The diversity and longitudinal changes of zooplankton in the lower course of a large, regulated European river (the lower Vistula River, Poland)

The diversity and longitudinal variation of zooplankton in the lower Vistula River were analyzed. Samples were taken from 40 stations located along a 272-km long section of the lower river course. During the study the unique technique of taking samples from “the same water” was used. The zooplankton community was dominated by rotifers and nauplii — larval stages of copepods. The most abundant species were: Brachionus angularis, Brachionus calyciflorus and Brachionus budapestiensis. The zooplankton species diversity in the main channel of the lower Vistula River was similar to other large European rivers; however, its abundance was lower. The diversity, abundance and biomass of potamoplankton steadily decreased downstream. This could be related both to scarcity of storage zones for potamoplankton development in the river due to the extensive regulation processes, and changes in hydrological conditions of the main channel (by the straightening of riverbed) where the samples were collected.     

Length adjustment of larval and early‐juvenile cod (Gadus morhua) after up to 3 years of preservation in alcohol

Comparison of live Baltic cod larvae lengths and early‐juveniles with corresponding lengths after preservation in 95% ethyl alcohol for periods of one to 3 years resulted in an average shrinkage of 0.70 mm for the entire size range of 4–40 mm standard length cod. Although the relative shrinkage depended on fish size and varied from 2 to 20% of the fresh length, the absolute shrinkage values were not size dependent and did not change during the observed preservation period. Thus a general additive correction value of +0.7 mm can be used to calculate live lengths from measured standard lengths of alcohol‐preserved material.     

Distribution,abundance and condition of invasive Ponto‐Caspian gobies Ponticola kessleri (Günther, 1861), Neogobius fluviatilis (Pallas, 1814), and Neogobius melanostomus (Pallas, 1814) in the Sava River basin,Croatia

Distributions, population densities, invasive potentials and adverse impacts of invasive Ponto‐Caspian gobies on native fauna in the Sava River basin remain unknown, whereby 23 locations in the Sava basin were sampled during a three‐year period (2011–2013). Among the five Ponto‐Caspian goby species previously reported in Croatia, only Neogobius fluviatilis (291), Neogobius melanostomus (177) and Ponticola kessleri (21) specimens were collected. Proterorhinus semilunaris and Babka gymnotrachelus were not found. N. fluviatilis was dominant among the invasive gobies at the majority of locations and almost omnipresent (apart from the upper Sava reaches) in the Sava basin. N. melanostomus was found only in the navigable Sava reaches, but its distribution range still seems to be expanding. The status of P. kessleri invasion remains unclear, as it was only found in 2011 at three locations in the lower Sava reaches. No significant (P > 0.05) increase in average catch‐per‐unit‐effort (CPUE) values was observed during the three‐year period. There is some evidence that a decline in Gobio gobio populations might be expected in response to increasing N. fluviatilis population densities. The findings suggest that further range expansions by the Ponto‐Caspian gobies can be expected in Croatia and the implementation of measures to limit their spreading should be considered.     

A new cardiid bivalve from the Pliocene Baklan Basin (Turkey) and the origin of modern Ponto‐Caspian taxa

Abstract: We present the first record of the cardiid genus Monodacna from the Pliocene of Anatolia, Turkey. Monodacna imrei sp. nov. was found in the Pliocene Killik Formation from the western margin of the Baklan Basin, in very marginal brackish to freshwater lacustrine deposits. The new record extends the stratigraphic range of the modern Ponto‐Caspian genus back into the Pliocene and adds to earlier evidence that modern Ponto‐Caspian taxa originated in the Pliocene of south‐western Turkey.     

Reproductive biology of racer goby Neogobius gymnotrachelus in the Włocławski Reservoir (Vistula River, Poland)

Initial studies on the reproductive parameters and spawning behaviour of racer goby Neogobius gymnotrachelus, one of three Ponto‐Caspian gobiid species recently invading Polish waters, were carried out in W?oc?awski Reservoir (lower River Vistula, Poland), where spawning lasted from April to August. Males were on average about 23.3% longer and 53.8% heavier than females. The smallest female with mature gonads was 58 mm TL (estimated age 2+ years), and males were sexually mature at 59 mm TL (age of 1+ years). Gonado‐somatic index at the beginning of spawning was seven times larger in females (mean = 8.4) than that in males (mean = 1.2). Mean absolute fecundity was 952 eggs per female (361–2236). Egg diameter ranged from 0.140 to 1.558 mm, being of bi‐modal distribution, which suggests two or three spawning bouts. Length–frequency analysis of juveniles revealed a multimodal distribution. Specialized reproductive behaviour (nest construction and parental care of eggs) and an extended spawning period increase the probability that racer goby can successfully establish self‐sustaining populations in novel environments.     

