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SUMMARY Cylindrospermopsis raciborskii and Sphaerospermopsis aphanizomenoides are increasingly widespread cyanobacterial species, considered invasive. However, they have never been found to dominate the phytoplankton in the northern part of the invaded area. The aim of our study was to expand the understanding of the invasion process in Nostocales, by answering the question which environmental conditions enabled the first ever noted bloom incident of C. raciborskii and S. aphanizomenoides in the northern part of their current occurrence ranges. We examined the population dynamics of the two invasive cyanobacteria and the abiotic conditions in which their blooms developed in a reservoir at 52° N. We also examined the phytoplankton community diversity and composition before and during the invasive species blooms . As shown by redundancy analysis, the competitive advantage of S. aphanizomenoides depended strongly on high water temperature and high concentration of phosphates, and was positively related to other summer conditions (low water transparency, high ammonium nitrogen concentration). C. raciborskii biomass was not related to temperature and phosphates, but we argue that high water temperature in the first half of July enabled abundant akinete germination, and pulsed phosphorus availability synergized to bring about a later bloom. Both the invasive species co-occurred with the native cyanobacterium Aphanizomenon gracile, but C. raciborskii bloomed after the native species domination period. The results of the study corroborate the high competitiveness of S. aphanizomenoides in hot, nutrient-rich conditions, and the adaptation of the invaders to the environment in the invaded regions, inter alia by the overwintering mechanism of numerous akinete differentiation. Our results also contradict the assumption that the phytoplankton diversity index would decrease after colonization of freshwater bodies by invasive cyanoprokaryotes. [ABSTRACT FROM AUTHOR]

Sustainable management of lakes requires us to overcome ecological, economic, and social challenges. These challenges can be addressed by focusing on achieving ecological improvement within a multifaceted, co-beneficial context. In-lake restoration measures may promote more rapid ecosystem responses than is feasible with catchment measures alone, even if multiple interventions are needed. In particular, we identify restoration methods that support the overarching societal target of a circular economy through the use of nutrients, sediments, or biomass that are removed from a lake, in agriculture, as food, or for biogas production. In this emerging field of sustainable restoration techniques, we show examples, discuss benefits and pitfalls, and flag areas for further research and development. Each lake should be assessed individually to ensure that restoration approaches will effectively address lake-specific problems, do not harm the target lake or downstream ecosystems, are cost-effective, promote delivery of valuable ecosystem services, minimize conflicts in public interests, and eliminate the necessity for repeated interventions. Achieving optimal, sustainable results from lake restoration relies on multidisciplinary research and close interactions between environmental, social, political, and economic sectors. This article is categorized under: Science of Water > Water Quality Water and Life > Stresses and Pressures on Ecosystems Water and Life > Conservation, Management, and Awareness [ABSTRACT FROM AUTHOR]

We present a 22-year-old male who developed a severe erosive oesophagitis extending to the pharynx and oral cavity without obvious risk factors. Endoscopic image suggested viral aetiology that could not be confirmed by routine serological diagnostics of infections with cytomegalovirus, Epstein-Barr virus, and Herpes simplex virus. The histopathological evaluation also gave no definite clues to the aetiology of the inflammation. Treatment with acyclovir was ineffective, but gancyclovir therapy caused spectacular clinical improvement and healing of erosions. Two months later the patient presented febrile diarrhoea that was a symptom of ileocecal Crohn's disease proven by endoscopy, enterography, and histopathology. It is the first report of severe viral oesophagitis preceding clinical manifestation of Crohn's disease. This observation warrants further study towards the viral aetiology of oral, pharyngeal, and oesophageal erosions, frequently associated with Crohn's disease. [ABSTRACT FROM AUTHOR]

