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Hypofunction of the N-methyl-D-aspartate receptor (NMDAR) has been implicated as a possible mechanism underlying cognitive deficits and aberrant neuronal dynamics in schizophrenia. To test this hypothesis, we first administered a sub-anaesthetic dose of S-ketamine (0.006 mg/kg/min) or saline in a single-blind crossover design in 14 participants while magnetoencephalographic data were recorded during a visual task. In addition, magnetoencephalographic data were obtained in a sample of unmedicated first-episode psychosis patients (n = 10) and in patients with chronic schizophrenia (n = 16) to allow for comparisons of neuronal dynamics in clinical populations versus NMDAR hypofunctioning. Magnetoencephalographic data were analysed at source-level in the 1–90 Hz frequency range in occipital and thalamic regions of interest. In addition, directed functional connectivity analysis was performed using Granger causality and feedback and feedforward activity was investigated using a directed asymmetry index. Psychopathology was assessed with the Positive and Negative Syndrome Scale. Acute ketamine administration in healthy volunteers led to similar effects on cognition and psychopathology as observed in first-episode and chronic schizophrenia patients. However, the effects of ketamine on high-frequency oscillations and their connectivity profile were not consistent with these observations. Ketamine increased amplitude and frequency of gamma-power (63–80 Hz) in occipital regions and upregulated low frequency (5–28 Hz) activity. Moreover, ketamine disrupted feedforward and feedback signalling at high and low frequencies leading to hypo- and hyper-connectivity in thalamo-cortical networks. In contrast, first-episode and chronic schizophrenia patients showed a different pattern of magnetoencephalographic activity, characterized by decreased task-induced high-gamma band oscillations and predominantly increased feedforward/feedback-mediated Granger causality connectivity. Accordingly, the current data have implications for theories of cognitive dysfunctions and circuit impairments in the disorder, suggesting that acute NMDAR hypofunction does not recreate alterations in neural oscillations during visual processing observed in schizophrenia.
Background: The pro-inflammatory status of the elderly triggers most of the age-related diseases such as cancer and atherosclerosis. Atherosclerosis, the leading cause world wide of morbidity and death, is an inflammatory disease influenced by life-style and genetic host factors. Stimuli such as oxLDL or microbial ligands have been proposed to trigger inflammation leading to atherosclerosis. It has recently been shown that oxLDL activates immune cells via the Toll-like receptor (TLR) 4/6 complex. Several common single nucleotide polymorphisms (SNPs) of the TLR system have been associated with atherosclerosis. To investigate the role of TLR-6 we analyzed the association of the TLR-6 SNP Pro249Ser with atherogenesis.
Results: Genotyping of two independent groups with CAD, as well as of healthy controls revealed a significant association of the homozygous genotype with a reduced risk for atherosclerosis (odds ratio: 0.69, 95% CI 0.51-0.95, P = 0.02). In addition, we found a trend towards an association with the risk of restenosis after transluminal coronary angioplasty (odds ratio: 0.53, 95% CI 0.24-1.16, P = 0.12). In addition, first evidence is presented that the frequency of this protective genotype increases in a healthy population with age. Taken together, our results define a role for TLR-6 and its genetic variations in modulating the inflammatory response leading to atherosclerosis.
Conclusions: These results may lead to a better risk stratification, and potentially to an improved prophylactic treatment of high-risk populations. Furthermore, the protective effect of this polymorphism may lead to an increase of this genotype in the healthy elderly and may therefore be a novel genetic marker for the well-being during aging.
Correction to: Scientific Reports https://doi.org/10.1038/srep21848, published online 22 February 2016
This Article contains an error. Among the studied species, the orangutan was erroneously specified as Bornean orangutan Pongo pygmaeus. In fact, the studied individual was a Sumatran orangutan Pongo abelii.
