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Bourliva A, Aidona E, Papadopoulou L, Ferreira da Silva E, Patinha C, Sarafidis C, Kantiranis N. An integrated approach combining magnetic, geochemical and particle-based techniques to assess metal(loid) loadings in urban venues frequented by children. Sci Total Environ 2022; 822:153600. [PMID: 35121035 DOI: 10.1016/j.scitotenv.2022.153600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 01/28/2022] [Accepted: 01/28/2022] [Indexed: 06/14/2023]
Abstract
Urban venues frequented by children, such as playgrounds, are potentially important sources of exposure to anthropogenic metal(loids). Environmental quality of outdoor playgrounds is mainly assessed through direct geochemical monitoring, which is time-consuming and expensive. In this study we adapted a multidisciplinary approach combining magnetic measurements, geochemical analyses, particle-based techniques and bioaccessibility data so as to evaluate the applicability of magnetic methods as a low-cost and easy-to-use technology to monitor pollution level in public playgrounds. Playground sands were collected and their magnetic characteristics were studied in detail aiming to gain helpful additional details in relation to the type, concentration and particle-size distribution of the sand-bound magnetic particles. The obtained χlf values indicated an enhanced level of sand-bound magnetic components, while the dominant control of SSD grains on the magnetic load of playground-PG sands was revealed. Hysteresis parameters and thermomagnetic curves indicated low-coercivity ferrimagnetic minerals, such as magnetite and/or maghemite, as the predominant magnetic carriers. Ratios of χARM/χlf and χARM/SIRM indicated the dominance of coarser anthropogenic magnetic grains in the sampled PG sands compared to other recreational areas. Correlation analysis among magnetic variables and reported metal(loid) contents designated χARM as a more effective indicator for the detection of anthropogenic load in PG sand samples than χlf or SIRM. Simultaneously, through geochemical analyses in magnetic extracts separated from PG sands, metal(loid) contents were notably enriched in the magnetic fraction validating their strong affinity with sand-bound magnetic particles. Finally, bioaccessibility tests revealed lower UBM-extracted fractions for the magnetic extracts of PG sands compared to bulk samples. However, arsenic (As) was more bioaccessible in the sand-bound magnetic particles raising serious concerns for the children exposed to playground sands.
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Affiliation(s)
- A Bourliva
- Chemical Process and Energy Resources Institute, Centre for Research and Technology Hellas-CERTH, 6th km Charilaou-Thermi Rd, 57001 Thessaloniki, Greece; Department of Geophysics, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
| | - E Aidona
- Department of Geophysics, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - L Papadopoulou
- Department of Mineralogy-Petrology-Economic Geology, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, GREECE
| | - E Ferreira da Silva
- GeoBioTec, Department of Geoscience, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
| | - C Patinha
- GeoBioTec, Department of Geoscience, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
| | - C Sarafidis
- Laboratory of Physics, Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - N Kantiranis
- Department of Mineralogy-Petrology-Economic Geology, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, GREECE
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Bourliva A, Aidona E, Papadopoulou L, Ferreira da Silva E, Patinha C. Levels, oral bioaccessibility and health risk of sand-bound potentially harmful elements (PHEs) in public playgrounds: Exploring magnetic properties as a pollution proxy. Environ Pollut 2021; 290:118122. [PMID: 34500396 DOI: 10.1016/j.envpol.2021.118122] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 07/21/2021] [Accepted: 09/04/2021] [Indexed: 06/13/2023]
Abstract
