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Objective To explore the association of both plasma vitamin D and K concentrations with all-cause mortality, cardiovascular mortality, and cardiovascular events in the general population. Methods We studied 4742 participants of the Prevention of REnal and Vascular ENd-Stage Disease (PREVEND) Study. At baseline, vitamin D and K status was determined by measurement of 25-hydroxyvitamin D [25(OH)D] and dephosphorylated uncarboxylated matrix Gla protein (dp-ucMGP), respectively. Patients were categorized into: 25(OH)D 75 nmol/L and dp-ucMGP Results Mean age was 52.6 ± 11.9 years and 2513 (53%) were female. During a median of 14.2 year follow-up, 620 participants died of which 142 were due to cardiovascular causes. Combined low vitamin D and K status was present in 970 participants (20%) and was associated with a greater risk of all-cause mortality compared to high vitamin D and high vitamin K status group (n = 1424) after adjusting for potential confounders: hazard ratio 1.46 (95% confidence intervals 1.12–1.90). We observed similar trends, albeit non-significant for cardiovascular mortality, and cardiovascular events: 1.42 (0.79–2.55), 1.28 (0.93–1.77), respectively. Conclusions Combined low vitamin D and K status are associated with increased all-cause mortality risk and possibly with cardiovascular mortality and cardiovascular events compared with adequate vitamin D and K status. Future studies should investigate the effect of combined vitamin D and K supplementation on clinical outcomes.

For radioligands without a reference region, the Lassen plot can be used to estimate receptor occupancy by an exogenous drug ([Formula: see text]). However, the Lassen plot is not well-suited for spatial variation in [Formula: see text]. To overcome this limitation, we introduce a Lassen plot filter, i.e. a Lassen plot applied to local neighborhoods in PET images. Image data were simulated with regional variation in [Formula: see text], [Formula: see text], both, or neither and analyzed using the change in binding potential ([Formula: see text]), the conventional Lassen plot, and the Lassen plot filter at the region of interest (ROI) and voxel level. All methods were also applied to a human [11C]flumazenil occupancy study using PF-06372865. This combination of a non-selective radioligand and selective drug should lead to varying [Formula: see text]provided the distribution of subtypes varies spatially. In contrast with [Formula: see text] and the conventional Lassen plot, ROI-level and voxel-level Lassen plot filter estimates remained unbiased in the presence of regional variation in [Formula: see text] or [Formula: see text]. In the [11C]flumazenil data-set, [Formula: see text] was shown to vary regionally in accordance with the distribution of binding sites for [11C]flumazenil and PF-06372865. We demonstrate that a local-neighborhood Lassen plot filter provides robust and unbiased estimates of [Formula: see text] and [Formula: see text] without the need for any user intervention.

H 2 , the smallest and most abundant molecule in the universe, has a perfectly symmetric ground state. What does it take to break this symmetry? We found that the inversion symmetry can be broken by absorption of a linearly polarized photon, which itself has inversion symmetry. In particular, the emission of a photoelectron with subsequent dissociation of the remaining H + 2 fragment shows no symmetry with respect to the ionic H + and neutral H atomic fragments. This lack of symmetry results from the entanglement between symmetric and antisymmetric H + 2 states that is caused by autoionization. The mechanisms behind this symmetry breaking are general for all molecules.

We report on the size-dependent interaction of carbon monoxide molecules with hydrogen covered vanadium clusters containing between 5 and 20 atoms. Structural information on these hydrogen covered vanadium clusters and their complexes with CO is obtained from infrared multiple photon dissociation spectroscopy, complemented with density functional theory calculations for the V-5 to V-9 cluster sizes. The non-dissociative or dissociative binding of CO on the metal clusters is detected by the presence or absence of the nu(CO) stretching band in the infrared spectra. It is found that the CO molecule dissociates on bare vanadium clusters, while it adsorbs intact on all saturated hydrogen covered V-5-20(+) clusters, with the distinctive exceptions of V-5(+), V-9(+), V-11(+), and V-19(+). We show that dissociative chemisorption is prevented when the potential binding sites of atomic C and O atoms are blocked by H atoms.

