Postnatal cytomegalovirus infection and pulmonary vascular disease in extremely premature infants: A case series

BACKGROUND

Pulmonary vascular disease (PVD) is a major determinant of both morbidity and mortality in extremely low birth weight infants. It is biologically plausible that postnatal cytomegalovirus (pCMV) infection may lead to PVD in premature infants secondary to pneumonitis or via derangement of pulmonary vascular development directly through endothelial dysfunction. Uncertainty remains, however, regarding thresholds for intervention in premature infants with cardiorespiratory instability and presumed CMV infection likely secondary to the limited understanding of the natural history of the disease.

METHODS/RESULTS

We describe four cases of premature infants with clinical and echocardiography features of PVD, in the setting of postnatally acquired CMV. All patients had atypical PVD trajectories, refractory to vasodilator treatment, which improved after initiation of CMV treatment.

CONCLUSION

We highlight the need to consider postnatally acquired CMV infection in patients with PVD non-responsive to standard pulmonary vasodilator therapies or disease severity which is out of proportion of the usual clinical trajectory. Treatment of extremely premature infants with CMV-associated PVD may have positive impact on cardiorespiratory health, although duration of therapy remains uncertain.

Compassion-focused therapy (CFT) for the reduction of the self-stigma of mental disorders: the COMpassion for Psychiatric disorders, Autism and Self-Stigma (COMPASS) study protocol for a randomized controlled study

BACKGROUND

People with mental disorders face frequent stigmatizing attitudes and behaviors from others. Importantly, they can internalize such negative attitudes and thus self-stigmatize. Self-stigma is involved in diminished coping skills leading to social avoidance and difficulties in adhering to care. Reducing self-stigma and its emotional corollary, shame, is thus crucial to attenuate the negative outcomes associated with mental illness. Compassion-focused therapy (CFT) is a third-wave cognitive behavioral therapy that targets shame reduction and hostile self-to-self relationship and allows for symptom improvement while increasing self-compassion. Although shame is a prominent part of the concept of self-stigma, the efficacy of CFT has never been evaluated in individuals with high levels of self-stigma. The purpose of this study is to evaluate the efficacy and acceptability of a group-based CFT program on self-stigma, compared to a psychoeducation program for self-stigma (Ending Self-Stigma) and to treatment as usual (TAU). We hypothesize that diminished shame and emotional dysregulation and increased self-compassion will mediate the relationship between self-stigma improvements post-therapy in the experimental group.

METHODS

This seven-center trial will involve 336 participants diagnosed with a severe mental illness and/or autism spectrum disorder and reporting high levels of self-stigma. Participants will be randomized into one of three treatment arms: 12 week-treatment of compassion-focused therapy (experimental arm), 12 week-treatment of Psychoeducation (active control arm), and TAU (treatment as usual-passive control arm). The primary outcome is the decrease of self-stigma scores on a self-report scale, i.e., ISMI, at 12 weeks. Secondary endpoints include sustainability of self-stigma scores (ISMI) and self-reported scores regarding target psychological dimensions, e.g., shame and emotional regulation, social functioning, and psychiatric symptoms. Assessments are scheduled at pretreatment, post-treatment (at 12 weeks), and at 6-month follow-up. Acceptability will be evaluated via (i) the Credibility and Expectancy Questionnaire at T0, (ii) the Consumer Satisfaction Questionnaire for Psychotherapeutic Services posttreatment and at 6-month follow-up, (iii) attendance, and (iv) dropout rates.

DISCUSSION

This study will evaluate the potential efficacy and acceptability of a group-based CFT program on the decrease of self-stigma and thereby contribute to the continuing development of evidence-based therapeutic interventions for the internalized stigma of mental and neurodevelopmental disorders.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05698589. Registered on January 26, 2023.

[Anticholinergic scales: Use in psychiatry and update of the anticholinergic impregnation scale]

Anticholinergic properties are well known to prescribers, notably in mental health, as a therapeutic strategy for i.e. extrapyramidal syndrome but also as a source of numerous adverse side effects. Herein, we propose a narrative literature review describing: (i) cholinergic pharmacology and anticholinergic properties; (ii) the importance of anticholinergic therapeutic properties in psychiatry; (iii) the existing anticholinergic drug scales and their usage limitations in Psychiatry and; last (iv) an update to the anticholinergic drug impregnation scale, designed for the French psychiatry practice. The anticholinergic side effects can appear both in the peripheral level (dry mouth, constipation, etc.) and in the central level (especially as cognitive deficits). Many of the so called « anticholinergic » drugs are in fact entirely or mostly antimuscarinic and act essentially as parasympathetic system antagonists. Overall, anticholinergic/antimuscarinic side effects are usually attributed to psychotropic medications: to certain antipsychotics, notably classical neuroleptics such as phenothiazine and also to tricyclic antidepressants. In practice, the impact of anticholinergic toxicity treatments is often highlighted due to their excessively prolonged use in patients on antipsychotics. Interestingly, these antipsychotic treatments are better known for their anticholinergic side effects, especially cognitive ones, with an early onset specially in elder patients and/or in the case of polymedication. In order to evaluate anticholinergic side effects, metrics known as anticholinergic burden scales were created in the last few decades. Nowadays, 13 different scales are documented and accepted by the international academic community, but only three of them are commonly used: the Anticholinergic Drug Scale (ADS), the Anticholinergic Risk Scale (ARS) and the Anticholinergic Burden Scale (ACB). All of them are based on a similar principle, consisting of grading treatments individually, and they are normally scored from 0 - no presence of side effects - to 3 - anticholinergic effects considered to be strong or very strong. Using these scales enables the calculation of the so-called "anticholinergic burden", which corresponds to the cumulative effect of using multiple medications with anticholinergic properties simultaneously. The application of anticholinergic scales to patients with psychiatric disorders has revealed that schizophrenic patients seem to be especially sensitive to anticholinergic cognitive side effects, while elder and depressed patients were more likely to show symptoms of dementia when exposed to higher anticholinergic burden. Unfortunately, these tools appear to have a low parallel reliability, and so they might induce large differences when assessing side effects predictability. In addition, the capacity of these scales to predict central adverse effects is limited due to the fact they poorly or do not differentiate, the ability of treatments to cross the blood-brain barrier. Finally, one last limitation on the validity of these scales is prescription posology is not accounted for side effects considered to be dose dependent. Recently, the MARANTE (Muscarinic Acetylcholine Receptor ANTagonist Exposure) scale has incorporated an anticholinergic burden weighting by posology. Nevertheless, this new model can be criticized, due to the limited number of medications included and due to testing a limited number of potency ranges and dosages for each treatment. Herein, we propose an update to the Anticholinergic Impregnation Scale, developed specifically for the French Psychiatry practice. The scale validation was based on an evaluation of the prescriptions correcting anticholinergic peripheral side effects (constipation, xerostomia and xeropthalmia). This indirect evaluation allowed us to show patients with an anticholinergic impregnation score higher than 5 received significantly more treatments for constipation and xerostomia. This strategy bypasses the bias of a cognitive evaluation in patients with severe mental health disorders. Moreover, the relevance of a tool developed specifically for French psychiatry is justified by the fact that some highly prescribed treatments for mental illness in France (cyamemazine and tropatemine) are strong anticholinergics, and also by the fact they are rarely included in the existing anticholinergic scales. This update of the original scale, published in 2017, includes information whether prescribed drugs cross the blood-brain barrier and thus makes possible a more accurate assessment when evaluating anticholinergic central side effects. Finally, the anticholinergic impregnation scale will soon be integrated into a prescription help software, which is currently being developed to take into consideration dose dependent adverse effects.

