Structural Changes Induced by Resveratrol in Monounsaturated and Polyunsaturated Phosphatidylcholine-Enriched Model Membranes.

Resveratrol (Resv) is considered to exert a beneficial impact due to its radical scavenger, anti-microbial and anti-inflammatory properties through several mechanisms that could include its interaction with the cell plasma membrane. To address this issue, we investigated the influence of Resv on membrane lipid order and organization in large unilamellar vesicles composed of different lipids and ratios. The studied lipid membrane models were composed of phosphatidylcholine (PC) species (either palmitoyl-docosahexaenoyl phosphatidylcholine (PDPC) or palmitoyl-oleoyl phosphatidylcholine (POPC)), sphingomyelin (SM) and cholesterol (Chol). This study found that the addition of Resv resulted in complex membrane reorganization depending on the degree of fatty acid unsaturation at the sn-2 position, and the Lipid/Resv and SM/Chol ratios. Resv rigidified POPC-containing membranes and increased liquid-ordered (Lo) domain formation in 40/40/20 POPC/SM/Chol mixtures as this increase was lower at a 33/33/34 ratio. In contrast, Resv interacted with PDPC/SM/Chol mixtures in a bimodal manner by fluidizing/rigidifying the membranes in a dose-dependent way. Lo domain formation upon Resv addition occurred via the following bimodal mode of action: Lo domain size increased at low Resv concentrations; then, Lo domain size decreased at higher ones. To account for the variable effect of Resv, we suggest that it may act as a "spacer" at low doses, with a transition to a more "filler" position in the lipid bulk. We hypothesize that one of the roles of Resv is to tune the lipid order and organization of cell plasma membranes, which is closely linked to important cell functions such as membrane sorting and trafficking.

Impact of Truncated Oxidized Phosphatidylcholines on Phospholipase A2 Activity in Mono- and Polyunsaturated Biomimetic Vesicles.

The interplay between inflammatory and redox processes is a ubiquitous and critical phenomenon in cell biology that involves numerous biological factors. Among them, secretory phospholipases A2 (sPLA2) that catalyze the hydrolysis of the sn-2 ester bond of phospholipids are key players. They can interact or be modulated by the presence of truncated oxidized phosphatidylcholines (OxPCs) produced under oxidative stress from phosphatidylcholine (PC) species. The present study examined this important, but rarely considered, sPLA2 modulation induced by the changes in biophysical properties of PC vesicles comprising various OxPC ratios in mono- or poly-unsaturated PCs. Being the most physiologically active OxPCs, 1-palmitoyl-2-(5'-oxo-valeroyl)-sn-glycero-3-phosphocholine (POVPC) and 1-palmitoyl-2-glutaryl-sn-glycero-3-phosphocholine (PGPC) have been selected for our study. Using fluorescence spectroscopy methods, we compared the effect of OxPCs on the lipid order as well as sPLA2 activity in large unilamellar vesicles (LUVs) made of the heteroacid PC, either monounsaturated [1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)], or polyunsaturated [1-palmitoyl-2-docosahexaenoyl-sn-glycero-3-phosphocholine (PDPC)] at a physiological temperature. The effect of OxPCs on vesicle size was also assessed in both the mono- and polyunsaturated PC matrices. Results: OxPCs decrease the membrane lipid order of POPC and PDPC mixtures with PGPC inducing a much larger decrease in comparison with POVPC, indicative that the difference takes place at the glycerol level. Compared with POPC, PDPC was able to inhibit sPLA2 activity showing a protective effect of PDPC against enzyme hydrolysis. Furthermore, sPLA2 activity on its PC substrates was modulated by the OxPC membrane content. POVPC down-regulated sPLA2 activity, suggesting anti-inflammatory properties of this truncated oxidized lipid. Interestingly, PGPC had a dual and opposite effect, either inhibitory or enhancing on sPLA2 activity, depending on the protocol of lipid mixing. This difference may result from the chemical properties of the shortened sn-2-acyl chain residues (aldehyde group for POVPC, and carboxyl for PGPC), being, respectively, zwitterionic or anionic under hydration at physiological conditions.

