21 research outputs found

    The phylosophy and applicability of ecoremediations for the protection of water ecosystems

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    The problem of accelerated eutrophication of the water ecosystems has not been appreciated proportionally to the development of human society today. Accelerated or fast eutrophication is detected destiny in majority of ecosystems today, mainly due to adverse human impact. This paper aims to introduce ERM methods in treating the problems arising from increased total capacity and saprobity and also accelerated eutrophication. In this way the broadness and importance of ERM as an ecosystem service for the water protection should be emphasized. The basic characteristics of ERM are its high buffer and self-protective capacities, and preservation of natural habitats and biological diversity. ERM represents the ‘returning to nature’ approach aiming to preserve or re-establish the natural balance of the ecosystems, but also a human endeavor that enables new jobs and by-side activities important for economic and social development of the human society

    Freshwater Cyanobacterial blooms and Cyanotoxin production in Serbia in the past 25 years

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    Since 1980 cyanobacterial blooms occurred in a large number of reservoirs lakes and water flows (rivers and channels) in Serbia. Among 83 water ecosystems examined, 58 were found in blooming condition almost every year during last 2 decades. All natural lakes, accumulations, rivers and canals in Vojvodina province (agricultural part) proved to be sites with frequent cyanobacterial proliferation. During the summer 2005-spring 2006 microcystin-LR survey in Vojvodina, the toxin was permanently present in all examined ecosystems and the highest value of 362.68 μgL-1 was detected in Ludoš Lake. The part of Central Serbia is very problematic for ground water supply. For that reason more than 20 reservoirs serve as drinking water suppliers. Significant and persistent cyanobacterial blooms have been recognized in 9 of them. Samples for cyanotoxin analyses were taken during and after blooms in Ćelije Reservoir and in drinking water in Kruševac town 2 days later. Concentration of microcystin-LR was 650 μgL-1 in the reservoir while the tap water contained 2.5μgL-1

    Observations of the genus muelleria (bacillariophyceae) from the Republic of north Macedonia

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    Background and aims – An increased interest in the diatom flora from subaerial habitats in the Republic of North Macedonia has revealed the presence of a large number of interesting and often unknown, species. During a recent biodiversity survey, seven Muelleria species were recorded, several of which could not be identified based on the available literature. Methods – Using both Light Microscopy and Scanning Electron Microscopy techniques, the morphology of several Muelleria species has been analysed. The morphology of all taxa is described, illustrated and compared with other possible similar Muelleria taxa, known worldwide. Key results – Four already documented Muelleria species, M. gibbula, M. islandica, M. terrestris and M. undulata (= Navicula gibbula f. undulata) were identified, while two distinct species are described as new. These new species belong to the M. gibbula complex, and can be differentiated by valve size, stria density, shape of the proximal raphe ends and the shape of external areola foramina. The identity of one taxon remains uncertain due to a low number of observed specimens in the samples. As their ultrastructure is almost entirely unknown, they are briefly discussed. Conclusions – The diversity of Muelleria in Europe and the North Hemisphere is most likely underestimated and some of the previous records of M. gibbula belong to other species. Observations of diatoms from “extreme” habitats such as intermittent ponds, wet mosses and soils can reveal the existence of interesting and new species

    Temperature Effects Explain Continental Scale Distribution of Cyanobacterial Toxins

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    Insight into how environmental change determines the production and distribution of cyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus on hepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g., anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to their potency. Most studies examine the relationship between individual toxin variants and environmental factors, such as nutrients, temperature and light. In summer 2015, we collected samples across Europe to investigate the effect of nutrient and temperature gradients on the variability of toxin production at a continental scale. Direct and indirect effects of temperature were the main drivers of the spatial distribution in the toxins produced by the cyanobacterial community, the toxin concentrations and toxin quota. Generalized linear models showed that a Toxin Diversity Index (TDI) increased with latitude, while it decreased with water stability. Increases in TDI were explained through a significant increase in toxin variants such as MC-YR, anatoxin and cylindrospermopsin, accompanied by a decreasing presence of MC-LR. While global warming continues, the direct and indirect effects of increased lake temperatures will drive changes in the distribution of cyanobacterial toxins in Europe, potentially promoting selection of a few highly toxic species or strains.Peer reviewe

    Dominance of Microcystis spp. in Lake Dojran – a consequence of 30 years of accelerated eutrophication