Children in urban environments are exposed to potential harmful elements (PHEs) through variable exposure media. Playing activities in outdoor playgrounds have been considered of high concern due to children's exposure to sand-bound PHEs through unintentional or intentional sand ingestion. Furthermore, the affinity of magnetic particles with dust-bound PHEs in playgrounds has been reported. In this study, playground sands (PG sands) from public playgrounds in the city of Thessaloniki, N. Greece were sampled and the levels, the contamination degree, oral bioaccessibility and exposure assessment of PHEs were evaluated. In addition, low-cost and fast magnetic measurements (i.e. mass specific magnetic susceptibility, χlf) were explored as potential pollution and health risk proxies. Mineralogically, siliceous PG sands dominated, while morphologically angular magnetic particles and Fe-rich "spherules" of anthropogenic origin were revealed and verified by enhanced χlf values. The average total elemental contents exhibited a descending order of Mn > Ba > Cr > Zn > Ni > Pb > Cu > Co > As > Sn > Bi > Cd, however only Cd, Bi, Pb, Cr, As and Zn were presented anthropogenically enhanced. Notable increase on PHEs levels and finer sand fractions were observed with continuous sand use. Anthropogenically derived elements (i.e. Cd and Pb with high Igeo values) exhibited higher bioaccessible fractions in PG sands and considered easily soluble in gastric fluids through ingestion. However, increased risks were found for specific PHEs (especially Pb) only in a worst case exposure scenario of an intentional sand ingestion (pica disorder). Statistical analysis results revealed a linkage of anthropogenic components with sand-bound magnetic particles. Moreover, the recorded high affinity of Pb contents (in an enhanced magnetized sub-set of PG sands) and bioaccessible Cd fractions with χlf provide a preliminary indication on the successful applicability of low-cost and fast magnetic measurements in high impacted playground environments.
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Affiliation(s)
- A Bourliva
- Department of Geophysics, School of Geology, Aristotle University of Thessaloniki, Thessaloniki, 54124, Greece.
| | - E Aidona
- Department of Geophysics, School of Geology, Aristotle University of Thessaloniki, Thessaloniki, 54124, Greece
| | - L Papadopoulou
- Department of Mineralogy-Petrology-Economic Geology, School of Geology, Aristotle University of Thessaloniki, Thessaloniki, 54124, Greece
| | - E Ferreira da Silva
- GeoBioTec, Department of Geoscience, University of Aveiro, Campus de Santiago, Aveiro, 3810-193, Portugal
| | - C Patinha
- GeoBioTec, Department of Geoscience, University of Aveiro, Campus de Santiago, Aveiro, 3810-193, Portugal
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Christophoridis C, Bourliva A, Evgenakis E, Papadopoulou L, Fytianos K. Effects of anthropogenic activities on the levels of heavy metals in marine surface sediments of the Thessaloniki Bay, Northern Greece: Spatial distribution, sources and contamination assessment. Microchem J 2019. [DOI: 10.1016/j.microc.2019.104001] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Rigos AE, Dandoulaki C, Kontonasaki E, Kokoti M, Papadopoulou L, Koidis P. Effect of Immediate Dentin Sealing on the Bond Strength of Monolithic Zirconia to Human Dentin. Oper Dent 2019; 44:E167-E179. [DOI: 10.2341/18-198-l] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
SUMMARY
Objective:
This study evaluated the shear bond strength (SBS) of pretreated monolithic zirconia surfaces bonded to human dentin following immediate dentin sealing (IDS) using two different self-adhesive resin luting agents.
Methods and Materials:
Sixty intact human third molars were collected, stored, sectioned appropriately, and molded according to ISO 29022:2013, resulting in 120 dentin specimens. Ceramic cylindrical specimens were fabricated using CAD/CAM technology and sintered as recommended (final bonding area A=2.56 mm2). Specimens were randomly assigned to eight groups (15≥n≥14) depending on dentin conditioning method (IDS or delayed dentin sealing [DDS]), zirconia surface pretreatment (airborne particle abrasion [APA] with 50 μm Al2O3 particles at 3 bar for 10 seconds or tribochemical silica coating [TBC] with 30 μm CoJet particles at 2.8 bar for 10 seconds), and adhesive luting agent type (Panavia F2.0 [PAN] or PermaCem Dual Smartmix [PER]). Bonded specimens were water-stored (37°C, 24 hours) and subjected to SBS testing (50-kgF load cell, 1 mm/min). Fracture type was evaluated with stereomicroscopy. Data (MPa) were statistically analyzed using three-way analysis of variance (α=0.05).
