Occurrence of Vibrio parahaemolyticus, V. cholerae, and V. vulnificus in Norwegian Blue Mussels (Mytilus edulis)

Vibrio parahaemolyticus, V. cholerae, and V. vulnificus were isolated from 10.3%, 1.0%, and 0.1% of 885 blue mussel samples, respectively. Four of the samples contained trh(+) V. parahaemolyticus, while no tdh-positive isolates were detected. The V. cholerae isolates were non-O:1/non-O:139 serotypes and were ctxA negative.     

Application of rapid enzyme assay techniques for monitoring of microbial water quality

Rapid enzyme assay techniques based on direct measurement of beta-d-galactosidase (GALase) or beta-d-glucuronidase (GLUase) activity without selective cultivation are used for rapid estimation of the level of coliform bacteria and Escherichia coli in water samples. Reported detection limits using fluorogenic substrates correspond to culturable target bacteria concentrations that can be appropriate within present guidelines for recreational waters. The rapidity, that is detection within one hour, compromises the specificity of the assay; enzyme activity contributions from other than target bacteria need to be considered, particularly at low levels of target bacteria. Enzyme activities are more persistent than the culturability of target bacteria to environmental and disinfection stress, thus water samples may express enzyme activities of both culturable and viable non-culturable cells.     

Phylogeographic origin and genetic diversity of dunlin <Emphasis Type="Italic">Calidris alpina</Emphasis> in Svalbard

We investigated the genetic structure of the presumably small (10–100 pairs) and isolated dunlin (Calidris alpina) population breeding in Svalbard, and compared it with similar data recently published from several dunlin populations in the western Palearctic and East Greenland. Using mitochondrial and nuclear DNA markers, as well as data on bill lengths, we sought to infer the phylogeographic origin of Svalbard dunlins and assess their within-population level of genetic diversity. Only dunlins with haplotypes of the European mtDNA clade (EUR) were found in Svalbard, indicating a close resemblance to dunlin populations in East Greenland and Iceland. Microsatellite data for Svalbard dunlins, as well as their short bills, also supported a western origin. The Svalbard population did not show signs of inbreeding or reduced levels of genetic diversity compared to other investigated populations, which suggests that the population was recently founded or is currently subject to considerable gene flow.     

Human Borna disease virus infection in Australia: serological markers of infection in multi-transfused patients

Borna disease virus (BDV) causes neurological disease in horses, however, there is no consensus as to the extent or significance of human infection. BDV antigen levels in plasma (BDVpAg) and anti-BDV were measured by ELISAs. Confirmation was by Western blot (WB), immunofluorescence assay (IFA) or BDV-peptide-epitope ELISA. For 42 volunteers psychiatrically-defined as non-depressed (82 samples) neither BDVpAg nor anti-BDV was detected. For 104 patients with diagnosed depression (290 samples) 1 was BDVpAg positive and 5 anti-BDV positive, one epitope-e8 positive and 4 IFA positive, with 96% concordance for repeat samples. No BDVpAg was detected in 214 pregnant women, 2 were anti-BDV positive, one WB-confirmed (p24/p40). For 219 donors 2 were BDVpAg positive with anti-BDV detected in 5 (2.3%) one IFA 1:10, another IFA 1:40/epitope-e8 positive. In multitransfused patients, 3/168 were BDV pAg positive, with 14/168 anti-BDV positive, 1 epitope-e8 positive, 2 WB positive and 1 IFA 1:10. In BDVpAg positive multi-transfused patients there was an elevated risk of transaminitis. In one case, a patient BDV-negative prior to transfusion was BDVpAg positive for several months posttransfusion (associated with transaminitis). These data provide serological evidence, supported by confirmatory assays and repeat-sample concordance, of BDV infection in Australia, particularly in multi-transfused patients.     

Human Borna disease virus-infection and its therapy in affective disorders

Patients with affective disorders show an enhanced prevalence of Borna disease virus (BDV)-infection. Furthermore, BDV causes latent infection preferably in limbic central nervous structures and is suggested to be causally related to subtypes of affective disorders, especially with melancholic clinical features or bipolarity. Such a possible link was highlighted by the first report of amantadine showing an antidepressive and an antiviral efficacy against BDV in a patient with a bipolar disorder. This article summarizes clinical studies which followed this first report on the use of amantadine in BDV-infected patients with an affective disorder. A special focus is given on an open clinical study in patients with depression (n = 25), a study in remitted patients with affective disorders (n = 16), and the effect of amantadine on severe hypomanic or moderately manic patients with a bipolar disorder in an on-off-on study. In these studies amantadine reduced clinical symptoms paralleled by a reduction of BDV-infection in depressive patients, it also reduced all three BDV-parameters (BDV-Ab, -AG, and -CICs) in remitted patients, and it even reduced severe hypomania and moderate mania in bipolar patients. These data suggest the existence of an etiopathogenetic link between BDV and subtypes of affective disorders.     

