Comparison between Carotid Artery Wall Thickness Measured by Multidetector Row Computed Tomography Angiography and Intimae-Media Thickness Measured by Sonography

The increased thickness of the carotid wall >1 mm is a significant predictor of coronary and cerebrovascular diseases. The purpose of our study was to assess the agreement between multidetector row computed tomography angiography (MDCTA) in measuring carotid artery wall thickness (CAWT) and color Doppler ultrasound (CD-US) in measuring intimae-media thickness (IMT). Eighty-nine patients (aged 35–81) were prospectively analyzed using a 64-detector MDCTA and a CD-US scanner. Continuous data were described as the mean value ± standard deviation, and were compared using the Mann–Whitney U test. A p value <0.05 was considered significant. Bland–Altman statistics were employed to measure the agreement between MDCTA and CD-US. CAWT ranged from 0.62 to 1.60 mm, with a mean value of 1.09 mm. IMT ranged from 0.60 to 1.55 mm, with a mean value of 1.06 mm. We observed an excellent agreement between CD-US and MDCTA in the evaluation of the common carotid artery thickness, with a bias between methods of 0.029 mm (which is a highly statistically important difference of absolute values [t = 43.289; p < 0.01] obtained by paired T test), and limits of agreement from 0.04 to 0.104. Pearson correlation coefficient was 0.9997 (95% CI 0.9996–0.9998; p < 0.01). We conclude that there is an excellent correlation between CAWT and IMT measurements obtained with the MDCTA and CD-US

Позитрон - 22

Хемијски факултет је први пут ове године учествовао у Global Women’s Breakfast, прочитајте како нам је било. Омиљене асистенткиње нашег Факултета су са нама поделиле чиме се научно занимају (рубрика: Укратко о подугачком) и шта их инспирише у раду са студнетима. Наша дописница се потрудила да објасни главне састојке чоколаде. О хемикалијама којима комуницирају разне врсте, прочитајте у тексту Семиохемикалије. Уколико често одлажете своје обавезе, похитајте да прочитате текст о прокрастинацији. Згодан текст за учење Аналитичке хемије 1, али и разумевање пиротехнике, управо је текст који се бави хемијом ватромета. Наша професорка се потрудила да нам пренесе најважнија сазнања о вакцинама. Летњи семестар и лепо време су период када је потребно више мотивације да останемо унутра и учимо – зато преносимо речи светских научника, Снежане Ђорђевић и Далибора Станковића. Забавите се уз Хемијске мозгалице и Позитиву. Подсетите најважнијих догађаја у свету хемичара уз Ретросинтезу

Biocompatible microemulsions for improved dermal delivery of sertaconazole nitrate: Phase behavior study and microstructure influence on drug biopharamaceutical properties

The aim of this study was development of biocompatible topical microemulsions (MEs) for incorporation and improved dermal delivery of sertaconazole nitrate (SN). For this purpose, phase behavior and microstructure of pseudo-ternary glycereth-7-caprylate/caprate (Emanon EV-E, EV)/cosurfactant/Capryol (TM) 90/water systems were investigated. Furhermore, the influence of these properties on the drug skin delivery was also assessed. Expansion of ME single-phase regions with the use of short chain alcohols was a consequence of the more fluid interface when compared to other investigated systems, which was confirmed by electron paramagnetic resonance spectroscopy-EPR. The chosen bicontinuous to inverted bicontinuous formulations were assessed against the ME based on polysorbate 80 as referent sample. Despite incorporation of SN within the selected formulations induced similar alternations in electrical conductivity, viscosity and pH values, obtained EPR spectra suggested different SN localization: within the oil phase (for most of the EV based formulations), or interacting with the interface (polysorbate 80 based formulation). Due to higher in vitro drug release (12.24%-18.53%), ex vivo SN penetration into porcine ear skin (dermal retention Enhancement Ratio (ERO) ranged from 2.66 to 4.25) and pronounced antifungal activity, the chosen MEs represent promising vehicles for dermal delivery of SN in treatment of cutaneous fungal infections. The biopharmaceutical and skin performance differences obtained with different formulations were possible to be explained on the basis of their physicochemical characteristics.This is the peer-reviewed version of the article: Pajic, N. B., Nikolić, I., Mitsou, E., Papadimitriou, V., Xenakis, A., Randjelović, D., Dobricic, V., Smitran, A., Cekic, N., Calija, B.,& Savić, S. D. (2018). Biocompatible microemulsions for improved dermal delivery of sertaconazole nitrate: Phase behavior study and microstructure influence on drug biopharamaceutical properties. Journal of Molecular LiquidsElsevier Science Bv, Amsterdam., 272, 746-758. [https://doi.org/10.1016/j.molliq.2018.10.002]The published version: [https://cer.ihtm.bg.ac.rs/handle/123456789/2360