Results:
All factors significantly affected SBS values (p<0.001). Dentin conditioning method presented the greatest effect. Mean SBS values ranged from 12.603 MPa (PER-APA-DDS) to 40.704 MPa (PER-TBC-IDS). Based on the fracture type, adhesive failures at the luting agent–zirconia interface were the least common.
Conclusion:
Bonding strategies for monolithic zirconia restorations could potentially benefit from IDS, regardless of the adhesive luting agent system used.
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Affiliation(s)
- AE Rigos
- Athanasios E Rigos, Doctor of Dental Surgery, Department of Dentistry, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - C Dandoulaki
- Chrysoula Dandoulaki, DDS, Prosthodontics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - E Kontonasaki
- Eleana Kontonasaki, DDS, MSc, PhD, Prosthodontics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - M Kokoti
- Maria Kokoti, DDS, PhD, Prosthodontics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - L Papadopoulou
- Lambrini Papadopoulou, BSc, MSc, PhD, Mineralogy-Petrology-Economic Geology, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - P Koidis
- Petros Koidis, DDS, MS, PhD, Prosthodontics, Aristotle University of Thessaloniki Prosthodontics, Thessaloniki, Greece
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Bourliva A, Kantiranis N, Papadopoulou L, Aidona E, Christophoridis C, Kollias P, Evgenakis M, Fytianos K. Seasonal and spatial variations of magnetic susceptibility and potentially toxic elements (PTEs) in road dusts of Thessaloniki city, Greece: A one-year monitoring period. Sci Total Environ 2018; 639:417-427. [PMID: 29800837 DOI: 10.1016/j.scitotenv.2018.05.170] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 04/19/2018] [Accepted: 05/11/2018] [Indexed: 06/08/2023]
Abstract
A one-year sampling campaign of road dusts was carried out at 10 distinct sites in the broader area of the city of Thessaloniki, Greece and concentrations of heavy metals (HMs) along with magnetic susceptibility were evaluated. The concentrations of HMs in road dusts were higher than their local background values, while magnetic parameters indicated a significant anthropogenic load. Principal component analysis (PCA) identified non-exhaust vehicular emissions, oil/fuel combustion and industrial activities as major sources of heavy metals accounted for approximately 73% of the total variance. A significant seasonal variability for Cr, Cu, Mn, and χlf was observed with constantly higher values during summer. Moreover, variations among urban and industrial sites were more pronounced for Cr, Cu, Zn, and χlf, while they displayed insignificant variations across all urban sites. On the contrary, concentration peaks in the urban cluster were observed for Cd, Mn, and Ni coinciding with the port area. Based on multiple pollution indices, a severe polluted area was revealed, while potential ecological risk index (RI) indicated a high potential ecological risk with Cd being regarded as the pollutant of high concern. The health risk assessment model indicated ingestion as the major exposure pathway. For both adults and children, Cr and Pb had the highest risk values, mainly recorded in the urban cluster underscoring the need of potential measures to reduce road dust in urban environments.
