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Open access

Ivana Stojanović, Ankica Jelenković, Ivana Vasiljević, Dušica Pavlović and Gordana Bjelaković

Spermine and L-Name Pretreatment Effects on Polyamine and Nitric Oxide Metabolism in Rat Brain During Seizures

In the CNS polyamines can exert opposite effects, depending on the concentration and conditions in the cell. Protective or neurotoxic polyamine effects were documented during seizures and repeated CNS excitation. Intensive research of exogenous polyamines effects during seizures induced by numerous agents did not clear up confusions about the duality of effects and the role of polyamines in seizures. In order to understand polyamine modulatory effects in seizures, the importance of NO and polyamine metabolism interdependence and the possible implication of changes of postulated NO and polyamine equillibrium in seizures, the effects of spermine alone and in combination with L-NAME (NOS inhibitor) on seizures induced by pentazol (PTZ) were investigated. To compare the obtained results, the effects of anticonvulsant midazolam on NO production during seizures were also investigated. Seizures were induced by i.p. application of pentazol (100 mg/kg b.w.). Spermine and L-NAME were administered i.p. before PTZ. In the striatum and hippocampus, spermine induced increased NO production (p<0.001) related to values in the group treated by PTZ. Application of L-NAME before spermine and PTZ caused decrease of NO production in comparison with animals treated only by PTZ or spermine and PTZ. L-NAME given before spermine exerts protective effects related to seizures induced by PTZ and to the group treated by spermine, extending the time of seizure symptoms appearance, thus confirming the NO signaling system involvement in spermine effects during seizures. Highly significant PAO activity increase caused by spermine points out the intensified interconversion of spermine into putrescine, in order to maintain the intracellular putrescine concentration. The obtained results prove a strong relationship between the NO signaling system and polyamine metabolism in the brain during seizures and the importance of their changes in this kind of CNS injury.

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

Gordana Andjelic, Svetlana Jovanovic, Snezana Pesic, Milos Mitrasevic, Jasmina Stojanovic, Filip Radotic, Dusan Todorovic and Nenad Petrovic

Abstract

To investigate the efficacy of a posterior sub-Tenon’s capsule triamcinolone injection for treating eyes with non-infectious posterior and intermediate uveitis.

A total of 31 eyes from 20 patients with non-infectious posterior uveitis and 18 eyes from 10 patients with non-infectious intermediate uveitis that inadequately responded to treatment with systemic corticosteroids and second-line immunosuppressive agents were enrolled in the study. All patients received a posterior sub-Tenon’s injection of 20 mg/ml triamcinolone. The parameters we examined included the following: best corrected visual acuity, central foveal thickness, fluorescein angiography score and intraocular pressure.

The mean best corrected visual acuity was significantly improved from the control visit, 0.15±0.30 logMAR (Snellen equivalent 0.7), compared to the baseline measurements, 0.60±0.30 logMAR (Snellen equivalent 0.25; P<0.05). The mean central foveal thickness (CFT) and the mean score for fluorescein angiography (FA) were significantly decreased from the baseline (CFT: 320±34 μm; FA mean score: 5.9±1.9) compared to the twelve-week control visit (CFT: 235±30 μm; FA mean score: 1.2±1.1; P<0.001). Five eyes had intraocular pressure spikes that required a topical anti-glaucomatous treatment.

A posterior sub-Tenon’s injection of triamcinolone can significantly improve visual acuity and decrease macular oedema in patients with non-infectious posterior and intermediate uveitis. Complications were minimal, and there were no eyes that required surgical treatment for elevated intraocular pressure. The results suggest that the posterior sub-Tenon’s injection of triamcinolone is an important form of therapy for non-infectious posterior and intermediate uveitis.

