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The mutational mechanism underlying the striking diversity in MHC (major histocompatibility complex) genes in vertebrates is still controversial. In order to evaluate the role of inter- and intragenic recombination in MHC gene diversification, we examined patterns of nucleotide polymorphism across an exon/intron boundary in a sample of 31 MHC class IIB sequences of three-spined stickleback (Gaster

Housing rats in an enriched environment after focal brain ischemia improves functional outcome without changes in infarct volume, suggesting neuroplastic changes outside the lesion. In this study, permanent occlusion of the middle cerebral artery was followed by housing in an enriched or a standard environment. Nerve growth factor-induced gene A and glucocorticoid receptor messenger RNA expression

Two-step steam pretreatment of softwood was investigated with the aim of improving the enzymatic digestibility for ethanol production. In the first step, softwood was impregnated with SO2 and steam pretreated at different severities. The first step was performed at low severity to hydrolyze the hemicellulose and release the sugars into the solution. The combination of time and temperature that yie

The transcription factor Rex has been implicated in regulation of the expression of genes important for fermentative growth and for growth under conditions of low oxygen tension in several Gram-positive bacteria. Rex senses the redox poise of the cell through changes in the NADH/NAD(+) ratio. The crystal structures of two essentially identical Rex proteins, from Thermus aquaticus and T. thermophil

We have previously shown that the number of satellite cells is lower in old than young men and women. The aim of this study was to further explore the effects of aging on the regenerative potential of skeletal muscle in 16 young and 26 old men and women with comparable physical activity level (young, 25 +/- 4 years; old, 75 +/- 4 years). Mean and minimum telomere lengths were determined using Sout

The ionization sensor is an electrical probe for diagnostics in internal combustion engines. Laser-induced fluorescence (LIF) imaging of fuel, hydroxyl (OH), and nitric oxide (NO) distributions has been employed to extend our knowledge about the governing processes leading to its signal. By monitoring the flame propagation in quiescent and turbulent mixtures, the cycle-to-cycle variations in the e

We describe a fixed parameter algorithm for computing the minimum weight triangulation (MWT) of a simple polygon with (n - k) vertices on the perimeter and k hole vertices in the interior, that is, for a total of n vertices. Our algorithm is based on cutting out empty triangles (that is, triangles not containing any holes) from the polygon and processing the parts or the rest of the polygon recurs

Steady linear gravity waves of small amplitude travelling on a current of constant vorticity are found. For negative vorticity we show the appearance of internal waves and vortices, wherein the particle trajectories are not any more closed ellipses. For positive vorticity the situation resembles that of Stokes waves, but for large vorticity the trajectories are affected.

The REXEBIS is an Electron Beam Ion Source (EBIS) developed particularly for charge breeding of rare and short-lived isotopes produced at ISOLDE for the REX-ISOLDE post accelerator. Bunches of singly charged radioactive ions are injected into the EBIS and charge bred to a charge-to-mass ratio of approximately 114 and thereafter extracted and injected into a short LINAC. This novel concept, employi

Brain expression of transferrin (Tf) and transthyretin (TTR) mRNA has been demonstrated in different species, TTR being found only in the choroid plexus. We report here that both these mRNAs are also expressed in the meninges. In vitro studies have shown that Tf secretion by the rat choroid plexus is stimulated by 5-hydroxytryptamine (5-HT) while sympathetic nerves regulate different transport fun

Bone marrow stromal cells (BMSC) have gained increased attention because of their multipotency and adult stem cell character. They have been shown to differentiate into other cell types of the mesenchymal lineage and also into non-mesenchymal cells. The exact identity of the original cells, which are isolated from bone marrow by their selective adherence to plastic, remains unknown to date. We hav

Background: Activated fibroblasts, which have previously been obtained from bronchoalveolar lavage fluid (BALF), are proposed to be important cells in the fibrotic processes of asthma and scleroderma (SSc). We have studied the motility for BALF derived fibroblasts in patients with SSc that may explain the presence of these cells in the airway lumen. Furthermore, we have compared phenotypic alterat

We present a laser lithography technique based on lift-off, for fast and flexible prototyping of micro and nanoelectromechanical systems (MEMS/NEMS). The technique is based on direct laser writing on substrates coated with a resist bi-layer consisting of polymethyl methacrylate (PMMA) on lift-off resist (LOR). Laser writing melts and evaporates the PMMA exposing the LOR. Oxygen ashing removes PMMA

We consider the problem of computing a minimum weight pseudo-triangulation of a set S of n points in the plane. We first present an O(nlogn)-time algorithm that produces a pseudo-triangulation of weight O(wt(M(S))logn) which is shown to be asymptotically worst-case optimal, i.e., there exists a point set S for which every pseudo-triangulation has weight Omega(wt(M(S))logn), where wt(M(S)) is the w

We applied 27k spotted cDNA microarray slides to assess gene expression profiles in 26 samples from 24 patients with synovial sarcomas (SS). The data were analyzed in relation to histopathologic type, cytogenetic aberrations, gene fusion type and development of distant metastases. Supervised analysis based on gene fusion type in 12 SS with SS18/SSXI and 9 with SS18/SSX2 revealed significant differ

Identification and characterization of membrane proteins is of increasing importance in modern proteomic studies. It is of central interest to have access to methods that combine efficient solubilization with enrichment of proteins and intact protein complexes. Separation methods have been developed based on nondenaturing detergent extraction of yeast mitochondrial membrane proteins followed by en

Transposon mutagenesis provides a fundamental tool for functional genomics. Here we present a non-species-specific, combined enhancer detection and binary expression system based on the transposable element piggyBac: For the different components of this insertional mutagenesis system, we used widely applicable transposons and distinguishable broad-range transformation markers, which should enable

Experimental studies have shown that remodelling of the atrial myocardium is linked to the occurrence and perpetuation of atrial fibrillation (AF). Clinical evidence, however, is insufficient. We recorded monophasic action potentials (MAP) during AF from one to three sites in the right atrium in seven patients with chronic AF (CAF) and in 11 patients with paroxysmal AF (PAF). The fibrillatory (FF)

Characterization of the count-rate performance of scintillation cameras should include not only the specification of count losses. At high count rates, there is also an image distortion due to the mispositioning of pile-up events. In this paper a simple and clinically relevant procedure to quantify this distortion is presented. The images of a square uniform technetium-99m phantom at high and low

BACKGROUND: The purpose of this study was to evaluate if propofol has 5-HT3 antagonistic effects. Ipecacuanha is known to release serotonin (5-HT) in the gastrointestinal tract and therefore ipecacuanha syrup was used to induce nausea and vomiting. The 5-HT3 antagonist ondansetron was used as a control substance. METHOD: Ten healthy male volunteers (20-37 years) were studied on three occasions and