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    In the past 30 years, Lake Dojran (Macedonia) has experienced extreme periods of droughts and water removal for irrigation purposes that have resulted in an accelerated process of eutrophication leading to hypertrophy. In the present paper, we document successive changes of the microflora in plankton communities as a result of the prolonged eutrophication impact over this period. The original well established phytoplankton community in the lake, which was rich in species (especially coccoid green forms belonging to the genera Pediastrum, Scenedesmus, Staurastrum and Tetraedon) and which followed the natural annual succession in the form of diatoms > green algae > cyanobacteria, has been greatly modified over the years. Two episodes of intensive ‘water blooms’ have been recorded, one involving Gloeotrichia natans (in 1993/94) and the other the dinoflagellates Ceratium hirudinella and C. monoceros (1996/97), events that indicated drastic changes of the ecological conditions. Dominance of Dolichospermum aff. flosaquae was recorded in 2008. Finally, the phytoplankton in Lake Dojran completed a turnover towards the overall dominance of Microcystis spp., with a total of nine co-existing species. The first documented record of Microcystis protocystis outside pan- and neotropical regions is here presented. The described successions in phytoplankton species composition and dominance are attributed to gradual and constant changes in the nutrient status of the lake in the direction of hypertrophy, the basic nutritive parameters, total P and N content, having increased more than 40- and eight-fold, respectively, over the years. Measurements of cyanobacterial toxicity have been few, and they were sporadically performed. Nonetheless, the presence of microcystins in the water has been documented, with indications of significant concentration peaks. The paper is intended to be a tribute to all scientific workers who, like Professors Jelena and Živojin Blaženčić, have devoted their expertise and time to the task of revealing forced changes in the lake’s biota in the hope of creating a favourable atmosphere for immediate human intervention to save this once very rich and diverse ecosystem

    The phylosophy and applicability of ecoremediations for the protection of water ecosystems

    Get PDF
    The problem of accelerated eutrophication of the water ecosystems has not been appreciated proportionally to the development of human society today. Accelerated or fast eutrophication is detected destiny in majority of ecosystems today, mainly due to adverse human impact. This paper aims to introduce ERM methods in treating the problems arising from increased total capacity and saprobity and also accelerated eutrophication. In this way the broadness and importance of ERM as an ecosystem service for the water protection should be emphasized. The basic characteristics of ERM are its high buffer and self-protective capacities, and preservation of natural habitats and biological diversity. ERM represents the ‘returning to nature’ approach aiming to preserve or re-establish the natural balance of the ecosystems, but also a human endeavor that enables new jobs and by-side activities important for economic and social development of the human society

    Synchronous mantle cell lymphoma and prostate adenocarcinoma-is it just a coincidence?

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    Introduction. Synchronous occurrence of lymphomas and other cancers, mostly carcinomas are well established. The most of cases describe chronic lymphocytic leukemia as the leading lymphoproliferative disease with the tendency towards secondary malignancies development. Mantle cell lymphoma (MCL) has been described in only 2 cases to co-occur with prostate adenocarcinoma (PAC). There are scarce data about the connection between MCL and urology cancers. We presented the first case of synchronous occurrence of MCL and PAC in the same patient in Serbia. Case report. A 64-year-old male initially presented with fatigue, splenomegaly, and bicytopenia. The bone marrow biopsy specimen revealed extensive infiltration with MCL. During lymphoma staging procedure prostate enlargement (57 mm) was accidentally found by multislice- computed tomography (MSCT). The serum prostate specific antigen (PSA) was elevated (52 ng/mL; normal values ≤ 4 ng/mL). Transrectal ultrasound biopsy revealed PAC. High Gleason score determined high-risk locally advanced PAC. The patient underwent treatment with chemotherapy and hormone therapy due to the existence of double malignancies. Cyclophosphamide, doxorubicin, vincristine, prednisone (CHOP) was applied for MCL, and luteinizing hormonereleasing hormone (LHRH) agonist, triptorelin, for PAC. Partial response was obtained for MCL, and stable disease for PAC. In a 1.5-year observation period the patient was still disease progression free for both of malignancies. Conclusion. This case points aut that elderly males are in need for careful observation during the staging procedure for lymphoma. The literature data suggest that MCL patients are in increased risk for urologic malignancies development. However, the etiologic connection between these two entities, except male gender and older age, remains unclear
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