941 resultados para MATURE PERMANENT INCISORS


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To detect expression of bone morphogenetic protein 15 (BMP15) and growth differentiation factor 9 (GDF9) in oocytes, and their receptor type 2 receptor for BMPs (BMPR2) in cumulus cells in women with polycystic ovary syndrome (PCOS) undergoing in vitro fertilization (IVF), and determine if BMPR2, BMP15, and GDF9 expression correlate with hyperandrogenism in FF of PCOS patients. Prospective case-control study. Eighteen MII-oocytes and their respective cumulus cells were obtained from 18 patients with PCOS, and 48 MII-oocytes and cumulus cells (CCs) from 35 controls, both subjected to controlled ovarian hyperstimulation (COH), and follicular fluid (FF) was collected from small (10-14 mm) and large (> 18 mm) follicles. RNeasy Micro Kit (Qiagen(A (R))) was used for RNA extraction and gene expression was quantified in each oocyte individually and in microdissected cumulus cells from cumulus-oocyte complexes retrieved from preovulatory follicles using qRT-PCR. Chemiluminescence and RIA assays were used for hormone assays. BMP15 and GDF9 expression per oocyte was higher among women with PCOS than the control group. A positive correlation was found between BMPR2 transcripts and hyperandrogenism in FF of PCOS patients. Progesterone values in FF were lower in the PCOS group. We inferred that BMP15 and GDF9 transcript levels increase in mature PCOS oocytes after COH, and might inhibit the progesterone secretion by follicular cells in PCOS follicles, preventing premature luteinization in cumulus cells. BMPR2 expression in PCOS cumulus cells might be regulated by androgens.

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Aims To evaluate the ability of multifocal transient pattern electroretinography (mfPERG) to detect neural loss and assess the relationship between mfPERG and visual-field (VF) loss in eyes with chiasmal compression. Methods 23 eyes from 23 patients with temporal VF defects and band atrophy of the optic nerve and 21 controls underwent standard automated perimetry and mfPERG using a stimulus pattern of 19 rectangles, each consisting of 12 squares. The response was determined for the central rectangle, for the nasal and temporal hemifields (eight rectangles each) and for each quadrant (three rectangles) in both patients and controls. Comparisons were made using variance analysis. Correlations between VF and mfPERG measurements were verified by linear regression analysis. Results Mean +/- SD mfPERG amplitudes from the temporal hemifield (0.50 +/- 0.17 and 0.62 +/- 0.32) and temporal quadrants (superior 0.42 +/- 0.21 and 0.52 +/- 0.35, inferior 0.51 +/- 0.23 and 0.74 +/- 0.40) were significantly lower in eyes with band atrophy than in controls (0.78 +/- 0.24, 0.89 +/- 0.28, 0.73 +/- 60.26, 0.96 +/- 0.36, 0.79 +/- 0.26 and 0.91 +/- 0.31, respectively). No significant difference was observed in nasal hemifield measurements. Significant correlations (0.36-0.73) were found between VF relative sensitivity and mfPERG amplitude in different VF sectors. Conclusions mfPERG amplitude measurements clearly differentiate eyes with temporal VF defect from controls. The good correlation between mfPERG amplitudes and the severity of VF defect suggests that mfPERG may be used as an indicator of ganglion cell dysfunction.

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Objective: The aim of this study was to compare the production of the chemokines CCL3 and CXCL12 by cultured dental pulp fibroblasts from permanent (PDPF) and deciduous (DDPF) teeth under stimulation by Porphyromonas gingivalis LPS (PgLPS). Material and Methods: Primary culture of fibroblasts from permanent (n=3) and deciduous (n=2) teeth were established using an explant technique. After the fourth passage, fibroblasts were stimulated by increasing concentrations of PgLPS (0 – 10 µg/mL) at 1, 6 and 24 h. The cells were tested for viability through MTT assay, and production of the chemokines CCL3 and CXCL12 was determined through ELISA. Comparisons among samples were performed using One-way ANOVA for MTT assay and Two-way ANOVA for ELISA results. Results: Cell viability was not affected by the antigen after 24 h of stimulation. PgLPS induced the production of CCL3 by dental pulp fibroblasts at similar levels for both permanent and deciduous pulp fibroblasts. Production of CXCL12, however, was significantly higher for PDPF than DDPF at 1 and 6 h. PgLPS, in turn, downregulated the production of CXCL12 by PDPF but not by DDPF. Conclusion: These data suggest that dental pulp fibroblasts from permanent and deciduous teeth may present a differential behavior under PgLPS stimulation.

