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Design of Striplines for the MAX IV and SOLARIS Storage Rings

MAX IV and SOLARIS are two synchrotron light sources located in Lund and in Krakow, respectively. A stripline is a standard multi-purpose component that is used in many accelerators and consists of one or multiple electrodes. The currents that are induced by the Lorentz contracted fields of the electron beam at the electrodes can be used for beam diagnostics, or one can excite the electrodes in or

Adaptive mechanisms in the hypoxic tumor microenvironment. Functional role of proteoglycans and identification of potential treatment targets

Cancer cells reside in a complex microenvironment comprising stromal cells and immune cells embedded in an extracellular matrix (ECM). Early on in tumor progression, cells reach a critical volume beyond which blood supply is impaired, leading to a decrease in oxygen levels (hypoxia) and nutrient supply. This situation triggers a stress response characterized by a metabolic switch to glycolysis, wh

Body Height and Incident Risk of Venous Thromboembolism : A Cosibling Design

BACKGROUND: Body height has been associated with an increased risk of venous thromboembolism (VTE), but the association can be confounded with shared familial factors (genetic/environmental). A cosibling design is useful for deeper understanding about the relationship between VTE and height.METHODS AND RESULTS: From Swedish national registry databases, we used a corelative design with full sibling

Increased hepatic fatty acid polyunsaturation precedes ectopic lipid deposition in the liver in adaptation to high-fat diets in mice

OBJECTIVE: We monitored hepatic lipid content (HLC) and fatty acid (FA) composition in the context of enhanced lipid handling induced by a metabolic high-fat diet (HFD) challenge and fasting.MATERIALS AND METHODS: Mice received a control diet (10% of kilocalories from fat, N = 14) or an HFD (45% or 60% of kilocalories from fat, N = 10 and N = 16, respectively) for 26 weeks. A subset of five mice r

How Energy Metabolism Supports Cerebral Function : Insights from (13)C Magnetic Resonance Studies In vivo

Cerebral function is associated with exceptionally high metabolic activity, and requires continuous supply of oxygen and nutrients from the blood stream. Since the mid-twentieth century the idea that brain energy metabolism is coupled to neuronal activity has emerged, and a number of studies supported this hypothesis. Moreover, brain energy metabolism was demonstrated to be compartmentalized in ne

Steady-state brain glucose transport kinetics re-evaluated with a four-state conformational model

Glucose supply from blood to brain occurs through facilitative transporter proteins. A near linear relation between brain and plasma glucose has been experimentally determined and described by a reversible model of enzyme kinetics. A conformational four-state exchange model accounting for trans-acceleration and asymmetry of the carrier was included in a recently developed multi-compartmental model

Compartmentalized Cerebral Metabolism of [1,6-(13)C]Glucose Determined by in vivo (13)C NMR Spectroscopy at 14.1 T

Cerebral metabolism is compartmentalized between neurons and glia. Although glial glycolysis is thought to largely sustain the energetic requirements of neurotransmission while oxidative metabolism takes place mainly in neurons, this hypothesis is matter of debate. The compartmentalization of cerebral metabolic fluxes can be determined by (13)C nuclear magnetic resonance (NMR) spectroscopy upon in

In vivo enzymatic activity of acetylCoA synthetase in skeletal muscle revealed by (13)C turnover from hyperpolarized [1-(13)C]acetate to [1-(13)C]acetylcarnitine

BACKGROUND: Acetate metabolism in skeletal muscle is regulated by acetylCoA synthetase (ACS). The main function of ACS is to provide cells with acetylCoA, a key molecule for numerous metabolic pathways including fatty acid and cholesterol synthesis and the Krebs cycle.METHODS: Hyperpolarized [1-(13)C]acetate prepared via dissolution dynamic nuclear polarization was injected intravenously at differ

Glutamatergic and GABAergic energy metabolism measured in the rat brain by (13) C NMR spectroscopy at 14.1 T

Energy metabolism supports both inhibitory and excitatory neurotransmission processes. This study investigated the specific contribution of astrocytic metabolism to γ-aminobutyric acid (GABA) synthesis and inhibitory GABAergic neurotransmission that remained to be ilucidated in vivo. Therefore, we measured (13)C incorporation into brain metabolites by dynamic (13)C nuclear magnetic resonance spect

The C57BL/6J mouse exhibits sporadic congenital portosystemic shunts

C57BL/6 mice are the most widely used strain of laboratory mice. Using in vivo proton Magnetic Resonance Spectroscopy ((1)H MRS), we have repeatedly observed an abnormal neurochemical profile in the brains of both wild-type and genetically modified mice derived from the C57BL/6J strain, consisting of a several fold increase in cerebral glutamine and two fold decrease in myo-inositol. This striking

Caffeine consumption attenuates neurochemical modifications in the hippocampus of streptozotocin-induced diabetic rats

Type 1 diabetes can affect hippocampal function triggering cognitive impairment through unknown mechanisms. Caffeine consumption prevents hippocampal degeneration and memory dysfunction upon different insults and is also known to affect peripheral glucose metabolism. Thus we now characterized glucose transport and the neurochemical profile in the hippocampus of streptozotocin-induced diabetic rats

CB₁ receptor activation inhibits neuronal and astrocytic intermediary metabolism in the rat hippocampus

Cannabinoid CB₁ receptor (CB₁R) activation decreases synaptic GABAergic and glutamatergic transmission and it also controls peripheral metabolism. Here we aimed at testing with ¹³C NMR isotopomer analysis whether CB₁Rs could have a local metabolic role in brain areas having high CB₁R density, such as the hippocampus. We labelled hippocampal slices with the tracers [2-¹³C]acetate, which is oxidized

Metabolic disturbances in diseases with neurological involvement

Degeneration of specific neuronal populations and progressive nervous system dysfunction characterize neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease. These findings are also reported in inherited diseases such as phenylketonuria and glutaric aciduria type I. The involvement of mitochondrial dysfunction in these diseases was reported, elicited by genetic alteratio

Prevalence of factor V gene mutation amongst myocardial infarction patients and healthy controls is higher in Sweden than in other countries

OBJECTIVE: Haemostatic imbalance may be an aetiological factor in the development of acute coronary syndromes. Inherited resistance to activated protein C (APC) is a common disorder associated with hypercoagulability and lifelong risk of venous thrombosis. APC resistance is due to a single mutation in the gene coding for coagulation factor V (FV:Q506). To test the importance of the FV:Q506 mutatio

Activated protein C resistance caused by a common factor V mutation has a single origin

A point mutation (FV:R506Q) in the human coagulation factor V gene is associated with resistance to activated protein C and life-long increased risk of venous thrombosis. The mutation is common in populations of Caucasian origin but virtually absent among other populations. In this study of 140 healthy Swedish volunteers and 110 homozygotes for the FV:R506Q mutation, we determined the allele frequ

Effects of methylphosphonate, a phosphate analogue, on the expression and degradation of the high-affinity phosphate transporter Pho84, in Saccharomyces cerevisiae

In Saccharomyces cerevisiae, the Pho84 high-affinity transport system is the major phosphate transporter activated when the cells experience a limitation in external phosphate. In this study, we have compared the phosphate-responsive mechanism of cells expressing PHO84 with a Deltapho84 strain by use of a phosphate analogue, methylphosphonate, which was judged to be suitable for assessment of phos