Metal Concentrations in Cerebrospinal Fluid and Blood Plasma from Patients with Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a progressive and fatal degenerative disorder of motor neurons. The cause of this degeneration is unknown, and different causal hypotheses include genetic, viral, traumatic and environmental mechanisms. In this study, we have analyzed metal concentrations in cerebrospinal fluid (CSF) and blood plasma in a well-defined cohort (n?=?17) of ALS patients diagnosed with quantitative electromyography. Metal analyses were performed with high-resolution inductively coupled plasma mass spectrometry. Statistically significant higher concentrations of manganese, aluminium, cadmium, cobalt, copper, zinc, lead, vanadium and uranium were found in ALS CSF compared to control CSF. We also report higher concentrations of these metals in ALS CSF than in ALS blood plasma, which indicate mechanisms of accumulation, e.g. inward directed transport. A pattern of multiple toxic metals is seen in ALS CSF. The results support the hypothesis that metals with neurotoxic effects are involved in the pathogenesis of ALS.     

Bloom forming Alexandrium ostenfeldii (Dinophyceae) in shallow waters of the Åland Archipelago,Northern Baltic Sea

In the past years, late summer blooms of the bioluminescent dinoflagellate Alexandrium ostenfeldii have become a recurrent phenomenon in coastal waters of the central and Northern Baltic Sea. This paper reports exceptionally high cell concentrations (10⁵ to 10⁶ cells L^?1) of the species found during bioluminescent blooms in 2003 and 2004 in a shallow embayment of the Åland archipelago at the SW coast of Finland. Clonal cultures were established for morphological, molecular, toxicological and ecophysiological investigations to characterize the Finnish populations and compare them to other global A. ostenfeldii isolates. The Finnish isolates exhibited typical morphological features of A. ostenfeldii such as large size, a prominent ventral pore and an orthogonally bent first apical plate. However, unambiguous differentiation from closely related Alexandrium peruvianum was difficult due to considerable variation of sulcal anterior plate shapes. The Finnish strains were genetically distinct from other isolates of the species, but phylogenetic analyses revealed a close relationship to isolates from southern England and an A. peruvianum morphotype from the Spanish Mediterranean. Together these isolates formed a distinct clade which was separated from a clade containing other Northern European, North American and New Zealand populations. Toxin analyses confirmed the presence of the PSP toxins GTX2, GTX3 and STX in both Finnish isolates with GTX3 being the dominant toxin. Total relative PSP toxin contents were moderate, ranging from approximately 6 to 15 fmol cell^?1 at local salinities of 5 and 10 psu, respectively. Spirolides were not detected. Salinity tolerance experiments showed that the Finnish isolates were well adapted to grow at the low salinities of the Baltic Sea. With a salinity range of approximately 6 to 20–25 psu, Baltic populations are physiologically distinct from their marine relatives. Vigorous production of different cyst types in the cultures suggest that cysts may play a crucial role in the survival and retainment of A. ostenfeldii populations in the Baltic Sea.     

Do female pied flycatchers seek extrapair copulations with familiar males? A test of the incomplete knowledge hypothesis

In birds with biparental care, great variation exists in thefrequency of extrapair paternity. Several hypotheses have beenproposed to account for this variation. We tested the incompleteknowledge hypothesis, which states that females are constrainedin their knowledge of male quality and that this influencestheir willingness to engage in extrapair copulations (EPC).By selective removal and release of female pied flycatchersFicedula hypoleuca, we created a situation where females finallysettled with a social mate close to the site where a formersocial mate was breeding. According to the incomplete knowledgehypothesis, this would lower the threshold for females to seekextrapair copulations in cases where their former social matewas of higher quality than the one finally chosen. The hypothesiswas not supported because manipulation of female settlementdid not increase frequency of extrapair paternity, not evenin cases where the female nested close to the previous mateand the current mate apparently was of lower quality becausehe was younger and more dull colored. However, we found that when extrapair paternity did occur, the cuckolder tended tobe a familiar male (i.e., the female's initial social mate).     

Effects of Mesolithic hunter-gatherers on local vegetation in a non-uniform glacio-isostatic land uplift area, northern Sweden

The oldest early Mesolithic settlements found so far (i.e. 8600 b.p.) in the interior of northern Sweden, in the province of Norrbotten, have been discovered through the application of a model simulating glacio-isostatic land uplift. The objective of this study was to investigate, through pollen and charred particle analyses, vegetation composition and the influence of man on vegetation and fire pattern in the vicinity of two of these early settlements. Early Holocene vegetation was characterised by Betula, Hippophaë and Salix-species, but no initial impact by hunter-gatherers on vegetation was detected. Subsequently Betula and Pinus became dominant but abrupt changes in the tree layer followed, Poaceae, Hippophaë and Salix-species increased, and Humulus occurred. These changes, which were synchronous with dates of archaeological findings at the settlements, indicated local vegetation changes caused by man. The relationship between these changes and fire was, however, subtle. Eventually Pinus forests became dominant and human impact on vegetation became less apparent. It is concluded that the impact of early Mesolithic hunter-gatherers on vegetation was detectable, but that their effect on fire pattern was difficult to evaluate. Further, we show that the glacio-isostatic land uplift must be considered in the search for Mesolithic settlements in areas previously covered by the Weichselian Ice, and that the process has influenced the biological archives through re-deposition of material.     