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Affiliation(s)
- A Bourliva
- Department of Mineralogy-Petrology-Economic Geology, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
| | - N Kantiranis
- Department of Mineralogy-Petrology-Economic Geology, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - L Papadopoulou
- Department of Mineralogy-Petrology-Economic Geology, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - E Aidona
- Department of Geophysics, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - C Christophoridis
- Environmental Pollution Control Laboratory, Chemistry Department, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - P Kollias
- Department of Meteorology-Climatology, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - M Evgenakis
- Environmental Pollution Control Laboratory, Chemistry Department, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - K Fytianos
- Environmental Pollution Control Laboratory, Chemistry Department, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
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Pandoleon P, Kontonasaki E, Kantiranis N, Pliatsikas N, Patsalas P, Papadopoulou L, Zorba T, Paraskevopoulos KM, Koidis P. Aging of 3Y-TZP dental zirconia and yttrium depletion. Dent Mater 2017; 33:e385-e392. [PMID: 28789858 DOI: 10.1016/j.dental.2017.07.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 05/03/2017] [Accepted: 07/11/2017] [Indexed: 02/04/2023]
Abstract
OBJECTIVE Yttrium-stabilized zirconia is susceptible to low temperature degradation after interaction with water. Various mechanisms by which water molecules destabilize the tetragonal phase have been proposed, while the concept of yttrium depletion by the incorporation of hydroxyl ions in the crystalline structure either through the formation of YOH/ZrOH bonds or small α-Y(OH)3 crystallites, is prevailing. The present study was performed to investigate the surface alterations on a 3Y-TZP dental ceramic during the process of in-vitro aging and to further explore the yttrium depletion mechanism that occurs upon interaction with water. METHODS Surface structural changes of zirconia specimens where investigated before and after in-vitro aging with X-ray diffraction analysis, Fourier-transformed infrared spectroscopy, X-ray photoelectron spectroscopy, fluorescence microscopy and scanning electron microscopy. RESULTS High luminescence generated from the non-aged specimen was explained by the high amount of oxygen vacancies. The phase transformation from the t-ZrO2 to the m-ZrO2 phase after aging was accompanied by a significant loss of yttrium, a clear decrease of oxygen vacancies and a profound decrease of luminescence. Surface oxygen vacancies either migrated into the inner of the specimens or/and/engaged oxygen from the ZrO2 and formed the metallic phase of Y2O3 on the surface after aging. SIGNIFICANCE An "ideal" amount of oxygen vacancies that could stabilize the tetragonal phase in Y-TZP zirconia ceramics, without compromising esthetics and LTD resistance, is still a matter of further research and different susceptibilities to LTD among various dental zirconia ceramics are based on the amount of oxygen vacancies that can be annihilated by water molecules.
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Affiliation(s)
- P Pandoleon
- Faculty of Dentistry, Department of Prosthodontics, School of Health Sciences, Aristotle University of Thessaloniki, GR-54124, Thessaloniki, Greece
| | - E Kontonasaki
- Faculty of Dentistry, Department of Prosthodontics, School of Health Sciences, Aristotle University of Thessaloniki, GR-54124, Thessaloniki, Greece
| | - N Kantiranis
- Department of Mineralogy-Petrology-Economic Geology, Aristotle University of Thessaloniki, GR-54124, Thessaloniki, Greece
| | - N Pliatsikas
- Department of Physics, Aristotle University of Thessaloniki, GR-54124, Thessaloniki, Greece
| | - P Patsalas
- Department of Physics, Aristotle University of Thessaloniki, GR-54124, Thessaloniki, Greece
| | - L Papadopoulou
- Department of Mineralogy-Petrology-Economic Geology, Aristotle University of Thessaloniki, GR-54124, Thessaloniki, Greece
| | - T Zorba
- Department of Physics, Aristotle University of Thessaloniki, GR-54124, Thessaloniki, Greece
| | - K M Paraskevopoulos
- Department of Physics, Aristotle University of Thessaloniki, GR-54124, Thessaloniki, Greece
| | - P Koidis
- Faculty of Dentistry, Department of Prosthodontics, School of Health Sciences, Aristotle University of Thessaloniki, GR-54124, Thessaloniki, Greece.
