ABSTRACT
Although the phylogeography of European mammals has been extensively investigated since the 1990s, many studies were limited in terms of sampling distribution, the number of molecular markers used and the analytical techniques employed, frequently leading to incomplete postglacial recolonisation scenarios. The broad-scale genetic structure of the European badger (Meles meles) is of interest as it may result from historic restriction to glacial refugia and/or recent anthropogenic impact. However, previous studies were based mostly on samples from western Europe, making it difficult to draw robust conclusions about the location of refugia, patterns of postglacial expansion and recent demography. In the present study, continent-wide sampling and analyses with multiple markers provided evidence for two glacial refugia (Iberia and southeast Europe) that contributed to the genetic variation observed in badgers in Europe today. Approximate Bayesian computation provided support for a colonisation of Scandinavia from both Iberian and southeastern refugia. In the whole of Europe, we observed a decline in genetic diversity with increasing latitude, suggesting that the reduced diversity in the peripheral populations resulted from a postglacial expansion processes. Although MSVAR v.1.3 also provided evidence for recent genetic bottlenecks in some of these peripheral populations, the simulations performed to estimate the method's power to correctly infer the past demography of our empirical populations suggested that the timing and severity of bottlenecks could not be established with certainty. We urge caution against trying to relate demographic declines inferred using MSVAR with particular historic or climatological events.
Subject(s)
Evolution, Molecular , Genetic Variation , Genetics, Population , Mustelidae/genetics , Animals , Bayes Theorem , DNA, Mitochondrial/genetics , Europe , Haplotypes , Microsatellite Repeats , Models, Genetic , Phylogeography , Population DynamicsABSTRACT
Rabid bats are regularly reported in Europe, especially in countries that have implemented a bat surveillance network. In May 2013, bat rabies was evidenced for the first time in Luxembourg (southern city of Differdange). The rabies virus, an EBLV-1b strain, was diagnosed in a serotine bat that bit a 29-year-old male person while he was asleep. The man received rapidly a post-exposure RABV treatment and was put under strict medical supervision.
Subject(s)
Bites and Stings/virology , Chiroptera/virology , Lyssavirus/isolation & purification , Rabies/transmission , Adult , Animals , Databases, Nucleic Acid , Europe , Humans , Luxembourg , Lyssavirus/genetics , Male , Molecular Sequence Data , Rabies/prevention & control , Rabies Vaccines/administration & dosage , Rabies virus/genetics , Rabies virus/isolation & purification , Real-Time Polymerase Chain Reaction , Rhabdoviridae Infections , Sequence AnalysisABSTRACT
The non-enzymatic glycosylation of beta-amyloid is implicated in the aetiology of Alzheimer's disease. However, controversy surrounds the nature of any involvement and a potential mechanism has not been fully elucidated. We present evidence of an aluminium-induced aggregation of the A beta P(25-35) peptide and speculate that the mechanism of formation of our ordered beta-amyloid aggregates might involve non-enzymatic glycosylation and/or site-specific crosslinking of beta-amyloid fibrils by atomic aluminium.
Subject(s)
Aluminum/toxicity , Amyloid beta-Peptides/chemistry , Amyloid beta-Peptides/drug effects , Alzheimer Disease/etiology , Amyloid beta-Peptides/ultrastructure , Cross-Linking Reagents , Glycosylation , Humans , In Vitro Techniques , Macromolecular Substances , Microscopy, Electron , Protein Conformation/drug effectsABSTRACT
Molecular forensic methods are being increasingly used to help enforce wildlife conservation laws. Using multilocus genotyping, illegal translocation of an animal can be demonstrated by excluding all potential source populations as an individual's population of origin. Here, we illustrate how this approach can be applied to a large continuous population by defining the population genetic structure and excluding suspect animals from each identified cluster. We aimed to test the hypothesis that recreational hunters had illegally introduced a group of red deer into a hunting area in Luxembourg. Reference samples were collected over a large area in order to test the possibility that the suspect individuals might be recent immigrants. Due to isolation-by-distance relationships in the data set, inferring the number of genetic clusters using Bayesian methods was not straightforward. Biologically meaningful clusters were only obtained by simultaneously analysing spatial and genetic information using the program baps 4.1. We inferred the presence of three genetic clusters in the study region. Using partial Mantel tests, we detected barriers to gene flow other than distance, probably created by a combination of urban areas, motorways and a river valley used for viticulture. The four focal animals could be excluded with a high certainty from the three genetic subpopulations and it was therefore likely that they had been released illegally.