Psychotropics and COVID-19: An analysis of safety and prophylaxis

The use of psychotropics during the COVID-19 pandemic has raised two questions, in order of importance: first, what changes should be made to pharmacological treatments prescribed to mental health patients? Secondly, are there any positive side effects of these substances against SARS-CoV-2? Our aim was to analyze usage safety of psychotropics during COVID-19; therefore, herein, we have studied: (i) the risk of symptomatic complications of COVID-19 associated with the use of these drugs, notably central nervous system activity depression, QTc interval enlargement and infectious and thromboembolic complications; (ii) the risk of mistaking the iatrogenic impact of psychotropics with COVID-19 symptoms, causing diagnostic error. Moreover, we provided a summary of the different information available today for these risks, categorized by mental health disorder, for the following: schizophrenia, bipolar disorder, anxiety disorder, ADHD, sleep disorders and suicidal risk. The matter of psychoactive substance use during the pandemic is also analyzed in this paper, and guideline websites and publications for psychotropic treatments in the context of COVID-19 are referenced during the text, so that changes on those guidelines and eventual interaction between psychotropics and COVID-19 treatment medication can be reported and studied. Finally, we also provide a literature review of the latest known antiviral properties of psychotropics against SARS-CoV-2 as complementary information.

Torpedo californica acetylcholinesterase is stabilized by binding of a divalent metal ion to a novel and versatile 4D motif

Stabilization of Torpedo californica acetylcholinesterase by the divalent cations Ca⁺², Mg⁺², and Mn⁺² was investigated. All three substantially protect the enzyme from thermal inactivation. Electron paramagnetic resonance revealed one high‐affinity binding site for Mn⁺² and several much weaker sites. Differential scanning calorimetry showed a single irreversible thermal transition. All three cations raise both the temperature of the transition and the activation energy, with the transition becoming more cooperative. The crystal structures of the Ca⁺² and Mg⁺² complexes with Torpedo acetylcholinesterase were solved. A principal binding site was identified. In both cases, it consists of four aspartates (a 4D motif), within which the divalent ion is embedded, together with several water molecules. It makes direct contact with two of the aspartates, and indirect contact, via waters, with the other two. The 4D motif has been identified in 31 acetylcholinesterase sequences and 28 butyrylcholinesterase sequences. Zebrafish acetylcholinesterase also contains the 4D motif; it, too, is stabilized by divalent metal ions. The ASSAM server retrieved 200 other proteins that display the 4D motif, in many of which it is occupied by a divalent cation. It is a very versatile motif, since, even though tightly conserved in terms of RMSD values, it can contain from one to as many as three divalent metal ions, together with a variable number of waters. This novel motif, which binds primarily divalent metal ions, is shared by a broad repertoire of proteins. An animated Interactive 3D Complement (I3DC) is available in Proteopedia at http://proteopedia.org/w/Journal:Protein_Science:3.

PDB‐ID(s): 7B38, 7B8E and 7B2W;

[Psychopharmacotherapeutic guidelines : a challenge during health crisis]

The construction of pharmacological guidelines is a complex endeavor, and this is all the truer amidst a health crisis such as the current SARS-CoV-2 pandemic. In psychiatric settings, guidelines have to consider the handling of other drugs (i.e., psychotropic medications), that have been suggested as potentially prophylactic for COVID-19. These dialectics are discussed here, and the methodological foundations used for the elaboration of guidelines are put forward.

