176 research outputs found

    Crisis of Francité: an inquiry into French national identity, language and the state through the ages, The

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    2010 Fall.Includes bibliographical references.Text in French; title and abstract in English and French.This paper deals with the contemporary issues related to French national identity and suggests that they have reached a socio-cultural crisis. It traces the development of French nationalism and the factors that have determined it over the course of the past four centuries. Through an historical lens, the findings suggest that the fortification and increased centralization of the State apparatus coupled with carefully orchestrated state-sanctioned programs pointed at language development have largely been responsible for the construction of the contemporary French nation state entity, its value structure and assertions of uniqueness and singularity. The study follows the historical trajectory of France as it became an icon of the modern era through its leading role in the Enlightenment, its colonial pursuits and domestic nation building efforts. Taking the position that the present can only be understood by a thorough unearthing of the past, this paper holds that current socio-cultural problems in France related to immigration, regional identities and assertions of a threatened national culture are best understood through a holistic archeology of the French national entity

    Microplastics affect sedimentary microbial communities and nitrogen cycling

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    Microplastics are ubiquitous in estuarine, coastal, and deep sea sediments. The impacts of microplastics on sedimentary microbial ecosystems and biogeochemical carbon and nitrogen cycles, however, have not been well reported. To evaluate if microplastics influence the composition and function of sedimentary microbial communities, we conducted a microcosm experiment using salt marsh sediment amended with polyethylene (PE), polyvinyl chloride(PVC), polyurethane foam (PUF) or polylactic acid (PLA) microplastics. We report that the presence of microplastics alters sediment microbial community composition and nitrogen cycling processes. Compared to control sediments without microplastic, PUF- and PLA-amended sediments promote nitrification and denitrification, while PVC amendment inhibits both processes. These results indicate that nitrogen cycling processes in sediments can be significantly affected by different microplastics, which may serve as organic carbon substrates for microbial communities. Considering this evidence and increasing microplastic pollution, the impact of plastics on global ecosystems and biogeochemical cycling merits critical investigation

    Reviewing the Potential of Psychedelics for the Treatment of PTSD

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    There are few medications with demonstrated efficacy for the treatment of posttraumatic stress disorder (PTSD). Treatment guidelines have unequivocally designated psychotherapy as a first line treatment for PTSD. Yet, even after psychotherapy, PTSD often remains a chronic illness, with high rates of psychiatric and medical comorbidity. Meanwhile, the search for and development of drugs with new mechanisms of action has stalled. Therefore, there is an urgent need to explore not just novel compounds but novel approaches for the treatment of PTSD. A promising new approach involves the use of psychedelic drugs. Within the past few years, 2 psychedelics have received breakthrough designations for psychiatric indications from the US Food and Drug Administration, and several psychedelics are currently being investigated for the treatment of PTSD. This review discusses 4 types of compounds: 3,4-methylenedioxymethamphetamine, ketamine, classical psychedelics (e.g., psilocybin and lysergic acid diethylamide), and cannabinoids. We describe the therapeutic rationale, the setting in which they are being administered, and their current state of evidence in the treatment of PTSD. Each compound provides unique qualities for the treatment of PTSD, from their use to rapidly target symptoms to their use as adjuncts to facilitate psychotherapeutic treatments. Several questions are formulated that outline an agenda for future research

    Validation of an LC-MS/MS method for the quantitative analysis of 1P-LSD and its tentative metabolite LSD in fortified urine and serum samples including stability tests for 1P-LSD under different storage conditions