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Objective: To evaluate the prevalence, types, location, and characteristics of enamel defects in anterior permanent teeth of patients with complete unilateral and bilateral cleft lip and palate, as well as the relation with the cleft. Setting: Hospital for Rehabilitation of Craniofacial Anomalies, Bauru, São Paulo, Brazil. Participants: Eighty patients of both genders, 12 years and older, with unilateral or bilateral cleft lip and palate. Methods: A single examiner carried out clinical examination under artificial light with a dental probe and mirror after drying teeth according to the modified DDE index. Results: Seventy-four of 80 patients presented with at least one tooth affected by enamel defects: 165 of 325 evaluated teeth (50.8%) presented enamel defects, with hypoplasia being the most prevalent (50.7%), followed by diffuse opacity (23.1%) and demarcated opacity (18.4%). The most affected tooth was 21 (36.5%), followed by 11 (34%), located at the middle (40%) and incisal (33%) thirds. Most defects occur at the buccal surface (47.7%), followed by the distal (22.7%), the mesial (19%), and the palatal (10.6%) surfaces. A significant relationship was found between the cleft side and enamel defects. Conclusion: Upper anterior teeth of patients with complete cleft lip and palate present a high prevalence of enamel defects; the highest percentage on the cleft side suggests that the cleft does influence the occurrence of enamel defects in permanent teeth.

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The purpose of this study was to compare the effects of active and passive lacebacks on antero-posterior position of maxillary first molars and central incisors during leveling phase. Twenty-three subjects with Class I and Class II malocclusion were treated with first premolars extraction using preadjusted appliances (MBT 0.022-inch brackets). The leveling phase was performed with stainless steel archwires only. The sample was divided into 2 groups: 14 subjects received active lacebacks (Group 1) and 9 subjects received passive lacebacks (Group 2). Lacebacks were made from 0.008-inch ligature wire. Lateral cephalometric radiographs were taken pre- and post-leveling phase. Student's t-test was applied to determine the differences between pre- and post-leveling mean values and to determine the mean differences between groups. In Group I, the first molars showed a significant mesial movement, whereas no change was observed in Group 2. In both groups, maxillary central incisor crowns moved to lingual side. In conclusion, active laceback produced anchorage loss of maxillary first molars whereas passive laceback did not affect the position of these teeth. Active and passive lacebacks were effective in preventing central incisor proclination.

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The aim of this study was to evaluate the effect of 2% chlorhexidine digluconate (CHX) on immediate bond strength of etch-and-rinse adhesive to sound (SD) and caries-affected (CAD) primary dentin compared with permanent dentin. Flat dentin surfaces from 20 primary molars (Pri) and 20 permanent molars (Perm) were assigned to 8 experimental groups (n=5) according to tooth type (Pri or Perm), dentin condition (SD or CAD - pH-cycling for 14 days) and treatment (control - C or 60 s application of 2% CHX solution after acid etching - CHX). The bonding system (Adper Single Bond 2) was applied according to manufacturer's instructions followed by resin composite application (Filtek Z250). After 24 h water storage, specimens with cross-section area of 0.8 mm² were prepared for being tested under microtensile test (1 mm/min). Data were submitted to ANOVA and Tukey's post hoc test (α=0.05). Failure mode was evaluated using a stereomicroscope at ×400. Treatment with CHX did not result in higher bond strength values than no pre-treatment (C groups), independently of tooth type. Primary teeth and caries-affected dentin showed significantly lower (p<0.05) bond strength means compared with permanent teeth and sound dentin, respectively. Predominance of adhesive/mixed failure was observed for all groups. CHX did not influence the immediate bond strength to sound or caries-affected dentin of primary and permanent teeth.