Diet partitioning in summer of two syntopic neogobiids from two different habitats of the lower Vistula River, Poland

Monkey goby Neogobius fluviatilis and racer goby N. gymnotrachelus, both native to the Ponto‐Caspian region, were discovered in Polish rivers during the mid‐1990s and currently they are invading the River Vistula. Preliminary studies were carried out on the diet of both species at two sites in the lower River Vistula, one lotic (main channel of the river downstream of the W?oc?awek river reservoir) and the other lentic (left bank, middle section of the W?oc?awek Reservoir). Significant differences were noted in diet between the two species and within species according to habitat, in particular the types of chironomid taxa taken. Over a single diel cycle, monkey goby were captured between 07:00 and 19:00 hours only, feeding more intensively on chironomid larvae than the racer goby, which was captured at most times of day. The wide diet plasticity of these non‐native fish species favours their expansion.     

Possible antagonism of (Z)‐2‐hexenyl (E)‐3‐hexenoate against the attractiveness of (E)‐2‐hexenyl (Z)‐3‐hexenoate to Ooencyrtus nezarae (Hymenoptera: Encyrtidae)

Ooencyrtus nezarae (Hymenoptera: Encyrtidae) is an egg parasitoid of bean bug Riptortus pedestris (Hemiptera: Alydidae) which is a major pest of beans. Females of O. nezarae are attracted to (E)‐2‐hexenyl (Z)‐3‐hexenoate (EZ), one of the components of aggregation pheromone of R. pedestris. Effects of three isomers (ZE, EE and ZZ) of EZ on the attractiveness of O. nezarae were tested using electroantennography (EAG) and field bioassays. EAG analyses revealed that the response of O. nezarae to ZE was significantly higher than those to air, hexane and two other isomers, even though the response was lower than that to EZ. ZE affected the attractiveness of EZ dose‐dependently in the field. Addition of ZE (100 mg) to EZ (10 mg) caused a significant reduction in the catches of O. nezarae females. Single or binary addition of two other isomers (EE and ZZ) to EZ could not decrease or increase significantly the number of O. nezarae catches of EZ. Even though addition of ZZ (10, 50 or 100 mg) to EZ (10 mg) caused dose‐dependent reduction in the number of O. nezarae female catches, the reductions were not significantly different from that of EZ. EZ and its three isomers were not attractive to O. nezarae males at all.     

Molecular markers for systematic identification and population genetics of the invasive Ponto‐Caspian freshwater gammarid Dikerogammarus villosus (Crustacea,Amphipoda)

The Ponto‐Caspian amphipod, Dikerogammarus villosus, is an invasive species of many European rivers. First, we show that size difference of nrDNA ITS1 allows discriminating D. villosus from Dikerogammarus bispinosus, a closely related but morphologically hardly distinguishable species. Second, we present two types of polymorphic markers for D. villosus, three microsatellites and two single nucleotide polymorphisms (SNPs) of mtDNA COI gene, which were scored by polymerase chain reaction‐single strand conformational polymorphism (PCR‐SSCP). These markers will be very useful in studying population genetics of D. villosus.     

Review of negative and low‐grade cervical smears in women with invasive cervical cancer after the first 3 years of the national cervical screening programme in Slovenia

A. Repše‐Fokter, A. Pogačnik, V. Snoj, M. Primic‐Žakelj and M. S. Fležar
Review of negative and low‐grade cervical smears in women with invasive cervical cancer after the first 3 years of the national cervical screening programme in Slovenia Objective: The purpose of the study was to perform a national review of negative, low‐grade and inadequate smears reported during the latest screening period before cervical cancer diagnosis in 2006, after the first 3 years of the screening programme. Methods: Among 162 new cervical cancer cases there were 47 (29%) without previous cytology, 47 (29%) with one high‐grade smear prior to diagnosis and 68 (42.0%) with at least one previous negative, low‐grade, atypical or inadequate smear 1–40 months before diagnosis. Of the latter 68 cases, 37 patients with 59 smears (together with 118 control slides) were included in the review as 31 had smears reported at laboratories no longer operating. Findings were related to the last cytology report before diagnosis as well as to histological type and stage of the cancer. Results: In our study group, 19 (51%) of 37 patients had squamous cell carcinoma, 15 (41%) adenocarcinoma and 3 (8%) adenosquamous carcinoma, compared with 121 (75%), 26 (16%), 12 (7%), respectively, and 3 (2%) other types, for all carcinomas. Twenty‐one of 37 women also had high‐grade cytology prior to diagnosis of cancer. Women with previous cytology (with or without recent high‐grade smears) were more likely to have stage I cancers than those without cytology (P < 0.0001). The expert group upgraded 17/33 smears in the patients with squamous carcinomas, which was more than in those with adeno‐ and adenosquamous carcinomas (5/24, P < 0.05). Conclusion: As expected, a higher proportion of smears preceding adenocarcinomas were true negative. Under‐diagnosed smears were not related to cancer stage or last cytology report before diagnosis.     

