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  • Author: Vladimir Popović x
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Summary

The purpose of this paper is to analyse the introduction of certain plant species such as pot marigolds (Calendula officinalis L.) into neglected and predominantly urban spaces in the Republic of Serbia. The research was based on the results obtained in a two-year experiment conducted in the vicinity of the Novi Sad-Backa Palanka road. The primary objective of the experiment was to examine the behaviour of pot marigolds in poor-quality and neglected soils, with minimum cultural practices, in order to obtain novel plants in such adverse environments, which could be subsequently marketed in Serbia. The experiment commenced in 2014 by planting pot marigolds in plots previously cleared of weeds by mechanical tilling. In the spring of 2015, pot marigold seedlings, i.e. the first generation of plants obtained from the plots created in 2014, were planted in weed-free plots. The measurements were performed in three replicates from 10 October to 10 December 2015 in order to determine the number of volunteer plants, which could be further improved in nursery production and subsequently marketed in Serbia. The results obtained indubitably indicate that this and prospective studies exert positive ecological, agricultural and economic effects on a vast range of potential users.

Abstract

The aim of this study is to describe the morphological characteristics, the number of roots and number of root canals of mandibular central incisors, lateral incisors and canines, and the relationship of these characteristics with the sex and the jaw side where the tooth is located, in the Serbian population using cone-beam computed tomography (CBCT).

CBCT images of a total of 902 mandible front teeth, including 296 central incisors, 294 lateral incisors and 312 canines were analyzed in the database. For assessing the morphology of the root canal, Vertucci method of classification was used.

Central incisors had two canals in 27%, similar as lateral incisor which had two canals in 26.5%. Mandibular canines had two canals in 7.1% and there was a significant difference between genders. The most prevalent root canal configuration type in all mandibular anterior teeth was type I. In the groups of mandibular incisors with two root canals the most common was type III. In the group of mandibular canines with two root canals, type V had the greatest occurrence.

Most mandibular anterior teeth had one root canal. Two root canals were found in 27% of the mandibular incisors. There is a significant difference in root morphology between genders. It is important for dental practitioner to expect different morphological variations when performing endodontic treatment. More studies are needed to further define morphological characteristics of roots of mandibular anterior teeth in Serbian population.

Summary

Background/Aim: Metastatic tumours make up only 1-3% of all malignant tumours of the oral region; however, in 25% of the total number of cases, they are the first sign of the disease. Usually, metastases in the oral region are followed by poor prognosis. Metastases are more common in the mandible than in the maxilla; in soft tissues, they most commonly occur in the attached gingiva and tongue. Malignant tumours of the lung, breast, kidney, liver, bone, prostate, thyroid gland, skin, colon and female genital organs most commonly give metastases in this region, usually in patients aged 40 to 70 years.

Case Report: We present a patient aged 79 years with a tumour change in the body of the tongue. After histopathological and immunohistochemical analysis (Cytokeratin, Vimentin, CD 10 positive tumour cells, Cytokeratin 7, Cytokeratin 20 negative tumour cells), there was a suspicion of metastasis of clear cell renal carcinoma (CCRC). Due to renal cancer, the patient had left kidney operated seven years before the diagnosis of tongue tumour.

Conclusions: Diagnosis of metastatic tumours of the oral region is a great challenge, both for clinicians and for histopathologists. Since it is a heterogeneous group of neoplasms, standard histopathological tissue processing, is not always sufficient to determine the histological type of tumour and its primary origin. In the analysis of metastatic tumours of the oral region, team work is important and careful clinical and histopathological assessment lead to definitive and accurate diagnosis.

Abstract

Detailed limnological study of the Lake Srebrno (Serbia) bottom fauna was performed in March 2007. Investigations included qualitative, quantitative, and saprobiological analysis of bottom fauna communities, physical and chemical analysis of sediments and determination of chlorophyll a concentration, as well as saprobic and trophic status analyses. Samples were collected at eighteen sites distributed along a shoreline and in deeper sections of the lake. Twenty taxa from nine macroinvertebrate groups were recorded. Family Chironomidae had the biggest index of participation, the highest species diversity and the largest density of populations in benthocenoses of Lake Srebrno. Faunistic similarity between sites was estimated according to Sorensen’s Quotient of Similarity (QS). The majority of benthocenoses - 56% showed a medium level of faunistic similarity (QS = 21-60%), and 42% of benthocenoses showed a high level of faunistic similarity (QS = 61-100%). The classification of Lake Srebrno based on saprobic and trophic levels was assessed. Saprobic level was in the range from alpha-meso- to poly-alpha-mesosaprobity. The water quality of the lake ranged from class III and between IV and III class. Generally, Lake Srebrno had eutrophic status with the gradation to hypertrophy.

Abstract

Since the early 1940s, a significant amount of research has been conducted to describe the impact of the high-G acceleration on the cardiovascular system. The objective of the present study was to examine the role of the antioxidant enzyme system under biodynamic stress in the liver, heart and gastric mucosa in response to high-magnitude +Gz exposure in a rat model. Twenty adult male Wistar albino rats (10 rats per group; 9-11 weeks old, 200-250 g b.w.) were divided into the following two groups: control and G (exposed to a biodynamic stress model under positive (+7 Gz) acceleration for 40 s). The influence of acute biodynamic stress on pro-oxidative parameters in the rat liver (xanthine oxidase (XOD), catalase (CAT), peroxidase (Px), glutathione peroxidase (GSH-Px), total content of glutathione (GSH), lipid peroxidation (LPx)) and on histopathological alterations in the liver, cardiac muscle and gastric mucosa was examined. Biodynamic stress resulting from positive (+7 Gz) acceleration resulted in a highly statistically signifi cant increase of CAT GSH-Px activity compared to the control group. The LPx levels were significantly decreased, but the GSH contents and the activities of other enzymes were not significantly changed. Significant microscopic changes in the liver, heart and gastric mucosa were observed in the G group. These results clearly indicate that +Gz acceleration alters biochemical systems. These alterations in cellular processes may be mediated by influences of hypoxia or ischaemia via changes in the antioxidant capacity.