Elucidating the catalytic degradation of enrofloxacin by copper oxide nanoparticles through the identification of the reactive oxygen species

Copper oxide nanoparticles (CuO-NPs) have been suggested as effective catalysts to degrade many persistent organic contaminants. In parallel, CuO-NPs are considered toxic to soil microorganisms, plants and human cells, possibly because they induce oxidative stress and generation of reactive oxygen species (ROS). However, the mechanism of the catalytic process and the generated ROS are poorly understood. Here we discuss the reaction mechanism of CuO-NPs during the catalytic degradation of enrofloxacin - an antibiotic pharmaceutical used in this study as a representative persistent organic compound. The degradation of an aqueous solution of the enrofloxacin exposed to CuO-NPs and hydrogen peroxide was studied showing fast removal of the enrofloxacin at ambient conditionsns. ROS production was identified by electron spin resonance and a spin trapping technique. The distribution of the free radical species indicated production of a high percentage of superoxide (O₂^-.) radicals as well as hydroxyl radicals; this production is similar to the "radical production" activity of the superoxide dismutase (SOD) enzyme in the presence of hydrogen peroxide. This activity was also tested in the opposite direction, to examine if CuO-NPs show reactivity that potentially mimics the classical SOD enzymatic activity. The CuO-NPs were found to catalyze the dismutation of superoxide to hydrogen peroxide and oxygen in a set of laboratory experiments.

Systematic Quantification of Electron Transfer in a Bare Phospholipid Membrane Using Nitroxide-Labeled Stearic Acids: Distance Dependence, Kinetics, and Activation Parameters

In this report, we present a method to characterize the kinetics of electron transfer across the bilayer of a unilamellar liposome composed of 1,2-dimyristoyl-sn-glycero-3-phosphocholine. The method utilizes synthetic phospholipids containing noninvasive nitroxide spin labels having the >N-O• moiety at well-defined distances from the outer surface of the liposome to serve as reporters for their local environment and, at the same time, permit measurement of the kinetics of electron transfer. We used 5-doxyl and 16-doxyl stearic acids. The paramagnetic >N-O• moiety is photo-oxidized to the corresponding diamagnetic oxoammonium cation by a ruthenium electron acceptor formed in the solution. Electron transfer is monitored by three independent spectroscopic methods: by both steady-state and time-resolved electron paramagnetic resonance and by optical spectroscopy. These techniques allowed us to differentiate between the electron transfer rates of nitroxides located in the outer leaflet of the phospholipid bilayer and of those located in the inner leaflet. Measurement of electron transfer rates as a function of temperature revealed a low-activation barrier (ΔG^‡ ∼ 40 kJ/mol) that supports a tunneling mechanism.

Panic and pandemic: Narrative review of the literature on the links and risks of panic disorder as a consequence of the SARS-CoV-2 pandemic

Although the “panic” word has been abundantly linked to the SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) pandemic in the press, in the scientific literature very few studies have considered whether the current epidemic could predispose to the onset or the aggravation of panic attacks or panic disorder. Indeed, most studies thus far have focused on the risk of increase and aggravation of other psychiatric disorders as a consequence of the SARS-CoV-2 epidemic, such as obsessive-compulsive disorder (OCD), post-traumatic stress disorder (PTSD), and generalized anxiety disorder (GAD). Yet, risk of onset or aggravation of panic disorder, especially the subtype with prominent respiratory symptoms, which is characterized by a fear response conditioning to interoceptive sensations (e.g., respiratory), and hypervigilance to these interoceptive signals, could be expected in the current situation. Indeed, respiratory symptoms, such as coughs and dyspnea, are among the most commonly associated with the SARS-CoV-2 (59–82% and 31–55%, respectively), and respiratory symptoms are associated with a poor illness prognosis. Hence, given that some etiological and maintenance factors associated with panic disorder – i.e., fear conditioning to abnormal breathing patterns attributable or not to the COVID-19 (coronavirus disease 2019), as well as hypervigilance towards breathing abnormalities – are supposedly more prevalent, one could expect an increased risk of panic disorder onset or aggravation following the COVID-19 pandemic in people who were affected by the virus, but also those who were not. In people with the comorbidity (i.e., panic disorder or panic attacks and the COVID-19), it is particularly important to be aware of the risk of hypokalemia in specific at-risk situations or prescriptions. For instance, in the case of salbutamol prescription, which might be overly used in patients with anxiety disorders and COVID-19, or in patients presenting with diarrhea and vomiting. Hypokalemia is associated with an increased risk of torsade de pointe; thus, caution is required when prescribing specific psychotropic drugs, such as the antidepressants citalopram and escitalopram, which are first-line treatments for panic disorder, but also hydroxyzine, aiming at anxiety relief. The results reviewed here highlight the importance of considering and further investigating the impact of the current pandemic on the diagnosis and treatment of panic disorder (alone or comorbid with the COVID-19).

[Panic and pandemic: Review of the literature on the links between panic disorder and the SARS-CoV-2 epidemic]

L’état de panique associé à la pandémie liée au SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) incite à s’interroger sur les troubles anxieux que cette situation pourrait générer ou aggraver. Si la littérature a déjà fourni des projections généralistes en la matière, les données concrètes concernent à ce stage davantage le trouble de stress post-traumatique et le trouble obsessionnel compulsif, tandis que quelques évaluations s’intéressent au cadre nosographie du trouble anxieux généralisé. Le trouble panique ne se voit que peu ou pas cité et l’évocation de la « panique », au sens social, la supplante largement. Bien que d’une légitimité clinique encore débattue, le trouble panique qualifié de « respiratoire » pourrait se voir augmenter en nombre et/ou être intensifié chez les patients qui en présentent déjà. D’éventuelles situations co-morbides entre un tel trouble et la COVID-19 (coronavirus disease 2019) doivent inciter à certaines précautions en matière de prescriptions médicamenteuses, notamment en lien avec les traitements ou situations, sources d’hypokaliémie : (i) le salbutamol, source potentielle de surconsommation, notamment chez les patients anxieux ; (ii) l’infection par le SARS-CoV-2 et plus encore en cas de diarrhées et/ou vomissements. L’hypokaliémie est associée à un risque accru de torsade de pointe, il convient donc également d’être prudent en matière de prescription de psychotropes à risque : comme avec le citalopram et l’escitalopram, des antidépresseurs indiqués dans le trouble panique ou encore l’hydroxyzine, à visée anxiolytique. Ces données sont de nature à resituer l’importance de la prise en considération du trouble panique dans le cadre de la pandémie en cours.

