Successful reproduction and pheromone production by the spruce bark beetle in evolutionary naïve spruce hosts with familiar terpenoid defences

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Genome wide AFLP markers support cryptic species in Coniophora (Boletales)

Numerous fungal morphospecies include cryptic species that routinely are detected by sequencing a few unlinked DNA loci. However, whether the patterns observed by multi-locus sequencing are compatible with genome wide data, such as amplified fragment length polymorphisms (AFLPs), is not well known for fungi. In this study we compared the ability of three DNA loci and AFLP data to discern between cryptic fungal lineages in the three morphospecies Coniophora olivacea, Coniophora arida, and Coniophora puteana. The sequences and the AFLP data were highly congruent in delimiting the morphotaxa into multiple cryptic species. However, while the DNA sequences indicated introgression or hybridization between some of the cryptic lineages the AFLP data did not. We conclude that as few as three polymorphic DNA loci was sufficient to recognize cryptic lineages within the studied Coniophora taxa. However, based on analyses of a few (three) sequenced loci the hybridization could not easily be distinguished from incomplete lineage sorting. Hence, great caution should be taken when concluding about hybridization based on data from just a few loci.     

Proof-of-concept human laboratory study for protracted abstinence in alcohol dependence: effects of gabapentin

There is a need for safe medications that can effectively support recovery by treating symptoms of protracted abstinence that may precipitate relapse in alcoholics, e.g. craving and disturbances in sleep and mood. This proof-of-concept study reports on the effectiveness of gabapentin 1200 mg for attenuating these symptoms in a non-treatment-seeking sample of cue-reactive, alcohol-dependent individuals. Subjects were 33 paid volunteers with current Diagnostic and Statistical Manual of Mental Disorders-IV alcohol dependence and a strength of craving rating 1 SD or greater for alcohol than water cues. Subjects were randomly assigned to gabapentin or placebo for 1 week and then participated in a within-subjects trial where each was exposed to standardized sets of pleasant, neutral and unpleasant visual stimuli followed by alcohol or water cues. Gabapentin was associated with significantly greater reductions than placebo on several measures of subjective craving for alcohol as well as for affectively evoked craving. Gabapentin was also associated with significant improvement on several measures of sleep quality. Side effects were minimal, and gabapentin effects were not found to resemble any major classes of abused drugs. Results suggest that gabapentin may be effective for treating the protracted abstinence phase in alcohol dependence and that a randomized clinical trial would be an appropriate next step. The study also suggests the value of cue-reactivity studies as proof-of-concept screens for potential antirelapse drugs.     

A multivariate comparison between three NW. European populations ofArtemisia norvegica (Asteraceae) by means of chemometric and morphometric data

Specimens from Scotland, S. and C. Norway were grown in the botanical garden of Bergen, Norway. Some of the Scottish specimens came from a meristem tissue culture. The specimens were compared by a principal component analysis of lipids and related compounds, and of morphological characters from leaves and flowers. The populations differed from each other, but some overlap was found in leaf characters. The results are discussed in relation to distribution and immigration history, and it is argued that the differences among the populations may have evolved in postglacial time.     

Anti-complement effects of lactoferrin-derived peptides

Lactoferrin is an important biological molecule with many functions such as modulation of the inflammatory response, iron metabolism and antimicrobial defense. One effect of lactoferrin is the inhibition of the classical complement pathway. This study reports that antimicrobial peptides derived from the N-terminal region from both human and bovine lactoferrin, lactoferricin H and lactoferricin B, respectively, inhibit the classical complement pathway. No inhibitory effect of these peptides was observed on the alternative complement pathway in an AP50 assay. However, lactoferricin B reduced the inhibitory properties of serum against Escherichia coli in a concentration dependent manner. These results suggest that the N-terminal region of lactoferrin is the important part in the inhibition of complement activation and that these peptides possess other important properties than their antimicrobial effect.     