Geographical segregation in Dunlin Calidris alpina populations wintering along the East Atlantic migratory flyway – evidence from mitochondrial DNA analysis

Dunlin Calidris alpina is one of the most abundant shorebirds using coastal habitats in the East Atlantic migratory flyway, that links arctic breeding locations (Greenland to Siberia) with wintering grounds (West Europe to West Africa). Differential migration and winter segregation between populations have been indicated by morphometrics and ringing recoveries. Here, we analyse the potential of genetic markers (mitochondrial DNA – mtDNA) to validate and enhance such findings. We compared mtDNA haplotypes frequencies at different wintering sites (from north-west Europe to West Africa). All birds from West Africa had western (European) haplotypes, while the eastern (Siberian) haplotypes were only present in European winter samples, reaching higher frequencies further north in Europe. Compilation of published results from migrating birds also confirmed these differences, with the sole presence of European haplotypes in Iberia and West Africa and increasingly higher frequencies of Siberian haplotypes from south-west to north-west Europe. Comparison with published haplotype frequencies of breeding populations shows that birds from Greenland, Iceland, and North Europe were predominant in wintering grounds in West Africa, while populations wintering in West Europe originated from more eastern breeding grounds (e.g. North Russia). These results show that genetic markers can be used to enhance the integrative monitoring of wintering and breeding populations, by providing biogeographical evidence that validate the winter segregation of breeding populations.     

Cold acclimation in warmer extended autumns impairs freezing tolerance of perennial ryegrass (Lolium perenne) and timothy (Phleum pratense)

The effect of variable autumn temperatures in combination with decreasing irradiance and daylength on photosynthesis, growth cessation and freezing tolerance was investigated in northern‐ and southern‐adapted populations of perennial ryegrass (Lolium perenne) and timothy (Phleum pratense) intended for use in regions at northern high latitudes. Plants were subjected to three different acclimation temperatures; 12, 6 and 9/3°C (day/night) for 4 weeks, followed by 1 week of cold acclimation at 2°C under natural light conditions. This experimental setup was repeated at three different periods during autumn with decreasing sums of irradiance and daylengths. Photoacclimation, leaf elongation and freezing tolerance were studied. The results showed that plants cold acclimated during the period with lowest irradiance and shortest day had lowest freezing tolerance, lowest photosynthetic activity, longest leaves and least biomass production. Higher acclimation temperature (12°C) resulted in lower freezing tolerance, lower photosynthetic activity, faster leaf elongation rate and higher biomass compared with the other temperatures. Photochemical mechanisms were predominant in photoacclimation. The northern‐adapted populations had a better freezing tolerance than the southern‐adapted except when grown during the late autumn period and at the highest temperature; then there were no differences between the populations. Our results indicate that the projected climate change in the north may reduce freezing tolerance in grasses as acclimation will take place at higher temperatures and shorter daylengths with lower irradiance.     

Geographical variation in the timing of breeding and moult in dunlin Calidris alpina on the Palearctic tundra

Studies of how organisms are adapted to regional climatic conditions are valuable when predicting the effects of global climatic changes on biota. Here we report on the geographical variation in timing of breeding and moult of an Arctic breeding wader, the dunlin (Calidris alpina). The Palearctic study sites range latitudinally between 68 and 76°N and longitudinally between 46 and 179°E, and encompass a variety of local climates. The sites were visited in sequence from west to east within 1 year, and therefore the data are not affected by confounding interannual variations. The estimated breeding start ranged from 5 to 25 June across populations. Birds at more southern sites were found to breed earlier than those at more northern breeding sites. Within populations, the breeding start for first clutches spanned a period of 8 days and, when including replacement clutches, 3-4 weeks. No dunlin west of the Taimyr Peninsula were found moulting while incubating at the nest, whereas all dunlin on Taimyr Peninsula and eastwards were in active wing moult while incubating or rearing chicks. The onset of moult in these populations ranged from 23 to 27 June. The consequences of geographical variation of breeding conditions for variation in the annual cycle of this species are discussed.