Subject(s)
Deer/genetics , Genetics, Population/methods , Animal Migration , Animals , Cluster Analysis , Conservation of Natural Resources/legislation & jurisprudence , Conservation of Natural Resources/methods , DNA/chemistry , DNA/genetics , Data Interpretation, Statistical , Europe , Female , Genetic Variation , Genotype , Hair , Male , Microsatellite Repeats/genetics , Polymerase Chain Reaction/veterinary , Population Dynamics , Sequence Analysis, DNA , Transportation/legislation & jurisprudenceABSTRACT
We investigated fine-scale genetic structuring in the rare and vulnerable Mallorcan midwife toad Alytes muletensis using eight polymorphic microsatellite markers. The current range of this amphibian is restricted to some 19 sites of which six are derived from reintroductions, all located in the mountain ranges of Mallorca. We sampled tadpoles from 14 pools covering 10 natural sites and two reintroduction sites for microsatellite DNA analyses. Relatively high levels of genetic variation were found in most pools (H(E) = 0.38-0.71, allelic richness = 2.6-6.2). Only at one pool has the population recently gone through a bottleneck. Dispersal between pools in different torrents does not occur whereas downstream dispersal between pools within the same torrent does happen at low frequencies. This occasional exchange of individuals does not lead to neighbouring pools in the same torrent being panmictic. This can be concluded because all F(ST) values (0.12-0.53) differ significantly from zero and STRUCTURE analyses identified neighbouring pools as separate populations. Furthermore, assignment and migration tests showed little exchange between neighbouring pools. If upstream locations or complete torrents go extinct, they are unlikely to be recolonized naturally. For conservation purposes, reintroductions of tadpoles to sites where local extinctions have occurred may therefore be advisable.
Subject(s)
Anura/genetics , Genetic Variation , Genetics, Population , Phylogeny , Animals , Conservation of Natural Resources , DNA Primers , Fresh Water , Gene Frequency , Geography , Heterozygote , Microsatellite Repeats/genetics , SpainABSTRACT
Peroxidase, isolated from B16 mouse melanoma, converted tyrosine to dopachrome in the presence of either dopa or dihydroxyfumarate co-factor. A suspended homogenate of cloned, cultured B16 mouse melanoma cells also showed peroxidatic conversion of tyrosine to dopachrome in the presence of dihydroxyfumarate co-factor. The findings confirm previous histochemical, autoradiographic-histochemical, and EM-histochemical studies showing that melanoma peroxidase can convert tyrosine to melanin.
Subject(s)
Indolequinones , Indoles/metabolism , Isoenzymes/metabolism , Melanoma/metabolism , Peroxidases/metabolism , Quinones/metabolism , Tyrosine/metabolism , Animals , Clone Cells/metabolism , In Vitro Techniques , Melanins/biosynthesis , Mice , Mice, Inbred C57BL , Neoplasms, Experimental/metabolism , PeroxidaseABSTRACT
Through December 1986, coronary artery bypass surgery was performed on 150 patients who had undergone at least two previous myocardial revascularization surgeries. One hundred thirty-seven patients had two, 12 patients had three, and one patient had four previous operations. There were 117 men (78.0%); the mean age was 55.5 years (range, 28-76 years); 137 patients (91.3%) had triple-vessel disease, and 36 (24.0%) had a left ventricular ejection fraction less than 0.40. One hundred forty-nine patients (99.3%) had angina preoperatively, with 142 (94.7%) having Class III and IV angina. Direct myocardial revascularization was performed in all patients, with a mean of 3.3 grafts per patient (range, 1-6). In addition, coronary artery endarterectomy was performed in 70 cases (46.7%): right coronary artery endarterectomy in 15 (10.0%), left coronary artery endarterectomy in 39 (26.0%), and multiple coronary artery endarterectomies in 16 (10.7%). There were 18 in-hospital deaths (12.0%). Statistically significant risk factors for increased early mortality (p less than 0.01) included age over 65 years and left ventricular ejection fraction less than 0.40. Diffuse coronary artery disease requiring multiple coronary artery endarterectomies almost achieved statistical significance as a risk factor (p = 0.06). Complications in the surviving 132 patients included seven nonfatal perioperative myocardial infarctions (5.3%). Follow-up data for a period of 8-172 months (mean, 43.1 months) is available for 100 of 103 patients (97.1%). Five-year actuarial survival was 76.4% for the entire series and 87.3% for hospital survivors.(ABSTRACT TRUNCATED AT 250 WORDS)
Subject(s)
Coronary Artery Bypass , Adult , Aged , Coronary Disease/pathology , Coronary Disease/surgery , Coronary Vessels/pathology , Female , Follow-Up Studies , Humans , Male , Middle Aged , Postoperative Complications/mortality , Reoperation , Vascular PatencyABSTRACT
The activity levels of Mallorcan midwife toad tadpoles, Alytes muletensis, were compared in two natural torrent pools which differed in their use by predatory viperine snakes, Natrix maura. Activity levels were lower in a pool regularly used by snakes than they were in a snake-free pool, but were reduced in both pools when snakes were experimentally introduced in nylon bags. In the presence of snakes, however, activity was more suppressed in the pool that was usually snake-free. Corresponding reductions in activity were also observed when tadpoles were treated with chemical cues from Mallorcan N. maura in a gravitational flow-through system. However, tadpoles failed to respond to chemical cues from other species of amphibian-eating snakes, or even to those from N. maura collected from a different population in mainland Spain. As none of the snakes used had previously eaten midwife toads, the responses cannot be related to previous diet, and seem to be specific to those N. maura from the island of Mallorca. As viperine snakes were probably introduced to Mallorca about 2000 years ago, the evolution of anti-predator behaviour in midwife toad tadpoles must have occurred relatively recently. Copyright 1998 The Association for the Study of Animal Behaviour.