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The aim of this study was to assess the spatial distribution of arsenic and heavy metals (Cd, Cr, Cu Hg, Ni, Pb and Zn) in a riparian area influenced by periodical flooding along a considerable stretch of the Danube River. This screening was undertaken on soil and plant samples collected from 43 sites along 2386 km of the river, collected during the international Joint Danube Survey 3 expedition (ICPDR, 2015). In addition, data on the concentration of these elements in river sediment was used in order to describe the relationship between sediment, riparian soil and riparian plants. A significant positive correlation (Spearman r, for p<0.05) was found for trace metal concentrations in river sediment and soil (r=0.817). A significant correlation between soil and plants (r=0.438) and sediment and plants (r=0.412) was also found for trace metal concentrations. Elevated levels of Cd, Cr, Cu, and Ni were found at certain sites along the Serbian stretch, while elevated concentrations of Hg were also detected in Hungary, of Pb along the Romanian stretch and of As along the Bulgarian stretch (the Lower Danube). These results point to the presence of naturally-occurring metals derived from ore deposits in the Danube River Basin and anthropogenic metals, released by mining and processing of metal ores and other industrial facilities, which are responsible for the entry of metals such as Cu, Ni and Zn. Our results also indicated toxic Cd and Zn levels in plant samples, measured at the Hercegsznato site (Middle Danube, Hungary), which highlighted these elements as a potential limiting factor for riparian vegetation in that area. The distribution of the analysed elements in plant material also indicates the species-specific accumulation of trace metals. Based on our results, the Lower and Middle Danube were found to be more polluted in terms of the analysed elements.

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Concentrations of four heavy metals were determined in tree leaves and bark collected from polluted and non-polluted areas of three European cities (Salzburg, Belgrade and Thessaloniki) for a comparative study. Platanus orientalis L. and Pinus nigra Arn., widespread in urban northern and southern Europe, were tested for their suitability for air quality biomonitoring. Leaves and barks were collected uniformly of an initial quantity of about 30 g of each sample. Analysis was accomplished by electrothermal atomic absorption spectrometry after total digestion. Site-dependent variations were found with the highest concentration level measured in Belgrade, followed by Thessaloniki and Salzburg. A higher accumulation of heavy metals was found in bark compared to leaves. Pine tree bark, accumulating higher concentrations of trace metals compared to plane tree bark, shows a higher efficiency as bioindicator for urban pollution. Both indicator species are suitable for comparative studies on bioindication of urban air pollution.

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This study examined the leaf Pb content, chlorophyll fluorescence parameters (Fo, Fm, Fv, Fv/Fm, Fm/Fo and t(1/2)), photopigments (Chl a, Chl b, Chl a+b, the Chl a/b ratio, and total carotenoids), as well as total phenolics (free and bound) in privet (Ligustrum ovalifolium Hassk.) in 'Stara Zvezdara' Park, located along the avenue with heavy traffic flow (polluted site), and the Arboretum of Belgrade's Faculty of Forestry (control site). Site-dependent variations were observed for all the parameters examined. It was found that Pb accumulated in leaf tissues (3.5-4.2microg/g) originates from traffic. Results obtained showed that privet is tolerant to the accumulation of Pb generated by traffic, because it maintains optimal photosynthesis and is characterized by active protection mechanisms due to increase in leaf phenolics, which enable it to survive in habitats exposed to chronic Pb pollution stress. Therefore, L. ovalifolium has great potential for urban landscaping.

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The floristic composition, the abundance, and the cover of pioneer plant species of spontaneously formed plant communities and the content of total phenolics and phenolic acids, as humus constituents, of an ash deposit after 7 years of recultivation were studied. The restoration of both the soil and the vegetation on the ash deposits of the "Nikola Tesla-A" thermoelectric power plant in Obrenovac (Serbia) is an extremely slow process. Unfavorable physical and chemical characteristics, the toxicity of fly ash, and extreme microclimatic conditions prevented the development of compact plant cover. The abundance and cover of plants increased from the central part of the deposit towards its edges (ranging from 1-80%). Festuca rubra L., Crepis setosa Hall., Erigeron canadensis L., Cirsium arvense (L.) Scop., Calamagrostis epigeios (L.) Roth., and Tamarix gallica L. were the most abundant species, thus giving the highest cover. Humus generated during the decomposition process of plant remains represents a completely new product absent in the ash as the starting material. The amount of total phenolics and phenolic acids (38.07-185.16 microg/g of total phenolics and 4.12-27.28 microg/g of phenolic acids) in fly ash increased from the center of the deposit towards its edges in correlation with the increase in plant abundance and cover. Ash samples contained high amounts of ferulic, vanillic, and p-coumaric acid, while the content of both p-hydroxybenzoic and syringic acid was relatively low. The presence of phenolic acids indicates the ongoing process of humus formation in the ash, in which the most abundant pioneer plants of spontaneously formed plant communities play the main role. Phenolic compounds can serve as reliable bioindicators in an assessment of the success of the recultivation process of thermoelectric power plants' ash deposits.

