Non-indigenous signal crayfish <Emphasis Type="Italic">Pacifastacus leniusculus</Emphasis> are now common in Danish streams: preliminary status for national distribution and protective actions

North American signal crayfish (Pacifastacus leniusculus) are invasive in Europe and pose a serious threat to indigenous European crayfish such as the noble crayfish (Astacus astacus). This is mainly because signal crayfish is the carrier of crayfish plague agent, Aphanomyces astaci, which freshwater crayfish from all other continents are highly susceptible to. Until recently, the distribution of signal crayfish in Danish streams has been considered local and restricted to a small geographical area. Here we present data demonstrating that signal crayfish are now widespread in Denmark, including the largest Danish river, River Gudenå. For one of the rivers where co-existing signal crayfish and indigenous noble crayfish were documented, sensitive molecular tests could not detect the crayfish plague agent Aphanomyces astaci in either species. Hence, it seems that not all signal crayfish are chronic carriers of the disease. For the remaining freshwater systems with the introduced signal crayfish, the infection status is presently unknown. Large areas of the freshwater systems in Denmark also remain unexplored with respect to presence/absence of signal crayfish and noble crayfish. Nevertheless, our preliminary data that covers about 14% of the Danish rivers, strongly suggests that signal crayfish should be considered as a common invader that poses an increased threat to the biota in Danish streams, in particular for the indigenous noble crayfish.     

Effects of Synbiotic2000™ Forte on the Intestinal Motility and Interstitial Cells of Cajal in TBI Mouse Model

The main objective of this study was to investigate the effects of Synbiotic2000? Forte on the intestinal motility and interstitial cells of Cajal (ICC) in traumatic brain injury (TBI) mouse model. Kunming mice were randomly divided into sham operation group (S group), enteral nutrition group with TBI (E group), and Synbiotic2000? Forte group with TBI (P group). The contractile activity of the intestinal smooth muscle, densities and ultrastructure of the ICC, kit protein concentration, weight, and defecation of mice were monitored and analyzed. TBI markedly suppressed contractile activity of the intestinal smooth muscle (P < 0.01), which led to a reduction of defecation (P < 0.01) and weight (P < 0.01). However, application of Synbiotic2000? Forte significantly improved contractile activity of the small intestine (P < 0.01), which may be related to protective effects to the interstitial cells of Cajal, smooth muscle cells, and enteric neurons. TBI impaired ICC networks and densities (P < 0.01), events that were protected by the application of Synbiotic2000? Forte. Synbiotic2000? Forte may attenuate TBI-mediated inhibition of the kit protein pathway. Synbiotic2000? Forte may improve intestinal motility and protect the ICC in the TBI mouse. These findings provide a novel support for the application of Synbiotic2000? Forte in intestinal motility disturbance after TBI.     

Growth and survival of larvae of Thaumetopoea pinivora inside and outside a local outbreak area

1 Outbreaks of herbivorous insects tend to be spatially restricted, possibly because of demographic differences between inside and outside the outbreak area. In some cases, the margin of the outbreak area is distinct, allowing comparisons of adjacent areas that may identify factors leading to such differences in abundance. The northern pine processionary moth Thaumetopoea pinivora presently occurs at outbreak densities within a well‐defined area of approximately 3000 ha on the island of Gotland, south Sweden. We investigated whether cohorts of young larvae (first and second instar) had higher growth rate and survival inside or outside the outbreak area. 2 Group‐feeding appears to promote outbreaks in certain insect groups. Because T. pinivora larvae are highly social, we also compared larval performance between groups of different sizes inside and outside of the outbreak area: ‘small’ (33 eggs/group) and ‘normal’ (100 eggs/group). 3 Averaged over group size, whole colony mortality through the first two instars was two‐fold higher in the non‐outbreak area compared with the outbreak area. Mortality of individual larvae in the surviving colonies, however, did not differ between the two areas. There were only small differences in food quality (toughness, nitrogen content) between the areas, with no detectable effects on larval performance. 4 Larval relative growth rate did not differ between reduced and normal‐sized groups, which is surprising given that growth rate is known to increase with group size in other group‐feeding lepidopterans. 5 Reduced group size negatively affected larval survival, particularly in the outbreak area; by contrast, normal‐sized groups survived equally well in the two areas. Wood ants (Formica spp.) were more common outside the outbreak area, and appeared to be the main cause of colony mortality at low larval density. A different result was observed with regard to per‐capita mortality, which was higher in the outbreak area. We speculate that this could have been due to solitary predators being locally specialized on T. pinivora in the high‐density area.     