Évolution des phénomènes tachypsychiques en fonction des variations de l’humeur chez deux patients cyclothymiques : données sur 14 semaines issues de l’étude PSYCHE

Introduction

Habituellement décrite dans les états maniaques chez des patients avec troubles de l’humeur, la tachypsychie est définie comme une accélération de la pensée ou « racing thoughts », car les idées se succèdent rapidement contrairement au ralentissement psychomoteur de la dépression. Toutefois, la tachypsychie peut se trouver également associée à des états dépressifs mixtes. Les patients décrivent alors une impression de tête pleine de pensées qui se bousculent, ce qui est décrit par le terme « crowded thoughts » [1]. Peu d’études se sont intéressées à la phénoménologie et à l’évaluation de la tachypsychie. Nous décrivons ici les données obtenues chez deux patients cyclothymiques - une femme et un homme - à l’échelle que nous avons élaborée, le Racing and Crowded Thoughts Questionnaire (RCTQ), dans le cadre de l’étude longitudinale PSYCHE.

Methods

Pendant 14 semaines, le RCTQ, autoquestionnaire composé de 34 items, a été proposé de façon hebdomadaire lors d’une évaluation clinique comprenant les échelles YMRS (manie) et QIDS-C16 (dépression). Des analyses de corrélations intra-sujet entre les résultats à la YMRS et le RCTQ, d’une part, et à la QIDS-C16 et le RCTQ, d’autre part, ont été réalisées.

Résultats

Chez la patiente cyclothymique, une corrélation positive et une tendance à la corrélation négative ont été observées respectivement avec les résultats de la YMRS et de la QIDS-C16. Chez le patient, seuls les résultats à la QIDS-C16 sont corrélés positivement à ceux du RCTQ.

Conclusion

Ces résultats suggèrent que la tachypsychie peut être associée à des états maniaques, mais également à des états dépressifs, notamment ceux accompagnés d’une irritabilité. Une étude de validation du RCTQ est en cours, afin d’évaluer sa structure bifactorielle (« racing » versus « crowded thoughts ») et sa spécificité vis-à-vis des phénomènes voisins, tels que la rumination.

Comment constituer, au sein de la population générale, un échantillon de sujets cyclothymiques ? Expérience à Strasbourg dans le cadre du projet PSYCHE

Contrairement au trouble cyclothymique qui est défini par une labilité affective ayant un impact fonctionnel mais d’intensité et d’une durée insuffisantes pour répondre aux critères d’épisodes thymiques [2], le tempérament cyclothymique se caractérise par les mêmes variations thymiques en l’absence de répercussions [1]. Malgré la prévalence – trouble et tempérament confondus – estimée à 0,4 et 2,5 % de la population générale [3], les études concernant la cyclothymie restent négligées. Dans une revue épidémiologique des troubles bipolaires, parmi une centaine d’études, seules huit concernent la cyclothymie [4]. Peut-on expliquer cette négligence par des difficultés de recrutement de sujets cyclothymiques ? Nous présentons, ici, notre procédure de recrutement de huit sujets avec tempérament ou trouble cyclothymique dans le contexte du projet PSYCHE. Ce projet vise à évaluer un système personnalisé et interactif permettant la surveillance et l’évaluation de variables physiologiques afin de prédire des changements d’humeur. Une annonce a été publiée sur le site Internet et Intranet des hôpitaux universitaires de Strasbourg (HUS). La version brève de la sous-échelle de cyclothymie du TEMPS-A y était proposée. Les coordonnées des sujets dont le score était supérieur ou égal à 9/12 nous étaient envoyées automatiquement. En onze jours, 95 personnes ont eu un score supérieur à 9/12. Des scores de 12, 11, 10 et 9 ont été obtenus respectivement par 19, 15, 24 et 42 % au sein de cette sous-population. Huit sujets ont été recrutés dont sept étaient des collaborateurs des HUS (à rapporter au nombre de collaborateurs en 2011:11962). Notre démarche témoigne de la rapidité et de la facilité d’accessibilité de ce type de population – notamment au sein même des HUS – pour participer à des études cliniques.

Generation of Reactive Oxygen Species by Photosensitizers and their Modes of Action on Proteins

In this review, we first survey the mechanisms underlying the chemical modification of amino acid residues in proteins by singlet oxygen elicited by photosensitizers. Singlet oxygen has the capacity to cause widespread chemical damage to cellular proteins. Its use in photodynamic therapy of tumors thus requires the development of methodologies for specific addressing of the photosensitizer to malignant cells while sparing normal tissue. We describe three targeting paradigms for achieving this objective. The first involves the use of a photosensitizer with a high affinity for its target protein; in this case, the photosensitizer is methylene blue for acetylcholinesterase. The second paradigm involves the use of the hydrophobic photosensitizer hypericin, which has the capacity to interact selectively with partially unfolded forms of proteins, including nascent species in rapidly dividing or virus-infected and cancer cells, acting preferentially at membrane interfaces. In this case, partially unfolded molten globule species of acetylcholinesterase serve as the model system. In the third paradigm, the photodynamic approach takes advantage of a general approach in 'state-of-the-art' chemotherapy, by coupling the photosensitizer emodin to a specific peptide hormone, GnRH, which recognizes malignant cells via specific GnRH receptors on their surface.