• Northern aquatic ecosystems are most threatened by the presence of cyanobacteria species that produce neurotoxins. • Periods of heat waves could favour an increase in toxic cyanobacterial blooms, especially in northern cool lakes. • Nutrients are also a very important factor directly enhancing blooms across latitudes in central Europe. • The cyanobacteria species that dominate in blooms might be recognized as ecological indicators of eutrophication, but also of climate change. Climate change has increased the frequency, duration and intensity of heatwaves in Europe. These extreme events result in alterations of physical, chemical, and biological properties of lakes that may synergistically promote cyanobacterial dominance. In our study we focused on cyanobacterial blooms in lakes distributed over a longitudinal gradient in Central Europe during one of the "top ten European heat waves" in summer 2015. 92 lakes were included in the study, located across three climatic subregions: cool northern lakes, situated in Lithuania, temperate northern lakes in Poland, and warm northern lakes in Croatia. The objective of the study was to determine if cyanobacterial biomass, predominant species, and cyanotoxin concentration differed, across the south-north gradient, as a function of water temperature, total phosphorus, and total nitrogen. Statistical significance of observed patterns was tested using the Kruskal-Wallis rank sum test and the generalized linear model. We found the lowest average epilimnion temperature, but the highest average cyanobacterial biomass in the northern, 'cool' lakes while the highest average temperature with the lowest average cyanobacterial biomass in the southern, 'warm' lakes. The concentration of cyanotoxins was also the highest in the 'cool' lakes. Total phosphorus and total nitrogen correlated significantly with cyanobacterial biomass, cyanotoxins concentration and biomass of some cyanobacterial species (mainly Planktothrix agardhii), regardless of the latitude. Only in the 'cool' lakes concentration of cyanotoxins (microcystins and anatoxin-a) correlated significantly with cyanobacterial biomass and the biomass of some dominant cyanobacterial species (P. agardhii). Our results emphasized the differences of heat weaves impact on lakes of various latitudes, with the strongest increase in toxic cyanobacterial blooms in northern 'cool' lakes, situated in high latitudes. On the other hand, nutrients directly enhanced blooms across all the studied latitudes of Central Europe. The cyanobacteria species dominating in blooms might be recognized as ecological indicators of climate change, especially in the north-eastern part of Europe. [ABSTRACT FROM AUTHOR]

Highlights • An innovative sustainable lake restoration method by nitrate treatment was proposed. • Nitrate-rich and well-oxidized subsurface waters were delivered into lake hypolimnion to increase the redox potential and reduce internal phosphorus loading. • Phosphorus concentrations in lake waters were diminished as well as chlorophyll-a content in epilimnetic waters. • Cyanobacteria biomass was reduced on the benefit of diatoms and cryptophytes. Abstract The aim of nitrate treatment as a restoration method is to bring about a reduction of the high potential reactivity of sediments by the oxidation of biodegradable organic matter. As a consequence, oxygen uptake by sediments is reduced, sulphate reduction is lowered, hydrogen sulphide formation diminished and iron present in sediments binds phosphorus (P) effectively. This approach was applied in Uzarzewskie Lake, where innovative nitrate treatment of sediments was proposed through the diversion of subsurface waters to the lake hypolimnion. Nitrate-rich and oxygenated water from two tributaries was directly delivered to the hypolimnion through pipelines in order to increase redox potential and eliminate sediments as a P source. Research on selected physico-chemical and biological water characteristics was conducted in the years 2005–2015 to determine the results of restoration measures. P concentrations in lake waters were reduced both in surface water layers and the hypolimnion, hence epilimnetic chlorophyll-a content was diminished as well. Statistically significant changes in phytoplankton community structure were noted as the biomass of cyanobacteria had decreased in 2010 and 2013–2014 in comparison to 2006, while cryptophytes biomass increased in 2011–2013 in relation to 2007. Unfortunately, planktivorous fish domination in fish fauna exert a distinct pressure on zooplankton, thus Rotifera dominated and Cladocera were rarely noted. Additionally, the morphometric lake features (steep slopes, small surface surrounded by forest) create unfavorable conditions for submerged macrophyte development, and hinder the effectiveness of the restoration. Long-term studies revealed that the reconstruction of the phytoplankton community was not permanent, hence further restoration activity is required, with the inclusion of new techniques. [ABSTRACT FROM AUTHOR]