Real-world effectiveness of long-acting injectable antipsychotic treatments in a nationwide cohort of 12,373 patients with schizophrenia-spectrum disorders.

This mirror-image study aimed to evaluate the real-life effectiveness of long-acting injectable antipsychotics (LAI) in schizophrenia. Patients with schizophrenia initiating LAIs January 2015-December 2016 were enrolled from the French National Health Data System (SNDS). Standardized mean differences (SMD > 0.1 deemed clinically significant) were calculated for psychiatric healthcare resource utilization measures assessed one year before (during oral AP treatment) and one year after LAI initiation. LAI effectiveness was analyzed overall and by age group, gender and compliance to oral AP, defined as exposure to an AP for at least 80% of the year before LAI initiation. 12,373 patients were included. LAIs were more frequently initiated in men (58.1%), young (18-34 years, 42.0%) and non-compliant (63.7%) patients. LAI initiation was effective in reducing the number and duration of psychiatric hospitalizations and psychiatric emergency department (ED) admissions in non-compliant patients (SMD = -0.19, -0.26 and -0.12, respectively), but not in compliant patients. First-generation LAIs, paliperidone and aripiprazole LAIs reduced psychiatric hospitalizations (SMD = -0.20, -0.24, -0.21, respectively) and ED admissions (SMD = -0.15, -0.13, -0.15, respectively). No differences in effectiveness were found for age or gender. In compliant patients, only aripiprazole LAI reduced the number of psychiatric hospitalizations (SMD = -0.13). Risperidone and paliperidone LAIs increased hospitalization duration (SMD = 0.15 and 0.18, respectively). The prescription of LAIs (except risperidone) should be recommended in all non-compliant patients, even in women and patients aged 35 or older. The lower frequency of administration of LAIs than of oral APs may improve compliance and hence reduce the risk of relapse. Aripiprazole LAI may represent a treatment of choice for compliant patients that should be further investigated.

How can we improve the care of patients with schizophrenia in the real-world? A population-based cohort study of 456,003 patients.

An important step to improve outcomes for patients with schizophrenia is to understand treatment patterns in routine practice. The aim of the current study was to describe the long-term management of patients with schizophrenia treated with antipsychotics (APs) in real-world practice. This population-based study included adults with schizophrenia and who had received ≥3 deliveries of an AP from 2012-2017, identified using a National Health Data System. Primary endpoints were real-life prescription patterns, patient characteristics, healthcare utilization, comorbidities and mortality. Of the 456,003 patients included, 96% received oral APs, 17.5% first-generation long-acting injectable APs (LAIs), and 16.1% second generation LAIs. Persistence rates at 24 months after treatment initiation were 23.9% (oral APs), 11.5% (first-generation LAIs) and 20.8% (second-generation LAIs). Median persistence of oral APs, first-generation LAIs and second-generation LAIs was 5.0, 3.3, and 6.1 months, respectively. Overall, 62.1% of patients were administered anxiolytics, 45.7% antidepressants and 28.5% anticonvulsants, these treatments being more frequently prescribed in women and patients aged ≥50 years. Dyslipidemia was the most frequent metabolic comorbidity (16.2%) but lipid monitoring was insufficient (median of one occasion). Metabolic comorbidities were more frequent in women. Standardized patient mortality remained consistently high between 2013 and 2015 (3.3-3.7 times higher than the general French population) with a loss of life expectancy of 17 years for men and 8 years for women. Cancer (20.2%) and cardiovascular diseases (17.2%) were the main causes of mortality, and suicide was responsible for 25.4% of deaths among 18-34-year-olds. These results highlight future priorities for care of schizophrenia patients. The global persistence of APs used in this population was low, whereas rates of psychiatric hospitalization remain high. More focus on specific populations is needed, such as patients aged >50 years to prevent metabolic disturbances and 18-34-year-olds to reduce suicide rates.

