Vinča Institute of Nuclear Sciences
Repository of the Vinča Institute of Nuclear Sciences (VinaR)Not a member yet
15953 research outputs found
Sort by
Synthesis and structural properties of europium-doped fluorapatite nanoparticles as a promising luminescent biomaterial
No full textEuropium-doped fluorapatite Ca10-x(PO4)6F2:xEu3+ (x = 0.05, 0.1 and 0.5) nanoparticles were successfully synthesised by a coprecipitation method at room temperature and calcination at 700°C. Characterisation of samples using XRD, TEM, TGA-DTA, FTIR and photoluminescence spectroscopy showed that the obtained calcium deficient fluorapatite nanoparticles exhibit a high degree of crystalline disorder, i.e. Eu doping leads to a remarkable structural amorphisation of fluorapatite. The crystallinity and crystallite size of the obtained samples decreased with the increase of Eu doping. The lattice parameters of the calcined samples decrease noticeably with the increase in Eu3+ dopant concentration. When excited by UV radiation at 393 nm, all europium-doped fluorapatite samples showed the characteristic 5D0-7F0-4 emission lines of Eu3+ ions. According to the luminescence results, the Eu3+ ions have largely replaced the Ca2+ ions in the Ca(I) position in the crystal lattice of the fluorapatite
Computational Study of Interfacial Charge-Transfer Complexes Between ZnO and Thiol Analogs of Catechol
No full textInterfacial charge-transfer (ICT) complexes provide an effective strategy for extending the optical absorption of wide-bandgap oxides into the visible spectrum, a key requirement for enhancing photo-driven reactions. In this work, density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations were employed to investigate the ICT complexes formed between ZnO nanoparticles and benzene derivatives, specifically catechol (CAT), 2-mercaptophenol (2-MP), and 1,2-benzenedithiol (1,2-BDT). The results show that ZnO complexes with catechol and 2-mercaptophenol display ICT transitions in the visible region, whereas the 1,2-benzenedithiol complex primarily absorbs in the ultraviolet range. This behavior is attributed to differences in Zn─O and Zn─S bonding interactions, with sulfur-containing ligands forming stronger bonds. Nevertheless, the absorptions of 2-MP/ZnO and 1,2-BDT/ZnO are blue-shifted compared to the CAT/ZnO system. Further modifications, such as ligand substitutions, could be necessary to optimize absorption near the solar spectrum's peak. Therefore, a crucial aspect of this study is the assessment of two sulfur-containing analogs of catechol, a well-established ligand for use in ICT-based applications. © 2025 Wiley-VCH GmbH
Prognostic and Predictive Significance of Microsatellite Status in Patients with Colorectal Cancer in Stage II and Stage III Disease: Single-Centre Experience
No full textBackground: Colorectal cancer (CRC) is one of the leading causes of cancer-related morbidity and mortality worldwide. Microsatellite instability (MSI) is a crucial biomarker with prognostic and predictive value, influencing treatment decisions in CRC. Methods: This retrospective study investigated the impact of the MSI status on clinical outcomes in 184 CRC patients treated at the Oncology Institute of Vojvodina between 2018 and 2023. The MSI status was determined using the immunohistochemical analysis of mismatch repair proteins. Results: Among the cohort, 75% of tumors were microsatellite-stable (MSS), 4.3% exhibited low MSI (MSI-L), and 20.6% displayed high MSI (MSI-H). MSI-H tumors were significantly associated with right-sided CRC, mucinous differentiation, and female gender (p<0.05). The survival analyses revealed that the MSI-H patients with stage II disease had significantly better disease-free survival (DFS) and overall survival (OS) than the MSS counterparts (p=0.024 and p=0.006, respectively). Conversely, the MSI-H status in stage II patients receiving adjuvant therapy was linked to shorter DFS (p=0.000), highlighting the limited benefit from 5-fluorouracil-based regimens. In stage III CRC, the MSI status did not significantly affect DFS or OS. Conclusion: These findings underscore the dual role of MSI as a favorable prognostic marker in early-stage CRC and a predictor of the reduced benefit from adjuvant chemotherapy in stage II disease. This study emphasizes the need for individualized treatment strategies based on the MSI status and supports the potential integration of immunotherapy in the adjuvant setting for MSI-H CRC. © 2025, Institute of Oncology Sremska Kamenica. All rights reserved