The purpose of this phase III clinical trial was to compare two different extracellular contrast agents, 1.0 M gadobutrol and 0.5 M gadopentate dimeglumine, for magnetic resonance imaging (MRI) in patients with known or suspected focal renal lesions. Using a multicenter, single-blind, interindividual, randomized study design, both contrast agents were compared in a total of 471 patients regarding their diagnostic accuracy, sensitivity, and specificity to correctly classify focal lesions of the kidney. To test for noninferiority the diagnostic accuracy rates for both contrast agents were compared with CT results based on a blinded reading. The average diagnostic accuracy across the three blinded readers (‘average reader’) was 83.7% for gadobutrol and 87.3% for gadopentate dimeglumine. The increase in accuracy from precontrast to combined precontrast and postcontrast MRI was 8.0% for gadobutrol and 6.9% for gadopentate dimeglumine. Sensitivity of the average reader was 85.2% for gadobutrol and 88.7% for gadopentate dimeglumine. Specificity of the average reader was 82.1% for gadobutrol and 86.1% for gadopentate dimeglumine. In conclusion, this study documents evidence for the noninferiority of a single i.v. bolus injection of 1.0 M gadobutrol compared with 0.5 M gadopentate dimeglumine in the diagnostic assessment of renal lesions with CE-MRI.
Cryptochromes are a ubiquitous group of blue-light absorbing flavoproteins that in the mammalian retina have an important role in the circadian clock. In birds, cryptochrome 1a (Cry1a), localized in the UV/violet-sensitive S1 cone photoreceptors, is proposed to be the retinal receptor molecule of the light-dependent magnetic compass. The retinal localization of mammalian Cry1, homologue to avian Cry1a, is unknown and it is open whether mammalian Cry1 is also involved in magnetic field sensing. To constrain the possible role of retinal Cry1, we immunohistochemically analysed 90 mammalian species across 48 families in 16 orders, using an antiserum against the Cry1 C-terminus that in birds labels only the photo-activated conformation. In the Carnivora families Canidae, Mustelidae and Ursidae and in some Primates, Cry1 was consistently labeled in the outer segment of the shortwave-sensitive S1 cones. This finding would be compatible with a magnetoreceptive function of Cry1 in these taxa. In all other taxa, Cry1 was not detected by the antiserum that likely also in mammals labels the photo-activated conformation, although Western blots showed Cry1 in mouse retinal cell nuclei. We speculate that in the mouse and the other negative-tested mammals Cry1 is involved in circadian functions as a non-light-responsive protein.
Elliptic flow from nuclear collisions is a hadronic observable sensitive to the early stages of system evolution. We report first results on elliptic flow of charged particles at midrapidity in Au+Au collisions at sqrt[sNN] = 130 GeV using the STAR Time Projection Chamber at the Relativistic Heavy Ion Collider. The elliptic flow signal, v2, averaged over transverse momentum, reaches values of about 6% for relatively peripheral collisions and decreases for the more central collisions. This can be interpreted as the observation of a higher degree of thermalization than at lower collision energies. Pseudorapidity and transverse momentum dependence of elliptic flow are also presented.
Elliptic flow from nuclear collisions is a hadronic observable sensitive to the early stages of system evolution. We report first results on elliptic flow of charged particles at midrapidity in Au+Au collisions at sqrt(s_NN)=130 GeV using the STAR TPC at RHIC. The elliptic flow signal, v_2, averaged over transverse momentum, reaches values of about 6% for relatively peripheral collisions and decreases for the more central collisions. This can be interpreted as the observation of a higher degree of thermalization than at lower collision energies. Pseudorapidity and transverse momentum dependence of elliptic flow are also presented.
First measurement of 𝚲+c production down to 𝑝T = 0 in pp and p–Pb collisions at √𝑠NN = 5.02 TeV
(2023)
The production of prompt Λ+c baryons has been measured at midrapidity in the transverse momentum interval 0<pT<1 GeV/c for the first time, in pp and p-Pb collisions at a centre-of-mass energy per nucleon-nucleon collision sNN−−−√=5.02 TeV. The measurement was performed in the decay channel Λ+c→pK0S by applying new decay reconstruction techniques using a Kalman-Filter vertexing algorithm and adopting a machine-learning approach for the candidate selection. The pT-integrated Λ+c production cross sections in both collision systems were determined and used along with the measured yields in Pb-Pb collisions to compute the pT-integrated nuclear modification factors RpPb and RAA of Λ+c baryons, which are compared to model calculations that consider nuclear modification of the parton distribution functions. The Λ+c/D0 baryon-to-meson yield ratio is reported for pp and p-Pb collisions. Comparisons with models that include modified hadronisation processes are presented, and the implications of the results on the understanding of charm hadronisation in hadronic collisions are discussed. A significant (3.7σ) modification of the mean transverse momentum of Λ+c baryons is seen in p-Pb collisions with respect to pp collisions, while the pT-integrated Λ+c/D0 yield ratio was found to be consistent between the two collision systems within the uncertainties.
