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Short-term carbon input increases microbial nitrogen demand, but not microbial nitrogen mining, in a set of boreal forest soils

Rising carbon dioxide (CO2) concentrations and temperatures are expected to stimulate plant productivity and ecosystem C sequestration, but these effects require a concurrent increase in N availability for plants. Plants might indirectly promote N availability as they release organic C into the soil (e.g., by root exudation) that can increase microbial soil organic matter (SOM) decomposition (“pri

Local and trans-Atlantic chemostratigraphic significance of new δ13Ccarb data from the Sandbian and Katian Stages (Middle–Upper Ordovician) of the Oslo region, Norway

Late Sandbian to early Katian δ13Ccarb chemostratigraphy has in Norway been described in only two previous reports that dealt with two geographically rather widely separated areas, namely the Oslo-Asker district and the Nes-Hamar district. No data have been available from the Ordovician outcrop areas between these districts that could help clarify the partly unclear regional stratigraphic relation

From discovery to justification : Outline of an ideal research program in empirical psychology

The gold standard for an empirical science is the replicability of its research results. But the estimated average replicability rate of key-effects that top-tier psychology journals report falls between 36 and 39% (objective vs. subjective rate; Open Science Collaboration, 2015). So the standard mode of applying null-hypothesis significance testing (NHST) fails to adequately separate stable from

The Harmonized Parabolic Synthesis Methodology for Hardware Efficient Function Generation with Full Error Control

The Harmonized Parabolic Synthesis methodology is a further development of the Parabolic Synthesis methodology for approximation of unary functions such as trigonometric functions, logarithms and the square root with moderate accuracy for ASIC implementation. These functions are extensively used in computer graphics, communication systems and many other application areas. For these high-speed appl

Abnormalities at different levels of the hypothalamic-pituitary-adrenocortical axis early after stroke

BACKGROUND AND PURPOSE: Hypercortisolism is common in stroke patients. The aim of this study was to investigate possible disturbances at different sites within the hypothalamic-pituitary-adrenal axis. We also studied possible associations between hypercortisolism and clinical manifestations of brain dysfunction.METHODS: Patients with an acute ischemic stroke (n = 16; mean +/- SD age, 71 +/- 11 yea

Glycerol as a marker for post-traumatic membrane phospholipid degradation in rat brain

Degradation of membrane phospholipids (PLs) is a well known phenomenon in acute brain injuries and is thought to underlie the disturbance of vital cellular membrane functions. In the present study glycerol, an end product of PL degradation, was examined in brain interstitial fluid as a marker of PL breakdown following experimental traumatic brain injury (TBI) using microdialysis. TBI was induced i

Hypoxanthine, uric acid and allantoin as indicators of in vivo free radical reactions. Description of a HPLC method and human brain microdialysis data

A practical one-step high performance liquid chromatography (HPLC) method was developed for the simultaneous determination of hypoxanthine, uric acid and allantoin in small (4 microL) microdialysis samples. The rationale for this work was the current interest in hypoxanthine as a marker for energy perturbation in hypoxia/ ischemia, in uric acid as an endogenous antioxidant, and in allantoin as a m

Fibroblasts potentiate melanoma cells in vitro invasiveness induced by UV-irradiated keratinocytes

Melanoma represents a malignant disease with steadily increasing incidence. UV-irradiation is a recognized key factor in melanoma initiation. Therefore, the efficient prevention of UV tissue damage bears a critical potential for melanoma prevention. In this study, we tested the effect of UV irradiation of normal keratinocytes and their consequent interaction with normal and cancer-associated fibro

Intracerebral microdialysis in neurointensive care : the use of urea as an endogenous reference compound

OBJECT: When evaluating the results of intracerebral microdialysis, the in vivo performance of the microdialysis probe must be considered, because this determines the fraction of the interstitial concentration obtained in the microdialysis samples. The in vivo performance is dependent on several factors, for example, the interstitial compartment's diffusion characteristics, which may vary during t

Active listing and more consultations in primary care are associated with reduced hospitalisation in a Swedish population

Background: Healthcare systems are complex networks where relationships affect outcomes. The importance of primary care increases while health care acknowledges multimorbidity, the impact of combinations of different diseases in one person. Active listing and consultations in primary care could be used as proxies of the relationships between patients and primary care. Our objective was to study ho

Epidemiology of primary systemic vasculitis in children : a population-based study from southern Sweden

Objectives: To estimate the annual incidence rate of paediatric primary systemic vasculitis (PSV) in a defined geographical area in southern Sweden. Methods: Potential cases of PSV [IgA vasculitis (IgAV, Henoch–Schönlein purpura), Kawasaki disease (KD), granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), eosinophilic granulomatosis with polyangiitis (EGPA), polyarteritis nodosa

