Multiple gigantic renal cysts

Introduction. Cystic renal lesions are very heterogeneous lesions which differ in ethiopathogenesis, morphological and clinical manifestations, and also in evolution and therapy. Classification of cystic lesions is complex, symptomatology is poor, and diagnosis is based on complete radiological diagnostic procedures. Case report. We presented a 20-year old patient with mild subjective symptoms. Objectively, he was without positive clinical signs and changes in biochemistry of blood. Using ultrasonography (US) multiple serous simple cysts were found in both kidneys. Using computed tomography (CT) multiple serous cysts were found, without changes in cystic walls, with preserved renal parenchyma and without cystic changes on other parenchymatous organs. Conclusion. Although renal cystic lesions are frequent in adult population, this is a rare example of a young adult man with simple, gigantic, serous cysts which do not produce clinical manifestations nor functional renal difficulty so far

The Bray-Liebhafsky oscillatory reaction: Kinetic investigations in reduction and oxidation pathways based on hydrogen peroxide concentration monitoring

By direct monitoring of the hydrogen concentration during its catalytic decomposition into water and oxygen in the presence of potassium iodate and sulfuric acid, that is in the Bray-Liebhafsky system, the pseudo-rate constants of overall reduction and oxidation pathways were determined The dependence of the obtained rate constants on acidity was evaluated. It was found that the pseudo-rate constant of the overall reduction process increases with increasing acidity, whereas the pseudo-rate constant of the overall oxidation process decreases with increasing acidity. The corresponding activation energies were also calculated using values of this constant at two temperatures.Direktnim praćenjem koncentracije vodonik-peroksida u toku njegovog katalitičkog razlaganja na vodu i kiseonik u prisustvu kalijum-jodata i sumporne kiseline, odnosno u Bray-Lievhafsky sistemu, analizirane su konstante brzina celokupnog redukcionog i oksidacionog puta kao konstante brzina pseudo-prvog reda. izvedene su njihove zavisnosti od kiselosti. Nađeno je da pseudo-konstanta brzine celokupnog redukcionog procesa raste sa porastom kiselosti, dok pseudo-konstanta brzine celokupnog oksidacionog procesa opada sa porastom kiselosti. korišćenjem njihovih vrednosti na dve temperature izračunate su odgovarajuće energije aktivacija

Alterations of Sleep and Sleep Oscillations in the Hemiparkinsonian Rat.

Our previous studies in the rat model of Parkinson's disease (PD) cholinopathy demonstrated the sleep-related alterations in electroencephalographic (EEG) oscillations at the cortical and hippocampal levels, cortical drives, and sleep spindles (SSs) as the earliest functional biomarkers preceding hypokinesia. Our aim in this study was to follow the impact of a unilateral substantia nigra pars compacta (SNpc) lesion in rat on the cortical and hippocampal sleep architectures and their EEG microstructures, as well as the cortico-hippocampal synchronizations of EEG oscillations, and the SS and high voltage sleep spindle (HVS) dynamics during NREM and REM sleep. We performed unilateral SNpc lesions using two different concentrations/volumes of 6-hydroxydopamine (6-OHDA; 12 μg/1 μl or 12 μg/2 μl). Whereas the unilateral dopaminergic neuronal loss >50% throughout the overall SNpc rostro-caudal dimension prolonged the Wake state, with no change in the NREM or REM duration, there was a long-lasting theta amplitude augmentation across all sleep states in the motor cortex (MCx), but also in the CA1 hippocampus (Hipp) during both Wake and REM sleep. We demonstrate that SS are the hallmarks of NREM sleep, but that they also occur during REM sleep in the MCx and Hipp of the control rats. Whereas SS are always longer in REM vs. NREM sleep in both structures, they are consistently slower in the Hipp. The dopaminergic neuronal loss increased the density of SS in both structures and shortened them in the MCx during NREM sleep, without changing the intrinsic frequency. Conversely, HVS are the hallmarks of REM sleep in the control rats, slower in the Hipp vs. MCx, and the dopaminergic neuronal loss increased their density in the MCx, but shortened them more consistently in the Hipp during REM sleep. In addition, there was an altered synchronization of the EEG oscillations between the MCx and Hipp in different sleep states, particularly the theta and sigma coherences during REM sleep. We provide novel evidence for the importance of the SNpc dopaminergic innervation in sleep regulation, theta rhythm generation, and SS/HVS dynamics control. We suggest the importance of the underlying REM sleep regulatory substrate to HVS generation and duration and to the cortico-hippocampal synchronizations of EEG oscillations in hemiparkinsonian rats