Redox-Active Quinone Chelators: Properties, Mechanisms of Action, Cell Delivery, and Cell Toxicity

SIGNIFICANCE

Chemotherapy is currently the principal method for treating many malignancies. Thus, the development of improved antitumor drugs with enhanced efficacy and selectivity remains a high priority. Recent Advances: Anthracycline antibiotics (AAs), for example, doxorubicin, daunomycin, and mitomycin C, belong to an important family of antitumor agents widely used in chemotherapy. These compounds are all quinones. They are, thus, capable of being reduced by appropriate chemicals or reductases. One of their important properties is that under aerobic conditions their reduced forms undergo oxidation, with concomitant generation of reactive oxygen species (ROS), namely, superoxide anion radicals, hydrogen peroxide, and hydroxyl radicals. The presence of metal ions is essential for the generation of ROS by AAs in biological systems.

CRITICAL ISSUES

A fundamental shortcoming of the AAs is their high cardiotoxicity. We have proposed, and experimentally realized, a new type of quinones that is capable of coordinating metal ions. We have demonstrated in vitro that they can be reduced by electron transfer chains and glutathione with concomitant generation of ROS. They can also produce ROS under photo-excitation. The mechanisms of these reactions have been characterized by using nuclear magnetic resonance and electron paramagnetic resonance.

FUTURE DIRECTIONS

To enhance their therapeutic effectiveness, and decrease cardiotoxicity and other side effects, we intend to conjugate the quinone chelators with monoclonal antibodies and peptide hormones that are specifically targeted to receptors on the cancer cell surface. Some such candidates have already been synthesized. An alternative approach for delivery of our compounds involves the use of specific peptide-based nanoparticles. In addition, our novel approach for treating malignancies is also suitable for photodynamic therapy. Antioxid. Redox Signal. 28, 1394-1403.

Cation Binding to Xanthorhodopsin: Electron Paramagnetic Resonance and Magnetic Studies

Xanthorhodopsin (xR) is a member of the retinal protein family and acts as a proton pump in the cell membranes of the extremely halophilic eubacterium Salinibacter ruber. In addition to the retinal chromophore, xR contains a carotenoid, which acts as a light-harvesting antenna as it transfers 40% of the quanta it absorbs to the retinal. Our previous studies have shown that the CD and absorption spectra of xR are dramatically affected due to the protonation of two different residues. It is still unclear whether xR can bind cations. Electron paramagnetic resonance (EPR) spectroscopy used in the present study revealed that xR can bind divalent cations, such as Mn²⁺ and Ca²⁺, to deionized xR (DI-xR). We also demonstrate that xR can bind 1 equiv of Mn²⁺ to a high-affinity binding site followed by binding of ∼40 equiv in cooperative manner and ∼100 equiv of Mn²⁺ that are weakly bound. SQUID magnetic studies suggest that the high cooperative binding of Mn²⁺ cations to xR is due to the formation of Mn²⁺ clusters. Our data demonstrate that Ca²⁺ cations bind to DI-xR with a lower affinity than Mn²⁺, supporting the assumption that binding of Mn²⁺ occurs through cluster formation, because Ca²⁺ cations cannot form clusters in contrast to Mn²⁺.

[IDEM-depression: Characteristics and evaluation of an open group that combines psychoeducation and cognitive-behavior therapy]

INTRODUCTION

Depression is a highly prevalent mental illness that is associated with high rates of morbidity and functional impairment. At the psychiatric unit of the University Hospital of Strasbourg, France, we have developed an open group that combines psychoeducation and cognitive-behavior therapy (CBT), the information, discovery, exchange and mobilization for depression group (IDEM-depression). IDEM-depression is composed of 17 thematic, structured, and independent sessions, which address different aspects of depression (i.e., rumination, pharmacological treatments). Because of its flexible format, patients with varying degrees of depression severity (from remission up to severe depressive symptoms) and whose depression might be bipolar or unipolar, are able to participate in the group. Thus, the group is well suited to a large number of patients with major depression. In the present study we aimed at describing the IDEM-depression group and presenting results regarding patients' overall satisfaction, assessed via two self-report questionnaires (the Client Satisfaction Questionnaire, the CSQ-8, and the IDEM ad hoc questionnaire), as well as its effect on mood following each session assessed via a visual analog scale (VAS) ranging from 0 up to 100.

METHOD

Sixty-five patients participated in 50 sessions of the IDEM-depression group in two hospitals in Alsace. 61% of the patients had bipolar disorder, and 41% of them were inpatients. Sessions took place on a weekly basis, lasted 2hours and were proposed by a CBT-trained clinical psychologist. Patients were asked to fill-out the VAS at the beginning and at the end of each session. Moreover, they were asked to fill-out the CSQ-8 and the IDEM ad hoc questionnaire when they left the group. Other than one session ("yoga and mindfulness"), all the sessions (16 out of 17) were structured on a Powerpoint^© presentation. During the first hour information was given regarding the topic (i.e., rumination), and a shared CBT conceptualization of the topic was formulated by the participants and the psychologist. For most sessions, the first hour was therefore communication and information-based, whereas during the second hour participants were asked to participate in in-session behavioral experiments and/or to evaluate specific aspects of their behavior (thoughts, emotions, activity, mindful behavior) during the last few days. The therapist manual and the slides for each session are available via e-mail to the first author.

RESULTS

Regarding the results, self-reported mood on the VAS was compared between the onset (225 VAS) and the end (225 VAS) of each session. Overall, results suggest that self-reported mood is significantly improved following the participation in sessions (t=-5. 87, P<0.001). Moreover, mean results on the CSQ-8 suggest that patients are highly satisfied with the group (M=24.46, SD=6.42). Among them, 82% reported a moderate-high satisfaction with the group. On the IDEM ad hoc questionnaire, patients reported an overall high satisfaction level regarding (i) the content of sessions, (ii) the duration of sessions, (iii) the frequency of sessions, (iv) how much they felt they could express themselves during sessions. In the qualitative comments of this questionnaire, patients reported that the group helped them to gain an understanding of the mechanisms involved in depression; to feel less isolated and guilty; and to learn about specific psychotherapeutic tools (i.e., mindfulness) and to try to implement them.

