Maternal origin of nucleated erythrocytes in peripheral venous blood of pregnant women

We studied the origin of nucleated red blood cells (NRBC) in peripheral venous blood samples from 40 pregnant women carrying a male fetus, using a technique that allows direct chromosomal analysis by in situ hybridisation on immunologically and morphologically classified cells. Samples from ten nulligravid women were studied as controls. NRBC were enriched by negative magnetic activated cell sorting (miniMACS) using anti-CD45 monoclonal antibody. NRBC were detected by alkaline phosphatase anti-alkaline phosphatase immunostaining using a monoclonal anti-glycophorin A antibody. The origin of the NRBC was determined by fluorescence in situ hybridisation using X and Y specific probes. NRBC were found in 37 of the 40 pregnant women at a range of 1 to 230 per 20 ml of venous blood and in 6 of the 10 controls at a range of 1 to 3 per 20 ml of venous blood. All NRBC detected in the pregnant women were evidently of maternal origin, and in the pregnant women the number of NRBC was significantly higher (P < 0.05) than in the controls. Pregnancy per se seems to induce the appearance of maternal NRBC in the circulation, and it cannot therefore be assumed that NRBC isolated from the maternal blood are of fetal origin on the basis of morphology alone. Discrimination of fetal NRBC must occur for prenatal diagnosis of fetal genetic disorders.     

Compositional turnover and variation in Eemian pollen sequences in Europe

Vegetation History and Archaeobotany - The Eemian interglacial represents a natural experiment on how past vegetation with negligible human impact responded to amplified temperature changes...     

Structural Basis for Complement Evasion by Lyme Disease Pathogen Borrelia burgdorferi

Borrelia burgdorferi spirochetes that cause Lyme borreliosis survive for a long time in human serum because they successfully evade the complement system, an important arm of innate immunity. The outer surface protein E (OspE) of B. burgdorferi is needed for this because it recruits complement regulator factor H (FH) onto the bacterial surface to evade complement-mediated cell lysis. To understand this process at the molecular level, we used a structural approach. First, we solved the solution structure of OspE by NMR, revealing a fold that has not been seen before in proteins involved in complement regulation. Next, we solved the x-ray structure of the complex between OspE and the FH C-terminal domains 19 and 20 (FH19-20) at 2.83 Å resolution. The structure shows that OspE binds FH19-20 in a way similar to, but not identical with, that used by endothelial cells to bind FH via glycosaminoglycans. The observed interaction of OspE with FH19-20 allows the full function of FH in down-regulation of complement activation on the bacteria. This reveals the molecular basis for how B. burgdorferi evades innate immunity and suggests how OspE could be used as a potential vaccine antigen.     

Sensitive and specific detection of microRNAs by northern blot analysis using LNA-modified oligonucleotide probes

We describe here a new method for highly efficient detection of microRNAs by northern blot analysis using LNA (locked nucleic acid)-modified oligonucleotides. In order to exploit the improved hybridization properties of LNA with their target RNA molecules, we designed several LNA-modified oligonucleotide probes for detection of different microRNAs in animals and plants. By modifying DNA oligonucleotides with LNAs using a design, in which every third nucleotide position was substituted by LNA, we could use the probes in northern blot analysis employing standard end-labelling techniques and hybridization conditions. The sensitivity in detecting mature microRNAs by northern blots was increased by at least 10-fold compared to DNA probes, while simultaneously being highly specific, as demonstrated by the use of different single and double mismatched LNA probes. Besides being highly efficient as northern probes, the same LNA-modified oligonucleotide probes would also be useful for miRNA in situ hybridization and miRNA expression profiling by LNA oligonucleotide microarrays.     

