| 1. |
- Smolarz, Katarzyna, et al.
(författare)
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Argyrophilic nucleolar organizer regions (AgNORs) in interphases and metaphases of normal and neoplastic gill cells of Macoma balthica (Bivalvia: Tellinidae) from the Gulf of Gdansk, Baltic Sea
- 2003
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Ingår i: Diseases of Aquatic Organisms. - 0177-5103 .- 1616-1580. ; 56, s. 269-274
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Tidskriftsartikel (refereegranskat)abstract
- Chromosome analysis of gill cells of different populations of Macoma balthica (L.) from the Bay of Gdansk (Baltic Sea) revealed 2 clam categories, 1 with neoplastic features and 1 without. Silver-staining was performed on interphase and metaphase cells of both categories. The mean argyrophilic nucleolar organizer region (AgNOR) count per abnormal interphase cell was significantly higher than in normal interphase cells. Normal silver-stained metaphases had 3 nucleolar organizer region (NOR) chromosome phenotypes. The location of the NORs in the most frequent phenotype (55.6% in 54 metaphases scored) was interstitial on the largest metacentric chromosome pair, Pair No. 1. Abnormal silver-stained metaphases had a higher number of active NOR sites. Different phenotypes were observed (frequency greater than 10% for 67 metaphases scored); 2 were similar to those in normal metaphases and 5 were ectopic. The higher activity of AgNORs observed in abnormal cells confirmed the diagnosis of malignant neoplasia
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| 2. |
- Smolarz, Katarzyna, et al.
(författare)
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First record of the occurrence of ”Gill disease” in Mytilus edulis trossulus from the Gulf of Gdansk, Poland
- 2006
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Ingår i: Journal of Invertebrate Pathology. - : Elsevier BV. - 0022-2011 .- 1096-0805. ; 93:3, s. 207-209
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Tidskriftsartikel (refereegranskat)abstract
- We are presenting the first report of the occurrence of “gill disease” in Mytilus edulis trossulus from the southern Baltic Sea, Gulf of Gdańsk (Poland). The disease preliminary diagnosis was based on the presence of white and yellow “spots” causing deep indentations in the gills with degeneration, destruction and necrosis of gill filaments. Average prevalence of gill erosion in the blue mussels population was 15.8%. According to other authors, gill erosion may affect over 80% of the bivalve population resulting in mortality rates of up to 40%. The origin of the gill erosion remains unknown, but viruses are most likely involved in the etiology of these pathological conditions. The disease as such may indicate a decrease in the immunological resistance of organisms to infections and inflammations directly or indirectly caused by harmful factors in the ambient environment. Furthermore, the occurrence of numerous pathologies in bivalves is a particular problem in the Gulf of Gdańsk being a low biodiversity ecosystem. Pathologies reduce bilvalves’ reproduction ability, worsen their physiological condition and increase their mortality rate. Those factors may also pose a significant ecological danger and lead to negative alterations of the ecosystem.
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| 3. |
- Smolarz, Katarzyna, et al.
(författare)
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Histology, cytogenetics and cytofluorymetry in diagnosis of neoplasia in the Baltic clam Macoma balthica (Bivalvia, L.) from the Gulf of Gdansk (Baltic Sea)”.
- 2005
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Ingår i: Caryologia (Firenze). - 0008-7114 .- 2165-5391. ; 58:3, s. 212-219
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Tidskriftsartikel (refereegranskat)abstract
- This study presents results of histopathologic, cytogenetics and flow cytometry analyses performed on Macoma balthica collected from the Gulf of Gdansk (Baltic Sea) in 2003 in order to compare the techniques for diagnosis of neoplasia. The proportion of affected clams gave a crude prevalence of 15.7 %. The four stages of the disease defined by histology and three stages of neoplasia defined by flow cytometry were reported. Stage I defined by flow cytometry corresponded to stages I and II defined by histology. Chromosome analysis did not lead to a staging of neoplastic progression. Both cytogenetics and flow cytometry indicated a difference in the DNA content of non-neoplastic and neoplastic cells. Cytogenetics examination marked that the range of chromosome numbers scored in abnormal mitosis corresponded to pentaploid-like cells (2.37 x diploid) and was similar to the mean DNA quantity identified using flow cytometry (2.36 x diploid). These methods generally have lower diagnosis sensitivity because with both techniques only a part of an animal can be studied. Thus, histology examination appeared to be the most sensitive tool for detection of the possible foci of neoplastic cells, metastasis and rare tumour cells freely circulating in the hemolymph in the early stages of the disease. Cytogenetic analysis has been considered as an important tool for the evaluation of aquatic environment quality as well as for the ecological risk assessment. Flow cytometry provided a rapid and easy method for discrimination of the aneuploid cells within thousands of cells per individual. Thus, in diagnosis of early stages of the cancer as well as early metastasis histology analyses should be performed. Chromosomes analysis and flow cytometry examination are important techniques for detection abnormalities in cell division, cell viability and DNA quantity. They appear to be very important in diagnosis of tumors based on high aneuploidy level
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| 4. |
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| 5. |
- Smolarz, Katarzyna, et al.