CONCLUSION

Our results suggest that an IDEM-depression group is well suited to a wide-array of clinical pictures associated with depression (varying severity, bipolar or unipolar, inpatients and outpatients). This is probably due to its open-group format which is particularly well-adapted to the dynamic symptomatology associated with major depression, and may stimulate decentering in patients who have different levels of severity of symptoms but participate in the same session. Moreover, its impact on mood improvement, and the high satisfaction level reported by patients, seem to be related to its CBT and psychoeducation-based content on the one hand, which has shown its efficacy in depression. On the other hand, IDEM's structured open-group format might have also contributed to the improvement in mood and the overall good satisfaction reported by patients, through the social support provided by the group, improved feeling of self-efficiency, and its effect on stigmatization. Thus, IDEM-depression group is an efficacious, flexible, low-cost, and easy to implement (in different clinical settings) psychotherapeutic option for major depression.

The impact of crystallization conditions on structure-based drug design: A case study on the methylene blue/acetylcholinesterase complex

Structure-based drug design utilizes apoprotein or complex structures retrieved from the PDB. >57% of crystallographic PDB entries were obtained with polyethylene glycols (PEGs) as precipitant and/or as cryoprotectant, but <6% of these report presence of individual ethyleneglycol oligomers. We report a case in which ethyleneglycol oligomers' presence in a crystal structure markedly affected the bound ligand's position. Specifically, we compared the positions of methylene blue and decamethonium in acetylcholinesterase complexes obtained using isomorphous crystals precipitated with PEG200 or ammonium sulfate. The ligands' positions within the active-site gorge in complexes obtained using PEG200 are influenced by presence of ethyleneglycol oligomers in both cases bound to W84 at the gorge's bottom, preventing interaction of the ligand's proximal quaternary group with its indole. Consequently, both ligands are ∼3.0Å further up the gorge than in complexes obtained using crystals precipitated with ammonium sulfate, in which the quaternary groups make direct π-cation interactions with the indole. These findings have implications for structure-based drug design, since data for ligand-protein complexes with polyethylene glycol as precipitant may not reflect the ligand's position in its absence, and could result in selecting incorrect drug discovery leads. Docking methylene blue into the structure obtained with PEG200, but omitting the ethyleneglycols, yields results agreeing poorly with the crystal structure; excellent agreement is obtained if they are included. Many proteins display features in which precipitants might lodge. It will be important to investigate presence of precipitants in published crystal structures, and whether it has resulted in misinterpreting electron density maps, adversely affecting drug design.

Singlet oxygen signatures are detected independent of light or chloroplasts in response to multiple stresses

The production of singlet oxygen is typically associated with inefficient dissipation of photosynthetic energy or can arise from light reactions as a result of accumulation of chlorophyll precursors as observed in fluorescent (flu)-like mutants. Such photodynamic production of singlet oxygen is thought to be involved in stress signaling and programmed cell death. Here we show that transcriptomes of multiple stresses, whether from light or dark treatments, were correlated with the transcriptome of the flu mutant. A core gene set of 118 genes, common to singlet oxygen, biotic and abiotic stresses was defined and confirmed to be activated photodynamically by the photosensitizer Rose Bengal. In addition, induction of the core gene set by abiotic and biotic selected stresses was shown to occur in the dark and in nonphotosynthetic tissue. Furthermore, when subjected to various biotic and abiotic stresses in the dark, the singlet oxygen-specific probe Singlet Oxygen Sensor Green detected rapid production of singlet oxygen in the Arabidopsis (Arabidopsis thaliana) root. Subcellular localization of Singlet Oxygen Sensor Green fluorescence showed its accumulation in mitochondria, peroxisomes, and the nucleus, suggesting several compartments as the possible origins or targets for singlet oxygen. Collectively, the results show that singlet oxygen can be produced by multiple stress pathways and can emanate from compartments other than the chloroplast in a light-independent manner. The results imply that the role of singlet oxygen in plant stress regulation and response is more ubiquitous than previously thought.

Dicobalt-μ-oxo polyoxometalate compound, [(α(2)-P2W17O61Co)2O](14-): a potent species for water oxidation, C-H bond activation, and oxygen transfer

High-valent oxo compounds of transition metals are often implicated as active species in oxygenation of hydrocarbons through carbon-hydrogen bond activation or oxygen transfer and also in water oxidation. Recently, several examples of cobalt-catalyzed water oxidation have been reported, and cobalt(IV) species have been suggested as active intermediates. A reactive species, formally a dicobalt(IV)-μ-oxo polyoxometalate compound [(α2-P2W17O61Co)2O](14-), [(POMCo)2O], has now been isolated and characterized by the oxidation of a monomeric [α2-P2W17O61Co(II)(H2O)](8-), [POMCo(II)H2O], with ozone in water. The crystal structure shows a nearly linear Co-O-Co moiety with a Co-O bond length of ∼1.77 Å. In aqueous solution [(POMCo)2O] was identified by (31)P NMR, Raman, and UV-vis spectroscopy. Reactivity studies showed that [(POMCo)2O]2O] is an active compound for the oxidation of H2O to O2, direct oxygen transfer to water-soluble sulfoxides and phosphines, indirect epoxidation of alkenes via a Mn porphyrin, and the selective oxidation of alcohols by carbon-hydrogen bond activation. The latter appears to occur via a hydrogen atom transfer mechanism. Density functional and CASSCF calculations strongly indicate that the electronic structure of [(POMCo)2O]2O] is best defined as a compound having two cobalt(III) atoms with two oxidized oxygen atoms.