Higher stress response and altered quality of life in schizophrenia patients with low membrane levels of docosahexaenoic acid.

Schizophrenia is a severe, chronic, and heterogeneous mental disorder that affects approximately 1% of the world population. Ongoing research aims at clustering schizophrenia heterogeneity into various "biotypes" to identify subgroups of individuals displaying homogeneous symptoms, etiopathogenesis, prognosis, and treatment response. The present study is in line with this approach and focuses on a biotype partly characterized by a specific membrane lipid composition. We have examined clinical and biological data of patients with stabilized schizophrenia, including the fatty acid content of their erythrocyte membranes, in particular the omega-3 docosahexaenoic acid (DHA). Two groups of patients of similar size were identified: the DHA- group (N = 19) with a lower proportion of membrane DHA as compared to the norm in the general population, and the DHAn group (N = 18) with a normal proportion of DHA. Compared to DHAn, DHA- patients had a higher number of hospitalizations and a lower quality of life in terms of perceived health and physical health. They also exhibited significant higher interleukin-6 and cortisol blood levels. These results emphasize the importance of measuring membrane lipid and immunoinflammatory biomarkers in stabilized patients to identify a specific subgroup and optimize non-pharmacological interventions. It could also guide future research aimed at proposing specific pharmacological treatments.

The impact of lipid polyunsaturation on the physical and mechanical properties of lipid membranes.

The lipid composition of cellular membranes and the balance between the different lipid components can be impacted by aging, certain pathologies, specific diets and other factors. This is the case in a subgroup of individuals with psychiatric disorders, such as schizophrenia, where cell membranes of patients have been shown to be deprived in polyunsaturated fatty acids (PUFAs), not only in brain areas where the target receptors are expressed but also in peripheral tissues. This PUFA deprivation thus represents a biomarker of such disorders that might impact not only the interaction of antipsychotic medications with these membranes but also the activation and signaling of the targeted receptors embedded in the lipid membrane. Therefore, it is crucial to understand how PUFAs levels alterations modulate the different physical properties of membranes. In this paper, several biophysical approaches were combined (Laurdan fluorescence spectroscopy, atomic force microscopy, differential scanning calorimetry, molecular modeling) to characterize membrane properties such as fluidity, elasticity and thickness in PUFA-enriched cell membranes and lipid model systems reflecting the PUFA imbalance observed in some diseases. The impact of both the number of unsaturations and their position along the chain on the above properties was investigated. Briefly, data revealed that PUFA presence in membranes increases membrane fluidity, elasticity and flexibility and decreases its thickness and order parameter. Both the level of unsaturation and their position affect these membrane properties.

Fifty years of experience with loxapine for the rapid non-coercive tranquilization of acute behavioral disturbances in schizophrenia patients, and beyond.

INTRODUCTION: Acute behavioral disturbances in psychosis, including agitation, comprise a heterogeneous group of manifestations varying in intensity and duration they last for. They require rapid, non-coercive treatments ranging from verbal de-escalation to the calming effect of pharmacological agents. The treatment goals are reduction of patient suffering and prevention of disease deterioration. Stabilizing rather than sedating is preferred to ensure improved compliance and a stronger therapeutic alliance. Furthermore, animal pharmacology and clinical studies on agitation reveal the robust calming and anxiolytic properties of loxapine. AREAS COVERED: This review covers the pharmacological and clinical history of loxapine along with research developments. It emphasizes the advantages of its multiple formulations ranging from injectable forms and tablets to orally inhaled forms to attain rapid and fine-tuned tranquilization. EXPERT OPINION: Rapid tranquillization is achieved within 2-6 hours using liquid orally-consumed loxapine, and within an hour or less with its IM or orally inhaled forms. Loxapine has been adopted in the management of a wide range of acute disturbances, such as agitation in psychosis. In the context of personalized medicine, key cellular and molecular elements of the schizophrenia phenotype were recently shown to be improved with loxapine.