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In the past a change in temperature of 5°C most often occurred over intervals of thousands of years. According to estimates by the IPCC, in the XXI century is expected an increase in average temperatures in Europe between 1.8 and 4.0°C in the best case caused by emissions of carbon dioxide and other GHG from human activities. As well as on the environment and economic context, global warming will have effects even on road safety. Several studies have already shown how increasing temperature may cause a worsening of some types of road surface damages, especially rutting, a permanent deformation of the road structures consisting in the formation of a longitudinal depression in the wheelpath, mostly due to the rheological behavior of bitumen. This deformation evolves during the hot season because of the heating capacity of the asphalt layers, in fact, the road surface temperature is up to 24°C higher than air. In this thesis, through the use of Wheeltrack test, it was studied the behavior of some types of asphalt concrete mixtures subjected to fatigue testing at different temperatures. The objectives of this study are: to determine the strain variation of different bituminous mixture subjected to fatigue testing at different temperature conditions; to investigate the effect of aggregates, bitumen and mixtures’ characteristics on rutting. Samples were made in the laboratory mostly using an already prepared mixtures, the others preparing the asphalt concrete from the grading curve and bitumen content. The same procedure was performed for each specimen: preparation, compaction using the roller compactor, cooling and heating before the test. The tests were carried out at 40 - 50 - 60°C in order to obtain the evolution of deformation with temperature variation, except some mixtures for which the tests were carried out only at 50°C. In the elaboration of the results were considered testing parameters, component properties and the characteristics of the mixture. Among the testing parameters, temperature was varied for each sample. The mixtures responded to this variation with a different behavior (linear logarithmic and exponential) not directly correlated with the asphalt characteristics; the others parameters as load, passage frequency and test condition were kept constant. According to the results obtained, the main contribution to deformation is due to the type of binder used, it was found that the modified bitumen have a better response than the same mixtures containing traditional bitumen; to the porosity which affects negatively the behavior of the samples and to the homogeneity ceteris paribus. The granulometric composition did not seem to have interfered with the results. Overall has emerged at working temperature, a decisive importance of bitumen composition, than the other characteristics of the mixture, that tends to disappear with heating in favor of increased dependence of rutting resistance from the granulometric composition of the sample considered. In particular it is essential, rather than the mechanical characteristics of the binder, its chemical properties given by the polymeric modification. To confirm some considered results, the maximum bulk density and the air voids content were determined. Tests have been conducted in the laboratories of the Civil Engineering Department at NTNU in Trondheim according to European Standards.