Spinal cord lesions and disability in Hispanics with multiple sclerosis

Longitudinally extensive spinal cord lesions (LESCLs) are believed to occur predominantly with opticospinal multiple sclerosis (OSMS) and are associated with disability. The purpose of this study is to describe the prevalence and patterns of spinal cord lesions in Hispanics with multiple sclerosis (MS) and OSMS and their association with disability. A cross-sectional study of 164 patients with complete MRIs was used. In each case the spinal cord was classified: LESCLs, scattered spinal cord lesions (sSCLs) or no spinal cord lesions (noSCLs). Clinical course was defined as classical MS or OSMS. Risk of disability (Expanded Disability Status Scale ≥4.0) was adjusted for age, disease duration and sex using logistic regression. A total of 125/164 (73 %) MS patients had spinal cord lesions (sSCLs, 57 %; LESCLs, 19 %), but only 11 (7 %) had OSMS. LESCLs were associated with disability (p < 0.0001), longer disease duration (p < 0.0001) and MS (n = 21 vs. n = 10 OSMS; p < 0.0001). LESCLs were also associated with the greatest risk to disability (OR 7.3, 95 % CIs 1.9-26.5; p = 0.003; sSCLs OR 2.5, 95 % CIs 0.9-7.1; p = 0.09) compared with noSCLs. LESCLs are more common than OSMS and are associated with worse disability even in patients with MS. These results suggest that LESCLs are a more important marker of disability in MS than OSMS and may be an early indicator of more aggressive disease in this population.

Structural and functional characterization of the interaction of the photosensitizing probe methylene blue with Torpedo californica acetylcholinesterase

The photosensitizer, methylene blue (MB), generates singlet oxygen that irreversibly inhibits Torpedo californica acetylcholinesterase (TcAChE). In the dark, it inhibits reversibly. Binding is accompanied by a bathochromic absorption shift, used to demonstrate displacement by other acetylcholinesterase inhibitors interacting with the catalytic "anionic" subsite (CAS), the peripheral "anionic" subsite (PAS), or bridging them. MB is a noncompetitive inhibitor of TcAChE, competing with reversible inhibitors directed at both "anionic" subsites, but a single site is involved in inhibition. MB also quenches TcAChE's intrinsic fluorescence. It binds to TcAChE covalently inhibited by a small organophosphate (OP), but not an OP containing a bulky pyrene. Differential scanning calorimetry shows an ~8° increase in the denaturation temperature of the MB/TcAChE complex relative to native TcAChE, and a less than twofold increase in cooperativity of the transition. The crystal structure reveals a single MB stacked against Trp279 in the PAS, oriented down the gorge toward the CAS; it is plausible that irreversible inhibition is associated with photooxidation of this residue and others within the active-site gorge. The kinetic and spectroscopic data showing that inhibitors binding at the CAS can impede binding of MB are reconciled by docking studies showing that the conformation adopted by Phe330, midway down the gorge, in the MB/TcAChE crystal structure, precludes simultaneous binding of a second MB at the CAS. Conversely, binding of ligands at the CAS dislodges MB from its preferred locus at the PAS. The data presented demonstrate that TcAChE is a valuable model for understanding the molecular basis of local photooxidative damage.

Targeted oxidation of Torpedo californica acetylcholinesterase by singlet oxygen

The photosensitizer, methylene blue (MB), is a strong reversible inhibitor of Torpedo californica acetylcholinesterase (AChE) in the dark. Under illumination it causes irreversible inactivation. Loss of fluorescence of the singlet oxygen ((1)O(2)) trap, 9,10-dimethylanthracene, was retarded in the presence of AChE, and the rate of photo-inactivation was increased in the presence of D(2)O, indicating that inactivation was due to (1)O(2) generated by the photosensitizer. CD revealed slightly reduced far-UV ellipticity, and slightly enhanced binding of an amphiphilic probe, indicating limited unfolding of the photo-oxidized AChE. However, both near-UV ellipticity and intrinsic fluorescence were markedly reduced, suggesting photo-oxidative damage to tryptophans, (Trp) supported by appearance of novel emission peaks ascribed to N'-formylkynurenine and/or kynurenine. Like other partially unfolded forms, the photo-oxidized AChE was sensitive to proteolysis. Photosensitized inactivation produced exclusively chemically cross-linked dimers, whereas irradiation of a partially unfolded state generated higher-order oligomers. The active-site gorge of AChE contains Trp in inhibitor-binding sites that might be targets for photo-oxidation. Indeed, reversible inhibitors retard photo-inactivation, and photo-inactivation destroys their binding sites. An excess of AChE protects paraoxonase from photo-inactivation by sequestering the photosensitizer. Affinity photo-oxidation of AChE by MB thus provides a valuable model for studying site-specific photo-inactivation of enzymes in both fundamental and clinical contexts.

[Acute psychotic disorders related to bupropion: review of the literature]

RATIONALE AND OBJECTIVES

Bupropion, or amfebutamone, is an atypical antidepressant also used during tobacco cessation. From a structural standpoint, it resembles amphetamine drugs with psychostimulant effects, and endogenous monoamines. From a pharmacological standpoint, bupropion, and two of its most important active metabolites, inhibit dopamine and norepinephrine reuptake. It has recently been discovered that bupropion may act as a non-competitive cholinergic nicotinic receptor antagonist, and that it may inhibit the activation of reward systems triggered by nicotine. Buproprion's efficacy as a smoking cessation aid has been demonstrated by numerous clinical trials that have compared its effects with those of placebo and other nicotinic substitutes. In 2001, buproprion SR received marketing authorization in France as a smoking cessation aid, under the name ZYBAN®. Tobacco addiction indeed remains a major public health issue. Among patients with psychiatric conditions, chronic tobacco consumption is frequent. The development of non-nicotinic drugs may therefore enhance therapeutic possibilities. However, the psychotropic effects of these molecules should be taken into account. We have recently reported the case of a patient with schizoaffective disorder, who presented two acute bupropion-induced psychotic episodes. We have also undertaken an exhaustive bibliographical research on this subject. The aim of the present study is to present the information available to us, in order to suggest aetiopathogenic hypotheses and therapeutic proposals.