Accumulation of a peptide toxin from the cyanobacterium Oscillatoria agardhii in the freshwater mussel Anadonta cygnea

Swan mussels (Anodonta cygnea) were exposed to a toxic strain of the cyanobacterium Oscillatoria agardhii. Mussels accumulated large amounts of the peptide Oscillatoria toxin which was present in low concentrations within the cyanobacterial cells in the test aquaria (40–60 µg Oscillatoria toxin/1). The toxin concentration in the mussels increased during the experiment and after 15 days of exposure the concentration was 70 ± 2 µg/g freeze dried tissue (mean ± range of values). The highest concentration of the toxin (130 µg/g of freeze dried tissue) was found in the hepatopancreatic tissue. The toxin did not seem to be metabolized in the mussels and they were not killed by the high toxin concentrations within them. After two months in clean water still detectable amounts of toxin were present in the mussels.     

Management implications of the Macquarie Island trophic cascade revisited: a reply to Dowding et al. (2009)

1. The management of non-indigenous species is not without its complications. In Bergstrom et al. 's (2009) study, we demonstrated that feral cats Felis catus on sub-Antarctic Macquarie Island were exerting top-down control on the feral rabbit Oryctolagus cuniculus population, and that the eradication of the cats led to a substantial increase in rabbit numbers and an associated trophic cascade.
2. Dowding et al. (2009) claim our modelling was flawed for various reasons, but primarily that a reduction in the application of the rabbit control agent, Myxoma virus, coinciding with cat removal, was a major driver of rabbit population release.
3. We explore this proposition (as well as others) by examining rates of Myxoma viral release between 1991 and 2006 (with an attenuation factor for the years, 2003–2006) in association with presence/absence of cats against two estimates of rabbit population size. Myxoma viral release was a significant factor in the lower estimates of rabbit population, but the effect was small, and was not significant for higher rabbit population estimates. By contrast, the presence or absence of cats remained highly significant for both estimates.
4. Synthesis and applications. We re-affirm our position that top-down control of rabbit numbers by cats, prior to their eradication, was occurring on Macquarie Island. Nonetheless, we agree with Dowding et al. (2009) that systems with multiple invasive species represent complex situations that require careful scrutiny. Such scrutiny should occur in advance of, during, and following management interventions.     

A CATT Negative Result after Treatment for Human African Trypanosomiasis Is No Indication for Cure

Background

Cure after treatment for human African trypanosomiasis (HAT) is assessed by examination of the cerebrospinal fluid every 6 months, for a total period of 2 years. So far, no markers for cure or treatment failure have been identified in blood. Trypanosome-specific antibodies are detectable in blood by the Card Agglutination Test for Trypanosomiasis (CATT). We studied the value of a normalising, negative post-treatment CATT result in treated Trypanosoma brucei (T.b.) gambiense sleeping sickness patients as a marker of cure.

Methodology/Principal Findings

The CATT/T.b. gambiense was performed on serum of a cohort of 360 T.b. gambiense patients, consisting of 242 primary and 118 retreatment cases. The CATT results during 2 years of post-treatment follow-up were studied in function of cure or treatment failure. At inclusion, sensitivity of CATT was 98% (234/238) in primary cases and only 78% (91/117) in retreatment cases. After treatment, the CATT titre decreased both in cured patients and in patients experiencing treatment failure.

Conclusions/Significance

Though CATT is a good test to detect HAT in primary cases, a normalising or negative CATT result after treatment for HAT does not indicate cure, therefore CATT cannot be used to monitor treatment outcome.     

Molecular phylogenies challenge the classification of Polymastiidae (Porifera,Demospongiae) based on morphology

Polymastiidae Gray, 1867 is a worldwide distributed sponge family, which has a great significance for understanding of the demosponge deep phylogeny since the former order Hadromerida Topsent, 1894 has been recently split based on the molecular evidence and a new separate order has been established for the polymastiids. However, molecular data obtained from Polymastiidae so far are scarce, while the phylogenetic reconstruction based on morphology has faced a deficit of characters along with the vagueness of their states. The present study is a phylogenetic reconstruction of Polymastiidae based on novel data on two molecular markers, cytochrome oxidase subunit I and large subunit ribosomal DNA, obtained from a broad set of species. Monophyly of the family and nonmonophyly of four polymastiid genera are revealed, suggesting a high level of homoplasy of morphological characters, which are therefore not an appropriate base for the natural classification of Polymastiidae. Although the presented phylogenies cannot yet provide an alternative classification scheme, several strongly supported clades, which may be used as reference points in future classification, are recovered and three taxonomic actions are proposed: transfer of one species from Radiella to Polymastia Bowerbank, 1862; transfer of three species from Radiella Schmidt, 1870 to Spinularia Gray, 1867; and the consequent abandonment of Radiella.