Heat triggered structural transformation of SiO2 coated akaganeite nanoparticles: ε-Fe2O3 phase formation
No full textOrthorhombic epsilon iron oxide polymorph ε-Fe2O3 still attracts extensive research interest due to its interesting magnetic properties and potential applications in high-density data storage and high-frequency millimeter electromagnetic waves shielding. The present paper reports on the fabrication of ε-Fe2O3 polymorph through thermal treatment of silica coated akaganeite nanoparticles using various heating protocols. Morphology, structure and magnetic properties of the resulting samples were assessed by various experimental techniques. Transmission electron microscopy (TEM) of the four samples calcined at temperatures above 900 °C showed that the obtained particles were roughly oval in shape with average particle diameters (DTEM), in the range from 13 nm to 23 nm. The X-ray diffractometry confirmed presence of prevailing ε-Fe2O3 phase with addition of α-Fe2O3 phase whose amount depended on the heating regime used. The saturation magnetization, Ms, values were in the range 9.5–11.6 Am2/kg, while the room temperature (RT) coercivity fields, Hc, ranged from 111.4 kA/m (1.4 kOe) to 1002.7 kA/m (12.6 kOe). The highest Ms and Hc were achieved in the sample heated up to 930 °C through several dwelling steps at different temperatures, while another sample also annealed at 930 °C but using different heating path, displayed substantially lower coercivity Hc = 628.7 kA/m (7.9 kOe). Annealing at higher final temperatures 940 °C and 1000 °C also did not improve coercivity due to increased number of superparamagnetic particles. Presented results emphasize importance of different parameters involved in the process of thermal treatment of epsilon iron oxide precursor samples. It was demonstrated that magnetic properties of the ε-Fe2O3 polymorph prepared from silica coated akaganeite nanoparticles can be tuned by employing a multistep heating protocol with carefully chosen dwelling temperatures and times. © 2025 Elsevier Masson SA
Implication of p16 Promoter Methylation, the BRAFV600E Mutation, and ETS1 Expression Determination on Papillary Thyroid Carcinoma Prognosis and High-Risk Patients’ Selection
No full textBackground/Objectives: Papillary thyroid carcinoma (PTC) is the most common malignancy of the endocrine system, characterized by various molecular alterations. This study evaluates the relationship between p16 promoter methylation status, BRAFV600E mutation presence, and ETS1 (E26 transformation-specific) expression, aiming to better understand their clinical significance and to enhance the risk stratification of PTC patients. Methods: p16 promoter methylation was analyzed by methylation-specific PCR (MSP), BRAFV600E by mutant allele-specific PCR amplification (MASA), ETS1 mRNA expression by quantitative PCR (qPCR), ETS1 protein expression by immunohistochemistry (IHC), and Western blot. All tested factors were further associated with the occurrence of unfavorable clinicopathological data of the patients. Results: While p16 methylation did not correlate with adverse clinical parameters or BRAFV600E mutation presence, it was significantly associated with the increased ETS1 mRNA levels. Combined p16 methylation with high ETS1 protein levels was significantly associated with advanced pT and pTNM stages. BRAFV600E-mutated PTC cases with p16 methylation showed increased mRNA and protein ETS1 expression. Conclusions: Therefore, although p16 methylation could not be used as a standalone prognostic marker, its association with elevated ETS1 levels points to its potential involvement in tumor progression and adverse clinical outcomes, particularly in BRAFV600E-mutated PTCs. Deeper insights into these interactions may enhance PTC prognosis and the selection of high-risk patients
Machine Learning-Assisted Development of Injectable, Mechanically Robust, and Energy Metabolism-Modulating Brushite Cements
