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Otopeni, Romania

Dumitriu B.G.,Biotehnos Computer | Olariu L.,Biotehnos Computer | Ene M.D.,Biotehnos Computer | Zglimbea L.,Biotehnos Computer | And 2 more authors.
Archives of the Balkan Medical Union | Year: 2013

UV radiation impact on cutaneous tissue is very high, initiating and promoting dermatological diseases, even skin cancer. Our experiments highlight the cellular mechanisms initiated by UV radiation at normal human keratinocyte level in order to assess the photoprotective potential of vegetal extracts from fenugreek - Trigonella foenumgraecum (Dermo-Sks and Dermo-Ska), alfalfa - Medicago sativa (Dermo-L) and wheat - Triticum aestivum (Dermo-Egr). The screening was performed on normal human keratinocyte cell line (HaCaT) irradiated with different doses of UV-A/UV-B, considering the following important parameters for photoageing pathogenesis: apoptosis, activation of intracellular reactive oxygen species, secretion of pro-inflammatory cytokines (IL6, IL8, TNF-α), ILl-α as an indicator of irritability, VEGF secretion-promoter of angiogenesis. The fenugreek extract containing steroidic saponines has a protective effect against UV-A radiation, acting on the inflammatory cytokines and ILlα and preventing the apoptosis induction, and as well as against UV-B radiation, stopping the inflammation and angiogenesis. The fenugreek extract containing steroidic aglicones has only anti-inflammatory action when cells are exposing at UV-A radiation, and anti-angiogenic one at UV-B exposure. The alfalfa extract is an anti-apoptotic and antiinflammatory agent for UV-B radiation, but photo-irritant (increase ILlα) under UV-A exposure. The wheat extract shows UV-A protective effect due to additional cellular defense actions. Our results could be the basis for a new approach in pharmaceutical industry, in the development of natural ingredients for topical products, with photo-protective potential. Source

Dumitriu B.G.,Biotehnos Computer | Olariua L.,Biotehnos Computer | Ene M.D.,Biotehnos Computer | Rosoiub N.,Ovidius University | Rosoiub N.,Academy of Romanian Scientists
Romanian Biotechnological Letters | Year: 2013

Decreased cell function in aged and photo damaged skin appears to be due to abnormalities in the signaling pathways that regulate matrix production. In human dermal fibroblasts, TGF-β not only functions as primary stimulus for collagen synthesis, but also reduced collagen degradation by inhibiting MMP-1 expression. Our studies were designed in order to define the fibroblasts proliferative status and molecular basis for changes in collagen homeostasis, induced by three phytocompounds, derivatives from triterpenic acids. The screening techniques we used are beads - based flow cytometry assay for the quantization of soluble proteins (TGF- β), collagen synthesis and Matrixmetaloproteinases (MMP) expression, cell cycle dynamics and successive proliferative generations' determination after fluorescent staining with propidium iodide (PI) and carboxy fluorescein diacetat succin imidil ester (CFSE). All three compounds stimulate fibroblasts proliferation, but their action on TGF- β cytosolic release is different: the glicosidate form of the phytocompound decrease this cytokine secretion and activate the metalloproteinase action as a consequence, but the other compounds stimulate TGF- β, having significant impact on matrix proteins relief. The therapeutic targets of the three compounds are: wound healing (matrix remodeling action, controlling fibrosis), catalysts of structural proteins synthesis, important in chronological ageing. © 2013 University of Bucharest. Source

Ene M.D.,Biotehnos Computer | Jipa I.,Polytechnic University of Bucharest | Maria G.,Polytechnic University of Bucharest | Stoica-Guzun A.,Polytechnic University of Bucharest | Stroescu M.,Polytechnic University of Bucharest
Revista de Chimie | Year: 2011

Evaluation of the mass transfer resistance in aerated, well-mixed, laboratory-scale bioreactors, and of the overall gas-liquid mass transfer coefficient KLa is essential in any further kinetic and optimization analysis of a bioprocess. This is the case of enzymatic oxidation reactions or bioprocesses involving living cell cultures, thus allowing distinguishing between kinetic and transporting terms in the mass balance equations. A quick and simple experimental procedure, conducted in the absence of any reaction, and involving repeated water de-aeration (even if not complete) by sparging, using compressed N2 and re-aeration, leads to evaluate the KLa coefficient from the dissolved oxygen recorded kinetic curves. Comparatively to the classical approach, the procedure can be applied without changing the reaction conditions and liquid composition. The derived coefficient can be then correlated with the mixing and aeration conditions, allowing the possibility to choose the optimal aeration regime. As the volumetric mass transfer coefficient is dependent on the system characteristics and of a large number of factors, such a quick methodology is preferred to replace an approximate value taken from literature as it allows an easy implementation on any commercial benchscale bioreactor and it may be carried out before starting the bioreaction. Source

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