Diurnal behavioural patterns and spread of the Ponto‐Caspian invader Hemimysis anomala G. O. Sars, 1907 (Crustacea,Mysidacea) in the Elbe River,Czech Republic

The Ponto‐Caspian invader Hemimysis anomala was studied in the river Elbe, Czech Republic. The study confirmed further spread of the species: the presence of juveniles and gravid females indicated that H. anomala is established within the Elbe River. Bottom, mid‐water and surface drift samples were collected during 24‐h cycles from July to September 2007. A tendency to remain hidden was the main behavioural strategy of H. anomala in the riverine environment. The mysid was found mainly in the bottom and mid‐water layers, and observed density and mean length of drifting individuals increased with decreasing light levels, being highest at night. Similarly, density and mean length of drifting individuals increased with increasing turbidity. The effect of turbidity on density was particularly apparent during the night samples, suggesting further advantage to night‐drifting individuals. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Over‐expression of bacterial γ‐glutamylcysteine synthetase (GSH1) in plastids affects photosynthesis,growth and sulphur metabolism in poplar (Populus tremula × Populus alba) dependent on the resulting γ‐glutamylcysteine and glutathione levels

We compared three transgenic poplar lines over‐expressing the bacterial γ‐glutamylcysteine synthetase (GSH1) targeted to plastids. Lines Lggs6 and Lggs12 have two copies, while line Lggs20 has three copies of the transgene. The three lines differ in their expression levels of the transgene and in the accumulation of γ‐glutamylcysteine (γ‐EC) and glutathione (GSH) in leaves, roots and phloem exudates. The lowest transgene expression level was observed in line Lggs6 which showed an increased growth, an enhanced rate of photosynthesis and a decreased excitation pressure (1‐qP). The latter typically represents a lower reduction state of the plastoquinone pool, and thereby facilitates electron flow along the electron transport chain. Line Lggs12 showed the highest transgene expression level, highest γ‐EC accumulation in leaves and highest GSH enrichment in phloem exudates and roots. This line also exhibited a reduced growth, and after a prolonged growth of 4.5 months, symptoms of leaf injury. Decreased maximum quantum yield (F_v/F_m) indicated down‐regulation of photosystem II reaction centre (PSII RC), which correlates with decreased PSII RC protein D1 (PsbA) and diminished light‐harvesting complex (Lhcb1). Potential effects of changes in chloroplastic and cytosolic GSH contents on photosynthesis, growth and the whole‐plant sulphur nutrition are discussed for each line.     

Species Composition and Distribution of Invasive Ponto‐Caspian Amphipods in the Off‐Channel Microhabitats of a Temperate,Lowland Dam Reservoir

The Włocławek Dam Reservoir located on the lower Vistula River (central Poland) is part of the central corridor used by Ponto‐Caspian species to migrate in Europe. It provides a number of habitats suitable for sustaining populations of several non‐indigenous taxa. Four Ponto‐Caspian amphipod species were recorded in the reservoir: Chaetogammarus ischnus, Chelicorophium curvispinum, Dikerogammarus haemobaphes and Pontogammarus robustoides. We found significant differences in amphipod densities and species composition among various microhabitats in off‐channel areas. P. robustoides was the only amphipod species that occurred on very shallow (<1 m) sandy bottom near the shore. It inhabited also other sites but its share in the total number of amphipods and abundance decreased with the distance from the shore. Furthermore, at sites more distant from shore its affinity for plant substratum was higher. D. haemobaphes, C. ischnus and C. curvispinum clearly preferred sites distant from shore, overgrown by macrophytes or covered by mussel shells. Furthermore, the abundance of C. ischnus was negatively correlated with the presence of P. robustoides. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Synthesis and Antioxidant Activity of 3‐(Pyridin‐2‐ylmethyl)‐1,3‐thiazinan(thiazolidin)‐4‐ones