Place of the partial dopamine receptor agonist aripiprazole in the management of schizophrenia in adults: a Delphi consensus study.

BACKGROUND: Aripiprazole is a second-generation antipsychotic, efficacious in patients with schizophrenia during acute episodes. Due to its pharmacological profile, aripiprazole may be of interest in patients with specific clinical profiles who have not been studied extensively in randomised clinical trials. OBJECTIVES: To capture experience with aripiprazole in everyday psychiatric practice using the Delphi method in order to inform decision-making on the use of aripiprazole for the treatment of patients with schizophrenia in clinical situations where robust evidence from clinical trials is lacking. METHODS: The scope of the survey was defined as the management of schizophrenia in adults. A systematic literature review was performed to identify the different clinical situations in which aripiprazole has been studied, and to describe the level of clinical evidence. Clinical profiles to include in the Delphi survey were selected if there was a clear interest in terms of medical need but uncertainty over the efficacy of aripiprazole. For each clinical profile retained, five to seven specific statements were generated and included in a questionnaire. The final 41-item questionnaire was proposed to a panel of 406 French psychiatrists with experience in the treatment of schizophrenia. Panellists rated their level of agreement using a Likert scale. A second round of voting on eleven items was organised to clarify points for which a consensus was not obtained in the first round. RESULTS: Five clinical profiles were identified in the literature review (persistent negative symptoms, pregnancy, cognitive dysfunction, addictive comorbidity and clozapine resistance). Sixty-two psychiatrists participated in the first round of the Delphi survey and 33 in the second round. A consensus was obtained for 11 out of 41 items in the first round and for 9/11 items in the second round. According to the panellists' clinical experience, aripiprazole can be used as maintenance treatment for pregnant women, is relevant to preserve cognitive function and can be considered an option in patients with a comorbid addictive disorder or with persistent negative symptoms. CONCLUSION: These findings may help physicians in choosing relevant ways to use aripiprazole and highlight areas where more research is needed to widen the evidence base.

Electroporation, electrochemotherapy and electro-assisted drug delivery in cancer. A state-of-the-art review.

This review focuses on electrochemotherapy that consists in the delivery of anti-cancer drugs using high-voltage electrical pulses. Technical issues, choice of drugs, and protocol of drug delivery are still under investigation and no consensus has been achieved yet. The different aspects of electrochemotherapy are discussed in the present paper. It includes interrogations about the choice of the preferred anti-cancer drug and dose to be delivered on the solid tumors. Another promising area is related to the electro-assisted release of nanoparticles (quantum dots) in xenografted solid tumors. Molecular mechanisms of enhanced drug delivery are discussed in terms of high cholesterol level and large fraction of lipid rafts in cancer cells. Electrochemotherapy is a paradigmatic example of cooperation between physicists, biophysicists, chemists, technicians, manufacturers, biologists, clinicians, and patients to improve a very promising treatment delivery in line with the conception of personalized medicine.

Nature and determinants of social actions during a mass shooting.

Reactions to danger have been depicted as antisocial but research has shown that supportive behaviors (e.g., helping injured others, giving information or reassuring others) prevail in life-threatening circumstances. Why is it so? Previous accounts have put the emphasis on the role of psychosocial factors, such as the maintenance of social norms or the degree of identification between hostages. Other determinants, such as the possibility to escape and distance to danger may also greatly contribute to shaping people's reactions to deadly danger. To examine the role of those specific physical constraints, we interviewed 32 survivors of the attacks at 'Le Bataclan' (on the evening of 13-11-2015 in Paris, France). Consistent with previous findings, supportive behaviors were frequently reported. We also found that impossibility to egress, minimal protection from danger and interpersonal closeness with other crowd members were associated with higher report of supportive behaviors. As we delved into the motives behind reported supportive behaviors, we found that they were mostly described as manifesting cooperative (benefits for both interactants) or altruistic (benefits for other(s) at cost for oneself) tendencies, rather than individualistic (benefits for oneself at cost for other(s)) ones. Our results show that supportive behaviors occur during mass shootings, particularly if people cannot escape, are under minimal protection from the danger, and feel interpersonal closeness with others. Crucially, supportive behaviors underpin a diversity of motives. This last finding calls for a clear-cut distinction between the social strategies people use when exposed to deadly danger, and the psychological motivations underlying them.