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The "sustainability" concept relates to the prolonging of human economic systems with as little detrimental impact on ecological systems as possible. Construction that exhibits good environmental stewardship and practices that conserve resources in a manner that allow growth and development to be sustained for the long-term without degrading the environment are indispensable in a developed society. Past, current and future advancements in asphalt as an environmentally sustainable paving material are especially important because the quantities of asphalt used annually in Europe as well as in the U.S. are large. The asphalt industry is still developing technological improvements that will reduce the environmental impact without affecting the final mechanical performance. Warm mix asphalt (WMA) is a type of asphalt mix requiring lower production temperatures compared to hot mix asphalt (HMA), while aiming to maintain the desired post construction properties of traditional HMA. Lowering the production temperature reduce the fuel usage and the production of emissions therefore and that improve conditions for workers and supports the sustainable development. Even the crumb-rubber modifier (CRM), with shredded automobile tires and used in the United States since the mid 1980s, has proven to be an environmentally friendly alternative to conventional asphalt pavement. Furthermore, the use of waste tires is not only relevant in an environmental aspect but also for the engineering properties of asphalt [Pennisi E., 1992]. This research project is aimed to demonstrate the dual value of these Asphalt Mixes in regards to the environmental and mechanical performance and to suggest a low environmental impact design procedure. In fact, the use of eco-friendly materials is the first phase towards an eco-compatible design but it cannot be the only step. The eco-compatible approach should be extended also to the design method and material characterization because only with these phases is it possible to exploit the maximum potential properties of the used materials. Appropriate asphalt concrete characterization is essential and vital for realistic performance prediction of asphalt concrete pavements. Volumetric (Mix design) and mechanical (Permanent deformation and Fatigue performance) properties are important factors to consider. Moreover, an advanced and efficient design method is necessary in order to correctly use the material. A design method such as a Mechanistic-Empirical approach, consisting of a structural model capable of predicting the state of stresses and strains within the pavement structure under the different traffic and environmental conditions, was the application of choice. In particular this study focus on the CalME and its Incremental-Recursive (I-R) procedure, based on damage models for fatigue and permanent shear strain related to the surface cracking and to the rutting respectively. It works in increments of time and, using the output from one increment, recursively, as input to the next increment, predicts the pavement conditions in terms of layer moduli, fatigue cracking, rutting and roughness. This software procedure was adopted in order to verify the mechanical properties of the study mixes and the reciprocal relationship between surface layer and pavement structure in terms of fatigue and permanent deformation with defined traffic and environmental conditions. The asphalt mixes studied were used in a pavement structure as surface layer of 60 mm thickness. The performance of the pavement was compared to the performance of the same pavement structure where different kinds of asphalt concrete were used as surface layer. In comparison to a conventional asphalt concrete, three eco-friendly materials, two warm mix asphalt and a rubberized asphalt concrete, were analyzed. The First Two Chapters summarize the necessary steps aimed to satisfy the sustainable pavement design procedure. In Chapter I the problem of asphalt pavement eco-compatible design was introduced. The low environmental impact materials such as the Warm Mix Asphalt and the Rubberized Asphalt Concrete were described in detail. In addition the value of a rational asphalt pavement design method was discussed. Chapter II underlines the importance of a deep laboratory characterization based on appropriate materials selection and performance evaluation. In Chapter III, CalME is introduced trough a specific explanation of the different equipped design approaches and specifically explaining the I-R procedure. In Chapter IV, the experimental program is presented with a explanation of test laboratory devices adopted. The Fatigue and Rutting performances of the study mixes are shown respectively in Chapter V and VI. Through these laboratory test data the CalME I-R models parameters for Master Curve, fatigue damage and permanent shear strain were evaluated. Lastly, in Chapter VII, the results of the asphalt pavement structures simulations with different surface layers were reported. For each pavement structure, the total surface cracking, the total rutting, the fatigue damage and the rutting depth in each bound layer were analyzed.

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In this thesis, the industrial application of control a Permanent Magnet Synchronous Motor in a sensorless configuration has been faced, and in particular the task of estimating the unknown “parameters” necessary for the application of standard motor control algorithms. In literature several techniques have been proposed to cope with this task, among them the technique based on model-based nonlinear observer has been followed. The hypothesis of neglecting the mechanical dynamics from the motor model has been applied due to practical and physical considerations, therefore only the electromagnetic dynamics has been used for the observers design. First observer proposed is based on stator currents and Stator Flux dynamics described in a generic rotating reference frame. Stator flux dynamics are known apart their initial conditions which are estimated, with speed that is also unknown, through the use of the Adaptive Theory. The second observer proposed is based on stator currents and Rotor Flux dynamics described in a self-aligning reference frame. Rotor flux dynamics are described in the stationary reference frame exploiting polar coordinates instead of classical Cartesian coordinates, by means the estimation of amplitude and speed of the rotor flux. The stability proof is derived in a Singular Perturbation Framework, which allows for the use the current estimation errors as a measure of rotor flux estimation errors. The stability properties has been derived using a specific theory for systems with time scale separation, which guarantees a semi-global practical stability. For the two observer ideal simulations and real simulations have been performed to prove the effectiveness of the observers proposed, real simulations on which the effects of the Inverter nonlinearities have been introduced, showing the already known problems of the model-based observers for low speed applications.