Determination of absolute configuration--an overview related to this special issue

Rapid progress in asymmetric synthesis stimulated a further development of methods and techniques for the determination of absolute configuration of chiral molecules. In recent years the direct methods, i.e. X-ray diffraction analysis, circular dichroism (vibrational and electronic), Raman optical activity, optical rotation measurements, as well as indirect methods for relative configuration assignment with the use of NMR spectroscopy or enzymatic transformations, are receiving increasing attention not only by specialists in the field but also by synthetic and structural chemists alike. This paper provides a short overview of the methods currently used, as well as references to contributions collected in this Thematic Issue of Chirality.     

Population based prevalence of high blood pressure among adults in Addis Ababa: uncovering a silent epidemic

Background

We examined whether impaired renal function causes thickening of the aortic valve leaflets in hyperlipidemic apoE-knockout (apoE^-/-) mice, and whether the putative effect on the aortic valves could be prevented by inhibiting the angiotensin-converting enzyme (ACE) with enalapril.

Methods

Thickening of the aortic valve leaflets in apoE^-/- mice was induced by producing mild or moderate chronic renal failure resulting from unilateral nephrectomy (1/2 NX, n = 18) or subtotal nephrectomy (5/6 NX, n = 22), respectively. Additionally, the 5/6 NX mice were randomized to no treatment (n = 8) or enalapril treatment (n = 13). The maximal thickness of each leaflet was measured from histological sections of the aortic roots.

Results

Leaflet thickness was significantly greater in the 5/6 NX mice than in the 1/2 NX mice (P = 0.030) or the unoperated mice (P = 0.003). The 5/6 NX mice treated with enalapril had significantly thinner leaflets than did the untreated 5/6 NX mice (P = 0.014).

Conclusion

Moderate uremia causes thickening of the aortic valves in apoE^-/- mice, which can be attenuated by ACE inhibition. The nephrectomized apoE^-/- mouse constitutes a new model for investigating the mechanisms of uremia-induced aortic valve disease, and also provides an opportunity to study its pharmacologic prevention.     

Stevioside does not cause increased basal insulin secretion or beta-cell desensitization as does the sulphonylurea, glibenclamide: studies in vitro

We have shown that stevioside (SVS) enhances insulin secretion and thus may have a potential role as antihyperglycemic agent in the treatment of type 2 diabetes mellitus. However, whether SVS stimulates basal insulin secretion (BIS) and/or cause desensitization of beta cells like sulphonylureas (SU), e.g. glibenclamide (GB), is not known. To explore and compare the effects of SVS pretreatment with those of GB and glucagon-like peptide-1 (GLP-1), we exposed isolated mouse islets to low or high glucose for 1 h after short-term (2 h) or long-term (24 h) pretreatment with SVS, GB or GLP-1, respectively. BIS at 3.3 or 5.5 mM glucose were not changed after short-term pretreatment with SVS (10(-7) M), while it increased about three folds after pretreatment with GB (10(-7) M). Glucose stimulated insulin secretion (GSIS) (16.7 mM) increased dose-dependently after long-term pretreatment with SVS at concentrations from 10(-7) to 10(-5) M. Pretreatment for 24 h with GB (10(-7) M) increased the subsequent BIS (3.3 mM glucose) (p < 0.001), but decreased GSIS (16.7 mM glucose) (p < 0.001). In contrast SVS (10(-7) M) and GLP-1 (10(-7) M) did not stimulate BIS but both enhanced the subsequent GSIS (16.7 mM glucose) (p < 0.05 and p < 0.05, respectively). While SVS pretreatment increased the intracellular insulin content, GB pretreatment decreased the insulin content. Our study suggests that SVS pretreatment does not cause a stimulation of BIS and does not desensitize beta-cells, i.e. SVS seems to have advantageous characteristics to GB as a potential treatment of type 2 diabetes.     