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Papadopoulos A, Koroneos A, Christofides G, Papadopoulou L, Tzifas I, Stoulos S. Assessment of gamma radiation exposure of beach sands in highly touristic areas associated with plutonic rocks of the Atticocycladic zone (Greece). J Environ Radioact 2016; 162-163:235-243. [PMID: 27280859 DOI: 10.1016/j.jenvrad.2016.05.035] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Revised: 05/28/2016] [Accepted: 05/31/2016] [Indexed: 06/06/2023]
Abstract
This study aims to evaluate the activity concentrations of 238U, 226Ra, 232Th, 228Th and 40K along beaches close to the plutonic rocks of the Atticocycladic zone that ranged from 15 to 628, 12-2292, 16-10,143, 14-9953 and 191-1192 Bq/kg respectively. A sample from island of Mykonos contained the highest 232Th content measured in sediments of Greece. The heavy magnetic fraction and the heavy non-magnetic fraction as well as the total heavy fraction, were correlated with the concentrations of the measured radionuclides in the bulk samples. The heavy fractions seem to control the activity concentrations of 238U and 232Th of all the samples, showing some local differences in the main 238U and 232Th mineral carrier. Similar correlations have been found between 238U, 232Th content and rare earth elements concentrations. The measured radionuclides in the beach sands were normalized to the respective values measured in the granitic rocks, which at least in most cases are their most probable parental rocks, so as to provide data upon their enrichment or depletion. Since the Greek beaches are among the most popular worldwide the annual effective dose equivalent received due to sand exposure has been estimated and found to vary between 0.002 and 0.379 mSv y-1 for tourists and from 0.018 to 3.164 mSv y-1 for local people working on the beach. The values corresponding to ordinary sand samples are orders of magnitude lower than the limit of 1 mSv y-1, only in the case of heavy minerals-rich sands the dose could reach or exceed the recommended maximum limit.
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Affiliation(s)
- A Papadopoulos
- Department of Mineralogy, Petrology and Economic Geology, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
| | - A Koroneos
- Department of Mineralogy, Petrology and Economic Geology, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - G Christofides
- Department of Mineralogy, Petrology and Economic Geology, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - L Papadopoulou
- Department of Mineralogy, Petrology and Economic Geology, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - I Tzifas
- School of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - S Stoulos
- Laboratory of Nuclear Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
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Kontonasaki E, Bakopoulou A, Theocharidou A, Theodorou GS, Papadopoulou L, Kantiranis N, Bousnaki M, Chatzichristou C, Papachristou E, Paraskevopoulos K, Koidis P. Effective Cell Growth Potential of Mg-Based Bioceramic Scaffolds towards Targeted Dentin Regeneration. Balkan Journal of Dental Medicine 2015. [DOI: 10.1515/bjdm-2015-0039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
SUMMARY
New emerging approaches in tissue engineering include incorporation of metal ions involved in various metabolic processes, such as Cu, Zn, Si into bioceramic scaffolds for enhanced cell growth and differentiation of specific cell types. The aim of the present work was to investigate the attachment, morphology, growth and mineralized tissue formation potential of Dental Pulp Stem Cells (DPSCs) seeded into Mg-based glassceramic scaffolds with incorporated Zn and Cu ions. Bioceramic scaffolds containing Si 60%, Ca 30%, Mg 7.5% and either Zn or Cu 2.5%, sintered at different temperatures were synthesized by the foam replica technique and seeded with DPSCs for up to 21 days. Scanning Electron Microscopy with associated Energy Dispersive Spectroscopy (SEM-EDS) was used to evaluate their ability to support the DPSCs’s attachment and proliferation, while the structure of the seeded scaffolds was investigated by X-Ray Diffraction Analysis (XRD). Zn-doped bioceramic scaffolds promoted the attachment and growth of human DPSCs, while identically fabricated scaffolds doped with Cu showed a cytotoxic behaviour, irrespective of the sintering temperature. A mineralized tissue with apatite-like structure was formed on both Cu-doped scaffolds and only on those Zn-doped scaffolds heat-treated at lower temperatures. Sol-gel derived Zn-doped scaffolds sintered at 890oC support DPSC growth and apatite-like tissue formation, which renders them as promising candidates towards dental tissue regeneration.