First measurement of 𝚲+c production down to 𝑝T = 0 in pp and p–Pb collisions at √𝑠NN = 5.02 TeV
(2023)
The production of prompt Λ+c baryons has been measured at midrapidity in the transverse momentum interval 0<pT<1 GeV/c for the first time, in pp and p-Pb collisions at a centre-of-mass energy per nucleon-nucleon collision sNN−−−√=5.02 TeV. The measurement was performed in the decay channel Λ+c→pK0S by applying new decay reconstruction techniques using a Kalman-Filter vertexing algorithm and adopting a machine-learning approach for the candidate selection. The pT-integrated Λ+c production cross sections in both collision systems were determined and used along with the measured yields in Pb-Pb collisions to compute the pT-integrated nuclear modification factors RpPb and RAA of Λ+c baryons, which are compared to model calculations that consider nuclear modification of the parton distribution functions. The Λ+c/D0 baryon-to-meson yield ratio is reported for pp and p-Pb collisions. Comparisons with models that include modified hadronisation processes are presented, and the implications of the results on the understanding of charm hadronisation in hadronic collisions are discussed. A significant (3.7σ) modification of the mean transverse momentum of Λ+c baryons is seen in p-Pb collisions with respect to pp collisions, while the pT-integrated Λ+c/D0 yield ratio was found to be consistent between the two collision systems within the uncertainties.
Borstgrasrasen, ein prägender Bestandteil der Kulturlandschaft im Schwarzwald, sind in starkem Wandel begriffen, der in erster Linie von Änderungen der Landnutzung abhängt. Um die funktionellen Zusammenhänge in den Borstgrasrasen abbilden zu können, werden die dort vorkommenden Arten zu funktionellen Pflanzentypen gruppiert. Für diese Klassifikation der Arten werden Merkmale herangezogen, die funktionell mit der Reaktion der Arten auf unterschiedlich intensive Beweidung oder Pflege in Zusammenhang stehen. Zum einen wird an ausgewählten Merkmalen, die vor Ort gemessen wurden, überprüft, wie sie bei ausgewählten Arten innerhalb und zwischen Beständen und schließlich auch zwischen den Arten variieren, um deren Eignung für eine Klassifikation zu prüfen. Zum anderen werden Eigenschaften für eine Reihe von Arten aus der Merkmals-Datenbank LEDA abgefragt und zur Ableitung von funktionellen Pflanzentypen (PFTs) mittels numerischer Klassifikation verwendet. Es zeigt sich, dass einige Eigenschaften wie die spezifische Blattfläche (SLA) eine gute Eignung für die Differenzierung von Arten und Beständen haben, da sie nur bei einigen Arten und zudem wenig plastisch auf unterschiedlich intensive Beweidung reagieren. Andere Merkmale, wie das C/N-Verhältnis der Blätter, variieren sehr stark innerhalb einiger Arten und eignen sich somit weniger für eine Klassifikation. Diese ergibt 17 PFTs, die zunächst nach der Lebensform unterschieden werden und dann insbesondere nach den Kriterien Anordnung der Blätter, spezifische Blattfläche und Blattfläche weiter untergliedert werden Einige PFTs zeigen klar unterschiedliche Deckungswerte in verschiedenen Typen von Borstgrasrasen. Andere tragen nicht zur Differenzierung der Rasen bei, da sie in den unterschiedlichen Borstgrasrasen durchgehend Matrixarten enthalten oder überall nur spärlich auftreten. Eine grafische Auswertung nach dem ordinalen LHS-Ansatz (je eine Achse für SLA, Wuchshöhe und Samenmasse) zeigt eine einigermaßen klare Differenzierung der meisten der o. g. Typen von Borstgrasrasen. So sind beide Ansätze, PFT und LHS, geeignet, um eine Zuordnung des Nutzungstyps der Borstgrasrasen vorzunehmen.