ПОРЕЂЕЊЕ ELISA И HPLC МЕТОДЕ ЗА ДЕТЕКЦИЈУ МИКОТОКСИНА АНАЛИЗОМ РЕЗУЛТАТА PROFICIENCY ТЕСТОВА

Different analytical techniques for the detection of mycotoxins have been developed in order to control the levels of mycotoxins in food and feed. Conventional analytical methods for mycotoxin determination are involving techniques such as thinlayer chromatography (TLC), high-performance liquid chromatography (HPLC) and gas chromatography (GC). Also, rapid methods for mycotoxin analysis have become increasingly important. Enzyme-linked immuno-sorbent assay (ELISA) is one of the most common rapid methods for determination of these natural contaminants. The aim of this study was to provide a comparison between two different methods of analysis (HPLC and ELISA) for the detection of different mycotoxins using data that originate from commercial proficiency tests. Based on the statistical evaluation of the results for both methods, in three proficiency tests for various mycotoxins (aflatoxins, ochratoxin and zearalenone), it could be concluded that both techniques can equally be used, although ELISA is considered to be the screening one.У циљу контроле присуства микотоксина и нивоа контаминације хране и хране за животиње развијене су различите аналитичке технике за детекцију ових природних контаминената. Конвенционалне аналитичке методе за утврђивање микотоксина су танкослојна хроматографија (ТЛЦ), течна хроматографија високих перформанси (ХПЛЦ) и гасна хроматографија (ГЦ). Такође, брзе методе за микотоксиколошке анализе постају све важније, међу којима је ЕЛИСА (Enzyme linked immuno-sorbent assay) једна од најприменљивијих. Циљ овог рада био је да се две различите и најчешће коришћене лабораторијске методе за утврђивање различитих микотоксина (ХПЛЦ и ЕЛИСА) упореде анализом података који потичу из комерцијалних тестова оспособљености (proficiency тестова). На основу детаљне статистичке процене резултата добијених применом ових метода за квантификацију афлатоксина, охратоксина и зеараленона, у три комерцијална proficiency теста, може се закључити да обе технике могу равноправно да се користе с великом поузданошћу, иако се често наводи да је ЕЛИСА погодна само за почетну тријажу узорака

Variability of agronomic traits in vegetable pea (Pisum sativum L.) genotypes

In this study, a total of 12 vegetable pea genotypes of different growing seasons were subjected to phenotypic characterization. The vegetable pea genotypes are a part of the collection maintained at the Institute of Field and Vegetable Crops Novi Sad. The plant material included 10 promising lines and two released cultivars, Tamiš and Dunav. The trial was carried out in 2022. It was set up at the Rimski Šančevi site, as a randomized block design in five replications. A total of 14 agronomic traits were analyzed. The obtained research results revealed divergence in the investigated plant material. The statistical significance of all sources of variation was determined by the LSD test. The height of the first fertile node was found to be the most variable feature, with a coefficient of variation of 40.54%. The tested genotypes were clustered into two groups and two subgroups within the second group. The correlation analysis of the examined quantitative traits revealed the presence of several statistically significant positive and negative correlations. Some of the most significant positive correlations were established between the grain weight per plant and the number of grains per plant and the yield of technologically mature grain, while the pod width and the number of fertile nodes per plant had the most negative correlations with the other tested traits

Optimizacija mlevenja aktivne komponente i hidrofobizacija dobijenog sredstva za gašenje požara]