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Affiliation(s)
- E. Kontonasaki
- School of Dentistry, Department of Fixed Prosthesis and Implant Prosthodontics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - A. Bakopoulou
- School of Dentistry, Department of Fixed Prosthesis and Implant Prosthodontics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - A. Theocharidou
- School of Dentistry, Department of Fixed Prosthesis and Implant Prosthodontics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - G. S. Theodorou
- Faculty of Sciences, Department of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - L. Papadopoulou
- Faculty of Sciences, Department of Geology, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - N. Kantiranis
- Faculty of Sciences, Department of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - M. Bousnaki
- School of Dentistry, Department of Fixed Prosthesis and Implant Prosthodontics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - C. Chatzichristou
- School of Dentistry, Department of Fixed Prosthesis and Implant Prosthodontics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - E. Papachristou
- School of Dentistry, Department of Fixed Prosthesis and Implant Prosthodontics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - K.M. Paraskevopoulos
- Faculty of Sciences, Department of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - P. Koidis
- School of Dentistry, Department of Fixed Prosthesis and Implant Prosthodontics, Aristotle University of Thessaloniki, Thessaloniki, Greece
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Iliadis C, Papoulia F, Papadopoulou L, Kournioti A, Panou A, Georgoudi A. PR54 Alcohol and breast cancer in young women. Breast 2014. [DOI: 10.1016/s0960-9776(14)70064-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Zougrou IM, Katsikini M, Pinakidou F, Paloura EC, Papadopoulou L, Tsoukala E. Study of fossil bones by synchrotron radiation micro-spectroscopic techniques and scanning electron microscopy. J Synchrotron Radiat 2014; 21:149-160. [PMID: 24365930 DOI: 10.1107/s1600577513025228] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Accepted: 09/11/2013] [Indexed: 06/03/2023]
Abstract
Earlymost Villafranchian fossil bones of an artiodactyl and a perissodactyl from the Milia excavation site in Grevena, Greece, were studied in order to evaluate diagenetic effects. Optical microscopy revealed the different bone types (fibro-lamellar and Haversian, respectively) of the two fragments and their good preservation state. The spatial distribution of bone apatite and soil-originating elements was studied using micro-X-ray fluorescence (µ-XRF) mapping and scanning electron microscopy. The approximate value of the Ca/P ratio was 2.2, as determined from scanning electron microscopy measurements. Bacterial boring was detected close to the periosteal region and Fe bearing oxides were found to fill bone cavities, e.g. Haversian canals and osteocyte lacunae. In the perissodactyl bone considerable amounts of Mn were detected close to cracks (the Mn/Fe weight ratio takes values up to 3.5). Goethite and pyrite were detected in both samples by means of metallographic microscopy. The local Ca/P ratio determined with µ-XRF varied significantly in metal-poor spots indicating spatial inhomogeneities in the ionic substitutions. XRF line scans that span the bone cross sections revealed that Fe and Mn contaminate the bones from both the periosteum and medullar cavity and aggregate around local maxima. The formation of goethite, irrespective of the local Fe concentration, was verified by the Fe K-edge X-ray absorption fine structure (XAFS) spectra. Finally, Sr K-edge extended XAFS (EXAFS) revealed that Sr substitutes for Ca in bone apatite without obvious preference to the Ca1 or Ca2 unit-cell site occupation.
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Affiliation(s)
- I M Zougrou
- School of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - M Katsikini
- School of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - F Pinakidou
- School of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - E C Paloura
- School of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - L Papadopoulou
- School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - E Tsoukala
- School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
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Papadopoulos A, Christofides G, Koroneos A, Papadopoulou L, Papastefanou C, Stoulos S. Natural radioactivity and radiation index of the major plutonic bodies in Greece. J Environ Radioact 2013; 124:227-38. [PMID: 23827232 DOI: 10.1016/j.jenvrad.2013.06.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 05/22/2013] [Accepted: 06/09/2013] [Indexed: 05/14/2023]
Abstract
The natural radioactivity of the major plutonic bodies in Greece, as well as the assessment of any potential health hazard due to their usage as decorative building materials is studied. One hundred and twenty one samples from every major plutonic body in Greece, including various rock-types from gabbro to granite, have been measured for their natural radioactivity using γ-spectrometry methodology. According to the experimental results, the natural radioactivity levels were ranged up to 315 Bq kg(-1) for (226)Ra, up to 376 Bq kg(-1) for (232)Th and up to 1632 Bq kg(-1) for (40)K, with arithmetic mean values and standard deviations of 74 (±51), 85 (±54) and 881 (±331) Bq kg(-1) respectively, which are below the international representative mean values for granite stones. The excess on the effective dose received annually indoors due to granite tiles usage is estimated considering a standard room model where granite tiles with 1.5 cm in thickness cover only the floor of the room. The increment on the external γ-radiation effective dose rate shows a Gaussian distribution well dispersed below 0.3 mSv y(-1), presenting a mean value of 0.14 (±0.06) mSv y(-1). In case of the internal α-radiation a log-normal distribution is appeared scattering below 0.5 mSv y(-1) with a mean value 0.19 (±0.13) mSv y(-1), for a well-ventilated living environment. In case of a poor-ventilated room the increment on internal effective dose rate is estimated with a mean value 0.27 (±0.19) mSv y(-1) scattering below 0.8 mSv y(-1). The majority of the samples increase the external as well as the internal dose less than 30% of the maximum permitted limit of the effective dose rate. Therefore, at least from radiological point of view, the plutonic rocks of Greece could be safely used as decorative building materials.