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A new concept in external skeletal fixation is presented. A 3D unilateral system developed by Mitkovic has widely been investigated biomechanically in AO institute in Davos (Switzerland). Consists of three components only providing extremely simple application and dynamic fixation of bones and different joints. This simple external fixator functions as an accurate reduction device at the same time, minimizing need for fluoroscopy. Clinically this system has been applied to mere then 13 thousand patients in 43 clinics. This paper presents the results of its application for treatment of open fractures, war wounds with fractures and for comminuted and intraarticular closed fractures in the series of 597 patients. Overall average time for union time was 3.2 months. Overall success of fracture healing was 96.8% including open and closed fractures. Our study suggests that the use of this 3D unilateral system is suitable for routine use.

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One of the main goals in fracture treatment is reservation of both intramedular and periosteal vascularisation. The aim of this paper is to show a new method of internal fixation which accomplishes these goals. The paper presents the results of clinical application of Mitkovic Internal Fixator, new self-dynamisable device, which provides fixation of the femur using minimally invasive technique. This device has been investigated experimentally on 60 animals. It has been applied to 267 patients. Here is presented a series of 92 fixations of femoral diaphyses after fresh fractures and after unsuccessful treatment using other methods. Follow-up was 3.1 years (2 to 7 years). Bone healing was achieved in all patients within 3.5 months (2.7-9 months) with big amount of periosteal callus formation. There were no complications in all patients seen. It can be concluded that this method and device meet biological and biomechanical requirements for safe fracture treatment.

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The results of limb lengthening, correction of limb deformities and solving of bone loss, by the use of Mitkovic external fixation system and minimally invasive technique on the series of 96 operations in 89 patients are shown. Only lower extremities were included in this series. The advantages of this external fixation system in comparison to other systems are pointed out. The main advantages are the optimal biomechanical conditions including unilateral but 3-dimensional frame, which provides conditions very similar to natural biomechanical features of the human long bones, simplicity of application and low cost. The received result was excellent or very good in 98.4%. Maximal limb lengthening was 18 cm (at the same time in the femur and the tibia). Angular deformity correction is extremely simplified with minimized possibility of complications. The frame for bone transport is very simple. It can be concluded that presented methods are suitable for routine use.

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The release of recombinant human bone morphogenetic protein-2 (rhBMP-2) from three room temperature polymerising methacrylate systems has been studied. These all contained poly(ethyl methacrylate) powder, but the monomer liquids comprised, respectively, tetrahydrofurfuryl methacrylate (THFM), 90/10 THFM/hydroxyethyl methacrylate (HEMA), and 70/30 THFM/ HEMA. In all cases, rhBMP-2 was released, but the addition of 10% HEMA accelerated release (a nine-fold increase in diffusion coefficient); a further increase to 30% HEMA had no additional effect. For most of the release process, a diffusion process operated, although the early stages were not well defined. At the end of the 15 day period, the release, respectively, for the PEM/THFM, PEM:90/10 THFM/HEMA and PEM:70/30 THFM/HEMA systems was 596, 878 and 923 ng (i.e. up to 92% of the rhBMP-2 added).