Anthocyanin from strawberry (Fragaria ananassa) with the novel aglycone, 5-carboxypyranopelargonidin

An anthocyanin, 1, with the novel 4-substituted aglycone, 5-carboxypyranopelargonidin, was isolated in small amounts from the acidified, methanolic extract of strawberries, Fragaria ananassa Duch., by preparative HPLC after purification by partition against ethyl acetate, Amberlite XAD-7 and Sephadex LH-20 column chromatography. It was identified mainly by 2D NMR spectroscopy and electrospray LC-MS as the 3-O-beta-glucopyranoside of 5-carboxy-2-(4-hydroxyphenyl)-3,8-dihydroxy-pyrano[4,3,2-de]-1-benzopyrylium, an anthocyanidin which is homologous to 5-carboxypyranomalvidin (vitisidin A) reported in red wines and 5-carboxypyranocyanidin recently isolated from red onions. By comparison of UV-Vis absorption spectra, 1 showed in contrast to 2, pelargonidin 3-O-beta-glucopyranoside, a local absorption peak around 360 nm, a hypsochromic shift (8 nm) of the visible absorption maximum, and lack of a distinct UV absorption peak around 280 nm. The similarities between the absorption spectra of 1 in various acidic and neutral buffer solutions implied restricted formation of the instable colourless equilibrium forms, which are typical for most anthocyanins in weakly acidic solutions. The molar absorptivity (epsilon) of 1 varied little with pH contrary to similar values of for instance the major anthocyanin in strawberry, 2. However, 2 revealed higher epsilon-values than 1 at all pH values except 5.1. At pH 5.1, the epsilon-value of 1 (6250) was nearly four times the corresponding value of 2 (1720), which showed the potential of 5-carboxypyranopelargonidin derivatives as colorants in solutions with pH around 5. The colours of 1 and 2 in buffered solutions with pH 1.1 and pH 6.9 have been described by the CIELAB coordinates h(ab) (hue angle), C* (chroma), and L* (lightness).     

Daphnicle dynamics based on kinetic theory: An analogue-modelling of swarming and behaviour of Daphnia

Attempts are presented of an analogue modelling of Daphnia responses to various influences and stimuli, as distribution of food and of predators. An aim of the study is to examine to what extent a statistical-mechanical approach may be useful as a tool in modelling of Daphnia swarms behaviour. In the modelling we follow a line close to test particle studies in physical sciences. A generalized kinetic equation of what we shall call daphnicles is derived. The modelling incorporates individual characteristics of daphnicles, as position, velocity, degree of food saturation and responses daphnicles have to outside influences. Each daphnicle we assume responds to some stimuli in ordered ways and to others in stochastic ways, and the degree or strength of reactions depends on the density of all daphnicles, the density of food available, the saturation level of daphnicles and the threat level in the environment, or background, the daphnicles are living on. Some fluid equations of daphnicle swarms are subsequently derived from the basic equation, and solutions are given of the model-equations, including a food distribution equation, in some particular cases that show peculiarities in reactions of daphnicles to food, degree of saturation and to threat, when these are acting alone, and in combination. The modelling results may be compared to results of laboratory experiments of Daphnia behaviour that soon will be performed.     

Freshwater bryozoans (Bryozoa) of Norway III: distribution and ecology of Plumatella fruticosa

Bryozoans were investigated during field studies of 601 lakes and other surface water bodies throughout Norway from 1960 to 1978. The frequency of occurrence of Plumatella fruticosawas evaluated in relation to 12 environmental variables. Statistically significant deviations from the frequencies expected on the basis of random distribution were described using the categories preference, avoidance, and absence. According to our material P. fruticosais one of the most common bryozoan species in Norwegian fresh water, represented in samples from 251 localities. This species occurred frequently all over the country, north to 71° 06 N (the northernmost record globally). Maximum elevation above sea level was 1179 m (maximum for Northern Europe).In most studies of freshwater bryozoans from the holarctic region, Plumatella fruticosahas been reported as widely distributed, but locally rare. In Norway, however, P. fruticosa is frequently found all over the country, even far to the north. The species apparently finds an optimal climate in the cold temperate and cold regions of Norway. Plumatella fruticosapreferred lakes, avoided slow-flowing rivers and ponds, and was absent in smaller water bodies. The species preferred somewhat higher elevation (400–900 m above sea level), but avoided lakes with the lowest summer temperatures (below 11 °C). P. fruticosa also preferred oligotrophic conditions with poor aquatic vegetation, stony shores, lakes poor in calcium and magnesium (sometimes almost comparable with distilled water), where the water was clear and colourless, and slightly acidic to neutral. The species also preferred lakes surrounded by Sphagnum bogs and was absent when pH was below 5.2. P. fruticosa avoided eutrophic conditions with rich aquatic vegetation, alkaline water (pH above 7.0), lakes with a higher content of calcium and magnesium and those with strongly coloured water (above 100 mg Pt l^–1). In spite of its preference for ion-poor conditions, it was also found in a brackish water lake. For most environmental variables, the species had a wider tolerance range than reported from elsewhere.