(författare)
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Recent trends in prevalence of neoplasia in the Baltic clam Macoma balthica (L.) from the Gulf of Gdansk (Baltic Sea)
- 2005
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Ingår i: Oceanologia. - 0078-3234. ; 47:1, s. 61-74
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Tidskriftsartikel (refereegranskat)abstract
- This study discusses the occurrence of neoplasia in the Baltic clam Macoma balthica from the Gulf of Gdańsk in recent years and investigates potential relationships between toxic compounds in the environment and the presence of the cancer. The disease was identified at four sampling stations during 1999-2002. Comparison with previous results highlighted the substantial prevalence of the tumour between 1998 and 2002. The prevalence of the cancer was strongly dependent on the sampling location (p > 0.001): it was highest at sampling point H45 (the deepest part of the gulf) and lowest at station PB30 (central part of the gulf). Monthly studies showed a trend towards an increasing prevalence of neoplasia during the warm months. However, over several sampling months no strong statistical correlation between the prevalence of the disease and the sampling time was found. The results of the study suggest that several environmental factors may promote the progress of the cancer in M. balthica from the Gulf of Gdańsk: it is most probably an indirect effect of pollution, although causality cannot be proven at this stage. Seriously polluted and exhibiting a considerable asymmetry of contamination, the ecosystem of the gulf provides an ideal environment for testing potential cause-effect relationships between pollutants and their biological effects
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| 6. |
- Smolarz, Katarzyna, et al.
(författare)
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Ultrastructural study of neoplastic cells in Macoma balthica (Bivalvia) from the Gulf of Gdansk (Poland)
- 2006
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Ingår i: Journal of Invertebrate Pathology. - : Elsevier BV. - 0022-2011 .- 1096-0805. ; 92:2, s. 79-84
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Tidskriftsartikel (refereegranskat)abstract
- In the Baltic clam Macoma balthica from the Gulf of Gdansk, neoplasia is considered as a serious epizootic linked to bad environmental conditions and high levels of pollutants. Previous research was focused on the diagnosis, prevalence, seasonality and histopathological characteristic of the cancer. This study is focused on electron microscopy analyses describing cell ultrastructure abnormalities related to neoplasia. Examinations using the electron microscopy highlighted changes confined to anatomic ultrastructures, shapes and functions of neoplastic cells. The lobulated appearance of the nucleus, changes in cellular matrix and the occurrence of large granular cells with hyperchromatic nuclei, atypical Golgi structures and deterioration of rough endoplasmic reticulum manifested the disease. The presence of atypical mitochondria, free ribosomes and hypertrophic nuclei suggests the adaptation of neoplastic cells to increased mitotic activity, while the observed modification of cellular membranes may reflect functional changes connected to increased pinocytotic activity or intercellular transport. The cancer cells were found to appear in two types, abnormal round-shaped cells and spindle-shaped cells, both with increased frequencies of cell division. Round-shaped cells typical for disseminated neoplasia were observed in all affected bivalves, in a few cases co-occurring with abnormal spherical cells. Spindle-shaped cells containing some intracytoplasmic filaments, and with a tendency of the nuclei to be orientated as in a palisade were interpreted as myofibroblasts-like cells and were observed in five out of eleven clams diagnosed as neoplastic. This finding represents the first demonstration of phenotypic differences in the cell types co-occurring in animals diagnosed as neoplastic and by that suggests coexistence of two types of bivalve cancer, disseminated neoplasia and probable fibrosarcoma.