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A two-dimensional model to analyze the distribution of magnetic fields in the airgap of a PM electrical machines is studied. A numerical algorithm for non-linear magnetic analysis of multiphase surface-mounted PM machines with semi-closed slots is developed, based on the equivalent magnetic circuit method. By using a modular structure geometry, whose the basic element can be duplicated, it allows to design whatever typology of windings distribution. In comparison to a FEA, permits a reduction in computing time and to directly changing the values of the parameters in a user interface, without re-designing the model. Output torque and radial forces acting on the moving part of the machine can be calculated. In addition, an analytical model for radial forces calculation in multiphase bearingless Surface-Mounted Permanent Magnet Synchronous Motors (SPMSM) is presented. It allows to predict amplitude and direction of the force, depending on the values of torque current, of levitation current and of rotor position. It is based on the space vectors method, letting the analysis of the machine also during transients. The calculations are conducted by developing the analytical functions in Fourier series, taking all the possible interactions between stator and rotor mmf harmonic components into account and allowing to analyze the effects of electrical and geometrical quantities of the machine, being parametrized. The model is implemented in the design of a control system for bearingless machines, as an accurate electromagnetic model integrated in a three-dimensional mechanical model, where one end of the motor shaft is constrained to simulate the presence of a mechanical bearing, while the other is free, only supported by the radial forces developed in the interactions between magnetic fields, to realize a bearingless system with three degrees of freedom. The complete model represents the design of the experimental system to be realized in the laboratory.

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More efficient water treatment technologies would decrease the water bodies’ pollution and the actual intake of water resource. The aim of this thesis is an in-depth analysis of the magnetic separation of pollutants from water by means of a continuous-flow magnetic filter subjected to a field gradient produced by permanent magnets. This technique has the potential to improve times and efficiencies of both urban wastewater treatment plants and drinking water treatment plants. It might also substitute industrial wastewater treatments. This technique combines a physico-chemical phase of adsorption and a magnetic phase of filtration, having the potential to bond magnetite with any conventional adsorbent powder. The removal of both Magnetic Activated Carbons (MACs) and zeolite-magnetite mix with the addition of a coagulant was investigated. Adsorption tests of different pollutants (surfactants, endocrine disruptors, Fe(III), Mn(II), Ca(II)) on these adsorbents were also performed achieving good results. The numerical results concerning the adsorbent removals well reproduced the experimental ones obtained from two different experimental setups. In real situations the treatable flow rates are up to 90 m3/h (2000 m3/d).

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OBIETTIVO : Quantificare le CECs/ml nei pazienti affetti da ischemia critica (IC) degli arti inferiori, eventuali correlazioni tra i fattori di rischio, lo stadio clinico con l’ aumento delle CECs. Valutare i cambiamenti strutturali (calcificazione ed infiltratto infiammatorio) e l’ angiogenesi (numero di capillari /sezione) della parete arteriosa. MATERIALI E METODI: Da Maggio 2006 ad Aprile 2008 in modo prospettico abbiamo arruolato paziente affetti da IC da sottoporre ad intervento chirurgico. In un data base abbiamo raccolto : caratteristiche demografiche, fattori di rischio, stadiazione dell'IC secondo Leriche-Fontaine (L-F), il tipo di intervento chirurgico. Per ogni paziente abbiamo effettuato un prelievo ematico di 2 ml per la quantificazione immunomagnetica delle CECs e prelievo di parete arteriosa. RISULTATI: In modo consecutivo abbiamo arruolato 33 pazienti (75.8% maschi) con età media di 71 aa (range 34-91aa), affetti da arteriopatia ostruttiva cronica periferica al IV stadio di L-F nel 84.8%, da cardiopatia ischemica cronica nel 60.6%, da ipertensione arteriosa nel 72.7% e da diabete mellito di II tipo nel 66.6%. Il valore medio di CECs/ml è risultato significativamente più elevato (p= 0.001) nei soggetti affetti da IC (CECs/ml =531.24 range 107- 3330) rispetto ai casi controllo (CECs/ml = 125.8 range 19-346 ). Le CECs/ml nei pazienti diabetici sono maggiori rispetto alle CECs/ml nei pazienti non diabetici ( 726.7 /ml vs 325.5/ml ), p< 0.05 I pazienti diabetici hanno presentato maggior incidenza di lesioni arteriose complesse rispetto ai non diabetici (66% vs 47%) e minor densità capillare (65% vs 87%). Conclusioni : Le CECs sono un marker sierologico attendibile di danno vascolare parietale, la loro quantità è maggiore nei pazienti diabetici e ipertesi. La minor capacità angiogenetica della parete arteriosa in presenza di maggior calcificazioni ed infiltrato infiammatorio nei diabetici, dimostra un danno istopatologico di parete maggiore .

