Papers by Alexandra Gaspar
The aim of this study was to obtain new composites collagen-polyphenols and to investigate them a... more The aim of this study was to obtain new composites collagen-polyphenols and to investigate them as potential materials for wound dressings. Extracts from three plants: Arnica montana L., Artemisia absinthium L., and Urtica dioica L. were mixed in two different ratios and evaluated for their polyphenolic content and antioxidant activity. The herbal formulations were mixed with collagen type I and the obtained composite materials were chemically cross-linked with riboflavin. Their degree of cross-linking, enzymatic biodegradability, as well as their effect on fibroblasts growth and proliferation were comparatively assayed with non-crosslinked materials. The results demonstrated the potential of these porous composite materials for future application in wound care treatment.
Studia Universitatis Vasile Goldis: Seria Stiintele Vietii, 2016
The aim of this work was to develop a biotechnological approach for production of cauliflower as ... more The aim of this work was to develop a biotechnological approach for production of cauliflower as safe functional food, with an optimal content of chemopreventive compounds, by a protective biofortification, through selenium application together with betaine and spraying adjuvants. In the control and treated cauliflower plants we determined the amount of total selenium, glucosinolates (sulforaphane) and SAH (S-Adenosyl-homocysteine). We also assayed the chemopreventive effects of compounds formed in the treated cruciferous plants through in vitro tests, using human colorectal tumor cell line (CaCo2). Extracts of plants treated with selenium applied together with betaine and spraying adjuvant were significantly more active on reduction of tumoral cell viability than the extract of control plants. Cauliflower plants, obtained after our treatments for protective biofortification, were used to feed rabbits, for 10 days. The ingestion of biofortified cauliflower did not modify the hematol...
Periodontitis treatment using occlusive membranes presented variable efficacy due to their rapid ... more Periodontitis treatment using occlusive membranes presented variable efficacy due to their rapid degradation in the complex biologic environment of the damaged periodontium. The aim of this study was to prepare novel composites based on collagen, chondroitin sulfate and fibronectin, and to establish the optimal parameters for their photochemical cross-linking using riboflavin and UV exposure. The degree of cross-linking, biodegradability and density of all scaffold variants were investigated. Their cytotoxicity was evaluated in a culture of gingival fibroblasts by MTT assay and light microscopy. The results indicated that the higher the cross-linking degree, the lower was the scaffold biodegradation. Cell culture studies showed that composite scaffolds were favorable for cellular survival. In conclusion, the cross-linking method using riboflavin and UV exposure resulted in stable and biocompatible collagen-based composite scaffolds that could be used for periodontitis treatment.
Several plant products are used as antioxidant agents to treat inflammation-related disorders. In... more Several plant products are used as antioxidant agents to treat inflammation-related disorders. In recent years, encapsulation of biologic active compounds in lipid vesicles was shown to improve their bioavailability and transdermal delivery. The aim of this study was to prepare two arnica extracts of polyphenols (Pf) and polysaccharides (Pz) and their liposomal formulations (LPf, L-Pz) and to characterize their antioxidant and anti-inflammatory effect. Cytocompatible concentrations of Pf (50 μg/ml), Pz (0.5 μg/ml), L-Pf and L-Pz were tested for cytoprotective and anti-inflammatory activity in a model of hydrogen peroxide-stressed fibroblast cell culture by assessment of lactate dehydrogenase activity, cell morphology and pro-inflammatory cytokines production. The results demonstrated that L-Pf and L-Pz protected better the cell membrane against oxidative damage and had significantly (p<0.05) higher anti-inflammatory activity compared to their non-encapsulated forms. All these fin...