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| 7. |
- Sokolowski, Adam, et al.
(författare)
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Abnormal features of M. balthica (Bivalvia) in the Baltic Sea : alerting symptom of environmental changes?
- 2004
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Ingår i: Marine Pollution Bulletin. - : Elsevier. - 0025-326X .- 1879-3363. ; 49:1-2, s. 17-22
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Tidskriftsartikel (refereegranskat)abstract
- Recent studies of the Baltic clam Macoma balthica (L.) from the southern Baltic (the Gulf of Gdansk) have revealed striking morphological, histological and cytogenetic features. Strong deformation of the shell, including elongation of the posterior end and the appearance of an easily visible flexure in this part, has been recorded. The population contribution of the deformed blunt shelled (“irregular”) clams ranged from 0% to 65% and tended to increase with depth. The morphologically “irregular” clams had higher accumulated tissue concentrations of trace metals (As, Ag, Cd, Pb, Cu and Zn), indicating a different metal handling ability. Adverse conditions in deeper water regions of the Gulf (e.g. hypoxia, hydrogen sulphide, elevated bioavailability of contaminants) have been suggested as inducers of the phenotypical changes (morphological deformation) in part of the population and, in parallel, of the specific physiological adaptations that result in higher metal accumulation in the “irregular” clams. Cytogenetic and histological analyses showed the presence of tumours in gill cells and digestive system of the affected clams, the prevalence of disseminated neoplasia ranging from 0% to 94% depending on the site. The disease was manifested by a modified karyotype (i.e. an abnormal number and morphology of chromosomes), a higher activity of nucleolar organizer regions (AgNORs), and tissue lesions (enlarged cells, actively proliferative with pleomorphic nuclei). Bottom sediments showed acute toxicity and have been proposed as a source of an initialising carcinogenic factor. However, none of the ecotoxicological studies provided was successful in the clear demonstration of a single (or multifactorial) agent that can account for the disseminated neoplasia.
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| 8. |
- Tomaszkiewicz, Marta, et al.
(författare)
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Heterogamety in the Baltic Glacial Relict Saduria entomon (Isopoda: Valvifera)
- 2010
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Ingår i: Journal of Crustacean Biology. - : Oxford University Press (OUP). - 0278-0372 .- 1937-240X. ; 30:4, s. 757-761
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Tidskriftsartikel (refereegranskat)abstract
- This study describes the karyology of an isopod, Saduria entomon, and provides for the first time evidence of a XY/XX heterogamety for this species. The presented karyotype [56 (m + sm ) + 2 st + XX/XY] is characterised by the dominance of metacentric and submetacentric chromosomes and is considered as apomorphic. This is the first time a valviferan is described with an XX/XY system. Mitotic and meiotic heterogamety observed in S. entomon suggests more advanced evolution of sex determination within this species in comparison to other Isopoda. Based on Ag-staining the presence of secondary constrictions and satellites on the 22nd pair of homologous chromosomes was identified. Inter- and intra-individual variability in chromosome number (2n = 58, 2n = 59 or 2n = 61) was also observed. The between-species variation in heterogamety in isopods and the within-species variation in chromosomes numbers are discussed
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| 9. |
- Wolowicz, Maciej, et al.
(författare)
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Neoplasia in estuarine bivalves. Effect of feeding behaviour and pollution in the Gulf of Gdansk (Baltic Sea, Poland)
- 2005
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Ingår i: The Comparative Roles of Suspension-Feeders in Ecosystems. - Dordrecht : Springer. - 9781402030307 ; , s. 165-182
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Bokkapitel (refereegranskat)abstract
- The incidence of tumors in bivalve molluscs is receiving increased attention due to possible detrimental effects on harvested stocks. Although the etiology or causes of neoplasias remains unclear, pollution by carcinogenic agents is implicated in the heavily exploited littoral zones of coastal waters. In the Gulf of Gdańsk, southern Baltic Sea, a higher prevalence of the disorder was observed in infaunal facultative (deposit/suspension) feeders compared to epifaunal obligate suspension-feeders, providing a new behavioural aspect of the tumor. Recent studies also reveal a potential cause-and-effect relationship between sediment factors and the incidence of neoplasia across a range of environmental properties
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