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Intraflagellar transport (IFT) is required for the assembly and maintenance of cilia. In this study we analyzed the subcellular localization of IFT proteins in retinal cells by correlative high-resolution immunofluorescence and immunoelectron microscopy. The rod photoreceptor cell was used as a model system to analyze protein distribution in cilia. To date the expression of IFT proteins has been described in the ciliary region without deciphering the precise spatial and temporal subcellular localization of IFT proteins, which was the focus of my work. rnThe establishment of the pre-embedding immunoelectron method was an important first step for the present doctoral thesis. Results of this work reveal the differential localization of IFT20, IFT52, IFT57, IFT88, IFT140 in sub-ciliary compartments and also their presence in non-ciliary compartments of retinal photoreceptor cells. Furthermore, the localization of IFT20, IFT52 and IFT57 in dendritic processes of non-ciliated neurons indicates that IFT protein complexes also operate in non-ciliated cells and may participate in intracellular vesicle trafficking in eukaryotic cells in general.rnIn addition, we have investigated the involvement of IFT proteins in the ciliogenesis of vertebrate photoreceptor cilia. Electron microscopy analyses revealed six morphologically distinct stages. The first stages are characterized by electron dense centriolar satellites and a ciliary vesicle, while the formation of a ciliary shaft and of the light sensitive outer segment disks are features of the later stages. IFT proteins were expressed during all stages of photoreceptor cell development and found to be associated with the ciliary apparatus. In addition to the centriole and basal body IFT proteins are present in the photoreceptor cytoplasm, associated with centriolar satellites, post-Golgi vesicles and with the ciliary vesicle. Therewith the data provide an evidence for the involvement of IFT proteins during ciliogenesis, including the formation of the ciliary vesicle and the elongation of the primary cilium of photoreceptor cells. Moreover, the cytoplasmic localization of IFT proteins in the absence of a ciliary shaft in early stages of ciliogenesis indicates roles of IFT proteins beyond their well-established function for IFT in mature cilia and flagella. rn

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Endothelial progenitor cells (EPC) play a fundamental role in tissue regeneration and vascular repair. Current research suggests that EPC are more resistant to oxidative stress as compared to differentiated endothelial cells. Here we hypothesized that EPC not only possess the ability to protect themselves against oxidative stress but also confer this protection upon differentiated endothelial cells by release of paracrine factors. To test this hypothesis, HUVEC incubated with conditioned medium obtained from early EPC cultures (EPC-CM) were exposed to H2O2 to assess the accumulation of intracellular ROS, extent of apoptosis and endothelial cell functionality. Under oxidative stress conditions HUVEC treated with EPC-CM exhibited substantially lower levels of intracellular oxidative stress (0.2+/-0.02 vs. 0.4+/-0.03 relative fluorescence units, p<0.05) compared to control medium. Moreover, the incubation with EPC-CM elevated the expression level of antioxidant enzymes in HUVEC (catalase: 2.6+/-0.4; copper/zinc superoxide dismutase (Cu/ZnSOD): 1.6+/-0.1; manganese superoxide dismutase (MnSOD): 1.4+/-0.1-fold increase compared to control, all p<0.05). Furthermore, EPC-CM had the distinct potential to reverse the functional impairment of HUVEC as measured by their capability to form tubular structures in vitro. Finally, incubation of HUVEC with EPC-CM resulted in a significant reduction of apoptosis (0.34+/-0.01 vs. 1.52+/-0.12 relative fluorescence units, p<0.01) accompanied by an increased expression ratio of the anti/pro-apoptotic factors Bcl-2/Bax to 2.9+/-0.7-fold (compared to control, p<0.05). Most importantly, neutralization of selected cytokines such as VEGF, HGF, IL-8 and MMP-9 did not significantly reverse the cyto-protective effect of EPC-CM (p>0.05), suggesting that soluble factors secreted by EPC, possibly via broad synergistic actions, exert strong cyto-protective properties on differentiated endothelium through modulation of intracellular antioxidant defensive mechanisms and pro-survival signals.