Rationale: The dopaminergic system has been implicated in the pathogenesis and treatment of a variety of neuropsychiatric disorders. It has been shown that information on endogenous dopamine (DA) release can be obtained noninvasively by combining positron emission tomography with a dopaminergic challenge. This approach is based on the assumption that an injected radiolabeled ligand competes with the neurotransmitter for the same receptor. Increases in DA release will therefore result in a decreased binding of the radioligand.Objectives: We investigated the effect of the DA reuptake blocker methylphenidate (MP) on the binding of the D-2 receptor ligand [C-11]-raclopride (RAC). Methods: The effect of a 0.25 mg/kg intravenous dose of MP was studied in six healthy volunteers. RAC was administered as a bolus followed by constant infusion, and subjective effects were assessed using verbal rating scales. Results: Control scans without MP administration showed that the mean RAC binding reached stable values approximately 30 min after start of the infusion. MP administration induced a 24% decrease in RAC binding in the total striatum. Correlations were found between the MP-induced change in euphoria and the percent change in binding potential (Delta BP) in the dorsal striatum and between baseline anxiety and Delta BP in the dorsal and middle striatum. We also found a negative correlation between baseline BP in the dorsal striatum and change in euphoria. Conclusions: Our results comply with previous findings, indicating the feasibility of the bolus infusion design combined with a relatively low MP dose to study dopaminergic (dys)function.

Rationale : Previously, we have shown that the atypical antipsychotics clozapine and risperidone, unlike haloperidol, decreased the firing rate of substantia nigra reticulata (SNR) neurons. As the SNR receives substantial input from the striatum, an area where motoric side-effects of antipsychotics are thought to be mediated, the SNR might be an interesting brain structure with regard to motor side-effects. Objective: : The newly developed atypical antipsychotic olanzapine was studied for its effects on the firing rate of SNR cells. In addition, to gain insight in the implications of our experimental setup for clinical use, responses upon clozapine, olanzapine and haloperidol were studied after chronic treatment. Methods: In chloralhydrate-anaesthetized male Wistar rats, extracellular recordings were made from SNR neurons upon intravenously (IV) administered cumulative doses of the antipsychotics. Naive rats and rats that were subcutaneously (SC) injected for 21 days with an antipsychotic were used. Results: Olanzapine (50-100 mg/kg; IV), significantly inhibited the firing rate of the SNR neurons. Upon 21 days of treatment with a daily SC injection of 20 mg/kg clozapine, the challenge on day 22 with cumulative injections of clozapine (200-6400 mg/kg; IV) significantly inhibited the firing rate of the SNR neurons. Olanzapine (50-1600 mg/kg; IV) also significantly inhibited the SNR activity when pretreated with olanzapine in an SC administered dose of 1 mg/kg, but not 5 mg/kg. Haloperidol (12.5-800 mu g/kg; IV) did not significantly affect the SNR activity in rats pretreated with SC administered 0.5 mg/kg haloperidol. Conclusions: Upon acute and chronic administration of clozapine and olanzapine versus haloperidol, differential effects on SNR neuronal firing could be obtained. The experimental setup seem to be valid for further studies into the mechanism of action of typical versus (relatively low doses of) atypical antipsychotics. The implications of the inhibitory effect of atypical antipsychotics on the SNR firing rate are presently unknown, but could be associated with the lower propensity to induced motoric side-effects. On the other hand, the SNR activity might also reflect non-motoric activity possibly related to negative symptoms.