Paradoxical increase in neuronal DNA fragmentation after neuroprotective free radical scavenger treatment in experimental traumatic brain injury

The mechanisms and role of nerve cell death after traumatic brain injury (TBI) are not fully understood. The authors investigated the effect of pretreatment with the oxygen free radical spin trap alpha-phenyl-N-tert-butyl-nitrone (PBN) on the number of neurons undergoing apoptosis after TBI in rats. Apoptotic cells were identified by the TUNEL method combined with the nuclear stain, Hoechst 33258,

Monitoring of reactive oxygen species production after traumatic brain injury in rats with microdialysis and the 4-hydroxybenzoic acid trapping method

The detection of reactive oxygen species (ROS) after traumatic brain injury (TBI) is based on indirect methods due to the high reactivity and short half-life of ROS in biological tissue. The commonly used salicylate trapping method has several disadvantages making it unsuitable for human use. We have evaluated 4-hydroxybenzoic acid (4-HBA) together with microdialysis (MD) in the rat as an alternat

Curating social image : Experimental evidence on the value of actions and selfies

We manipulate the information subjects can share on the web concerning socially sensitive actions (public good contribution) and visibility (selfie) to determine the effect on social image, as captured by the price subjects demand for publication. Our novel design incorporates aspects of social media interaction including limited anonymity and the possibility to manipulate published information in

Dendritic cell migration to skin-draining lymph nodes is controlled by dermatan sulfate and determines adaptive immunity magnitude

For full activation of naïve adaptive lymphocytes in skin-draining lymph nodes (LNs), presentation of peptide:MHC complexes by LN-resident and skin-derived dendritic cells (DCs) that encountered antigens (Ags) is an absolute prerequisite. To get to the nearest draining LN upon intradermal immunization, DCs need to migrate from the infection site to the afferent lymphatics, which can only be reache

Effects of the nitrone radical scavengers PBN and S-PBN on in vivo trapping of reactive oxygen species after traumatic brain injury in rats

In previous studies, the authors showed that the nitrone radical scavenger alpha-phenyl-N- tert -butyl nitrone (PBN) and its sulfo-derivative, 2-sulfo-phenyl-N- tert -butyl nitrone (S-PBN), attenuated cognitive disturbance and reduced tissue damage after traumatic brain injury (TBI) in rats. In the current study, the production of reactive oxygen species (ROS) after TBI was monitored with microdia

Cyclooxygenase-2, prostaglandin synthases, and prostaglandin H2 metabolism in traumatic brain injury in the rat

Inflammatory mediators are important in traumatic brain injury (TBI). The objective of the present study was to investigate the expression of cyclooxygenase-2 (COX-2), prostaglandin E (PGE) and PGD synthases, and PGH2 metabolism in two rat models of TBI. Fluid percussion injury (FPI) resulted in bilateral induction of COX-2 mRNA in the dentate gyri and the cortex, whereas controlled cortical contu

Early cerebral hyperglycolysis after subarachnoid haemorrhage correlates with favourable outcome

BACKGROUND: Intracerebral microdialysis (MD) was applied in patients with severe subarachnoid haemorrhage treated in a neurosurgical intensive care unit in order to explore their cerebral energy metabolism.METHOD: Brain MD fluid levels of glucose, lactate and pyruvate were measured for 3 to 12 days in 20 patients and 2,635 hourly samples were analysed. The MD data were related to computerized tomo

Low and high circulating cortisol levels predict mortality and cognitive dysfunction early after stroke

OBJECTIVE: Elevated cortisol levels are associated with confusion and poor outcome after stroke. Dehydroepiandrosterone sulphate (DS), the most abundant adrenal androgen may act as an anti-glucocorticoid. An altered regulation of these steroids may affect numerous brain functions, including neuronal survival. The purpose of this study was to investigate serum cortisol and DS levels and the cortiso

Anterior and Posterior ERP Rhyming Effects in 3- to 5-year-old Children

During early literacy skills development, rhyming is an important indicator of the phonological precursors required forreading. To determine if neural signatures of rhyming are apparent in early childhood, we recorded event-relatedpotentials (ERPs) from 3- to 5-year-old, preliterate children (N = 62) in an auditory prime-target nonword rhymingparadigm (e.g., bly-gry, blane-vox). Overall, nonrhyminDuring early literacy skills development, rhyming is an important indicator of the phonological precursors required for reading. To determine if neural signatures of rhyming are apparent in early childhood, we recorded event-related potentials (ERPs) from 3- to 5-year-old, preliterate children (N = 62) in an auditory prime-target nonword rhyming paradigm (e.g., bly-gry, blane-vox). Overall, nonrhy