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Heart and brain vascular diseases are the leading causes of mortality in the world. Cardiac complications can frequently occur during the development of cerebral ischemia. The aim of this study was to establish the possible changes in fractions of creatinine-phosphokinase as the sensitive laboratory index of parenchymal lesion of brain parenchyma and the presence/absence of risk factors for ischemic brain and heart disease. The study comprised 80 patients with acute ischemic brain disease (AIBD), without the history of previous coronary disease. Blood samples were taken in all patients within the first 48 hours from AIBD onset aiming to determine a total (muscular MM) and heart fraction of creatinine-phosphokinase (MB), and brain parenchyma ischemia was confirmed by CT or MR scan of the head. A detailed history of the risk factors for ischemic brain disease (IBD) and ischemic heart disease was taken from all patients with AIBD, and the profile of glycemia and lipid status were determined, and blood pressure was measured 6 times a day. Independent variables in statistical analysis were: age, degree of severity and the side of neurologic event, size of ischemic lesion and maximal values of systolic and dyastolic pressure. Dependent variables were the values of fractions of creatinine-phosphokinase (CPK). Control group (n = 40) comprised patients with neurologic diseases of non-vascular origin. All parameters as well as their interrelations were statistically analyzed. The results revealed significant correlation of the increased levels of CPK of MM and MB fraction with the size and place of ischemic lesion in the right cerebral hemisphere, which was highly significant for MB fraction in the total group of patients with AIBD, and for MM fraction, only for cases of more severe IBD. Highly significant increased values of those fractions were also observed compared to the control group of patients.

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Thermal plasmas may solve one of the biggest toxic waste disposal problems. The disposal of polychlorinated biphenyls (PCBs) is a long standing problem which will get worse in the coming years, when 180000 tons of PCB-containing wastes are expected to accumulate in Europe (Hot ions break down toxic chemicals, New Scientist, 16 April 1987, p. 24.). The combustion of PCBs in ordinary incinerators (at temperature T approximately 1100 K, as measured near the inner wall of the combustion chamber (European Parliament and Council Directive on Incineration of Waste (COM/99/330), Europe energy, 543, Sept. 17, 1999, 1-23.)) can cause more problems than it solves, because highly toxic dioxins and dibenzofurans are formed if the combustion temperature is too low (T<1400 K). The paper presents a thermodynamic consideration and comparative analysis of PCB decomposition processes in air or argon (+oxygen) thermal plasmas.

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UNLABELLED: Prolonged QT dispersion which has been proposed as a marker of repolarisation inhomogeneity, may predispose to ventricular arrhythmias in a variety of cardiac disorders. The aim of this study was to compare some indices of QT dispersion in patients with heart failure compared to normal subjects. We have also tested the hypothesis that QT dispersion is a useful method for identifying the patients at high risk for ventricular arrhythmias. METHODS: There were 84 patients, divided into two groups. In the first group there were 62 patients with heart failure, in the sinus rhythm, while in second group there were 22 sex- and age-matched healthy subjects. Simultaneous 12-channel ECGs were recorded at a paper speed 50 mm/sec. Ventricular arrhythmias were quantified by 24-h Holter ECG and classified according to the Lown classification system. Only those patients with a class IVa, IVb, and V arrhythmia were considered to have complex ventricular premature contractions (PVCs). Measurements of QT, JT, and RR intervals were performed manually. Heart rate corrected QT and JT intervals (QTc and JTc) were calculated by Bazett's formula. RESULTS: RR intervals were similar in both groups (862 +/- 120 vs 840 +/- 86; ns). QT dispersion and rate corrected QT dispersion were significantly greater in heart failure patients than in controls (76 +/- 13 ms vs 37 +/- 11 ms and 89 +/- 21 ms vs 40 +/- 17 ms; p < 0.05). When, on the basis of the existing complex PVCs, heart failure patients were divided into two subgroups, QT dispersion and rate corrected QT dispersion were significantly greater in the subgroup with complex PVCs compared to patients without complex PVCs (84 +/- 14 ms vs 61 +/- 18 ms and 98 +/- 26 ms vs 66 +/- 21 ms; p < 0.05). CONCLUSION: All indices of QT dispersion were significantly higher in heart failure patients. QT dispersion is useful, noninvasive method for identifying heart failure patients at high risk for ventricular arrhythmia.

