Aromatase expression in testes of XY, YY, and XX rainbow trout (Oncorhynchus mykiss)

The main goal of the present study was to show whether testicular cells of rainbow trout (Oncorhynchus mykiss Walbaum) either hormonally manipulated (XX males) or produced by using gamma irradiation and pressure shock (YY males, "supermales") are able to aromatize androgens into estrogens compared with the control (XY males). The expression of aromatase gene at the level of the protein and its presence in testicular tissue was investigated by means of immunohistochemistry and Western blot analysis, respectively. The positive staining for aromatase was detected in testicular cells of all trout and in efferent duct cells of XY and YY males. However, the staining intensity varied among particular trout, being strong in YY males, moderate in XY males, and weak in XX trout. It was confirmed by quantitative image analysis in which the staining intensity was expressed as relative optical density (ROD) of diaminobenzidine deposits. Significant differences were found between XY and YY trout ((**)p<0.01) and XY and XX trout ((*)p<0.05). Such differences could reflect various levels of estrogens, possibly dependent on the genetic background of the trout studied. It seems likely that differential expression of the enzyme, especially that of weak or strong intensity, causes some alterations in testicular morphology of homogametic trout. Additionally, the results indicate that an imbalance in sex hormone biosynthesis may provoke the functional alterations in testes of YY males, and, in consequence, negatively affect the fertility of "supermales".     

Mathematical inference of the underground clonal growth of Epipactis helleborine (L.) Crantz (Orchidaceae, Neottieae)

Epipactis helleborine (L.) Crantz (Orchidaceae, Neottieae) can spread by sexual or vegetative propagation. The choice of strategy likely depends on the environmental conditions. The rhizome is the organ of vegetative reproduction; hence, it is crucial to understand its development. Unfortunately, it is hardly possible to investigate rhizome morphology directly, since E. helleborine is a protected species in most European countries. The goal of our investigation was to infer the growth patterns of underground parts of an orchid population from long-term annual observations of its aboveground shoots. We implemented the Minimum Spanning Tree method to determine a likely set of underground connections between shoots and to simulate the annual growth of new rhizomes. Furthermore, we modelled the spatial distribution of shoots with a density kernel estimator to compare the density gradients with the direction of growth of the rhizomes. Observed shoot numbers fluctuated between 72 and 183 from year to year. Our results suggest that (1) vegetative reproduction prevails in the studied population, (2) the population consists of about a dozen clones with a diameter of up to 6 m, (3) rhizomes produce up to five new shoots at one branch end per year, (4) rhizomes develop in the direction of decreasing population density, and (5) nodes of rhizomes may produce new offshoots after up to 7 years of dormancy.     

Tremor, seizures and psychosis as presenting symptoms in a patient with chronic lyme neuroborreliosis (LNB)

Lyme borreliosis is a multisystem disorder caused by Borrelia burgdorferi (Bb). Neurological symptoms such as lymphocytic meningoradiculoneuritis (Bannwart's syndrome), cranial neuritis (II,III,IV,V,VI), encephalitis, transverse myelitis are found in about 10% of cases during the second phase of the disease. In the chronic stage, many months or years after the initial infection, other neurologic complications may occur, such as encephalomyelitis, epileptic crises, cognitive impairment, peripheral neuropathy and psychiatric disturbances such as depression, anxiety, panicc attacks, catatonia, psychosis etc. Some patient continue to experience symptoms of fatigue, insomnia or psychiatric disorder in the post borrelia syndrome. We describe here a patient with a triad of unusual symptoms in chronic LNB including tremor, seizures and psychosis. Standardized medical interview, neurologic examination, neuroimaging, serum and CSF serology as well as EEG and EMNG evaluation were performed. The patient was treated with intravenous ceftriaxone and doxycycline and responded with rapid clinical and functional improvement.Newertheless, he suffered from multiple systemic and neurologic sequelas that influenced his daily activities in post treatment period. Emphasis is placed on the atypical onset and evolution, the difficulties encountered in formulating diagnosis, early treatment and the uncertainties concerning the sequelae after treatment. In patients with non-specific long lasting symptoms in the absence of overt clinical signs suggesting CNS involvement, routine treatment with i.v. ceftriaxone is not to be encouraged.     

Social Calls Provide Tree‐dwelling Bats with Information about the Location of Conspecifics at Roosts

Animals can use signals emitted by other animals as sources of information. Auditory signals are important in communication networks, as they can potentially convey information about the location and state of conspecifics and other species over long distances. Signalling is important in fission–fusion societies, in which animals from the same social group temporarily split into subgroups and frequently change roost sites. We used playbacks of social calls of the noctule Nyctalus noctula produced in roosts, to show how bats might maintain group cohesion and to test the hypothesis that noctules can locate conspecifics when returning from foraging trips by eavesdropping on or communicating with roosting individuals. Noctules responded strongly to broadcasted social calls. Their reactions included inspections and landing on a loudspeaker broadcasting social calls and occasional social vocalisation. Responses by other bat species to the noctule social calls were negligible. The high amplitude, low‐frequency vocalisations emitted by noctules in roosts can propagate over long distances and allow group members to announce their position. Bats can extract information about the location of roosts containing conspecifics by eavesdropping or by communication. Social calls may thus be sufficient to locate conspecifics in roosts and maintain spatial associations of groups in mammals.     

