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Family and population effects on disease resistance in a reptile

Despite its importance in evolutionary biology, studies of the pattern of disease resistance in natural populations are rare. In this paper, we report patterns of infection of a viral eye disease in juvenile Swedish common lizards (Lacerta vivipara). Females were sampled at random from natural populations immediately prior to parturition with equal exposure of pathogens for all lizards once in cap

Ligustilide induces vasodilatation via inhibiting voltage dependent calcium channel and receptor-mediated Ca(2+) influx and release.

The purpose of the present study was to investigate the effect of ligustilide on vasodilatation in rat mesenteric artery and the mechanisms responsible for it. Isometric tension of rat mesenteric artery rings was recorded by a sensitive myograph system in vitro. The results showed that ligustilide at concentrations more than 10 mu M relaxed potassium chloride (KCl)-preconstricted rat mesenteric ar

Structure and function of the ectomycorrhizal association between Paxillus involutus (Batsch) Fr. and Betula pendula Roth .L. Dynamics of mycorrhiza formation

Detailed examination of the structural and functional integration taking place during mycorrhiza formation necessitates rapid and aseptic synthesis of uniform mycorrhizal structures at well-defined stages of development. A system is described for formation of ectomycorrhizas between Betula pendula Roth. and Paxillus involutus (Batsch) Fr. Small sterile seedlings were placed directly on fungal colo

The nature of hypervelocity stars as inferred from their Galactic trajectories

We have computed the Galactic trajectories of 12 hypervelocity stars (HVSs) under the assumption that they originated in the Galactic Centre. We show that eight of these 12 stars are bound to the Galaxy. We consider the subsequent trajectories of the bound stars to compute their characteristic orbital period, which is 2 Gyr. All eight bound stars are moving away from the centre of the Galaxy, whic

On the intrinsic high temperature calcium oxide-sulfur dioxide reaction using the vacuum thermogravimetric analysis technique

The high temperature CaO/SO2 reaction was studied using four Swedish limestones and one dolomite as sorbents. The measurements were carried out in a vacuum thermogravimetric analysis (TGA) apparatus in order to investigate the intrinsic reaction mechanism. The reaction was found to be fast at the beginning due to the surface reaction, while the subsequent stage was controlled by the product layer

Electrical wiring of Pseudomonas putida and Pseudomonas fluorescens with osmium redox polymers

Two different flexible osmium redox polymers; poly(1-vinylimidazole)(12)-[Os-(4,4'-dimethyl-2,2'-di'pyridyl)(2)Cl-2](2 +/+) (osmium redox polymer I) and poly(vinylpyridine)-[Os-(N,N'-methylated-2,2'-biimidazole)(3)](2+/3+) (osmium redox polymer II) were investigated for their ability to efficiently "wire" Pseudomonas putida ATCC 126633 and Pseudomonas fluorescens (P putida DSM 6521), which are wel

Do anthropogenic transports facilitate stored-product pest moth dispersal? A molecular approach

Stored-product moths cause large economic damage in food-processing industries and storage facilities. Control of indoor pests is currently dealt with locally, and control strategies seldom include different mills or cooperative industries in joint efforts to reduce infestations. In colder climates where conditions hinder flight dispersal of stored-product moths, we hypothesize that human transpor

Effects of Metal-Binding Loop Mutations on Ligand Binding to Calcium- and Integrin-Binding Protein 1. Evolution of the EF-Hand?

Calcium- and integrin-binding protein 1 (CIB1) is a ubiquitous, multifunctional regulatory protein consisting of four helix-loop-helix EF-hand motifs. Neither EF-I nor EF-II binds divalent metal ions; however, EF-III is a mixed Mg2+/Ca2+-binding site, and EF-IV is a higher-affinity Ca2+-specific site. Through the generation of several CIB1 mutant proteins, we have investigated the importance of th

Treatment with tumor necrosis factor blockers is associated with a lower incidence of first cardiovascular events in patients with rheumatoid arthritis

Objective. To investigate the risk of cardiovascular disease (CVD) in patients with rheumatoid arthritis (RA) treated with tumor necrosis factor (TNF) inhibitors, compared to a standard RA population. Methods. Patients were recruited from a regional register, which includes over 90% of patients with RA started on TNF blockers in 1999 or later, and a local community based cohort of RA patients, est

Tumor progression induced by the loss of E-cadherin independent of beta-catenin/Tcf-mediated Wnt signaling

E-cadherin-mediated cell-cell adhesion is frequently lost during the development of malignant epithelial cancers. Employing a transgenic mouse model of beta-cell carcinogenesis (Rip1Tag2) we have previously shown that the loss of E-cadherin is a rate-limiting step in the progression from adenoma to carcinoma. However, the mere loss of cell adhesion may not be sufficient and additional signals are

Ab Initio Density Fitting: Accuracy Assessment of Auxiliary Basis Sets from Cholesky Decompositions

The accuracy of auxiliary basis sets derived by Cholesky decompositions of the electron repulsion integrals is assessed in a series of benchmarks on total ground state energies and dipole moments of a large test set of molecules. The test set includes molecules composed of atoms from the first three rows of the periodic table as well as transition metals. The accuracy of the auxiliary basis sets a

How nitrogen and sulphur addition, and a single drought event affect root phosphatase activity in Phalaris arundinacea

Conservation and restoration of fens and fen meadows often aim to reduce soil nutrients, mainly nitrogen (N) andphosphorus (P). The biogeochemistry of P has received much attention as P-enrichment is expected to negatively impact on species diversity in wetlands. It is known that N, sulphur (S) and hydrological conditions affect the biogeochemistry of P, yet their interactive effects on P-dynamics

Glomerular representation of plant volatiles and sex pheromone components in the antennal lobe of the female Spodoptera littoralis.

We studied the projection patterns of antennal lobe (AL) interneurones sensitive to plant volatiles and female-produced sex pheromone components in the female moth, Spodoptera littoralis. Ten compounds (eight plant-derived compounds and two sex pheromone components) were singly applied to the antenna and, using intracellular recording and staining techniques, the physiological and morphological ch

Oxidation of pyrite grains: A Mossbauer spectroscopy and mineral magnetism study

Fe2+ in pyrite is found in a low-spin d(6) configuration, a necessary condition for diamagnetic and semi-conducting properties of material. The semi-conducting property of pyrite has been studied since the time when pyrite was used as a rectifier in early radios. Pyrite posses the highest possible crystal field stabilisation energy and offers a better altemative as solar material compared to Si- b

Diamond-Blackfan anemia: erythropoiesis lost in translation.

Diamond-Blackfan anemia (DBA) is a congenital erythroid aplasia that usually presents as macrocytic anemia during infancy. Linkage analysis suggests that at least 4 genes are associated with DBA of which 2 have been identified so far. The known DBA genes encode the ribosomal proteins S19 and S24 accounting for 25% and 2% of the patients, respectively. Herein, we review possible links between ribos

TCID50 determination by an immuno dot blot assay as exemplified in a study of storage conditions of infectious pancreatic necrosis virus

Some cell lines are difficult to grow in confluent monolayers and, therefore, the plaque assay cannot be applied since plaques may be hard to distinguish from other blank areas of the cell monolayers. To avoid this problem a rapid and sensitive immuno dot blot TCID50 method was developed using antibodies against virus antigens to detect infection and virus production. An alternative statistical me