Kaempferol in the petals of Crocus S. flowers that are normally discarded [1]. Kaempferol is an important antiox-idant of the flavonoid family. Numerous reports have shown that kaempferol and/or its glycosides induce cell death in a variety of cancer cells from different tissues, also it can slow skin aging by contrasting enzymes that degrade the extracellular matrix. This antioxidant has been extracted from Crocus S. petals with different alcohols. Isolation and purification was done by flash column chromatography. Fractions were analysed by Thin Layer Chromatography (TLC). Kaempferol was further character-ised by infrared (IR), mass spectroscopy (MS) and nuclear magnetic resonance (1H & 13C NMR) spectroscopy. To be sure of the antioxidant property of the extracted Kaempferol, a DPPH test was performed. In this experiment, it was used a new hydrogel consisting of three polymers-Polyvinyl pyrrolidone (PVP), Agar, Polyethylene glycol (PEG) – and Kaempferol, mixed, reticulated and then sterilized by gamma irradiation at 25 kGy. [2]. For the in vitro experimental protocol, it was used a primary culture of fibroblasts taken from the subcutaneous tissue of a newborn mice, seeding the cells on a little square (1cm 2 area) of the hydrogel with Kaempferol. As the ISO protocol prescribes, the experiments were repeated 3 times, stopping the culture at the 3rd, 7th and 14th day after the seeding. For all steps, 3 Petri dishes were used as controls without the bioma-terial. At fixed deadline, all Petri dishes were stained, using the Wright method for cell counting and morphological evaluations. The microscopic analysis revealed the complete biocompatibility of the hydrogel. The Petri dishes with this kind of new hydrogel showed a production of collagen fibres similar of the Petri dishes without the hydrogel. The presence of this bioactive compound in saffron petals, paves the way of new possibilities for the best use of the Crocus S. hole flower. References
    68th National Conference Italian society of Anatomy and embriology; 09/2014
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    ABSTRACT: Recently, attention has been paid to the identification of natural antioxidants from the petals of Crocus S. flowers that are normally considered waste[1]. The antioxi-dant activities are mainly attributed to carotenoid compounds, like crocin. Scientific evidences demonstrate that this kind of compounds are among the most important natural plant sources of antioxidant activity in the human diet, protecting the body against damages caused by reactive oxygen species (ROS). This antioxidant was extracted using methanol and ethanol. In this experiment, it was used a new hydrogel consisting of three polymers-Polyvinyl pyrrolidone (PVP), Agar and Polyethylene glycol (PEG) – and Crocin, mixed, reticulated and then sterilized by gamma irradiation at 25 kGy. For the in vitro experimental protocol, it was used a primary culture of fibroblasts taken from the subcutaneous tissue of a newborn mice, seeding the cells on a little square (1cm 2 area) of both kinds of hydrogel. As the ISO protocol prescribes, the experiments were repeated 3 times for each kind of hydrogel, stopping the culture at the 3rd, 7th and 14th day after the seeding. For all steps, 3 Petri dishes were used as controls without biomaterials. At fixed deadline, all Petri dishes were stained, using the Wright method for cell counting and morphological evaluations. The microscopic analysis revealed the complete biocompat-ibility of the hydrogel. The Petri dishes with this kind of new hydrogel has an overproduction of collagen from the fibroblasts. The presence of this natural important compound in saffron petals, now offers new possibilities for the best use of the hole flower. This study is still in progress. References
    67th National Conference Italian anatomy and histology society; 09/2013
  • E-Polymers 01/2005; DOI:10.1515/epoly.2005.5.1.110 · 0.33 Impact Factor
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    ABSTRACT: It was shown that the living cell inclusion inside bulk alginate hydrogel matrix is a good method to protect them from external environment. But a lot of unsolved problems derived from this technical procedure when the cells, suspended inside the hydrogel matrix, are subjected to mechanical stress during the crosslinking process of polymer solution. To avoid this unfavourable compression on the cell surface, a new spongy alginate hydrogel matrix was made. To test this new spongy capsule performance, fibroblasts were included in this new spongy matrix. With these experiments it was showed that the cell growth inside these new hydrogel sponges, compared with a cell growing inside a conventional hydrogel bulk matrix, was very different.