DATA SOURCES

The following databases were consulted on a regular basis, with no date restriction: Medline, Cochrane and Elsevier. The present study identified 22 cases of psychotic conditions associated with buproprion, as well as randomized and pharmacovigilance studies published in English, from December 1985 to November 2008. Since 2002, there have been three published case-reports on patients who underwent a tobacco cessation program.

DATA SYNTHESIS

Psychotic disorders associated with buproprion appear after an average of 10 days of 300 mg/d bupropion intake. In about two third of cases, the patients have no history of psychiatric conditions. In one third of cases, they have a history of thymic disorders. In our review, auditory, visual or cenaesthetic hallucinations frequently occur (85% of the reported cases), and are sometimes characterized by single episodes and/or are rationalized. Some of them occur along with delusional episodes (mystical, paranoid, etc.). The patients are restless, confused, but seldom exhibit dissociative and thymic symptoms.

DISCUSSION AND CONCLUSIONS

From an aetiopathogenic, clinical and evolutive standpoint, buproprion-induced psychotic episodes share many similarities with acute organic or toxic psychosis (notably induced by amphetamines). The hypothesis of a dopaminergic hyper-reactivity should be analyzed. Moreover, most of these patients were taking other medication, and the possibility of a dopaminergic potentialization prior to buproprion intake could be suggested. In such cases, bupropion should be discontinued and complete remission is expected within an average of 10 days. Even though neuroleptic drugs are still frequently used in these cases, benzodiazepines could become a valid alternative, according to the model of amphetamine-induced acute psychosis.

The antidiabetic effect and pharmacokinetic properties of glipizide. Comparison of a single dose with divided dose regime

In 13 patients with maturity-onset diabetes mellitus which did not respond to diet therapy alone, serum concentration of glipizide, blood glucose (B-G) concentration, serum immunoreactive insulin (S-IRI) and plasma glycerol (P-G) were monitored hourly over 12 hours after placebo, an initial dose of glipizide (5 mg p.o.) and long-term treatment with glipizide (range 7.5--20 mg, mean 10.4), which produced fasting B-G of less than 8 mmol/l. During the long-term treatment, glipizide was given in a random, cross-over pattern, either as a single dose in the morning or as a three-part divided dose regime, in the same total daily amount. The duration of the immediate effects of glipizide on B-G, S-IRI and S-IRI/B-G was 9, 4.5 and 6.5 hours, respectively. The mean apparent half-life of glipizide was 4.1 hours, the mean distribution volume 0.13 l/kg and the mean plasma clearance 0.023 l/kg x h. The area under the concentration curve from 7.30 a.m. to 7.30 p.m. was 15% higher after the single dose regime. The serum levels of glipizide at 10 hours were only 30% lower than after the three-part divided dose regime. There were no significant differences between the single and divided dose regimes as regards B-G, S-IRI and S-IRI/B-G, although the mean B-G for the 12-hour period was somewhat lower after the former than after the latter (7.0 against 8.7 mmol/l).

Thiol-disulfide organization in alliin lyase (alliinase) from garlic (Allium sativum)

Alliinase, an enzyme found in garlic, catalyzes the synthesis of the well-known chemically and therapeutically active compound allicin (diallyl thiosulfinate). The enzyme is a homodimeric glycoprotein that belongs to the fold-type I family of pyridoxal-5'-phosphate-dependent enzymes. There are 10 cysteine residues per alliinase monomer, eight of which form four disulfide bridges and two are free thiols. Cys368 and Cys376 form a S--S bridge located near the C-terminal and plays an important role in maintaining both the rigidity of the catalytic domain and the substrate-cofactor relative orientation. We demonstrated here that the chemical modification of allinase with the colored --SH reagent N-(4-dimethylamino-3,5-dinitrophenyl) maleimide yielded chromophore-bearing peptides and showed that the Cys220 and Cys350 thiol groups are accesible in solution. Moreover, electron paramagnetic resonance kinetic measurements using disulfide containing a stable nitroxyl biradical showed that the accessibilities of the two --SH groups in Cys220 and Cys350 differ. Neither enzyme activity nor protein structure (measured by circular dichroism) were affected by the chemical modification of the free thiols, indicating that alliinase activity does not require free --SH groups. This allowed the oriented conjugation of alliinase, via the --SH groups, with low- or high-molecular-weight molecules as we showed here. Modification of the alliinase thiols with biotin and their subsequent binding to immobilized streptavidin enabled the efficient enzymatic production of allicin.

Polyphenol-induced dissociation of various amyloid fibrils results in a methionine-independent formation of ROS

Fibrillization of amyloid polypeptides is accompanied by formation of reactive oxygen species (ROS), which, in turn, is assumed to further promote amyloid-related pathologies. Different polyphenols, all of which are established antioxidants, cause dissociation of amyloid fibrils. This study addresses the latter, poorly understood process. Specifically, we have investigated the dissociation of Abeta(42) fibrils by six different polyphenols, using electron microscopy and spectrofluorometric analysis. Simultanously, we have monitored the production of ROS using electron spin resonance (ESR) and the commercially available peroxide assay kit. Using the same methods we found that curcumin, one of the most potent destabilizing agents of Abeta(42), induced dissociation of fibrils of other amyloid polypeptides [Abeta(40), Abeta(42)Nle35, islet amyloid polypeptide and a fragment of alpha-synuclein]. When the solution contained traces of transition metal, all the dissociation reactions were accompanied by ROS formation, independent of the presence of a methionine residue. Kinetic studies show that the formation of ROS lags behind dissociation, indicating that if casual relationship exists between these two processes, then ROS formation may be considered a consequence and not a cause of dissociation. These findings open new avenues in amyloid research that will be required to gain further understanding of our results and of their implications.