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Publikacije (45086)

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Z. Pilić, Herzegovina

The effect of the aqueous extract of Achillea millefolium L . (AM) on the electrochemical behaviour of iron in a simulated acid rain solution (pH 4.5) was studied by electrochemical techniques cyclic voltammetry, potentiodynamic polarization and electrochemical impedance spectroscopy. Experiments were carried out over a wide range of AM concentrations. The results of all techniques showed that AM extract contributes to iron passivation. The films formed in the presence of AM extract were thinner and more resistive then the films formed in pure simulated acid rain solution. The AM extract adsorbed on the iron according to the Freundlich isotherm. The thermodynamic data indicated physical adsorption of the AM extracts on the iron surface. The concentration of the metallic ions released into solution, measured by atomic absorption spectroscopy, was in accordance with the results obtained from the electrochemical techniques.

Background: The gene for 5,10-methylenetetrahydrofolate reductase (NAD(P)H) or MTHFR gene encodes protein methylenetetrahydrofolate reductase (MTHFR), an enzyme important in folate metabolism. Aim: The aim of this study was to determine the frequencies of 677C>T and 1298A>C polymorphisms in the MTHFR gene of healthy subjects from the population. Material and methods: The blood samples were collected from 164 unrelated and healthy donors from population consisted of 98 females and 66 males. Both the MTHFR 677C>T and 1298A>C single nucleotide polymorphisms (SNPs) were analyzed by Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Linkage disequilibrium (LD) between pair of SNPs was calculated through Haploview analysis. Results: The frequency of MTHFR 677T allele in the population (32.62%) was in agreement with the frequency of this allele in most other populations, however, the frequency of MTHFR 1298C allele (38.41%) was higher than that reported for most other populations in the world. Haploview analysis showed a relatively strong LD between 677C>T and 1298A>C SNPs with D′ values of 0.87. Conclusion: Regarding the two MTHFR polymorphisms, three of the nine combined genotypes were present in 87.2% of the population. 33.54% subjects were complex heterozygous (677CT/1298AC genotype), 34.15% subjects had 677CC/1298AC and 19.51% of 677CT/1298AA genotype. The subjects with 677TT genotype had a 1298AA or 1298AC genotype while subjects with 1298CC genotype had only 677CC genotype. The subjects with 677CC/1298AA genotype were only 3.05%. We were not found triple 677CT/1298CC and quadruple 677TT/1298CC mutation suggesting decreased viability of embryos with increased numbers of mutant alleles.

UDK 581.19:547.56]:582.736.3 The aim of this study was to determine the total concentrations of some phenolic compounds and antioxidant and antimicrobial activity of methanol extracts of different parts of Illyrian endemic Petteria ramentacea. Concentrations of phenolic compounds were determined with UV/VIS spectrophotometry. The antioxidant activity of plant extracts was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. Antimicrobial activity of extracts was evaluated by measuring the inhibition's zone against six selected test bacteria and two fungi. The highest average total phenols concentrations were in seeds (10.78 mg GAE g-1 DW), root (10.51 mg GAE g-1 DW) and bark (10.40 mg GAE g-1 DW), and the lowest in inflorescences (2.99 mg GAE g-1 DW) and leaves (3.12 mg GAE g g-1 DW). The total flavonoids concentrations were determined only in leaves (8.25 mg CE g-1 DW) and in stem (5.66 mg CE g-1 DW). Both flavanols and proanthocyanidins (0.75 mg CE g-1 DW and 3.49 mg CE g-1 DW, respectively) were found only in leaves. Analysis of variance indicated presence of significant differences between total phenols and flavanols concentrations (p<0.05), and Duncan's test confirmed the presence of intraspecies variability according to their concentrations. The highest antioxidant activity (IC50) was observed for the seed's extract (6.86%) and the lowest for the bark’s (51.31%). All methanol extracts showed the most pronounced antibacterial activity against Staphylococcus epidermididis, and the lowest against S. aureus subsp. aureus. Antifungal activity against Candida albicans was moderate. Since Peteria ramentacea methanol extracts are potential natural antioxidant and antimicrobial preparations against selected microorganisms, it is necessary to continue with more detailed analysis.

Denis Jurečić, Vilko Žiljak, M. Kudumovic, Božica Kelčec Pester, Herzegovina

In the article is presented the design for security graphics on packaging with invisible information. The color choice is underlined by the INFRAREDESIGN® theory. Individual solutions for joining two independent images are realized with digital printing and interpreted with computer animation. Separation of the dye is performed for the default response of the hidden drawing that is released by the infrared camera. Product recognition is with IRD process as a "visual information identity". Hidden graphics are designed with a protective line solution. Experiments have been carried out in the pharmaceutical field, on the packaging of drugs. Proving the authenticity of the content is carried out by recording the packaging and comparing it with the specimen that was recorded as photographs of the twenty light blockades in the visual and infrared spectrum.