The antioxidant properties of two series of thiazolidinones and thiazinanones were reported. The novel six‐membered thiazinanones were synthesized from the efficient multicomponent reaction of 2‐picolylamine (2‐aminomethylpyridine), arenaldehydes, and the 3‐mercaptopropionic acid in moderate to excellent yields. These novel compounds were fully identified and characterized by NMR and GC‐MS techniques. In vitro antioxidant activities of all compounds were evaluated by 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) and 2,2′‐azinobis‐3‐ethylbenzothiazoline‐6‐sulfonic acid (ABTS) tests. The antioxidant assays of thiobarbituric acid reactive species and total thiol content levels in the cerebral cortex and liver of rats were also performed. Thiazinanone 5a showed the best radical scavenging activity in DPPH and ABTS tests, as well as reduced lipid peroxidation and increased total thiol group in biological systems. Altogether, the results may be considered a good starting point for the discovery of a new radical scavenger.     

Design,Synthesis and Bioevaluation of Two Series of 3‐[(1‐Benzyl‐1H‐1,2,3‐triazol‐4‐yl)methyl]quinazolin‐4(3H)‐ones and N‐(1‐Benzylpiperidin‐4‐yl)quinazolin‐4‐amines

Two series of 3‐[(1‐benzyl‐1H‐1,2,3‐triazol‐4‐yl)methyl]quinazolin‐4(3H)‐ones and N‐(1‐benzylpiperidin‐4‐yl)quinazolin‐4‐amines were designed initially as potential acetylcholine esterase inhibitors. Biological evaluation demonstrated that N‐(1‐benzylpiperidin‐4‐yl)quinazolin‐4‐amines significantly inhibited AChE activity. Especially, two compounds of them were found to be the most potent with relative AChE inhibition percentages of 87 % in comparison to donepezil. The docking studies with AChE showed similar interactions between donepezil and four derivatives. N‐(1‐Benzylpiperidin‐4‐yl)quinazolin‐4‐amines also exhibited significant DPPH scavenging effects. The two series of compound also exerted moderate to good cytotoxicity against three human cancer cell lines, including SW620 (human colon cancer), PC‐3 (prostate cancer), and NCI?H23 (lung cancer), with 3‐[(1‐benzyl‐1H‐1,2,3‐triazol‐4‐yl)methyl]quinazolin‐4(3H)‐one being the most cytotoxic agent. 3‐[(1‐Benzyl‐1H‐1,2,3‐triazol‐4‐yl)methyl]quinazolin‐4(3H)‐one significantly induced early apoptosis and arrested the SW620 cells at G2/M phase. From this study, two compounds of N‐(1‐benzylpiperidin‐4‐yl)quinazolin‐4‐amines could serve as new leads for further design and AChE inhibitors, while 3‐[(1‐benzyl‐1H‐1,2,3‐triazol‐4‐yl)methyl]quinazolin‐4(3H)‐one could serve as a new lead for the design and development of more potent anticancer agents.     

Non-selective predator – the versatile diet of Amur sleeper (Perccottus glenii Dybowski, 1877) in the Vistula River (Poland), a newly invaded ecosystem

The Amur sleeper diet spectrum was investigated in addition to its spatial, seasonal and size-related changes, in order to predict which groups of native prey would be most affected by this exotic predator that has rapidly invaded many Eastern and Central European inland waters in recent decades. In total, 527 Perccottus glenii individuals were collected in four sites in the Włocławski Reservoir (the Vistula River, Baltic basin, Poland). Altogether 50 food categories were identified, including crustaceans, insects, molluscs, annelids, araneids, fishes and amphibians. Most of them were associated with aquatic vegetation, indicating that the Amur sleeper collects its prey from the submerged plants rather than directly from the bottom sediments. Amphipods and chironomid larvae, supplemented by zygopteran larvae and molluscs, composed the main forage base in all studied sites, although their importance was varied. The diet composition differed among P. glenii size-groups. Significant variation was found in numeric abundance of amphipods, chironomid larvae, fish and zygopteran larvae (Kruskal–Wallis P < 0.01). Seasonal changes in the diet were also observed whereby in spring and summer, dipteran larvae and amphipods were prevalent food items; the importance of molluscs and zygopteran larvae increased considerably in September; and fish showed the highest occurrence in June, July and August. The broad diet spectrum of the Amur sleeper indicates that it is a non-selective, opportunistic predator and that several taxonomic groups of native hydrofauna as well as macroinvetebrates and fish may be affected by its presence. The highly flexible feeding strategy undoubtedly favours Amur sleeper expansion in invaded watersheds.