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Open access

Dragan M. Pavlović, Merdin Š. Markišić and Aleksandra M. Pavlović

Abstract

Vitamins are necessary factors in human development and normal brain function. Vitamin C is a hydrosoluble compound that humans cannot produce; therefore, we are completely dependent on food intake for vitamin C. Ascorbic acid is an important antioxidative agent and is present in high concentrations in neurons and is also crucial for collagen synthesis throughout the body. Ascorbic acid has a role in modulating many essential neurotransmitters, enables neurogenesis in adult brain and protects cells against infection. While SVCT1 enables the absorption of vitamin C in the intestine, SVCT2 is primarily located in the brain.

Ascorbate deficiency is classically expressed as scurvy, which is lethal if not treated. However, subclinical deficiencies are probably much more frequent. Potential fields of vitamin C therapy are in neurodegenerative, cerebrovascular and affective diseases, cancer, brain trauma and others. For example, there is some data on its positive effects in Alzheimer’s disease. Various dosing regimes are used, but ascorbate is safe, even in high doses for protracted periods. Better designed studies are needed to elucidate all of the potential therapeutic roles of vitamin C.

Open access

Jovana Veljković, Jelena Brcanović, Aleksandra Pavlović, Snežana Mitić, Biljana Kaličanin and Milan Mitić

Summary

While there is a large number of scientific papers reporting chemical composition and biological activities of Aronia melanocarpa, there is a lack information regarding the commercially available bagged tea. In order to supply new information on the antioxidant activity of the Aronia melanocarpa tea infusions, the aim of this study was to evaluate individual phenolic compounds which could be responsible for antioxidant activities of these beverages.

Selected anthocyanins (cyanidin-3-O-galactoside, cyanidin-3-O-glucoside, cyanidin- 3-O-arabinoside, and cyanidin-3-O-xyloside), gallic acid, caffeic acid, rutin, morin, and protocatechuic acid were simultaneously detected from commercially available tea infusions using a High Performance Liquid Chromatographic (HPLC) method. The antioxidant activity was measured using five in vitro spectrophotometric methods: 1,1-diphenyl- 2-picrylhydrazyl radical scavenging activity (DPPH), 2,2'-azino-bis (3-ethylbenzthiazoline- 6-sulphonic acid) radical cation scavenging activity (ABTS), ferric reducing-antioxidant power (FRAP) and reduction power (RP)Fe(III) to Fe(II).

Obtained results showed that anthocyanins, predominantly of cyanidin-3-O-galactoside, are the major class of polyphenolic compounds in tea infusions. Among phenolic acids the most abundant is caffeic acid. A significant correlation between DPPH and ABTS and FRAP and RP suggested that antioxidant components in these beverages were capable scavenging free radicals and reducing oxidants.

Generally, these beverages had relatively high antioxidant capacities and could be important dietary sources of antioxidant phenolics for the prevention of diseases caused by oxidative stress.

Open access

Aleksandra Klisic, Gordana Kocic, Nebojsa Kavaric, Radmila Pavlovic, Ivan Soldatovic and Ana Ninic

Abstract

Background: Nitric oxide (NO) is oxidative stress biomarker which is regarded as one of the key determinants of energy metabolism and vascular tone. Considering the controversial reports on the association between nitric oxide products (NOx) and metabolic syndrome (MetS), the aim of the current study was to examine that potential relationship. Additionally, we aimed to evaluate a broad spectrum of other oxidative stress biomarkers [i.e., malondialdehyde (MDA), advanced oxidation protein products (AOPP), xanthine oxidoreductase (XOD), xanthine oxidase (XO) xanthine dehydrogenase (XDH)] in relation with MetS. Methods: A total of 109 volunteers (46.8% of them with MetS) were included in this cross-sectional study. Bio - hemical and anthropometric parameters, as well as blood pressure, were obtained. The MetS was diagnosed according to the International Diabetes Federation criteria. Results: Multivariate logistic regression analysis showed that XOD (OR=1.011; 95% CI 1.002-1.019; p=0.016), XO (OR=1.014; 95% CI 1.003-1.026; p=0.016), MDA (OR=1.113; 95% CI 1.038-1.192; p=0.003) and AOPP (OR=1.022; 95% CI 1.005-1.039; p=0.012) were the independent predictors of MetS, whereas no association between NOx and MetS was found. As XOD rose for 1 U/L, XO for 1 U/L, MDA for 1 mmol/L and AOPP for 1 T/L, probability for MetS rose for 1.1%, 1.4%, 11.3% and 2.2%, respectively. Adjusted R2 for the Model was 0.531, which means that 53.1% of variation in MetS could be explained with this Model. Conclusion: Unlike XOD, MDA and AOPP, NOx is not associated with MetS.