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UNLABELLED: The aim of the study was to examine if there existed a risk from interference of cellular phones on patients with implanted permanent pacemakers. The study comprised 144 patients (134 VVI/VVIR and 10 DDD/DDDR) with permanent pacemakers of different manufactures. METHODS: During the routine pacemaker check, cellular phone aerial (Nokia 1610; GSM Standard) was placed against the skin of patients above the spot of pacemaker implantation, while the phone calls were repeated and ECG was continuously monitored. The effect of cellular phone on pacemaker was established upon: a) preexisting parameters of electric pacemaker stimulation; b) minimal ventricular rate of 90 beats/min, while electric stimulation parameters were set to their most sensitive values (MSV). RESULTS: Only in 9 (6.25%) patients was observed intermittent pacemaker inhibition, when pacemaker settings were on preexisting values of electric stimulation, while in 17 patients (11.8%) inhibition was noticed, when pacemaker settings were changed to their MSV. Besides, programmed values of electric stimulation in our patients remained unchanged. CONCLUSION: Although the electromagnetic interference interactions of cellular phones on pacemaker function were observed in relatively small number of our patients, we were of the opinion that pacemaker-dependent patients should avoid the use of cellular phones.

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Pulsed Doppler echocardiographic and hemodynamic examinations were performed in 31 patients (mean age 17.8 years) with isolated ventricular septal defect (VSD). Three groups were studied: group I (n = 6) patients had severe pulmonary vascular obstructive disease (PVOD); group II (n = 12) patients had pulmonary hypertension (PH) without severe PVOD; group III (n = 13) patients had no PH. Bidirectional shunting was detected in 9 VSD patients (6 in group I and 3 in group II). Patients with low to moderately elevated right ventricular pressures demonstrated left-to-right shunting across the defect throughout the cardiac cycle. When systolic pressure in the right ventricle reached approximately 60% of the left ventricular pressure, right-to-left shunting occurred across the defect during early and mid diastole. However, in patients with Eisenmenger syndrome (group I) the right-to-left shunting occurred during late systole with continuation during the early and mid diastolic period. The earlier occurrence of right-to-left shunting (index < 0.5 second) signifies the presence of severe PVOD.

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In 13 patients with isolated mitral stenosis in sinus rhythm the pulmonary venous flow was evaluated by transoesophageal pulsed Doppler echocardiography. The patients were divided into two groups according to their mitral valve area (MVA); Group I (MVA < 1.5 cm2, n = 7 patients); and Group II (MVA > 1.5 cm2, n = 6). The patients in group I with haemodynamically significant mitral stenosis had lower velocities of systolic (S), diastolic (D) and atrial retrograde (A) waves of pulmonary venous flow (PVF) compared to milder stenosis (P < 0.05). The peak velocity of pulmonary retrograde venous flow at atrial contraction (A) primarily depends on the relative amplitude of the atrial transmitral wave (RA), which is measured from the onset of atrial systole to its peak velocity. We found a highly positive correlation between RA of mitral valve flow (MVF) and A wave of PVF (r = 0.87, P < 0.0001). There was also a highly negative correlation (r = 0.80, P < 0.001) between A of PVF and ratio of early (PE) to late (PA) velocities of MVF. Therefore, the retrograde A wave of PVF is related to the pressure generated in the left atrium during atrial systole. Use of pulmonary vein velocities in conjunction with mitral flow velocities can increase our understanding of the haemodynamics of mitral stenosis and provide a new insight into left atrial performance.

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From January 1986 through December 1990, we used pulsed Doppler echocardiography to evaluate left ventricular diastolic function in 43 patients with an ostium secundum atrial septal defect. The study population included 27 females and 16 males, whose ages ranged from 6 to 58 years (mean, 26 years). The patients were grouped according to degree of pulmonary hemodynamic impairment: patients in Group 1 (n = 6) had severe pulmonary hypertension, those in Group 2 (n = 10) had mild-to-moderate pulmonary hypertension, and those in Group 3 (n = 27) had no pulmonary hypertension. For comparison, we also evaluated 30 healthy individuals. All control subjects had a normal left ventricular filling profile. Of the 43 study patients, 8 (19%) showed Doppler echocardiographic signs of impaired left ventricular relaxation, including a prolonged left ventricular isovolumic relaxation time, decreased peak left ventricular diastolic inflow velocity, and a prolonged mean deceleration time of early diastolic flow velocity. Of these 8 patients, 5 were from Group 1, 1 was from Group 2, and 2 were from Group 3. A positive correlation (r = 0.66; standard error of the estimate = 0.32) was found between the late-to-early left ventricular diastolic inflow velocity ratio and the pulmonary-to-systemic vascular resistance ratio. Our results showed impaired left ventricular relaxation in 8 (19%) of patients with atrial septal defect; 5 of these patients had severe pulmonary hypertension. We therefore conclude that left ventricular diastolic dysfunction is closely related to severe pulmonary hypertension.

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