The Bray-Liebhafsky oscillatory reaction: Kinetic investigations in reduction and oxidation pathways based on hydrogen peroxide concentration monitoring

By direct monitoring of the hydrogen concentration during its catalytic decomposition into water and oxygen in the presence of potassium iodate and sulfuric acid, that is in the Bray-Liebhafsky system, the pseudo-rate constants of overall reduction and oxidation pathways were determined The dependence of the obtained rate constants on acidity was evaluated. It was found that the pseudo-rate constant of the overall reduction process increases with increasing acidity, whereas the pseudo-rate constant of the overall oxidation process decreases with increasing acidity. The corresponding activation energies were also calculated using values of this constant at two temperatures.Direktnim praćenjem koncentracije vodonik-peroksida u toku njegovog katalitičkog razlaganja na vodu i kiseonik u prisustvu kalijum-jodata i sumporne kiseline, odnosno u Bray-Lievhafsky sistemu, analizirane su konstante brzina celokupnog redukcionog i oksidacionog puta kao konstante brzina pseudo-prvog reda. izvedene su njihove zavisnosti od kiselosti. Nađeno je da pseudo-konstanta brzine celokupnog redukcionog procesa raste sa porastom kiselosti, dok pseudo-konstanta brzine celokupnog oksidacionog procesa opada sa porastom kiselosti. korišćenjem njihovih vrednosti na dve temperature izračunate su odgovarajuće energije aktivacija

Comparative evaluation of antimutagenic and antimitotic effects of Morchella esculenta extracts and protocatechuic acid

Morchella esculenta (L.) Pers. methanolic extracts, obtained from fruiting bodies growing wild in Serbia and Portugal, were screened for their antimutagenic properties and compared to protocatechuic acid, previously identified in both species. Salmonella typhimurium TA100 reversion assay was used for the antimutagenic properties. Methanolic extracts expressed important antimutagenic potency towards S. typhimurium, which was documented by index of antimutagenicity (I). Sample from Serbia expressed slightly higher antimutagenic properties with inhibition rate of 58.7%. Sample from Portugal gave inhibition rate of 51.7%. Protocatechuic acid had inhibition rate I of his+ revertants of 72.4%. Cell viability in the presence of extracts was also documented. M. esculenta samples from Serbia and Portugal possessed novel biological potential for the studied species, as well as its phenolic compound – protocatechuic acid, identified in both samples. Genotoxic effect, regarding mitotic index and chromosomal aberration score, was also assessed by using Allium cepa L. assay. Protocatechuic acid showed the most significant decrease in mitotic index, as well as decrease in chromosomal aberration score.Serbian Ministry of Education, Science and Technological Development; FCT Portugal; COMPETE/QREN/EU, PTDC/AGR-ALI/110062/2009 PEst-OE/AGR/UI0690/201

Propeller and combinatory characteristics determination of Kaplan turbine in HPS 'Zvornik' with the aim of increasing its efficiency

U radu su prikazani rezultati merenja i proračuna koji su urađeni na agregatu A3 u HE 'Zvornik', a u cilju određivanja propelernih i kombinatorskih karakteristika Kaplanove turbine. Specifična pažnja je posvećena određivanju koeficijenta protoka protokomera Vinter-Kenedi. Ova merenja daju rezultate koji omogućuju rad turbine u tačkama optimalnih stepena korisnosti. .The measurement and calculation results which were performed at unit A3 in HPS 'Zvornik' are presented in this paper with the aim of Kaplan turbine propeller and combinatory characteristics determination. Special attention is given to the Winter-Kennedy discharge coefficient determination. These measurement procedures gave the opportunity for unit operation at optimal efficiencies.

Chemical composition of the mushroom Meripilus giganteus Karst. and bioactive properties of its methanolic extract

Wild Meripilus giganteus Karst belongs to the order Polyporales, in which some members are known to possess a wide range of pharmacological properties. M. giganteus showed to be rich in carbohydrates (74.49 g/100 g) and proteins (15.94 g/100 g), presenting low fat content (1.51 g/100 g). Chemical composition was determined by using chromatographic techniques. Also, various bioactive compounds were detected including all four tocopherol isoforms with d- and ?-tocopherols being predominant (123.35 and 77.80 µg/100 g, respectively); five organic acids (oxalic, malic, quinic, citric and fumaric acids) with predominant malic acid (3.17 g/100 g); and three phenolic acids and related compounds (p-hydroxybenzoic, p-coumaric and cinnamic acids; 1010, 2420 and 340 µg/100 g, respectively). M. giganteus methanolic extract exhibited antioxidant activity tested by five different assays with the strongest potential in TBARS assay (EC 50 0.31 mg/mL); and antimicrobial activities (MIC/MBC 0.0125–5 mg/mL; MIC/MFC 0.025–0.4 mg/mL). Furthermore, treatment of cervical carcinoma cell line (HeLa) led to reduction in cell's viability in MTT assay (IC 50 0.41 mg/mL after 48 h), induced process of apoptosis and inhibited cell's migration in vitro. The analysed extract was not toxic for zebrafish embryos (at 0.5 mg/mL), indicating its biosafety and potential application as a dietary supplement in chemoprevention.This work was supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia (grant numbers 173032, 173051 and 47025). Authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support to CIMO (Pest-OE/AGR/UI0690/2015) and L. Barros grant (SFRH/BPD/107855/2015). We would like to thank dr Jelena Dinic for help in performing DAPI/PI staining.info:eu-repo/semantics/publishedVersio