Rationale : Previously, we have shown that the atypical antipsychotics clozapine and risperidone, unlike haloperidol, decreased the firing rate of substantia nigra reticulata (SNR) neurons. As the SNR receives substantial input from the striatum, an area where motoric side-effects of antipsychotics are thought to be mediated, the SNR might be an interesting brain structure with regard to motor side-effects. Objective: : The newly developed atypical antipsychotic olanzapine was studied for its effects on the firing rate of SNR cells. In addition, to gain insight in the implications of our experimental setup for clinical use, responses upon clozapine, olanzapine and haloperidol were studied after chronic treatment. Methods: In chloralhydrate-anaesthetized male Wistar rats, extracellular recordings were made from SNR neurons upon intravenously (IV) administered cumulative doses of the antipsychotics. Naive rats and rats that were subcutaneously (SC) injected for 21 days with an antipsychotic were used. Results: Olanzapine (50-100 mg/kg; IV), significantly inhibited the firing rate of the SNR neurons. Upon 21 days of treatment with a daily SC injection of 20 mg/kg clozapine, the challenge on day 22 with cumulative injections of clozapine (200-6400 mg/kg; IV) significantly inhibited the firing rate of the SNR neurons. Olanzapine (50-1600 mg/kg; IV) also significantly inhibited the SNR activity when pretreated with olanzapine in an SC administered dose of 1 mg/kg, but not 5 mg/kg. Haloperidol (12.5-800 mu g/kg; IV) did not significantly affect the SNR activity in rats pretreated with SC administered 0.5 mg/kg haloperidol. Conclusions: Upon acute and chronic administration of clozapine and olanzapine versus haloperidol, differential effects on SNR neuronal firing could be obtained. The experimental setup seem to be valid for further studies into the mechanism of action of typical versus (relatively low doses of) atypical antipsychotics. The implications of the inhibitory effect of atypical antipsychotics on the SNR firing rate are presently unknown, but could be associated with the lower propensity to induced motoric side-effects. On the other hand, the SNR activity might also reflect non-motoric activity possibly related to negative symptoms.

The development of a synthetic approach to the novel pyrrolo[2,1-b][1,3]benzothiazepine and its derivatives and their biological evaluation as potential antipsychotic drugs are described. In binding studies these compounds proved to be potent 5-HT2, D-2, and D-3 receptor ligands. The more potent benzothiazepine (+/-)-3b was resolved into its enantiomers by using HPLC techniques. In vitro testing confirmed that (-)-3b is a more potent D-2 receptor ligand, maintaining high affinity for 5-HT2 receptors. In contrast, the (+)-3b enantiomer presents a 35 times higher affinity for 5-HT2 than for dopamine D-2 receptors with a similar dopamine D-1 receptor affinity to that of (-)-3b. Overall, (+)-3b shows an "atypical" neuroleptic binding profile, while (-)-3b has a more "classical" profile. Furthermore pharmacological and biochemical testing displayed that the novel benzothiazepine (+/-)-3b is able to increase the extracellular levels bf dopamine in the rat striatum and causes a dose-related suppression of apomorphine-induced locomotor activity. At low doses (+/-)-3b does not induce catalepsy, showing atypical antipsychotic properties similar to those of olanzapine. These heterocyclic compouds represent new leads for the development of novel antipsychotic drugs with atypical properties.

We employed a fully optimized shadow wave function in combination with variational Monte Carlo techniques to investigate the properties of HD molecules and molecular ortho-deuterium (o-D-2) in bulk solid para-hydrogen (p-H-2). Calculations were performed for different concentrations of impurities ranging from about 1% to 25% at the equilibrium density for the para-hydrogen crystal. By computing the excess energy both for clustered and isolated impurities, we tried to determine a limit for the solubility of HD and o-D-2 in p-H-2.

We present an analytical model based on the time-dependent WKB approximation to reproduce the photoionization spectra of an H2 molecule in the autoionization region. We explore the nondissociative channel, which is the major contribution after one-photon absorption, and we focus on the features arising in the energy differential spectra due to the interference between the direct and the autoionization pathways. These features depend on both the timescale of the electronic decay of the autoionizing state and the time evolution of the vibrational wavepacket created in this state. With full ab initio calculations and with a one-dimensional approach that only takes into account the nuclear wavepacket associated to the few relevant electronic states we compare the ground state, the autoionizing state, and the background continuum electronic states. Finally, we illustrate how these features transform from molecular-like to atomic-like by increasing the mass of the system, thus making the electronic decay time shorter than the nuclear wavepacket motion associated with the resonant state. In other words, autoionization then occurs faster than the molecular dissociation into neutrals, We acknowledge computer time from the CCC-UAM and Mare Nostrum supercomputer centers and financial support by the European Research Council under the ERC Advanced Grant no. 290853 XCHEM, FP7 Marie Curie ITN CORINF, FP7 Marie Curie IRG ATTOTREND, the Ministerio de Economía y Competitividad projects FIS2010-15127, FIS2013-42002 R and ERA-Chemistry PIM2010EEC-00751, the European COST Action CM1204 XLIC, and EPSRC programme no. EP/I032517/1

