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Oxygen modulates contractile responses to potassium and prostaglandin F2 alpha in human pial arteries

Oxygen may modulate cerebrovascular resistance, but its direct influence on human pial arteries is unknown. We have investigated the effects of varying oxygen tension (73, 30 and 8 kPa) in depolarized (potassium) and receptor stimulated (prostaglandin F2 alpha) isolated human pial arteries. Control responses were obtained at an oxygen tension of 30 kPa. Contractions induced by prostaglandin F2 alp

Variability and seasonality of North Atlantic climate during the early Holocene: evidence from Faroe Island lake sediments

Based on their position in relation to major ocean currents, palaeoclimatic archives in the Faroe Islands are expected to be sensitive recorders of variations in North Atlantic circulation. The multiproxy analysis ( magnetic susceptibility, total carbon, nitrogen and sulphur, biogenic silica, grains > 255 mu m) of a lacustrine record with both winter and summer climate indicators illustrates the v

Nitrous oxide reduces inspired oxygen fraction but does not compromise circulation and oxygenation during hemodilution in pigs

BACKGROUND: The use of nitrous oxide (N2O) during hemodilution has been questioned. Nitrous oxide reduces the inspired oxygen fraction (F1O2), depresses myocardial function and may reduce cardiac output (CO) and systemic oxygen delivery (DO2SY). The aim of this study was to evaluate the importance of the effects of nitrous oxide on systemic and myocardial circulation and oxygenation during extreme

Gluon-Spin Contribution to the Proton Spin from the Double-Helicity Asymmetry in Inclusive pi(0) Production in Polarized p plus p Collisions at root s=200 GeV

The double helicity asymmetry in neutral pion production for p(T) = 1 to 12 GeV/c was measured with the PHENIX experiment to access the gluon-spin contribution, Delta G, to the proton spin. Measured asymmetries are consistent with zero, and at a theory scale of mu 2 = 4 GeV2 a next to leading order QCD analysis gives Delta G([0.02,0.3]) = 0.2, with a constraint of -0.7 < Delta G([0.02,0.3]) < 0.5

Toll-like receptors in cellular subsets of human tonsil T cells: altered expression during recurrent tonsillitis

Background: The palatine tonsils have a pivotal role in immunological detection of airborne and ingested antigens like bacteria and viruses. They have recently been demonstrated to express Toll-like receptors ( TLRs), known to recognize molecular structures on such microbes and activate innate immune responses. Their activation might also provide a link between innate and adaptive immunity. In the

Endotoxin- and D-galactosamine-induced liver injury improved by the administration of Lactobacillus, Bifidobacterium and blueberry

Background. D-galactosamine together with lipopolysaccharide can lead to a pronounced secretion by Kupffer cells of pro-inflammatory mediators, which have been shown to be early and important mediators of liver injury. Probiotics and dietary supplementation with fruit or vegetable extracts with high content of antioxidants, such as blueberry, could be beneficial in protecting against hepatotoxicit

Diffusion of nutrients molecules and model drug carriers through mucin layer investigated by magnetic resonance imaging with chemical shift resolution

Magnetic resonance imaging (MRI) with chemical shift resolution is a recent extension of MRI and it provides information about species resolved molecular transport on the macroscopic scale in complex systems. In this contribution, we show that by using this novel method, one can predict the behavior of drug and food molecules when they are in contact with the mucosal layer in the gastrointestinal

Separating the chance effect from other diversity effects in the functioning of plant communities

The effect of plant species diversity on productivity and competitive ability was studied in an experiment carried out simultaneously in five European countries: Czech Republic (CZ), the Netherlands (NL), Sweden (SE), Spain (SP), and United Kingdom (UK). The aim was to separate the 'chance' or 'sampling effect' (increasing the number of sown species increases the probability that a species able 't

Cognition- and anxiety-related behavior, synaptophysin and MAP2 immunoreactivity in the adult rat treated with a single course of antenatal betamethasone

We investigated the effects of a single course of antenatal betamethasone on cognition- and anxiety-related behavior and synaptophysin and microtubule-associated protein 2 (MAP2) immunoreactivity in the adult rat hippocampus. On d 20 of gestation, pregnant rats were injected with either 1) 170 mu g/kg body weight of betamethasone ("clinically equivalent dose," equivalent to 12 mg twice, 24 h apart

Small habitat islands are inferior breeding habitats but are used by some great tits - competition or ignorance?

Great tit breeding performance in small habitat islands in an agricultural landscape was compared to that in large deciduous woods. Clutch size was similar in both habitats, but more nestlings starved and fledgling weight was lower in the small habitat islands. The area of wooded habitat in the territories of tits breeding in the small habitat islands was less than what is common to encounter in '

Antimicrobial peptides derived from growth factors

Growth factors, comprising diverse protein and peptide families, are involved in a multitude of developmental processes, including embryogenesis, angiogenesis, and wound healing. Here we show that peptides derived from HB-EGF, amphiregulin, hepatocyte growth factor, PDGF-A and PDGF-B, as well as various FGFs are antimicrobial, demonstrating a previously unknown activity of growth factor-derived pe

Seasonal variation in serum concentrations of reproductive hormones and urinary excretion of 6-sulfatoxymelatonin in men living north and south of the Arctic Circle: a longitudinal study.

bjective Seasonal variation in photoperiod or temperature may influence human reproductive biology. The present study evaluated whether seasonal changes occurred in the levels of reproductive hormones and the major melatonin metabolite, 6-sulfatoxymelatonin (aMT6s), in populations exposed to extreme variation in photoperiod and temperature. Design Two separate cohorts of Norwegian men were recruit

Solid-phase diffusion mechanism for GaAs nanowire growth

Controllable production of nanometre-sized structures is an important field of research, and synthesis of one-dimensional objects, such as nanowires, is a rapidly expanding area with numerous applications, for example, in electronics, photonics, biology and medicine. Nanoscale electronic devices created inside nanowires, such as p-n junctions(1), were reported ten years ago. More recently, hetero-

Identification of cutting errors in precision hard turning process

During past 10 years, the availability of polycrystalline cubic boron nitride (PCBN) tools has made application of hard turning increase remarkably in a range of industrial areas, especially in automotive, roller bearing and hydraulic industry. Among the applications of CBN cutting tools, precision hard turning attracts great interests since its environmentally friendly and flexibility, which ulti

Aqueous two-phase systems with a liquid protein (bovine serum albumin) phase for partitioning of enzymes

New aqueous liquid-liquid two-phase systems based on bovine serum albumin and sodium thiocyanate in combination with either poly(vinyl alcohol) or poly(ethylene glycol) were investigated. Phase diagrams are presented. Lactate dehydrogenase and some mitochondrial enzymes were partitioned in the systems. All the phase components used influenced, either positively or negatively, the activity of lacta

Quantitative measurement of carotid atherosclerosis in relation to levels of von Willebrand factor and fibrinolytic variables in plasma - a 2-year follow-up study

Background It has been proposed that the mechanism of action of the new risk factors for myocardial infarction and stroke, von Willebrand factor (vWF), tissue plasminogen activator (tPA) and tissue plasminogen activator inhibitor-1 (PAI-1) could possibly be mediated via a primary effect on atherogenesis but there is little data to substantiate this. Design A prospective single-centre cohort study

The Hidden Normative Process Behind the Construction of European Migration Policies

This paper examines how legal science can provide a new perspective and instrument of analysis for understanding how action is produced by legal rules in a given system. By treating legal rules as a factor of explanation in perceiving political action, the authors aim to use them as a scientific perspective that will reflect whether there is a normative determination to generate harmonised legisla