Cruciferous vegetables are known as food with chemopreventive effect due to their high content in... more Cruciferous vegetables are known as food with chemopreventive effect due to their high content in bioactive compounds, such as mineral nutrients, including selenium, antioxidants, vitamins and glucosinolates, which were shown to inhibit cancer cell growth, both in vitro and in vivo testing. The aim of this study was to evaluate the effect of a new selenium-based composition, applied on experimental field conditions to cauliflower plants (Brassica oleracea L.), on their chemopreventive compounds level and antitumoral activity. Treated plants, cultivated both in normal watered and water stress conditions, were compared for total selenium and sulforaphane contents, determined by electrothermal atomic absorption spectrometry (ETAAS) and high performance liquid chromatography (HPLC), respectively. In vitro cytotoxicity of cauliflower extracts was evaluated in NCTC fibroblast cell line, while their antitumoral activity was tested in Caco-2 human adenocarcinoma cell line using MTT colorime...
Agriculture and Agricultural Science Procedia, 2016
TURKISH JOURNAL OF BIOLOGY, 2016
Introduction Current standard therapy for full-thickness injuries, like chronic wounds or burns, ... more Introduction Current standard therapy for full-thickness injuries, like chronic wounds or burns, is transplantation with autologous skin grafts. In the last decade, epithelial sheets cultivated with keratinocytes and dermal fibroblasts were typically used for engraftment of patients with extensive skin injuries (Atiyeh and Costagliola, 2007). Although they appeared very promising, several limitations occurred over time, such as long culturing periods, low rates of cellular viability, risk of infection, and high cost (Lootens et al., 2013). Moreover, cell division arrest was reported after 30 to 40 population doublings, thus limiting the life span of keratinocytes in culture (Chapman et al., 2010). Stem cells represent a viable therapeutic alternative for skin repair due to their specific properties of self-renewal, high proliferation rate, and ability to develop terminally differentiated cells (Markeson et al., 2013). They can be easily isolated, in vitro multiplied, and used in autologous methodologies of regenerative medicine without the risk of tumor development (Silva et al., 2013). Many studies have reported isolation of mesenchymal stem cells (MSCs) from bone marrow (Bara et al., 2014), adipose tissue (Brzoska et al., 2005), or Wharton's jelly (Crisan, 2013), and their differentiation in cells of mesodermal origin like osteocytes, adipocytes, chondrocytes, and myocytes. Little research was focused on MSC differentiation into ectodermal lineage, like epidermal cells, in order to develop stem cell-based skin therapies (Zuk, 2013). To our knowledge, the mechanisms of adipose tissue-derived stem cells (ASCs) transdifferentiation into skin cell lineages and their therapeutic effects are currently discussed (Derby et al., 2014). The present study aimed to investigate the capacity of human ASCs to differentiate in vitro into a keratinocyte lineage, using specific induction medium containing a mixture of growth factors. The expression of distinctive keratinocyte markers was analyzed by immunofluorescence and RT-PCR. Additionally, the interaction between ASCs and HaCaT keratinocytes was investigated in two coculture assays using a viability test, light microscopy, and flow cytometry techniques.
Selenium (Se) has been proved to be an essential micronutrient for animals and microorganisms. Se... more Selenium (Se) has been proved to be an essential micronutrient for animals and microorganisms. Se is considered a beneficial element for plants, determining plant growth increase and enhanced response to biotic and abiotic stress. Se biofortification of food chain is considered essential for global health, but when applied on Brassicaceae family plants is interfering with sulfur (S) metabolism, reducing the accumulation of valuable S-phytonutrients. Moreover, Se-based biostimulants were acting first as potent pro-oxidants, bleaching the treated plants. Based on accumulated knowledge regarding cross-talking between Se and S assimilation pathways, we propose the development of a new biotechnological approach for protective biofortification of Brassica crops. The aim of this study was to develop new formulations of biostimulants, based on mixtures of betaine, selenium salt and spraying adjuvant, applied on cruciferous plants, in order to obtain safe functional food with enhanced chemop...
Agriculture and Food, 2017
We have obtained cabbage as functional food with high content of chemopreventive compounds by tre... more We have obtained cabbage as functional food with high content of chemopreventive compounds by treatment with a new plant biostimulant mixture containing selenium salt, betaine and spraying adjuvants. Such treatment determined an increased accumulation of selenium in cabbage plants, while maintaining a high content of glucosinolates. We have studied the in vitro antitumoral effect of selenium biofortified cabbage extracts using a tumor cell line and we observed a significant inhibition of cell proliferation, after 72 h of in cultivation. We did not observe modifications on the health status of laboratory rabbits fed with cabbage treated with the selenium-based biocomposition.