    Molecular, Cellular and Tissue Engineering, 2002. Proceedings of the IEEE-EMBS Special Topic Conference on; 02/2002
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    ABSTRACT: Mechanical properties of polyvinylpyrrolidone hydrogel dressings were investigated as a function of production factor combinations. The experimental results show that the peak-load depends strongly on the PVP concentration, the break-strain is inversely dependent on the radiation dose and the modulus of elasticity depends mainly on the PVP concentration.
    Nuclear Instruments and Methods in Physics Research Section B Beam Interactions with Materials and Atoms 11/1995; 105(1-4):100-102. DOI:10.1016/0168-583X(95)00519-6 · 1.19 Impact Factor
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    ABSTRACT: Formation of hydrogels by means of radiation technique is described and some differences connected with irradiation in solid state and solution are pointed out. Structures of primary macroeradicals of some hydrophillic polymers are given. Examples of applications of hydrogels as drug delivery systems, implants, injectable systems, stimuli-responsive systems, hybrid-type organs as well as general requirements for such systems are reviewed. Hydrogel wound dressings produced by radiation technology and marketed in the Central Europe are described.
    Radiation Physics and Chemistry 08/1995; 46(2-46):161-168. DOI:10.1016/0969-806X(95)00007-K · 1.19 Impact Factor
  • L A Pajewski, G C Pantaleoni, J Rosiak
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    ABSTRACT: Hydrogels are a new revolutionary method used to dress wounds without using gauzes and cotton wool. Our hydrogels were produced by irradiation and are perfectly sterile and biocompatible. The innovation of this topical treatment permits direct contact of hydrogels on wounds and results in complete repair of wounds and ulcers that do not heal easily. The fundamental advantage are: disappearance of local pain, very good protection of wounds, easy removal of necrotic tissue, total adhesion on wounds and simple removal without pain, faster tissue repair.
    La Clinica terapeutica 12/1994; 145(11):373-82. · 0.33 Impact Factor
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    ABSTRACT: The PERT is a SPR (Reticular Programation System) based on statistic-mathematic models. Since some years they are applied to productive processes to increase the efficiency and effectiveness. They all have a same base structure which is the net that is composed by the logical succession of the event and the activity which has the part of the project. Determining the minimum time (to), the maximum one (tp) and the more frequent time (tm) of each activity and applying the statistic method PERT, one gets the probable duration (te) of every activity and the critical path of the net is placed in evidence. This is formed by the chain of those activities whose duration determines the total duration of the project. The Authors have desired to verify the applicability of SPR even to the "medical industry" and, more precisely, to the diagnostic process for the verification of radiculoneuropathy. Such pathology affects a large part of the active population. The diagnostic process in this case comprises besides an accurate neurological and clinical examination of the patient, also the x-ray exam, the electromyography, the Computed Tomography (CT) and the Magnetic Resonance Imaging (MR) exam. These last two investigations gives an increase of diagnostic accuracy. With the collaboration of the physicians of the diagnostic Service, the Authors have measured in every step of the diagnostic procedure the waiting time of 48 patients with low back pain. Applying the PERT method, it has been possible to put in evidence in the net the critical activities. They are such that their duration time determines the probable duration of the whole diagnostic process. Such duration in this case it corresponds to 91 days with a standard deviation of 33 days. The delay of any critical activity causes a lealy of the whole route. This delay influences negatively on the patient's health. Besides it determines an economic damage to the system because a relation cost/time exists. The systems of reticular programmation have as objective not only the one of improving the programmation and the control of the processes, but also the attainment of an optimum cost/time ratio, varying in a way that the total cost of the realization of the process is minimum. They represent a useful criterion to direct Quality Assurance (Q.A) in the local political sanitary context, within the bounds of organization of technical - scientific quality. An accurate application of the Q.A. should modify besides the duration of the critical activities.
    Annali di igiene: medicina preventiva e di comunità 01/1989; 1(3-4):577-90.
  • G Marinelli, L A Pajewski, C Porto, G Cerone
    Annali di igiene: medicina preventiva e di comunità 8(2):209-12.
  • G. Corradini, L.A. Pajewski, R. Volpe