Open access

Snezana Tosic, Gordana Stojanovic, Snezana Mitic, Aleksandra Pavlovic and Sladjana Alagic

Abstract

The aim of this work was to determine the content of 22 macro- and microelements in ten raw Serbian propolis samples which differ in geographical and botanical origin as well as in polluted agent contents by atomic emission spectrometry with inductively coupled plasma (ICP-OES). The macroelements were more common and present Ca content was the highest while Na content the lowest. Among the studied essential trace elements Fe was the most common element. The levels of toxic elements (Pb, Cd, As and Hg) were also analyzed, since they were possible environmental contaminants that could be transferred into propolis products for human consumption. As and Hg were not detected in any of the analyzed samples but a high level of Pb (2.0-9.7 mg/kg) was detected and only selected portions of raw propolis could be used to produce natural medicines and dietary supplements for humans. Obtained results were statistically analyzed, and the examined samples showed a wide range of element content.

Open access

Dragana Savić, Aleksandra Simović, Radiša Pavlović, Sanja Knežević, Nevena Folić, Bojana Trikoš, Zorana Đorđević and Zoran Igrutinović

ABSTRACT

In absence of clear clinical signs and clear defi nition, neonatal sepsis is still one of the major cause of morbidity and mortality. Most researchs in past time was directional on fi nding new biomarkers with greater sensitivity and specifi city in detection of neonatal sepsis. Th e aim of our study was to investigate if presepsin obtained from tracheal asprate in intubated newborns, can be a novel biomarker of systemic bacterial infection. Our ‘’case control’’ study included 60 newborns, 11 with suspected neonatal sepsis. Tracheal aspirate for examination was taken in the usual toilets, in aseptic conditions, by lavage with 2 ml of 0.9% NaCl in Mucus suction set. In the same day were mesured presepsin (blood), CRP, PCT, leukocytes and neutrophyls, as well as blood culture. Our research showed higher levels for PCT and presepsin (blood) in septic newborns, as well as in newborns with clinical signs of SIRS. Presepsin obtained from a tracheal aspirate had high score for septic newborns. As the coeffi cients of simple linear correlation showed, there was quantitative agreement between presepsin (blood) with presepsin (tracheal aspirate)- increase in the value of one leads to an increase in other. In conjunction with an already validated markers of infection, presepsin obtained from tracheal aspirate cam be turned on in diagnostic procedures.

Open access

Đuka Ninković Baroš, Jagoda Balaban, Svetlana Tomašević Pavlović, Aleksandra Salapura Dugonjić, Gorana Popović and Dušanka Brđanin

Abstract

We present a 46-year-old non-atopic HIV-negative woman from Doboj, Republic of Srpska, Bosnia and Herzegovina, who was referred to the Department of Dermatovenereology, Clinical Center Banja Luka, Republic of Srpska, Bosnia and Herzegovina, with a 3-month long history of an erythematous, large indurated infl amed area on the upper arm. The condition was asymptomatic, immediately following surgical excision of a small tumor. After exlusion of pulmonary blastomycosis and other organ involvement, the diagnosis of primary inoculation cutaneous blastomycosis was made based on clinical presentation and histopathological fi ndings. Histopathology revealed thick-walled, rounded, budding yeasts with broad-based buds that stained pink with periodic acid-schiff (PAS) staining. Itraconazole therapy was initiated at a dose of 2x100 mg/day. After three months of therapy, the dose of itraconazole was increased to 2x200 mg/day during the next three months, and then the dose was reduced to 2x100 mg. Blastomycosis is an uncommon, chronic granulomatous and suppurative mycosis caused by Blastomyces dermatitidis, which belongs to the group of main endemic systemic mycoses and in the great majority of cases represents a primary pulmonary disease. Few sporadic cases have been reported in Europe. There are three forms of blastomycosis: primary cutaneous, pulmonary and disseminated. B. dermatitidis has rarely been isolated from the environment. Wood debris or land close to rivers or subject to fl ooding are considered to be the natural substrate. The fungus can grow in sterile soil in the laboratory, and it is believed that humans get infected by inhaling spores from a saprophytic source. Primary cutaneous blastomycosis is very rare and it is found in farmers and laboratory workers. Human to human transmission does not normally occur. The diagnosis of the skin lesions is made by direct microscopy of skin samples (e.g., pus, scrapings) with 10% potassium hydroxide mount and confi rmed by culture or biopsy. Histopathological analysis provides identifi cation of all the dimorphic fungi. However, this can be complicated by the fact that in some cases they can be morphologically atypical or sterile. In the tissues, B. dermatitidis produces characteristic thick-walled, rounded, refractile, and spherical budding yeasts with broad-based buds. Of the available antimycotic drugs, itraconazole 200 mg/day is probably the most effective, but at least 400 mg/day is redommended initially.

Open access

Ivana Novaković, Nela Maksimović, Aleksandra Pavlović, Milena Žarković, Branislav Rovčanin, Duško Mirković, Tatjana Pekmezović and Dragana Cvetković

Summary

Molecular genetic testing is part of modern medical practice. DNA tests are an essential part of diagnostics and genetic counseling in single gene diseases, while their application in polygenic disorders is still limited. Pharmacogenetics studies DNA variants associated with variations in drug efficacy and toxicity, and tests in this field are being developed rapidly. The main method for molecular genetic testing is the polymerase chain reaction, with a number of modifications. New methods, such as next generation sequencing and DNA microarray, should allow simultaneous analysis of a number of genes, even whole genome sequencing. Ethical concerns in molecular genetic testing are very important, along with legislation. After molecular genetic testing, interpretation of results and genetic counseling should be done by professionals. With the example of thrombophilia, we discuss questions about genetic testing, its possibilities and promises.