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Affiliation(s)
- A Papadopoulos
- Department of Mineralogy, Petrology and Economic Geology, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
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Sarri S, Misaelides P, Noli F, Papadopoulou L, Zamboulis D. Removal of iodide from aqueous solutions by polyethylenimine-epichlorohydrin resins. J Radioanal Nucl Chem 2013. [DOI: 10.1007/s10967-013-2662-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Roumeli E, Goudouri OM, Yoganand CP, Papadopoulou L, Kantiranis N, Selvarajan V, Paraskevopoulos KM. Study of the Bioactive Behavior of Hydroxyapatite/SiO₂CaOMgO Glass-Ceramics Synthesized by Transferred Arc Plasma (TAP). ACTA ACUST UNITED AC 2011. [DOI: 10.4303/bda/d110153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- E. Roumeli
- Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - O. M. Goudouri
- Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - C. P. Yoganand
- Plasma Laboratory, Department of Physics, Bharathiar University, Coimbatore-46, India
| | - L. Papadopoulou
- Department of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - N. Kantiranis
- Department of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - V. Selvarajan
- Plasma Laboratory, Department of Physics, Bharathiar University, Coimbatore-46, India
| | - K. M. Paraskevopoulos
- Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
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Theodorou G, Goudouri OM, Kontonasaki E, Chatzistavrou X, Papadopoulou L, Kantiranis N, Paraskevopoulos KM. Comparative Bioactivity Study of 45S5 and 58S Bioglasses in Organic and Inorganic Environment. ACTA ACUST UNITED AC 2011. [DOI: 10.4303/bda/d110154] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- G. Theodorou
- Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - O. M. Goudouri
- Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - E. Kontonasaki
- Department of Fixed Prosthodontics, School of Dentistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - X. Chatzistavrou
- Department of Materials, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | - L. Papadopoulou
- Department of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - N. Kantiranis
- Department of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - K. M. Paraskevopoulos
- Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
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Hatzistavrou E, Chatzistavrou X, Papadopoulou L, Kantiranis N, Kontonasaki E, Boccaccini A, Paraskevopoulos K. Characterisation of the bioactive behaviour of sol–gel hydroxyapatite–CaO and hydroxyapatite–CaO–bioactive glass composites. Materials Science and Engineering: C 2010. [DOI: 10.1016/j.msec.2010.01.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Kontonasaki E, Sivropoulou A, Papadopoulou L, Garefis P, Paraskevopoulos K, Koidis P. Attachment and proliferation of human periodontal ligament fibroblasts on bioactive glass modified ceramics. J Oral Rehabil 2007; 34:57-67. [PMID: 17207079 DOI: 10.1111/j.1365-2842.2006.01622.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
In this study, six groups of modified ceramic specimens were constructed and were studied comparatively with dental porcelain (P:control) for their ability to support human periodontal ligament fibroblasts attachment and proliferation. The dental porcelain was initially coated with bioactive glass (PCB) or with a mixture of porcelain and bioactive glass (PCBP) and then calcium-phosphate rich (Ca-P) or hydroxy-carbonate apatite (HCAp) layers were bio-mimetically developed on both surfaces (PCB and PCBP) after immersion in simulated body fluid. The development and characterization of Ca-P and HCAp layers on PCBCa-P, PCBHCAp, PCBPCa-P, PCBPHCAp specimens' surfaces were evaluated by Scanning Electron Microscopy (SEM) and further confirmed by Fourier Transform Infrared Spectroscopy (FTIR). The modified ceramics differed from their controls concerning their surface morphology as evaluated by SEM, and their surface chemical composition (Al, P, Si, Ca, Na and K) as evaluated by Energy Dispersive Spectroscopy (EDS). Almost all modified specimens supported cell attachment, spreading and proliferation at higher extent than the control porcelain specimens. The additional layers of Ca-P or HCAp on PCBP and PCB specimens were found to positively affect cell attachment and proliferation. The highest cell population, of all specimens tested, was observed on PCBPCa-P and PCBPHCAp. The Ca-P particles present on all Ca-P and HCAp coated specimens seemed to be involved in cell adhesion.
