Xenon improves neurologic outcome and reduces secondary injury following trauma in an in vivo model of traumatic brain injury

Objectives: To determine the neuroprotective efficacy of the inert gas xenon following traumatic brain injury and to determine whether application of xenon has a clinically relevant therapeutic time window. Design: Controlled animal study. Setting: University research laboratory. Subjects: Male C57BL/6N mice (n = 196). Interventions: Seventy-five percent xenon, 50% xenon, or 30% xenon, with 25% oxygen (balance nitrogen) treatment following mechanical brain lesion by controlled cortical impact. Measurements and Main Results: Outcome following trauma was measured using 1) functional neurologic outcome score, 2) histological measurement of contusion volume, and 3) analysis of locomotor function and gait. Our study shows that xenon treatment improves outcome following traumatic brain injury. Neurologic outcome scores were significantly (p < 0.05) better in xenon-treated groups in the early phase (24 hr) and up to 4 days after injury. Contusion volume was significantly (p < 0.05) reduced in the xenon-treated groups. Xenon treatment significantly (p < 0.05) reduced contusion volume when xenon was given 15 minutes after injury or when treatment was delayed 1 or 3 hours after injury. Neurologic outcome was significantly (p < 0.05) improved when xenon treatment was given 15 minutes or 1 hour after injury. Improvements in locomotor function (p < 0.05) were observed in the xenon-treated group, 1 month after trauma. Conclusions: These results show for the first time that xenon improves neurologic outcome and reduces contusion volume following traumatic brain injury in mice. In this model, xenon application has a therapeutic time window of up to at least 3 hours. These findings support the idea that xenon may be of benefit as a neuroprotective treatment in patients with brain trauma

Real examples of surface reconstructions determined by direct methods

In this work the modulus sum function is briefly introduced and its applicability to the automated interpretation of projections of reconstructed surfaces shown. The selected real examples have been arranged according to the interpretation complexity of the respective two-dimensional Patterson maps and correspond to the most common types of surface reconstructions represented by: (i) a shift of the surface atoms from their ideal positions. This type of reconstruction is often found on (001) semiconductor surfaces and its most characteristic structural feature is the pairing of neighbouring surface atoms forming dimers, e.g., the In0.04Ga0.96As(001)-p(4 × 2) reconstructed surface. (ii) Different atom types occupying the surface sites. This type of reconstruction can be induced by both the adsorption of deposited atoms onto the surface, e.g. Sb/Ge(113)-c(2 × 2), or a new structural arrangement of the substrate caused by the adsorption of external molecules onto the surface, e.g. C60/Au(110)-p(6 × 5) reconstructed surface

A2A adenosine receptor-driven cAMP signaling in olfactory bulb astrocytes is unaffected in experimental autoimmune encephalomyelitis

IntroductionThe cyclic nucleotide cyclic adenosine monophosphate (cAMP) is a ubiquitous second messenger, which is known to play an important anti-inflammatory role. Astrocytes in the central nervous system (CNS) can modulate inflammation but little is known about the significance of cAMP in their function.MethodsWe investigated cAMP dynamics in mouse olfactory bulb astrocytes in brain slices prepared from healthy and experimental autoimmune encephalomyelitis (EAE) mice.ResultsThe purinergic receptor ligands adenosine and adenosine triphosphate (ATP) both induced transient increases in cAMP in astrocytes expressing the genetically encoded cAMP sensor Flamindo2. The A2A receptor antagonist ZM241385 inhibited the responses. Similar transient increases in astrocytic cAMP occurred when olfactory receptor neurons were stimulated electrically, resulting in ATP release from the stimulated axons that increased cAMP, again via A2A receptors. Notably, A2A-mediated responses to ATP and adenosine were not different in EAE mice as compared to healthy mice.DiscussionOur results indicate that ATP, synaptically released by afferent axons in the olfactory bulb, is degraded to adenosine that acts on A2A receptors in astrocytes, thereby increasing the cytosolic cAMP concentration. However, this pathway is not altered in the olfactory bulb of EAE mice

Interdomain Interactions Control Ca2+-Dependent Potentiation in the Cation Channel TRPV4

Several Ca2+-permeable channels, including the non-selective cation channel TRPV4, are subject to Ca2+-dependent facilitation. Although it has been clearly demonstrated in functional experiments that calmodulin (CaM) binding to intracellular domains of TRP channels is involved in this process, the molecular mechanism remains elusive. In this study, we provide experimental evidence for a comprehensive molecular model that explains Ca2+-dependent facilitation of TRPV4. In the resting state, an intracellular domain from the channel N terminus forms an autoinhibitory complex with a C-terminal domain that includes a high-affinity CaM binding site. CaM binding, secondary to rises in intracellular Ca2+, displaces the N-terminal domain which may then form a homologous interaction with an identical domain from a second subunit. This represents a novel potentiation mechanism that may also be relevant in other Ca2+-permeable channels

Neue Batteriesysteme zwischen Forschung und Anwendung

Der Vortrag gibt einen Überblick über aktuell verfügbare und eingesetzte Speichertechnologien. Exemplarisch werden aktuelle Entwicklungstrends und Forschungsarbeiten zu stationären Batterietechnologien vorgestellt. Ausgewählte Anwendungsbeispiele von stationären Energiespeichern unterschiedlicher Technologien und Größen auf unterschiedlichen Netzebenen werden im Detail diskutiert. Der Vortrag schließt mit systemtechnischen Entwicklungen und Perspektiven für stationäre Stromspeicher

A novel Sb induced reconstruction of the (113) surface of Ge

Sb induces on Ge(113) a c(2x2) reconstruction in which Sb breaks one Ge-Ge bond and occupies an interstitial site, in contrast to Sb adsorption on other Si or Ge surfaces. Sb saturates the three dangling bonds per unit cell of the (113) surface inducing a large strain which is released by occupation of the interstitial site. Two neighboring Sb at interstitial sites form a dimer. The structure has been determined by x-ray diffraction, applying direct methods, and ab initio density-functional-theory calculations. The adsorption geometry and the high binding energy lead one to expect that Sb cannot be used as a surfactant for the growth of Si/Ge layers on the (113) surface