1-(2-Heteroarylalkyl)-4-phenylpiperazines containing methyl group in either the alpha- or the beta-position of the side alkyl chain were synthesized as racemic mixtures. They were evaluated for in vitro binding affinity at the D-1 and D-2 dopamine and 5-HT1A serotonin receptors using synaptosomal membranes of the bovine caudate nucleus and hippocampus, respectively, as a source of the corresponding receptors. Tritiated SCH 23390 (D-1 receptor-selective), spiperone (D-2 receptor-selective), and 8-OH-DPAT (5-HT1A receptor-selective) were employed as the radioligands. None of the new compounds expressed significant affinity for the D-1 receptor. Introduction of the methyl group into the beta-position of the parent molecules increased the affinity for the D-2 receptor (10b-13b), and decreased the affinity for the 5-HT1A receptor with the exception of imidazole (11b) which was a rather efficient displacer of 8-OH-DPAT. Most potent of the newly synthesized compounds in [H-3]spiperone assay were compounds (+/-)6-[1-methyl-2-(4-phenylpiperazin-n-1-yl)-ethyl]-1, 4-dihydroquinoxaline-2,3-dione (10b), K-d = 6.0 nM and (+/-)5-[1-methyl-2-(4-phenylpiperazin-1-yl)-ethyl]-1,3-dihydrobenzoirnidazol-2-thione (13b), K-d = 5.3 nM. However, compounds containing methyl group in alpha-position (10a-13a) of the parent molecules expressed a decreased affinity for the D-2 receptor, while the affinity for the 5-HT1A receptor remained in the same range of concentrations as that of closely related achiral parent compounds (14-17) run in the same binding assays as references.

The development of a synthetic approach to the novel pyrrolo[2,1-b][1,3]benzothiazepine and its derivatives and their biological evaluation as potential antipsychotic drugs are described. In binding studies these compounds proved to be potent 5-HT2, D-2, and D-3 receptor ligands. The more potent benzothiazepine (+/-)-3b was resolved into its enantiomers by using HPLC techniques. In vitro testing confirmed that (-)-3b is a more potent D-2 receptor ligand, maintaining high affinity for 5-HT2 receptors. In contrast, the (+)-3b enantiomer presents a 35 times higher affinity for 5-HT2 than for dopamine D-2 receptors with a similar dopamine D-1 receptor affinity to that of (-)-3b. Overall, (+)-3b shows an "atypical" neuroleptic binding profile, while (-)-3b has a more "classical" profile. Furthermore pharmacological and biochemical testing displayed that the novel benzothiazepine (+/-)-3b is able to increase the extracellular levels bf dopamine in the rat striatum and causes a dose-related suppression of apomorphine-induced locomotor activity. At low doses (+/-)-3b does not induce catalepsy, showing atypical antipsychotic properties similar to those of olanzapine. These heterocyclic compouds represent new leads for the development of novel antipsychotic drugs with atypical properties.

The adsorption of H2 on metal clusters is of interest in several fields, including metallurgy, catalysis and hydrogen storage. Hydrogen interacting with small Ni clusters is of special interest, as Ni is widely used as a hydrogenation catalyst. In general, reactions of H2 with extended Ni surfaces are well studied, both experimentally1 and theoretically.2 In practically all cases an H2 molecule dissociates upon adsorption on a Ni surface and the H atoms bind in high coordination sites. The dissociation of H2 on Ni is direct, i.e. it does not proceed via a molecular precursor state.1,3 H2 molecules can only bind molecularly on the step sites of a Ni(510) surface if this surface is fully saturated with H atoms.4 Small Ni clusters do not necessarily exhibit the same behavior as extended surfaces. Consequently, the reaction of gas-phase Ni clusters with H2 has been the subject of many studies.5–8 However, detailed information on H binding sites on Ni clusters is scarce. In agreement with what is observed for extended Ni surfaces, it has recently been confirmed by IR spectroscopy that H2 can be molecularly adsorbed on hydrogen saturated Ni clusters.9 It is not clear whether H2 binds molecularly to nickel clusters only once all sites for dissociative adsorption are blocked, or whether already the very first H2 molecule can bind molecularly.