The Local Complement Activation on Vascular Bed of Patients with Systemic Sclerosis: A Hypothesis-Generating Study

ObjectiveThe role of complement system in the pathogenesis of systemic sclerosis (SSc) has been debated during the last decade but an evident implication in this disease has never been found. We carried out an explorative study on SSc patients to evaluate the expression of soluble and local C5b-9 complement complex and its relation with a complement regulator, the Membrane Cofactor Protein (MCP, CD46) on skin vascular bed as target distinctive of SSc disease. We also analyzed two polymorphic variants in the complement activation gene cluster involving the MCP region.MethodsC5b-9 plasma levels of SSc patients and healthy subjects were analyzed by ELISA assay. Archival skin biopsies of SSc patients and controls were subjected to immunofluorescence analysis to detect C5b-9 and MCP on vascular endothelial cells. The expression of MCP was validated by immunoblot analysis with specific antibody. Polymorphic variants in the MCP gene promoter were tested by a quantitative PCR technique-based allelic discrimination method.ResultsEven though circulating levels of C5b-9 did not differ between SSc and controls, C5b-9 deposition was detected in skin biopsies of SSc patients but not in healthy subjects. MCP was significantly lower in skin vessels of SSc patients than in healthy controls and was associated with the over-expression of two polymorphic variants in the MCP gene promoter, which has been related to more aggressive phenotypes in other immune-mediated diseases.ConclusionsOur results firsty document the local complement activation with an abnormal expression of MCP in skin vessels of SSc patients, suggesting that a subset of SSc patients might be exposed to more severe organ complications and clinical evolution due to abnormal local complement activation.     

The good bad wolf—wolf evaluation reveals the roots of the Finnish wolf conflict

This article focuses on the roots of the Finnish wolf conflict by using stakeholder evaluations of the wolf as a tool. The recent growth of the wolf population has highlighted stakeholders’ contradictory objectives and revealed a conflict between the two main stakeholders, conservationists and hunters, in wolf management. The question of hunting emerges as the core of the conflict. The negative evaluation of the wolf by hunters reflects a competitive situation, which is typical of the historical development of wolf management in Finland. In areas with the most abundant wolf populations, hunters view the wolf most negatively. This study clearly demonstrates that the Finnish wolf conflict is rooted in the values of modern society and carries a long historical, practical and ecological background in which humans and wolves compete over resources, mainly the moose. The conflict between hunters and conservationists in wolf management is connected to the appreciation of moose as game and stems from competition between humans and wolves over their prey and the historical presence or absence of the wolf.     

On-line high performance liquid chromatography measurements of extracellular metabolites in an aerobic batch yeast (<Emphasis Type="Italic">Saccharomyces cerevisiae</Emphasis>) culture

We constructed a bioprocess environment enabling automatic sampling from a bioreactor combined with a compact on-line high performance liquid chromatography (HPLC) unit. This setup allowed us to measure extracellular glucose, ethanol, glycerol, and acetate concentrations automatically at 5 min intervals during the cultivation. This environment also provides mechanical measurement of the optical density (OD) of cells and enables us to collect and store (−35°C) samples for further off-line analyses. Among the available devices, the performance of the sampling-analysis unit is by far the best with regard to speed and number of analytes. Both the sampling and analysis phases are easily controlled by software; thus, providing a unique environment to perform various bioprocess activity tasks, whether they would be cell line screening or optimisation of conditions for growth and productivity. Complex research set-ups can be created and continuous automated measurements empower long-term cultivations with a time series. We provide evidence for the applicability of this environment by performing three comparable batch cultivations with Saccharomyces cerevisiae yeast and show that both the on-line sampling and analysis modes produce reliable data for further use in the monitoring and controlling of bioprocesses. On-line data provided new insight into the dynamics of the diauxic shift during aerobic glucose batch cultivation. When cell growth and carbon dioxide production ceased for the first time during the diauxic shift, acetate accumulation and consumption of the remaining glucose below 0.15 g/L continued to occur for 1 h. At the same time, glycerol and ethanol began to be consumed. Samples were also collected during cultivation for later analysis of intracellular metabolites and to collect more valuable information about metabolism.