AgroLife Scientific Journal, 2015
Selenium (Se) has been proved to be an essential micronutrient for animals and microorganisms. Se... more Selenium (Se) has been proved to be an essential micronutrient for animals and microorganisms. Se is considered a beneficial element for plants, determining plant growth increase and enhanced response to biotic and abiotic stress. Se biofortification of food chain is considered essential for global health, but when applied on Brassicaceae family plants is interfering with sulfur (S) metabolism, reducing the accumulation of valuable S-phytonutrients. Moreover, Se-based biostimulants were acting first as potent pro-oxidants, bleaching the treated plants. Based on accumulated knowledge regarding cross-talking between Se and S assimilation pathways, we propose the development of a new biotechnological approach for protective biofortification of Brassica crops. The aim of this study was to develop new formulations of biostimulants, based on mixtures of betaine, selenium salt and spraying adjuvant, applied on cruciferous plants, in order to obtain safe functional food with enhanced chemop...
Microscopy and microanalysis : the official journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada, 2017
Cytological responses in different organs of sentinel organisms have proven to be useful tools fo... more Cytological responses in different organs of sentinel organisms have proven to be useful tools for characterizing the health status of those organisms and assessing the impact of environmental contaminants. Our study shows that nickel (II) accumulated in both germ cells (oogonia and developing oocytes) and somatic cells (muscle cells, follicle cells) in the Astacus leptodactylus ovary. Muscle cells from ovarian wall show disorganization and the disruption of cytoplasmic microtubules and pyknosis of the cell nucleus. Follicle cells, both those that surround the developing oocytes and also those that are not associated with the oocytes contained within the cytoplasm vacuoles of different sizes, degenerated mitochondria, myelin bodies, disorganized microtubules, and pyknotic nuclei. The most evident pathological phenomenon was the alteration and disorganization of the basal matrix, which separates the ovarian interstitium from ovarian follicles compartment. Exposure to nickel induces c...
Journal of medicine and life, Jan 15, 2011
The aim of this study was to obtain four collagen based porous scaffolds and to assess their in v... more The aim of this study was to obtain four collagen based porous scaffolds and to assess their in vitro biocompatibility and biodegradability in order to use them for skin tissue engineering. We have prepared four variants of collagen-based biodegradable sponges by liophilization of type I collagen solution and three variants of collagen-agarose mixture in different ratios 2:1 (A), 1:1 (B) and 1:2 (C). These scaffolds had microporous structure with a higher than 98% porosity and a reduced biodegradation after their exposure to UV radiation. The incorporation of agarose into the collagen scaffolds has improved their structural stability. In vitro biocompatibility testing for the four types of sponges was performed on a stabilized fibroblast cell line and showed that both cell viability and morphology were not altered by collagen and collagen-agarose variants A and B sponges. These three porous sponges demonstrated potential for future application as cell scaffolds in skin tissue engine...
Roumanian archives of microbiology and immunology
The aim of this study was to assess the antibacterial and antifungal potential of some Romanian m... more The aim of this study was to assess the antibacterial and antifungal potential of some Romanian medicinal plants, arnica--Arnica montana, wormwood--Artemisia absinthium and nettle--Urtica dioica. In order to perform this antimicrobial screening, we obtained the vegetal extracts and we tested them on a series of Gram-positive and Gram-negative bacteria, and also against two fungal strains. The vegetal extracts showed antimicrobial activity preferentially directed against the planktonic fungal and bacterial growth, while the effect against biofilm formation and development was demonstrated only against S. aureus and C. albicans. Our in vitro assays indicate that the studied plant extracts are a significant source of natural alternatives to antimicrobial therapy, thus avoiding antibiotic therapy, the use of which has become excessive in recent years.
