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Characterisation of an ATP receptor mediating mitogenesis in vascular smooth muscle cells

Adenosine triphosphate (ATP), a co-transmitter in sympathetic nerves and released from platelets, has recently been shown to stimulate growth of vascular smooth muscle cells. It might therefore contribute to the development of vascular hypertrophy seen in hypertension and atherosclerosis. We aimed at characterising the receptor mediating this mitogenic effect in rat aorta smooth muscle cells. The

Model cellulose films exposed to H-insolens glucoside hydrolase family 45 endo-cellulase - the effect of the carbohydrate-binding module

The effects of enzyme structure and activity on the degradation of model cellulose substrates were investigated by ellipsometry for the cellulase Humicola insolens GH45. The inactive variant D10N was found to adsorb at the cellulose surface but also to be incorporated into the cellulose films to an extent that depended on pH. For the native protein, the initial adsorption monitored for the inactiv

Distribution of different fiber types in human skeletal muscles: why is there a difference within a fascicle?

The proportions of different fiber types (type 1 and type 2) on the borders of fascicles are shown to differ from the proportions internally. This finding is based on the analysis of a total of 245 fascicles from whole cross-sections of the vastus lateralis muscle from 13 men, aged from 26-80 years. Generally, the difference is more marked in the young than in the old. It is argued that the causes

Metal chelate affinity precipitation: purification of (His)6-tagged lactate dehydrogenase using poly(vinylimidazole-co-N-isopropylacrylamide)copolymers

Affinity precipitation is a highly selective bioseparation method, which has been successfully used in the purification of various enzymes/proteins. The separation of (His)6-tagged lactate dehydrogenase ((His)6-LDH) was carried through affinity precipitation technique using thermoresponsive copolymer poly(vinylimidazole-co-N-isopropyl-acrylamide) (poly(VI-NIPAM)). Nearly quantitative recovery of (

High frequency characterization of a GaInAs/InP electronic waveguide T-branch switch

We report comprehensive microwave measurements on a T-branch switch; a GaInAs/InP electron waveguide based structure. The study includes a small signal model of the device where limitations of high frequency operation are discussed. An example of large signal operation where the nonlinearity of the device is exploited by operating the T-branch switch as a frequency multiplier is demonstrated.

Theoretical and experimental evaluation of phase-dispersion effects caused by brain motion in diffusion and perfusion MR imaging

We investigated intravoxel phase dispersion caused by pulsatile brain motion in diffusion spin-echo pulse sequences. Mathematical models were used to describe the spatial and temporal velocity distributions of human brain motion. The spatial distribution of brain-tissue velocity introduces a phase spread over one voxel, leading to signal loss. This signal loss was estimated theoretically, and effe

Shaping Stable Periodic Motions of Inertia Wheel Pendulum: Theory And Experiment

We consider an underactuated two-link robot called the inertia wheel pendulum. The system consists of a free planar rotational pendulum and a symmetric disk attached to its end, which is directly controlled by a DC-motor. The goal is to create stable oscillations of the pendulum, which is not directly actuated. We exploit a recently proposed feedback-control design strategy based on motion plannin

Titanium-hydrogen peroxide interaction: model studies of the influence of the inflammatory response on titanium implants

In vitro studies of titanium and TiO2 as well as other metals were carried out to investigate the role of these metals in the inflammatory response through the Fenton reaction. The TiOOH matrix formed traps the superoxide radical, so that no or very small amounts of free hydroxyl radicals are produced. Ellipsometry and spin trapping with spectrophotometry and electron spin resonance (ESR) were use

Development of an H-TDMA for long-term unattended measurement of the hygroscopic properties of atmospheric aerosol particles

A new hygroscopic tandem differential mobility analyzer (H-TDMA) has been constructed at Lund University within the frameworks of the EU FP6 Infrastructure Project EUSAAR (www.eusaar.org). The aim of this coordinated H-TDMA development is to design and evaluate a new generation of H-TDMAs that are capable of conducting long term measurements of the hygroscopic growth and state of mixing of sub-mic

Do coupling exciton and oscillation of electron-hole pair exist in neutral and charged pi-dimeric quinquethiophenes?

Optical physical properties of neutral and charged quinquethiophene monomer, and neutral and cationic pi-dimeric quinquethiophenes were investigated with density functional theory as well as the two dimensional (2D) site (transition density matrix) and three dimensional (3D) cube (transition density and charge difference density) representations, stimulated by the recent experimental report [T. Sa

Resistant starch formation in temperature treated potato starches varying in amylose/amylopectin ratio

Two genetically modified potato starches derived from the same mother line (64%, 1% and 23% amylose, respectively) were used to study the bioavailability after various heat treatments. The conditions for the treatments were of minor importance for resistant starch (RS) formation and hydrolysis results, as compared to the proportion of amylose. A high amylose content gave lower hydrolysis index (HI

Quantum Chemical Study of the Influence of Anchor-Cum-Spacer Groups on Femtosecond Electron Transfer Times in Dye-Sensitized Semiconductor Nanocrystals

Electronic properties of dye-sensitized semiconductor nanocrystals, consisting of perylene (Pe) chromophores attached to 2 nm TiO2 nanocrystals via different anchor-cum-spacer groups, have been studied theoretically using density functional theory (DFT) cluster calculations. Approximate effective electronic coupling strengths for the heterogeneous electron-transfer interaction have been extracted

An esterolytic imprinted polymer prepared via a silica-supported transition state analogue

In this work we describe a new preparation method for an esterolytic imprinted polymer with catalytic sites on the surface. A template was prepared by immobilizing a transition state analogue (phosphoramidic acid derivative) of an esterolytic reaction within porous silica particles. Polymerization within the pores was carried out using 4-vinylimidazole as a functional monomer and divinylbenzene as

Association of a microsatellite in FASL to type II diabetes and of the FAS-670G > A genotype to insulin resistance

Type II diabetes is caused by a failure of the pancreatic beta-cells to compensate for insulin resistance leading to hyperglycaemia. There is evidence for an essential role of an increased beta-cell apoptosis in type II diabetes. High glucose concentrations induce IL-1 beta production in human beta-cells, Fas expression and concomitant apoptosis owing to a constitutive expression of FasL. FASL and

Variants of the interleukin-1 receptor antagonist gene are associated with fat mass in men

Context: Immune functions seem to have connections to variations in body fat mass. Studies of knockout mice indicate that endogenous interleukin (IL)-1 can suppress mature-onset obesity. Objective: To systematically investigate our hypotheses that single- nucleotide polymorphisms (SNPs) and/or haplotypes variants in the IL-1 gene system are associated with fat mass. Subjects: The Gothenburg osteop

Glued-in rods for timber structures - An experimental study of softening behaviour

A test method to obtain the strength and the fracture characteristics of the bond of glued-in rods for timber structures is presented. Test results from a series of tests using the proposed method are also given. The test method makes it possible to record the complete stress-displacement response of small test specimens. This response includes the softening behaviour after peak stress,i.e. the de