D. Nakić, D. Vouk, N. Štirmer, M. Serdar

An increasing trend of sludge generation at wastewater treatment plants (WWTP) has been observed in developing countries like Croatia. Thermal processing of sewage sludge facilitates its further management, although ash is generated as new waste in the process. The proposed approach, while eliminating the need to dispose ash at non-hazardous waste disposal sites, directly reduces not only the sludge and ash disposal costs, but also the raw cement production costs. All analysed technical and environmental requirements are met when 20 % of cement is replaced with ash.

Jackie Mullins, Mirza Pojskić, F. Boop, K. Arnautović

OBJECTIVE Outpatient anterior cervical discectomy and fusion (ACDF) is becoming more common and has been reported to offer advantages over inpatient procedures, including reducing nosocomial infections and costs, as well as improving patient satisfaction. The goal of this retrospective study was to evaluate and compare outcome parameters, complication rates, and costs between inpatient and outpatient ACDF cases performed by 1 surgeon at a single institution. METHODS In a retrospective study, the records of all patients who had undergone first-time ACDF performed by a single surgeon in the period from June 1, 2003, to January 31, 2016, were reviewed. Patients were categorized into 2 groups: those who had undergone ACDF as outpatients in a same-day surgical center and those who had undergone surgery in the hospital with a minimum 1-night stay. Outcomes for all patients were evaluated with respect to the following parameters: age, sex, length of stay, preoperative and postoperative pain (self-reported questionnaires), number of levels fused, fusion, and complications, as well as the presence of risk factors, such as an increased body mass index, smoking, and diabetes mellitus. RESULTS In total, 1123 patients were operated on, 485 (43%) men and 638 (57%) women, whose mean age was 50 years. The mean follow-up time was 25 months. Overall, 40.5% underwent 1-level surgery, 34.3% 2-level, 21.9% 3-level, and 3.2% 4-level. Only 5 patients had nonunion of vertebrae; thus, the fusion rate was 99.6%. Complications occurred in 40 patients (3.6%), with 9 having significant complications (0.8%). Five hundred sixty patients (49.9%) had same-day surgery, and 563 patients (50.1%) stayed overnight in the hospital. The inpatients were older, were more commonly male, and had a higher rate of diabetes. Smoking status did not influence the length of stay. Both groups had a statistically significant reduction in pain (expressed as a visual analog scale score) postoperatively with no significant difference between the groups. One- and 2-level surgeries were done significantly more often in the outpatient setting (p < 0.001). The complication rate was 4.1% in the outpatient group and 3.0% in the inpatient group; there was no statistically significant difference between the 2 groups (p = 0.339). Significantly more complications occurred with 3- and 4-level surgeries than with 1- and 2-level procedures (p < 0.001, chi-square test). The overall average inpatient cost for commercial insurance carriers was 26% higher than those for outpatient surgery. CONCLUSIONS Anterior cervical discectomy and fusion is safe for patients undergoing 1- or 2-level surgery, with a very significant rate of pain reduction and fusion and a low complication rate in both clinical settings. Outpatient and inpatient groups undergoing 3- or 4-level surgery had an increased risk of complications (compared with those undergoing 1- or 2-level surgery), with a negligible difference between the 2 groups. This finding suggests that these procedures can also be included as standard outpatient surgery. Comparable outcome parameters and the same complication rates between inpatient and outpatient groups support both operative environments.

I. Brizić, Božo Šušak, Maja Arapović, P. Huszthy, L. Hiršl, Daria Kveštak, Vanda Juranić Lisnić, M. Golemac et al.

J. Irving, S. Cottaar, V. Lekić

Seismic properties and equation-of-state parameters of the liquid iron alloy in the outer core are inferred from normal mode data. Turbulent convection of the liquid iron alloy outer core generates Earth’s magnetic field and supplies heat to the mantle. The exact composition of the iron alloy is fundamentally linked to the processes powering the convection and can be constrained by its seismic properties. Discrepancies between seismic models determined using body waves and normal modes show that these properties are not yet fully agreed upon. In addition, technical challenges in experimentally measuring the equation-of-state (EoS) parameters of liquid iron alloys at high pressures and temperatures further complicate compositional inferences. We directly infer EoS parameters describing Earth’s outer core from normal mode center frequency observations and present the resulting Elastic Parameters of the Outer Core (EPOC) seismic model. Unlike alternative seismic models, ours requires only three parameters and guarantees physically realistic behavior with increasing pressure for a well-mixed homogeneous material along an isentrope, consistent with the outer core’s condition. We show that EPOC predicts available normal mode frequencies better than the Preliminary Reference Earth Model (PREM) while also being more consistent with body wave–derived models, eliminating a long-standing discrepancy. The velocity at the top of the outer core is lower, and increases with depth more steeply, in EPOC than in PREM, while the density in EPOC is higher than that in PREM across the outer core. The steeper profiles and higher density imply that the outer core comprises a lighter but more compressible alloy than that inferred for PREM. Furthermore, EPOC’s steeper velocity gradient explains differential SmKS body wave travel times better than previous one-dimensional global models, without requiring an anomalously slow ~90- to 450-km-thick layer at the top of the outer core.