Melanin‐based coloration covaries with fluctuating asymmetry,nutritional state and physiological stress response in common snipe

Adaptative significance of melanin‐based coloration in birds remains poorly recognized. It has been suggested that genes responsible for melanin synthesis may have pleiotropic effect on several physiological and behavioural functions, including immune defence. For this reason, we could expect that the expression of melanin‐based plumage coloration should covary with different condition‐related phenotypic traits via regulation of pathogen/parasite resistance. The aim of this study was to test this hypothesis in common snipe Gallinago gallinago, a species that exhibits conspicuous variation in the black eumelanism of underwing plumage. The study was conducted in central Poland, where common snipe were captured during autumn migration. We found that after accounting for the effects of age, sex and date of capture, underwing coloration correlated with nutritional state of snipes, as more extensively melanised individuals had higher plasma concentrations of triglycerides, total protein and albumin. Dark underwing coloration was also associated with lower heterophil/lymphocyte (H/L) ratio, suggesting better resistance of eumelanic individuals to physiological stress. Finally, adult males with darker underwings had lower asymmetry in wing shape (wingtip convexity), which indicated their higher developmental stability. In conclusion, melanin‐based coloration may be considered an honest indicator of phenotypic quality in common snipe.     

Palaeoecological evolution of a spring-fed fen in Pawłów (eastern Poland)

A continuous record of sedimentation in spring-fed fens makes them suitable for detailed palaeoenvironmental studies. A newly investigated cupola spring-fed fen (Paw?ów site), located in the Lublin chalkland, eastern Poland, was the object of our study. This special karst region is characterised by the occurrence of Upper Cretaceous carbonate rocks in the substratum. Sedimentological observations indicated strong variability of biogenic-carbonate series in the deposits (=peat-tufa rhythmite), reflects changes of accumulation conditions (oxidising versus reducing), resulting from alternate occurrence of warmer and cooler periods. Difficulties in pollen analysis due to oxidising conditions necessitate a multidisciplinary approach for palaeoenvironmental reconstruction. We used a multidisciplinary approach (sedimentological, palaeobotanical, geochemical analyses and radiocarbon dating) to determine the main evolutionary stages of this unique fen ecosystem and to discuss the role of local or/and regional factors in its development. Pollen and plant macrofossil analyses, supported by radiocarbon dating, proved that the bottom part of the cores represents the Late Glacial–Early Holocene stages of the fen development. A comparative analysis of palaeoenvironmental data showed close resemblance between the Paw?ów fen and the earlier studied fens in eastern Poland and Central-Eastern Europe, and the connection between their development and supraregional hydrological-climatic factors. The results indicated also the influence of the morphological position of such a type of ecosystem on the development of a continuous deposit succession. The occurrence of a river valley in close proximity of the Paw?ów site resulted in the lack of tufa deposits from the Atlantic period, because of an erosional phase in the river valley.     

Removal of birch as a means of protecting raised bog mossy vegetation <Emphasis Type="Italic">Ledo</Emphasis>-<Emphasis Type="Italic">Sphagnetum magellanici</Emphasis>

Raised bogs dominated by the vegetation association Ledo-Sphagnetum magellanici Sukopp 1959 em. Neuhäusl 1969 are a valuable and ecologically important plant community that occurs in Central Europe. They develop in impervious depressions with precipitation as the only water source, and are particularly sensitive to drainage, climate change, eutrophication and overgrowing by trees and shrubs. The high pressure of threat justifies taking protective measures. This research focused on the effects of the removal of birch from two bogs, which were dominated by two birch species (Betula pubescens, B. pendula) and also included stands of Scots pine (Pinus sylvestris); the bogs are located in northeastern Poland and showed signs of drying. The trees were removed in early spring 2008. To capture the response to tree cutting, vegetation monitoring was performed for 7 years. The results were compared to pre-cutting environmental conditions (precipitation, temperature, air transpiration). At the first site, which was drained at the beginning of the twentieth century, the ground water level initially decreased; then, from 2010 onwards, the level stabilised and exhibited a negative correlation with the average annual air temperature. While the second site exhibited no significant differences in the ground water table, a correlation with the average annual rainfall was found. At both sites, there was an increase in the coverage of species appropriate for raised bogs, Oxycocco-Sphagnatea Br.-Bl. et R. Tx. 1943, whereas only the second site had significant coverage of these species. These actions improved the habitat conditions and initiated the process of raised bog restoration at that site because Oxycocco-Sphagnatea species cover and frequency increased.     

The Association between Sulfonylurea Use and All-Cause and Cardiovascular Mortality: A Meta-Analysis with Trial Sequential Analysis of Randomized Clinical Trials

BackgroundSulfonylureas are an effective and inexpensive treatment for type 2 diabetes. There is conflicting data about the safety of these drugs regarding mortality and cardiovascular outcomes. The objective of the present study was to evaluate the safety of the sulfonylureas most frequently used and to use trial sequential analysis (TSA) to analyze whether the available sample was powered enough to support the results.ConclusionsSulfonylureas are not associated with increased risk for all-cause mortality, cardiovascular mortality, myocardial infarction, or stroke. Current evidence supports the safety of sulfonylureas; an absolute risk of 0.5% could be firmly discarded.

Review registration

PROSPERO CRD42014004330