Open access

Tatjana Cvetković, Radmila Pavlović, Vidosava Đorđević, Ivana Stojanović, Radmila Veličković-Radovanović, Aleksandra Ignjatović, Nikola Stefanović, Slavoljub Živanović and Vidojko Đorđević

Summary

Decreased nitric oxide (NO) production and/or impaired NO bioavailability may occur in patients with the chronic kidney disease (CKD), and could contribute to elevation of blood pressure, cardiovascular disease (CVD) and progression of renal injury in these patients. Free guanidinomethylated arginine residues occur endogenously as a result of proteolysis of post-translational methylated tissue proteins. The asymmetric dimethyl arginine (ADMA) is a competitive inhibitor of the nitric oxide synthase (NOS) enzymes. The kidney has a predominant role in ADMA elimination by combining two mechanisms; urinary excretion and metabolization of ADMA The degradation of ADMA is accomplished intracellularly by the enzyme dimethylarginine dimethylaminohydrolase (DDAH). ADMA is not only a uremic toxin, but also a strong marker of the endothelial dysfunction and atherosclerosis and a stronger independent predictor of all-cause mortality and cardiovascular outcome in patients with the chronic renal failure. There are at least four mechanisms that may explain the accumulation of ADMA in CKD: increased methylation of proteins, increased protein turnover, decreased metabolism by DDAH and impaired renal excretion. A strong positive correlation between symmetric dimethyl arginine (SDMA) and creatinine suggests that SDMA might be of value as a marker of the renal function. Reduced NO elaboration secondary to accumulation of ADMA and elevated inflammation may be important pathogenic factors for endothelial dysfunction in patients with the renal disease. Elevation of ADMA may be a missing link between CVD and CKD.

Open access

Tatjana Cvetković, Radmila Veličković-Radovanović, Dijana Stojanović, Nikola Stefanović, Aleksandra Ignjatović, Ivana Stojanović, Nikola Sladojević and Dušica Pavlović

Summary

Background: The aim of the study was to evaluate parameters of oxidative and nitrosative stress as well as antioxidative parameters in a group of renal transplant recipients with stable graft function and no clinical signs of cardiovascular disease. We also aimed to determine the correlations among these parameters and to evaluate potential differences in all the biomarkers with regard to the immunosuppression protocol.

Methods: We enrolled 57 renal transplant recipients and 31 controls who were age and sex matched with the renal transplant recipients. All of the patients included in this study had post-renal transplant surgery at least 12 months earlier and were on standard immunosuppressive therapy. In this study, we determined thiobarbituric acid-reactive substances in plasma and red blood cells and advanced oxidation protein products, nitrosative stress parameters (asymmetric and symmetric dimethylarginine - ADMA and SDMA), and antioxidative parameters (total SH groups and catalase activity).

Results: The results of our study demonstrated that the levels of oxidative and nitrosative stress were significantly increased compared to the healthy population (p<0.01 except for plasma catalase activity p<0.05). Correlation analysis showed significant positive correlations between: ADMA and SDMA (p<0.01); ADMA and nitrates (p<0.05); SDMA and nitrates (p<0.05); between OS parameters in the experimental group; AOPP and SH groups (p<0.05) and TBARS in plasma and SH groups (p<0.01), SDMA and AOPP (p< 0.05); SDMA and TBARS in plasma (p<0.05); SDMA and SH groups (p<0.01); nitrates and SH groups (p<0.05).

Conclusion: There was no significant difference in oxidative and nitrosative stress parameters with respect to the immunosuppressive protocol.

Open access

Zorica Bulat, Danijela Đukić-Ćosić, Biljana Antonijević, Aleksandra Buha, Petar Bulat, Zoran Pavlović and Vesna Matović

Abstract

The study was designed to investigate the influence of zinc (Zn) supplementation on cadmium-induced alterations in zinc, copper (Cu), and magnesium (Mg) status in rabbits. For this purpose, the concentrations of cadmium (Cd), Zn, Cu, and Mg were estimated in the blood, liver, kidney, and bone. The rabbits were divided in a control group, a Cd group-animals intoxicated orally with Cd (10 mg kg-1 bw, as aqueous solution of Cd-chloride), and a Cd+Zn group-animals intoxicated with the same dose of Cd and co-treated with Zn (20 mg kg-1 bw, as aqueous solution of Zn-sulphate). Solutions were administered orally, every day for 28 days. Sample mineralisation was performed with concentrated nitric acid (HNO3) and perchloric acid (HClO4) (4:1) and metal concentrations were determined by atomic absorption spectrophotometry (AAS). Zinc supplementation improved some of Cd-induced disturbances in bioelement levels in the investigated tissues. Beneficial effects of Zn on Zn and Cu levels were observed in blood, as well as on the Cu kidney level. The calculated values for Cu/Zn, Mg/Zn, and Mg/Cu ratios in blood suggest that Zn co-treatment reduces Cd-induced changes in bioelement ratios in blood.