This work presents a grinding process of monoammonium phosphate (MAP) as an active component in a powder fire extinguisher (PFE). The aim was to determine the grinding time for reaching the optimal particle size of MAP necessary for permanent fire extinguishing. MAP grinding was performed by using a laboratory ceramic ball mill and a vibrating cup mill. The grinding process was controlled by sieving using a 100 µm sieve at precisely defined time intervals. The efficiency of a PFE depends on the share of the -100 µm fraction of the active component, which has to exceed 60 %. The optimal grain size with 64 % of fraction of particle size -100 µm was obtained after 33 min of grinding of ≈3000 µm mm grain size MAP by using a ball mill (single-stage grinding). In two-stage process, by grinding the same initial MAP sample (≈3000 µm) in the vibro mill for 10 min, powder with the upper limit grain size of 300 µm and the mean grain diameter of 120 µm was obtained. This sample with a reduced size was further ground in the ceramic ball mill yielding 67.5 % of the fraction of particle size -100 µm after 19 min. The total time of the two-stage grinding process was 29 min. By analyzing the grinding time of MAP required to get the lowest required share of the fraction of particle size -100 µm that provides the effectiveness of formed PFE it can be concluded that 64 % of this fraction was obtained after 33 min of single-stage grinding, while only after 26 min in the two-stage process. Thus, the grinding time was reduced by 7 min indicating certain energy savings. Stability and hydrophobicity of the obtained PFE were achieved by coating with magnesium stearate (MgSt) at the content of 2 % in a ball mill for 15 min. The coating was confirmed by the standardized procedure for verification of PFE hydrophobic properties in contact with water drops. To obtained PFE had component mass ratios of MAP:AS:CC:QS:MgSt=55:20:18:5:2 (AS-ammonium sulfate; CC-calcium carbonate, QS-quartz sand) and was further characterized by chemical and granulometric analyses. The fire extinguishing efficiency of the PFE was tested in controlled conditions, whereby fires were initiated by burning solid materials and flammable liquids. In both cases, immediate elimination of flames was achieved, thus proving the efficiency of the PFE obtained in this work for practical applications.U radu je prikazan postupak mlevenja monoamonijum fosfata (MAP) kao aktivne komponente u praškastom sredstvu za gašenje požara (SGP). Cilj je bio da se utvrdi vreme mlevenja MAP koje je potrebno za dobijanje optimalne granulacije za potpuno gašenje požara i eliminisanje plamena. MAP je mleven u laboratorijskom keramičkom mlinu sa kuglama i vibro mlinu sa prstenastim radnim elementima. Proces je kontrolisan prosejavanjem na situ 100 μm. Utvrđeno je da se mlevenjem granula MAP veličine ≈3000 μm u laboratorijskom mlinu sa kuglama optimalna krupnoća od 64 % frakcije čestica veličine -100 μm dobija nakon 33 min mlevenja. Za postizanje iste finoće proizvoda u dvostepenom mlevenju vreme je skraćeno na 26 min (10 min u vibro mlinu i 16 min u mlinu sa kuglama). Stabilnost i hidrofobnost SGP je postignuta oblaganjem magnezijum stearatom (MgSt) pri udelu od 2 % u mlinu sa kuglama u trajanju od 15 min. Efikasnost gašenja je testirana na poligonu u realnim uslovima. Na tačno određenom mestu za testiranje, u kontro-lisanim uslovima, izazvan je požar paljenjem čvrstih materijala i zapaljivih tečnosti. U oba slučaja je došlo do trenutne eliminacije plamena. Na taj način je potvrđena efikasnost formiranog SGP i mogućnost njegove upotrebe u praksi

Monolacunary Wells-Dawson Polyoxometalate as a Novel Contrast Agent for Computed Tomography: A Comprehensive Study on In Vivo Toxicity and Biodistribution