Author Correction: Tissue damage from neutrophil-induced oxidative stress in COVID-19.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Factors Associated With a Higher Score of Burnout in a Population of 860 French Psychiatrists.

Burnout rates are estimated to be twice as high among healthcare professionals as in the general working population, and studies indicate rising incidence. The present study aimed to identify the contextual factors associated with self-reported burnout rates among French psychiatrists. A total of 860 French or French-speaking psychiatrists completed an online questionnaire when they registered for a major psychiatric conference. The Copenhagen Burnout Inventory, a validated scale that independently appraises personal, work- and patient-related dimensions, was used to assess the degree of perceived burnout. Respondents were divided into lower risk and higher risk groups. The latter contained the 25% of individuals who scored the highest on each of the three dimensions of the CBI scale. Univariate analysis showed that private practice was associated with lower levels of risk on the personal and work-related dimensions. Working for the public sector and long hours were both associated with a higher score on the work-related dimension. Interestingly, none of the variables we investigated, except from poor atmosphere at work, correlated with the patient-related dimension. Among public-sector psychiatrists, female gender, longer hours, and more consultations per week were associated with a higher score on the work-related dimension. Working four or more night shifts per month was significantly associated with a higher score of burnout risk on all three dimensions. Private- and public-sector practitioners who mainly treated patients with schizophrenia had a higher score of burnout risk. Multivariate analysis showed that a poor atmosphere at work, longer hours, and working four or more night shifts were significantly associated with higher score of burnout risk. A nonreassuring working environment and more stressors while treating patients each had a possibly negative impact. Although this study only examined the factors that distinguish between clinicians with the lowest versus highest CBI burnout risk scores, it opens up important avenues for research and development of programs to reduce burnout risk within the French healthcare system.

Social cognition in post-traumatic stress disorder: A systematic review.

OBJECTIVES: Post-traumatic stress disorder (PTSD) is a common psychiatric condition. Patients with PTSD have marked symptoms that significantly impair their social and emotional abilities, and numerous studies have explored this issue. We hypothesized that impairment of social cognition takes part in functional disability of individuals with PTSD. METHODS: We conducted a systematic review by querying PubMed database for the titles of articles published up to February 2018 with the terms [PTSD] [Post traumatic disorder] AND [Emotion recognition] OR [Facial expression of emotion] OR [Facial expression perception] OR [Empathy] OR [Affective empathy] OR [Mentalizing] OR [Social cognition] OR [Theory of Mind] OR [Mental state attribution] OR [Cognitive empathy] OR [Emotional empathy] OR [Social behaviour deficits]. RESULTS: Our results suggest that affective and cognitive aspect of theory of mind is comprehensively disturbed in patients with PTSD, showing a significant impairment in their ability to predict what others feel, think, or believe. They could also be massively altered in their perception of basic emotional expressions whether it is an expression of threat or happiness. Their affective empathy appears to be systematically disturbed and correlated to verbal and/or physical aggressive behaviour. CONCLUSIONS: Social cognition is disturbed in PTSD and should be regarded as an important symptom. Damages in social cognition seem to take part in the functional disability of people with PTSD. We highlight the interest of a systematic assessment of social cognition in the care of patients with PTSD and suggest which tests could be the most relevant for this evaluation. PRACTITIONER POINTS: •PTSD is no longer regarded as a subtype of anxiety disorder, but as part of a new category in the DSM-5. In clinical practice, symptoms tied to alterations in arousal and reactivity - such as irritability and vigilance - and to the disturbance of cognition and mood, are particularly closely correlated with poorer quality of life. Impaired social cognition clearly impacts the functional disability of people with PTSD. There are potential benefits of individualized cognitive remediation based on empathy and the emotional component of ToM (cognitive remediation, cognitive-behavioural therapy, therapeutic education, etc.) in PTSD people.