No full textIn orthopedic minimally invasive surgeries (MIS) such as percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP), calcium phosphate cements (CPCs) are an attractive alternative to bioinert polymethyl methacrylate (PMMA) due to their superior biocompatibility and osteoconductivity. However, the mechanical strength and injectability of CPCs often remain insufficient for load-bearing applications, limiting their broader use in these critical procedures. To address this challenge, we introduce a machine learning-assisted approach to enhance both the mechanical strength and injectability of CPCs by identifying specific polymers as superplasticizers. By optimizing its concentration and the liquid-to-powder (L/P) ratio, we developed an injectable brushite-based cement with an exceptional compressive strength of 79.5 ± 4.3 MPa, surpassing both traditional CPCs and PMMA in orthopedic applications. Zeta potential and adsorption studies reveal that these superplasticizers enhance cement paste dispersion via electrostatic repulsion. In vitro assays demonstrate excellent biocompatibility and osteogenic properties, while in vivo experiments further confirm the cement’s superior osteoinductive capability. The brushite cement regulates cellular metabolism and stem cell differentiation by enhancing energy metabolism and activating key signaling pathways such as phosphatidylinositol 3-kinase–AKT and mitogen-activated protein kinase–extracellular signal–regulated kinase. These findings offer a novel approach to fabricating CPCs with enhanced mechanical strength and osteogenic potential, addressing long-standing challenges in orthopedic MIS
Ion-doped mesoporous bioactive glass particles as ciprofloxacin drug delivery vehicles
No full textIn recent years, sol-gel derived mesoporous bioactive glass particles (MBGs) have gained significant attention due to their highly tunable surface properties, which allow for high surface area and large pore volume, key features for applications in regenerative medicine and drug delivery systems. The incorporation of therapeutic ions presents a promising strategy to stimulate specific biological responses and promote tissue regeneration. Additionally, the presence of dopants can influence the mesoporosity, hence affecting drug delivery performance. This study aimed to investigate the influence of binary and multi-ion doping on the surface properties and drug delivery capacity of MBGs. A modified microemulsion-assisted sol-gel synthesis method was utilized to prepare the particles co-doped with Sr and Mg ions (denoted as SrMg-MBGs) and multi-doped with Sr,Mg,Cu,Zn ions (referred to mMBGs). The obtained particles were subsequently analyzed for their morphological and surface characteristics, and their capacity for ciprofloxacin drug loading and release. Brunauer-Emmett-Teller (BET) analysis revealed that binary doping only slightly increased volume of mesopores (Vmeso) and micropores (Vmicro), while multi-doping significantly increased Vmicro and specific surface area (SSA). High-Resolution Transmission Electron Microscopy (HR-TEM) revealed that doping significantly influences pore size and morphology. Additionally, synthesis parameters of MBGs were found to influence particle size and porosity, leading to marked increase in SSA. UV-Vis spectroscopy analysis were employed to determine drug loading capacity and release behavior, and it was found that ion-doping had a significant impact on drug loading capacity. Overall, this study highlights the potential of doped MBGNs as drug delivery systems, and underscores the need for further research into their application in targeted therapeutics.Programme and the Book of Abstracts / 8th Conference of The Serbian Society for Ceramic Materials, 8CSCS-2025, June 14-16, 2025, Belgrade, Serbia
Chitosan Polymers: Their Blends, IPNs, Gels, and Composites Membranes for Water Purification
No full textChitosan is a partially deacetylated derivative of chitin with a linear chain structure built from two different monomers, N -acetyl-glucosamine and glucosamine. Due to its biocompatibility, biodegradability, and non-toxicity, chitosan has attracted great scientific and industrial interest for its potential applications in numerous fields. Especially interesting are chitosan’s adsorbing properties for water purification treatments, which have emerged as a crucial topic for modern society. The presence of a considerable amount of hydroxyl and amino functional groups in the structure of chitosan makes this biopolymer a great candidate for the removal of various pollutants from water. On the other hand, its low mechanical strength, relatively low surface area, and large swelling percent in water are major drawbacks for its application on a large scale. In this chapter, we present the latest major achievements in the application of chitosan and chitosan-based composites for water purification. © 2025 WILEY-VCH GmbH