Open access

Dusan Lj. Tomovic, Andriana M. Bukonjic, Aleksandar Kocovic, Milos V. Nikolic, Marina Z. Mijajlovic, Verica V. Jevtic, Zoran R. Ratkovic, Aleksandar N. Arsenijevic, Jelena Z. Milovanovic, Bojana Stojanovic, Srecko R. Trifunovic and Gordana P. Radic

Abstract

New complexes of copper(II) with S-alkenyl derivatives of thiosalicylic acid (alkenyl = propenyl-(L1), isobutenyl-(L2)) have been synthesized and characterized by microanalysis, infrared spectra, magnetic measurements, and by NMR spectra. The cytotoxic activity of two newly synthesized precursor S-alkenyl derivatives of thiosalicylic acid were tested using an MTT colorimetric technique on HCT-116 human colon carcinoma cells. The cytotoxic effect of the copper(II)- complexes were higher compared to the cytotoxicity of the corresponding ligand (for concentrations from 31.25 to 250 μM). Copper(II)-complexes showed a slightly lower cytotoxicity compared to cisplatin. Complexes of copper(II) with S-alkenyl derivatives of thiosalicylic acid (at concentrations from 250 to 1000 μM) had a cytotoxic effect on HCT-116 cells compared to cisplatin.

Open access

Jelena Radović, Jelena Vojinović, Vladmila Bojanić, Tatjana Jevtović-Stoimenov, Gordana Kocićs, Maja Milojković, Andrej Veljković, Ivana Marković, Svetlana Stojanovic and Dušica Pavlović

Summary

Background: Episodic fever syndromes are commonly seen in pediatric practice. Episodic fever of unknown origin (FUO) lasts for a few days or weeks and is followed by a fever-free period with a sense of well-being. In this condition, activated neutrophils and monocytes intensively generate reactive oxidative species that may further damage various mole- cules. The aim of the study was to evaluate oxidative stress biomarkers, lipid peroxidation in erythrocytes and plasma, and advanced oxidation protein products (AOPP) in children with episodic FUO.

Methods: The study enrolled 25 children with episodic FUO in afebrile phase and 25 healthy children as controls. Lipid peroxidation was evaluated by measuring malondialdehyde (MDA) production with the thiobarbituric-acid-reactive sub- stances (TBARS) assay in erythrocytes and plasma. Oxidative modification of proteins was measured spectrophotometri- cally by the determination of AOPP in plasma.

Results: Mean duration of episodic fevers was 3.96±2.8 years. Erythrocyte MDA levels were higher in children with FUO than in controls (86.26± 10.75 vs. 78.0±3.21 nmol/g hemoglobin), although not significantly (p=0.202). The MDA plasma concentrations were similar (2.42±0.35 vs. 2.41 ±0.39 (xmol/L) between the groups (p=0.732). Unexpectedly, levels of AOPP were significantly lower in chil- dren with FUO than in healthy controls (18.8±5.04 vs. 25.1 ±3.35 nmol/L, p=0.047).

Conclusions: Episodic fevers of unknown origin with an aver- age duration of 3.96±2.8 years do not cause significant oxidative modifications of lipids and proteins in children.

Open access

Milena Jurisevic, Gordana Radosavljevic, Aleksandar Arsenijevic, Marija Milovanovic, Nevena Gajovic, Dragana Djordjevic, Jelena Milovanovic, Bojana Stojanovic, Aleksandar Ilic, Tibor Sabo and Tatjana Kanjevac

Abstract

The design of platinum based drugs is not a new field of interest. Platinum complexes are widely used as anticancer agents and currently, approximately 30 platinum(II) and platinum(IV) entered into some of the phases of clinical trials. A special place in today’s research belongs to platinum complexes with diammine ligands. A large number of edda (ethylenediamine- N, N’-diacetate)-type ligands and their corresponding metal complexes has been successfully synthesized. This article summarizes recent progress in research on edda-type-platinum complexes. Some of these agents achieves better effect compared to the gold standard (cisplatin). It has been shown that there is a possible relationship between the length of the ligand ester group carbon chain and its cytotoxic effect. In most cases the longer the ester chain is the greater is the antitumor activity. Of particular interest are the noticeable effects of some new platinum compound with edda-type ligand on cell lines that are known to have a high level of cisplatin-resistance. Exanimate complexes appear to have a different mode of mechanism of action compared with cisplatin which includes apoptotic and necrotic cell death. There are indications that further investigations of these compounds may be very useful in overcoming the problems associated global cancer statistic.