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Affiliation(s)
- E Kontonasaki
- Department of Fixed Prosthesis and Implant Prosthodontics, School of Dentistry, Aristotle University Thessaloniki, Thessaloniki, Greece
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Gotsis A, Bozia P, Dourtsiou S, Labrou A, Papadopoulou L, Savvopoulou A, Borghi L, Theodoridis D, Karras S, Panagiotidou A. We-P11:36 Impaired glucose metabolism in patients with newly diagnosed coronary artery disease. ATHEROSCLEROSIS SUPP 2006. [DOI: 10.1016/s1567-5688(06)81392-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Georgantzi B, Papadopoulou L, Zorba T, Garefis P, Paraskevopoulos K, Koidis P. Development of HydroxyCarbonate Apatite on hybrid polymers used in fixed restorations modified by bioactive glass. ACTA ACUST UNITED AC 2004. [DOI: 10.1002/pssa.200306761] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Abstract
Restorative dental materials are considered biocompatible without exhibiting any bioactive behaviour. The aim of this study was the investigation of surface structure changes on conventional dental ceramics used in metal-ceramic restorations modified by a bioactive glass, after immersion in SBF for various time periods. Bioactive glass powder was mixed with porcelain powder with three different weight ratios: 1:1, 1:2, and 2:1. The two powders were mixed with porcelain modelling liquid and the mixture was transferred and spread on the surface of pre-fabricated ceramic disks. Coated ceramic specimens after being exposed to a specific thermal cycle as it is recommended for dental ceramics were soaked in Simulated Body Fluid (SBF) at 37 degrees C for various periods of time. After soaking, specimens were studied using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). Results revealed the development of a non-stoichiometric, biological apatite layer on their surface after exposure in SBF for several time periods. The onset of apatite-layer formation is directly dependent on the amount of bioglass in the coating and its thickness reduces within the specimens of the same bioactive glass-porcelain proportion with time, reaching an average thickness of 15 microm at the longest immersion time, for all the specimens.
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Affiliation(s)
- E Kontonasaki
- Department of Fixed Prosthesis and Implants Prosthodontics, Aristotle University of Thessaloniki, Dental School, Thessaloniki, Aristotle University of Thessaloniki, Thessaloniki, Greece
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Papadopoulou L, Kontonasaki E, Zorba T, Chatzistavrou X, Pavlidou E, Paraskevopoulos K, Sklavounos S, Koidis P. Dental ceramics coated with bioactive glass: Surface changes after exposure in a simulated body fluid under static and dynamic conditions. ACTA ACUST UNITED AC 2003. [DOI: 10.1002/pssa.200306588] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Kontonasaki E, Zorba T, Papadopoulou L, Pavlidou E, Chatzistavrou X, Paraskevopoulos K, Koidis P. Hydroxy Carbonate Apatite Formation on Particulate Bioglass In Vitro as a Function of Time. Cryst Res Technol 2002. [DOI: 10.1002/1521-4079(200211)37:11<1165::aid-crat1165>3.0.co;2-r] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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