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    A variety of hallucinogens of the lysergamide type has emerged on the drug market in recent years and one such uncontrolled derivative of lysergic acid diethylamide (LSD) is 1 propionyl LSD (1P LSD). Due to the high potency of LSD and some of its derivatives (common doses: 50-200 µg), sensitive methods are required for the analysis of biological samples such as serum and urine. The occurrence of an intoxication case required the development of a fully validated, highly sensitive method for the quantification of 1P LSD and LSD in urine and serum using LC-MS/MS. Given that LSD is unstable in biological samples when exposed to light or elevated temperatures, we also conducted stability tests for 1P LSD in urine and serum under different storage conditions. The validation results revealed that the analysis method was accurate and precise with good linearity over a wide calibration range (0.015-0.4 ng mL-1). The limit of detection (LOD) and the lower limit of quantification (LLOQ) of 1P-LSD and LSD in serum and urine were 0.005 ng mL-1 and 0.015 ng mL-1, respectively. The stability tests showed no major degradation of 1P LSD in urine and serum stored at -20 °C, 5 °C or at room temperature for up to five days, regardless of protection from light. However, LSD was detected in all samples stored at room temperature showing a temperature-dependent hydrolysis of 1P LSD to LSD to some extent (up to 21% in serum). Serum samples were particularly prone to hydrolysis possibly due to enzymatically catalyzed reactions. The addition of sodium fluoride prevented the enzymatic formation of LSD. The method was applied to samples obtained from the intoxication case involving 1P LSD. The analysis uncovered 0.51 ng mL-1 LSD in urine and 3.4 ng mL-1 LSD in serum, whereas 1P LSD remained undetected. So far pharmacokinetic data of 1P LSD is missing, but with respect to the results of our stability tests and the investigated case rapid hydrolysis to LSD in vivo seems more likely than instabilities of 1P¬LSD in urine and serum samples

    Acute Effects of Lysergic Acid Diethylamide on Circulating Steroid Levels in Healthy Subjects

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    Lysergic acid diethylamide (LSD) is a serotonin 5-hydroxytryptamine-2A (5-HT2A ) receptor agonist that is used recreationally worldwide. Interest in LSD research in humans waned after the 1970s, although the use of LSD in psychiatric research and practice has recently gained increasing attention. LSD produces pronounced acute psychedelic effects, although its influence on plasma steroid levels over time has not yet been characterised in humans. The effects of LSD (200 μg) or placebo on plasma steroid levels were investigated in 16 healthy subjects using a randomised, double-blind, placebo-controlled, cross-over study design. Plasma concentration-time profiles were determined for 15 steroids using liquid-chromatography tandem mass-spectrometry. LSD increased plasma concentrations of the glucocorticoids cortisol, cortisone, corticosterone and 11-dehydrocorticosterone compared to placebo. The mean maximum concentration of LSD was reached at 1.7 h. Mean peak psychedelic effects were reached at 2.4 h, with significant alterations in mental state from 0.5 h to > 10 h. Mean maximal concentrations of cortisol and corticosterone were reached at 2.5 h and 1.9 h, and significant elevations were observed 1.5-6 h and 1-3 h after drug administration, respectively. LSD also significantly increased plasma concentrations of the androgen dehydroepiandrosterone but not other androgens, progestogens or mineralocorticoids compared to placebo. A close relationship was found between plasma LSD concentrations and changes in plasma cortisol and corticosterone and the psychotropic response to LSD, and no clockwise hysteresis was observed. In conclusion, LSD produces significant acute effects on circulating steroids, especially glucocorticoids. LSD-induced changes in circulating glucocorticoids were associated with plasma LSD concentrations over time and showed no acute pharmacological tolerance

    The effects of benzofury (5-APB) on the dopamine transporter and 5-HT2-dependent vasoconstriction in the rat

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    5-APB, commonly marketed as ‘benzofury’ is a new psychoactive substance and erstwhile ‘legal high’ which has been implicated in 10 recent drug-related deaths in the UK. This drug was available on the internet and in ‘head shops’ and was one of the most commonly sold legal highs up until its recent UK temporary ban (UK Home Office). Despite its prominence, very little is known about its pharmacology. This study was undertaken to examine the pharmacology of 5-APB in vitro. We hypothesized that 5-APB would activate the dopamine and 5-HT systems which may underlie its putative stimulant and hallucinogenic effects. Autoradiographic studies showed that 5-APB displaced both [125I]RTI-121 and [3H]ketanserin from rat brain tissue suggesting affinity at the dopamine transporter and 5-HT2 receptor sites respectively. Voltammetric studies in rat accumbens brain slices revealed that 5-APB slowed dopamine reuptake, and at high concentrations caused reverse transport of dopamine. 5-APB also caused vasoconstriction of rat aorta, an effect antagonized by the 5-HT2A receptor antagonist ketanserin, and caused contraction of rat stomach fundus, which was reversed by the 5-HT2B receptor antagonist RS-127445. These data show that 5-APB interacts with the dopamine transporter and is an agonist at the 5-HT2A and 5-HT2B receptors in the rat. Thus 5-APB’s pharmacology is consistent with it having both stimulant and hallucinogenic properties. In addition, 5-APB’s activity at the 5-HT2B receptor may cause cardiotoxicity

    Neurovascular and neuroimaging effects of the hallucinogenic serotonin receptor agonist psilocin in the rat brain.