MRS Proceedings, 2012
ABSTRACTThe purpose of this study was to investigate the in vivo biocompatibility of a new compos... more ABSTRACTThe purpose of this study was to investigate the in vivo biocompatibility of a new composite made from collagen and liposomes coated with plant derived polysaccharide using a rat subcutaneous implantation model. Histological observation has shown that after five days post-implantation, granulation tissue with vascular dilatation and inflammatory cell infiltration was formed adjacent to the implanted scaffold. After two weeks post-implantation, scaffold was highly infiltrated with cells and many of multinucleated giant cells were found to be aligned along the implant/tissue interface. At four weeks the scaffold was completely infiltrated with cells and a fibrous connective capsule isolate the implanted scaffold from the surrounding tissue. The inflammatory response to the implanted scaffold was assessed by immunohistochemical staining for interleukin 1β. IL-1β was demonstrated early in the post-implantation period (five days), but after two weeks, the intensity of IL-1β stain...
Chemistry Central Journal, 2012
Background Arnica montana L. and Artemisia absinthium L. (Asteraceae) are medicinal plants native... more Background Arnica montana L. and Artemisia absinthium L. (Asteraceae) are medicinal plants native to temperate regions of Europe, including Romania, traditionally used for treatment of skin wounds, bruises and contusions. In the present study, A. montana and A. absinthium ethanolic extracts were evaluated for their chemical composition, antioxidant activity and protective effect against H2O2-induced oxidative stress in a mouse fibroblast-like NCTC cell line. Results A. absinthium extract showed a higher antioxidant capacity than A. montana extract as Trolox equivalent antioxidant capacity, Oxygen radical absorbance capacity and 2,2-diphenyl-1-picrylhydrazyl free radical-scavenging activity, in correlation with its flavonoids and phenolic acids content. Both plant extracts had significant effects on the growth of NCTC cells in the range of 10–100 mg/L A. montana and 10–500 mg/L A. absinthium. They also protected fibroblast cells against hydrogen peroxide-induced oxidative damage, at ...
Journal of Nanomaterials, 2014
Smart drug delivery systems with controllable properties play an important role in targeted thera... more Smart drug delivery systems with controllable properties play an important role in targeted therapy and tissue regeneration. The aim of our study was the preparation and in vitro evaluation of a collagen (Col) matrix embedding a liposomal formulation of chondroitin sulfate (L-CS) for the treatment of inflammatory disorders. Structural studies using Oil Red O specific staining for lipids and scanning electron microscopy showed an alveolar network of nanosized Col fibrils decorated with deposits of L-CS at both periphery and inner of the matrix. The porosity and density of Col-L-CS matrix were similar to those of Col matrix, while its mean pore size and biodegradability had significantly higher and lower values (P < 0.05), respectively. In vitro cytotoxicity assays showed that the matrix system induced high cell viability and stimulated cell metabolism in L929 fibroblast cell culture. Light and electron micrographs of the cell-matrix construct showed that cells clustered into the p...
Journal of medicine and life
The aim of this study was to obtain four collagen based porous scaffolds and to assess their in v... more The aim of this study was to obtain four collagen based porous scaffolds and to assess their in vitro biocompatibility and biodegradability in order to use them for skin tissue engineering. We have prepared four variants of collagen-based biodegradable sponges by liophilization of type I collagen solution and three variants of collagen-agarose mixture in different ratios 2:1 (A), 1:1 (B) and 1:2 (C). These scaffolds had microporous structure with a higher than 98% porosity and a reduced biodegradation after their exposure to UV radiation. The incorporation of agarose into the collagen scaffolds has improved their structural stability. In vitro biocompatibility testing for the four types of sponges was performed on a stabilized fibroblast cell line and showed that both cell viability and morphology were not altered by collagen and collagen-agarose variants A and B sponges. These three porous sponges demonstrated potential for future application as cell scaffolds in skin tissue engineering.
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Papers by Alexandra Gaspar