Adela Delalić, M. Čurković, J. Antic

Abstract The paper provides an overview of the trend in the concentration of the total assets of banks in Croatia for the period from 2007 to 2016 with the aim of analysing and presenting the changes that occurred in the system. Also, the paper shows the theoretical framework of the indicators used in the research as well as the comparison of their obtained values. The data used to calculate the total assets concentration are taken from the Croatian National Bank. The concentration indices used in the study include the entropy measure, the Theil entropy, the Gini coefficient, the Pietra index, the Atkinson index and the coefficient of variation. The results indicate a very slight decrease in concentration over the past several years, while the coefficient of variation points to the heterogeneity of the system, as well as to inequalities among the banks, which are most evident in the size of banks assets.

Slavica Terzić, D. Lazarević, B. Nedić, Ž. Šarkočević, Jasmina Dedić

Even though coordinate measuring machines (CMM) still achieve the most accurate measurement results, non-contact (optical) measuring systems are applied more and more in industry. The reasons of using optical scanners are in the higher speed of acquisition, higher density of data-points and better surface description, the ability to scan complex and non-rigid surfaces etc in comparison to contcact devices. This paper gives a review of state-of-the-art measuring contact and non-contact inspection technologies in industrial applications. Listed are the devices, principles and systems that are used at the data-acquisition (triangulation, time-of-flight and interferometry). The description of contact measuring machines (portable CMM and stationary CMM) and devices for non-contact scanning (laser scanner, structured light scanner and CT scanner) is given, and their advatages and disadvantages are mentioned with corresponding literature review.

M. Pavlović, S. Arandelovic, N. Ljubijankić, S. Grgurić‐Šipka, S. Radulović

Introduction Since the discovery and clinical success of the platinum(II) anticancer drug, cisplatin, researchers are putting much effort to develop more efficient metal-based therapeutic compounds, with fewer side-effects and greater cytoselectivity. Ruthenium complexes arose as promising anticancer agents, due to the success of some ruthenium drug candidates in clinical trials. Here we report comparison of in vitro cytotoxic activity and mechanisms of action of cisplatin and four newly synthesised ruthenium(III) complexes with bidentate anionic schiff base derived from 5-methylsalicilaldehyde and methylamine: (complexes 1– 4). Material and methods Cytotoxicity was tested on four human cancer cell lines (K562, A549, EA.hy926, MDA-MB231) and one human non-tumour cell line (MRC-5), by MTT assay. Being the most cytotoxic of all four tested complexes, complex 1 (C1) (Na[RuLCl2], L=N-propyl-5-chlorosalicideniminato) is selected for further analyses of molecular mechanisms underlying its activity toward MDA-MB231 cells. Results and discussions The average IC50 values were in the low micromolar range 2–23 µM, depending on cell line. Investigated complexes displayed an apparent cytoselective profile, as they reduced the viability of tested tumour cell lines more efficiently than of the non-tumour MRC-5 cells. Cisplatin resistant MDA-MB231 cells showed to be ten times more sensitive to C1 (IC50=2 µM) than to cisplatin. 24 hour treatment of MDA-MB231 cells with IC50 values of C1 and cisplatin induced minor cell cycle alterations, while 48 hour treatment induced substantial accumulation of cells in Sub-G1 region, up to 22.4% (C1) and 86.4% (cisplatin), versus control 4.8%. Acridine orange/ethidium bromide dual staining confirmed the Annexin V-FITC/PI assay results of notable reduction in cell number after the treatment with C1 and cisplatin. While cisplatin-treated cells prominently die of necrosis, C1-treated cells after 24 hour treatment show apoptotic morphology, but after prolonged treatment, necrosis becomes predominant. Decrease in the intracellular levels of reactive oxygen species was comparable in the cisplatin-treated and C1-treated cells, with cisplatin displaying more conspicuous effects at higher dose. C1 entered the cells more efficiently compared to cisplatin. Intracellular C1 concentration after 4 hour treatment exceeded that of cisplatin by 7.8 times approximately. Conclusion Present study pointed out interesting activity of this type of ruthenium(III) complex and need for further biological studies and its chemical structure optimisation.

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