Polyoxotungstate nanoclusters have recently emerged as promising contrast agents for computed tomography (CT). In order to evaluate their clinical potential, in this study, we evaluated the in vitro CT imaging properties, potential toxic effects in vivo, and tissue distribution of monolacunary Wells–Dawson polyoxometalate, α2-K10P2W17O61.20H2O (mono-WD POM). Mono-WD POM showed superior X-ray attenuation compared to other tungsten-containing nanoclusters (its parent WD-POM and Keggin POM) and the standard iodine-based contrast agent (iohexol). The calculated X-ray attenuation linear slope for mono-WD POM was significantly higher compared to parent WD-POM, Keggin POM, and iohexol (5.97 ± 0.14 vs. 4.84 ± 0.05, 4.55 ± 0.16, and 4.30 ± 0.09, respectively). Acute oral (maximum-administered dose (MAD) = 960 mg/kg) and intravenous administration (1/10, 1/5, and 1/3 MAD) of mono-WD POM did not induce unexpected changes in rats’ general habits or mortality. Results of blood gas analysis, CO-oximetry status, and the levels of electrolytes, glucose, lactate, creatinine, and BUN demonstrated a dose-dependent tendency 14 days after intravenous administration of mono-WD POM. The most significant differences compared to the control were observed for 1/3 MAD, being approximately seventy times higher than the typically used dose (0.015 mmol W/kg) of tungsten-based contrast agents. The highest tungsten deposition was found in the kidney (1/3 MAD—0.67 ± 0.12; 1/5 MAD—0.59 ± 0.07; 1/10 MAD—0.54 ± 0.05), which corresponded to detected morphological irregularities, electrolyte imbalance, and increased BUN levels

Hospital infections rate and health staff density in a neonatology department

© 2017, Serbian Medical Society. All rights reserved. Objective. The aim of our study was to compare staffing trends for physicians and nurses with hospital infections (HIs) rate at a neonatology department of tertiary care health facility. Methods. The prospective cohort study was conducted at Neonatology Department, Clinical Centre Kragujevac, Serbia. The incidences of neonates with HIs were calculated for each of the quarters during the 5-year period. The data about the number and structure of staff for each quarter of the study period were collected from the official work schedule lists of the department. Results. This study registered a total of 272 HIs occurring in 264 neonates. The incidence rate of patients with HIs was 13.36% and the incidence density of HIs was 5.85 per 1,000 patient-days. In the observed period the trend of incidence rate of patients with HIs was stable, but the trend of incidence density of HIs was increasing, however without statistical significance. The highest incidence rates of patients with HIs were recorded in the third quarter of all observed years respectively: 17.44% in 2012, 16.74% in 2013, 23.47% in 2014, 18.18% in 2015 and 22.74 in 2016. The average number of nurses in the first shift ranged from 5.0 to 7.0, but in second shift was 3.0 to 4.0 only, and the least number of nurses worked in the third quarter of each year. The average number of physicians in the first shift ranged from 2.33 to 4.47 and they were also the fewest in numbers in the third quarter. We observed strong negative correlation between the average incidence rate of patients with HIs and the average number of nurses in the first shift (r=-0.977, p=0.023). Conclusion. Optimal nurse and physician staffing of neonatal departments in developing countries and the avoidance of inter-quarter variations in number of staff at duty would decrease the incidence of HIs and probably create overall savings of the hospital budget

Applications of Higuchi's fractal dimension in the analysis of biological signals

Significant contribution to understanding of complex biological systems emerged from application of fractal analysis. This paper presents a fractal analysis as one of many mathematical methods in the analysis of biological signals. Higuchi's fractal dimension is used in stationary and quasi-stationary bio-signals (EEG, ECoG) analysis and appropriately modified in the analysis of the bimodal pattern of neuronal activity as non-stationary signals

The identification and quantification of bioactive compounds from the aqueous extract of comfrey root by UHPLC-DAD-HESI-MS method and its microbial activity

In this study the qualitative, quantitative and microbial determination of the aqueous extract of comfrey root was done. The qualitative and quantitative analyses were done by the UHPLC-DAD-HESI-MS method. As major bioactive compounds, allantoin, rosmarinic acid and ellagic acid were identified and their quantification was also done. The obtained results showed a high content of allantoin, ellagic acid and rosmarinic acid (8.91, 7.4 and 12.8%, respectively) which indicated that the comfrey root can be used as a source for the isolation of these three compounds. The results obtained by the determination of the antimicrobial activity showed that Escherichia coli ATCC8739 and Salmonela typhimirium ATCC6538 were most sensitive to the aqueous extract of comfrey root. The results showed that allantoin did not express the antimicrobial activity on all the investigated bacteria species, and based on this it can be concluded that allantoin is not responsible for the antimicrobial activity of the aqueous extract of comfrey root. [Projekat Ministrstva nauke Republike Srbije, br TR-34012