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    The development of pharmacological magnetic resonance imaging (phMRI) has presented the opportunity for investigation of the neurophysiological effects of drugs in vivo. Psilocin, a hallucinogen metabolised from psilocybin, was recently reported to evoke brain region-specific, phMRI signal changes in humans. The present study investigated the effects of psilocin in a rat model using phMRI and then probed the relationship between neuronal and haemodynamic responses using a multimodal measurement preparation. Psilocin (2 mg/kg or 0.03 mg/kg i.v.) or vehicle was administered to rats (N = 6/group) during either phMRI scanning or concurrent imaging of cortical blood flow and recording of local field potentials. Compared to vehicle controls psilocin (2 mg/kg) evoked phMRI signal increases in a number of regions including olfactory and limbic areas and elements of the visual system. PhMRI signal decreases were seen in other regions including somatosensory and motor cortices. Investigation of neurovascular coupling revealed that whilst neuronal responses (local field potentials) to sensory stimuli were decreased in amplitude by psilocin administration, concurrently measured haemodynamic responses (cerebral blood flow) were enhanced. The present findings show that psilocin evoked region-specific changes in phMRI signals in the rat, confirming recent human data. However, the results also suggest that the haemodynamic signal changes underlying phMRI responses reflect changes in both neuronal activity and neurovascular coupling. This highlights the importance of understanding the neurovascular effects of pharmacological manipulations for interpreting haemodynamic neuroimaging data

    LSD Acutely Impairs Fear Recognition and Enhances Emotional Empathy and Sociality

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    Lysergic acid diethylamide (LSD) is used recreationally and has been evaluated as an adjunct to psychotherapy to treat anxiety in patients with life-threatening illness. LSD is well-known to induce perceptual alterations, but unknown is whether LSD alters emotional processing in ways that can support psychotherapy. We investigated the acute effects of LSD on emotional processing using the Face Emotion Recognition Task (FERT) and Multifaceted Empathy Test (MET). The effects of LSD on social behavior were tested using the Social Value Orientation (SVO) test. Two similar placebo-controlled, double-blind, random-order, crossover studies were conducted using 100 μg LSD in 24 subjects and 200 μg LSD in 16 subjects. All of the subjects were healthy and mostly hallucinogen-naive 25- to 65-year-old volunteers (20 men, 20 women). LSD produced feelings of happiness, trust, closeness to others, enhanced explicit and implicit emotional empathy on the MET, and impaired the recognition of sad and fearful faces on the FERT. LSD enhanced the participants' desire to be with other people and increased their prosocial behavior on the SVO test. These effects of LSD on emotion processing and sociality may be useful for LSD-assisted psychotherapy

    Sensory dynamics of visual hallucinations in the normal population.

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    Hallucinations occur in both normal and clinical populations. Due to their unpredictability and complexity, the mechanisms underlying hallucinations remain largely untested. Here we show that visual hallucinations can be induced in the normal population by visual flicker, limited to an annulus that constricts content complexity to simple moving grey blobs, allowing objective mechanistic investigation. Hallucination strength peaked at ~11 Hz flicker and was dependent on cortical processing. Hallucinated motion speed increased with flicker rate, when mapped onto visual cortex it was independent of eccentricity, underwent local sensory adaptation and showed the same bistable and mnemonic dynamics as sensory perception. A neural field model with motion selectivity provides a mechanism for both hallucinations and perception. Our results demonstrate that hallucinations can be studied objectively, and they share multiple mechanisms with sensory perception. We anticipate that this assay will be critical to test theories of human consciousness and clinical models of hallucination
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