In this work, the authors examined the presence of cyanobacteria and cyanotoxins in 21 samples collected from fresh water bodies located in 5 provinces in Poland: Lublin (2), Podlasie (1), Pomerania (6), Warmia-Masuria (1) and Wielkopolska (11). In addition, to determine the general pattern of geographical distribution, frequency of cyanobacteria occurrence, and cyanotoxins production, the published data from 238 fresh water bodies in Poland were reviewed. On the basis of these collected results, we concluded that Planktothrix, Aphanizomenon, Microcystis and Dolichospermum were dominant. The general pattern in geographical distribution of the identified cyanobacterial genera was typical of other eutrophic waters in Europe. The production of cyanotoxins was revealed in 18 (86%) of the 21 samples analyzed in the present work and in 74 (75%) of the 98 total water bodies for which the presence of toxins had been examined. Among the 24 detected microcystin variants, [Asp3]MC-RR was most common. These results can be verified when more data from the less explored water bodies in the southern and eastern parts of Poland are available. [ABSTRACT FROM AUTHOR]

Lake Rusalka is a shallow, artificial, strongly eutrophic reservoir. Thermal stratification is weak and comprises only about 8% of the bottom surface. In summer, the epilimnion is oversaturated with oxygen due to intensive phytoplankton growth (chlorophyll a up to 80.2 μg l-1), while conditions in the hypolimnion are anaerobic. The high concentration of ammonium nitrogen and low N:P ratio stimulated intense growth of cyanobacteria in the period from June to November. The domination of rotifers in the metazooplankton and low diversity and biomass of benthic macroinvertebrates was the cause of low top-down pressure of these organisms on the phytoplankton. The most advantageous restoration measures were identified to improve water quality and make the recreational use of the lake possible. [ABSTRACT FROM AUTHOR]

Introduction. Alcohol abuse among the youth is a pressing social issue. It is not only related to one's individual susceptibility to risky or harmful drinking but also the issue of one's family living with the individual that abuses alcohol. It needs emphasizing that alcohol consumption is on the rise and the age at which young people have their first alcoholic drink is declining as well. Also, girls tend to drink as much as boys. Aim. The aim of this work was to investigate the issue of alcohol abuse among young people of school age and the relationship between the following variables: school educational level, sex, satisfaction with home life and drinking patterns. Material and methods. The authors interviewed some 1444 students of 32 schools (12 elementary schools, 10 junior high schools and 10 high schools) chosen at random, using an anonymous questionnaire. The collected data were analyzed statistically, taking the following factors into consideration: sex, school level, atmosphere at home. Results and conclusions. One's sex, school level and satisfaction with home life had influence over the respondents' answers concerning alcohol consumption. The research study shows that students of schools at all levels drink alcohol - high school students drink vodka, junior high school students (gimnazjum in Polish) prefer beer, while elementary school students, who tend to drink the least, prefer wine. Interestingly enough, boys are drinking more than girls, yet girls are more likely to try all types of alcohol. Children who reported good atmosphere at home are less likely to drink, while in case of troubled homes, only every eighth respondent does not drink. The atmosphere at home also affects one's drinking habits. Most of the respondents have no idea about ways of helping people addicted to alcohol. [ABSTRACT FROM AUTHOR]

Abstract: The resistance of Helicobacter pylori to antimicrobials, known to be increasing in many countries, is an important factor compromising the efficacy of eradication therapy. Therefore, our study aimed at analysing the current susceptibility status of H. pylori in Poland. A total of 337 H. pylori isolates were cultured from children (N =179) and adults (N =158) from various regions of the country from January 2001 to December 2004. All strains were susceptible to amoxicillin and tetracycline. The overall resistance to clarithromycin (CL) was 28%, but there were significant differences between the centres (ranging from 0% to 33%) and between child and adult isolates (28% versus 15%, respectively; P =0.01) for primary a resistance. Altogether, 46% of H. pylori isolates were resistant to metronidazole (MTZ) and 20% of isolates were simultaneously resistant to CL and MTZ. [Copyright &y& Elsevier]

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. [ABSTRACT FROM AUTHOR]