Abstract

Provinols are an alcohol-free extract of red wine that contains a wide range of polyphenols. Polyphenols are a group of chemical compounds found in diverse plants. Polyphenols are considered to protect against cardiovascular disease. Although some older epidemiological studies have indicated that the positive effects of red wine on heart disease can be attributed to the alcohol content alone, there is now powerful evidence that polyphenols present in red wine are responsible for these positive effects. The hearts of male Wistar albino rats (n = 36, 12 in each experimental group, 10 weeks old, body mass 250 ± 30 g) were excised and retrogradely perfused according to the Langendorff technique at a gradually increasing perfusion pressure (40-120 cmH2O). Parameters of cardiac function (dp/dt max, dp/dt min, SLVP, DLVP, HR, CF) were measured after perfusion with three different concentrations of provinols (5 μg/ml, 10 μg/ml and 50 μg/ml). Administration of the highest dose (50 μg/ml) induced a significant increase in dp/dt max, dp/dt min, HR and CF compared with control conditions at CPP = 40 cmH2O, while an intermediate dose increased dp/dt max at the same CPP. Generally viewed, the results of the present study suggest that provinols may have a beneficial effect on the intact myocardium and coronary circulation. These findings could constitute an important step in further investigation of these polyphenols under different representative experimental conditions in the heart, as well as providing a good basis for potential clinical studies in this field.

Abstract

In this paper we analyze the influence of users’ density distribution in one cell of CDMA mobile network (ie adjusted power control on the forward link) on base station emission power. This influence is analyzed for different circles radii around base station within which same emission power is generated for all mobile users, and for different values of propagation loss coefficient. It is proved that emission power in this cell must be increased comparing to the similar cell, which uses complete power control. The power increase is greater when greater number of users are situated near base station, and for greater values of propagation loss coefficient. The results are presented, illustrated by numerical examples and verified by simulation for three users’ density distributions: uniform, decreasing and increasing density from the base station to the cell rim. The simulation process, which is based on random traffic process, is presented briefly.

Abstract

The effect of scuba diving on ROS production and oxidative stress compared to that of other recreational activities is still poorly understood. The aim of this study was to assess the influence of different types of physical activity on the redox status of scuba divers by testing the pro- and anti-oxidative parameters immediately before and after different types of physical load. The prevalence study included 10 professional police divers. All examinees were male, 32 ± 5.1 years of age, well-trained, and with a minimum of five to a maximum of 20 years of diving experience. The study was divided into three experimental protocols: 1) an exercise test (at atmospheric pressure), 2) an at sea dive (30 meters for 30 minutes), and 3) a dive into river current (10 meters for 30 minutes). Immediately before and after the load test of the divers at atmospheric pressure and immediately before and after the dive, blood samples were taken to determine the values of the following pro-oxidant markers: O2 , H2O2, NO2 and TBARS, as well as antioxidant enzymes (SOD and CAT). A comparison of the results before and after physical activity for all three protocols revealed a significant increase in values for NO2 , O2 , H2O2 and CAT after physical activity. It can be concluded that the values of all oxidative stress markers depend on the season of the year in which the research is conducted or on the frequency of dives and degree of physical exertion during this period of the year.

Abstract

The aim of our study was to stablish the possible alternations in fatty acid composition of brain phospholipids in rats on a standard and high-fat diet supplemented with buckwheat leaf and flower mixture (BLF) and subsequent possible beneficial effects of BLF. Four months old male Wistar rats were randomly divided into five experimental groups fed a standard diet, standard diet supplemented with 5% BLF, high-fat diet, high-fat diet with full-period (13 weeks) of 5% BLF supplementation and high-fat diet with partial-period (7 weeks) of 5% BLF supplementation. Gas-liquid chromatography was performed to analyze the fatty acids in hexane lipid extracts of whole rat brains.

Supplementation with BLF did not induce significant changes in fatty acid composition of whole brain phospholipids in rats fed the standard diet. In rats on high-fat diet concomitant (full-period) BLF supplementation increased eicosapentaenoic acid (20:5n-3, EPA), total n-6 and n-6/n-3 ratio, and decreased the percentage of oleic acid (18:1n-9) and estimated activity of Δ-9 desaturase. When BLF application was postponed (partial-period) in the case of developed hyperlipidemia, a decrease of stearic acid (18:0) accompanied with an increased estimated Δ-9 desaturase activity was observed. Regardless of BLF supplementation all high-fat diet-fed groups showed an elevated percentage of linoleic acid (18:2n-6, LA) and a reduced estimated Δ-6 desaturase activity.

BLF contributes to the maintenance of stable fatty acid composition of brain phospholipids and supports normal brain function in high-fat diet rats, with more positive effects when BLF was applied before hyperlipidemia developed. This could be the mode of buckwheat health beneficial effects on the brain.