Razvoj i validacija nove analitičke metode za pripremu uzoraka vode za kvantifikaciju policikličnih aromatičnih ugljovodonika primenom gasne hromatografije - masene spektrometrije

Polycyclic aromatic hydrocarbons (PAHs) are organic compounds whose structure consists of two or more condensed aromatic rings. Due to their toxicity and persistence in the environment, PAHs monitoring is very important especially in water, from where they can through the food chain or directly reach humans. In this doctoral dissertation, a method for the determination of PAHs in water, using gas chromatography - mass spectrometry method was optimized and validated. In the sample preparation technique, dispersive micro-solid phase extraction, new sorbents, prepared by thermal and chemicalthermal modification of natural zeolite, clinoptilolite, were used. After optimization and validation experiments, it was concluded that applying 200 mg of acid-thermal modification (prepared modifying clinoptilolite using 1.5 mol L-1 hydrochloric acid and thermally treated at temperature of 500 oC) enabled achieving the best analytical characteristics. Efficiency values ranged from 69% (dibenzo[a,h]anthracene) to 123% (pyrene). The obtained analytical parameters of the method validation were within the validation criterias. The optimized and validated method was used for analysis of real water samples of the river Nišava and its tributaries in the territory of municipalities Dimitrovgrad, Pirot, Bela Palanka and Niš. Naphthalene, acenaphthylene, acenaphthene and fluorene were present in all samples, and the total concentration of PAHs varied depending on the sampling site, and was in the interval of 6.47 - 33.6 μg L-1, where tributaries contributed to the increase of the total PAHs concentration in Nišava. The obtained individual and total concentrations were higher than the limits prescribed by official regulations and it was concluded that the river Nišava in the territory of Serbia has been contaminated with PAHs, of which light PAHs were predominantly presented in all samples

EKSPERIMENTALNA KARAKTERIZACIJA FOTOAKUSTIČKOG MERNOG SISTEMA

The photoacoustic effect, as a non-destructive method, has increased application in defining thermal and optical properties of materials. Since the measurement of photoacoustic signal requires use of an electronic system, knowledge of the transfer function of the measurement system is a prerequisite for its application. This paper presents two different experimental techniques for the determination of the transfer function of a PA measurement system.Fotoakustički (FA) efekat kao nedestruktivna metoda ima sve veću primenu u određivanju termičkih i optičkih osobina materijala. S obzirom da merenje fotoakustičkog signala zahteva upotrebu elektronskog sistema, poznavanje prenosne funkcije mernog sistema postaje preduslov za  njegovu primenu. Ovaj rad predstavlja dve različite eksperimentlane tehnike za određivanje prenosne funkcije FA mernog sistema

The influence of human factor on student satisfaction in higher education institutions

Due to constantly increasing competition in the higher education market, customer or user satisfaction should be made the focal point of all higher education institutions. Creating happier, satisfied customers, whether they are students, their parents, donors, professors or employers, should be the primary objective which will also contribute to the quality of the educational institutions. In line with that, this paper aims to show the extent to which human factor (as a tool of marketing mix) and all elements associated with it, affect student satisfaction in higher education institutions. The survey was conducted on a sample of 703 respondents, i.e. students of four faculties which are part of the University Business Academy in Novi Sad. A questionnaire created specially for research purposes was used as an instrument for data collection. The analysis of collected data included correlation and regression analysis. The obtained results indicate a statistically significant correlation between the human factor and the satisfaction of students in higher education institutions. The paper touches upon the impact of each element on the satisfaction of students. Such analysis provides us with important indicators in terms of specific elements of human factor which should be improved if we want to improve the overall satisfaction of students in higher education institutions. Finally, the paper outlines possible conclusions and recommendations for further research on the basis of the obtained results