Quantitative Analysis of Mechanically Alloyed CuZrB Powders
No full textCopper matrix composites are proving to be a suitable match for the present engineering needs of the market where higher temperature resistance and good microstructural stability are required. Powder metallurgy technique was used to procure the powder mixture, Cu-2Zr-0.6B (wt.%). Different mechanical alloying (MA) parameters were examined with the main focus on time, ranging from 10 h to 40 h. SEM analysis was employed to determine structural and morphological changes of the mechanically alloyed powder mixture. MIPAR image analysis software was used to complete the quantitative analysis of the mechanically alloyed CuZrB powders. Changes in size and shape of powder particles were determined during up to 40 h of MA with key points after every 10 h. It was concluded that the powder particle size decreases as the MA time increases. With the increase in MA time the area of each particle decreases due to the dominant plastic deformation mechanisms as particles undergo high forces through ball-particle-ball and wall-particle-ball collisions during the MA process
The importance of monitoring radioactivity in surface waters downstream from nuclear power plants
No full textRadioactivity monitoring in the Republic of Serbia is defined by Law on Radiation and Nuclear Safety and Security (Official Gazette of RS, No. 95/2018 and 10/2019), along with a series of Rulebooks, including the Rulebook for Establishing Programme of Systematic Environmental Radioactivity Examination (Official Gazette of RS, No. 100/2010), and Rulebook on Radioactivity Monitoring (Official Gazette of RS, No. 97/2011). In accordance with these regulations, in Serbia regular and systematic sampling of various environmental matrices, including air, precipitation, soil, vegetation, foodstuffs, drinking water, surface waters are conducts. Surface water monitoring plays a critical role in Serbia’s radiological surveillance system due to the country’s geographical position downstream from two operational nuclear power plants: Nuclear Power Plant Krško in Slovenia, and Nuclear Power Plant Paks in Hungary. In the event of a radiological incident, these upstream facilities could impact major rivers flowing through Serbia, primarily the Sava and the Danube River Basin. The radioactivity monitoring program focuses on measuring the concentrations of naturally occurred radionuclides as well as artificial such as Cs-137, Sr-90, and tritium. Additionally, following the signing of the Agreement between the Government of the Republic of Serbia and the Government of Hungary on Cooperation in the Field of Sustainable Management of Transboundary Waters and River Basins of Common Interest, radioactivity monitoring has been established in the Danube River at the transboundary section with Hungary, specifically at monitoring stations located in Bezdan (Serbia) and Mohács (Hungary). This monitoring represents a key component of transboundary water quality control and plays an important role in the early detection of potential radiological impacts originating upstream, including those associated with the operation of nuclear power plants such as Paks in Hungary. Monitoring radioactivity in surface waters is of critical importance for environmental protection and public health, particularly in terms of detecting artificial radionuclides. Nuclear power plants, which are primarily located on major rivers, present potential sources of radioactive contamination, especially in the event of accidents or contamination during cooling processes. Artificial radionuclides such as Cs-137 and Sr-90, can have long-term ecological and health impacts. Therefore, early detection of these radionuclides in aquatic ecosystems is essential. Given that rivers serve as the primary watercourses for the cooling systems of nuclear plants, there is a real risk of these pollutants being transferred into broader ecological systems. An effective surface water monitoring system, which includes analyses for artificial radionuclides, enables timely detection and the implementation of preventive measures to mitigate the risk of long-term environmental and health consequences.International conference on radiation applications in Physics, Chemistry, Biology, Medical Sciences, Engineering and Environmental Sciences : May 26-30, Crete, Greece