An update on the anxiolytic and neuroprotective properties of etifoxine: from brain GABA modulation to a whole-body mode of action.

Treating the signs and symptoms of anxiety is an everyday challenge in clinical practice. When choosing between treatment options, anxiety needs to be understood in the situational, psychiatric, and biological context in which it arises. Etifoxine, a non-benzodiazepine anxiolytic drug belonging to the benzoxazine class, is an effective treatment for anxiety in response to a stressful situation. In the present review, we focused on several aspects of the cerebral and somatic biological mechanisms involved in anxiety and investigated the extent to which etifoxine's mode of action can explain its anxiolytic activity. Its two mechanisms of action are the modulation of GABAergic neurotransmission and neurosteroid synthesis. Recent data suggest that the molecule possesses neuroprotective, neuroplastic, and anti-inflammatory properties. Etifoxine was first shown to be an effective anxiolytic in patients in clinical studies comparing it with clobazam, sulpiride, and placebo. Randomized controlled studies have demonstrated its anxiolytic efficacy in patients with adjustment disorders (ADs) with anxiety, showing it to be superior to buspirone and comparable to lorazepam and phenazepam, with a greater number of markedly improved responders and a better therapeutic index. Etifoxine's noninferiority to alprazolam has also been demonstrated in a comparative trial. Significantly less rebound anxiety was observed after abrupt cessation of etifoxine compared with lorazepam or alprazolam. Consistent with this finding, etifoxine appears to have a very low dependence potential. Unlike lorazepam, it has no effect on psychomotor performance, vigilance, or free recall. Severe adverse events are in general rare. Skin and subcutaneous disorders are the most frequently reported, but these generally resolve after drug cessation. Taken together, its dual mechanisms of action in anxiety and the positive data yielded by clinical trials support the use of etifoxine for treating the anxiety signs and symptoms of individuals with ADs.

[Organic and psychiatric intricacy: The complex psychiatric disorder concept, paraclinical investigations]. / Intrications organo-psychiatriques : le concept de troubles psychiatriques complexes, quels examens complémentaires ?

The purpose of this article is to describe complex psychiatric disorders, to recall "minimal classical" explorations in psychiatry, to describe the concept of "complex psychiatric disorders" and to propose a systematized method of exploration. Some organic diseases are well known for their links with psychiatric disorders (manic syndrome and hyperthyroidism, depressive syndrome and corticotropic insufficiency, anxiety disorder and heart disease, etc.). Many other neurological, autoimmune, metabolic, paraneoplastic or endocrine pathologies can have essentially psycho-behavioral manifestations before being neurological or systemic. A large number of factors (nutritional, toxic, immunological, etc.), often ignored, influence the links between organicity and psychiatric pathologies. It is necessary to optimize the medical management of these patients in whom the psychiatric diagnosis masks a curable organo-psychiatric cause.

[Contemporary behavioural addictions, an overview and the nursing position]. / Addictions comportementales contemporaines, état des lieux et positionnement soignant.

Behavioural addiction is characterised by thoughts focused on a particular activity and its repetition, with a significant amount of time devoted to this activity at the expense of others. The nurse must adapt to these addicts by treating them as individuals without judging them and by trying to understand how they have tried, through this behaviour, to resolve their issues. The challenge is to reposition the body at the heart of the nursing relationship.

Phospholipase A2-Induced Remodeling Processes on Liquid-Ordered/Liquid-Disordered Membranes Containing Docosahexaenoic or Oleic Acid: A Comparison Study.