OpenCMISS: A multi-physics & multi-scale computational infrastructure for the VPH/Physiome project

The VPH/Physiome Project is developing the model encoding standards CellML (cellml.org) and FieldML (fieldml.org) as well as web-accessible model repositories based on these standards (models.physiome.org). Freely available open source computational modelling software is also being developed to solve the partial differential equations described by the models and to visualise results. The OpenCMISS code (opencmiss.org), described here, has been developed by the authors over the last six years to replace the CMISS code that has supported a number of organ system Physiome projects.OpenCMISS is designed to encompass multiple sets of physical equations and to link subcellular and tissue-level biophysical processes into organ-level processes. In the Heart Physiome project, for example, the large deformation mechanics of the myocardial wall need to be coupled to both ventricular flow and embedded coronary flow, and the reaction-diffusion equations that govern the propagation of electrical waves through myocardial tissue need to be coupled with equations that describe the ion channel currents that flow through the cardiac cell membranes.In this paper we discuss the design principles and distributed memory architecture behind the OpenCMISS code. We also discuss the design of the interfaces that link the sets of physical equations across common boundaries (such as fluid-structure coupling), or between spatial fields over the same domain (such as coupled electromechanics), and the concepts behind CellML and FieldML that are embodied in the OpenCMISS data structures. We show how all of these provide a flexible infrastructure for combining models developed across the VPH/Physiome community.     

Using 2,6-dichlorobenzamide (BAM) degrading Aminobacter sp. MSH1 in flow through biofilters—initial adhesion and BAM degradation potentials

Micropollutants in groundwater are given significant attention by water companies and authorities due to an increasing awareness that they might be present even above the legal threshold values. As part of our investigations of the possibility to remove the common groundwater pollutant 2,6-dichlorobenzamide (BAM) by introducing the efficient BAM degrader Aminobacter sp. MSH1 into biologically active sand filters, we investigated if the strain adheres to filters containing various filter materials and if the initial adherence and subsequent degradation of BAM could be optimized. We found that most of the inoculated MSH1 cells adhered fast and that parameters like pH and ionic strength had only a minor influence on the adhesion despite huge influence on cell surface hydrophobicity. At the given growth protocol, the MSH1 strain apparently developed a subpopulation that had lost its ability to adhere to the filter materials, which was supported by attempted reinoculation of non-adhered cells. Analysis by quantitative PCR showed that most cells adhered in the top of the filters and that some of these were lost from the filters during initial operation, while insignificant losses occurred after 1 day of operation. The inoculated filters were found to degrade 2.7 μg/L BAM to below 0.1 μg/L at a 1.1-h residence time with insignificant formation of known degradation products. In conclusion, most filter materials and water types should be feasible for inoculation with the MSH1 strain, while more research into degradation at low concentrations and temperatures is needed before this technology is ready for use at actual waterworks.     

Genetic Diversity and Population Structure Analysis of European Hexaploid Bread Wheat (Triticum aestivum L.) Varieties

Progress in plant breeding is facilitated by accurate information about genetic structure and diversity. Here, Diversity Array Technology (DArT) was used to characterize a population of 94 bread wheat (Triticum aestivum L.) varieties of mainly European origin. In total, 1,849 of 7,000 tested markers were polymorphic and could be used for population structure analysis. Two major subgroups of wheat varieties, GrI and GrII, were identified using the program STRUCTURE, and confirmed by principal component analysis (PCA). These subgroups were largely separated according to origin; GrI comprised varieties from Southern and Eastern Europe, whereas GrII contained mostly modern varieties from Western and Northern Europe. A large proportion of the markers contributing most to the genetic separation of the subgroups were located on chromosome 2D near the Reduced height 8 (Rht8) locus, and PCR-based genotyping suggested that breeding for the Rht8 allele had a major impact on subgroup separation. Consistently, analysis of linkage disequilibrium (LD) suggested that different selective pressures had acted on chromosome 2D in the two subgroups. Our data provides an overview of the allele composition of bread wheat varieties anchored to DArT markers, which will facilitate targeted combination of alleles following DArT-based QTL studies. In addition, the genetic diversity and distance data combined with specific Rht8 genotypes can now be used by breeders to guide selection of crossing parents.