Vesicle cycling, which is an important biological event, involves the interplay between membrane lipids and proteins, among which the enzyme phospholipase A2 (PLA2) plays a critical role. The capacity of PLA2 to trigger the budding and fission of liquid-ordered (L(o)) domains has been examined in palmitoyl-docosahexaenoylphosphatidylcholine (PDPC) and palmitoyl-oleoylphosphatidylcholine (POPC)/sphingomyelin/cholesterol membranes. They both exhibited a L(o)/liquid-disordered (L(d)) phase separation. We demonstrated that PLA2 was able to trigger budding in PDPC-containing vesicles but not POPC ones. The enzymatic activity, line tension, and elasticity of the membrane surrounding the L(o) domains are critical for budding. The higher line tension of Lo domains in PDPC mixtures was assigned to the greater difference in order parameters of the coexisting phases. The higher amount of lysophosphatidylcholine generated by PLA2 in the PDPC-containing mixtures led to a less-rigid membrane, compared to POPC. The more elastic L(d) membranes in PDPC mixtures exert a lower counteracting force against the L(o) domain bending.

Revisiting loxapine: a systematic review.

Loxapine is an antipsychotic used in psychiatry for over 40 years with a well-established profile. Loxapine is a dibenzoxazepine tricyclic antipsychotic agent, available for oral, intramuscular and inhalatory administration. In the light of the recent approval by the regulatory agencies of inhaled loxapine for use in the acute treatment of mild-to-moderate agitation in adults affected with schizophrenia or bipolar disorder, this article aims to critically review the available literature on loxapine, irrespective of its formulation. This review examines the efficacy and tolerability of the various formulations of loxapine in the treatment of agitation and aggression in patients affected with schizophrenia, bipolar disorder and other psychiatric conditions. A comprehensive and systematic literature search of PubMed/MEDLINE was conducted, and relevant pharmacodynamic and pharmacokinetic data was included. The findings from the literature were critically reviewed and synthesized. The available data suggests that the antipsychotic efficacy of loxapine is similar to the efficacy of other typical or atypical antipsychotics, with an adverse effects profile comparable to that of the typical antipsychotics at high doses for chronic treatment. As an acute treatment in agitation associated with schizophrenia or bipolar disorder, inhaled loxapine was developed as an innovative and rapid option which appears to be efficacious and tolerable.

Anxiety disorders and GABA neurotransmission: a disturbance of modulation.

Lines of evidence coming from many branches of neuroscience indicate that anxiety disorders arise from a dysfunction in the modulation of brain circuits which regulate emotional responses to potentially threatening stimuli. The concept of anxiety disorders as a disturbance of emotional response regulation is a useful one as it allows anxiety to be explained in terms of a more general model of aberrant salience and also because it identifies avenues for developing psychological, behavioral, and pharmacological strategies for the treatment of anxiety disorder. These circuits involve bottom-up activity from the amygdala, indicating the presence of potentially threatening stimuli, and top-down control mechanisms originating in the prefrontal cortex, signaling the emotional salience of stimuli. Understanding the factors that control cortical mechanisms may open the way to identification of more effective cognitive behavioral strategies for managing anxiety disorders. The brain circuits in the amygdala are thought to comprise inhibitory networks of γ-aminobutyric acid-ergic (GABAergic) interneurons and this neurotransmitter thus plays a key role in the modulation of anxiety responses both in the normal and pathological state. The presence of allosteric sites on the GABAA receptor allows the level of inhibition of neurons in the amygdala to be regulated with exquisite precision, and these sites are the molecular targets of the principal classes of anxiolytic drugs. Changes in the levels of endogenous modulators of these allosteric sites as well as changes in the subunit composition of the GABAA receptor may represent mechanisms whereby the level of neuronal inhibition is downregulated in pathological anxiety states. Neurosteroids are synthesized in the brain and act as allosteric modulators of the GABAA receptor. Since their synthesis is itself regulated by stress and by anxiogenic stimuli, targeting the neurosteroid-GABAA receptor axis represents an attractive target for the modulation of anxiety.